Sample records for sailfin mollies poecilia
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This study focuses on the subacute hematological responses of the Yucatan sailfin molly, Poecilia velifera, exposed to cadmium chloride. Previous studies in other teleosts and mammals have suggested that exposure to cadmium chloride results in a leucocytic response. Fish were exp...
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This study focuses on the subacute hematological responses of the Yucatan sailfin molly, Poecilia velifera, exposed to cadmium chloride. Previous studies in other teleosts and mammals have suggested that exposure to cadmium chloride results in a leucocytic response. Fish were exp...
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TIETZE, S. M.; GERALD, G. W.
2016-01-01
Salinity preference and responses to predatory chemical cues were examined both separately and simultaneously in freshwater (FW) and saltwater (SW)-acclimated sailfin mollies Poecilia latipinna, a euryhaline species. It was hypothesized that P. latipinna would prefer FW over SW, move away from chemical cues from a crayfish predator, and favour predator avoidance over osmoregulation when presented with both demands. Both FW and SW-acclimated P. latipinna preferred FW and actively avoided predator cues. When presented with FW plus predator cues v. SW with no cues, P. latipinna were more often found in FW plus predator cues. These results raise questions pertaining to the potential osmoregulatory stress of salinity transitions in euryhaline fishes relative to the potential fitness benefits and whether euryhalinity is utilized for predator avoidance. This study sheds light on the potential benefits and consequences of being salt tolerant or intolerant and complicates the understanding of the selection pressures that have favoured the different osmoregulatory mechanisms among fishes. PMID:27001481
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Tietze, S M; Gerald, G W
2016-05-01
Salinity preference and responses to predatory chemical cues were examined both separately and simultaneously in freshwater (FW) and saltwater (SW)-acclimated sailfin mollies Poecilia latipinna, a euryhaline species. It was hypothesized that P. latipinna would prefer FW over SW, move away from chemical cues from a crayfish predator, and favour predator avoidance over osmoregulation when presented with both demands. Both FW and SW-acclimated P. latipinna preferred FW and actively avoided predator cues. When presented with FW plus predator cues v. SW with no cues, P. latipinna were more often found in FW plus predator cues. These results raise questions pertaining to the potential osmoregulatory stress of salinity transitions in euryhaline fishes relative to the potential fitness benefits and whether euryhalinity is utilized for predator avoidance. This study sheds light on the potential benefits and consequences of being salt tolerant or intolerant and complicates the understanding of the selection pressures that have favoured the different osmoregulatory mechanisms among fishes. © 2016 The Fisheries Society of the British Isles.
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Müller, Klaus; Smielik, Ievgen; Hütwohl, Jan-Marco; Kuhnert, Klaus-Dieter; Witte, Klaudia
2017-01-01
Abstract The use of computer animation in behavioral research is a state-of-the-art method for designing and presenting animated animals to live test animals. The major advantages of computer animations are: (1) the creation of animated animal stimuli with high variability of morphology and even behavior; (2) animated stimuli provide highly standardized, controlled and repeatable testing procedures; and (3) they allow a reduction in the number of live test animals regarding the 3Rs principle. But the use of animated animals should be attended by a thorough validation for each test species to verify that behavior measured with live animals toward virtual animals can also be expected with natural stimuli. Here we present results on the validation of a custom-made simulation for animated 3D sailfin mollies Poecilia latipinna and show that responses of live test females were as strong to an animated fish as to a video or a live male fish. Movement of an animated stimulus was important but female response was stronger toward a swimming 3D fish stimulus than to a “swimming” box. Moreover, male test fish were able to discriminate between animated male and female stimuli; hence, rendering the animated 3D fish a useful tool in mate-choice experiments with sailfin mollies. PMID:29491964
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Gierszewski, Stefanie; Müller, Klaus; Smielik, Ievgen; Hütwohl, Jan-Marco; Kuhnert, Klaus-Dieter; Witte, Klaudia
2017-02-01
The use of computer animation in behavioral research is a state-of-the-art method for designing and presenting animated animals to live test animals. The major advantages of computer animations are: (1) the creation of animated animal stimuli with high variability of morphology and even behavior; (2) animated stimuli provide highly standardized, controlled and repeatable testing procedures; and (3) they allow a reduction in the number of live test animals regarding the 3Rs principle. But the use of animated animals should be attended by a thorough validation for each test species to verify that behavior measured with live animals toward virtual animals can also be expected with natural stimuli. Here we present results on the validation of a custom-made simulation for animated 3D sailfin mollies Poecilia latipinna and show that responses of live test females were as strong to an animated fish as to a video or a live male fish. Movement of an animated stimulus was important but female response was stronger toward a swimming 3D fish stimulus than to a "swimming" box. Moreover, male test fish were able to discriminate between animated male and female stimuli; hence, rendering the animated 3D fish a useful tool in mate-choice experiments with sailfin mollies.
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Smielik, Ievgen; Hütwohl, Jan-Marco; Gierszewski, Stefanie; Witte, Klaudia; Kuhnert, Klaus-Dieter
2017-01-01
Abstract Animal behavior researchers often face problems regarding standardization and reproducibility of their experiments. This has led to the partial substitution of live animals with artificial virtual stimuli. In addition to standardization and reproducibility, virtual stimuli open new options for researchers since they are easily changeable in morphology and appearance, and their behavior can be defined. In this article, a novel toolchain to conduct behavior experiments with fish is presented by a case study in sailfin mollies Poecilia latipinna. As the toolchain holds many different and novel features, it offers new possibilities for studies in behavioral animal research and promotes the standardization of experiments. The presented method includes options to design, animate, and present virtual stimuli to live fish. The designing tool offers an easy and user-friendly way to define size, coloration, and morphology of stimuli and moreover it is able to configure virtual stimuli randomly without any user influence. Furthermore, the toolchain brings a novel method to animate stimuli in a semiautomatic way with the help of a game controller. These created swimming paths can be applied to different stimuli in real time. A presentation tool combines models and swimming paths regarding formerly defined playlists, and presents the stimuli onto 2 screens. Experiments with live sailfin mollies validated the usage of the created virtual 3D fish models in mate-choice experiments. PMID:29491963
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Müller, Klaus; Smielik, Ievgen; Hütwohl, Jan-Marco; Gierszewski, Stefanie; Witte, Klaudia; Kuhnert, Klaus-Dieter
2017-02-01
Animal behavior researchers often face problems regarding standardization and reproducibility of their experiments. This has led to the partial substitution of live animals with artificial virtual stimuli. In addition to standardization and reproducibility, virtual stimuli open new options for researchers since they are easily changeable in morphology and appearance, and their behavior can be defined. In this article, a novel toolchain to conduct behavior experiments with fish is presented by a case study in sailfin mollies Poecilia latipinna . As the toolchain holds many different and novel features, it offers new possibilities for studies in behavioral animal research and promotes the standardization of experiments. The presented method includes options to design, animate, and present virtual stimuli to live fish. The designing tool offers an easy and user-friendly way to define size, coloration, and morphology of stimuli and moreover it is able to configure virtual stimuli randomly without any user influence. Furthermore, the toolchain brings a novel method to animate stimuli in a semiautomatic way with the help of a game controller. These created swimming paths can be applied to different stimuli in real time. A presentation tool combines models and swimming paths regarding formerly defined playlists, and presents the stimuli onto 2 screens. Experiments with live sailfin mollies validated the usage of the created virtual 3D fish models in mate-choice experiments.
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Phenotypic and genomic plasticity of alternative male reproductive tactics in sailfin mollies.
Fraser, Bonnie A; Janowitz, Ilana; Thairu, Margaret; Travis, Joseph; Hughes, Kimberly A
2014-04-22
A major goal of modern evolutionary biology is to understand the causes and consequences of phenotypic plasticity, the ability of a single genotype to produce multiple phenotypes in response to variable environments. While ecological and quantitative genetic studies have evaluated models of the evolution of adaptive plasticity, some long-standing questions about plasticity require more mechanistic approaches. Here, we address two of those questions: does plasticity facilitate adaptive evolution? And do physiological costs place limits on plasticity? We examine these questions by comparing genetically and plastically regulated behavioural variation in sailfin mollies (Poecilia latipinna), which exhibit striking variation in plasticity for male mating behaviour. In this species, some genotypes respond plastically to a change in the social environment by switching between primarily courting and primarily sneaking behaviour. In contrast, other genotypes have fixed mating strategies (either courting or sneaking) and do not display plasticity. We found that genetic and plastic variation in behaviour were accompanied by partially, but not completely overlapping changes in brain gene expression, in partial support of models that predict that plasticity can facilitate adaptive evolution. We also found that behavioural plasticity was accompanied by broader and more robust changes in brain gene expression, suggesting a substantial physiological cost to plasticity. We also observed that sneaking behaviour, but not courting, was associated with upregulation of genes involved in learning and memory, suggesting that sneaking is more cognitively demanding than courtship.
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Public information influences sperm transfer to females in sailfin molly males.
Nöbel, Sabine; Witte, Klaudia
2013-01-01
In animals, including humans, the social environment can serve as a public information network in which individuals can gather public information about the quality of potential mates by observing conspecifics during sexual interactions. The observing individual itself is also a part of this information network. When recognized by the observed conspecifics as an audience, his/her presence could influence the sexual interaction between those individuals, because the observer might be considered as a potential mate or competitor. One of the most challenging questions in sexual selection to date is how the use of public information in the context of mate choice is linked to the fitness of individuals. Here, we could show that public information influences mate-choice behaviour in sailfin molly males, Poecilia latipinna, and influences the amount of sperm males transfer to a female partner. In the presence of an audience male, males spent less time with the previously preferred, larger of two females and significantly more time with the previously non-preferred, smaller female. When males could physically interact with a female and were faced with an audience male, three audience females or no audience, males transferred significantly more sperm to a female partner in the presence of an audience male than with female audience or no audience and spent less time courting his female partner. This is the first study showing that public information use turns into fitness investment, which is the crucial factor to understand the role of public information in the dynamic processes in sexual selection.
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NASA Technical Reports Server (NTRS)
Snelson, F. F., Jr.
1980-01-01
The applicability of monitoring populations of Poccilia latipinna (sailfin molly) and its reproductive efforts as reliable indicators of environmental effects of aerospace activities in the Kennedy Space Center area was investigated. Results show that the sailfin molly experiences drastic fluctuations in population and reproductive success and is not an appropriate factor for monitoring to establish perturbations of the environment due to space transportation system related activities.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Woodhead, A.D.; Setlow, R.B.; Hart, R.W.
1977-01-01
It is suggested that the viviparous teleost, Poecilia formosa, (Amazon molly) may have wide potential use for aquatic radiation studies. The Amazon molly is a naturally occurring gynogenetic species, in which the eggs are activated after mating with the males of closely related species, without the subsequent genetic contribution from the male. The offspring of a single original female constitute a clone, having identical genotypes. Clones of the genetically homogeneous Amazon molly may prove to be equally as valuable to aquatic radiobiologists as the inbred rodent lines have been to mammalian studies. In many other respects the Amazon molly ismore » a satisfactory laboratory animal. It is robust, easy to rear, and has large broods of young when fully grown. Maintenance costs are low. Details are given of the conditions under which colonies reproduce.« less
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Riesch, Rüdiger; Reznick, David N; Plath, Martin; Schlupp, Ingo
2016-03-10
Cavefishes have long been used as model organisms showcasing adaptive diversification, but does adaptation to caves also facilitate the evolution of reproductive isolation from surface ancestors? We raised offspring of wild-caught surface- and cave-dwelling ecotypes of the neotropical fish Poecilia mexicana to sexual maturity in a 12-month common garden experiment. Fish were raised under one of two food regimes (high vs. low), and this was crossed with differences in lighting conditions (permanent darkness vs. 12:12 h light:dark cycle) in a 2 × 2 factorial design, allowing us to elucidate potential patterns of local adaptation in life histories. Our results reveal a pattern of sex-specific local life-history adaptation: Surface molly females had the highest fitness in the treatment best resembling their habitat of origin (high food and a light:dark cycle), and suffered from almost complete reproductive failure in darkness, while cave molly females were not similarly affected in any treatment. Males of both ecotypes, on the other hand, showed only weak evidence for local adaptation. Nonetheless, local life-history adaptation in females likely contributes to ecological diversification in this system and other cave animals, further supporting the role of local adaptation due to strong divergent selection as a major force in ecological speciation.
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Riesch, Rüdiger; Reznick, David N.; Plath, Martin; Schlupp, Ingo
2016-01-01
Cavefishes have long been used as model organisms showcasing adaptive diversification, but does adaptation to caves also facilitate the evolution of reproductive isolation from surface ancestors? We raised offspring of wild-caught surface- and cave-dwelling ecotypes of the neotropical fish Poecilia mexicana to sexual maturity in a 12-month common garden experiment. Fish were raised under one of two food regimes (high vs. low), and this was crossed with differences in lighting conditions (permanent darkness vs. 12:12 h light:dark cycle) in a 2 × 2 factorial design, allowing us to elucidate potential patterns of local adaptation in life histories. Our results reveal a pattern of sex-specific local life-history adaptation: Surface molly females had the highest fitness in the treatment best resembling their habitat of origin (high food and a light:dark cycle), and suffered from almost complete reproductive failure in darkness, while cave molly females were not similarly affected in any treatment. Males of both ecotypes, on the other hand, showed only weak evidence for local adaptation. Nonetheless, local life-history adaptation in females likely contributes to ecological diversification in this system and other cave animals, further supporting the role of local adaptation due to strong divergent selection as a major force in ecological speciation. PMID:26960566
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Martin, Barbara A.; Saiki, Michael K.
2009-01-01
This study was conducted to characterize trophic relationships of small nonnative fishes and to determine if predation by these fishes contributes to the decline of desert pupfish (Cyprinodon macularius), an endangered cyprinodont on the verge of extinction. We sampled 403 hybrid Mozambique tilapias (Oreochromis mossambica by O. urolepis), 107 redbelly tilapias (Tilapia zillii), 32 longjaw mudsuckers (Gillkhthys mirabilis), 182 western mosquitofish (Gambusia affinis), 222 sailfin mollies (Poecilia latipinna), 63 shortfin mollies (Poecilia mexicana), and 235 porthole livebearers (Poecilurpsis gracilis) from a natural creek and four agricultural drains during September 1999- December 2001. Evidence of piscivory was in gastrointestinal contents of 14 hybrid Mozambique tilapias, 3 redbelly tilapias, 10 longjaw mudsuckers, 8 western mosquitofish, 2 sailfin mollies, and 8 porthole livebearers. Although digestion often was too advanced for identification of fishes consumed by nonnative fishes, remains of desert pupfish were in gastrointestinal contents of a longjaw mudsucker. Our findings, along with Field evidence from other studies that inverse relationships exist between abundances of desert pupfish and nonnative species, are consistent with the hypothesis that predation by nonnative species is contributing to decline of desert pupfish. We suspect that competitive interactions with nonnative fishes might also adversely affect abundance of desert pupfish.
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Taylor, R.C.; Trexler, J.C.; Loftus, W.F.
2001-01-01
We documented patterns of age-structured biotic interactions in four mesocosm experiments with an assemblage of three species of co-occurring fishes from the Florida Everglades, the eastern mosquitofish (Gambusia holbrooki), sailfin molly (Poecilia latipinna), and bluefin killifish (Lucania goodei). These species were chosen based on their high abundance and overlapping diets. Juvenile mosquitofish and sailfin mollies, at a range of densities matching field estimates, were maintained in the presence of adult mosquitofish, sailfin mollies, and bluefin killifish to test for effects of competition and predation on juvenile survival and growth. The mesocosms held 1,200 1 of water and all conditions were set to simulate those in Shark River Slough, Everglades National Park (ENP), USA. We placed floating mats of periphyton and bladderwort in each tank in standard volumes that matched field values to provide cover and to introduce invertebrate prey. Of 15 possible intra- and interspecific age-structured interactions, we found 7 to be present at the densities of these fish found in Shark River Slough marshes. Predation by adult mosquitofish on juvenile fish, including conspecifics, was the strongest effect observed. We also observed growth limitation in mosquitofish and sailfin molly juveniles from intra- and interspecific competition. When maintained at high densities, juvenile mosquitofish changed their diets to include more cladocerans and fewer chironomid larvae relative to low densities. We estimated size-specific gape limitation by adult mosquitofish when consuming juvenile mosquitofish and sailfin mollies. At high field densities, intraspecific competition might prolong the time period when juveniles are vulnerable to predation by adult mosquitofish. These results suggest that path analysis, or other techniques used to document food-web interactions, must include age-specific roles of these fishes.
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May, Thomas W.; Walther, Mike W.; Brumbaugh, William G.
2007-01-01
This report presents raw data on selenium concentrations in samples of water, sediment, detritus, and selected food-chain matrices collected from selected agricultural drains in the southern portion of the Salton Sea during October 2006 and January 2007. Total selenium and selenium species were determined in water samples, whereas total selenium was determined in sediment, detritus, algae, plankton, midge larvae (Family Chironomidae), and two fish species (western mosquitofish, Gambusia affinis, and sailfin molly, Poecilia latipinna).
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Makowicz, A M; Plath, M; Schlupp, I
2010-09-01
Sexual conflict in poeciliid fishes is well-documented, particularly male sexual harassment and its effects on females. For instance, male attempts to force copulations influence female feeding, energy allocation, and preference for shoaling partners. However, there has been little research conducted to determine how the social environment shapes the occurrence and intensity of sexual harassment. In this study we ask whether an audience male influences the sexual behaviors of a focal male, the correlated feeding time reduction of female Poecilia latipinna, and if the size of the audience male (larger or smaller than the focal male) influences these behaviors. We presented a video of a male, either smaller or larger than the focal male, or an empty tank (control) to a female interacting with a male or female partner and measured feeding times and sexual behaviors. We found that male sexual behaviors increased in the presence of an audience male, especially if the audience male was larger than the focal male. Females fed more in the presence of a partner female than in the presence of a male, which was independent of the audience (i.e., video treatment). Focal female aggression towards the partner female increased with the size of the audience male. The present study shows that an audience male has multiple interacting influences on both male and female behavior. Copyright 2010 Elsevier B.V. All rights reserved.
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Population Genomics of the Euryhaline Teleost Poecilia latipinna
Hoover, D.; Travis, J.; Oleksiak, M. F.; Crawford, D. L.
2015-01-01
Global climate change and increases in sea levels will affect coastal marine communities. The conservation of these ecologically important areas will be a challenge because of their wide geographic distribution, ecological diversity and species richness. To address this problem, we need to better understand how the genetic variation of the species in these communities is distributed within local populations, among populations and between distant regions. In this study we apply genotyping by sequencing (GBS) and examine 955 SNPs to determine Sailfin molly (Poecilia latipinna) genetic diversity among three geographically close mangrove salt marsh flats in the Florida Keys compared to populations in southern and northern Florida. The questions we are asking are whether there is sufficient genetic variation among isolated estuarine fish within populations and whether there are significant divergences among populations. Additionally, we want to know if GBS approaches agree with previous studies using more traditional molecular approaches. We are able to identify large genetic diversity within each saltmarsh community (π ≈ 36%). Additionally, among the Florida Key populations and the mainland or between southern and northern Florida regions, there are significant differences in allele frequencies seen in population structure and evolutionary relationships among individuals. Surprisingly, even though the cumulative FST value using all 955 SNPs within the three Florida Key populations is small, there are 29 loci with significant FST values, and 11 of these were outliers suggestive of adaptive divergence. These data suggest that among the salt marsh flats surveyed here, there is significant genetic diversity within each population and small but significant differences among populations. Much of the genetic variation within and among populations found here with GBS is very similar to previous studies using allozymes and microsatellites. However, the meaningful difference
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Population Genomics of the Euryhaline Teleost Poecilia latipinna.
Nunez, J C B; Seale, T P; Fraser, M A; Burton, T L; Fortson, T N; Hoover, D; Travis, J; Oleksiak, M F; Crawford, D L
2015-01-01
Global climate change and increases in sea levels will affect coastal marine communities. The conservation of these ecologically important areas will be a challenge because of their wide geographic distribution, ecological diversity and species richness. To address this problem, we need to better understand how the genetic variation of the species in these communities is distributed within local populations, among populations and between distant regions. In this study we apply genotyping by sequencing (GBS) and examine 955 SNPs to determine Sailfin molly (Poecilia latipinna) genetic diversity among three geographically close mangrove salt marsh flats in the Florida Keys compared to populations in southern and northern Florida. The questions we are asking are whether there is sufficient genetic variation among isolated estuarine fish within populations and whether there are significant divergences among populations. Additionally, we want to know if GBS approaches agree with previous studies using more traditional molecular approaches. We are able to identify large genetic diversity within each saltmarsh community (π ≈ 36%). Additionally, among the Florida Key populations and the mainland or between southern and northern Florida regions, there are significant differences in allele frequencies seen in population structure and evolutionary relationships among individuals. Surprisingly, even though the cumulative FST value using all 955 SNPs within the three Florida Key populations is small, there are 29 loci with significant FST values, and 11 of these were outliers suggestive of adaptive divergence. These data suggest that among the salt marsh flats surveyed here, there is significant genetic diversity within each population and small but significant differences among populations. Much of the genetic variation within and among populations found here with GBS is very similar to previous studies using allozymes and microsatellites. However, the meaningful difference
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Tobler, Michael; Schlupp, Ingo
2005-01-01
The maintenance of sexual reproduction in the face of its supposed costs is a major paradox in evolutionary biology. The Red Queen hypothesis, which states that sex is an adaptation to fast-evolving parasites, is currently one of the most recognized explanations for the ubiquity of sex and predicts that asexual lineages should suffer from a higher parasite load if they coexist with closely related sexuals. We tested this prediction using four populations of the sexual fish species Poecilia latipinna and its asexual relative Poecilia formosa. Contrary to expectation, no differences in parasite load could be detected between the two species. PMID:17148156
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Benjamin, M
1989-01-01
The development of hyaline-cell cartilage attached to membrane (dentary, maxilla, nasal, lacrimal and cleithrum) and cartilage (basioccipital) bones has been studied in the viviparous black molly, Poecilia sphenops. Intramembranous ossification commences before the first appearance of hyaline cells. As hyaline-cell cartilage is densely cellular and as that attached to the dentary, maxilla and cleithrum develops from the periosteum of these membrane bones, it must be regarded as secondary cartilage according to current concepts. It is also argued that the hyaline-cell cartilage attached to the perichondral bone of the basioccipital (a cartilage bone), could also be viewed as secondary. The status of the cartilage on the nasal and lacrimal bones is less clear, for it develops, at least in part, from mucochondroid (mucous connective) tissue. This is the first definitive report of secondary cartilage in any lower vertebrate. The tissue is therefore not restricted to birds and mammals as hitherto believed, and a multipotential periosteum must have arisen early in vertebrate evolution. Images Fig. 1 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:2481666
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Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.; Brumbaugh, William G.
2012-01-01
We assessed the suitability of two nonnative poeciliid fishes—western mosquitofish (Gambusia affinis) and sailfin mollies (Poecilia latipinna)—for monitoring selenium exposure in desert pupfish (Cyprinodon macularius). Our investigation was prompted by a need to avoid lethal take of an endangered species (pupfish) when sampling fish for chemical analysis. Total selenium (SeTot) concentrations in both poeciliids were highly correlated with SeTot concentrations in pupfish. However, mean SeTot concentrations varied among fish species, with higher concentrations measured in mosquitofish than in mollies and pupfish from one of three sampled agricultural drains. Moreover, regression equations describing the relationship of selenomethionine to SeTot differed between mosquitofish and pupfish, but not between mollies and pupfish. Because selenium accumulates in animals primarily through dietary exposure, we examined fish trophic relationships by measuring stable isotopes (δ13C and δ15N) and gut contents. According to δ13C measurements, the trophic pathway leading to mosquitofish was more carbon-depleted than trophic pathways leading to mollies and pupfish, suggesting that energy flow to mosquitofish originated from allochthonous sources (terrestrial vegetation, emergent macrophytes, or both), whereas energy flow to mollies and pupfish originated from autochthonous sources (filamentous algae, submerged macrophytes, or both). The δ15N measurements indicated that mosquitofish and mollies occupied similar trophic levels, whereas pupfish occupied a slightly higher trophic level. Analysis of gut contents showed that mosquitofish consumed mostly winged insects (an indication of terrestrial taxa), whereas mollies and pupfish consumed mostly organic detritus. Judging from our results, only mollies (not mosquitofish) are suitable for monitoring selenium exposure in pupfish.
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Habitat restoration as a means of controlling non-native fish in a Mojave desert Oasis
Scoppettone, G.G.; Rissler, P.H.; Gourley, C.; Martinez, C.
2005-01-01
Non-native fish generally cause native fish decline, and once non-natives are established, control or elimination is usually problematic. Because non-native fish colonization has been greatest in anthropogenically altered habitats, restoring habitat similar to predisturbance conditions may offer a viable means of non-native fish control. In this investigation we identified habitats favoring native over non-native fish in a Mojave Desert oasis (Ash Meadows) and used this information to restore one of its major warm water spring systems (Kings Pool Spring). Prior to restoration, native fishes predominated in warm water (25-32??C) stream and spring-pool habitat, whereas non-natives predominated in cool water (???23??C) spring-pool and marsh/slack water habitat. Native Amargosa pupfish (Cyprinodon nevadensis) and Ash Meadows speckled dace (Rhinichthys osculus nevadensis) inhabited significantly faster mean water column velocities (MWCV) and greater total depth (TD) than non-native Sailfin molly (Poecilia latipinna) and Mosquitofish (Gambusia affinis) in warm water stream habitat, and Ash Meadows speckled dace inhabited significantly faster water than non-natives in cool water stream habitat. Modification of the outflow of Kings Pool Spring from marsh to warm water stream, with MWCV, TD, and temperature favoring native fish, changed the fish composition from predominantly non-native Sailfin molly and Mosquitofish to predominantly Ash Meadows pupfish. This result supports the hypothesis that restoring spring systems to a semblance of predisturbance conditions would promote recolonization of native fishes and deter non-native fish invasion and proliferation. ?? 2005 Society for Ecological Restoration International.
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Kin Recognition in a Clonal Fish, Poecilia formosa
Makowicz, Amber M.; Tiedemann, Ralph; Schlupp, Ingo
2016-01-01
Relatedness strongly influences social behaviors in a wide variety of species. For most species, the highest typical degree of relatedness is between full siblings with 50% shared genes. However, this is poorly understood in species with unusually high relatedness between individuals: clonal organisms. Although there has been some investigation into clonal invertebrates and yeast, nothing is known about kin selection in clonal vertebrates. We show that a clonal fish, the Amazon molly (Poecilia formosa), can distinguish between different clonal lineages, associating with genetically identical, sister clones, and use multiple sensory modalities. Also, they scale their aggressive behaviors according to the relatedness to other females: they are more aggressive to non-related clones. Our results demonstrate that even in species with very small genetic differences between individuals, kin recognition can be adaptive. Their discriminatory abilities and regulation of costly behaviors provides a powerful example of natural selection in species with limited genetic diversity. PMID:27483372
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Saiki, Michael K.; Martin, Barbara A.; Anderson, Thomas W.
2011-01-01
In October 2006, months after shallow experimental ponds in the Salton Sea Basin were filled with water from the Alamo River and Salton Sea, fish were observed in several ponds, although inlets had been screened to exclude fish. During October 2007November 2009, nine surveys were conducted using baited minnow traps to document species and relative abundance of fish. Surveys yielded 3,620 fish representing five species. Desert pupfish (Cyprinodon macularius), the only native species encountered, was the most numerous and comprised >93% of the catch. Nonnative species included western mosquitofish (Gambusia affinis, 4.1%), sailfin molly (Poecilia latipinna, 2.8%), and tilapia (a mixture of hybrid Mozambique tilapia Oreochromis mossambicus ?? O. urolepis and redbelly tilapia Tilapia zillii, <0.1%). Dominance by desert pupfish, which persisted over our 2 years of study, was unusual because surveys conducted in nearby agricultural drains yielded relatively few desert pupfish.
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May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
2007-01-01
This report presents the results for two sampling periods during a 4-year monitoring survey to provide a characterization of selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species, and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species-western mosquitofish (Gambusia affinis), and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Total selenium concentrations in water for both sampling periods ranged from 1.43 to 47.1 micrograms per liter, predominately as selenate, which is typical of waters leached out of selenium-contaminated marine shales under alkaline and oxidizing conditions. Total selenium concentrations ranged from 0.88 to 20.2 micrograms per gram in biota, and from 0.15 to 28.9 micrograms per gram in detritus and sediment.
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Kulczykowska, Ewa; Kalamarz-Kubiak, Hanna; Nietrzeba, Marta; Gozdowska, Magdalena
2015-01-01
ABSTRACT Fish may respond to different social situations with changes in both physiology and behaviour. A unique feature of fish is that social interactions between males and females strongly affect the sexual characteristics of individuals. Here we provide the first insight into the endocrine background of two phenomena that occur in mono-sex groups of the black molly (Poecilia sphenops): masculinization in females and same-sex sexual behaviour, manifested by gonopodial displays towards same-sex tank mates and copulation attempts in males. In socially controlled situations, brain neurohormones impact phenotypic sex determination and sexual behaviour. Among these hormones are the nonapeptides arginine vasotocin (AVT) and isotocin (IT), counterparts of the well-known mammalian arginine vasopressin and oxytocin, respectively. To reveal potential hormone interactions, we measured the concentrations of bioactive AVT and IT in the brain, along with those of the sex steroids 17β-estradiol and 11-ketotestosterone in the gonads, of females, masculinized females, males displaying same-sex sexual behaviour and those who did not. These data were supplemented by morphological and histological analyses of the gonads. Correlations between brain nonapeptides and gonadal steroids strongly suggest a cross talk between hormonal systems. In the black molly, the masculinization process was associated with the production of brain AVT and gonadal steroids, whereas same-sex sexual behaviour involves both brain nonapeptides, but neither of the sex steroids. This study extends current knowledge of endocrine control of phenotypic sex and sexual behaviour in fish and for the first time links brain nonapeptides with the occurrence of male-male sexual behaviour in lower vertebrates. PMID:25527645
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May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
2008-01-01
This report presents the results for two sampling periods (October 2007 and January 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (selenite, selenate, organoselenium), and total suspended solids were determined in water samples, and total selenium was determined in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species?western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 0.97 to 64.5 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.95 to 5.99; plankton, 0.15 to 19.3; midges, 1.39 to 15.4; fish, 3.71 to 25.1; detritus, 0.85 to 21.7; sediment, 0.32 to 7.28.
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May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
2009-01-01
This report presents the results for two sampling periods (April 2008 and July 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples and total selenium was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species - western mosquitofish (Gambusia affinis) and sailfin molly (Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.93 to 44.2 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 0.75 to 3.39; plankton, 0.88 to 4.03; midges, 2.52 to 44.3; fish, 3.37 to 18.9; detritus, 1.11 to 13.6; sediment, 0.11 to 8.93.
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May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
2009-01-01
This report presents the results for two sampling periods (October 2008 and January 2009) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were determined in water samples. Total selenium also was determined in water column particulates and in sediment, detritus, and biota that included algae, plankton, midge larvae (family, Chironomidae), and two fish species (western mosquitofish, Gambusia affinis, and sailfin molly, Poecilia latipinna). In addition, sediments were analyzed for percent total organic carbon and particle size. Mean total selenium concentrations in water for both sampling periods ranged from 1.00 to 33.6 micrograms per liter, predominately as selenate, which is typical of waters where selenium is leached out of selenium-containing marine shales and associated soils under alkaline and oxidizing conditions. Total selenium concentrations (micrograms per gram dry weight) ranged as follows: algae, 1.52 to 8.26; plankton, 0.79 to 3.66; midges, 2.68 to 50.6; fish, 3.09 to 30.4; detritus, 1.78 to 58.0; and sediment, 0.42 to 10.0.
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Wanlop, Atcharaphan; Wongsawad, Chalobol; Prattapong, Pongphol; Wongsawad, Pheravut; Chontananarth, Thapana; Chai, Jong-Yil
2017-01-01
The prevalence of Centrocestus formosanus metacercariae was investigated in ornamental fish purchased from a pet shop in Chiang Mai, Thailand, including Carassius auratus (goldfish), Cyprinus carpio (Koi), Poecilia latipinna (Sailfin Molly), Danio rerio (Zebrafish), and Puntigrus tetrazona (Tiger barb). The parasite species was identified by the morphology of worms as well as by a molecular approach using ITS2. The results showed that 50 (33.3%) of 150 fish examined were infected with the metacercariae. The highest prevalence was found in C. auratus (83.3%), and the highest intensity was noted in C. carpio (70.8 metacercariae/fish). The most important morphological character was the presence of 32–34 circumoral spines on the oral sucker. The phylogenetic studies using the rRNA ITS2 region revealed that all the specimens of C. formosanus in this study were grouped together with C. formosanus in GenBank database. This is the first report on ornamental fish, C. carpio, P. latipinna, D. rerio, and P. tetrazona, taking the role of second intermediate hosts of C. formosanus in Thailand. Prevention and control of metacercarial infection in ornamental fish is urgently needed. PMID:28877579
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Wanlop, Atcharaphan; Wongsawad, Chalobol; Prattapong, Pongphol; Wongsawad, Pheravut; Chontananarth, Thapana; Chai, Jong-Yil
2017-08-01
The prevalence of Centrocestus formosanus metacercariae was investigated in ornamental fish purchased from a pet shop in Chiang Mai, Thailand, including Carassius auratus (goldfish), Cyprinus carpio (Koi), Poecilia latipinna (Sailfin Molly), Danio rerio (Zebrafish), and Puntigrus tetrazona (Tiger barb). The parasite species was identified by the morphology of worms as well as by a molecular approach using ITS2. The results showed that 50 (33.3%) of 150 fish examined were infected with the metacercariae. The highest prevalence was found in C. auratus (83.3%), and the highest intensity was noted in C. carpio (70.8 metacercariae/fish). The most important morphological character was the presence of 32-34 circumoral spines on the oral sucker. The phylogenetic studies using the rRNA ITS2 region revealed that all the specimens of C. formosanus in this study were grouped together with C. formosanus in GenBank database. This is the first report on ornamental fish, C. carpio, P. latipinna, D. rerio, and P. tetrazona, taking the role of second intermediate hosts of C. formosanus in Thailand. Prevention and control of metacercarial infection in ornamental fish is urgently needed.
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Mollie Stevens Smart (1916-2012).
Smart, Laura S; Prochaska, James O
2013-09-01
Presents an obituary for Mollie Stevens Smart (1916-2012). Mollie attended the University of Toronto, from which she graduated with honors in psychology at age 20 in 1936. She studied and worked at the Merrill-Palmer Institute in Detroit, earning a master's degree in child development from the University of Michigan in 1941. She earned her doctorate in educational psychology at the University of Delhi in 1969. An author, teacher, and mentor, Mollie won Fulbright research grants to India and New Zealand and lectured in the United States, India, New Zealand, Canada, and China. She wrote 26 books, most co-authored with her husband, Russell (Rus) C. Smart. Beginning in the 1940s, when Freudian theory had a strong grip on the popular view of child development, the books placed the developing child in the context of family and community systems. The Smarts' best-selling college textbook Children: Development and Relationships (1967, 1973, 1977, 1982) was based on the theories of Erik Erikson and Jean Piaget. Mollie was a member of the American Psychological Association throughout her professional career and held memberships also in the Society for Research in Child Development, the National Council on Family Relations, the Groves Conference on Marriage and Family, and the Fulbright Association. After moving to Ridgefield, Washington, in 2003 with her daughter Ellen following Rus's death in 1996, she applied her great knowledge to advise a community-based organization that serves the needs of new babies born into destitute families. Mollie died at home in Ridgefield on October 22, 2012, at age 96. © 2013 APA, all rights reserved.
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Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California.
Saiki, Michael K; Martin, Barbara A; May, Thomas W
2012-09-01
Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98-58.0 μg Se/g; midge larvae, 12.7-50.6 μg Se/g; mosquitofish, 13.2-20.2 μg Se/g; and mollies, 12.8-30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.
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Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California
Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.
2012-01-01
Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98–58.0 μg Se/g; midge larvae, 12.7–50.6 μg Se/g; mosquitofish, 13.2–20.2 μg Se/g; and mollies, 12.8–30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.
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Schulz-Mirbach, Tanja; Heß, Martin; Plath, Martin
2011-01-01
Background Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. Results The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Conclusions Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis—especially with regard to the application of 3D techniques—for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here. PMID:22110746
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Schulz-Mirbach, Tanja; Hess, Martin; Plath, Martin
2011-01-01
Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis--especially with regard to the application of 3D techniques--for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here.
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ERIC Educational Resources Information Center
Pope, Mary L.; And Others
This story about a girl named Molly is a preprimer designed for children in bilingual Inupiat-English programs in the Alaskan villages of Ambler, Kobuk, Kiana, Noorvik, Selawik, and Shungnak. It follows the first preprimer, "Denny." Each page of text is illustrated with a black-and-white drawing. The English equivalent is given at the…
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Lorenz, J.J.; McIvor, C.C.; Powell, G.V.N.; Frederick, P.C.
1997-01-01
We describe a 9 m2 drop net and removable walkways designed to quantify densities of small fishes in wetland habitats with low to moderate vegetation density. The method permits the collection of small, quantitative, discrete samples in ecologically sensitive areas by combining rapid net deployment from fixed sites with the carefully contained use of the fish toxicant rotenone. This method requires very little contact with the substrate, causes minimal alteration to the habitat being sampled, samples small fishes in an unbiased manner, and allows for differential sampling of microhabitats within a wetland. When used in dwarf red mangrove (Rhizophora mangle) habitat in southern Everglades National Park and adjacent areas (September 1990 to March 1993), we achieved high recovery efficiencies (78–90%) for five common species <110 mm in length. We captured 20,193 individuals of 26 species. The most abundant fishes were sheepshead minnowCyprinodon variegatus, goldspotted killifishFloridichthys carpio, rainwater killifishLucania parva, sailfin mollyPoecilia latipinna, and the exotic Mayan cichlidCichlasoma urophthalmus. The 9 m2 drop net and associated removable walkways are versatile and can be used in a variety of wetland types, including both interior and coastal wetlands with either herbaceous or woody vegetation.
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Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.
2010-01-01
This report summarizes comprehensive findings from a 4-year-long field investigation to document baseline environmental conditions in 29 agricultural drains and ponds operated by the Imperial Irrigation District along the southern border of the Salton Sea. Routine water-quality collections and fish community assessments were conducted on as many as 16 sampling dates at roughly quarterly intervals from July 2005 to April 2009. The water-quality measurements included total suspended solids and total (particulate plus dissolved) selenium. With one exception, fish were surveyed with baited minnow traps at quarterly intervals during the same time period. However, in July 2007, fish surveys were not conducted because we lacked permission from the California Department of Fish and Game for incidental take of desert pupfish (Cyprinodon macularius), an endangered species. During April and October 2006-08, water samples also were collected from seven intensively monitored drains (which were selected from the 29 total drains) for measurement of particulate and dissolved selenium, including inorganic and organic fractions. In addition, sediment, aquatic food chain matrices [particulate organic detritus, filamentous algae, net plankton, and midge (chironomid) larvae], and two fish species (western mosquitofish, Gambusia affinis; and sailfin molly, Poecilia latipinna) were sampled from the seven drains for measurement of total selenium concentrations. The mosquitofish and mollies were intended to serve as surrogates for pupfish, which we were not permitted to sacrifice for selenium determinations. Water quality (temperature, dissolved oxygen, pH, specific conductance, and turbidity) values were typical of surface waters in a hot, arid climate. A few drains exhibited brackish, near-anoxic conditions, especially during summer and fall when water temperatures occasionally exceeded 30 degrees Celsius. Total selenium concentrations in water were directly correlated with salinity and
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Shared and Unique Patterns of Embryo Development in Extremophile Poeciliids
Riesch, Rüdiger; Schlupp, Ingo; Langerhans, R. Brian; Plath, Martin
2011-01-01
Background Closely related lineages of livebearing fishes have independently adapted to two extreme environmental factors: toxic hydrogen sulphide (H2S) and perpetual darkness. Previous work has demonstrated in adult specimens that fish from these extreme habitats convergently evolved drastically increased head and offspring size, while cave fish are further characterized by reduced pigmentation and eye size. Here, we traced the development of these (and other) divergent traits in embryos of Poecilia mexicana from benign surface habitats (“surface mollies”) and a sulphidic cave (“cave mollies”), as well as in embryos of the sister taxon, Poecilia sulphuraria from a sulphidic surface spring (“sulphur mollies”). We asked at which points during development changes in the timing of the involved processes (i.e., heterochrony) would be detectible. Methods and Results Data were extracted from digital photographs taken of representative embryos for each stage of development and each type of molly. Embryo mass decreased in convergent fashion, but we found patterns of embryonic fat content and ovum/embryo diameter to be divergent among all three types of mollies. The intensity of yellow colouration of the yolk (a proxy for carotenoid content) was significantly lower in cave mollies throughout development. Moreover, while relative head size decreased through development in surface mollies, it increased in both types of extremophile mollies, and eye growth was arrested in mid-stage embryos of cave mollies but not in surface or sulphur mollies. Conclusion Our results clearly demonstrate that even among sister taxa convergence in phenotypic traits is not always achieved by the same processes during embryo development. Furthermore, teleost development is crucially dependent on sufficient carotenoid stores in the yolk, and so we discuss how the apparent ability of cave mollies to overcome this carotenoid-dependency may represent another potential mechanism explaining
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Palamar, Joseph J
2017-01-01
Molly has been the street name for powder or crystalline ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) in the United States since the early 2000s; however, few studies have examined Molly use or included Molly in the definition of ecstasy/MDMA. Prevalence of self-reported ecstasy use is being underreported on surveys due to the lack of inclusion of "Molly," although Molly is often so adulterated with novel psychoactive substances such as synthetic cathinones ("bath salts") that the name "Molly" may no longer adequately represent ecstasy/MDMA. The author recommends that Molly use and Molly purity be further studied to more adequately inform prevention and harm reduction.
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Bierbach, David; Riesch, Rüdiger; Schießl, Angela; Wigh, Adriana; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Klaus, Sebastian; Zimmer, Claudia; Plath, Martin
2014-01-01
The Cueva del Azufre in Tabasco, Mexico, is a nutrient-rich cave and its inhabitants need to cope with high levels of dissolved hydrogen sulfide and extreme hypoxia. One of the successful colonizers of this cave is the poeciliid fish Poecilia mexicana, which has received considerable attention as a model organism to examine evolutionary adaptations to extreme environmental conditions. Nonetheless, basic ecological data on the endemic cave molly population are still missing; here we aim to provide data on population densities, size class compositions and use of different microhabitats. We found high overall densities in the cave and highest densities at the middle part of the cave with more than 200 individuals per square meter. These sites have lower H2S concentrations compared to the inner parts where most large sulfide sources are located, but they are annually exposed to a religious harvesting ceremony of local Zoque people called La Pesca. We found a marked shift in size/age compositions towards an overabundance of smaller, juvenile fish at those sites. We discuss these findings in relation to several environmental gradients within the cave (i.e., differences in toxicity and lighting conditions), but we also tentatively argue that the annual fish harvest during a religious ceremony (La Pesca) locally diminishes competition (and possibly, cannibalism by large adults), which is followed by a phase of overcompensation of fish densities. PMID:25083351
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Jourdan, Jonas; Bierbach, David; Riesch, Rüdiger; Schießl, Angela; Wigh, Adriana; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Klaus, Sebastian; Zimmer, Claudia; Plath, Martin
2014-01-01
The Cueva del Azufre in Tabasco, Mexico, is a nutrient-rich cave and its inhabitants need to cope with high levels of dissolved hydrogen sulfide and extreme hypoxia. One of the successful colonizers of this cave is the poeciliid fish Poecilia mexicana, which has received considerable attention as a model organism to examine evolutionary adaptations to extreme environmental conditions. Nonetheless, basic ecological data on the endemic cave molly population are still missing; here we aim to provide data on population densities, size class compositions and use of different microhabitats. We found high overall densities in the cave and highest densities at the middle part of the cave with more than 200 individuals per square meter. These sites have lower H2S concentrations compared to the inner parts where most large sulfide sources are located, but they are annually exposed to a religious harvesting ceremony of local Zoque people called La Pesca. We found a marked shift in size/age compositions towards an overabundance of smaller, juvenile fish at those sites. We discuss these findings in relation to several environmental gradients within the cave (i.e., differences in toxicity and lighting conditions), but we also tentatively argue that the annual fish harvest during a religious ceremony (La Pesca) locally diminishes competition (and possibly, cannibalism by large adults), which is followed by a phase of overcompensation of fish densities.
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Zimmer, Claudia; Bierbach, David; Arias-Rodriguez, Lenin; Plath, Martin
2018-01-01
Divergent selection between ecologically dissimilar habitats promotes local adaptation, which can lead to reproductive isolation (RI). Populations in the Poecilia mexicana species complex have independently adapted to toxic hydrogen sulfide and show varying degrees of RI. Here, we examined the variation in the mate choice component of prezygotic RI. Mate choice tests across drainages (with stimulus males from another drainage) suggest that specific features of the males coupled with a general female preference for yellow color patterns explain the observed variation. Analyses of male body coloration identified the intensity of yellow fin coloration as a strong candidate to explain this pattern, and common-garden rearing suggested heritable population differences. Male sexual ornamentation apparently evolved differently across sulfide-adapted populations, for example because of differences in natural counterselection via predation. The ubiquitous preference for yellow color ornaments in poeciliid females likely undermines the emergence of strong RI, as female discrimination in favor of own males becomes weaker when yellow fin coloration in the respective sulfide ecotype increases. Our study illustrates the complexity of the (partly non-parallel) pathways to divergence among replicated ecological gradients. We suggest that future work should identify the genomic loci involved in the pattern reported here, making use of the increasing genomic and transcriptomic datasets available for our study system. PMID:29724050
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Gregorini, P; Beukes, P C; Hanigan, M D; Waghorn, G; Muetzel, S; McNamara, J P
2013-08-01
Molly is a deterministic, mechanistic, dynamic model representing the digestion, metabolism, and production of a dairy cow. This study compared the predictions of enteric methane production from the original version of Molly (MollyOrigin) and 2 new versions of Molly. Updated versions included new ruminal fiber digestive parameters and animal hormonal parameters (Molly84) and a revised version of digestive and ruminal parameters (Molly85), using 3 different ruminal volatile fatty acid (VFA) stoichiometry constructs to describe the VFA pattern and methane (CH4) production (g of CH4/d). The VFA stoichiometry constructs were the original forage and mixed-diet VFA constructs and a new VFA stoichiometry based on a more recent and larger set of data that includes lactate and valerate production, amylolytic and cellulolytic bacteria, as well as protozoal pools. The models' outputs were challenged using data from 16 dairy cattle 26 mo old [standard error of the mean (SEM)=1.7], 82 (SEM=8.7) d in milk, producing 17 (SEM=0.2) kg of milk/d, and fed fresh-cut ryegrass [dry matter intake=12.3 (SEM=0.3) kg of DM/d] in respiration chambers. Mean observed CH4 production was 266±5.6 SEM (g/d). Mean predicted values for CH4 production were 287 and 258 g/d for MollyOrigin without and with the new VFA construct. Model Molly84 predicted 295 and 288 g of CH4/d with and without the new VFA settings. Model Molly85 predicted the same CH4 production (276 g/d) with or without the new VFA construct. The incorporation of the new VFA construct did not consistently reduce the low prediction error across the versions of Molly evaluated in the present study. The improvements in the Molly versions from MollyOrigin to Molly84 to Molly85 resulted in a decrease in mean square prediction error from 8.6 to 8.3 to 4.3% using the forage diet setting. The majority of the mean square prediction error was apportioned to random bias (e.g., 43, 65, and 70% in MollyOrigin, Molly84, and Molly85, respectively, on
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2014-03-01
originates at a large levee, which was built to create a water retention (to control excess water) and water bird management area. The levee and canal...each sample was dried in stainless steel trays in a 60 °C convection oven . Two methods of quantitative analysis were performed to determine the...ERDC/TN ANSRP-14-1 March 2014 Approved for public release; distribution is unlimited. Burrowing by Sailfin Catfish (Pterygoplichthys sp.): A
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Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.
2008-01-01
This report summarizes findings from the third year of a 4-year-long field investigation to document selected baseline environmental conditions in 29 agricultural drains and ponds operated by the Imperial Irrigation District along the southern border of the Salton Sea. Routine water quality and fish species were measured at roughly quarterly intervals from April 2007 to January 2008. The water quality measurements included total suspended solids and total (particulate plus dissolved) selenium. In addition, during April and October 2007, water samples were collected from seven intensively monitored drains for measurement of particulate and dissolved selenium, including inorganic and organic fractions. In addition, sediment, aquatic food chain matrices (particulate organic detritus, filamentous algae, net plankton, and midge [chironomid] larvae), and two fish species (western mosquitofish, Gambusia affinis; and sailfin molly, Poecilia latipinna) were sampled from the seven drains for measurement of total selenium concentrations. The mosquitofish and mollies were intended to serve as surrogates for desert pupfish (Cyprinodon macularius), an endangered species that we were not permitted to take for selenium determinations. Water quality values were typical of surface waters in a hot desert climate. A few drains exhibited brackish, near anoxic conditions especially during the summer and fall when water temperatures occasionally exceeded 30 degrees C. In general, total selenium concentrations in water varied directly with conductivity and inversely with pH. Although desert pupfish were found in several drains, sometimes in relatively high numbers, the fish faunas of most drains and ponds were dominated by nonnative species, especially red shiner (Cyprinella lutrensis), mosquitofish, and mollies. Dissolved selenium in water samples from the seven intensively monitored drains ranged from 0.700 to 24.1 ug/L, with selenate as the major constituent in all samples. Selenium
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Palamar, Joseph J.
2017-01-01
Molly has been the street name for powder or crystalline ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) in the United States since at least 2008; however, few studies have examined Molly use or included Molly in the definition of ecstasy/MDMA. Prevalence of self-reported ecstasy use is being underreported on surveys due to the lack of inclusion of “Molly”, although Molly is often so adulterated with novel psychoactive substances such as synthetic cathinones (“bath salts”) that the name “Molly” may no longer adequately represent ecstasy/MDMA. The author recommends that Molly use and Molly purity be further studied to more adequately inform prevention and harm reduction. PMID:27925866
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Kavitha, P; Subramanian, P
2011-12-01
The influence of Tribulus terrestris on the activities of testicular enzyme in Poecilia latipinna was assessed in lieu of reproductive manipulation. Different concentrations of (100, 150, 200, 250, and 300 mg) Tribulus terrestris extract and of a control were tested for testicular activity of enzymes in Poecilia latipinna for 2 months. The testis and liver were homogenized separately in 0.1 mol/l potassium phosphate buffer (0.1 mol/l, pH 7.2). The crude homogenate was centrifuged, and supernatant obtained was used as an enzyme extract for determination of activities. The activities of testicular functional enzyme ALP, ACP, SDH, LDH, and G6PDH levels were changed to different extent in treated groups compared with that of the control. The total body weight and testis weight were increased with the Tribulus terrestris-treated fish (Poecilia latipinna). These results suggest that Tribulus terrestris induced the testicular enzyme activity that may aid in the male reproductive functions. It is discernible from the present study that Tribulus terrestris has the inducing effect on reproductive system of Poecilia latipinna.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Majtenyi, Nicholas; Juma, Hanif; Klein, Ran
Dynamic contrast-enhanced (DCE)-MRI is a technique for obtaining tissue hemodynamic information (e.g. tumours). Despite widespread clinical application of DCE-MRI, the technique suffers from a lack of standardization and accuracy, especially with respect to the concentration-versus-time of gadolinium (Gd) in feeding arteries (the input function, IF). MR phase has a linear quantitative relationship with Gd concentration ([Gd]), making it ideal for measuring the first-pass of the IF, but is not considered accurate in the steady-state washout. Modified Look-Locker Inversion Recovery (MOLLI) is a fast and accurate method to measure T1 and has been validated to quantify typical [Gd] ranges experienced inmore » the washout of the IF. Two different methods to measure the IF for DCE-MRI were compared: 1) conventional phase-versus-time (“Phase-only”) and 2) phase-versus-time combined with pre- and post-DCE MOLLI T1 measurements (“Phase+MOLLI”). The IF obtained from Phase+MOLLI was calculated from MOLLI T1 values and known relaxivity, then added to the Phase-only acquisition with the washout IF subtracted. A significant difference was observed between IF values for [Gd] between the Phase-only and Phase+MOLLI acquisitions (P = 0.03). To ensure the IFs from MOLLI T1s were accurate, it was compared to [Gd] obtained from “gold-standard” inversion recovery (IR). MOLLI showed excellent agreement with IR when imaged in static phantoms (r{sup 2} = 0.997, P = 0.001). The Phase+MOLLI IF was more accurate than the Phase-only IF in measuring the washout. The Phase+MOLLI acquisition may therefore provide a DCE-MRI reference standard that could lead to better clinical diagnoses.« less
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EXOCRINE PANCREATIC CARCINOGENESIS IN THE GUPPY POECILIA RETICULATA
Exocrine pancreatic neoplasms developed in the guppy Poecilia reticulata following exposure to the direct acting carcinogen, methylazoxymethanol acetate (MAM-Ac). Fish 6- to 10-days old were exposed to nominal, nontoxic concentrations of 4 and 10 mg MAM-Ac 1-1 for 2 h and then tr...
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Zhang, J M; Zhang, F
2015-06-01
Elaeagnus mollis Diels is a group of shrubs and dwarf trees endemic to China and are endangered plants. However, the reason why these plants are endangered remains controversial. The current study aimed to explore the endangered status of E. mollis from a genetic perspective and to propose conservation strategies for this species. Using 16 polymorphic allozyme loci, the population genetic structure was investigated for three populations representing the taxa and variants. The variants exhibited relatively high levels of genetic variation compared to other woody shrubs with similar geographic distributions. The overall genetic diversity (HE = 0.352) was elevated compared to long-lived woody angiosperms. The average number of alleles per locus (A), percentage polymorphic loci (P), and observed heterozygosity (HO) were 2.0, 85.2, and 0.371, respectively. Furthermore, gene flow estimates within the population groups were also elevated. The life history and habitats of E. mollis play major roles in the levels of genetic diversity. The results of this study may help to device strategies for preserving the genetic diversity of E. mollis and for promoting planting.
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Jin, Zhe-Xiong; Wang, Yue; Zhou, Qun; Chen, Jian-Bo; Ma, Fang; Sun, Su-Qin
2014-09-01
In this study, major chemical components of Flos rhododendri mollis and Flos chrysanthemi indici were characterized using Fourier transform infrared spectroscopy (FTIR). For Flos rhododendri mollis, the bands at 1,648 and 1,543 cm(-1) were attributed to amide I and amide II , respectively, indicating that it contained proteins probably resulting in immunization. In case of Flos chrysanthemi indici, stretching vibration of C==O function group was responsible for the bands at 1,734 and 1,515 cm(-1), as a result of essential oils, lipids, etc. Since FTIR spectra of Flos rhododendri mollis and Flos chrysanthemi indici are almost identical and it is difficult to discriminate them, two-step identification was investigated via secondary derivative of the FTIR spectra. The bands at 1,656 and 1,515 cm(-1) corresponds to flavonoides in Flos rhododendri mollis and Flos chrysanthemi indici. In the secondary derivative of the FTIR spectrum of Flos chrysanthemi indici, characteristic bands of inulin were present at 1,163, 1,077, 1,026, 986 and 869 cm(-1), and therefore Flos chrysanthemi indici contained inulin as well. Tri-step identification was carried out for Flos rhododendri mollis and Flos chrysanthemi indici by means of comparing their 2D-IR correlation spectra in different wave number range. In the characteristic range of flavonoides (1,700-1,400 cm(-1)), Flos rhododendri mollis exhibited 3 obvious autopeaks, while 10 autopeaks were visualized in the 2D-IR correlation spectrum of Flos chrysanthemi indici Moreover, in the characteristic range of glucoside (1,250-900 cm(-1)), 10 and 9 autopeaks were present in the 2D-IR correlation spectra of Flos rhododendri mollis and Flos chrysanthemi indici, respectively. Therefore, the tri-step identification of FTIR is a time-saving; accurate, cost-saving and convenient method to effectively distinguish traditional Chinese medicines.
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Dargent, Felipe; Torres-Dowdall, Julián; Scott, Marilyn E.; Ramnarine, Indar; Fussmann, Gregor F.
2013-01-01
Predation and parasitism are two of the most important sources of mortality in nature. By forming groups, individuals can gain protection against predators but may increase their risk of being infected with contagious parasites. Animals might resolve this conflict by forming mixed-species groups thereby reducing the costs associated with parasites through a relative decrease in available hosts. We tested this hypothesis in a system with two closely related poeciliid fishes (Poecilia reticulata and Poecilia picta) and their host-specific monogenean ectoparasites (Gyrodactylus spp.) in Trinidad. Fish from three different rivers were sampled from single and mixed-species groups, measured and scanned for Gyrodactylus. The presence and abundance of Gyrodactylus were lower when fish of both species were part of mixed-species groups relative to single-species groups. This is consistent with the hypothesis that mixed-species groups provide a level of protection against contagious parasites. We discuss the importance of potentially confounding factors such as salinity and individual fish size. PMID:23437237
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Araújo, Márcio S; Perez, S Ivan; Magazoni, Maria Julia C; Petry, Ana C
2014-12-04
Phenotypic diversity among populations may result from divergent natural selection acting directly on traits or via correlated responses to changes in other traits. One of the most frequent patterns of correlated response is the proportional change in the dimensions of anatomical traits associated with changes in growth or absolute size, known as allometry. Livebearing fishes subject to predation gradients have been shown to repeatedly evolve larger caudal peduncles and smaller cranial regions under high predation regimes. Poecilia vivipara is a livebearing fish commonly found in coastal lagoons in the north of the state of Rio de Janeiro, Brazil. Similar to what is observed in other predation gradients, lagoons inhabited by P. vivipara vary in the presence of piscivorous fishes; contrary to other poeciliid systems, populations of P. vivipara vary greatly in body size, which opens the possibility of strong allometric effects on shape variation. Here we investigated body shape diversification among six populations of P. vivipara along a predation gradient and its relationship with allometric trajectories within and among populations. We found substantial body size variation and correlated shape changes among populations. Multivariate regression analysis showed that size variation among populations accounted for 66% of shape variation in females and 38% in males, suggesting that size is the most important dimension underlying shape variation among populations of P. vivipara in this system. Changes in the relative sizes of the caudal peduncle and cranial regions were only partly in line with predictions from divergent natural selection associated with predation regime. Our results suggest the possibility that adaptive shape variation among populations has been partly constrained by allometry in P. vivipara. Processes governing body size changes are therefore important in the diversification of this species. We conclude that in species characterized by substantial
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Banchio, Erika; Zygadlo, Julio; Valladares, Graciela R
2005-04-01
Plant tissues may show chemical changes following damage. This possibility was analyzed for Minthostachys mollis, a Lamiaceae native to Central Argentina with medicinal and aromatic uses in the region. Effects of mechanical damage on its two dominant monoterpenes, pulegone and menthone, were analyzed by perforating M. mollis leaves and then assessing essential oil composition at 24, 48, and 120 hr; emission of volatiles was also measured 24 and 48 hr after wounding. Mechanical damage resulted in an increase of pulegone and menthone concentration in M. mollis essential oil during the first 24 hr. These changes did not occur in the adjacent undamaged leaves, suggesting a lack of systemic response. Postwounding changes in the volatiles released from M. mollis damaged leaves were also detected, most noticeably showing an increase in the emission of pulegone. Inducible chemical changes in aromatic plants might be common and widespread, affecting the specific compounds on which commercial exploitation is based.
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Cruz-Vega, Delia Elva; Verde-Star, María Julia; Salinas-González, Noé; Rosales-Hernández, Bibiana; Estrada-García, Iris; Mendez-Aragón, Patricia; Carranza-Rosales, Pilar; González-Garza, María Teresa; Castro-Garza, Jorge
2008-04-01
Mycobacterium tuberculosis is a serious worldwide health threat, killing almost 2 million people per year. Alternative antimycobacterial drugs are urgently needed; studies have shown that medicinal plants traditionally used to treat respiratory diseases are a potential source of compounds to treat tuberculosis. This paper studied the antimycobacterial activity of 28 extracts from four different plant species that have been used in traditional Mexican medicine to treat tuberculosis. Bark and leaf crude extracts of Juglans regia L., Juglans mollis Engelm., Carya illinoensis (Wangenh) K. Koch and Bocconia frutescens showed in vitro anti-M. tuberculosis activity. Hexane bark extracts from C. illinoensis, J. mollis and J. regia were the most active with a minimal inhibitory concentration (MIC) of 31, 50 and 100 microg/mL, respectively. Ethanol bark extracts from C. illinoensis and J. mollis showed activity at 100 and 125 microg/mL, respectively. Leaf extracts had the lowest activity. Methanol and hexane leaves extracts from B. frutescens had a MIC of 125 microg/mL. None of the aqueous extracts showed antimycobacterial activity. (c) 2008 John Wiley & Sons, Ltd.
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Duckstein, Sarina M; Lotter, Eva M; Meyer, Ulrich; Lindequist, Ulrike; Stintzing, Florian C
2012-01-01
Acetone/water extracts from the leaves, including stalks, of Alchemilla vulgaris L. and A. mollis (Buser) Rothm. were investigated for their phenolic composition by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 24 and 27 compounds were detected for A. vulgaris and A. mollis, respectively. Pedunculagin and agrimoniin, as described in earlier reports for A. vulgaris, as well as other monomeric and oligomeric ellagitannins such as sanguiin H-10, castalagin/vescalagin, and galloyl-bis-hexahydroxydiphenoyl (HHDP) hexose constituted the major phenolic fraction of both plant species. Also, gallic and chlorogenic acids were found in both extracts. Interestingly, catechin and a procyanidin trimer were detected only in A. mollis. The flavonoid fraction comprised quercetin glucuronide as major compound in addition to several other quercetin glycosides. Most interestingly, a tentatively identified kaempferol glucuronide and a methylated quercetin glucuronide were exclusively found in A. mollis. Finally, the overall phenolic fingerprints of both Alchemilla species, harvested in May and August, i.e. at the beginning and the end of the flowering period, were compared. A general accumulation of phenolic constituents was observed later in the year, especially with regard to the ellagitannins.
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Duckstein, Sarina M; Lotter, Eva M; Meyer, Ulrich; Lindequist, Ulrike; Stintzing, Florian C
2013-01-01
Acetone/water extracts from the leaves, including stalks, of Alchemilla vulgaris L. and A. mollis (Buser) Rothm. were investigated for their phenolic composition by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 24 and 27 compounds were detected for A. vulgaris and A. mollis, respectively. Pedunculagin and agrimoniin, as described in earlier reports for A. vulgaris, as well as other monomeric and oligomeric ellagitannins such as sanguiin H-10, castalagin/vescalagin, and galloyl-bis-hexahydroxydiphenoyl (HHDP) hexose constituted the major phenolic fraction of both plant species. Also, gallic and chlorogenic acids were found in both extracts. Interestingly, catechin and a procyanidin trimer were detected only in A. mollis. The flavonoid fraction comprised quercetin glucuronide as major compound in addition to several other quercetin glycosides. Most interestingly, a tentatively identified kaempferol glucuronide and a methylated quercetin glucuronide were exclusively found in A. mollis. Finally, the overall phenolic fingerprints of both Alchemilla species, harvested in May and August, i.e. at the beginning and the end of the flowering period, were compared. A general accumulation of phenolic constituents was observed later in the year, especially with regard to the ellagitannins.
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Rasper, Michael; Nadjiri, Jonathan; Sträter, Alexandra S; Settles, Marcus; Laugwitz, Karl-Ludwig; Rummeny, Ernst J; Huber, Armin M
2017-06-01
To prospectively compare image quality and myocardial T 1 relaxation times of modified Look-Locker inversion recovery (MOLLI) imaging at 3.0 T (T) acquired with patient-adaptive dual-source (DS) and conventional single-source (SS) radiofrequency (RF) transmission. Pre- and post-contrast MOLLI T 1 mapping using SS and DS was acquired in 27 patients. Patient wise and segment wise analysis of T 1 times was performed. The correlation of DS MOLLI measurements with a reference spin echo sequence was analysed in phantom experiments. DS MOLLI imaging reduced T 1 standard deviation in 14 out of 16 myocardial segments (87.5%). Significant reduction of T 1 variance could be obtained in 7 segments (43.8%). DS significantly reduced myocardial T 1 variance in 16 out of 25 patients (64.0%). With conventional RF transmission, dielectric shading artefacts occurred in six patients causing diagnostic uncertainty. No according artefacts were found on DS images. DS image findings were in accordance with conventional T 1 mapping and late gadolinium enhancement (LGE) imaging. Phantom experiments demonstrated good correlation of myocardial T 1 time between DS MOLLI and spin echo imaging. Dual-source RF transmission enhances myocardial T 1 homogeneity in MOLLI imaging at 3.0 T. The reduction of signal inhomogeneities and artefacts due to dielectric shading is likely to enhance diagnostic confidence.
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Molly Pleskus (undergraduate student from Tufts University) visi
2018-02-08
3199: Molly Pleskus (undergraduate student from Tufts University) visited the MSFC electrostatic levitation (ESL) laboratory is support of Dr. Douglas Matson’s (Tufts University) grant, “Round Robin - Thermophysical Property Measurement†(NNX17AH41G). Ms. Pleskus is researching Inconel 718 in support of future experiments on the International Space Station (ISS).
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Pang, Y H; Zhao, J X; Du, W L; Li, Y L; Wang, J; Wang, L M; Wu, J; Cheng, X N; Yang, Q H; Chen, X H
2014-05-23
Leymus mollis (Trin.) Pilger (NsNsXmXm, 2n = 28), a wild relative of common wheat, possesses many traits that are potentially valuable for wheat improvement. In order to exploit and utilize the useful genes of L. mollis, we developed a multiple alien substitution line, 10DM50, from the progenies of octoploid Tritileymus M842-16 x Triticum durum cv. D4286. Genomic in situ hybridization analysis of mitosis and meiosis (metaphase I), using labeled total DNA of Psathyrostachys huashanica as probe, showed that the substitution line 10DM50 was a cytogenetically stable alien substitution line with 36 chromosomes from wheat and three pairs of Ns genome chromosomes from L. mollis. Simple sequence repeat analysis showed that the chromosomes 3D, 6D, and 7D were absent in 10DM50. Expressed sequence tag-sequence tagged sites analysis showed that new chromatin from 3Ns, 6Ns, and 7Ns of L. mollis were detected in 10DM50. We deduced that the substitution line 10DM50 was a multiple alien substitution line with the 3D, 6D, and 7D chromosomes replaced by 3Ns, 6Ns, and 7Ns from L. mollis. 10DM50 showed high resistance to leaf rust and significantly improved spike length, spikes per plant, and kernels per spike, which are correlated with higher wheat yield. These results suggest that line 10DM50 could be used as intermediate material for transferring desirable traits from L. mollis into common wheat in breeding programs.
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Experience-Dependent Color Constancy in Guppies (Poecilia reticulata)
Intskirveli, I. E.; Roinishvili, M. O.; Kezeli, A. R.
2002-01-01
We investigated the ability to recognize the color of surfaces in fish (Poecilia reticulata), bred from birth in conditions of artificial light with constant spectral content. The capacity for color constancy significantly deteriorated when compared that to the control group. Further alteration of lighting conditions and transfer into natural daylight conditions restored the suppressed function to its normal level. We suggest that the color constancy function belongs in the visual system-response functions, the full development of which requires the accumulation of individual visual experience. PMID:12757371
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Experience-dependent color constancy in guppies (Poecilia reticulata).
Intskirveli, I E; Roinishvili, M O; Kezeli, A R
2002-01-01
We investigated the ability to recognize the color of surfaces in fish (Poecilia reticulata), bred from birth in conditions of artificial light with constant spectral content. The capacity for color constancy significantly deteriorated when compared that to the control group. Further alteration of lighting conditions and transfer into natural daylight conditions restored the suppressed function to its normal level. We suggest that the color constancy function belongs in the visual system-response functions, the full development of which requires the accumulation of individual visual experience.
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Zhang, Yin Bo; Gao, Chen Hong; Qin, Hao
2018-04-01
Understanding the responses of the habitats of endangered species to climate change is of great significance for biodiversity conservation and the maintenance of the integrity of ecosystem function. In this study, the potential suitable distribution habitats of Elaeagnus mollis in Shanxi Province was simulated by the maximum entropy model, based on 73 occurrence field records and 35 environmental factors under the current climate condition. Moreover, with the Fifth Assessment Report of Intergovernmental Panel on Climate Change, the dynamics of distribution pattern was analyzed for E. mollis under different climate scenarios. The results showed that the area under the receiver operating characteristic curve (AUC) value was 0.987, indicating that the data fitted the model very well and that the prediction was highly reliable. Results from the Jackknife test showed that the main environmental variables affecting the E. mollis distribution were the precipitation seasonality, the range of annual temperature, annual mean temperature, isothermality, annual precipitation, and pH of topsoil, with the cumulative contribution reaching 94.8%. At present, the potential suitable habitats of E. mollis are mainly located in two regions, the southern of Lyuliang Mountain and Zhongtiao Mountain in Shanxi Province. Under different climate scenarios, the total suitable area of E. mollis would shrink in 2070s. In RCP 2.6 the suitable area would firstly increase and then decrease, while in RCP 4.5 and RCP 8.5 it would response sensitively and first decrease and then increase. Its spatial distribution in two suitable regions would show divergent responses to climate change. The distribution in southern Lyuliang Mountain would fluctuate slightly in latitudinal direction, while that in Zhongtiao Mountain would migrate along elevation.
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Bao, Y; Wang, J; He, F; Ma, H; Wang, H
2012-05-22
Leymus mollis, a perennial allotetraploid (2n = 4x = 28), known as American dune grass, is a wild relative of wheat that could be useful for cultivar improvement. Shannong0096, developed from interspecific hybridization between common wheat cv. Yannong15 and L. mollis, was analyzed with cytological procedures, genomic in situ hybridization, stripe-rust resistance screening and molecular marker analysis. We found that Shannong0096 has 42 chromosomes in the root-tip cells at mitotic metaphase and 21 bivalents in the pollen mother cells at meiotic metaphase I, demonstrating cytogenetic stability. Genomic in situ hybridization probed with total genomic DNA from L. mollis gave strong hybridization signals in the distal region of two wheat chromosome arms. A single dominant Yr gene, derived from L. mollis and temporarily designated as YrSn0096, was found on the long arm of chromosome 4A of Shannong0096. YrSn0096 should be a novel Yr gene because none of the previously reported Yr genes on chromosome 4A are related to L. mollis. This gene was found to be closely linked to the loci Xbarc236 and Xksum134 with genetic distances of 5.0 and 4.8 cM, respectively. Based on data from 267 F(2) plants of Yannong15/Huixianhong, the linkage map of YrSn0096, using the two molecular markers, was established in the order Xbarc236-YrSn0096-Xksum134. Shannong0096 appeared to be a unique wheat-L. mollis translocation with cryptic alien introgression. Cytogenetic stability, a high level of stripe-rust resistance, the common wheat background, and other positive agronomic traits make it a desirable donor for introducing novel alien resistance genes in wheat breeding programs, with the advantage of molecular markers that can be used to confirm introgression.
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Thirteen cases of proliferative lesions of the swimbladder were encountered in Japanese medaka Oryzias latipes and guppy Poecilia reticulata from about 10,000 medaka and 5,000 guppies used in carcinogenicity tests and histologically examined. Two of the four cases from medaka and...
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Who is 'Molly'? MDMA adulterants by product name and the impact of harm-reduction services at raves.
Saleemi, Sarah; Pennybaker, Steven J; Wooldridge, Missi; Johnson, Matthew W
2017-08-01
Methylenedioxymethamphetamine (MDMA), often sold as 'Ecstasy' or 'Molly', is commonly used at music festivals and reported to be responsible for an increase in deaths over the last decade. Ecstasy is often adulterated and contains compounds that increase morbidity and mortality. While users and clinicians commonly assume that products sold as Molly are less-adulterated MDMA products, this has not been tested. Additionally, while pill-testing services are sometimes available at raves, the assumption that these services decrease risky drug use has not been studied. This study analyzed data collected by the pill-testing organization, DanceSafe, from events across the United States from 2010 to 2015. Colorimetric reagent assays identified MDMA in only 60% of the 529 samples collected. No significant difference in the percentage of samples testing positive for MDMA was determined between Ecstasy and Molly. Individuals were significantly less likely to report intent to use a product if testing did not identify MDMA (relative risk (RR) = 0.56, p = 0.01). Results suggest that Molly is not a less-adulterated substance, and that pill-testing services are a legitimate harm-reduction service that decreases intent to consume potentially dangerous substances and may warrant consideration by legislators for legal protection. Future research should further examine the direct effects of pill-testing services and include more extensive pill-testing methods.
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Souza, Helena A V; Collevatti, Rosane G; Lemos-Filho, José P; Santos, Fabrício R; Lovato, Maria Bernadete
2012-03-01
Microsatellite markers were developed for Dimorphandra mollis (Leguminosae), a widespread tree in the Brazilian cerrado (a savanna-like vegetation). Microsatellite markers were developed from an enriched library. The analyses of polymorphism were based on 56 individuals from three populations. Nine microsatellite loci were polymorphic, with the number of alleles per locus ranging from three to 10 across populations. The observed and expected heterozygosities per locus and population ranged from 0.062 to 0.850 and from 0.062 to 0.832, respectively. These microsatellites provide an efficient tool for population genetics studies and will be used to assess the genetic diversity and spatial genetic structure of D. mollis.
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Reflections on Integrative Curriculum: A Conversation with Camille Barr and Molly Maloy.
ERIC Educational Resources Information Center
Powell, Richard R.
1999-01-01
Interviews two principals of middle schools using integrated curriculum: Molly Maloy of Carver Academy, Waco, Texas, and Camille Barr of Brown Barge Middle School, Pensacola, Florida. Considers issues of transforming theory into daily practice, reforming and developing curriculum, and building teacher leadership. Provides backgrounds on the…
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Using data from an encounter sampler to model fish dispersal
Obaza, A.; DeAngelis, D.L.; Trexler, J.C.
2011-01-01
A method to estimate speed of free-ranging fishes using a passive sampling device is described and illustrated with data from the Everglades, U.S.A. Catch per unit effort (CPUE) from minnow traps embedded in drift fences was treated as an encounter rate and used to estimate speed, when combined with an independent estimate of density obtained by use of throw traps that enclose 1 m2 of marsh habitat. Underwater video was used to evaluate capture efficiency and species-specific bias of minnow traps and two sampling studies were used to estimate trap saturation and diel-movement patterns; these results were used to optimize sampling and derive correction factors to adjust species-specific encounter rates for bias and capture efficiency. Sailfin mollies Poecilia latipinna displayed a high frequency of escape from traps, whereas eastern mosquitofish Gambusia holbrooki were most likely to avoid a trap once they encountered it; dollar sunfish Lepomis marginatus were least likely to avoid the trap once they encountered it or to escape once they were captured. Length of sampling and time of day affected CPUE; fishes generally had a very low retention rate over a 24 h sample time and only the Everglades pygmy sunfish Elassoma evergladei were commonly captured at night. Dispersal speed of fishes in the Florida Everglades, U.S.A., was shown to vary seasonally and among species, ranging from 0.05 to 0.15 m s-1 for small poeciliids and fundulids to 0.1 to 1.8 m s-1 for L. marginatus. Speed was generally highest late in the wet season and lowest in the dry season, possibly tied to dispersal behaviours linked to finding and remaining in dry-season refuges. These speed estimates can be used to estimate the diffusive movement rate, which is commonly employed in spatial ecological models.
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[Chemical constituents of Cocculus orbiculatus var. mollis root].
Liao, Jing; Lei, Yu; Wang, Jian-Zhong
2014-02-01
To study the chemical constituents in the root of Cocculus orbiculatus var. mollis. The compounds were isolated by silica gel chromatography, their structures were established by spectroscopic methods. Eleven compounds were isolated and identified as wattisine A (I), O-methylcocsoline (II), (+) cocsoline (III), (+) cocsuline (IV), magnoflorine (V), sino-coculine (VI), isosinococuline (VII), (-) coclaurine (VIII), daucosterol (IX), beta-sitosterol (X) and 1-oleioyl-3-(9Z, 12Z-arachoyl) glycerol (XI). Compound I is isolated from this genus for the first time,and compound II - XI are isolated from this plant for the first time.
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Bizerril, M X A; Rodrigues, F H G; Hass, A
2005-08-01
Fruit phenology observations and consumption of Dimorphandra mollis (Leguminosae) were analyzed during seven months in an area of cerrado stricto sensu. We analysed 81 fecal samples collected at six different places of lowland tapirs (Tapirus terrestris) in central Brazilian cerrado. In addition, from the feces of five tapirs at the Brasília Zoo to which fruit had been offered, seeds were collected and used in germination tests. The results suggest that the tapir is an important fruit consumer and a potential seed disperser of D. mollis. In the field, however, fruit consumption was found to be very low, probably because of both fruit palatability and the low density of frugivores, especially tapirs. The possibility that the original dispersal agents of D. mollis seeds belonged to the South American Pleistocene megafauna is discussed.
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Yan, Wenying; Han, Qingjie; Guo, Panpan; Wang, Chunying; Zhang, Zijian
2016-01-01
Abri Herba has remarkable properties, such as cleanup heat detoxification, dampness and activating blood circulation to dissipate blood stasis; as a result, it has been applied to treat acute or chronic hepatitis and mastitis. Abri mollis Herba is often used as Abri Herba. Hierarchical cluster analysis (HCA) was applied to compare the similarities and differences of the chemical compositions in the two types of medicinal materials. To establish a high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) method for the simultaneous analysis of 15 flavonoids, two phenolic acids and three alkaloids in Abri Herba and Abri mollis Herba. The chromatographic separation was performed on a C18 column with a mobile phase of methanol (A), acetonitrile (B) and 0.5‰ acetic acid in water (C) using gradient elution. The detection of the target compounds was performed in multiple-reaction monitoring (MRM) mode using a hybrid quadrupole linear ion trap mass spectrometer equipped with positive/negative ion-switching electrospray ionisation (ESI) source. The developed method is reliable, sensitive and specific. In addition, the method has been successfully applied to differentiate 15 batches of Abri Herba and 27 batches of Abri mollis Herba stems. Furthermore, a comparison of the contents among stems, roots and leaves from the same strain in seven batches of Abri mollis Herba and four batches of Abri Herba has also been performed. HPLC-MS/MS method is sensitive and selective and can be suitable for the reliable quality control of Abri mollis Herba and Abri Herba. Copyright © 2015 John Wiley & Sons, Ltd.
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Yang, Xiaofei; Li, Xin; Wang, Changyou; Chen, Chunhuan; Tian, Zengrong; Ji, Wanquan
2017-12-01
A common wheat - Leymus mollis (2n = 4x = 28, NsNsXmXm) double monosomic addition line, M11003-4-3-8/13/15 (2n = 44 = 42T.a + L.m2 + L.m3), with stripe rust resistance was developed (where T.a represents Triticum aestivum chromosome, L.m represents L. mollis chromosome, and L.m2/3 represents L. mollis chromosome of homoeologous groups 2 and 3). The progenies of line M11003-4-3-8/13/15 were characterized by cytological observation, specific molecular markers, fluorescence in situ hybridization (FISH), and genomic in situ hybridization (GISH). Among the progenies, there existed five different types (I, II, III, IV, and V) of chromosome constitution, the formulas of which were 2n = 44 = 42T.a + 1L.m2 + 1L.m3, 2n = 43 = 42T.a + 1L.m2, 2n = 43 = 42T.a + 1L.m3, 2n = 42 = 42T.a, and 2n = 44 = 42T.a + 2L.m2, respectively. Field disease screening showed that types I and III showed high resistance to stripe rust, while types II, IV, and V were susceptible. Leymus mollis was almost immune to stripe rust, whereas the wheat parent, cultivar 7182, was susceptible. Therefore, we concluded that the stripe rust resistance originated from L. mollis. These various lines could be further fully exploited as important disease resistance materials to enrich wheat genetic resources.
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Evaluation of the carcinogenic effects of furazolidone and its metabolites in two fish species.
Auro, A; Sumano, H; Ocampo, L; Barragán, A
2004-01-01
The major metabolite from the use of furazolidone (FZD) in mammals, birds and fish is 2,3-dihydro-3-cyanomethyl-2-hydroxy-5-nitro-1alpha, 2-di(2-oxo-oxazolidin-3-yl)iminomethyl-furo[2,3-beta]furan, also called 3-amine-2-oxazolidone (AOZ). A minor metabolite was identified as N-(5-amine-2-furfuryliden)-3-amine-2-oxazolidone (FOZ). To assess the potential carcinogenicity of FZD and the metabolic mixture of AOZ/FOZ, 11 mg FZD/kg feed/day was fed for 12 weeks to mollies (Poecilia formosa), an ornamental fish species prone to develop tumors. The rate of tumors was quantified and defined both in mollies and their offspring. Then, some fish was made into fishmeal and incorporated into fish food at 500 g of meal/kg of food and fed to other mollies for 12 weeks. The rate of tumors was assessed. A similar trial design was carried out in tilapia fish (Oreochromis niloticus) by adding 50 mg FZD/kg to the feed for 90 days. All animals were placed in glass fishponds under controlled laboratory conditions. Each week, a significant biomass was collected from both groups to assess the macroscopic and histopathological changes. All mollies developed melanohistiocytomic tumors in the liver and other organs. Offspring from surviving mollie females stimulated to breed showed no changes compared to control animals. None of the mollies fed with the mollie-meal food contaminated with AOZ/FOZ developed tumors. Neither tilapia medicated with FZD nor tilapia fed with tilapia-meal contaminated with AOZ/FOZ developed tumors. These results do not support the established viewpoint that FZD must be banned from trophic chains based on its potential carcinogenic properties.
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Banchio, Erika; Zygadlo, Julio; Valladares, Graciela R
2005-08-24
Plants display a diverse array of inducible changes in secondary metabolites following insect herbivory. Herbivores differ in their feeding behavior, physiology, and mode of attachment to the leaf surface, and such variations might be reflected in the induced responses of damaged plants. Induced changes were analyzed for Minthostachys mollis, a Lamiaceae with medicinal and aromatic uses, and four species of folivore insects with different feeding habits (chewing, scraping, sap-sucking, and puncturing). In M. mollis leaves experimentally exposed to the insects, levels of the two dominant monoterpenes pulegone and menthone were assessed 24 and 48 h after wounding. Menthone content generally decreased in the essential oil of damaged leaves, whereas pulegone concentration increased in all treatments. These changes occurred also in the adjacent undamaged leaves, suggesting a systemic response. The relatively uniform response to different kinds of damage could be attributable to the presence of such a strongly active compound as pulegone in the essential oil of M. mollis. The effects of wounding on essential oil concentration may be significant from a commercial point of view.
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Comparative study of infection with Tetrahymena of different ornamental fish species.
Sharon, G; Pimenta Leibowitz, M; Chettri, J Kumar; Isakov, N; Zilberg, D
2014-01-01
Tetrahymena is a ciliated protozoan that can infect a wide range of fish species, although it is most commonly reported in guppies (Poecilia reticulata). The aim of this study was to compare the susceptibility to infection with Tetrahymena of five different ornamental fish species from two different super orders. The species examined were platy (Xiphophorus), molly (Poecilia sphenops) and angelfish (Pterophyllum scalare) of the Acanthopterygii super order (which also includes guppies) and goldfish (Carassius auratus auratus) and koi carp (Cyprinus carpio) of the Ostariophysi super order. These two super orders are phylogenetically distant from each other. Infection with Tetrahymena resulted in parasite invasion of internal organs, skin and muscle in all fish species. A relatively strong inflammatory response was observed in infected goldfish and koi, with negligible response in fish species of the Acanthopterygii super order. Guppies were the most susceptible to Tetrahymena infection, exhibiting a mortality rate of 87% and 100% in two separate experiments. A high mortality rate was also observed in platy (77%), while that of molly and angelfish was significantly lower (23% and 33%, respectively). Goldfish and koi carp were less susceptible to infection compared with guppies (24% and 59% mortality, respectively). Immunization studies revealed that the Tetrahymena are immunogenic, since infection of koi carp increased their Tetrahymena immobilization response by approximately three-fold at 3 weeks post infection, while immunization with Tetrahymena plus adjuvant increased their immobilization response by approximately 30-fold. Copyright © 2013 Elsevier Ltd. All rights reserved.
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A Tribute to the Life and Accomplishments of Molly K. Macauley
NASA Astrophysics Data System (ADS)
Escobar, V. M.; Kenney, M. A.; Bernknopf, R.; Pearlman, J.; Gail, W. B.; Friedl, L.
2016-12-01
Molly Macauley was an expert in space policy and the socioeconomic benefits of Earth observations. She was Vice President for Research and a Senior Fellow at Resources for the Future, where she worked as an economist for over 20 years. Sadly, Dr. Macauley tragically passed away in July 2016. This talk will pay tribute to her accomplishments by sharing how she shaped the GEOValue community and the way we think about the value of satellite data and products.
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that are economical, sensitive, and scientifically acceptable. Among small fish models, the Japanese medaka (Oryzias latipes) is preeminent for investigating effects of carcinogenic and/or toxic waterborne hazards to humans. The guppy (Poecilia reticulata), although less widely u...
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Cytotoxic Compounds from Brucea mollis
Tung, Mai Hung Thanh; Đuc, Ho Viet; Huong, Tran Thu; Duong, Nguyen Thanh; Phuong, Do Thi; Thao, Do Thi; Tai, Bui Huu; Kim, Young Ho; Bach, Tran The; Cuong, Nguyen Manh
2013-01-01
Ten compounds, including soulameanone (1), isobruceine B (2), 9-methoxy-canthin-6-one (3), bruceolline F (4), niloticine (5), octatriacontan-1-ol (6), bombiprenone (7), α-tocopherol (8), inosine (9), and apigenin 7-O-β-D-glucopyranoside (10), were isolated from the leaves, stems, and roots of Brucea mollis Wall. ex Kurz. Their structures were determined using one-and two-dimensional NMR spectroscopy and mass spectrometry. All compounds were evaluated for their cytotoxic activity against KB (human carcinoma of the mouth), LU-1 (human lung adenocarcinoma), LNCaP (human prostate adeno-carcinoma), and HL-60 (human promyelocytic leukemia) cancer cell lines. Compound 2 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values of 0.39, 0.40, 0.34, and 0.23 μg/mL, respectively. In addition, compounds 3 and 5 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values around 1–4 μg/mL. Compounds 9-methoxycanthin-6-one (3) and niloticine (5) have been discovered for the first time from the Brucea genus. PMID:24106661
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Mora, Flor D; Araque, María; Rojas, Luis B; Ramirez, Rosslyn; Silva, Bladimiro; Usubillaga, Alfredo
2009-07-01
Chemical constituents of the essential oil from the leaves of Minthostachys mollis (Kunth) Griseb Vaught var. mollis collected in January 2008 at Tuñame, Trujillo State, Venezuela, were separated and identified by GC-MS analysis. The essential oil was obtained by hydrodistillation and thirteen components (98.5% of the sample) were identified by comparison with the Wiley GC-MS library data base. The two major components were pulegone (55.2%) and trans-menthone (31.5%). The essential oil showed a significant inhibitory effect against Gram-positive and Gram-negative bacteria, especially Bacillus subtilis and Salmonella typhi (4 microg/mL).
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McClintock, J B; Baker, B J; Hamann, M T; Yoshida, W; Slattery, M; Heine, J N; Bryan, P J; Jayatilake, G S; Moon, B H
1994-10-01
The common bright yellow antarctic lamellarian gastropodMarseniopsis mollis was examined for the presence of defensive chemistry. Proton nuclear magnetic resonance (NMR) spectroscopy indicated that a major component of ethanolic extracts purified by reversed-phase column chromatography was homarine. Further high-performance liquid chromatography (HPLC) analysis of the mantle, foot, and viscera verified the presence of homarine in all body tissues at concentrations ranging from 6 to 24 mg/g dry tissue. A conspicuous macroinvertebrate predator of the shallow antarctic benthos, the sea starOdontaster validus, always rejected live individuals ofM. mollis, while readily feeding on pieces of fish tail muscle. Filter paper disks treated with shrimp elicited a broad range of feeding behaviors in the sea starO. validus (movement of disc to mouth, extrusion of cardiac stomach, humped feeding posture). Shrimp disks treated with homarine (0.4 and 4 mg/disk) were rejected byO. validus significantly more frequently than control disks treated with solvent carrier and shrimp or shrimp alone. The highest concentration of homarine tested not only caused feeding deterrence, but in several sea stars a flight response was noted. Homarine was not detected in the tunic of the antarctic ascidianCnemidocarpa verrucosa, a presumed primary prey ofM. mollis. Nonetheless, crude extracts of the epizooites that foul the tunic (primarily the bryozoans and hydroids) contain homarine, suggestingM. mollis may ingest and derive its chemistry from these organisms. This appears to be only the third example of chemical defense in a member of the Order Mesogastropoda. As the vestigial internalized shell ofM. mollis is considered a primitive condition, the findings of this study lend support to the hypothesis that chemical defense evolved prior to shell loss in shell-less gastropods.
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Acute toxicity and effects analysis of endosulfan sulfate to freshwater fish species.
Carriger, John F; Hoang, Tham C; Rand, Gary M; Gardinali, Piero R; Castro, Joffre
2011-02-01
Endosulfan sulfate is a persistent environmental metabolite of endosulfan, an organochlorine insecticide-acaricide presently registered by the United States Environmental Protection Agency. There is, however, limited acute fish toxicity data for endosulfan sulfate. This study determines the acute toxicity (LC₅₀s and LC₁₀s) of endosulfan sulfate to three inland Florida native fish species (mosquitofish [Gambusia affinis]; least killifish [Heterandria formosa]; and sailfin mollies [Poecilia latipinna]) as well as fathead minnows (Pimephales promelas). Ninety-six-h acute toxicity tests were conducted with each fish species under flow-through conditions. For all of the above-mentioned fish species, 96-h LC₅₀ estimates ranged from 2.1 to 3.5 μg/L endosulfan sulfate. The 96-h LC₁₀ estimates ranged from 0.8 to 2.1 μg/L endosulfan sulfate. Of all of the fish tested, the least killifish appeared to be the most sensitive to endosulfan sulfate exposure. The above-mentioned data were combined with previous acute toxicity data for endosulfan sulfate and freshwater fish for an effects analysis. The effects analysis estimated hazardous concentrations expected to exceed 5, 10, and 50% of the fish species' acute LC₅₀ or LC₁₀ values (HC₅, HC₁₀, and HC₅₀). The endosulfan sulfate freshwater-fish acute tests were also compared with the available freshwater-fish acute toxicity data for technical endosulfan. Technical endosulfan is a mixture of α- and β-endosulfan. The LC₅₀s had a wider range for technical endosulfan, and their distribution produced a lower HC₁₀ than for endosulfan sulfate. The number of freshwater-fish LC₅₀s for endosulfan sulfate is much smaller than the number available for technical endosulfan, reflecting priorities in examining the toxicity of the parent compounds of pesticides. The toxicity test results and effects analyses provided acute effect values for endosulfan sulfate and freshwater fish that might be applied
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Antioxidant, phenolic and antifungal profiles of Acanthus mollis (Acanthaceae).
Jara, Carlos; Leyton, Miguel; Osorio, Mauricio; Silva, Viviana; Fleming, Francisco; Paz, Marilyn; Madrid, Alejandro; Mellado, Marco
2017-10-01
Acanthus mollis is used as ornamental and medicinal plant. The ethnopharmacology reports indicate that extracts have anti-inflammatory activity. Phytoconstituents profile was evaluated by estimating the content of anthraquinones, flavonoids and phenols. In addition, the antioxidant activity was evaluated using four methods: Hydrogen atoms transfer (TRAP, ORAC and DPPH assays), and single electron transfer (FRAP assay). Finally, antifungal activity was determined by the M27-A2 test. The results shown that ethanol extracts have the highest concentration of phenols, anthraquinones and flavonoids. Total antioxidant capacity, extracts of ethyl acetate and ethanol are those with the highest activity, which correlates strongly with the presence of phenols. The antifungal activity measured in various strains of Candida is concentrated in ethyl acetate extracts of flower and leaf ethanol, a phenomenon may be related to antioxidant activity.
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Morales-Del-Rio, Juan Alfredo; Gutiérrez-Lomelí, Melesio; Robles-García, Miguel Angel; Aguilar, Jose Antonio; Lugo-Cervantes, Eugenia; Guerrero-Medina, Pedro Javier; Ruiz-Cruz, Saul; Cinco-Moroyoqui, Francisco J.; Wong-Corral, Francisco J.; Del-Toro-Sánchez, Carmen Lizette
2015-01-01
Vitex mollis is used in traditional Mexican medicine for the treatment of some ailments. However, there are no studies on what happens to the anti-inflammatory activity or antioxidant properties and total phenolic content of leaves and stem extracts of Vitex mollis during the digestion process; hence, this is the aim of this work. Methanolic, acetonic, and hexanic extracts were obtained from both parts of the plant. Extract yields and anti-inflammatory activity (elastase inhibition) were measured. Additionally, changes in antioxidant activity (DPPH and ABTS) and total phenols content of plant extracts before and after in vitro digestion were determined. The highest elastase inhibition to prevent inflammation was presented by hexanic extracts (leaf = 94.63% and stem = 98.30%). On the other hand, the major extract yield (16.14%), antioxidant properties (ABTS = 98.51% and DPPH = 94.47% of inhibition), and total phenols (33.70 mg GAE/g of dried sample) were showed by leaf methanolic extract. Finally, leaf and stem methanolic extracts presented an antioxidant activity increase of 35.25% and 27.22%, respectively, in comparison to their initial values after in vitro digestion process. All samples showed a decrease in total phenols at the end of the digestion. These results could be the basis to search for new therapeutic agents from Vitex mollis. PMID:26451153
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Souza, H A V; Muller, L A C; Brandão, R L; Lovato, M B
2012-03-22
Dimorphandra mollis (Leguminosae), known as faveiro and fava d'anta, is a tree that is widely distributed throughout the Brazilian Cerrado (a savanna-like biome). This species is economically valuable and has been extensively exploited because its fruits contain the flavonoid rutin, which is used to produce medications for human circulatory diseases. Knowledge about its genetic diversity is needed to guide decisions about the conservation and rational use of this species in order to maintain its diversity. DNA extraction is an essential step for obtaining good results in a molecular analysis. However, DNA isolation from plants is usually compromised by excessive contamination by secondary metabolites. DNA extraction of D. mollis, mainly from mature leaves, results in a highly viscous mass that is difficult to handle and use in techniques that require pure DNA. We tested four protocols for plant DNA extraction that can be used to minimize problems such as contamination by polysaccharides, which is more pronounced in material from mature leaves. The protocol that produced the best DNA quality initially utilizes a sorbitol buffer to remove mucilaginous polysaccharides. The macerated leaf material is washed with this buffer until there is no visible mucilage in the sample. This protocol is adequate for DNA extraction both from young and mature leaves, and could be useful not only for D. mollis but also for other species that have high levels of polysaccharide contamination during the extraction process.
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Cha, Dong H; Powell, Thomas H Q; Feder, Jeffrey L; Linn, Charles E
2018-06-20
A new blend of volatiles was identified for the fruit of downy red hawthorn, Crataegus mollis, that is attractive to Rhagoletis pomonella flies infesting this host in the northeastern USA. The new blend was as attractive as the previously identified mixture but is more complex in the number of odorants (six in the old versus ten in the new) and differs significantly in the ratio of three volatiles, 3-methylbutan-1-ol, butyl hexanoate, and dihydro-β-ionone, that are common to both blends and exerted agonist or antagonist effects on behavior in a flight tunnel assay. However, behavioral results with the old and new northern hawthorn blends, as well as modified blends with substituted ratios of 3-methylbutan-1-ol, butyl hexanoate, dihydro-β-ionone, indicated that the 'agonist' or 'antagonist' effects of these volatiles depended on the ratio, or balance of compounds within the blend. In addition, the new blend contains a number of esters identified from the headspace of domesticated apple, Malus domestica, that are attractive to apple-origin R. pomonella, and present in the five other blends from southern hawthorns, including the southern C. mollis var. texana blend, but are not part of the previously identified blend from northern C. mollis fruit. This finding supports the hypothesis that in addition to providing specificity to the odor blends of the northern and southern hawthorn populations, the presence of the significant amounts of ester compounds in the new northern hawthorn blend might have provided a source of standing variation that could help explain the shift in host preference by C. mollis-infesting flies to introduced apple in the mid-1800's.
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Aerial Jumping in the Trinidadian Guppy (Poecilia reticulata)
Soares, Daphne; Bierman, Hilary S.
2013-01-01
Many fishes are able to jump out of the water and launch themselves into the air. Such behavior has been connected with prey capture, migration and predator avoidance. We found that jumping behavior of the guppy Poecilia reticulata is not associated with any of the above. The fish jump spontaneously, without being triggered by overt sensory cues, is not migratory and does not attempt to capture aerial food items. Here, we use high speed video imaging to analyze the kinematics of the jumping behavior P. reticulata. Fish jump from a still position by slowly backing up while using its pectoral fins, followed by strong body trusts which lead to launching into the air several body lengths. The liftoff phase of the jump is fast and fish will continue with whole body thrusts and tail beats, even when out of the water. This behavior occurs when fish are in a group or in isolation. Geography has had substantial effects on guppy evolution, with waterfalls reducing gene flow and constraining dispersal. We suggest that jumping has evolved in guppies as a behavioral phenotype for dispersal. PMID:23613883
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4α-Methylated steroids with cytotoxic activity from the soft coral Litophyton mollis.
Zovko Končić, Marijana; Ioannou, Efstathia; Sawadogo, Wamtinga Richard; Abdel-Razik, Ayman F; Vagias, Constantinos; Diederich, Marc; Roussis, Vassilios
2016-11-01
Seven new (1-3, 5 and 8-10) and three previously reported (4, 6 and 7) 4α-methylated steroids were isolated from the organic extract of the gorgonian Litophyton mollis. The structures and the relative configurations of the isolated natural products were determined on the basis of extensive analyses of their NMR and MS data. Metabolites 1 and 5-8 exhibited cytotoxic activity against K562 human chronic myelogenous leukemia cells with IC 50 values below 10μM, while at the same time displaying low toxicity against healthy PBMCs. Copyright © 2016 Elsevier Inc. All rights reserved.
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MDMA (ecstasy/molly) use among African Americans: The perceived influence of hip-hop/rap music.
Rigg, Khary K; Estreet, Anthony T
2018-02-12
Over the past two decades, the demographic profile of MDMA (ecstasy/molly) users has changed. In particular, African American MDMA use has risen in some cities. One explanation of this new trend is the drug's recent popularity (as molly) in hip-hop/rap (HHR) music. Several top rappers endorse the drug as a way to have fun or get women "loose." There are currently no studies, however, that investigate the extent to which African American MDMA users listen to HHR music or the influence that these pro-MDMA messages have on their use of the drug. To address this gap, the current study used survey data to (a) identify the extent to which HHR music is listened to by African American MDMA users and (b) assess the perceived influence of HHR music on their decision to begin using. Qualitative interview data are also presented to contextualize the influence of these messages on their use of MDMA. The findings of this study suggest that African American MDMA users are high consumers of HHR music and that pro-MDMA messages in HHR music are influencing their expectations of the drug and their decision to initiate use. These findings add to the limited amount of research on African American MDMA use and have the potential to inform future interventions.
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Hwang, Eunson; Ngo, Hien T T; Seo, Seul A; Park, Bom; Zhang, Mengyang; Yi, Tae-Hoo
2018-01-15
Alchemilla mollis (lady's mantle) is a common ingredient in skin care products. However, the protective mechanism of A. mollis against skin problems has not been elucidated. This study was to investigate the effects of A. mollis ethanolic extract (AM) on UVB-irradiated normal human dermal fibroblasts (NHDF) and hairless mice. The in vitro anti-photoaging effect of AM was performed in NHDFs. The antioxidant activities were assessed through DPPH, ABTS, and reactive oxygen species (ROS) assays. Matrix metalloproteinase 1 (MMP-1), IL-6, procollagen type I, and transforming growth factor-β1 (TGF-β1) were measured by kits. The protein levels of p-c-Jun, p-c-Fos, Nrf2, NQO-1, HO-1, nuclear NFATc1 and cytosolic p-NFATc1 were evaluated by western blotting. In in vivo, H&E and Masson's trichrome staining were carried out. Skin texture was analyzed using the roughness parameters. The expression of MMP-1, procollagen type I, TGF-β1 and elastin were measured by western blot. AM included gallic acid as an active constituent. AM exhibited a strong antioxidant effect by inhibiting DPPH and ABTS free radicals, as well as ROS production. It was also found to upregulate transforming growth factor β1, type I procollagen and elastin expression, and to downregulate matrix metalloproteinase-1 and interleukin-6 expression in AM-treated NHDFs under UVB irradiation. These effects were attributed to AP-1 and Nrf2/ARE signaling pathways. Significantly, it was demonstrated that AM regulated the UVB-induced NFATc1 dephosphorylation in nucleus. Based on dietary data, AM was effective for the prevention of wrinkle formation, skin thickening, water loss, and erythema in UVB-exposed mouse skin. Our data indicate that A. mollis provides protection from UVB exposure in both hairless mice skin in vivo and NHDFs in vitro. AM might therefore be useful as a cosmetic material and functional food for the prevention of UVB-induced human skin photoaging. Copyright © 2017 Elsevier GmbH. All rights
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Krebs, Justin M.; Bell, Susan S.; McIvor, Carole C.
2014-01-01
To assess the potential influence of coastal development on habitat quality for estuarine nekton, we characterized body condition and reproduction for common nekton from tidal tributaries classified as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). We then evaluated these metrics of nekton performance, along with several abundance-based metrics and community structure from a companion paper (Krebs et al. 2013) to determine which metrics best reflected variation in land-use and in-stream habitat among tributaries. Body condition was not significantly different among undeveloped, industrial, and man-made tidal tributaries for six of nine taxa; however, three of those taxa were in significantly better condition in urban compared to undeveloped tributaries. Palaemonetes shrimp were the only taxon in significantly poorer condition in urban tributaries. For Poecilia latipinna, there was no difference in body condition (length–weight) between undeveloped and urban tributaries, but energetic condition was significantly better in urban tributaries. Reproductive output was reduced for both P. latipinna (i.e., fecundity) and grass shrimp (i.e., very low densities, few ovigerous females) in urban tributaries; however a tradeoff between fecundity and offspring size confounded meaningful interpretation of reproduction among land-use classes for P. latipinna. Reproductive allotment by P. latipinna did not differ significantly among land-use classes. Canonical correspondence analysis differentiated urban and non-urban tributaries based on greater impervious surface, less natural mangrove shoreline, higher frequency of hypoxia and lower, more variable salinities in urban tributaries. These characteristics explained 36 % of the variation in nekton performance, including high densities of poeciliid fishes, greater energetic condition of sailfin mollies, and low densities of several common nekton and economically important taxa from urban tributaries
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Schulz-Mirbach, Tanja; Riesch, Rüdiger; García de León, Francisco J; Plath, Martin
2011-12-01
Our study was designed to evaluate if, and to what extent, restrictive environmental conditions affect otolith morphology. As a model, we chose two extremophile livebearing fishes: (i) Poecilia mexicana, a widespread species in various Mexican freshwater habitats, with locally adapted populations thriving in habitats characterized by the presence of one (or both) of the natural stressors hydrogen sulphide and darkness, and (ii) the closely related Poecilia sulphuraria living in a highly sulphidic habitat (Baños del Azufre). All three otolith types (lapilli, sagittae, and asterisci) of P. mexicana showed a decrease in size ranging from the non-sulphidic cave habitat (Cueva Luna Azufre), to non-sulphidic surface habitats, to the sulphidic cave (Cueva del Azufre), to sulphidic surface habitats (El Azufre), to P. sulphuraria. Although we found a distinct differentiation between ecotypes with respect to their otolith morphology, no clear-cut pattern of trait evolution along the two ecological gradients was discernible. Otoliths from extremophiles captured in the wild revealed only slight similarities to aberrant otoliths found in captive-bred fish. We therefore hypothesize that extremophile fishes have developed coping mechanisms enabling them to avoid aberrant otolith growth - an otherwise common phenomenon in fishes reared under stressful conditions. Copyright © 2011 Elsevier GmbH. All rights reserved.
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Flash Extraction and Physicochemical Characterization of Oil from Elaeagnus mollis Diels Seeds.
Kan, Lina; Wang, Lin; Ding, Qingzhen; Wu, Yanwen; Ouyang, Jie
2017-04-03
A flash extraction method was used to isolate Elaeagnus mollis oil (EMO). The optimal extraction parameters, sample/solvent ratio and extraction temperature, were determined to be 1:10 (g/mL) and 40°C, respectively. Especially, the extraction yield reached 49.30% when the extraction time was as short as 2 min. No obvious difference was observed in fatty acid composition, iodine value, saponification number, total phenolic content and tocopherol content between flash-extracted EMO and Soxhlet-extracted EMO, but their physicochemical values were lower than those of cold-pressed EMO. Cold-pressed EMO had higher oxidation stability, DPPH (1-diphenyl-2-picrylhydrazyl) and hydroxyl radical-scavenging activities than flash-extracted EMO and Soxlet extracted EMO. The flash extraction is demonstrated to be an alternative, efficient method for the vegetable oil production.
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Sussman, Marshall S; Yang, Issac Y; Fok, Kai-Ho; Wintersperger, Bernd J
2016-06-01
The Modified Look-Locker Inversion Recovery (MOLLI) technique is used for T1 mapping in the heart. However, a drawback of this technique is that it requires lengthy rest periods in between inversion groupings to allow for complete magnetization recovery. In this work, a new MOLLI fitting algorithm (inversion group [IG] fitting) is presented that allows for arbitrary combinations of inversion groupings and rest periods (including no rest period). Conventional MOLLI algorithms use a three parameter fitting model. In IG fitting, the number of parameters is two plus the number of inversion groupings. This increased number of parameters permits any inversion grouping/rest period combination. Validation was performed through simulation, phantom, and in vivo experiments. IG fitting provided T1 values with less than 1% discrepancy across a range of inversion grouping/rest period combinations. By comparison, conventional three parameter fits exhibited up to 30% discrepancy for some combinations. The one drawback with IG fitting was a loss of precision-approximately 30% worse than the three parameter fits. IG fitting permits arbitrary inversion grouping/rest period combinations (including no rest period). The cost of the algorithm is a loss of precision relative to conventional three parameter fits. Magn Reson Med 75:2332-2340, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
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Lindholm, Anna K.; Sandkam, Ben; Pohl, Kristina; Breden, Felix
2015-01-01
Studies on the evolution of female preference and male color polymorphism frequently focus on single species since traits and preferences are thought to co-evolve. The guppy, Poecilia reticulata, has long been a premier model for such studies because female preferences and orange coloration are well known to covary, especially in upstream/downstream pairs of populations. However, focused single species studies lack the explanatory power of the comparative method, which requires detailed knowledge of multiple species with known evolutionary relationships. Here we describe a red color polymorphism in Poecilia picta, a close relative to guppies. We show that this polymorphism is restricted to males and is maintained in natural populations of mainland South America. Using tests of female preference we show female P. picta are not more attracted to red males, despite preferences for red/orange in closely related species, such as P. reticulata and P. parae. Male color patterns in these closely related species are different from P. picta in that they occur in discrete patches and are frequently Y chromosome-linked. P. reticulata have an almost infinite number of male patterns, while P. parae males occur in discrete morphs. We show the red male polymorphism in P. picta extends continuously throughout the body and is not a Y-linked trait despite the theoretical prediction that sexually-selected characters should often be linked to the heterogametic sex chromosome. The presence/absence of red male coloration of P. picta described here makes this an ideal system for phylogenetic comparisons that could reveal the evolutionary forces maintaining mate choice and color polymorphisms in this speciose group. PMID:26529081
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Torres-Martínez, Aarón; Hernández-Franyutti, Arlette; Uribe, Mari Carmen; Contreras-Sánchez, Wilfrido Miguel
2017-12-01
The structure of the ovary and oogenesis of Poecilia mexicana from an active sulfur spring cave is documented. Poecilia mexicana is the only poeciliid adapted to a subterranean environment with high hydrogen sulfide levels and extreme hypoxic conditions. Twenty females were captured throughout one year at Cueva del Azufre, located in the State of Tabasco in Southern Mexico. Ovaries were processed with histological techniques. P. mexicana has a single, ovoid ovary with ovigerous lamella that project to the ovarian lumen. The ovarian wall presents abundant loose connective tissue, numerous melanomacrophage centers and large blood vessels, possibly associated with hypoxic conditions. The germinal epithelium bordering the ovarian lumen contains somatic and germ cells forming cell nests projecting into the stroma. P. mexicana stores sperm in ovarian folds associated with follicles at different developmental phases. Oogenesis in P. mexicana consisted of the following stages: (i) oogonial proliferation, (ii) chromatin nucleolus, (iii) primary growth, subdivided into: (a) one nucleolus, (b) multiple nucleoli, (c) droplet oils-cortical alveoli steps; (iv) secondary growth, subdivided in: (a) early secondary growth, (b) late secondary growth, and (c) full grown. Follicular atresia was present in all stages of follicular development; it was characterized by oocyte degeneration, where follicle cells hypertrophy and differentiate in phagocytes. The ovary and oogenesis are similar to these seen in other poeciliids, but we found frequent atretic follicles, melanomacrophage centers, reduced fecundity and increased of offspring size. © 2017 Wiley Periodicals, Inc.
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Lee, David; Lee, Joshua; Lee, Imshik
2015-01-01
The locomotor behavior of small fish was characterized under a cell phone-generated radio frequency electromagnetic field (RF EMF). The trajectory of movement of 10 pairs of guppy (Poecilia reticulate) and 15 pairs of Zebrafish (Danio rerio) in a fish tank was recorded and tracked under the presence of a cell phone-generated RF EMF. The measures were based on spatial and temporal distributions. A time-series trajectory was utilized to emphasize the dynamic nature of locomotor behavior. Fish movement was recorded in real-time. Their spatial, velocity, turning angle and sinuosity distribution were analyzed in terms of F(v,x), P[n(x,t)], P(v), F (θ) and F(s), respectively. In addition, potential temperature elevation caused by a cellular phone was also examined. We demonstrated that a cellular phone-induced temperature elevation was not relevant, and that our measurements reflected RF EMF-induced effects on the locomotor behavior of Poecilia reticulata and Danio rerio. Fish locomotion was observed under normal conditions, in the visual presence of a cell phone, after feeding, and under starvation. Fish locomotor behavior was random both in normal conditions and in the presence of an off-signaled cell phone. However, there were significant changes in the locomotion of the fish after feeding under the RF EMF. The locomotion of the fed fish was affected in terms of changes in population and velocity distributions under the presence of the RF EMF emitted by the cell phone. There was, however, no significant difference in angular distribution.
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Martin, B.A.; Saiki, M.K.
2005-01-01
We assessed the relation between abundance of desert pupfish, Cyprinodon macularius, and selected biological and physicochemical variables in natural and manmade habitats within the Salton Sea Basin. Field sampling in a natural tributary, Salt Creek, and three agricultural drains captured eight species including pupfish (1.1% of the total catch), the only native species encountered. According to Bray-Curtis resemblance functions, fish species assemblages differed mostly between Salt Creek and the drains (i.e., the three drains had relatively similar species assemblages). Pupfish numbers and environmental variables varied among sites and sample periods. Canonical correlation showed that pupfish abundance was positively correlated with abundance of western mosquitofish, Gambusia affinis, and negatively correlated with abundance of porthole livebearers, Poeciliopsis gracilis, tilapias (Sarotherodon mossambica and Tilapia zillii), longjaw mudsuckers, Gillichthys mirabilis, and mollies (Poecilia latipinnaandPoecilia mexicana). In addition, pupfish abundance was positively correlated with cover, pH, and salinity, and negatively correlated with sediment factor (a measure of sediment grain size) and dissolved oxygen. Pupfish abundance was generally highest in habitats where water quality extremes (especially high pH and salinity, and low dissolved oxygen) seemingly limited the occurrence of nonnative fishes. This study also documented evidence of predation by mudsuckers on pupfish. These findings support the contention of many resource managers that pupfish populations are adversely influenced by ecological interactions with nonnative fishes. ?? Springer 2005.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Amundsen, C C; McCord, R A
1982-08-01
The vegetation of the central Aleutian Islands, Alaska is maritime tundra (Amundsen, 1977). While maritime tundra is not characterized by the presence of permafrost, the soil temperatures remain low (5 to 7/sup 0/C) year-round (Williams, 1980). The low soil temperature, a high level of soil moisture, and a low level of incident solar radiation are thought to delay the development of the vegetation. Natural revegetation of natural or man made open areas is relatively slow. Disturbed areas from World War II military activity are not completely revegetated after almost 40 years. Because of the windy and wet climate of themore » region, exposed soil is unstable and subject to extensive freeze-thaw action and erosion. Insults to the vegetation, both marine and aeolian, are common. Successful reproduction by seed is uncommon among species of this flora. The primary means of reproduction appears to be by vegetative propagules which are usually fragments of the shoot and rhizome. While the transport of the fragments by wind and water aids in the dispersal of the propagules, the same action often removes these fragments from open areas. This later activity further delays the revegetation of open and disturbed areas. Elymus mollis Trin. is the most successful major native species found to date as it fragments due to wind and water action and transplants easily. Transplanting experiments with sprigs of Elymus mollis Trin. have been conducted on Adak Island, Alaska since 1977. Preliminary results indicate that Elymus mollis may be transplanted for revegetation with a survival rate of at least 90 percent. Experiments were set up in 1979 to determine appropriate planting density, sprig rhizome length, and best time of year for transplanting. Preliminary results for these experiments are reported here.« less
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NASA Astrophysics Data System (ADS)
Ben, D.; Langdon, C. J.
2016-02-01
Pacific dulse (Palmaria mollis) is a candidate for aquaculture production in Oregon due to its high protein content, fast growth rate, and ability to fare in cold water conditions. Current cultivation methods use the F/2 medium to supply nutrients to macroalgae cultures. The F/2 medium is a costly mixture of nitrate, phosphate, trace metals and vitamins. The F/2 medium has been the standard for microalgae cultivation, but research has lacked on the necessity of all or part of this mixture for macroalgae cultivation. This study is designed to contribute to the development of Pacific dulse cultivation by measuring how different fertilizer regimens affect the growth, biochemical composition, and quality of Palmaria mollis (C-3 variety) in hopes to reduce the production cost. I hypothesis that dulse will not require additional nutrients during summer cultivation, due to summer upwelling conditions. Experiments were conducted in a flow-through water system, controlling for flow rate, stocking density, and nutrient supplementation. To test this, two replicates of four nutrient regimes were organized: no supplemental nutrients, all nutrients (standard F/2 medium), nitrate/phosphate only, and nitrate/phosphate with trace metals. Each tank was monitored weekly for color quality, epiphytic growth, specific growth rate, production and a final biochemical analysis. This study has preliminarily concluded that supplemental nutrients have no significant effect on production or biochemical quality, but does have an effect quality of epiphytic growth.
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Palamar, Joseph J; Salomone, Alberto; Vincenti, Marco; Cleland, Charles M
2016-04-01
Ecstasy (MDMA) in the US is commonly adulterated with other drugs, but research has not focused on purity of ecstasy since the phenomenon of "Molly" (ecstasy marketed as pure MDMA) arose in the US. We piloted a rapid electronic survey in 2015 to assess use of novel psychoactive substances (NPS) and other drugs among 679 nightclub/festival-attending young adults (age 18-25) in New York City. A quarter (26.1%) of the sample provided a hair sample to be analyzed for the presence of select synthetic cathinones ("bath salts") and some other NPS. Samples were analyzed using fully validated UHPLC-MS/MS methods. To examine consistency of self-report, analyses focused on the 48 participants with an analyzable hair sample who reported lifetime ecstasy/MDMA/Molly use. Half (50.0%) of the hair samples contained MDMA, 47.9% contained butylone, and 10.4% contained methylone. Of those who reported no lifetime use of "bath salts", stimulant NPS, or unknown pills or powders, about four out of ten (41.2%) tested positive for butylone, methylone, alpha-PVP, 5/6-APB, or 4-FA. Racial minorities were more likely to test positive for butylone or test positive for NPS after reporting no lifetime use. Frequent nightclub/festival attendance was the strongest predictor of testing positive for MDMA, butylone, or methylone. Results suggest that many ecstasy-using nightclub/festival attendees may be unintentionally using "bath salts" or other NPS. Prevention and harm reduction education is needed for this population and "drug checking" (e.g., pill testing) may be beneficial for those rejecting abstinence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
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Extreme habitats as refuge from parasite infections? Evidence from an extremophile fish
NASA Astrophysics Data System (ADS)
Tobler, Michael; Schlupp, Ingo; García de León, Francisco J.; Glaubrecht, Matthias; Plath, Martin
2007-05-01
Living in extreme habitats typically requires costly adaptations of any organism tolerating these conditions, but very little is known about potential benefits that trade off these costs. We suggest that extreme habitats may function as refuge from parasite infections, since parasites can become locally extinct either directly, through selection by an extreme environmental parameter on free-living parasite stages, or indirectly, through selection on other host species involved in its life cycle. We tested this hypothesis in a small freshwater fish, the Atlantic molly ( Poecilia mexicana) that inhabits normal freshwaters as well as extreme habitats containing high concentrations of toxic hydrogen sulfide. Populations from such extreme habitats are significantly less parasitized by the trematode Uvulifer sp. than a population from a non-sulfidic habitat. We suggest that reduced parasite prevalence may be a benefit of living in sulfidic habitats.
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Stable Inheritance of Host Species-Derived Microchromosomes in the Gynogenetic Fish Poecilia formosa
Nanda, Indrajit; Schlupp, Ingo; Lamatsch, Dunja K.; Lampert, Kathrin P.; Schmid, Michael; Schartl, Manfred
2007-01-01
B chromosomes are additional, usually unstable constituents of the genome of many organisms. Their origin, however, is often unclear and their evolutionary relevance is not well understood. They may range from being deleterious to neutral or even beneficial. We have followed the genetic fate of B chromosomes in the asexual, all-female fish Poecilia formosa over eight generations. In this species, B chromosomes come in the form of one to three tiny microchromosomes derived from males of the host species that serve as sperm donors for this gynogenetic species. All microchromosomes have centromeric heterochromatin but usually only one has a telomere. Such microchromosomes are stably inherited, while the telomereless are prone to be lost in both the soma and germline. In some cases the stable microchromosome carries a functional gene lending support to the hypothesis that the B chromosomes in P. formosa could increase the genetic diversity of the clonal lineage in this ameiotic organism and to some degree counteract the genomic decay that is supposed to be connected with the lack of recombination. PMID:17720916
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Kavitha, P; Ramesh, R; Subramanian, P
2012-05-01
Tribulus terrestris is a traditionally known non-toxic aphrodisiac herb for maleness. It was experimented recently to understand the effect and mechanism on mono sex production in Poecilia latipinna. It would help to develop a new eco-friendly way to masculinize P. latipinna, since males have higher commercial value than females. The different concentration (100, 150, 200, 250 and 300 mg/L) of T. terrestris extract and a control were tested for their effect on sex transformation/reversal in P. latipinna by immersing the newly born young ones in the respective concentrations for 2 mo. The obtained results indicate that a dose dependant masculinization is obtained due to T. terrestris administration, which improved the male proportion. Histological results revealed that the testes of fish treated with T. terrestris extract contained all stages of spermatogenesis, clearly demonstrating that the administration of T. terrestris extract to P. latipinna stimulated spermatogenesis. Thus, it is discernible that 0-d-old hatchlings of P. latipinna exposed to T. terrestris extract orient/reverse their sex more towards maleness besides yielding better growth and spermatogenesis which is a mandate for fancy fish industry.
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Malaria Disease Mapping in Malaysia based on Besag-York-Mollie (BYM) Model
NASA Astrophysics Data System (ADS)
Azah Samat, Nor; Mey, Liew Wan
2017-09-01
Disease mapping is the visual representation of the geographical distribution which give an overview info about the incidence of disease within a population through spatial epidemiology data. Based on the result of map, it helps in monitoring and planning resource needs at all levels of health care and designing appropriate interventions, tailored towards areas that deserve closer scrutiny or communities that lead to further investigations to identify important risk factors. Therefore, the choice of statistical model used for relative risk estimation is important because production of disease risk map relies on the model used. This paper proposes Besag-York-Mollie (BYM) model to estimate the relative risk for Malaria in Malaysia. The analysis involved using the number of Malaria cases that obtained from the Ministry of Health Malaysia. The outcomes of analysis are displayed through graph and map, including Malaria disease risk map that constructed according to the estimation of relative risk. The distribution of high and low risk areas of Malaria disease occurrences for all states in Malaysia can be identified in the risk map.
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Palamar, Joseph J; Acosta, Patricia; Ompad, Danielle C; Cleland, Charles M
2017-01-02
Ecstasy (MDMA) use has regained popularity in the United States, particularly in the form of "Molly," which is often marketed as pure MDMA. Surveys have generally not included "Molly" in the definition of ecstasy, so rates of use may be underestimated. As popularity of ecstasy increases, research is needed to examine use among those at highest risk for use-nightlife attendees. We surveyed 679 young adults (age 18-25) entering nightclubs and festivals holding electronic dance music (EDM) parties in New York City in 2015. A variation of time-space sampling was utilized. We examined prevalence and correlates of self-reported lifetime ecstasy use. Self-reported lifetime ecstasy use was common (42.8%, 95% CI: 32.8, 52.7). Use was most common among older participants, frequent party attendees, and those reporting higher levels of exposure to users. Those surveyed outside of festivals were less likely to report use compared to those surveyed outside of nightclubs (AOR = 0.37, p = .015). Over a third of ecstasy users (36.8%)reported use in pill, powder, and crystal form. Ecstasy users were also more likely to report use of other drugs, including novel psychoactive substances (e.g., 2C series drugs, synthetic cathinones ["bath salts"]). Half (50.4%) reported suspecting (21.9%) or finding out (28.5%) that their ecstasy had ever contained a drug other than MDMA. A large percentage of nightlife attendees in NYC report lifetime ecstasy use. Findings should inform prevention and harm reduction programming. Further research is needed as ecstasy continues to change (e.g., in form, purity, and name).
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Reinert, Robert E.
1972-01-01
Scenedesmus obliquus, Daphnia magna, and Poecilia reticulata accumulated dieldrin directly from water; average concentration factors (concentration in organism, dry weight, divided by concentration in water) were 1282 for the alga, 13,954 for D. magna, and 49,307 (estimated) for the guppy. The amount accumulated by each species at equilibrium (after about 1.5, 3-4, and 18 days, respectively) was directly proportional to the concentration of dieldrin in the water. Daphnia magna and guppies accumulated more dieldrin from water than from food that had been exposed to similar concentrations in water. When guppies were fed equal daily rations of D. magna containing different concentrations of insecticide, the amounts of dieldrin accumulated by the fish were directly proportional to the concentration in D. magna; when two lots of guppies were fed different quantities of D. magna (10 and 20 organisms per day) containing identical concentrations of dieldrin, however, the amounts accumulated did not differ substantially.
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Tavakol, Sareh; Halajian, Ali; Smit, Willem J; Hoffman, Andre; Luus-Powell, Wilmien J
2017-12-01
Introduced alien fish species and their associated parasites may result in a serious threat to indigenous biodiversity. Furthermore, this may have negative impacts on cultured fish as well as on native parasitic fauna. In the present study, the invasive Asian nematode, Camallanus cotti Fujita, 1927 (Nematoda: Camallanidae), is reported from the guppy (Poecilia reticulata) for the first time in Africa. This parasite is assumed to be introduced into Africa along with the introduction of exotic poeciliid fishes, which are known to be the most common hosts of C. cotti in ornamental fish industry worldwide.The presence of this parasite in both aquarium-cultured fish as well as fish from natural waterbodies is evidence of the introduction of the alien organisms due to insufficient prophylactic veterinary control during transfer of non-native hosts between countries and the spread of them by the anthropogenic introduction to natural systems.
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Friedlander, Alan M.; DeMartini, Edward E.; Schuhbauer, Anna; Schemmel, Eva; Salinas de Léon, Pelayo
2015-01-01
The Galapagos Sailfin grouper, Mycteroperca olfax, locally known as bacalao and listed as vulnerable by the IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of the Galapagos fishery for this species. Previous estimates of longevity and size at maturity for bacalao are inconsistent with estimates for congeners, which brings into question the accuracy of prior estimates. We set out to assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 21 years old, which is 2–3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k = 0.11, L∞ = 110 cm TL, and to = − 1.7 years) show bacalao to grow much slower and attain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 65.3 cm TL, corresponding to a mean age of 6.5 years. We found that sex ratios were extremely female biased (0.009 M:1F), with a large majority of the individuals in our experimental catch being immature (79%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have important implications for the fishery of this valuable species and provide the impetus for a long-overdue species management plan to ensure its long-term sustainability. PMID:26401463
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Usseglio, Paolo; Friedlander, Alan M; DeMartini, Edward E; Schuhbauer, Anna; Schemmel, Eva; Salinas de Léon, Pelayo
2015-01-01
The Galapagos Sailfin grouper, Mycteroperca olfax, locally known as bacalao and listed as vulnerable by the IUCN, is culturally, economically, and ecologically important to the Galapagos archipelago and its people. It is regionally endemic to the Eastern Tropical Pacific, and, while an important fishery resource that has shown substantial declines in recent years, to date no effective management regulations are in place to ensure the sustainability of the Galapagos fishery for this species. Previous estimates of longevity and size at maturity for bacalao are inconsistent with estimates for congeners, which brings into question the accuracy of prior estimates. We set out to assess the age, growth, and reproductive biology of bacalao in order to provide more accurate life history information to inform more effective fisheries management for this species. The oldest fish in our sample was 21 years old, which is 2-3 times greater than previously reported estimates of longevity. Parameter estimates for the von Bertalanffy growth function (k = 0.11, L ∞ = 110 cm TL, and to = - 1.7 years) show bacalao to grow much slower and attain substantially larger asymptotic maximum length than previous studies. Mean size at maturity (as female) was estimated at 65.3 cm TL, corresponding to a mean age of 6.5 years. We found that sex ratios were extremely female biased (0.009 M:1F), with a large majority of the individuals in our experimental catch being immature (79%). Our results show that bacalao grow slower, live longer, and mature at a much larger size and greater age than previously thought, with very few mature males in the population. These findings have important implications for the fishery of this valuable species and provide the impetus for a long-overdue species management plan to ensure its long-term sustainability.
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Sexual characteristics of male guppies Poecilia reticulata serve as effect biomarkers of estrogens
NASA Astrophysics Data System (ADS)
Tian, Hua; Li, Yun; Wang, Wei; Zhao, Fei; Gao, Su; Ru, Shaoguo
2017-10-01
Guppies (Poecilia reticulata) are considered a candidate model species for the identification and testing of endocrine-disrupting chemicals. Male guppies may be used to address the challenge of making potential linkages between alterations of biomarkers, both at the cellular and organ level, and adverse outcomes. In the present study, a predictive relationship between sex characteristics and reproductive output was observed in male guppies that underwent a long-term toxicity test with 0.5 μg/L 17β-estradiol administered during the juvenile period. Radioimmunoassay and western blot analyses demonstrated that 17β-estradiol exposure caused a significant increase in testicular 17β-estradiol levels as well as the induction of exposure biomarkers, namely hepatic vitellogenin. Exposure to 17β-estradiol also caused a significant decrease in testosterone levels, which consequently reduced the gonadosomatic index, sperm counts, and the coloration index. These changes of male sexual characteristics further translated into adverse influences on reproduction, as measured by a decrease in off spring production and survival rate. Our results suggest that the above-mentioned sexual characteristics of male guppies may be considered potential in vivo biomarkers of estrogen effects on reproduction.
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De Barros, Thais C; Pedersoli, Giseli D; Paulino, Juliana V; Teixeira, Simone P
2017-02-01
Pentaclethra and Dimorphandra (Leguminosae) have long been considered a possible enigmatic link between caesalpinioids and mimosoids because they both have an imbricate calyx and heteromorphic androecium, floral features that are rare among mimosoids but common among caesalpinioids. This study compared the developing flowers of Dimorphandra mollis and Pentaclethra macroloba to determine whether the shared floral conditions also have the same ontogenetic origin. Buds of different sizes and flowers were processed for surface (scanning electron microscopy) and histological (light microscopy) examination. The floral meristem initiates five sepal primordia in a modified helical order in both species. The median sagittal sepal is adaxial. The overlap of the sepals during elongation culminates with the formation of the imbricate calyx. Heteromorphic androecia arise in the intermediate stages of development. In P. macroloba , the fertile pollen-bearing stamens are antesepalous, robust and short, and the anthers carry a robust apical gland; the staminodes are long and white with a vestigial apical gland. In contrast, in D. mollis the fertile pollen-bearing stamens are antepetalous without glands and as long as the staminodes. The staminodes are thinner with an expanded apical region. The imbricate calyx and the heteromorphic androecium in the studied species originated via distinct pathways, favoring the hypothesis of homoplasy of these conditions. The pathways observed in P. macroloba are more similar to those observed in caesalpinioids than to those observed in mimosoids, indicating that although the floral development differs between the species studied, it supports the basal placement of Pentaclethra among mimosoids. © 2017 Botanical Society of America.
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Reduced opsin gene expression in a cave-dwelling fish
Tobler, Michael; Coleman, Seth W.; Perkins, Brian D.; Rosenthal, Gil G.
2010-01-01
Regressive evolution of structures associated with vision in cave-dwelling organisms is the focus of intense research. Most work has focused on differences between extreme visual phenotypes: sighted, surface animals and their completely blind, cave-dwelling counterparts. We suggest that troglodytic systems, comprising multiple populations that vary along a gradient of visual function, may prove critical in understanding the mechanisms underlying initial regression in visual pathways. Gene expression assays of natural and laboratory-reared populations of the Atlantic molly (Poecilia mexicana) revealed reduced opsin expression in cave-dwelling populations compared with surface-dwelling conspecifics. Our results suggest that the reduction in opsin expression in cave-dwelling populations is not phenotypically plastic but reflects a hardwired system not rescued by exposure to light during retinal ontogeny. Changes in opsin gene expression may consequently represent a first evolutionary step in the regression of eyes in cave organisms. PMID:19740890
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NASA Astrophysics Data System (ADS)
Slater, Matthew J.; Jeffs, Andrew G.
2010-10-01
Despite the economic importance of many deposit-feeding sea cucumbers, the ecology of their juveniles is poorly understood and factors influencing juvenile habitat selection remain largely unexplained. We investigated the importance of the characteristics of the available sediment in determining the highly localised distribution of juveniles of the deposit-feeding Australasian sea cucumber Australostichopus mollis. Wild-caught juveniles were displaced to non-juvenile habitats with surface sediments characterised by lower total organic content (TOM) and nitrogen content, higher chlorophyll- a content and coarser grain size profiles compared to juvenile sites. The growth of displaced individual animals was monitored over 9 months and compared to control animals caged in the juvenile habitats. Displaced juvenile sea cucumbers had high survival rates that did not differ significantly from juvenile habitats. Displaced juveniles exhibited significantly higher specific growth rate (SGR) than those at juvenile sites ( p < 0.001), although the growth of individuals was highly variable within individual cages and among sites. The lower TOM and nitrogen content, and coarser grain size profiles at non-juvenile sites did not result in reductions in juvenile survival or growth. Higher microphytobenthic activity may have resulted in the higher growth rates observed at shallow non-juvenile sites. The SGR of juveniles over the first 6 months of the experiment ranged between 0.45% d - 1 and 0.74% d - 1 for all sites. This was followed by marked growth limitation between 6 and 9 months either as a result of increasing juvenile biomass in cages or seasonal growth limitation. A subsequent reduction in juvenile density resulted in markedly increased growth over the following 3 month period. Juvenile A. mollis show an ability to exploit a variety of benthic sediment food sources, indicating that their highly localised distribution is not due to differences in the food quality of
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Diaz Pauli, B; Wiech, M; Heino, M; Utne-Palm, A C
2015-03-01
This study assessed whether fishing gear was selective on behavioural traits, such as boldness and activity, and how this was related with a productivity trait, growth. Female guppies Poecilia reticulata were screened for their behaviour on the shy-bold axis and activity, and then tested whether they were captured differently by passive and active fishing gear, here represented by a trap and a trawl. Both gears were selective on boldness; bold individuals were caught faster by the trap, but escaped the trawl more often. Boldness and gear vulnerability showed weak correlations with activity and growth. The results draw attention to the importance of the behavioural dimension of fishing: selective fishing on behavioural traits will change the trait composition of the population, and might eventually affect resilience and fishery productivity. © 2015 The Fisheries Society of the British Isles.
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Toledo-Ibarra, G A; Rodríguez-Sánchez, E J; Ventura-Ramón, H G; Díaz-Resendiz, K J G; Girón-Pérez, M I
2018-02-01
Spinosad and temephos are two of the most used pesticides in Mexico for the control of vector causing disease such as dengue, chikungunya and Zika. The aim of this study was to compare the neurotoxic effects of these two pesticides using guppy fish (Poecilia reticulata) as a model organism. Guppies were exposed for 7 and 21 days to technical grade temephos and spinosad at 1.0 and 0.07 g/L, respectively, (10 and 0.5 mg/L of active substance; concentrations recommended by the Ministery of Health of the State (Secretaría de Salud de Nayarit (SSN) Mexico)). Subsequently, acetylcholinesterase activity (AChE) and acetylcholine concentrations (ACh) in muscle tissue were determined. Temephos exposure decreased AChE activity and increased ACh concentration, whereas exposure to spinosad only increased ACh concentration. Though cholinergic alterations were more severe in fish exposed to temephos, both pesticides were equally lethal during the first seven days after exposure. Nonetheless, temephos was more lethal after 21 days.
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Dreyer, Christine; Hoffmann, Margarete; Lanz, Christa; Willing, Eva-Maria; Riester, Markus; Warthmann, Norman; Sprecher, Andrea; Tripathi, Namita; Henz, Stefan R; Weigel, Detlef
2007-01-01
Background The guppy, Poecilia reticulata, is a well-known model organism for studying inheritance and variation of male ornamental traits as well as adaptation to different river habitats. However, genomic resources for studying this important model were not previously widely available. Results With the aim of generating molecular markers for genetic mapping of the guppy, cDNA libraries were constructed from embryos and different adult organs to generate expressed sequence tags (ESTs). About 18,000 ESTs were annotated according to BLASTN and BLASTX results and the sequence information from the 3' UTRs was exploited to generate PCR primers for re-sequencing of genomic DNA from different wild type strains. By comparison of EST-linked genomic sequences from at least four different ecotypes, about 1,700 polymorphisms were identified, representing about 400 distinct genes. Two interconnected MySQL databases were built to organize the ESTs and markers, respectively. A robust phylogeny of the guppy was reconstructed, based on 10 different nuclear genes. Conclusion Our EST and marker databases provide useful tools for genetic mapping and phylogenetic studies of the guppy. PMID:17686157
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Riesch, R; Plath, M; Schlupp, I
2011-03-01
Chronic environmental stress is known to induce evolutionary change. Here, we assessed male life-history trait divergence in the neotropical fish Poecilia mexicana from a system that has been described to undergo incipient ecological speciation in adjacent, but reproductively isolated toxic/nontoxic and surface/cave habitats. Examining both field-caught and common garden-reared specimens, we investigated the extent of differentiation and plasticity of life-history strategies employed by male P. mexicana. We found strong site-specific life-history divergence in traits such as fat content, standard length and gonadosomatic index. The majority of site-specific life-history differences were also expressed under common garden-rearing conditions. We propose that apparent conservatism of male life histories is the result of other (genetically based) changes in physiology and behaviour between populations. Together with the results from previous studies, this is strong evidence for local adaptation as a result of ecologically based divergent selection. © 2010 The Authors. Journal of Evolutionary Biology © 2010 European Society For Evolutionary Biology.
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Arbuatti, Alessio; Della Salda, Leonardo; Romanucci, Mariarita
2013-03-01
To describe the occurrence of various spinal deformations in a captive-bred wild line of Poecilia wingei (P. wingei). Fish belonging to a wild line of P. wingei caught from Laguna de Los Patos, Venezuela, were bred in an aquarium home-breeding system during a period of three years (2006-2009). The spinal curvature was observed to study spinal deformities in P. wingei. Out of a total of 600 fish, 22 showed different types of deformities (scoliosis, lordosis, kyphosis), with a higher incidence in females. Growth, swimming and breeding of deformed fish were generally normal. Possible causes for spinal curvature in fish are discussed on the basis of the current literature. While it is not possible to determine the exact cause(s) of spinal deformities observed in the present study, traumatic injuries, nutritional imbalances, genetic defects or a combination of these factors can be supposed to be involved in the pathogenesis of such lesions.
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Park, Keehae; Heo, Gang-Joon
2009-03-01
Chemicals are used for treatment of aquatic diseases, but there is little data available about copper sulfate in small ornamental fish. The aim of the present study was to determine the TLm(24h) and evaluate the toxicity of copper sulfate in the guppy (Poecilia reticulata). The fish were subjected to an acute toxicity test for 24 hr, and the results showed a TLm(24h) value of 1.17 ppm. Severe hyperplasia and exfoliation of the epithelial cells of gill lamellae and obstruction of the internal cavities of renal tubules with necrotized renal epithelial cells sloughed from the basement membrane were observed. However, no significant changes, except for mild curling of gill lamellae, were found in a subacute toxicity test in which fish were exposed to 1/10 of the TLm(24h) value for 1 week. Therefore, use of less than 0.12 ppm of copper sulfate may be recommended as a therapeutic level.
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Riesch, Rüdiger; Plath, Martin; Schlupp, Ingo
2010-05-01
Life-history traits are very sensitive to extreme environmental conditions, because resources that need to be invested in somatic maintenance cannot be invested in reproduction. Here we examined female life-history traits in the Mexican livebearing fish Poecilia mexicana from a variety of benign surface habitats, a creek with naturally occurring toxic hydrogen sulfide (H2S), a sulfidic cave, and a non-sulfidic cave. Previous studies revealed pronounced genetic and morphological divergence over very small geographic scales in this system despite the absence of physical barriers, suggesting that local adaptation to different combinations of two selection factors, toxicity (H2S) and darkness, is accompanied by very low rates of gene flow. Hence, we investigated life-history divergence between these populations in response to the selective pressures of darkness and/or toxicity. Our main results show that toxicity and darkness both select for (or impose constraints on) the same female trait dynamics: reduced fecundity and increased offspring size. Since reduced fecundity in the sulfur cave population was previously shown to be heritable, we discuss how divergent life-history evolution may promote further ecological divergence: for example, reduced fecundity and increased offspring autonomy are clearly beneficial in extreme environments, but fish with these traits are outcompeted in benign habitats.
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Smallbone, Willow; van Oosterhout, Cock; Cable, Jo
2016-08-01
Inbreeding can threaten population persistence by reducing disease resistance through the accelerated loss of gene diversity (i.e. heterozygosity). Such inbreeding depression can affect many different fitness-related traits, including survival, reproductive success, and parasite susceptibility. Empirically quantifying the effects of inbreeding on parasite resistance is therefore important for ex-situ conservation of vertebrates. The present study evaluates the disease susceptibility of individuals bred under three different breeding regimes (inbred, crossed with full siblings; control, randomly crossed mating; and fully outbred). Specifically, we examined the relationship between inbreeding coefficient (F-coefficient) and susceptibility to Gyrodactylus turnbulli infection in a live bearing vertebrate, the guppy Poecilia reticulata. Host-breeding regime significantly affected the trajectories of parasite population growth on individual fish. Inbred fish showed significantly higher mean parasite intensity than fish from the control and outbred breeding regimes, and in addition, inbred fish were slower in purging their gyrodactylid infections. We discuss the role of inbreeding on the various arms of the immune system, and argue that the increased disease susceptibility of inbred individuals could contribute to the extinction vortex. This is one of the first studies to quantify the effects of inbreeding and breeding regime on disease susceptibility in a captive bred vertebrate of wild origin, and it highlights the risks faced by small (captive-bred) populations when exposed to their native parasites. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
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Escarrone, Ana Laura Venquiaruti; Caldas, Sergiane Souza; Primel, Ednei Gilberto; Martins, Samantha Eslava; Nery, Luiz Eduardo Maia
2016-08-01
The agent triclosan has been extensively used in different personal care products as a broad-spectrum antimicrobial and preservative agent. Due to its continuous release into the environment, including discharge via wastewater treatment plants, triclosan has been widely detected in aquatic environments. There is growing interest in improving the knowledge about the environmental fate of triclosan due to its possible bioaccumulation and the toxicity it may pose to organisms, such as fish and other non-target species. To investigate the distribution and bioconcentration of triclosan in fish, Poecilia vivipara was exposed to 0.2mgL(-1). Contents of triclosan in whole fish, brain, gonads, liver, muscle and gills were quantified by LC-MS/MS. When lipid normalised concentration was used, the liver exhibited the highest concentration followed by the gills, gonads, brain and muscle tissues. Bioconcentration was increased with time reaching a steady-state around 7-14days for most all tissues. After 24h depuration, triclosan concentrations declined >80% in all tissues except liver, in which triclosan takes longer to be depurated. These results not only clearly indicate that triclosan accumulated in P. vivipara, with tissue-specific bioconcentration factors (BCF) that ranged from 40.2 to 1025.4, but also show that the elimination of triclosan after transferring the fish to triclosan-free freshwater is rapid in all tissues. Copyright © 2016 Elsevier B.V. All rights reserved.
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Lindholm, Anna K; Hunt, John; Brooks, Robert
2006-12-22
Maternal effects are an important source of adaptive variation, but little is known about how they vary throughout ontogeny. We estimate the contribution of maternal effects, sire genetic and environmental variation to offspring body size from birth until 1 year of age in the live-bearing fish Poecilia parae. In both the sexes, maternal effects on body size were initially high in juveniles, and then declined to zero at sexual maturity. In sons, this was accompanied by a sharp rise in sire genetic variance, consistent with the expression of Y-linked loci affecting male size. In daughters, all variance components decreased with time, consistent with compensatory growth. There were significant negative among-dam correlations between early body size and the timing of sexual maturity in both sons and daughters. However, there was no relationship between early life maternal effects and adult longevity, suggesting that maternal effects, although important early in life, may not always influence late life-history traits.
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Berbel-Filho, Waldir Miron; Barros-Neto, Luciano Freitas; Dias, Ricardo Marques; Mendes, Liana Figueiredo; Figueiredo, Carlos Augusto Assumpção; Torres, Rodrigo Augusto; Lima, Sergio Maia Queiroz
2018-01-01
Poecilia vivipara , a small euryhaline guppy is reported at the Maceió River micro-basin in the Fernando de Noronha oceanic archipelago, northeast Brazil. However, the origin (human-mediated or natural dispersal) of this insular population is still controversial. The present study investigates how this population is phylogenetically related to the surrounding continental populations using the cytochrome oxidase I mitochondrial gene from eleven river basins in South America. Our phylogenetic reconstruction showed a clear geographical distribution arrangement of P. vivipara lineages. The Fernando de Noronha haplotype fell within the 'north' clade, closely related to a shared haplotype between the Paraíba do Norte and Potengi basins; the geographically closest continental drainages. Our phylogenetic reconstruction also showed highly divergent lineages, suggesting that P. vivipara may represent a species complex along its wide distribution. Regarding to the insular population, P. vivipara may have been intentionally introduced to the archipelago for the purpose of mosquito larvae control during the occupation of a U.S. military base following World War II. However, given the euryhaline capacity of P. vivipara , a potential scenario of natural (passive or active) dispersal cannot be ruled out.
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Berbel-Filho, Waldir Miron; Barros-Neto, Luciano Freitas; Dias, Ricardo Marques; Mendes, Liana Figueiredo; Figueiredo, Carlos Augusto Assumpção; Torres, Rodrigo Augusto; Lima, Sergio Maia Queiroz
2018-01-01
Abstract Poecilia vivipara, a small euryhaline guppy is reported at the Maceió River micro-basin in the Fernando de Noronha oceanic archipelago, northeast Brazil. However, the origin (human-mediated or natural dispersal) of this insular population is still controversial. The present study investigates how this population is phylogenetically related to the surrounding continental populations using the cytochrome oxidase I mitochondrial gene from eleven river basins in South America. Our phylogenetic reconstruction showed a clear geographical distribution arrangement of P. vivipara lineages. The Fernando de Noronha haplotype fell within the 'north' clade, closely related to a shared haplotype between the Paraíba do Norte and Potengi basins; the geographically closest continental drainages. Our phylogenetic reconstruction also showed highly divergent lineages, suggesting that P. vivipara may represent a species complex along its wide distribution. Regarding to the insular population, P. vivipara may have been intentionally introduced to the archipelago for the purpose of mosquito larvae control during the occupation of a U.S. military base following World War II. However, given the euryhaline capacity of P. vivipara, a potential scenario of natural (passive or active) dispersal cannot be ruled out. PMID:29674897
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Tobler, Michael; Dewitt, Thomas J; Schlupp, Ingo; García de León, Francisco J; Herrmann, Roger; Feulner, Philine G D; Tiedemann, Ralph; Plath, Martin
2008-10-01
Divergent natural selection drives evolutionary diversification. It creates phenotypic diversity by favoring developmental plasticity within populations or genetic differentiation and local adaptation among populations. We investigated phenotypic and genetic divergence in the livebearing fish Poecilia mexicana along two abiotic environmental gradients. These fish typically inhabit nonsulfidic surface rivers, but also colonized sulfidic and cave habitats. We assessed phenotypic variation among a factorial combination of habitat types using geometric and traditional morphometrics, and genetic divergence using quantitative and molecular genetic analyses. Fish in caves (sulfidic or not) exhibited reduced eyes and slender bodies. Fish from sulfidic habitats (surface or cave) exhibited larger heads and longer gill filaments. Common-garden rearing suggested that these morphological differences are partly heritable. Population genetic analyses using microsatellites as well as cytochrome b gene sequences indicate high population differentiation over small spatial scale and very low rates of gene flow, especially among different habitat types. This suggests that divergent environmental conditions constitute barriers to gene flow. Strong molecular divergence over short distances as well as phenotypic and quantitative genetic divergence across habitats in directions classic to fish ecomorphology suggest that divergent selection is structuring phenotypic variation in this system.
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Martínez, Celestino; Chavarría, Carmen; Sharpe, Diana M. T.; De León, Luis Fernando
2016-01-01
Colour polymorphism is a recurrent feature of natural populations, and its maintenance has been studied in a range of taxa in their native ranges. However, less is known about whether (and how) colour polymorphism is maintained when populations are removed from their native environments, as in the case of introduced species. We here address this issue by analyzing variation in colour patterns in recently-discovered introduced populations of the guppy (Poecilia reticulata) in Panama. Specifically, we use classic colour analysis to estimate variation in the number and the relative area of different colour spots across low predation sites in the introduced Panamanian range of the species. We then compare this variation to that found in the native range of the species under low- and high predation regimes. We found aspects of the colour pattern that were both consistent and inconsistent with the classical paradigm of colour evolution in guppies. On one hand, the same colours that dominated in native populations (orange, iridescent and black) were also the most dominant in the introduced populations in Panama. On the other, there were no clear differences between either introduced-low and native low- and high predation populations. Our results are therefore only partially consistent with the traditional role of female preference in the absence of predators, and suggest that additional factors could influence colour patterns when populations are removed from their native environments. Future research on the interaction between female preference and environmental variability (e.g. multifarious selection), could help understand adaptive variation in this widely-introduced species, and the contexts under which variation in adaptive traits parallels (or not) variation in the native range. PMID:26863538
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Martínez, Celestino; Chavarría, Carmen; Sharpe, Diana M T; De León, Luis Fernando
2016-01-01
Colour polymorphism is a recurrent feature of natural populations, and its maintenance has been studied in a range of taxa in their native ranges. However, less is known about whether (and how) colour polymorphism is maintained when populations are removed from their native environments, as in the case of introduced species. We here address this issue by analyzing variation in colour patterns in recently-discovered introduced populations of the guppy (Poecilia reticulata) in Panama. Specifically, we use classic colour analysis to estimate variation in the number and the relative area of different colour spots across low predation sites in the introduced Panamanian range of the species. We then compare this variation to that found in the native range of the species under low- and high predation regimes. We found aspects of the colour pattern that were both consistent and inconsistent with the classical paradigm of colour evolution in guppies. On one hand, the same colours that dominated in native populations (orange, iridescent and black) were also the most dominant in the introduced populations in Panama. On the other, there were no clear differences between either introduced-low and native low- and high predation populations. Our results are therefore only partially consistent with the traditional role of female preference in the absence of predators, and suggest that additional factors could influence colour patterns when populations are removed from their native environments. Future research on the interaction between female preference and environmental variability (e.g. multifarious selection), could help understand adaptive variation in this widely-introduced species, and the contexts under which variation in adaptive traits parallels (or not) variation in the native range.
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Schelkle, Bettina; Snellgrove, Donna; Cable, Joanne
2013-11-15
Traditional compounds used to treat fish diseases in aquaculture and the ornamental fish industry (such as formalin and malachite green) can be more toxic to the hosts than their parasites. With the reviviscence in the use of herbal products, various botanicals have been heralded as cures for particular pathogens, but the efficacy of these compounds for parasitic worms is questionable. Here, we tested a range of garlic (Allium sativum) products against a major aquarium pathogen, Gyrodactylus turnbulli, infecting the guppy (Poecilia reticulata). All garlic products significantly reduced parasite mean survival time in vitro, from 13 h to <1 h. In fully randomised trials, the number of parasites was also significantly reduced on infected fish exposed to garlic from different sources. Two garlic treatments (minced and granule forms) reduced worm burdens by 66% and 75% after three doses, whereas Chinese freeze-dried garlic and allyl disulphide were 95% effective after a single application. In fact, Chinese freeze dried garlic was equally effective as Levamisole, a licensed livestock dewormer that is highly effective against G. turnbulli but not routinely prescribed for use in fish; hence, garlic may be a potential alternative treatment for gyrodactylosis. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.
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Hockley, F A; Wilson, C A M E; Graham, N; Cable, J
2014-01-01
Group living in fish can provide benefits of protection from predators and some parasites, more efficient foraging for food, increased mating opportunities and enhanced energetic benefit when swimming. For riverine species, shoaling behaviour can be influenced by various environmental stressors, yet little is known how flow rate might influence the shoaling of diseased fish shoals. In view of the increasingly unpredictable flow rates in streams and rivers, this study aimed to assess the combined effect of flow condition and parasitism on the shoaling behaviour of a model fish species. Shoal size, shoal cohesion and time spent shoaling of female guppies Poecilia reticulata were compared when infected with the directly transmitted ectoparasite Gyrodactylus turnbulli under flow and static conditions. Flow condition was an important factor in influencing shoaling behaviour of guppies with the fish forming larger shoals in the absence of flow. When a shoal member was infected with G. turnbulli , shoal cohesion was reduced, but the magnitude of this effect was dependent on flow condition. In both flow and static conditions, bigger fish formed larger shoals than smaller counterparts. Future changes to stream hydrology with more frequent flooding and drought events will affect the shoaling tendency of fish. During high-flow events, diseased fish may not be able to keep up with shoal mates and therefore have a higher risk of predation. Additionally, these findings may be important for aquaria and farmed species where an increase in flow rate may reduce aggregation in fish.
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Saaristo, Minna; McLennan, Alisha; Johnstone, Christopher P; Clarke, Bradley O; Wong, Bob B M
2017-02-01
Chemical pollution from pharmaceuticals is increasingly recognised as a major threat to aquatic communities. One compound of great concern is fluoxetine, which is one of the most widely prescribed psychoactive drugs in the world and frequently detected in the environment. The aim of this study was to investigate the effects of 28-d fluoxetine exposure at two environmentally relevant levels (measured concentrations: 4ng/L and 16ng/L) on anti-predator behaviour in wild guppies (Poecilia reticulata). This was achieved by subjecting fluoxetine-exposed and unexposed guppies to a simulated bird strike and recording their subsequent behavioural responses. We found that exposure to fluoxetine affected the anti-predator behaviour of guppies, with exposed fish remaining stationary for longer (i.e. 'freezing' behaviour) after the simulated strike and also spending more time under plant cover. By contrast, control fish were significantly more active and explored the tank more, as indicated by the distance covered per minute over the period fish spent swimming. Furthermore, behavioural shifts were sex-dependent, with evidence of a non-monotonic dose-response among the fluoxetine-exposed fish. This is one of the first studies to show that exposure to environmentally relevant concentrations of fluoxetine can alter the anti-predator behaviour of adult fish. In addition to the obvious repercussions for survival, impaired anti-predator behaviour can have direct impacts on fitness and influence the overall population dynamics of species. Copyright © 2016 Elsevier B.V. All rights reserved.
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Antolin, Michael F.; Van Horne, Beatrice; Berger, Michael D.
2001-01-01
Piute ground squirrels (Spermophilus mollis) are distributed continuously in habitat dominated by native shrubs and perennial grasses in the Snake River Birds of Prey National Conservation Area in Idaho, U.S.A. This habitat is being fragmented and replaced by exotic annual plants, changing it to a wildfire-dominated system that provides poor habitat for ground squirrels. To assess potential effects of this fragmentation on ground squirrel populations, we combined an estimate of effective population size (Ne) based upon a demographic study with a population genetic analysis. The study area included three subpopulations separated from each other by 813 km. The ratio of effective population size to census number (Ne/N) was 0.57. Combining Ne/N with dispersal distances from a radio-tracking study, we calculated that neighborhood size was 62.2 ha, which included between 204 and 480 individuals. Our population genetic analysis (based on randomly amplified polymorphic DNA (RAPD) and microsatellite markers) showed relatively low levels of genetic differentiation (Qpopulations 0.070.10) between subpopulations and no inbreeding within subpopulations (f = 0.0003). These estimates of population subdivision translate into an effective migration rate (Nem) of 2.33.3 per year, which represents a high level of gene flow. Invasion by exotics will reduce the overall productivity of the habitat, and will lead to isolation among subpopulations if favorable habitat patches become isolated.
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Rigg, Khary K
2017-01-01
Despite the growing popularity of MDMA (ecstasy/molly) among African Americans, their motives for using the drug are still largely unknown. The purpose of this study was to identify and describe the most salient motivations for using MDMA among this understudied population. In-depth interviews (n = 15) were conducted with a sample of African American young adults in Southwest Florida between August 2014 and November 2015. The primary motivations for using MDMA included: (1) altering the effects of marijuana and alcohol; (2) lasting longer sexually; (3) enhancing sexual pleasure; and (4) facilitating "freaky" sexual experiences. This is the first study to directly examine MDMA motivations specifically among African American drug users, and findings shed light on why some African Americans use MDMA. A better understanding of why African Americans use this drug should help to inform prevention and harm-reduction efforts. Study findings show the need for health messages that include the potential consequences of mixing MDMA with other drugs, and engaging in high-risk sexual behaviors after taking MDMA. These data contrast with motivations (e.g., introspection, self-enlightenment, getting into the music) commonly reported among groups of largely White MDMA users, suggesting that interventions tailored specifically for African American users are needed.
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Tadiri, Christina P; Dargent, Felipe; Scott, Marilyn E
2013-03-01
Understanding disease transmission is important to species management and human health. Host body condition, nutrition and disease susceptibility interact in a complex manner, and while the individual effects of these variables are well known, our understanding of how they interact and translate to population dynamics is limited. Our objective was to determine whether host relative body condition influences epidemic dynamics, and how this relationship is affected by food availability. Poecilia reticulata (guppies) of roughly similar size were selected and assembled randomly into populations of 10 guppies assigned to 3 different food availability treatments, and the relative condition index (Kn) of each fish was calculated. We infected 1 individual per group ('source' fish) with Gyrodactyus turnbulli and counted parasites on each fish every other day for 10 days. Epidemic parameters for each population were analysed using generalized linear models. High host Kn-particularly that of the 'source' fish-exerted a positive effect on incidence, peak parasite burden, and the degree of parasite aggregation. Low food availability increased the strength of the associations with peak burden and aggregation. Our findings suggest that host Kn and food availability interact to influence epidemic dynamics, and that the condition of the individual that brings the parasite into the host population has a profound impact on the spread of infection.
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Tomkins, Patrick; Saaristo, Minna; Bertram, Michael G; Tomkins, Raymond B; Allinson, Mayumi; Wong, Bob B M
2017-11-01
Despite a growing literature highlighting the potential impact of human-induced environmental change on mechanisms of sexual selection, relatively little is known about the effects of chemical pollutants on male-male competition. One class of environmental pollutant likely to impact male competitive interactions is the endocrine-disrupting chemicals (EDCs), a large and heterogeneous group of chemical contaminants with the potential to influence morphology, physiology and behaviour at minute concentrations. One EDC of increasing concern is the synthetic, androgenic steroid 17β-trenbolone, which is used globally to promote growth in beef cattle. Although 17β-trenbolone has been found to cause severe morphological and behavioural abnormalities in fish, its potential impact on male-male competition has yet to be investigated. To address this, we exposed wild male guppies (Poecilia reticulata) to an environmentally realistic concentration of 17β-trenbolone (average measured concentration: 8 ng/L) for 21 days using a flow-through system. We found that, in the presence of a competitor, 17β-trenbolone-exposed males carried out more frequent aggressive behaviours towards rival males than did unexposed males, as well as performing less courting behaviour and more sneak (i.e., coercive) mating attempts towards females. Considering that, by influencing mating outcomes, male-male competition has important consequences for population dynamics and broader evolutionary processes, this study highlights the need for greater understanding of the potential impact of EDCs on the mechanisms of sexual selection. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
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Passow, Courtney N.; Brown, Anthony P.; Arias-Rodriguez, Lenin; Yee, Muh-Ching; Sockell, Alexandra; Schartl, Manfred; Warren, Wesley C.; Bustamante, Carlos; Kelley, Joanna L.; Tobler, Michael
2017-01-01
Variation in gene expression can provide insights into organismal responses to environmental stress and physiological mechanisms mediating adaptation to habitats with contrasting environmental conditions. We performed an RNA-sequencing experiment to quantify gene expression patterns in fish adapted to habitats with different combinations of environmental stressors, including the presence of toxic hydrogen sulphide (H2S) and the absence of light in caves. We specifically asked how gene expression varies among populations living in different habitats, whether population differences were consistent among organs, and whether there is evidence for shared expression responses in populations exposed to the same stressors. We analysed organ-specific transcriptome-wide data from four ecotypes of Poecilia mexicana (nonsulphidic surface, sulphidic surface, nonsulphidic cave and sulphidic cave). The majority of variation in gene expression was correlated with organ type, and the presence of specific environmental stressors elicited unique expression differences among organs. Shared patterns of gene expression between populations exposed to the same environmental stressors increased with levels of organismal organization (from transcript to gene to physiological pathway). In addition, shared patterns of gene expression were more common between populations from sulphidic than populations from cave habitats, potentially indicating that physiochemical stressors with clear biochemical consequences can constrain the diversity of adaptive solutions that mitigate their adverse effects. Overall, our analyses provided insights into transcriptional variation in a unique system, in which adaptation to H2S and darkness coincide. Functional annotations of differentially expressed genes provide a springboard for investigating physiological mechanisms putatively underlying adaptation to extreme environments. PMID:28598519
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Gheorghiu, Cristina; Cable, Joanne; Marcogliese, David J; Scott, Marilyn E
2007-03-01
Recent reviews indicate that pollutants in the surrounding macroenvironment directly influence the population dynamics, distribution and dispersal of fish ectoparasites, often leading to increased parasitism. The aim of the current study was to explore the effects of sublethal concentrations of waterborne zinc (up to 240 microg Zn/L) on survival, reproduction and morphometrics of Gyrodactylus turnbulli, a viviparous monogenean infecting the skin and fins of the guppy, Poecilia reticulata. Parasite survival and reproduction on the fish were recorded daily for individual parasites maintained in isolated containers. Both survival and reproduction were reduced in 30 and 120 microg Zn/L, compared with 0, 15, and 60 microg Zn/L indicating direct toxic effects of Zn on the parasite. However, as generation time was unaffected by Zn, we attribute the reduced reproduction to the shorter lifespan. Parasite survival off the fish was monitored hourly. Average lifespan of the detached parasites decreased linearly from 19.5 h in 0 microg Zn/L to 17.3h in 240 microg Zn/L, further supporting the direct toxic effect of Zn to the parasite. In addition, temporal dynamics of parasite morphometrics were monitored from mini-epidemics sampled after 1, 5, 10, and 15 days exposure to various Zn concentrations. All morphological parameters decreased significantly in response both to concentration and duration of exposure to waterborne Zn. Together these data clearly indicate that concentrations as low as 120 microg Zn/L are directly toxic to G. turnbulli.
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Zhao, Lei; Li, Songnan; Ma, Xiaohai; Greiser, Andreas; Zhang, Tianjing; An, Jing; Bai, Rong; Dong, Jianzeng; Fan, Zhanming
2016-03-15
T1 mapping enables assessment of myocardial characteristics. As the most common type of arrhythmia, atrial fibrillation (AF) is often accompanied by a variety of cardiac pathologies, whereby the irregular and usually rapid ventricle rate of AF may cause inaccurate T1 estimation due to mis-triggering and inadequate magnetization recovery. We hypothesized that systolic T1 mapping with a heart-rate-dependent (HRD) pulse sequence scheme may overcome this issue. 30 patients with AF and 13 healthy volunteers were enrolled and underwent cardiovascular magnetic resonance (CMR) at 3 T. CMR was repeated for 3 patients after electric cardioversion and for 2 volunteers after lowering heart rate (HR). A Modified Look-Locker Inversion Recovery (MOLLI) sequence was acquired before and 15 min after administration of 0.1 mmol/kg gadopentetate dimeglumine. For AF patients, both the fixed 5(3)3/4(1)3(1)2 and the HRD sampling scheme were performed at diastole and systole, respectively. The HRD pulse sequence sampling scheme was 5(n)3/4(n)3(n)2, where n was determined by the heart rate to ensure adequate magnetization recovery. Image quality of T1 maps was assessed. T1 times were measured in myocardium and blood. Extracellular volume fraction (ECV) was calculated. In volunteers with repeated T1 mapping, the myocardial native T1 and ECV generated from the 1st fixed sampling scheme were smaller than from the 1st HRD and 2nd fixed sampling scheme. In healthy volunteers, the overall native T1 times and ECV of the left ventricle (LV) in diastolic T1 maps were greater than in systolic T1 maps (P < 0.01, P < 0.05). In the 3 AF patients that had received electrical cardioversion therapy, the myocardial native T1 times and ECV generated from the fixed sampling scheme were smaller than in the 1st and 2nd HRD sampling scheme (all P < 0.05). In patients with AF (HR: 88 ± 20 bpm, HR fluctuation: 12 ± 9 bpm), more T1 maps with artifact were found in diastole than in systole (P
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Reasons for the Invasive Success of a Guppy (Poecilia reticulata) Population in Trinidad
Sievers, Caya; Willing, Eva-Maria; Hoffmann, Margarete; Dreyer, Christine; Ramnarine, Indar; Magurran, Anne
2012-01-01
The introduction of non-native species into new habitats poses a major threat to native populations. Of particular interest, though often overlooked, are introductions of populations that are not fully reproductively isolated from native individuals and can hybridize with them. To address this important topic we used different approaches in a multi-pronged study, combining the effects of mate choice, shoaling behaviour and genetics. Here we present evidence that behavioural traits such as shoaling and mate choice can promote population mixing if individuals do not distinguish between native and foreign conspecifics. We examined this in the context of two guppy (Poecilia reticulata) populations that have been subject to an introduction and subsequent population mixing event in Trinidad. The introduction of Guanapo River guppies into the Turure River more than 50 years ago led to a marked reduction of the original genotype. In our experiments, female guppies did not distinguish between shoaling partners when given the choice between native and foreign individuals. Introduced fish are therefore likely to benefit from the protection of a shoal and will improve their survival chances as a result. The additional finding that male guppies do not discriminate between females on the basis of origin will further increase the process of population mixing, especially if males encounter mixed shoals. In a mesocosm experiment, in which the native and foreign populations were allowed to mate freely, we found, as expected on the basis of these behavioural interactions, that the distribution of offspring genotypes could be predicted from the proportions of the two types of founding fish. This result suggests that stochastic and environmental processes have reinforced the biological ones to bring about the genetic dominance of the invading population in the Turure River. Re-sampling the Turure for genetic analysis using SNP markers confirmed the population mixing process and showed
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Long, Kyle A; Nossa, Carlos W; Sewell, Mary A; Putnam, Nicholas H; Ryan, Joseph F
2016-01-01
There are five major extant groups of Echinodermata: Crinoidea (feather stars and sea lillies), Ophiuroidea (brittle stars and basket stars), Asteroidea (sea stars), Echinoidea (sea urchins, sea biscuits, and sand dollars), and Holothuroidea (sea cucumbers). These animals are known for their pentaradial symmetry as adults, unique water vascular system, mutable collagenous tissues, and endoskeletons of high magnesium calcite. To our knowledge, the only echinoderm species with a genome sequence available to date is Strongylocentrotus pupuratus (Echinoidea). The availability of additional echinoderm genome sequences is crucial for understanding the biology of these animals. Here we present assembled draft genomes of the brittle star Ophionereis fasciata, the sea star Patiriella regularis, and the sea cucumber Australostichopus mollis from Illumina sequence data with coverages of 12.5x, 22.5x, and 21.4x, respectively. These data provide a resource for mining gene superfamilies, identifying non-coding RNAs, confirming gene losses, and designing experimental constructs. They will be important comparative resources for future genomic studies in echinoderms.
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Scoppettone, G. Gary; Rissler, Peter; Johnson, Danielle; Hereford, Mark
2011-01-01
This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red
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Subtle Microbiome Manipulation Using Probiotics Reduces Antibiotic-Associated Mortality in Fish
Schmidt, Victor; Gomez-Chiarri, Marta; Roy, Chelsea; Smith, Katherine
2017-01-01
ABSTRACT Prophylactic antibiotics in the aquaculture and ornamental fish industry are intended to prevent the negative impacts of disease outbreaks. Research in mice and humans suggests that antibiotics may disturb microbiome communities and decrease microbiome-mediated disease resistance, also known as “colonization resistance.” If antibiotics impact fish as they do mice and humans, prophylactic administrations on aquaculture farms may increase downstream disease susceptibility in target hosts, despite short-term pathogen control benefits. We tested the effects of antibiotics on mortality after a pathogen challenge in the Poecilia sphenops black molly and subsequently tested if probiotic inoculations could reverse any antibiotic-induced losses of disease resistance. We found that antibiotic treatment significantly increased fish mortality. We further found that our two candidate probiotic bacterial species, Phaeobacter inhibens S4Sm and Bacillus pumilus RI06-95Sm, were able to colonize black molly microbiomes and reverse the negative impacts of antibiotics. Despite the positive impact on survival, probiotic treatment did not influence overall microbiome community structure or diversity. Our results suggest that subtle manipulations of microbiome composition can have dramatic impacts on host phenotype. The results of this study have implications for how antibiotic-treated microbiomes can be restored and suggest that small-scale additions may be as effective as wholesale transplants. IMPORTANCE Prophylactic antibiotics are widespread in the aquaculture industry and are used where vaccination is impossible or overly expensive. If antibiotics impact fish as they do mice and humans, prophylactic administrations in aquaculture and ornamental fish farms may increase downstream disease susceptibility in target hosts, despite short-term pathogen control benefits. Recent research has suggested that their use exacerbates bacterial outbreaks by creating sterile, nutrient
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Penshorn, Marina; Hamfler, Sybille; Herbert, Denise B.; Appel, Jessica; Meyer, Philipp; Slattery, Patrick; Charaf, Sarah; Wolf, Raoul; Völker, Johannes; Berger, Elisabeth A. M.; Dröge, Janis; Riesch, Rüdiger; Arias-Rodriguez, Lenin; Indy, Jeanne R.; Plath, Martin
2013-01-01
Ecological speciation assumes reproductive isolation to be the product of ecologically based divergent selection. Beside natural selection, sexual selection via phenotype-assortative mating is thought to promote reproductive isolation. Using the neotropical fish Poecilia mexicana from a system that has been described to undergo incipient ecological speciation in adjacent, but ecologically divergent habitats characterized by the presence or absence of toxic H2S and darkness in cave habitats, we demonstrate a gradual change in male body colouration along the gradient of light/darkness, including a reduction of ornaments that are under both inter- and intrasexual selection in surface populations. In dichotomous choice tests using video-animated stimuli, we found surface females to prefer males from their own population over the cave phenotype. However, female cave fish, observed on site via infrared techniques, preferred to associate with surface males rather than size-matched cave males, likely reflecting the female preference for better-nourished (in this case: surface) males. Hence, divergent selection on body colouration indeed translates into phenotype-assortative mating in the surface ecotype, by selecting against potential migrant males. Female cave fish, by contrast, do not have a preference for the resident male phenotype, identifying natural selection against migrants imposed by the cave environment as the major driver of the observed reproductive isolation. PMID:24175282
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Oliveira, Weslley F; Silva, Germana M M; Cabral Filho, Paulo E; Fontes, Adriana; Oliveira, Maria D L; Andrade, César A S; Silva, Márcia V; Coelho, Luana C B B; Machado, Giovanna; Correia, Maria T S
2018-09-01
An alternative to accelerate the osseointegration on titanium dioxide nanotubes (TNTs) used in osseointegrated implants is through the functionalization of these nanostructured surfaces with biomolecules. In this work, we immobilized a lectin with recognized mitogenic activity, the Cramoll lectin, extracted from Cratylia mollis seeds, on surfaces modified by TNTs. For the immobilization of Cramoll on TNTs surfaces, we used the Layer-by-Layer technique (LbL) by growing five alternate layers of poly(allylamine) hydrochloride (PAH) and poly(acrylic) acid (PAA); lastly we incubated the lectin, at different concentrations, with the TNTs-LbL. Before and after the immobilization procedures, the substrate surfaces were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and, electrochemical impedance spectroscopy (EIS). We also evaluated the Cramoll activity after immobilization on TNTs by using the lectin interaction with ovalbumin. The lectin did not lose its biological activity, even after immobilization onto nanotubular arrays. In addition, we observed an increase osteoblast-like cell adhesion on the TNTs-LbL-Cramoll system when compared to the bare TNTs surfaces. Moreover, a significative cell proliferation was identified on the substrates when Cramoll was immobilized at concentrations of 80, 160 and 320 μg/mL after 48 h of incubation by using the resazurin assay. Our results suggest that Cramoll was efficiently immobilized on a nanotubular array and this new platform presents a great potential to be tested in implantology. Copyright © 2018 Elsevier B.V. All rights reserved.
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Fridman, S; Sinai, T; Zilberg, D
2014-06-16
Monogenean infections of commercially farmed fishes are responsible for significant economic losses. Garlic (Allium sativum) is a well-known spice which also possesses anti-microbial and anti-parasitical properties. The current work aimed to test the efficacy of garlic-based treatments against infection with monogenean sp. in the guppy (Poecilia reticulata). Clipped sections of tail fins of guppies heavily infected with Gyrodactylus turnbulli were exposed to aqueous garlic extract (7.5 to 30 mL L(-1)) and visually observed under a dissecting microscope. Results revealed that exposure to garlic caused detachment of parasite and cessation of movement indicating death. A positive correlation was seen between garlic concentration and time to detachment and death of parasites, which, at the highest concentration of 30 mL L(-1), occurred at 4.1 and 8.6 min, respectively. Bathing in aqueous garlic extract (7.5 and 12.5 mL L(-1)) was tested in guppies infected with G. turnbulli. Prior acute toxicity tests revealed the maximum tolerance levels of guppies to garlic extract to be 12.5 mL L(-1) for 1h. Bathing of infected fish in garlic extract (7.5 and 12.5 mL L(-1)) significantly (p<0.05) reduced infection prevalence and intensity as compared to the control. Oral treatments using dry garlic powder-supplemented diet were tested on guppies infected with G. turnbulli and Dactylogyrus sp. Fish were fed with food containing 10% and 20% dry garlic powder for 14 days. Groups fed with garlic supplemented diets showed significantly reduced (p<0.05) mean prevalence and mean intensity of parasites as compared to the control. Dietary application of garlic did not appear to affect palatability. Fresh crushed garlic was added at a level of 1 gL(-1) and applied as an indefinite bath for 14 days. This treatment was seen to significantly reduce (p<0.05) parasite prevalence and mean intensity as compared to the control. Histopathology revealed elevated muscular dystrophy in the 20% garlic
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Pitcher, Trevor E; Rodd, F Helen; Rowe, Locke
2008-09-01
Several studies suggest that females may offset the costs of genetic incompatibility by exercising pre-copulatory or post-copulatory mate choice to bias paternity toward more compatible males. One source of genetic incompatibility is the degree of relatedness among mates; unrelated males are expected to be genetically more compatible with a female than her relatives. To address this idea, we investigated the potential for inbreeding depression and paternity biasing mechanisms (pre- and post-copulatory) of inbreeding avoidance in the guppy, Poecilia reticulata. Inbreeding resulted in a reduction in offspring number and quality. Females mated to siblings gave birth to significantly fewer offspring compared to females mated to non-siblings and inbred male offspring took longer to reach sexual maturity. There was no evidence of inbreeding avoidance in pre-copulatory behaviors of females or males. Sexual responsiveness of females to courting males and the number of sexual behaviors males directed at females did not decrease as a function of the relatedness of the two individuals. We also tested whether female guppies can use post-copulatory mechanisms to bias sperm usage toward unrelated males by comparing the number of offspring produced by females mated to two of their siblings (SS), two males unrelated to the female (NN), or to one unrelated male and a sibling male (NS). We found that NS females produced a number of offspring not significantly different than what would be expected if fertilization success were halfway between completely outbreeding (NN) and completely inbreeding (SS) females. This suggests that there is no significant improvement in the number of offspring produced by females mating to both related and unrelated males, relative to that which would be expected if sperm from both males were used equally. Our results suggest that female guppies do not discriminate against closely related males or their sperm.
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NASA Astrophysics Data System (ADS)
Morgan, Andrew; Neal, Lance
2012-07-01
For deeper regions of the continental shelf environmental cues entraining reproduction in echinoderms are often absent, which contributes to adoption of continuous reproduction, having larger eggs, and a lecithotrophic mode of larval development. In the present study the sub-Antarctic sea cucumber Pseudostichopus mollis from the family Synallactidae was obtained during June (winter) and September (spring) from a depth of approximately 300 m north of the Auckland Islands in an area abundant in biogenic sediments. Samples were processed for body indices and gonad development. Features characteristic of non-continuous reproduction were exhibited. Although a larger egg size was found (212±14 μm), two distinct winter cohorts of oocytes occurred (41-81 and 161-201 μm) and body wall weight fluctuations (7.6% increase in males and 27.5% reduction in females) coincided with changes in gonad indices between sample dates. For males gonad as a proportion of body wall weight decreased from 3.31±0.9 to 2.11±0.37% and for females it increased from 1.59±0.28 to 2.5±0.30%. For both sample dates the gonad of males maintained mature spermatozoa whereas female gonad shifted from mainly recovery and growth of oocytes to growth and advanced growth of mature oocytes. In habitats with low or variable food availability intermittent reproduction is predicted as resources are too low for a high reproductive effort and too erratic for synchrony. A pattern of reproduction where fluctuations in seasonal organic input into an accumulated benthic food source initiates and synchronises gametogenesis for future spawning is proposed.
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Tian, Hua; Wu, Peng; Wang, Wei; Ru, Shaoguo
2015-05-01
Although bioaccumulation of tributyltin (TBT) in fish has been confirmed, information on possible effects of TBT on reproductive system of fish is still relatively scarce, particularly at environmentally relevant levels. To evaluate the adverse effects and intrinsic toxicological properties of TBT in male fish, we studied aromatase gene expression in the brain, sex steroid contents, primary and secondary sexual characteristics, and reproductive behavior in male guppies (Poecilia reticulata) exposed to tributyltin chloride at the nominal concentrations of 5, 50, and 500 ng/L for 28 days in a semi-static exposure system. Radioimmunoassay demonstrated that treatment with 50 ng/L TBT caused an increase in systemic levels of testosterone of male guppies. Gonopodial index, which showed a positive correlation with testosterone levels, was elevated in the 5 ng/L and 50 ng/L TBT treated groups. Real-time PCR revealed that TBT exposure had inhibiting effects on expression of two isoforms of guppy aromatase in the brain, and these changes at the molecular levels were associated with a disturbance of reproductive behavior of the individuals, as measured by decreases in frequencies of posturing, sigmoid display, and chase activities when males were paired with females. This study provides the first evidence that TBT can cause abnormalities of secondary sexual characteristics in teleosts and that suppression of reproductive behavior in teleosts by TBT is due to its endocrine-disrupting action as an aromatase inhibitor targeting the nervous system. Copyright © 2015 Elsevier B.V. All rights reserved.
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Underreporting of ecstasy use among high school seniors in the US.
Palamar, Joseph J; Keyes, Katherine; Cleland, Charles M
2016-08-01
National surveys suggest ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) use has decreased substantially among adolescents in the US since 2001; however, the recent phenomenon of "Molly" (ecstasy marketed as "pure MDMA") may be leading to underreporting of use as not all users are aware that "Molly" is a form of ecstasy. We examined 2014 data from Monitoring the Future, a nationally representative survey of high school seniors in the US (N=6250, modal age: 18). Three randomly distributed survey forms asked about ecstasy use, and one included "Molly" in the definition. Self-reported lifetime, 12-month, and 30-day ecstasy use were compared to determine whether including "Molly" in the definition was associated with higher prevalence or frequency of use. The form including "Molly" in the definition had significantly higher prevalence than the two (combined) forms that did not. Lifetime use (8.0% vs. 5.5%) and 12-month use (5.1% vs. 3.6%) were significantly higher with "Molly" in the definition. Lifetime prevalence remained higher with "Molly" in the definition when controlling for correlates of ecstasy use; however, 12-month use did not. Differences in prevalence were associated with lifetime occasions of use, with lower concordance between forms at lower levels of lifetime occasions (e.g., 1-2 times). Survey form was not related to number of times used among more frequent users. Prevalence of ecstasy use appears to be underestimated when "Molly" is not included in the definition of ecstasy/MDMA. Surveys should include "Molly" in the definition of ecstasy to more adequately assess prevalence of use. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
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Plath, M; Hauswaldt, J S; Moll, K; Tobler, M; García De León, F J; Schlupp, I; Tiedemann, R
2007-03-01
We investigated genetic differentiation and migration patterns in a small livebearing fish, Poecilia mexicana, inhabiting a sulfidic Mexican limestone cave (Cueva del Azufre). We examined fish from three different cave chambers, the sulfidic surface creek draining the cave (El Azufre) and a nearby surface creek without the toxic hydrogen sulphide (Arroyo Cristal). Using microsatellite analysis of 10 unlinked loci, we found pronounced genetic differentiation among the three major habitats: Arroyo Cristal, El Azufre and the cave. Genetic differentiation was also found within the cave between different pools. An estimation of first-generation migrants suggests that (i) migration is unidirectional, out of the cave, and (ii) migration among different cave chambers occurs to some extent. We investigated if the pattern of genetic differentiation is also reflected in a morphological trait, eye size. Relatively large eyes were found in surface habitats, small eyes in the anterior cave chambers, and the smallest eyes were detected in the innermost cave chamber (XIII). This pattern shows some congruence with a previously proposed morphocline in eye size. However, our data do not support the proposed mechanism for this morphocline, namely that it would be maintained by migration from both directions into the middle cave chambers. This would have led to an increased variance in eye size in the middle cave chambers, which we did not find. Restricted gene flow between the cave and the surface can be explained by local adaptations to extreme environmental conditions, namely H2S and absence of light. Within the cave system, habitat properties are patchy, and genetic differentiation between cave chambers despite migration could indicate local adaptation at an even smaller scale.
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Sharon, Galit; Nath, Pulak R; Isakov, Noah; Zilberg, Dina
2014-09-15
Analysis of the effectiveness of guppy (Poecilia reticulata Peters) immunization based on measurements of antibody (Ab) titers suffers from a shortage of reagents that can detect guppy antibodies (Abs). To overcome this problem, we immunized mice with different preparations of guppy immunoglobulins (Igs) and used the mouse antisera to develop a quantitative enzyme-linked immunosorbent assay (ELISA). The most efficient immunogen for mouse immunization was guppy Igs adsorbed on protein A/G beads. Antisera from mice boosted with this immunoglobulin (Ig) preparation were highly specific and contained high Ab titers. They immunoreacted in a Western blot with Ig heavy and light chains from guppy serum, and Ig heavy chain from guppy whole-body homogenate. The mouse anti-guppy Ig was applied in an ELISA aimed at comparing the efficiency of different routes of guppy immunization against Tetrahymena: (i) anal intubation with sonicated Tetrahymena (40,000 Tetrahymena/fish in a total volume of 10 μL) mixed with domperidon, deoxycholic acid and free amino acids (valine, leucine, isoleucine, phenylalanine and tryptophan), or (ii) intraperitoneal (i.p.) injection of sonicated Tetrahymena in complete Freund's adjuvant (15,000 Tetrahymena/fish in total a volume of 20 μL). Negative control fish were anally intubated with the intubation mixture without Tetrahymena, or untreated. ELISA measurement of anti-Tetrahymena Ab titer revealed a significantly higher level of Abs in i.p.-immunized guppies, compared to the anally intubated and control fish. In addition, the efficiency of immunization was tested by monitoring guppy mortality following (i) i.p. challenge with Tetrahymena (900 Tetrahymena/fish) or (ii) cold stress followed by immersion in water containing 10,000 Tetrahymena/mL. Fish mortality on day 14 post-Tetrahymena infection by i.p. injection exceeded 50% in the control and anally intubated fish, compared to 31% in i.p.-immunized fish. Immunization did not protect from
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Shao, Jiaxin; Rapacchi, Stanislas; Nguyen, Kim-Lien; Hu, Peng
2016-02-01
To develop an accurate and precise myocardial T1 mapping technique using an inversion recovery spoiled gradient echo readout at 3.0 Tesla (T). The modified Look-Locker inversion-recovery (MOLLI) sequence was modified to use fast low angle shot (FLASH) readout, incorporating a BLESSPC (Bloch Equation Simulation with Slice Profile Correction) T1 estimation algorithm, for accurate myocardial T1 mapping. The FLASH-MOLLI with BLESSPC fitting was compared with different approaches and sequences with regards to T1 estimation accuracy, precision and image artifact based on simulation, phantom studies, and in vivo studies of 10 healthy volunteers and three patients at 3.0 Tesla. The FLASH-MOLLI with BLESSPC fitting yields accurate T1 estimation (average error = -5.4 ± 15.1 ms, percentage error = -0.5% ± 1.2%) for T1 from 236-1852 ms and heart rate from 40-100 bpm in phantom studies. The FLASH-MOLLI sequence prevented off-resonance artifacts in all 10 healthy volunteers at 3.0T. In vivo, there was no significant difference between FLASH-MOLLI-derived myocardial T1 values and "ShMOLLI+IE" derived values (1458.9 ± 20.9 ms versus 1464.1 ± 6.8 ms, P = 0.50); However, the average precision by FLASH-MOLLI was significantly better than that generated by "ShMOLLI+IE" (1.84 ± 0.36% variance versus 3.57 ± 0.94%, P < 0.001). The FLASH-MOLLI with BLESSPC fitting yields accurate and precise T1 estimation, and eliminates banding artifacts associated with bSSFP at 3.0T. © 2015 Wiley Periodicals, Inc.
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Scenes of Devastation: Chasing Hawaii's Deadly Ohia Fungus | Hawaii Public
Scenes of Devastation: Chasing Hawaii's Deadly Ohia Fungus By Molly Solomon * Mar 25, 2016 TweetShareGoogle+Email Molly Solomon Rapid Ohia Death has devastated native forests on Hawaii Island, especially in Lower Puna subdivisions like Leilani Estates. Credit Molly Solomon One of Hawai'i's oldest and most
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Palacios, Maura; Arias-Rodriguez, Lenin; Plath, Martin; Eifert, Constanze; Lerp, Hannes; Lamboj, Anton; Voelker, Gary; Tobler, Michael
2013-01-01
The process of ecological speciation drives the evolution of locally adapted and reproductively isolated populations in response to divergent natural selection. In Southern Mexico, several lineages of the freshwater fish species of the genus Poecilia have independently colonized toxic, hydrogen sulfide-rich springs. Even though ecological speciation processes are increasingly well understood in this system, aligning the taxonomy of these fish with evolutionary processes has lagged behind. While some sulfide spring populations are classified as ecotypes of Poecilia mexicana, others, like P. sulphuraria, have been described as highly endemic species. Our study particularly focused on elucidating the taxonomy of the long described sulfide spring endemic, Poecilia thermalis Steindachner 1863, and investigates if similar evolutionary patterns of phenotypic trait divergence and reproductive isolation are present as observed in other sulfidic species of Poecilia. We applied a geometric morphometric approach to assess body shape similarity to other sulfidic and non-sulfidic fish of the genus Poecilia. We also conducted phylogenetic and population genetic analyses to establish the phylogenetic relationships of P. thermalis and used a population genetic approach to determine levels of gene flow among Poecilia from sulfidic and non-sulfidic sites. Our results indicate that P. thermalis' body shape has evolved in convergence with other sulfide spring populations in the genus. Phylogenetic analyses placed P. thermalis as most closely related to one population of P. sulphuraria, and population genetic analyses demonstrated that P. thermalis is genetically isolated from both P. mexicana ecotypes and P. sulphuraria. Based on these findings, we make taxonomic recommendations for P. thermalis. Overall, our study verifies the role of hydrogen sulfide as a main factor shaping convergent, phenotypic evolution and the emergence of reproductive isolation between Poecilia populations
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Davies, Keith G; Zimmerman, Brian; Dudley, Ed; Newton, Russell P; Hart, John E
2015-03-01
Ambient exposure to a short synthetic peptide has enhanced fecundity (number of offspring) in invertebrates and vertebrates, ostensibly by disinhibiting reproduction. In separate experiments, nematodes (Caenorhabditis elegans) and guppy fish (Poecilia reticulata) were exposed via their aqueous environment to a dissolved synthetic hexamer (6mer) peptide, IEPVFT (EPL036), at a concentration of 1 μmol l(-1). In the case of the worms, peptide was added to their aqueous buffer daily throughout the experiment (14 days); for the guppies, peptide administration was on the first 15 alternate days in a 50 week experiment. Fecundity rose by 79% among the worms. The number of descendants of the treated guppies was more than four times that of controls by week 26 (103 versus 25, including 72 juveniles versus 6), with 15.4% more estimated biomass in the test tank in total (i.e. including founders). It was deduced that treated females bred earlier, at a smaller size, and had larger brood sizes. The total number of fish in the control tank had caught up by termination, but biomass continued to lag the test tank. There were no overt signs of toxicity among either the worms or the fish. Bioinformatics has been unilluminating in explaining these results in terms, for example, of mimicry of an endogenous regulator. A mass spectrometric campaign to identify a receptor, using murine brain for expediency, proved inconclusive. Molecular modelling in silico indicated unexpectedly that the hexamer EPL036 might be acting as an antagonist, to pro-fecundity effect; that is, as a blocker of an inhibitor. This suggests that there awaits discovery an evolutionarily conserved reproductive inhibitor and its (anti-fecundity) receptor. © 2015. Published by The Company of Biologists Ltd.
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Effects of competition on induction of crassulacean acid metabolism in a facultative CAM plant.
Yu, Kailiang; D'Odorico, Paolo; Li, Wei; He, Yongli
2017-06-01
Abiotic drivers of environmental stress have been found to induce CAM expression (nocturnal carboxylation) in facultative CAM species such as Mesembryanthemum crystallinum. The role played by biotic factors such as competition with non-CAM species in affecting CAM expression, however, remains largely understudied. This research investigated the effects of salt and water conditions on the competition between M. crystallinum and the C 3 grass Bromus mollis with which it is found to coexist in California's coastal grasslands. We also investigated the extent to which CAM expression in M. crystallinum was affected by the intensity of the competition with B. mollis. We found that M. crystallinum had a competitive advantage over B. mollis in drought and saline conditions, while B. mollis exerted strong competitive effects on M. crystallinum in access to light and soil nutrients in high water conditions. This strong competitive effect even outweighed the favorable effects of salt or water additions in increasing the biomass and productivity of M. crystallinum in mixture. Regardless of salt conditions, M. crystallinum did not switch to CAM photosynthesis in response to this strong competitive effect from B. mollis. Disturbance (i.e., grass cutting) reduced the competitive pressure by B. mollis and allowed for CAM expression in M. crystallinum when it was grown mixed with B. mollis. We suggest that moderate competition with other functional groups can enhance CAM expression in M. crystallinum, thereby affecting its plasticity and ability to cope with biological stress.
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Volkova, Kristina; Reyhanian, Nasim; Kot-Wasik, Agata; Olsén, Håkan; Porsch-Hällström, Inger; Hallgren, Stefan
2012-09-01
The effects of endocrine disruptors may vary with the timing of exposure. The physiological implications of adult exposure are present during and shortly after exposure while embryonic exposure can imprint changes manifested in adulthood. In this study, guppy (Poecilia reticulata) embryos were exposed to 2 and 20 ng/L of 17α-ethinylestradiol during development via the mother and reared in clean water from gestation until 6 months of age. As adults, fish exposed to 20 ng/L during development showed significantly altered behaviour in the Novel Tank test, where anxiety is determined as the tendency to remain at the bottom upon introduction into an unfamiliar tank. 17α-ethinylestradiol treatment increased the latency time before swimming to the upper half of the tank and decreased the number of transitions to the upper half. In control females the basal stress behaviour responses were significantly higher than in males, as indicated by longer latency period and fewer and shorter visits to the upper half, supporting the importance of gonadal hormones for the behaviour. The anxiety increased, however, with treatment in both sexes, suggesting that the observed response is not entirely due to feminisation of the males. Shoaling behaviour, analysed as tendency to leave a shoal of littermates, was neither sex-differentiated nor changed by treatment. Also male reproductive behaviour, brain aromatase activity and testes histology, previously shown to respond to oestrogen exposure in adult guppy, were unaffected by the developmental treatment. This suggests that the stress system in the guppy is very sensitive to 17α-ethinylestradiol, which possibly causes an early organisational imprint on the brain circuit that regulates stress reactions. Copyright © 2012 Elsevier Inc. All rights reserved.
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Murugan, Kadarkarai; Venus, Joseph Selvaraj Eugine; Panneerselvam, Chellasamy; Bedini, Stefano; Conti, Barbara; Nicoletti, Marcello; Sarkar, Santosh Kumar; Hwang, Jiang-Shiou; Subramaniam, Jayapal; Madhiyazhagan, Pari; Kumar, Palanisamy Mahesh; Dinesh, Devakumar; Suresh, Udaiyan; Benelli, Giovanni
2015-11-01
Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Furthermore, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. In this study, silver nanoparticles (AgN) were biosynthesized a cheap aqueous extract of T. asiatica leaves as reducing and stabilizing agent. The formation of nanoparticle was confirmed by surface Plasmon resonance band illustrated in UV-vis spectrophotometer. AgN were characterized by FTIR, SEM, EDX, and XRD analyses. AgN were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and their mean size was 25-30 nm. T. asiatica aqueous extract and green-synthesized AgN showed excellent larvicidal and pupicidal toxicity against the filariasis vector Culex quinqufasciatus, both in laboratory and field experiments. AgN LC50 ranged from 16.48 (I instar larvae) to 31.83 ppm (pupae). T. asiatica-synthesized were also highly effective in inhibiting growth of Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. Lastly, we evaluated if sublethal doses of nanoparticles affect predation rates of fishes, Poecilia reticulata, against C. quinquefasciatus. In AgN-contaminated environment, predation of guppies against mosquito larvae was slightly higher over normal laboratory conditions. Overall, this study highlighted that T. asiatica-synthesized AgN are easy to produce, stable over time, and may be employed at low dosages to reduce populations of filariasis vectors, without detrimental effects on predation rates of mosquito natural enemies.
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Bagley, Justin C.; Alda, Fernando; Breitman, M. Florencia; Bermingham, Eldredge; van den Berghe, Eric P.; Johnson, Jerald B.
2015-01-01
Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including ‘non-adaptive radiations’ containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci) from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial ‘major-lineages’ diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively) 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the importance of
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Bagley, Justin C; Alda, Fernando; Breitman, M Florencia; Bermingham, Eldredge; van den Berghe, Eric P; Johnson, Jerald B
2015-01-01
Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including 'non-adaptive radiations' containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci) from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial 'major-lineages' diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively) 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the importance of testing for
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Ghosh, Susanta K; Chakaravarthy, Preethi; Panch, Sandhya R; Krishnappa, Pushpalatha; Tiwari, Satyanarayan; Ojha, Vijay P; Manjushree, R; Dash, Aditya P
2011-07-28
In 2006, severe outbreaks of Aedes aegypti-transmitted chikungunya occurred in villages in Karnataka, South India. We evaluated the effectiveness of combined information, education and communication (IEC) campaigns using two potential poeciliid larvivorous fish guppy (Poecilia reticulata) and mosquitofish (Gambusia affinis), in indoor cement tanks for Aedes larval control. Trials were conducted in two villages (Domatmari and Srinivaspura) in Tumkur District from March to May 2006 for Poecilia and one village (Balmanda) in Kolar District from July to October 2006 for Gambusia. A survey on knowledge, attitude and practice (KAP) on chikungunya was initially conducted and IEC campaigns were performed before and after fish release in Domatmari (IEC alone, followed by IEC + Poecilia) and Balmanda (IEC + Gambusia). In Srinivaspura, IEC was not conducted. Larval surveys were conducted at the baseline followed by one-week and one-month post-intervention periods. The impact of fish on Aedes larvae and disease was assessed based on baseline and post-intervention observations. Only 18% of respondents knew of the role of mosquitoes in fever outbreaks, while almost all (n = 50 each) gained new knowledge from the IEC campaigns. In Domatmari, IEC alone was not effective (OR 0.54; p = 0.067). Indoor cement tanks were the most preferred Ae. aegypti breeding habitat (86.9%), and had a significant impact on Aedes breeding (Breteau Index) in all villages in the one-week period (p < 0.001). In the one-month period, the impact was most sustained in Domatmari (OR 1.58, p < 0.001) then Srinivaspura (OR 0.45, p = 0.063) and Balmanda (OR 0.51, p = 0.067). After fish introductions, chikungunya cases were reduced by 99.87% in Domatmari, 65.48% in Srinivaspura and 68.51% in Balmanda. Poecilia exhibited greater survival rates than Gambusia (86.04 vs.16.03%) in cement tanks. Neither IEC nor Poecilia alone was effective against Aedes (p > 0.05). We conclude that Poecilia + IEC is an effective
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Charan-Dixon, Hannah; Gaw, Sally; Goldstien, Sharyn J; Glover, Chris N
2017-07-01
The sea cucumber Stichopus horrens is an important component of near-shore ecosystems, and in the Kingdom of Tonga it also comprises an important commercial and subsistence fishery. To assess the sensitivity of this species to the toxic trace metal cadmium (Cd), adult S. horrens were exposed for 96h to an environmental (15µgL -1 ) or effect (765µgL -1 ) concentration of waterborne Cd. The respiratory tree and intestine accumulated higher concentrations of Cd than the muscle and body wall, but there were no effects of Cd on tissue ions (sodium, potassium, magnesium, calcium). For comparison, Cd accumulation was also examined in the Australasian sea cucumber Australostichopus mollis. This species displayed a similar pattern of tissue-specific accumulation to S. horrens, but exhibited lower tissue Cd burdens, likely a consequence of lower experimental temperature. Effects on gonad ion content were also seen in this species. At the highest Cd exposure concentration, S. horrens showed impaired ammonia excretion rates and an increased molar oxygen:nitrogen ratio (O:N), indicative of a decreased reliance on protein metabolism. Overall, this study suggests that S. horrens is relatively tolerant of Cd exposure, but raises concerns regarding the subsistence fishery practice of consuming the viscera of this species. Copyright © 2017 Elsevier Inc. All rights reserved.
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Baldwin, Alexander J
2018-04-16
Mollie Lentaigne was a medical artist who worked at the Queen Victoria Hospital in East Grinstead during the Second World War alongside Archibald McIndoe and his dedicated team. She drew hundreds of medical illustrations for McIndoe and his fellow surgeons during the years between 1940 and 1945. Her illustrations depict the plastic surgery that was carried out in that hospital on the badly burnt RAF servicemen injured during the war that took place in the skies over Europe, which included many aircrew injured during the Battle of Britain. This project looks at the career of Lentaigne and her role within the surgical team in East Grinstead during that era and explores a number of Lentaigne's illustrations whilst providing context as to the procedures and patients depicted. An examination of Lentaigne's story, using an interview conducted by the author with the artist offers an alternative perspective with which to observe the events that unfolded in East Grinstead during that conflict. An analysis of these images shows the ability of this artist to portray relatively complex operations with a series of simple pencil or ink diagrams whilst also skilfully engaging the observer's sense of touch. The ability of a medical artist to be selective with her illustrations allowed them to provide clearer, less cluttered images that were preferred by McIndoe when recording the specific surgical procedures for use in the patient's medical records. Copyright © 2018 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
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Bashey, Farrah
2006-02-01
The existence of adaptive phenotypic plasticity demands that we study the evolution of reaction norms, rather than just the evolution of fixed traits. This approach requires the examination of functional relationships among traits not only in a single environment but across environments and between traits and plasticity itself. In this study, I examined the interplay of plasticity and local adaptation of offspring size in the Trinidadian guppy, Poecilia reticulata. Guppies respond to food restriction by growing and reproducing less but also by producing larger offspring. This plastic difference in offspring size is of the same order of magnitude as evolved genetic differences among populations. Larger offspring sizes are thought to have evolved as an adaptation to the competitive environment faced by newborn guppies in some environments. If plastic responses to maternal food limitation can achieve the same fitness benefit, then why has guppy offspring size evolved at all? To explore this question, I examined the plastic response to food level of females from two natural populations that experience different selective environments. My goals were to examine whether the plastic responses to food level varied between populations, test the consequences of maternal manipulation of offspring size for offspring fitness, and assess whether costs of plasticity exist that could account for the evolution of mean offspring size across populations. In each population, full-sib sisters were exposed to either a low- or high-food treatment. Females from both populations produced larger, leaner offspring in response to food limitation. However, the population that was thought to have a history of selection for larger offspring was less plastic in its investment per offspring in response to maternal mass, maternal food level, and fecundity than the population under selection for small offspring size. To test the consequences of maternal manipulation of offspring size for offspring
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Selecting the Perfect Baby: The Ethics of Embryo Design.
ERIC Educational Resources Information Center
Omarzu, Julia
2002-01-01
Presents the real life story of Molly, who was born with a rare genetic disorder, and her parents' hope to cure her by having another child with specific genetic markers and using his/her stem cells to cure Molly. Addresses the ethical issues of genetic manipulation and fertility treatment. Includes teaching notes and classroom management…
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Predator-induced changes of female mating preferences: innate and experiential effects
2011-01-01
Background In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana). Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators. Results In dichotomous choice tests predator-naïve (lab-reared) females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus). In contrast, predator experienced (wild-caught) females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey. Conclusions Our study highlights that (a) predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection), and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b) Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c) Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators. PMID:21726456
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... and e-Cigarettes Will Protect Public Health Research Report MDMA (Ecstasy) Abuse Describes the science behind MDMA ( ... prevention and treatment of MDMA. Read more Research Report Hallucinogens and Dissociative Drugs Offers the latest research ...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Hua; Li, Yun; Wang, Wei
Monocrotophos is a highly toxic organophosphorus pesticide that has been confirmed to be an endocrine‐disrupting chemical. To evaluate the influence of this pollutant on the reproductive system of male fish, we studied the sex steroid levels, reproductive traits, sex ratio, and reproductive success in male guppies (Poecilia reticulata) exposed to 40% monocrotophos pesticide at the nominal concentrations of 0.01, 0.10, and 1.00 mg/L for 90 days from birth to adulthood in a semi‐static exposure system. Radioimmunoassay and western blot analyses demonstrated that the long‐term exposure to monocrotophos pesticide during the sexual development of male guppies caused a significant increase inmore » 17β‐estradiol levels and consequently induced vitellogenin synthesis, suggesting the feminization of the males. Monocrotophos pesticide also caused a significant decrease in testosterone levels, which consequently inhibited testis growth and reduced the sperm count and the area and intensity of their sexually attractive orange spots, which collectively indicated the significant demasculinization of the male sexual characteristics. Furthermore, these changes in the sexual characteristics at the cellular and organ levels translated into ecologically important effects on the reproductive success at the individual level, as measured by a decrease in offspring production and survival rate. The present study provides the first evidence that monocrotophos pesticide can cause severe reproductive abnormalities in fish due to its endocrine‐disrupting action. -- Highlights: ► Monocrotophos pesticide caused an increase in 17β‐estradiol levels of male guppies. ► Monocrotophos pesticide induced vitellogenin synthesis of male guppies. ► Monocrotophos pesticide caused a decrease in testosterone levels of male guppies. ► Monocrotophos pesticide caused demasculinization of male sexual characteristics. ► Monocrotophos pesticide caused a reduction in reproductive success
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Underwood, Joshua; Moch, John; Chen, Ming-Shun; Zhu, Lieceng
2014-10-01
Heat stress exerts significant impact on plant-parasite interactions. Phytohormones, such as salicylic acid (SA), play important roles in plant defense against parasite attacks. Here, we studied the impact of a combination of heat stress and exogenous SA on the resistance of wheat (Triticum aestivum L.) plants to the Hessian fly [Mayetiola destructor (Say)]. We found that the wheat cultivar 'Molly', which contains the resistance gene H13, lost resistance to Hessian fly under heat stress (40°C for 3 and 6 h), and that exogenous application of SA on Molly seedlings right before heat stress can partially prevent the loss of resistance of Molly plants under heat conditions. Our findings have significant implications for understanding the dynamics of plant-insect interactions in the context of heat stress. © 2014 Entomological Society of America.
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2010-01-01
Background Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre system in southern Mexico, where two strong environmental selection factors (darkness within caves and/or presence of toxic H2S in sulfidic springs) drive the diversification of P. mexicana. Nine nuclear microsatellites as well as heritable female life history traits (both as a proxy for quantitative genetics and for trait divergence) were used as markers to compare genetic differentiation, genetic diversity, and especially population mixing (immigration and emigration) before and after the flood. Results Habitat type (i.e., non-sulfidic surface, sulfidic surface, or sulfidic cave), but not geographic distance was the major predictor of genetic differentiation. Before and after the flood, each habitat type harbored a genetically distinct population. Only a weak signal of individual dislocation among ecologically divergent habitat types was uncovered (with the exception of slightly increased dislocation from the Cueva del Azufre into the sulfidic creek, El Azufre). By contrast, several lines of evidence are indicative of increased flood-induced dislocation within the same habitat type, e.g., between different cave chambers of the Cueva del Azufre. Conclusions The virtual absence of individual dislocation among ecologically different habitat types indicates strong natural selection against migrants. Thus, our current study exemplifies that ecological speciation in this and other systems, in which extreme environmental factors drive speciation, may be little affected by temporary
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Plath, Martin; Hermann, Bernd; Schröder, Christiane; Riesch, Rüdiger; Tobler, Michael; García de León, Francisco J; Schlupp, Ingo; Tiedemann, Ralph
2010-08-23
Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre system in southern Mexico, where two strong environmental selection factors (darkness within caves and/or presence of toxic H2S in sulfidic springs) drive the diversification of P. mexicana. Nine nuclear microsatellites as well as heritable female life history traits (both as a proxy for quantitative genetics and for trait divergence) were used as markers to compare genetic differentiation, genetic diversity, and especially population mixing (immigration and emigration) before and after the flood. Habitat type (i.e., non-sulfidic surface, sulfidic surface, or sulfidic cave), but not geographic distance was the major predictor of genetic differentiation. Before and after the flood, each habitat type harbored a genetically distinct population. Only a weak signal of individual dislocation among ecologically divergent habitat types was uncovered (with the exception of slightly increased dislocation from the Cueva del Azufre into the sulfidic creek, El Azufre). By contrast, several lines of evidence are indicative of increased flood-induced dislocation within the same habitat type, e.g., between different cave chambers of the Cueva del Azufre. The virtual absence of individual dislocation among ecologically different habitat types indicates strong natural selection against migrants. Thus, our current study exemplifies that ecological speciation in this and other systems, in which extreme environmental factors drive speciation, may be little affected by temporary perturbations, as adaptations
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2013-01-01
Background Cardiovascular magnetic resonance (CMR) T1 mapping indices, such as T1 time and partition coefficient (λ), have shown potential to assess diffuse myocardial fibrosis. The purpose of this study was to investigate how scanner and field strength variation affect the accuracy and precision/reproducibility of T1 mapping indices. Methods CMR studies were performed on two 1.5T and three 3T scanners. Eight phantoms were made to mimic the T1/T2 of pre- and post-contrast myocardium and blood at 1.5T and 3T. T1 mapping using MOLLI was performed with simulated heart rate of 40-100 bpm. Inversion recovery spin echo (IR-SE) was the reference standard for T1 determination. Accuracy was defined as the percent error between MOLLI and IR-SE, and scan/re-scan reproducibility was defined as the relative percent mean difference between repeat MOLLI scans. Partition coefficient was estimated by ΔR1myocardium phantom/ΔR1blood phantom. Generalized linear mixed model was used to compare the accuracy and precision/reproducibility of T1 and λ across field strength, scanners, and protocols. Results Field strength significantly affected MOLLI T1 accuracy (6.3% error for 1.5T vs. 10.8% error for 3T, p<0.001) but not λ accuracy (8.8% error for 1.5T vs. 8.0% error for 3T, p=0.11). Partition coefficients of MOLLI were not different between two 1.5T scanners (47.2% vs. 47.9%, p=0.13), and showed only slight variation across three 3T scanners (49.2% vs. 49.8% vs. 49.9%, p=0.016). Partition coefficient also had significantly lower percent error for precision (better scan/re-scan reproducibility) than measurement of individual T1 values (3.6% for λ vs. 4.3%-4.8% for T1 values, approximately, for pre/post blood and myocardium values). Conclusion Based on phantom studies, T1 errors using MOLLI ranged from 6-14% across various MR scanners while errors for partition coefficient were less (6-10%). Compared with absolute T1 times, partition coefficient showed less variability across
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... View Online Download PDF Monitoring the Future 2015 Survey Results Published: December 16, 2015 NIH’s 2015 Monitoring ... the National Drug and Alcohol Facts Week logo design are registered marks of the U.S. Department of ...
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-7758 Areas of Expertise Budget and Project Commercial Management Contracting and Risk Management Management Benchmarking and Industry Best Practices Education M.B.A., Regis University (Operations Management
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Convergent life-history shifts: toxic environments result in big babies in two clades of poeciliids
NASA Astrophysics Data System (ADS)
Riesch, Rüdiger; Plath, Martin; García de León, Francisco J.; Schlupp, Ingo
2010-02-01
The majority of studies on ecological speciation in animals have investigated the divergence caused by biotic factors like divergent food sources or predatory regimes. Here, we examined a system where ecological speciation can clearly be ascribed to abiotic environmental gradients of naturally occurring toxic hydrogen sulfide (H2S). In southern Mexico, two genera of livebearing fishes (Poeciliidae: Poecilia and Gambusia) thrive in various watercourses with different concentrations of H2S. Previous studies have revealed pronounced genetic differentiation between different locally adapted populations in one species ( Poecilia mexicana), pointing towards incipient speciation. In the present study, we examined female reproductive life-history traits in two species pairs: Gambusia sexradiata (from a nonsulfidic and a sulfidic habitat) and Gambusia eurystoma (sulfide-endemic), as well as P. mexicana (nonsulfidic and sulfidic) and Poecilia sulphuraria (sulfide endemic). We found convergent divergence of life-history traits in response to sulfide; most prominently, extremophile poeciliids exhibit drastically increased offspring size coupled with reduced fecundity. Furthermore, within each genus, this trend increased with increasing sulfide concentrations and was most pronounced in the two endemic sulfur-adapted species. We discuss the adaptive significance of large offspring size in toxic environments and propose that divergent life-history evolution may promote further ecological divergence through isolation by adaptation.
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Svendsen, Jon C.; Tirsgaard, Bjørn; Cordero, Gerardo A.; Steffensen, John F.
2015-01-01
Intraspecific variation and trade-off in aerobic and anaerobic traits remain poorly understood in aquatic locomotion. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), both axial swimmers, this study tested four hypotheses: (1) gait transition from steady to unsteady (i.e., burst-assisted) swimming is associated with anaerobic metabolism evidenced as excess post exercise oxygen consumption (EPOC); (2) variation in swimming performance (critical swimming speed; Ucrit) correlates with metabolic scope (MS) or anaerobic capacity (i.e., maximum EPOC); (3) there is a trade-off between maximum sustained swimming speed (Usus) and minimum cost of transport (COTmin); and (4) variation in Usus correlates positively with optimum swimming speed (Uopt; i.e., the speed that minimizes energy expenditure per unit of distance traveled). Data collection involved swimming respirometry and video analysis. Results showed that anaerobic swimming costs (i.e., EPOC) increase linearly with the number of bursts in S. aurata, with each burst corresponding to 0.53 mg O2 kg−1. Data are consistent with a previous study on striped surfperch (Embiotoca lateralis), a labriform swimmer, suggesting that the metabolic cost of burst swimming is similar across various types of locomotion. There was no correlation between Ucrit and MS or anaerobic capacity in S. aurata indicating that other factors, including morphological or biomechanical traits, influenced Ucrit. We found no evidence of a trade-off between Usus and COTmin. In fact, data revealed significant negative correlations between Usus and COTmin, suggesting that individuals with high Usus also exhibit low COTmin. Finally, there were positive correlations between Usus and Uopt. Our study demonstrates the energetic importance of anaerobic metabolism during unsteady swimming, and provides intraspecific evidence that superior maximum sustained swimming speed is associated with superior swimming economy and
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Currie, Yaleaka; Moch, John; Underwood, Joshua; Kharabsheh, Hamzah; Quesenberry, Amy; Miyagi, Risa; Thomas, Carolyn; Boney, Melanie; Woods, Samantha; Chen, Ming-Shun; Zhu, Lieceng
2014-02-01
Heat stress exerts a profound impact on the resistance of plants to parasites. In this research, we investigated the impact of an acute transient heat stress on the resistance of the wheat line 'Molly,' which contains the R gene H13, to an avirulent Hessian fly (Mayetiola destructor (Say)) population. We found that a significant portion of Molly seedlings stressed at 40 degrees C for 6 h during or after the initial Hessian fly larval attack became susceptible to otherwise avirulent insects, whereas unstressed control plants remained 100% resistant. Specifically, 77.8, 73.3, 83.3, and 46.7% of plants heat stressed at 0, 6,12, and 24 h, respectively, after the initial larval attack became susceptible. Biochemical analysis revealed that heat stress caused a transient decrease in 12-oxo-phytodienoic acid, but an increase in salicylic acid accumulation in Molly plants. The change in phytohormones after heat stress and Hessian fly infestation was not observed in 'Newton,' a near-isogenic but Hessian fly susceptible wheat line. Instead, heat stress caused a relatively prolonged reduction in palmitoleic acid. The role of phytohormones in heat-induced loss of wheat resistance was discussed.
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Yu, Kailiang; D'Odorico, Paolo; Carr, David E; Personius, Ashden; Collins, Scott L
2017-10-01
Plants with crassulacean acid metabolism (CAM) are increasing their abundance in drylands worldwide. The drivers and mechanisms underlying the increased dominance of CAM plants and CAM expression (i.e., nocturnal carboxylation) in facultative CAM plants, however, remain poorly understood. We investigated how nutrient and water availability affected competition between Mesembryanthemum crystallinum (a model facultative CAM species) and the invasive C 3 grass Bromus mollis that co-occur in California's coastal grasslands. Specifically we investigated the extent to which water stress, nutrients, and competition affect nocturnal carboxylation in M. crystallinum . High nutrient and low water conditions favored M. crystallinum over B. mollis , in contrast to high water conditions. While low water conditions induced nocturnal carboxylation in 9-week-old individuals of M. crystallinum , in these low water treatments, a 66% reduction in nutrient applied over the entire experiment did not further enhance nocturnal carboxylation. In high water conditions M. crystallinum both alone and in association with B. mollis did not perform nocturnal carboxylation, regardless of the nutrient levels. Thus, nocturnal carboxylation in M. crystallinum was restricted by strong competition with B. mollis in high water conditions. This study provides empirical evidence of the competitive advantage of facultative CAM plants over grasses in drought conditions and of the restricted ability of M. crystallinum to use their photosynthetic plasticity (i.e., ability to switch to CAM behavior) to compete with grasses in well-watered conditions. We suggest that a high drought tolerance could explain the increased dominance of facultative CAM plants in a future environment with increased drought and nitrogen deposition, while the potential of facultative CAM plants such as M. crystallinum to expand to wet environments is expected to be limited.
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da Silva, Meiriele; Pinho, Danilo B; Pereira, Olinto L; Fernandes, Fernando M; Barreto, Robert W
2016-01-01
A survey of foliicolous fungi associated with Dimorphandra wilsonii and Dimorphandra mollis (Fabaceae) was conducted in the state of Minas Gerais, Brazil. Dimorphandra wilsonii is a tree species native to the Brazilian Cerrado that is listed as critically endangered. Fungi strictly depending on this plant species may be on the verge of co-extinction. Here, results of the pioneering description of this mycobiota are provided to contribute to the neglected field of microfungi conservation. The mycobiota of D. mollis, which is a common species with a broad geographical distribution that co-occurs with D. wilsonii, was examined simultaneously to exclude fungal species occurring on both species from further consideration for conservation because microfungi associated with D. wilsonii should not be regarded as under threat of co-extinction. Fourteen ascomycete fungal species were collected, identified, described and illustrated namely: Byssogene wilsoniae sp. nov., Geastrumia polystigmatis, Janetia dimorphandra-mollis sp. nov., Janetia wilsoniae sp. nov., Johansonia chapadiensis, Microcalliopsis dipterygis, Phillipsiella atra, Piricauda paraguayensis, Pseudocercospora dimorphandrae sp. nov., Pseudocercosporella dimorphandrae sp. nov., Ramichloridiopsis wilsoniae sp. and gen. nov., Stomiopeltis suttoniae, Trichomatomyces byrsonimae and Vesiculohyphomyces cerradensis. Three fungi were exclusively found on D. wilsonii and were regarded as potentially threatened of extinction: B. wilsoniae, J. wilsoniae and R. wilsoniae.
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da Silva, Meiriele; Pinho, Danilo B.; Pereira, Olinto L.; Fernandes, Fernando M.; Barreto, Robert W.
2016-01-01
A survey of foliicolous fungi associated with Dimorphandra wilsonii and Dimorphandra mollis (Fabaceae) was conducted in the state of Minas Gerais, Brazil. Dimorphandra wilsonii is a tree species native to the Brazilian Cerrado that is listed as critically endangered. Fungi strictly depending on this plant species may be on the verge of co-extinction. Here, results of the pioneering description of this mycobiota are provided to contribute to the neglected field of microfungi conservation. The mycobiota of D. mollis, which is a common species with a broad geographical distribution that co-occurs with D. wilsonii, was examined simultaneously to exclude fungal species occurring on both species from further consideration for conservation because microfungi associated with D. wilsonii should not be regarded as under threat of co-extinction. Fourteen ascomycete fungal species were collected, identified, described and illustrated namely: Byssogene wilsoniae sp. nov., Geastrumia polystigmatis, Janetia dimorphandra-mollis sp. nov., Janetia wilsoniae sp. nov., Johansonia chapadiensis, Microcalliopsis dipterygis, Phillipsiella atra, Piricauda paraguayensis, Pseudocercospora dimorphandrae sp. nov., Pseudocercosporella dimorphandrae sp. nov., Ramichloridiopsis wilsoniae sp. and gen. nov., Stomiopeltis suttoniae, Trichomatomyces byrsonimae and Vesiculohyphomyces cerradensis. Three fungi were exclusively found on D. wilsonii and were regarded as potentially threatened of extinction: B. wilsoniae, J. wilsoniae and R. wilsoniae. PMID:26910334
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Alves, Clayton Q; Lima, Luciano S; David, Jorge M; Lima, Marcos V B; David, Juceni P; Lima, Fernanda W M; Pedroza, Kelly C M C; Queiroz, Luciano P
2013-07-01
Cratylia mollis Martius ex Benth. and Cenostigma macrophyllum Tul. (Leguminosae) are both endemic Brazilian plants and they are used by the natives as medicinal plants, and the leaves of C. mollis are also employed as forage for cattle during the dry season of region. Isolation of the compounds responsible for the acetylcholinesterase (AChE) inhibition from the CHCl3 active extract. Two peptidic compounds were isolated by chromatographic techniques from the CHCl3 extract of the leaves of C. mollis and C. macrophyllum. They were identified by spectrometric data analysis (MS and NMR) and they were subjected to AChE inhibition employing Ellman's test. The peptides were identified as N-benzoylphenylalaninoyl-phenlyalaninolacetate (aurentiamide acetate) (1) and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2). Both peptides 1 and 2 exhibit AChE inhibition, with IC50 values equal to 111.34 µM and 137.6 µM, respectively. Compound 1 (aurentiamide acetate) has rarely been isolated from the Leguminosae family, and N-benzoylphenylalaninyl-N-benzoylphenylalaninate (2) is a compound that has never previously been isolated from this family. Compound 1 is shown to be a potent inhibitor of AChE, with IC50 values similar to the physostigmine control (141.51 µM).
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Family Checkup: Positive Parenting Prevents Drug Abuse
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines Prescription Medicines Steroids (Anabolic) Synthetic Cannabinoids (K2/Spice) Synthetic Cathinones (Bath Salts) Tobacco/ ...
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Bader, Ammar; Martini, Francesca; Schinella, Guillermo R; Rios, Jose L; Prieto, Jose M
2015-01-01
Acanthus mollis (Acanthaceae), Achillea ligustica, Artemisia arborescens and Inula viscosa (Asteraceae) are used in Southern Italy against psoriasis and other skin diseases that occur with an imbalanced production of eicosanoids. We here assessed their in vitro effects upon 5-, 12-, 15-LOX and COX-1 enzymes as well as NFκB activation in intact cells as their possible therapeutic targets. All methanol crude extracts inhibited both 5-LOX and COX-1 activities under 200 µg/mL, without significant effects on the 12-LOX pathway or any relevant in vitro free radical scavenging activity. NFκB activation was prevented by all extracts but A. mollis. Interestingly, A. ligustica, A. arborescens and A. mollis increased the biosynthesis of 15(S)-HETE, an anti-inflammatory eicosanoid. A. ligustica (IC50 = 49.5 µg/mL) was superior to Silybum marianum (IC50 = 147.8 µg/mL), which we used as antipsoriatic herbal medicine of reference. Its n-hexane, dichloromethane and ethyl acetate fractions had also inhibitory effects on the LTB4 biosynthesis (IC50s = 9.6, 20.3 and 68 µg/mL, respectively) evidencing that the apolar extracts of A. ligustica are promising active herbal ingredients for future phytotherapeutical products targeting psoriasis. © 2014 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd. PMID:25278440
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Bader, Ammar; Martini, Francesca; Schinella, Guillermo R; Rios, Jose L; Prieto, Jose M
2015-01-01
Acanthus mollis (Acanthaceae), Achillea ligustica, Artemisia arborescens and Inula viscosa (Asteraceae) are used in Southern Italy against psoriasis and other skin diseases that occur with an imbalanced production of eicosanoids. We here assessed their in vitro effects upon 5-, 12-, 15-LOX and COX-1 enzymes as well as NFκB activation in intact cells as their possible therapeutic targets. All methanol crude extracts inhibited both 5-LOX and COX-1 activities under 200 µg/mL, without significant effects on the 12-LOX pathway or any relevant in vitro free radical scavenging activity. NFκB activation was prevented by all extracts but A. mollis. Interestingly, A. ligustica, A. arborescens and A. mollis increased the biosynthesis of 15(S)-HETE, an anti-inflammatory eicosanoid. A. ligustica (IC50 =49.5 µg/mL) was superior to Silybum marianum (IC50 =147.8 µg/mL), which we used as antipsoriatic herbal medicine of reference. Its n-hexane, dichloromethane and ethyl acetate fractions had also inhibitory effects on the LTB4 biosynthesis (IC50 s=9.6, 20.3 and 68 µg/mL, respectively) evidencing that the apolar extracts of A. ligustica are promising active herbal ingredients for future phytotherapeutical products targeting psoriasis. © 2014 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.
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NASA Astrophysics Data System (ADS)
Plath, Martin; Riesch, Rüdiger; Oranth, Alexandra; Dzienko, Justina; Karau, Nora; Schießl, Angela; Stadler, Stefan; Wigh, Adriana; Zimmer, Claudia; Arias-Rodriguez, Lenin; Schlupp, Ingo; Tobler, Michael
2010-08-01
Adaptation to ecologically heterogeneous environments can drive speciation. But what mechanisms maintain reproductive isolation among locally adapted populations? Using poeciliid fishes in a system with naturally occurring toxic hydrogen sulfide, we show that (a) fish from non-sulfidic sites ( Poecilia mexicana) show high mortality (95 %) after 24 h when exposed to the toxicant, while locally adapted fish from sulfidic sites ( Poecilia sulphuraria) experience low mortality (13 %) when transferred to non-sulfidic water. (b) Mate choice tests revealed that P. mexicana females exhibit a preference for conspecific males in non-sulfidic water, but not in sulfidic water, whereas P. sulphuraria females never showed a preference. Increased costs of mate choice in sulfidic, hypoxic water, and the lack of selection for reinforcement due to the low survival of P. mexicana may explain the absence of a preference in P. sulphuraria females. Taken together, our study may be the first to demonstrate independent—but complementary—effects of natural and sexual selection against immigrants maintaining differentiation between locally adapted fish populations.
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Plath, Martin; Riesch, Rüdiger; Oranth, Alexandra; Dzienko, Justina; Karau, Nora; Schiessl, Angela; Stadler, Stefan; Wigh, Adriana; Zimmer, Claudia; Arias-Rodriguez, Lenin; Schlupp, Ingo; Tobler, Michael
2010-08-01
Adaptation to ecologically heterogeneous environments can drive speciation. But what mechanisms maintain reproductive isolation among locally adapted populations? Using poeciliid fishes in a system with naturally occurring toxic hydrogen sulfide, we show that (a) fish from non-sulfidic sites (Poecilia mexicana) show high mortality (95 %) after 24 h when exposed to the toxicant, while locally adapted fish from sulfidic sites (Poecilia sulphuraria) experience low mortality (13 %) when transferred to non-sulfidic water. (b) Mate choice tests revealed that P. mexicana females exhibit a preference for conspecific males in non-sulfidic water, but not in sulfidic water, whereas P. sulphuraria females never showed a preference. Increased costs of mate choice in sulfidic, hypoxic water, and the lack of selection for reinforcement due to the low survival of P. mexicana may explain the absence of a preference in P. sulphuraria females. Taken together, our study may be the first to demonstrate independent-but complementary-effects of natural and sexual selection against immigrants maintaining differentiation between locally adapted fish populations.
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... made drugs often sold as marijuana substitutes (like Spice ). Although the law also bans chemically similar versions ... Ecstasy or Molly) Methamphetamine (Meth) Prescription Drugs Salvia Spice Tobacco, Nicotine, & E-Cigarettes Brain and Addiction Drug ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... are appropriately concerned about illicit drugs such as marijuana, cocaine, and LSD, they often ignore the dangers ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... Notes Articles Adolescent Cigarette, Alcohol Use Declines as Marijuana Use Rises ( February 2013 ) Program Helps Troubled Boys ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... were more likely to misuse opioid analgesics. Why Marijuana Displeases Basic Science , Published March 2018 This study ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... The Brain & the Actions of Cocaine, Opioids and Marijuana The first in a 5-part series, offers ...
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... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... in the past year. Middle Figure: Driving after marijuana use is more common than driving after alcohol ...
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Teens Mix Prescription Opioids with Other Substances
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... least one other substance in the past year. Marijuana and alcohol were the most common (58.5% ...
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Substance Use in Women and Men
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... Text Description of Infographic Figure 1: Differences in Marijuana Use Disorder Women: develop disorder more quickly 1 ...
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How Can Prescription Drug Addiction Be Treated?
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... Principles of Substance Abuse Prevention for Early Chil... Marijuana: Facts Parents Need to Know Marijuana: Facts for ...
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Richard Ames MacKenzie; Gregory L. Bruland
2012-01-01
Nekton communities were sampled from 38 Hawaiian coastal wetlands from 2007 to 2009 using lift nets, seines, and throw nets in an attempt to increase our understanding of the nekton assemblages that utilize these poorly studied ecosystems. Nekton were dominated by exotic species, primarily poeciliids (Gambusia affinis, Poecilia...
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Brief Intervention Helps Adolescents Curb Substance Use
... Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter Medicines ... Drugs Inhalants K2/Spice Kratom LSD (Acid) Marijuana MDMA (Ecstasy) Methamphetamine Opioids Other Drugs Over-the-Counter ...
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Treat Jail Detainees' Drug Abuse to Lower HIV Transmission
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... Illegal Drugs Inhalants K2/Spice Kratom LSD (Acid) Marijuana MDMA (Ecstasy) Methamphetamine Opioids Other Drugs Over-the- ...
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Expanded HIV Screening Projected to Decrease Spread of the Virus
... Alcohol Club Drugs Cocaine Fentanyl Hallucinogens Inhalants Heroin Marijuana MDMA (Ecstasy/Molly) Methamphetamine Opioids Over-the-Counter ... Illegal Drugs Inhalants K2/Spice Kratom LSD (Acid) Marijuana MDMA (Ecstasy) Methamphetamine Opioids Other Drugs Over-the- ...
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45 CFR 670.20 - Designation of native birds.
Code of Federal Regulations, 2012 CFR
2012-10-01
... chrysolophus. Rockhopper—Eudyptes crestatus. Petrel Antarctic—Thalassoica antarctica. Black-bellied Storm...—Pterodroma mollis. South-Georgia Diving—Pelecanoides georgicus. White-bellied Storm—Fregetta grallaria. White-chinned—Procellaria aequinoctialis. White-headed—Pterodroma lessoni. Wilson's Storm—Oceanites oceanicus...
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45 CFR 670.20 - Designation of native birds.
Code of Federal Regulations, 2014 CFR
2014-10-01
... chrysolophus. Rockhopper—Eudyptes crestatus. Petrel Antarctic—Thalassoica antarctica. Black-bellied Storm...—Pterodroma mollis. South-Georgia Diving—Pelecanoides georgicus. White-bellied Storm—Fregetta grallaria. White-chinned—Procellaria aequinoctialis. White-headed—Pterodroma lessoni. Wilson's Storm—Oceanites oceanicus...
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45 CFR 670.20 - Designation of native birds.
Code of Federal Regulations, 2013 CFR
2013-10-01
... chrysolophus. Rockhopper—Eudyptes crestatus. Petrel Antarctic—Thalassoica antarctica. Black-bellied Storm...—Pterodroma mollis. South-Georgia Diving—Pelecanoides georgicus. White-bellied Storm—Fregetta grallaria. White-chinned—Procellaria aequinoctialis. White-headed—Pterodroma lessoni. Wilson's Storm—Oceanites oceanicus...
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Biodiversity and ecosystem risks arising from using guppies to control mosquitoes
Rana W. El-Sabaawi; Therese C. Frauendorf; Piata S. Marques; Richard A. Mackenzie; Luisa R. Manna; Rosana Mazzoni; Dawn A. T. Phillip; Misha L. Warbanski; Eugenia Zandon
2016-01-01
Deploying mosquito predators such as the guppy (Poecilia reticulata) into bodies of water where mosquitoes breed is a common strategy for limiting the spread of disease-carrying mosquitoes. Here, we draw on studies from epidemiology, conservation, ecology and evolution to show that the evidence for the effectiveness of guppies in controlling...
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2001-03-07
RCN adviser in nursing practice Susan Scott visited Buckingham Palace last week to receive her MBE from the Queen. Ms Scott, who received the honour for services to nursing and the RCN, is pictured with her granddaughter Mollie.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-12-28
...: Mollie Lemon, Climate Protection Partnerships Division, Office of Atmospheric Programs, MC 6202J.... Partners are organizational entities that have volunteered to participate in either Partnership program.... Dated: December 21, 2011. Elizabeth Craig, Director, Climate Protection Partnerships Division. [FR Doc...
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Expansion of plants with Crassulacean Acid Metabolism under global environment change
NASA Astrophysics Data System (ADS)
Yu, K.; D'Odorico, P.; Collins, S. L.; Carr, D.
2016-12-01
The abundance of plants with Crassulacean Acid Metabolism (CAM) has increased in many drylands worldwide. This is hypothesized to occur because CAM plants store water, take up CO2 at night, exhibit photosynthetic plasticity, and have high water use efficiency. The increased dominance of CAM plants, however, also depends on their competitive relationship with other functional groups, an aspect of CAM plant sensitivity to global environmental change that has remained largely understudied. Here, we investigated the response of CAM plants and their competitive relationships with C3 and C4 plants under global environmental change. We focused on two pairs of CAM and non-CAM species, namely Cylindropuntia imbricata (a constitutive CAM species) and Bouteloua eriopoda (C4 grass), which co-occur in desert grasslands in northern Mexico, and invasive Mesembryanthemum crystallinum (a facultative CAM species) and Bromus mollis (a C3 invasive grass), which coexist in California's coastal grasslands. A set of growth chamber experiments under altered CO2 and water conditions show that C. imbricata outcompeted B. eriopoda under drought conditions, while in well-watered conditions B. eriopoda was a stronger competitor for soil water than C. imbricata. Under drought conditions a more positive response to CO2 enrichment by C. imbricata indirectly disfavored B. eriopoda, which suggests that interspecific competition can outweigh the favorable direct effect of CO2 enrichment on plant growth. A set of greenhouse experiments under water, N, and soil salinity manipulations showed that drought, N deposition, and/or increased soil salinity served as important drivers for success of M. crystallinum invasion, while B. mollis exerted strong competitive effects on M. crystallinum for light and soil nutrients in well-watered conditions. M. crystallinum switched from C3 photosynthesis to CAM photosynthesis as an adaptive strategy in response to moderate intensity of competition from B. mollis, in
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Women in the Military: Sexual Harassment
1993-04-01
male-dominated organizations, such as sports teams or fraternities.ŝ All services have reported that systems to track sexual harassment are in place...Link: The Feminization of America Military. Washington, D.C., Regnery Gateway Publishers, 1989. Moore, Molly. "Sexual Harassment: Attitudes of Male
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In the Flow of Media, Religion, and Culture: A Case Study with TVbyGIRLS
ERIC Educational Resources Information Center
Bischoff, Claire; Bullen, Rebecca Richards; Nemer, Molly; Quednau, Rachel
2011-01-01
This article introduces TVbyGIRLS, a nonprofit organization supporting girls in the development of critical thinking, digital literacy and storytelling, leadership, compassionate collaboration, and social justice engagement. Religious educator Claire Bischoff interviews Rebecca Richards Bullen, TVbyGIRLS mentor, and Molly Nemer and Rachel Quednau,…
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Dissolved Oxygen Data for Coos Estuary (Oregon)
The purpose of this product is the transmittal of dissolved oxygen data collected in the Coos Estuary, Oregon to Ms. Molly O'Neill (University of Oregon), for use in her studies on the factors influencing spatial and temporal patterns in dissolved oxygen in this estuary. These d...
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78 FR 24195 - Product Cancellation Order for Certain Pesticide Registrations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-24
... Insecticide, Fungicide, and Rodenticide Act (FIFRA). This cancellation order follows a December 19, 2012... effective December 31, 2016. FOR FURTHER INFORMATION CONTACT: Molly Clayton, Pesticide Re-Evaluation... registrants of the products in Tables 1. and 2. of this unit, in sequence by EPA company number. This number...
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USDA-ARS?s Scientific Manuscript database
The apple maggot fly, Rhagoletis pomonella, infests apple (Malus domestica) and hawthorn species (most notably the downy hawthorn, Crataegus mollis) in the eastern USA. Evidence suggests that the fly was introduced into the western USA sometime in the last 60 years. In addition to apple, R. pomonel...
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Characterization of indigenous rhizobia from caatinga
Pires e Teixeira, Fernanda Cíntia; Borges, Wardsson Lustrino; Xavier, Gustavo Ribeiro; Rumjanek, Norma Gouvêa
2010-01-01
The aim of this study was to characterize rhizobial isolates from Cratylia mollis Mart. ex Benth, Calliandra depauperata Benth. and Mimosa tenuiflora (Willd.) Poir. by means of rhizobial colonies morphology and restriction analysis of the 16S ribosomal gene (16S rDNA-ARDRA). Nodules were collected in the field and from plants cultivated in a greenhouse experiment using Caatinga soil samples. Sixty seven isolates were described by morphological analysis. Forty seven representative isolates were used for ARDRA analysis using seven restriction enzymes. We observed high diversity of both slow and fast-growing rhizobia that formed three morpho-physiological clusters. A few fast-growing isolates formed a group of strains of the Bradyrhizobium type; however, most of them diverged from the B. japonicum and B. elkanii species. Cratylia mollis nodule isolates were the most diverse, while all Mimosa tenuiflora isolates displayed fast growth with no pH change and were clustered into groups bearing 100% similarity, according to ARDRA results. PMID:24031482
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On the Limits of Cosmopolitanism and a "Curriculum of Refuge"
ERIC Educational Resources Information Center
Waghid, Y.
2010-01-01
In a recent essay entitled "Ex and the City": on cosmopolitanism, community and the "curriculum of refuge", Molly Quinn (2010) introduces her readers to a poetic exploration of cosmopolitanism and curriculum change. She begins and inconclusively ends her essay with poetic language and affirmation of cosmopolitan justice through…
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1998-06-01
Mike Lyden John Lantelme Andy Mackel Jesus Malgapo Carol Marcinek Greg Martin Michelle McAtee Molly McClellan Jerry McEnerney Laurie McKee...Paul McNeill Walt Melton Rich Mendez Mike Metts Jon Miller Ron Mosley Jim Naber Craig Nostrant NAVSUP USSNORMANDY(CG60) DDRE NORFOLK NPGS
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Data System Implementation: A Leader Navigates People Problems around Technology and Data Use
ERIC Educational Resources Information Center
Cho, Vincent; Jimerson, Jo Beth; Wayman, Jeffrey C.
2015-01-01
Computer data systems have become a lynchpin to supporting school data use. However, successfully implementing such systems is no easy task. In this case, readers explore the ways in which "technology problems" and "people problems" can be intertwined. The case follows Dr. Molly Winters as she encounters social and…
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USDA-ARS?s Scientific Manuscript database
The recent shift of Rhagoletis pomonella (Diptera: Tephritidae) from its native host downy hawthorn, Crataegus mollis, to introduced domesticated apple, Malus domestica, in the eastern U.S. is a model for sympatric host race formation. However, the fly is also present in the western U.S. where it ma...
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ERIC Educational Resources Information Center
Oder, Norman
2007-01-01
A funny thing happened while the District of Columbia Public Library (DCPL), already suffering from deteriorated facilities and systems, slogged through stasis (and three interim directors) after the 2003 departure of Director Molly Raphael. Mayor Anthony Williams presided over the city's economic turnaround--or, some charged, cozied up to…
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USDA-ARS?s Scientific Manuscript database
Heat-stress exerts profound impact on resistance of plants to parasites. In this research, we investigated the impact of an acute, transient heat-stress on the resistance of the wheat line 'Molly', which contains the resistance gene H13, to an avirulent Hessian fly [Mayetiola destructor (Say)] popu...
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Rangi Ruru Walk: Social and Spatial Connections through Hybrid Intermedial Practices
ERIC Educational Resources Information Center
Wood, Becca; Mullen, Molly
2016-01-01
In 2013 Becca Wood, Spatial Performance Practitioner, and Molly Mullen, Applied Theatre Practitioner, collaborated to create a short ambulatory performance with audio score for a group of drama educators attending a conference workshop on the possibilities of walking as performance. The performance was created remotely from the intended site:…
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Constructivists Online: Reimagining Progressive Practice. Occasional Paper Series 34
ERIC Educational Resources Information Center
Freidus, Helen, Ed.; Welsh Kruger, Mollie, Ed.; Goss, Steven, Ed.
2015-01-01
In this issue of the Occasional Paper Series, the authors reimagine progressive pedagogy within the framework of digital pedagogy and online practice. The issue begins with "Notes from the Special Issue Editors," Helen Freidus, Mollie Welsh Kruger & Steven Goss. In the first set of essays, "Inside the Online Classroom," the…
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USDA-ARS?s Scientific Manuscript database
The apple maggot fly, Rhagoletis pomonella Walsh (Diptera: Tephritidae), is a major pest of commercially grown domesticated apple (Malus domestica) in North America. The shift of the fly from its native host hawthorn (Crataegus mollis) to apple in the eastern U.S. is often cited as an example of inc...
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"These Is My Words" . . . Or Are They? Constructing Western Women's Lives in Two Contemporary Novels
ERIC Educational Resources Information Center
Adkison, Jennifer Dawes
2006-01-01
Literary critics and historians have long attempted to define what is authentic in western literature, praising those works that come closest to presenting a true picture of western life. When read through this lens, Molly Gloss' "The Jump Off Creek" and Nancy E. Turner's "These Is My Words" could be considered praiseworthy.…
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Liftoff of Gemini-Titan 3 mission
1965-03-23
S65-14150 (23 March 1965) --- Launch view of the Gemini-Titan 3 mission. The GT-3 liftoff was at 9:24 a.m. (EST) on March 23, 1965. The Gemini-3 spacecraft "Molly Brown" carried astronauts Virgil I. Grissom, command pilot, and John W. Young, pilot, on three orbits of Earth.
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Memorial Day 2007 - U.S. Department of Defense Official Website
Multimedia / Photos Videos Publications Bloggers DoD Websites Vietnam War Memorial. Photo by Navy Petty Officer 2nd Class Molly Burgess Presidential Proclamation - George W. Bush On Memorial Day, Americans their lives for our country and our freedom. Read More Slideshow: Memorial Day Parade See below
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Epilogue: The Child and the Environment
ERIC Educational Resources Information Center
O'Shaughnessy, Molly
2013-01-01
Molly wrote this article thirteen years ago. It is a fitting counterpart to the preface of this publicaton because it predicts the role of nature across the planes of education even before the Erdkinder was tested. The article combines contemporary environmentalists with Montessori's seminal insight into the developmental impact of nature on the…
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Factors mediating cheatgrass invasion of intact salt desert shrubland
Susan E. Meyer; Susan C. Garvin; Julie Beckstead
2001-01-01
Cheatgrass (Bromus tectorum) has recently displaced salt desert shrubland in many areas of the Great Basin. We studied the dynamics of cheatgrass invasion into an intact shadscale-gray molly community in Dugway Valley, Utah, by adding seeds and manipulating disturbance regime and resource availability. Shrub clipping or cryptobiotic crust trampling on large plots...
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Interview with Hilla Patell on the History of the Observation
ERIC Educational Resources Information Center
O'Shaughnessy, Molly; Patell, Hilla
2016-01-01
In this interview conducted at the NAMTA conference, "Observation: The Key to Unlocking the Child's Potential", Molly O'Shaughnessy discusses the history of observation with Hilla Patell. Patell shares stories of the people who were instrumental in creating a culture of observation as an ongoing discipline to be practiced. She goes on to…
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Stanley G. Kitchen; Stephen B. Monsen
2008-01-01
Two woodybased non-rhizomatous sub-shrub species of kochias are found in the western United States. The widely distributed native, gray molly, and its introduced and closely related counterpart (Blackwell and others 1978), forage kochia, are found in salt-desert, sagebrush, pinyon-juniper, and dry mountain brush communities (table 1). Erect to steeply ascending annual...
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75 FR 60126 - Performance Review Board Members
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-29
... Daulaire Beverly W. Davis Jeffrey S. Davis L'Tonya J. Davis Lori E. Davis Diann Dawson Molly P. Dawson.... Miller Tamara L. Miller George G. Mills Jr. Samuel P. Mitchell Madeline Mocko John W. Molina John T... William D. Saunders David W. Sayen James V. Scanlon Donald L. Schneider Lawrence N. Self James D. Seligman...
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A Modernizer Sets a New Course at the U. of North Carolina.
ERIC Educational Resources Information Center
Healy, Patrick
1999-01-01
Molly Corbett Broad, president of the University of North Carolina system and an economist by training, was brought in by the state treasurer to help convince the Teachers Insurance and Annuity Association-College Retirement Equities Fund (TIAA-CREF) to open a branch in North Carolina. The experience illustrates the kind of leadership Broad has…
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The Educational Situation in Utopia: Why "What Is," Is
ERIC Educational Resources Information Center
Seaman, Jayson; Quay, John
2015-01-01
In this response to Molly Ware's review of our 2013 book, "John Dewey and Education Outdoors," we extend her suggestion that complexity be regarded as an important, generative force in education reform. Drawing on Dewey's 1933 "Utopian Schools" speech, we discuss the "level deeper" that Dewey sought as he…
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Amundsen, C.C.
1985-01-01
Measured and inferred ecological characteristics and holocoenotic factors which affect the dynamics and manifestations of central Aleutian maritime tundra and beach-dune vegetational expressions of Adak and Amchitka Islands are discussed. The known vascular flora is enumerated and predominant taxa are grouped into communities and topoedaphic units. Stability of community composition and structure is elaborated and the absence of ecological succession demonstrated. Perturbations occasioned by human activities which impinge on these remote islands are detailed. The testing and monitoring of subsequent passive and managed recovery of stable vegetation on disturbed areas is described. Selection, preparation and utilization of transplants of Elymusmore » mollis Trin. is documented. Transplants of rhizomes of E. mollis are successful in the reestablishment of vegetative cover in disturbed habitats which are topoedaphically suitable for graminoid success. The responses of plant population stands to environmental processes and habitat insults are reported. The relatively limited but stable biota and the lethargic ecological response as defined by extant vegetational expressions provide field test potentials which mandate further basic and applied research.« less
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Negotiating the Curriculum: Surviving the First Year
ERIC Educational Resources Information Center
Poland, Molly
2013-01-01
Molly Poland is a first year English and Home Economics teacher who began her career in a small Far North Queensland town. In this article, she writes about her first year teaching and the last year of her degree and the challenges she faced as both teacher and student. Reading Boomer's "Negotiating the Curriculum" forced her to think a…
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Looking Ahead: Letters to the next President from Higher Education's Leaders
ERIC Educational Resources Information Center
Change: The Magazine of Higher Learning, 2008
2008-01-01
Given the importance of the upcoming Presidential election, not only to the nation as a whole but to higher education, this article presents a set of letters to the President-elect from a group of higher-education leaders: Secretary of Education Margaret Spellings; Molly Broad, president of the American Council on Education; Sir John Daniel,…
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Peace and Pedagogy. Peter Lang Primers
ERIC Educational Resources Information Center
Quinn, Molly
2014-01-01
What makes for peace as lived? What images of peace issue from examination of daily experience? What can be gleaned from reflection upon the topic for the meanings and makings of peace in our world? Considering that to work for peace, we must begin with ourselves and with our children, Molly Quinn addresses these questions through her own life and…
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Hey Matt! There's a "Reason" We Write Like Every Day!
ERIC Educational Resources Information Center
Toussant, Molly
2007-01-01
Fifth grade teacher Molly Toussant realized with chagrin that she habitually mouthed her precepts about teaching writing in the same rote way she had recited the Apostles' Creed in Sunday school, and that her students had no idea why they had to write "like every day." So she wrote this explication in which she shows, with many examples, how her…
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Assess, Coordinate, Execute: How to ACE an Executive Director Search. Issue Brief
ERIC Educational Resources Information Center
Mitchell, Mollie
2011-01-01
This issue brief presents a meaningful strategy for how charter school boards can hire top-notch, well-suited leaders for their schools. Written by Mollie Mitchell, founder and president of The K12 Search Group, this brief is a how-to guide for managing the process of bringing on a new charter school leader. As Ms. Mitchell notes, the only thing…
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da Silva, Luís Cláudio Nascimento; Alves, Neyla Maria Pereira; de Castro, Maria Carolina Accioly Brelaz; Pereira, Valéria Rêgo Alves; da Paz, Nathalia Varejão Nogueira; Coelho, Luana Cassandra Breitenbach Barroso; de Figueiredo, Regina Célia Bressan Queiroz; Correia, Maria Tereza dos Santos
2015-01-01
Peritoneal exudate cells (PECs) play important roles in host defense against Staphylococcus aureus and other pathogens. In this study we evaluated the potentials of native (pCramoll or Cramoll 1,4) and recombinant (rCramoll) lectins from seeds of Cratylia mollis as immunomodulatory tools on mice PECs infected and non-infected with S. aureus. Both lectins significantly enhanced nitric oxide, superoxide and cytokines (IL-1β, IL-6, IFN-γ and TNF-α). pCramoll and rCramoll downregulated the induction of TNF-α and IL-6 and upregulated the expression of IL-1β, IFN-γ in S. aureus infected PECs. Phagocytic activity of S. aureus was also enhanced in 27.1% and 22.47% by pCramoll and rCramoll, respectively. Our results showed that pCramoll induced stronger effects than rCramoll, which could be explained by the different hemagglutinating activities of C. mollis isolectins and nature fragmentation, although the biologic meaning should be studied in detail using in vivo models. Future works will be focused on the molecular mechanisms involved in these actions, using in vitro and in vivo models, to support the use of these lectins as biotechnological tool in immunological studies.
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Predator Avoidance in Extremophile Fish
Bierbach, David; Schulte, Matthias; Herrmann, Nina; Zimmer, Claudia; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Riesch, Rüdiger; Plath, Martin
2013-01-01
Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naïve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis. PMID:25371337
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Predator avoidance in extremophile fish.
Bierbach, David; Schulte, Matthias; Herrmann, Nina; Zimmer, Claudia; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Riesch, Rüdiger; Plath, Martin
2013-02-06
Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naïve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis.
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Tobler, M; Plath, M; Riesch, R; Schlupp, I; Grasse, A; Munimanda, G K; Setzer, C; Penn, D J; Moodley, Y
2014-05-01
The unprecedented polymorphism in the major histocompatibility complex (MHC) genes is thought to be maintained by balancing selection from parasites. However, do parasites also drive divergence at MHC loci between host populations, or do the effects of balancing selection maintain similarities among populations? We examined MHC variation in populations of the livebearing fish Poecilia mexicana and characterized their parasite communities. Poecilia mexicana populations in the Cueva del Azufre system are locally adapted to darkness and the presence of toxic hydrogen sulphide, representing highly divergent ecotypes or incipient species. Parasite communities differed significantly across populations, and populations with higher parasite loads had higher levels of diversity at class II MHC genes. However, despite different parasite communities, marked divergence in adaptive traits and in neutral genetic markers, we found MHC alleles to be remarkably similar among host populations. Our findings indicate that balancing selection from parasites maintains immunogenetic diversity of hosts, but this process does not promote MHC divergence in this system. On the contrary, we suggest that balancing selection on immunogenetic loci may outweigh divergent selection causing divergence, thereby hindering host divergence and speciation. Our findings support the hypothesis that balancing selection maintains MHC similarities among lineages during and after speciation (trans-species evolution). © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.
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1981-10-02
the factors controlling their distribution within the Leland Harris complex. Design of studies to examine critical areas in such a fashion will 5...Dewatering, channelizing, construction of cement-lined ditches, damming, and establishment of non -native Species of fishes or mollusks, reduce...population. The convict cichlid and mexican molly shared dominance in the fish fauna. Clearly, the non -native fish and the introduced snail, Melanoides
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Hanigan, M D; Rius, A G; Kolver, E S; Palliser, C C
2007-08-01
The Molly model predicts various aspects of digestion and metabolism in the cow, including nutrient partitioning between milk and body stores. It has been observed previously that the model underpredicts milk component yield responses to nutrition and consequently overpredicts body energy store responses. In Molly, mammary enzyme activity is represented as an aggregate of mammary cell numbers and activity per cell with minimal endocrine regulation. Work by others suggests that mammary cells can cycle between active and quiescent states in response to various stimuli. Simple models of milk production have demonstrated the utility of this representation when using the model to simulate variable milking and nutrient restriction. It was hypothesized that replacing the current representation of mammary cells and enzyme activity in Molly with a representation of active and quiescent cells and improving the representation of endocrine control of cell activity would improve predictions of milk component yield. The static representation of cell numbers was replaced with a representation of cell growth during gestation and early lactation periods and first-order cell death. Enzyme capacity for fat and protein synthesis was assumed to be proportional to cell numbers. Enzyme capacity for lactose synthesis was represented with the same equation form as for cell numbers. Data used for parameter estimation were collected as part of an extended lactation trial. Cows with North American or New Zealand genotypes were fed 0, 3, or 6 kg of concentrate dry matter daily during a 600-d lactation. The original model had root mean square prediction errors of 17.7, 22.3, and 19.8% for lactose, protein, and fat yield, respectively, as compared with values of 8.3, 9.4, and 11.7% for the revised model, respectively. The original model predicted body weight with an error of 19.7% vs. 5.7% for the revised model. Based on these observations, it was concluded that representing mammary synthetic
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Behavior favoring transmission in the viviparous monogenean Gyrodactylus turnbulli.
Cable, J; Scott, E C G; Tinsley, R C; Harris, P D
2002-02-01
Transmission by Gyrodactylus turnbulli occurs most frequently when its hosts (Poecilia reticulata) come into close contact. This study is the first description of a specific migratory behavior that facilitates transmission of a gyrodactylid from dead hosts. Recently-dead guppies typically float at the water's surface; G. turnbulli moves off these fish into the water film, hanging motionless with the haptor held by surface tension. Because guppies are surface feeders, detached parasites in the water film are more likely to contact a new host.
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2013-01-01
accountability and regulation, and civil- military relations and contractors’ effects on the military (Avant, 2005; Chesterman, 2010–2011; Cotton et al...standards aimed at regulating the private security industry, in particular, clearly mandate that these firms establish policies that pro- mote a safe...Gansler_Commission_Report_Final_071031.pdf Cotton , Sarah K., Ulrich Petersohn, Molly Dunigan, Q Burkhart, Megan Zander-Cotugno, Edward O’Connell, and Michael Webber, Hired Guns: Views
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinez, Jessica S.; Schlenoff, Joseph B.; Keller, Thomas C.S., E-mail: tkeller@bio.fsu.edu
Polyelectrolyte multilayers (PEMUs) are tunable thin films that could serve as coatings for biomedical implants. PEMUs built layer by layer with the polyanion poly(acrylic acid) (PAA) modified with a photosensitive 4-(2-hydroxyethoxy) benzophenone (PAABp) group and the polycation poly(allylamine hydrochloride) (PAH) are mechanically tunable by UV irradiation, which forms covalent bonds between the layers and increases PEMU stiffness. PAH-terminated PEMUs (PAH-PEMUs) that were uncrosslinked, UV-crosslinked to a uniform stiffness, or UV-crosslinked with an edge mask or through a neutral density optical gradient filter to form continuous compliance gradients were used to investigate how differences in PEMU stiffness affect the adhesion andmore » migration of epithelial cell sheets from scales of the fish Poecilia sphenops (Black Molly) and Carassius auratus (Comet Goldfish). During the progressive collective cell migration, the edge cells (also known as ‘leader’ cells) in the sheets on softer uncrosslinked PEMUs and less crosslinked regions of the gradient formed more actin filaments and vinculin-containing adherens junctions and focal adhesions than formed in the sheet cells on stiffer PEMUs or glass. During sheet migration, the ratio of edge cell to internal cell (also known as ‘follower’ cells) motilities were greater on the softer PEMUs than on the stiffer PEMUs or glass, causing tension to develop across the sheet and periods of retraction, during which the edge cells lost adhesion to the substrate and regions of the sheet retracted toward the more adherent internal cell region. These retraction events were inhibited by the myosin II inhibitor Blebbistatin, which reduced the motility velocity ratios to those for sheets on the stiffer PEMUs. Blebbistatin also caused disassembly of actin filaments, reorganization of focal adhesions, increased cell spreading at the leading edge, as well as loss of edge cell-cell connections in epithelial cell sheets on all
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Villalba-Villalba, Ana Gloria; Ramírez-Suárez, Juan Carlos; Pacheco-Aguilar, Ramón; Valenzuela-Soto, Elisa Miriam; Lugo-Sánchez, María Elena; Figueroa-Soto, Ciria Guadalupe
2013-04-01
Pterygoplichthys disjunctivus viscera chymotrypsin was purified by fractionation with ammonium sulfate (30-70 % saturation), gel filtration, affinity, and ion exchange chromatography. Chymotrypsin molecular weight was approximately 29 kDa according to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), shown a single band in zymogram. Electrofocusing study suggested being an anionic enzyme (pI ≈ 3.9), exhibiting maximal activity at pH 9 and 50 °C, using Suc-Ala-Ala-Pro-Phe-p-nitroanilide (SAAPNA) as substrate. Enzyme was effectively inhibited by phenyl methyl sulfonyl fluoride (PMSF) (99 %), and N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) (94 %). Enzyme activity was affected by the following ions in decreasing order: Hg(2+), Fe(2+), Cu(2+), Li(1+), Mg(2+), K(1+), Mn(2+), while Ca(2+) had no effect. Chymotrypsin activity decreased continuously as NaCl concentration increased (from 0 to 30 %). K m and V max values were 0.72 ± 1.4 mM and 1.15 ± 0.06 μmol/min/mg of protein, respectively (SAAPNA as substrate). Results suggest the enzyme has a potential application where low processing temperatures are needed, such as in fish sauce production.
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The imperiled fish fauna in the Nicaragua Canal zone
Torres‐Dowdall, Julián; Meyer, Axel
2016-01-01
Abstract Large‐scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far‐reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly. PMID:27253906
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2016-11-01
collegiate soccer players . KB snatches were performed 3 days per week for 20 minutes with 15-second work-to-rest intervals, while the control group...10] used KB weights that were 18% of total body mass and reported a 6% improvement in aerobic capacity in women’s collegiate soccer players who...Force Personnel: A Pilot Study Molly Wade, MS; Reginald O’Hara, PhD; Lydia Caldwell, MS; Jason Ordway, MS; Darryn Bryant, MS
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Climate alters response of an endemic island plant to removal of invasive herbivores.
McEachern, A Kathryn; Thomson, Diane M; Chess, Katherine A
2009-09-01
Islands experience higher rates of species extinction than mainland ecosystems, with biological invasions among the leading causes; they also serve as important model systems for testing ideas in basic and applied ecology. Invasive removal programs on islands are conservation efforts that can also be viewed as powerful manipulative experiments, but few data are available to evaluate their effects. We collected demographic and herbivore damage data for Castilleja mollis Pennell, an endangered plant endemic to Santa Rosa Island, California, over a 12-year period before, during, and after the implementation of control for introduced cattle, deer, and elk. We used these long-term data to explore mechanisms underlying herbivore effects, assess the results of herbivore reduction at the scales of both individual plants and populations, and determine how temporal variability in herbivory and plant demography influenced responses to herbivore removals. For individual plants, herbivore effects mediated by disturbance were greater than those of grazing. Deer and elk scraping of the ground substantially increased plant mortality and dormancy and reduced flowering and growth. Stem damage from browsing did not affect survivorship but significantly reduced plant growth and flower production. Herbivore control successfully lowered damage rates, which declined steeply between 1997 and 2000 and have remained relatively low. Castilleja mollis abundances rose sharply after 1997, suggesting a positive effect of herbivore control, but then began to decline steadily again after 2003. The recent decline appears to be driven by higher mean growing season temperatures; interestingly, not only reductions in scraping damage but a period of cooler conditions were significant in explaining increases in C. mollis populations between 1997 and 2002. Our results demonstrate strong effects of introduced herbivores on both plant demography and population dynamics and show that climate
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Climate alters response of an endemic island plant to removal of invasive herbivores
Kathryn, Mceachern A.; Thomson, D.M.; Chess, K.A.
2009-01-01
Islands experience higher rates of species extinction than mainland ecosystems, with biological invasions among the leading causes; they also serve as important model systems for testing ideas in basic and applied ecology. Invasive removal programs on islands are conservation efforts that can also be viewed as powerful manipulative experiments, but few data are available to evaluate their effects. We collected demographic and herbivore damage data for Castilleja mollis Pennell, an endangered plant endemic to Santa Rosa Island, California, over a 12-year period before, during, and after the implementation of control for introduced cattle, deer, and elk. We used these long-term data to explore mechanisms underlying herbivore effects, assess the results of herbivore reduction at the scales of both individual plants and populations, and determine how temporal variability in herbivory and plant demography influenced responses to herbivore removals. For individual plants, herbivore effects mediated by disturbance were greater than those of grazing. Deer and elk scraping of the ground substantially increased plant mortality and dormancy and reduced flowering and growth. Stem damage from browsing did not affect survivorship but significantly reduced plant growth and flower production. Herbivore control successfully lowered damage rates, which declined steeply between 1997 and 2000 and have remained relatively low. Castilleja mollis abundances rose sharply after 1997, suggesting a positive effect of herbivore control, but then began to decline steadily again after 2003. The recent decline appears to be driven by higher mean growing season temperatures; interestingly, not only reductions in scraping damage but a period of cooler conditions were significant in explaining increases in C. mollis populations between 1997 and 2002. Our results demonstrate strong effects of introduced herbivores on both plant demography and population dynamics and show that climate
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The imperiled fish fauna in the Nicaragua Canal zone.
Härer, Andreas; Torres-Dowdall, Julián; Meyer, Axel
2017-02-01
Large-scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far-reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.
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Mullin, Katherine
2008-01-01
This article investigates James Joyce's fascination with a wide variety of medical texts, sexual folklores, religious beliefs, and persistent superstitions about menstruation. That fascination finds its way into Ulysses, which draws upon a number of intertexts to inform a curiosity about the female body most strikingly articulated by Bloom, Molly, and Gerty MacDowell. These intertexts are not simply imported into the novel but are dismantled and interrogated, as Joyce exposes, rather than endorses, clichés of essential femininity.
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The early-stage diagnosis of albinic embryos by applying optical coherence tomography
NASA Astrophysics Data System (ADS)
Yang, Bor-Wen; Wang, Shih-Yuan; Wang, Yu-Yen; Cai, Jyun-Jhang; Chang, Chung-Hao
2013-09-01
Albinism is a kind of congenital disease of abnormal metabolism. Poecilia reticulata (guppy fish) is chosen as the model to study the development of albinic embryos as it is albinic, ovoviviparous and with short life period. This study proposed an imaging method for penetrative embryo investigation using optical coherence tomography. By imaging through guppy mother’s reproduction purse, we found the embryo’s eyes were the early-developed albinism features. As human’s ocular albinism typically appear at about four weeks old, it is the time to determine if an embryo will grow into an albino.
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Muganga, Raymond; Angenot, Luc; Tits, Monique; Frédérich, Michel
2014-04-01
In our previous study, we reported the interesting in vitro antiplasmodial activity of some Rwandan plant extracts. This gave rise to the need for these extracts to also be evaluated in vivo and to identify the compounds responsible for their antiplasmodial activity. The aim of our study was, on the one hand, to evaluate the antiplasmodial activity in vivo and the safety of the selected Rwandan medicinal plants used in the treatment of malaria, with the objective of promoting the development of improved traditional medicines and, on the other hand, to identify the active ingredients in the plants. Plant extracts were selected according to their selectivity index. The in vivo antiplasmodial activity of aqueous, methanolic, and dichloromethane extracts was then evaluated using the classical 4-day suppressive test on Plasmodium berghei infected mice. The activity of the plant extracts was estimated by measuring the percentage of parasitemia reduction, and the survival of the experimental animals was recorded. A bioguided fractionation was performed for the most promising plants, in terms of antiplasmodial activity, in order to isolate active compounds identified by means of spectroscopic and spectrometric methods. The highest level of antiplasmodial activity was observed with the methanolic extract of Fuerstia africana (> 70 %) on days 4 and 7 post-treatment after intraperitoneal injection and on day 7 using oral administration. After oral administration, the level of parasitemia reduction observed on day 4 post-infection was 44 % and 37 % with the aqueous extract of Terminalia mollis and Zanthoxylum chalybeum, respectively. However, the Z. chalybeum extract presented a high level of toxicity after intraperitoneal injection, with no animals surviving on day 1 post-treatment. F. africana, on the other hand, was safer with 40 % mouse survival on day 20 post-treatment. Ferruginol is already known as the active ingredient in F. Africana, and ellagic acid (IC50
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Lower lethal temperatures for nonnative freshwater fishes in Everglades National Park, Florida
Schofield, Pam; Kline, Jeffrey L.
2018-01-01
Temperature is an important factor that shapes biogeography and species composition. In southern Florida, the tolerance of nonnative freshwater fishes to low temperatures is a critical factor in delineating their geographic spread. In this study, we provide empirical information on experimentally derived low-temperature tolerance limits of Banded Cichlid Heros severus and Spotfin Spiny Eel Macrognathus siamensis, two nonnative Everglades fishes that were lacking data, and African Jewelfish Hemichromis letourneuxi and Mayan Cichlid Cichlasoma urophthalmus, species for which previous results were derived from studies with small sample sizes. We also provide a literature review summarizing the current state of knowledge of low-temperature tolerances for all 17 nonnative freshwater fishes that have been found in Everglades National Park. Mean lower lethal temperature tolerances ranged from 4°C (Orinoco Sailfin Catfish Pterygoplichthys multiradiatus) to 16.1°C (Butterfly Peacock Bass Cichla ocellaris). These low-temperature limits may inform the understanding of the ecological role or influence of nonnative fishes and may lead to potential management opportunities and applications.
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The validity of three tests of temperament in guppies (Poecilia reticulata).
Burns, James G
2008-11-01
Differences in temperament (consistent differences among individuals in behavior) can have important effects on fitness-related activities such as dispersal and competition. However, evolutionary ecologists have put limited effort into validating their tests of temperament. This article attempts to validate three standard tests of temperament in guppies: the open-field test, emergence test, and novel-object test. Through multiple reliability trials, and comparison of results between different types of test, this study establishes the confidence that can be placed in these temperament tests. The open-field test is shown to be a good test of boldness and exploratory behavior; the open-field test was reliable when tested in multiple ways. There were problems with the emergence test and novel-object test, which leads one to conclude that the protocols used in this study should not be considered valid tests for this species. (PsycINFO Database Record (c) 2008 APA, all rights reserved).
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GEMINI-TITAN (GT)-3 - EARTH- SKY VIEW
1965-03-23
S65-18740 (23 March 1965) --- Astronaut John W. Young took this picture during the second orbit of the Gemini-Titan 3 three-orbit mission as the spacecraft "Molly Brown" passed over Northern Mexico at an altitude of 90 miles. The light-brown circular area at the lower right is the Sonoran Desert. The lower portion of the picture is Mexico, and the upper part is California. Young used a hand-held modified 70mm Hasselblad camera with color film. The lens setting was 250th of a second at f/11.
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U. S. Pacific Fleet. Central Pacific Force. Operation Plan Number Cen 1-43
1943-10-25
50.2 TG 50.2 CTG 50.3 TG 50.3 CTG 50.4 TG 50.4 CTG 50.5 TG 50.5 CTG 50.6 TG 50.6 Coronet Caucus Anz&e Mqrocco Rugby Tomahawk Anzac • Bluejacket...Ginger snap Maxwell Anzac Rugby Molly Potluck Garfield Rustic 1 Rustic 2 Rustic 3 Rustic 4 Rustic 5 Trigger 1 Trigger 2 Trigger 3 Trigger 4 Trigger 5...Yonkers Scranton LaCrosce Journal De Soto Hardtack I-iiiriot Tripod Stockade Einstein SAGINAW Chicago Glencoe Romeo Morocco GeroniiAo San Jiateo Rugby
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Tobler, Michael
2009-01-01
Immigrant inviability, where individuals from foreign, ecologically divergent habitats are less likely to survive, can restrict gene flow among diverging populations and result in speciation. I investigated whether a predatory aquatic insect (Belostoma sp.) selects against migrants between cave and surface populations of a fish (Poecilia mexicana). Cavefish were more susceptible to attacks in the light, whereas surface fish were more susceptible in darkness. Environmentally dependent susceptibility to attacks may thus contribute to genetic and phenotypic differentiation between the populations. This study highlights how predation—in this case in conjunction with differences in other environmental factors—can be an important driver in speciation. PMID:19443506
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Survival in an extreme habitat: the roles of behaviour and energy limitation
NASA Astrophysics Data System (ADS)
Plath, Martin; Tobler, Michael; Riesch, Rüdiger; García de León, Francisco J.; Giere, Olav; Schlupp, Ingo
2007-12-01
Extreme habitats challenge animals with highly adverse conditions, like extreme temperatures or toxic substances. In this paper, we report of a fish ( Poecilia mexicana) inhabiting a limestone cave in Mexico. Several springs inside the cave are rich in toxic H2S. We demonstrate that a behavioural adaptation, aquatic surface respiration (ASR), allows for the survival of P. mexicana in this extreme, sulphidic habitat. Without the possibility to perform ASR, the survival rate of P. mexicana was low even at comparatively low H2S concentrations. Furthermore, we show that food limitation affects the survival of P. mexicana pointing to energetically costly physiological adaptations to detoxify H2S.
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NASA Astrophysics Data System (ADS)
Mullabaev, Albert; Tkacheva, Olga; Shishkin, Vladimir; Kovrov, Vadim; Zaikov, Yuriy; Sukhanov, Leonid; Mochalov, Yuriy
2018-03-01
Crystallization temperatures (liquidus and solidus) in the LiCl-Li2O and (LiCl-KCl)-Li2O systems with the KCl content of 10 and 20 mol.% were obtained with independent methods of thermal analysis using cooling curves, isothermal saturation, and differential scanning calorimetry. The linear sweep voltammetry was applied to control the time of the equilibrium establishment in the molten system after the Li2O addition, which depended on the composition of the base melt and the concentration of Li2O. The fragments of the binary LiCl-Li2O and quazi-binary [LiCl-KCl(10 mol.%)]-Li2O and [LiCl-KCl(20 mol.%)]-Li2O phase diagrams in the Li2O concentration range from 0 to 12 mol.% were obtained. The KCl presence in the LiCl-KCl-Li2O molten mixture in the amount of 10 and 20 mol.% reduces the liquidus temperature by 30 and 80°, respectively, but the region of the homogeneous molten state of the system is considerably narrowed, which complicates its practical application. The Li2O solubility in the molten LiCl, LiCl-KCl(10 mol.%) and LiCl-KCl(20 mol.%) decreases with increasing the KCl content and is equal to 11.5, 7.7 and 3.9 mol.% at 650°С, respectively. The LiCl-KCl melt with 10 mol.% KCl can be recommended for practical use as a medium for the SNF pyro-chemical reprocessing at temperature below 700 °C.
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Potential effects of Cramoll 1,4 lectin on murine Schistosomiasis mansoni.
Melo, Cristiane Moutinho Lagos de; de Lima, Amanda Lucena Rosendo; Beltrão, Eduardo Isidoro Carneiro; Cavalcanti, Carmelita C Bezerra; de Melo-Júnior, Mário Ribeiro; Montenegro, Silvia Maria L; Coelho, Luana Cassandra B Barroso; Correia, Maria Tereza dos Santos; Carneiro-Leão, Ana Maria dos Anjos
2011-05-01
Cratylia mollis is a natural forage plant from the Northeast of Brazil. C. mollis seed lectin (Cramoll) containing molecular forms 1 and 4 (Cramoll 1,4) has shown anti-inflammatory and wound-healing activities. This work analyzed the effect of Cramoll 1,4 on experimental schistosomiasis in mice. Experimental groups (n=15/group) were composed of female albino Swiss mice, which were subcutaneously and caudally infected with Schistosoma mansoni (BH strain, 100 cercariae/mouse) and were treated with an intraperitoneal dose after infection as follows: (1) Cramoll 1,4 (50 mg kg(-1) single dose - after 40 days of infection), (2) Cramoll 1,4 (7 mg kg(-1) daily dose - for 7 days after infection) and control (untreated mice). Mice were sacrificed 8 weeks after infection and adult worms were recovered from the portal-hepatic system. Livers were fixed in 10% (v/v) formaldehyde/0.15M NaCl and tissue sections were processed for haematoxilin and Masson's trichrome stainings. Mice infected subcutaneously harboured no or very few worms and hence the effect of Cramoll 1,4 could not be assessed. Results (P≤0.05) were obtained with Cramoll 1,4 using the two treatments, with reduction of: egg excretion (79 and 80%), adult worm recovery (71 and 79%) and liver granulomas (40 and 73.5%) in relation to control. This study showed the potential anti-helminthic activity of Cramoll 1,4 when tested against Schistosomiasis mansoni infection in mice. Copyright © 2011 Elsevier B.V. All rights reserved.
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An Index of Biotic Integrity for shallow streams of the Hondo River basin, Yucatan Peninsula.
Schmitter-Soto, Juan J; Ruiz-Cauich, Lissie E; Herrera, Roberto L; González-Solís, David
2011-01-15
An Index of Biotic Integrity (IBI) is proposed, based on the fish communities and populations in streams of the Hondo River basin, Mexico-Belize. Freshwater environments in this area are threatened by exotic fishes, eutrophication, and pesticide pollution, among other problems. This IBI should allow to identify the most vulnerable sites and eventually guide rehabilitation efforts. Data on composition, structure, and function of fish communities were evaluated. Twenty-three sites in the Mexican part of the basin were explored; a stratified sample of 13 sites was used to design the IBI, and the rest were used to test and refine the index. Thirty-four candidate indicator metrics were scanned for their correlation with an index of water and habitat quality (IWHQ), as well as for the possible influence of stream width and altitude or distance to the Hondo River mainstem. Twelve variables were selected to constitute the IBI: relative abundances of Astyanax aeneus, 'Cichlasoma' urophthalmus, Poecilia mexicana, Poecilia sp. (a new species, probably endemic to the upper Hondo River basin), Xiphophorus hellerii, and X. maculatus; relative abundances of bentholimnetic, herbivore, and sensitive species; percentage of native and tolerant species; and Pielou's evenness index. Most of the sites have a low-medium quality and integrity, showing impact due to partial channelization or to suboptimal water quality, reflected in scarcity or absence of sensitive species, frequent excess of tolerant species, occasional presence of exotics, dominance of herbivores (perhaps due to proliferation of filamentous algae), or dominance of the opportunistic species P. mexicana. The streams with better water and habitat quality are those farthest away from the river mainstem, probably because of lower human population and economical production. Copyright © 2010 Elsevier B.V. All rights reserved.
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GEMINI-TITAN (GT)-3 - EARTH-SKY VIEWS - CA
1965-03-23
S65-18741 (23 March 1965) --- Astronaut John W. Young took this picture during the Gemini-Titan 3 three-orbit mission as the spacecraft "Molly Brown" passed over Northern Mexico. The large light-brown area is the Sonoran Desert. The Colorado River runs from upper right to lower left. The lower portion of the picture is Mexico, the upper left is California, and the upper right is Arizona. The altitude of the spacecraft was 90 miles. Young used a hand-held modified 70mm Hasselblad camera with color film. The lens setting was 250th of a second at f/11.
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Saffran, Lise
2017-01-07
Research linking reading literary fiction to empathy supports health humanities programs in which reflective writing accompanies close readings of texts, both to explore principles of storytelling (narrative arc and concrete language) and to promote an examination of biases in care. Little attention has been paid to the possible contribution of guided fiction-writing in health humanities curricula toward enhancing cultural competence among health professionals, both clinical and community-based. Through an analysis of the short story "Pie Dance" by Molly Giles, juxtaposed with descriptions of specific writing exercises, this paper explains how the demands of writing fiction promote cultural competency.
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Devigili, Alessandro; Evans, Jonathan P; Di Nisio, Andrea; Pilastro, Andrea
2015-09-15
In many species, females mate with multiple partners, meaning that sexual selection on male traits operates across a spectrum that encompasses the competition for mates (that is, before mating) and fertilizations (after mating). Despite being inextricably linked, pre- and postcopulatory sexual selection are typically studied independently, and we know almost nothing about how sexual selection operates across this divide. Here we bridge this knowledge gap using the livebearing fish Poecilia reticulata. We show that both selective episodes, as well as their covariance, explain a significant component of variance in male reproductive fitness. Moreover, linear and nonlinear selection simultaneously act on pre- and postcopulatory traits, and interact to generate multiple phenotypes with similar fitness.
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Mehta, Bhairav B; Auger, Daniel A; Gonzalez, Jorge A; Workman, Virginia; Chen, Xiao; Chow, Kelvin; Stump, Claire J; Mazimba, Sula; Kennedy, Jamie L W; Gay, Elizabeth; Salerno, Michael; Kramer, Christopher M; Epstein, Frederick H; Bilchick, Kenneth C
2015-12-21
Assessment of diffuse right ventricular (RV) fibrosis is of particular interest in pulmonary hypertension (PH) and heart failure (HF). Current cardiovascular magnetic resonance (CMR) T1 mapping techniques such as Modified Look-Locker inversion recovery (MOLLI) imaging have limited resolution, but accelerated and navigator-gated Look-Locker imaging for cardiac T1 estimation (ANGIE) is a novel CMR sequence with spatial resolution suitable for T1 mapping of the RV. We tested the hypothesis that patients with PH would have significantly more RV fibrosis detected with MRI ANGIE compared with normal volunteers and patients having HF with reduced (LV) ejection fraction (HFrEF) without co-existing PH, independent of RV dilitation and dysfunction. Patients with World Health Organization group 1 or group 4 PH, patients with HFrEF without PH, and normal volunteers were recruited to undergo contrast-enhanced CMR. RV and LV extracellular volume fractions (RV-ECV and LV-ECV) were determined using pre-contrast and post-contrast T1 mapping using ANGIE (RV and LV) and MOLLI (LV only). Thirty-two participants (53.1% female, median age 52 years, IQR 26-65 years) were enrolled, including n = 12 with PH, n = 10 having HFrEF without co-existing PH, and n = 10 normal volunteers. ANGIE ECV imaging was of high quality, and ANGIE measurements of LV-ECV were highly correlated with those of MOLLI (r = 0.91; p < 0.001). The RV-ECV in PH patients was 27.2% greater than the RV-ECV in normal volunteers (0.341 v. 0.268; p < 0.0001) and 18.9% greater than the RV-ECV in HFrEF patients without PH (0.341 v. 0.287; p < 0.0001). RV-ECV was greater than LV-ECV in PH (RV-LV difference = 0.04), but RV-ECV was nearly equivalent to LV-ECV in normal volunteers (RV-LV difference = 0.002) (p < 0.0001 for RV-LV difference in PH versus normal volunteers). RV-ECV was linearly associated with both increasing RVEDVI (p = 0.049) and decreasing RVEF (p = 0.04) in a
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Besser, John M.; Brumbaugh, William G.; Papoulias, Diana M.; Ivey, Chris D.; Kunz, James L.; Annis, Mandy; Ingersoll, Christopher G.
2012-01-01
that risks of Se toxicity are low in pupfish habitats. The dietary threshold was about twice as high as the greatest mean Se concentrations reported in midge larvae from seven sites in the Imperial Valley. Whole-body thresholds were greater than mean whole-body Se concentrations reported for field-collected pupfish from three sites and for the sailfin molly (Poecilia latipinna), a potential bioaccumulation surrogate for pupfish, from seven sites.Reduced egg production, although highly variable, was the most sensitive response of pupfish to Se exposure. Toxic effects on egg production (reductions of 24–51 percent relative to controls) occurred in the four highest Se treatments, corresponding to reproductive toxicity thresholds of 7.3 μg/g for Se in diet, 3.4 μg/g in pupfish (whole body), and 4.4 μg/g in pupfish eggs. These thresholds are substantially lower than published Se toxicity values for reproductive effects in other freshwater fish (for example, 17–24 μg/g in eggs). Reduced egg production has not been reported as a sensitive endpoint in Se toxicity studies, although abnormal ovarian development has been reported in Se-exposed fish, and reduced egg production has been reported as a sensitive response of other Cyprinodon pupfish to other environmental stressors.Selenium concentrations in tissues of pupfish, mollies, and diet items from Imperial Valley sites frequently exceeded concentrations associated with reduced pupfish egg production in the laboratory study. Reduced egg production may limit the ability of pupfish populations to persist and recover in Se-contaminated habitats in the Imperial Valley and elsewhere in their limited range. However, these apparent risks of Se toxicity are not supported by recent surveys of desert pupfish populations in the Imperial Valley. These surveys indicated that desert pupfish made up a small, but variable, component of fish communities in Imperial Valley habitats, including sites with increased levels of Se exposure
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Effect of Fodder Tree Species with Condensed Tannin Contents on In vitro Methane Production
Vázquez, Ernestina Gutiérrez; Medina, Leonardo Hernández; Benavides, Liliana Márquez; Caratachea, Aureliano Juárez; Razo, Guillermo Salas; Burgos, Armin Javier Ayala; Rodríguez, Ruy Ortiz
2016-01-01
The objective was to evaluate the effect of fodder tree species (FTS) with condensed tannin contents: Cordia elaeagnoides, Platymiscium lasiocarpum, Vitex mollis, and Haematoxylon brasiletto, on in vitro methane (CH4) production at 24 h post incubation. The analysis was performed using the in vitro gas production technique, with three levels of inclusion/species: 600, 800, and 1,000 mg and with 4 replicates/species/level of inclusion. The substrate was incubated at 39°C, and the gas and CH4 production were recorded at 4, 8, 12, and 24 h post incubation. The data collected was analyzed through Pearson correlation, polinomial regression and fixed effects models. There were negative correlations between FTS-total gas volume (r = −0.40; p<0.001); FTS-volume of CH4 produced (r = −0.40; p<0.001) and between the inclusion level-volume of CH4 produced (r = −0.20; p<0.001). As well as a positive correlation between hours post incubation-total gas volume (r = 0.42; p<0.001) and between hours post incubation-volume of CH4 produced (r = 0.48; p<0.001). The FTS: C. elaeagnoides, V. mollis, and H. brasiletto have potential, in the three inclusion levels analyzed, to reduce CH4 emission on in vitro trials (>32.7%), taking into account the total CH4 production at 24 h of the forage used as reference (Avena sativa). It’s suggested that C. elaeagnoides-according to its crude protein, neutral detergent fiber, and condensed tannins content- is the best alternative within the FTS analyzed, for feeding ruminants and for the control of CH4 emissions during the dry season. PMID:26732330
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Complex Consequences of Herbivory and Interplant Cues in Three Annual Plants
Pearse, Ian S.; Porensky, Lauren M.; Yang, Louie H.; Stanton, Maureen L.; Karban, Richard; Bhattacharyya, Lisa; Cox, Rosa; Dove, Karin; Higgins, August; Kamoroff, Corrina; Kirk, Travis; Knight, Christopher; Koch, Rebecca; Parker, Corwin; Rollins, Hilary; Tanner, Kelsey
2012-01-01
Information exchange (or signaling) between plants following herbivore damage has recently been shown to affect plant responses to herbivory in relatively simple natural systems. In a large, manipulative field study using three annual plant species (Achyrachaena mollis, Lupinus nanus, and Sinapis arvensis), we tested whether experimental damage to a neighboring conspecific affected a plant's lifetime fitness and interactions with herbivores. By manipulating relatedness between plants, we assessed whether genetic relatedness of neighboring individuals influenced the outcome of having a damaged neighbor. Additionally, in laboratory feeding assays, we assessed whether damage to a neighboring plant specifically affected palatability to a generalist herbivore and, for S. arvensis, a specialist herbivore. Our study suggested a high level of contingency in the outcomes of plant signaling. For example, in the field, damaging a neighbor resulted in greater herbivory to A. mollis, but only when the damaged neighbor was a close relative. Similarly, in laboratory trials, the palatability of S. arvensis to a generalist herbivore increased after the plant was exposed to a damaged neighbor, while palatability to a specialist herbivore decreased. Across all species, damage to a neighbor resulted in decreased lifetime fitness, but only if neighbors were closely related. These results suggest that the outcomes of plant signaling within multi-species neighborhoods may be far more context-specific than has been previously shown. In particular, our study shows that herbivore interactions and signaling between plants are contingent on the genetic relationship between neighboring plants. Many factors affect the outcomes of plant signaling, and studies that clarify these factors will be necessary in order to assess the role of plant information exchange about herbivory in natural systems. PMID:22675439
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Paiva, Clemilson Nogueira; Lima, José Wellington de Oliveira; Camelo, Sara Suhett; Lima, Camila de França; Cavalcanti, Luciano Pamplona de Góes
2014-09-01
To evaluate combinations of larvicides and fish which are predators of larvae of Aedes aegypti, namely Betta splendens, Trichogaster trichopterus and Poecilia reticulata. We used 15 water tanks with a capacity of 250 litres of water. In 10 tanks, larvicide - Temephos, Bti and Novaluron - was added, the other five contained only one specimen of fish and unchlorinated water. The fish were monitored for a week without changing the water, and their survival recorded on a form. An estimate of the Kaplan-Meier survival was performed to determine the significance of the tests. Betta splendens showed the lowest mortality range of larvicides tested. Combined use of larvivorous fish and larvicides in large water tanks is feasible. © 2014 John Wiley & Sons Ltd.
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Biodiversity and ecosystem risks arising from using guppies to control mosquitoes
Frauendorf, Therese C.; Marques, Piata S.; Mackenzie, Richard A.; Manna, Luisa R.; Mazzoni, Rosana; Phillip, Dawn A. T.; Warbanski, Misha L.; Zandonà, Eugenia
2016-01-01
Deploying mosquito predators such as the guppy (Poecilia reticulata) into bodies of water where mosquitoes breed is a common strategy for limiting the spread of disease-carrying mosquitoes. Here, we draw on studies from epidemiology, conservation, ecology and evolution to show that the evidence for the effectiveness of guppies in controlling mosquitoes is weak, that the chances of accidental guppy introduction into local ecosystems are large, and that guppies can easily establish populations and damage these aquatic ecosystems. We highlight several knowledge and implementation gaps, and urge that this approach is either abandoned in favour of more effective strategies or that it is used much more rigorously. Controlling mosquitoes does not need to come at the expense of freshwater biodiversity. PMID:28120806
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Sexually dimorphic distribution of galanin in the preoptic area of red salmon, Oncorhynchus nerka.
Jadhao, A G; Meyer, D L
2000-11-01
A sexually dimorphic distribution of galanin in the preoptic region of the molly and goldfish has previously been demonstrated. Females of these species lack galanin-immunoreactive perikarya in the preoptic nucleus. In contrast, we have found, in female red salmon, galanin-immunoreactive neurons in the magnocellular preoptic nucleus, located far lateral to the preoptic recess, whereas many immunoreactive fibers are present in the preoptic area in both genders. In addition, many immunoreactive neurons have been seen in the nucleus preopticus periventricularis and nucleus lateralis tuberis, also in both sexes. These findings support the notion that galanin may play a gender-specific role in red salmon.
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Torres-Dowdall, Julián; Handelsman, Corey A; Reznick, David N; Ghalambor, Cameron K
2012-11-01
Divergent selection pressures across environments can result in phenotypic differentiation that is due to local adaptation, phenotypic plasticity, or both. Trinidadian guppies exhibit local adaptation to the presence or absence of predators, but the degree to which predator-induced plasticity contributes to population differentiation is less clear. We conducted common garden experiments on guppies obtained from two drainages containing populations adapted to high- and low-predation environments. We reared full-siblings from all populations in treatments simulating the presumed ancestral (predator cues present) and derived (predator cues absent) conditions and measured water column use, head morphology, and size at maturity. When reared in presence of predator cues, all populations had phenotypes that were typical of a high-predation ecotype. However, when reared in the absence of predator cues, guppies from high- and low-predation regimes differed in head morphology and size at maturity; the qualitative nature of these differences corresponded to those that characterize adaptive phenotypes in high- versus low-predation environments. Thus, divergence in plasticity is due to phenotypic differences between high- and low-predation populations when reared in the absence of predator cues. These results suggest that plasticity might initially play an important role during colonization of novel environments, and then evolve as a by-product of adaptation to the derived environment. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
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Invasive plants on disturbed Korean sand dunes
NASA Astrophysics Data System (ADS)
Kim, Kee Dae
2005-01-01
The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused by invasive plants. The relationships between the degree of invasion and 14 environmental variables were studied. Plots of sand dunes along line transects perpendicular to the coastal lines were established to estimate vegetative species coverage. TWINSPAN (Two-Way Indicator Species Analysis), CCA (Canonical Correspondence Analysis), and DCCA (Detrended Canonical Correspondence Analysis) were performed to classify communities on sand dunes and assess species composition variation. Carex kobomugi, Elymus mollis, and Vitex rotundifolia were found to be the dominant species plotted on the east, the west, and the peripheral coasts of Cheju Island, respectively. Vegetation on the south coast was totally extinct. The 19 communities, including representative C. kobomugi, C. kobomugi- Ixeris repens, C. kobomugi- Oenothera biennis, E. mollis, Lolium multiflorum- Calystegia soldanella, and V. rotundifolia- C. kobomugi, were all classified according to TWINSPAN. Oenothera biennis and L. multiflorum were exotics observed within these native communities. CCA showed that invasive native and exotic species distribution was segregated significantly, according to disturbance level, exotic species number, gravel, sand and silt contents, as well as vegetation size. It further revealed that human disturbance can strongly favor the settlement of invasive and exotic species. Restoration options to reduce exotic plants in the South Korean sand dune areas were found to be the introduction of native plant species from one sand dune into other sand dune areas, prohibition of building and the introduction of exotic
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Robbers, Lourens F H J; Nijveldt, Robin; Beek, Aernout M; Teunissen, Paul F A; Hollander, Maurits R; Biesbroek, P Stefan; Everaars, Henk; van de Ven, Peter M; Hofman, Mark B M; van Royen, Niels; van Rossum, Albert C
2018-02-01
Native T1 mapping and late gadolinium enhancement (LGE) imaging offer detailed characterisation of the myocardium after acute myocardial infarction (AMI). We evaluated the effects of microvascular injury (MVI) and intramyocardial haemorrhage on local T1 and T2* values in patients with a reperfused AMI. Forty-three patients after reperfused AMI underwent cardiovascular magnetic resonance imaging (CMR) at 4 [3-5] days, including native MOLLI T1 and T2* mapping, STIR, cine imaging and LGE. T1 and T2* values were determined in LGE-defined regions of interest: the MI core incorporating MVI when present, the core-adjacent MI border zone (without any areas of MVI), and remote myocardium. Average T1 in the MI core was higher than in the MI border zone and remote myocardium. However, in the 20 (47%) patients with MVI, MI core T1 was lower than in patients without MVI (MVI 1048±78ms, no MVI 1111±89ms, p=0.02). MI core T2* was significantly lower in patients with MVI than in those without (MVI 20 [18-23]ms, no MVI 31 [26-39]ms, p<0.001). The presence of MVI profoundly affects MOLLI-measured native T1 values. T2* mapping suggested that this may be the result of intramyocardial haemorrhage. These findings have important implications for the interpretation of native T1 values shortly after AMI. • Microvascular injury after acute myocardial infarction affects local T1 and T2* values. • Infarct zone T1 values are lower if microvascular injury is present. • T2* mapping suggests that low infarct T1 values are likely haemorrhage. • T1 and T2* values are complimentary for correctly assessing post-infarct myocardium.
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Male-biased predation of a cave fish by a giant water bug.
Tobler, Michael; Franssen, Courtney M; Plath, Martin
2008-08-01
Male-biased predation has been described from several epigean species, and in many cases, intrinsic differences between the sexes (such as male ornaments) have been suggested as an explanation. Here we report on male-biased predation of a cave fish (Poecilia mexicana) by an aquatic insect (Belostoma sp.) in a Mexican sulfur cave. P. mexicana use aquatic surface respiration (ASR) to survive in their sulfidic, hypoxic habitat. We found that males typically exhibit more ASR activity than females, which leads to increased exposure to the sit-and-wait predator that catches fish near the water surface. Our finding is novel, because male vulnerability to predation is not directly related to male traits involved in courtship, but rather due to other sexual differences in behavior and ultimately, oxygen demands.
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Uveitic secondary glaucoma: influence in James Joyce's (1882-1941) last works.
Ascaso, Francisco J; Bosch, Jordi
2010-02-01
James Joyce, considered one of the pre-eminent novelists of the 20th century, attained international renown with his work Ulysses. Its lack of standard punctuation makes it difficult to read. An example would be the famous non-punctuated 'Molly Bloom soliloquy' in the last chapter of Ulysses. Why is Joyce considered so difficult to read? He wrote and proofread Ulysses and Finnegans wake, his last works, during his battle against glaucoma, when his vision was seriously blurred. The distracting and confusing diacritical marks might be explained by Joyce's reduced visual acuity. Could Ulysses and Finnegans wake have been different if Joyce's visual problems had begun in the second rather than the first half of 20th century?
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Sivagnaname, N; Kalyanasundaram, M
2004-02-01
Methanolic extracts of the leaves of Atlantia monophylla (Rutaceae) were evaluated for mosquitocidal activity against immature stages of three mosquito species, Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti in the laboratory. Larvae of Cx. quinquefasciatus and pupae of An. stephensi were found more susceptible, with LC50 values of 0.14 mg/l and 0.05 mg/l, respectively. Insect growth regulating activity of this extract was more pronounced against Ae. aegypti, with EI50 value 0.002 mg/l. The extract was found safe to aquatic mosquito predators Gambusia affinis, Poecilia reticulata, and Diplonychus indicus, with the respective LC50 values of 23.4, 21.3, and 5.7 mg/l. The results indicate that the mosquitocidal effects of the extract of this plant were comparable to neem extract and certain synthetic chemical larvicides like fenthion, methoprene, etc.
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Swaney, William T; Cabrera-Álvarez, María J; Reader, Simon M
2015-09-01
Predation is an important factor during adaptation to novel environments, and the feralisation of introduced domestic species often involves responding appropriately to allopatric predators despite a background of domestication and inbreeding. Twenty years ago, domestic guppies were introduced to a semi-natural environment at Burgers' Zoo in the Netherlands, where they have since been exposed to avian predation. We compared predation-linked behaviours in this feral population and in domestic guppies akin to the original founders. We found that both populations responded to a novel predator and to conspecific alarm cues. However, shoaling, an important anti-predator behaviour, was higher among feral guppies both at baseline and when exposed to the novel predator. We did not observe a linked suite of anti-predator behaviours across shoaling, predator inspection, alarm substance sensitivity and boldness, suggesting that these responses may be decoupled from one another depending on local predation regimes. As we compared two populations, we cannot identify the causal factors determining population differences, however, our results do suggest that shoaling is either a particularly consequential anti-predator adaptation or the most labile of the behaviours we tested. Finally, the behavioural adaptability of domestic guppies may help to explain their success as an invasive species. Copyright © 2015 Elsevier B.V. All rights reserved.
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Taylor, J S; Breden, F
2000-01-01
The standard slipped-strand mispairing (SSM) model for the formation of variable number tandem repeats (VNTRs) proposes that a few tandem repeats, produced by chance mutations, provide the "raw material" for VNTR expansion. However, this model is unlikely to explain the formation of VNTRs with long motifs (e.g., minisatellites), because the likelihood of a tandem repeat forming by chance decreases rapidly as the length of the repeat motif increases. Phylogenetic reconstruction of the birth of a mitochondrial (mt) DNA minisatellite in guppies suggests that VNTRs with long motifs can form as a consequence of SSM at noncontiguous repeats. VNTRs formed in this manner have motifs longer than the noncontiguous repeat originally formed by chance and are flanked by one unit of the original, noncontiguous repeat. SSM at noncontiguous repeats can therefore explain the birth of VNTRs with long motifs and the "imperfect" or "short direct" repeats frequently observed adjacent to both mtDNA and nuclear VNTRs. PMID:10880490
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DOE Office of Scientific and Technical Information (OSTI.GOV)
van der Wel, H.; Welling, W.
1989-04-01
Acetylcholinesterase activity is a potential biochemical indicator of toxic stress in fish and a sensitive parameter for testing water for the presence of organophosphates. A number of methodological aspects regarding the determination of the in vivo effect of chlorpyrifos on acetylcholinesterase in guppies have been investigated. It was found that with acetylthiocholine as a substrate, the contribution of pseudocholinesterase to the total cholinesterase activity can be neglected. Protection of acetylcholinesterase of guppies exposed to chlorpyrifos from additional, artifactual in vitro enzyme inhibition during homogenization is necessary. Very low concentrations of acetone in the exposure medium, resulting from dilution of themore » stock solution of chlorpyrifos in acetone, can result in large decreases in the oxygen content of this medium. This may affect the uptake rate of the toxic compound and, thereby, cholinesterase inhibition. Very low, sublethal concentrations of chlorpyrifos result in high inhibition levels of acetylcholinesterase (80-90%) in guppies within 2 weeks of continuous exposure. Recovery of the enzyme activity occurs after the exposed animals are kept in clean medium for 4 days, but the rate of recovery is considerably lower than the rate of inhibition.« less
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Cloning controversies: an overview of the science, ethics and politics.
Sharma, B R
2005-01-01
Man's quest for knowledge is boundless. It is because of this quest and his untiring efforts to acquire it, that we have made such tremendous breakthroughs in the fields of science and medicine. Vaccines for hitherto incurable diseases, genetic engineering, and the correction of congenital and hereditary diseases are a few of these. With the successful cloning of 'Dolly', 'Molly' and 'Polly' we are now standing at the threshold of another major breakthrough--human cloning. However, are we ethically, morally and politically mature enough to 'go all the way' in a purely scientific manner, for the benefit of the human kind? A review of the scientific, ethical and political events in this field may be pertinent in trying to answer this important question.
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Bioactive Compounds from Plants Used in Peruvian Traditional Medicine.
Lock, Olga; Perez, Eleucy; Villar, Martha; Flores, Diana; Rojas, Rosario
2016-03-01
It is estimated that there are as many as 1400 plant species currently used in traditional Peruvian medicine; however, only a few have undergone scientific investigation. In this paper, we make a review of the botanical, chemical, pharmacological and clinical propierties of the most investigated Peruvian medicinal plants. The plant species selected for this review are: Smallanthus sonchifolius (yacon), Croton lechleri (sangre de grado), Uncaria tomentosa/U. guianensis (uña de gato), Lepidium meyenii (maca), Physalis peruviana (aguaymanto), Minthostachys mollis (muña), Notholaena nivea (cuti-cuti), Maytenus macrocarpa (chuchuhuasi), Dracontium loretense (jergon sacha), Gentianella nitida (hercampuri), Plukenetia volubilis (sacha inchi) and Zea mays (maiz morado). For each of these plants, information about their traditional uses and current commercialization is also included.
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New Directions for Higher Education: Q&A with ACE's Molly Corbett Broad on Attainment
ERIC Educational Resources Information Center
DiSalvio, Philip
2013-01-01
In April 2013, the "New England Journal of Higher Education" ("NEJHE") launched its "New Directions for Higher Education" series to examine emerging issues, trends, and ideas that have an impact on higher education policies, programs and practices. In this installment of the series, DiSalvio speaks with American…
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Testing Wallace's intuition: water type, reproductive isolation and divergence in an Amazonian fish.
Pires, Tiago H S; Borghezan, Elio A; Machado, Valeria N; Powell, Daniel L; Röpke, Cristhiana P; Oliveira, Claudio; Zuanon, Jansen; Farias, Izeni P
2018-06-01
Alfred Russel Wallace proposed classifying Amazon rivers based on their colour and clarity: white, black and clear water. Wallace also proposed that black waters could mediate diversification and yield distinct fish species. Here, we bring evidence of speciation mediated by water type in the sailfin tetra (Crenuchus spilurus), a fish whose range encompasses rivers of very distinct hydrochemical conditions. Distribution of the two main lineages concords with Wallace's water types: one restricted to the acidic and nutrient-poor waters of the Negro River (herein Rio Negro lineage) and a second widespread throughout the remaining of the species' distribution (herein Amazonas lineage). These lineages occur over a very broad geographical range, suggesting that despite occurring in regions separated by thousands of kilometres, individuals of the distinct lineages fail to occupy each other's habitats, hundreds of metres apart and not separated by physical barrier. Reproductive isolation was assessed in isolated pairs exposed to black-water conditions. All pairs with at least one individual of the lineage not native to black waters showed significantly lower spawning success, suggesting that the water type affected the fitness and contributed to reproductive isolation. Our results endorse Wallace's intuition and highlight the importance of ecological factors in shaping diversity of the Amazon fish fauna. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.
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Evaluation of Cameroonian plants towards experimental bone regeneration.
Ngueguim, Florence Tsofack; Khan, Mohd Parvez; Donfack, Jean Hubert; Siddiqui, Jawed Akhtar; Tewari, Deepshikha; Nagar, Geet K; Tiwari, Satish C; Theophile, Dimo; Maurya, Rakesh; Chattopadhyay, Naibedya
2012-05-07
Elephantopus mollis, Spilanthes africana, Urena lobata, Momordica multiflora, Asystasia gangetica and Brillantaisia ovariensis are used in Cameroonian traditional medicine for the treatment of bone diseases and fracture repair. The aim of this study was to evaluate the effect of ethanolic extracts of six Cameroonian medicinal plants on bone regeneration following bone and marrow injury. Ethanol extract of Cameroonian medicinal plants were administered (each extract at 250, 500 and 750mg/kg doses) orally to adult female Sprague-Dawley rats having a drill hole injury (0.8mm) in the femur diaphysis. Vehicle (gum-acacia in distilled water) was given to the control group. After 12 days of treatment, animals were euthanized and femur bones collected. Confocal microscopy of fractured bone was performed to evaluate bone regeneration (calcein labeling). Only active plant extracts were used for further experiments. Thus, callus was analyzed by microcomputed tomography. Osteogenic effects of the extracts were evaluated by assessing mineralized nodules formation of bone marrow stromal cells and osteoblast recruitment at drill hole site by immunohistochemistry. Ethanolic extract of the leaves and twigs of Elephantopus mollis (EM) and whole plant of Spilanthes africana (SA) dose-dependently stimulated bone regeneration at the drill hole site. EM at 250 and 750mg/kg doses and SA at 750mg/kg dose significantly increased mineral deposition compared to controls. Both extracts at 500 and 750mg/kg doses improved microarchitecture of the regenerating bone evident from increased bone volume fraction, trabecular thickness, trabecular number, and decreased trabecular separation and structure model index. EM and SA extracts increased the formation of mineralized nodules from the bone marrow stromal cells. In addition, EM and SA extracts increased osteoblast recruitment at the drill hole site evident from increased Runx-2 positive cells following their treatments compared to control
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Dekić, Svjetlana; Klobučar, Göran; Ivanković, Tomislav; Zanella, Davor; Vucić, Matej; Bourdineaud, Jean-Paul; Hrenović, Jasna
2018-05-08
Bacterium Acinetobacter baumannii is an emerging human pathogen whose presence in the aquatic environment raises the issue of public health risk. Fish colonization represents the potential route of pathogen transmission to humans. The aim was to examine the colonization of A. baumannii to freshwater fish Poecilia reticulata. An extensively drug-resistant A. baumannii was tested at three concentrations in natural spring water. Additionally, 70 fish from the Sava River (Croatia) were screened for the presence of A. baumannii, which was not found in gill swabs or analysed gut. The colonization potential of A. baumannii in freshwater fish is dependent upon its concentration in surrounding water. The low concentration of A. baumannii in natural waters represents low colonization potential of freshwater fish. The risk for public health exists in closed water bodies where there is constant inflow of water polluted by A. baumannii in concentrations above 3 log CFU mL -1 .
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Cenotes (sinkholes) of the Yucatan Peninsula, Mexico, as a habitat of adult trematodes of fish.
Scholz, T; Vargas-Vázquez, J; Moravec, F; Vivas-Rodríguez, C; Mendoza-Franco, E
1995-01-01
Examination of a total of 581 fish specimens of 15 species from 39 cenotes (sinkholes) in the Yucatan Peninsula, southeastern Mexico, revealed the presence of 10 species of adult trematodes. These were as follows: Saccocoelioides sogandaresi Lumsden, 1963, Saccocoelioides sp. (family Haploporidae), Cichlasotrema ujati Pineda et Andrade, 1989 (Angiodictyidae), Crassicutis cichlasomae Manter, 1936 (Homalometridae), Magnivitellinum simplex Kloss, 1966 (Macroderoididae), Stunkardiella minima (Stunkard, 1938) (Acanthostomidae), Oligogonotylus manteri Watson, 1976 (Cryptogonimidae), Genarchella tropica (Manter, 1936), G. astyanactis (Watson, 1976), and G. isabellae (Lamothe-Argumedo, 1977) (Derogenidae). Saccocoelioides sogandaresi is reported from Mexico for the first time. Poecilia velifera and P. latipunctata for S. sogandaresi, Cichlasoma octofasciatum for C. cichlasomae, Cichlasoma friedrichstahli and C. meeki for O. manteri, and C. meeki, C. octofasciatum and Gobiomorus dormitor for G. isabellae represent new host records. Most species found are described and figured and their host range and distribution are discussed.
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Virtual Reality: You Are There
NASA Technical Reports Server (NTRS)
1993-01-01
Telepresence or "virtual reality," allows a person, with assistance from advanced technology devices, to figuratively project himself into another environment. This technology is marketed by several companies, among them Fakespace, Inc., a former Ames Research Center contractor. Fakespace developed a teleoperational motion platform for transmitting sounds and images from remote locations. The "Molly" matches the user's head motion and, when coupled with a stereo viewing device and appropriate software, creates the telepresence experience. Its companion piece is the BOOM-the user's viewing device that provides the sense of involvement in the virtual environment. Either system may be used alone. Because suits, gloves, headphones, etc. are not needed, a whole range of commercial applications is possible, including computer-aided design techniques and virtual reality visualizations. Customers include Sandia National Laboratories, Stanford Research Institute and Mattel Toys.
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Kaarthigeyan, J; Dharmaretnam, Meena
2005-04-15
Cerebral lateralisation once thought to be confined to humans has been reported for a range of vertebrate species now. We report here biases in visual perceptual processing in a teleost fish. Female guppy fish used the right eye preferentially to view a familiar stimulus. This bias reversed on being presented with a strange female guppy, the left eye being used more to view it. This pattern of viewing is probably associated with the right eye system, which is used to view a stimulus with an intention to approach it. The increase in the left eye use, to view a stranger may be associated with the role of the left eye in comparing the features of a strange conspecific. In the second experiment, lateralisation of viewing visual stimuli that could evoke different levels of motivation to biologically relevant stimuli was tested. It is known that female guppies prefer to approach orange coloured males. Lateralisation of detour response as well as eye use after detour to view a dull or an orange male stimulus was recorded in deprived female fish. There was a bias to detour to the left side; which was more significant for the orange than the dull male. Once the female guppies detoured the cage they preferentially used the left eye to view the male conspecific; this being significant for the deeply orange male. Thus, colouration of males evoking different levels motivation can be used to measure lateralisation in guppies.
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Disease Mapping for Stomach Cancer in Libya Based on Besag– York– Mollié (BYM) Model
Alhdiri, Maryam Ahmed Salem; Samat, Nor Azah; Mohamed, Zulkifley
2017-06-25
Globally, Cancer is the ever-increasing health problem and most common cause of medical deaths. In Libya, it is an important health concern, especially in the setting of an aging population and limited healthcare facilities. Therefore, the goal of this research is to map of the county’ cancer incidence rate using the Bayesian method and identify the high-risk regions (for the first time in a decade). In the field of disease mapping, very little has been done to address the issue of analyzing sparse cancer diseases in Libya. Standardized Morbidity Ratio or SMR is known as a traditional approach to measure the relative risk of the disease, which is the ratio of observed and expected number of accounts in a region that has the greatest uncertainty if the disease is rare or small geographical region. Therefore, to solve some of SMR’s problems, we used statistical smoothing or Bayesian models to estimate the relative risk for stomach cancer incidence in Libya in 2007 based on the BYM model. This research begins with a short offer of the SMR and Bayesian model with BYM model, which we applied to stomach cancer incidence in Libya. We compared all of the results using maps and tables. We found that BYM model is potentially beneficial, because it gives better relative risk estimates compared to SMR method. As well as, it has can overcome the classical method problem when there is no observed stomach cancer in a region. Creative Commons Attribution License
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Ostrowski de Núñez, M; Quintana, M G
2008-03-01
A new species, Stephanoprora aylacostoma is described and its life cycle was resolved experimentally. The prosobranch snail Aylacostoma chloroticum Hylton Scott, collected in the Yacyretá dam, Province of Misiones, Argentina, was found naturally infected with large-tailed cercariae possessing a prepharyngeal body and corpuscles in the excretory system but lacking collar spines. Metacercariae, which encysted on the gills of experimentally infected fishes Cnesterodon decemmaculatus (Jenyns) and Poecilia reticulata (Peters) (Poecilidae), developed collar spines after 10 days. Tetragonopterid fishes Moenckhausia dichroura (Kner), Astyanax erythropterus (Holmberg) and Hyphesobrycon serpae (Durbin in Eigenmann) were found infected naturally. Sexually mature adults were recovered from domestic chicks at day 7 post-exposure. Eggs shed in chick faeces developed to miracidia within 13-15 days; sporocysts were found on the gills of snails. The new species differs from other species of the genus in its larger eggs, in the smaller, slender body and smaller collar spines of the adult and in the morphological and biological features of the larval stages.
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Wang, Qiang; Jia, Qingzhu; Yan, Lihong; Xia, Shuqian; Ma, Peisheng
2014-08-01
The aquatic toxicity value of hazardous contaminants plays an important role in the risk assessments of aquatic ecosystems. The following study presents a stable and accurate structure-toxicity relationship model based on the norm indexes for the prediction of toxicity value (log(LC50)) for 190 diverse narcotic pollutants (96 h LC50 data for Poecilia reticulata). Research indicates that this new model is very efficient and provides satisfactory results. The suggested prediction model is evidenced by R(2) (square correlation coefficient) and ARD (average relative difference) values of 0.9376 and 10.45%, respectively, for the training set, and 0.9264 and 13.90% for the testing set. Comparison results with reference models demonstrate that this new method, based on the norm indexes proposed in this work, results in significant improvements, both in accuracy and stability for predicting aquatic toxicity values of narcotic pollutants. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Size-mediated response to public cues of predation risk in a tropical stream fish.
Elvidge, C K; Ramnarine, I W; Godin, J-G J; Brown, G E
2010-11-01
In order to investigate any size-dependent differences between behavioural patterns, wild-caught Hart's rivulus Rivulus hartii of varying sizes were exposed to chemical alarm cues extracted from the skin of conspecifics or heterospecific Poecilia reticulata, or a tank water control, in a series of laboratory trials. In response to conspecific alarm cues, R. hartii subjects of the range of body sizes tested exhibited consistent, size-independent antipredator behaviours that were characterized by decreased locomotory activity and foraging levels and increased refuging behaviour. Conversely, focal R. hartii demonstrated significant size-dependent trends in response to heterospecific alarm cues, with smaller individuals exhibiting antipredator responses and larger individuals shifting their behaviour to increased levels of activity consistent with a foraging, or predatory, response. These results show that the behavioural responses of individual R. hartii to publicly available chemical alarm cues from heterospecifics are mediated by the size of the receiver. © 2010 The Authors. Journal of Fish Biology © 2010 The Fisheries Society of the British Isles.
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Fear of predation drives stable and differentiated social relationships in guppies
Heathcote, Robert J. P.; Darden, Safi K.; Franks, Daniel W.; Ramnarine, Indar W.; Croft, Darren P.
2017-01-01
Social relationships can have important consequences for fitness in animals. Whilst numerous studies have shown that individuals often join larger groups in response to perceived predation risk (i.e. fear of predation), the importance of predation risk in driving the formation and stability of social relationships within groups has been relatively ignored. We experimentally tested how predation threat influenced fine-scale social network structure using Trinidadian guppies (Poecilia reticulata). When perceived predation risk was high, individuals developed stable and more differentiated social ties compared to when perceived risk was low. Intriguingly, social differentiation coincided with shoals being somewhat smaller under high-perceived risk, suggesting a possible conflict between forming stable social relationships and larger social groups. Individuals most at risk of predation (large and bold individuals) showed the most exaggerated responses in several social measures. Taken together, we provide the first experimental evidence that proximate risk of predation can increase the intensity of social relationships and fine-scale social structure in animal populations. PMID:28150706
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Fear of predation drives stable and differentiated social relationships in guppies.
Heathcote, Robert J P; Darden, Safi K; Franks, Daniel W; Ramnarine, Indar W; Croft, Darren P
2017-02-02
Social relationships can have important consequences for fitness in animals. Whilst numerous studies have shown that individuals often join larger groups in response to perceived predation risk (i.e. fear of predation), the importance of predation risk in driving the formation and stability of social relationships within groups has been relatively ignored. We experimentally tested how predation threat influenced fine-scale social network structure using Trinidadian guppies (Poecilia reticulata). When perceived predation risk was high, individuals developed stable and more differentiated social ties compared to when perceived risk was low. Intriguingly, social differentiation coincided with shoals being somewhat smaller under high-perceived risk, suggesting a possible conflict between forming stable social relationships and larger social groups. Individuals most at risk of predation (large and bold individuals) showed the most exaggerated responses in several social measures. Taken together, we provide the first experimental evidence that proximate risk of predation can increase the intensity of social relationships and fine-scale social structure in animal populations.
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Levy, G; Zilberg, D; Paladini, G; Fridman, S
2015-04-30
Monogenean infections of commercially farmed fishes are responsible for significant economic losses and existing chemical therapeutants, often stressful to the fish, pose associated risks. As part of a recent trend to move towards the use of alternative, plant-based remedies for commonly occurring aquaculture-related diseases, the efficiency of ginger (Zingiber officinale) was investigated against the monogenean parasite Gyrodactylus turnbulli in the guppy. In vitro trials revealed the clear anti-parasitic effects of ginger. Ethanolic and aqueous extracts, prepared from freeze dried ginger, were tested. An increase in extract concentration was associated with reduced time to parasite immobilisation, with ethanolic extract being more efficient; at 75 and 200ppt aqueous ginger extract parasites died at 65.6±2.8 and 1.8±0.2min, respectively, whereas at 5 and 40ppt ethanolic extract parasites died at 26.1±0.7 and 4.9±0.3min, respectively. Bathing G. turnbulli-infected fish in ethanolic ginger extract (i.e. 5 and 7.5ppt for 90 and 30min, respectively) significantly reduced infection prevalence and intensity when compared to the water and ethanol controls. The higher concentration (i.e. 7.5ppt) proved as equally effective as Praziquantel, the conventionally used chemical treatment for gyrodactylosis, with the fish appearing to be completely cleared of the infection in both cases. Oral treatments of G. turnbulli-infected guppies with diets supplemented with 10 and 20% ginger powder proved to be ineffective in decreasing parasite load. These findings demonstrate that immersion in ginger extract offers an effective, alternative treatment against monogenean infection in fish. Copyright © 2015 Elsevier B.V. All rights reserved.
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Mann, Alfred E
2006-01-01
In this wide-ranging interview, Alfred Mann describes the activities of several medical technology enterprises with which he is engaged. Several of them are companies that he formed; one is a nonprofit foundation, the Alfred E. Mann Foundation for Biomedical Engineering, founded to establish research-oriented institutes on a dozen university campuses and support their work in developing marketable innovations. Mann discusses the need to consider the cost implications of technology, in the context of U.S. health system reform, and describes several important innovations that have emerged from his companies over the years.
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NASA Astrophysics Data System (ADS)
Rothballer, K.; Sturges, M. J.
2016-12-01
Join veteran artist/activist Molly Sturges for a presentation on FIREROCK: PASS THE SPARK performances and engagement processes that foster personal and collective creativity for sustained climate engagement and collaborative leadership. FIREROCK: PASS THE ROCK opens in San Francisco in October 2016. This project is an evolving, long-term, social innovation project that has been developed with faith, Indigenous and directly impacted communities as well as schools, towns and universities. Informed by science, social justice, Indigenous knowledge, and grassroots activism FIREROCK includes performances that are accompanied by a series of activities designed to build community and engineer creative spaces for dialogue and response. The FIREROCK team has found that people are excited to engage around climate when there are venues available for expressivity and meaningful exchange. FIREROCK supports us in moving from our current stance in which we are paralyzed— often not knowing what to do or how to act—to seeing ourselves as part of the solution. FIREROCK is a family-friendly catalytic musical journey inviting people into the complexity of climate change and sparking an inspired response to the mythic challenges of our time. Through story, song and unique engagement experiences, FIREROCK builds community towards action and solutions. FIREROCK provides partners with everything they need to make the project their own, including a comprehensive toolkit to assist groups in learning how to develop community partnerships, convene FIREROCK engagement activities and facilitate dialogue and skill sharing. This dynamic storytelling project is scalable and can be employed, adapted and localized by groups and communities nationwide as a powerful catalyst for climate engagement work. Molly Sturges is a national leader in arts, ecology and social change work. She is the Founding Artistic Director of Littleglobe, a diverse arts cooperative made up of artistic and cultural workers
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2012-01-01
Background T2w-CMR is used widely to assess myocardial edema. Quantitative T1-mapping is also sensitive to changes in free water content. We hypothesized that T1-mapping would have a higher diagnostic performance in detecting acute edema than dark-blood and bright-blood T2w-CMR. Methods We investigated 21 controls (55 ± 13 years) and 21 patients (61 ± 10 years) with Takotsubo cardiomyopathy or acute regional myocardial edema without infarction. CMR performed within 7 days included cine, T1-mapping using ShMOLLI, dark-blood T2-STIR, bright-blood ACUT2E and LGE imaging. We analyzed wall motion, myocardial T1 values and T2 signal intensity (SI) ratio relative to both skeletal muscle and remote myocardium. Results All patients had acute cardiac symptoms, increased Troponin I (0.15-36.80 ug/L) and acute wall motion abnormalities but no LGE. T1 was increased in patient segments with abnormal and normal wall motion compared to controls (1113 ± 94 ms, 1029 ± 59 ms and 944 ± 17 ms, respectively; p < 0.001). T2 SI ratio using STIR and ACUT2E was also increased in patient segments with abnormal and normal wall motion compared to controls (all p < 0.02). Receiver operator characteristics analysis showed that T1-mapping had a significantly larger area-under-the-curve (AUC = 0.94) compared to T2-weighted methods, whether the reference ROI was skeletal muscle or remote myocardium (AUC = 0.58-0.89; p < 0.03). A T1 value of greater than 990 ms most optimally differentiated segments affected by edema from normal segments at 1.5 T, with a sensitivity and specificity of 92 %. Conclusions Non-contrast T1-mapping using ShMOLLI is a novel method for objectively detecting myocardial edema with a high diagnostic performance. T1-mapping may serve as a complementary technique to T2-weighted imaging for assessing myocardial edema in ischemic and non-ischemic heart disease, such as quantifying area-at-risk and diagnosing
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Bader, E J
1990-04-01
The war on the women of America is being actively repelled through the efforts on Molly Yard and the National Organization for Women (NOW), Tamar Abrams and the National Abortion Rights Action League, the Freedom Caravan for Women's Lives, and the many women actively supporting pro-choice. At issue is the Supreme Court decision in Webster v. Reproductive Health Services which limits women's right to choose. It is feared that the Court will proceed with overturning Roe v. Wade, which gives women the right to terminate unwanted pregnancies; 7 states are attempting to ban abortion entirely: Arkansas, Idaho, Illinois, Kentucky, Louisiana, Missouri and South Dakota. 6 are expected to maintain legal rights: Alaska, Hawaii, Main, Oregon, Vermont, and Washington. The political pro-choice strategy has been to organize protest activities where there was a challenge to pro-choice--in Florida, California, and in gubernatorial races in New Jersey and Virginia. Voters were mobilized by telephone, newspaper ads, and cable television promotions outlining pro-choice positions. Success was achieved in both state gubernatorial elections, and in California's replacement assemblyman race with Tricia Hunter winning against 7 anti-choice contenders. The Caravan which began on Women's Equality day on August 26, 1989 in Atlantic City, New Jersey (NJ) raised $10,000 for the NJ lobbying effort; walkathons and lobbying activity maximized the impact. For example, there was a rally in a solidly Republican city where the antiabortion candidate support was strong; the pro-choice support was evident. The RU-486, an effective abortifacient, manufacturer with offices in NJ was approached with 1000 cards of support. The Florida special legislative session antiabortion effort was defeated, but pressure will be maintained on the Governor and antichoice legislators. Pro-choice Democrat Douglas Wilder of Virginia, who was the state's 1st black legislator, was supported and won the election. Even though
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NASA Astrophysics Data System (ADS)
Ochs, Michael Ann; Mc Leod, Roger D.; Mc Leod, Edward M.
2003-10-01
Katahdin (Christ Cathar Spirit-signal stronghold) in Maine is sacred to the Penobscot Indian Nation. That mountain complex, and areas like Ellis Pond, ME and Penley Hill/Anasagunticook (adherent of Jesus Christ Spirit-signal doctor church) of the Mexico/Rumford/Mountain Valley region, also in Maine, have an association with historic Native Americans like the medicine woman Molocket/Molly Ockett. We have observed that these and other regions generate electromagnetic field (EMF) signals, which we can detect visually and in other ways. Such signals have sometimes been associated with significant and dynamic weather phenomena. Ohio's Serpent Mound and associated regions, or those now occupied by the Hopi Indian Nation, formerly an ancient Anasazi site, or areas of the current and earlier Mayan Nations, or the Nazca Plateau of Peru, may generate signals correlating with climate change, that may impact our technology, as in major power blackouts.
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Sex-Specific Differences in Shoaling Affect Parasite Transmission in Guppies
Richards, E. Loys; van Oosterhout, Cock; Cable, Joanne
2010-01-01
Background Individuals have to trade-off the costs and benefits of group membership during shoaling behaviour. Shoaling can increase the risk of parasite transmission, but this cost has rarely been quantified experimentally. Guppies (Poecilia reticulata) are a model system for behavioural studies, and they are commonly infected by gyrodactylid parasites, notorious fish pathogens that are directly transmitted between guppy hosts. Methodology/Principal Findings Parasite transmission in single sex shoals of male and female guppies were observed using an experimental infection of Gyrodactylus turnbulli. Parasite transmission was affected by sex-specific differences in host behaviour, and significantly more parasites were transmitted when fish had more frequent and more prolonged contact with each other. Females shoaled significantly more than males and had a four times higher risk to contract an infection. Conclusions/Significance Intersexual differences in host behaviours such as shoaling are driven by differences in natural and sexual selection experienced by both sexes. Here we show that the potential benefits of an increased shoaling tendency are traded off against increased risks of contracting an infectious parasite in a group-living species. PMID:20949014
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Costs of colour change in fish: food intake and behavioural decisions.
Rodgers, Gwendolen M; Gladman, Nicholas W; Corless, Hannah F; Morrell, Lesley J
2013-07-15
Many animals, particularly reptiles, amphibians, fish and cephalopods, have the ability to change their body colour, for functions including thermoregulation, signalling and predator avoidance. Many fish plastically darken their body colouration in response to dark visual backgrounds, and this functions to reduce predation risk. Here, we tested the hypotheses that colour change in fish (1) carries with it an energetic cost and (2) affects subsequent shoal and habitat choice decisions. We demonstrate that guppies (Poecilia reticulata) change colour in response to dark and light visual backgrounds, and that doing so carries an energetic cost in terms of food consumption. By increasing food intake, however, guppies are able to maintain growth rates and meet the energetic costs of changing colour. Following colour change, fish preferentially choose habitats and shoals that match their own body colouration, and maximise crypsis, thus avoiding the need for further colour change but also potentially paying an opportunity cost associated with restriction to particular habitats and social associates. Thus, colour change to match the background is complemented by behavioural strategies, which should act to maximise fitness in variable environments.
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Schooling preferences for familiar fish vary with group size in a wild guppy population
Griffiths, S. W.; Magurran, A. E.
1997-01-01
The ability of fish to recognize and preferentially associate with familiar conspecifics has been well documented in a series of laboratory experiments. In this paper we investigate the schooling preferences of wild female guppies, Poecilia reticulata, in the Upper Tunapuna River in Trinidad and confirm that they do indeed prefer to associate with familiar individuals. The guppies in this river occur in a series of pools that become isolated during the dry season. These fish interact solely with other individuals in their pool for periods of several months at a time and thus have ample opportunity to become accustomed to one another. Our study also reveals that the tendency of female guppies to school with familiar fish declines as the group size in which they naturally live increases. Preferences are strong when there are small numbers of females in a pool, but diminish thereafter. This indicates that the expression of familiarity is constrained by group size. The basis of recognition and the consequences of schooling preferences for familiar individuals are discussed.
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el-Matbouli, M; Hoffmann, R W; Schoel, H; McDowell, T S; Hedrick, R P
1999-01-07
Scanning electron microscopic studies were conducted on rainbow trout Oncorhynchus mykiss in the first 60 min after their exposure to the triactinomyxon spores of Myxobolus cerebralis. The results demonstrated that as early as 1 min post exposure the whole process, from the attachment of the triactinomyxon spores to the complete penetration of their sporoplasm germs, had occurred. The triactinomyxon spores sought out the secretory openings of mucous cells of the epidermis, the respiratory epithelium and the buccal cavity of trout and used them as portals of entry. Exposure experiments of the triactinomyxon spores of M. cerebralis to non-salmonid fish, such as goldfish Carassius auratus, carp Cyprinus carpio, nose Chondrostoma nasus, medaka Oryzias latipes, guppy Poecilia reticulata and also the amphibian tadpole Rana pipiens as well as to rainbow trout fry indicated a specificity for salmonids. Attempts to activate the triactinomyxon spores by exposure to mucus prepared from cyprinid and salmonid fish showed no significant differences from those conducted in tap water. The results suggest that the simultaneous presence of both mechano- and chemotactic stimuli was required for finding the salmonid fish host.
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Sexual display and mate choice in an energetically costly environment.
Head, Megan L; Wong, Bob B M; Brooks, Robert
2010-12-09
Sexual displays and mate choice often take place under the same set of environmental conditions and, as a consequence, may be exposed to the same set of environmental constraints. Surprisingly, however, very few studies consider the effects of environmental costs on sexual displays and mate choice simultaneously. We conducted an experiment, manipulating water flow in large flume tanks, to examine how an energetically costly environment might affect the sexual display and mate choice behavior of male and female guppies, Poecilia reticulata. We found that male guppies performed fewer sexual displays and became less choosy, with respect to female size, in the presence of a water current compared to those tested in still water. In contrast to males, female responsive to male displays did not differ between the water current treatments and females exhibited no mate preferences with respect to male size or coloration in either treatment. The results of our study underscore the importance of considering the simultaneous effects of environmental costs on the sexual behaviors of both sexes.
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NASA Astrophysics Data System (ADS)
Wang, Bangping; Li, Zhenxing; Zheng, Lina; Liu, Yixuan; Lin, Hong
2011-03-01
As fish is one source of the `big eight' food allergens, the prevalence of fish allergy has increased over the past few years. In order to better understand fish allergy, it is necessary to identify fish allergens. Based on the sera from fish-allergenic patients, a 28 kDa protein from local mackerel ( Scomber japonicus), which has not been reported as a fish allergen, was found to be reactive with most of the patients' sera. The 28 kDa protein was analyzed by MALDI-TOF-MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry). Mascot search in NCBI database (Date: 08/07/2010) showed that the top protein matched, i.e. triosephosphate isomerase (TPI) from Xiphophorus maculatus and Poecilia reticulata, had a mowse (molecular weight search) score of 98. In addition, TPI from Epinephelus coioides also matched this mackerel protein with a mowse score of 96. Because TPI is considered as an allergen in other non-fish organisms, such as lychee, wheat, latex, archaeopotamobius ( Archaeopotamobius sibiriensis) and crangon ( Crangon crangon), we consider that it may also be an allergen in mackerel.
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Using video playbacks to study visual communication in a marine fish, Salaria pavo.
Gonçalves; Oliveira; Körner; Poschadel; Schlupp
2000-09-01
Video playbacks have been successfully applied to the study of visual communication in several groups of animals. However, this technique is controversial as video monitors are designed with the human visual system in mind. Differences between the visual capabilities of humans and other animals will lead to perceptually different interpretations of video images. We simultaneously presented males and females of the peacock blenny, Salaria pavo, with a live conspecific male and an online video image of the same individual. Video images failed to elicit appropriate responses. Males were aggressive towards the live male but not towards video images of the same male. Similarly, females courted only the live male and spent more time near this stimulus. In contrast, females of the gynogenetic poecilid Poecilia formosa showed an equal preference for a live and video image of a P. mexicana male, suggesting a response to live animals as strong as to video images. We discuss differences between the species that may explain their opposite reaction to video images. Copyright 2000 The Association for the Study of Animal Behaviour.
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Charlesworth, Deborah
2018-01-01
Sex chromosomes regularly evolve suppressed recombination, distinguishing them from other chromosomes, and the reason for this has been debated for many years. It is now clear that non-recombining sex-linked regions have arisen in different ways in different organisms. A major hypothesis is that a sex-determining gene arises on a chromosome and that sexually antagonistic (SA) selection (sometimes called intra-locus sexual conflict) acting at a linked gene has led to the evolution of recombination suppression in the region, to reduce the frequency of low fitness recombinant genotypes produced. The sex chromosome system of the guppy (Poecilia reticulata) is often cited as supporting this hypothesis because SA selection has been demonstrated to act on male coloration in natural populations of this fish, and probably contributes to maintaining polymorphisms for the genetic factors involved. I review classical genetic and new molecular genetic results from the guppy, and other fish, including approaches for identifying the genome regions carrying sex-determining loci, and suggest that the guppy may exemplify a recently proposed route to sex chromosome evolution. PMID:29783761
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Speciation in caves: experimental evidence that permanent darkness promotes reproductive isolation
Riesch, Rüdiger; Plath, Martin; Schlupp, Ingo
2011-01-01
Divergent selection through biotic factors like predation or parasitism can promote reproductive isolation even in the absence of geographical barriers. On the other hand, evidence for a role of adaptation to abiotic factors during ecological speciation in animals is scant. In particular, the role played by perpetual darkness in establishing reproductive isolation in cave animals (troglobites) remains elusive. We focused on two reproductively isolated ecotypes (surface- and cave-dwelling) of the widespread livebearer Poecilia mexicana, and raised offspring of wild-caught females to sexual maturity in a 12-month common-garden experiment. Fish were reared in light or darkness combined with high- or low-food conditions. Females, but not males, of the surface ecotype suffered from almost complete reproductive failure in darkness, especially in the low-food treatment. Furthermore, surface fish suffered from a significantly higher rate of spontaneous, stress-related infection with bacterial columnaris disease. This experimental evidence for strong selection by permanent darkness on non-adapted surface-dwelling animals adds depth to our understanding of the selective forces establishing and maintaining reproductive isolation in cave faunas. PMID:21561964
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Artificial selection for food colour preferences
Cole, Gemma L.; Endler, John A.
2015-01-01
Colour is an important factor in food detection and acquisition by animals using visually based foraging. Colour can be used to identify the suitability of a food source or improve the efficiency of food detection, and can even be linked to mate choice. Food colour preferences are known to exist, but whether these preferences are heritable and how these preferences evolve is unknown. Using the freshwater fish Poecilia reticulata, we artificially selected for chase behaviour towards two different-coloured moving stimuli: red and blue spots. A response to selection was only seen for chase behaviours towards the red, with realized heritabilities ranging from 0.25 to 0.30. Despite intense selection, no significant chase response was recorded for the blue-selected lines. This lack of response may be due to the motion-detection mechanism in the guppy visual system and may have novel implications for the evolvability of responses to colour-related signals. The behavioural response to several colours after five generations of selection suggests that the colour opponency system of the fish may regulate the response to selection. PMID:25740894
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Development of the Hearts of Lizards and Snakes and Perspectives to Cardiac Evolution
Jensen, Bjarke; van den Berg, Gert; van den Doel, Rick; Oostra, Roelof-Jan; Wang, Tobias; Moorman, Antoon F. M.
2013-01-01
Birds and mammals both developed high performance hearts from a heart that must have been reptile-like and the hearts of extant reptiles have an unmatched variability in design. Yet, studies on cardiac development in reptiles are largely old and further studies are much needed as reptiles are starting to become used in molecular studies. We studied the growth of cardiac compartments and changes in morphology principally in the model organism corn snake (Pantherophis guttatus), but also in the genotyped anole (Anolis carolinenis and A. sagrei) and the Philippine sailfin lizard (Hydrosaurus pustulatus). Structures and chambers of the formed heart were traced back in development and annotated in interactive 3D pdfs. In the corn snake, we found that the ventricle and atria grow exponentially, whereas the myocardial volumes of the atrioventricular canal and the muscular outflow tract are stable. Ventricular development occurs, as in other amniotes, by an early growth at the outer curvature and later, and in parallel, by incorporation of the muscular outflow tract. With the exception of the late completion of the atrial septum, the adult design of the squamate heart is essentially reached halfway through development. This design strongly resembles the developing hearts of human, mouse and chicken around the time of initial ventricular septation. Subsequent to this stage, and in contrast to the squamates, hearts of endothermic vertebrates completely septate their ventricles, develop an insulating atrioventricular plane, shift and expand their atrioventricular canal toward the right and incorporate the systemic and pulmonary venous myocardium into the atria. PMID:23755108
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The behavioural response of adult Petromyzon marinus to damage-released alarm and predator cues
Imre, István; Di Rocco, Richard; Belanger, Cowan; Brown, Grant; Johnson, Nicholas S.
2014-01-01
Using semi-natural enclosures, this study investigated (1) whether adult sea lamprey Petromyzon marinus show avoidance of damage-released conspecific cues, damage-released heterospecific cues and predator cues and (2) whether this is a general response to injured heterospecific fishes or a specific response to injured P. marinus. Ten replicate groups of 10 adult P. marinus, separated by sex, were exposed to one of the following nine stimuli: deionized water (control), extracts prepared from adult P. marinus, decayed adult P. marinus (conspecific stimuli), sympatric white sucker Catostomus commersonii, Amazon sailfin catfish Pterygoplichthys pardalis (heterospecific stimuli), 2-phenylethylamine (PEA HCl) solution, northern water snake Nerodia sipedon washing, human saliva (predator cues) and an adult P. marinus extract and human saliva combination (a damage-released conspecific cue and a predator cue). Adult P. marinus showed a significant avoidance response to the adult P. marinus extract as well as to C. commersonii, human saliva, PEA and the adult P. marinus extract and human saliva combination. For mobile P. marinus, the N. sipedon washing induced behaviour consistent with predator inspection. Exposure to the P. pardalis extract did not induce a significant avoidance response during the stimulus release period. Mobile adult female P. marinus showed a stronger avoidance behaviour than mobile adult male P. marinus in response to the adult P. marinus extract and the adult P. marinus extract and human saliva combination. The findings support the continued investigation of natural damage-released alarm cue and predator-based repellents for the behavioural manipulation of P. marinus populations in the Laurentian Great Lakes.
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Haubruge, E; Petit, F; Gage, M J
2000-01-01
There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function. PMID:11413652
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Haubruge, E; Petit, F; Gage, M J
2000-11-22
There is increasing evidence that normal male reproductive function can be disrupted by exposure to pollutants in the environment that can exogenously mimic, antagonize or block sex-hormone function. One possible consequence of exposure to these xenobiotics is disruption to spermatogenesis, but results thus far provide only indirect and inconsistent evidence. In this study we exposed adult male guppies (Poeciliidae: Teleostei) to environmentally relevant levels of the common xenobiotics tributyltin (11.2-22.3 ngl-1) and bisphenol A (274-549 micrograms l-1) in experimental aquaria. After 21 days of exposure, we found significant declines (by 40-75%) in total sperm counts for male fishes exposed to tributyltin and bisphenol A compared with controls. This short-term decline in sperm count is unlikely to be the result of endocrine-mediated alteration of the germ line, and we found no change in testis size or sperm lengths between treatments. However, Sertoli cells, which facilitate the transport of maturing sperm into the testicular deferent duct (where they are stored prior to ejaculation), are directly sensitive to xenobiotic action and it is therefore possible that spermatogenesis was inhibited through in vivo interference with normal Sertoli-cell function.
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Pérez, Glòria; Gotsens, Mercè; Palència, Laia; Marí-Dell'Olmo, Marc; Domínguez-Berjón, M Felicitas; Rodríguez-Sanz, Maica; Puig, Vanessa; Bartoll, Xavier; Gandarillas, Ana; Martín, Unai; Bacigalupe, Amaia; Díez, Elia; Ruiz, Miguel; Esnaola, Santiago; Calvo, Montserrat; Sánchez, Pablo; Luque Fernández, Miguel Ángel; Borrell, Carme
The aim is to present the protocol of the two sub-studies on the effect of the economic crisis on mortality and reproductive health and health inequalities in Spain. Substudy 1: describe the evolution of mortality and reproductive health between 1990 and 2013 through a longitudinal ecological study in the Autonomous Communities. This study will identify changes caused by the economic crisis in trends or reproductive health and mortality indicators using panel data (17 Autonomous Communities per study year) and adjusting Poisson models with random effects variance. Substudy 2: analyse inequalities by socioeconomic deprivation in mortality and reproductive health in several areas of Spain. An ecological study analysing trends in the pre-crisis (1999-2003 and 2004-2008) and crisis (2009-2013) periods will be performed. Random effects models Besag York and Mollié will be adjusted to estimate mortality indicators softened in reproductive health and census tracts. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.
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Timing of ore-related magmatism in the western Alaska Range, southwestern Alaska
Taylor, Ryan D.; Graham, Garth E.; Anderson, Eric D.; Selby, David
2014-01-01
This report presents isotopic age data from mineralized granitic plutons in an area of the Alaska Range located approximately 200 kilometers to the west-northwest of Anchorage in southwestern Alaska. Uranium-lead isotopic data and trace element concentrations of zircons were determined for 12 samples encompassing eight plutonic bodies ranging in age from approximately 76 to 57.4 millions of years ago (Ma). Additionally, a rhenium-osmium age of molybdenite from the Miss Molly molybdenum occurrence is reported (approx. 59 Ma). All of the granitic plutons in this study host gold-, copper-, and (or) molybdenum-rich prospects. These new ages modify previous interpretations regarding the age of magmatic activity and mineralization within the study area. The new ages show that the majority of the gold-quartz vein-hosting plutons examined in this study formed in the Late Cretaceous. Further work is necessary to establish the ages of ore-mineral deposition in these deposits.
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Improving respiration measurements with gas exchange analyzers.
Montero, R; Ribas-Carbó, M; Del Saz, N F; El Aou-Ouad, H; Berry, J A; Flexas, J; Bota, J
2016-12-01
Dark respiration measurements with open-flow gas exchange analyzers are often questioned for their low accuracy as their low values often reach the precision limit of the instrument. Respiration was measured in five species, two hypostomatous (Vitis Vinifera L. and Acanthus mollis) and three amphistomatous, one with similar amount of stomata in both sides (Eucalyptus citriodora) and two with different stomata density (Brassica oleracea and Vicia faba). CO 2 differential (ΔCO 2 ) increased two-fold with no change in apparent R d , when the two leaves with higher stomatal density faced outside. These results showed a clear effect of the position of stomata on ΔCO 2 . Therefore, it can be concluded that leaf position is important to guarantee the improvement of respiration measurements increasing ΔCO 2 without affecting the respiration results by leaf or mass units. This method will help to increase the accuracy of leaf respiration measurements using gas exchange analyzers. Copyright © 2016 Elsevier GmbH. All rights reserved.
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Mosquito repellent activity of essential oils of aromatic plants growing in Argentina.
Gillij, Y G; Gleiser, R M; Zygadlo, J A
2008-05-01
Mosquitoes are important vectors of diseases and nuisance pests. Repellents minimize contact with mosquitoes. Repellents based on essential oils (EO) are being developed as an alternative to DEET (N,N-diethyl-m-methylbenzamide), an effective compound that has disadvantages including toxic reactions, and damage to plastic and synthetic fabric. This work evaluated the repellency against Aedes aegypti of EO from aromatic plants that grow in Argentina: Acantholippia seriphioides, Achyrocline satureioides, Aloysia citriodora, Anemia tomentosa, Baccharis spartioides, Chenopodium ambrosioides, Eucalyptus saligna, Hyptis mutabilis, Minthostachys mollis, Rosmarinus officinalis, Tagetes minuta and Tagetes pusilla. Most EO were effective. Variations depending on geographic origin of the plant were detected. At a 90% EO concentration, A. satureoides and T. pusilla were the least repellent. At concentrations of 12.5% B. spartioides, R. officinalis and A. citriodora showed the longest repellency times. Comparisons of the principal components of each EO suggest that limonene and camphor were the main components responsible for the repellent effects.
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Baggott, Matthew J; Coyle, Jeremy R; Siegrist, Jennifer D; Garrison, Kathleen J; Galloway, Gantt P; Mendelson, John E
2016-04-01
The drug 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy", "molly") is a widely used illicit drug and experimental adjunct to psychotherapy. MDMA has unusual, poorly understood socioemotional effects, including feelings of interpersonal closeness and sociability. To better understand these effects, we conducted a small (n=12) within-subjects double-blind placebo controlled study of the effects of 1.5 mg/kg oral MDMA on social emotions and autobiographical disclosure in a controlled setting. MDMA displayed both sedative- and stimulant-like effects, including increased self-report anxiety. At the same time, MDMA positively altered evaluation of the self (i.e. increasing feelings of authenticity) while decreasing concerns about negative evaluation by others (i.e. decreasing social anxiety). Consistent with these feelings, MDMA increased how comfortable participants felt describing emotional memories. Overall, MDMA produced a prosocial syndrome that seemed to facilitate emotional disclosure and that appears consistent with the suggestion that it represents a novel pharmacological class. © The Author(s) 2016.
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What's in a label? Ecstasy sellers' perceptions of pill brands.
Duterte, Micheline; Jacinto, Camille; Sales, Paloma; Murphy, Sheigla
2009-03-01
This article presents selected findings from a qualitative study of Ecstasy sellers and their sales practices, knowledge of distribution networks, buyer-seller relationships, and self-reported drug use. In-depth interviews were conducted with 80 men and women who had sold five or more hits of Ecstasy five or more times in the six months prior to the interview. Study participants described their perceptions of the various types of Ecstasy they had distributed or used themselves. The participants had experience with a variety of Ecstasy labels, from the popular "Blue Dolphin" tablets to the powdered form called "Molly." We tracked pill brand mentions on Ecstasy-related websites to compare with interviewees' descriptions of Ecstasy brands. This study examines Ecstasy sellers' ideas about the role of brand names in Ecstasy markets and their relationship to their beliefs about different types of Ecstasy's purity and quality. We demonstrate that considering Ecstasy branding increases our understanding of buyer and seller relationships.
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What’s in a Label? Ecstasy Sellers’ Perceptions of Pill Brands†
Duterte, Micheline; Jacinto, Camille; Sales, Paloma; Murphy, Sheigla
2009-01-01
This article presents selected findings from a qualitative study of Ecstasy sellers and their sales practices, knowledge of distribution networks, buyer-seller relationships, and self-reported drug use. In-depth interviews were conducted with 80 men and women who had sold five or more hits of Ecstasy five or more times in the six months prior to the interview. Study participants described their perceptions of the various types of Ecstasy they had distributed or used themselves. The participants had experience with a variety of Ecstasy labels, from the popular “Blue Dolphin” tablets to the powdered form called “Molly.” We tracked pill brand mentions on Ecstasy-related websites to compare with interviewees’ descriptions of Ecstasy brands. This study examines Ecstasy sellers’ ideas about the role of brand names in Ecstasy markets and their relationship to their beliefs about different types of Ecstasy’s purity and quality. We demonstrate that considering Ecstasy branding increases our understanding of buyer and seller relationships. PMID:19455907
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Santos-Oliveira, Ralph; Lima-Ribeiro, Maria Helena Madruga; Carneiro-Leão, Ana Maria dos Anjos; Cruz, Adriana Ferreira; de Santana, Mauricélia Firmino; Cavalcanti, Carmelita de Lima Bezerra; de Pontes Filho, Nicodemos Teles; Coelho, Luana Cassandra Breitenbach Barroso; dos Santos Correia, Maria Tereza
2013-01-01
Context: Regeneration corresponds to the replacement of damaged cells with ones that have the same morphology and function. For experimental evaluation of materials that may favor the process of bone healing, defects are created with dimensions that prevent spontaneous regeneration. For the development and use of new drugs, it is necessary to study its effects in vitro, which depends on the formulation, concentration, and rate of irradiation in vivo and the route and frequency of administration; thus, it is possible to characterize the physiological and molecular mechanisms involved in the response and cellular effects. Objective: The objective of this study was to assess the effect of Cramoll-1,4 on the process of bone repair. Materials and Methods: A formulation of biopharmaceutical lectin Cramoll-1,4 at a concentration of 300 mg/100 mL was applied in a single application via gamma radiation and its effect on the process of bone repair in rats was assessed. Results: Histologically, it was observed that the bone defect is coated by loose connective tissue rich in fibroblasts, providing a range similar to the thick bone original and competing with site of new bone formation. This prevented direct contact between the formulation and experimental bone tissue, as, despite its proven effectiveness in experiments on the repair of skin lesions, the formulation used did not promote bone stimulation that would have promoted the tissue repair process. Conclusion: Because of the direct interference of loose tissue repair that prevented direct contact of the implant with the bone interface, the formulation did not promote bone stimulation. PMID:24083142
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[Ichthyofauna of karstic wetlands under anthropic impact: the "petenes" of Campeche, Mexico].
Torres-Castro, Ivette Liliana; Vega-Cendejas, María Eugenia; Schmitter-Soto, Juan Jacobo; Palacio-Aponte, Gerardo; Rodiles-Hernández, Rocío
2009-01-01
"Petenes" are small springs and associated streams that drain into wetlands near the coast in karstic areas. We studied composition, distribution, and abundance of the ichthyofauna in Los Petenes region (northwest Campeche). Two petenes displaying different degrees and types of anthropic impact were selected, Hampolol and El Remate. Hampolol has a smaller area but a longer derived stream; it is located within a protected area, but has been invaded by tilapia. El Remate is a popular spa, with no tilapia; it has a larger area but a shorter derived stream. At each "petén", several sites in the main spring, the associated stream, and secondary (temporary) springs were sampled in the rainy and dry seasons. Fishing gear was variable (throw net, gill net, small and large seine nets), but effort was uniform. We recorded temperature, dissolved oxygen, salinity, and depth at each site and season; also, we noted the different types and intensities of anthropic impact (channelization, presence of exotic species, recreational use, etc.) at each petén. We compared the petenes in terms of their environmental quality and fish fauna (composition, distribution, abundance, biomass); we also tested for effects of season and site within each petén. The study found 27 species of fishes, included in 18 genera and eight families, 24 species in Hampolol and 20 in El Remate. The geographical range of 'Cichlasoma' salvini, Rivulus tenuis, Phallichthys fairweatheri, Xiphophorus hellerii, and X maculatus is extended. The dominant species in both seasons was Astyanax (probable hybrids A. aeneus x altior at Hampolol, pure A. altior at El Remate), which contributed most of the abundance and biomass, together with Vieja synspila and Poecilia velifera. A significantly greater overall diversity (H'n=3.31) was recorded in Hampolol compared to El Remate (H'n=2.10). Cluster analysis of sites by species presence allowed distinction of two groupings within each petén: permanent waters (i.e., main
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Model for estimating enteric methane emissions from United States dairy and feedlot cattle.
Kebreab, E; Johnson, K A; Archibeque, S L; Pape, D; Wirth, T
2008-10-01
Methane production from enteric fermentation in cattle is one of the major sources of anthropogenic greenhouse gas emission in the United States and worldwide. National estimates of methane emissions rely on mathematical models such as the one recommended by the Intergovernmental Panel for Climate Change (IPCC). Models used for prediction of methane emissions from cattle range from empirical to mechanistic with varying input requirements. Two empirical and 2 mechanistic models (COWPOLL and MOLLY) were evaluated for their prediction ability using individual cattle measurements. Model selection was based on mean square prediction error (MSPE), concordance correlation coefficient, and residuals vs. predicted values analyses. In dairy cattle, COWPOLL had the lowest root MSPE and greatest accuracy and precision of predicting methane emissions (correlation coefficient estimate = 0.75). The model simulated differences in diet more accurately than the other models, and the residuals vs. predicted value analysis showed no mean bias (P = 0.71). In feedlot cattle, MOLLY had the lowest root MSPE with almost all errors from random sources (correlation coefficient estimate = 0.69). The IPCC model also had good agreement with observed values, and no significant mean (P = 0.74) or linear bias (P = 0.11) was detected when residuals were plotted against predicted values. A fixed methane conversion factor (Ym) might be an easier alternative to diet-dependent variable Ym. Based on the results, the 2 mechanistic models were used to simulate methane emissions from representative US diets and were compared with the IPCC model. The average Ym in dairy cows was 5.63% of GE (range 3.78 to 7.43%) compared with 6.5% +/- 1% recommended by IPCC. In feedlot cattle, the average Ym was 3.88% (range 3.36 to 4.56%) compared with 3% +/- 1% recommended by IPCC. Based on our simulations, using IPCC values can result in an overestimate of about 12.5% and underestimate of emissions by about 9.8% for
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Habituation of adult sea lamprey repeatedly exposed to damage-released alarm and predator cues
Imre, Istvan; Di Rocco, Richard T.; Brown, Grant E.; Johnson, Nicholas
2016-01-01
Predation is an unforgiving selective pressure affecting the life history, morphology and behaviour of prey organisms. Selection should favour organisms that have the ability to correctly assess the information content of alarm cues. This study investigated whether adult sea lamprey Petromyzon marinus habituate to conspecific damage-released alarm cues (fresh and decayed sea lamprey extract), a heterospecific damage-released alarm cue (white sucker Catostomus commersoniiextract), predator cues (Northern water snake Nerodia sipedon washing, human saliva and 2-phenylethylamine hydrochloride (PEA HCl)) and a conspecific damage-released alarm cue and predator cue combination (fresh sea lamprey extract and human saliva) after they were pre-exposed 4 times or 8 times, respectively, to a given stimulus the previous night. Consistent with our prediction, adult sea lamprey maintained an avoidance response to conspecific damage-released alarm cues (fresh and decayed sea lamprey extract), a predator cue presented at high relative concentration (PEA HCl) and a conspecific damage-released alarm cue and predator cue combination (fresh sea lamprey extract plus human saliva), irrespective of previous exposure level. As expected, adult sea lamprey habituated to a sympatric heterospecific damage-released alarm cue (white sucker extract) and a predator cue presented at lower relative concentration (human saliva). Adult sea lamprey did not show any avoidance of the Northern water snake washing and the Amazon sailfin catfish extract (heterospecific control). This study suggests that conspecific damage-released alarm cues and PEA HCl present the best options as natural repellents in an integrated management program aimed at controlling the abundance of sea lamprey in the Laurentian Great Lakes.
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The behavioural response of adult Petromyzon marinus to damage-released alarm and predator cues.
Imre, I; Di Rocco, R T; Belanger, C F; Brown, G E; Johnson, N S
2014-05-01
Using semi-natural enclosures, this study investigated (1) whether adult sea lamprey Petromyzon marinus show avoidance of damage-released conspecific cues, damage-released heterospecific cues and predator cues and (2) whether this is a general response to injured heterospecific fishes or a specific response to injured P. marinus. Ten replicate groups of 10 adult P. marinus, separated by sex, were exposed to one of the following nine stimuli: deionized water (control), extracts prepared from adult P. marinus, decayed adult P. marinus (conspecific stimuli), sympatric white sucker Catostomus commersonii, Amazon sailfin catfish Pterygoplichthys pardalis (heterospecific stimuli), 2-phenylethylamine (PEA HCl) solution, northern water snake Nerodia sipedon washing, human saliva (predator cues) and an adult P. marinus extract and human saliva combination (a damage-released conspecific cue and a predator cue). Adult P. marinus showed a significant avoidance response to the adult P. marinus extract as well as to C. commersonii, human saliva, PEA and the adult P. marinus extract and human saliva combination. For mobile P. marinus, the N. sipedon washing induced behaviour consistent with predator inspection. Exposure to the P. pardalis extract did not induce a significant avoidance response during the stimulus release period. Mobile adult female P. marinus showed a stronger avoidance behaviour than mobile adult male P. marinus in response to the adult P. marinus extract and the adult P. marinus extract and human saliva combination. The findings support the continued investigation of natural damage-released alarm cue and predator-based repellents for the behavioural manipulation of P. marinus populations in the Laurentian Great Lakes. © 2014 The Fisheries Society of the British Isles.
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ERIC Educational Resources Information Center
Bhroimeil, Una Ni
2006-01-01
This article examines a decision known as Rule 127(b), taken in 1905 by the National Commissioners for Education in Ireland. The rule raised concerns about the displacement of male teachers and their replacement with poorly paid and sometimes untrained females. It appeared to condone the sexual division of labour with women teaching in infant…
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Imprinting can cause a maladaptive preference for infectious conspecifics.
Stephenson, Jessica F; Reynolds, Michael
2016-04-01
Recognizing and associating with specific individuals, such as conspecifics or kin, brings many benefits. One mechanism underlying such recognition is imprinting: the long-term memory of cues encountered during development. Typically, juveniles imprint on cues of nearby individuals and may later associate with phenotypes matching their 'recognition template'. However, phenotype matching could lead to maladaptive social decisions if, for instance, individuals imprint on the cues of conspecifics infected with directly transmitted diseases. To investigate the role of imprinting in the sensory ecology of disease transmission, we exposed juvenile guppies,Poecilia reticulata, to the cues of healthy conspecifics, or to those experiencing disease caused by the directly transmitted parasite Gyrodactylus turnbulli In a dichotomous choice test, adult 'disease-imprinted' guppies preferred to associate with the chemical cues of G. turnbulli-infected conspecifics, whereas 'healthy-imprinted' guppies preferred to associate with cues of uninfected conspecifics. These responses were only observed when stimulus fish were in late infection, suggesting imprinted fish responded to cues of disease, but not of infection alone. We discuss how maladaptive imprinting may promote disease transmission in natural populations of a social host. © 2016 The Author(s).
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Imprinting can cause a maladaptive preference for infectious conspecifics
2016-01-01
Recognizing and associating with specific individuals, such as conspecifics or kin, brings many benefits. One mechanism underlying such recognition is imprinting: the long-term memory of cues encountered during development. Typically, juveniles imprint on cues of nearby individuals and may later associate with phenotypes matching their ‘recognition template’. However, phenotype matching could lead to maladaptive social decisions if, for instance, individuals imprint on the cues of conspecifics infected with directly transmitted diseases. To investigate the role of imprinting in the sensory ecology of disease transmission, we exposed juvenile guppies, Poecilia reticulata, to the cues of healthy conspecifics, or to those experiencing disease caused by the directly transmitted parasite Gyrodactylus turnbulli. In a dichotomous choice test, adult ‘disease-imprinted’ guppies preferred to associate with the chemical cues of G. turnbulli-infected conspecifics, whereas ‘healthy-imprinted’ guppies preferred to associate with cues of uninfected conspecifics. These responses were only observed when stimulus fish were in late infection, suggesting imprinted fish responded to cues of disease, but not of infection alone. We discuss how maladaptive imprinting may promote disease transmission in natural populations of a social host. PMID:27072405
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Riesch, Rüdiger; Martin, Ryan A; Langerhans, R Brian
2013-01-01
Populations experiencing consistent differences in predation risk and resource availability are expected to follow divergent evolutionary trajectories. For example, live-history theory makes specific predictions for how predation should drive life-history evolution, and according to the Trexler-DeAngelis model for the evolution of matrotrophy, postfertilization maternal provisioning is most likely to evolve in environments with consistent, high levels of resource availability. Using the model system of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes with and without the piscivorous bigmouth sleeper (Gobiomorus dormitor), we provide some of the strongest tests of these predictions to date, as resource availability does not covary with predation regime in this system, and we examine numerous (14) isolated natural populations. We found clear evidence for the expected life-history divergence between predation regimes and empirical support of the Trexler-DeAngelis model. Moreover, based on molecular and lab-rearing data, our study offers strong evidence for convergent evolution of similar life histories in similar predation regimes, largely matching previous phenotypic patterns observed in other poeciliid lineages (Brachyrhaphis spp., Poecilia reticulata), and further supports the notion that matrotrophy is most likely to evolve in stable high-resource environments.
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Artificial selection for food colour preferences.
Cole, Gemma L; Endler, John A
2015-04-07
Colour is an important factor in food detection and acquisition by animals using visually based foraging. Colour can be used to identify the suitability of a food source or improve the efficiency of food detection, and can even be linked to mate choice. Food colour preferences are known to exist, but whether these preferences are heritable and how these preferences evolve is unknown. Using the freshwater fish Poecilia reticulata, we artificially selected for chase behaviour towards two different-coloured moving stimuli: red and blue spots. A response to selection was only seen for chase behaviours towards the red, with realized heritabilities ranging from 0.25 to 0.30. Despite intense selection, no significant chase response was recorded for the blue-selected lines. This lack of response may be due to the motion-detection mechanism in the guppy visual system and may have novel implications for the evolvability of responses to colour-related signals. The behavioural response to several colours after five generations of selection suggests that the colour opponency system of the fish may regulate the response to selection. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
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Guppies as predators of common mosquito larvae in Malaysia.
Saleeza, S N R; Norma-Rashid, Y; Sofian-Azirun, M
2014-03-01
Observation on predation activities of guppies (Poecilia reticulata) on the larvae of three species of mosquito, namely Aedes albopictus, Aedes aegypti, and Culex quinquefasciatus was carried out under laboratory conditions. Male and female guppies were used as predators for predation experiments on the 4th instars of mosquito larvae. The daily feeding rates comparing male and female guppies on mosquito larvae were different; the female guppies consumed more mosquito larvae than male guppies did. The daily feeding rates of female guppies were 121.3 for Ae. aegypti, 105.6 for Ae. albopictus, and 72.3 for Cx. quinquefasciatus. The daily feeding rates of male guppies were 98.6 for Ae. aegypti, 73.6 for Ae. albopictus, and 47.6 for Cx. quinquefasciatus. In terms of prey preference, there was greater preference towards mosquito larvae of Ae. aegypti, followed by Ae. albopictus, and the least preferred was Cx. quinquefasciatus. Male and female guppies consumed more mosquito larvae during lights on (day time) compared with lights off (night time). The water volume, prey species, number of fish predators available, prey densities, and prey's sex also influenced the predation activities.
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Palkovacs, Eric P.; Wasserman, Ben A.; Kinnison, Michael T.
2011-01-01
Ecosystems are being altered on a global scale by the extirpation of top predators. The ecological effects of predator removal have been investigated widely; however, predator removal can also change natural selection acting on prey, resulting in contemporary evolution. Here we tested the role of predator removal on the contemporary evolution of trophic traits in prey. We utilized a historical introduction experiment where Trinidadian guppies (Poecilia reticulata) were relocated from a site with predatory fishes to a site lacking predators. To assess the trophic consequences of predator release, we linked individual morphology (cranial, jaw, and body) to foraging performance. Our results show that predator release caused an increase in guppy density and a “sharpening” of guppy trophic traits, which enhanced food consumption rates. Predator release appears to have shifted natural selection away from predator escape ability and towards resource acquisition ability. Related diet and mesocosm studies suggest that this shift enhances the impact of guppies on lower trophic levels in a fashion nuanced by the omnivorous feeding ecology of the species. We conclude that extirpation of top predators may commonly select for enhanced feeding performance in prey, with important cascading consequences for communities and ecosystems. PMID:21526156
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Detection of mycobacteria in aquarium fish in Slovenia by culture and molecular methods.
Pate, M; Jencic, V; Zolnir-Dovc, M; Ocepek, M
2005-04-06
Thirty-five aquarium fish were investigated for the presence of mycobacteria by culture and molecular methods. The following species were examined: goldfish Carassius auratus auratus, guppy Poecilia reticulata, 4 three-spot gourami Trichogaster trichopterus, dwarf gourami Colisa lalia, Siamese fighting fish Betta splendens, freshwater angelfish Pterophyllum scalare, African cichlid fish Cichlidae spp., cichlid fish Microgeophagus altispinosus, cichlid fish Pseudotropheus lombardoi, blue streak hap Labidochromis caeruleus, sterlet Acipenser ruthenus, southern platyfish Xiphophorus maculatus, and catfish Corydoras spp. Isolates of mycobacteria were obtained in 29 cases (82.9%). Two specimens were positive using Ziehl-Neelsen (ZN) staining, but the cultivation failed. Four specimens were both ZN- and culture-negative. On the basis of GenoType Mycobacterium assay (Hain Life-science) and restriction enzyme analysis of the amplified products (PCR-RFLP), 23 isolates (79.3%) were identified: 7 as Mycobacterium fortuitum, 6 as M. gordonae, 6 as M. marinum, 3 as M. chelonae, and 1 as M. peregrinum. Five isolates remained unidentified (Mycobacterium spp.). One case probably represented a mixed infection (M. marinum/M. fortuitum). Since M. marinum infections are also detected in humans, the significance of mycobacteria in aquarium fish should not be overlooked.
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AlShebly, Mashael Marzouq; AlQahtani, Fatma Saeed; Govindarajan, Marimuthu; Gopinath, Kasi; Vijayan, Periasamy; Benelli, Giovanni
2017-03-01
Mosquitoes act as vectors of key pathogens and parasites. Plant essential oils have been recognized as important sources of biopesticides, which do not induce resistance and have limited toxic effects on human health and non-target organisms. In this research, we evaluated the larvicidal and oviposition deterrence activity of Hedychium larsenii essential oil (EO) and its major compounds ar-curcumene and epi-β-bisabolol. Both molecules showed high toxicity against early third instars of Anopheles stephensi (LC 50 =10.45 and 14.68µg/ml), Aedes aegypti (LC 50 =11.24 and 15.83µg/ml) and Culex quinquefasciatus (LC 50 =12.24 and 17.27µg/ml). In addition, low doses of ar-curcumene and epi-β-bisabolol were effective as oviposition deterrents against the three tested mosquito species. Notably, the acute toxicity of H. larsenii oil and its major compounds against the mosquito biocontrol agent Poecilia reticulata was low, with LC 50 higher than 1500ppm. Overall, the results from this study revealed that ar-curcumene and epi-β-bisabolol from the H. larsenii oil can be considered for the development of novel and effective mosquito larvicides. Copyright © 2016 Elsevier Inc. All rights reserved.
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Verma, Priyanka; Mathur, Ajay Kumar; Jain, Sheetal Prasad; Mathur, Archana
2012-01-01
Twenty-three pharmaceutically important plants, namely, Elaeocarpus spharicus, Rheum emodi, Indigofera tinctoria, Picrorrhiza kurroa, Bergenia ciliata, Lavandula officinalis, Valeriana wallichii, Coleus forskohlii, Gentiana kurroo, Saussurea lappa, Stevia rebaudiana, Acorus calamus, Pyrethrum cinerariaefolium, Aloe vera, Bacopa monnieri, Salvia sclarea, Glycyrrhiza glabra, Swertia cordata, Psoralea corylifolia, Jurinea mollis, Ocimum sanctum, Paris polyphylla, and Papaver somniferum, which are at the verge of being endangered due to their overexploitation and collection from the wild, were successfully established in vitro. Collections were made from the different biodiversity zones of India including Western Himalaya, Northeast Himalaya, Gangetic plain, Western Ghats, Semiarid Zone, and Central Highlands. Aseptic cultures were raised at the morphogenic level of callus, suspension, axillary shoot, multiple shoot, and rooted plants. Synseeds were also produced from highly proliferating shoot cultures of Bacopa monnieri, Glycyrrhiza glabra, Stevia rebaudiana, Valeriana wallichii, Gentiana kurroo, Lavandula officinalis, and Papaver somniferum. In vitro flowering was observed in Papaver somniferum, Psoralea corylifolia, and Ocimum sanctum shoots cultures. Out of 23 plants, 18 plants were successfully hardened under glasshouse conditions. PMID:22593711
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The educational situation in Utopia: why what is, is
NASA Astrophysics Data System (ADS)
Seaman, Jayson; Quay, John
2015-03-01
In this response to Molly Ware's review of our 2013 book, John Dewey and Education Outdoors, we extend her suggestion that complexity be regarded as an important, generative force in education reform. Drawing on Dewey's 1933 Utopian Schools speech, we discuss the "level deeper" that Dewey sought as he criticized the method/subject mater dichotomy, which he saw as an artifact of social class carried forward in the form of a curricular debate rather than a natural source of tension that would be productive to democratic education. Dewey radically argued that learning itself contained similar anti-democratic potential. Eschewing the false child versus curriculum dichotomy, Dewey believed complexity as a catalyst for educational action would be achieved by engaging children in historically formed occupations, harnessing the forces that drive technological and cultural evolution in order to spur interest, effort, and the formation of social attitudes among students. Following Ware, we suggest that reformers should seek to understand at a lever deeper the many sources of complexity they encounter as they both challenge and honor what is.
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[Geographical factors in the epidemiology of intoxication with Karwinskia (tullidora) in Mexico].
Nava, M E; Castellanos, J L; Castañeda, M E
2000-01-01
Consumption of fruits from the genus Karwinskia may cause a flaccid paralysis that can be confused with the Guillan-Barré syndrome or poliomyelitis. Paralysis resulting from consumption of such fruit has emerged as a public health problem in certain regions of Mexico. The purpose of this study was to investigate geographical factors associated with this intoxication in the 72 cases reported in Mexico from 1990 to 1994. Location of cases coincides with the distribution of the 11 reported species of Karwinskia in the country. The majority of reported cases were related to the consumption of K. humboldtiana, with a smaller number involving K. mollis, K. parvifolia, K. johnstonii, and K. rzedowskii. Most cases were located in regions with dry climates (79.2%), arid vegetation (41. 7%), and altitudes under 1,000 meters above sea level (54.1%). The study establishes three different risk areas: the Balsas river region in the southwestern central part of the country; the arid northern area; and the arid and dry central area. Cases were from rural communities with low levels of schooling and poor socioeconomic conditions.
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Talbot, S. S.; Talbot, S.L.; Walker, L.R.
2010-01-01
We studied the vegetation of Kasatochi Island, central Aleutian Islands, to provide a general field assessment regarding the survival of plants, lichens, and fungi following a destructive volcanic eruption that occurred in 2008. Plant community data were analyzed using multivariate methods to explore the relationship between pre- and post-eruption plant cover; 5 major vegetation types were identified: Honckenya peploides beach, Festuca rubra cliff shelf, Lupinus nootkatensisFestuca rubra meadow, Leymus mollis bluff ridge (and beach), and Aleuria aurantia lower slope barrens. Our study provided a very unusual glimpse into the early stages of plant primary succession on a remote island where most of the vegetation was destroyed. Plants that apparently survived the eruption dominated early plant communities. Not surprisingly, the most diverse post-eruption community most closely resembled a widespread pre-eruption type. Microhabitats where early plant communities were found were distinct and apparently crucial in determining plant survival. Comparison with volcanic events in related boreal regions indicated some post-eruption pattern similarities. ?? 2010 Regents of the University of Colorado.
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Views of STS-3 crew during departure activites at Ellington with family
NASA Technical Reports Server (NTRS)
1982-01-01
Views of STS-3 crew, Astronauts Jack R. Lousma, left, and C. Gordon Fullerton prior to their departure in T-38 aircraft from Ellington Air Force Base for the launch of STS-3 (28700); Some of the family members of astronaut crew are greeted by a crowd of spectators on hand for Lousma and Fullerton's departure. Matthew Lousma is standing at the microphone in center of the frame, flanked by Mrs. Gratia Kay Lousma (left) and Mrs. Maria Fullerton. Left to right in front are Mary Lousma, Andrew Fullerton and Molly Fullerton (28701-2); Astronaut Lousma walks away from microphone after greeting news media representatives and public prior to departure for Kennedy (28703); Astronaut Lousma talking to Fullerton, left, and Astronuat Brewster H. Shaw, center before boarding T-38's to leave for KSC (28704); Lousma, left, and Fullerton pause at Ellington prior to their departure in T-38 aircraft for KSC (28705); Lousma, right, and Fullerton greet crowd on hand at Ellington for their departure to KSC
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2017-09-14
Spacecraft operations team manager for the Cassini mission at Saturn, Julie Webster, second from right, talks about her experiences with Cassini during the Cassini NASA Social, Thursday, Sept. 14, 2017 at NASA's Jet Propulsion Laboratory in Pasadena, California. Also participating in the engineering panel was Cassini program manager at JPL, Earl Maize, right, guidance and control engineer for the Cassini mission at Saturn, Luis Andrade, second from left, and mission planner for the Cassini mission at Saturn, Molly Bittner, left. Since its arrival in 2004, the Cassini-Huygens mission has been a discovery machine, revolutionizing our knowledge of the Saturn system and captivating us with data and images never before obtained with such detail and clarity. On Sept. 15, 2017, operators will deliberately plunge the spacecraft into Saturn, as Cassini gathered science until the end. The “plunge” ensures Saturn’s moons will remain pristine for future exploration. During Cassini’s final days, mission team members from all around the world gathered at NASA’s Jet Propulsion Laboratory, Pasadena, California, to celebrate the achievements of this historic mission. Photo Credit: (NASA/Joel Kowsky)
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Anti-quorum sensing activity of essential oils from Colombian plants.
Jaramillo-Colorado, Beatriz; Olivero-Verbel, Jesus; Stashenko, Elena E; Wagner-Döbler, Irene; Kunze, Brigitte
2012-01-01
Essential oils from Colombian plants were characterised by GC-MS, and assayed for anti-quorum sensing activity in bacteria sensor strains. Two major chemotypes were found for Lippia alba, the limonene-carvone and the citral (geranial-neral). For other species, the main components included α-pinene (Ocotea sp.), β-pinene (Swinglea glutinosa), cineol (Elettaria cardamomun), α-zingiberene (Zingiber officinale) and pulegone (Minthostachys mollis). Several essential oils presented promising inhibitory properties for the short chain AHL quorum sensing (QS) system, in Escherichia coli containing the biosensor plasmid pJBA132, in particular Lippia alba. Moderate activity as anti-QS using the same plasmid, were also found for selected constituents of essential oils studied here, such as citral, carvone and α-pinene, although solely at the highest tested concentration (250 µg mL(-1)). Only citral presented some activity for the long chain AHL QS system, in Pseudomonas putida containing the plasmid pRK-C12. In short, essential oils from Colombian flora have promising properties as QS modulators.
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Measurement of myocardial native T1 in cardiovascular diseases and norm in 1291 subjects.
Liu, Joanna M; Liu, Alexander; Leal, Joana; McMillan, Fiona; Francis, Jane; Greiser, Andreas; Rider, Oliver J; Myerson, Saul; Neubauer, Stefan; Ferreira, Vanessa M; Piechnik, Stefan K
2017-09-28
Native T1-mapping provides quantitative myocardial tissue characterization for cardiovascular diseases (CVD), without the need for gadolinium. However, its translation into clinical practice is hindered by differences between techniques and the lack of established reference values. We provide typical myocardial T1-ranges for 18 commonly encountered CVDs using a single T1-mapping technique - Shortened Look-Locker Inversion Recovery (ShMOLLI), also used in the large UK Biobank and Hypertrophic Cardiomyopathy Registry study. We analyzed 1291 subjects who underwent CMR (1.5-Tesla, MAGNETOM-Avanto, Siemens Healthcare, Erlangen, Germany) between 2009 and 2016, who had a single CVD diagnosis, with mid-ventricular T1-map assessment. A region of interest (ROI) was placed on native T1-maps in the "most-affected myocardium", characterized by the presence of late gadolinium enhancement (LGE), or regional wall motion abnormalities (RWMA) on cines. Another ROI was placed in the "reference myocardium" as far as possible from LGE/RWMA, and in the septum if no focal abnormality was present. To further define normality, we included native T1 of healthy subjects from an existing dataset after sub-endocardial pixel-erosions. Native T1 of patients with normal CMR (938 ± 21 ms) was similar compared to healthy subjects (941 ± 23 ms). Across all patient groups (57 ± 19 yrs., 65% males), focally affected myocardium had significantly different T1 value compared to reference myocardium (all p < 0.001). In the affected myocardium, cardiac amyloidosis (1119 ± 61 ms) had the highest native T1 compared to normal and all other CVDs, while iron-overload (795 ± 58 ms) and Anderson-Fabry disease (863 ± 23 ms) had the lowest native reference T1 (all p < 0.001). Future studies designed to detect the large T1 differences between affected and reference myocardium are estimated to require small sample-sizes (n < 50). However, studies designed to detect the small T1
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Weil, R E; Spade, D J; Knoebl, I; Hemming, J M; Tongue, M L; Szabo, N J; Kroll, K J; Tate, W B; Denslow, N D
2012-04-01
The threatened Okaloosa darter (Etheostoma okaloosae) is found almost exclusively on the Eglin Air Force Base in the Choctawhatchee Bay watershed of Florida. Portions of this limited habitat are threatened with soil erosion, altered hydrology, and impaired water quality. In the present study, general water quality parameters (i.e., dissolved oxygen, specific conductance, pH, temperature, relative turbidity, and primary productivity) were characterized in East Turkey Creek, which is a body of water potentially impacted by treated wastewater sprayfields, and Long Creek, an adjacent reference stream that does not border the sprayfields. Water quality was assessed during a 30-day exposure using passive samplers for both non-polar and polar effluent parameters. Because the Okaloosa darter was listed as endangered at the time of sampling we chose a closely related species from the same creeks, the sailfin shiner (Pteronotropis hypseleotris) in which to measure metal body burdens. Additionally, fathead minnows (Pimephales promelas) were used for microarray analysis on gonad and liver tissues after 48 h exposures to water collected from the two creeks and brought into the laboratory. Waters from all sites, including reference sites, affected the expression of genes related to various biological processes including transcription and translation, cell cycle control, metabolism, and signaling pathways, suggesting that the sum of anthropogenic compounds in the site waters may cause a generalized stress response in both liver and testis, an effect that could be related to the generally low populations of the Okaloosa darter. Furthermore, effects of site waters on fish gene expression may be related to the impact of human activities other than the wastewater sprayfields, as nearby areas are closed to the public for military testing, training, and administrative activities and due to ordnance contamination. Copyright © 2012 Elsevier B.V. All rights reserved.
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Fish responses to flow velocity and turbulence in relation to size, sex and parasite load
Hockley, F. A.; Wilson, C. A. M. E.; Brew, A.; Cable, J.
2014-01-01
Riverine fish are subjected to heterogeneous flow velocities and turbulence and may use this to their advantage by selecting regions that balance energy expenditure for station holding while maximizing energy gain through feeding opportunities. This study investigated microhabitat selection by guppies Poecilia reticulata in terms of flow characteristics generated by hemisphere boulders in an open channel flume. Velocity and turbulence influenced the variation in swimming behaviour with respect to size, sex and parasite intensity. With increasing body length, fish swam further and more frequently between boulder regions. Larger guppies spent more time in the areas of high-velocity and low-turbulence regions beside the boulders, whereas smaller guppies frequented the low-velocity and high-turbulence regions directly behind the boulders. Male guppies selected the regions of low velocity, indicating possible reduced swimming ability owing to hydrodynamic drag imposed by their fins. With increasing Gyrodactylus turnbulli burden, fish spent more time in regions with moderate velocity and lowest turbulent kinetic energy which were the most spatially and temporally homogeneous in terms of velocity and turbulence. These findings highlight the importance of heterogeneous flow conditions in river channel design owing to the behavioural variability within a species in response to velocity and turbulence. PMID:24284893
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Stephenson, J F; van Oosterhout, C; Cable, J
2015-11-01
A common evolutionary response to predation pressure is increased investment in reproduction, ultimately resulting in a fast life history. Theory and comparative studies suggest that short-lived organisms invest less in defence against parasites than those that are longer lived (the pace of life hypothesis). Combining these tenets of evolutionary theory leads to the specific, untested prediction that within species, populations experiencing higher predation pressure invest less in defence against parasites. The Trinidadian guppy, Poecilia reticulata, presents an excellent opportunity to test this prediction: guppy populations in lower courses of rivers experience higher predation pressure, and as a consequence have evolved faster life histories, than those in upper courses. Data from a large-scale field survey showed that fish infected with Gyrodactylus parasites were of a lower body condition (quantified using the scaled mass index) than uninfected fish, but only in lower course populations. Although the evidence we present is correlational, it suggests that upper course guppies sustain lower fitness costs of infection, i.e. are more tolerant, than lower course guppies. The data are therefore consistent with the pace of life hypothesis of parasite defence allocation, and suggest that life-history traits mediate the indirect effect of predators on the parasites of their prey. © 2015 The Author(s).
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Murugan, Kadarkarai; Dinesh, Devakumar; Nataraj, Devaraj; Subramaniam, Jayapal; Amuthavalli, Pandiyan; Madhavan, Jagannathan; Rajasekar, Aruliah; Rajan, Mariappan; Thiruppathi, Kulandhaivel Palani; Kumar, Suresh; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni
2018-04-01
The control of filariasis vectors has been enhanced in several areas, but there are main challenges, including increasing resistance to insecticides and lack of cheap and eco-friendly products. The toxicity of iron (Fe 0 ) and iron oxide (Fe 2 O 3 ) nanoparticles has been scarcely investigated yet. We studied the larvicidal and pupicidal activity of Fe 0 and Fe 2 O 3 nanoparticles against Culex quinquefasciatus. Fe 0 and Fe 2 O 3 nanoparticles produced by green (using a Ficus natalensis aqueous extract) and chemical nanosynthesis, respectively, were analyzed by UV-Vis spectrophotometry, FT-IR spectroscopy, XRD analysis, SEM, and EDX assays. In larvicidal and pupicidal experiments on Cx. quinquefasciatus, LC 50 of Fe 0 nanoparticles ranged from 20.9 (I instar larvae) to 43.7 ppm (pupae) and from 4.5 (I) to 22.1 ppm (pupae) for Fe 2 O 3 nanoparticles synthesized chemically. Furthermore, the predation efficiency of the guppy fish, Poecilia reticulata, after a single treatment with sub-lethal doses of Fe 0 and Fe 2 O 3 nanoparticles was magnified. Overall, this work provides new insights about the toxicity of Fe 0 and Fe 2 O 3 nanoparticles against mosquito vectors; we suggested that green and chemical fabricated nano-iron may be considered to develop novel and effective pesticides.
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Cross-generational effects of sexual harassment on female fitness in the guppy.
Gasparini, Clelia; Devigili, Alessandro; Pilastro, Andrea
2012-02-01
Sexual harassment is a common outcome of sexual conflict over mating rate. A large number of studies have identified several direct costs to females of sexual harassment including energy expenditure and reduced foraging ability. However, the fitness consequences of sexual harassment for descendants have rarely been investigated. Here, we manipulated the level of sexual harassment and mating rate in two groups of female guppies, Poecilia reticulata, a live-bearing fish in which sexual conflict over mating rate is particularly pronounced. Each female was allowed to interact with three males for one day (low sexual harassment, LSH) or for eight days (high sexual harassment, HSH) during each breeding cycle throughout their life. Female lifetime fecundity did not differ between the groups, but we found a strong effect on offspring fitness. HSH females produced (1) daughters with smaller bodies and (2) sons with shorter gonopodia, which were less attractive to females and less successful in coercive matings than their LSH counterparts. Although these results may be influenced by the indirect effects of sex ratio differences between treatments, they suggest that sexual harassment and elevated mating rate can have negative cross-generational fitness effects and more profound evolutionary consequences than currently thought. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.
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Female social response to male sexual harassment in poeciliid fish: a comparison of six species.
Dadda, Marco
2015-01-01
Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment.
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Darden, Safi K; James, Richard; Ramnarine, Indar W; Croft, Darren P
2009-07-22
Across sexually reproducing species, males and females are in conflict over the control of reproduction. At the heart of this conflict in a number of taxa is male harassment of females for mating opportunities and female strategies to avoid this harassment. One neglected consequence that may result from sexual harassment is the disruption of important social associations. Here, we experimentally manipulate the degree of sexual harassment that wild female guppies (Poecilia reticulata) experience by establishing replicated, semi-natural pools with different population sex ratios. We quantify the effects of sexual harassment on female social structure and the development of social recognition among females. When exposed to sexual harassment, we found that females had more disparate social networks with limited repeated interactions when compared to females that did not experience male harassment. Furthermore, females that did not experience harassment developed social recognition with familiar individuals over an 8-day period, whereas females that experienced harassment did not, an effect we suggest is due to disruption of association patterns. These results show that social network structure and social recognition can be affected by sexual harassment, an effect that will be relevant across taxonomic groups and that we predict will have fitness consequences for females.
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Female social response to male sexual harassment in poeciliid fish: a comparison of six species
Dadda, Marco
2015-01-01
Sexual harassment is common among poeciliid fish. In some fishes, males show a high frequency of sneak copulation; such sexual activity is costly to the females in terms of foraging efficiency. In mosquitofish (Gambusia holbrooki), when males are present, the distance between females tends to decrease, and this behavior has been interpreted as an adaptive strategy to dilute the costs of male sexual activity. In this study, the tendency to reduce distance in the presence of a male has been investigated in females of six poeciliid species (Girardinus metallicus, Girardinus falcatus, G. holbrooki, Poecilia reticulata, Xiphophorus hellerii, and Xiphophorus mayae) that exhibit different male mating strategies and different levels of sexual activity. Results revealed large interspecific differences in the pattern of female aggregation. Females of species with a high frequency of sneak copulations tended to reduce their social distance in the presence of a male. By contrast, species that rely mainly on courtship showed little or no variation in social distance. The proportion of sneak copulations predicts the degree of variation in female social response, but the amount of total sexual activity does not, suggesting that the change in females' social distance when a male is present may indeed serve to reduce the costs of male sexual harassment. PMID:26483719
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Chronic nitrate enrichment decreases severity and induces protection against an infectious disease.
Smallbone, Willow; Cable, Jo; Maceda-Veiga, Alberto
2016-05-01
Excessive fertilisation is one of the most pernicious forms of global change resulting in eutrophication. It has major implications for disease control and the conservation of biodiversity. Yet, the direct link between nutrient enrichment and disease remains largely unexplored. Here, we present the first experimental evidence that chronic nitrate enrichment decreases severity and induces protection against an infectious disease. Specifically, this study shows that nitrate concentrations ranging between 50 and 250mgNO3(-)/l reduce Gyrodactylus turnbulli infection intensity in two populations of Trinidadian guppies Poecilia reticulata, and that the highest nitrate concentration can even clean the parasites from the fish. This added to the fact that host nitrate pre-exposure altered the fish epidermal structure and reduced parasite intensity, suggests that nitrate protected the host against the disease. Nitrate treatments also caused fish mortality. As we used ecologically-relevant nitrate concentrations, and guppies are top-consumers widely used for mosquito bio-control in tropical and often nutrient-enriched waters, our results can have major ecological and social implications. In conclusion, this study advocates reducing nitrate level including the legislative threshold to protect the aquatic biota, even though this may control an ectoparasitic disease. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Sex-dependent selection differentially shapes genetic variation on and off the guppy Y chromosome.
Postma, Erik; Spyrou, Nicolle; Rollins, Lee Ann; Brooks, Robert C
2011-08-01
Because selection is often sex-dependent, alleles can have positive effects on fitness in one sex and negative effects in the other, resulting in intralocus sexual conflict. Evolutionary theory predicts that intralocus sexual conflict can drive the evolution of sex limitation, sex-linkage, and sex chromosome differentiation. However, evidence that sex-dependent selection results in sex-linkage is limited. Here, we formally partition the contribution of Y-linked and non-Y-linked quantitative genetic variation in coloration, tail, and body size of male guppies (Poecilia reticulata)-traits previously implicated as sexually antagonistic. We show that these traits are strongly genetically correlated, both on and off the Y chromosome, but that these correlations differ in sign and magnitude between both parts of the genome. As predicted, variation in attractiveness was found to be associated with the Y-linked, rather than with the non-Y-linked component of genetic variation in male ornamentation. These findings show how the evolution of Y-linkage may be able to resolve sexual conflict. More generally, they provide unique insight into how sex-specific selection has the potential to differentially shape the genetic architecture of fitness traits across different parts of the genome. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.
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Rolshausen, Gregor; Phillip, Dawn A T; Beckles, Denise M; Akbari, Ali; Ghoshal, Subhasis; Hamilton, Patrick B; Tyler, Charles R; Scarlett, Alan G; Ramnarine, Indar; Bentzen, Paul; Hendry, Andrew P
2015-01-01
The ability of populations to rapidly adapt to new environments will determine their future in an increasingly human-modified world. Although meta-analyses do frequently uncover signatures of local adaptation, they also reveal many exceptions. We suggest that particular constraints on local adaptation might arise when organisms are exposed to novel stressors, such as anthropogenic pollution. To inform this possibility, we studied the extent to which guppies (Poecilia reticulata) show local adaptation to oil pollution in southern Trinidad. Neutral genetic markers revealed that paired populations in oil-polluted versus not-polluted habitats diverged independently in two different watersheds. Morphometrics revealed some divergence (particularly in head shape) between these environments, some of which was parallel between rivers. Reciprocal transplant experiments in nature, however, found little evidence of local adaptation based on survival and growth. Moreover, subsequent laboratory experiments showed that the two populations from oil-polluted sites showed only weak local adaptation even when compared to guppies from oil-free northern Trinidad. We conclude that guppies show little local adaptation to oil pollution, which might result from the challenges associated with adaptation to particularly stressful environments. It might also reflect genetic drift owing to small population sizes and/or high gene flow between environments. PMID:26495039
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Eco-evolutionary effects on population recovery following catastrophic disturbance
Weese, Dylan J; Schwartz, Amy K; Bentzen, Paul; Hendry, Andrew P; Kinnison, Michael T
2011-01-01
Fine-scale genetic diversity and contemporary evolution can theoretically influence ecological dynamics in the wild. Such eco-evolutionary effects might be particularly relevant to the persistence of populations facing acute or chronic environmental change. However, experimental data on wild populations is currently lacking to support this notion. One way that ongoing evolution might influence the dynamics of threatened populations is through the role that selection plays in mediating the ‘rescue effect’, the ability of migrants to contribute to the recovery of populations facing local disturbance and decline. Here, we combine experiments with natural catastrophic events to show that ongoing evolution is a major determinant of migrant contributions to population recovery in Trinidadian guppies (Poecilia reticulata). These eco-evolutionary limits on migrant contributions appear to be mediated by the reinforcing effects of natural and sexual selection against migrants, despite the close geographic proximity of migrant sources. These findings show that ongoing adaptive evolution can be a double-edged sword for population persistence, maintaining local fitness at a cost to demographic risk. Our study further serves as a potent reminder that significant evolutionary and eco-evolutionary dynamics might be at play even where the phenotypic status quo is largely maintained generation to generation. PMID:25567978
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Fish responses to flow velocity and turbulence in relation to size, sex and parasite load.
Hockley, F A; Wilson, C A M E; Brew, A; Cable, J
2014-02-06
Riverine fish are subjected to heterogeneous flow velocities and turbulence and may use this to their advantage by selecting regions that balance energy expenditure for station holding while maximizing energy gain through feeding opportunities. This study investigated microhabitat selection by guppies Poecilia reticulata in terms of flow characteristics generated by hemisphere boulders in an open channel flume. Velocity and turbulence influenced the variation in swimming behaviour with respect to size, sex and parasite intensity. With increasing body length, fish swam further and more frequently between boulder regions. Larger guppies spent more time in the areas of high-velocity and low-turbulence regions beside the boulders, whereas smaller guppies frequented the low-velocity and high-turbulence regions directly behind the boulders. Male guppies selected the regions of low velocity, indicating possible reduced swimming ability owing to hydrodynamic drag imposed by their fins. With increasing Gyrodactylus turnbulli burden, fish spent more time in regions with moderate velocity and lowest turbulent kinetic energy which were the most spatially and temporally homogeneous in terms of velocity and turbulence. These findings highlight the importance of heterogeneous flow conditions in river channel design owing to the behavioural variability within a species in response to velocity and turbulence.
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Tobler, Michael; Schlupp, Ingo; Heubel, Katja U; Riesch, Rüdiger; de León, Francisco J García; Giere, Olav; Plath, Martin
2006-12-01
Most eucaryotic organisms classified as living in an extreme habitat are invertebrates. Here we report of a fish living in a Mexican cave (Cueva del Azufre) that is rich in highly toxic H(2)S. We compared the water chemistry and fish communities of the cave and several nearby surface streams. Our study revealed high concentrations of H(2)S in the cave and its outflow (El Azufre). The concentrations of H(2)S reach more than 300 muM inside the cave, which are acutely toxic for most fishes. In both sulfidic habitats, the diversity of fishes was heavily reduced, and Poecilia mexicana was the dominant species indicating that the presence of H(2)S has an all-or-none effect, permitting only few species to survive in sulfidic habitats. Compared to habitats without H(2)S, P. mexicana from the cave and the outflow have a significantly lower body condition. Although there are microhabitats with varying concentrations of H(2)S within the cave, we could not find a higher fish density in areas with lower concentrations of H(2)S. We discuss that P. mexicana is one of the few extremophile vertebrates. Our study supports the idea that extreme habitats lead to an impoverished species diversity.
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The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth
Kotrschal, Alexander; Corral‐Lopez, Alberto; Szidat, Sönke; Kolm, Niclas
2015-01-01
One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large‐ and small‐brained individuals. Instead, we found that large‐brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system. PMID:26420573
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Stabilizing selection on sperm number revealed by artificial selection and experimental evolution.
Cattelan, Silvia; Di Nisio, Andrea; Pilastro, Andrea
2018-03-01
Sperm competition is taxonomically widespread in animals and is usually associated with large sperm production, being the number of sperm in the competing pool the prime predictor of fertilization success. Despite the strong postcopulatory selection acting directionally on sperm production, its genetic variance is often very high. This can be explained by trade-offs between sperm production and traits associated with mate acquisition or survival, that may contribute to generate an overall stabilizing selection. To investigate this hypothesis, we first artificially selected male guppies (Poecilia reticulata) for high and low sperm production for three generations, while simultaneously removing sexual selection. Then, we interrupted artificial selection and restored sexual selection. Sperm production responded to divergent selection in one generation, and when we restored sexual selection, both high and low lines converged back to the mean sperm production of the original population within two generations, indicating that sperm number is subject to strong stabilizing total sexual selection (i.e., selection acting simultaneously on all traits associated with reproductive success). We discuss the possible mechanisms responsible for the maintenance of high genetic variability in sperm production despite strong selection acting on it. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.
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Developmental plasticity in vision and behavior may help guppies overcome increased turbidity.
Ehlman, Sean M; Sandkam, Benjamin A; Breden, Felix; Sih, Andrew
2015-12-01
Increasing turbidity in streams and rivers near human activity is cause for environmental concern, as the ability of aquatic organisms to use visual information declines. To investigate how some organisms might be able to developmentally compensate for increasing turbidity, we reared guppies (Poecilia reticulata) in either clear or turbid water. We assessed the effects of developmental treatments on adult behavior and aspects of the visual system by testing fish from both developmental treatments in turbid and clear water. We found a strong interactive effect of rearing and assay conditions: fish reared in clear water tended to decrease activity in turbid water, whereas fish reared in turbid water tended to increase activity in turbid water. Guppies from all treatments decreased activity when exposed to a predator. To measure plasticity in the visual system, we quantified treatment differences in opsin gene expression of individuals. We detected a shift from mid-wave-sensitive opsins to long wave-sensitive opsins for guppies reared in turbid water. Since long-wavelength sensitivity is important in motion detection, this shift likely allows guppies to salvage motion-detecting abilities when visual information is obscured in turbid water. Our results demonstrate the importance of developmental plasticity in responses of organisms to rapidly changing environments.
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Kotrschal, Alexander; Rogell, Björn; Bundsen, Andreas; Svensson, Beatrice; Zajitschek, Susanne; Brännström, Ioana; Immler, Simone; Maklakov, Alexei A; Kolm, Niclas
2013-01-21
The large variation in brain size that exists in the animal kingdom has been suggested to have evolved through the balance between selective advantages of greater cognitive ability and the prohibitively high energy demands of a larger brain (the "expensive-tissue hypothesis"). Despite over a century of research on the evolution of brain size, empirical support for the trade-off between cognitive ability and energetic costs is based exclusively on correlative evidence, and the theory remains controversial. Here we provide experimental evidence for costs and benefits of increased brain size. We used artificial selection for large and small brain size relative to body size in a live-bearing fish, the guppy (Poecilia reticulata), and found that relative brain size evolved rapidly in response to divergent selection in both sexes. Large-brained females outperformed small-brained females in a numerical learning assay designed to test cognitive ability. Moreover, large-brained lines, especially males, developed smaller guts, as predicted by the expensive-tissue hypothesis, and produced fewer offspring. We propose that the evolution of brain size is mediated by a functional trade-off between increased cognitive ability and reproductive performance and discuss the implications of these findings for vertebrate brain evolution. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Labonne, Jacques; Hendry, Andrew P
2010-07-01
The standard predictions of ecological speciation might be nuanced by the interaction between natural and sexual selection. We investigated this hypothesis with an individual-based model tailored to the biology of guppies (Poecilia reticulata). We specifically modeled the situation where a high-predation population below a waterfall colonizes a low-predation population above a waterfall. Focusing on the evolution of male color, we confirm that divergent selection causes the appreciable evolution of male color within 20 generations. The rate and magnitude of this divergence were reduced when dispersal rates were high and when female choice did not differ between environments. Adaptive divergence was always coupled to the evolution of two reproductive barriers: viability selection against immigrants and hybrids. Different types of sexual selection, however, led to contrasting results for another potential reproductive barrier: mating success of immigrants. In some cases, the effects of natural and sexual selection offset each other, leading to no overall reproductive isolation despite strong adaptive divergence. Sexual selection acting through female choice can thus strongly modify the effects of divergent natural selection and thereby alter the standard predictions of ecological speciation. We also found that under no circumstances did divergent selection cause appreciable divergence in neutral genetic markers.
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Getting into hot water: sick guppies frequent warmer thermal conditions.
Mohammed, Ryan S; Reynolds, Michael; James, Joanna; Williams, Chris; Mohammed, Azad; Ramsubhag, Adesh; van Oosterhout, Cock; Cable, Jo
2016-07-01
Ectotherms depend on the environmental temperature for thermoregulation and exploit thermal regimes that optimise physiological functioning. They may also frequent warmer conditions to up-regulate their immune response against parasite infection and/or impede parasite development. This adaptive response, known as 'behavioural fever', has been documented in various taxa including insects, reptiles and fish, but only in response to endoparasite infections. Here, a choice chamber experiment was used to investigate the thermal preferences of a tropical freshwater fish, the Trinidadian guppy (Poecilia reticulata), when infected with a common helminth ectoparasite Gyrodactylus turnbulli, in female-only and mixed-sex shoals. The temperature tolerance of G. turnbulli was also investigated by monitoring parasite population trajectories on guppies maintained at a continuous 18, 24 or 32 °C. Regardless of shoal composition, infected fish frequented the 32 °C choice chamber more often than when uninfected, significantly increasing their mean temperature preference. Parasites maintained continuously at 32 °C decreased to extinction within 3 days, whereas mean parasite abundance increased on hosts incubated at 18 and 24 °C. We show for the first time that gyrodactylid-infected fish have a preference for warmer waters and speculate that sick fish exploit the upper thermal tolerances of their parasites to self medicate.
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Ugalde, Diana; Gómez, Patricia; Simões, Nuno
2015-01-19
Marine sponges usually constitute the most diverse group of the benthic community in coral reefs. Although they are reasonably well studied at the northern Gulf of Mexico (GMx), the southern GMx is poorly known and lacks records from many major reef systems that lie off the Mexican coast. The present taxonomic study is the first sponge account from Alacranes reef, the largest coral reef system in the GMx, and from the shallow reef banks of Sisal, both in the northwest Yucatan Peninsula. The 19 species herein described represent the first sponge fauna records from these reefs. Among these, seven species represent new record for GMx: Erylus formosus, Cliona flavifodina, Spirastrella aff. mollis, Strongylacidon bermuda, Topsentia bahamensis, Agelas tubulata and Chelonaplysilla aff. erecta. Twelve species are new records for the Southern GMx: Erylus trisphaerus, Cliona amplicavata, Chondrilla caribensis, Halichondria lutea, Hymeniacidon caerulea, Axinella corrugata, Dragmacidon reticulatum, Chalinula molitba, Amphimedon caribica, A. complanata, Hyatella cavernosa and Dysidea variabilis. Additionally, a redescription of Erylus trisphaerus is presented which had not been reviewed since its original description in 1953 off Western Florida, except that it was listed for north La Habana, Cuba.
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Lee, J; Hymowitz, T
2001-11-01
Phylogenetic relationships among 13 genera of the subtribe Glycininae, two genera of the allied subtribe Diocleinae that were included within Glycininae by Polhill, and two genera of the subtribe Erythrininae as outgroups were inferred from chloroplast DNA rps16 intron sequence variation. Pairwise sequence divergence values ranged from identity between Teramnus mollis and T. micans and between T. flexilis and T. labialis to 7.89% between Pueraria wallichii and Pseudeminia comosa across all accessions. Phylogenies estimated using parsimony and neighbor-joining methods revealed that (1) Glycininae is monophyletic if Pachyrhizus and Calopogonium (both Diocleinae) are included within Glycininae; (2) the genus Teramnus is closely related to Glycine, and Amphicarpaea showed a sister relationship to the clade comprising Teramnus and Glycine; (3) the expanded Glycininae including two genera of Diocleinae is divided into three branches, temporarily named I (comprising the rest of the examined taxa), II (Pueraria wallichii), and III (Mastersia), but their relationships are equivocal; and (4) the genus Pueraria, regarded as a closely related genus to Glycine, is not monophyletic and should be divided into at least four genera (a hypothesis supported previously by Lackey).
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Municipal mortality due to thyroid cancer in Spain
Lope, Virginia; Pollán, Marina; Pérez-Gómez, Beatriz; Aragonés, Nuria; Ramis, Rebeca; Gómez-Barroso, Diana; López-Abente, Gonzalo
2006-01-01
Background Thyroid cancer is a tumor with a low but growing incidence in Spain. This study sought to depict its spatial municipal mortality pattern, using the classic model proposed by Besag, York and Mollié. Methods It was possible to compile and ascertain the posterior distribution of relative risk on the basis of a single Bayesian spatial model covering all of Spain's 8077 municipal areas. Maps were plotted depicting standardized mortality ratios, smoothed relative risk (RR) estimates, and the posterior probability that RR > 1. Results From 1989 to 1998 a total of 2,538 thyroid cancer deaths were registered in 1,041 municipalities. The highest relative risks were mostly situated in the Canary Islands, the province of Lugo, the east of La Coruña (Corunna) and western areas of Asturias and Orense. Conclusion The observed mortality pattern coincides with areas in Spain where goiter has been declared endemic. The higher frequency in these same areas of undifferentiated, more aggressive carcinomas could be reflected in the mortality figures. Other unknown genetic or environmental factors could also play a role in the etiology of this tumor. PMID:17173668
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Tong, Lidan; Guo, Lixin; Lv, Xiaojun; Li, Yu
2017-01-01
Three-dimensional quantitative structure-activity relationship (3D-QSAR) models were established by comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Experimental toxicity data in Poecilia reticulata (pLC 50 ) and physico-chemical properties for 12 polychlorinated phenols were used as dependent and as independent variables, respectively. Among the 12 polychlorinated phenols, nine were randomly selected and used as a training set to construct the 3D-QSAR models through the SYBYL-X software to predict the pLC 50 values of the remaining 8 polychlorinated phenols congeners, and the other three polychlorinated phenols were used as a test set to evaluate the 3D-QSAR models (the training set and test set were arranged randomly, shuffled 60 times). Pentachlorophenol (PCP), which is the most toxic among the 20 polychlorinated phenols used in this experiment, was selected as an example for modification using contour maps produced using the established 3D-QSAR models. The aim was to decrease its toxicity and bioconcentration, increase its biodegradation, and maintain or better its effectiveness as a pesticide. The 3D-QSAR models were robust and had good predictive abilities with cross-validation correlation coefficients (q 2 ) of 0.858-0.992 (>0.5), correlation coefficients (r 2 ) of 0.966-1.000 (>0.9), and standard errors of prediction (SEP) of 0.004-0.159. CoMFA showed that the toxicity of the polychlorinated phenols arose mainly from electrostatic (42.7-66.7%) and steric (33.3-7.3%) contributions. By comparison, CoMSIA showed that the toxicity of polychlorinated phenols was dominated by electrostatic (57.5-76.9%) and hydrophobic (19.8-25.7%) contributions, with lesser contributions from the steric (0.7-1.0%) hydrogen bond donor (0.1-20.3%), and hydrogen bond acceptor (0-0.9%). 3D-QSAR electrostatic contour maps were used to modify PCP and design 11 new compounds with lower toxicity. The effectiveness of each of
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Seng, E K; Fang, Q; Lam, T J; Sin, Y M
2004-06-15
A rapid, sensitive and highly specific detection method for Aquareovirus based on reverse-transcription polymerase chain reaction (RT-PCR) was developed. Based on multiple sequence alignment of the cloned sequences of a local isolates, the Threadfin reovirus (TFV) and Guppy reovirus (GPV) with Grass carp reovirus (GCRV), a pair of degenerate primers was selected carefully and synthesized. Using this primer combination, only one specific product, approximately 450 bp in length was obtained when RT-PCR was carried out using the genomic double-stranded RNA (dsRNA) of TFV, GPV and GCRV. Similar results were also obtained when Chum salmon reovirus (CSRV) and Striped bass reovirus (SBRV) dsRNA were used as templates. No products were observed when nucleic acids other than the dsRNA of the aquareoviruses described above were used as RT-PCR templates. This technique could detect not only TFV but also GPV and GCRV in low titer virus-infected cell cultured cells. Furthermore, this method has also been shown to be able to diagnose GPV-infected guppy (Poecilia reticulata) that exhibit clinical symptoms as well as GPV-carrier guppy. Collectively, these results showed that the RT-PCR amplification method using specific degenerate primers described below is very useful for rapid and accurate detection of a variety of aquareovirus strains isolated from different host species and origin.
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Santos, Danyelle K. F.; Resende, Ana H. M.; de Almeida, Darne G.; Soares da Silva, Rita de Cássia F.; Rufino, Raquel D.; Luna, Juliana M.; Banat, Ibrahim M.; Sarubbo, Leonie A.
2017-01-01
The aim of the present study was to investigate the potential application of the biosurfactant from Candida lipolytica grown in low-cost substrates, which has previously been produced and characterized under optimized conditions as an adjunct material to enhance the remediation processes of hydrophobic pollutants and heavy metals generated by the oil industry and propose the formulation of a safe and stable remediation agent. In tests carried out with seawater, the crude biosurfactant demonstrated 80% oil spreading efficiency. The dispersion rate was 50% for the biosurfactant at a concentration twice that of the CMC. The biosurfactant removed 70% of motor oil from contaminated cotton cloth in detergency tests. The crude biosurfactant also removed 30–40% of Cu and Pb from standard sand, while the isolated biosurfactant removed ~30% of the heavy metals. The conductivity of solutions containing Cd and Pb was sharply reduced after biosurfactants' addition. A product was prepared through adding 0.2% potassium sorbate as preservative and tested over 120 days. The formulated biosurfactant was analyzed for emulsification and surface tension under different pH values, temperatures, and salt concentrations and tested for toxicity against the fish Poecilia vivipara. The results showed that the formulation had no toxicity and did not cause significant changes in the tensoactive capacity of the biomolecule while maintaining activity demonstrating suitability for potential future commercial product formulation. PMID:28507538
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Kin assortment in juvenile shoals in wild guppy populations.
Piyapong, C; Butlin, R K; Faria, J J; Scruton, K J; Wang, J; Krause, J
2011-05-01
Grouping provides many potential benefits to individuals in terms of foraging and anti-predator protection. However, it has been suggested that individuals could gain additional benefits in terms of indirect fitness by grouping with kin. Surprisingly, the genetic composition of wild fish shoals and the importance of kin-associated shoaling remain poorly understood. The Trinidadian guppy (Poecilia reticulata) has life history traits that might promote kin structure of shoals such as internal fertilisation and small brood size in contrast to many other fish species. Even though previous studies did not find any indication of kin structure in shoals of adult guppies, it is possible that related juveniles remain together in shoals, partly because of lower mobility and because the advantages of kin association may change with age. Using 10 microsatellite markers, we conducted a genetic analysis on 40 shoals from four populations. Pair-wise relatedness was inferred using a modified version of the software package COLONY and permutation tests were conducted to test the hypothesis that kin occur together in juvenile shoals more often than expected by chance. The frequency of sib dyads among juveniles within shoals was significantly larger than that between shoals in two high predation populations but not in two low predation populations. This finding contributes to the understanding of factors underlying shoal composition and highlights the potential of recent methodological advances for detecting such relationships.
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High-predation habitats affect the social dynamics of collective exploration in a shoaling fish.
Ioannou, Christos C; Ramnarine, Indar W; Torney, Colin J
2017-05-01
Collective decisions play a major role in the benefits that animals gain from living in groups. Although the mechanisms of how groups collectively make decisions have been extensively researched, the response of within-group dynamics to ecological conditions is virtually unknown, despite adaptation to the environment being a cornerstone in biology. We investigate how within-group interactions during exploration of a novel environment are shaped by predation, a major influence on the behavior of prey species. We tested guppies ( Poecilia reticulata ) from rivers varying in predation risk under controlled laboratory conditions and find the first evidence of differences in group interactions between animals adapted to different levels of predation. Fish from high-predation habitats showed the strongest negative relationship between initiating movements and following others, which resulted in less variability in the total number of movements made between individuals. This relationship between initiating movements and following others was associated with differentiation into initiators and followers, which was only observed in fish from high-predation rivers. The differentiation occurred rapidly, as trials lasted 5 min, and was related to shoal cohesion, where more diverse groups from high-predation habitats were more cohesive. Our results show that even within a single species over a small geographical range, decision-making in a social context can vary with local ecological factors.
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Male sexual harassment alters female social behaviour towards other females.
Darden, Safi K; Watts, Lauren
2012-04-23
Male harassment of females to gain mating opportunities is a consequence of an evolutionary conflict of interest between the sexes over reproduction and is common among sexually reproducing species. Male Trinidadian guppies Poecilia reticulata spend a large proportion of their time harassing females for copulations and their presence in female social groups has been shown to disrupt female-female social networks and the propensity for females to develop social recognition based on familiarity. In this study, we investigate the behavioural mechanisms that may lead to this disruption of female sociality. Using two experiments, we test the hypothesis that male presence will directly affect social behaviours expressed by females towards other females in the population. In experiment one, we tested for an effect of male presence on female shoaling behaviour and found that, in the presence of a free-swimming male guppy, females spent shorter amounts of time with other females than when in the presence of a free-swimming female guppy. In experiment two, we tested for an effect of male presence on the incidence of aggressive behaviour among female guppies. When males were present in a shoal, females exhibited increased levels of overall aggression towards other females compared with female only shoals. Our work provides direct evidence that the presence of sexually harassing males alters female-female social behaviour, an effect that we expect will be recurrent across taxonomic groups.
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How predation shapes the social interaction rules of shoaling fish
Rosén, Emil; Ioannou, Christos C.; Rogell, Björn; Perna, Andrea; Ramnarine, Indar W.; Kolm, Niclas
2017-01-01
Predation is thought to shape the macroscopic properties of animal groups, making moving groups more cohesive and coordinated. Precisely how predation has shaped individuals' fine-scale social interactions in natural populations, however, is unknown. Using high-resolution tracking data of shoaling fish (Poecilia reticulata) from populations differing in natural predation pressure, we show how predation adapts individuals' social interaction rules. Fish originating from high predation environments formed larger, more cohesive, but not more polarized groups than fish from low predation environments. Using a new approach to detect the discrete points in time when individuals decide to update their movements based on the available social cues, we determine how these collective properties emerge from individuals' microscopic social interactions. We first confirm predictions that predation shapes the attraction–repulsion dynamic of these fish, reducing the critical distance at which neighbours move apart, or come back together. While we find strong evidence that fish align with their near neighbours, we do not find that predation shapes the strength or likelihood of these alignment tendencies. We also find that predation sharpens individuals' acceleration and deceleration responses, implying key perceptual and energetic differences associated with how individuals move in different predation regimes. Our results reveal how predation can shape the social interactions of individuals in groups, ultimately driving differences in groups' collective behaviour. PMID:28855361
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Brooks, R; Endler, J A
2001-08-01
Variation among females in mate choice may influence evolution by sexual selection. The genetic basis of this variation is of interest because the elaboration of mating preferences requires additive genetic variation in these traits. Here we measure the repeatability and heritability of two components of female choosiness (responsiveness and discrimination) and of female preference functions for the multiple ornaments borne by male guppies (Poecilia reticulata). We show that there is significant repeatable variation in both components of choosiness and in some preference functions but not in others. There appear to be several male ornaments that females find uniformly attractive and others for which females differ in preference. One consequence is that there is no universally attractive male phenotype. Only responsiveness shows significant additive genetic variation. Variation in responsiveness appears to mask variation in discrimination and some preference functions and may be the most biologically relevant source of phenotypic and genetic variation in mate-choice behavior. To test the potential evolutionary importance of the phenotypic variation in mate choice that we report, we estimated the opportunity for and the intensity of sexual selection under models of mate choice that excluded and that incorporated individual female variation. We then compared these estimates with estimates based on measured mating success. Incorporating individual variation in mate choice generally did not predict the outcome of sexual selection any better than models that ignored such variation.
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Evolution of brain region volumes during artificial selection for relative brain size.
Kotrschal, Alexander; Zeng, Hong-Li; van der Bijl, Wouter; Öhman-Mägi, Caroline; Kotrschal, Kurt; Pelckmans, Kristiaan; Kolm, Niclas
2017-12-01
The vertebrate brain shows an extremely conserved layout across taxa. Still, the relative sizes of separate brain regions vary markedly between species. One interesting pattern is that larger brains seem associated with increased relative sizes only of certain brain regions, for instance telencephalon and cerebellum. Till now, the evolutionary association between separate brain regions and overall brain size is based on comparative evidence and remains experimentally untested. Here, we test the evolutionary response of brain regions to directional selection on brain size in guppies (Poecilia reticulata) selected for large and small relative brain size. In these animals, artificial selection led to a fast response in relative brain size, while body size remained unchanged. We use microcomputer tomography to investigate how the volumes of 11 main brain regions respond to selection for larger versus smaller brains. We found no differences in relative brain region volumes between large- and small-brained animals and only minor sex-specific variation. Also, selection did not change allometric scaling between brain and brain region sizes. Our results suggest that brain regions respond similarly to strong directional selection on relative brain size, which indicates that brain anatomy variation in contemporary species most likely stem from direct selection on key regions. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
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Both Geography and Ecology Contribute to Mating Isolation in Guppies
Schwartz, Amy K.; Weese, Dylan J.; Bentzen, Paul; Kinnison, Michael T.; Hendry, Andrew P.
2010-01-01
Local adaptation to different environments can promote mating isolation – either as an incidental by-product of trait divergence, or as a result of selection to avoid maladaptive mating. Numerous recent empirical examples point to the common influence of divergent natural selection on speciation based largely on evidence of strong pre-mating isolation between populations from different habitat types. Accumulating evidence for natural selection's influence on speciation is therefore no longer a challenge. The difficulty, rather, is in determining the mechanisms involved in the progress of adaptive divergence to speciation once barriers to gene flow are already present. Here, we present results of both laboratory and field experiments with Trinidadian guppies (Poecilia reticulata) from different environments, who do not show complete reproductive isolation despite adaptive divergence. We investigate patterns of mating isolation between populations that do and do not exchange migrants and show evidence for both by-product and reinforcement mechanisms depending on female ecology. Specifically, low-predation females discriminate against all high-predation males thus implying a by-product mechanism, whereas high-predation females only discriminate against low-predation males from further upstream in the same river, implying selection to avoid maladaptive mating. Our study thus confirms that mechanisms of adaptive speciation are not necessarily mutually exclusive and uncovers the complex ecology-geography interactions that underlie the evolution of mating isolation in nature. PMID:21179541
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Petasiger dietz, 1909 (Trematoda: Echinostomatidae) in birds and mollusks from Brazil.
Pinto, Hudson Alves; Mahecha, Germán Arturo Bohórquez; de Melo, Alan Lane
2013-01-01
Species of Petasiger Dietz, 1909 are intestinal trematodes of aquatic birds. Despite the diversity of described species in Europe and North America, only two South American species are known and no species have been previously reported in birds from Brazil. During a study of helminths recovered from the Least Grebe, Tachybaptus dominicus (Linnaeus, 1766), from the state of Minas Gerais, Brazil, adult trematodes identified as Petasiger novemdecim Lutz, 1928 were found. The prevalence of infection was 55% (5/9), and the mean intensity of infection was 8 (1-32) parasites. Additionally, Biomphalaria straminea (Dunker, 1848) and Biomphalaria tenagophila (d'Orbigny, 1835) obtained from aquatic collections in the same state were found to harbor two species of echinostome cercariae of the Magnacauda group. These cercariae developed into metacercariae in experimentally infected Poecilia reticulata Peters, 1859. Attempts to obtain adult parasites in vertebrate host models (mice, chickens, ducks and canaries) were unsuccessful. The present study is the first report of Petasiger in Brazilian birds and the first morphological description of larvae of these parasites in Brazilian mollusks. Taxonomic aspects related to South American species of Petasiger are discussed. It is suggested that, based on significant morphological differences observed in larval stages (i.e., larval dimensions) and adult parasites (i.e., disposition of the testes), Petasiger caribbensis Nassi, 1980 should be reconsidered as a distinct species from P. novemdecim.
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Ovarian fluid of receptive females enhances sperm velocity
NASA Astrophysics Data System (ADS)
Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea
2012-05-01
The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy ( Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites.
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Using Hidden Markov Models to characterise intermittent social behaviour in fish shoals
NASA Astrophysics Data System (ADS)
Bode, Nikolai W. F.; Seitz, Michael J.
2018-02-01
The movement of animals in groups is widespread in nature. Understanding this phenomenon presents an important problem in ecology with many applications that range from conservation to robotics. Underlying all group movements are interactions between individual animals and it is therefore crucial to understand the mechanisms of this social behaviour. To date, despite promising methodological developments, there are few applications to data of practical statistical techniques that inferentially investigate the extent and nature of social interactions in group movement. We address this gap by demonstrating the usefulness of a Hidden Markov Model approach to characterise individual-level social movement in published trajectory data on three-spined stickleback shoals ( Gasterosteus aculeatus) and novel data on guppy shoals ( Poecilia reticulata). With these models, we formally test for speed-mediated social interactions and verify that they are present. We further characterise this inferred social behaviour and find that despite the substantial shoal-level differences in movement dynamics between species, it is qualitatively similar in guppies and sticklebacks. It is intermittent, occurring in varying numbers of individuals at different time points. The speeds of interacting fish follow a bimodal distribution, indicating that they are either stationary or move at a preferred mean speed, and social fish with more social neighbours move at higher speeds, on average. Our findings and methodology present steps towards characterising social behaviour in animal groups.
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Russell, B M; Wang, J; Williams, Y; Hearnden, M N; Kay, B H
2001-06-01
The ability of 2 freshwater fishes, eastern rainbow fish Melanotaenia splendida splendida and fly-specked hardyhead Craterocephalus stercusmuscarum stercusmuscarum, native to North Queensland to prey on immature Aedes aegypti was evaluated under laboratory conditions. The predation efficiency of the 2 species was compared to the exotic guppy, Poecilia reticulata, which is commonly used as a biological control agent of mosquito larvae. Of the 3 fish species tested, M. s. splendida was shown to be the most promising agent for the biological control of Ae. aegypti that breed in wells. Melanotaenia s. splendida consumed significantly greater numbers of immature Ae. aegypti than P. reticulata, irrespective of developmental stage or light conditions. Unlike C s. stercusmuscarum, M. s. splendida could be handled, transported, and kept in captivity for extended periods with negligible mortality. However, M. s. splendida was also an efficient predator of Litoria caerulea tadpoles, a species of native frog found in wells during the dry season. This result may limit the usefulness of M. s. splendida as a biological control agent of well-breeding Ae. aegypti and suggests that predacious copepods, Mesocyclops spp., are more suitable. However, the use of M. s. splendida as a mosquito control agent in containers that are unlikely to support frog populations (e.g., aquaculture tanks and drinking troughs) should be given serious consideration.
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The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth.
Kotrschal, Alexander; Corral-Lopez, Alberto; Szidat, Sönke; Kolm, Niclas
2015-11-01
One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large- and small-brained individuals. Instead, we found that large-brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system. © 2015 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
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Plath, Martin; Pfenninger, Markus; Lerp, Hannes; Riesch, Rüdiger; Eschenbrenner, Christoph; Slattery, Patrick A; Bierbach, David; Herrmann, Nina; Schulte, Matthias; Arias-Rodriguez, Lenin; Rimber Indy, Jeane; Passow, Courtney; Tobler, Michael
2013-09-01
We investigated mechanisms of reproductive isolation in livebearing fishes (genus Poecilia) inhabiting sulfidic and nonsulfidic habitats in three replicate river drainages. Although sulfide spring fish convergently evolved divergent phenotypes, it was unclear if mechanisms of reproductive isolation also evolved convergently. Using microsatellites, we found strongly reduced gene flow between adjacent populations from different habitat types, suggesting that local adaptation to sulfidic habitats repeatedly caused the emergence of reproductive isolation. Reciprocal translocation experiments indicate strong selection against immigrants into sulfidic waters, but also variation among drainages in the strength of selection against immigrants into nonsulfidic waters. Mate choice experiments revealed the evolution of assortative mating preferences in females from nonsulfidic but not from sulfidic habitats. The inferred strength of sexual selection against immigrants (RI(s)) was negatively correlated with the strength of natural selection (RI(m)), a pattern that could be attributed to reinforcement, whereby natural selection strengthens behavioral isolation due to reduced hybrid fitness. Overall, reproductive isolation and genetic differentiation appear to be replicated and direct consequences of local adaptation to sulfide spring environments, but the relative contributions of different mechanisms of reproductive isolation vary across these evolutionarily independent replicates, highlighting both convergent and nonconvergent evolutionary trajectories of populations in each drainage. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
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Quantitative genetic insights into the coevolutionary dynamics of male and female genitalia
Evans, Jonathan P.; van Lieshout, Emile; Gasparini, Clelia
2013-01-01
The spectacular variability that typically characterizes male genital traits has largely been attributed to the role of sexual selection. Among the evolutionary mechanisms proposed to account for this diversity, two processes in particular have generated considerable interest. On the one hand, females may exploit postcopulatory mechanisms of selection to favour males with preferred genital traits (cryptic female choice; CFC), while on the other hand females may evolve structures or behaviours that mitigate the direct costs imposed by male genitalia (sexual conflict; SC). A critical but rarely explored assumption underlying both processes is that male and female reproductive traits coevolve, either via the classic Fisherian model of preference-trait coevolution (CFC) or through sexually antagonistic selection (SC). Here, we provide evidence for this prediction in the guppy (Poecilia reticulata), a polyandrous livebearing fish in which males transfer sperm internally to females via consensual and forced matings. Our results from a paternal half-sibling breeding design reveal substantial levels of additive genetic variation underlying male genital size and morphology—two traits known to predict mating success during non-consensual matings. Our subsequent finding that physically interacting female genital traits exhibit corresponding levels of genetic (co)variation reveals the potential intersexual coevolutionary dynamics of male and female genitalia, thereby fulfilling a fundamental assumption underlying CFC and SC theory. PMID:23720546
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Dynamic eye colour as an honest signal of aggression.
Heathcote, Robert J P; Darden, Safi K; Troscianko, Jolyon; Lawson, Michael R M; Brown, Antony M; Laker, Philippa R; Naisbett-Jones, Lewis C; MacGregor, Hannah E A; Ramnarine, Indar; Croft, Darren P
2018-06-04
Animal eyes are some of the most widely recognisable structures in nature. Due to their salience to predators and prey, most research has focused on how animals hide or camouflage their eyes [1]. However, across all vertebrate Classes, many species actually express brightly coloured or conspicuous eyes, suggesting they may have also evolved a signalling function. Nevertheless, perhaps due to the difficulty with experimentally manipulating eye appearance, very few species beyond humans [2] have been experimentally shown to use eyes as signals [3]. Using staged behavioural trials we show that Trinidadian guppies (Poecilia reticulata), which can rapidly change their iris colour, predominantly express conspicuous eye colouration when performing aggressive behaviours towards smaller conspecifics. Furthermore, using a novel, visually realistic robotic system to create a mismatch between signal and relative competitive ability, we show that eye colour is used to honestly signal aggressive motivation. Specifically, robotic 'cheats' (that is, smaller, less-competitive robotic fish that display aggressive eye colouration when defending a food patch) attracted greater food competition from larger real fish. Our study suggests that eye colour may be an under-appreciated aspect of signalling in animals, shows the utility of our biomimetic robotic system for investigating animal behaviour, and provides experimental evidence that socially mediated costs towards low-quality individuals may maintain the honesty of dynamic colour signals. Copyright © 2018 Elsevier Ltd. All rights reserved.
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How predation shapes the social interaction rules of shoaling fish.
Herbert-Read, James E; Rosén, Emil; Szorkovszky, Alex; Ioannou, Christos C; Rogell, Björn; Perna, Andrea; Ramnarine, Indar W; Kotrschal, Alexander; Kolm, Niclas; Krause, Jens; Sumpter, David J T
2017-08-30
Predation is thought to shape the macroscopic properties of animal groups, making moving groups more cohesive and coordinated. Precisely how predation has shaped individuals' fine-scale social interactions in natural populations, however, is unknown. Using high-resolution tracking data of shoaling fish ( Poecilia reticulata ) from populations differing in natural predation pressure, we show how predation adapts individuals' social interaction rules. Fish originating from high predation environments formed larger, more cohesive, but not more polarized groups than fish from low predation environments. Using a new approach to detect the discrete points in time when individuals decide to update their movements based on the available social cues, we determine how these collective properties emerge from individuals' microscopic social interactions. We first confirm predictions that predation shapes the attraction-repulsion dynamic of these fish, reducing the critical distance at which neighbours move apart, or come back together. While we find strong evidence that fish align with their near neighbours, we do not find that predation shapes the strength or likelihood of these alignment tendencies. We also find that predation sharpens individuals' acceleration and deceleration responses, implying key perceptual and energetic differences associated with how individuals move in different predation regimes. Our results reveal how predation can shape the social interactions of individuals in groups, ultimately driving differences in groups' collective behaviour. © 2017 The Authors.
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Shen, S C; Li, J S; Huang, M C
2014-06-02
Fourier series and an energy mapping method were used in this study to design a lens that produces a light pattern of multiple concentric circles (LPMCC) for a light-emitting diode (LED) fishing lamp. Fourier series were used to represent the light intensity distribution curve (LIDC) of the LPMCC light pattern. Energy mapping involves performing angular energy mapping based on the LIDCs of an LED light source and LPMCC to design a freeform lens. Type I and Type II LPMCC lenses were designed according to the phototaxis behavior of fish to create a LPMCC light pattern of interleaving light-dark zones that attracts fish shoals to stay in an area for a long period. The experimental results indicated that, in comparing the LIDCs of the Type I and II lenses with the respective simulation values, the normalized cross-correlation (NCC) value reached 96%. According to a 24-hour observation of the phototaxis of Poecilia reticulata to evaluate the effectiveness of the proposed light pattern to attract fish, when a fish shoal was habituated to a light source that emitted constant illumination light, it gradually moved away from the intense light zone and hovered around the junction of the light and dark zones. In the future, the design used in this study can be applied to LED fishing lamps to replace traditional fishing lamps.
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Host heterogeneity affects both parasite transmission to and fitness on subsequent hosts
Young, Kyle A.; Fox, Jordan; Jokela, Jukka
2017-01-01
Infectious disease dynamics depend on the speed, number and fitness of parasites transmitting from infected hosts (‘donors’) to parasite-naive ‘recipients’. Donor heterogeneity likely affects these three parameters, and may arise from variation between donors in traits including: (i) infection load, (ii) resistance, (iii) stage of infection, and (iv) previous experience of transmission. We used the Trinidadian guppy, Poecilia reticulata, and a directly transmitted monogenean ectoparasite, Gyrodactylus turnbulli, to experimentally explore how these sources of donor heterogeneity affect the three transmission parameters. We exposed parasite-naive recipients to donors (infected with a single parasite strain) differing in their infection traits, and found that donor infection traits had diverse and sometimes interactive effects on transmission. First, although transmission speed increased with donor infection load, the relationship was nonlinear. Second, while the number of parasites transmitted generally increased with donor infection load, more resistant donors transmitted more parasites, as did those with previous transmission experience. Finally, parasites transmitting from experienced donors exhibited lower population growth rates on recipients than those from inexperienced donors. Stage of infection had little effect on transmission parameters. These results suggest that a more holistic consideration of within-host processes will improve our understanding of between-host transmission and hence disease dynamics. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289260
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Variable environmental effects on a multicomponent sexually selected trait.
Cole, Gemma L; Endler, John A
2015-04-01
Multicomponent signals are made up of interacting elements that generate a functional signaling unit. The interactions between signal components and their effects on individual fitness are not well understood, and the effect of environment is even less so. It is usually assumed that color patterns appear the same in all light environments and that the effects of each color are additive. Using guppies, Poecilia reticulata, we investigated the effect of water color on the interactions between components of sexually selected male coloration. Through behavioral mate choice trials in four different water colors, we estimated the attractiveness of male color patterns, using multivariate fitness estimates and overall signal contrast. Our results show that females exhibit preferences that favor groups of colors rather than individual colors independently and that each environment favors different color combinations. We found that these effects are consistent with female guppies selecting entire color patterns on the basis of overall visual contrast. This suggests that both individuals and populations inhabiting different light environments will be subject to divergent, multivariate selection. Although the appearance of color patterns changes with light environment, achromatic components change little, suggesting that these could function in species recognition or other aspects of communication that must work across environments. Consequently, we predict different phylogenetic patterns between chromatic and achromatic signals within the same clades.
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Forced monogamy in a multiply mating species does not impede colonisation success.
Deacon, Amy E; Barbosa, Miguel; Magurran, Anne E
2014-06-12
The guppy (Poecilia reticulata) is a successful invasive species. It is also a species that mates multiply; previous studies have demonstrated that this strategy carries fitness benefits. Guppies are routinely introduced to tanks and troughs in regions outside their native range for mosquito-control purposes, and often spread beyond these initial confines into natural water bodies with negative ecological consequences. Here, using a mesocosm set up that resembles the containers into which single guppies are typically introduced for mosquito control, we ask whether singly-mated females are at a disadvantage, relative to multiply-mated females, when it comes to founding a population. Treatments were monitored for one year. A key finding was that mating history did not predict establishment success, which was 88% in both treatments. Furthermore, analysis of behavioural traits revealed that the descendants of singly-mated females retained antipredator behaviours, and that adult males showed no decrease in courtship vigour. Also, we detected no differences in behavioural variability between treatments. These results suggest that even when denied the option of multiple mating, singly-mated female guppies can produce viable populations, at least at the founder stage. This may prove to be a critical advantage in typical introduction scenarios where few individuals are released into enclosed water bodies before finding their way into natural ecosystems.
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NASA Astrophysics Data System (ADS)
Gharajehdaghipour, Tazarve; Roth, James D.; Fafard, Paul M.; Markham, John H.
2016-04-01
Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ15N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra.
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Linn, Charles E; Yee, Wee L; Sim, Sheina B; Cha, Dong H; Powell, Thomas H Q; Goughnour, Robert B; Feder, Jeffrey L
2012-11-01
The recent shift of Rhagoletis pomonella (Diptera: Tephritidae) from its native host downy hawthorn, Crataegus mollis, to introduced domesticated apple, Malus domestica, in the eastern United States is a model for sympatric host race formation. However, the fly is also present in the western United States, where it may have been introduced via infested apples within the last 60 years. In addition to apple, R. pomonella also infests two hawthorns in the West, one the native black hawthorn, C. douglasii, and the other the introduced English ornamental hawthorn, C. monogyna. Here, we test for behavioral evidence of host races in the western United States. through flight tunnel assays of western R. pomonella flies to host fruit volatile blends. We report that western apple, black hawthorn, and ornamental hawthorn flies showed significantly increased levels of upwind-directed flight to their respective natal compared to nonnatal fruit volatile blends, consistent with host race status. We discuss the implications of the behavioral results for the origin(s) of western R. pomonella, including the possibility that western apple flies were not introduced, but may represent a recent shift from local hawthorn fly populations. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
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Berdan, Emma L; Mazzoni, Camila J; Waurick, Isabelle; Roehr, Johannes T; Mayer, Frieder
2015-08-01
Understanding the genetics of speciation and the processes that drive it is a central goal of evolutionary biology. Grasshoppers of the Chorthippus species group differ strongly in calling song (and corresponding female preferences) but are exceedingly similar in other characteristics such as morphology. Here, we performed a population genomic scan on three Chorthippus species (Chorthippus biguttulus, C. mollis and C. brunneus) to gain insight into the genes and processes involved in divergence and speciation in this group. Using an RNA-seq approach, we examined functional variation between the species by calling SNPs for each of the three species pairs and using FST -based approaches to identify outliers. We found approximately 1% of SNPs in each comparison to be outliers. Between 37% and 40% of these outliers were nonsynonymous SNPs (as opposed to a global level of 17%) indicating that we recovered loci under selection. Among the outliers were several genes that may be involved in song production and hearing as well as genes involved in other traits such as food preferences and metabolism. Differences in food preferences between species were confirmed with a behavioural experiment. This indicates that multiple phenotypic differences implicating multiple evolutionary processes (sexual selection and natural selection) are present between the species. © 2015 John Wiley & Sons Ltd.
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Gharajehdaghipour, Tazarve; Roth, James D.; Fafard, Paul M.; Markham, John H.
2016-01-01
Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ15N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra. PMID:27045973
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Gharajehdaghipour, Tazarve; Roth, James D; Fafard, Paul M; Markham, John H
2016-04-05
Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ(15)N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra.
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Ruffinengo, Sergio; Eguaras, Martin; Floris, Ignazio; Faverin, Claudia; Bailac, Pedro; Ponzi, Marta
2005-06-01
The repellent and acaricidal effects of some essential oils from the most typical wild plant species of northern Patagonia, Argentina, on Varroa destructor Anderson & Trueman were evaluated using a complete exposure test. Honey bees, Apis mellifera L., and mites (five specimens of each per dish) were introduced in petri dishes having different oil concentrations (from 0.1 to 25 micro per cage). Survival of bees and mites was registered after 24, 48, and 72 h. An attraction/repellence test was performed using a wax tube impregnated with essential oil and another tube containing wax only. The lowest LD50 values for mites were registered for Acantholippia seriphioides (A. Gray) Mold. (1.27 microl per cage) and Schinus molle L. (2.65 microl per cage) after 24 h, and for Wedelia glauca (Ortega) O. Hoffm. ex Hicken (0.59 microl per cage) and A. seriphioides (1.09 microl per cage) after 72 h of treatment. The oil with the highest selectivity ratio (A. mellifera LD50/V. destructor LD50) was the one extracted from S. molle (>16). Oils of Lippia junelliana (Mold.) Troncoso, Minthostachys mollis (HBK) Grieseb., and Lippia turbinata Grieseb. mixed with wax had repellent properties. None of the oils tested had attractive effects on Varroa mites.
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59-year-old female with breathlessness.
Scatteia, Alessandra; De Garate, Estefania; Bucciarelli-Ducci, Chiara
2016-10-15
A 59-year-old female underwent an electrocardiogram (ECG) and echocardiographic screening. Her brother died at quite a young age of kidney failure. Resting ECG showed borderline voltage criteria for left ventricular hypertrophy (LVH), with marked widespread T-wave inversion. Echocardiogram was normal, but in consideration of exertional breathlessness and abnormal baseline ECG, she underwent a coronary angiogram, which showed unobstructed coronaries. She was then referred to have a cardiac MR (CMR) for further characterisation. CMR images were acquired with a 1.5 T scanner and the imaging protocol included Steady-State Free Precession (SSFP) cine images (Figure 1A) as well as late gadolinium enhancement (LGE) images in the long-axis and short-axis planes covering the whole left ventricle (Figure 1B). In addition, native and postcontrast T1 mapping (Modified Look-Locker (MOLLI)) images were acquired for further tissue characterisation (Figure 1C and D, respectively). What is the most likely diagnosis based on CMR findings? Anderson-Fabry's disease (AFD)Cardiac amyloidosisGenotype (+), phenotype (-) hypertrophic cardiomyopathy (HCM)Myocardial iron overloadNormal heart. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
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Vegetation of eastern Unalaska Island, Aleutian Islands, Alaska
Talbot, Stephen S.; Schofield, Wilfred B.; Talbot, Sandra L.; Daniëls, Fred J. A.
2010-01-01
Plant communities of Unalaska Island in the eastern Aleutian Islands of western Alaska, and their relationship to environmental variables, were studied using a combined Braun-Blanquet and multivariate approach. Seventy relevés represented the range of structural and compositional variation in the matrix of vegetation and landform zonation. Eleven major community types were distinguished within six physiognomic–ecological groups: I. Dry coastal meadows: Honckenya peploides beach meadow, Leymus mollis dune meadow. II. Mesic meadows: Athyrium filix-femina – Aconitum maximum meadow, Athyrium filix-femina – Calamagrostis nutkaensis meadow, Erigeron peregrinus – Thelypteris quelpaertensis meadow. III. Wet snowbed meadow: Carex nigricans snowbed meadow. IV. Heath: Linnaea borealis – Empetrum nigrum heath, Phyllodoce aleutica heath, Vaccinium uliginosum – Thamnolia vermicularis fellfield. V. Mire: Carex pluriflora – Plantago macrocarpa mire. VI. Deciduous shrub thicket: Salix barclayi – Athyrium filix-femina thicket. These were interpreted as a complex gradient primarily influenced by soil moisture, elevation, and pH. Phytogeographical and syntaxonomical analysis of the plant communities indicated that the dry coastal meadows, most of the heaths, and the mire vegetation belonged, respectively, to the widespread classes Honckenyo–Elymetea, Loiseleurio–Vaccinietea, and Scheuchzerio–Caricetea, characterized by their circumpolar and widespread species. Amphi-Beringian species were likely diagnostic of amphi-Beringian syntaxa, many of these yet to be described.
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Assessment of anti-oxidant activity of plant extracts using microbial test systems.
Oktyabrsky, O; Vysochina, G; Muzyka, N; Samoilova, Z; Kukushkina, T; Smirnova, G
2009-04-01
To evaluate the anti-oxidant properties of extracts from 20 medicinal herbs growing in western Siberia using microbial test systems and different in vitro methods. In vivo anti-oxidant activity of extracts was evaluated for their capacity to protect bacteria, Escherichia coli, against bacteriostatic and bactericidal effects of H(2)O(2) and menadione, and action on anti-oxidant gene expression. In vitro anti-oxidant activity has been examined by a number of methods including: the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(*))-scavenging assay, chelating activity and capacity to protect plasmid DNA against oxidative damage. In addition, total polyphenol content was determined. The extracts of Fragaria vesca, Rosa majalis, Pentaphylloides fruticosa, Alchemilla vulgaris and Pulmonaria mollis possessed the highest levels of anti-oxidant activity in vivo and in vitro. The protective properties were more closely related to the DPPH(*) radical-scavenging activity, tannin content and action on anti-oxidant gene expression than to other parameters. The extracts of medicinal plants may have anti-oxidant effects on bacteria simultaneously through several different pathways, including direct inhibition of reactive oxygen species, iron chelation and anti-oxidant genes induction. Using microbial test systems, we revealed herbs that may be used as potential sources of natural anti-oxidants.
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Ivrea mantle wedge and arc of the Western Alps (I): Geophysical evidence for the deep structure
NASA Astrophysics Data System (ADS)
Kissling, Edi; Schmid, Stefan M.; Diehl, Tobias
2017-04-01
The construction of five crustal-scale profiles across the Western Alps and the Ivrea mantle wedge integrates up-to-date geological and geophysical information and reveals important along strike changes in the overall structure of the crust of the Western Alpine arc (Schmid et al. 2017). The 3D crustal model of the Western Alps represented by these cross sections is based on recent P-velocity local earthquake tomography that compliments the previously existing wealth of geophysical information about lithosphere structure in the region. As part of Adria mantle lithosphere exhibiting strong upward bending toward the plate boundary along the inner arc of the Western Alps, the well-known Ivrea body plays a crucial role in our tectonic model. Until recently, however, the detailed 3D geometry of this key structure was only poorly constrained. In this study we present a review of the many seismic data in the region and we document the construction of our 3D lithosphere model by principles of multidisciplinary seismic tomography. Reference: Stefan M. Schmid, Edi Kissling, Douwe J.J. van Hinsbergen, Giancarlo Molli (2017). Ivrea mantle wedge and arc of the Western Alps (2): Kinematic evolution of the Alps-Apennines orogenic system. Abstract Volume EGU 2017.
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Parasite transmission in social interacting hosts: Monogenean epidemics in guppies
Johnson, Mirelle B.; Lafferty, Kevin D.; van Oosterhout, Cock; Cable, Joanne
2011-01-01
Background Infection incidence increases with the average number of contacts between susceptible and infected individuals. Contact rates are normally assumed to increase linearly with host density. However, social species seek out each other at low density and saturate their contact rates at high densities. Although predicting epidemic behaviour requires knowing how contact rates scale with host density, few empirical studies have investigated the effect of host density. Also, most theory assumes each host has an equal probability of transmitting parasites, even though individual parasite load and infection duration can vary. To our knowledge, the relative importance of characteristics of the primary infected host vs. the susceptible population has never been tested experimentally. Methodology/Principal Findings Here, we examine epidemics using a common ectoparasite, Gyrodactylus turnbulli infecting its guppy host (Poecilia reticulata). Hosts were maintained at different densities (3, 6, 12 and 24 fish in 40 L aquaria), and we monitored gyrodactylids both at a population and individual host level. Although parasite population size increased with host density, the probability of an epidemic did not. Epidemics were more likely when the primary infected fish had a high mean intensity and duration of infection. Epidemics only occurred if the primary infected host experienced more than 23 worm days. Female guppies contracted infections sooner than males, probably because females have a higher propensity for shoaling. Conclusions/Significance These findings suggest that in social hosts like guppies, the frequency of social contact largely governs disease epidemics independent of host density.
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Brask, Josefine B; Croft, Darren P; Thompson, Katharine; Dabelsteen, Torben; Darden, Safi K
2012-05-07
Male sexual harassment of females is common across sexually reproducing species and can result in fitness costs to females. We hypothesized that females can reduce unwanted male attention by constructing a social niche where their female associates are more sexually attractive than themselves, thus influencing the decision-making of males to their advantage. We tested this hypothesis in the Trinidadian guppy (Poecilia reticulata), a species with high levels of male sexual harassment. First, we confirmed that non-receptive females were harassed less when they were paired with a more sexually attractive (receptive) female than with another non-receptive female. We then found that, indeed, females exploit this as a strategy to reduce sexual harassment; non-receptive females actively preferred to associate with receptive over non-receptive females. Importantly, when given access only to chemosensory cues, non-receptive females still showed this preference, suggesting that they use information from chemical cues to assess the sexual attractiveness of potential female partners. Receptive females in contrast showed no such preferences. Our results demonstrate that females can decrease male harassment by associating with females that are more sexually attractive than themselves and that they perform active partner choices based on this relative attractiveness. We propose that this strategy is likely to represent an important pathway by which females can construct social niches that influence the decision-making of others to their advantage; in this case, to reduce the sexual harassment they experience.
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Marshall, Michael C.; Binderup, Andrew J.; Zandonà, Eugenia; Goutte, Sandra; Bassar, Ronald D.; El-Sabaawi, Rana W.; Thomas, Steven A.; Flecker, Alexander S.; Kilham, Susan S.; Reznick, David N.; Pringle, Cathy M.
2012-01-01
The effect of consumers on their resources has been demonstrated in many systems but is often confounded by trophic interactions with other consumers. Consumers may also have behavioral and life history adaptations to each other and to co-occurring predators that may additionally modulate their particular roles in ecosystems. We experimentally excluded large consumers from tile periphyton, leaves and natural benthic substrata using submerged electrified frames in three stream reaches with overlapping consumer assemblages in Trinidad, West Indies. Concurrently, we assessed visits to (non-electrified) control frames by the three most common large consumers–primarily insectivorous killifish (Rivulus hartii), omnivorous guppies (Poecilia reticulata) and omnivorous crabs (Eudaniela garmani). Consumers caused the greatest decrease in final chlorophyll a biomass and accrual rates the most in the downstream reach containing all three focal consumers in the presence of fish predators. Consumers also caused the greatest increase in leaf decay rates in the upstream reach containing only killifish and crabs. In the downstream reach where guppies co-occur with predators, we found significantly lower benthic invertebrate biomass in control relative to exclosure treatments than the midstream reach where guppies occur in the absence of predators. These data suggest that differences in guppy foraging, potentially driven by differences in their life history phenotype, may affect ecosystem structure and processes as much as their presence or absence and that interactions among consumers may further mediate their effects in these stream ecosystems. PMID:23028865
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Harper, David; Farag, Aida
2017-01-01
We evaluated the thermal regime and relative abundance of native and nonnative fish and invertebrates within Kelly Warm Spring and Savage Ditch, Grand Teton National Park, Wyoming. Water temperatures within the system remained relatively warm year-round with mean temperatures >20 °C near the spring source and >5 °C approximately 2 km downstream of the source. A total of 7 nonnative species were collected: Convict/Zebra Cichlid (Cichlasoma nigrofasciatum), Green Swordtail (Xiphophorus hellerii), Tadpole Madtom (Noturus gyrinus), Guppy (Poecilia reticulata), Goldfish (Carassius auratus), red-rimmed melania snail (Melanoides tuberculata), and American bullfrog tadpoles (Lithobates catesbeianus). Nonnative fish (Zebra Cichlids and Green Swordtails), red-rimmed melania snails, and bullfrog tadpoles dominated the upper 2 km of the system. Abundance estimates of the Zebra Cichlid exceeded 12,000 fish/km immediately downstream of the spring source. Relative abundance of native species increased movingdownstream as water temperatures attenuated with distance from the thermally warmed spring source; however, nonnative species were captured 4 km downstream from the spring. Fish diseases were prevalent in both native and nonnative fish from the Kelly Warm Spring pond. Clinostomum marginatum, a trematode parasite, was found in native species samples, and the tapeworm Diphyllobothrium dendriticum was present in samples from nonnative species. Diphyllobothrium dendriticum is rare in Wyoming. Salmonella spp. were also found in some samples of nonnative species. These bacteria are associated with aquarium fish and aquaculture and are generally not found in the wild.
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Hurtado-Gonzales, Jorge L.; Loew, Ellis R.; Uy, J. Albert C.
2014-01-01
The conspicuousness of animal signals is influenced by their contrast against the background. As such, signal conspicuousness will tend to vary in nature because habitats are composed of a mosaic of backgrounds. Variation in attractiveness could result in variation in conspecific mate choice and risk of predation, which, in turn, may create opportunities for balancing selection to maintain distinct polymorphisms. We quantified male coloration, the absorbance spectrum of visual pigments and the photic environment of Poecilia parae, a fish species with five distinct male color morphs: a drab (i.e., grey), a striped, and three colorful (i.e., blue, red and yellow) morphs. Then, using physiological models, we assessed how male color patterns can be perceived in their natural visual habitats by conspecific females and a common cichlid predator, Aequidens tetramerus. Our estimates of chromatic and luminance contrasts suggest that the three most colorful morphs were consistently the most conspicuous across all habitats. However, variation in the visual background resulted in variation in which morph was the most conspicuous to females at each locality. Likewise, the most colorful morphs were the most conspicuous morphs to cichlid predators. If females are able to discriminate between conspicuous prospective mates and those preferred males are also more vulnerable to predation, variable visual habitats could influence the direction and strength of natural and sexual selection, thereby allowing for the persistence of color polymorphisms in natural environments. PMID:24987856
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Kant, Rajni; Haq, S; Srivastava, H C; Sharma, V P
2013-03-01
Mosquito control with the use of insecticides is faced with the challenges of insecticide resistance in disease vectors, community refusal, their high cost, operational difficulties, and environmental concern. In view of this, integrated vector control strategies with the use of larvivorous fishes such as Guppy (Poecilia reticulata) and Gambusia (G. affinis) as biological control agents were used in controlling mosquito breeding in different types of breeding places such as intradomestic containers, various types of wells, rice-fields, pools, ponds and elsewhere in malaria prone rural areas of central Gujarat. Attempts were also made to demonstrate composite fish culture in unused abandoned village ponds by culturing Guppy along with the food fishes such as Rohu (Labeo rohita), Catla (Catla catla) and Mrigal (Cirrhinus mrigala). Income generated from these ponds through sale of fishes was utilized for mosquito control and village development. The technology was later adopted by the villagers themselves and food fish culture was practised in 23 ponds which generated an income of Rs 1,02,50,992 between 1985 and 2008. The number of villages increased from 13 to 23 in 2008 and there was also gradual increase of income from Rs 3,66,245 in 1985-90 to Rs 55,06,127 in 2002-08 block. It is concluded that larvivorous fishes can be useful tool in controlling mosquito breeding in certain situations and their use along with composite fish culture may also generate income to make the programme self-sustainable.
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Convergent evolution of reduced energy demands in extremophile fish
Arias-Rodriguez, Lenin; Tobler, Michael
2017-01-01
Convergent evolution in organismal function can arise from nonconvergent changes in traits that contribute to that function. Theory predicts that low resource availability and high maintenance costs in extreme environments select for reductions in organismal energy demands, which could be attained through modifications of body size or metabolic rate. We tested for convergence in energy demands and underlying traits by investigating livebearing fish (genus Poecilia) that have repeatedly colonized toxic, hydrogen sulphide-rich springs. We quantified variation in body size and routine metabolism across replicated sulphidic and non-sulphidic populations in nature, modelled total organismal energy demands, and conducted a common-garden experiment to test whether population differences had a genetic basis. Sulphidic populations generally exhibited smaller body sizes and lower routine metabolic rates compared to non-sulphidic populations, which together caused significant reductions in total organismal energy demands in extremophile populations. Although both mechanisms contributed to variation in organismal energy demands, variance partitioning indicated reductions of body size overall had a greater effect than reductions of routine metabolism. Finally, population differences in routine metabolism documented in natural populations were maintained in common-garden reared individuals, indicating evolved differences. In combination with other studies, these results suggest that reductions in energy demands may represent a common theme in adaptation to physiochemical stressors. Selection for reduced energy demand may particularly affect body size, which has implications for life history evolution in extreme environments. PMID:29077740
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Simon, Troy N.; Bassar, Ronald D.; Binderup, Andrew J.; Flecker, Alex S.; Freeman, Mary C.; Gilliam, James F.; Marshall, Michael C.; Thomas, Steve A.; Travis, Joseph; Reznick, David N.; Pringle, Catherine M.
2017-01-01
While previous studies have shown that evolutionary divergence alters ecological processes in small-scale experiments, a major challenge is to assess whether such evolutionary effects are important in natural ecosystems at larger spatial scales. At the landscape scale, across eight streams in the Caroni drainage, we found that the presence of locally adapted populations of guppies (Poecilia reticulata) is associated with reduced algal biomass and increased invertebrate biomass, while the opposite trends were true in streams with experimentally introduced populations of non-locally adapted guppies. Exclusion experiments conducted in two separate reaches of a single stream showed that guppies with locally adapted phenotypes significantly reduced algae with no effect on invertebrates, while non-adapted guppies had no effect on algae but significantly reduced invertebrates. These divergent effects of phenotype on stream ecosystems are comparable in strength to the effects of abiotic factors (e.g., light) known to be important drivers of ecosystem condition. They also corroborate the results of previous experiments conducted in artificial streams. Our results demonstrate that local adaptation can produce phenotypes with significantly different effects in natural ecosystems at a landscape scale, within a tropical watershed, despite high variability in abiotic factors: five of the seven physical and chemical parameters measured across the eight study streams varied by more than one order of magnitude. Our findings suggest that ecosystem structure is, in part, an evolutionary product and not simply an ecological pattern.
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Evans, Jonathan P.; Gasparini, Clelia; Holwell, Gregory I.; Ramnarine, Indar W.; Pitcher, Trevor E.; Pilastro, Andrea
2011-01-01
The role of sexual selection in fuelling genital evolution is becoming increasingly apparent from comparative studies revealing interspecific divergence in male genitalia and evolutionary associations between male and female genital traits. Despite this, we know little about intraspecific variance in male genital morphology, or how male and female reproductive traits covary among divergent populations. Here we address both topics using natural populations of the guppy, Poecilia reticulata, a livebearing fish that exhibits divergent patterns of male sexual behaviour among populations. Initially, we performed a series of mating trials on a single population to examine the relationship between the morphology of the male's copulatory organ (the gonopodium) and the success of forced matings. Using a combination of linear measurements and geometric morphometrics, we found that variation in the length and shape of the gonopodium predicted the success of forced matings in terms of the rate of genital contacts and insemination success, respectively. We then looked for geographical divergence in these traits, since the relative frequency of forced matings tends to be greater in high-predation populations. We found consistent patterns of variation in male genital size and shape in relation to the level of predation, and corresponding patterns of (co)variation in female genital morphology. Together, these data enable us to draw tentative conclusions about the underlying selective pressures causing correlated patterns of divergence in male and female genital traits, which point to a role for sexually antagonistic selection. PMID:21270040
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Shuhaimi-Othman, M.; Nadzifah, Y.; Nur-Amalina, R.; Umirah, N. S.
2012-01-01
Freshwater quality criteria for iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) were developed with particular reference to aquatic biota in Malaysia, and based on USEPA's guidelines. Acute toxicity tests were performed on eight different freshwater domestic species in Malaysia which were Macrobrachium lanchesteri (prawn), two fish: Poecilia reticulata and Rasbora sumatrana, Melanoides tuberculata (snail), Stenocypris major (ostracod), Chironomus javanus (midge larvae), Nais elinguis (annelid), and Duttaphrynus melanostictus (tadpole) to determine 96 h LC50 values for Fe, Pb, Ni, and Zn. The final acute value (FAV) for Fe, Pb, Ni, and Zn were 74.5, 17.0, 165, and 304.9 μg L−1, respectively. Using an estimated acute-to-chronic ratio (ACR) of 8.3, the value for final chronic value (FCV) was derived. Based on FAV and FCV, a criterion maximum concentration (CMC) and a criterion continuous concentration (CCC) for Fe, Pb, Ni, and Zn that are 37.2, 8.5, 82.5, and 152.4 μg L−1 and 9.0, 2.0, 19.9, and 36.7 μg L−1, respectively, were derived. The results of this study provide useful data for deriving national or local water quality criteria for Fe, Pb, Ni, and Zn based on aquatic biota in Malaysia. Based on LC50 values, this study indicated that N. elinguis, M. lanchesteri, N. elinguis, and R. sumatrana were the most sensitive to Fe, Pb, Ni, and Zn, respectively. PMID:22919358
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Do humans (Homo sapiens) and fish (Pterophyllum scalare) make similar numerosity judgments?
Miletto Petrazzini, Maria Elena; Agrillo, Christian; Izard, Véronique; Bisazza, Angelo
2016-11-01
Numerous studies have shown that many animal species can be trained to discriminate between stimuli differing in numerosity. However, in the absence of generalization tests with untrained numerosities, what decision criterion was used by subjects remains unclear: the subjects may succeed by selecting a specific number of items (a criterion over absolute numerosities), or by applying a more general relative numerosity rule, for example, selecting the larger/smaller quantity of items. The latter case may require more powerful representations, supporting judgments of order ("more/less") beyond simple "same/different" judgments, but a relative numerosity rule may also be more adaptive. In previous research, we showed that guppies (Poecilia reticulata) spontaneously prefer relative numerosity rules. To date it is unclear whether this preference is shared by other fish and, more broadly, other species. Here we compared the performance of angelfish (Pterophyllum scalare) with that of human adults (Homo sapiens) in a task in which subjects were initially trained to select arrays containing 10 dots (either in 5 vs. 10 or 10 vs. 20 comparisons). Subsequently they were tested with the previously trained numerosity and a novel numerosity (respectively, 20 or 5). In the absence of explicit instructions, both species spontaneously favored a relative rule, selecting the novel numerosity. These similarities demonstrate that, beyond shared representations for numerical quantities, vertebrate species may also share a system for taking decisions about quantities. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
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The prevalence of parasites in ornamental fish from fish market in Medan
NASA Astrophysics Data System (ADS)
Dewi, R. R.; Desrita; Fadhilla, A.
2018-02-01
Parasites still become the major problem in ornamental fish as the fast grown of its trading in Indonesia. Parasites causes diseases in ornamental fish hence followed by death and reducing its appearence. In this study, the prevalence of parasites in 100 apparently healthy ornamental fishes namely Guppy (Poecilia reticulate) and Goldfish (Carrasius auratus) were determined. The method of this research used was survey in local fish market in Medan from March to May 2017 The aim of this study was to determine the parasite that infects aquarium fishes and find out its prevalence. For this purpose, ornamental fishes were examined for parasites from their skin, fin, gill and intestine using wet mount method under a light microscope. The survey result showed that parasites that infect Guppy and Goldfish were Monogenea (Dactylogyrus sp and Gyrodactylus sp) in their skin and gill, Protozoa (piscinodinium sp) in their gill and Nematoda (Capillaria sp) in abdominal cavity. Prevalence rate of parasites that attack Guppy in Medan is Dactylogyrus sp (8%), Gyrodactylus sp (14 %), Piscinodinium sp (6%) and Capillaria sp (8%). Then, prevalence rate of Capilaria sp that attack Goldfish is 4%. The conclusion of this work revealed that the prevalence rate of ectoparasite and endoparasites in ornamental fishes in Medan had the low rate as well as there was no pathological findings is observed. However, these parasites could be a harmful parasitic diseases in case there is the changes in aquarium environment and improper fish handling.
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2005-10-01
The NTP chose to initiate studies in fish as an exploration of alternate or additional models for examining chemical toxicity and carcinogenicity. The use of small fish species in carcinogenicity testing offered potential advantages as a bioassay test system, including significant savings in cost and time over rodent studies. Large numbers of small fish could be easily maintained in a limited area. The two species chosen for study were guppy (Poecilia reticulata) and medaka (Oryzias latipes), both of which are hardy, easily maintained, and have a low occurrence of background lesions. The three chemicals chosen for study in fish had already been studied by the NTP in rodents, permitting a comparison of results between the two models. Two of the chemicals used (2,2-bis(bromomethyl)-1,3-propanediol and 1,2,3-trichloropropane) were mutagenic and multisite carcinogens in rats and mice. The third chemical, nitromethane, was nonmutagenic with a more modest carcinogenic response in rodents. Male and female guppies and medaka were exposed to 2,2-bis(bromomethyl)- 1,3-propanediol (greater than 99% pure), nitromethane, (greater than 99% pure), or 1,2,3-trichloropropane (99% pure) in aquaria water for up to 16 months. OVERALL STUDY DESIGN: Groups of approximately 220 guppies (two replicates of 110) were maintained in aquaria water containing nominal concentrations of 0, 24, 60, or 150 mg/L 2,2-bis(bromomethyl)-1,3-propanediol; 0, 10, 30, or 70 mg/L nitromethane; or 0, 4.5, 9.0, or 18.0 mg/L 1,2,3-trichloropropane. Groups of approximately 340 medaka (two replicates of 170) were maintained in aquaria water containing 0, 24, 60, or 150 mg/L 2,2-bis(bromomethyl)-1,3-propanediol; 0, 10, 20, or 40 mg/L nitromethane; or 0, 4.5, 9.0, or 18.0 mg/L 1,2,3-trichloropropane. The overall study durations were 16 months for all guppy studies, 14 months for 2,2-bis(bromomethyl)-1,3-propanediol-exposed medaka, and 13 months for nitromethane- and 1,2,3-trichloropropane-exposed medaka. Ten
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Ali, Joseph; Labrique, Alain B; Gionfriddo, Kara; Pariyo, George; Gibson, Dustin G; Pratt, Bridget; Deutsch-Feldman, Molly; Hyder, Adnan A
2017-05-05
Mobile phone coverage has grown, particularly within low- and middle-income countries (LMICs), presenting an opportunity to augment routine health surveillance programs. Several LMICs and global health partners are seeking opportunities to launch basic mobile phone-based surveys of noncommunicable diseases (NCDs). The increasing use of such technology in LMICs brings forth a cluster of ethical challenges; however, much of the existing literature regarding the ethics of mobile or digital health focuses on the use of technologies in high-income countries and does not consider directly the specific ethical issues associated with the conduct of mobile phone surveys (MPS) for NCD risk factor surveillance in LMICs. In this paper, we explore conceptually several of the central ethics issues in this domain, which mainly track the three phases of the MPS process: predata collection, during data collection, and postdata collection. These include identifying the nature of the activity; stakeholder engagement; appropriate design; anticipating and managing potential harms and benefits; consent; reaching intended respondents; data ownership, access and use; and ensuring LMIC sustainability. We call for future work to develop an ethics framework and guidance for the use of mobile phones for disease surveillance globally. ©Joseph Ali, Alain B Labrique, Kara Gionfriddo, George Pariyo, Dustin G Gibson, Bridget Pratt, Molly Deutsch-Feldman, Adnan A Hyder. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 05.05.2017.
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The Changing Drug Culture: Emerging Drugs of Abuse and Legal Highs.
Albertson, Timothy E; Chenoweth, James A; Colby, Daniel K; Sutter, Mark E
2016-02-01
In recent years, there has been a large increase in the number of synthetic drugs used recreationally. One class of drugs is synthetic cannabinoids, which are sprayed onto herbal preparations and marketed under names such as K2 and spice. Others include amphetaminelike compounds, such as cathinones (eg, bath salts) and methylenedioxymethamphetamine (MDMA) (eg, ecstasy, Molly). New hallucinogens, such as Bromo-Dragonfly, and hallucinogens that have been used for centuries, such as Salvia divinorum, also are gaining popularity. Because these substances are sold labeled as not for human consumption and because the chemicals in them frequently change, they often are unregulated, and many users consider them legal, although they are not. Their use often goes undetected because testing for them is not included in routine drug screening. Nonetheless, these substances can be associated with significant toxicities, often because their concentrations are unpredictable. Adverse effects of synthetic cannabinoids include psychosis and other effects. Amphetaminelike drugs have stimulant effects and can cause hyponatremia and seizures. The new hallucinogens can cause serious vasoconstriction with ischemia. Clinicians, especially those working with adolescents and young adults (ie, the main users of these drugs), should be aware of these new substances and counsel patients about their adverse effects. Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.
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Air pollution and human fertility rates.
Nieuwenhuijsen, Mark J; Basagaña, Xavier; Dadvand, Payam; Martinez, David; Cirach, Marta; Beelen, Rob; Jacquemin, Bénédicte
2014-09-01
Some reports have suggested effects of air pollution on semen quality and success rates of in vitro fertilization (IVF) in humans and lower fertility rates in mice. However, no studies have evaluated the impact of air pollution on human fertility rates. We assessed the association between traffic related air pollution and fertility rates in humans in Barcelona, Spain (2011-2012). We hypothesized that higher air pollution levels would be associated with lower fertility rates. We calculated the general fertility rate which is the number of live births per 1000 women between the ages of 15 and 44 years per census tract. We used land use regression (LUR) modeling to estimate the air pollution concentrations (particulate matter, NO2/NOx) per census tract. We used Besag-York-Mollié models to quantify the relationship between air pollution and fertility rates with adjustment for a number of potential confounders such as maternal age and area level socio-economic status. We found a statistically significant reduction of fertility rates with an increase in traffic related air pollution levels, particularly for the coarse fraction of particulate matter (IRR=0.87 95% CI 0.82, 0.94 per IQR). This is the first study in humans to show an association between reduced fertility rates and higher traffic related air pollution levels. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Bai, Hong; Kong, Wen-Wen; Shao, Chang-Lun; Li, Yun; Liu, Yun-Zhang; Liu, Min; Guan, Fei-Fei; Wang, Chang-Yun
2016-04-01
Marine organisms often protect themselves against their predators by chemical defensive strategy. The second metabolites isolated from marine organisms and their symbiotic microbes have been proven to play a vital role in marine chemical ecology, such as ichthyotoxicity, allelopathy, and antifouling. It is well known that the microscale models for marine chemoecology assessment are urgently needed for trace quantity of marine natural products. Zebrafish model has been widely used as a microscale model in the fields of environment ecological evaluation and drug safety evaluation, but seldom reported for marine chemoecology assessment. In this work, zebrafish embryo toxicity microscale model was established for ichthyotoxicity evaluation of marine natural products by using 24-well microplate based on zebrafish embryo. Ichthyotoxicity was evaluated by observation of multiple toxicological endpoints, including coagulation egg, death, abnormal heartbeat, no spontaneous movement, delayed hatch, and malformation of the different organs during zebrafish embryogenesis periods at 24, 48, and 72 h post-fertilization (hpf). 3,4-Dichloroaniline was used as the positive control for method validation. Subsequently, the established model was applied to test the ichthyotoxic activity of the compounds isolated from corals and their symbiotic microbes and to isolate the bioactive secondary metabolites from the gorgonian Subergorgia mollis under bioassay guidance. It was suggested that zebrafish embryo toxicity microscale model is suitable for bioassay-guided isolation and preliminary bioactivity screening of marine natural products.
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Pellegrini, María C; Alonso-Salces, Rosa M; Umpierrez, María L; Rossini, Carmen; Fuselli, Sandra R
2017-04-01
This study aimed to characterize the chemical composition of Aloysia polystachia, Acantholippia seriphioides, Schinus molle, Solidago chilensis, Lippia turbinata, Minthostachys mollis, Buddleja globosa, and Baccharis latifolia essential oils (EOs), and to evaluate their antibacterial activities and their capacity to provoke membrane disruption in Paenibacillus larvae, the bacteria that causes the American Foulbrood (AFB) disease on honey bee larvae. The relationship between the composition of the EOs and these activities on P. larvae was also analyzed. Monoterpenes were the most abundant compounds in all EOs. All EOs showed antimicrobial activity against P. larvae and disrupted the cell wall and cytoplasmic membrane of P. larvae provoking the leakage of cytoplasmic constituents (with the exception of B. latifolia EO). While, the EOs' antimicrobial activity was correlated most strongly to the content of pulegone, carvone, (Z)-β-ocimene, δ-cadinene, camphene, terpinen-4-ol, elemol, β-pinene, β-elemene, γ-cadinene, α-terpineol, and bornyl acetate; the volatiles that better explained the membrane disruption were carvone, limonene, cis-carvone oxide, pentadecane, trans-carvyl acetate, trans-carvone oxide, trans-limonene oxide, artemisia ketone, trans-carveol, thymol, and γ-terpinene (positively correlated) and biciclogermacrene, δ-2-carene, verbenol, α-pinene, and α-thujene (negatively correlated). The studied EOs are proposed as natural alternative means of control for the AFB disease. © 2017 Wiley-VHCA AG, Zurich, Switzerland.
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in Mapping of Gastric Cancer Incidence in Iran
Asmarian, Naeimehossadat; Jafari-Koshki, Tohid; Soleimani, Ali; Taghi Ayatollahi, Seyyed Mohammad
2016-10-01
Background: In many countries gastric cancer has the highest incidence among the gastrointestinal cancers and is the second most common cancer in Iran. The aim of this study was to identify and map high risk gastric cancer regions at the county-level in Iran. Methods: In this study we analyzed gastric cancer data for Iran in the years 2003-2010. Areato- area Poisson kriging and Besag, York and Mollie (BYM) spatial models were applied to smoothing the standardized incidence ratios of gastric cancer for the 373 counties surveyed in this study. The two methods were compared in term of accuracy and precision in identifying high risk regions. Result: The highest smoothed standardized incidence rate (SIR) according to area-to-area Poisson kriging was in Meshkinshahr county in Ardabil province in north-western Iran (2.4,SD=0.05), while the highest smoothed standardized incidence rate (SIR) according to the BYM model was in Ardabil, the capital of that province (2.9,SD=0.09). Conclusion: Both methods of mapping, ATA Poisson kriging and BYM, showed the gastric cancer incidence rate to be highest in north and north-west Iran. However, area-to-area Poisson kriging was more precise than the BYM model and required less smoothing. According to the results obtained, preventive measures and treatment programs should be focused on particular counties of Iran. Creative Commons Attribution License
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1980-01-01
spookin all ;ruof os portain11g to t& r in exod to on tao o me - ovors tho an dm two svhoh rlean ,-l=]l be ~~~ttlsendt a do ealt ootuni •tkty toes Weo 48f...1 I . f4~~ 4 . . . ’?9z - --- -, -. £ 4, *-.’.-. ~ .’*~ 94.44 9 , - / I LA~ BorrrA-i 7. - ’- N I.f A: .... ,CS HARMO [. tfl. wq N NT~V.- LANL W
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Parasite transmission in social interacting hosts: Monogenean epidemics in guppies
Johnson, M.B.; Lafferty, K.D.; van, Oosterhout C.; Cable, J.
2011-01-01
Background: Infection incidence increases with the average number of contacts between susceptible and infected individuals. Contact rates are normally assumed to increase linearly with host density. However, social species seek out each other at low density and saturate their contact rates at high densities. Although predicting epidemic behaviour requires knowing how contact rates scale with host density, few empirical studies have investigated the effect of host density. Also, most theory assumes each host has an equal probability of transmitting parasites, even though individual parasite load and infection duration can vary. To our knowledge, the relative importance of characteristics of the primary infected host vs. the susceptible population has never been tested experimentally. Methodology/Principal Findings: Here, we examine epidemics using a common ectoparasite, Gyrodactylus turnbulli infecting its guppy host (Poecilia reticulata). Hosts were maintained at different densities (3, 6, 12 and 24 fish in 40 L aquaria), and we monitored gyrodactylids both at a population and individual host level. Although parasite population size increased with host density, the probability of an epidemic did not. Epidemics were more likely when the primary infected fish had a high mean intensity and duration of infection. Epidemics only occurred if the primary infected host experienced more than 23 worm days. Female guppies contracted infections sooner than males, probably because females have a higher propensity for shoaling. Conclusions/Significance: These findings suggest that in social hosts like guppies, the frequency of social contact largely governs disease epidemics independent of host density. ?? 2011 Johnson et al.
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Stephenson, Jessica F; van Oosterhout, Cock; Mohammed, Ryan S; Cable, Joanne
2015-02-01
Predation pressure can alter the morphology, physiology, life history, and behavior of prey; each of these in turn can change how surviving prey interact with parasites. These trait-mediated indirect effects may change in direction or intensity during growth or, in sexually dimorphic species, between the sexes. The Trinidadian guppy, Poecilia reticulata presents a unique opportunity to examine these interactions; its behavioral ecology has been intensively studied in wild populations with well-characterized predator faunas. Predation pressure is known to have driven the evolution of many guppy traits; for example, in high-predation sites, females (but not males) tend to shoal, and this anti-predator behavior facilitates parasite transmission. To test for evidence of predator-driven differences in infection in natural populations, we collected 4715 guppies from 62 sites across Trinidad between 2003 and 2009 and screened them for ectosymbionts, including Gyrodactylus. A novel model-averaging analysis revealed that females were more likely to be infected with Gyrodactylus parasites than males, but only in populations with both high predation pressure and high infection prevalence. We propose that the difference in shoaling tendency between the sexes could explain the observed difference in infection prevalence between males and females in high-predation sites. The infection rate of juveniles did not vary with predation regime, probably because juveniles face constant predation pressure from conspecific adults and therefore tend to shoal in both high- and low-predation sites. This represents the first evidence for age- and sex-specific trait-mediated indirect effects of predators on the probability of infection in their prey.
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Willing, Eva-Maria; Bentzen, Paul; van Oosterhout, Cock; Hoffmann, Margarete; Cable, Joanne; Breden, Felix; Weigel, Detlef; Dreyer, Christine
2010-03-01
Adaptation of guppies (Poecilia reticulata) to contrasting upland and lowland habitats has been extensively studied with respect to behaviour, morphology and life history traits. Yet population history has not been studied at the whole-genome level. Although single nucleotide polymorphisms (SNPs) are the most abundant form of variation in many genomes and consequently very informative for a genome-wide picture of standing natural variation in populations, genome-wide SNP data are rarely available for wild vertebrates. Here we use genetically mapped SNP markers to comprehensively survey genetic variation within and among naturally occurring guppy populations from a wide geographic range in Trinidad and Venezuela. Results from three different clustering methods, Neighbor-net, principal component analysis (PCA) and Bayesian analysis show that the population substructure agrees with geographic separation and largely with previously hypothesized patterns of historical colonization. Within major drainages (Caroni, Oropouche and Northern), populations are genetically similar, but those in different geographic regions are highly divergent from one another, with some indications of ancient shared polymorphisms. Clear genomic signatures of a previous introduction experiment were seen, and we detected additional potential admixture events. Headwater populations were significantly less heterozygous than downstream populations. Pairwise F(ST) values revealed marked differences in allele frequencies among populations from different regions, and also among populations within the same region. F(ST) outlier methods indicated some regions of the genome as being under directional selection. Overall, this study demonstrates the power of a genome-wide SNP data set to inform for studies on natural variation, adaptation and evolution of wild populations.
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Effects of ambient oxygen and size-selective mortality on growth and maturation in guppies
Diaz Pauli, Beatriz; Kolding, Jeppe; Jeyakanth, Geetha
2017-01-01
Abstract Growth, onset of maturity and investment in reproduction are key traits for understanding variation in life-history strategies. Many environmental factors affect variation in these traits, but for fish, hypoxia and size-dependent mortality have become increasingly important because of human activities, such as increased nutrient enrichment (eutrophication), climate warming and selective fishing. Here, we study experimentally the effect of oxygen availability on maturation and growth in guppies (Poecilia reticulata) from two different selected lines, one subjected to positive and the other negative size-dependent fishing. This is the first study to assess the effects of both reduced ambient oxygen and size-dependent mortality in fish. We show that reduced ambient oxygen led to stunting, early maturation and high reproductive investment. Likewise, lineages that had been exposed to high mortality of larger-sized individuals displayed earlier maturation at smaller size, greater investment in reproduction and faster growth. These life-history changes were particularly evident for males. The widely reported trends towards earlier maturation in wild fish populations are often interpreted as resulting from size-selective fishing. Our results highlight that reduced ambient oxygen, which has received little experimental investigation to date, can lead to similar phenotypic changes. Thus, changes in ambient oxygen levels can be a confounding factor that occurs in parallel with fishing, complicating the causal interpretation of changes in life-history traits. We believe that better disentangling of the effects of these two extrinsic factors, which increasingly affect many freshwater and marine ecosystems, is important for making more informed management decisions. PMID:28361001
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Sullam, Karen E; Rubin, Benjamin E R; Dalton, Christopher M; Kilham, Susan S; Flecker, Alexander S; Russell, Jacob A
2015-07-01
Diverse microbial consortia profoundly influence animal biology, necessitating an understanding of microbiome variation in studies of animal adaptation. Yet, little is known about such variability among fish, in spite of their importance in aquatic ecosystems. The Trinidadian guppy, Poecilia reticulata, is an intriguing candidate to test microbiome-related hypotheses on the drivers and consequences of animal adaptation, given the recent parallel origins of a similar ecotype across streams. To assess the relationships between the microbiome and host adaptation, we used 16S rRNA amplicon sequencing to characterize gut bacteria of two guppy ecotypes with known divergence in diet, life history, physiology and morphology collected from low-predation (LP) and high-predation (HP) habitats in four Trinidadian streams. Guts were populated by several recurring, core bacteria that are related to other fish associates and rarely detected in the environment. Although gut communities of lab-reared guppies differed from those in the wild, microbiome divergence between ecotypes from the same stream was evident under identical rearing conditions, suggesting host genetic divergence can affect associations with gut bacteria. In the field, gut communities varied over time, across streams and between ecotypes in a stream-specific manner. This latter finding, along with PICRUSt predictions of metagenome function, argues against strong parallelism of the gut microbiome in association with LP ecotype evolution. Thus, bacteria cannot be invoked in facilitating the heightened reliance of LP guppies on lower-quality diets. We argue that the macroevolutionary microbiome convergence seen across animals with similar diets may be a signature of secondary microbial shifts arising some time after host-driven adaptation.
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Individual consistency in exploratory behaviour and mating tactics in male guppies
NASA Astrophysics Data System (ADS)
Kelley, Jennifer L.; Phillips, Samuel C.; Evans, Jonathan P.
2013-10-01
While behavioural plasticity is considered an adaptation to fluctuating social and environmental conditions, many animals also display a high level of individual consistency in their behaviour over time or across contexts (generally termed ‘personality’). However, studies of animal personalities that include sexual behaviour, or functionally distinct but correlated traits, are relatively scarce. In this study, we tested for individual behavioural consistency in courtship and exploratory behaviour in male guppies ( Poecilia reticulata) in two light environments (high vs. low light intensity). Based on previous work on guppies, we predicted that males would modify their behaviour from sneak mating tactics to courtship displays under low light conditions, but also that the rank orders of courtship effort would remain unchanged (i.e. highly sexually active individuals would display relatively high levels of courtship under both light regimes). We also tested for correlations between courtship and exploratory behaviour, predicting that males that had high display rates would also be more likely to approach a novel object. Although males showed significant consistency in their exploratory and mating behaviour over time (1 week), we found no evidence that these traits constituted a behavioural syndrome. Furthermore, in contrast to previous work, we found no overall effect of the light environment on any of the behaviours measured, although males responded to the treatment on an individual-level basis, as reflected by a significant individual-by-environment interaction. The future challenge is to investigate how individual consistency across different environmental contexts relates to male reproductive success.
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Pinto, Hudson A; Griffin, Matt J; Quiniou, Sylvie M; Ware, Cynthia; Melo, Alan L
2016-01-01
Species of trematodes belonging to the genus Drepanocephalus are intestinal parasites of piscivorous birds, primarily cormorants (Phalachrocorax spp.), and are widely reported in the Americas. During a 4-year malacological study conducted on an urban lake in Brazil, 27-collar-spined echinostome cercariae were found in 1665/15,459 (10.7 %) specimens of Biomphalaria straminea collected. The cercariae were identified as Drepanocephalus spp. by sequencing the 18S (SSU) rDNA, ITS1/5.8S rDNA/ITS2 (ITS), 28S (LSU) rDNA region, cytochrome oxidase subunit 1 (CO1), and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) markers. In experimental life cycle studies, metacercariae developed in laboratory-reared guppies (Poecilia reticulata); however, attempts to infect birds and rodents were unsuccessful. Two closely related morphotypes of cercariae were characterized. One species, identified by molecular markers as a genetic variant of Drepanocephalus auritus (99.9 % similarity at SSU, ITS, LSU; 97.2 % at CO1; 95.8 % at ND1), differs slightly from an archived North American isolate of this species also sequenced as part of this study. A second species, putatively identified as Drepanocephalus sp., has smaller cercariae and demonstrates significant differences from D. auritus at the CO1 (11.0 %) and ND1 (13.6 %) markers. Aspects related to the morphological taxonomic identification of 27-collar-spined echinostome metacercariae are briefly discussed. This is the first report of the involvement of molluscs of the genus Biomphalaria in the transmission of Drepanocephalus and the first report of D. auritus in South America.
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Ao, Jingqun; Ding, Yang; Chen, Yuanyuan; Mu, Yinnan; Chen, Xinhua
2015-12-10
The C-type lectin-like receptors (CTLRs) play important roles in innate immunity as one type of pattern recognition receptors. Here, we cloned and characterized a C-type lectin-like receptor (LycCTLR) from large yellow croaker Larimichthys crocea. The full-length cDNA of LycCTLR is 880 nucleotides long, encoding a protein of 215 amino acids. The deduced LycCTLR contains a C-terminal C-type lectin-like domain (CTLD), an N-terminal cytoplasmic tail, and a transmembrane region. The CTLD of LycCTLR possesses six highly conserved cysteine residues (C1-C6), a conserved WI/MGL motif, and two sugar binding motifs, EPD (Glu-Pro-Asp) and WYD (Trp-Tyr-Asp). Ca(2+) binding site 1 and 2 were also found in the CTLD. The LycCTLR gene consists of five exons and four introns, showing the same genomic organization as tilapia (Oreochromis niloticus) and guppy (Poecilia retitculata) CTLRs. LycCTLR was constitutively expressed in various tissues tested, and its transcripts significantly increased in the head kidney and spleen after stimulation with inactivated trivalent bacterial vaccine. Recombinant LycCTLR (rLycCTLR) protein produced in Escherichia coli BL21 exhibited not only the hemagglutinating activity and a preference for galactose, but also the agglutinating activity against two food-borne pathogenic bacteria E. coli and Bacillus cereus in a Ca(2+)-dependent manner. These results indicate that LycCTLR is a potential galactose-binding C-type lectin that may play a role in the antibacterial immunity in fish.
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Lopes, K C; Ferrão-Filho, A S; Santos, E G N; Santos, C P
2018-03-01
Cylindrospermopsis raciborskii (Woloszynska) is a photosynthetic cyanobacterium that can produce cytotoxic (cylindrospermopsin) and neurotoxic cyanotoxins (saxitoxins). In Brazil the strains of C. raciborskii are reported to produce only saxitoxins (STX) and their effect on fish parasites has not been tested to date. The fish Poecilia vivipara Bloch and Schneider is a common host for the trematode Pygidiopsis macrostomum Travassos off the coast of Rio de Janeiro, and this fish-parasite interaction is a model for behavioural and ecotoxicological studies. The aim of this work was to evaluate the motility of metacercariae of P. macrostomum from P. vivipara exposed to 40 mg l-1 and 400 mg l-1 of crude lyophilized extract of the cyanobacterium C. raciborskii (CYRF-01) for 48 h. The fish were separated into groups of ten individuals and, after exposure, five fish from each group were dissected for counting and checking the motility of metacercariae. The other five fish were dissected after 48 h in clean water. The detection and quantification of STX in the solutions of cyanobacteria, and the gills and guts of fish, were performed by an enzyme-linked immunosorbent assay. The crude extract of C. raciborskii caused temporary paralysis in metacercariae of P. macrostomum after exposure of fish to both concentrations, and the motility recovered after the fish were kept for 48 h in clean water. STX was detected in the guts and gills of all fish analysed, suggesting that this toxin is involved in the paralysis of metacercariae. This is the first report on the action of neurotoxins in metacercariae of fish.
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An experimental test of alternative population augmentation scenarios.
Kronenberger, John A; Gerberich, Jill C; Fitzpatrick, Sarah W; Broder, E Dale; Angeloni, Lisa M; Funk, W Chris
2018-01-19
Human land use is fragmenting habitats worldwide and inhibiting dispersal among previously connected populations of organisms, often leading to inbreeding depression and reduced evolutionary potential in the face of rapid environmental change. To combat this augmentation of isolated populations with immigrants is sometimes used to facilitate demographic and genetic rescue. Augmentation with immigrants that are genetically and adaptively similar to the target population effectively increases population fitness, but if immigrants are very genetically or adaptively divergent, augmentation can lead to outbreeding depression. Despite well-cited guidelines for the best practice selection of immigrant sources, often only highly divergent populations remain, and experimental tests of these riskier augmentation scenarios are essentially nonexistent. We conducted a mesocosm experiment with Trinidadian guppies (Poecilia reticulata) to test the multigenerational demographic and genetic effects of augmenting 2 target populations with 3 types of divergent immigrants. We found no evidence of demographic rescue, but we did observe genetic rescue in one population. Divergent immigrant treatments tended to maintain greater genetic diversity, abundance, and hybrid fitness than controls that received immigrants from the source used to seed the mesocosms. In the second population, divergent immigrants had a slightly negative effect in one treatment, and the benefits of augmentation were less apparent overall, likely because this population started with higher genetic diversity and a lower reproductive rate that limited genetic admixture. Our results add to a growing consensus that gene flow can increase population fitness even when immigrants are more highly divergent and may help reduce uncertainty about the use of augmentation in conservation. © 2018 Society for Conservation Biology.
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Jacquin, L; Dybwad, C; Rolshausen, G; Hendry, A P; Reader, S M
2017-01-01
Human-induced perturbations such as crude-oil pollution can pose serious threats to aquatic ecosystems. To understand these threats fully it is important to establish both the immediate and evolutionary effects of pollutants on behaviour and cognition. Addressing such questions requires comparative and experimental study of populations that have evolved under different levels of pollution. Here, we compared the exploratory, activity and social behaviour of four populations of Trinidadian guppies (Poecilia reticulata) raised in common garden conditions for up to three generations. Two of these populations originated from tributaries with a long history of human-induced chronic crude-oil pollution with polycyclic aromatic hydrocarbons due to oil exploitation in Trinidad, the two others originating from non-polluted control sites. Laboratory-raised guppies from the oil-polluted sites were less exploratory in an experimental maze than guppies from the non-polluted sites and in a similar manner for the two independent rivers. We then compared the plastic behavioural responses of the different populations after an acute short-term experimental exposure to crude oil and found a decrease in exploration (but not in activity or shoaling) in the oil-exposed fish compared to the control subjects over all four populations. Taken together, these results suggest that both an evolutionary history with oil and an acute exposure to oil depressed guppy exploratory behaviour. We discuss whether the behavioural divergence observed represents adaptation to human-induced pollutants, the implications for conservation and the possible knock-on effects for information discovery and population persistence in fish groups.
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Gasparini, Clelia; Congiu, Leonardo; Pilastro, Andrea
2015-08-01
Females that mate multiply have the possibility to exert postcopulatory choice and select more compatible sperm to fertilize eggs. Prior work suggests that dissimilarity in major histocompatibility complex (MHC) plays an important role in determining genetic compatibility between partners. Favouring a partner with dissimilar MHC alleles would result in offspring with high MHC diversity and therefore with enhanced survival thanks to increased resistance to pathogens and parasites. The high variability of MHC genes may further allow discrimination against the sperm from related males, reducing offspring homozygosity and inbreeding risk. Despite the large body of work conducted at precopulatory level, the role of MHC similarity between partners at postcopulatory level has been rarely investigated. We used an internal fertilizing fish with high level of multiple matings (Poecilia reticulata) to study whether MHC similarity plays a role in determining the outcome of fertilization when sperm from two males compete for the same set of eggs. We also controlled for genomewide similarity by determining similarity at 10 microsatellite loci. Contrary to prediction, we found that the more MHC-similar male sired more offspring while similarity at the microsatellite loci did not predict the outcome of sperm competition. Our results suggest that MHC discrimination may be involved in avoidance of hybridization or outbreeding rather than inbreeding avoidance. This, coupled with similar findings in salmon, suggests that the preference for MHC-dissimilar mates is far from being unanimous and that pre- and postcopulatory episodes of sexual selection can indeed act in opposite directions. © 2015 John Wiley & Sons Ltd.
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Gachet, María Salomé; Lecaro, Javier Salazar; Kaiser, Marcel; Brun, Reto; Navarrete, Hugo; Muñoz, Ricardo A; Bauer, Rudolf; Schühly, Wolfgang
2010-03-02
For the assessment of the in vitro anti-protozoal potential of plants traditionally used in Ecuador in the treatment of leishmaniasis, a combined approach based on interviews with healers as well as a literature search was carried out. From three regions of Ecuador, 256 local healers called "Agents of Traditional Medicine" (ATMs) were interviewed about their knowledge of the use of plants to treat and heal the illness recognized by the ATMs as leishmaniasis. From literature sources, 14 plants were identified as being used in the treatment of leishmaniasis. Subsequently, plant material was collected from a representative selection of 39 species. A total of 140 extracts were screened in vitro against Leishmania donovani, Plasmodium falciparum, Trypanosoma brucei rhodesiense and Trypanosoma cruzi. Additionally, these extracts were evaluated for their anti-microbial activities using five gram-positive and -negative bacteria as well as Candida albicans. The survey resulted in 431 use-records for 145 plant-taxa used for the treatment of leishmaniasis. The 10 most frequently reported taxa accounted for 37.7% of all records. In the case of leishmaniasis, activity was observed for Elephantopus mollis, Minquartia guianensis, Bocconia integrifolia, Gouania lupuloides, Scoparia dulcis, an as-yet-unidentified species of Piper and Brugmansia. For the leaves of M. guianensis and the twigs and bark of G. lupuloides a good selectivity index (SI) was found. IC(50) values and the SI of active plant extracts are presented. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.
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Comparison of some secondary metabolite content in the seventeen species of the Boraginaceae family.
Dresler, Sławomir; Szymczak, Grażyna; Wójcik, Małgorzata
2017-12-01
The Boraginaceae family comprises plants that have important therapeutic and cosmetic applications. Their pharmacological effect is related to the presence of naphthaquinones, flavonoids, terpenoids, phenols, or purine derivative - allantoin. In the present study, comparison of some secondary metabolite content and phytochemical relationship between 17 species of the Boraginaceae family were analyzed. High performance capillary electrophoresis (HPCE) was used to perform a chemometric analysis in the following Boraginaceae species: Anchusa azurea Mill., Anchusa undulata L., Borago officinalis L., Buglossoides purpurocaerulea (L.) I.M. Johnst., Cerinthe minor L., Cynoglossum creticum Mill, Echium italicum L., Echium russicum J.F. Gmel., Echium vulgare L., Lindelofia macrostyla (Bunge) Popov (syn. Lindelofia anchusoides (Lindl.) Lehm.), Lithospermum officinale L., Nonea lutea (Desr.) DC., Omphalodes verna Moench (syn. Cynoglossum omphaloides L.), Pulmonaria mollis Wulfen ex Hornem., Pulmonaria obscura Dumort., Symphytum cordatum Waldst. & Kit ex Willd., and Symphytum officinale L. Six active compounds in shoot extracts (allantoin, p-hydroxybenzoic acid, rutin, hydrocaffeic acid, rosmarinic acid, and chlorogenic acid) and four compounds in root extracts (allantoin, hydrocaffeic acid, rosmarinic acid, and shikonin) were identified. The presence and abundance of these compounds were used for the characterization of the species and for revealing their phytochemical similarity and differentiation. The present study provides the first comprehensive report of the extraction and quantification of several compounds in Boraginaceae species (some of them for the first time). Among the 17 species studied, species with potentially high pharmacological activity were recognized.
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Bohn, Jens Michael; Heß, Martin
2014-07-29
An examination of seven Antarctic brooding cucumariid and psolid holothurian species revealed a variety of characters all of them have in common: (1) All are gonochoric. (2) A genital papilla is present on the oral disc (permanent and digitiform in males). (3) Females brood their offspring in five anterior interradial brood pouches that are situated at the transition of body to introvert. (4) Multiple spermatozoa are always bundled to bunch-like spermato-zeugmata. (5) The spermatozoa have a fusiform head and a hollow cylinder-like mid-piece encircling the anterior end of the flagellum. This combination of characters so far is unique, and indicates a close relationship based on common origin. As a consequence, we unite all species sharing this set of synapomorphies in the genus Echinopsolus Gutt, 1990. The herewith included species are: E. acanthocola Gutt, 1990, E. acutus (Massin, 1992) comb. nov., E. charcoti (Vaney, 1906) comb. nov., E. koehleri (Vaney, 1914) comb. nov., E. mollis (Ludwig & Heding, 1935) comb. nov., E. parvipes Massin, 1992 and E. splendidus (Gutt, 1990) comb. nov.. Because the current assignment of Echinopsolus to the family Psolidae can not be retained, the genus is tranferred to the family Cucumariidae, as relationships to taxa within this family are obvious. The peculiar spermatozoa and spermato-zeugmata of all Echinopsolus species are described using light- and electron-microscopical techniques and the results are evaluated and discussed concerning their taxonomy and phylogeny.
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Jacquin, L; Reader, S M; Boniface, A; Mateluna, J; Patalas, I; Pérez-Jvostov, F; Hendry, A P
2016-07-01
Natural enemies such as predators and parasites are known to shape intraspecific variability of behaviour and personality in natural populations, yet several key questions remain: (i) What is the relative importance of predation vs. parasitism in shaping intraspecific variation of behaviour across generations? (ii) What are the contributions of genetic and plastic effects to this behavioural divergence? (iii) And to what extent are responses to predation and parasitism repeatable across independent evolutionary lineages? We addressed these questions using Trinidadian guppies (Poecilia reticulata) (i) varying in their exposure to dangerous fish predators and Gyrodactylus ectoparasites for (ii) both wild-caught F0 and laboratory-reared F2 individuals and coming from (iii) multiple independent evolutionary lineages (i.e. independent drainages). Several key findings emerged. First, a population's history of predation and parasitism influenced behavioural profiles, but to different extent depending on the behaviour considered (activity, shoaling or boldness). Second, we had evidence for some genetic effects of predation regime on behaviour, with differences in activity of F2 laboratory-reared individuals, but not for parasitism, which had only plastic effects on the boldness of wild-caught F0 individuals. Third, the two lineages showed a mixture of parallel and nonparallel responses to predation/parasitism, with parallel responses being stronger for predation than for parasitism and for activity and boldness than for shoaling. These findings suggest that different sets of behaviours provide different pay-offs in alternative predation/parasitism environments and that parasitism has more transient effects in shaping intraspecific variation of behaviour than does predation. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.
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Intrasexual competition enhances reproductive isolation between locally adapted populations
Arias-Rodriguez, Lenin; Plath, Martin
2018-01-01
Abstract During adaptation to different habitat types, both morphological and behavioral traits can undergo divergent selection. Males often fight for status in dominance hierarchies and rank positions predict reproductive success. Ecotypes with reduced fighting abilities should have low reproductive success when migrating into habitats that harbor ecotypes with superior fighting abilities. Livebearing fishes in the Poecilia mexicana-species complex inhabit not only regular freshwater environments, but also independently colonized sulfidic (H2S-containing) habitats in three river drainages. In the current study, we found fighting intensities in staged contests to be considerably lower in some but not all sulfidic surface ecotypes and the sulfidic cave ecotype compared with populations from non-sulfidic surface sites. This is perhaps due to selection imposed by H2S, which hampers oxygen uptake and transport, as well as cellular respiration. Furthermore, migrants from sulfidic habitats may lose fights even if they do not show overall reduced aggressiveness, as physiological performance is likely to be challenged in the non-sulfidic environment to which they are not adapted. To test this hypothesis, we simulated migration of H2S-adapted males into H2S-free waters, as well as H2S-adapted cave-dwelling males into sulfidic surface waters. We found that intruders established dominance less often than resident males, independent of whether or not they showed reduced aggressiveness overall. Our study shows that divergent evolution of male aggressive behavior may also contribute to the maintenance of genetic differentiation in this system and we call for more careful evaluation of male fighting abilities in studies on ecological speciation. PMID:29492045
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Weadick, Cameron J; Loew, Ellis R; Rodd, F Helen; Chang, Belinda S W
2012-10-01
The Trinidadian pike cichlid (Crenicichla frenata) is a major predator of the guppy (Poecilia reticulata), a model system for visual ecology research, and visual predation by the pike cichlid is known to select for male guppies with reduced short-wavelength reflectance. However, an early study of the pike cichlid's visual system suggested a lack of short-wavelength-sensitive cone photoreceptors, a surprising finding as many African cichlids have highly developed short-wavelength vision. In this study, we found evidence for only four expressed cone opsins (LWS, RH2a, SWS2a, and SWS2b), plus one pseudogene (RH2b). Taken together with our microspectrophotometry data, which revealed the presence of three types of cone photoreceptor, including one sensitive to short-wavelength light, this would indicate a broader spectral capacity than previously believed from earlier visual studies of this fish. Relative to the highly diverse African cichlids, however, this Neotropical cichlid appears to have a greatly reduced opsin complement, reflecting both gene loss along the Neotropical lineage (lacking functional RH2b and, possibly, SWS1 opsins) and gene duplication within the African clade (which possesses paralogous RH2aα and RH2aβ opsins). Molecular evolutionary analyses show that positive selection has shaped the SWS2b and RH1 opsins along the Neotropical lineage, which may be indicative of adaptive evolution to alter nonspectral aspects of opsin biology. These results represent the first molecular evolutionary study of visual pigments in a Neotropical cichlid and thus provide a foundation for further study of a morphologically and ecologically diverse clade that has been understudied with respect to the link between visual ecology and diversification.
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Gosselin, Jennifer L; Anderson, James J
2013-12-01
Determining when resource competition increases survivorship can reveal processes underlying population dynamics and reinforce the importance of heterogeneity among individuals in conservation. We ran an experiment mimicking the effects of competition in a growing season on survivorship during a selection event (e.g., overwinter starvation, drought). Using a model fish species (Poecilia reticulata), we studied how food availability and competition affect mass in a treatment stage, and subsequently survivorship in a challenge stage of increased temperature and starvation. The post-treatment mean mass was strongly related to the mean time to mortality and mass at mortality at all levels of competition. However, competition increased variance in mass and extended the right tail of the survivorship curve, resulting in a greater number of individuals alive beyond a critical temporal threshold ([Formula: see text]) than without competition. To realize the benefits from previously experienced competition, the duration of the challenge ([Formula: see text]) following the competition must exceed the critical threshold [Formula: see text] (i.e., competition increases survivorship when [Formula: see text]). Furthermore, this benefit was equivalent to increasing food availability by 20 % in a group without competition in our experiment. The relationship of [Formula: see text] to treatment and challenge conditions was modeled by characterizing mortality through mass loss in terms of the stochastic rate of loss of vitality (individual's survival capacity). In essence, when the duration of a selection event exceeds [Formula: see text], competition-induced heterogeneity buffers against mortality through overcompensation processes among individuals of a cohort. Overall, our study demonstrates an approach to quantify how early life stage heterogeneity affects survivorship.
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Sullam, Karen E; Rubin, Benjamin ER; Dalton, Christopher M; Kilham, Susan S; Flecker, Alexander S; Russell, Jacob A
2015-01-01
Diverse microbial consortia profoundly influence animal biology, necessitating an understanding of microbiome variation in studies of animal adaptation. Yet, little is known about such variability among fish, in spite of their importance in aquatic ecosystems. The Trinidadian guppy, Poecilia reticulata, is an intriguing candidate to test microbiome-related hypotheses on the drivers and consequences of animal adaptation, given the recent parallel origins of a similar ecotype across streams. To assess the relationships between the microbiome and host adaptation, we used 16S rRNA amplicon sequencing to characterize gut bacteria of two guppy ecotypes with known divergence in diet, life history, physiology and morphology collected from low-predation (LP) and high-predation (HP) habitats in four Trinidadian streams. Guts were populated by several recurring, core bacteria that are related to other fish associates and rarely detected in the environment. Although gut communities of lab-reared guppies differed from those in the wild, microbiome divergence between ecotypes from the same stream was evident under identical rearing conditions, suggesting host genetic divergence can affect associations with gut bacteria. In the field, gut communities varied over time, across streams and between ecotypes in a stream-specific manner. This latter finding, along with PICRUSt predictions of metagenome function, argues against strong parallelism of the gut microbiome in association with LP ecotype evolution. Thus, bacteria cannot be invoked in facilitating the heightened reliance of LP guppies on lower-quality diets. We argue that the macroevolutionary microbiome convergence seen across animals with similar diets may be a signature of secondary microbial shifts arising some time after host-driven adaptation. PMID:25575311
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Muñoz, Nicolas J; Breckels, Ross D; Neff, Bryan D
2012-10-01
Global warming poses a threat to many ectothermic organisms because of the harmful effects that elevated temperatures can have on resting metabolic rate (RMR) and body size. This study evaluated the thermal sensitivity of Trinidadian guppies (Poecilia reticulata) by describing the effects of developmental temperature on mass, burst speed and RMR, and investigated whether these tropical fish can developmentally acclimate to their thermal conditions. These traits were measured following exposure to one of three treatments: 70 days at 23, 25, 28 or 30°C (acclimated groups); 6 h at 23, 28 or 30°C following 70 days at 25°C (unacclimated groups); or 6 h at 25°C following 70 days in another 25°C tank (control group). Body mass was lower in warmer temperatures, particularly amongst females and individuals reared at 30°C. The burst speed of fish acclimated to each temperature did not differ and was marginally higher than that of unacclimated fish, indicative of complete compensation. Conversely, acclimated and unacclimated fish did not differ in their RMR at each temperature. Amongst the acclimated groups, RMR was significantly higher at 30°C, indicating that guppies may become thermally limited at this temperature as a result of less energy being available for growth, reproduction and locomotion. Like other tropical ectotherms, guppies appear to be unable to adjust their RMR through physiological acclimation and may consequently be susceptible to rising temperatures. Also, because larger females have higher fecundity, our data suggest that fecundity will be reduced in a warmer climate, potentially decreasing the viability of guppy populations.
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Krebs, Justin M.; McIvor, Carole C.; Bell, Susan S.
2014-01-01
To assess the potential influence of coastal development on estuarine-habitat quality, we characterized land use and the intensity of land development surrounding small tidal tributaries in Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban, or man-made (i.e., mosquito-control ditches). Over one third (37 %) of the tributaries have been heavily developed based on landscape development intensity (LDI) index values >5.0, while fewer than one third (28 %) remain relatively undeveloped (LDI < 3.0). We then examined the nekton community from 11 tributaries in watersheds representing the four defined land-use classes. Whereas mean nekton density was independent of land use, species richness and nekton-community structure were significantly different between urban and non-urban (i.e., undeveloped, industrial, man-made) tributaries. In urban creeks, the community was species-poor and dominated by high densities of poeciliid fishes, Poecilia latipinna and Gambusia holbrooki, while typically dominant estuarine taxa including Menidia spp., Fundulus grandis, and Adinia xenica were in low abundance and palaemonid grass shrimp were nearly absent. Densities of economically important taxa in urban creeks were only half that observed in five of the six undeveloped or industrial creeks, but were similar to those observed in mosquito ditches suggesting that habitat quality in urban and mosquito-ditch tributaries is suboptimal compared to undeveloped tidal creeks. Furthermore, five of nine common taxa were rarely collected in urban creeks. Our results suggest that urban development in coastal areas has the potential to alter the quality of habitat for nekton in small tidal tributaries as reflected by variation in the nekton community.
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Ovarian fluid mediates the temporal decline in sperm viability in a fish with sperm storage.
Gasparini, Clelia; Evans, Jonathan P
2013-01-01
A loss of sperm viability and functionality during sperm transfer and storage within the female reproductive tract can have important fitness implications by disrupting fertilization and impairing offspring development and survival. Consequently, mechanisms that mitigate the temporal decline in sperm function are likely to be important targets of selection. In many species, ovarian fluid is known to regulate and maintain sperm quality. In this paper, we use the guppy Poecilia reticulata, a highly polyandrous freshwater fish exhibiting internal fertilization and sperm storage, to determine whether ovarian fluid (OF) influences the decline in sperm viability (the proportion of live sperm in the ejaculate) over time and whether any observed effects depend on male sexual ornamentation. To address these questions we used a paired experimental design in which ejaculates from individual males were tested in vitro both in presence and absence of OF. Our results revealed that the temporal decline in sperm viability was significantly reduced in the presence of OF compared to a saline control. This finding raises the intriguing possibility that OF may play a role in mediating the decline in sperm quality due to the deleterious effects of sperm ageing, although other possible explanations for this observation are discussed. Interestingly, we also show that the age-related decline in sperm viability was contingent on male sexual ornamentation; males with relatively high levels of iridescence (indicating higher sexual attractiveness) exhibited a more pronounced decline in sperm viability over time than their less ornamented counterparts. This latter finding offers possible insights into the functional basis for the previously observed trade-off between these key components of pre- and postcopulatory sexual selection.
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Mirror, mirror on the wall…: self-perception of facial beauty versus judgement by others.
Springer, I N; Wiltfang, J; Kowalski, J T; Russo, P A J; Schulze, M; Becker, S; Wolfart, S
2012-12-01
In 1878, Margaret Wolfe Hungerford published a simple but insightful phrase in her novel 'Molly Bawn' that was to be quoted so often it has almost become cliché: "Beauty is in the eye of the beholder". While many questions regarding the perception and neural processing of facial attractiveness have been resolved, it became obvious to us that study designs have been principally based on either facial self-perception or perception by others. The relationship between these however, remains both crucial and unknown. Standardized images were taken of 141 subjects. These 141 subjects were asked to complete the adjective mood scale (AMS) and to rank specific issues related to their looks on a visual analogue scale. The images were then shown to independent judges to rank specific issues related to their looks on a visual analogue scale. Our results show proof for a strikingly simple observation: that individuals perceive their own beauty to be greater than that expressed in the opinions of others (p < 0.001). This observation provides insight into our basic behavioural patterns and suggests that there are strong psychological mechanisms in humans supporting self-identification and thereby encouraging the self-confidence and resilience necessary to maintain one's social standing. While the psychological basis of self-confidence is multifactorial, our finding provides critical objective insight. We prove here for the first time that nothing more than the beauty of the beholder is in the eyes of the latter. Copyright © 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
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Mattsson, Monte; Hood, Glen R; Feder, Jeffrey L; Ruedas, Luis A
2015-12-01
Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonella fruit flies in eastern North America underwent a host shift ~160 ya from native downy hawthorn (Crataegus mollis) to introduced, domesticated apple (Malus domestica). Divergent selection on diapause phenology related to the earlier fruiting time of apples versus downy hawthorns resulted in partial allochronic reproductive isolation between the fly races. Here, we test for how rapid and repeatable shifts in life-history timing are driving ecological divergence of R. pomonella in the Pacific Northwestern USA. The fly was introduced into the region via larval-infested apples 40-65 ya and now attacks native black hawthorn (Crataegus douglasii) and introduced ornamental hawthorn (Crataegus monogyna), in addition to early- and late-maturing apple varieties in the region. To investigate the life-history timing hypothesis, we used a field-based experiment to characterize the host-associated eclosion and flight activity patterns of adults, and the feeding times of larvae at a field site in Vancouver, Washington. We also assessed the degree to which differences in host-fruiting time generate allochronic isolation among apple-, black hawthorn-, and ornamental hawthorn-associated fly populations. We conclude that host-associated fly populations are temporally offset 24.4% to 92.6% in their seasonal distributions. Our results imply that R. pomonella possesses the capacity for rapid and repeatable shifts in diapause life history to match host-fruiting phenology, which can generate ecologically based reproductive isolation, and potentially biodiversity in the process.
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2009-01-01
Background Gastric cancer is decreasing in most countries. While socioeconomic development is the main factor to which this decline has been attributed, enormous differences among countries and within regions are still observed, with the main contributing factors remaining elusive. This study describes the geographic distribution of gastric cancer mortality at a municipal level in Spain, from 1994-2003. Methods Smoothed relative risks of stomach cancer mortality were obtained, using the Besag-York-Molliè autoregressive spatial model. Maps depicting relative risk (RR) estimates and posterior probabilities of RR being greater than 1 were plotted. Results From 1994-2003, 62184 gastric cancer deaths were registered in Spain (7 percent of all deaths due to malignant tumors). The geographic pattern was similar for both sexes. RRs displayed a south-north and coast-inland gradient, with lower risks being observed in Andalusia, the Mediterranean coastline, the Balearic and Canary Islands and the Cantabrian seaboard. The highest risk was concentrated along the west coast of Galicia, broad areas of the Castile & Leon Autonomous community, the province of Cáceres in Extremadura, Lleida and other areas of Catalonia. Conclusion In Spain, risk of gastric cancer mortality displays a striking geographic distribution. With some differences, this persistent and unique pattern is similar across the sexes, suggesting the implication of environmental exposures from sources, such as diet or ground water, which could affect both sexes and delimited geographic areas. Also, the higher sex-ratios found in some areas with high risk of smoking-related cancer mortality in males support the role of tobacco in gastric cancer etiology. PMID:19737377
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Bahadır Acikara, Özlem; Hošek, Jan; Babula, Petr; Cvačka, Josef; Budešínský, Miloš; Dračinský, Martin; Saltan İşcan, Gülçin; Kadlecová, Daniela; Ballová, Ludmila; Šmejkal, Karel
2015-12-30
Scorzonera species are used in different folk medicines to combat many diseases, including the illnesses connected with inflammation. Previous experiments showed anti-inflammatory activity of Scorzonera extracts in vivo. S. latifolia, S. cana var. jacquiniana, S. tomentosa, S. mollis ssp. szowitsii, S. eriophora, S. incisa, S. cinerea, and S. parviflora extracts were, therefore, evaluated for their inhibitory activities of TNF-α and IL-1β production, and NF-κB nuclear translocation in THP-1 macrophages. The HPLC analysis was carried out to elucidate and to compare the composition of these extracts. Major compounds of the tested extracts have been isolated using different chromatographic techniques and further tested for their inhibitory activities on TNF-α and IL-1β production. Several extracts showed promising anti-inflammatory activity in these in vitro tests. Results of HPLC analysis revealed chlorogenic acid as a compound present in all tested extracts. Hyperoside, quercetin-3-O-β-d-glucoside and rutin were also present in varying amount in some Scorzonera species analyzed. Furthermore, eight phenolics which were identified as quercetin-3-O-β-d-glucoside (1), hyperoside (2), hydrangenol-8-O-glucoside (3), swertisin (4), 7-methylisoorientin (5), 4,5-O-dicaffeoyl-quinic acid (6), 3,5-di-O-caffeoyl-quinic acid (7), and chlorogenic acid (8) have been isolated as major phenolic compounds of the tested extracts and, together with eight terpenoids (9-16) previously obtained from different Scorzonera species, have been tested for the inhibition of TNF-α production, unfortunately with no activity comparable with standard.
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Hair Testing for Drugs of Abuse and New Psychoactive Substances in a High-Risk Population.
Salomone, Alberto; Palamar, Joseph J; Gerace, Enrico; Di Corcia, Daniele; Vincenti, Marco
2017-06-01
Hundreds of new psychoactive substances (NPS) have emerged in the drug market over the last decade. Few drug surveys in the USA, however, ask about use of NPS, so prevalence and correlates of use are largely unknown. A large portion of NPS use is unintentional or unknown as NPS are common adulterants in drugs like ecstasy/Molly, and most NPS are rapidly eliminated from the body, limiting efficacy of urine, blood and saliva testing. We utilized a novel method of examining prevalence of NPS use in a high-risk population utilizing hair-testing. Hair samples from high-risk nightclub and dance music attendees were tested for 82 drugs and metabolites (including NPS) using ultra-high performance liquid chromatography-tandem mass spectrometry. Eighty samples collected from different parts of the body were analyzed, 57 of which detected positive for at least one substance-either a traditional or new drug. Among these, 26 samples tested positive for at least one NPS-the most common being butylone (25 samples). Other new drugs detected include methylone, methoxetamine, 5/6-APB, α-PVP and 4-FA. Hair analysis proved a powerful tool to gain objective biological drug-prevalence information, free from possible biases of unintentional or unknown intake and untruthful reporting of use. Such testing can be used actively or retrospectively to validate survey responses and inform research on consumption patterns, including intentional and unknown use, polydrug-use, occasional NPS intake and frequent or heavy use. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Sampling animal sign in heterogeneous environments: how much is enough?
Holbrook, Joseph D.; Arkle, Robert S.; Rachlow, Janet L.; Vierling, Kerri T.; Pilliod, David S.
2015-01-01
Animal ecologists often use animal sign as a surrogate for direct observation of organisms, especially when species are secretive or difficult to observe. Spatial heterogeneity in arid environments makes it challenging to consistently detect and precisely characterize animal sign, which can bias estimates of animal abundance or habitat use. Piute ground squirrels (Urocitellus mollis) and Owyhee harvester ants (Pogonomyrmex salinus) live in arid environments and are fossorial, which can make them difficult to observe directly. Their relative abundance can be assessed using sign (i.e., burrows and nests). We implemented an over-sampling framework (i.e., recorded an excessive amount of information) with two observers to 1) identify a sampling intensity that balanced precision with our resource constraints, and 2) assess classification and detection of squirrel burrows and ant nests across vegetation conditions. We sampled 20 1-ha plots for ground squirrel burrows and ant nests using six 4 m × 100 m belt transects. Analyses of precision and sampling effort indicated that three belt transects covering 1200 m2 per ha provided sufficient precision, while minimizing effort. Regardless of vegetation conditions, counts by two observers were strongly correlated for ground squirrel burrows (r = 0.99, P < 0.001, df = 18; slope = 0.92) and harvester ant nests (r = 0.99, P < 0.001, df = 18; slope = 1.01) indicating observer consistency and perhaps high detection probability. These findings illustrate an approach for evaluating sampling designs in many ecological contexts.
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MR fingerprinting for rapid quantification of myocardial T1 , T2 , and proton spin density.
Hamilton, Jesse I; Jiang, Yun; Chen, Yong; Ma, Dan; Lo, Wei-Ching; Griswold, Mark; Seiberlich, Nicole
2017-04-01
To introduce a two-dimensional MR fingerprinting (MRF) technique for quantification of T 1 , T 2 , and M 0 in myocardium. An electrocardiograph-triggered MRF method is introduced for mapping myocardial T 1 , T 2 , and M 0 during a single breath-hold in as short as four heartbeats. The pulse sequence uses variable flip angles, repetition times, inversion recovery times, and T 2 preparation dephasing times. A dictionary of possible signal evolutions is simulated for each scan that incorporates the subject's unique variations in heart rate. Aspects of the sequence design were explored in simulations, and the accuracy and precision of cardiac MRF were assessed in a phantom study. In vivo imaging was performed at 3 Tesla in 11 volunteers to generate native parametric maps. T 1 and T 2 measurements from the proposed cardiac MRF sequence correlated well with standard spin echo measurements in the phantom study (R 2 > 0.99). A Bland-Altman analysis revealed good agreement for myocardial T 1 measurements between MRF and MOLLI (bias 1 ms, 95% limits of agreement -72 to 72 ms) and T 2 measurements between MRF and T 2 -prepared balanced steady-state free precession (bias, -2.6 ms; 95% limits of agreement, -8.5 to 3.3 ms). MRF can provide quantitative single slice T 1 , T 2 , and M 0 maps in the heart within a single breath-hold. Magn Reson Med 77:1446-1458, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.
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Araújo, Cristiano V M; Silva, Daniel C V R; Gomes, Luiz E T; Acayaba, Raphael D; Montagner, Cassiana C; Moreira-Santos, Matilde; Ribeiro, Rui; Pompêo, Marcelo L M
2018-02-01
Information on how atrazine can affect the spatial distribution of organisms is non-existent. As this effect has been observed for some other contaminants, we hypothesized that atrazine-containing leachates/discharges could trigger spatial avoidance by the fish Poecilia reticulata and form a chemical barrier isolating upstream and downstream populations. Firstly, guppies were exposed to an atrazine gradient in a non-forced exposure system, in which organisms moved freely among the concentrations, to assess their ability to avoid atrazine. Secondly, a chemical barrier formed by atrazine, separating two clean habitats (extremities of the non-forced system), was simulated to assess whether the presence of the contaminant could prevent guppies from migrating to the other side of the system. Fish were able to avoid atrazine contamination at environmentally relevant concentrations (0.02 μg L -1 ), below those described to cause sub-lethal effects. The AC 50 (atrazine concentration causing avoidance to 50% of the population) was 0.065 μg L -1 . The chemical barrier formed by atrazine at 150 μg L -1 (concentration that should produce an avoidance around 82%) caused a reduction in the migratory potential of the fish by 47%; while the chemical barrier at 1058 μg L -1 (concentration that produces torpidity) caused a reduction in the migratory potential of the fish by 91%. Contamination by atrazine, besides driving the spatial distribution of fish populations, has potential to act as a chemical barrier by isolating fish populations. This study includes a novel approach to be integrated in environmental risk assessment schemes to assess high-tier contamination effects such as habitat fragmentation and population displacement and isolation. Copyright © 2017 Elsevier Ltd. All rights reserved.
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The genetic basis of female multiple mating in a polyandrous livebearing fish
Evans, Jonathan P; Gasparini, Clelia
2013-01-01
The widespread occurrence of female multiple mating (FMM) demands evolutionary explanation, particularly in the light of the costs of mating. One explanation encapsulated by “good sperm” and “sexy-sperm” (GS-SS) theoretical models is that FMM facilitates sperm competition, thus ensuring paternity by males that pass on genes for elevated sperm competitiveness to their male offspring. While support for this component of GS-SS theory is accumulating, a second but poorly tested assumption of these models is that there should be corresponding heritable genetic variation in FMM – the proposed mechanism of postcopulatory preferences underlying GS-SS models. Here, we conduct quantitative genetic analyses on paternal half-siblings to test this component of GS-SS theory in the guppy (Poecilia reticulata), a freshwater fish with some of the highest known rates of FMM in vertebrates. As with most previous quantitative genetic analyses of FMM in other species, our results reveal high levels of phenotypic variation in this trait and a correspondingly low narrow-sense heritability (h2 = 0.11). Furthermore, although our analysis of additive genetic variance in FMM was not statistically significant (probably owing to limited statistical power), the ensuing estimate of mean-standardized additive genetic variance (IA = 0.7) was nevertheless relatively low compared with estimates published for life-history traits across a broad range of taxa. Our results therefore add to a growing body of evidence that FMM is characterized by relatively low additive genetic variation, thus apparently contradicting GS-SS theory. However, we qualify this conclusion by drawing attention to potential deficiencies in most designs (including ours) that have tested for genetic variation in FMM, particularly those that fail to account for intersexual interactions that underlie FMM in many systems. PMID:23403856
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Rahman, Md. Moshiur; Turchini, Giovanni M.; Gasparini, Clelia; Norambuena, Fernando; Evans, Jonathan P.
2014-01-01
Environmental and ecological conditions can shape the evolution of life history traits in many animals. Among such factors, food or nutrition availability can play an important evolutionary role in moderating an animal's life history traits, particularly sexually selected traits. Here, we test whether diet quantity and/or composition in the form of omega-3 long chain polyunsaturated fatty acids (here termed ‘n3LC’) influence the expression of pre- and postcopulatory traits in the guppy (Poecilia reticulata), a livebearing poeciliid fish. We assigned males haphazardly to one of two experimental diets supplemented with n3LC, and each of these diet treatments was further divided into two diet ‘quantity’ treatments. Our experimental design therefore explored the main and interacting effects of two factors (n3LC content and diet quantity) on the expression of precopulatory (sexual behaviour and sexual ornamentation, including the size, number and spectral properties of colour spots) and postcopulatory (the velocity, viability, number and length of sperm) sexually selected traits. Our study revealed that diet quantity had significant effects on most of the pre- and postcopulatory traits, while n3LC manipulation had a significant effect on sperm traits and in particular on sperm viability. Our analyses also revealed interacting effects of diet quantity and n3LC levels on courtship displays, and the area of orange and iridescent colour spots in the males’ colour patterns. We also confirmed that our dietary manipulations of n3LC resulted in the differential uptake of n3LC in body and testes tissues in the different n3LC groups. This study reveals the effects of diet quantity and n3LC on behavioural, ornamental and ejaculate traits in P. reticulata and underscores the likely role that diet plays in maintaining the high variability in these condition-dependent sexual traits. PMID:25170940
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No evidence for sperm priming responses under varying sperm competition risk or intensity in guppies
NASA Astrophysics Data System (ADS)
Evans, Jonathan P.
2009-07-01
Sperm competition theory predicts that males should tailor their investment in ejaculates according to the number of rival males competing to fertilize a female’s eggs. Research spanning several taxa supports this prediction by showing that males are often sensitive to the level of sperm competition and adjust their investment in sperm numbers accordingly. More recent work has revealed that males may also tailor the quality of sperm according to the number of males competing for fertilization. Here I test for both effects in guppies ( Poecilia reticulata) in an experiment that simultaneously evaluates the risk and intensity models of sperm competition. The experiment determined whether male guppies adjust the number (stripped ejaculate size) and quality (sperm velocity and viability) of sperm that are primed over a 3-day period according to experimental changes in the perceived level of sperm competition. A total of 136 focal males were initially stripped of all retrievable sperm and assayed for these sperm traits before being allocated at random to one of four treatments simulating different levels of sperm competition risk and intensity. During the 3-day treatment phase, focal males had visual and olfactory access to a sexually receptive (initially virgin) female maintained with different numbers of stimulus males to simulate variation in the risk and intensity of sperm competition. Following this, males were assayed again for the sperm traits. Contrary to predictions, there was no significant change in any of the measured variables among treatments, although qualitatively the patterns for sperm velocity and viability did conform to expectation. The lack of any trend for the number of sperm primed was unequivocal and future work examining the effects of sperm competition on sperm production should focus on whether males differentially allocate sperm numbers among matings that differ in the level of sperm competition.
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Krizkova, Sona; Krystofova, Olga; Trnkova, Libuse; Hubalek, Jaromir; Adam, Vojtech; Beklova, Miroslava; Horna, Ales; Havel, Ladislav; Kizek, Rene
2009-01-01
We used carbon paste electrodes and a standard potentiostat to detect silver ions. The detection limit (3 Signal/Noise ratio) was estimated as 0.5 μM. A standard electrochemical instrument microanalysis of silver(I) ions was suggested. As a working electrode a carbon tip (1 mL) or carbon pencil was used. Limits of detection estimated by dilution of a standard were 1 (carbon tip) or 10 nM (carbon pencil). Further we employed flow injection analysis coupled with carbon tip to detect silver(I) ions released in various beverages and mineral waters. During first, second and third week the amount of silver(I) ions releasing into water samples was under the detection limit of the technique used for their quantification. At the end of a thirteen weeks long experiment the content of silver(I) ions was several times higher compared to the beginning of release detected in the third week and was on the order of tens of nanomoles. In subsequent experiments the influence of silver(I) ions (0, 5 and 10 μM) on a plant model system (tobacco BY-2 cells) during a four-day exposition was investigated. Silver(I) ions were highly toxic to the cells, which was revealed by a double staining viability assay. Moreover we investigated the effect of silver(I) ions (0, 0.3, 0.6, 1.2 and 2.5 μM) on guppies (Poecilia reticulata). Content of Ag(I) increased with increasing time of the treatment and applied concentrations in fish tissues. It can be concluded that a carbon tip or carbon pencil coupled with a miniaturized potentiostat can be used for detection of silver(I) ions in environmental samples and thus represents a small, portable, low cost and easy-to-use instrument for such purposes. PMID:22399980
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Influence of interspecific interactions on avoidance response to contamination.
Silva, Daniel C V R; Araújo, Cristiano V M; Marassi, Rodrigo J; Cardoso-Silva, Sheila; Neto, Morun B; Silva, Gilmar C; Ribeiro, Rui; Silva, Flávio T; Paiva, Teresa C B; Pompêo, Marcelo L M
2018-06-17
An increasing number of studies have shown the ability of organisms to escape from toxic effects due to contamination, by moving spatially towards less contaminated habitats. However, this issue has been investigated in monospecific scenarios, without considering possible interactions between species during the contamination avoidance process. It is widely known that the spatial distribution of one species can be affected by another one, in different ways. Therefore, the main question addressed in the present study was as follows: Might interspecific interaction between the freshwater fish Danio rerio (zebrafish) and Poecilia reticulata (guppy) change their behavior patterns in terms of avoidance in the presence of a copper gradient? Zebrafish and guppies exposed to a copper gradient were tested for avoidance responses in a free-choice, non-forced, static, multi-compartmented exposure system, using two distinct approaches: (1) monospecific tests, in which only one species was exposed to the copper gradient, at two different population densities; and (2) multispecific tests, in which both species were tested simultaneously. In the control (with no copper) monospecific tests, both species were randomly distributed; however, in the control multispecific test, P. reticulata tended to aggregate. In the monospecific tests with a copper gradient, both species avoided copper in a similar way, with AC 50 (concentration triggering avoidance in 50% of the exposed population) values between 15 and 18 μg·L -1 , irrespective of the population density. However, in the multispecific tests, P. reticulata displaced D. rerio to previously avoided copper levels, consequently increasing the AC 50 of D. rerio to 75 μg·L -1 . This study shows the importance of understanding the interactions among species in contaminated areas, and the way that one species can prevent the avoidance behavior of another. Copyright © 2018 Elsevier B.V. All rights reserved.
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Zukoshi, Reo; Savelli, Ilaria; Novales Flamarique, Iñigo
2018-04-01
Many vertebrates have cone photoreceptors that are most sensitive to ultraviolet (UV) light termed UV cones. The ecological functions that these cones contribute to are seldom known though they are suspected of improving foraging and communication in a variety of fishes. In this study, we used several spectral backgrounds to assess the contribution of UV and violet cones, or long wavelength (L) cones, in the foraging performance of juvenile Cumaná guppy, Poecilia reticulata, or marine stickleback, Gasterosteus aculeatus. Regardless of whether the light spectrum contained or not wavelengths below 450 nm (the limiting wavelength for UV cone stimulation), the foraging performance of both species was statistically the same, as judged by the mean distance and angle associated with attacks on prey (Daphnia magna). Our experiments also showed that the foraging performance of sticklebacks when only the double cones (and, almost exclusively, the L cones) were active was similar to that when all cones were functional, demonstrating that the double cone was sufficient for prey detection. This result indicates that foraging potentially relied on an achromatic channel serving prey motion detection, as the two spectral cone types that make up the double cone [maximally sensitive to middle (M) and long (L) wavelengths, respectively] form the input to the achromatic channel in cyprinid fishes and double cones are widely associated with achromatic tasks in other vertebrates including reptiles and birds. Stickleback performance was also substantially better when foraging under a 100% linearly polarized light field than when under an unpolarized light field. Together, our results suggest that in some teleost species UV cones exert visually-mediated ecological functions different from foraging, and furthermore that polarization sensitivity could improve the foraging performance of sticklebacks. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Ejbye-Ernst, Rasmus; Michaelsen, Thomas Y.; Tirsgaard, Bjørn; Wilson, Jonathan M.; Jensen, Lasse F.; Steffensen, John F.; Pertoldi, Cino; Aarestrup, Kim; Svendsen, Jon C.
2016-01-01
Ongoing climate change is predicted to affect the distribution and abundance of aquatic ectotherms owing to increasing constraints on organismal physiology, in particular involving the metabolic scope (MS) available for performance and fitness. The oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis prescribes MS as an overarching benchmark for fitness-related performance and assumes that any anaerobic contribution within the MS is insignificant. The MS is typically derived from respirometry by subtracting standard metabolic rate from the maximal metabolic rate; however, the methodology rarely accounts for anaerobic metabolism within the MS. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), this study tested for trade-offs (i) between aerobic and anaerobic components of locomotor performance; and (ii) between the corresponding components of the MS. Data collection involved measuring oxygen consumption rate at increasing swimming speeds, using the gait transition from steady to unsteady (burst-assisted) swimming to detect the onset of anaerobic metabolism. Results provided evidence of the locomotor performance trade-off, but only in S. aurata. In contrast, both species revealed significant negative correlations between aerobic and anaerobic components of the MS, indicating a trade-off where both components of the MS cannot be optimized simultaneously. Importantly, the fraction of the MS influenced by anaerobic metabolism was on average 24.3 and 26.1% in S. aurata and P. reticulata, respectively. These data highlight the importance of taking anaerobic metabolism into account when assessing effects of environmental variation on the MS, because the fraction where anaerobic metabolism occurs is a poor indicator of sustainable aerobic performance. Our results suggest that without accounting for anaerobic metabolism within the MS, studies involving the OCLTT hypothesis could overestimate the metabolic scope available for
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Non-adaptive plasticity potentiates rapid adaptive evolution of gene expression in nature.
Ghalambor, Cameron K; Hoke, Kim L; Ruell, Emily W; Fischer, Eva K; Reznick, David N; Hughes, Kimberly A
2015-09-17
Phenotypic plasticity is the capacity for an individual genotype to produce different phenotypes in response to environmental variation. Most traits are plastic, but the degree to which plasticity is adaptive or non-adaptive depends on whether environmentally induced phenotypes are closer or further away from the local optimum. Existing theories make conflicting predictions about whether plasticity constrains or facilitates adaptive evolution. Debate persists because few empirical studies have tested the relationship between initial plasticity and subsequent adaptive evolution in natural populations. Here we show that the direction of plasticity in gene expression is generally opposite to the direction of adaptive evolution. We experimentally transplanted Trinidadian guppies (Poecilia reticulata) adapted to living with cichlid predators to cichlid-free streams, and tested for evolutionary divergence in brain gene expression patterns after three to four generations. We find 135 transcripts that evolved parallel changes in expression within the replicated introduction populations. These changes are in the same direction exhibited in a native cichlid-free population, suggesting rapid adaptive evolution. We find 89% of these transcripts exhibited non-adaptive plastic changes in expression when the source population was reared in the absence of predators, as they are in the opposite direction to the evolved changes. By contrast, the remaining transcripts exhibiting adaptive plasticity show reduced population divergence. Furthermore, the most plastic transcripts in the source population evolved reduced plasticity in the introduction populations, suggesting strong selection against non-adaptive plasticity. These results support models predicting that adaptive plasticity constrains evolution, whereas non-adaptive plasticity potentiates evolution by increasing the strength of directional selection. The role of non-adaptive plasticity in evolution has received relatively
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Exploring Spatial Patterns of Colorectal Cancer in Tehran City, Iran
Mansori, Kamyar; Mosavi-Jarrahi, Alireza; Ganbary Motlagh, Ali; Solaymani-Dodaran, Masoud; Salehi, Masoud; Delavari, Alireza; Sanjari Moghaddam, Ali; Asadi-Lari, Mohsen
2018-04-27
Objectives: Colorectal cancer (CRC) may now be the second most common cancer in the world. The aim of this study was to determine whether clusters of high and low risk of CRC might exist at the neighborhood level in Tehran city. Methods: In this study, new cases of CRC provided from Cancer Registry Data of the Management Center of Ministry of Health and Medical Education of Iran in the period from March 2008 to March 2011 were analyzed. Raw standardized incidence rates (SIRs) were calculated for CRC in each neighborhood, along with ratios of observed to expected cases. The York and Mollie (BYM) spatial model was used for smoothing of the estimated raw SIRs. To discover clusters of high and low CRC incidence a purely spatial scan statistic was applied. Results: A total of 2,815 new cases of CRC were identified and after removal of duplicate cases, 2,491 were geocoded to neighborhoods. The locations with higher than expected incidence of CRC were northern and central districts of Tehran city. An observed to expected ratio of 2.57 (p<0.001) was found for districts of 2, 6 and 11, whereas, the lowest ratio of 0.23 (p<0.001) was apparent for northeast and south areas of the city, including district 4. Conclusions: This study showed that there is a significant spatial variation in patterns of incidence of CRC at the neighborhood level in Tehran city. Identification of such spatial patterns and assessment of underlying risk factors can provide valuable information for policymakers responsible for equitable distribution of healthcare resources. Creative Commons Attribution License
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del Canto, M; García-Martínez, L; Fernández-Villa, T; Molina, A J; Campanario, F; García-Sanz, M; López-Abente, G; Honrado, E; Martín-Sánchez, V
2015-01-01
Spain is a country where bladder cancer incidence and mortality rates are some of the highest in the world. The aim of this study is to know the incidence, trends and geographical distribution of bladder cancer in the health area of León. the new cases of bladder cancer (CIE-188) in patients residing in the health area of León and registered in the Hospital Tumor Registry of the Centro Asistencial Universitario in León (Spain) between 1996-2010 were included in this study. Triennial crude incidence and adjusted incidence rates to the worldwide and European population were calculated. Population data of the municipalities of Leon (Spain) were obtained from National Institute of Statistic of Spain (INE, Instituto Nacional de Estadística). Data were disaggregated by sex-groups and five-year age groups. Spatial distribution of smoothed municipal relative risks (RR) of bladder cancer was carried out using a Besag, York and Mollié model. Bayesian model were used to calculate the posterior probability (PP) of RR greater than one. 1.573 cases were included. Incidence rates standardized to European population increased among men from 20,8/100.000 (1996-98) to 33,1/100.000 (2006-2008) and among women these rates increased from 1,9/100.000 to 5,9/100.000 for the same period of time. No relevant differences were found in the municipal distribution of the incidences. bladder cancer incidence rates are high in the European context. Rising trends in incidence in both sexs, particularly in women are observed. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.
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Palamar, Joseph J.; Acosta, Patricia; Ompad, Danielle C.; Cleland, Charles M.
2016-01-01
Background Ecstasy (MDMA) use has regained popularity in the United States, particularly in the form of “Molly,” which is often marketed as pure MDMA. Surveys have generally not included “Molly” in the definition of ecstasy, so rates of use may be underestimated. As popularity of ecstasy increases, research is needed to examine use among those at highest risk for use—nightlife attendees. Methods We surveyed 679 young adults (age 18–25) entering nightclubs and festivals holding electronic dance music (EDM) parties in New York City in 2015. A variation of time-space sampling was utilized. We examined prevalence and correlates of self-reported lifetime ecstasy use. Results Self-reported lifetime ecstasy use was common (42.8%, 95% CI: 32.8, 52.7). Use was most common among older participants, frequent party attendees, and those reporting higher levels of exposure to users. Those surveyed outside of festivals were less likely to report use compared to those surveyed outside of nightclubs (AOR=0.37, p = .015). Over a third of ecstasy users (36.8%) reported use in pill, powder, and crystal form. Ecstasy users were also more likely to report use of other drugs, including novel psychoactive substances (e.g., 2C series drugs, synthetic cathinones [“bath salts”]). Half (50.4%) reported suspecting (21.9%) or finding out (28.5%) that their ecstasy had ever contained a drug other than MDMA. Conclusion A large percentage of nightlife attendees in NYC report lifetime ecstasy use. Findings should inform prevention and harm reduction programming. Further research is needed as ecstasy continues to change (e.g., in form, purity, and name). PMID:27661470
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Gandarillas, A M; Domínguez-Berjón, M F; Soto, M J
2016-06-01
This study sought to describe the total mortality trend by socioeconomic deprivation (SED) in the Madrid Autonomous Region, by sex and age group. Cross-sectional ecological study by census tract, in two periods: 1994-2000 (P1) with SED of 1996 census and 2001-07 (P2) with SED of 2001 census. We calculated the relative risks (RRs) and their 95% credibility intervals (95% CIs) by SED quintile (Q), taking the quintile of least deprivation as reference. Besag-York-Mollié ecological regression models and the Integrated Nested Laplace Approximation procedure were applied. The absolute differences in age-standardized rates were compared by SED quintile. Inequalities decreased in young adults: among men aged 20-39 years, the RR in Q5 versus Q1 ranged from 2.73 (95% CI, 2.51-3.02) in P1 to 1.93 (95% CI, 1.76-2.15) in P2, due to the greater improvement in the most underprivileged groups. In contrast, there was an increase in SED-related mortality in the 40-79 age group. Among men aged 40-59 years, the RR in Q5 versus Q1 rose from 1.88 (95% CI, 1.76-2.02) in P1 to 2.29 (95% CI, 2.17-2.43) in P2; the improvement was greater in the most privileged groups. In a context of an economic boom, inequalities were observed to increase among adults by a greater improvement in the most privileged groups. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Haggerty, Christopher M; Suever, Jonathan D; Pulenthiran, Arichanah; Mejia-Spiegeler, Abba; Wehner, Gregory J; Jing, Linyuan; Charnigo, Richard J; Fornwalt, Brandon K; Fogel, Mark A
2017-12-11
Patients with repaired tetralogy of Fallot (TOF) have progressive, adverse biventricular remodeling, leading to abnormal contractile mechanics. Defining the mechanisms underlying this dysfunction, such as diffuse myocardial fibrosis, may provide insights into poor long-term outcomes. We hypothesized that left ventricular (LV) diffuse fibrosis is related to impaired LV mechanics. Patients with TOF were evaluated with cardiac magnetic resonance in which modified Look-Locker (MOLLI) T1-mapping and spiral cine Displacement encoding (DENSE) sequences were acquired at three LV short-axis positions. Linear mixed modeling was used to define the association between regional LV mechanics from DENSE based on regional T1-derived diffuse fibrosis measures, such as extracellular volume fraction (ECV). Forty patients (26 ± 11 years) were included. LV ECV was generally within normal range (0.24 ± 0.05). For LV mechanics, peak circumferential strains (-15 ± 3%) and dyssynchrony indices (16 ± 8 ms) were moderately impaired, while peak radial strains (29 ± 8%) were generally normal. After adjusting for patient age, sex, and regional LV differences, ECV was associated with log-adjusted LV dyssynchrony index (β = 0.67) and peak LV radial strain (β = -0.36), but not LV circumferential strain. Moreover, post-contrast T1 was associated with log-adjusted LV diastolic circumferential strain rate (β = 0.37). We observed several moderate associations between measures of fibrosis and impaired mechanics, particularly the LV dyssynchrony index and peak radial strain. Diffuse fibrosis may therefore be a causal factor in some ventricular dysfunction in TOF.
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Palamar, Joseph J.; Salomone, Alberto; Vincenti, Marco; Cleland, Charles M.
2016-01-01
Background Ecstasy (MDMA) in the US is commonly adulterated with other drugs, but research has not focused on purity of ecstasy since the phenomenon of “Molly” (ecstasy marketed as pure MDMA) arose in the US. Methods We piloted a rapid electronic survey in 2015 to assess use of novel psychoactive substances (NPS) and other drugs among 679 nightclub/festival-attending young adults (age 18–25) in New York City. A quarter (26.1%) of the sample provided a hair sample to be analyzed for the presence of select synthetic cathinones (“bath salts”) and some other NPS. Samples were analyzed using fully validated UHPLC-MS/MS methods. To examine consistency of self-report, analyses focused on the 48 participants with an analyzable hair sample who reported lifetime ecstasy/MDMA/Molly use. Results Half (50.0%) of the hair samples contained MDMA, 47.9% contained butylone, and 10.4% contained methylone. Of those who reported no lifetime use of “bath salts”, stimulant NPS, or unknown pills or powders, about four out of ten (41.2%) tested positive for butylone, methylone, alpha-PVP, 5/6-APB, or 4-FA. Racial minorities were more likely to test positive for butylone or test positive for NPS after reporting no lifetime use. Frequent nightclub/festival attendance was the strongest predictor of testing positive for MDMA, butylone, or methylone. Discussion Results suggest that many ecstasy-using nightclub/festival attendees may be unintentionally using “bath salts” or other NPS. Prevention and harm reduction education is needed for this population and “drug checking” (e.g., pill testing) may be beneficial for those rejecting abstinence. PMID:26883685
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PA6 Death chat: engaging with dying and death.
Goodhead, Andrew; Hartley, Nigel
2015-04-01
Talking about death continues to be a social taboo. St Christopher's has a large, welcoming social space, (The Anniversary Centre) and is committed to opening up its buildings in a number of ways. The St Christopher's social programme, of which Death Chat is part, aims to break down social taboos. Hospices have a responsibility to engage creatively with patients, family members, carers and the wider community. Death Chat, held in the hospice buildings, enables honest discussion about dying and death and topics surrounding these themes. Death Chat meets weekly and is an open meeting that takes a different subject each week as the starting point for conversation. Cheese and wine are shared and participants quickly find a place in the group. Death Chat has attracted patients, family members, bereaved relatives and the community since September 2013. Attendees have reflected that coming has broken taboos. Peter said, 'it's nowhere near as depressing as it sounds; it's a nice, friendly atmosphere - a convivial place.' Molly found Death Chat to be a welcoming, open and challenging space, 'I have learnt that death is more about my attitude to life than anything else. It has been by far the most important lesson I have learnt since dealing with bereavement.' Death Chat provides a forum in which discussion of dying and death for recognises that these are social events and reclaims them from being taboo, to being a normal part of life's experience. © 2015, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
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Edet, Offiong Ukpong; Kim, June-Sik; Okamoto, Masanori; Hanada, Kousuke; Takeda, Tomoyuki; Kishii, Masahiro; Gorafi, Yasir Serag Alnor; Tsujimoto, Hisashi
2018-03-27
The tertiary gene pool of bread wheat, to which Leymus racemosus belongs, has remained underutilized due to the current limited genomic resources of the species that constitute it. Continuous enrichment of public databases with useful information regarding these species is, therefore, needed to provide insights on their genome structures and aid successful utilization of their genes to develop improved wheat cultivars for effective management of environmental stresses. We generated de novo DNA and mRNA sequence information of L. racemosus and developed 110 polymorphic PCR-based markers from the data, and to complement the PCR markers, DArT-seq genotyping was applied to develop additional 9990 SNP markers. Approximately 52% of all the markers enabled us to clearly genotype 22 wheat-L. racemosus chromosome introgression lines, and L. racemosus chromosome-specific markers were highly efficient in detailed characterization of the translocation and recombination lines analyzed. A further analysis revealed remarkable transferability of the PCR markers to three other important Triticeae perennial species: L. mollis, Psathyrostachys huashanica and Elymus ciliaris, indicating their suitability for characterizing wheat-alien chromosome introgressions carrying chromosomes of these genomes. The efficiency of the markers in characterizing wheat-L. racemosus chromosome introgression lines proves their reliability, and their high transferability further broadens their scope of application. This is the first report on sequencing and development of markers from L. racemosus genome and the application of DArT-seq to develop markers from a perennial wild relative of wheat, marking a paradigm shift from the seeming concentration of the technology on cultivated species. Integration of these markers with appropriate cytogenetic methods would accelerate development and characterization of wheat-alien chromosome introgression lines.
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MDMA: a social drug in a social context.
Kirkpatrick, Matthew G; de Wit, Harriet
2015-03-01
The drug ±3,4-methylenedioxymethamphetamine (MDMA, "ecstasy," "molly") is thought to produce prosocial effects and enhance social interaction. However, in most laboratory studies to date, the participants have been tested under nonsocial conditions, which may not simulate the effects the drug produces in more naturalistic social settings. Healthy experienced MDMA users participated in three laboratory sessions in which they received MDMA (0.5 or 1.0 mg/kg or placebo, double blind). They were randomly assigned to one of three social conditions, in which they were tested alone (solitary (SOL); N = 10), in the presence of a research assistant (research assistant present (RAP); N = 11) or in the presence of another participant who also received the drug (other participant present (OPP); N = 11). As expected, MDMA increased heart rate and blood pressure and produced positive subjective effects in all the three groups. It also increased ratings of attractiveness of another person and increased social interaction in RAP and OPP. The social context affected certain responses to the drug. The effects of MDMA were greater in the OPP condition, compared to the SOL or RAP conditions, on measures of "feel drug," "dizzy," and on cardiovascular. But responses to the drug on other measures, including social behavior, did not differ across the conditions. These findings provide some support for the idea that drugs produce greater effects when they are used in the presence of other drug users. However, the influence of the social context was modest, and it remains to be determined whether other variables related to social context would substantially alter the effects of MDMA or other drugs.
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2018-01-01
Objectives The aim of this study was to determine the factors associated with the spatial distribution of the incidence of colorectal cancer (CRC) in the neighborhoods of Tehran, Iran using Bayesian spatial models. Methods This ecological study was implemented in Tehran on the neighborhood level. Socioeconomic variables, risk factors, and health costs were extracted from the Equity Assessment Study conducted in Tehran. The data on CRC incidence were extracted from the Iranian population-based cancer registry. The Besag-York-Mollié (BYM) model was used to identify factors associated with the spatial distribution of CRC incidence. The software programs OpenBUGS version 3.2.3, ArcGIS 10.3, and GeoDa were used for the analysis. Results The Moran index was statistically significant for all the variables studied (p<0.05). The BYM model showed that having a women head of household (median standardized incidence ratio [SIR], 1.63; 95% confidence interval [CI], 1.06 to 2.53), living in a rental house (median SIR, 0.82; 95% CI, 0.71 to 0.96), not consuming milk daily (median SIR, 0.71; 95% CI, 0.55 to 0.94) and having greater household health expenditures (median SIR, 1.34; 95% CI, 1.06 to 1.68) were associated with a statistically significant elevation in the SIR of CRC. The median (interquartile range) and mean (standard deviation) values of the SIR of CRC, with the inclusion of all the variables studied in the model, were 0.57 (1.01) and 1.05 (1.31), respectively. Conclusions Inequality was found in the spatial distribution of CRC incidence in Tehran on the neighborhood level. Paying attention to this inequality and the factors associated with it may be useful for resource allocation and developing preventive strategies in atrisk areas. PMID:29397644
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Holtz, Bree E; Murray, Katharine M; Hershey, Denise D; Dunneback, Julie K; Cotten, Shelia R; Holmstrom, Amanda J; Vyas, Arpita; Kaiser, Molly K; Wood, Michael A
2017-04-19
Type 1 diabetes (T1D) afflicts approximately 154,000 people under 20 years of age. Three-quarters of adolescents are not achieving glycosylated hemoglobin (HbA1c) targets, which leads to negative health outcomes. Mobile health (mHealth), the use of technology in health, has been used successfully to improve health in many chronic conditions, including diabetes. The purpose of this study was to use patient-centered research methods to inform and improve the design and functionality of our T1D app, MyT1DHero, and to provide insight for others who are designing a health app for adolescents and parents. This study included data from focus groups with participants recruited from the Juvenile Diabetes Research Foundation (JDRF) southeast Michigan's family network. All data collected during the sessions were audio-recorded, transcribed, and coded. Four key themes were identified: (1) diabetes is unpredictable, (2) negative and frustrated communication, (3) motivations to use an app, and (4) feedback specific to our app. A patient-centered approach was used to assist in the development of an app for adolescents with T1D. Participants were satisfied with overall app design; customization, interactivity, and tangible rewards were identified as being necessary for continued use. Participants believed the app would help improve the communication between parents and adolescents. Many apps developed in the health context have not used a patient-centered design method or have seen vast improvements in health. This paper offers suggestions to others seeking to develop apps for adolescents and their parents. ©Bree E Holtz, Katharine M Murray, Denise D Hershey, Julie K Dunneback, Shelia R Cotten, Amanda J Holmstrom, Arpita Vyas, Molly K Kaiser, Michael A Wood. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 19.04.2017.
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Cha, Dong H; Yee, Wee L; Goughnour, Robert B; Sim, Sheina B; Powell, Thomas H Q; Feder, Jeffrey L; Linn, Charles E
2012-03-01
The apple maggot fly, Rhagoletis pomonella, infests apple (Malus domestica) and hawthorn species (most notably the downy hawthorn, Crataegus mollis) in the eastern USA. Evidence suggests that the fly was introduced into the western USA sometime in the last 60 years. In addition to apple, R. pomonella also infests two species of hawthorns in the western USA as major hosts: the native black hawthorn (C. douglasii) and the introduced ornamental English hawthorn, C. monogyna. Apple and downy hawthorn-origin flies in the eastern USA use volatile blends emitted from the surface of their respective ripening fruit to find and discriminate among host trees. To test whether the same is true for western flies, we used coupled gas chromatography and electroantennographic detection (GC-EAD) and developed a 7-component apple fruit blend for western apple-origin flies, an 8-component black hawthorn fruit blend for flies infesting C. douglasii, and a 9-component ornamental hawthorn blend for flies from C. monogyna. Crataegus douglasii and C. monogyna-origin flies showed similar levels of upwind directed flight to their respective natal synthetic fruit blends in flight tunnel assays compared to whole fruit adsorbent extracts, indicating that the blends contain all the behaviorally relevant fruit volatiles to induce maximal response levels. The black and ornamental hawthorn blends shared four compounds in common including 3-methylbutan-1-ol, which appears to be a key volatile for R. pomonella populations in the eastern, southern, and western USA that show a preference for fruit from different Crataegus species. However, the blends also differed from one another and from domesticated apple in several respects that make it possible that western R. pomonella flies behaviorally discriminate among fruit volatiles and form ecologically differentiated host races, as is the case for eastern apple and hawthorn flies.
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Maier, Werner; Schweikart, Jürgen; Keste, Andrea; Moskwyn, Marita
2018-01-01
Background Chronic obstructive pulmonary disease (COPD) has a high prevalence rate in Germany and a further increase is expected within the next years. Although risk factors on an individual level are widely understood, only little is known about the spatial heterogeneity and population-based risk factors of COPD. Background knowledge about broader, population-based processes could help to plan the future provision of healthcare and prevention strategies more aligned to the expected demand. The aim of this study is to analyze how the prevalence of COPD varies across northeastern Germany on the smallest spatial-scale possible and to identify the location-specific population-based risk factors using health insurance claims of the AOK Nordost. Methods To visualize the spatial distribution of COPD prevalence at the level of municipalities and urban districts, we used the conditional autoregressive Besag–York–Mollié (BYM) model. Geographically weighted regression modelling (GWR) was applied to analyze the location-specific ecological risk factors for COPD. Results The sex- and age-adjusted prevalence of COPD was 6.5% in 2012 and varied widely across northeastern Germany. Population-based risk factors consist of the proportions of insurants aged 65 and older, insurants with migration background, household size and area deprivation. The results of the GWR model revealed that the population at risk for COPD varies considerably across northeastern Germany. Conclusion Area deprivation has a direct and an indirect influence on the prevalence of COPD. Persons ageing in socially disadvantaged areas have a higher chance of developing COPD, even when they are not necessarily directly affected by deprivation on an individual level. This underlines the importance of considering the impact of area deprivation on health for planning of healthcare. Additionally, our results reveal that in some parts of the study area, insurants with migration background and persons living in
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Self-reported use of novel psychoactive substances among attendees of electronic dance music venues.
Palamar, Joseph J; Acosta, Patricia; Sherman, Scott; Ompad, Danielle C; Cleland, Charles M
2016-11-01
Novel psychoactive substances (NPSs) continue to emerge in the United States and worldwide. Few epidemiological studies have examined the prevalence and correlates of use. We examined the extent of NPS use in a high-risk population-attendees of electronic dance music (EDM) parties at nightclubs and festivals. We surveyed 682 adults (age 18-25) entering EDM events at nightclubs and festivals in New York City (NYC) in 2015. A variation of time-space sampling was used. We examined the prevalence of self-reported use of 196 NPS and correlates of any NPS use. Over a third (35.1%) of participants reported lifetime use of any NPS. Self-reported use of synthetic cannabinoids was most prevalent (16.3%), followed by psychedelic phenethylamines (14.7%; 2C series: 10.3%, 2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine [NBOMe] series: 9.0%, Dox series: 3.5%), synthetic cathinones ("bath salts", 6.9%), other psychedelics (6.6%), tryptamines (5.1%), and dissociatives (4.3%). 2C-I was the most prevalent 2C series drug (5.1%); methylone was the most prevalent synthetic cathinone (3.3%), 2-MeO-ketamine was the most prevalent dissociative (3.7%), and 1P-lysergic acid diethylamide (LSD) (2.9%) was the most prevalent non-phenethylamine psychedelic. Risk factors for NPS use included Ecstasy/MDMA/Molly, LSD, and ketamine use; identifying as bisexual (compared to heterosexual), reporting higher frequency of nightclub/festival attendance, and being surveyed outside of a festival (compared to those surveyed outside of nightclubs). NPS use is prevalent in the nightclub and festival scenes in NYC. Since individuals in these scenes-especially frequent attendees-are at high risk for use, prevention and harm reduction services need to be geared toward this population.
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Alhdiri, Maryam Ahmed; Samat, Nor Azah; Mohamed, Zulkifley
2017-01-01
Cancer is the most rapidly spreading disease in the world, especially in developing countries, including Libya. Cancer represents a significant burden on patients, families, and their societies. This disease can be controlled if detected early. Therefore, disease mapping has recently become an important method in the fields of public health research and disease epidemiology. The correct choice of statistical model is a very important step to producing a good map of a disease. Libya was selected to perform this work and to examine its geographical variation in the incidence of lung cancer. The objective of this paper is to estimate the relative risk for lung cancer. Four statistical models to estimate the relative risk for lung cancer and population censuses of the study area for the time period 2006 to 2011 were used in this work. They are initially known as Standardized Morbidity Ratio, which is the most popular statistic, which used in the field of disease mapping, Poisson-gamma model, which is one of the earliest applications of Bayesian methodology, Besag, York and Mollie (BYM) model and Mixture model. As an initial step, this study begins by providing a review of all proposed models, which we then apply to lung cancer data in Libya. Maps, tables and graph, goodness-of-fit (GOF) were used to compare and present the preliminary results. This GOF is common in statistical modelling to compare fitted models. The main general results presented in this study show that the Poisson-gamma model, BYM model, and Mixture model can overcome the problem of the first model (SMR) when there is no observed lung cancer case in certain districts. Results show that the Mixture model is most robust and provides better relative risk estimates across a range of models. PMID:28440974
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Palamar, Joseph J; Salomone, Alberto; Gerace, Enrico; Di Corcia, Daniele; Vincenti, Marco; Cleland, Charles M
2017-10-01
Data on both known and unknown drug use in the electronic dance music (EDM) scene is important to inform prevention and harm reduction. While surveys are the most common method of querying drug use, additional biological data can help validate use and detect unknown/unintentional use of drugs such as new psychoactive substances (NPS). We sought to determine the extent of both known and unknown use of various substances in this high-risk scene. We hair-tested 90 self-reported past-year ecstasy/MDMA/Molly users attending EDM parties in New York City during the summer of 2016 using UHPLC-MS/MS. Results were compared to self-reported past-year use. Three quarters (74.4%) tested positive for MDMA, a third (33.3%) tested positive for an NPS, and 27.8% tested positive specifically for one or more synthetic cathinones (e.g., butylone, ethylone, pentylone, methylone, alpha-PVP). Half (51.1%) of participants tested positive for a drug not self-reported, with most testing positive for synthetic cathinones (72.0%), methamphetamine (69.0%), other NPS stimulants (e.g., 4-FA, 5/6-APB; 66.7%), or new dissociatives (e.g., methoxetamine, diphenidine; 60.0%). Attending parties every other week or more often, reporting higher-frequency ecstasy pill use, having tested one's ecstasy, and having found out one's ecstasy was adulterated, were risk factors for testing positive for synthetic cathinones and NPS in general. Hair testing appears to be a valuable addition to drug epidemiology studies. Many EDM party attendees-even those who test their ecstasy-are unknowingly using NPS and/or other drugs. Prevention information and harm reduction may help reduce unknown/unintentional use. Copyright © 2017 Elsevier B.V. All rights reserved.
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Uribe-Beltrán, Magdalena de Jesús; Ahumada-Santos, Yesmi Patricia; Díaz-Camacho, Sylvia Páz; Eslava-Campos, Carlos Alberto; Reyes-Valenzuela, Jesús Ernesto; Báez-Flores, María Elena; Osuna-Ramírez, Ignacio; Delgado-Vargas, Francisco
2017-07-01
This paper aims to evaluate the antimicrobial resistance of Esherichia coli isolates from children under 5 years old, with and without diarrhoea, who were hospital outpatients in Culiacan, Sinaloa, Mexico. It also looks at the antimicrobial activity of fruit extracts against selected multidrug-resistant (MDR) E. coli strains. A total of 205 E. coli isolates from stool samples were collected from 94 children under 5 years old who were outpatients from two hospitals in the city of Culiacan, Sinaloa, Mexico, during the autumn/winter of 2003/04; their resistance profiles to 19 commercial antimicrobials were investigated using the Kirby-Bauer method. The antibacterial activities of extracts/fractions of fruits (i.e. uvalama, Vitex mollis; ayale, Crescentia alata; and arrayan, Psidium sartorianum) were evaluated using the broth microdilution method. All E. coli isolates were susceptible to amikacin, nitrofurantoin and meropenem, and approximately 96 % were resistant to at least one antimicrobial, especially carbenicillin (93.2 %), cefuroxime sodium (53.7 %), ampicillin (40 %) and trimethoprim/sulfamethoxazole (35.1 %). Likewise, the frequency of MDR strains (44.9 %) was high, and no significant association with diarrhoea symptoms was found. Remarkably, all fruit extracts/fractions showed antibacterial activity against some, but not all, MDR isolates. The lowest minimal inhibitory concentration values were for the hexane fraction of arrayan (0.25 mg ml-1). A high number of antimicrobial-resistant E. coli (especially to β-lactams and sulfonamides) and MDR isolates were detected in children under 5 years old, irrespective of diarrhoea symptoms; this is novel information for Culiacan, Sinaloa, Mexico. Moreover, our results showed that the studied fruit extracts/fractions are potential alternative or complementary treatments for MDR E. coli strains.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kruckeberg, A.L.; Wu, L.
1992-06-01
Herbaceous plant species colonizing four copper mine waste sites in northern California were investigated for copper tolerance and copper accumulation. Copper tolerance was found in plant species colonizing soils with high concentrations of soil copper. Seven of the eight plant species tested were found at more than one copper mine. The mines are geographically isolated, which makes dispersal of seeds from one mine to another unlikely. Tolerance has probably evolved independently at each site. The nontolerant field control population of Vulpia microstachya displays significantly higher tolerance to copper at all copper concentration levels tested than the nontolerant Vulpia myrous population,more » and the degree of copper tolerance attained by V. microstachya at the two copper mines was much greater than that found in V. myrous. It suggests that even in these two closely related species, the innate tolerance in their nontolerant populations may reflect their potential for evolution of copper tolerance and their ability to initially colonize copper mine waste sites. The shoot tissue of the copper mine plants of Arenaria douglasii, Bromous mollis, and V. microstachya accumulated less copper than those plants of the same species from the field control sites when the two were grown in identical conditions in nutrient solution containing copper. The root tissue of these mine plants contain more copper than the roots of the nonmine plants. This result suggests that exclusion of copper from the shoots, in part by immobilization in the roots, may be a feature of copper tolerance. No difference in the tissue copper concentration was detected between tolerant and nontolerant plants of Lotus purshianus, Lupinus bicolor, and Trifolium pratense even though the root tissue had more copper than the leaves.« less
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Molander, Marianne; Nielsen, Line; Søgaard, Søren; Staerk, Dan; Rønsted, Nina; Diallo, Drissa; Chifundera, Kusamba Zacharie; van Staden, Johannes; Jäger, Anna K
2014-11-18
Snakebite envenomation, every year, causes estimated 5-10,000 mortalities and results in more than 5-15,000 amputations in sub-Saharan Africa alone. Antiserum is not easily accessible in these regions or doctors are simply not available, thus more than 80% of all patients seek traditional practitioners as first-choice. Therefore it is important to investigate whether the plants used in traditional medicine systems contain compounds against the necrosis-inducing enzymes of snake venom. Extracts from traditionally used plants from DR Congo, Mali and South Africa were tested in hyaluronidase, phospholipase A2 and protease enzyme bioassays using Bitis arietans and Naja nigricollis as enzyme source. A total of 226 extracts from 94 different plant species from the three countries, Mali, Democratic Republic of Congo and South Africa were tested in phospholipase A2, proteases and hyaluronidase enzyme assays. Forty plant species showed more than 90% inhibition in one or more assay. Fabaceae, Anacardiaceae and Malvaceae were the families with the highest number of active species, and the active compounds were distributed in different plant parts depending on plant species. Polyphenols were removed in the search for specific enzyme inhibitors against hyaluronidase, phospholipase A2 or proteases from extracts with IC50 values below 100µg/ml. Water extracts of Pupalia lappacea, Combretum molle, Strychnos innocua and Grewia mollis and ethanol extract of Lannea acida and Bauhinia thonningii still showed IC50 values below 100µg/ml in either the hyaluronidase or protease bioassay after removal of polyphenols. As four of the active plants are widely distributed in the areas where the snake species Bitis arietans and Naja nigricollis occur a potential inhibitor of the necrotic enzymes is accessible for many people in sub-Saharan Africa. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
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The bear in Eurasian plant names: motivations and models.
Kolosova, Valeria; Svanberg, Ingvar; Kalle, Raivo; Strecker, Lisa; Özkan, Ayşe Mine Gençler; Pieroni, Andrea; Cianfaglione, Kevin; Molnár, Zsolt; Papp, Nora; Łuczaj, Łukasz; Dimitrova, Dessislava; Šeškauskaitė, Daiva; Roper, Jonathan; Hajdari, Avni; Sõukand, Renata
2017-02-21
Ethnolinguistic studies are important for understanding an ethnic group's ideas on the world, expressed in its language. Comparing corresponding aspects of such knowledge might help clarify problems of origin for certain concepts and words, e.g. whether they form common heritage, have an independent origin, are borrowings, or calques. The current study was conducted on the material in Slavonic, Baltic, Germanic, Romance, Finno-Ugrian, Turkic and Albanian languages. The bear was chosen as being a large, dangerous animal, important in traditional culture, whose name is widely reflected in folk plant names. The phytonyms for comparison were mostly obtained from dictionaries and other publications, and supplemented with data from databases, the co-authors' field data, and archival sources (dialect and folklore materials). More than 1200 phytonym use records (combinations of a local name and a meaning) for 364 plant and fungal taxa were recorded to help find out the reasoning behind bear-nomination in various languages, as well as differences and similarities between the patterns among them. Among the most common taxa with bear-related phytonyms were Arctostaphylos uva-ursi (L.) Spreng., Heracleum sphondylium L., Acanthus mollis L., and Allium ursinum L., with Latin loan translation contributing a high proportion of the phytonyms. Some plants have many and various bear-related phytonyms, while others have only one or two bear names. Features like form and/or surface generated the richest pool of names, while such features as colour seemed to provoke rather few associations with bears. The unevenness of bear phytonyms in the chosen languages was not related to the size of the language nor the present occurence of the Brown Bear in the region. However, this may, at least to certain extent, be related to the amount of the historical ethnolinguistic research done on the selected languages.
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Emergency Department Patient Burden from an Electronic Dance Music Festival.
Chhabra, Neeraj; Gimbar, Renee P; Walla, Lisa M; Thompson, Trevonne M
2018-04-01
Electronic dance music (EDM) festivals are increasingly common and psychoactive substance use is prevalent. Although prehospital care can obviate the transfer of many attendees to health care facilities (HCFs), little is known regarding the emergency department (ED) burden of patients presenting from EDM festivals. This study describes the patient volume, length of stay (LOS), and presenting complaints of patients from a 3-day EDM festival in close proximity to an area ED. Medical charts of patients presenting to one HCF from an EDM festival were reviewed for substances used, ED LOS, and sedative medications administered. Additionally, preparedness techniques are described. Over the 3-day festival, 28 patients presented to the ED (median age 21 years; range 18-29 years). Twenty-five had complaints related to substance use including ethanol (n = 18), "molly" or "ecstasy" (n = 13), and marijuana (n = 8). Three patients required intensive care or step-down unit admission for endotracheal intubation, rhabdomyolysis, and protracted altered mental status. The median LOS for discharged patients was 265 min (interquartile range 210-347 min). Eleven patients required the use of sedative medications, with cumulative doses of 42 mg of lorazepam and 350 mg of ketamine. All patients presented within the hours of 5:00 pm and 2:15 am. The majority of ED visits from an EDM festival were related to substance use. ED arrival times clustered during the evening and were associated with prolonged LOS. Few patients required hospital admission, but admitted patients required high levels of care. HCFs should use these data as a guide in planning for future events. Copyright © 2017 Elsevier Inc. All rights reserved.
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Using Local Stories as a Call to Action on Climate Change Adaptation and Mitigation in Minnesota
NASA Astrophysics Data System (ADS)
Phipps, M.
2015-12-01
Climate Generation: A Will Steger Legacy and the University of Minnesota's Regional Sustainability Development Partnerships (RSDP) have developed a novel approach to engaging rural Minnesotans on climate change issues. Through the use of personal, local stories about individuals' paths to action to mitigate and or adapt to climate change, Climate Generation and RSDP aim to spur others to action. Minnesota's Changing Climate project includes 12 Climate Convenings throughout rural Minnesota in a range of communities (tourism-based, agrarian, natural resources-based, university towns) to engage local populations in highly local conversations about climate change, its local impacts, and local solutions currently occurring. Climate Generation and RSDP have partnered with Molly Phipps Consulting to evaluate the efficacy of this approach in rural Minnesota. Data include pre and post convening surveys examining participants' current action around climate change, attitudes toward climate change (using questions from Maibach, Roser-Renouf, and Leiserowitz, 2009), and the strength of their social network to support their current and ongoing work toward mitigating and adapting to climate change. Although the Climate Convenings are tailored to each community, all include a resource fair of local organizations already engaging in climate change mitigation and adaptation activities which participants can participate in, a welcome from a trusted local official, a presentation on the science of climate change, sharing of local climate stories, and break-out groups where participants can learn how to get involved in a particular mitigation or adaptation strategy. Preliminary results have been positive: participants feel motivated to work toward mitigating and adapting to climate change, and more local stories have emerged that can be shared in follow-up webinars and on a project website to continue to inspire others to act.
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Gorain, Prakash Chandra; Sengupta, Sarban; Satpati, Gour Gopal; Paul, Ishita; Tripathi, Sudipta; Pal, Ruma
2018-06-01
Large influx of excess nutrients into sub-tropical brackish-water habitats is expected to radically affect the algal populations in the heavily populated Sunderbans brackish-water ecozone. Twelve selected brackish-water sites in the Indian Sunderbans were surveyed to investigate the growth performance of mat-forming dominant algal/cyanobacterial macrophytes and their potential for carbon (C) sequestration into hydrologic and pedologic pools. The mats were dominated by particular taxa at different seasons related to physico-chemical properties of the wetland habitats. Different environmental variables and biomass productivity parameters were measured on fortnightly basis to assess the carbon cycle related to dominant algal blooms of the study area. The dominating species at the twelve sites included seven genera (Spirogyra, Rhizoclonium, Ulva, Cladophora, Pithophora, Chaetomorpha) belonging to Chlorophyta, three genera (Polysiphonia, Gracilaria, Catenella) belonging to Rhodophyta and Lyngbya majuscula from cyanobacteria. Multivariate statistical methods indicated that nutrient availability, particularly dissolved P concentration and N:P ratio in the water column, along with salinity in the water column mainly affected biomass yield and C sequestration of mat-forming macrophytes and OC input into water column. However, OC contents of underlying muck proved to be very stable, though small influxes of OC occurred at each bloom. High biomass yields (34-3107 g/m 2 ) of the dominant mat components accumulated enormous stocks of OC, very little of which reaches the pedologic pool. This transient biomass might be utilized as dietary supplements or biofuel feedstocks. Availability of important dietary fatty acids in Spirogyra punctulata, Gracilaria sp., Polysiphonia mollis, Rhizoclonium riparium, R. tortuosum, Pithophora oedogonia and Ulva lactuca was considered as suitability of these species as nutraceuticals. Fatty acid compositions of L. majuscula, Catenella repens, R
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Self-reported use of novel psychoactive substances among attendees of electronic dance music venues
Palamar, Joseph J.; Acosta, Patricia; Sherman, Scott; Ompad, Danielle C.; Cleland, Charles M.
2016-01-01
Background Novel psychoactive substances (NPSs) continue to emerge in the United States and worldwide. Few epidemiological studies have examined the prevalence and correlates of use. Objective We examined the extent of NPS use in a high-risk population—attendees of electronic dance music (EDM) parties at nightclubs and festivals. Methods We surveyed 682 adults (age 18–25) entering EDM events at nightclubs and festivals in New York City (NYC) in 2015. A variation of time–space sampling was used. We examined the prevalence of self-reported use of 196 NPS and correlates of any NPS use. Results Over a third (35.1%) of participants reported lifetime use of any NPS. Self-reported use of synthetic cannabinoids was most prevalent (16.3%), followed by psychedelic phenethylamines (14.7%; 2C series: 10.3%, 2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine [NBOMe] series: 9.0%, Dox series: 3.5%), synthetic cathinones (“bath salts”, 6.9%), other psychedelics (6.6%), tryptamines (5.1%), and dissociatives (4.3%). 2C-I was the most prevalent 2C series drug (5.1%); methylone was the most prevalent synthetic cathinone (3.3%), 2-MeO-ketamine was the most prevalent dissociative (3.7%), and 1P-lysergic acid diethylamide (LSD) (2.9%) was the most prevalent non-phenethylamine psychedelic. Risk factors for NPS use included Ecstasy/MDMA/ Molly, LSD, and ketamine use; identifying as bisexual (compared to heterosexual), reporting higher frequency of nightclub/festival attendance, and being surveyed outside of a festival (compared to those surveyed outside of nightclubs). Discussion NPS use is prevalent in the nightclub and festival scenes in NYC. Since individuals in these scenes—especially frequent attendees—are at high risk for use, prevention and harm reduction services need to be geared toward this population. PMID:27315522
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Kauhl, Boris; Maier, Werner; Schweikart, Jürgen; Keste, Andrea; Moskwyn, Marita
2018-01-01
Chronic obstructive pulmonary disease (COPD) has a high prevalence rate in Germany and a further increase is expected within the next years. Although risk factors on an individual level are widely understood, only little is known about the spatial heterogeneity and population-based risk factors of COPD. Background knowledge about broader, population-based processes could help to plan the future provision of healthcare and prevention strategies more aligned to the expected demand. The aim of this study is to analyze how the prevalence of COPD varies across northeastern Germany on the smallest spatial-scale possible and to identify the location-specific population-based risk factors using health insurance claims of the AOK Nordost. To visualize the spatial distribution of COPD prevalence at the level of municipalities and urban districts, we used the conditional autoregressive Besag-York-Mollié (BYM) model. Geographically weighted regression modelling (GWR) was applied to analyze the location-specific ecological risk factors for COPD. The sex- and age-adjusted prevalence of COPD was 6.5% in 2012 and varied widely across northeastern Germany. Population-based risk factors consist of the proportions of insurants aged 65 and older, insurants with migration background, household size and area deprivation. The results of the GWR model revealed that the population at risk for COPD varies considerably across northeastern Germany. Area deprivation has a direct and an indirect influence on the prevalence of COPD. Persons ageing in socially disadvantaged areas have a higher chance of developing COPD, even when they are not necessarily directly affected by deprivation on an individual level. This underlines the importance of considering the impact of area deprivation on health for planning of healthcare. Additionally, our results reveal that in some parts of the study area, insurants with migration background and persons living in multi-persons households are at elevated risk
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Ethnobotany, biochemistry and pharmacology of Minthostachys (Lamiaceae).
Schmidt-Lebuhn, A N
2008-08-13
The South American mint genus Minthostachys is of great importance in the Andes as a medicinal, aromatic, culinary and commercial essential oil plant. After decades of taxonomic confusion and virtual indeterminability of specimens, new systematic and taxonomic work has been conducted in recent years. The present paper attempts to summarize the state of knowledge about Minthostachys with a focus on ethnobotany, analyses of essential oil content and pharmacology, to identify the currently accepted species names for the plants examined in these previous studies, and to assess where additional research is needed. All available studies on Minthostachys were obtained and evaluated. Herbaria were contacted to identify voucher specimens cited in the respective publications. The great majority of published studies was conducted on a single species, Argentinean Minthostachys verticillata. In contrast, the most widely distributed and well-known species (Minthostachys mollis) as well as several locally important and intensively used species (e.g., Minthostachys acutifolia) have received disproportionately little attention, and virtually nothing is known about the local endemics among the 17 species currently recognized. In many cases, however, it is difficult to relate the results to taxonomic entities due to the lack of voucher specimens. Future research efforts should especially be directed at studying the chemistry and potential for use of several common but so far neglected species of the central and northern Andes, at disentangling environmental and genetic influences on essential oil composition, at prerequisites for cultivation, and at the pharmacological basis of the most important traditional uses. Because of the morphological complexity of the genus, future researchers are urged to deposit voucher specimens of the plants used in their studies to facilitate species identification and to make the results more comparable and reproducible.
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Reporting of Telehealth-Delivered Dietary Intervention Trials in Chronic Disease: Systematic Review.
Warner, Molly M; Kelly, Jaimon T; Reidlinger, Dianne P; Hoffmann, Tammy C; Campbell, Katrina L
2017-12-11
results and implementation of effective interventions in clinical practice. ©Molly M Warner, Jaimon T Kelly, Dianne P Reidlinger, Tammy C Hoffmann, Katrina L Campbell. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 11.12.2017.
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Clark, Melody S; Sommer, Ulf; Sihra, Jaspreet K; Thorne, Michael A S; Morley, Simon A; King, Michelle; Viant, Mark R; Peck, Lloyd S
2017-01-01
Understanding species' responses to environmental change underpins our abilities to make predictions on future biodiversity under any range of scenarios. In spite of the huge biodiversity in most ecosystems, a model species approach is often taken in environmental studies. To date, we still do not know how many species we need to study to input into models and inform on ecosystem-level responses to change. In this study, we tested current paradigms on factors setting thermal limits by investigating the acute warming response of six Antarctic marine invertebrates: a crustacean Paraceradocus miersi, a brachiopod Liothyrella uva, two bivalve molluscs, Laternula elliptica, Aequiyoldia eightsii, a gastropod mollusc Marseniopsis mollis and an echinoderm Cucumaria georgiana. Each species was warmed at the rate of 1 °C h -1 and taken to the same physiological end point (just prior to heat coma). Their molecular responses were evaluated using complementary metabolomics and transcriptomics approaches with the aim of discovering the underlying mechanisms of their resilience or sensitivity to warming. The responses were species-specific; only two showed accumulation of anaerobic end products and three exhibited the classical heat shock response with expression of HSP70 transcripts. These diverse cellular measures did not directly correlate with resilience to heat stress and suggested that each species may have a different critical point of failure. Thus, one unifying molecular mechanism underpinning response to warming could not be assigned, and no overarching paradigm was supported. This biodiversity in response makes future ecosystems predictions extremely challenging, as we clearly need to develop a macrophysiology-type approach to cellular evaluations of the environmental stress response, studying a range of well-rationalized members from different community levels and of different phylogenetic origins rather than extrapolating from one or two arbitrary model species.
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Populations and habitat relationships of Piute ground squirrels in southwest Idaho
Steenhof, Karen; Yensen, Eric; Kochert, Michael N.; Gage, K.
2006-01-01
Piute ground squirrels (Spermophilus mollis idahoensis) are normally above ground from late January until late June or early July in the Snake River Birds of Prey National Conservation Area in southwestern Idaho. In 2002 they were rarely seen above ground after early May. Because of the ecological importance of ground squirrels for nesting raptors and other species, we sought to determine the reasons for their early disappearance. We sampled 12 sites from January 2003 through March 2003 to determine if a population crash had occurred in 2002. Tests indicated that Piute ground squirrels had not been exposed to plague within the past year. The presence of yearlings in the population indicated that squirrels reproduced in 2002 and that at least some yearlings survived the winter. Both yearling and adult squirrels appeared to be reproducing at or above normal rates in 2003. The most plausible explanation for the early disappearance of Piute ground squirrels in 2002 is that squirrels entered seasonal torpor early in response to a late spring drought. In addition, the breeding chronology of squirrels may have shifted during the past 2 decades in response to climate change and/or habitat alteration. Shrub habitats provide a more favorable and stable environment for squirrels than grass habitats. Squirrel abundance was higher on live-trapping grids with sagebrush than on grids dominated by grass, and squirrel masses were higher at sites dominated by shrubs and Sandberg bluegrass (Poa secunda). Densities in big sagebrush (Artemisia tridentata) were within the ranges reported for earlier years, but densities in grass were lower than previously reported. Low densities at grassland sites in 2003 support other findings that drought affects squirrels in altered grass communities more than those in native shrub habitats. Long-term shifts in ground squirrel breeding chronology may have implications for raptors that depend on them for food.
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Alhdiri, Maryam Ahmed; Samat, Nor Azah; Mohamed, Zulkifley
2017-03-01
Cancer is the most rapidly spreading disease in the world, especially in developing countries, including Libya. Cancer represents a significant burden on patients, families, and their societies. This disease can be controlled if detected early. Therefore, disease mapping has recently become an important method in the fields of public health research and disease epidemiology. The correct choice of statistical model is a very important step to producing a good map of a disease. Libya was selected to perform this work and to examine its geographical variation in the incidence of lung cancer. The objective of this paper is to estimate the relative risk for lung cancer. Four statistical models to estimate the relative risk for lung cancer and population censuses of the study area for the time period 2006 to 2011 were used in this work. They are initially known as Standardized Morbidity Ratio, which is the most popular statistic, which used in the field of disease mapping, Poisson-gamma model, which is one of the earliest applications of Bayesian methodology, Besag, York and Mollie (BYM) model and Mixture model. As an initial step, this study begins by providing a review of all proposed models, which we then apply to lung cancer data in Libya. Maps, tables and graph, goodness-of-fit (GOF) were used to compare and present the preliminary results. This GOF is common in statistical modelling to compare fitted models. The main general results presented in this study show that the Poisson-gamma model, BYM model, and Mixture model can overcome the problem of the first model (SMR) when there is no observed lung cancer case in certain districts. Results show that the Mixture model is most robust and provides better relative risk estimates across a range of models. Creative Commons Attribution License
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Is Fish Response related to Velocity and Turbulence Magnitudes? (Invited)
NASA Astrophysics Data System (ADS)
Wilson, C. A.; Hockley, F. A.; Cable, J.
2013-12-01
Riverine fish are subject to heterogeneous velocities and turbulence, and may use this to their advantage by selecting regions which balance energy expenditure for station holding whilst maximising energy gain through feeding opportunities. This study investigated microhabitat selection by guppies (Poecilia reticulata) in terms of the three-dimensional velocity structure generated by idealised boulders in an experimental flume. Velocity and turbulence influenced intra-species variation in swimming behaviour with respect to size, sex and parasite intensity. With increasing body length, fish swam further and more frequently between boulder regions. Larger guppies spent more time in the high velocity and low turbulence region, whereas smaller guppies preferred the low velocity and high shear stress region directly behind the boulders. Male guppies selected the region of low velocity, indicating a possible reduced swimming ability due to hydrodynamic drag imposed by their fins. With increasing parasite (Gyrodactylus turnbulli) burden, fish preferentially selected the region of moderate velocity which had the lowest bulk measure of turbulence of all regions and was also the most spatially homogeneous velocity and turbulence region. Overall the least amount of time was spent in the recirculation zone which had the highest magnitude of shear stresses and mean vertical turbulent length scale to fish length ratio. Shear stresses were a factor of two greater than in the most frequented moderate velocity region, while mean vertical turbulent length scale to fish length ratio were six times greater. Indeed the mean longitudinal turbulent scale was 2-6 times greater than the fish length in all regions. While it is impossible to discriminate between these two turbulence parameters (shear stress and turbulent length to fish length ratio) in influencing the fish preference, our study infers that there is a bias towards fish spending more time in a region where both the bulk
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Miller, Lisa K; Brooks, Robert
2005-11-01
The traits thought to advertise genetic quality are often highly susceptible to environmental variation and prone to change with age. These factors may either undermine or reinforce the potential for advertisement traits to signal quality depending on the magnitude of age-dependent expression, environmental variation, and genotype-age and genotype-environment interaction. Measurements of the magnitude of these effects are thus a necessary step toward assessing the implications of age dependence and environmental variability for the evolution of signals of quality. We conducted a longitudinal study of male guppies (Poecilia reticulata) from 22 full-sibling families. Each fish was assigned at maturity to one of three treatments in order to manipulate his allocation of resources to reproduction: a control in which the male was kept alone, a courtship-only treatment in which he could see and court a female across a clear partition, and a mating treatment in which he interacted freely with a female. We measured each male's size, ornamental color patterns, courtship, attractiveness to females, and mating success at three ages. Size was influenced by treatment and age-treatment interactions, indicating that courtship and mating may impose costs on growth. Tail size and color patterns were influenced by age but not by treatment, suggesting fixed age-dependent trajectories in these advertisement traits. By contrast, display rate and attempted sneak copulation rate differed among treatments but not among ages, suggesting greater plasticity of these behavioral traits. As a result of the different patterns of variation in ornamentation and behavior, male attractiveness and mating success responded to male age, treatment, and the interaction between age and treatment. Neither age nor treatment obscured the presence of genetic variation, and the genetic relationship between male ornamentation and attractiveness remained the same among treatments. Our findings suggest that