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Sample records for victoria cichlid haplochromis

  1. Adaptive responses to environmental changes in Lake Victoria cichlids

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    Rijssel, Jacobus Cornelis van (Jacco)

    2014-01-01

    Lake Victoria cichlids show the fastest vertebrate adaptive radiation known which is why they function as a model organism to study evolution. In the past 40 years, Lake Victoria experienced severe environmental changes including the boom of the introduced, predatory Nile perch and eutrophication.

  2. Climatic variability in combination with eutrophication drives adaptive responses in the gills of Lake Victoria cichlids.

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    van Rijssel, Jacco C; Hecky, Robert E; Kishe-Machumu, Mary A; Meijer, Saskia E; Pols, Johan; van Tienderen, Kaj M; Ververs, Jan D; Wanink, Jan H; Witte, Frans

    2016-12-01

    Textbook examples of adaptive radiation often show rapid morphological changes in response to environmental perturbations. East Africa's Lake Victoria, famous for its stunning adaptive radiation of cichlids, has suffered from human-induced eutrophication over the past decades. This cultural eutrophication is thought to be partly responsible for the dramatically reduced cichlid biodiversity, but climatic variability in itself might also have contributed to the eutrophication which resulted in low oxygen levels and decreased water transparency. To determine how recent environmental changes have influenced the lake and its cichlids over the past 50 years, we gathered environmental and meteorological variables and compared these with gill surface area of four cichlid species. We found that during the period of severe eutrophication and temperature increase (1980s), reduced wind speeds coincided with a reduction in oxygen levels and a decrease in both water temperature and transparency. The gill surface area in three out of the four cichlid species increased during this period which is consistent with adaptive change in response to increased hypoxia. During the 2000s, wind speeds, oxygen levels, water transparency and water temperature increased again, while cichlid gill surface area decreased. Our results imply that climatic changes and especially wind speed and direction might play a crucial role in tropical lake dynamics. The changes in Lake Victoria's water quality coincide with fluctuations in cichlid gill surface area, suggesting that these fish can respond rapidly to environmental perturbations, but also that climatic variability, together with continued eutrophication, might be detrimental to the lake's cichlid biodiversity.

  3. Parasite-mediated sexual selection and species divergence in Lake Victoria cichlid fish

    NARCIS (Netherlands)

    Maan, Martine E.; Van Rooijen, Anne M. C.; Van Alphen, Jacques J. M.; Seehausen, Ole

    We investigate the role of parasite-mediated sexual selection in the divergence of two species of Lake Victoria cichlids. Pundamilia pundamilia and Pundamilia nyererei represent a common pattern of male nuptial colour divergence between haplochromine sister species: metallic grey-blue in P.

  4. Species-specific relationships between water transparency and male coloration within and between two closely related Lake Victoria cichlid species

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    Castillo Cajas, Ruth F; Selz, Oliver M; Ripmeester, Erwin A P; Seehausen, Ole; Maan, Martine E

    2012-01-01

    Environmental variation in signalling conditions affects animal communication traits, with possible consequences for sexual selection and reproductive isolation. Using spectrophotometry, we studied how male coloration within and between populations of two closely related Lake Victoria cichlid

  5. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

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    Kohta Yoshida

    2011-08-01

    Full Text Available The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85% in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

  6. B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

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    Yoshida, Kohta; Terai, Yohey; Mizoiri, Shinji; Aibara, Mitsuto; Nishihara, Hidenori; Watanabe, Masakatsu; Kuroiwa, Asato; Hirai, Hirohisa; Hirai, Yuriko; Matsuda, Yoichi; Okada, Norihiro

    2011-08-01

    The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85%) in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb) revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

  7. Biological Diversity and Resilience: Lessons from the Recovery of Cichlid Species in Lake Victoria

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    Alex O. Awiti

    2011-03-01

    Full Text Available A fundamental feature of the Anthropocene is the inexorable erosion of the self-repairing capacity or adaptive renewal of natural systems because of natural perturbation, exploitation, or management failure. The concept of resilience offers a systematic framework for understanding the dynamics and variables that govern response dynamics of ecosystems. Resilience of haplochromine cichlids is assessed using limnological and biodiversity changes in Lake Victoria, the world's second largest freshwater lake, over the last five decades. The review explores the resurgence of the haplochromine cichlids using Holling's adaptive renewal cycle and attempts to illustrate how resilience-based management approaches might learn from an inadvertent management experiment. The introduction in the 1980s of the Nile perch (Lates niloticus, a fecund and voracious predator of the endemic phytoplankton feeding haplochromine cichlids, anthropogenic eutrophication, and deep water hypoxia have combined in a synergistic way to increase the vulnerability of the lake ecosystem to perturbations that were hitherto absorbed. However, the upsurge in commercial Nile perch fishing appears to be enabling the resurgence of the haplochromine cichlids. The resurgence of haplochromine cichlids is characterized by phenotypic plasticity, ecological and life history traits and demonstrates the critical role of response diversity in the maintenance of systems resilience. Resilience of the haplochromine cichlids resides in the requisite functional response diversity and habitat diversity that provide the resources for renewal and regeneration. This paper concludes that management of Nile perch fisheries and control of nutrient loading into Lake Victoria could halt or reverse eutrophication, hence offer the best promise for a diverse, productive, and resilient social-ecological system.

  8. Genetic structure of pelagic and littoral cichlid fishes from Lake Victoria.

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    Miyuki Takeda

    Full Text Available The approximately 700 species of cichlids found in Lake Victoria in East Africa are thought to have evolved over a short period of time, and they represent one of the largest known examples of adaptive radiation. To understand the processes that are driving this spectacular radiation, we must determine the present genetic structure of these species and elucidate how this structure relates to the ecological conditions that caused their adaptation. We analyzed the genetic structure of two pelagic and seven littoral species sampled from the southeast area of Lake Victoria using sequences from the mtDNA control region and 12 microsatellite loci as markers. Using a Bayesian model-based clustering method to analyze the microsatellite data, we separated these nine species into four groups: one group composed of pelagic species and another three groups composed mainly of rocky-shore species. Furthermore, we found significant levels of genetic variation between species within each group at both marker loci using analysis of molecular variance (AMOVA, although the nine species often shared mtDNA haplotypes. We also found significant levels of genetic variation between populations within species. These results suggest that initial groupings, some of which appear to have been related to habitat differences, as well as divergence between species within groups took place among the cichlid species of Lake Victoria.

  9. Inter-guild differences and possible causes of the recovery of cichlid species in Lake Victoria, Tanzania

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    Kishe-Machumu, Mary Alphonce

    2012-01-01

    Until the 1970s, the fish fauna of Lake Victoria was dominated by 500+ endemic haplochromine cichlid species in which detritivores was the dominant group followed by zooplanktivores. With the upsurge of Nile perch in the 1980s, a strong decline of haplochromines occurred. During the1990s, a

  10. Community genetics reveal elevated levels of sympatric gene flow among morphologically similar but not among morphologically dissimilar species of Lake Victoria cichlid fish

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    Konijnendijk, N.; Joyce, D.A.; Mrosso, H.D.J.; Egas, M.; Seehausen, O.

    2011-01-01

    We examined genetic structure among five species of Lake Victoria haplochromine cichlids in four island communities, using a full factorial sampling design that compared genetic differentiation between pairs of species and populations of varying morphological similarity and geographical proximity.

  11. Developmental effects of visual environment on species-assortative mating preferences in Lake Victoria cichlid fish.

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    Wright, D S; Demandt, N; Alkema, J T; Seehausen, O; Groothuis, T G G; Maan, M E

    2017-02-01

    Local adaptation can be a potent force in speciation, with environmental heterogeneity leading to niche specialization and population divergence. However, local adaption often requires nonrandom mating to generate reproductive isolation. Population divergence in sensory properties can be particularly consequential in speciation, affecting both ecological adaptation and sexual communication. Pundamilia pundamila and Pundamilia nyererei are two closely related African cichlid species that differ in male coloration, blue vs. red. They co-occur at rocky islands in southern Lake Victoria, but inhabit different depth ranges with different light environments. The species differ in colour vision properties, and females exert species-specific preferences for blue vs. red males. Here, we investigated the mechanistic link between colour vision and preference, which could provide a rapid route to reproductive isolation. We tested the behavioural components of this link by experimentally manipulating colour perception - we raised both species and their hybrids under light conditions mimicking shallow and deep habitats - and tested female preference for blue and red males under both conditions. We found that rearing light significantly affected female preference: shallow-reared females responded more strongly to P. pundamilia males and deep-reared females favoured P. nyererei males - implying that visual development causally affects mate choice. These results are consistent with sensory drive predictions, suggesting that the visual environment is key to behavioural isolation of these species. However, the observed plasticity could also make the species barrier vulnerable to environmental change: species-assortative preferences were weaker in females that were reared in the other species' light condition. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  12. Developmental effects of environmental light on male nuptial coloration in Lake Victoria cichlid fish

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    Daniel Shane Wright

    2018-01-01

    Full Text Available Background Efficient communication requires that signals are well transmitted and perceived in a given environment. Natural selection therefore drives the evolution of different signals in different environments. In addition, environmental heterogeneity at small spatial or temporal scales may favour phenotypic plasticity in signaling traits, as plasticity may allow rapid adjustment of signal expression to optimize transmission. In this study, we explore signal plasticity in the nuptial coloration of Lake Victoria cichlids, Pundamilia pundamilia and Pundamilia nyererei. These two species differ in male coloration, which mediates species-assortative mating. They occur in adjacent depth ranges with different light environments. Given the close proximity of their habitats, overlapping at some locations, plasticity in male coloration could contribute to male reproductive success but interfere with reproductive isolation. Methods We reared P. pundamilia, P. nyererei, and their hybrids under light conditions mimicking the two depth ranges in Lake Victoria. From photographs, we quantified the nuptial coloration of males, spanning the entire visible spectrum. In experiment 1, we examined developmental colour plasticity by comparing sibling males reared in each light condition. In experiment 2, we assessed colour plasticity in adulthood, by switching adult males between conditions and tracking coloration for 100 days. Results We found that nuptial colour in Pundamilia did respond plastically to our light manipulations, but only in a limited hue range. Fish that were reared in light conditions mimicking the deeper habitat were significantly greener than those in conditions mimicking shallow waters. The species-specific nuptial colours (blue and red did not change. When moved to the opposing light condition as adults, males did not change colour. Discussion Our results show that species-specific nuptial colours, which are subject to strong divergent

  13. Heritability and heterochrony of polychromatism in a Lake Victoria cichlid fish : Stepping stones for speciation?

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    Maan, ME; Haesler, MP; Seehausen, O; Van Alphen, JJM

    2006-01-01

    In many haplochromine cichlid fish, male nuptial coloration is subject to female mate choice and plays a central role in the evolution of reproductive isolation between incipient species. Intraspecific variation in male coloration may serve as a target for diversifying sexual selection and provide a

  14. Territory quality affects female preference in a Lake Victoria cichlid fish

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    Dijkstra, Peter; van der Zee, Elsbeth; Groothuis, Ton G.G.

    Mate preferences on male colour have been implicated in generating and maintaining species diversity among haplochromine cichlid fish. Their lek-like mating system suggests that not only male colour but also territory quality is instrumental inmate choice. We assessed the relative importance of

  15. Fitness correlates of male coloration in a Lake Victoria cichlid fish

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    Maan, Martine E.; van der Spoel, Michael; Jimenez, Paloma Quesada; van Alphen, Jacques J. M.; Seehausen, Ole

    2006-01-01

    Sexual selection by female choice has contributed to the rapid evolution of phenotypic diversity in the cichlid fish species flocks of East Africa. Yet, very little is known about the ecological mechanisms that drive the evolution of female mating preferences. We studied fitness correlates of male

  16. Species-Specific Relationships between Water Transparency and Male Coloration within and between Two Closely Related Lake Victoria Cichlid Species

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    Ruth F. Castillo Cajas

    2012-01-01

    Full Text Available Environmental variation in signalling conditions affects animal communication traits, with possible consequences for sexual selection and reproductive isolation. Using spectrophotometry, we studied how male coloration within and between populations of two closely related Lake Victoria cichlid species (Pundamilia pundamilia and P. nyererei covaries with water transparency. Focusing on coloration patches implicated in sexual selection, we predicted that in clear waters, with broad-spectrum light, (1 colours should become more saturated and (2 shift in hue away from the dominant ambient wavelengths, compared to more turbid waters. We found support for these predictions for the red and yellow coloration of P. nyererei but not the blue coloration of P. pundamilia. This may be explained by the species difference in depth distribution, which generates a steeper gradient in visual conditions for P. nyererei compared to P. pundamilia. Alternatively, the importance of male coloration in intraspecific sexual selection may differ between the species. We also found that anal fin spots, that is, the orange spots on male haplochromine anal fins that presumably mimic eggs, covaried with water transparency in a similar way for both species. This is in contrast to the other body regions studied and suggests that, while indeed functioning as signals, these spots may not play a role in species differentiation.

  17. Visual adaptation in Lake Victoria cichlid fishes: depth-related variation of color and scotopic opsins in species from sand/mud bottoms.

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    Terai, Yohey; Miyagi, Ryutaro; Aibara, Mitsuto; Mizoiri, Shinji; Imai, Hiroo; Okitsu, Takashi; Wada, Akimori; Takahashi-Kariyazono, Shiho; Sato, Akie; Tichy, Herbert; Mrosso, Hillary D J; Mzighani, Semvua I; Okada, Norihiro

    2017-08-22

    For Lake Victoria cichlid species inhabiting rocky substrates with differing light regimes, it has been proposed that adaptation of the long-wavelength-sensitive (LWS) opsin gene triggered speciation by sensory drive through color signal divergence. The extensive and continuous sand/mud substrates are also species-rich, and a correlation between male nuptial coloration and the absorption of LWS pigments has been reported. However, the factors driving genetic and functional diversity of LWS pigments in sand/mud habitats are still unresolved. To address this issue, nucleotide sequences of eight opsin genes were compared in ten Lake Victoria cichlid species collected from sand/mud bottoms. Among eight opsins, the LWS and rod-opsin (RH1) alleles were diversified and one particular allele was dominant or fixed in each species. Natural selection has acted on and fixed LWS alleles in each species. The functions of LWS and RH1 alleles were measured by absorption of reconstituted A1- and A2-derived visual pigments. The absorption of pigments from RH1 alleles most common in deep water were largely shifted toward red, whereas those of LWS alleles were largely shifted toward blue in both A1 and A2 pigments. In both RH1 and LWS pigments, A2-derived pigments were closer to the dominant light in deep water, suggesting the possibility of the adaptation of A2-derived pigments to depth-dependent light regimes. The RH1 and LWS sequences may be diversified for adaptation of A2-derived pigments to different light environments in sand/mud substrates. Diversification of the LWS alleles may have originally taken place in riverine environments, with a new mutation occurring subsequently in Lake Victoria.

  18. Early learning and speciation : the effects of early experience on sexual and aggressive behaviour in Lake Victoria cichlid fish

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    Verzijden, Machteld Nicolette

    2008-01-01

    The great Lakes of East Africa are inhabited by a great number of haplochromine cichlid species, which form a diverse group in both ecology and nuptial coloration. The large number of sympatrically occuriring closely related species has raised questions about the underlying mechanism for

  19. Community Genetics Reveal Elevated Levels of Sympatric Gene Flow among Morphologically Similar but Not among Morphologically Dissimilar Species of Lake Victoria Cichlid Fish

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    N. Konijnendijk

    2011-01-01

    Full Text Available We examined genetic structure among five species of Lake Victoria haplochromine cichlids in four island communities, using a full factorial sampling design that compared genetic differentiation between pairs of species and populations of varying morphological similarity and geographical proximity. We found that allopatric conspecific populations were on average significantly more strongly differentiated than sympatric heterospecific populations of morphologically similar species. Allopatric heterospecific populations of morphologically dissimilar species were most differentiated. Our work demonstrates that phenotypic divergence can be maintained and perhaps even evolve in sympatry despite considerable gene flow between species. Conversely, phenotypic resemblance among conspecific populations can be maintained despite geographical isolation. Additionally we show that anthropogenically increased hybridization does not affect all sympatric species evenly but predominantly affects morphologically similar and closely related species. This has important implications for the evolution of reproductive isolation between species These findings are also consistent with the hypothesis of speciation reversal due to weakening of divergent selection and reproductive isolation as a consequence of habitat homogenization and offers an evolutionary mechanistic explanation for the observation that species poor assemblages in turbid areas of the lake are characterized by just one or two species in each of a few morphologically distinct genera.

  20. No evidence for a genetic association between female mating preference and male secondary sexual trait in a Lake Victoria cichlid fish

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    Inke van der SLUIJS, Ole SEEHAUSEN, Tom J. M. Van DOOREN,Jacques J. M. van ALPHEN

    2010-02-01

    Full Text Available Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 (1: 57–64 2010].

  1. Age of cichlids: new dates for ancient lake fish radiations.

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    Genner, Martin J; Seehausen, Ole; Lunt, David H; Joyce, Domino A; Shaw, Paul W; Carvalho, Gary R; Turner, George F

    2007-05-01

    Timing divergence events allow us to infer the conditions under which biodiversity has evolved and gain important insights into the mechanisms driving evolution. Cichlid fishes are a model system for studying speciation and adaptive radiation, yet, we have lacked reliable timescales for their evolution. Phylogenetic reconstructions are consistent with cichlid origins prior to Gondwanan landmass fragmentation 121-165 MYA, considerably earlier than the first known fossil cichlids (Eocene). We examined the timing of cichlid evolution using a relaxed molecular clock calibrated with geological estimates for the ages of 1) Gondwanan fragmentation and 2) cichlid fossils. Timescales of cichlid evolution derived from fossil-dated phylogenies of other bony fishes most closely matched those suggested by Gondwanan breakup calibrations, suggesting the Eocene origins and marine dispersal implied by the cichlid fossil record may be due to its incompleteness. Using Gondwanan calibrations, we found accumulation of genetic diversity within the radiating lineages of the African Lakes Malawi, Victoria and Barombi Mbo, and Palaeolake Makgadikgadi began around or after the time of lake basin formation. These calibrations also suggest Lake Tanganyika was colonized independently by the major radiating cichlid tribes that then began to accumulate genetic diversity thereafter. These results contrast with the widely accepted theory that diversification into major lineages took place within the Tanganyika basin. Together, this evidence suggests that ancient lake habitats have played a key role in generating and maintaining diversity within radiating lineages and also that lakes may have captured preexisting cichlid diversity from multiple sources from which adaptive radiations have evolved.

  2. DISTRIBUTION IN NON-TRAWLABLE AREAS OF LAKE VICTORIA ...

    African Journals Online (AJOL)

    Victoria. Netherlands Journal of. Zoology 42'. 214 -232. Witte F, Goldschmidt PC and Wanink JH. 1995. Dynamics of the haplochromine cichlid fauna and other ecological changes in the. Mwanza gmlf of Lake Victoria. In: Pitcher TH and Hart PJB (eds):. Impact of species change in fiican lakes. Chapman & Hall, London, pp.

  3. Age and spread of the haplochromine cichlid fishes in Africa.

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    Koblmüller, Stephan; Schliewen, Ulrich K; Duftner, Nina; Sefc, Kristina M; Katongo, Cyprian; Sturmbauer, Christian

    2008-10-01

    The Haplochromini are by far the most species-rich cichlid fish tribe that originated along with the so-called primary radiation of the Lake Tanganyika cichlid species flock, i.e. at the same time during which the majority of the endemic Lake Tanganyika cichlid tribes emerged. Unlike the other tribes, the haplochromines are not restricted to Lake Tanganyika but distributed throughout Africa, except for the northwestern part of the continent. Haplochromine cichlids seeded the adaptive radiation of cichlid fishes in Lakes Malawi, Kivu, Victoria, Turkana, as well as in the now extinct paleo-Lake Makgadikgadi. Here we present a comprehensive phylogenetic and phylogeographic analysis of haplochromine cichlids that is based upon DNA sequences of two mitochondrial gene segments of riverine taxa covering all major African biogeographic regions where haplochromines are found. Our analysis revealed that six lineages of haplochromines originated within a short period of time, about 5.3-4.4 MYA. These haplochromine lineages show a highly complex phylogeographic pattern, probably severely influenced by climate- and/or geology-induced changes of the environment, with river capture events most likely playing an important role for species dispersal.

  4. Divergent mating preferences and nuptial coloration in sibling species of cichlid fish

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    Sluijs, Inke van der

    2008-01-01

    Mate choice by female cichlid fish from Lake Victoria plays an important role in speciation and the maintenance of species. Females are expected to select against males that are intermediate in their phenotype during the process of speciation driven by sexual selection. To test this, we hybridized

  5. Frequency-Dependent Social Dominance in a Color Polymorphic Cichlid Fish

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    Dijkstra, Peter; Lindström, Jan; Metcalfe, Neil B.; Hemelrijk, Charlotte K.; Brendel, Mischa; Seehausen, Ole; Groothuis, Ton G.G.

    2010-01-01

    A mechanism commonly suggested to explain the persistence of color polymorphisms in animals is negative frequency-dependent selection. It could result from a social dominance advantage to rare morphs. We tested for this in males of red and blue color morphs of the Lake Victoria cichlid, Pundamilia.

  6. Dealing with food and eggs in mouthbrooding cichlids: structural and functional trade-offs in fitness related traits.

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    Tim Tkint

    Full Text Available BACKGROUND: As in any vertebrate, heads of fishes are densely packed with functions. These functions often impose conflicting mechanical demands resulting in trade-offs in the species-specific phenotype. When phenotypical traits are linked to gender-specific parental behavior, we expect sexual differences in these trade-offs. This study aims to use mouthbrooding cichlids as an example to test hypotheses on evolutionary trade-offs between intricately linked traits that affect different aspects of fitness. We focused on the oral apparatus, which is not only equipped with features used to feed and breathe, but is also used for the incubation of eggs. We used this approach to study mouthbrooding as part of an integrated functional system with diverging performance requirements and to explore gender-specific selective environments within a species. METHODOLOGY/PRINCIPAL FINDINGS: Because cichlids are morphologically very diverse, we hypothesize that the implications of the added constraint of mouthbrooding will primarily depend on the dominant mode of feeding of the studied species. To test this, we compared the trade-off for two maternal mouthbrooding cichlid species: a "suction feeder" (Haplochromis piceatus and a "biter" (H. fischeri. The comparison of morphology and performance of both species revealed clear interspecific and intersex differences. Our observation that females have larger heads was interpreted as a possible consequence of the fact that in both the studied species mouthbrooding is done by females only. As hypothesized, the observed sexual dimorphism in head shape is inferred as being suboptimal for some aspects of the feeding performance in each of the studied species. Our comparison also demonstrated that the suction feeding species had smaller egg clutches and more elongated eggs. CONCLUSIONS/SIGNIFICANCE: Our findings support the hypothesis that there is a trade-off between mouthbrooding and feeding performance in the two

  7. Dealing with Food and Eggs in Mouthbrooding Cichlids: Structural and Functional Trade-Offs in Fitness Related Traits

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    tkint, Tim; Verheyen, Erik; De Kegel, Barbara; Helsen, Philippe; Adriaens, Dominique

    2012-01-01

    Background As in any vertebrate, heads of fishes are densely packed with functions. These functions often impose conflicting mechanical demands resulting in trade-offs in the species-specific phenotype. When phenotypical traits are linked to gender-specific parental behavior, we expect sexual differences in these trade-offs. This study aims to use mouthbrooding cichlids as an example to test hypotheses on evolutionary trade-offs between intricately linked traits that affect different aspects of fitness. We focused on the oral apparatus, which is not only equipped with features used to feed and breathe, but is also used for the incubation of eggs. We used this approach to study mouthbrooding as part of an integrated functional system with diverging performance requirements and to explore gender-specific selective environments within a species. Methodology/Principal Findings Because cichlids are morphologically very diverse, we hypothesize that the implications of the added constraint of mouthbrooding will primarily depend on the dominant mode of feeding of the studied species. To test this, we compared the trade-off for two maternal mouthbrooding cichlid species: a “suction feeder” (Haplochromis piceatus) and a “biter” (H. fischeri). The comparison of morphology and performance of both species revealed clear interspecific and intersex differences. Our observation that females have larger heads was interpreted as a possible consequence of the fact that in both the studied species mouthbrooding is done by females only. As hypothesized, the observed sexual dimorphism in head shape is inferred as being suboptimal for some aspects of the feeding performance in each of the studied species. Our comparison also demonstrated that the suction feeding species had smaller egg clutches and more elongated eggs. Conclusions/Significance Our findings support the hypothesis that there is a trade-off between mouthbrooding and feeding performance in the two studied

  8. Developmental basis of phenotypic integration in two Lake Malawi cichlids

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    Pierre Le Pabic

    2016-01-01

    Full Text Available Abstract Background Cichlid fishes from the Rift Lakes of East Africa have undergone the most spectacular adaptive radiations in vertebrate history. Eco-morphological adaptations in lakes Victoria, Malawi and Tanganyika have resulted in a vast array of skull shapes and sizes, yet primary axes of morphological variation are conserved in all three radiations, prominently including the size of the preorbital region of the skull. This conserved pattern suggests that development may constrain the trajectories of cichlid head morphological evolution. Results Here, we (1 present a comparative analysis of adult head morphology in two sand-dweller cichlids from Lake Malawi with preorbital size differences representative of the main axis of variation among the three lakes and (2 analyze the ontogeny of shape and size differences by focusing on known developmental modules throughout the head. We find that (1 developmental differences between the two species correlate with known developmental modules; (2 differences in embryonic cartilage development result in phenotypically integrated changes among all bones derived from a single cartilage, while differences in dermal bone development tend to influence isolated regions within a bone; and lastly (3 species-specific morphologies appear in the embryo as subtle differences, which become progressively amplified throughout ontogeny. We propose that this amplification takes place at skeletal growth zones, the locations and shapes of which are patterned during embryogenesis. Conclusions This study is the most anatomically comprehensive analysis of the developmental differences underlying cichlid skull evolution in the Rift Lakes of East Africa. The scale of our analysis reveals previously unnoticed correlations between developmental modules and patterns of phenotypic integration. We propose that the primary axes of morphological variation among East African cichlid adaptive radiations are constrained by the

  9. Algal dermatitis in cichlids.

    Science.gov (United States)

    Yanong, Roy P E; Francis-Floyd, Ruth; Curtis, Eric; Klinger, Ruth Ellen; Cichra, Mary E; Berzins, Ilze K

    2002-05-01

    Three varieties of a popular African cichlid aquarium species, Pseudotropheus zebra, from 2 tropical fish farms in east central Florida were submitted for diagnostic evaluation because of the development of multifocal green lesions. The percentage of infected fish in these populations varied from 5 to 60%. Fish were otherwise clinically normal. Microscopic examination of fresh and fixed lesions confirmed algal dermatitis, with light invasion of several internal organs in each group. A different alga was identified from each farm. Fish from farm A were infected with Chlorochytrium spp, whereas fish from farm B were infected with Scenedesmus spp. Because of the numbers of fish involved, bath treatments to remove the algae from affected fish from farm B were attempted, with different dosages of several common algaecides including copper sulfate pentahydrate, diuron, and sodium chloride. However, none of these treatments were successful, possibly because of the location of the algae under the scales and within the dermis, and also because of the sequestering effect of the granulomatous response. To our knowledge, this is the first report of algal dermatitis in ornamental cichlids, as well as the first report of Scenedesmus spp infection in any fish.

  10. The Impact of the Geologic History and Paleoclimate on the Diversification of East African Cichlids

    Directory of Open Access Journals (Sweden)

    Patrick D. Danley

    2012-01-01

    Full Text Available The cichlid fishes of the East African Great Lakes are the largest extant vertebrate radiation identified to date. These lakes and their surrounding waters support over 2,000 species of cichlid fish, many of which are descended from a single common ancestor within the past 10 Ma. The extraordinary East African cichlid diversity is intricately linked to the highly variable geologic and paleoclimatic history of this region. Greater than 10 Ma, the western arm of the East African rift system began to separate, thereby creating a series of rift basins that would come to contain several water bodies, including the extremely deep Lakes Tanganyika and Malawi. Uplifting associated with this rifting backponded many rivers and created the extremely large, but shallow Lake Victoria. Since their creation, the size, shape, and existence of these lakes have changed dramatically which has, in turn, significantly influenced the evolutionary history of the lakes' cichlids. This paper reviews the geologic history and paleoclimate of the East African Great Lakes and the impact of these forces on the region's endemic cichlid flocks.

  11. Sensory modalities in cichlid fish behavior

    OpenAIRE

    Escobar-Camacho, Daniel; Carleton, Karen L.

    2015-01-01

    Among teleosts, cichlids are a great model for studies of evolution, behavior, diversity and speciation. Studies of cichlid sensory systems have revealed diverse sensory capabilities that vary among species. Hence, sensory systems are important for understanding cichlid behavior from proximate and ultimate points of view. Cichlids primarily rely on five sensory channels: hearing, mechanosensation, taste, vision, and olfaction, to receive information from the environment and respond accordingl...

  12. Learned aggression biases in males of Lake Victoria cichlid fish

    NARCIS (Netherlands)

    Dijkstra, Peter D.; Seehausen, O.; Fraterman, R. E.; Groothuis, Ton G. G.

    Male-male competition for mating territories can exert negative frequency- dependent selection on a male secondary sexual trait, such as nuptial coloration. This can occur when males bias aggression towards owncoloured competitors, resulting in a fitness advantage for rare phenotypes, thereby

  13. Sensory drive in cichlid speciation

    NARCIS (Netherlands)

    Maan, Martine E.; Hofker, Kees D.; van Alphen, Jacques J. M.; Seehausen, Ole

    The role of selection in speciation is a central yet poorly understood problem in evolutionary biology. The rapid radiations of extremely colorful cichlid fish in African lakes have fueled the hypothesis that sexual selection can drive species divergence without geographical isolation. Here we

  14. Using Cichlids for Illustrating Mendel's Laws

    Science.gov (United States)

    Gennaro, Eugene D.; Winters, Charlotte M.

    1978-01-01

    A classroom experiment is proposed in which students can mate a banded or spotted convict cichlid with a pink convict cichlid and observe the markings of their "children" and "grandchildren" as a way of illustrating Mendel's Laws of Dominance and Segregation. (MN)

  15. Speciation through sensory drive in cichlid fish

    NARCIS (Netherlands)

    Seehausen, Ole; Terai, Yohey; Magalhaes, Isabel S.; Carleton, Karen L.; Mrosso, Hillary D. J.; Miyagi, Ryutaro; van der Sluijs, Inke; Schneider, Maria V.; Maan, Martine E.; Tachida, Hidenori; Imai, Hiroo; Okada, Norihiro

    2008-01-01

    Theoretically, divergent selection on sensory systems can cause speciation through sensory drive. However, empirical evidence is rare and incomplete. Here we demonstrate sensory drive speciation within island populations of cichlid fish. We identify the ecological and molecular basis of divergent

  16. victoria cross awards warrants concerning the victoria cross (1920)

    African Journals Online (AJOL)

    INTRODUCTION. In the military history of both the British Empire and of the Western World, the highest British military decoration, namely the Victoria Cross, has attained con- siderable renown. The Victoria Cross was introduced in terms of the Royal Warrant of 29 January,. 1856 and by 1957 a total of 1346 had been ...

  17. Can male-male competition stabilize speciation? A test in Lake Victoria haplochromine cichlid fish

    NARCIS (Netherlands)

    Dijkstra, PD; Seehausen, O; Gricar, Boye L.A.; Maan, ME; Groothuis, Ton G.G.

    It has been suggested that sympatric speciation can be driven by sexual selection on male mating traits alone. However, a fundamental problem for this process is the lack of ecological differentiation that would stabilize the coexistence of incipient species through frequency-dependent selection.

  18. Know thine enemy : Intra-sexual selection and sympatric speciation in Lake Victoria cichlid fish

    NARCIS (Netherlands)

    Dijkstra, Peter Douwe

    2006-01-01

    Speciation by sexual selection research has traditionally concentrated on mechanisms for divergence driven via female mate choice (intersexual selection). The pivotal role of competition between members of the same sex (intrasexual selection) has been largely overlooked. In this thesis, I describe a

  19. Developmental effects of visual environment on species-assortative mating preferences in Lake Victoria cichlid fish

    NARCIS (Netherlands)

    Wright, Daniel Shane; Demandt, Nicolle; Alkema, Jeroen T; Seehausen, Ole; Groothuis, Ton G G; Maan, Martine E

    Local adaptation can be a potent force in speciation, with environmental heterogeneity leading to niche specialization and population divergence. However, local adaption often requires nonrandom mating to generate reproductive isolation. Population divergence in sensory properties can be

  20. Direct male-male competition can facilitate invasion of new colour types in Lake Victoria cichlids

    NARCIS (Netherlands)

    Dijkstra, PD; Seehausen, O; Groothuis, TGG; Groothuis, Ton G.G.; St. Mary, C.

    The possibility that disruptive sexual selection alone can cause sympatric speciation is currently a subject of much debate. The initial difficulty for new and rare ornament phenotypes to invade a population, and the stabilisation of the resulting polymorphism in trait and preference make this

  1. [The epilepsy of Guadalupe Victoria].

    Science.gov (United States)

    Soto-Pérez-de-Celis, Enrique

    2008-01-01

    Guadalupe Victoria, the first President of Mexico, passed away in 1843 uictim of an ailment that, at the time, was diagnosed as epilepsy. The clinical data and the pathologic findings, however, suggest the possibility that Victoria had an underlying disease that was responsible for the seizures that affected him. In this article I propose that Guadalupe Victoria had in fact Chagas Disease, and that he was infected with this parasitic malady while he lived in the tropical jungles of Veracruz, in eastern Mexico. Even though there aren't many published works regarding seizures secondary to chronic Chagas Disease, there are good descriptions of epileptic syndromes in patients with this infection. At the same time, the cardiac findings in Victoria's autopsy support the idea that he had some kind of cardiac pathology; in this case Chagasic dilated cardiomyopathy, which ultimately led to his death.

  2. VICTORIA'S SECRET Prepares for Growth

    National Research Council Canada - National Science Library

    Jordan K Speer

    2007-01-01

      After the upcoming holiday season, Victoria's Secret will take the first steps toward launching its e-commerce business on a cross-channel on-demand platform from partner n2N Commerce, a company...

  3. Introgressive hybridization in a trophically polymorphic cichlid.

    Science.gov (United States)

    Hulsey, C Darrin; García-de-León, Francisco J

    2013-11-01

    Trophically polymorphic species could represent lineages that are rapidly diverging along an ecological axis or could phenotypically mark the collapse of species through introgressive hybridization. We investigated patterns of introgression between the trophically polymorphic cichlid fish Herichthys minckleyi and its relative H. cyanoguttatus using a combination of population genetics and species tree analyses. We first examined the distribution of mitochondrial haplotypes within the alternative H. minckleyi pharyngeal jaw morphotypes that are endemic to the small desert valley of Cuatro Ciénegas. We recovered two clusters of mitochondrial haplotypes. The first contained a number of slightly differentiated cytochrome b (cytb) haplotypes that showed some phylogeographic signal and were present in both jaw morphotypes. The other haplotype was monomorphic, highly differentiated from the other cluster, present in equal frequencies in the morphotypes, and identical to H. cyanoguttatus haplotypes found outside Cuatro Ciénegas. Then, we investigated whether H. minckleyi individuals with the H. cyanoguttatus cytb were more evolutionarily similar to H. cyanoguttatus or other H. minckleyi using a species tree analysis of 84 nuclear loci. Both H. minckleyi pharyngeal morphotypes, regardless of their cytb haplotype, were quite distinct from H. cyanoguttatus. However, hybridization could be blurring subdivision within H. minckleyi as the alternative jaw morphotypes were not genetically distinct from one another. Accounting for introgression from H. cyanoguttatus will be essential to understand the evolution of the trophically polymorphic cichlid H. minckleyi.

  4. Modularity of the Oral Jaws Is Linked to Repeated Changes in the Craniofacial Shape of African Cichlids

    Science.gov (United States)

    Parsons, Kevin J.; Cooper, W. James; Albertson, R. Craig

    2011-01-01

    The African cichlids of the East-African rift-lakes provide one of the most dramatic examples of adaptive radiation known. It has long been thought that functional decoupling of the oral and pharyngeal jaws in cichlids has facilitated their explosive evolution. Recent research has also shown that craniofacial evolution from radiations in lakes Victoria, Malawi, and Tanganyika has occurred along a shared primary axis of shape divergence, whereby the preorbital region of the skull changes in a manner that is, relatively independent from other head regions. We predicted that the preorbital region would comprise a variational module and used an extensive dataset from each lake that allowed us to test this prediction using a model selection approach. Our findings supported the presence of a preorbital module across all lakes, within each lake, and for Malawi, within sand and rock-dwelling clades. However, while a preorbital module was consistently present, notable differences were also observed among groups. Of particular interest, a negative association between patterns of variational modularity was observed between the sand and rock-dwelling clades, a patter consistent with character displacement. These findings provide the basis for further experimental research involving the determination of the developmental and genetic bases of these patterns of modularity. PMID:21716745

  5. Modularity of the Oral Jaws Is Linked to Repeated Changes in the Craniofacial Shape of African Cichlids

    Directory of Open Access Journals (Sweden)

    Kevin J. Parsons

    2011-01-01

    Full Text Available The African cichlids of the East-African rift-lakes provide one of the most dramatic examples of adaptive radiation known. It has long been thought that functional decoupling of the oral and pharyngeal jaws in cichlids has facilitated their explosive evolution. Recent research has also shown that craniofacial evolution from radiations in lakes Victoria, Malawi, and Tanganyika has occurred along a shared primary axis of shape divergence, whereby the preorbital region of the skull changes in a manner that is, relatively independent from other head regions. We predicted that the preorbital region would comprise a variational module and used an extensive dataset from each lake that allowed us to test this prediction using a model selection approach. Our findings supported the presence of a preorbital module across all lakes, within each lake, and for Malawi, within sand and rock-dwelling clades. However, while a preorbital module was consistently present, notable differences were also observed among groups. Of particular interest, a negative association between patterns of variational modularity was observed between the sand and rock-dwelling clades, a patter consistent with character displacement. These findings provide the basis for further experimental research involving the determination of the developmental and genetic bases of these patterns of modularity.

  6. Identification of Cichlid Fishes from Lake Malawi Using Computer Vision

    Science.gov (United States)

    Joo, Deokjin; Kwan, Ye-seul; Song, Jongwoo; Pinho, Catarina; Hey, Jody; Won, Yong-Jin

    2013-01-01

    Background The explosively radiating evolution of cichlid fishes of Lake Malawi has yielded an amazing number of haplochromine species estimated as many as 500 to 800 with a surprising degree of diversity not only in color and stripe pattern but also in the shape of jaw and body among them. As these morphological diversities have been a central subject of adaptive speciation and taxonomic classification, such high diversity could serve as a foundation for automation of species identification of cichlids. Methodology/Principal Finding Here we demonstrate a method for automatic classification of the Lake Malawi cichlids based on computer vision and geometric morphometrics. For this end we developed a pipeline that integrates multiple image processing tools to automatically extract informative features of color and stripe patterns from a large set of photographic images of wild cichlids. The extracted information was evaluated by statistical classifiers Support Vector Machine and Random Forests. Both classifiers performed better when body shape information was added to the feature of color and stripe. Besides the coloration and stripe pattern, body shape variables boosted the accuracy of classification by about 10%. The programs were able to classify 594 live cichlid individuals belonging to 12 different classes (species and sexes) with an average accuracy of 78%, contrasting to a mere 42% success rate by human eyes. The variables that contributed most to the accuracy were body height and the hue of the most frequent color. Conclusions Computer vision showed a notable performance in extracting information from the color and stripe patterns of Lake Malawi cichlids although the information was not enough for errorless species identification. Our results indicate that there appears an unavoidable difficulty in automatic species identification of cichlid fishes, which may arise from short divergence times and gene flow between closely related species. PMID:24204918

  7. The eyes have it: regulatory and structural changes both underlie cichlid visual pigment diversity.

    Directory of Open Access Journals (Sweden)

    Christopher M Hofmann

    2009-12-01

    Full Text Available A major goal of evolutionary biology is to unravel the molecular genetic mechanisms that underlie functional diversification and adaptation. We investigated how changes in gene regulation and coding sequence contribute to sensory diversification in two replicate radiations of cichlid fishes. In the clear waters of Lake Malawi, differential opsin expression generates diverse visual systems, with sensitivities extending from the ultraviolet to the red regions of the spectrum. These sensitivities fall into three distinct clusters and are correlated with foraging habits. In the turbid waters of Lake Victoria, visual sensitivity is constrained to longer wavelengths, and opsin expression is correlated with ambient light. In addition to regulatory changes, we found that the opsins coding for the shortest- and longest-wavelength visual pigments have elevated numbers of potentially functional substitutions. Thus, we present a model of sensory evolution in which both molecular genetic mechanisms work in concert. Changes in gene expression generate large shifts in visual pigment sensitivity across the collective opsin spectral range, but changes in coding sequence appear to fine-tune visual pigment sensitivity at the short- and long-wavelength ends of this range, where differential opsin expression can no longer extend visual pigment sensitivity.

  8. Special Issue on Lake Victoria

    African Journals Online (AJOL)

    The diversity of benthic mollusks of Lake Victoria and Lake Burigi · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. JA Mwambungu, 21-32. http://dx.doi.org/10.4314/tjs.v30i1.18384 ...

  9. Mating and Parental Care in Lake Tanganyika's Cichlids

    Directory of Open Access Journals (Sweden)

    Kristina M. Sefc

    2011-01-01

    Full Text Available Cichlid fishes of Lake Tanganyika display a variety of mating and parental care behaviors, including polygamous and monogamous mouthbrooding and substrate breeding, cooperative breeding, as well as various alternative reproductive tactics such as sneaking and piracy. Moreover, reproductive behaviors sometimes vary within species both in space and in time. Here, I survey reports on mating and parenting behaviors of Lake Tanganyika cichlid species and address the evolution of mating and parental care patterns and sexual dimorphism. Notes on measures of sexual selection intensity and the difficulties of defining mating systems and estimating selection intensities at species level conclude the essay.

  10. The Victoria Project, Sri Lanka. Hydrological analysis for Victoria Dam

    Energy Technology Data Exchange (ETDEWEB)

    Piper, B.S. [GU Projects (United Kingdom); Sutcliffe, J.V. [Gibb (Sir Alexander) and Partners (United Kingdom); Parks, Y.P. [Institute of Hydrology (United Kingdom)

    1994-03-01

    The hydrological analyses described in this paper formed an important part of the studies for the Victoria Project of which the Victoria Dam is the major component. The purpose of the hydrological studies was to provide consistent sets of river flow and climate data at the sites of the major components of the project, and to provide flood estimates for sizing the spillway and river diversion works. This paper outlines the approach used in the overall study, and then concentrates on aspects of specific relevance to the Victoria Dam. The main hydrological characteristics of the upper Mahaweli basin are presented as an introduction to the overall water balance; the humid climate made the appraisal of flow records relatively simple. Time series modelling was used to fill gaps in the observed flow records used for reservoir operation studies. The spillway design flood was based on the probable maximum precipitation (PMP) derived by maximizing a historic storm in which rainfall approaching the PMP covered most of the basin. Construction floods of moderate return period were estimated from a dimensionless analysis of regional flood records. The main lessons to be drawn are that water balance methods are of particular value in these humid monsoon conditions, while the ratio of the PMP to the maximum recorded storm is lower than would be the case in more arid regions. (author)

  11. The behaviour and brain function of the Cichlid fish ...

    African Journals Online (AJOL)

    ... the teleost forebrain houses a primitive limbic system the main functions of which would be general arousal and the selection of appropriate responses to the incoming external and endogenous (motivational) stimuli. Keywords: Brain Function, Teleost, telencephalon, Cichlid fish behaviour, limbic system, hippocampus ...

  12. Acute toxicity of phasetreat 4633 (demulsifier) against the cichlid ...

    African Journals Online (AJOL)

    The acute toxicity of phasetreat 4633 (Demulsifier) against the cichlid, Tilapia guineensis (fish) was determined using the Organisation of Economic Development and Cooperation (OECD) #203 protocol. Tilapia guineensis were exposed to concentrations of 6.25, 12.5, 25, 50 and 100 mg/l for 96 h. The 96h LC50 (19.32 ...

  13. Origin and evolution of B chromosomes in the cichlid fish Astatotilapia latifasciata based on integrated genomic analyses.

    Science.gov (United States)

    Valente, Guilherme T; Conte, Matthew A; Fantinatti, Bruno E A; Cabral-de-Mello, Diogo C; Carvalho, Robson F; Vicari, Marcelo R; Kocher, Thomas D; Martins, Cesar

    2014-08-01

    Approximately 15% of eukaryotes contain supernumerary B chromosomes. When present, B chromosomes frequently represent as much as 5% of the genome. Despite thousands of reports describing the distribution of supernumeraries in various taxa, a comprehensive theory for the origin, maintenance, and evolution of B chromosomes has not emerged. Here, we sequence the complete genomes of individual cichlid fish (Astatotilapia latifasciata) with and without B chromosomes, as well as microdissected B chromosomes, to identify DNA sequences on the B. B sequences were further analyzed through quantitative polymerase chain reaction and in situ hybridization. We find that the B chromosome contains thousands of sequences duplicated from essentially every chromosome in the ancestral karyotype. Although most genes on the B chromosome are fragmented, a few are largely intact, and we detect evidence that at least three of them are transcriptionally active. We propose a model in which the B chromosome originated early in the evolutionary history of Lake Victoria cichlids from a small fragment of one autosome. DNA sequences originating from several autosomes, including protein-coding genes and transposable elements, subsequently inserted into this proto-B. We propose that intact B chromosome genes involved with microtubule organization, kinetochore structure, recombination and progression through the cell cycle may play a role in driving the transmission of the B chromosome. Furthermore, our work suggests that karyotyping is an essential step prior to genome sequencing to avoid problems in genome assembly and analytical biases created by the presence of high copy number sequences on the B chromosome. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Complete mitochondrial DNA sequences of the threadfin cichlid (Petrochromis trewavasae and the blunthead cichlid (Tropheus moorii and patterns of mitochondrial genome evolution in cichlid fishes.

    Directory of Open Access Journals (Sweden)

    Christoph Fischer

    Full Text Available The cichlid fishes of the East African Great Lakes represent a model especially suited to study adaptive radiation and speciation. With several African cichlid genome projects being in progress, a promising set of closely related genomes is emerging, which is expected to serve as a valuable data base to solve questions on genotype-phenotype relations. The mitochondrial (mt genomes presented here are the first results of the assembly and annotation process for two closely related but eco-morphologically highly distinct Lake Tanganyika cichlids, Petrochromis trewavasae and Tropheus moorii. The genomic sequences comprise 16,588 bp (P. trewavasae and 16,590 bp (T. moorii, and exhibit the typical mitochondrial structure, with 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a non-coding control region. Analyses confirmed that the two species are very closely related with an overall sequence similarity of 96%. We analyzed the newly generated sequences in the phylogenetic context of 21 published labroid fish mitochondrial genomes. Consistent with other vertebrates, the D-loop region was found to evolve faster than protein-coding genes, which in turn are followed by the rRNAs; the tRNAs vary greatly in the rate of sequence evolution, but on average evolve the slowest. Within the group of coding genes, ND6 evolves most rapidly. Codon usage is similar among examined cichlid tribes and labroid families; although a slight shift in usage patterns down the gene tree could be observed. Despite having a clearly different nucleotide composition, ND6 showed a similar codon usage. C-terminal ends of Cox1 exhibit variations, where the varying number of amino acids is related to the structure of the obtained phylogenetic tree. This variation may be of functional relevance for Cox1 synthesis.

  15. Projecting the future levels of Lake Victoria

    Science.gov (United States)

    Vanderkelen, Inne; van Lipzig, Nicole; Thiery, Wim

    2017-04-01

    Lake Victoria directly sustains 30 million people living in its basin and 200 000 fishermen operating from its shores. As the one of the two sources of the Nile River, it also supports natural resources that impact the livelihood of over 300 million people living in the Nile basin. The outlet to the Nile is controlled by two hydropower dams. The water balance of Lake Victoria is controlled both by climatic conditions (precipitation and evaporation) and human management (dam outflow). Future climate simulations with a high resolution coupled lake-land-atmosphere model project decreasing mean precipitation and increasing evaporation over Lake Victoria. As these two are important factors in the water balance of Lake Victoria, these projected changes may induce a drop in future levels of Lake Victoria. Moreover, as Lake Victoria is also a relatively shallow lake, lake surface area may decrease as well. Here we present a water balance model for Lake Victoria that provides lake level and extent as output. We first force our model with observational input (new satellite products providing high quality precipitation and evaporation data) and evaluate it using measured lake levels. The skill of the model is subsequently assessed by forcing it with present-day regional climate simulations (CORDEX evaluation simulations). In a third step the future lake levels and surface area changes of Lake Victoria are simulated by forcing the model with CORDEX projections under RCP4.5 and 8.5. Finally, the role of human decisions regarding future dam outflow are investigated.

  16. New record of a fossil haplotilapiine cichlid from Central Kenya

    Directory of Open Access Journals (Sweden)

    Stefanie B. R. Penk

    2015-11-01

    Full Text Available African freshwater cichlids (Cichlidae: Pseudocrenilabrinae are well known for their exceptionally great diversity and their capability of rapid speciation as well as diverse adaptations. The extant Pseudocrenilabrinae can be grouped into 27 tribes, with more than 2000 species harbored in the Great Lakes and surrounding water bodies of the East African Rift System. However, this unique diversity is not reflected in the fossil record because fossil cichlids were predominantly reported based on isolated teeth and bones. Moreover, the few articulated specimens that are known have not been analyzed sufficiently with regard to their systematic position due to lack of comparative material. Here we present a new extraordinarily well-preserved cichlid fish fossil from the Middle Miocene (c. 12.5 Ma Lagerstaette Kabchore, which was recovered during recent fieldwork in the Tugen Hills (Baringo County, Central Kenya Rift. Based on the evidence of tricuspid teeth, the Kabchore fossil can be assigned to the subclade of the Haplotilapiines within the Pseudocrenilabrinae. The multivariate analysis of a large meristic data set, derived from 1014 extant specimens (encompassing all main lineages of Haplotilapiines and usage of available osteological data suggest that this fossil is most likely related to one of the three haplotilapiine tribes Tilapiini, Haplochromini or Oreochromini. Moreover, the fossil specimen closely resembles the extinct cichlid Oreochromis martyni (Van Couvering, 1982, previously described as species of Sarotherodon from the Middle Miocene alkaline Kapkiamu Lake in the Tugen Hills. The analysis of the greatly preserved fossil fish specimen from Kabchore definitely supplements the fragmentary fossil record of Africa’s Cichlidae and will afford new insights into its evolutionary history. We also expect that this fossil will be useful as calibration point for new divergence-time estimates.

  17. Parental Investment and sexual immune dimorphism in cichlids ans syngnathids

    OpenAIRE

    Keller, Isabel Salome

    2017-01-01

    I investigated how the interrelationship between parental investment and sexual immune dimorphism shape the evolution of parental care strategies within the cichlids and syngnathids. To understand why parental investment is displayed in such diversity in the animal kingdom, I assessed evolutionary and provisioning costs of parental investment in male pregnancy, biparental and maternal mouthbrooding. Additionally, to address the importance of parental investment, I tested for maternal effects ...

  18. Evolution of host specificity in monogeneans parasitizing African cichlid fish.

    Science.gov (United States)

    Mendlová, Monika; Šimková, Andrea

    2014-02-14

    The patterns and processes linked to the host specificity of parasites represent one of the central themes in the study of host-parasite interactions. We investigated the evolution and determinants of host specificity in gill monogeneans of Cichlidogyrus and Scutogyrus species parasitizing African freshwater fish of Cichlidae. We analyzed (1) the link between host specificity and parasite phylogeny, (2) potential morphometric correlates of host specificity (i.e. parasite body size and the morphometrics of the attachment apparatus), and (3) potential determinants of host specificity following the hypothesis of ecological specialization and the hypothesis of specialization on predictable resources (i.e. host body size and longevity were considered as measures of host predictability), and (4) the role of brooding behavior of cichlids in Cichlidogyrus and Scutogyrus diversification. No significant relationships were found between host specificity and phylogeny of Cichlidogyrus and Scutogyrus species. The mapping of host specificity onto the parasite phylogenetic tree revealed that an intermediate specialist parasitizing congeneric cichlid hosts represents the ancestral state for the Cichlidogyrus/Scutogyrus group. Only a weak relationship was found between the morphometry of the parasites' attachment apparatus and host specificity. Our study did not support the specialization on predictable resources or ecological specialization hypotheses. Nevertheless, host specificity was significantly related to fish phylogeny and form of parental care. Our results confirm that host specificity is not a derived condition for Cichlidogyrus/Scutogyrus parasites and may reflect other than historical constraints. Attachment apparatus morphometry reflects only partially (if at all) parasite adaptation to the host species, probably because of the morphological similarity of rapidly evolved cichlids (analyzed in our study). However, we showed that parental care behavior of cichlids may

  19. Lipase activity in the liver and digestive tract of some cichlids (Pisces ...

    African Journals Online (AJOL)

    The presence of lipase in the anterior section implies that lipid digestion takes place in this portion of the digestive tract of these fishes. This result shows that lipid digestion in these cichlids does not follow the same pattern as in higher vertebrates. Keywords: Cichlids, enzyme, lipase, liver and digestive tract. AJAZEB Vol.

  20. The Adaptive Radiation of Cichlid Fish in Lake Tanganyika: A Morphological Perspective

    Directory of Open Access Journals (Sweden)

    Tetsumi Takahashi

    2011-01-01

    Full Text Available Lake Tanganyika is the oldest of the Great Ancient Lakes in the East Africa. This lake harbours about 250 species of cichlid fish, which are highly diverse in terms of morphology, behaviour, and ecology. Lake Tanganyika's cichlid diversity has evolved through explosive speciation and is treated as a textbook example of adaptive radiation, the rapid differentiation of a single ancestor into an array of species that differ in traits used to exploit their environments and resources. To elucidate the processes and mechanisms underlying the rapid speciation and adaptive radiation of Lake Tanganyika's cichlid species assemblage it is important to integrate evidence from several lines of research. Great efforts have been, are, and certainly will be taken to solve the mystery of how so many cichlid species evolved in so little time. In the present review, we summarize morphological studies that relate to the adaptive radiation of Lake Tanganyika's cichlids and highlight their importance for understanding the process of adaptive radiation.

  1. Mechanisms of species divergence through visual adaptation and sexual selection:Perspectives from a cichlid model system

    Directory of Open Access Journals (Sweden)

    Martine E. MAAN, Ole SEEHAUSEN

    2010-06-01

    Full Text Available The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences are directly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process, because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. When divergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence. Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selection against intermediate phenotypes that are maladapted to their (sensory environment. For Lake Victoria cichlids, the visual environment constitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigate the direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours (red and blue in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extract general principles, and discuss future perspectives [Current Zoology 56 (3: 285–299, 2010].

  2. Spiraal : uus Victoria & Alberti muuseum Londonis

    Index Scriptorium Estoniae

    1998-01-01

    Daniel Libeskindi projekt Victoria & Alberti Muuseumi laiendamiseks on põhjustanud konservatiivsete londonlaste pahameele, kuid kutsunud esile ka hulgaliselt toetusavaldusi. Muuseumi uus osa (kokkuvarisemise piiril näiva ehitisena) peaks külastajaile avatama 2004. a.

  3. Monogeneans in introduced and native cichlids in México: evidence for transfer.

    Science.gov (United States)

    Jiménez-García, M I; Vidal-Martínez, V M; López-Jiménez, S

    2001-08-01

    We examined 2 cichlid fish species native to México, Cichlasoma callolepis and C. fenestratum, and 2 introduced African cichlids, Oreochromis aureus and O. niloticus, from 3 localities in southeastern México for monogeneans. Six monogenean species infected the African cichlids: Cichlidogyrus haplochromii, C. dossoui, C. longicornis longicornis, C. sclerosus, C. tilapiae, and Enterogyrus malmbergi. We found all these parasite species, except C. haplochromii and C. dossoui, on the native C. fenestratum and C. callolepis. Prevalences of Cichlidogyrus spp. were 3-10% and abundances ranged from 0.03 +/- 0.2 to 0.1 +/- 0.3 for native cichlids. We only recovered a single E. malmbergi from 1 C. callolepis. We found Sciadicleithrum bravohollisae, a monogenean of native Cichlasoma spp., on the gills of the introduced O. aureus from Lake Catemaco (prevalence 3%, abundance 0.03 +/- 0.2). Although prevalence and abundance in atypical hosts were fairly low, the present findings provide evidence of monogenean transfer from African to American cichlids and vice versa. This is the first record of exotic monogeneans in the genus Cichlidogyrus and Enterogyrus infecting native American cichlid fish. It is also the first record from southeastern México of a native American monogenean infecting introduced African cichlids.

  4. The Victoria Project, Sri Lanka: Victoria Power-Station. [Hydroelectric power

    Energy Technology Data Exchange (ETDEWEB)

    Creber, B. (Sir Alexander Gibb and Partners (GB))

    1991-04-01

    The Victoria Hydroelectric Power-Station forms part of the Victoria Project on the Mahaweli Ganga in Sri Lanka and it provides the country's largest single power source. The Paper describes the planning, design and construction of the civil engineering works, including problems encountered, and also describes, in outline, the electrical and mechanical works. (Author).

  5. Repeatability and Heritability of Behavioural Types in a Social Cichlid

    Directory of Open Access Journals (Sweden)

    Noémie Chervet

    2011-01-01

    Full Text Available Aim. The quantitative genetics underlying correlated behavioural traits (‘‘animal personality’’ have hitherto been studied mainly in domesticated animals. Here we report the repeatability ( and heritability (ℎ2 of behavioural types in the highly social cichlid fish Neolamprologus pulcher. Methods. We tested 1779 individuals repeatedly and calculated the ℎ2 of behavioural types by variance components estimation (GLMM REML, using 1327 offspring from 162 broods from 74 pairs. Results. Repeatability of behavioural types was significant and considerable (0.546, but declined from 0.83 between tests conducted on the same day, to 0.19 on tests conducted up to 1201 days apart. All ℎ2 estimates were significant but low (e.g., pair identity ℎ2=0.15±0.03 SE. Additionally, we found significant variation between broods nested within the parent(s, but these were not related to several environmental factors tested. Conclusions. We conclude that despite a considerable , ℎ2 in this cichlid species is low, and variability in behavioural type appears to be strongly affected by other (nongenetic effects.

  6. Sexual selection determines parental care patterns in cichlid fishes.

    Science.gov (United States)

    Gonzalez-Voyer, Alejandro; Fitzpatrick, John L; Kolm, Niclas

    2008-08-01

    Despite a massive research effort, our understanding of why, in most vertebrates, males compete for mates and females care for offspring remains incomplete. Two alternative hypotheses have been proposed to explain the direction of causality between parental care and sexual selection. Traditionally, sexual selection has been explained as a consequence of relative parental investment, where the sex investing less will compete for the sex investing more. However, a more recent model suggests that parental care patterns result from sexual selection acting on one sex favoring mating competition and lower parental investment. Using species-level comparative analyses on Tanganyikan cichlid fishes we tested these alternative hypotheses employing a proxy of sexual selection based on mating system, sexual dichromatism, and dimorphism data. First, while controlling for female reproductive investment, we found that species with intense sexual selection were associated with female-only care whereas species with moderate sexual selection were associated with biparental care. Second, using contingency analyses, we found that, contrary to the traditional view, evolutionary changes in parental care type are dependent on the intensity of sexual selection. Hence, our results support the hypothesis that sexual selection determines parental care patterns in Tanganyikan cichlid fishes.

  7. Evolutionary History of Lake Tanganyika's Predatory Deepwater Cichlids.

    Science.gov (United States)

    Kirchberger, Paul C; Sefc, Kristina M; Sturmbauer, Christian; Koblmüller, Stephan

    2012-01-01

    Hybridization among littoral cichlid species in Lake Tanganyika was inferred in several molecular phylogenetic studies. The phenomenon is generally attributed to the lake level-induced shoreline and habitat changes. These allow for allopatric divergence of geographically fragmented populations alternating with locally restricted secondary contact and introgression between incompletely isolated taxa. In contrast, the deepwater habitat is characterized by weak geographic structure and a high potential for gene flow, which may explain the lower species richness of deepwater than littoral lineages. For the same reason, divergent deepwater lineages should have evolved strong intrinsic reproductive isolation already in the incipient stages of diversification, and, consequently, hybridization among established lineages should have been less frequent than in littoral lineages. We test this hypothesis in the endemic Lake Tanganyika deepwater cichlid tribe Bathybatini by comparing phylogenetic trees of Hemibates and Bathybates species obtained with nuclear multilocus AFLP data with a phylogeny based on mitochondrial sequences. Consistent with our hypothesis, largely congruent tree topologies and negative tests for introgression provided no evidence for introgressive hybridization between the deepwater taxa. Together, the nuclear and mitochondrial data established a well-supported phylogeny and suggested ecological segregation during speciation.

  8. Evolution of brain-body allometry in Lake Tanganyika cichlids.

    Science.gov (United States)

    Tsuboi, Masahito; Kotrschal, Alexander; Hayward, Alexander; Buechel, Severine Denise; Zidar, Josefina; Løvlie, Hanne; Kolm, Niclas

    2016-07-01

    Brain size is strongly associated with body size in all vertebrates. This relationship has been hypothesized to be an important constraint on adaptive brain size evolution. The essential assumption behind this idea is that static (i.e., within species) brain-body allometry has low ability to evolve. However, recent studies have reported mixed support for this view. Here, we examine brain-body static allometry in Lake Tanganyika cichlids using a phylogenetic comparative framework. We found considerable variation in the static allometric intercept, which explained the majority of variation in absolute and relative brain size. In contrast, the slope of the brain-body static allometry had relatively low variation, which explained less variation in absolute and relative brain size compared to the intercept and body size. Further examination of the tempo and mode of evolution of static allometric parameters confirmed these observations. Moreover, the estimated evolutionary parameters indicate that the limited observed variation in the static allometric slope could be a result of strong stabilizing selection. Overall, our findings suggest that the brain-body static allometric slope may represent an evolutionary constraint in Lake Tanganyika cichlids. © 2016 The Author(s).

  9. Colour variation in cichlid fish: Developmental mechanisms, selective pressures and evolutionary consequences☆

    Science.gov (United States)

    Maan, Martine E.; Sefc, Kristina M.

    2013-01-01

    Cichlid fishes constitute one of the most species-rich families of vertebrates. In addition to complex social behaviour and morphological versatility, they are characterised by extensive diversity in colouration, both within and between species. Here, we review the cellular and molecular mechanisms underlying colour variation in this group and the selective pressures responsible for the observed variation. We specifically address the evidence for the hypothesis that divergence in colouration is associated with the evolution of reproductive isolation between lineages. While we conclude that cichlid colours are excellent models for understanding the role of animal communication in species divergence, we also identify taxonomic and methodological biases in the current research effort. We suggest that the integration of genomic approaches with ecological and behavioural studies, across the entire cichlid family and beyond it, will contribute to the utility of the cichlid model system for understanding the evolution of biological diversity. PMID:23665150

  10. The oldest fossil cichlids (Teleostei: Perciformes): indication of a 45 million-year-old species flock.

    Science.gov (United States)

    Murray, A. M.

    2001-01-01

    Five closely related species of fossil cichlids collected from an Eocene site in Tanzania, East Africa, represent the oldest known cichlids. The specimens are whole-body, articulated fishes that are extremely well preserved and, therefore, have the potential to add to our knowledge of the history of this family. Modern cichlids are particularly well known for the numerous species flocks of the East African Great Lakes. A great deal of research is ongoing regarding all aspects of the fishes in these flocks, including their evolutionary history The new collection of fossils reported here is interpreted as representing a species flock that arose in a small crater lake. These fossils indicate that cichlids' ability to form species flocks evolved early in the history of this family. PMID:11321055

  11. total mercury concentration in common fish species of lake victoria ...

    African Journals Online (AJOL)

    Total mercury (THg) concentration was analysed in muscles of common fish species of Lake. Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption. Spectrophotometric ... INTRODUCTION. The Lake Victoria ...

  12. Seabed surveys of Victoria harbour, Mahe, Seychelles

    Digital Repository Service at National Institute of Oceanography (India)

    Hashimi, N.H.; Wagle, B.G.

    The seabed surveys in the Victoria Harbour, Mahe, Seychelles shows that the prominent feature is the navigational channel aligned in the northeast-southwest direction with a width varying from 300 to 450m. The depth in the channel ranges from 14...

  13. Geography and Geographical Education in Victoria

    Science.gov (United States)

    Kriewaldt, Jeana

    2006-01-01

    Victoria has just emerged from 10 years where Geography has been one of three strands in the key learning area of Studies of Society and Environment (SOSE). The overarching framework emerged from an attempt to develop a national curriculum. Whilst the national curriculum was rejected by Australian state and territories who each hold legislative…

  14. within the lake victoria basin, tanzania

    African Journals Online (AJOL)

    ABSTRACT. Levels of nitrates (NOg-N) and phosphates (PO4~P) in some satellite lakes within the Lake. Victoria basin were determined in Kagera (Lake Burigt), in Mara (River Mara) and in Mwanza region (Lake Malimbe) during August/September 2002 (dry season) and January/February 2003. (wet season).

  15. D Digital Cadastre Journey in Victoria, Australia

    Science.gov (United States)

    Shojaei, D.; Olfat, H.; Briffa, M.; Rajabifard, A.

    2017-10-01

    Land development processes today have an increasing demand to access three-dimensional (3D) spatial information. Complex land development may need to have a 3D model and require some functions which are only possible using 3D data. Accordingly, the Intergovernmental Committee on Surveying and Mapping (ICSM), as a national body in Australia provides leadership, coordination and standards for surveying, mapping and national datasets has developed the Cadastre 2034 strategy in 2014. This strategy has a vision to develop a cadastral system that enables people to readily and confidently identify the location and extent of all rights, restrictions and responsibilities related to land and real property. In 2014, the land authority in the state of Victoria, Australia, namely Land Use Victoria (LUV), has entered the challenging area of designing and implementing a 3D digital cadastre focused on providing more efficient and effective services to the land and property industry. LUV has been following the ICSM 2034 strategy which requires developing various policies, standards, infrastructures, and tools. Over the past three years, LUV has mainly focused on investigating the technical aspect of a 3D digital cadastre. This paper provides an overview of the 3D digital cadastre investigation progress in Victoria and discusses the challenges that the team faced during this journey. It also addresses the future path to develop an integrated 3D digital cadastre in Victoria.

  16. CLARIIDAE) FROM THE MWANZA GULF, LAKE VICTORIA

    African Journals Online (AJOL)

    ABSTRACT. Seventeen species of parasites were recovered from 107 I Clarias gariepinus examined flom the. Mwanza Gulf of Lake Victoria. The parasite fauna comprised of four ectoparasites, a. Monogenea, Hirudinea, crustacean and a Digenea,' and fourteen endoparasites, five nematodes,. five trematodes and three ...

  17. Demographic modelling with whole-genome data reveals parallel origin of similar Pundamilia cichlid species after hybridization.

    Science.gov (United States)

    Meier, Joana I; Sousa, Vitor C; Marques, David A; Selz, Oliver M; Wagner, Catherine E; Excoffier, Laurent; Seehausen, Ole

    2017-01-01

    Modes and mechanisms of speciation are best studied in young species pairs. In older taxa, it is increasingly difficult to distinguish what happened during speciation from what happened after speciation. Lake Victoria cichlids in the genus Pundamilia encompass a complex of young species and polymorphic populations. One Pundamilia species pair, P. pundamilia and P. nyererei, is particularly well suited to study speciation because sympatric population pairs occur with different levels of phenotypic differentiation and reproductive isolation at different rocky islands within the lake. Genetic distances between allopatric island populations of the same nominal species often exceed those between the sympatric species. It thus remained unresolved whether speciation into P. nyererei and P. pundamilia occurred once, followed by geographical range expansion and interspecific gene flow in local sympatry, or if the species pair arose repeatedly by parallel speciation. Here, we use genomic data and demographic modelling to test these alternative evolutionary scenarios. We demonstrate that gene flow plays a strong role in shaping the observed patterns of genetic similarity, including both gene flow between sympatric species and gene flow between allopatric populations, as well as recent and early gene flow. The best supported model for the origin of P. pundamilia and P. nyererei population pairs at two different islands is one where speciation happened twice, whereby the second speciation event follows shortly after introgression from an allopatric P. nyererei population that arose earlier. Our findings support the hypothesis that very similar species may arise repeatedly, potentially facilitated by introgressed genetic variation. © 2016 John Wiley & Sons Ltd.

  18. Community assembly in Lake Tanganyika cichlid fish : Quantifying the contributions of both niche-based and neutral processes

    NARCIS (Netherlands)

    Janzen, Thijs; Alzate Vallejo, Adriana; Muschick, Moritz; Maan, Martine E; Plas ,van der Fons; Etienne, Rampal S

    The cichlid family features some of the most spectacular examples of adaptive radiation. Evolutionary studies have highlighted the importance of both trophic adaptation and sexual selection in cichlid speciation. However, it is poorly understood what processes drive the composition and diversity of

  19. Adaptive phenotypic plasticity in the Midas cichlid fish pharyngeal jaw and its relevance in adaptive radiation

    Directory of Open Access Journals (Sweden)

    Salzburger Walter

    2011-04-01

    Full Text Available Abstract Background Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp. in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. Results We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. Conclusions The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated - among

  20. Directional selection has shaped the oral jaws of Lake Malawi cichlid fishes.

    Science.gov (United States)

    Albertson, R Craig; Streelman, J Todd; Kocher, Thomas D

    2003-04-29

    East African cichlid fishes represent one of the most striking examples of rapid and convergent evolutionary radiation among vertebrates. Models of ecological speciation would suggest that functional divergence in feeding morphology has contributed to the origin and maintenance of cichlid species diversity. However, definitive evidence for the action of natural selection has been missing. Here we use quantitative genetics to identify regions of the cichlid genome responsible for functionally important shape differences in the oral jaw apparatus. The consistent direction of effects for individual quantitative trait loci suggest that cichlid jaws and teeth evolved in response to strong, divergent selection. Moreover, several chromosomal regions contain a disproportionate number of quantitative trait loci, indicating a prominent role for pleiotropy or genetic linkage in the divergence of this character complex. Of particular interest are genomic intervals with concerted effects on both the length and height of the lower jaw. Coordinated changes in this area of the oral jaw apparatus are predicted to have direct consequences for the speed and strength of jaw movement. Taken together, our results imply that the rapid and replicative nature of cichlid trophic evolution is the result of directional selection on chromosomal packages that encode functionally linked aspects of the craniofacial skeleton.

  1. Mathematical Problems in Biology : Victoria Conference

    CERN Document Server

    1974-01-01

    A conference on "Some Mathematical Problems in Biology" was held at the University of Victoria, Victoria, B. C. , Canada, from May 7 - 10, 1973. The participants and invited speakers were mathematicians interested in problems of a biological nature, and scientists actively engaged in developing mathematical models in biological fields. One aim of the conference was to attempt to assess what the recent rapid growth of mathematical interaction with the biosciences has accomplished and may accomplish in the near future. The conference also aimed to expose the problems of communication bet~",een mathematicians and biological scientists, and in doing so to stimulate the interchange of ideas. It was recognised that the topic spans an enormous breadth, and little attempt was made to balance the very diverse areas. Widespread active interest was shown in the conference, and just over one hundred people registered. The varied departments and institutions across North America from which the participants came made it bo...

  2. Pancam Peek into 'Victoria Crater' (Stereo)

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Left-eye view of a stereo pair for PIA08776 [figure removed for brevity, see original site] Right-eye view of a stereo pair for PIA08776 A drive of about 60 meters (about 200 feet) on the 943rd Martian day, or sol, of Opportunity's exploration of Mars' Meridiani Planum region (Sept. 18, 2006) brought the NASA rover to within about 50 meters (about 160 feet) of the rim of 'Victoria Crater.' This crater has been the mission's long-term destination for the past 21 Earth months. Opportunity reached a location from which the cameras on top of the rover's mast could begin to see into the interior of Victoria. This stereo anaglyph was made from frames taken on sol 943 by the panoramic camera (Pancam) to offer a three-dimensional view when seen through red-blue glasses. It shows the upper portion of interior crater walls facing toward Opportunity from up to about 850 meters (half a mile) away. The amount of vertical relief visible at the top of the interior walls from this angle is about 15 meters (about 50 feet). The exposures were taken through a Pancam filter selecting wavelengths centered on 750 nanometers. Victoria Crater is about five times wider than 'Endurance Crater,' which Opportunity spent six months examining in 2004, and about 40 times wider than 'Eagle Crater,' where Opportunity first landed. The great lure of Victoria is the expectation that a thick stack of geological layers will be exposed in the crater walls, potentially several times the thickness that was previously studied at Endurance and therefore, potentially preserving several times the historical record.

  3. Implementation of the victoria bowel performance scale.

    Science.gov (United States)

    Hawley, Philippa; Barwich, Doris; Kirk, Lisa

    2011-12-01

    There is a lack of evidence to guide constipation management in patients receiving palliative care. Data collection requires the systematic use of validated assessment tools. The objective of this study was to assess the usefulness of the Victoria Bowel Performance Scale (BPS) as an audit tool. Charts were reviewed before and after the implementation of a program to monitor constipation through repeated use of the Victoria Bowel Scale. The program was initiated at three oncology pain and symptom management clinics, four palliative care units, and four residential hospices. An additional "control" palliative care unit introduced new nursing assessment tools without the new scale. The Victoria BPS was recorded at 86% of 192 postimplementation outpatient clinic visits and was easy to use in this setting. Documentation of bowel performance at comparable visits improved from 44% to 66% (Passessment tool, uniquely incorporating the patient's usual bowel function. Modifications to the scale have been made to improve clarity and allow for the expected drop in bowel activity seen in end-of-life care. Considerable educational effort and appropriate organization of the charts are required for optimal implementation. The proportion of revised BPS scores ranging from -1 to +1 is proposed as an indicator of satisfactory bowel management for clinical, audit, and research purposes. Copyright © 2011 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

  4. Helpful female subordinate cichlids are more likely to reproduce.

    Directory of Open Access Journals (Sweden)

    Dik Heg

    Full Text Available BACKGROUND: In many cooperatively breeding vertebrates, subordinates assist a dominant pair to raise the dominants' offspring. Previously, it has been suggested that subordinates may help in payment for continued residency on the territory (the 'pay-to-stay hypothesis', but payment might also be reciprocated or might allow subordinates access to reproductive opportunities. METHODOLOGY/PRINCIPAL FINDINGS: We measured dominant and subordinate female alloparental brood care and reproductive success in four separate experiments and show that unrelated female dominant and subordinate cichlid fish care for each other's broods (alloparental brood care, but that there is no evidence for reciprocal 'altruism' (no correlation between alloparental care received and given. Instead, subordinate females appear to pay with alloparental care for own direct reproduction. CONCLUSIONS/SIGNIFICANCE: Our results suggest subordinate females pay with alloparental care to ensure access to the breeding substrate and thereby increase their opportunities to lay their own clutches. Subordinates' eggs are laid, on average, five days after the dominant female has produced her first brood. We suggest that immediate reproductive benefits need to be considered in tests of the pay-to-stay hypothesis.

  5. Paternity of subordinates raises cooperative effort in cichlids.

    Directory of Open Access Journals (Sweden)

    Rick Bruintjes

    Full Text Available In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship.We show that: (i male subordinates gained paternity in 27.8% of all clutches and (ii if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male were detected on parentage and on helping behaviour.This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.

  6. An improved genome reference for the African cichlid, Metriaclima zebra.

    Science.gov (United States)

    Conte, Matthew A; Kocher, Thomas D

    2015-09-22

    Problems associated with using draft genome assemblies are well documented and have become more pronounced with the use of short read data for de novo genome assembly. We set out to improve the draft genome assembly of the African cichlid fish, Metriaclima zebra, using a set of Pacific Biosciences SMRT sequencing reads corresponding to 16.5× coverage of the genome. Here we characterize the improvements that these long reads allowed us to make to the state-of-the-art draft genome previously assembled from short read data. Our new assembly closed 68% of the existing gaps and added 90.6 Mbp of new non-gap sequence to the existing draft assembly of M. zebra. Comparison of the new assembly to the sequence of several bacterial artificial chromosome clones confirmed the accuracy of the new assembly. The closure of sequence gaps revealed thousands of new exons, allowing significant improvement in gene models. We corrected one known misassembly, and identified and fixed other likely misassemblies. 63.5 Mbp (70%) of the new sequence was classified as repetitive and the new sequence allowed for the assembly of many more transposable elements. Our improvements to the M. zebra draft genome suggest that a reasonable investment in long reads could greatly improve many comparable vertebrate draft genome assemblies.

  7. Secondary contact seeds phenotypic novelty in cichlid fishes.

    Science.gov (United States)

    Nichols, Paul; Genner, Martin J; van Oosterhout, Cock; Smith, Alan; Parsons, Paul; Sungani, Harold; Swanstrom, Jennifer; Joyce, Domino A

    2015-01-07

    Theory proposes that genomic admixture between formerly reproductively isolated populations can generate phenotypic novelty for selection to act upon. Secondary contact may therefore be a significant promoter of phenotypic novelty that allows species to overcome environmental challenges and adapt to novel environments, including during adaptive radiation. To date, this has largely been considered from the perspective of interspecific hybridization at contact zones. However, it is also possible that this process occurs more commonly between natural populations of a single species, and thus its importance in adaptive evolution may have been underestimated. In this study, we tested the consequences of genomic introgression during apparent secondary contact between phenotypically similar lineages of the riverine cichlid fish Astatotilapia calliptera. We provide population genetic evidence of a secondary contact zone in the wild, and then demonstrate using mate-choice experiments that both lineages can reproduce together successfully in laboratory conditions. Finally, we show that genomically admixed individuals display extreme phenotypes not observed in the parental lineages. Collectively, the evidence shows that secondary contact can drive the evolution of phenotypic novelty, suggesting that pulses of secondary contact may repeatedly seed genetic novelty, which when coupled with ecological opportunity could promote rapid adaptive evolution in natural circumstances.

  8. Spawning Coordination of Mates in a Shell Brooding Cichlid

    Directory of Open Access Journals (Sweden)

    Dolores Schütz

    2012-01-01

    Full Text Available Aim. External fertilisation requires synchronisation of gamete release between the two sexes. Adequate synchronisation is essential in aquatic media because sperm is very short-lived in water. In the cichlid Lamprologus callipterus, fertilisation of the eggs takes place inside an empty snail shell, where females stay inside the shell and males have to ejaculate into the shell opening. This spawning pattern makes the coordination of gamete release difficult. Methods. This study examined the synchronisation of males and females during egg laying. Results. The results showed that the male initiates each spawning sequence and that sperm release and egg laying are very well synchronised. 68% of all sperm releases occurred at exactly the same time when the female laid an egg, and 99% of ejaculations occurred within ±5 seconds from egg deposition. On average 95 eggs are laid one by one with intervals of several minutes between subsequent eggs, leading to a total spawning duration in excess of six hours. Conclusions. We discuss this exceptional spawning pattern and how it might reflect a conflict between the sexes, with males attempting to induce egg laying and females extending the egg laying period to raise the chance for parasitic males to participate in spawning.

  9. Social familiarity modulates personality trait in a cichlid fish

    Science.gov (United States)

    Galhardo, L.; Vitorino, A.; Oliveira, R. F.

    2012-01-01

    Personality traits, such as exploration–avoidance, are expected to be adaptive in a given context (e.g. low-risk environment) but to be maladaptive in others (e.g. high-risk environment). Therefore, it is expected that personality traits are flexible and respond to environmental fluctuations, given that consistency across different contexts is maintained, so that the relative individual responses in relation to others remains the same (i.e. although the magnitude of the response varies the differences between high and low responders are kept). Here, we tested the response of male cichlid fish (Oreochromis mossambicus) to a novel object (NO) in three different social contexts: (i) social isolation, (ii) in the presence of an unfamiliar conspecific, and (iii) in the presence of a familiar conspecific. Males in the familiar treatment exhibited more exploratory behaviour and less neophobia than males in either the unfamiliar or the social isolation treatments. However, there were no overall correlations in individual behaviour across the three treatments, suggesting a lack of consistency in exploration–avoidance as measured by the NO test in this species. Moreover, there were no differences in cortisol responsiveness to an acute stressor between the three treatments. Together, these results illustrate how behavioural traits usually taken as measures of personality may exhibit significant flexibility and lack the expected consistency across different social contexts. PMID:22859562

  10. Paternity of subordinates raises cooperative effort in cichlids.

    Science.gov (United States)

    Bruintjes, Rick; Bonfils, Danielle; Heg, Dik; Taborsky, Michael

    2011-01-01

    In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship. We show that: (i) male subordinates gained paternity in 27.8% of all clutches and (ii) if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male) were detected on parentage and on helping behaviour. This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.

  11. Parasitic infections in ornamental cichlid fish in the Peruvian Amazon.

    Science.gov (United States)

    Aguinaga, Jefferson Yunis; Marcusso, Paulo Fernandes; Claudiano, Gustavo da Silva; Lima, Bruno Tadeu Marotta; Marotta, Bruno L; Sebastião, Fernanda de Alexandre; Fernandes, João Batista Kochenborger; de Moraes, Flávio Ruas; de Moraes, Julieta Rodini Engracia

    2015-01-01

    The aim of this study was to evaluate the prevalence and seasonal distribution of the main parasite species in Amazonian ornamental cichlids that affect their trade. The study was conducted from August 2007 to September 2009. We sampled 3042 specimens from 9 different species, of which 9.47% had at least one type of external parasite. 81.25% of the cases occurred in the dry season. Crenicichla anthurus (28.57%) was the most parasitized, followed by Aequidens diadema (26.32%), Pterophyllum scalare (22.69%), Cichlasoma sp. (9.52%), Apistogramma sp. (3.88%) and Symphysodon aequifasciatus (3.66%). Monogenea was the most abundant group of parasites, occurring in 66.67% of the cases, of which 96.88% occurred in the dry season. This parasite infested 95.68% of Pterophyllum scalare, 76.67% of Apistogramma sp, 33.33% of Cichlasoma sp. and 23.81% of Symphysodon aequifasciatus cases. Ichthyophthirius multifiliis infested 100% of Aequidens diadema, 76.19% of Symphysodon aequifasciatus, 66.67% of Cichlasoma sp, 41.67% of Crenicichla anthurus and 23.33% of Apistogramma sp cases. Myxosporidia infested 58.33% of Crenicichla anthurus. Trichodina infested 4.32% of Pterophyllum scalare. The prevalence of these parasites is related to the season, preferred habitat, fish behavior, individual susceptibility and handling of animals during transportation by fishermen.

  12. Accelerated Evolution and Functional Divergence of the Dim Light Visual Pigment Accompanies Cichlid Colonization of Central America.

    Science.gov (United States)

    Hauser, Frances E; Ilves, Katriina L; Schott, Ryan K; Castiglione, Gianni M; López-Fernández, Hernán; Chang, Belinda S W

    2017-10-01

    Cichlids encompass one of the most diverse groups of fishes in South and Central America, and show extensive variation in life history, morphology, and colouration. While studies of visual system evolution in cichlids have focussed largely on the African rift lake species flocks, Neotropical cichlids offer a unique opportunity to investigate visual system evolution at broader temporal and geographic scales. South American cichlid colonization of Central America has likely promoted accelerated rates of morphological evolution in Central American lineages as they encountered reduced competition, renewed ecological opportunity, and novel aquatic habitats. To investigate whether such transitions have influenced molecular evolution of vision in Central American cichlids, we sequenced the dim-light rhodopsin gene in 101 Neotropical cichlid species, spanning the diversity of the clade. We find strong evidence for increased rates of evolution in Central American cichlid rhodopsin relative to South American lineages, and identify several sites under positive selection in rhodopsin that likely contribute to adaptation to different photic environments. We expressed a Neotropical cichlid rhodopsin protein invitro for the first time, and found that while its spectral tuning properties were characteristic of typical vertebrate rhodopsin pigments, the rate of decay of its active signalling form was much slower, consistent with dim light adaptation in other vertebrate rhodopsins. Using site-directed mutagenesis combined with spectroscopic assays, we found that a key amino acid substitution present in some Central American cichlids accelerates the rate of decay of active rhodopsin, which may mediate adaptation to clear water habitats. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Gender Integration in the Management of the Lake Victoria Fisheries ...

    African Journals Online (AJOL)

    The riparian governments of Lake Victoria have adopted co-management approach in fisheries management. This paper discusses gender mainstreaming in fisheries management of Lake Victoria, user rights, successes and challenges of the process. This paper has used gender-disaggregated data from several studies ...

  14. Large group size yields group stability in the cooperatively breeding cichlid Neolamprologus pulcher

    NARCIS (Netherlands)

    Heg, D.; Bachar, Z; Taborsky, M; Brouwer, L.

    2005-01-01

    Group size has been shown to positively influence survival of group members in many cooperatively breeding vertebrates, including the Lake Tanganyika cichlid Neolamprologus pulcher, suggesting Allee effects. However, long-term data are scarce to test how these survival differences translate into

  15. On gonads and reproductive behaviour in the cichlid fish Aequidens portalegrensis (Hensel)

    NARCIS (Netherlands)

    Polder, Johan Jan Willem

    1971-01-01

    In this paper on the cichlid fish Aequidensp ortalegrensis,in formation is given on 1) the anatomy and histology of the gonads, 2) the functional anatomy of the accessory organs, 3) the occurrence of cyclical changes in the gonads, 4) the mutual behaviour of male and female under different

  16. Depth and substratum differentiations among coexisting herbivorous cichlids in Lake Tanganyika.

    Science.gov (United States)

    Hata, Hiroki; Ochi, Haruki

    2016-11-01

    Cichlid fish in Lake Tanganyika represent a system of adaptive radiation in which eight ancestral lineages have diversified into hundreds of species through adaptation to various niches. However, Tanganyikan cichlids have been thought to be oversaturated, that is, the species number exceeds the number of niches and ecologically equivalent and competitively even species coexist. However, recent studies have shed light on niche segregation on a finer scale among apparently equivalent species. We observed depth and substratum preferences of 15 herbivorous cichlids from four ecomorphs (i.e. grazer, browser, scraper and scooper) on a rocky littoral slope for 14 years. Depth differentiation was detected among grazers that defended feeding territories and among browsers with feeding territories. Cichlid species having no feeding territory also showed specificity on depth and substratum, resulting in habitat segregation among species that belong to the same ecomorph. Phylogenetically close species did not occupy adjacent depths, nor the opposite depth zones. Our findings suggest that apparently equivalent species of the same ecomorph coexist parapatrically along depth on a few-metre scale, or coexist with different substratum preferences on the rocky shore, and this niche segregation may have been acquired by competition between encountering equivalent species through repetitive lake-level fluctuations.

  17. Mitogenomic evaluation of the historical biogeography of cichlids toward reliable dating of teleostean divergences

    Directory of Open Access Journals (Sweden)

    Miya Masaki

    2008-07-01

    Full Text Available Abstract Background Recent advances in DNA sequencing and computation offer the opportunity for reliable estimates of divergence times between organisms based on molecular data. Bayesian estimations of divergence times that do not assume the molecular clock use time constraints at multiple nodes, usually based on the fossil records, as major boundary conditions. However, the fossil records of bony fishes may not adequately provide effective time constraints at multiple nodes. We explored an alternative source of time constraints in teleostean phylogeny by evaluating a biogeographic hypothesis concerning freshwater fishes from the family Cichlidae (Perciformes: Labroidei. Results We added new mitogenomic sequence data from six cichlid species and conducted phylogenetic analyses using a large mitogenomic data set. We found a reciprocal monophyly of African and Neotropical cichlids and their sister group relationship to some Malagasy taxa (Ptychochrominae sensu Sparks and Smith. All of these taxa clustered with a Malagasy + Indo/Sri Lankan clade (Etroplinae sensu Sparks and Smith. The results of the phylogenetic analyses and divergence time estimations between continental cichlid clades were much more congruent with Gondwanaland origin and Cretaceous vicariant divergences than with Cenozoic transmarine dispersal between major continents. Conclusion We propose to add the biogeographic assumption of cichlid divergences by continental fragmentation as effective time constraints in dating teleostean divergence times. We conducted divergence time estimations among teleosts by incorporating these additional time constraints and achieved a considerable reduction in credibility intervals in the estimated divergence times.

  18. Evolution of egg dummies in Tanganyikan cichlid fishes: the roles of parental care and sexual selection.

    Science.gov (United States)

    Amcoff, M; Gonzalez-Voyer, A; Kolm, N

    2013-11-01

    Sexual selection has been suggested to be an important driver of speciation in cichlid fishes of the Great Lakes of Africa, and the presence of male egg dummies is proposed to have played a key role. Here, we investigate how mouthbrooding and egg dummies have evolved in Tanganyikan cichlids, the lineage which seeded the other African radiations, with a special emphasis on the egg dummies. Using modern phylogenetic comparative analyses and a phylogeny including 86% of the 200 described species, we provide formal evidence demonstrating correlated evolution between mouthbrooding and egg dummies in Tanganyikan cichlids. These results concur with existing evidence, suggesting that egg dummies have evolved through sensory exploitation. We also demonstrate that there is a strong evolutionary correlation between the presence of egg dummies and both pre- and post-copulatory sexual selection. Moreover, egg dummy evolution was contingent on the intensity of pre- and post-copulatory sexual selection in Tanganyikan cichlids. In sum, our results provide evidence supporting the hypothesis of egg dummies evolving through sensory exploitation and highlight the role of sexual selection in favouring the evolution and maintenance of this trait. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  19. The Monogenean Parasite Fauna of Cichlids: A Potential Tool for Host Biogeography

    OpenAIRE

    Antoine Pariselle; Boeger, Walter A.; Jos Snoeks; Bilong Bilong,Charles F.; Serge Morand; Vanhove, Maarten P. M.

    2011-01-01

    We discuss geographical distribution and phylogeny of Dactylogyridea (Monogenea) parasitizing Cichlidae to elucidate their hosts' history. Although mesoparasitic Monogenea (Enterogyrus spp.) show typical vicariant distribution, ectoparasitic representatives from different continents are not considered sister taxa, hence their distribution cannot result from vicariance alone. Because of the close host-parasite relationship, this might indicate that present-day cichlid distribution may also ref...

  20. Alternative Reproductive Tactics in the Shell-Brooding Lake Tanganyika Cichlid Neolamprologus brevis

    Directory of Open Access Journals (Sweden)

    Kazutaka Ota

    2012-01-01

    Full Text Available Alternative reproductive tactics (ARTs are found in several Lake Tanganyika shell-brooding cichlids. Field studies were conducted in the Wonzye population to examine reproductive ecology and ARTs in the Lake Tanganyika shell-brooding cichlid Neolamprologus brevis. We discovered that this fish occurred in both rocky- and sandy-bottom habitats, but in rocky habitats, brood-caring females exclusively occurred in shell-patches that another cichlid species created. All N. brevis of both sexes in the patches were sexually mature, whereas immature males and females with unripe eggs were found frequently in sandy-bottom habitats. Males in sandy-bottom habitats were smaller, but fed more frequently and were in better somatic condition than males in the patches. Similar tendency was found in females. This indicates that N. brevis uses different habitats depending on the stage of its life history, with migration from sandy-bottom habitats to the shell-patches for reproduction. Males in the patches exhibited different behavior patterns: floating above the patches and lying in the patches. The former was larger, more aggressive, and invested less in gonads (relative to body size than the latter. These results accord with those of other shell-brooding Lake Tanganyika cichlids with ARTs, and they therefore suggest the presence of ARTs in N. brevis.

  1. [Feeding habits of cichlid species (Perciformes: Cichlidae) in Caobas lake, Quintana Roo, Mexico].

    Science.gov (United States)

    Valtierra-Vega, M T; Schmitter-Soto, J J

    2000-01-01

    Feeding habits of seven cichlid species (Archocentrus octofasciatus, A. spilurus, "Cichlasoma" robertsoni, "C." synspilum, "C." urophthalmus, Petenia splendida, Thorichthys meeki) in Lake Caobas, southern Yucatan Peninsula, were studied. Samples were taken with enclosure and cast nets during the dry and rainy seasons of 1995 (day and night). The environment was characterized by measuring temperature, conductivity and pH. All individuals were below 41 mm SL (N = 281). Frequency of occurrence and prey abundance were analyzed. Main prey items were chironomids, mites, copepods, cladocerans, and ostracods. The cichlids fed mainly on zooplankton, with the partial exceptions of P. splendida (piscivore), "C." synspilum and A. spilurus (herbivores). A cluster analysis showed that the most similar trophic spectra were those of T. meeki, "C." robertsoni and "C." salvini, which were also the least diverse. "C." synspilum and A. spilurus had an intermediate distance between their diets and those of other species. The species with the most distinctive feeding composition were P. splendida (with the most diverse and equitable diet) and the omnivore A. octofasciatus (whose diet was the richest one). T. meeki showed quantitative diel, ontogenetic, and seasonal diet changes, but none between sexes. "C." robertsoni, "C." salvini and "C." synspilum differ in food habits in Caobas and in other localities, a fact that underscores the trophic adaptability of cichlids. Trophic overlap between cichlids in Caobas could imply absence of competition, perhaps because resources are abundant in the ecosystem.

  2. The fishes of the cichlid genus Crenicichla in French Guiana (Pisces, Perciformes, Cichlidae)

    NARCIS (Netherlands)

    Ploeg, A.

    1986-01-01

    A review of the species of the cichlid genus Crenicichla Heckel, 1840 in French Guiana is presented. Five species are encountered, viz.: C. saxatilis (Linnaeus, 1758), C. albopunctata Pellegrin, 1904, C. multispinosa Pellegrin, 1903, C. ternetzi Norman, 1926, and C. johanna Heckel, 1840. Their

  3. The role of physiology in the divergence of two incipient cichlid species

    NARCIS (Netherlands)

    Dijkstra, P.D.; Wiegertjes, G.F.; Forlenza, M.; Sluijs, van der I.; Hofmann, H.A.; Metcalfe, N.B.; Groothuis, T.G.

    2011-01-01

    Sexual selection on male coloration has been implicated in the evolution of colourful species flocks of East African cichlid fish. During adaptive radiations, animals diverge in multiple phenotypic traits, but the role of physiology has received limited attention. Here, we report how divergence in

  4. The Diet of Five Cichlid Fish Species from Lake Kariba, Zimbabwe ...

    African Journals Online (AJOL)

    The diet of five cichlid fish species from the littoral areas of Lake Kariba was investigated in 1996-97. Serranochromis macrocephalus, Pseudocrenilabrus philander and Pharyngochromis acuticeps fed mostly on calanoid copepods, chironomid larvae, rotifers, phytoplankton and fish fry. Oreochromis niloticus and 0.

  5. Determination of the Genetic Architecture Underlying Short Wavelength Sensitivity in Lake Malawi Cichlids.

    Science.gov (United States)

    Nandamuri, Sri Pratima; Dalton, Brian E; Carleton, Karen L

    2017-06-01

    African cichlids are an exemplary system to study organismal diversity and rapid speciation. Species differ in external morphology including jaw shape and body coloration, but also differ in sensory systems including vision. All cichlids have 7 cone opsin genes with species differing broadly in which opsins are expressed. The differential opsin expression results in closely related species with substantial differences in spectral sensitivity of their photoreceptors. In this work, we take a first step in determining the genetic basis of opsin expression in cichlids. Using a second generation cross between 2 species with different opsin expression patterns, we make a conservative estimate that short wavelength opsin expression is regulated by a few loci. Genetic mapping in 96 F2 hybrids provides clear evidence of a cis-regulatory region for SWS1 opsin that explains 34% of the variation in expression between the 2 species. Additionally, in situ hybridization has shown that SWS1 and SWS2B opsins are coexpressed in individual single cones in the retinas of F2 progeny. Results from this work will contribute to a better understanding of the genetic architecture underlying opsin expression. This knowledge will help answer long-standing questions about the evolutionary processes fundamental to opsin expression variation and how this contributes to adaptive cichlid divergence. © The American Genetic Association 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Age And Growth Of An Ecotype Cichlid “Wesafu” In Epe Lagoon ...

    African Journals Online (AJOL)

    This explain why only 5 of the 150 specimens were of the age 4+, representing only 3.33% of total specimens which raises serious conservation question and the need for domestication and aquaculture of this highly valued fish in Lagos, Nigeria. Keywords: Age and Growth, Ecotype Cichlid, Epe-Lagoon, Nigeria

  7. Body size diversity and frequency distributions of Neotropical cichlid fishes (Cichliformes: Cichlidae: Cichlinae.

    Directory of Open Access Journals (Sweden)

    Sarah E Steele

    Full Text Available Body size is an important correlate of life history, ecology and distribution of species. Despite this, very little is known about body size evolution in fishes, particularly freshwater fishes of the Neotropics where species and body size diversity are relatively high. Phylogenetic history and body size data were used to explore body size frequency distributions in Neotropical cichlids, a broadly distributed and ecologically diverse group of fishes that is highly representative of body size diversity in Neotropical freshwater fishes. We test for divergence, phylogenetic autocorrelation and among-clade partitioning of body size space. Neotropical cichlids show low phylogenetic autocorrelation and divergence within and among taxonomic levels. Three distinct regions of body size space were identified from body size frequency distributions at various taxonomic levels corresponding to subclades of the most diverse tribe, Geophagini. These regions suggest that lineages may be evolving towards particular size optima that may be tied to specific ecological roles. The diversification of Geophagini appears to constrain the evolution of body size among other Neotropical cichlid lineages; non-Geophagini clades show lower species-richness in body size regions shared with Geophagini. Neotropical cichlid genera show less divergence and extreme body size than expected within and among tribes. Body size divergence among species may instead be present or linked to ecology at the community assembly scale.

  8. Degradation of Victoria Crater, Meridiani Planum, Mars

    Science.gov (United States)

    Grant, J. A.; Wilson, S. A.; Cohen, B. A.; Golombek, M. P.; Geissler, P. E.; Sullivan, R. J.

    2007-12-01

    Victoria crater (2.05N, 354.51E) is ~750 m in diameter and the largest crater on Mars observed in situ. The Mars Exploration Rover Opportunity traversed NW to SE across a broad annulus dominated by dark sand that at least partially surrounds the crater before navigating the northern crater rim. Rover observations of the crater and ejecta deposits are complemented by images with 26-52 cm/pixel scales from the High Resolution Imaging Science Experiment (HiRISE) on Mars Reconnaissance Orbiter and enable assessment of degradation state. The present depth/diameter ratio for Victoria is 0.1, less than the 0.2 expected for a pristine primary impact structure. Together with the eroded, serrated rim, this implies an originally smaller crater diameter and/or considerable infilling consistent with occurrence of a large dune field and few exposed rocks on the crater floor. The height and width of the raised rim is generally 4-5 m and 150-225 m, respectively, less than the 30 m and 500-600 m, respectively, expected for a pristine 750 m diameter crater. Ejecta thicknesses around the rim were derived using rover-based and HiRISE images and yield consistent estimates averaging ~3 m. The serrated rim plan creates a series of promontories extending up to 50 m into the crater and generally fronted by 30-60 degree slopes that are locally vertical and are separated by bays whose floors typically slope 15-25 degrees. A crater originally on order of 600-650 m in diameter and subsequently enlarged by mass wasting and aeolian erosion may yield a structure resembling Victoria today. The steep expression of the promontories and local outcroppings of rocks in the ejecta blanket points to some ongoing mass wasting, but the relative paucity of associated flanking talus indicates derived blocks of sulfate sandstone are not resistant to saltating sand and are rapidly broken down by the wind or are completely covered/filled in by aeolian drift. At Cape St. Vincent, the promontory appears undercut

  9. Genetic sex determination in Astatotilapia calliptera, a prototype species for the Lake Malawi cichlid radiation

    Science.gov (United States)

    Peterson, Erin N.; Cline, Maggie E.; Moore, Emily C.; Roberts, Natalie B.; Roberts, Reade B.

    2017-06-01

    East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.

  10. The Bands Culture in Victoria, Australia: Live Music Benefits Career Paths, Employment and Community

    Science.gov (United States)

    Watson, Amanda; Forrest, David

    2012-01-01

    This study explores the career paths, employment, business opportunities and community contributions made available through the provision and development of the contemporary performance bands' culture in the State of Victoria. It is framed with the support given to live music performers by Arts Victoria, Small Business Victoria and Music Victoria.…

  11. Accounting for Violence at the Victoria Industrial School

    National Research Council Canada - National Science Library

    Bryan Hogeveen

    2009-01-01

    Boys who were inmates at the Victoria Industrial School (VIS) from its opening in 1887 to its closure in 1934 often suffered extreme, violent, and capricious penalties and encountered calculated psychological manipulation...

  12. Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica

    Science.gov (United States)

    Adams, Byron J.; Wall, Diana H.; Virginia, Ross A.; Broos, Emma; Knox, Matthew A.

    2014-01-01

    Abstract The terrestrial ecosystems of Victoria Land, Antarctica are characteristically simple in terms of biological diversity and ecological functioning. Nematodes are the most commonly encountered and abundant metazoans of Victoria Land soils, yet little is known of their diversity and distribution. Herein we present a summary of the geographic distribution, habitats and ecology of the terrestrial nematodes of Victoria Land from published and unpublished sources. All Victoria Land nematodes are endemic to Antarctica, and many are common and widely distributed at landscape scales. However, at smaller spatial scales, populations can have patchy distributions, with the presence or absence of each species strongly influenced by specific habitat requirements. As the frequency of nematode introductions to Antarctica increases, and soil habitats are altered in response to climate change, our current understanding of the environmental parameters associated with the biogeography of Antarctic nematofauna will be crucial to monitoring and possibly mitigating changes to these unique soil ecosystems. PMID:25061360

  13. A test of genetic association among male nuptial coloration, female mating preference, and male aggression bias within a polymorphic population of cichlid fish

    Directory of Open Access Journals (Sweden)

    Inke van der SLUIJS, Peter D. DIJKSTRA, Charlotte M. LINDEYER et al.

    2013-04-01

    Full Text Available Both inter- and intrasexual selection have been implicated in the origin and maintenance of species-rich taxa with diverse sexual traits. Simultaneous disruptive selection by female mate choice and male-male competition can, in theory, lead to speciation without geographical isolation if both act on the same male trait. Female mate choice can generate discontinuities in gene flow, while male-male competition can generate negative frequency-dependent selection stabilizing the male trait polymorphism. Speciation may be facilitated when mating preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations among female mating preference, male aggression bias and male coloration in the Lake Victoria cichlid Pundamilia. We crossed females from a phenotypically variable population with males from both extreme ends of the phenotype distribution in the same population (blue or red. Male offspring of a red sire were significantly redder than males of a blue sire, indicating that intra-population variation in male coloration is heritable. We tested mating preferences of female offspring and aggression biases of male offspring using binary choice tests. There was no evidence for associations at the family level between female mating preferences and coloration of sires, but dam identity had a significant effect on female mate preference. Sons of the red sire directed significantly more aggression to red than blue males, whereas sons of the blue sire did not show any bias. There was a positive correlation among individuals between male aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the maintenance of color polymorphism [Current Zoology 59 (2: 221-229, 2013].

  14. Victoria Land, Ross Sea, and Ross Ice Shelf, Antarctica

    Science.gov (United States)

    2002-01-01

    On December 19, 2001, MODIS acquired data that produced this image of Antarctica's Victoria Land, Ross Ice Shelf, and the Ross Sea. The coastline that runs up and down along the left side of the image denotes where Victoria Land (left) meets the Ross Ice Shelf (right). The Ross Ice Shelf is the world's largest floating body of ice, approximately the same size as France. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  15. Aggression and dominance in cichlids in resident-intruder tests: the role of environmental enrichment

    Directory of Open Access Journals (Sweden)

    Vincent Nijman

    Full Text Available When establishing dominance residents have a greater likelihood to dominate intruders than vice versa, partially because the resident has more to loose that the intruder has to win. This is known as the prior residency effect. In environmentally rich environments this effect should be stronger than in poor environments. Recently Kadry & Barreto (2010, Neotrop Ichthyol 8: 329-332 tested this in the pearl cichlid Geophagus brasiliensis (17 test pairs and reported that environmental enrichment led to a reduction of aggression. We here present data on four other cichlids (332 test pairs showing a stronger prior residency effect in enriched conditions, and, for two species, an increase in aggression. We discuss possible reasons for the differences between studies, focussing on the relationship between aggression and dominance and sample size effects.

  16. The Role of Alternative Splicing and Differential Gene Expression in Cichlid Adaptive Radiation.

    Science.gov (United States)

    Singh, Pooja; Börger, Christine; More, Heather; Sturmbauer, Christian

    2017-10-01

    Species diverge eco-morphologically through the continuous action of natural selection on functionally important structures, producing alternative adaptive morphologies. In cichlid fishes, the oral and pharyngeal jaws are such key structures. Adaptive variation in jaw morphology contributes to trophic specialization, which is hypothesized to fuel their rapid speciation in the East African Great Lakes. Much is known about the genes involved in cichlid jaw and craniofacial development. However, it is still unclear what salient sources of variation gave rise to trophic-niche specialization, facilitating adaptive radiation. Here, we explore two sources of transcriptional variation that may underlie species-specific disparities in jaw morphology. Using whole transcriptome RNA-sequencing, we analyze differences in gene expression and alternative splicing, at the end of postlarval development, in fully functional jaws of six species of cichlids from the Lake Tanganyika tribe Tropheini. Our data reveal a surprisingly high degree of alternative splicing events compared with gene expression differences among species and trophic types. This suggests that differential trophic adaptation of the jaw apparatus may have been shaped by transcriptional rewiring of splicing as well as gene expression variation during the rapid radiation of the Tropheini. Specifically, genes undergoing splicing across most species were found to be enriched for pharyngeal jaw gene ontology terms. Overall, jaw transcriptional patterns at postlarval developmental stage were highly dynamic and species-specific. In conclusion, this work indicates that shifts in alternative splicing could have played a more important role in cichlid adaptive radiation, and possibly adaptive radiation in general, than currently recognized. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  17. Twelve-Day Reinforcement-Based Memory Retention in African Cichlids (Labidochromis caeruleus)

    OpenAIRE

    Ingraham, Erica; Anderson, Nicole D.; Hurd, Peter L.; Hamilton, Trevor J.

    2016-01-01

    The formation of long-term memories for food sources is essential for the survival of most animals. Long-term memory formation in mammalian species has been demonstrated through a variety of conditioning tasks, however, the nature of long-term memory in fish is less known. In the current study, we explored whether African cichlids (Labidochromis caeruleus) could form memories for food-reinforced stimuli that last for 12 days. During the training sessions, fish were reinforced for approaching ...

  18. Twelve-Day Reinforcement-Based Memory Retention in African cichlids (Labidochromis caeruleus)

    OpenAIRE

    Erica Ingraham; Nicole D Anderson; Peter L Hurd; Trevor James Hamilton; Trevor James Hamilton

    2016-01-01

    The formation of long-term memories for food sources is essential for the survival of most animals. Long-term memory formation in mammalian species has been demonstrated through a variety of conditioning tasks, however, the nature of long-term memory in fish is less known. In the current study, we explored whether African cichlids (Labidochromis caeruleus) could form memories for food-reinforced stimuli that last for 12 days. During the training sessions, fish were reinforced for approaching ...

  19. Social experience in early ontogeny has lasting effects on social skills in cooperatively breeding cichlids

    OpenAIRE

    Arnold Cornelia; Taborsky Barbara

    2010-01-01

    The early social environment can affect the social behaviour of animals throughout life. We tested whether the presence of adults during early development influences the social behaviour of juveniles later on in the cooperatively breeding cichlid Neolamprologus pulcher. In a split brood design we raised half of the broods together with parents and with or without brood care helpers and the other half without adults. During early rearing fry raised with adults showed more aggressive and submis...

  20. Wallaceochromis gen. nov, a new chromidotilapiine cichlid genus (Pisces: Perciformes) from West Africa.

    Science.gov (United States)

    Lamboj, Anton; Trummer, Franziska; Metscher, Brian D

    2016-07-26

    A new genus, Wallaceochromis, is described for the chromidotilapiine cichlids of the Pelvicachromis humilis group. It differs from Pelvicachromis sensu stricto in the number and arrangement of tubular infraorbitals, a straighter and sloping dorsal head profile with a low supraoccipital crest, higher abdominal vertebral counts (14-15 vs. 13-14), and in displaying a pattern of vertical bars on the body in several behavioral situations.

  1. Morphology, molecules, and monogenean parasites: an example of an integrative approach to cichlid biodiversity.

    Directory of Open Access Journals (Sweden)

    Maarten Van Steenberge

    Full Text Available The unparalleled biodiversity of Lake Tanganyika (Africa has fascinated biologists for over a century; its unique cichlid communities are a preferred model for evolutionary research. Although species delineation is, in most cases, relatively straightforward, higher-order classifications were shown not to agree with monophyletic groups. Here, traditional morphological methods meet their limitations. A typical example are the tropheine cichlids currently belonging to Simochromis and Pseudosimochromis. The affiliations of these widespread and abundant cichlids are poorly understood. Molecular work suggested that genus and species boundaries should be revised. Moreover, previous morphological results indicated that intraspecific variation should be considered to delineate species in Lake Tanganyika cichlids. We review the genera Simochromis and Pseudosimochromis using an integrative approach. Besides a morphometric study and a barcoding approach, monogenean Cichlidogyrus (Platyhelminthes: Ancyrocephalidae gill parasites, often highly species-specific, are used as complementary markers. Six new species are described. Cichlidogyrus raeymaekersi sp. nov., C. muterezii sp. nov. and C. banyankimbonai sp. nov. infect S. diagramma. Cichlidogyrus georgesmertensi sp. nov. was found on S. babaulti and S. pleurospilus, C. franswittei sp. nov. on both S. marginatus and P. curvifrons and C. frankwillemsi sp. nov. only on P. curvifrons. As relatedness between Cichlidogyrus species usually reflects relatedness between hosts, we considered Simochromis monotypic because the three Cichlidogyrus species found on S. diagramma belonged to a different morphotype than those found on the other Simochromis. The transfer of S. babaulti, S. marginatus, S. pleurospilus and S. margaretae to Pseudosimochromis was justified by the similarity of their Cichlidogyrus fauna and the intermediate morphology of S. margaretae. Finally parasite data also supported the synonymy between S

  2. Living on the wedge: female control of paternity in a cooperatively polyandrous cichlid

    OpenAIRE

    Kohda, Masanori; Heg, Dik; Makino, Yoshimi; Takeyama, Tomohiro; Shibata, Jun-ya; Watanabe, Katsutoshi; Munehara, Hiroyuki; Hori, Michio; Awata, Satoshi

    2009-01-01

    Theories suggest that, in cooperatively breeding species, female control over paternity and reproductive output may affect male reproductive skew and group stability. Female paternity control may come about through cryptic female choice or female reproductive behaviour, but experimental studies are scarce. Here, we show a new form of female paternity control in a cooperatively polyandrous cichlid fish (Julidochromis transcriptus), in which females prefer wedge-shaped nesting sites. Wedge-shap...

  3. Altering an extended phenotype reduces intraspecific male aggression and can maintain diversity in cichlid fish

    Directory of Open Access Journals (Sweden)

    Isabel Santos Magalhaes

    2013-11-01

    Full Text Available Reduced male aggression towards different phenotypes generating negative frequency-dependent intrasexual selection has been suggested as a mechanism to facilitate the invasion and maintenance of novel phenotypes in a population. To date, the best empirical evidence for the phenomenon has been provided by laboratory studies on cichlid fish with different colour polymorphisms. Here we experimentally tested the hypothesis in a natural population of Lake Malawi cichlid fish, in which males build sand-castles (bowers to attract females during seasonal leks. We predicted that if bower shape plays an important role in male aggressive interactions, aggression among conspecific males should decrease when their bower shape is altered. Accordingly, we allocated randomly chosen bowers in a Nyassachromis cf. microcephalus lek into three treatments: control, manipulated to a different shape, and simulated manipulation. We then measured male behaviours and bower shape before and after these treatments. We found that once bower shape was altered, males were involved in significantly fewer aggressive interactions with conspecific males than before manipulation. Mating success was not affected. Our results support the idea that an extended phenotype, such as bower shape, can be important in maintaining polymorphic populations. Specifically, reduced male conspecific aggression towards males with different extended phenotypes (here, bower shapes may cause negative frequency-dependent selection, allowing the invasion and establishment of a new phenotype (bower builder. This could help our understanding of mechanisms of diversification within populations, and in particular, the overall diversification of bower shapes within Lake Malawi cichlids.

  4. Eggspot number and sexual selection in the cichlid fish Astatotilapia burtoni.

    Directory of Open Access Journals (Sweden)

    Frederico Henning

    Full Text Available Sexual selection on male coloration is one of the main mechanisms proposed to explain the explosive speciation rates in East African cichlid fish. True eggspots are color patterns characteristic of the most species-rich lineage of cichlids, the Haplochromini, and have been suggested to be causally related to the speciation processes. Eggspots are thought to have originated by sensory exploitation and subsequently gained several roles in sexual advertisement. However, for most of these functions the evidence is equivocal. In addition, the genetic architecture of this trait still is largely unknown. We conducted bidirectional selective breeding experiments for eggspot numbers in the model cichlid, Astatotilapia burtoni. After two generations, low lines responded significantly, whereas the high lines did not. Body size was both phenotypically and genotypically correlated with eggspot number and showed correlated response to selection. Males with higher numbers of eggspots were found to sire larger offspring. Despite the potential to act as honest indicators of fitness, the behavioral experiments showed no evidence of a role in either intra- or inter-sexual selection. Visual-based female preference was instead explained by courtship intensity. The evolution of this trait has been interpreted in light of adaptive theories of sexual selection, however the present and published results suggest the influence of non-adaptive factors such as sensory exploitation, environmental constraints and sexual antagonism.

  5. Investigation of Acute Toxicity Diazinon, Deltamethrin, Butachlor and pretilachlor on Zebra Cichlid (Cryptoheros nigrofasciatus

    Directory of Open Access Journals (Sweden)

    Ali Sadeghi

    2014-06-01

    Full Text Available Background: The presence of pesticide due to the huge demand for agricultural purposes is very prevalent in surface waters of Iran. These pesticides could finally accumulate in aquatic ecosystems and have been proved to have toxic effects on aquatic animals. The aim of this study was to assess the acute toxicity of Diazinon, Deltamethrin, Butachlor and Pretilachlor on Zebra Cichlid (Cryptoheros nigrofasciatus. Methods: Fish samples were exposed to different concentrations of Diazinon (60% (0, 2, 4, 8, 16 and 32 ppm, Deltamethrin (2.5% (0, 0.02, 0.04, 0.10, 0.20 and 0.40 ppm, butachlor (60% (0, 2, 4, 8, 16 and 32 ppm and pretilachlor (50% (0, 5, 10, 20, 30 and 40 ppm for 96 h within the 100 L glass aquaria and cumulative mortality of Zebra Cichlid fish was calculated in 24-h interval. Results: The very low LC50 obtained for diazinon (5.06±0.37 ppm, deltamethrin (0.15±0.39 ppm, butachlor (8.93±0.26 ppm and pretilachlor (20.72±0.58 ppm indicated that these are highly toxic chemicals. Conclusion: Our results demonstrate that deltamethrin and pretilachlor had the lowest and highest rate of mortality on the Zebra Cichlid respectively.

  6. Ecological diversification associated with the pharyngeal jaw diversity of Neotropical cichlid fishes.

    Science.gov (United States)

    Burress, Edward D

    2016-01-01

    Innovations can facilitate bursts of diversification by increasing access to novel resources and the attainment of novel functional designs. Pharyngognathy, exhibited by highly diverse groups such as wrasses and cichlid fishes, is hypothesized to increase foraging capacity and efficiency. Here, I test the hypothesis that pharyngeal jaw shape and tooth morphology are adaptive in an ecologically diverse radiation of Neotropical cichlid fishes that spans North, Central and South America. I partitioned species into generalized trophic guilds using published stomach content analyses and quantified shape variation of the lower pharyngeal jaw (LPJ) using geometric morphometrics. Additionally, I tested for convergence in LPJ shape and trophic guild by mapping the phylogeny onto the principal components and testing for shifts towards similar evolutionary regimes. Major LPJ shape variation included the length and orientation (i.e. narrow or wide) of the lateral processes and length of the medial process, which varied based on the proportion of fishes and plants consumed. Pharyngeal tooth number, diversity and the frequency of tooth types were not evenly distributed among trophic guilds. There were seven distinct evolutionary regimes that converged upon four optima. Pharyngeal jaw diversification is associated with the exploitation of novel resources among Neotropical cichlids such that pharyngeal specialization has increased access to otherwise poorly accessible resources, such as resources that are difficult to crush (e.g. hard-shelled organisms) and assimilate (e.g. algae). © 2015 The Author. Journal of Animal Ecology © 2015 British Ecological Society.

  7. The Early (Feminist Essays of Victoria Ocampo

    Directory of Open Access Journals (Sweden)

    Doris Meyer

    1996-01-01

    Full Text Available This study examines the essays written by Ocampo between 1920 and 1934, prior to the time when she publicly voiced her adhesion to feminism and the rights of women in Argentine society. In these works from her Testimonios in which Ocampo struggles to find her voice as a female writer, the maleable essay serves her need to engage in discursive dialogues from the margins of the literary culture of her time. Both as a woman and a member of the oligarchy, she questions cultural assumptions and gender-based binary structures common among the male writers of her time, many of whom she knew personally. Using rhetorical strategies that show the self-reflexive and subversive nature of her writing, Ocampo reads and reinterprets these works from a parenthetical feminist perspective, contesting their intellectual and aesthetic biases. The active agency of the reader as writer in these early essays shows Ocampo's awareness of her own unorthodox subject position—alienated from the conventions of her class, her gender, her national culture and language. Her autobiographical musings and her engagement with literary modernity in the 1920s and 1930s reveal a woman who accepted the liabilities of articulating an autonomous self, both in a European and a Latin American context. The influence of family bonds and patriarchal morality decisively shaped, but did not ultimately control, the way Victoria Ocampo eventually defined herself as a feminist author.

  8. Range expansion of the Mayan cichlid, cichlasoma urophthalmus (pisces, cichlidae), above 28°N in Florida

    Science.gov (United States)

    Paperno, R.; Ruiz-Carus, R.; Krebs, J.M.; McIvor, C.C.

    2008-01-01

    Introduced exotic species are a well-recognized problem in Florida's subtropical ecosystems. The presence of the exotic Mayan cichlid (Cichlasoma urophthalmus) was first confirmed in Florida in 1983, when numerous individuals were found in the northeastern Florida Bay. Since then, this species has continued to expand its range northward. The capture, beginning in October 2004 to present, of large numbers of Mayan cichlids from central Florida's east- and west-coast mangrove systems north of 28°N latitude is documented here. Mayan cichlids in a wide range of sizes (estimated ages 0-7 years) at both east- and west-coast sites were collected. In addition, macroscopic examination of gonads showed the presence of developing eggs. The occurrence of multiple age-classes, maturing individuals, cichlid nests, and juveniles, plus repeated collections over a four-year period, indicates that the Mayan cichlid is successfully reproducing and surviving the average winter temperatures in some estuarine waters in central Florida.

  9. Rapid sympatric ecological differentiation of crater lake cichlid fishes within historic times

    Directory of Open Access Journals (Sweden)

    Harrod Chris

    2010-05-01

    Full Text Available Abstract Background After a volcano erupts, a lake may form in the cooled crater and become an isolated aquatic ecosystem. This makes fishes in crater lakes informative for understanding sympatric evolution and ecological diversification in barren environments. From a geological and limnological perspective, such research offers insight about the process of crater lake ecosystem establishment and speciation. In the present study we use genetic and coalescence approaches to infer the colonization history of Midas cichlid fishes (Amphilophus cf. citrinellus that inhabit a very young crater lake in Nicaragua-the ca. 1800 year-old Lake Apoyeque. This lake holds two sympatric, endemic morphs of Midas cichlid: one with large, hypertrophied lips (~20% of the total population and another with thin lips. Here we test the associated ecological, morphological and genetic diversification of these two morphs and their potential to represent incipient speciation. Results Gene coalescence analyses [11 microsatellite loci and mitochondrial DNA (mtDNA sequences] suggest that crater lake Apoyeque was colonized in a single event from the large neighbouring great lake Managua only about 100 years ago. This founding in historic times is also reflected in the extremely low nuclear and mitochondrial genetic diversity in Apoyeque. We found that sympatric adult thin- and thick-lipped fishes occupy distinct ecological trophic niches. Diet, body shape, head width, pharyngeal jaw size and shape and stable isotope values all differ significantly between the two lip-morphs. The eco-morphological features pharyngeal jaw shape, body shape, stomach contents and stable isotopes (δ15N all show a bimodal distribution of traits, which is compatible with the expectations of an initial stage of ecological speciation under disruptive selection. Genetic differentiation between the thin- and thick-lipped population is weak at mtDNA sequence (FST = 0.018 and absent at nuclear

  10. Male-male competition and speciation : aggression bias towards differently coloured rivals varies between stages of speciation in a Lake Victoria cichlid species complex

    NARCIS (Netherlands)

    Dijkstra, P. D.; Seehausen, O.; Pierotti, M. E. R.; Groothuis, T. G. G.

    Sympatric speciation driven by sexual selection by female mate choice on a male trait is a much debated topic. The process is problematic because of the lack of negative frequency-dependent selection that can facilitate the invasion of a novel colour phenotype and stabilize trait polymorphism. It

  11. Community assembly in Lake Tanganyika cichlid fish: quantifying the contributions of both niche-based and neutral processes.

    Science.gov (United States)

    Janzen, Thijs; Alzate, Adriana; Muschick, Moritz; Maan, Martine E; van der Plas, Fons; Etienne, Rampal S

    2017-02-01

    The cichlid family features some of the most spectacular examples of adaptive radiation. Evolutionary studies have highlighted the importance of both trophic adaptation and sexual selection in cichlid speciation. However, it is poorly understood what processes drive the composition and diversity of local cichlid species assemblages on relatively short, ecological timescales. Here, we investigate the relative importance of niche-based and neutral processes in determining the composition and diversity of cichlid communities inhabiting various environmental conditions in the littoral zone of Lake Tanganyika, Zambia. We collected data on cichlid abundance, morphometrics, and local environments. We analyzed relationships between mean trait values, community composition, and environmental variation, and used a recently developed modeling technique (STEPCAM) to estimate the contributions of niche-based and neutral processes to community assembly. Contrary to our expectations, our results show that stochastic processes, and not niche-based processes, were responsible for the majority of cichlid community assembly. We also found that the relative importance of niche-based and neutral processes was constant across environments. However, we found significant relationships between environmental variation, community trait means, and community composition. These relationships were caused by niche-based processes, as they disappeared in simulated, purely neutrally assembled communities. Importantly, these results can potentially reconcile seemingly contrasting findings in the literature about the importance of either niche-based or neutral-based processes in community assembly, as we show that significant trait relationships can already be found in nearly (but not completely) neutrally assembled communities; that is, even a small deviation from neutrality can have major effects on community patterns.

  12. An assessement of the ecosystem health of Lake Victoria (East Africa)

    African Journals Online (AJOL)

    An assessement of the ecosystem health of Lake Victoria (East Africa): Current status, trends and impacts to fishery. ... complicated the ecosystem dynamics of Lake Victoria and pose serious uncertainties about its future stability and sustainability of the fisheries resources. Lake Victoria's future sustainability requires ...

  13. Cutting the Gordian knot: Complex signaling in African cichlids is more than multimodal

    Directory of Open Access Journals (Sweden)

    Moira J. VAN STAADEN, Adam R. SMITH

    2011-04-01

    Full Text Available The active transmission of information from sender to receiver is a fundamental component of communication, and is therefore a primary facet in evolutionary models of sexual selection. Research in several systems has underlined the importance of multiple sensory modalities in courtship signals. However, we still tend to think of individuals as having a relatively static signal in consecutive communicative events. While this may be true for certain traits such as body size or coloration, behaviorally modulated signals can quickly violate this assumption. In this work, we explore how intraspecific variation may be an important component of interspecific signal divergence using cichlid fishes from Lake Malawi. Behavioral analyses were made using six species of Malawian cichlids from two divergent genera. While interspecific differences were found between congeners based on species-level analyses of both acoustic and audiovisual signals, intraspecific variation was of a similar magnitude. Specifically, individual fishes were found to possess highly plastic signal repertoires. This finding was ubiquitous across all species and resulted in a great deal of overlap between heterospecific individuals, despite statistically distinct species means. These results demonstrate that some aspects of courtship in Malawian cichlids are more plastic than previously proposed, and that studies must account for signal variability within individuals. We propose here that behavioral variability in signaling is important in determining the communication landscape on which signals are perceived. We review potential complexity deriving from multimodal signaling, discuss the sources for such lability, and suggest ways in which this issue may be approached experimentally [Current Zoology 57 (2: 237–252, 2011].

  14. Integrating cytogenetics and genomics in comparative evolutionary studies of cichlid fish

    Directory of Open Access Journals (Sweden)

    Mazzuchelli Juliana

    2012-09-01

    Full Text Available Abstract Background The availability of a large number of recently sequenced vertebrate genomes opens new avenues to integrate cytogenetics and genomics in comparative and evolutionary studies. Cytogenetic mapping can offer alternative means to identify conserved synteny shared by distinct genomes and also to define genome regions that are still not fine characterized even after wide-ranging nucleotide sequence efforts. An efficient way to perform comparative cytogenetic mapping is based on BAC clones mapping by fluorescence in situ hybridization. In this report, to address the knowledge gap on the genome evolution in cichlid fishes, BAC clones of an Oreochromis niloticus library covering the linkage groups (LG 1, 3, 5, and 7 were mapped onto the chromosomes of 9 African cichlid species. The cytogenetic mapping data were also integrated with BAC-end sequences information of O. niloticus and comparatively analyzed against the genome of other fish species and vertebrates. Results The location of BACs from LG1, 3, 5, and 7 revealed a strong chromosomal conservation among the analyzed cichlid species genomes, which evidenced a synteny of the markers of each LG. Comparative in silico analysis also identified large genomic blocks that were conserved in distantly related fish groups and also in other vertebrates. Conclusions Although it has been suggested that fishes contain plastic genomes with high rates of chromosomal rearrangements and probably low rates of synteny conservation, our results evidence that large syntenic chromosome segments have been maintained conserved during evolution, at least for the considered markers. Additionally, our current cytogenetic mapping efforts integrated with genomic approaches conduct to a new perspective to address important questions involving chromosome evolution in fishes.

  15. Constraint and opportunity: the genetic basis and evolution of modularity in the cichlid mandible.

    Science.gov (United States)

    Parsons, Kevin J; Márquez, Eladio; Albertson, R Craig

    2012-01-01

    Modular variation, whereby the relative degree of connectivity varies within a system, is thought to evolve through a process of selection that favors the integration of certain traits and the decoupling of others. In this way, modularity may facilitate the pace of evolution and determine evolvability. Alternatively, conserved patterns of modularity may act to constrain the rate and direction of evolution by preventing certain functions from evolving. A comprehensive understanding of the potential interplay between these phenomena will require knowledge of the inheritance and the genetic basis of modularity. Here we explore these ideas in the cichlid mandible by investigating patterns of modularity at the clade and species levels and through the introduction of a new approach, the individual level. Specifically, we assessed patterns of covariation in Lake Malawi cichlid species that employ alternate "biting" and "suction-feeding" modes of feeding and in a hybrid cross between these two ecotypes. Across the suction-feeding clade, patterns of modularity were largely conserved and reflected a functionally based pattern. In contrast, the biting species displayed a pattern of modularity that more closely matched developmental modules. The pattern of modularity present in our F2 population was very similar to the pattern exhibited by the biter, suggesting a role for dominant inheritance. We demonstrate that our individual-level metric of modularity (IMM) is a valid quantitative trait that has a nonlinear relationship with shape. IMMs for each model were used as quantitative characters to map quantitative trait loci (QTL) that underlie modularity. Our QTL analysis offers new insights into the genetic basis of modularity in these fishes that may eventually lead to the discovery of the genetic processes that delineate particular modules. In all, our findings suggest that modularity is both a constraining and an evolvable force in cichlid evolution, as distinct patterns

  16. Histochemical localisation of carbonic anhydrase in the inner ear of developing cichlid fish, Oreochromis mossambicus

    Science.gov (United States)

    Beier, M.; Hilbig, R.; Anken, R.

    2008-12-01

    Inner ear otolith growth in terms of mineralisation mainly depends on the enzyme carbonic anhydrase (CAH). CAH is located in specialised, mitochondria-rich macular cells (ionocytes), which are involved in the endolymphatic ion exchange, and the enzyme is responsible for the provision of the pH-value necessary for otolithic calcium carbonate deposition. In the present study, for the first time the localisation of histochemically demonstrated CAH was analysed during the early larval development of a teleost, the cichlid fish Oreochromis mossambicus. CAH-reactivity was observed already in stage 7 animals (onset of otocyst development; staging follows Anken et al. [Anken, R., Kappel, T., Slenzka, K., Rahmann, H. The early morphogenetic development of the cichlid fish, Oreochromis mossambicus (Perciformes, Teleostei). Zool. Anz. 231, 1-10, 1993]). Neuroblasts (from which sensory and supporting cells are derived) proved to be CAH-positive. Already at stage 12 (hatch), CAH-positive regions could be attributed to ionocyte containing regions both in the so-called meshwork and patches area of the macula (i.e., clearly before ionocytes can be identified on ultrastructural level or by employing immunocytochemistry). In contrast to the circumstances observed in mammalian species, sensory hair cells stained negative for CAH in the cichlid. With the onset of stage 16 (finray primordia in dorsal fin, yolk-sac being increasingly absorbed), CAH-reactivity was observed in the vestibular nerve. This indicates the onset of myelinisation and thus commencement of operation. The localisation of CAH in the inner ear of fish (especially the differences in comparison to mammals) is discussed on the basis of its role in otolith calcification. Since the vestibular system is a detector of acceleration and thus gravity, also aspects regarding effects of altered gravity on CAH and hence on the mineralisation of otoliths in an adaptive process are addressed.

  17. A comparative study of an innate immune response in Lamprologine cichlid fishes

    Science.gov (United States)

    O'Connor, Constance M.; Reddon, Adam R.; Marsh-Rollo, Susan E.; Hellmann, Jennifer K.; Ligocki, Isaac Y.; Hamilton, Ian M.; Balshine, Sigal

    2014-10-01

    Social interactions facilitate pathogen transmission and increase virulence. Therefore, species that live in social groups are predicted to suffer a higher pathogen burden, to invest more heavily in immune defence against pathogens, or both. However, there are few empirical tests of whether social species indeed invest more heavily in immune defence than non-social species. In the current study, we conducted a phylogenetically controlled comparison of innate immune response in Lamprologine cichlid fishes. We focused on three species of highly social cichlids that live in permanent groups and exhibit cooperative breeding ( Julidochromis ornatus, Neolamprologus pulcher and Neolamprologus savoryi) and three species of non-social cichlids that exhibit neither grouping nor cooperative behaviour ( Telmatochromis temporalis, Neolamprologus tetracanthus and Neolamprologus modestus). We quantified the innate immune response by injecting wild fishes with phytohaemagglutinin (PHA), a lectin that causes a cell-mediated immune response. We predicted that the three highly social species would show a greater immune reaction to the PHA treatment, indicating higher investment in immune defence against parasites relative to the three non-social species. We found significant species-level variation in immune response, but contrary to our prediction, this variation did not correspond to social system. However, we found that immune response was correlated with territory size across the six species. Our results indicate that the common assumption of a positive relationship between social system and investment in immune function may be overly simplistic. We suggest that factors such as rates of both in-group and out-group social interactions are likely to be important mediators of the relationship between sociality and immune function.

  18. Assortative mating among Lake Malawi cichlid fish populations is not simply predictable from male nuptial colour

    Directory of Open Access Journals (Sweden)

    Taylor Martin I

    2009-03-01

    Full Text Available Abstract Background Research on the evolution of reproductive isolation in African cichlid fishes has largely focussed on the role of male colours and female mate choice. Here, we tested predictions from the hypothesis that allopatric divergence in male colour is associated with corresponding divergence in preference. Methods We studied four populations of the Lake Malawi Pseudotropheus zebra complex. We predicted that more distantly-related populations that independently evolved similar colours would interbreed freely while more closely-related populations with different colours mate assortatively. We used microsatellite genotypes or mesh false-floors to assign paternity. Fisher's exact tests as well as Binomial and Wilcoxon tests were used to detect if mating departed from random expectations. Results Surprisingly, laboratory mate choice experiments revealed significant assortative mating not only between population pairs with differently coloured males, but between population pairs with similarly-coloured males too. This suggested that assortative mating could be based on non-visual cues, so we further examined the sensory basis of assortative mating between two populations with different male colour. Conducting trials under monochromatic (orange light, intended to mask the distinctive male dorsal fin hues (blue v orange of these populations, did not significantly affect the assortative mating by female P. emmiltos observed under control conditions. By contrast, assortative mating broke down when direct contact between female and male was prevented. Conclusion We suggest that non-visual cues, such as olfactory signals, may play an important role in mate choice and behavioural isolation in these and perhaps other African cichlid fish. Future speciation models aimed at explaining African cichlid radiations may therefore consider incorporating such mating cues in mate choice scenarios.

  19. The reproductive biology of a Central American cichlid Neetroplus nematopus in Lake Xiloá, Nicaragua

    Directory of Open Access Journals (Sweden)

    Kenneth R. McKAYE, Jeremy HALE, Eric P. van den BERGHE

    2010-02-01

    Full Text Available This study was conducted to provide a five-year database on the breeding seasonality and breeding biology of a Central American cichlid fish Neetroplus nematopus, a biparental substratum–spawning cichlid that cares for its eggs, wrigglers, and fry for up to six weeks. A total of 503 breeding pairs were monitored for breeding success. Breeding pairs of N. nematopus are sexually dimorphic in size, with females averaging 39% of male body mass. Fry emerged from 85% of nesting cavities. After three weeks, only 30% of the broods were present in the nesting cavity; these broods had a 30% survival rate, giving a 9% overall survival rate. Nineteen percent of the successful parents with three–week–old broods adopted foreign fry. A consistent unimodal breeding peak in December was observed for five years. This breeding peak differed dramatically from the bimodal breeding season 20 years found in the 1970s. The effects of extensive grenade fishing practices during the 1980s might have played a substantial role in the observed change. Grenade fishing stopped in 1991, and the number of N. nematopus pairs increased by 136% from 1990 to 1995. With increased density of breeding fish, the breeding season for this species also expanded. The balance between divergent selection due to competition for breeding sites and stabilizing selection due to predation pressure on offspring is likely to mold the breeding season for N. nematopus and other cichlids of Lake Xiloá. We suggest that brood adoption and synchrony of breeding is a strategy to reduce predation on the parent's own young [Current Zoology 56 (1: 43–51 2010].

  20. Brain structure evolution in a basal vertebrate clade: evidence from phylogenetic comparative analysis of cichlid fishes

    Directory of Open Access Journals (Sweden)

    Kolm Niclas

    2009-09-01

    Full Text Available Abstract Background The vertebrate brain is composed of several interconnected, functionally distinct structures and much debate has surrounded the basic question of how these structures evolve. On the one hand, according to the 'mosaic evolution hypothesis', because of the elevated metabolic cost of brain tissue, selection is expected to target specific structures mediating the cognitive abilities which are being favored. On the other hand, the 'concerted evolution hypothesis' argues that developmental constraints limit such mosaic evolution and instead the size of the entire brain varies in response to selection on any of its constituent parts. To date, analyses of these hypotheses of brain evolution have been limited to mammals and birds; excluding Actinopterygii, the basal and most diverse class of vertebrates. Using a combination of recently developed phylogenetic multivariate allometry analyses and comparative methods that can identify distinct rates of evolution, even in highly correlated traits, we studied brain structure evolution in a highly variable clade of ray-finned fishes; the Tanganyikan cichlids. Results Total brain size explained 86% of the variance in brain structure volume in cichlids, a lower proportion than what has previously been reported for mammals. Brain structures showed variation in pair-wise allometry suggesting some degree of independence in evolutionary changes in size. This result is supported by variation among structures on the strength of their loadings on the principal size axis of the allometric analysis. The rate of evolution analyses generally supported the results of the multivariate allometry analyses, showing variation among several structures in their evolutionary patterns. The olfactory bulbs and hypothalamus were found to evolve faster than other structures while the dorsal medulla presented the slowest evolutionary rate. Conclusion Our results favor a mosaic model of brain evolution, as certain

  1. Contravention of town planning regulations in Ikoyi and Victoria ...

    African Journals Online (AJOL)

    The study investigated possible relationships between educational attainment, awareness of town planning regulations and contravening these regulations in Ikoyi and Victoria Island, Lagos. Both primary and secondary data were used for the study. Secondary data were obtained from both published and unpublished ...

  2. 3D DIGITAL CADASTRE JOURNEY IN VICTORIA, AUSTRALIA

    Directory of Open Access Journals (Sweden)

    D. Shojaei

    2017-10-01

    Full Text Available Land development processes today have an increasing demand to access three-dimensional (3D spatial information. Complex land development may need to have a 3D model and require some functions which are only possible using 3D data. Accordingly, the Intergovernmental Committee on Surveying and Mapping (ICSM, as a national body in Australia provides leadership, coordination and standards for surveying, mapping and national datasets has developed the Cadastre 2034 strategy in 2014. This strategy has a vision to develop a cadastral system that enables people to readily and confidently identify the location and extent of all rights, restrictions and responsibilities related to land and real property. In 2014, the land authority in the state of Victoria, Australia, namely Land Use Victoria (LUV, has entered the challenging area of designing and implementing a 3D digital cadastre focused on providing more efficient and effective services to the land and property industry. LUV has been following the ICSM 2034 strategy which requires developing various policies, standards, infrastructures, and tools. Over the past three years, LUV has mainly focused on investigating the technical aspect of a 3D digital cadastre. This paper provides an overview of the 3D digital cadastre investigation progress in Victoria and discusses the challenges that the team faced during this journey. It also addresses the future path to develop an integrated 3D digital cadastre in Victoria.

  3. Research on School-Based Management in Victoria.

    Science.gov (United States)

    Gamage, David T.; And Others

    1996-01-01

    Describes a 1992-93 research project involving 66 state schools that attempted to ascertain the overall effectiveness of school-based management in Victoria, Australia. Findings of the Likert-style survey revealed substantial participant satisfaction with school councils' current composition, information provision, and overall functioning. (20…

  4. Fishing Business Arrangements and Sustainability in Lake Victoria ...

    African Journals Online (AJOL)

    In this article an attempt is made to analyse the existing production relations between the owners of the vessels and the crewmembers and the concern for sustainability. Our results found that the existing sharing system in Lake Victoria poses a big challenge in as far as sustainability is concerned. Some of the system such ...

  5. Implementing Co-management of Lake Victoria's Fisheries ...

    African Journals Online (AJOL)

    There are still many challenges facing the sustainable management of Lake Victoria fisheries, including; lack of compliance with regulations and rapid increase in fishing effort, environmental degradation, inadequate service provision and the high prevalence of HIV/AIDS amongst the fishing communities. Key words: Lake ...

  6. The Lake Victoria Intense Storm Early Warning System (VIEWS)

    Science.gov (United States)

    Thiery, Wim; Gudmundsson, Lukas; Bedka, Kristopher; Semazzi, Fredrick; Lhermitte, Stef; Willems, Patrick; van Lipzig, Nicole; Seneviratne, Sonia I.

    2017-04-01

    Weather extremes have harmful impacts on communities around Lake Victoria in East Africa. Every year, intense nighttime thunderstorms cause numerous boating accidents on the lake, resulting in thousands of deaths among fishermen. Operational storm warning systems are therefore crucial. Here we complement ongoing early warning efforts based on NWP, by presenting a new satellite data-driven storm prediction system, the prototype Lake Victoria Intense storm Early Warning System (VIEWS). VIEWS derives predictability from the correlation between afternoon land storm activity and nighttime storm intensity on Lake Victoria, and relies on logistic regression techniques to forecast extreme thunderstorms from satellite observations. Evaluation of the statistical model reveals that predictive power is high and independent of the input dataset. We then optimise the configuration and show that also false alarms contain valuable information. Our results suggest that regression-based models that are motivated through process understanding have the potential to reduce the vulnerability of local fishing communities around Lake Victoria. The experimental prediction system is publicly available under the MIT licence at http://github.com/wthiery/VIEWS.

  7. Study of genetic variation in population of Bipolaris victoriae , the ...

    African Journals Online (AJOL)

    Isolates of Bipolaris victoriae were analysed by random amplified polymorphic DNA (RAPD) techniques to determine the amount of intraspecific genetic variability. Seven primers were applied and DNA bands of 200-5000 bp were produced. Cluster analysis using UPGMA method gave five groups. Levels of polymorphism ...

  8. satellite lakes of lake victoria basin (tanzanian side)

    African Journals Online (AJOL)

    Studies on phytoplankton species diversity and abundance were carried out in 8 selected satellite lakes within the Lake Victoria ... cyanobacteria occurrence and their unforeseen effects such as toxin production and oxygen depletion during nights that may ..... Species extinction and concomitant ecological changes in Lake.

  9. Governance and Welfare of Fishing Communities of Lake Victoria ...

    African Journals Online (AJOL)

    ... have potable water or electricity. Educational standards remain low and many communities lack proper sanitation, and are therefore at risk of disease, while most basic facilities such as hospitals, schools and clinics are not within their reach. Key Words; Co-management, Beach Management Units, Lake Victoria, Health, ...

  10. Total mercury concentration in common fish species of Lake Victoria ...

    African Journals Online (AJOL)

    Total mercury (THg) concentration was analysed in muscles of common fish species of Lake Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption Spectrophotometric technique. Mercury concentration in all fish species was generally lower than the WHO maximum allowable ...

  11. Transactional sex in the fishing communities along Lake Victoria ...

    African Journals Online (AJOL)

    The study describes the nature, context and implications of a unique form of transactional sexual relationships in the fishing communities along Lake Victoria in Kisumu County, Kenya. We conducted 12 focus group discussions and 17 key informant interviews among fishermen, fishmongers and fish transporters in Kisumu.

  12. Domestication of medicinal tree species in the Victoria lakeshore ...

    African Journals Online (AJOL)

    Mo

    Therefore, there is high potential of marketing forest products by the subsistence farmers. Growing medicinal plants is one great opportunity for raising household incomes in this area. A survey was conducted among herbalists living around the Victoria lakeshore region. Questionnaires were administered through formal ...

  13. Catalogue Use at the State Library of Victoria

    Science.gov (United States)

    Hider, Philip

    2008-01-01

    A questionnaire survey conducted at the State Library of Victoria indicates that users in general, and not just scholars, value the standard elements of bibliographic data found in the Library's catalogues, and consider all these elements useful for finding, identifying and selecting items. Rather than making do with less, users wanted more…

  14. Vocabulary Size Research at Victoria University of Wellington, New Zealand

    Science.gov (United States)

    Nation, Paul; Coxhead, Averil

    2014-01-01

    The English Language Institute (now the School of Linguistics and Applied Language Studies) at Victoria University of Wellington has a long history of corpus-based vocabulary research, especially after the arrival of the second director of the institute, H. V. George, and the appointment of Helen Barnard, whom George knew in India. George's…

  15. SEDIMENTS FROM SOUTHERN LAKE VICTORIA AND ITS BASIN

    African Journals Online (AJOL)

    Water, sediment and soil samples collected from Southern Lake Victoria and its basin were analysed for 76 organochlorine, organophosphorous, carbamate and pyrethroid pesticide residues. The samples were collected from sampling stations in nine districts on the Tanzanian side of the lake, namely Mwanza, Sengerema ...

  16. Early warnings of hazardous thunderstorms over Lake Victoria

    NARCIS (Netherlands)

    Thiery, Wim; Gudmundsson, Lukas; Bedka, Kristopher; Semazzi, Fredrick H.M.; Lhermitte, S.L.M.; Willems, Patrick; van Lipzig, Nicole P. M.; Seneviratne, Sonia I.

    2017-01-01

    Weather extremes have harmful impacts on communities around Lake Victoria in East Africa. Every year, intense nighttime thunderstorms cause numerous boating accidents on the lake, resulting in thousands of deaths among fishermen. Operational storm warning systems are therefore crucial. Here we

  17. Lake Victoria's Water Budget and the Potential Effects of Climate ...

    African Journals Online (AJOL)

    This paper presents the Lake Victoria water budget for the period 1950-2004 and findings of a study on potential climate change impact on the lake's Hydrology through the 21st Century. The mass balance components are computed from measured and simulated data. A2 and B2 emission scenarios of the Special Report ...

  18. Early warnings of hazardous thunderstorms over Lake Victoria

    Science.gov (United States)

    Thiery, Wim; Gudmundsson, Lukas; Bedka, Kristopher; Semazzi, Fredrick H. M.; Lhermitte, Stef; Willems, Patrick; van Lipzig, Nicole P. M.; Seneviratne, Sonia I.

    2017-07-01

    Weather extremes have harmful impacts on communities around Lake Victoria in East Africa. Every year, intense nighttime thunderstorms cause numerous boating accidents on the lake, resulting in thousands of deaths among fishermen. Operational storm warning systems are therefore crucial. Here we complement ongoing early warning efforts based on numerical weather prediction, by presenting a new satellite data-driven storm prediction system, the prototype Lake Victoria Intense storm Early Warning System (VIEWS). VIEWS derives predictability from the correlation between afternoon land storm activity and nighttime storm intensity on Lake Victoria, and relies on logistic regression techniques to forecast extreme thunderstorms from satellite observations. Evaluation of the statistical model reveals that predictive power is high and independent of the type of input dataset. We then optimise the configuration and show that false alarms also contain valuable information. Our results suggest that regression-based models that are motivated through process understanding have the potential to reduce the vulnerability of local fishing communities around Lake Victoria. The experimental prediction system is publicly available under the MIT licence at http://github.com/wthiery/VIEWS.

  19. Climate Change and Fishery Sustainability in Lake Victoria ...

    African Journals Online (AJOL)

    The fisheries of Lake Victoria have recently undergone rapid ecological and social change. Loss of diversity in terms of species richness and economic opportunity has increased the system's vulnerability to additional economic, ecological, and social stressors predicted with future climate change. This paper discusses the ...

  20. Salinity effects on behavioural response to hypoxia in the non-native Mayan cichlid Cichlasoma urophthalmus from Florida Everglades wetlands.

    Science.gov (United States)

    Schofield, P J; Loftus, W F; Fontaine, J A

    2009-04-01

    This study quantified the hypoxia tolerance of the Mayan cichlid Cichlasoma urophthalmus over a range of salinities. The species was very tolerant of hypoxia, using aquatic surface respiration (ASR) and buccal bubble holding when oxygen tensions dropped to Everglades, however, aggression levels for C. uropthalmus were markedly higher.

  1. Genetic isolation and morphological divergence mediated by high-energy rapids in two cichlid genera from the lower Congo rapids

    Directory of Open Access Journals (Sweden)

    Stiassny Melanie LJ

    2010-05-01

    Full Text Available Abstract Background It is hypothesized that one of the mechanisms promoting diversification in cichlid fishes in the African Great Lakes has been the well-documented pattern of philopatry along shoreline habitats leading to high levels of genetic isolation among populations. However lake habitats are not the only centers of cichlid biodiversity - certain African rivers also contain large numbers of narrowly endemic species. Patterns of isolation and divergence in these systems have tended to be overlooked and are not well understood. Results We examined genetic and morphological divergence among populations of two narrowly endemic cichlid species, Teleogramma depressum and Lamprologus tigripictilis, from a 100 km stretch of the lower Congo River using both nDNA microsatellites and mtDNA markers along with coordinate-based morphological techniques. In L. tigripictilis, the strongest genetic break was concordant with measurable phenotypic divergence but no morphological disjunction was detected for T. depressum despite significant differentiation at mtDNA and nDNA microsatellite markers. Conclusions The genetic markers revealed patterns of philopatry and estimates of genetic isolation that are among the highest reported for any African cichlid species over a comparable geographic scale. We hypothesize that the high levels of philopatry observed are generated and maintained by the extreme hydrology of the lower Congo River.

  2. Review of the cichlid genus Crenicichla Heckel, 1840 from Surinam, with descriptions of three new species (Pisces, Perciformes, Cichlidae)

    NARCIS (Netherlands)

    Ploeg, A.

    1987-01-01

    The Surinam representatives of the cichlid genus Crenicichla Heckel, 1840 are reviewed. Seven species, among which three new to science, have been found, viz.: C. albopunctata Pellegrin, 1904, C. coppenamensis sp. n., C. nickeriensis sp. n., C. saxatilis (L., 1758), C. sipaliwini sp. n., C. lugubris

  3. Lateralized kinematics of predation behavior in a Lake Tanganyika scale-eating cichlid fish.

    Directory of Open Access Journals (Sweden)

    Yuichi Takeuchi

    Full Text Available Behavioral lateralization has been documented in many vertebrates. The scale-eating cichlid fish Perissodus microlepis is well known for exhibiting lateral dimorphism in its mouth morphology and lateralized behavior in robbing scales from prey fish. A previous field study indicated that this mouth asymmetry closely correlates with the side on which prey is attacked, but details of this species' predation behavior have not been previously analyzed because of the rapidity of the movements. Here, we studied scale-eating behavior in cichlids in a tank through high-speed video monitoring and quantitative assessment of behavioral laterality and kinematics. The fish observed showed a clear bias toward striking on one side, which closely correlated with their asymmetric mouth morphologies. Furthermore, the maximum angular velocity and amplitude of body flexion were significantly larger during attacks on the preferred side compared to those on the nonpreferred side, permitting increased predation success. In contrast, no such lateral difference in movement elements was observed in acoustically evoked flexion during the escape response, which is similar to flexion during scale eating and suggests that they share a common motor control pathway. Thus the neuronal circuits controlling body flexion during scale eating may be functionally lateralized upstream of this common motor pathway.

  4. Molecular investigation of genetic assimilation during the rapid adaptive radiations of East African cichlid fishes.

    Science.gov (United States)

    Gunter, Helen M; Schneider, Ralf F; Karner, Immanuel; Sturmbauer, Christian; Meyer, Axel

    2017-12-01

    Adaptive radiations are characterized by adaptive diversification intertwined with rapid speciation within a lineage resulting in many ecologically specialized, phenotypically diverse species. It has been proposed that adaptive radiations can originate from ancestral lineages with pronounced phenotypic plasticity in adaptive traits, facilitating ecologically driven phenotypic diversification that is ultimately fixed through genetic assimilation of gene regulatory regions. This study aimed to investigate how phenotypic plasticity is reflected in gene expression patterns in the trophic apparatus of several lineages of East African cichlid fishes, and whether the observed patterns support genetic assimilation. This investigation used a split brood experimental design to compare adaptive plasticity in species from within and outside of adaptive radiations. The plastic response was induced in the crushing pharyngeal jaws through feeding individuals either a hard or soft diet. We find that nonradiating, basal lineages show higher levels of adaptive morphological plasticity than the derived, radiated lineages, suggesting that these differences have become partially genetically fixed during the formation of the adaptive radiations. Two candidate genes that may have undergone genetic assimilation, gif and alas1, were identified, in addition to alterations in the wiring of LPJ patterning networks. Taken together, our results suggest that genetic assimilation may have dampened the inducibility of plasticity related genes during the adaptive radiations of East African cichlids, flattening the reaction norms and canalizing their feeding phenotypes, driving adaptation to progressively more narrow ecological niches. © 2017 John Wiley & Sons Ltd.

  5. Twelve-Day Reinforcement-Based Memory Retention in African Cichlids (Labidochromis caeruleus)

    Science.gov (United States)

    Ingraham, Erica; Anderson, Nicole D.; Hurd, Peter L.; Hamilton, Trevor J.

    2016-01-01

    The formation of long-term memories for food sources is essential for the survival of most animals. Long-term memory formation in mammalian species has been demonstrated through a variety of conditioning tasks, however, the nature of long-term memory in fish is less known. In the current study, we explored whether African cichlids (Labidochromis caeruleus) could form memories for food-reinforced stimuli that last for 12 days. During the training sessions, fish were reinforced for approaching an upward drifting line grating. After a rest period of 12 days, fish demonstrated a significant preference for the upward drifting grating. To determine whether this preference could also be reversed, fish were then reinforced for approaching a downward drifting line grating after a 20-day rest period. When tested 12 days later, there were no significant differences in preference for either stimulus; however, following a second training period for the downward stimulus, there was a significant preference for the downward drifting grating. This suggests that cichlids are able to form reversible discrimination-based memories for food-reinforced stimuli that remain consolidated for at least 12 days. PMID:27582695

  6. Evaluating genomic divergence and parallelism in replicate ecomorphs from young and old cichlid adaptive radiations.

    Science.gov (United States)

    McGee, Matthew D; Neches, Russell Y; Seehausen, Ole

    2016-01-01

    Comparative genomic studies of closely related species typically focus on single species pairs at one given stage of divergence. That makes it difficult to infer the continuum of evolutionary process during speciation and beyond. Here, we use whole-genome resequencing to examine genomic patterns of divergence in three sympatric cichlid species pairs with very similar functional and ecological differentiation, but different ages. We find a strong signature of increasing genomic divergence with time in both the mitochondrial genome and the nuclear genome. In contrast to many other systems, we find that in these cichlids, regions of elevated relative differentiation also exhibit increased absolute differentiation. We detect a signature of convergent evolution in a comparison of outlier regions across all three species pair comparisons, but the extent of it is modest, and regions that are strongly divergent in any one pair tend to be only slightly elevated in the other pairs, consistent with a repeatable but polygenic basis of traits that characterize the ecomorphs. Our results suggest that strong functional phenotypic differentiation, as seen in all three species pairs, is generally associated with a clear signature of genomic divergence, even in the youngest species pair. © 2015 John Wiley & Sons Ltd.

  7. The Monogenean Parasite Fauna of Cichlids: A Potential Tool for Host Biogeography

    Science.gov (United States)

    Pariselle, Antoine; Boeger, Walter A.; Snoeks, Jos; Bilong Bilong, Charles F.; Morand, Serge; Vanhove, Maarten P. M.

    2011-01-01

    We discuss geographical distribution and phylogeny of Dactylogyridea (Monogenea) parasitizing Cichlidae to elucidate their hosts' history. Although mesoparasitic Monogenea (Enterogyrus spp.) show typical vicariant distribution, ectoparasitic representatives from different continents are not considered sister taxa, hence their distribution cannot result from vicariance alone. Because of the close host-parasite relationship, this might indicate that present-day cichlid distribution may also reflect dispersal through coastal or brackish waters. Loss of ectoparasites during transoceanic migration, followed by lateral transfer from other fish families might explain extant host-parasite associations. Because of its mesoparasitic nature, hence not subject to salinity variations of the host's environment, Enterogyrus could have survived marine migrations, intolerable for ectoparasites. Host-switches and salinity transitions may be invoked to explain the pattern revealed by a preliminary morphological phylogeny of monogenean genera from Cichlidae and other selected Monogenea genera, rendering the parasite distribution explicable under both vicariance and dispersal. Testable hypotheses are put forward in this parasitological approach to cichlid biogeography. Along with more comprehensive in-depth morphological phylogeny, comparison with molecular data, clarifying dactylogyridean evolution on different continents and from various fish families, and providing temporal information on host-parasite history, are needed to discriminate between the possible scenarios. PMID:21869935

  8. The Monogenean Parasite Fauna of Cichlids: A Potential Tool for Host Biogeography

    Directory of Open Access Journals (Sweden)

    Antoine Pariselle

    2011-01-01

    Full Text Available We discuss geographical distribution and phylogeny of Dactylogyridea (Monogenea parasitizing Cichlidae to elucidate their hosts' history. Although mesoparasitic Monogenea (Enterogyrus spp. show typical vicariant distribution, ectoparasitic representatives from different continents are not considered sister taxa, hence their distribution cannot result from vicariance alone. Because of the close host-parasite relationship, this might indicate that present-day cichlid distribution may also reflect dispersal through coastal or brackish waters. Loss of ectoparasites during transoceanic migration, followed by lateral transfer from other fish families might explain extant host-parasite associations. Because of its mesoparasitic nature, hence not subject to salinity variations of the host's environment, Enterogyrus could have survived marine migrations, intolerable for ectoparasites. Host-switches and salinity transitions may be invoked to explain the pattern revealed by a preliminary morphological phylogeny of monogenean genera from Cichlidae and other selected Monogenea genera, rendering the parasite distribution explicable under both vicariance and dispersal. Testable hypotheses are put forward in this parasitological approach to cichlid biogeography. Along with more comprehensive in-depth morphological phylogeny, comparison with molecular data, clarifying dactylogyridean evolution on different continents and from various fish families, and providing temporal information on host-parasite history, are needed to discriminate between the possible scenarios.

  9. Assessment of Mercury Bioaccumulation in Zebra Cichlid (Cichlasoma Nigrofasciatum Exposed to Sublethal Concentrations of Permethrin

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-12-01

    Full Text Available Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parameters including other pollutants. Therefore, the objectives of this research were to determine the effects of permethrin on bioaccumulation of mercury in zebra cichlid. Methods: Acute toxicity (LC50 of permethrin and mercury chloride was evaluated by estimating mortality in Probit Model in SPSS (version 19.0 IBM. In sub-lethal toxicity, zebra cichlid (Cichlasoma nigrofasciatum was exposed to various concentrations of permethrin (0.0, 0.40, 0.80, 1.20 and 1.60 µg.L-1 combined with 20 µg.L-1 mercury chloride for 15 days. At the end of the experiment, mercury concentrations were measured using ICP-OES-Perkin elmer (optima 7300-DV. Results: 96 h LC50 values of permethrin and mercury for C. nigrofasciatum were calculated to be 17.55 µg.L-1 and 140.38 µg.L-1, respectively. Our results clearly showed that the bioaccumulation of mercury in the specimens increased with increasing concentrations of permethrin to 1.20 and 1.60 µg.L-1. Conclusion: Increasing the concentration of permethrin had synergistic effects on the bioaccumulation of mercury in fish.

  10. Twelve-Day Reinforcement-Based Memory Retention in African cichlids (Labidochromis caeruleus

    Directory of Open Access Journals (Sweden)

    Erica Ingraham

    2016-08-01

    Full Text Available The formation of long-term memories for food sources is essential for the survival of most animals. Long-term memory formation in mammalian species has been demonstrated through a variety of conditioning tasks, however, the nature of long-term memory in fish is less known. In the current study, we explored whether African cichlids (Labidochromis caeruleus could form memories for food-reinforced stimuli that last for 12 days. During the training sessions, fish were reinforced for approaching an upward drifting line grating. After a rest period of 12 days, fish demonstrated a significant preference for the upward drifting grating. To determine whether this preference could also be reversed, fish were then reinforced for approaching a downward drifting line grating after a 20-day rest period. When tested 12 days later, there were no significant differences in preference for either stimulus; however, following a second training period for the downward stimulus, there was a significant preference for the downward drifting grating. This suggests that cichlids are able to form reversible discrimination-based memories for food-reinforced stimuli that remain consolidated for at least 12 days.

  11. Twelve-Day Reinforcement-Based Memory Retention in African Cichlids (Labidochromis caeruleus).

    Science.gov (United States)

    Ingraham, Erica; Anderson, Nicole D; Hurd, Peter L; Hamilton, Trevor J

    2016-01-01

    The formation of long-term memories for food sources is essential for the survival of most animals. Long-term memory formation in mammalian species has been demonstrated through a variety of conditioning tasks, however, the nature of long-term memory in fish is less known. In the current study, we explored whether African cichlids (Labidochromis caeruleus) could form memories for food-reinforced stimuli that last for 12 days. During the training sessions, fish were reinforced for approaching an upward drifting line grating. After a rest period of 12 days, fish demonstrated a significant preference for the upward drifting grating. To determine whether this preference could also be reversed, fish were then reinforced for approaching a downward drifting line grating after a 20-day rest period. When tested 12 days later, there were no significant differences in preference for either stimulus; however, following a second training period for the downward stimulus, there was a significant preference for the downward drifting grating. This suggests that cichlids are able to form reversible discrimination-based memories for food-reinforced stimuli that remain consolidated for at least 12 days.

  12. Color changing and behavioral context in the Amazonian Dwarf Cichlid Apistogramma hippolytae (Perciformes

    Directory of Open Access Journals (Sweden)

    Raoni Rosa Rodrigues

    Full Text Available Animal coloration has many functions, and fishes are noted among vertebrates for presenting a wide variety of color patterns. Although in marine fishes the relationship between body coloration and behavioral context is well documented, there's not much information about freshwater fishes. Here we describe color patterns displayed by the dwarf cichlid Apistogramma hippolytae and suggest that these patterns are dependent on different social and behavioral settings. Field observations were conducted underwater in a pond in Central Amazonia, Brazil. We recorded six body coloration patterns related to seven different kinds of behavioral activities: foraging, resting, reproductive and agonistic displays, aggression (attacking and fleeing and parental care. Changes in coloration occur rapidly and take only a few seconds. Females on parental care exhibited a unique pattern that are more persistent and probably manifests more slowly. In the shallow and clear waters of the natural environment of this dwarf cichlid, color communication seems to constitute an efficient way to display information about individual mood, social status and reproductive readiness, contributing to minimize loss of energy in unnecessary interactions.

  13. Diet-morphology correlations in the radiation of South American geophagine cichlids (Perciformes: Cichlidae: Cichlinae).

    Science.gov (United States)

    López-Fernández, Hernán; Winemiller, Kirk O; Montaña, Carmen; Honeycutt, Rodney L

    2012-01-01

    Genera within the South American cichlid tribe Geophagini display specialized feeding and reproductive strategies, with some taxa specialized for both substrate-sifting and mouth brooding. Several lineages within the clade also possess an epibranchial lobe (EBL), a unique pharyngeal structure that has been proposed to have a function in feeding and/or mouth brooding. A recently published genus-level phylogeny of Neotropical cichlids was used as the evolutionary framework for investigating the evolution of morphological features presumably correlated with diet and mouth brooding in the tribe Geophagini. We tested for possible associations between the geophagine epibranchial lobe and benthic feeding and mouth brooding. We also addressed whether the EBL may be associated with unique patterns of diversification in certain geophagine clades. Tests of binary character correlations revealed the EBL was significantly associated with mouth brooding. We also tested for a relationship between diet and morphology. We analyzed stomach contents and morphometric variation among 21 species, with data for two additional species obtained from the literature. Principal Components Analysis revealed axes of morphological variation significantly correlated with piscivory and benthivory, and both morphology and diet were significantly associated with phylogeny. These results suggest that the EBL could be an adaptation for either feeding or mouth brooding. The EBL, however, was not associated with species richness or accelerated rates of phyletic diversification.

  14. Diet-morphology correlations in the radiation of South American geophagine cichlids (Perciformes: Cichlidae: Cichlinae.

    Directory of Open Access Journals (Sweden)

    Hernán López-Fernández

    Full Text Available Genera within the South American cichlid tribe Geophagini display specialized feeding and reproductive strategies, with some taxa specialized for both substrate-sifting and mouth brooding. Several lineages within the clade also possess an epibranchial lobe (EBL, a unique pharyngeal structure that has been proposed to have a function in feeding and/or mouth brooding. A recently published genus-level phylogeny of Neotropical cichlids was used as the evolutionary framework for investigating the evolution of morphological features presumably correlated with diet and mouth brooding in the tribe Geophagini. We tested for possible associations between the geophagine epibranchial lobe and benthic feeding and mouth brooding. We also addressed whether the EBL may be associated with unique patterns of diversification in certain geophagine clades. Tests of binary character correlations revealed the EBL was significantly associated with mouth brooding. We also tested for a relationship between diet and morphology. We analyzed stomach contents and morphometric variation among 21 species, with data for two additional species obtained from the literature. Principal Components Analysis revealed axes of morphological variation significantly correlated with piscivory and benthivory, and both morphology and diet were significantly associated with phylogeny. These results suggest that the EBL could be an adaptation for either feeding or mouth brooding. The EBL, however, was not associated with species richness or accelerated rates of phyletic diversification.

  15. Rates of phenotypic evolution of ecological characters and sexual traits during the Tanganyikan cichlid adaptive radiation.

    Science.gov (United States)

    Gonzalez-Voyer, A; Kolm, N

    2011-11-01

    Theory suggests that sexual traits evolve faster than ecological characters. However, characteristics of a species niche may also influence evolution of sexual traits. Hence, a pending question is whether ecological characters and sexual traits present similar tempo and mode of evolution during periods of rapid ecological divergence, such as adaptive radiation. Here, we use recently developed phylogenetic comparative methods to analyse the temporal dynamics of evolution for ecological and sexual traits in Tanganyikan cichlids. Our results indicate that whereas disparity in ecological characters was concentrated early in the radiation, disparity in sexual traits remained high throughout the radiation. Thus, closely related Tanganyikan cichlids presented higher disparity in sexual traits than ecological characters. Sexual traits were also under stronger selection than ecological characters. In sum, our results suggest that ecological characters and sexual traits present distinct evolutionary patterns, and that sexual traits can evolve faster than ecological characters, even during adaptive radiation. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

  16. Diet-Morphology Correlations in the Radiation of South American Geophagine Cichlids (Perciformes: Cichlidae: Cichlinae)

    Science.gov (United States)

    López-Fernández, Hernán; Winemiller, Kirk O.; Montaña, Carmen; Honeycutt, Rodney L.

    2012-01-01

    Genera within the South American cichlid tribe Geophagini display specialized feeding and reproductive strategies, with some taxa specialized for both substrate-sifting and mouth brooding. Several lineages within the clade also possess an epibranchial lobe (EBL), a unique pharyngeal structure that has been proposed to have a function in feeding and/or mouth brooding. A recently published genus-level phylogeny of Neotropical cichlids was used as the evolutionary framework for investigating the evolution of morphological features presumably correlated with diet and mouth brooding in the tribe Geophagini. We tested for possible associations between the geophagine epibranchial lobe and benthic feeding and mouth brooding. We also addressed whether the EBL may be associated with unique patterns of diversification in certain geophagine clades. Tests of binary character correlations revealed the EBL was significantly associated with mouth brooding. We also tested for a relationship between diet and morphology. We analyzed stomach contents and morphometric variation among 21 species, with data for two additional species obtained from the literature. Principal Components Analysis revealed axes of morphological variation significantly correlated with piscivory and benthivory, and both morphology and diet were significantly associated with phylogeny. These results suggest that the EBL could be an adaptation for either feeding or mouth brooding. The EBL, however, was not associated with species richness or accelerated rates of phyletic diversification. PMID:22485154

  17. A sensory bias has triggered the evolution of egg-spots in cichlid fishes.

    Directory of Open Access Journals (Sweden)

    Bernd Egger

    Full Text Available Although, generally, the origin of sex-limited traits remains elusive, the sensory exploitation hypothesis provides an explanation for the evolution of male sexual signals. Anal fin egg-spots are such a male sexual signal and a key characteristic of the most species-rich group of cichlid fishes, the haplochromines. Males of about 1500 mouth-brooding species utilize these conspicuous egg-dummies during courtship--apparently to attract females and to maximize fertilization success. Here we test the hypothesis that the evolution of haplochromine egg-spots was triggered by a pre-existing bias for eggs or egg-like coloration. To this end, we performed mate-choice experiments in the basal haplochromine Pseudocrenilabrus multicolor, which manifests the plesiomorphic character-state of an egg-spot-less anal fin. Experiments using computer-animated photographs of males indeed revealed that females prefer images of males with virtual ('in-silico' egg-spots over images showing unaltered males. In addition, we tested for color preferences (outside a mating context in a phylogenetically representative set of East African cichlids. We uncovered a strong preference for yellow, orange or reddish spots in all haplochromines tested and, importantly, also in most other species representing more basal lines. This pre-existing female sensory bias points towards high-quality (carotenoids-enriched food suggesting that it is adaptive.

  18. BioCichlid: central dogma-based 3D visualization system of time-course microarray data on a hierarchical biological network.

    Science.gov (United States)

    Ishiwata, Ryosuke R; Morioka, Masaki S; Ogishima, Soichi; Tanaka, Hiroshi

    2009-02-15

    BioCichlid is a 3D visualization system of time-course microarray data on molecular networks, aiming at interpretation of gene expression data by transcriptional relationships based on the central dogma with physical and genetic interactions. BioCichlid visualizes both physical (protein) and genetic (regulatory) network layers, and provides animation of time-course gene expression data on the genetic network layer. Transcriptional regulations are represented to bridge the physical network (transcription factors) and genetic network (regulated genes) layers, thus integrating promoter analysis into the pathway mapping. BioCichlid enhances the interpretation of microarray data and allows for revealing the underlying mechanisms causing differential gene expressions. BioCichlid is freely available and can be accessed at http://newton.tmd.ac.jp/. Source codes for both biocichlid server and client are also available.

  19. DISCORDANT GENETIC DIVERSITY AND GEOGRAPHIC PATTERNS BETWEEN CRASSICUTIS CICHLASOMAE (DIGENEA: APOCREADIIDAE) AND ITS CICHLID HOST, "CICHLASOMA" UROPHTHALMUS (OSTEICHTHYES: CICHLIDAE), IN MIDDLE-AMERICA

    National Research Council Canada - National Science Library

    Ulises Razo-Mendivil; Ella Vázquez-Domínguez; Gerardo Pérez-Ponce de León

    2013-01-01

    ...–parasite associations. We evaluated the genetic structure of the digenean Crassicutis cichlasomae and its most common host, the Mayan cichlid "Cichlasoma" urophthalmus, encompassing most of their geographical range in Middle-America...

  20. Assessing the dietary sources of two cichlid species in River Nile sub-branches: Stomach contents, fatty acids and stable isotopes analyses

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    Mohamad S. Abd El-Karim

    2016-06-01

    Full Text Available We assess the importance of four different food sources as dietary components of Oreochromis niloticus and Sarotherodon galilaeus in Nile sub-branches using stomach contents, fatty acids (FA and stable isotopes (SI analyses. Diatoms were the dominant food items, whereas sand and mud constitute a major part of the stomach contents of both cichlids in the northern ElBehery canal. FAs and SI were compared in cichlids and four potential food sources. Carbon isotopes excluded the fresh macrophyte Myriophyllum spicatum and its epiphytes as a potential food source, whereas FA biomarkers indicated that M. spicatum is assimilated in cichlids’ muscles as detrital materials. FA profiles of cichlids’ muscles were highly enriched by live diatom markers whereas decayed diatoms and bacterial markers were partially present. Carbon isotope signatures of cichlids were much close to that of suspended particulate organic matter (SPOM which elucidated that SPOM was the source of diatoms and bacterial detritus incorporated in cichlids muscles. Cichlids were highly enriched with nitrogen signatures which was a result of increased anthropogenic effects and incorporation of bacterial films. SI and FA analyses precisely indicated that live diatoms and bacteria, detrital macrophytes are the main sources of organic matter incorporated in cichlids muscles.

  1. Measles outbreak in young adults in Victoria, 1999.

    Science.gov (United States)

    Lambert, S B; Morgan, M L; Riddell, M A; Andrews, R M; Kelly, H A; Leydon, J A; Catton, M C; Lynch, P A; Gercovich, D K; Lester, R A; Carnie, J A; Rouch, G J

    2000-11-06

    To describe an outbreak of measles in Victoria. Case series with cases identified through enhanced passive surveillance and outbreak-related active surveillance. State of Victoria, 1999. Number of cases; epidemiological links and patterns of transmission; patient demographic features and vaccination status; complications. 75 cases were identified (74 laboratory-confirmed; and one epidemiologically linked to a laboratory-confirmed case), with onset between 11 February and 2 May 1999. The first case was in a 21-year-old woman who had recently holidayed in Bali and worked at a large cinema complex in Melbourne. Sixteen cases occurred in people who had contact with the index case at the cinema on one evening. The outbreak spread to regional Victoria and South Australia. Median age of patients was 22 years; 64 (85%) were born between 1968 and 1981, with only one patient in the age group targeted by the primary school component of the 1998 Australian Measles Control Campaign; this child had not been vaccinated. More than a third of patients (28) were hospitalised (total, 97 inpatient days), and five were healthcare workers. This outbreak was caused by international importation of measles virus. It highlights the change in epidemiology of measles in Australia, from a disease of childhood to one predominantly affecting young adults. A strong two-dose childhood vaccination program, vigilant surveillance, and rapid response to outbreaks will continue to be the basis of measles control, but better protection for young adults should be considered.

  2. Evolutionary dynamics of rRNA gene clusters in cichlid fish

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    Nakajima Rafael T

    2012-10-01

    Full Text Available Abstract Background Among multigene families, ribosomal RNA (rRNA genes are the most frequently studied and have been explored as cytogenetic markers to study the evolutionary history of karyotypes among animals and plants. In this report, we applied cytogenetic and genomic methods to investigate the organization of rRNA genes among cichlid fishes. Cichlids are a group of fishes that are of increasing scientific interest due to their rapid and convergent adaptive radiation, which has led to extensive ecological diversity. Results The present paper reports the cytogenetic mapping of the 5S rRNA genes from 18 South American, 22 African and one Asian species and the 18S rRNA genes from 3 African species. The data obtained were comparatively analyzed with previously published information related to the mapping of rRNA genes in cichlids. The number of 5S rRNA clusters per diploid genome ranged from 2 to 15, with the most common pattern being the presence of 2 chromosomes bearing a 5S rDNA cluster. Regarding 18S rDNA mapping, the number of sites ranged from 2 to 6, with the most common pattern being the presence of 2 sites per diploid genome. Furthermore, searching the Oreochromis niloticus genome database led to the identification of a total of 59 copies of 5S rRNA and 38 copies of 18S rRNA genes that were distributed in several genomic scaffolds. The rRNA genes were frequently flanked by transposable elements (TEs and spread throughout the genome, complementing the FISH analysis that detect only clustered copies of rRNA genes. Conclusions The organization of rRNA gene clusters seems to reflect their intense and particular evolutionary pathway and not the evolutionary history of the associated taxa. The possible role of TEs as one source of rRNA gene movement, that could generates the spreading of ribosomal clusters/copies, is discussed. The present paper reinforces the notion that the integration of cytogenetic data and genomic analysis provides a

  3. Reticulate phylogeny of gastropod-shell-breeding cichlids from Lake Tanganyika – the result of repeated introgressive hybridization

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    Blanc Michel

    2007-01-01

    Full Text Available Abstract Background The tribe Lamprologini is the major substrate breeding lineage of Lake Tanganyika's cichlid species flock. Among several different life history strategies found in lamprologines, the adaptation to live and breed in empty gastropod shells is probably the most peculiar. Although shell-breeding arose several times in the evolutionary history of the lamprologines, all obligatory and most facultative shell-breeders belong to the so called "ossified group", a monophyletic lineage within the lamprologine cichlids. Since their distinctive life style enables these species to live and breed in closest vicinity, we hypothesized that these cichlids might be particularly prone to accidental hybridization, and that introgression might have affected the evolutionary history of this cichlid lineage. Results Our analyses revealed discrepancies between phylogenetic hypotheses based on mitochondrial and nuclear (AFLP data. While the nuclear phylogeny was congruent with morphological, behavioral and ecological characteristics, several species – usually highly specialized shell-breeders – were placed at contradicting positions in the mitochondrial phylogeny. The discordant phylogenies strongly suggest repeated incidents of introgressive hybridization between several distantly related shell-breeding species, which reticulated the phylogeny of this group of cichlids. Long interior branches and high bootstrap support for many interior nodes in the mitochondrial phylogeny argue against a major effect of ancient incomplete lineage sorting on the phylogenetic reconstruction. Moreover, we provide morphological and genetic (mtDNA and microsatellites evidence for ongoing hybridization among distantly related shell-breeders. In these cases, the territorial males of the inferred paternal species are too large to enter the shells of their mate, such that they have to release their sperm over the entrance of the shell to fertilize the eggs. With sperm

  4. Nuclear markers reveal that inter-lake cichlids' similar morphologies do not reflect similar genealogy.

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    Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku

    2006-08-01

    The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.

  5. Quantity discrimination in parental fish: female convict cichlid discriminate fry shoals of different sizes.

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    Forsatkar, Mohammad Navid; Nematollahi, Mohammad Ali; Bisazza, Angelo

    2016-09-01

    Numerical abilities have been found to be adaptive in different contexts, including mating, foraging, fighting assessment and antipredator strategies. In species with parental care, another potential advantage is the possibility to adjust parental behavior in relation to the numerosity of the progeny. The finding that many fish vary their parental investment in relation to brood size advocates the existence of a mechanism for appraising offspring number, an aspect that has never been directly investigated. Here we tested the ability of parental female convict cichlid (Amatitlania nigrofasciata) to discriminate between two fry groups differing in number by measuring time spent attempting to recover groups of fry experimentally displaced from the next. Females spent more time trying to recover the fry from larger groups when tested with contrasts 6 versus 12 (1:2) and 6 versus 9 fry (2:3); however, they showed no preference in the 6 versus 8 (3:4) contrast, suggesting that this task exceeds their discrimination capacity.

  6. Testing the stages model in the adaptive radiation of cichlid fishes in East African Lake Tanganyika

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    Muschick, Moritz; Nosil, Patrik; Roesti, Marius; Dittmann, Marie Theres; Harmon, Luke; Salzburger, Walter

    2014-01-01

    Adaptive radiation (AR) is a key process in the origin of organismal diversity. However, the evolution of trait disparity in connection with ecological specialization is still poorly understood. Available models for vertebrate ARs predict that diversification occurs in the form of temporal stages driven by different selective forces. Here, we investigate the AR of cichlid fishes in East African Lake Tanganyika and use macroevolutionary model fitting to evaluate whether diversification happened in temporal stages. Six trait complexes, for which we also provide evidence of their adaptiveness, are analysed with comparative methods: body shape, pharyngeal jaw shape, gill raker traits, gut length, brain weight and body coloration. Overall, we do not find strong evidence for the ‘stages model’ of AR. However, our results suggest that trophic traits diversify earlier than traits implicated in macrohabitat adaptation and that sexual communication traits (i.e. coloration) diversify late in the radiation. PMID:25274371

  7. Social motivation and conflict resolution tactics as potential building blocks of sociality in cichlid fishes.

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    Balshine, Sigal; Wong, Marian Y L; Reddon, Adam R

    2017-08-01

    Even closely related and ecologically similar cichlid species of Lake Tanganyika exhibit an impressive diversity of social systems, and therefore these fishes offer an excellent opportunity to examine the evolution of social behaviour. Sophisticated social relationships are thought to have evolved via a building block design where more fundamental social behaviours and cognitive processes have been combined, incrementally modified, and elaborated over time. Here, we studied two of these putative social building blocks in two closely related species of cichlids: Neolamprologus pulcher, a group-living species, and Telmatochromis temporalis, a non-grouping species. Otherwise well matched in ecology, this pair of species provide an excellent comparison point to understand how behavioural processes may have been modified in relation to the evolution of sociality. Using social assays in both the laboratory and in the field, we explored each species' motivation to interact with conspecifics, and each species' conflict resolution tactics. We found that individuals of the group living species, N. pulcher, displayed higher social motivation and were more likely to produce submission displays than were individuals of the non-grouping species, T. temporalis. We argue that the motivation to interact with conspecifics is a necessary prerequisite for the emergence of group living, and that the use of submission reduces the costs of conflict and facilitates the maintenance of close social proximity. These results suggest that social motivation and conflict resolution tactics are associated with social complexity, and that these behavioural traits may be functionally significant in the evolution and maintenance of sociality. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Biogeographical implications of Zambezian Cichlidogyrus species (Platyhelminthes: Monogenea: Ancyrocephalidae) parasitizing Congolian cichlids.

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    Vanhove, Maarten P M; Van Steenberge, Maarten; Dessein, Steven; Volckaert, Filip A M; Snoeks, Jos; Huyse, Tine; Pariselle, Antoine

    2013-01-22

    Fishes normally restricted to inland waters are valuable model systems for historical biogeography, inter alia, because of their limited dispersal abilities and concordance with the distribution patterns of other freshwater taxa (Zogaris et al. 2009). The comparison of fish species assemblages has been the major biogeographical tool for delineating African aquatic ecoregions as the fossil record is often meagre and merely offers complementary information. This is, for example, the case for the Zambezian and Congolian ichthyofaunal provinces, which display substantial contemporary fish diversity (Stewart 2001). Between both regions lies the Bangweulu-Mweru ecoregion (sensu Scott 2005), known for its high percentage of endemicity. Although hydrographically belonging to the Congo Basin, the Bangweulu-Mweru ecoregion has a high affinity with the Zambezi province (Scott 2005), due to historical river connections (Tweddle 2010). Studies comparing the Zambezi and Congo ichthyofaunal provinces are rare and hampered by lack of data from the Congo Basin. The latter harbours more than 1250 fish species (Snoeks et al. 2011) while in the Zambezi, only 120 freshwater fishes are found (Tweddle 2010). Indeed, species richness declines in all major African teleost families from the Congo Basin southwards, riverine haplochromine cichlids forming a notable exception to this rule (Joyce et al. 2005). Although it was hypothesized by Tweddle (2010) that the origin of many Zambezian fish species is in the Congo Basin, the haplochromines Serranochromis Regan, Sargochromis Regan, Pharyngochromis Greenwood and Chetia Trewavas, together forming the serranochromines, have their centre of diversity in the rivers of the Zambezian ichthyofaunal province (Joyce et al. 2005). Therefore, the biogeographical history of Cichlidae across the Zambezi- Congo watershed is not only key to cichlid biogeography on an African scale, but also complementary to biogeography of all other teleosts in the region

  9. Crater lake cichlids individually specialize along the benthic–limnetic axis

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    Kusche, Henrik; Recknagel, Hans; Elmer, Kathryn Rebecca; Meyer, Axel

    2014-01-01

    A common pattern of adaptive diversification in freshwater fishes is the repeated evolution of elongated open water (limnetic) species and high-bodied shore (benthic) species from generalist ancestors. Studies on phenotype-diet correlations have suggested that population-wide individual specialization occurs at an early evolutionary and ecological stage of divergence and niche partitioning. This variable restricted niche use across individuals can provide the raw material for earliest stages of sympatric divergence. We investigated variation in morphology and diet as well as their correlations along the benthic-limnetic axis in an extremely young Midas cichlid species, Amphilophus tolteca, endemic to the Nicaraguan crater lake Asososca Managua. We found that A. tolteca varied continuously in ecologically relevant traits such as body shape and lower pharyngeal jaw morphology. The correlation of these phenotypes with niche suggested that individuals are specialized along the benthic-limnetic axis. No genetic differentiation within the crater lake was detected based on genotypes from 13 microsatellite loci. Overall, we found that individual specialization in this young crater lake species encompasses the limnetic-as well as the benthic macro-habitat. Yet there is no evidence for any diversification within the species, making this a candidate system for studying what might be the early stages preceding sympatric divergence. A common pattern of adaptive diversification in freshwater fishes is the repeated evolution of open water (limnetic) species and of shore (benthic) species. Individual specialization can reflect earliest stages of evolutionary and ecological divergence. We here demonstrate individual specialization along the benthic–limnetic axis in a young adaptive radiation of crater lake cichlid fishes. PMID:24772288

  10. Crater lake cichlids individually specialize along the benthic-limnetic axis.

    Science.gov (United States)

    Kusche, Henrik; Recknagel, Hans; Elmer, Kathryn Rebecca; Meyer, Axel

    2014-04-01

    A common pattern of adaptive diversification in freshwater fishes is the repeated evolution of elongated open water (limnetic) species and high-bodied shore (benthic) species from generalist ancestors. Studies on phenotype-diet correlations have suggested that population-wide individual specialization occurs at an early evolutionary and ecological stage of divergence and niche partitioning. This variable restricted niche use across individuals can provide the raw material for earliest stages of sympatric divergence. We investigated variation in morphology and diet as well as their correlations along the benthic-limnetic axis in an extremely young Midas cichlid species, Amphilophus tolteca, endemic to the Nicaraguan crater lake Asososca Managua. We found that A. tolteca varied continuously in ecologically relevant traits such as body shape and lower pharyngeal jaw morphology. The correlation of these phenotypes with niche suggested that individuals are specialized along the benthic-limnetic axis. No genetic differentiation within the crater lake was detected based on genotypes from 13 microsatellite loci. Overall, we found that individual specialization in this young crater lake species encompasses the limnetic-as well as the benthic macro-habitat. Yet there is no evidence for any diversification within the species, making this a candidate system for studying what might be the early stages preceding sympatric divergence. A common pattern of adaptive diversification in freshwater fishes is the repeated evolution of open water (limnetic) species and of shore (benthic) species. Individual specialization can reflect earliest stages of evolutionary and ecological divergence. We here demonstrate individual specialization along the benthic-limnetic axis in a young adaptive radiation of crater lake cichlid fishes.

  11. Aggression and dominance in cichlids in resident-intruder tests: the role of environmental enrichment

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    Vincent Nijman

    2011-01-01

    Full Text Available When establishing dominance residents have a greater likelihood to dominate intruders than vice versa, partially because the resident has more to loose that the intruder has to win. This is known as the prior residency effect. In environmentally rich environments this effect should be stronger than in poor environments. Recently Kadry & Barreto (2010, Neotrop Ichthyol 8: 329-332 tested this in the pearl cichlid Geophagus brasiliensis (17 test pairs and reported that environmental enrichment led to a reduction of aggression. We here present data on four other cichlids (332 test pairs showing a stronger prior residency effect in enriched conditions, and, for two species, an increase in aggression. We discuss possible reasons for the differences between studies, focussing on the relationship between aggression and dominance and sample size effects.No estabelecimento de dominancia, residentes têm uma maior probabilidade de dominar os intrusos que vice-versa, em parte porque o residente tem mais a perder que o invasor tem a ganhar. Isto é conhecido como o efeito de residência prévia. Em ambientes ecologicamente ricos esse efeito deve ser mais forte do que em ambientes pobres. Recentemente Kadry & Barreto (2010, Neotrop. Ichthyol. 8: 329-332 testaram isso no cará Geophagus brasiliensis (17 pares de teste e relataram que o enriquecimento ambiental levou a uma redução de agressão. Aqui apresentamos dados de quatro outros ciclídeos (332 pares de teste, mostrando um efeito mais forte de residência prévia em condições enriquecidas, e, para duas espécies, o aumento da agressão. Discutimos possíveis razões para as diferenças entre os estudos, concentrando-nos sobre a relação entre agressão e dominação e os efeitos do tamanho da amostra.

  12. An examination of injection drug use trends in Victoria and Vancouver, BC after the closure of Victoria's only fixed-site needle and syringe programme.

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    Ivsins, Andrew; Chow, Clifton; Macdonald, Scott; Stockwell, Tim; Vallance, Kate; Marsh, David C; Michelow, Warren; Duff, Cameron

    2012-07-01

    Needle and syringe programmes (NSPs) have been established as effective harm reduction initiatives to reduce injection drug use (IDU)-related risk behaviours, including sharing needles. On May 31, 2008, Victoria, BC's only fixed site NSP was shut down due to community and political pressure. This study examines and compares IDU trends in Victoria with those in Vancouver, BC, a city which has not experienced any similar disruption of IDU-related public health measures. Quantitative and qualitative data were collected by interviewer-administered questionnaires conducted with injection drug users (n=579) in Victoria and Vancouver between late 2007 and late 2010. Needle sharing increased in Victoria from under 10% in early 2008 to 20% in late 2010, whilst rates remained relatively low in Vancouver. Participants in Victoria were significantly more likely to share needles than participants in Vancouver. Qualitative data collected in Victoria highlight the difficulty participants have experienced obtaining clean needles since the NSP closed. Recent injection of crack cocaine was independently associated with needle sharing. The closure of Victoria's fixed site NSP has likely resulted in increased engagement in high-risk behaviours, specifically needle sharing. Our findings highlight the contribution of NSPs as an essential public health measure. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. The African cichlid fish Astatotilapia burtoni uses acoustic communication for reproduction: sound production, hearing, and behavioral significance.

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    Karen P Maruska

    Full Text Available Sexual reproduction in all animals depends on effective communication between signalers and receivers. Many fish species, especially the African cichlids, are well known for their bright coloration and the importance of visual signaling during courtship and mate choice, but little is known about what role acoustic communication plays during mating and how it contributes to sexual selection in this phenotypically diverse group of vertebrates. Here we examined acoustic communication during reproduction in the social cichlid fish, Astatotilapia burtoni. We characterized the sounds and associated behaviors produced by dominant males during courtship, tested for differences in hearing ability associated with female reproductive state and male social status, and then tested the hypothesis that female mate preference is influenced by male sound production. We show that dominant males produce intentional courtship sounds in close proximity to females, and that sounds are spectrally similar to their hearing abilities. Females were 2-5-fold more sensitive to low frequency sounds in the spectral range of male courtship sounds when they were sexually-receptive compared to during the mouthbrooding parental phase. Hearing thresholds were also negatively correlated with circulating sex-steroid levels in females but positively correlated in males, suggesting a potential role for steroids in reproductive-state auditory plasticity. Behavioral experiments showed that receptive females preferred to affiliate with males that were associated with playback of courtship sounds compared to noise controls, indicating that acoustic information is likely important for female mate choice. These data show for the first time in a Tanganyikan cichlid that acoustic communication is important during reproduction as part of a multimodal signaling repertoire, and that perception of auditory information changes depending on the animal's internal physiological state. Our results

  14. Ancestral and derived attributes of the dlx gene repertoire, cluster structure and expression patterns in an African cichlid fish

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    Renz Adina J

    2011-01-01

    Full Text Available Abstract Background Cichlid fishes have undergone rapid, expansive evolutionary radiations that are manifested in the diversification of their trophic morphologies, tooth patterning and coloration. Understanding the molecular mechanisms that underlie the cichlids' unique patterns of evolution requires a thorough examination of genes that pattern the neural crest, from which these diverse phenotypes are derived. Among those genes, the homeobox-containing Dlx gene family is of particular interest since it is involved in the patterning of the brain, jaws and teeth. Results In this study, we characterized the dlx genes of an African cichlid fish, Astatotilapia burtoni, to provide a baseline to later allow cross-species comparison within Cichlidae. We identified seven dlx paralogs (dlx1a, -2a, -4a, -3b, -4b, -5a and -6a, whose orthologies were validated with molecular phylogenetic trees. The intergenic regions of three dlx gene clusters (dlx1a-2a, dlx3b-4b, and dlx5a-6a were amplified with long PCR. Intensive cross-species comparison revealed a number of conserved non-coding elements (CNEs that are shared with other percomorph fishes. This analysis highlighted additional lineage-specific gains/losses of CNEs in different teleost fish lineages and a novel CNE that had previously not been identified. Our gene expression analyses revealed overlapping but distinct expression of dlx orthologs in the developing brain and pharyngeal arches. Notably, four of the seven A. burtoni dlx genes, dlx2a, dlx3b, dlx4a and dlx5a, were expressed in the developing pharyngeal teeth. Conclusion This comparative study of the dlx genes of A. burtoni has deepened our knowledge of the diversity of the Dlx gene family, in terms of gene repertoire, expression patterns and non-coding elements. We have identified possible cichlid lineage-specific changes, including losses of a subset of dlx expression domains in the pharyngeal teeth, which will be the targets of future functional

  15. Phylogeography, colonization and population history of the Midas cichlid species complex (Amphilophus spp. in the Nicaraguan crater lakes

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    Meyer Axel

    2010-10-01

    Full Text Available Abstract Background Elucidation of the mechanisms driving speciation requires detailed knowledge about the phylogenetic relationships and phylogeography of the incipient species within their entire ranges as well as their colonization history. The Midas cichlid species complex Amphilophus spp. has been proven to be a powerful model system for the study of ecological specialization, sexual selection and the mechanisms of sympatric speciation. Here we present a comprehensive and integrative phylogeographic analysis of the complete Midas Cichlid species complex in Nicaragua (> 2000 individuals covering the entire distributional range, using two types of molecular markers (the mitochondrial DNA control region and 15 microsatellites. We investigated the majority of known lake populations of this species complex and reconstructed their colonization history in order to distinguish between alternative speciation scenarios. Results We found that the large lakes contain older and more diverse Midas Cichlid populations, while all crater lakes hold younger and genetically less variable species assemblages. The large lakes appear to have repeatedly acted as source populations for all crater lakes, and our data indicate that faunal exchange among crater lakes is extremely unlikely. Despite their very recent (often only a few thousand years old and common origin from the two large Nicaraguan lakes, all crater lake Midas Cichlid radiations underwent independent, but parallel, evolution, and comprise distinct genetic units. Indeed several of these crater lakes contain multiple genetically distinct incipient species that most likely arose through sympatric speciation. Several crater lake radiations can be traced back to a single ancestral line, but some appear to have more than one founding lineage. The timing of the colonization(s of each crater lake differs, although most of them occurred more (probably much more recently than 20,000 years ago. Conclusion The

  16. Complementary description of Ergasilus arthrosis Roberts, 1969 (Copepoda: Poecilostomatoida: Ergasilidae), a new parasite of cichlid teleosts in southeast Mexico.

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    Jiménez-García, María Isabel; Suárez-Morales, Eduardo

    2017-01-01

    During a parasitological survey of the ichthyofauna of Lake Catemaco, a freshwater system in the Mexican State of Veracruz, the widespread copepod Ergasilus arthrosis Roberts, 1969 was recovered from two cichlid teleosts, Mayaheros urophthalmus (Günther) and Oreochromis sp. This is the first confirmed record of this copepod species outside of the United States and from Mexico; its finding as a parasite of cichlids represents an expansion of the known host range for this copepod. The local prevalence and intensity of infection of E. arthrosis was highest in M. urophthalmus. The infection prevalence of E. arthrosis on M. urophthalmus (60%) was higher than that known for other ergasilids on cichlids. Ergasilus arthrosis can be distinguished from its closest congener E. lizae Krøyer, 1863 by the morphometry of the antennary segments, the ventral ornamentation of the thoracic sclerites and by details of the antennulary setation, but also by its habitat and host preferences. Taxonomic illustrations and morphological details of the specimens examined are also provided together with comments on the variability of this species.

  17. Evolutionary history of the Lake Tanganyika cichlid tribe Lamprologini (Teleostei: Perciformes) derived from mitochondrial and nuclear DNA data

    Science.gov (United States)

    Sturmbauer, Christian; Salzburger, Walter; Duftner, Nina; Schelly, Robert; Koblmüller, Stephan

    2010-01-01

    Lake Tanganyika comprises a cichlid species flock with substrate-breeding and mouthbrooding lineages. While sexual selection via mate choice on male mating color is thought to boost speciation rates in mouthbrooding cichlids, this is not the case in substrate-breeding lamprologines, which mostly form stable pairs and lack sexual dichromatism. We present a comprehensive reconstruction of the evolution of the cichlid tribe Lamprologini, based upon mtDNA sequences and multilocus nuclear DNA (AFLP) markers. Twelve mtDNA clades were identified, seven of which were corroborated by the AFLP tree. The radiation is likely to have started about 5.3 MYA, contemporarily with that of the mouthbrooding C-lineage, and probably triggered by the onset of deep-water conditions in Lake Tanganyika. Neither the Congo- nor the Malagarazi River species form the most ancestral branch. Several conflicts in the mtDNA phylogeny with taxonomic assignments based upon color, eco-morphology and behavior could be resolved and complemented by the AFLP analysis. Introgressive hybridization upon secondary contact seems to be the most likely cause for paraphyly of taxa due to mtDNA capture in species involving brood-care helpers, while accidental hybridization best explains the para- or polyphyly of several gastropod shell breeders. Taxonomic error or paraphyly due to the survival of ancestral lineages appear responsible for inconsistencies in the genera Lamprologus and Neolamprologus. PMID:20601006

  18. Increasing deaths involving oxycodone, Victoria, Australia, 2000-09.

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    Rintoul, Angela C; Dobbin, Malcolm D H; Drummer, Olaf H; Ozanne-Smith, Joan

    2011-08-01

    In light of an emerging epidemic identified in the United States and Canada, to identify trends in fatal drug toxicity involving oxycodone and the demographic characteristics and indicators of socioeconomic disadvantage of the deceased. Population-based observational study in Victoria, Australia. Decedents whose death was reported to the Victorian Coroner between 2000 and 2009 and where oxycodone was detected. Association between supply of oxycodone and deaths. Demographic characteristics of decedents. Rate ratios of the rural or metropolitan location and socioeconomic indicators of disadvantage of the deceased. Supply to Victoria has increased nine-fold from 7.5 mg per capita in 2000 to 67.5 mg per capita in 2009. Detection of oxycodone in deaths reported to the Victorian Coroner has increased from 4 (0.08/100,000 population) in 2000 to 97 (1.78/100,000 population) in 2009-a 21-fold increase in deaths. Of the 320 cases described, 53.8% (172) were the result of drug toxicity. Of these, 52.3% were unintentional and 19.8% intentional self-harm; the remaining 27.9% are either still under investigation by the coroner or intent is unknown. Drug toxicity deaths were overrepresented in both rural areas and areas indexed with high levels of disadvantage. The substantial increase in the number of deaths involving oxycodone is strongly and significantly associated with the increase in supply. Most drug toxicity deaths involving oxycodone were unintentional. This newly identified trend in fatalities in Victoria supports concerns that a pattern of increasing deaths involving oxycodone is emerging globally.

  19. Reforming Victoria's primary health and community service sector: rural implications.

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    Alford, K

    2000-01-01

    In 1999 the Victorian primary care and community support system began a process of substantial reform, involving purchasing reforms and a contested selection process between providers in large catchment areas across the State. The Liberal Government's electoral defeat in September 1999 led to a review of these reforms. This paper questions the reforms from a rural perspective. They were based on a generic template that did not consider rural-urban differences in health needs or other differences including socio-economic status, and may have reinforced if not aggravated rural-urban differences in the quality of and access to primary health care in Victoria.

  20. Exploration of Victoria crater by the mars rover opportunity

    Science.gov (United States)

    Squyres, S. W.; Knoll, A.H.; Arvidson, R. E.; Ashley, James W.; Bell, J.F.; Calvin, W.M.; Christensen, P.R.; Clark, B. C.; Cohen, B. A.; De Souza, P.A.; Edgar, L.; Farrand, W. H.; Fleischer, I.; Gellert, Ralf; Golombek, M.P.; Grant, J.; Grotzinger, J.; Hayes, A.; Herkenhoff, K. E.; Johnson, J. R.; Jolliff, B.; Klingelhofer, G.; Knudson, A.; Li, R.; McCoy, T.J.; McLennan, S.M.; Ming, D. W.; Mittlefehldt, D. W.; Morris, R.V.; Rice, J. W.; Schroder, C.; Sullivan, R.J.; Yen, A.; Yingst, R.A.

    2009-01-01

    The Mars rover Opportunity has explored Victoria crater, a ???750-meter eroded impact crater formed in sulfate-rich sedimentary rocks. Impact-related stratigraphy is preserved in the crater walls, and meteoritic debris is present near the crater rim. The size of hematite-rich concretions decreases up-section, documenting variation in the intensity of groundwater processes. Layering in the crater walls preserves evidence of ancient wind-blown dunes. Compositional variations with depth mimic those ???6 kilometers to the north and demonstrate that water-induced alteration at Meridiani Planum was regional in scope.

  1. Eesti NATO Ühing juurutab demokraatlikke väärtusi / Victoria Punga ; interv. Aive Antsov

    Index Scriptorium Estoniae

    Punga, Victoria, 1977-

    2007-01-01

    Eesti NATO Ühingu tegevjuht organisatsiooni eesmärkidest, projektidest, koostööst teiste riikidega ning kaitsepoliitika ja majanduse seostest. Lisa: Väljavõte Victoria CVst; Eesti kaitsepoliitika viis plussi Victoria meelest

  2. Lunnyu soils in the Lake Victoria basin of Uganda: Link to ...

    African Journals Online (AJOL)

    Lunnyu soils in the Lake Victoria basin of Uganda: Link to toposequence and soil type. B Fungo, S Grunwald, MM Tenywa, B Vanlauwe, P Nkedi-Kizza. Abstract. We compared the physico-chemical characteristics of Lunnyu soils using soil type and slope position in order to explain their variability in the Lake Victoria basin ...

  3. A Snapshot: Multicultural Music Teaching in Schools in Victoria, Australia, Portrayed by School Teachers

    Science.gov (United States)

    Nethsinghe, Rohan Nishantha

    2012-01-01

    Due to the changing demographic factors and as demanded by the governmental policies and regulations, schools in Victoria, Australia, are expected to foster multicultural educational programs that address the diverse needs of students. Research has found that school teachers in Victoria struggle to provide the aspired to multicultural education…

  4. Editorial The “Eye” of Africa: A Vision of Lake Victoria Basin as an ...

    African Journals Online (AJOL)

    AGHOGHO A

    The “Eye” of Africa: A Vision of Lake Victoria Basin as an Environmental. Observatory. Since my days as a schoolboy in geography class, I have not been able to observe maps of the African continent without also “seeing” the profile of a face, with Lake Victoria representing the right eye, gazing adoringly at Madagascar.

  5. Victoria suudlus teeb maapoisist printsi, kuid mitte tulevase kuninga / Kaivo Kopli

    Index Scriptorium Estoniae

    Kopli, Kaivo

    2010-01-01

    Printsess Victoria tulevasest abikaasast Daniel Westlingist, printsess Madelaine'i kihluse lõpetamisest, Bernadotte'ide dünastia asutajast Jean Bernadotte'ist. Monarhia toetajate vähenemisest Rootsis. Printsess Victoria ja Daniel Westlingi pulmatseremooniast 19. juunil

  6. An examination of the selenium nutrition of sheep in Victoria.

    Science.gov (United States)

    Caple, I W; Andrewartha, K A; Edwards, S J; Halpin, C G

    1980-04-01

    The selenium nutrition of sheep throughout Victoria was assessed by a survey of the blood glutathione peroxidase activity in 708 flocks. It was shown that the blood glutathione peroxidase activity in sheep had a seasonal variation with lowest levels in the spring. The enzyme activity was correlated with the blood selenium concentration. Areas where blood selenium was less than 0.03 micrograms/ml in spring were defined. Sheep with low selenium nutrition were grazing pastures in the high rainfall areas on acid soils, particularly those derived from granite. Selenium concentrations in pasture samples examined were greater than 0.02 mg/kg, and it was found that superphosphate application had no significant effect on the selenium content of pasture. However, management practices such as high stocking rates and rates of application of superphosphate to pasture were associated with low blood glutathione peroxidase activities in sheep. It was concluded that the selenium nutrition of most of the sheep flocks in Victoria is adequate, and that the deficient areas are localised. There seems little requirement for supplementation of adult sheep. As the delayed type of white muscle disease in spring lambs appears to be the main selenium-responsive disorder, direct supplementation of lambs in the low selenium areas would be the most effective method of ensuring adequate selenium nutrition.

  7. Epidemiology of the 2012 influenza season in Victoria, Australia

    Directory of Open Access Journals (Sweden)

    James Fielding

    2013-08-01

    Full Text Available Objective: To assess the magnitude and severity of the 2012 influenza season in Victoria, Australia using surveillance data from five sources. Methods: Data from influenza notifications, sentinel general practices, a sentinel hospital network, a sentinel locum service and strain typing databases for 2012 were descriptively analysed. Results: Influenza and influenza-like illness activity was moderate compared to previous years, although a considerable increase in notified laboratory-confirmed influenza was observed. Type A influenza comprised between 83% and 87% of cases from the general practitioners, hospitals and notifiable surveillance data. Influenza A/H3 was dominant in July and August, and most tested isolates were antigenically similar to the A/Perth/16/2009 virus used in the vaccine. There was a smaller peak of influenza type B in September. No tested viruses were resistant to any neuraminidase inhibitor antivirals. Higher proportions of type A/H3, hospitalized cases and those with a comorbid condition indicated for influenza vaccination were aged 65 years or older. Influenza vaccination coverage among influenza-like illness patients was 24% in sentinel general practices and 50% in hospitals. Discussion: The 2012 influenza season in Victoria was average compared to previous years, with an increased dominance of A/H3 accompanied by increases in older and hospitalized cases. Differences in magnitude and the epidemiological profile of cases detected by the different data sources demonstrate the importance of using a range of surveillance data to assess the relative severity of influenza seasons.

  8. Comprehensive nursing education in Victoria: rhetoric or reality?

    Science.gov (United States)

    Happell, B

    2001-12-01

    Significant and widespread changes to the education of the psychiatric nursing workforce in Victoria, Australia are resulting in serious problems in the recruitment of new nursing staff. In reviewing the available literature, it is evident that undergraduate nursing students do not commence their educational program with a strong interest in pursuing a career in psychiatric nursing. In light of this knowledge, the role of education in providing a comprehensive view of the nursing profession becomes paramount. Research investigating the impact of education on the attitudes of students to psychiatric nursing as a career option has produced mixed and often inconclusive results. A longitudinal study was undertaken in Victoria, Australia. Students of the majority of universities in which undergraduate nursing programs were operating participated in this study. The participants were asked to rank nine areas of nursing specialty in order of preference at the commencement and immediately prior to the completion of the nursing program. Despite a significant improvement in the popularity of psychiatric nursing as a career choice, this area was ranked at number 8 at both pre- and post-program test. The analysis of open-ended questions demonstrated a marked change in the overall attitudes towards the mentally ill and psychiatric nursing.

  9. VICTORIA PARK: A DEMOCTRATIC PUBLIC OPEN SPACE FOR INDONESIA DOMESTIC HELPERS (TKW

    Directory of Open Access Journals (Sweden)

    Parmonangan Manurung

    2016-01-01

    Full Text Available Victoria Park is the largest city park in Hong Kong. This city park is not only known in Hong Kong, but also very well known in Indonesia as a gathering place for Indonesia domestic helpers (TKW in Hong Kong. This research tried to find out some determinant factors that have been affected the public open spac of Victoria Park to be a gathering place for thousands of TKW in Sunday and holidays as their day off. In order to get the results of research, some methodological research had been conducted such as: observation (survey, mapping, interviews and literature studies. The results showed that Victoria Park has a number of factors capable of meeting the needs of domestic help-ers in Hong Kong, these factors consist of internal factors and external factors. Internally, the character and functions held Victoria Park became a very influential factor, while externally, the accessibility and support functions around Victoria Park also has a considerable influence.

  10. Ecology and life history of an Amazon floodplain cichlid: the discus fish Symphysodon (Perciformes: Cichlidae

    Directory of Open Access Journals (Sweden)

    William G. R. Crampton

    Full Text Available The discus fishes of the genus Symphysodon are popular ornamental cichlids that occur in floodplain lakes and flooded forests of the lowland Amazon Basin. These habitats are characterized by extreme seasonal fluctuations in the availability of food, shelter and dissolved oxygen, and also the densities of predators and parasites. Most aspects of discus biology are influenced by these fluctuating conditions. This paper reports an autoecological study of the western Amazonian discus S. haraldi (until recently classified as S. aequifasciatus. This species feeds predominantly on algal periphyton, fine organic detritus, plant matter, and small aquatic invertebrates. At high water it forages alone or in small groups in flooded forests. At low water it forms large aggregations in fallen tree crowns along lake margins. Breeding occurs at the beginning of the flood season, ensuring that the progeny are well grown before the next low water period. Symphysodon haraldi is an iteroparous partial spawner, reaches reproductive maturity within a year, and undertakes parental care of its eggs and larvae. The timing of spawning events, and/or the rate of brood survival, may be influenced by fluctuations in the flood level, resulting in a non-unimodal distribution of size classes for the subsequent 1+ cohort.

  11. Phylogeographic Diversity of the Lower Central American Cichlid Andinoacara coeruleopunctatus (Cichlidae

    Directory of Open Access Journals (Sweden)

    S. Shawn McCafferty

    2012-01-01

    Full Text Available It is well appreciated that historical and ecological processes are important determinates of freshwater biogeographic assemblages. Phylogeography can potentially lend important insights into the relative contribution of historical processes in biogeography. However, the extent that phylogeography reflects historical patterns of drainage connection may depend in large part on the dispersal capability of the species. Here, we test the hypothesis that due to their relatively greater dispersal capabilities, the neotropical cichlid species Andinoacara coeruleopunctatus will display a phylogeographic pattern that differs from previously described biogeographic assemblages in this important region. Based on an analysis of 318 individuals using mtDNA ATPase 6/8 sequence and restriction fragment length polymorphism data, we found eight distinct clades that are closely associated with biogeographic patterns. The branching patterns among the clades and a Bayesian clock analysis suggest a relatively rapid colonization and diversification among drainages in the emergent Isthmus of Panama followed by the coalescing of some drainages due to historical connections. We also present evidence for extensive cross-cordillera sharing of clades in central Panama and the Canal region. Our results suggest that contemporary phylogeographic patterns and diversification in Lower Central American fishes reflect an interaction of historical drainage connections, dispersal, and demographic processes.

  12. Rearing-group size determines social competence and brain structure in a cooperatively breeding cichlid.

    Science.gov (United States)

    Fischer, Stefan; Bessert-Nettelbeck, Mathilde; Kotrschal, Alexander; Taborsky, Barbara

    2015-07-01

    Social animals can greatly benefit from well-developed social skills. Because the frequency and diversity of social interactions often increase with the size of social groups, the benefits of advanced social skills can be expected to increase with group size. Variation in social skills often arises during ontogeny, depending on early social experience. Whether variation of social-group sizes affects development of social skills and related changes in brain structures remains unexplored. We investigated whether, in a cooperatively breeding cichlid, early group size (1) shapes social behavior and social skills and (2) induces lasting plastic changes in gross brain structures and (3) whether the development of social skills is confined to a sensitive ontogenetic period. Rearing-group size and the time juveniles spent in these groups interactively influenced the development of social skills and the relative sizes of four main brain regions. We did not detect a sensitive developmental period for the shaping of social behavior within the 2-month experience phase. Instead, our results suggest continuous plastic behavioral changes over time. We discuss how developmental effects on social behavior and brain architecture may adaptively tune phenotypes to their current or future environments.

  13. Morphological Diversity and the Roles of Contingency, Chance and Determinism in African Cichlid Radiations

    Science.gov (United States)

    Young, Kyle A.; Snoeks, Jos; Seehausen, Ole

    2009-01-01

    Background Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance. Methodology/Principal Findings The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance. We then analyzed the morphological diversity of each assemblage independently and compared their axes of diversification in the unconstrained global morphospace. We find that despite differences in phylogenetic composition, invasion history, and ecological setting, the three assemblages are diversifying along parallel axes through morphospace and have nearly identical variance-covariance structures among morphological elements. Conclusions/Significance By demonstrating that replicate adaptive radiations are diverging along parallel axes, we have shown that non-convergence in the common morphospace is associated with convergence in the global morphospace. Applying these complimentary analyses to future comparative studies will improve our understanding of the relationship between morphological convergence and non-convergence, and the roles of contingency, chance and determinism in driving morphological diversification. PMID:19270732

  14. Female preferences for male traits and territory characteristics in the cichlid fishTropheus moorii.

    Science.gov (United States)

    Hermann, Caroline M; Brudermann, Verena; Zimmermann, Holger; Vollmann, Johann; Sefc, Kristina M

    2015-04-01

    Female mate preferences for male traits and resource characteristics affect trait evolution and diversification. Here, we test the effects of male body traits and territory characteristics on within-population female preferences and on population-assortative mating in the cichlid Tropheus moorii . Within-population preferences of females were independent of male body size, coloration and territory size but were strongly dependent on territory quality and co-varied with male courtship activity. Courtship activity of individual males was contingent on the quality of their assigned territory, and therefore, courtship may not only indicate intrinsic male quality. On the basis of these results we suggest that female preferences for high-quality territories reinforce the outcome of malemale competition and ensure male mating success. Mating preferences of females for males of their own color variant (ascertained in a previous experiment) were not overturned when males of another color variant were presented in a superior territory, indicating that within- and between-population mate preferences of females depend on different cues.

  15. Neuromolecular correlates of cooperation and conflict during territory defense in a cichlid fish.

    Science.gov (United States)

    Weitekamp, Chelsea A; Hofmann, Hans A

    2017-03-01

    Cooperative behavior is widespread among animals, yet the neural mechanisms have not been studied in detail. We examined cooperative territory defense behavior and associated neural activity in candidate forebrain regions in the cichlid fish, Astatotilapia burtoni. We find that a territorial male neighbor will engage in territory defense dependent on the perceived threat of the intruder. The resident male, on the other hand, engages in defense based on the size and behavior of his partner, the neighbor. In the neighbor, we find that an index of engagement correlates with neural activity in the putative homolog of the mammalian basolateral amygdala and in the preoptic area, as well as in preoptic dopaminergic neurons. In the resident, neighbor behavior is correlated with neural activity in the homolog of the mammalian hippocampus. Overall, we find distinct neural activity patterns between the neighbor and the resident, suggesting that an individual perceives and processes an intruder challenge differently during cooperative territory defense depending on its own behavioral role. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Startle durations reveal visual assessment abilities during contests between convict cichlids.

    Science.gov (United States)

    Arnott, Gareth; Elwood, Robert W

    2010-07-01

    In animal contests, the widespread ability of contestants to assess their opponents' resource holding potential (RHP) relative to their own, termed mutual assessment, has recently been questioned. It is possible that each contestant may only have information about its own abilities or state, incurring costs up to a particular threshold then giving up, termed self-assessment. We used a technique that provides a measure of fight motivation to discriminate between different assessment models during aggressive encounters between male convict cichlids, Amatitlania nigrofasciata. A novel stimulus was applied to cause a startle response in one contestant of an aggressively interacting, size mis-matched pair, whereby the animal temporarily stops fighting. The time taken to resume the contest has been verified to provide a measure of the motivation to fight, from which it is possible to infer if any visual information concerning opponent asymmetries has been gathered. The data showed support for two differing types of assessment. There was some support for self-assessment, with startle duration being negatively related to own size, and, in a later trial series some support for an opponent only assessment strategy, with startle duration being positively related to opponent size. These results are consistent with individuals learning to use visual information about opponents when deprived of other sensory cues. Evidence within a trial supporting visual mutual assessment was lacking and possible reasons for this are discussed. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  17. Probing aggressive motivation during territorial contests in a group-living cichlid fish.

    Science.gov (United States)

    Reddon, Adam R; Balk, Daniel; Balshine, Sigal

    2013-01-01

    Many animals fight to win resources, repel competitors or establish dominance in a social group. Mutual-assessment of fighting ability, where competitors gather and compare information about their opponent's as well as their own fighting ability has been the dominant theoretical framework for understanding decision-making during fights. However, self-assessment, where each individual has a cost threshold and fights up until that point, may be more common than previously appreciated. In this study, we attempted to discriminate between these two potential assessment mechanisms in a group-living cichlid fish, Neolamprologus pulcher by probing aggressive motivation during a territorial contest. We measured aggressive motivation, and used this metric to investigate assessment rules during an ongoing contest. We predicted that if these social fish use self-assessment, we would observe a positive correlation between the fighting ability of the probed animal and its aggressive motivation. Alternatively, if mutual-assessment is used then we predicted we would find a negative effect of the opponent's fighting ability on the aggressive motivation of the probed fish because fish should be less motivated to fight against formidable opponents. Our results did not support either of these predictions. In contrast we found that small individuals were more aggressively motivated regardless of their opponent's size. We discuss this result in the context of theoretical models of aggression in individuals of small body size. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Evolution of feeding specialization in Tanganyikan scale-eating cichlids: a molecular phylogenetic approach

    Directory of Open Access Journals (Sweden)

    Nishida Mutsumi

    2007-10-01

    Full Text Available Abstract Background Cichlid fishes in Lake Tanganyika exhibit remarkable diversity in their feeding habits. Among them, seven species in the genus Perissodus are known for their unique feeding habit of scale eating with specialized feeding morphology and behaviour. Although the origin of the scale-eating habit has long been questioned, its evolutionary process is still unknown. In the present study, we conducted interspecific phylogenetic analyses for all nine known species in the tribe Perissodini (seven Perissodus and two Haplotaxodon species using amplified fragment length polymorphism (AFLP analyses of the nuclear DNA. On the basis of the resultant phylogenetic frameworks, the evolution of their feeding habits was traced using data from analyses of stomach contents, habitat depths, and observations of oral jaw tooth morphology. Results AFLP analyses resolved the phylogenetic relationships of the Perissodini, strongly supporting monophyly for each species. The character reconstruction of feeding ecology based on the AFLP tree suggested that scale eating evolved from general carnivorous feeding to highly specialized scale eating. Furthermore, scale eating is suggested to have evolved in deepwater habitats in the lake. Oral jaw tooth shape was also estimated to have diverged in step with specialization for scale eating. Conclusion The present evolutionary analyses of feeding ecology and morphology based on the obtained phylogenetic tree demonstrate for the first time the evolutionary process leading from generalised to highly specialized scale eating, with diversification in feeding morphology and behaviour among species.

  19. A test of time-place learning in a cichlid fish.

    Science.gov (United States)

    Reebs, S G

    1993-12-01

    This paper presents a test of time-place learning in fish. Convict cichlids, Cichlasoma nigrofasciatum, were offered food several times a day for 10-30 consecutive days. A signal was given 1 min before each food presentation. If the food was always delivered in the same corner of the aquarium, the fish spent 66% of their time in that corner after the signal was given. But if the food was given in different corners throughout the day, each corner being associated with a specific daily time, the fish failed to show preference for the target corner, even after 30 days. Instead they learned which corners yielded food at any time of the day and visited these corners successively after the feeding signal was given. Failure to associate time and place may have been caused by a low cost of travel between corners, a limited number of rewards each day, and / or interference from learning the signal-food association. Copyright © 1993. Published by Elsevier B.V.

  20. Development of digestive enzymes in larvae of Mayan cichlid Cichlasoma urophthalmus.

    Science.gov (United States)

    López-Ramírez, G; Cuenca-Soria, C A; Alvarez-González, C A; Tovar-Ramírez, D; Ortiz-Galindo, J L; Perales-García, N; Márquez-Couturier, G; Arias-Rodríguez, L; Indy, J R; Contreras-Sánchez, W M; Gisbert, E; Moyano, F J

    2011-03-01

    The development of digestive enzymes during the early ontogeny of the Mayan cichlid (Cichlasoma urophthalmus) was studied using biochemical and electrophoretic techniques. From yolk absorption (6 days after hatching: dah), larvae were fed Artemia nauplii until 15 dah, afterward they were fed with commercial microparticulated trout food (45% protein and 16% lipids) from 16 to 60 dah. Several samples were collected including yolk-sac larvae (considered as day 1 after hatching) and specimens up to 60 dah. Most digestive enzymes were present from yolk absorption (5-6 dah), except for the specific acid proteases activity (pepsin-like), which increase rapidly from 8 dah up to 20 dah. Three alkaline proteases isoforms (24.0, 24.8, 84.5 kDa) were detected at 8 dah using SDS-PAGE zymogram, corresponding to trypsin, chymotrypsin and probably leucine aminopeptidase enzymes, and only one isoform was detected (relative electromobility, Rf = 0.54) for acid proteases (pepsin-like) from 3 dah onwards using PAGE zymogram. We concluded that C. urophthamus is a precocious fish with a great capacity to digest all kinds of food items, including artificial diets provided from 13 dah.

  1. Infection by anisakid nematodes contracaecum spp. in the Mayan cichlid fish 'Cichlasoma (Nandopsis)' urophthalmus (Gunther 1862).

    Science.gov (United States)

    Bergmann, Gaddy T; Motta, Philip J

    2004-04-01

    Larval nematodes that parasitize the Mayan cichlid fish 'Cichlasoma (Nandopsis)' urophthalmus (Günther 1862) in southern Florida were identified as Contracaecum spp. (Nematoda: Anisakidae, Anisakinae). The objective of this study was to determine whether infection intensity and prevalence of these parasites differ between a brackish water and freshwater habitat or through ontogeny in the freshwater habitat only. The nematodes were removed from the abdominal cavity of the fishes and counted. Infection intensity was compared between habitats using analysis of covariance and evaluated through ontogeny using Spearman rank order correlation. Prevalence was compared between habitats and between adults and juveniles from the freshwater habitat using a z-test. Although infection intensity did not differ between habitats, infection prevalence was greater at the freshwater site (FWS). Both the prevalence and intensity of nematode infection increased through ontogeny at the FWS, and no nematode was found in fishes that were smaller than 93 mm standard length. Thus, the parasites appear to accumulate during the lifetime of the fishes.

  2. Experimental Infection of the Mayan Cichlid Cichlasoma urophthalmus with the Oomycete Aphanomyces invadans.

    Science.gov (United States)

    Aguirre-Ayala, Daniel; Vidal-Martínez, Víctor Manuel

    2015-08-01

    This study aimed to determine the susceptibility of the Mayan cichlid Cichlasoma urophthalmus to infection with the fungus Aphanomyces invadans (also known as epizootic ulcerative syndrome [EUS]). A total of 27 C. urophthalmus were exposed to the original A. Invadans 2006/86/EC strain by intramuscularly injecting the fish with 25,000 zoospores/ml or exposing the fish to a suspension of 25,000 zoospores/ml in 6-L aquaria for 30 days. To assess the infectious capacity of A. invadans, 3 golden barbs (Puntius semifasciolatus) were infected intramuscularly with 200,000 zoospores/ml. A second experiment using 100 C. urophthalmus was performed for 60 days with 50 fish in each treatment group. A polymerase chain reaction (PCR)-based diagnostic method was used; muscle and gills were the target tissues. In the first experiment, none of the exposed C. urophthalmus developed skin lesions related to A. invadans infection. However, PCR analysis revealed that infection had occurred. For the intramuscular treatment, there were significant differences between the controls and the muscle samples (Fisher's exact test; P 0.05). All golden barbs became infected, as indicated by PCR, and developed skin lesions typical of A. invadans infection. We concluded that C. urophthalmus was infected with A. invadans but was an asymptomatic carrier because skin lesions did not develop. In the second experiment, all fish were negative, suggesting that the fish had cleared the infection by the end of the experiment.

  3. Partial characterisation of digestive proteases of the Mayan cichlid Cichlasoma urophthalmus.

    Science.gov (United States)

    Cuenca-Soria, C A; Álvarez-González, C A; Ortiz-Galindo, J L; Nolasco-Soria, H; Tovar-Ramírez, D; Guerrero-Zárate, R; Castillo-Domínguez, A; Perera-García, M A; Hernández-Gómez, R; Gisbert, E

    2014-06-01

    The characterisation of digestive proteases in native freshwater fish such as the Mayan cichlid Cichlasoma urophthalmus provides scientific elements that may be used to design balanced feed that matches with the digestive capacity of the fish. The purpose of this study was to characterise the digestive proteases, including the effect of the pH and the temperature on enzyme activity and stability, as well as the effect of inhibitors using multienzymatic extracts of the stomach and intestine of C. urophthalmus juveniles. Results showed that the optimum activities of the acid and alkaline proteases occurred at pH values of 3 and 9, respectively, whereas their optimum temperatures were 55 and 65 °C, respectively. The acid proteases were most stable at pH values of 2–3 and at temperatures of 35–45 °C, whereas the alkaline proteases were most stable at pH values of 6–9 and at 25–55 °C. The inhibition assays recorded a residual activity of 4% with pepstatin A for the acid proteases. The inhibition of the alkaline proteases was greater than 80% with TPCK, TLCK, EDTA and ovalbumin, and of 60 and 43.8% with PMSF and SBT1, respectively. The results obtained in this study make it possible to state that C. urophthalmus has a sufficiently complete digestive enzyme machinery to degrade food items characteristic of an omnivorous fish species, although specimens showed a tendency to carnivory.

  4. Immunocytochemical characterisation of neural stem-progenitor cells from green terror cichlid Aequidens rivulatus.

    Science.gov (United States)

    Wen, C M; Chen, M M; Nan, F H; Wang, C S

    2017-01-01

    In this study, cultures of neural stem-progenitor cells (NSPC) from the brain of green terror cichlid Aequidens rivulatus were established and various NSPCs were demonstrated using immunocytochemistry. All of the NSPCs expressed brain lipid-binding protein, dopamine- and cAMP-regulated neuronal phosphoprotein 32 (DARPP-32), oligodendrocyte transcription factor 2, paired box 6 and sex determining region Y-box 2. The intensity and localisation of these proteins, however, varied among the different NSPCs. Despite being intermediate cells, NSPCs can be divided into radial glial cells, oligodendrocyte progenitor cells (OPC) and neuroblasts by expressing the astrocyte marker glial fibrillary acidic protein (GFAP), OPC marker A2B5 and neuronal markers, including acetyl-tubulin, βIII-tubulin, microtubule-associated protein 2 and neurofilament protein. Nevertheless, astrocytes were polymorphic and were the most dominant cells in the NSPC cultures. By using Matrigel, radial glia exhibiting a long GFAP(+) or DARPP-32(+) fibre and neurons exhibiting a significant acetyl-tubulin(+) process were obtained. The results confirmed that NSPCs obtained from A. rivulatus brains can proliferate and differentiate into neurons in vitro. Clonal culture can be useful for further studying the distinct NSPCs. © 2016 The Fisheries Society of the British Isles.

  5. Feeding in the dark: lateral-line-mediated prey detection in the peacock cichlid Aulonocara stuartgranti.

    Science.gov (United States)

    Schwalbe, Margot A B; Bassett, Daniel K; Webb, Jacqueline F

    2012-06-15

    The cranial lateral line canal system of teleost fishes is morphologically diverse and is characterized by four patterns. One of these, widened lateral line canals, has evolved convergently in a wide range of teleosts, including the Lake Malawi peacock cichlids (Aulonocara), and has been attributed to its role in prey detection. The ability to study Aulonocara in the laboratory provides an opportunity to test the hypothesis that their reported ability to feed on invertebrate prey living in sandy substrates in their natural habitat is the result of lateral-line-mediated prey detection. The goal of this study was to determine whether Aulonocara stuartgranti could detect hydrodynamic stimuli generated by tethered brine shrimp (visualized using digital particle image velocimetry) under light and dark conditions, with and without treatment with cobalt chloride, which is known to temporarily inactivate the lateral line system. Fish were presented with six pairs of tethered live and dead adult brine shrimp and feeding behavior was recorded with HD digital video. Results demonstrate that A. stuartgranti: (1) uses the same swimming/feeding strategy as they do in the field; (2) detects and consumes invertebrate prey in the dark using its lateral line system; (3) alters prey detection behavior when feeding on the same prey under light and dark conditions, suggesting the involvement of multiple sensory modalities; and (4) after treatment with cobalt chloride, exhibits a reduction in their ability to detect hydrodynamic stimuli produced by prey, especially in the dark, thus demonstrating the role of the lateral line system in prey detection.

  6. Comparative development and evolution of two lateral line phenotypes in lake Malawi cichlids.

    Science.gov (United States)

    Webb, Jacqueline F; Bird, Nathan C; Carter, Lauren; Dickson, Juleen

    2014-06-01

    A comparison of the pattern and timing of development of cranial lateral line canals and canal neuromasts in three species of Lake Malawi cichlids, Labeotropheus fuelleborni and Metriaclima zebra (narrow lateral line canals), and Aulonocara baenschi (widened lateral line canals) was used to test the hypothesis that the evolution of widened canals (thought to be an adaptive phenotype in the lateral line system) from narrow canals is the result of heterochrony. Using histological analysis and scanning electron microscopy, this study has provided the first detailed and quantitative description of the development of widened lateral line canals in a teleost, and has demonstrated that: 1) canal neuromast number and the pattern of canal morphogenesis are conserved among species with different adult canal phenotypes, 2) heterochrony ("dissociated heterochrony" in particular) can explain the evolution of widened canals and variation in morphology between canals within a species with respect to canal diameter and neuromast size, and 3) the morphology of the lateral line canals and the dermal bones in which they are found (e.g., the mandibular canal the dentary and anguloarticular bones of the mandible) can evolve independently of each other, thus requiring the addition of another level of complexity to discussions of modularity and integration in the skull of bony fishes. Copyright © 2014 Wiley Periodicals, Inc.

  7. Effect of mate size on maternal reproductive effort in the convict cichlid Amatitlania siquia

    Directory of Open Access Journals (Sweden)

    Ashley R. ROBART

    2012-02-01

    Full Text Available The differential allocation hypothesis predicts individuals will increase their reproductive investment when mated to a high quality partner. In many species of fish with biparental care females prefer large males due to the males’ greater ability to raise more offspring to independence. I examined the relationship between mate quality, parental care and number of offspring in a natural population of convict cichlids Amatitlania siquia. The frequency of frontal displays by females was positively correlated with male standard length. Additionally, as males increased in length relative to their mate, females increased the frequency of chases towards predators, while males decreased the number of displays towards brood predators. This trade-off in parental effort within a pair due to mate quality is a key prediction of differential allocation. The number of offspring was correlated with male, but not female, standard length. These results support the differential allocation hypothesis in that females offered more parental care to offspring of a larger male, while their mates decreased the amount of care they provided. Additionally, females benefited in terms of number of offspring by pairing with higher quality mates. Increased female investment may provide an incentive to ensure male care and maintain pair bonding, which could lead to greater reproductive success through increased offspring survival [Current Zoology 58 (1: 66–72, 2012].

  8. Cultures of astroglial cells derived from brain of adult cichlid fish.

    Science.gov (United States)

    Mack, Andreas F; Tiedemann, Karin

    2013-01-30

    Astroglial cells in teleost fish occur mostly as radial glia. We established a culture system derived from brain tissue of mature cichlid fish Astatotilapia burtoni to study fish astroglial cells in more detail. Cells were passaged several times to expand the cultures, and could be kept in vitro for several months. The cell identity was tested by the presence of glial fibrillary acidic protein (GFAP); in addition, cells expressed the tight junction adaptor protein zonula occludens-1 (ZO-1) known to be present on astroglial cells in fish brain. This is consistent with the radial and epithelial nature of fish astroglial cells derived from neuroepithelium. To characterize the properties of cultured astroglial cells we challenged them in hypo-osmotic conditions. Cells reacted with volume increase, slower but similar to mammalian astrocytes. We also tested whether astroglial cells support growth during axonal elongation. We placed retinal explants on astroglial cultures and found neurites extending readily on these cells, compared to controls which showed no or little growth. Thus, we established a culture system for astroglial cells from the mature fish brain that demonstrates their neuroepithelial properties. This culture system will be useful to study functions in which glial cells are thought to play an important role: e.g. regulation of water homeostasis and supporting axonal regeneration. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Niche divergence facilitated by fine-scale ecological partitioning in a recent cichlid fish adaptive radiation.

    Science.gov (United States)

    Ford, Antonia G P; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K; Balarin, John D; Bruun, Kristoffer; Day, Julia J

    2016-12-01

    Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype-environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large-scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  10. Niche divergence facilitated by fine‐scale ecological partitioning in a recent cichlid fish adaptive radiation

    Science.gov (United States)

    Ford, Antonia G. P.; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K.; Balarin, John D.; Bruun, Kristoffer; Day, Julia J.

    2016-01-01

    Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype‐environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large‐scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. PMID:27659769

  11. Living on the wedge: female control of paternity in a cooperatively polyandrous cichlid.

    Science.gov (United States)

    Kohda, Masanori; Heg, Dik; Makino, Yoshimi; Takeyama, Tomohiro; Shibata, Jun-ya; Watanabe, Katsutoshi; Munehara, Hiroyuki; Hori, Michio; Awata, Satoshi

    2009-12-07

    Theories suggest that, in cooperatively breeding species, female control over paternity and reproductive output may affect male reproductive skew and group stability. Female paternity control may come about through cryptic female choice or female reproductive behaviour, but experimental studies are scarce. Here, we show a new form of female paternity control in a cooperatively polyandrous cichlid fish (Julidochromis transcriptus), in which females prefer wedge-shaped nesting sites. Wedge-shaped sites allowed females to manipulate the siring success of the group member males by spawning the clutch at the spot where the large males were just able to enter and fertilize the outer part of the clutch. Small males fertilized the inner part of the clutch, protected from the large aggressive males, leading to low male reproductive skew. Small males provided more brood care than large males. Multiple paternity induced both males to provide brood care and reduced female brood care accordingly. This is, to our knowledge, the first documented case in a species with external fertilization showing female mating behaviour leading to multiple male paternity and increased male brood care as a result.

  12. Male mate choice scales female ornament allometry in a cichlid fish

    Directory of Open Access Journals (Sweden)

    Kullmann Harald

    2010-10-01

    Full Text Available Abstract Background Studies addressing the adaptive significance of female ornamentation have gained ground recently. However, the expression of female ornaments in relation to body size, known as trait allometry, still remains unexplored. Here, we investigated the allometry of a conspicuous female ornament in Pelvicachromis taeniatus, a biparental cichlid that shows mutual mate choice and ornamentation. Females feature an eye-catching pelvic fin greatly differing from that of males. Results We show that allometry of the female pelvic fin is scaled more positively in comparison to other fins. The pelvic fin exhibits isometry, whereas the other fins (except the caudal fin show negative allometry. The size of the pelvic fin might be exaggerated by male choice because males prefer female stimuli that show a larger extension of the trait. Female pelvic fin size is correlated with individual condition, suggesting that males can assess direct and indirect benefits. Conclusions The absence of positive ornament allometry might be a result of sexual selection constricted by natural selection: fins are related to locomotion and thus may be subject to viability selection. Our study provides evidence that male mate choice might scale the expression of a female sexual ornament, and therefore has implications for the understanding of the relationship of female sexual traits with body size in species with conventional sex-roles.

  13. Male mate choice scales female ornament allometry in a cichlid fish.

    Science.gov (United States)

    Baldauf, Sebastian A; Bakker, Theo C M; Herder, Fabian; Kullmann, Harald; Thünken, Timo

    2010-10-08

    Studies addressing the adaptive significance of female ornamentation have gained ground recently. However, the expression of female ornaments in relation to body size, known as trait allometry, still remains unexplored. Here, we investigated the allometry of a conspicuous female ornament in Pelvicachromis taeniatus, a biparental cichlid that shows mutual mate choice and ornamentation. Females feature an eye-catching pelvic fin greatly differing from that of males. We show that allometry of the female pelvic fin is scaled more positively in comparison to other fins. The pelvic fin exhibits isometry, whereas the other fins (except the caudal fin) show negative allometry. The size of the pelvic fin might be exaggerated by male choice because males prefer female stimuli that show a larger extension of the trait. Female pelvic fin size is correlated with individual condition, suggesting that males can assess direct and indirect benefits. The absence of positive ornament allometry might be a result of sexual selection constricted by natural selection: fins are related to locomotion and thus may be subject to viability selection. Our study provides evidence that male mate choice might scale the expression of a female sexual ornament, and therefore has implications for the understanding of the relationship of female sexual traits with body size in species with conventional sex-roles.

  14. Quantifying mating success of territorial males and sneakers in a bower-building cichlid fish.

    Science.gov (United States)

    Magalhaes, I S; Smith, A M; Joyce, D A

    2017-01-27

    The strategies and traits males evolve to mate with females are incredible in their diversity. Theory on the evolution of secondary sexual characters suggests that evolving any costly trait or strategy will pay off and stabilise in the population if it is advantageous compared to the alternative less costly strategy, but quantifying the relative success of the two can be difficult. In Lake Malawi, Africa, there are >200 species of cichlid fish in which the males form leks and spend several weeks per year building sand-castle "bowers" several times their size. We tested the idea that a less costly "sneaking" strategy could be successful by quantifying the mating success of bower-holding versus non-bower-holding males. We PIT-tagged every fish in a semi-natural experimental set-up and placed tag-readers on the side of bowers to determine which fish held a bower. We then genotyped the eggs removed from females' mouths to assign paternity of each egg. Broods were fathered by up to 3 different males. Although paternity was mostly assigned to males that held a bower, a small number of males who did not own a bower were more successful than some of those that did, indicating a role for an alternative strategy in these bower builders.

  15. Territorial males can sire more offspring in nests with smaller doors in the cichlid Lamprologus lemairii.

    Science.gov (United States)

    Ota, Kazutaka; Awata, Satoshi; Morita, Masaya; Yokoyama, Ryota; Kohda, Masanori

    2014-01-01

    To examine how territorial males counter reproductive parasites, we examined the paternity of broods guarded by territorial males using 5 microsatellite loci and factors that determine siring success in a wild population of the Lake Tanganyika cichlid Lamprologus lemairii. Females enter rock holes (nests) and spawn inside, and territorial males release milt over the nest openings. Sneakers attempt to dart into the nests, but territorial males often interrupt the attempt. The body size of territorial males (territorial defense ability) and the size of nest opening (the ability to prevent sneakers from nest intrusions) are predicted to be factors that affect paternity at the premating stage, whereas milt quality traits are factors that affect paternity at the postmating stage. Parentage analyses of 477 offspring revealed that most clutches have few or no cuckolders, and territorial males sired >80% of eggs in 7 of the 10 analyzed clutches. Larger territorial males that spawned in nests with narrower openings had greater siring success. In contrast, none of the milt traits affected the siring success. These suggest that territorial male L. lemairii adopt premating strategies whereby they effectively prevent reproductive parasitism.

  16. Gross morphology and histology of the alimentary tract of the convict cichlid Amatitlania nigrofasciata.

    Science.gov (United States)

    Hopperdietzel, C; Hirschberg, R M; Hünigen, H; Wolter, J; Richardson, K; Plendl, J

    2014-11-01

    The primary objectives of this study were to document the macroscopic and histological structure of the alimentary tract (AT) of the convict cichlid Amatitlania nigrofasciata, because there are no data available for this omnivorous freshwater fish of the family Cichlidae. The morphology of the AT of A. nigrofasciata resembles that of related species. While having morphological criteria of the AT typical of most omnivorous fishes, such as a blind sac stomach and medium length intestine, A. nigrofasciata also has some structural peculiarities: the oesophagus is lined by a uniform stratified squamous epithelial layer with interspersed goblet cells along its entire length. Additionally, it has well-developed layers of the tunica muscularis including muscle fibre bundles that ascend into its mucosal folds. Occasionally, taste buds are present. In the transitional area between oesophagus and stomach, a prominent torus-like closure device is present. The mucosa of the stomach cannot be divided into different regions according to mucosal and morphological properties. The simple pattern of intestinal loops of A. nigrofasciata has few variations, irrespective of sex, mass and length of the individual fish. The first segment of the intestine is characterized by the largest mucososerosal ratio and the most complex mucosal surface architecture. A distinction of midgut and hindgut was not possible in A. nigrofasciata due to lack of defining structural components as described for other fish species. © 2014 The Fisheries Society of the British Isles.

  17. VENUS - The Victoria Experimental Network Under the Sea: First Light

    Science.gov (United States)

    Dewey, R. K.; Tunnicliffe, V.; Round, A.

    2006-05-01

    The Victoria Experimental Network Under the Sea (VENUS) is a recently installed cabled ocean observatory representing the next generation of infrastructure technology. VENUS is scheduled to consist of two major segments, one in Saanich Inlet (installed in February 2006), and a second in the Strait of Georgia (planned for October 2006). The technologies associated with both the hardware and software that will deliver data from instruments to scientists is being developed in collaboration with both the NEPTUNE Canada and MARS observatories. The presentation will provide an overview of the science projects planned for stage one of the installed instruments, the engineering design of the infrastructure, the preliminary design of the Data Management and Archive System (DMAS), lessons learned so far, and preliminary results from the first few months of data from Saanich Inlet.

  18. Myxomatosis in the Mallee region of Victoria, Australia.

    Science.gov (United States)

    Shepherd, R C; Edmonds, J W; Nolan, I F; Gocs, A

    1978-10-01

    Sharp reductions in the wild rabbit (Oryctolagus cuniculus (L.)) population in the Mallee are associated with annual myxomatosis epizootics. The extent to which the population reductions are the direct result of the epizootics varies with time of epizootic occurrence. All grazing animals in the Mallee are under nutritional stress each summer and autumn. When the epizootic occurs during the early summer heavy losses occur in a previously healthy population. Similar losses which occur in the late summer and autumn are the result of a nutritional stress - epizootic complex. The end result in each case is a population reduction of about 80%. This reduction occurs in a population which is the most resistant to myxomatosis known in Victoria and in association with epizootics caused by field strains of myxoma virus of moderate virulence only. The earlier summer epizootics are of considerable economic importance because they sharply reduce the pressure on the limited food available for other grazing animals.

  19. Literatura y vida. Una lectura de Victoria Ocampo

    Directory of Open Access Journals (Sweden)

    María Celia Vázquez

    2006-09-01

    Full Text Available The relation of literature, writer and life, particularly, the way life is understood within this relation constitutes a key element to define the peculiar way of reading literature that Victoria Ocampo had. This can be seen in her essay on Emily Brontë; though she gives priority to biography over aesthetics, Ocampo does not adopt a biographical approach nor identifies the meaning of life with that of the writer's biography since she searches the key for interpretation in natural forces such as "character" and "fate" (instead of the positivistic interaction of social and historical environment. Thus, she identifies the vital experience of nature (the moors as the key for the writer's personality as well as her novel's, Wuthering Heights.

  20. Color variations on Victoria quadrangle: support for the geological mapping

    Science.gov (United States)

    Zambon, F.; Galluzzi, V.; Carli, C.; Giacomini, L.; Massironi, M.; Palumbo, P.; Guzzetta, L.; Mancinelli, P.; Vivaldi, V.; Ferranti, L.; Pauselli, C.; Frigeri, A.; Zusi, M.; Pozzobon, R.; Cremonese, G.; Ferrari, S.; Capaccioni, F.

    2015-10-01

    Mercury is the closest planet to the Sun. Its extreme thermal environment makes it difficult to explore onsite. In 1974, Mariner 10, the first mission dedicated to Mercury, covered 45% of the surface during of the three Hermean flybys [1]. For about 30 years after Mariner 10, no other mission has flownto Mercury. Many unresolved issues need an answer, and in recent years the interest about Mercury has increased. MESSENGER mission contributed to understand Mercury's origin, its surface structure, and the nature of its magnetic field, exosphere, and magnetosphere [1]. The Mercury Dual Imaging System (MDIS) provided a global coverage of Mercury surface with variable spatial resolution. MDIS is equipped with a narrow angle camera (NAC), dedicated to the study of the geology and a wide angle camera (WAC) with 12 filters useful to investigate the surface composition[2]. Mercury has been divided into 15 quadrangles for mapping purposes [3]. The mapping process permits integration of different geological surface information to better understand the planet crust formation and evolution. Merging spectroscopically data is a poorly followed approach in planetary mapping, but it gives additional information about lithological composition, contributing to the construction of a more complete geological map [e.g. 4]. Recently, [5] proposed a first detailed map of all the Victoria quadrangle (H2). Victoria quadrangle is located in a longitude range between 270°E and 360°E and a latitude range of 22.5°N and 65°N,and itwas only partially mapped by Mariner 10 data[3]. Here we investigate the lithological variation by using the MDIS-WAC data to produce a set of color map products which could be asupport to the geological mapping [5]. The future ESA-JAXA mission to Mercury, BepiColombo, will soon contribute to improve the knowledge of Mercury surface composition and geology thanks to the Spectrometer and Imagers for MPO BepiColombo-Integrated Observatory SYStem (SIMBIO-SYS)[6].

  1. Can convict Cichlids (Amatitlania siquia) socially learn the degree of predation risk associated with novel visual cues in their environment?

    Science.gov (United States)

    Barks, Patrick M; Godin, Jean-Guy J

    2013-01-01

    For many animals, the ability to distinguish cues indicative of predation risk from cues unrelated to predation risk is not entirely innate, but rather is learned and improved with experience. Two pathways to such learning are possible. First, an animal could initially express antipredator behaviour toward a wide range of cues and subsequently learn which of those cues are non-threatening. Alternatively, it could initially express no antipredator behaviour toward a wide range of cues and subsequently learn which of them are threatening. While the learned recognition of threatening cues may occur either through personal interaction with a cue (asocial learning) or through observation of the behaviour of social companions toward a cue (social learning), the learned recognition of non-threatening cues seems to occur exclusively through habituation, a form of asocial learning. Here, we tested whether convict cichlid fish (Amatitlaniasiquia) can socially learn to recognize visual cues in their environment as either threatening or non-threatening. We exposed juvenile convict cichlids simultaneously to a novel visual cue and one of three (visual) social cues: a social cue indicative of non-risk (the sight of conspecifics that had previously been habituated to the novel cue), a social cue indicative of predation risk (the sight of conspecifics trained to fear the novel cue), or a control treatment with no social cue. The subsequent response of focal fish, when presented with the novel cue alone, was not influenced by the social cue that they had previously witnessed. We therefore did not find evidence that convict cichlids in our study could use social learning to recognize novel visual cues as either threatening or non-threatening. We consider alternative explanations for our findings.

  2. Can convict Cichlids (Amatitlania siquia socially learn the degree of predation risk associated with novel visual cues in their environment?

    Directory of Open Access Journals (Sweden)

    Patrick M Barks

    Full Text Available For many animals, the ability to distinguish cues indicative of predation risk from cues unrelated to predation risk is not entirely innate, but rather is learned and improved with experience. Two pathways to such learning are possible. First, an animal could initially express antipredator behaviour toward a wide range of cues and subsequently learn which of those cues are non-threatening. Alternatively, it could initially express no antipredator behaviour toward a wide range of cues and subsequently learn which of them are threatening. While the learned recognition of threatening cues may occur either through personal interaction with a cue (asocial learning or through observation of the behaviour of social companions toward a cue (social learning, the learned recognition of non-threatening cues seems to occur exclusively through habituation, a form of asocial learning. Here, we tested whether convict cichlid fish (Amatitlaniasiquia can socially learn to recognize visual cues in their environment as either threatening or non-threatening. We exposed juvenile convict cichlids simultaneously to a novel visual cue and one of three (visual social cues: a social cue indicative of non-risk (the sight of conspecifics that had previously been habituated to the novel cue, a social cue indicative of predation risk (the sight of conspecifics trained to fear the novel cue, or a control treatment with no social cue. The subsequent response of focal fish, when presented with the novel cue alone, was not influenced by the social cue that they had previously witnessed. We therefore did not find evidence that convict cichlids in our study could use social learning to recognize novel visual cues as either threatening or non-threatening. We consider alternative explanations for our findings.

  3. Critical Comments on Brian Victoria's "Engaged Buddhism: Skeleton in the Closet?"

    Directory of Open Access Journals (Sweden)

    Koichi Miyata

    2015-02-01

    Full Text Available In "Engaged Buddhism: A Skeleton in the Closet?" (Vol. 2 Brian Daizen Victoria claims, among other things, that Tsunesaburo Makiguchi (1871-1944, founder of the Soka Kyoiku Gakkai (forebear of the Soka Gakkai and Soka Gakkai International, was an active supporter of the Japanese wars of aggression. In this response, Koichi Miyata argues that Victoria's claims rest on the highly selective use of quotes, and ignore key interpretative issues associated with Japanese imperial fascism and its underlying belief structures. Miyata discusses the significance of Makiguchi's arrest and imprisonment under a law specifically aimed at opponents of the war efforts, in his analysis of critical lapses in Victoria's article.

  4. Testing for differences in rates of speciation, extinction, and morphological evolution in four tribes of cichlids endemic to Lake Tanganyika, East Africa.

    Science.gov (United States)

    Hoerner, Marie E

    2011-12-01

    Patterns of morphological disparity yield important insight into the causes of diversification and adaptive radiation in East African cichlids. However, comparisons of cichlid disparity have often failed to consider the effects that differing clade ages or stochasticity may have on disparity before making interpretations. Here, a model of branching morphological evolution allows assessment of the relative contributions of differing turnover and morphological change rates, clade ages, and stochastic variation to the observed patterns of disparity in four endemic tribes of Lake Tanganyika cichlids. Simulations compare the likelihood of generating the observed disparity of the four tribes using 200-parameter combinations and four model conditioning variations, which allows inference of evolutionary rate differences among clades. The model is generally robust to model conditioning, the approach to data analysis, and model assumptions. Disparity differences among the first three cichlid tribes, Ectodini, Lamprologini, and Tropheini, can be explained entirely by stochasticity and age, whereas the fourth tribe, Cyprichromini, has likely experienced lower rates of turnover and morphological change. This rate difference is likely related to the low dietary diversity of the Cyprichromini. These results highlight the importance of considering both clade age and stochastic variation when interpreting morphological diversity and evolutionary processes. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  5. The cichlid genus Crenicichla from the Tocantins river, State of Pará, Brazil, with descriptions of four new species (Pisces, Perciformes, Cichlidae)

    NARCIS (Netherlands)

    Ploeg, A.

    1986-01-01

    A large collection of fish specimens assembled by the Instituto Nacional de Pesquisas da Amazônia (INPA) in the Tocantins River, State of Pará, Brazil yielded nine species (four of which are new) of the cichlid genus Crenicichla; C. astroblepa n. sp.; C. compressiceps n. sp.; C. cyclostoma n. sp.;

  6. Disturbance cues in freshwater prey fishes: Does urea function as an ‘early warning cue’in juvenile convict cichlids and rainbow trout?

    Directory of Open Access Journals (Sweden)

    Grant E. BROWN, Christopher D. JACKSON, Patrick H. MALKA,Élisa JACQUES, Marc-Andre COUTURIER

    2012-04-01

    Full Text Available Freshwater vertebrate and invertebrate prey species commonly rely on chemosensory information, including non-injury released disturbance cues, to assess local predation threats. We conducted laboratory studies to (1 determine if urea can function as a disturbance cue in juvenile convict cichlids and rainbow trout and (2 determine if the background level of urea influences the behavioral response to a subsequent pulse of urea (‘background noise’ hypothesis. In the first series of trials, juvenile cichlids and trout were exposed to urea at varying concentrations (0 to 0.5 mg L-1 for cichlids and 0 to 1.0 mg L-1 for trout. Our results suggest that both cichilds and trout exhibited functionally similar responses to urea and conspecific disturbance cues and that increasing the concentration of urea results in an increase intensity of antipredator behaviour. In the second series of trials, we pre-exposed cichlids or trout to intermediate or high concentrations of urea (or a distilled water control and then tested for the response to a second pulse of urea at at intermediate or high concentrations (versus a distilled water control. Our results demonstrate that pre-exposure to urea reduces or eliminates the response to a second pulse of urea, supporting the background noise hypothesis. Together, our results suggest that pulses of urea, released by disturbed or stressed individuals, may function as an early warning signal in freshwater prey species [Current Zoology 58 (2: 250–259 , 2012].

  7. End‐of‐life decisions in medical practice: a survey of doctors in Victoria (Australia)

    Science.gov (United States)

    Neil, D A; Coady, C A J; Thompson, J; Kuhse, H

    2007-01-01

    Objectives To discover the current state of opinion and practice among doctors in Victoria, Australia, regarding end‐of‐life decisions and the legalisation of voluntary euthanasia. Longitudinal comparison with similar 1987 and 1993 studies. Design and participants Cross‐sectional postal survey of doctors in Victoria. Results 53% of doctors in Victoria support the legalisation of voluntary euthanasia. Of doctors who have experienced requests from patients to hasten death, 35% have administered drugs with the intention of hastening death. There is substantial disagreement among doctors concerning the definition of euthanasia. Conclusions Disagreement among doctors concerning the meaning of the term euthanasia may contribute to misunderstanding in the debate over voluntary euthanasia. Among doctors in Victoria, support for the legalisation of voluntary euthanasia appears to have weakened slightly over the past 17 years. Opinion on this issue is sharply polarised. PMID:18055904

  8. Eutrophication, Nile perch and food-web interactions in south-east Lake Victoria

    NARCIS (Netherlands)

    Cornelissen, I.J.M.

    2015-01-01

    The increasing eutrophication, the introduction of Nile perch (Lates niloticus) and the increasing fishing pressure has changed Lake Victoria tremendously the last century. Since the 1960s, eutrophication increased primary production, enabling an increase in fish production. However, eutrophication

  9. Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica

    Directory of Open Access Journals (Sweden)

    Byron Adams

    2014-06-01

    Full Text Available The terrestrial ecosystems of Victoria Land, Antarctica are characteristically simple in terms of biological diversity and ecological functioning. Nematodes are the most commonly encountered and abundant metazoans of Victoria Land soils, yet little is known of their diversity and distribution. Herein we present a summary of the geographic distribution, habitats and ecology of the terrestrial nematodes of Victoria Land from published and unpublished sources. All Victoria Land nematodes are endemic to Antarctica, and many are common and widely distributed at landscape scales. However, at smaller spatial scales, populations can have patchy distributions, with the presence or absence of each species strongly influenced by specific habitat requirements. As the frequency of nematode introductions to Antarctica increases, and soil habitats are altered in response to climate change, our current understanding of the environmental parameters associated with the biogeography of Antarctic nematofauna will be crucial to monitoring and possibly mitigating changes to these unique soil ecosystems.

  10. Analysis of an Organisation: A University of the Third Age (U3A), Mornington, Victoria

    Science.gov (United States)

    Small, Michael

    2017-01-01

    The purpose of this paper is two fold: to look at Mornington U3A in organisational terms and then look at U3AM as a loosely coupled system. One outcome of the study would be to undertake further analyses of U3As in Victoria to determine the levels of bureaucracy under which each operates. Questions to be asked: are U3As in Victoria operating as…

  11. Sensitivity analysis of the GNSS derived Victoria plate motion

    Science.gov (United States)

    Apolinário, João; Fernandes, Rui; Bos, Machiel

    2014-05-01

    Fernandes et al. (2013) estimated the angular velocity of the Victoria tectonic block from geodetic data (GNSS derived velocities) only.. GNSS observations are sparse in this region and it is therefore of the utmost importance to use the available data (5 sites) in the most optimal way. Unfortunately, the existing time-series were/are affected by missing data and offsets. In addition, some time-series were close to the considered minimal threshold value to compute one reliable velocity solution: 2.5-3.0 years. In this research, we focus on the sensitivity of the derived angular velocity to changes in the data (longer data-span for some stations) by extending the used data-span: Fernandes et al. (2013) used data until September 2011. We also investigate the effect of adding other stations to the solution, which is now possible since more stations became available in the region. In addition, we study if the conventional power-law plus white noise model is indeed the best stochastic model. In this respect, we apply different noise models using HECTOR (Bos et al. (2013), which can use different noise models and estimate offsets and seasonal signals simultaneously. The seasonal signal estimation is also other important parameter, since the time-series are rather short or have large data spans at some stations, which implies that the seasonal signals still can have some effect on the estimated trends as shown by Blewitt and Lavellee (2002) and Bos et al. (2010). We also quantify the magnitude of such differences in the estimation of the secular velocity and their effect in the derived angular velocity. Concerning the offsets, we investigate how they can, detected and undetected, influence the estimated plate motion. The time of offsets has been determined by visual inspection of the time-series. The influence of undetected offsets has been done by adding small synthetic random walk signals that are too small to be detected visually but might have an effect on the

  12. Compositional variations on Mercury: Results from the Victoria quadrangle

    Science.gov (United States)

    Zambon, Francesca; Carli, Cristian; Galluzzi, Valentina; Capaccioni, Fabrizio; Giacomini, Lorenza; Massironi, Matteo; Palumbo, Pasquale; Cremonese, Gabriele

    2017-04-01

    Mercury was recently explored by the MESSENGER mission that orbited around the planet from March 2011 until April 2015 allowing a complete coverage of its surface. The Mercury Dual Imaging System (MDIS), mapped the Hermean surface at different spatial resolutions, due to variable altitude of the spacecraft from the surface. MDIS consists of two instruments: a Narrow Angle Camera (NAC) centered at 747nm, which acquired high-resolution images for the geological analysis, and the Wide Angle Camera (WAC), provided with 11 filters dedicated to the compositional analysis, operating in a range of wavelengths between 395 and 1040 nm. Mercury's surface has been divided into 15 quadrangles for mapping purposes. Here, we analyze the results obtained by the color composite mosaic of the quadrangle Victoria (H02) located at longitudes 270 ° - 360 ° E, and latitudes 22.5 ° N - 65 ° N. We produced a color mosaic, by using the images relative to the filters with the best spatial coverage. To obtain the 8-color mosaic of the Victoria quadrangle, we calibrated and georefenced the WAC raw images. Afterwards, we applied the Hapke photometric correction by using the parameters derived by Domingue et al. (2015). We projected and coregistered the data, and finally, we produced the mosaic. To analyze the compositional variations of the Victoria quadrangle, we consider different techniques of analysis, such as specific RGB color combinations and band ratios, which emphasize the different compositional characteristics of the surface. Furthermore, the use of clustering and classification methods allows for recognizing various terrain units, in terms of reflectance and spectral characteristics. In the H02 quadrangle, we observed a dichotomy in the RGB mosaic (R: second principal component (PC2), G: first principal component (PC1), B: 430/1000 nm; see Denevi et al. 2009) between the northern region of the quadrangle, dominated by smooth plains, and the southern part, characterized by

  13. Two types of dominant male cichlid fish: behavioral and hormonal characteristics

    Directory of Open Access Journals (Sweden)

    Rosa M. Alcazar

    2016-08-01

    Full Text Available Male African cichlid fish, Astatotilapia burtoni, have been classified as dominant or subordinate, each with unique behavioral and endocrine profiles. Here we characterize two distinct subclasses of dominant males based on types of aggressive behavior: (1 males that display escalating levels of aggression and court females while they establish a territory, and (2 males that display a stable level of aggression and delay courting females until they have established a territory. To profile differences in their approach to a challenge, we used an intruder assay. In every case, there was a male-male confrontation between the resident dominant male and the intruder, with the intruder quickly taking a subordinate role. However, we found that dominant males with escalating aggression spent measurably more time attacking subordinates than did dominant males with stable aggression that instead increased their attention toward the females in their tank. There was no difference in the behavior of intruders exposed to either type of dominant male, suggesting that escalating aggression is an intrinsic characteristic of some dominant males and is not elicited by the behavior of their challengers. Male behavior during the first 15 min of establishing a territory predicts their aggressive class. These two types of dominant males also showed distinctive physiological characteristics. After the intruder assay, males with escalating aggression had elevated levels of 11-ketotestosterone (11-KT, testosterone, estradiol, and cortisol, while those with stable aggression did not. These observations show that the same stimulus can elicit different behavioral and endocrine responses among A. burtoni dominant males that characterize them as either escalating or stable aggressive types. Our ability to identify which individuals within a population have escalating levels of aggressive responses versus those which have stable levels of aggressive responses when exposed to

  14. Growth and social behavior in a cichlid fish are affected by social rearing environment and kinship

    Science.gov (United States)

    Hesse, Saskia; Thünken, Timo

    2014-04-01

    Living in groups is a widespread phenomenon in many animal taxa. The reduction of predation risk is thought to be an important cause for the formation of groups. Consequently, grouping behavior is particularly pronounced during vulnerable life stages, i.e., as juveniles. However, group living does not only provide benefits but also imposes costs on group members, e.g., increased competition for food. Thus, benefits of grouping behavior might not be evident when predation risk is absent. The adaptive significance of living and also developing in a group independent from predation risk has received relatively little attention although this might have important implications on the evolution and maintenance of group living. The first aim of the present study was to examine whether the social environment affects juvenile performance in the cichlid fish Pelvicachromis taeniatus and, secondly, whether kinship affects social behavior. Kin selection theory predicts benefits from grouping with kin. Here, we demonstrate that juveniles reared in a group grow on average faster compared to juveniles reared in isolation under standardized laboratory conditions without predation risk. Furthermore, we found significant differences in social behavior between juveniles reared in a group and reared in isolation. Fish reared in isolation were significantly more aggressive and less willing to shoal than group-reared fish. As expected, genetic relatedness influenced social behavior in group-reared fish as well: dyads of juveniles consisting of kin showed increased group cohesiveness compared to non-kin dyads. We discuss the potential benefits of group living in general and living with kin in particular.

  15. Background matching ability and the maintenance of a colour polymorphism in the red devil cichlid.

    Science.gov (United States)

    Sowersby, W; Lehtonen, T K; Wong, B B M

    2015-02-01

    The evolution and maintenance of colour polymorphisms remains a topic of considerable research interest. One key mechanism thought to contribute to the coexistence of different colour morphs is a bias in how conspicuous they are to visual predators. Although individuals of many species camouflage themselves against their background to avoid predation, differently coloured individuals within a species may vary in their capacity to do so. However, to date, very few studies have explicitly investigated the ability of different colour morphs to plastically adjust their colouration to match their background. The red devil (Amphilophus labiatus) is a Neotropical cichlid fish with a stable colour polymorphism, with the gold morph being genetically dominant and having a myriad of documented advantages over the dark morph. However, gold individuals are much rarer, which may be related to their heightened conspicuousness to would-be predators. Here, we tested the ability of differently coloured individuals to phenotypically adjust the shade of their body colour and patterns to match their background. In particular, we filmed dark, gold and mottled (a transitioning phase from dark to gold) individuals under an identical set-up on light vs. dark-coloured substrates. We found that, in contrast to individuals of the dark morph, gold and mottled individuals were less capable of matching their body colouration to their background. As a result, gold individuals appeared to be more conspicuous. These results suggest that a difference in background matching ability could play an important role in the maintenance of colour polymorphisms. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  16. Detection of artificial water flows by the lateral line system of a benthic feeding cichlid fish.

    Science.gov (United States)

    Schwalbe, Margot A B; Sevey, Benjamin J; Webb, Jacqueline F

    2016-04-01

    The mechanosensory lateral line system of fishes detects water motions within a few body lengths of the source. Several types of artificial stimuli have been used to probe lateral line function in the laboratory, but few studies have investigated the role of flow sensing in benthic feeding teleosts. In this study, we used artificial flows emerging from a sandy substrate to assess the contribution of flow sensing to prey detection in the peacock cichlid, Aulonocara stuartgranti, which feeds on benthic invertebrates in Lake Malawi. Using a positive reinforcement protocol, we trained fish to respond to flows lacking the visual and chemical cues generated by tethered prey in prior studies with A. stuartgranti Fish successfully responded to artificial flows at all five rates presented (characterized using digital particle image velocimetry), and showed a range of flow-sensing behaviors, including an unconditioned bite response. Immediately after lateral line inactivation, fish rarely responded to flows and the loss of vital fluorescent staining of hair cells (with 4-di-2-ASP) verified lateral line inactivation. Within 2 days post-treatment, some aspects of flow-sensing behavior returned and after 7 days, flow-sensing behavior and hair cell fluorescence both returned to pre-treatment levels, which is consistent with the reported timing of hair cell regeneration in other vertebrates. The presentation of ecologically relevant water flows to assess flow-sensing behaviors and the use of a positive reinforcement protocol are methods that present new opportunities to study the role of flow sensing in the feeding ecology of benthic feeding fishes. © 2016. Published by The Company of Biologists Ltd.

  17. Quantitative Molecular Phenotyping of Gill Remodeling in a Cichlid Fish Responding to Salinity Stress*

    Science.gov (United States)

    Kültz, Dietmar; Li, Johnathon; Gardell, Alison; Sacchi, Romina

    2013-01-01

    A two-tiered label-free quantitative (LFQ) proteomics workflow was used to elucidate how salinity affects the molecular phenotype, i.e. proteome, of gills from a cichlid fish, the euryhaline tilapia (Oreochromis mossambicus). The workflow consists of initial global profiling of relative tryptic peptide abundances in treated versus control samples followed by targeted identification (by MS/MS) and quantitation (by chromatographic peak area integration) of validated peptides for each protein of interest. Fresh water acclimated tilapia were independently exposed in separate experiments to acute short-term (34 ppt) and gradual long-term (70 ppt, 90 ppt) salinity stress followed by molecular phenotyping of the gill proteome. The severity of salinity stress can be deduced with high technical reproducibility from the initial global label-free quantitative profiling step alone at both peptide and protein levels. However, an accurate regulation ratio can only be determined by targeted label-free quantitative profiling because not all peptides used for protein identification are also valid for quantitation. Of the three salinity challenges, gradual acclimation to 90 ppt has the most pronounced effect on gill molecular phenotype. Known salinity effects on tilapia gills, including an increase in the size and number of mitochondria-rich ionocytes, activities of specific ion transporters, and induction of specific molecular chaperones are reflected in the regulation of abundances of the corresponding proteins. Moreover, specific protein isoforms that are responsive to environmental salinity change are resolved and it is revealed that salinity effects on the mitochondrial proteome are nonuniform. Furthermore, protein NDRG1 has been identified as a novel key component of molecular phenotype restructuring during salinity-induced gill remodeling. In conclusion, besides confirming known effects of salinity on gills of euryhaline fish, molecular phenotyping reveals novel insight into

  18. Quantitative molecular phenotyping of gill remodeling in a cichlid fish responding to salinity stress.

    Science.gov (United States)

    Kültz, Dietmar; Li, Johnathon; Gardell, Alison; Sacchi, Romina

    2013-12-01

    A two-tiered label-free quantitative (LFQ) proteomics workflow was used to elucidate how salinity affects the molecular phenotype, i.e. proteome, of gills from a cichlid fish, the euryhaline tilapia (Oreochromis mossambicus). The workflow consists of initial global profiling of relative tryptic peptide abundances in treated versus control samples followed by targeted identification (by MS/MS) and quantitation (by chromatographic peak area integration) of validated peptides for each protein of interest. Fresh water acclimated tilapia were independently exposed in separate experiments to acute short-term (34 ppt) and gradual long-term (70 ppt, 90 ppt) salinity stress followed by molecular phenotyping of the gill proteome. The severity of salinity stress can be deduced with high technical reproducibility from the initial global label-free quantitative profiling step alone at both peptide and protein levels. However, an accurate regulation ratio can only be determined by targeted label-free quantitative profiling because not all peptides used for protein identification are also valid for quantitation. Of the three salinity challenges, gradual acclimation to 90 ppt has the most pronounced effect on gill molecular phenotype. Known salinity effects on tilapia gills, including an increase in the size and number of mitochondria-rich ionocytes, activities of specific ion transporters, and induction of specific molecular chaperones are reflected in the regulation of abundances of the corresponding proteins. Moreover, specific protein isoforms that are responsive to environmental salinity change are resolved and it is revealed that salinity effects on the mitochondrial proteome are nonuniform. Furthermore, protein NDRG1 has been identified as a novel key component of molecular phenotype restructuring during salinity-induced gill remodeling. In conclusion, besides confirming known effects of salinity on gills of euryhaline fish, molecular phenotyping reveals novel insight into

  19. Allometric shape change of the lower pharyngeal jaw correlates with a dietary shift to piscivory in a cichlid fish

    Science.gov (United States)

    Hellig, Christoph J.; Kerschbaumer, Michaela; Sefc, Kristina M.; Koblmüller, Stephan

    2010-07-01

    The morphological versatility of the pharyngeal jaw of cichlid fishes is assumed to represent a key factor facilitating their unparalleled trophic diversification and explosive radiation. It is generally believed that the functional design of an organism relates to its ecology, and thus, specializations to different diets are typically associated with distinct morphological designs, especially manifested in the cichlids’ pharyngeal jaw apparatus. Thereby, the lower pharyngeal jaw (LPJ) incorporates some of the most predictive features for distinct diet-related morphotypes. Thus, considering that piscivorous cichlids experience an ontogenetic dietary shift from typically various kinds of invertebrates to fish, concomitant morphological changes in the LPJ are expected. Using Lepidiolamprologus elongatus, a top predator in the shallow rocky habitat of Lake Tanganyika, as model, and applying geometric and traditional morphometric techniques, we demonstrate an allometric change in ontogenetic LPJ shape development coinciding with the completion of the dietary shift toward piscivory. The piscivorous LPJ morphotype is initiated in juvenile fish by increasing elongation and narrowing of the LPJ and—when the fish reach a size of 80-90 mm standard length—further refined by the elongation of the posterior muscular processes, which serve as insertion for the fourth musculus levator externus. The enlarged muscular processes of the fully mature piscivorous morphotype provide for the construction of a powerful lever system, which allows the large individuals to process large prey fish and rely on exclusive piscivory.

  20. Evolution of opercle shape in cichlid fishes from Lake Tanganyika - adaptive trait interactions in extant and extinct species flocks.

    Science.gov (United States)

    Wilson, Laura A B; Colombo, Marco; Sánchez-Villagra, Marcelo R; Salzburger, Walter

    2015-11-20

    Phenotype-environment correlations and the evolution of trait interactions in adaptive radiations have been widely studied to gain insight into the dynamics underpinning rapid species diversification. In this study we explore the phenotype-environment correlation and evolution of operculum shape in cichlid fishes using an outline-based geometric morphometric approach combined with stable isotope indicators of macrohabitat and trophic niche. We then apply our method to a sample of extinct saurichthyid fishes, a highly diverse and near globally distributed group of actinopterygians occurring throughout the Triassic, to assess the utility of extant data to inform our understanding of ecomorphological evolution in extinct species flocks. A series of comparative methods were used to analyze shape data for 54 extant species of cichlids (N = 416), and 6 extinct species of saurichthyids (N = 44). Results provide evidence for a relationship between operculum shape and feeding ecology, a concentration in shape evolution towards present along with evidence for convergence in form, and significant correlation between the major axes of shape change and measures of gut length and body elongation. The operculum is one of few features that can be compared in extant and extinct groups, enabling reconstruction of phenotype-environment interactions and modes of evolutionary diversification in deep time.

  1. Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepagua Lake, Rio de Janeiro, Brazil

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    Parente, Thiago E.M.; Oliveira, Ana C.A.X. de [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil); Paumgartten, Francisco J.R. [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil)], E-mail: paum@ensp.fiocruz.br

    2008-03-15

    The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ('Nile tilapia', Oreochromis niloticus and 'acara', Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepagua Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes. - Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals.

  2. Genetic evidence for multiple sources of the non-native fish Cichlasoma urophthalmus (Günther; Mayan Cichlids in southern Florida.

    Directory of Open Access Journals (Sweden)

    Elizabeth Harrison

    Full Text Available The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid. Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids from the upper Yucatán Peninsula to Guatemala and introductions from Guatemala and Belize to Florida. The mismatch between mitochondrial and nuclear genomes suggests admixture of a female lineage from Guatemala, where all individuals were fixed for the mitochondrial haplotype found in the introduced population, and a more diverse but also relatively small number of individuals from Belize. The Florida cytochrome b haplotype appears to be absent from Belize (0 out of 136 fish screened from Belize had this haplotype. Genetic structure within the Florida population was minimal, indicating a panmictic population, while Mexican and Central American samples displayed more genetic subdivision. Individuals from the Upper Yucatán Peninsula and the Petén region of Guatemala were more genetically similar to each other than to fish from nearby sites and movement of Mayan Cichlids between these regions occurred thousands of generations ago, suggestive of pre-Columbian human transportation of Mayan Cichlids through this region. Mayan Cichlids present a rare example of cytonuclear disequilibrium and reduced genetic diversity in the introduced population that persists more than 30 years (at least 7-8 generations after introduction. We suggest that hybridization occurred in ornamental fish farms in Florida and may contribute their establishment in the novel habitat. Hybridization prior to release may contribute to other successful invasions.

  3. Genetic evidence for multiple sources of the non-native fish Cichlasoma urophthalmus (Günther; Mayan Cichlids) in southern Florida.

    Science.gov (United States)

    Harrison, Elizabeth; Trexler, Joel C; Collins, Timothy M; Vazquez-Domínguez, Ella; Razo-Mendivil, Ulises; Matamoros, Wilfredo A; Barrientos, Christian

    2014-01-01

    The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid). Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids from the upper Yucatán Peninsula to Guatemala and introductions from Guatemala and Belize to Florida. The mismatch between mitochondrial and nuclear genomes suggests admixture of a female lineage from Guatemala, where all individuals were fixed for the mitochondrial haplotype found in the introduced population, and a more diverse but also relatively small number of individuals from Belize. The Florida cytochrome b haplotype appears to be absent from Belize (0 out of 136 fish screened from Belize had this haplotype). Genetic structure within the Florida population was minimal, indicating a panmictic population, while Mexican and Central American samples displayed more genetic subdivision. Individuals from the Upper Yucatán Peninsula and the Petén region of Guatemala were more genetically similar to each other than to fish from nearby sites and movement of Mayan Cichlids between these regions occurred thousands of generations ago, suggestive of pre-Columbian human transportation of Mayan Cichlids through this region. Mayan Cichlids present a rare example of cytonuclear disequilibrium and reduced genetic diversity in the introduced population that persists more than 30 years (at least 7-8 generations) after introduction. We suggest that hybridization occurred in ornamental fish farms in Florida and may contribute their establishment in the novel habitat. Hybridization prior to release may contribute to other successful invasions.

  4. Discovery of the invasive Mayan Cichlid fish "Cichlasoma" urophthalmus (Günther 1862) in Thailand, with comments on other introductions and potential impacts

    Science.gov (United States)

    Nico, Leo G.; Beamish, William H.; Musikasinthorn, Prachya

    2007-01-01

    We report on the occurrence and possible establishment of a non-native cichlid fish in a brackish-water system in the lower Chao Phraya River delta region, Thailand. Although, the possibility of some degree of introgressive hybridization can not be ruled out, Thailand specimens agree best with Mayan Cichlid “Cichlasoma” urophthalmus (Günther 1862). Our collections represent the first records of this New World, highly-invasive, euryhaline fish from Thailand and coincides with recent collections from Singapore. Positive identification of specimens as “C.” urophthalmus requires caution due to the diversity of the Cichlidae (>1,300 species), widespread introduction of many family members, variation within species, extensive interspecific overlap in characters, and proliferation of artificial cichlid hybrids (e.g., Flowerhorns). We first became aware of the Thailand population in 2005 when “C.” urophthalmus began appearing in the catches of local fishermen. We visited the site in November 2006 and obtained and examined voucher specimens. The abundance and wide size range of juveniles and adults in local ponds and an adjacent canal is evidence of natural reproduction. Because water bodies throughout the Chao Phraya delta are interconnected and subject to flooding, it is likely that “C.” urophthalmus is already established and is dispersing, but surveys and monitoring are needed to determine their exact geographic range. The Thailand population is compared to “C.” urophthalmus introduced into Florida (USA). Based on what is known about Florida “C.” urophthalmus, it is predicted that this cichlid will further invade coastal and inland waters in Thailand and elsewhere in Southeast Asia. This cichlid has a long history in the aquarium trade in Europe. However, there are no records from the wild in European waters and, because of the colder climate, the possibility of establishment in that region is relatively low.

  5. Assessment of spatial rainfall variability in Lake Victoria Basin

    Science.gov (United States)

    Kizza, M.; Westerberg, I.; Rodhe, A.; Ntale, H. K.

    2011-12-01

    A gridded monthly rainfall dataset having a spatial resolution of 2 km and covering the period 1960-2004 was derived for the Lake Victoria basin. Such a dataset is useful for hydrological modelling aimed at resource utilisation and for estimation of catchment inflow to Lake Victoria. The lake and its basin support more than 30 million people and also contribute substantially to the River Nile flow. The major challenge in analysing the lake water balance is the estimation of the rainfall over the lake which is complicated by the varying quality and spatial coverage of rain-gauge data in the basin. In this study we addressed these problems by using satellite-derived precipitation data from two products and rain-gauge data for 362 stations around the basin to derive a monthly precipitation dataset for the entire basin, including the lake. First, the rain-gauge data were quality controlled; resulting in a rejection of 13% of the stations while 12% needed corrective actions. These results emphasise the importance of a systematic quality control of rain-guage data in this region. Thereafter we filled short gaps in the daily data series which resulted in 9,429 additional months of data. Two interpolation methods were then assessed for spatial interpolation and the universal kriging method performed slightly better than the inverse distance weighting method. The rainfall patterns in the interpolated dataset were shown to be consistent with the spatial and temporal patterns expected at the large scale as a result of the climate variability in the basin. The key problem of how to account for the enhancement of rainfall over the lake surface because of the lake-land thermal contrasts was addressed by estimating a relationship between rain-gauge and satellite data. Two satellite rainfall products, TRMM 3B43 and PERSIANN were compared to the interpolated monthly rain-gauge data for the land part of the basin. The bias in the TRMM 3B43 rainfall estimates was higher than the bias

  6. Stratigraphic relations of australites in the Port Campbell embayment, Victoria

    Science.gov (United States)

    Shoemaker, Eugene M.; Uhlherr, H. Ralph

    1999-05-01

    In the Port Campbell Embayment of Victoria, australites have been found in situ in channel deposits of the Hanson Plain Sand of Pliocene and Pleistocene age. The large majority of the australites, however, occur as a lag deposit at the basal contact of the Sturgess Sand of late Pleistocene and Holocene age and are spatially correlated with ferruginous sandstone clasts that are derived from the Hanson Plain Sand. Some of the tektites are imbedded in or bonded to the ferruginous sandstone clasts, but most are found as individual tektite fragments. A few percent of the tektites have nearly perfectly preserved, complete aerodynamically shaped forms. The sandstone clasts and associated tektites have been reworked from the much older underlying Hanson Plain and have been locally concentrated in the lag deposit. Some tektites also occur at higher levels in the Sturgess Sand, almost invariably in association with stone flakes, exotic stones transported by the aborigines, and, locally, with middens of mollusc shells. Circumstantial evidence indicates that the aborigines transported the tektites found in the upper part of the Sturgess, particularly at Stanhope Bay. As Port Campbell australites unequivocally occur in strata much older than the late Pleistocene and Holocene Sturgess, there is no longer any conflict between the apparent stratigraphic age of the tektites and the middle Pleistocene ages obtained by various chronometric methods.

  7. The bone microstructure of polar "hypsilophodontid" dinosaurs from Victoria, Australia.

    Science.gov (United States)

    Woodward, Holly N; Rich, Thomas H; Vickers-Rich, Patricia

    2018-01-18

    High-latitude (i.e., "polar") Mesozoic fauna endured months of twilight and relatively low mean annual temperatures. Yet non-avian dinosaurs flourished in this taxing environment. Fossils of basal ornithopod dinosaurs ("hypsilophodontids") are common in the Early Cretaceous high-latitude sediments of Victoria, Australia, and four taxa have been described; although their ontogenetic histories are largely unexplored. In the present study, eighteen tibiae and femora were utilized in the first multi-specimen ontogenetic histological analysis of Australian polar hypsilophodontids. The sample consists of eleven individuals from the Flat Rocks locality (Late Valanginian or Barremian), and five from the Dinosaur Cove locality (Albian). In both groups, growth was most rapid during the first three years, and skeletal maturity occurred between five and seven years. There is a weak asymptotic trend in a plot of growth mark count versus femur length, with considerable individual variation. Histology suggests two genera are present within the Dinosaur Cove sample, but bone microstructure alone could not distinguish genera within the Flat Rocks sample, or across the two geologically separate (~ 26 Ma) localities. Additional histologic sampling, combined with morphological analyses, may facilitate further differentiation between ontogenetic, individual, and species variation.

  8. Diversity of soil yeasts isolated from South Victoria Land, Antarctica

    Science.gov (United States)

    Connell, L.; Redman, R.; Craig, S.; Scorzetti, G.; Iszard, M.; Rodriguez, R.

    2008-01-01

    Unicellular fungi, commonly referred to as yeasts, were found to be components of the culturable soil fungal population in Taylor Valley, Mt. Discovery, Wright Valley, and two mountain peaks of South Victoria Land, Antarctica. Samples were taken from sites spanning a diversity of soil habitats that were not directly associated with vertebrate activity. A large proportion of yeasts isolated in this study were basidiomycetous species (89%), of which 43% may represent undescribed species, demonstrating that culturable yeasts remain incompletely described in these polar desert soils. Cryptococcus species represented the most often isolated genus (33%) followed by Leucosporidium (22%). Principle component analysis and multiple linear regression using stepwise selection was used to model the relation between abiotic variables (principle component 1 and principle component 2 scores) and yeast biodiversity (the number of species present at a given site). These analyses identified soil pH and electrical conductivity as significant predictors of yeast biodiversity. Species-specific PCR primers were designed to rapidly discriminate among the Dioszegia and Leucosporidium species collected in this study. ?? 2008 Springer Science+Business Media, LLC.

  9. Flow structures and fluid transport for the hydromedusae Sarsia tubulosa and Aequorea victoria.

    Science.gov (United States)

    Lipinski, Doug; Mohseni, Kamran

    2009-08-01

    The flow structures produced by the hydromedusae Sarsia tubulosa and Aequorea victoria are examined using direct numerical simulation and Lagrangian coherent structures (LCS). Body motion of each hydromedusa is digitized and input to a CFD program. Sarsia tubulosa uses a jetting type of propulsion, emitting a single, strong, fast-moving vortex ring during each swimming cycle while a secondary vortex of opposite rotation remains trapped within the subumbrellar region. The ejected vortex is highly energetic and moves away from the hydromedusa very rapidly. Conversely, A. victoria, a paddling type hydromedusa, is found to draw fluid from the upper bell surface and eject this fluid in pairs of counter-rotating, slow-moving vortices near the bell margins. Unlike S. tubulosa, both vortices are ejected during the swimming cycle of A. victoria and linger in the tentacle region. In fact, we find that A. victoria and S. tubulosa swim with Strouhal numbers of 1.1 and 0.1, respectively. This means that vortices produced by A. victoria remain in the tentacle region roughly 10 times as long as those produced by S. tubulosa, which presents an excellent feeding opportunity during swimming for A. victoria. Finally, we examine the pressure on the interior bell surface of both hydromedusae and the velocity profile in the wake. We find that S. tubulosa produces very uniform pressure on the interior of the bell as well as a very uniform jet velocity across the velar opening. This type of swimming can be well approximated by a slug model, but A. victoria creates more complicated pressure and velocity profiles. We are also able to estimate the power output of S. tubulosa and find good agreement with other hydromedusan power outputs. All results are based on numerical simulations of the swimming jellyfish.

  10. Photoperiod modulation of aggressive behavior is independent of androgens in a tropical cichlid fish.

    Science.gov (United States)

    Gonçalves-de-Freitas, Eliane; Carvalho, Thaís Billalba; Oliveira, Rui F

    2014-10-01

    Photoperiod is a major environmental cue that signals breeding conditions in animals living in temperate climates. Therefore, the activity of the reproductive (i.e. hypothalamic-pituitary-gonadal, HPG) axis and of the expression of reproductive behaviors, including territoriality, is responsive to changes in day length. However, at low latitudes the seasonal variation in day length decreases dramatically and photoperiod becomes less reliable as a breeding entraining cue in tropical species. In spite of this, some tropical mammals and birds have been found to still respond to small amplitude changes in photoperiod (e.g. 17min). Here we tested the effect of 2 photoperiod regimes, referred to as long-day (LD: 16L:08D) and short-day (SD: 08L:16D), on the activity of the HPG axis, on aggressive behavior and in the androgen response to social challenges in males of the tropical cichlid fish Tilapia rendalli. For each treatment, fish were transferred from a pre-treatment photoperiod of 12L:12D to their treatment photoperiod (either LD or SD) in which they were kept for 20days on stock tanks. Afterwards, males were isolated for 4days in glass aquaria in order to establish territories and initial androgen levels (testosterone, T; 11-ketotestosterone, KT) were assessed. On the 4th day, territorial intrusions were promoted such that 1/3 of the isolated males acted as residents and another 1/3 as intruders. Territorial intrusions lasted for 1h to test the effects of a social challenge under different photoperiod regimes. Photoperiod treatment (either SD or LD) failed to induce significant changes in the HPG activity, as measured by androgen levels and gonadosomatic index. However, SD increased the intensity of aggressive behaviors and shortened the time to settle a dominance hierarchy in an androgen-independent manner. The androgen responsiveness to the simulated territorial intrusion was only present in KT but not for T. The percent change in KT levels in response to the

  11. Alternative reproductive tactics in snail shell-brooding cichlids diverge in energy reserve allocation

    Science.gov (United States)

    von Kuerthy, Corinna; Tschirren, Linda; Taborsky, Michael

    2015-01-01

    Life history theory predicts that the amount of resources allocated to reproduction should maximize an individual's lifetime reproductive success. So far, resource allocation in reproduction has been studied mainly in females. Intraspecific variation of endogenous energy storage and utilization patterns of males has received little attention, although these patterns may vary greatly between individuals pursuing alternative reproductive tactics (ARTs). ARTs are characterized by systematic variation of behavioral, physiological, and often morphological traits among same-sex conspecifics. Some individuals may rely on previously accumulated reserves, because of limited foraging opportunities during reproduction. Others may be able to continue foraging during reproduction, thus relying on reserves to a lesser extent. We therefore predicted that, if male tactics involve such divergent limitations and trade-offs within a species, ARTs should correspondingly differ in energy reserve allocation and utilization. To test this prediction, we studied short-term and long-term reserve storage patterns of males in the shell-brooding cichlid Lamprologus callipterus. In this species, bourgeois males investing in territory defense, courtship, and guarding of broods coexist with two distinct parasitic male tactics: (1) opportunistic sneaker males attempting to fertilize eggs by releasing sperm into the shell opening when a female is spawning; and (2) specialized dwarf males attempting to enter the shell past the spawning female to fertilize eggs from inside the shell. Sneaker males differed from other male types by showing the highest amount of accumulated short-term and long-term fat stores, apparently anticipating their upcoming adoption of the nest male status. In contrast, nest males depleted previously accumulated energy reserves with increasing nest holding period, as they invest heavily into costly reproductive behaviors while not taking up any food. This conforms to a capital

  12. Characterising groundwater dynamics in Western Victoria, Australia using Menyanthes software

    Science.gov (United States)

    Woldeyohannes, Yohannes; Webb, John

    2010-05-01

    Water table across much of the western Victoria, Australia have been declining for at least the last 10-15 years, and this is attributed to the consistently low rainfall for these years, but over the same period of time there has been substantial change in land use, with grazing land replaced by cropping and tree plantations appearing in some areas. Hence, it is important to determine the relative effect the climate and land use factors on the water table changes. Monitoring changes in groundwater levels to climate variables and/or land use change is helpful in indicating the degree of threat faced to agricultural and public assets. The dynamics of the groundwater system in the western Victoria, mainly on the basalt plain, have been modelled to determine the climatic influence in water table fluctuations. In this study, a standardized computer package Menyanthes was used for quantifying the influence of climatic variables on the groundwater level, statistically estimating trends in groundwater levels and identify the properties that determine the dynamics of groundwater system. This method is optimized for use on hydrological problems and is based on the use of continuous time transfer function noise model, which estimates the Impulse response function of the system from the temporal correlation between time series of groundwater level and precipitation surplus. In this approach, the spatial differences in the groundwater system are determined by the system properties, while temporal variation is driven by the dynamics of the input into the system. 80 time series models are analysed and the model output parameter values characterized by their moments. The zero-order moment Mo of a distribution function is its area and M1 is related to the mean of the impulse response function. The relation is M1/Mo. It is a measure of the system's memory. It takes approximately 3 times the mean time (M1/Mo) for the effect of a shower to disappear completely from the system. Overall

  13. Evaluation of vehicle side airbag effectiveness in Victoria, Australia.

    Science.gov (United States)

    D'Elia, Angelo; Newstead, Stuart; Scully, Jim

    2013-05-01

    Side airbag systems were first introduced into vehicles around 1995 to help protect occupants from injury in side impact crashes. International studies have shown that side airbags are effective in reducing the risk of death and injury, however, serious injuries can still occur even when side airbags deploy. The objective of this study was to use detailed injury information from insurance injury compensation claims data linked to Police reported crash data to determine the effectiveness of side airbags in reducing the risk of death or injury for occupants involved in side impact crashes in Victoria, Australia based on the specific body regions that side airbag systems are designed to protect. It was found that head and torso-protecting dual airbag systems designed to protect the head, neck, face, chest and abdomen are highly effective in reducing driver death or injury due to near side crashes. They were associated with a statistically significant reduction of 41.1% (25.9%, 53.2%) in the odds of death or injury across all body regions; and a 48.0% (28.0%, 62.4%) reduction in the odds of death or injury to the head, neck, face, chest and abdomen. The study did not find any evidence that torso-protecting airbags alone are effective in reducing death or injury. Analysis results indicate that head and torso-protecting side airbag systems in vehicles are a highly effective technology for reducing the risk of death or injury to vehicle occupants in near side crashes. The magnitude of the injury reduction benefits estimated indicate that fitment of this technology to all vehicles should be a high priority and will yield significant savings in overall road trauma. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Capillaria (Hepatocapillaria) cichlasomae (Nematoda: Capillariidae) from the liver of the cichlid fish Cichlasoma urophthalmus from Yucatan, Mexico.

    Science.gov (United States)

    Moravec, F; Scholz, T; Mendoza Franco, E

    1995-01-01

    Capillaria (Hepatocapillaria) cichlasomae sp. n., parasitic in the liver of the cichlid Cichlasoma urophthalmus (Günther) from a small freshwater lake ("aguada") Xpoc in Yucatan, Mexico, is described. The parasite is characterized mainly by its small body size (male 1.8 mm, female 4.5 mm), the structure of the stichosome (markedly short stichocytes in one row) and the male (the presence of a pair of small subventral postanal papillae) and female (anus distinctly subterminal) caudal ends, and by the size and structure of the spicule (spicule 0.068-0.085 mm long, with marked transverse grooves on surface) and eggs (size 0.053-0.058 x 0.023 mm, with protruding polar plugs). This is the second known Capillaria species from the liver of fish and the first one from the liver of a freshwater fish.

  15. Salinity effects on behavioural response to hypoxia in the non-native Mayan cichlid Cichlasoma urophthalmus from Florida Everglades wetlands

    Science.gov (United States)

    Schofield, P.J.; Loftus, W.F.; Fontaine, J.A.

    2009-01-01

    This study quantified the hypoxia tolerance of the Mayan cichlid Cichlasoma urophthalmus over a range of salinities. The species was very tolerant of hypoxia, using aquatic surface respiration (ASR) and buccal bubble holding when oxygen tensions dropped to <20 mmHg (c. 1??0 mg l-1) and 6 mmHg, respectively. Salinity had little effect on the hypoxia tolerance of C. urophthalmus, except that bubble holding was more frequent at the higher salinities tested. Levels of aggression were greatest at the highest salinity. The ASR thresholds of C. urophthalmus were similar to native centrarchid sunfishes from the Everglades, however, aggression levels for C. uropthalmus were markedly higher. ?? 2009 The Fisheries Society of the British Isles.

  16. The first record of the invasive Asian fish tapeworm (Schyzocotyle acheilognathi from an endemic cichlid fish in Madagascar

    Directory of Open Access Journals (Sweden)

    Scholz T.

    2018-03-01

    Full Text Available The Asian fish tapeworm, Schyzocotyle acheilognathi (Yamaguti, 1934 (Cestoda: Bothriocephalidea, is an invasive parasite of freshwater fishes that have been reported from more than 200 freshwater fish worldwide. It was originally described from a small cyprinid, Acheilognathus rombeus, in Japan but then has spread, usually with carp, minnows or guppies, to all continents including isolated islands such as Hawaii, Puerto Rico, Cuba or Sri Lanka. In the present account, we report the first case of the infection of a native cichlid fish, Ptychochromis cf. inornatus (Perciformes: Cichlidae, endemic to Madagascar, with S. acheilognathi. The way of introduction of this parasite to the island, which is one of the world’s biodiversity hotspots, is briefly discussed.

  17. Diet and food consumption of the pearl cichlid Geophagus brasiliensis (Teleostei: Cichlidae: relationships with gender and sexual maturity

    Directory of Open Access Journals (Sweden)

    Rodrigo F. Bastos

    Full Text Available Despite the importance of the pearl cichlid Geophagus brasiliensis for the aquarium fish trade worldwide and its wide distribution, many aspects of its biology, such as the relationships between its feeding ecology and reproductive behavior, are not fully understood in natural conditions on its native habitat. In this paper, we investigated its diet focusing on how differences in diet and food consumption are related to differences in gender and sexual maturity. The digestive tract of each individual was dissected and had its content analyzed, whereas each gonad was microscopically analyzed to determine gender (male/female and sexual maturity (immature/mature. A total of 28 females and 31 males were analyzed. Mature individuals were more common than immature specimens both for males (64.50% and females (64.30%. The analysis of 52 individuals with non-empty digestive tracts revealed a diet comprised of 27 items. According to the Index of Alimentary importance (%IAi, the most important food items in the diet were Gastropoda (37.30%, fragments of vascular plants (15.16%, detritus (10.14%, Amphipoda (9.24%, and fish scales (6.29%. Mature males had more empty stomachs (65.00% when compared to immature males (27.27% and immature (55.56% and mature females (40.00%. Also, mature females seemed to have more food consumption (greater mean values of total volume in their digestive tracts than mature males. Some hypotheses are proposed in order to distinguish if this gender-based difference in food consumption in mature individuals of the pearl cichlid could be associated with the development of primary and secondary sexual characteristics or with asymmetrical time invested in parental care activities.

  18. Marine research in the Latitudinal Gradient Project along Victoria Land, Antarctica

    Directory of Open Access Journals (Sweden)

    Paul Arthur Berkman

    2005-12-01

    Full Text Available This paper describes the conceptual framework of the Latitudinal Gradient Project that is being implemented by the New Zealand, Italian and United States Antarctic programmes along Victoria Land, Antarctica, from 72°S to 86°S. The purpose of this interdisciplinary research project is to assess the dynamics and coupling of marine and terrestrial ecosystems in relation to global climate variability. Preliminary data about the research cruises from the R/V “Italica” and R/V “Tangaroa” along the Victoria Land Coast in 2004 are presented. As a global climate barometer, this research along Victoria Land provides a unique framework for assessing latitudinal shifts in ‘sentinel’ environmental transition zones, where climate changes have an amplified impact on the phases of water.

  19. Chemodenitrification in the cryoecosystem of Lake Vida, Victoria Valley, Antarctica.

    Science.gov (United States)

    Ostrom, N E; Gandhi, H; Trubl, G; Murray, A E

    2016-11-01

    Lake Vida, in the Victoria Valley of East Antarctica, is frozen, yet harbors liquid brine (~20% salt, >6 times seawater) intercalated in the ice below 16 m. The brine has been isolated from the surface for several thousand years. The brine conditions (permanently dark, -13.4 °C, lack of O2 , and pH of 6.2) and geochemistry are highly unusual. For example, nitrous oxide (N2 O) is present at a concentration among the highest reported for an aquatic environment. Only a minor 17 O anomaly was observed in N2 O, indicating that this gas was predominantly formed in the lake. In contrast, the 17 O anomaly in nitrate (NO3-) in Lake Vida brine indicates that approximately half or more of the NO3- present is derived from atmospheric deposition. Lake Vida brine was incubated in the presence of 15 N-enriched substrates for 40 days. We did not detect microbial nitrification, dissimilatory reduction of NO3- to ammonium (NH4+), anaerobic ammonium oxidation, or denitrification of N2 O under the conditions tested. In the presence of 15 N-enriched nitrite (NO2-), both N2 and N2 O exhibited substantial 15 N enrichments; however, isotopic enrichment declined with time, which is unexpected. Additions of 15 N-NO2- alone and in the presence of HgCl2 and ZnCl2 to aged brine at -13 °C resulted in linear increases in the δ15 N of N2 O with time. As HgCl2 and ZnCl2 are effective biocides, we interpret N2 O production in the aged brine to be the result of chemodenitrification. With this understanding, we interpret our results from the field incubations as the result of chemodenitrification stimulated by the addition of 15 N-enriched NO2- and ZnCl2 and determined rates of N2 O and N2 production of 4.11-41.18 and 0.55-1.75 nmol L-1  day-1 , respectively. If these rates are representative of natural production, the current concentration of N2 O in Lake Vida could have been reached between 6 and 465 years. Thus, chemodenitrification alone is sufficient to explain the high levels of N2 O

  20. Stroke Incidence in Victoria, Australia—Emerging Improvements

    Directory of Open Access Journals (Sweden)

    Benjamin B. Clissold

    2017-05-01

    Full Text Available BackgroundEvidence of a decline in the incidence of stroke has emerged from population-based studies. These have included retrospective and prospective cohorts. However, in Australia and other countries, government bodies and stroke foundations predict a rise in the prevalence of stroke that is anticipated to increase the burden of stroke across the entire domain of care. This increase in prevalence must be viewed as different from the decline in incidence being observed, a measure of new stroke cases. In Victoria, all public emergency department visits and public and private hospital admissions are reported to the Department of Health and Human Services and include demographic, diagnostic, and procedural/treatment information.MethodsWe obtained data from financial years 1997/1998 to 2007/2008 inclusive, for all cases with a primary stroke diagnosis (ICD-10-AM categories with associated data fields. Incident cases were established by using a 5-year clearance period.ResultsFrom 2003/2004 to 2007/2008 inclusive, there were 53,425 patients with a primary stroke or TIA diagnosis. The crude incident stroke rate for first ever stroke was 211 per 100,000 per year (95% CI 205–217 [females—205 per 100,000 per year (95% CI 196–214 and males—217 per 100,000 per year (95% CI 210–224]. The overall stroke rates were seen to significantly decline over the period [males (per 100,000 per year 227 in 2003/2004 to 202 in 2007/2008 (p = 0.0157 and females (per 100,000 per year 214 in 2003/2004 to 188 in 2007/2008 (p = 0.0482]. Ischemic stroke rates also appeared to decline; however, this change was not significant.ConclusionThese results demonstrate a significant decline in stroke incidence during the study period and may suggest evidence for effectiveness of primary and secondary prevention strategies in cerebrovascular risk factor management.

  1. One Fish, Two Fish, Red Fish, Blue Fish: Geography, Ecology, Sympatry, and Male Coloration in the Lake Malawi Cichlid Genus Labeotropheus (Perciformes: Cichlidae)

    OpenAIRE

    Pauers, Michael J.

    2011-01-01

    While sexual selection on male coloration has been important in haplochromine cichlid speciation, few studies to date have examined potential environmental influences on color pattern evolution. Data from multiple sources on male nuptial coloration of the Lake Malawi endemic genus Labeotropheus were used to examine the relationship between color patterns and the environments in which these patterns were found. Red- or carotenoid-pigmented males were concentrated in the northwestern portion of...

  2. A new fossil cichlid from the Middle Miocene in the East African Rift Valley (Tugen Hills, Central Kenya: First record of a putative Ectodini

    Directory of Open Access Journals (Sweden)

    Melanie Altner

    2015-11-01

    Full Text Available Identification of fossil cichlids is difficult, because the currently used diagnostic morphological characters for living cichlids are mostly soft tissue based and such characters are hardly preserved in fossils. During our recent fieldwork in the Central Kenya Rift (E-Africa, we discovered several exceptionally well-preserved fossil cichlids, which can be assigned to different lineages among the African Pseudocrenilabrinae. Here we present one of those new specimens. Its most conspicuous character is a lateral line divided into three segments. This specimen was found in the lacustrine sediments of the Middle Miocene site Waril, Tugen Hills, Kenya. The site represents the deposits of an ancient freshwater lake ca. 9-10 million years ago. Previous work on fossil leaves from the same site allow for the reconstruction of open vegetation surrounding the lake and pronounced dry seasons. Among the main further characteristics of the new fossil cichlid is a lachrimal with six lateral line canals, big cycloid scales and a low number of dorsal fin spines (XIII. The latter two characters are traceable in several members of tribes within the Pseudocrenilabrinae. However, a lachrimal with six lateral line canals is exclusively found in certain tribes of the EAR (East African Radiation within the Pseudocrenilabrinae. Moreover, the unique lateral line pattern is solely present in two genera of the EAR tribe Ectodini. However, the fossil shows cycloid scales, while modern Ectodini have ctenoid scales. Taken all evidence together, this fossil may perhaps represent an ancient lineage related to the Ectodini. Up to date, there is no definite fossil record of the members of the EAR. Our fossil may represent the first reliable calibration point for this group, which would be consistent with the previously reconstructed diversification time of the H-lineage (EAR tribes, except Boulengerochromini, Bathybatini, Trematocarini and Lamprologini and the Lamprologini ca

  3. Quantitative Genetic Analyses of Male Color Pattern and Female Mate Choice in a Pair of Cichlid Fishes of Lake Malawi, East Africa

    Science.gov (United States)

    Ding, Baoqing; Daugherty, Daniel W.; Husemann, Martin; Chen, Ming; Howe, Aimee E.; Danley, Patrick D.

    2014-01-01

    The traits involved in sexual selection, such as male secondary sexual characteristics and female mate choice, often co-evolve which can promote population differentiation. However, the genetic architecture of these phenotypes can influence their evolvability and thereby affect the divergence of species. The extraordinary diversity of East African cichlid fishes is often attributed to strong sexual selection and thus this system provides an excellent model to test predictions regarding the genetic architecture of sexually selected traits that contribute to reproductive isolation. In particular, theory predicts that rapid speciation is facilitated when male sexual traits and female mating preferences are controlled by a limited number of linked genes. However, few studies have examined the genetic basis of male secondary sexual traits and female mating preferences in cichlids and none have investigated the genetic architecture of both jointly. In this study, we artificially hybridized a pair of behaviorally isolated cichlid fishes from Lake Malawi and quantified both melanistic color pattern and female mate choice. We investigated the genetic architecture of both phenotypes using quantitative genetic analyses. Our results suggest that 1) many non-additively acting genetic factors influence melanistic color patterns, 2) female mate choice may be controlled by a minimum of 1–2 non-additive genetic factors, and 3) F2 female mate choice is not influenced by male courting effort. Furthermore, a joint analysis of color pattern and female mate choice indicates that the genes underlying these two traits are unlikely to be physically linked. These results suggest that reproductive isolation may evolve rapidly owing to the few genetic factors underlying female mate choice. Hence, female mate choice likely played an important role in the unparalleled speciation of East African cichlid fish. PMID:25494046

  4. Stratigraphic architecture of bedrock reference section, Victoria Crater, Meridiani Planum, Mars

    Science.gov (United States)

    Edgar, Lauren A.; Grotzinger, John P.; Hayes, Alex G.; Rubin, David M.; Squyres, Steve W.; Bell, James F.; Herkenhoff, Ken E.

    2012-01-01

    The Mars Exploration Rover Opportunity has investigated bedrock outcrops exposed in several craters at Meridiani Planum, Mars, in an effort to better understand the role of surface processes in its geologic history. Opportunity has recently completed its observations of Victoria crater, which is 750 m in diameter and exposes cliffs up to ~15 m high. The plains surrounding Victoria crater are ~10 m higher in elevation than those surrounding the previously explored Endurance crater, indicating that the Victoria crater exposes a stratigraphically higher section than does the Endurance crater; however, Victoria strata overlap in elevation with the rocks exposed at the Erebus crater. Victoria crater has a well-developed geomorphic pattern of promontories and embayments that define the crater wall and that reveal thick bedsets (3–7m) of large-scale cross-bedding, interpreted as fossil eolian dunes. Opportunity was able to drive into the crater at Duck Bay, located on the western margin of Victoria crater. Data from the Microscopic Imager and Panoramic Camera reveal details about the structures, textures, and depositional and diagenetic events that influenced the Victoria bedrock. A lithostratigraphic subdivision of bedrock units was enabled by the presence of a light-toned band that lines much of the upper rim of the crater. In ascending order, three stratigraphic units are named Lyell, Smith, and Steno; Smith is the light-toned band. In the Reference Section exposed along the ingress path at Duck Bay, Smith is interpreted to represent a zone of diagenetic recrystallization; however, its upper contact also coincides with a primary erosional surface. Elsewhere in the crater the diagenetic band crosscuts the physical stratigraphy. Correlation with strata present at nearby promontory Cape Verde indicates that there is an erosional surface at the base of the cliff face that corresponds to the erosional contact below Steno. The erosional contact at the base of Cape Verde

  5. Archiving the Web: A Case Study from the University of Victoria

    Directory of Open Access Journals (Sweden)

    Corey Davis

    2014-10-01

    Full Text Available The University of Victoria Libraries started archiving websites in 2013, and it quickly became apparent that many scholarly websites being produced by faculty, especially in the digital humanities, were going to prove very challenging to effectively capture and play back. This article will provide an overview of web archiving and explore the considerable legal and technical challenges of implementing a web archiving initiative at a research library, using the University of Victoria's implementation of Archive-it, a web archiving service from the Internet Archive, as a case study, with a special focus on capturing complex, interactive websites that scholars are creating to disseminate their research in new ways.

  6. Discordant genetic diversity and geographic patterns between Crassicutis cichlasomae (Digenea: Apocreadiidae) and its cichlid host, "Cichlasoma" urophthalmus (Osteichthyes: Cichlidae), in Middle-America.

    Science.gov (United States)

    Razo-Mendivil, Ulises; Vázquez-Domínguez, Ella; de León, Gerardo Pérez-Ponce

    2013-12-01

    Genetic analyses of hosts and their parasites are key to understand the evolutionary patterns and processes that have shaped host-parasite associations. We evaluated the genetic structure of the digenean Crassicutis cichlasomae and its most common host, the Mayan cichlid "Cichlasoma" urophthalmus, encompassing most of their geographical range in Middle-America (river basins in southeastern Mexico, Belize, and Guatemala together with the Yucatan Peninsula). Genetic diversity and structure analyses were done based on 167 cytochrome c oxidase subunit 1 sequences (330 bp) for C. cichlasomae from 21 populations and 161 cytochrome b sequences (599 bp) for "C." urophthalmus from 26 populations. Analyses performed included phylogenetic tree estimation under Bayesian inference and maximum likelihood analysis, genetic diversity, distance and structure estimates, haplotype networks, and demographic evaluations. Crassicutis cichlasomae showed high genetic diversity values and genetic structuring, corresponding with 4 groups clearly differentiated and highly divergent. Conversely, "C." urophthalmus showed low levels of genetic diversity and genetic differentiation, defined as 2 groups with low divergence and with no correspondence with geographical distribution. Our results show that species of cichlids parasitized by C. cichlasomae other than "C." urophthalmus, along with multiple colonization events and subsequent isolation in different basins, are likely factors that shaped the genetic structure of the parasite. Meanwhile, historical long-distance dispersal and drought periods during the Holocene, with significant population size reductions and fragmentations, are factors that could have shaped the genetic structure of the Mayan cichlid.

  7. The mechanosensory lateral line is used to assess opponents and mediate aggressive behaviors during territorial interactions in an African cichlid fish.

    Science.gov (United States)

    Butler, Julie M; Maruska, Karen P

    2015-10-01

    Fish must integrate information from multiple sensory systems to mediate adaptive behaviors. Visual, acoustic and chemosensory cues provide contextual information during social interactions, but the role of mechanosensory signals detected by the lateral line system during aggressive behaviors is unknown. The aim of this study was first to characterize the lateral line system of the African cichlid fish Astatotilapia burtoni and second to determine the role of mechanoreception during agonistic interactions. The A. burtoni lateral line system is similar to that of many other cichlid fishes, containing lines of superficial neuromasts on the head, trunk and caudal fin, and narrow canals. Astatotilapia burtoni males defend their territories from other males using aggressive behaviors that we classified as non-contact or contact. By chemically and physically ablating the lateral line system prior to forced territorial interactions, we showed that the lateral line system is necessary for mutual assessment of opponents and the use of non-contact fight behaviors. Our data suggest that the lateral line system facilitates the use of non-contact assessment and fight behaviors as a protective mechanism against physical damage. In addition to a role in prey detection, the diversity of lateral line morphology in cichlids may have also enabled the expansion of their social behavioral repertoire. To our knowledge, this is the first study to implicate the lateral line system as a mode of social communication necessary for assessment during agonistic interactions. © 2015. Published by The Company of Biologists Ltd.

  8. The role of rare morph advantage and conspicuousness in the stable gold-dark colour polymorphism of a crater lake Midas cichlid fish.

    Science.gov (United States)

    Torres-Dowdall, Julián; Golcher-Benavides, Jimena; Machado-Schiaffino, Gonzalo; Meyer, Axel

    2017-09-01

    Genetically based stable colour polymorphisms provide a unique opportunity to study the evolutionary processes that preserve genetic variability in the wild. Different mechanisms are proposed to promote the stability of polymorphisms, but only few empirical examples have been documented, resulting in an incomplete understanding of these mechanisms. A remarkable genetically determined stable colour polymorphism is found in the Nicaraguan Midas cichlid species complex (Amphilophus cf. citrinellus). All Midas cichlids start their life with a dark-grey coloration (dark morph), but individuals carrying the dominant "gold" allele (c. 10%) lose their melanophores later in life, revealing the underlying orange coloration (gold morph). How this polymorphism is maintained remains unclear. Two main hypotheses have been proposed, both suggesting differential predation upon colour morphs as the proximate mechanism. One predicts that the conspicuous gold morph is more likely to be preyed upon, but this disadvantage is balanced by their competitive dominance over the dark morph. The second hypothesis suggests a rare morph advantage where the rarer gold morph experiences less predation. Empirical evidence for either of these mechanisms is still circumstantial and inconclusive. We conducted two field experiments in a Nicaraguan crater lake using wax models simulating both morphs to determine predation pressure upon Midas cichlid colour morphs. First, we tested the interaction of coloration and depth on attack rate. Second, we tested the interaction of fish size and coloration. We contrasted the pattern of attacks from these experiments to the predicted predation patterns from the hypotheses proposed to explain the colour polymorphism's stability. Large models imitating colour morphs were attacked at similar rates irrespectively of their position in the water column. Yet, attacks upon small models resembling juveniles were directed mainly towards dark models. This resulted in a

  9. Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services

    NARCIS (Netherlands)

    Downing, Andrea S.; van Nes, Egbert H.; Balirwa, John S.; Beuving, Joost; Bwathondi, P. O. J.; Chapman, Lauren J.; Cornelissen, Ilse J. M.; Cowx, Iain G.; Goudswaard, Kees P. C.; Hecky, Robert E.; Janse, Jan H.; Janssen, Annette B. G.; Kaufman, Les; Kishe-Machumu, Mary A.; Kolding, Jeppe; Ligtvoet, Willem; Mbabazi, Dismas; Medard, Modesta; Mkumbo, Oliva C.; Mlaponi, Enock; Munyaho, Antony T.; Nagelkerke, Leopold A. J.; Ogutu-Ohwayo, Richard; Ojwang, William O.; Peter, Happy K.; Schindler, Daniel E.; Seehausen, Ole; Sharpe, Diana; Silsbe, Greg M.; Sitoki, Lewis; Tumwebaze, Rhoda; Tweddle, Denis; van de Wolfshaar, Karen E.; van Dijk, Han; van Donk, Ellen; van Rijssel, Jacco C.; van Zwieten, Paul A. M.; Wanink, Jan; Witte, F.; Mooij, Wolf M.

    2014-01-01

    East Africa's Lake Victoria provides resources and services to millions of people on the lake's shores and abroad. In particular, the lake's fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly

  10. The diversity of benthic mollusks of Lake Victoria and Lake Burigi ...

    African Journals Online (AJOL)

    Molluscan diversity, abundance and distribution in sediments of Lake Victoria and its satellite lake, Lake Burigi, were investigated. The survey was carried out ... Melanoides tuberculata and Biomphalaria chaonomphala were the only two gastropods represented and widely distributed in the two lakes. Bivalvia constituting of ...

  11. Connections '98. Proceedings of a Faculty Conference (4th, Victoria, British Columbia, Canada, May 1998).

    Science.gov (United States)

    Gibbons, Sandra L., Ed.; Anderson, John O., Ed.

    This proceedings contains 13 papers from the 1998 annual Faculty of Education conference at the University of Victoria, British Columbia (Canada). The papers are: (1) "Struggling with Re-Presentation, Voice, and Self in Narrative Research" (Marla Arvay); (2) "Women's Soccer in Canada: A Slow Road to Equity" (Meredith Bogle,…

  12. Nile perch fish processing waste along Lake Victoria in East Africa ...

    African Journals Online (AJOL)

    Worldwide, fish industry wastes are an important contaminant having an impact on the environment. The recovery of value added products from these residues constitutes an important waste reduction strategy for the industry. In East Africa, Nile perch fish processing into chilled fish fillet for export along Lake Victoria ...

  13. Water hyacinth hotspots in the Ugandan waters of Lake Victoria in ...

    African Journals Online (AJOL)

    Water hyacinth invaded Lake Victoria in the 1980s and, by 1998, had attained peak coverage of approximately 2 000 ha in the Ugandan waters of the lake. Control interventions, especially via biological means, significantly reduced the weed's coverage to non-nuisance levels (<10 ha) by 1999. Although resurgence was ...

  14. Perception of Aquaculture Education to Support Further Growth of Aquaculture Industry in Victoria, Australia

    Science.gov (United States)

    Awal, Sadiqul; Christie, Andrew; Watson, Matthew; Hannadige, Asanka G. T.

    2012-01-01

    Purpose: The central aim of this study was to determine the perception of aquaculture educational provisions in the state of Victoria, and whether they are sufficient to ultimately support further growth of the industry. Design/methodology/approach: Questionnaires were formulated and distributed to participants in a variety of ways, including via…

  15. Lake Victoria wetlands and the ecology of the Nile tilapia, Oreochromis niloticus Linne

    NARCIS (Netherlands)

    Balirwa, J.S.

    1998-01-01

    An ecological study of wetlands was undertaken in northern Lake Victoria (East Africa) between 1993 and 1996 with a major aim of characterising shallow vegetation-dominated interface habitats, and evaluating their importance for fish, in particular, for the stocked and socio-economically

  16. People Management Practices in the Public Health Sector: Developments from Victoria, Australia

    Science.gov (United States)

    Stanton, Pauline; Bartram, Timothy; Harbridge, Raymond

    2004-01-01

    This study investigates the impact on human resource management (HRM) practices in the public health sector in Victoria, Australia of two different government policy environments. First, it explores the Liberal Coalition Government's decentralisation of public health sector management, from 1992-1999 and second, the Labor Government's…

  17. From Aspiration to Destination: Understanding the Decisions of University Applicants in Regional Victoria

    Science.gov (United States)

    Harvey, Andrew; Burnheim, Catherine; Joschko, Lucie; Luckman, Michael

    2012-01-01

    This paper examines the choices and destinations of prospective university students from three regional areas in Victoria. The study is based on information collected for tertiary applicants in the Gippsland, Bendigo and Mildura areas, all of which host a local university campus. Using application and enrollment data, we examine the choices that…

  18. What Do the Public Search for on the Catalogue of the State Library of Victoria?

    Science.gov (United States)

    Waller, Vivienne

    2009-01-01

    This study examines what the public search for in the catalogue of the State Library of Victoria (SLV). As well as indicating the type of content being accessed, this gives an indication of what catalogue users expect of the State Library collection. A content analysis was undertaken of a random, stratified sample of 4,000 search queries typed in…

  19. Do invasive bullfrogs in Victoria, British Columbia, Canada, show evidence of parasite release?

    Science.gov (United States)

    Dare, O K; Forbes, M R

    2013-06-01

    Few studies have examined vertebrate models of invasive species to explore parasite release as a proposed mechanism through which host species might become invasive. In this study, we examined evidence for parasite release in invasive American bullfrogs (Rana catesbeiana/Lithobates catesbeianus) from five sites in Victoria, British Columbia, Canada. We examined helminth species richness, as well as the prevalence, intensity and abundance of lung and kidney fluke infections. These flukes are expected to impose costs on host survival, growth and reproductive output. We compared measures of these parasite taxa with bullfrogs from Ontario and New Brunswick where they are endemic. Helminth species richness in bullfrogs from the Victoria sites was lower than in Ontario bullfrogs, but comparable to reported indices for other endemic populations. The prevalence of lung flukes (Haematoloechus spp.) in bullfrogs from Victoria was twice as high as was observed in the Ontario bullfrogs, and higher than has been reported from other endemic locations. In four of the five study sites in Victoria, numbers of Echinostoma spp. kidney cysts were lower than observed in endemic populations; however, the fifth site had uncharacteristically high numbers of cysts. In this study, there did not appear to be clear evidence to support parasite release using either parasite species numbers, or infection by specific parasite taxa. Instead, the invasive bullfrogs demonstrated high parasite species richness and high levels of infection for parasites known to be harmful to their hosts.

  20. Lake Victoria wetlands and the ecology of the Nile Tilapia, Oreochromis Niloticus Linné

    NARCIS (Netherlands)

    Balirwa, J.S.

    1998-01-01

    The importance of LalVictoria wetlands for the Nile tilap'a was studied. Five wetland types were defined: papyrus, reed, bulrush, hippo grass, water hyacinth. Hydrology, vegetation and distance towards open water explained the variation in abiotic and biotic factors. Over 30 fish species were

  1. Distribution of Nile perch Lates niloticus in southern Lake Victoria is ...

    African Journals Online (AJOL)

    Although Nile perch Lates niloticus is assumed to be sensitive to low oxygen concentrations, it was found in deep water in Lake Victoria, where oxygen depletion is common during the rainy season. Since factors determining Nile perch distribution are not well understood its spatial distribution in the Mwanza Gulf of Lake ...

  2. affect rice in integrated rice-fish culture in Lake Victoria Basin, Kenya?

    African Journals Online (AJOL)

    AGHOGHO A

    To ensure increased adoption of rice-fish farming, we have to be certain that practices and adoption of these technologies fit within the available resources, the socio-cultural and economic conditions of the Lake. Victoria Basin (LVB). Practices and technologies from. Asia may be inappropriate due to differences in agro cli-.

  3. Monitoring exposure to heavy metals among children in Lake Victoria, Kenya: Environmental and fish matrix

    NARCIS (Netherlands)

    Okoth, E.O.; Admiraal, W.; Osano, O.; Ngure, V.; Kraak, M.H.S.; Omutange, E.S.

    2010-01-01

    This study used hair and nails to biomonitor heavy metals (Pb, Cd, Cr and Cu) from geological source and exposure through regular fish consumption among children in Lake Victoria, Kenya. Concentration of Pb and Cu in water reflected anthropogenic pathways, while Cd and Cr reflected accumulation from

  4. Metal concentrations in sediment and fish of Lake Victoria near and ...

    African Journals Online (AJOL)

    Concentrations of metals in sediment and fish as well as organic matter contents of sediment from Lake Victoria were investigated. The objective of the study was to compare levels of metals in sediment and fish from areas of the lake that are within and outside catchments with gold mining activities. The results showed that ...

  5. Testing the Marine Hypothesis for The Opportunity Landing Site at Victoria Crater

    Science.gov (United States)

    Parker, T. J.

    2006-12-01

    Hypothesis Summary: 1. Meridiani Planum is a marine sulfate platform deposit, analogous to terrestrial carbonate platforms but with sulfate mineralogy, laid down during one or multiple marine transgressions over the landing site region. 2. Outcrop laminations, ripples, and larger, dune-scale bedforms are subaqueous in origin, produced by tidal currents. Aqueous deposits may be interbedded with crossbedded aeolian deposits of same composition derived from subjacent water-lain deposits during lowstands. At the scale of observations made by Opportunity, the marine hypothesis differs from the consensus, sabkha model, in two relatively minor ways (but with important differences in the inferred paleoenvironments). 3. Blueberry and cobble "lag" on top of outcrop is a lag, but indicates erosion of perhaps many meters, even tens of meters or more of outcrop material from the region by water. Wind erosion has been very limited over geologic time (perhaps less than a meter locally). 4. Remarkably-flat, horizontal geomorphic surface of outcrop was produced by shallow standing water locally, controlling both deposition and erosion of the sulfate outcrop material to within a few meters of sea level. 5. Craters in the landing site exhibit a continuum of degradation states, with Endurance and Victoria typifying the best preserved craters visited (or to be visited) by Opportunity, and Erebus and Terra Nova representing the most degraded craters visited that are larger than 100 meters across. Terra Nova is similar to numerous kilometer-scale "rock ring" craters in the Meridiani Planum landing site. 6. "Serrated" rim at Victoria is similar to, but fresher in expression, rim morphology at Erebus Crater, and may indicate water pouring over crater rim during tidal or storm surges in water level across the region. Predictions to be tested at Victoria Crater: 1. The crater's ejecta and raised rim have been destroyed by tidal currents in shallow standing water. There is no Endurance

  6. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    Directory of Open Access Journals (Sweden)

    Guyon Richard

    2012-06-01

    Full Text Available Abstract Background The Nile tilapia (Oreochromis niloticus is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC end sequences and ESTs, but comparative genome analysis and maps of quantitative trait loci (QTL are still limited. Results We have constructed a high-resolution radiation hybrid (RH panel for the Nile tilapia and genotyped 1358 markers consisting of 850 genes, 82 markers corresponding to BAC end sequences, 154 microsatellites and 272 single nucleotide polymorphisms (SNPs. From these, 1296 markers could be associated in 81 RH groups, while 62 were not linked. The total size of the RH map is 34,084 cR3500 and 937,310 kb. It covers 88% of the entire genome with an estimated inter-marker distance of 742 Kb. Mapping of microsatellites enabled integration to the genetic map. We have merged LG8 and LG24 into a single linkage group, and confirmed that LG16-LG21 are also merged. The orientation and association of RH groups to each chromosome and LG was confirmed by chromosomal in situ hybridizations (FISH of 55 BACs. Fifty RH groups were localized on the 22 chromosomes while 31 remained small orphan groups. Synteny relationships were determined between Nile tilapia, stickleback, medaka and pufferfish. Conclusion The RH map and associated FISH map provide a valuable gene-ordered resource for gene mapping and QTL studies. All genetic linkage groups with their corresponding RH groups now have a corresponding chromosome which can be identified in the karyotype. Placement of conserved segments indicated that multiple inter-chromosomal rearrangements have occurred

  7. Soil surface lowering due to soil erosion in villages near Lake Victoria, Uganda

    Science.gov (United States)

    de Meyer, A.; Deckers, J.; Poesen, J.; Isabirye, M.

    2009-04-01

    In the effort to pinpoint the sources of sediment pollution in Lake Victoria, the contribution of sedi-ment from compounds, landing sites, main roads and footpaths is determined in the catchment of Na-bera Bay and Kafunda Bay at the northern shore of Lake Victoria in southern Uganda. The amount of soil loss in compounds and landing sites is determined by the reconstruction of the original and current soil surface according to botanical and man-made datable objects. The soil erosion rate is then deter-mined by dividing the eroded soil volume (corrected for compaction) by the age of the oldest datable object. In the study area, the average soil erosion rate in compounds amounts to 107 Mg ha-1 year-1 (per unit compound) and in landing sites to 207 Mg ha-1 year-1 (per unit landing site). Although com-pounds and landing sites occupy a small area of the study area (1.1 %), they are a major source of sediment to Lake Victoria (63 %). The soil loss on footpaths and main roads is calculated by multip-lying the total length of footpaths and main roads with the average width and depth (measured towards a reference surface). After the correction for compaction is carried out, the soil erosion rate on foot-paths amounts to 34 Mg ha-1 year-1 and on main roads to 35 Mg ha-1 year-1. Also footpaths and main roads occupy a small area of the study area (1.1 %), but contribute disproportionately to the total soil loss in the catchment (22 %). In this research, the information about the village/compound given by the villager/owner is indispensable. In accordance to an adaptation of the model of McHugh et al. (2002), 32 % of the sediment that is generated in the catchment, is deposited in Lake Victoria (i.e. 2 209 Mg year-1 or 0.7 Mg ha-1 year-1). The main buffer in the study area is papyrus at the shore of Lake Victoria. Also sugarcane can be a major buffer. However, the sugarcane-area is intersected by com-pounds, landing sites, footpaths and main roads that generate large amounts of

  8. Identification of immunoreactive FSH and LH cells in the cichlid fish Cichlasoma dimerus during the ontogeny and sexual differentiation.

    Science.gov (United States)

    Pandolfi, Matías; Lo Nostro, Fabiana L; Shimizu, Akio; Pozzi, Andrea G; Meijide, Fernando J; Vazquez, Graciela Rey; Maggese, M Cristina

    2006-10-01

    Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) expressing cells were detected in pituitary, brain and ovary of the Perciform cichlid fish Cichlasoma dimerus. This detection was carried out by immunohistochemistry (IHC) and Western blot techniques using antisera of the Cyprinodontiform Fundulus heteroclitus raised against the conservative region of the teleost betaFSH and the betaLH subunits. The estimated molecular weights were 24 kDa for LH and 19 and 15 kDa for FSH. In the adult pituitary, both cell types were distributed along mid and ventral zones of the proximal pars distalis (PPD, mid-immunoreactive cells), and along the ventral and dorsal external border of the pars intermedia (PI, high-immunoreactive cells). Double IHC showed that FSH and LH are mainly expressed in different pituitary cells. FSH cells were detected in the pituitary around day 21 after hatching (ah) (prior to sex differentiation), while LH cells were detected by day 60 ah (during the sexual differentiation period). A correlation between gonadal sex differentiation and FSH was demonstrated in a 15 days organ culture system. FSH and LH neurons were localized in the nucleus lateralis tuberis and their fibers project through the ventral hypothalamus, preoptic area and neurohypophysis. FSH neurons differentiated on day 21 ah, while LH neurons appeared on day 15 ah. In the ovary, the immunoreactivity for both FSH and LH was restricted to the cytoplasm of previtellogenic and early vitellogenic oocytes.

  9. Social status-dependent nest choice of territorial males under reproductive parasitism in a Lake Tanganyika cichlid Telmatochromis vittatus.

    Science.gov (United States)

    Ota, K; Kohda, M

    2011-03-01

    Field and laboratory studies were conducted to examine how territorial males of a Lake Tanganyika cichlid Telmatochromis vittatus balance the conflicting demands on nest choice between occupying large nests with more females and avoiding reproductive parasitism (nest piracy, which is adopted by the largest males in the population). Pirates less frequently intruded the nests farther from neighbours, perhaps due to the costs associated with travelling between nests. The field experiment showed that territorial male T. vittatus sacrificed the fitness benefits that large nests offer and instead prioritized occupying the nests farther from neighbours on which fewer pirates intruded. The field observations suggested that they adopt different strategies for nest choice according to their relative competitive ability to pirates; the large territorial males, who are size-matched to pirates and can defend their nests against them, compete for larger nests among the more-isolated nests, whereas subordinate territorial males, which are smaller than pirates and thus inferior to them, compete for the more-isolated nests among the less-isolated nests. These findings suggest that the territorial male T. vittatus chooses the more-isolated nests to avoid pirate males at the expense of occupying large nests. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  10. Yolk-sac larval development of the substrate-brooding cichlid Archocentrus nigrofasciatus in relation to temperature.

    Science.gov (United States)

    Vlahos, Nikolaos; Vasilopoulos, Michael; Mente, Eleni; Hotos, George; Katselis, George; Vidalis, Kosmas

    2015-09-01

    In order to conserve and culture the cichlid fish Archocentrus nigrofasciatus, more information about its reproductive biology and its larval behavior and morphogenesis is necessary. Currently, temperatures ranging from 21 to 27 °C are used in ornamental aquaculture hatcheries. Lower temperatures are preferred to reduce the costs of water heating, and 23 °C is usually the selected temperature. However, there is limited information on culturing protocols for ornamental species and most of the information generated on this topic remains scarce. Thus, the present study examines the morphological development of Archocentrus nigrofasciatus during the yolk-sac period up to the age of 100 h post-hatching in relation to 2 temperature regimes used in ornamental aquaculture: a temperature of 27 °C (thermal optimum) and a decreased temperature of 23 °C (thermal tolerance). The results of this study suggest that the 27 °C temperature generates intense morphological changes in yolk-sac development in a shorter period. This has advantages as it reduces the time of yolk-sac larval development, and, thus, minimizes the transition phase to exogenous feeding and maximizes the efficiency at which yolk is converted into body tissues. The present paper provides necessary information to produce freshwater ornamental fish with better practices so as to increase larval survival and capitalize on time for growth. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  11. Acquisition of Lateralized Predation Behavior Associated with Development of Mouth Asymmetry in a Lake Tanganyika Scale-Eating Cichlid Fish.

    Directory of Open Access Journals (Sweden)

    Yuichi Takeuchi

    Full Text Available The scale-eating cichlid Perissodus microlepis with asymmetric mouth is an attractive model of behavioral laterality: each adult tears off scales from prey fishes' left or right flanks according to the direction in which its mouth is skewed. To investigate the development of behavioral laterality and mouth asymmetry, we analyzed stomach contents and lower jaw-bone asymmetry of various-sized P. microlepis (22 ≤ SL<115 mm sampled in Lake Tanganyika. The shapes of the pored scales found in each specimen's stomach indicated its attack side preference. Early-juvenile specimens (SL<45 mm feeding mainly on zooplankton exhibited slight but significant mouth asymmetry. As the fish acquired scale-eating (45 mm ≤ SL, attack side preference was gradually strengthened, as was mouth asymmetry. Among size-matched individuals, those with more skewed mouths ate more scales. These findings show that behavioral laterality in scale-eating P. microlepis is established in association with development of mouth asymmetry which precedes the behavioral acquisition, and that this synergistic interaction between physical and behavioral literalities may contribute to efficient scale-eating.

  12. High levels of interspecific gene flow in an endemic cichlid fish adaptive radiation from an extreme lake environment.

    Science.gov (United States)

    Ford, Antonia G P; Dasmahapatra, Kanchon K; Rüber, Lukas; Gharbi, Karim; Cezard, Timothee; Day, Julia J

    2015-07-01

    Studying recent adaptive radiations in isolated insular systems avoids complicating causal events and thus may offer clearer insight into mechanisms generating biological diversity. Here, we investigate evolutionary relationships and genomic differentiation within the recent radiation of Alcolapia cichlid fish that exhibit extensive phenotypic diversification, and which are confined to the extreme soda lakes Magadi and Natron in East Africa. We generated an extensive RAD data set of 96 individuals from multiple sampling sites and found evidence for genetic admixture between species within Lake Natron, with the highest levels of admixture between sympatric populations of the most recently diverged species. Despite considerable environmental separation, populations within Lake Natron do not exhibit isolation by distance, indicating panmixia within the lake, although individuals within lineages clustered by population in phylogenomic analysis. Our results indicate exceptionally low genetic differentiation across the radiation despite considerable phenotypic trophic variation, supporting previous findings from smaller data sets; however, with the increased power of densely sampled SNPs, we identify genomic peaks of differentiation (FST outliers) between Alcolapia species. While evidence of ongoing gene flow and interspecies hybridization in certain populations suggests that Alcolapia species are incompletely reproductively isolated, the identification of outlier SNPs under diversifying selection indicates the radiation is undergoing adaptive divergence. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  13. Tolerance of nonindigenous cichlid fishes (Cichlasoma urophthalmus, Hemichromis letourneuxi) to low temperature: laboratory and field experiments in south Florida

    Science.gov (United States)

    Schofield, Pamela J.; Loftus, William F.; Kobza, Robert M.; Cook, Mark I.; Slone, Daniel H.

    2010-01-01

    The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.

  14. High frequency of multiple paternity in broods of a socially monogamous cichlid fish with biparental nest defence.

    Science.gov (United States)

    Sefc, Kristina M; Mattersdorfer, Karin; Sturmbauer, Christian; Koblmüller, Stephan

    2008-05-01

    In several animal taxa, genetic analyses have demonstrated that social monogamy and biparental brood care do not preclude polygamous reproduction. Few studies have been conducted in fish, but in fish species without alternative reproductive phenotypes, social monogamy was largely congruent with genetic parentage. In contrast to these findings, we report an exceptionally high level of multiple paternity in a socially monogamous cichlid fish with biparental nest defence (Variabilichromis moorii), inferred from microsatellite and mitochondrial data of 10 broods. Whereas all offspring in a nest shared a common mother, each brood was sired by 2 to > 10 males. None of the inferred sires was assigned a large proportion of the brood. Paternity was estimated as the minimum number of sires required to explain multilocus offspring genotypes, and as the maximum-likelihood number of sires given population allele frequencies. Analysis of simulated brood genotypes suggested that, although these two methods tend to under- and overestimate, respectively, the true number of sires, primary sires with many offspring in a brood would have been detected. Hence, the genetic data indicate that the nest tending males suffer substantial cuckoldry and provide alloparental care for a large number of unrelated fry. We have no data on the social status of the cuckolding males, but due to synchronous spawning of pairs and commitment to brood care of paired males, it is possible that most of the parasitic spawners are solitary males.

  15. Preliminary assessment of the cocial, economic and environmental impacts of Water Hyacinth in Lake Victoria basin and status of control

    OpenAIRE

    Mailu, A.M.

    2001-01-01

    The paper presents preliminary data collected in an assessment of the social, economic and environmental impacts of water hyacinth in the Lake Victoria Basin. A summary of the status of control and strategies for the future is given. The report draws on field observations made, studies through interviews of affected communities and organisations, personal communications and published reports by scientists in the region. Lake Victoria, the world’s second largest freshwater body, su...

  16. Species of Gyrodactylus von Nordmann, 1832 (Platyhelminthes: Monogenea) from cichlids from Zambezi and Limpopo river basins in Zimbabwe and South Africa: evidence for unexplored species richness.

    Science.gov (United States)

    Zahradníčková, Petra; Barson, Maxwell; Luus-Powell, Wilmien J; Přikrylová, Iva

    2016-09-01

    New findings on Gyrodactylus spp. parasitising African cichlids in southern Africa are presented, comprising data from Zimbabwe and South Africa. Morphometry of opisthaptoral hard parts in combination with nuclear ribosomal DNA sequences confirmed the presence of six species of Gyrodactylus von Nordmann, 1832. Three new species are described from fishes in Zimbabwe: Gyrodactylus chitandiri n. sp. from the gill arches of Coptodon rendalli (Boulenger) and Pseudocrenilabrus philander (Weber); Gyrodactylus occupatus n. sp. from the fins of Oreochromis niloticus (L.), Pharyngochromis acuticeps (Steindachner) and P. philander; and Gyrodactylus parisellei n. sp. from the fins of O. niloticus, P. philander and Tilapia sp. Gyrodactylus nyanzae Paperna, 1973 was also identified from the gills of O. niloticus and C. rendalli collected from two localities in Zimbabwe; these findings represent new host and locality records for this parasite. Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011 was identified from P. philander collected in South Africa and Zimbabwe thereby providing new host and locality records for this parasite. Finally, Gyrodactylus yacatli García-Vásquez, Hansen, Christison, Bron & Shinn, 2011 was collected from the fins of O. niloticus and P. philander studied in Zimbabwe; this represents the first record of this species from the continent of Africa. Notably, this study improves upon the knowledge of Gyrodactylus spp. parasitising cichlids from these southern African regions. All species studied were recorded from at least two different cichlid host species indicating trend for a wide range of Gyrodactylus hosts in Africa. Accordingly, this supports the idea of intensive host switching in the course of their evolution.

  17. Towards understanding hydroclimatic change in Victoria, Australia – preliminary insights into the "Big Dry"

    Directory of Open Access Journals (Sweden)

    A. S. Kiem

    2010-03-01

    Full Text Available Since the mid-1990s the majority of Victoria, Australia, has experienced severe drought conditions (i.e. the "Big Dry" characterized by streamflow that is the lowest in approximately 80 years of record. While decreases in annual and seasonal rainfall totals have also been observed, this alone does not seem to explain the observed reduction in flow. In this study, we investigate the large-scale climate drivers for Victoria and demonstrate how these modulate the regional scale synoptic patterns, which in turn alter the way seasonal rainfall totals are compiled and the amount of runoff per unit rainfall that is produced. The hydrological implications are significant and illustrate the need for robust hydrological modelling, that takes into account insights into physical mechanisms that drive regional hydroclimatology, in order to properly understand and quantify the impacts of climate change (natural and/or anthropogenic on water resources.

  18. Use of regionalisation approach to develop fire frequency curves for Victoria, Australia

    Science.gov (United States)

    Khastagir, Anirban; Jayasuriya, Niranjali; Bhuyian, Muhammed A.

    2017-11-01

    It is important to perform fire frequency analysis to obtain fire frequency curves (FFC) based on fire intensity at different parts of Victoria. In this paper fire frequency curves (FFCs) were derived based on forest fire danger index (FFDI). FFDI is a measure related to fire initiation, spreading speed and containment difficulty. The mean temperature (T), relative humidity (RH) and areal extent of open water (LC2) during summer months (Dec-Feb) were identified as the most important parameters for assessing the risk of occurrence of bushfire. Based on these parameters, Andrews' curve equation was applied to 40 selected meteorological stations to identify homogenous stations to form unique clusters. A methodology using peak FFDI from cluster averaged FFDIs was developed by applying Log Pearson Type III (LPIII) distribution to generate FFCs. A total of nine homogeneous clusters across Victoria were identified, and subsequently their FFC's were developed in order to estimate the regionalised fire occurrence characteristics.

  19. Art at Second Hand: Prints after European Pictures in Victoria before 1870

    Directory of Open Access Journals (Sweden)

    Alison Inglis

    2011-06-01

    Full Text Available This article examines the significance of the large number of European reproductive prints present in the public and private art collections of early colonial Victoria. Several factors are identified as contributing to this popularity; ranging from the suitability of the print medium for the export market to the existence of informed print connoisseurs amongst colonial collectors and artists. This article also demonstrates some of the typical features of Australian art history; in that it is concerned with the evaluation of the Australian art world through reference to European culture (the centre-periphery debate and also that it limits its discussion to the art of a particular Australian state (Victoria. The nineteenth-century division of Australia into different colonies had ramifications for Australian art history that continue to the present day – namely; the tendency to interpret colonial artistic activities from a regional perspective.

  20. ZnO-Fe2O3 heterojunction for photocatalytic degradation of victoria blue dye

    Science.gov (United States)

    Kumar, Pushpendra; Khatri, Taslimahemad; Bawa, Harpreet; Kaur, Jashandeep

    2017-07-01

    In the present study, ZnO-Fe2O3 heterojunction has been successfully synthesized by co-precipitation method for photocatalytic degradation of Victoria blue dye. The synthesized samples were subjected to XRD for microstructural characterization and scanning electron microscopy for morphological investigation. The typical X-ray diffraction pattern shows exhaustive evolution of hexagonal wurtzite phase of ZnO and α-Fe2O3 having crystalline in the range of 34-54 nm. The synthesized samples were applied for degradation of victoria blue dye under UV illumination. ZnO-Fe2O3 heterojunction showed higher photocatalytic activity for dye degradation compared to bare ZnO. This rise in photocatalytic activity can be attributed to enhanced charge separation derived from coupling of ZnO and Fe2O3. In this manuscript, the effect of photocatalyst dose, irradiation time and initial dye concentration on photodegradation of dye is reported in detail.

  1. Strain and displacement measurements for the June 9, 1980 Victoria, Mexico Earthquake

    Science.gov (United States)

    Darby, D.; Nyland, E.; Suarez, F.; Chavez, D.; Gonzalez, J.

    A microgeodetic network 22 km south east of Est. Guadalupe Victoria, Baja California Norte, installed in late May 1980, has been resurveyed in an experiment that started 12 hours after the June 9, 1980 Victoria earthquake, which had an epicenter at 10 km depth about 12 km from the network. The resurvey was complete by June 13. Both the initial observations and the resurvey were done with HP3800 distance meter equipment. Some angular control was provided with a Wild T3 theodolite. The network underwent a compressive strain of 7 ± 3 micro strain essentially parallel the Cerro Prieto fault about the time of the earthquake. Strains of this size are associated with simple dislocation models of earthquakes of this magnitude. Its direction appears to be anomalous however. This may indicate compression related to soil liquefaction processes or strain near the end of the slip plane.

  2. The effect of high rearing densities on the growth of juveniles of the cichlid, cichlasoma managuense (Günther, 1869 (ESP

    Directory of Open Access Journals (Sweden)

    Jorge Günther Nonell

    2016-03-01

    Full Text Available The effect of high density culture on the growth of juvenile jaguar cichlids was investigated. Mean growth rate decrease with density, while the growth rate of the largest fishes was not affected. Reduction in mean growth resulted from a greater number of stunted individuals as well as from a higher degree of stunting. Skewness appears to be a better indicator of competitive effects than the coefficient of variation. It is concluded that at least in stagnant waters, even high densities do not affect the strong dominance hierarchy which establishes among guapote juveniles.

  3. Impacts of changing water price and availability on irrigated dairy farms in northern Victoria

    OpenAIRE

    Ho, Christie K.M.; Armstrong, Dan P.; Doyle, Peter T.; Malcolm, Bill

    2004-01-01

    Farming systems throughout the Murray-Darling Basin are under increasing scrutiny from the perspective of ecological sustainability of farm and catchment systems. In northern Victoria, the dairy industry is a major user of water, and contributes to the environmental issues. Changes in irrigation water price, availability and policy will invariably impact on the viability of dairy farming in this region, but the diversity of dairy farm systems suggests that the impact will vary between farms. ...

  4. Imperialist women in Edwardian Britain : the Victoria League, 1899-1914

    OpenAIRE

    Riedi, Elizabeth L.

    1998-01-01

    This thesis, based on private papers, society records, autobiographies and memoirs, newspapers and periodicals, examines one mainly female imperialist organisation - the Victoria League - and the women who ran it. It considers two related questions - what made Edwardian women imperialist, and how, within the limits of Edwardian society, could they express their imperialism? The thesis shows that several of the League's founders and executive had visited South Africa during or s...

  5. Lake Victoria wetlands and the ecology of the Nile tilapia, Oreochromis niloticus Linne

    OpenAIRE

    Balirwa, J.S.

    1998-01-01

    An ecological study of wetlands was undertaken in northern Lake Victoria (East Africa) between 1993 and 1996 with a major aim of characterising shallow vegetation-dominated interface habitats, and evaluating their importance for fish, in particular, for the stocked and socio-economically important Oreochromis niloticus LINNÉ (the Nile tilapia). From field and laboratory experiments, five major habitat types could be defined by the type of the dominant emergent ma...

  6. Intestinal schistosomiasis among preschool children along the shores of Lake Victoria in Uganda

    DEFF Research Database (Denmark)

    Nalugwa, A.; Olsen, Annette; Tukahebwa, M. E.

    2015-01-01

    prevalence and intensity of infection were examined in 3058 children from 5 districts along Lake Victoria shoreline, eastern Uganda. For each child one stool sample was collected on three consecutive days. The Kato-Katz technique was used to prepare stool smears on slides for microscopic examination. Short...... for schistosomiasis takes preschool children into consideration and that health education on transmission of schistosomiasis is delivered to the endemic communities regularly....

  7. A Bottom-Up Understanding of Illegal, Unreported, and Unregulated Fishing in Lake Victoria

    Directory of Open Access Journals (Sweden)

    Joseph Luomba

    2016-10-01

    Full Text Available Illegal, unreported, and unregulated (IUU fishing is a major concern in fisheries management around the world. Several measures have been taken to address the problem. In Lake Victoria, the alleviation of IUU fishing is implemented through the Regional Plan of Action (RPOA-IUU, which restricts use of certain fishing gear, as well as prohibits fishing in closed areas and during closed seasons. Despite the long-term efforts to monitor and control what goes on in the fisheries, IUU fishing has persisted in Lake Victoria. Inspired by interactive governance theory, this paper argues that the persistence of IUU fishing could be due to different images that stakeholders have about the situation, rather than the lack of management competency. Through structured interviews with 150 fisheries stakeholders on Ijinga Island in the southeastern part of Lake Victoria, Tanzania, using paired comparison questionnaires, the study elicits stakeholders’ perspective about the severity of different locally-pertinent fishing-related activities. The results show that while fisheries stakeholder groups agree on their judgments about certain fishing gears, some differences are also apparent. For instance, fisheries managers and scientists do not always agree with fishing people about what activities cause the most damage to fisheries resources and ecosystem. Further, they tend to consider some IUU fishing-related activities less damaging than some non-IUU fishing. Such disparity creates governability challenges, pointing to the need to revisit relevant regulatory measures and to make them consistent with the knowledge and judgments of all stakeholders. Based on these findings, we discuss governing interventions that may contribute to addressing IUU fishing in Lake Victoria and elsewhere.

  8. A Comparison of digestive Tract Morphology in muskoxen and caribou from Victoria Island, Northwest Territories, Canada

    Directory of Open Access Journals (Sweden)

    Hans Staaland

    1997-04-01

    Full Text Available Although caribou and muskoxen coexist in close proximity on southeastern Victoria Island, they appear primarily adapted to different diets and foraging strategies. Visual inspection and analysis of rumen contents for fiber and lignin from the study (unpubl. also indicate a predominantly graminoid diet in the muskoxen and a more varied diet with a substantial browse component in the caribou.This should reduce the likelihood of competition for limited food resources in winter.

  9. Salinity in Water Markets : An ExperimentalInvestigation of the Sunraysia Salinity Levy, Victoria

    OpenAIRE

    C. Duke; L. Gangadharan

    2005-01-01

    Irrigation can have a significant negative impact on the environment. Irrigation impacts contribute a significant portion to the estimated forty six million dollar cost per annum of salinity in the Murray River, Australia. Policies available to regulators include externality taxes and levies. In 2002 the Victorian Government introduced a system of salinity levies in the irrigation regions of Sunraysia, northern Victoria. These levies differ from typical taxes because they also introduce trade...

  10. Satellite-Based Assessment of the spatial extent of Aquatic Vegetation in Lake Victoria

    Science.gov (United States)

    Clark, W.; Aligeti, N.; Jeyaprakash, T.; Martins, M.; Stodghill, J.; Winstanley, H.

    2011-12-01

    Lake Victoria in Africa is the second largest freshwater lake in the world and is known for its abundance of aquatic wildlife. In particular over 200 different fish species are caught and sold by local fisherman. The lake is a major contributor to the local economy as a corridor of transportation, source of drinking water, and source of hydropower. However, the invasion of aquatic vegetation such as water hyacinth in the lake has disrupted each of these markets. Aquatic vegetation now covers a substantial area of the coastline blocking waterways, disrupting hydropower, hindering the collection of drinking water and decreasing the profitability of fishing. The vegetation serves as a habitat for disease carrying mosquitoes as well as snakes and snails that spread the parasitic disease bilharzia. The current control measures of invasive aquatic vegetation rely on biological, chemical and mechanical control. The objective of this study was to utilize remote sensing to map aquatic vegetation within Lake Victoria from 2000 to 2011. MODIS, Landsat 4-5TM, and Landsat 7-ETM imagery was employed to perform change detections in vegetation and identify the extent of aquatic vegetation throughout the years. The efficiency of containment efforts were evaluated and ideal time for application of such efforts were suggested. A methodology for aquatic vegetation surveillance was created. The results of this project were presented as a workshop to the Lake Victoria Fisheries Organization, SERVIR, and other partner organizations. The workshop provided instruction into the use of NASA and other satellite derived products. Time series animations of the spatial extent of aquatic vegetation within the lake were created. By identifying seasons of decreased aquatic vegetation, ideal times to employ control efforts were identified. SERVIR will subsequently utilize the methodologies and mapping results of this study to develop operational aquatic vegetation surveillance for Lake Victoria.

  11. Leuconidae (Crustacea: Cumacea) from the collections of the Museum Victoria, Australia.

    Science.gov (United States)

    Gerken, Sarah

    2016-01-21

    The collections of the Museum Victoria have yielded six new leuconid species in five genera from Australian waters: Austroleucon adiazetos n. sp., A. dolosolevis n. sp., Eudorellopsis mykteros n. sp., Kontiloleucon australiensis n. gen., n. sp., Leucon (Alytoleucon) dolichorhinos n. sp., Ommatoleucon megalopos n. sp. as well as the new genus Kontiloleucon. Leucon (Leucon) echinolophotos n. sp. is a new species from off Enderby Land, Antarctica. Keys to the Australian leuconid genera and species are included.

  12. Recent reduction in the water level of Lake Victoria has created more habitats for Anopheles funestus

    Directory of Open Access Journals (Sweden)

    Futami Kyoko

    2008-07-01

    Full Text Available Abstract Background The water level of Lake Victoria has fallen more than 1.5 m since 1998, revealing a narrow strip of land along the shore. This study determined whether the recent drop in the water level has created additional breeding grounds for malaria vectors. Methods The recent and past shorelines were estimated using landmarks and a satellite image. The locations of breeding habitats were recorded using a GPS unit during the high and low lake water periods. GIS was used to determine whether the breeding habitats were located on newly emerged land between the new and old shorelines. Results Over half of the breeding habitats existed on newly emerged land. Fewer habitats for the Anopheles gambiae complex were found during the low water level period compared to the high water period. However, more habitats for Anopheles funestus were found during the high water level period, and they were all located on the newly emerged land. Conclusion The recent reduction in water level of Lake Victoria has increased the amount of available habitat for A. funestus. The results suggest that the water drop has substantially affected the population of this malaria vector in the Lake Victoria basin, particularly because the lake has a long shoreline that may harbour many new breeding habitats.

  13. Urban eutrophication and its spurring conditions in the Murchison Bay of Lake Victoria.

    Science.gov (United States)

    Kabenge, Martin; Wang, Hongtao; Li, Fengting

    2016-01-01

    The efficiency of Lake Victoria in providing its ecosystem services to riparian states, both immediate and along the Nile river basin, is strongly related to its water quality. Over the past few decades, eutrophication has increased in the lake arising from increased inflow of nutrients. This study was carried out in the Murchison Bay area of Lake Victoria with the aims of assessing the progress of eutrophication nutrient enrichment into the lake between 1990 and 2014. Using Landsat satellite floating algae index (FAI) products and data from laboratory analysis of water samples, the study revealed that floating algae reoccurred periodically with coverage varying between 1 and 18 km(2). The findings also indicated that the range of nitrate-nitrogen concentrations increased greatly with maximum concentrations recorded at 31.2 mg l(-1) in 2007 from 0.084 mg l(-1) in 1990. The soluble reactive phosphorus concentration range showed a maximum of 1.45 mg l(-1) in 2007 from 0.043 mg l(-1) in 1990. The chlorophyll levels increased from an average of 17 μg l(-1) in 1992 by threefold in 1996 but had however declined and halved in intensity by 2011. The eutrophication that has occurred in Lake Victoria over the past decades has been due to pollution from industrial, residential, and agricultural areas within the catchment.

  14. Women's experience of domiciliary postnatal care in Victoria and South Australia: a population-based survey.

    Science.gov (United States)

    Biro, Mary Anne; Yelland, Jane S; Sutherland, Georgina A; Brown, Stephanie J

    2012-11-01

    Despite the expansion of postnatal domiciliary services, we know little about the women receiving visits and how they regard their care. The aim of this study is to examine the provision of postnatal domiciliary care from a consumer perspective. All women who gave birth in September-October 2007 in South Australia and Victoria were mailed questionnaires 6 months after the birth. Women were asked if they had received a midwifery home visit, and to rate the care they received. More women in South Australia reported receiving a domiciliary visit than in Victoria (88.0% v. 76.0%) and they were more likely to rate their care as 'very good' (69.1% v. 63.4%). Younger women, women on a lower income, who were holding a healthcare concession card or who had not completed secondary education were less likely to receive a visit. Although the majority of women in public maternity care in Victoria and South Australia receive domiciliary care and rate it positively, there are significant state-based differences. Those more likely to benefit from domiciliary care are less likely to receive a visit. There is a need to further explore the purpose, aims and content of domiciliary care at individual and state-wide levels.

  15. Sediment Production from Settlements and Farmlands within Lake Victoria Shoreline Zone in Uganda and Tanzania

    Directory of Open Access Journals (Sweden)

    Isabirye, M.

    2010-01-01

    Full Text Available In spite of the general acceptance that the current land use changes are unlikely to yield a sustainable environment, the source of sediment that causes eutrophication in Lake Victoria is not clearly understood. It is hypothesized that roads, footpaths, and compounds (settlement are a major source of sediments. This study was conducted on the northern Lake Victoria shoreline to determine the rate of sediment generated by agricultural and settlement land use types. Results show that settlements generate significantly higher sediment yields i.e. between 17- 87 ton.ha-1. yr -1 whereas agricultural land use types produced between 0-27 ton ha-1.yr-1. The high sediment yield from settlements is attributed to high runoff coefficients and the occurrence of gully erosion. The high sediment yield from settlements justifies the need to conduct further investigations on the contribution of settlements to sediment production in catchments with different soil - landscape and climatic setting in the Lake Victoria catchment.

  16. Comparison of mortality following hospitalisation for isolated head injury in England and Wales, and Victoria, Australia.

    Directory of Open Access Journals (Sweden)

    Belinda J Gabbe

    Full Text Available BACKGROUND: Traumatic brain injury (TBI remains a leading cause of death and disability. The National Institute for Health and Clinical Excellence (NICE guidelines recommend transfer of severe TBI cases to neurosurgical centres, irrespective of the need for neurosurgery. This observational study investigated the risk-adjusted mortality of isolated TBI admissions in England/Wales, and Victoria, Australia, and the impact of neurosurgical centre management on outcomes. METHODS: Isolated TBI admissions (>15 years, July 2005-June 2006 were extracted from the hospital discharge datasets for both jurisdictions. Severe isolated TBI (AIS severity >3 admissions were provided by the Trauma Audit and Research Network (TARN and Victorian State Trauma Registry (VSTR for England/Wales, and Victoria, respectively. Multivariable logistic regression was used to compare risk-adjusted mortality between jurisdictions. FINDINGS: Mortality was 12% (749/6256 in England/Wales and 9% (91/1048 in Victoria for isolated TBI admissions. Adjusted odds of death in England/Wales were higher compared to Victoria overall (OR 2.0, 95% CI: 1.6, 2.5, and for cases <65 years (OR 2.36, 95% CI: 1.51, 3.69. For severe TBI, mortality was 23% (133/575 for TARN and 20% (68/346 for VSTR, with 72% of TARN and 86% of VSTR cases managed at a neurosurgical centre. The adjusted mortality odds for severe TBI cases in TARN were higher compared to the VSTR (OR 1.45, 95% CI: 0.96, 2.19, but particularly for cases <65 years (OR 2.04, 95% CI: 1.07, 3.90. Neurosurgical centre management modified the effect overall (OR 1.12, 95% CI: 0.73, 1.74 and for cases <65 years (OR 1.53, 95% CI: 0.77, 3.03. CONCLUSION: The risk-adjusted odds of mortality for all isolated TBI admissions, and severe TBI cases, were higher in England/Wales when compared to Victoria. The lower percentage of cases managed at neurosurgical centres in England and Wales was an explanatory factor, supporting the changes made to the NICE

  17. Aquatic and fisheries survey of the upper Victoria Nile: a report prepared for AES Nile Power Bujagali hydropower project, final report

    OpenAIRE

    2000-01-01

    The aquatic ecosystem of the Upper Victoria Nile is part of a wider complex of water bodies (lakes and rivers) in Uganda that is of immense socioeconomic importance, especially the fisheries. A source of food, income, energy, irrigation and drinking water, the protection, sustainable use and management of the Upper Victoria Nile water resources are vital to Uganda's economy. The Upper Victoria Nile,due to its abundance of socio-economic benefits,provides a significant contribution to Ugand...

  18. Reproductive and metabolic state differences in olfactory responses to amino acids in a mouth brooding African cichlid fish.

    Science.gov (United States)

    Nikonov, Alexandre A; Butler, Julie M; Field, Karen E; Caprio, John; Maruska, Karen P

    2017-08-15

    Olfaction mediates many crucial life-history behaviors such as prey detection, predator avoidance, migration and reproduction. Olfactory function can also be modulated by an animal's internal physiological and metabolic states. While this is relatively well studied in mammals, little is known about how internal state impacts olfaction in fishes, the largest and most diverse group of vertebrates. Here we apply electro-olfactograms (EOGs) in the African cichlid fish Astatotilapia burtoni to test the hypothesis that olfactory responses to food-related cues (i.e. l-amino acids; alanine and arginine) vary with metabolic, social and reproductive state. Dominant males (reproductively active, reduced feeding) had greater EOG magnitudes in response to amino acids at the same tested concentration than subordinate males (reproductively suppressed, greater feeding and growth rates). Mouth brooding females, which are in a period of starvation while they brood fry in their mouths, had greater EOG magnitudes in response to amino acids at the same tested concentration than both recovering and gravid females that are feeding. Discriminant function analysis on EOG magnitudes also grouped the male (subordinate) and female (recovering, gravid) phenotypes with higher food intake together and distinguished them from brooding females and dominant males. The slope of the initial negative phase of the EOG also showed intra-sexual differences in both sexes. Our results demonstrate that the relationship between olfaction and metabolic state observed in other taxa is conserved to fishes. For the first time, we provide evidence for intra-sexual plasticity in the olfactory response to amino acids that is influenced by fish reproductive, social and metabolic state. © 2017. Published by The Company of Biologists Ltd.

  19. Simultaneous delimitation of species and quantification of interspecific hybridization in Amazonian peacock cichlids (genus cichla) using multi-locus data.

    Science.gov (United States)

    Willis, Stuart C; Macrander, Jason; Farias, Izeni P; Ortí, Guillermo

    2012-06-22

    Introgression likely plays a significant role in evolution, but understanding the extent and consequences of this process requires a clear identification of species boundaries in each focal group. The delimitation of species, however, is a contentious endeavor. This is true not only because of the inadequacy of current tools to identify species lineages, but also because of the inherent ambiguity between natural populations and species paradigms. The result has been a debate about the supremacy of various species concepts and criteria. Here, we utilized multiple separate sources of molecular data, mtDNA, nuclear sequences, and microsatellites, to delimit species under a polytypic species concept (PTSC) and estimate the frequency and genomic extent of introgression in a Neotropical genus of cichlid fishes (Cichla). We compared our inferences of species boundaries and introgression under this paradigm to those when species are identified under a diagnostic species concept (DSC). We find that, based on extensive molecular data and an inclusive species concept, 8 separate biological entities should be recognized rather than the 15 described species of Cichla. Under the PTSC, fewer individuals are expected to exhibit hybrid ancestry than under the DSC (~2% vs. ~12%), but a similar number of the species exhibit introgression from at least one other species (75% vs. 60%). Under either species concept, the phylogenetic breadth of introgression in this group is notable, with both sister species and species from different major mtDNA clades exhibiting introgression. Introgression was observed to be a widespread phenomenon for delimited species in this group. While several instances of introgressive hybridization were observed in anthropogenically altered habitats, most were found in undisturbed natural habitats, suggesting that introgression is a natural but ephemeral part of the evolution of many tropical species. Nevertheless, even transient introgression may facilitate an

  20. Experimentally increased temperature and hypoxia affect stability of social hierarchy and metabolism of the Amazonian cichlid Apistogramma agassizii.

    Science.gov (United States)

    Kochhann, Daiani; Campos, Derek Felipe; Val, Adalberto Luis

    2015-12-01

    The primary goal of this study was to understand how changes in temperature and oxygen could influence social behaviour and aerobic metabolism of the Amazonian dwarf cichlid Apistogramma agassizii. Social hierarchies were established over a period of 96h by observing the social interactions, feeding behaviour and shelter use in groups of four males. In the experimental environment, temperature was increased to 29°C in the high-temperature treatment, and oxygen lowered to 1.0mg·L(-1)O2 in the hypoxia treatment. Fish were maintained at this condition for 96h. The control was maintained at 26°C and 6.6mg·L(-1)O2. After the experimental exposure, metabolism was measured as routine metabolic rate (RMR) and electron transport system (ETS) activity. There was a reduction in hierarchy stability at high-temperature. Aggression changed after environmental changes. Dominant and subdominant fish at high temperatures increased their biting, compared with control-dominant. In contrast, hypoxia-dominant fish decreased their aggressive acts compared with all other fish. Shelter use decreased in control and hypoxic dominant fish. Dominant fish from undisturbed environments eat more than their subordinates. There was a decrease of RMR in fish exposed to the hypoxic environment when compared with control or high-temperature fish, independent of social position. Control-dominant fish had higher RMR than their subordinates. ETS activity increased in fish exposed to high temperatures; however, there was no effect on social rank. Our study reinforces the importance of environmental changes for the maintenance of hierarchies and their characteristics and highlights that most of the changes occur in the dominant position. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Pleistocene to holocene expansion of the black-belt cichlid in Central America, Vieja maculicauda (Teleostei: Cichlidae.

    Directory of Open Access Journals (Sweden)

    Caleb D McMahan

    Full Text Available The distributions of many Northern Hemisphere organisms have been influenced by fluctuations in sea level and climatic conditions during Pleistocene interglacial periods. These cycles are associated with range contraction and refugia for northern-distributed organisms as a response to glaciers. However, lower sea levels in the tropics and sub-tropics created available habitat for expansion of the ranges of freshwater organisms. The goal of this study was to use ecological niche modeling to test the hypothesis of north to south range expansion of Vieja maculicauda associated with Pleistocene glacial cycles. Understanding the biogeography of this widespread species may help us better understand the geology and interconnectivity of Central American freshwaters. Occurrence data for V. maculicauda was based on georeferencing of all museum records of specimens recovered from FishNet2. General patterns of phylogeographic structure were assessed with mtDNA. Present day niche models were generated and subsequently projected onto paleoclimatic maps of the region during the Last Interglacial, Last Glacial Maximum, and mid-Holocene. Phylogenetic analysis of mtDNA sequence data showed no phylogeographic structure throughout the range of this widespread species. Present day niche models were congruent with the observed distribution of V. maculicauda in Central America. Results showed a lack of suitable freshwater habitat in northern Central America and Mexico during the Last Interglacial, with greatest range expansion during the Last Glacial Maximum and mid-Holocene. Results support the hypothesis of a north to south range expansion of V. maculicauda associated with glacial cycles. The wide distribution of this species compared to other closely related cichlids indicates the latter did not respond to the degree of V. maculicauda in expansion of their distributions. Future work aimed at comparisons with other species and modeling of future climatic scenarios

  2. Cichlid fishes in the Angolan headwaters region: molecular evidence of the ichthyofaunal contact between the Cuanza and Okavango-Zambezi systems.

    Science.gov (United States)

    Musilová, Zuzana; Kalous, Lukáš; Petrtýl, Miloslav; Chaloupková, Petra

    2013-01-01

    The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii and Serranochromis macrocephalus, using both mitochondrial and nuclear markers. We found evidence for ichthyofaunal contact and gene flow between the Cuanza and Okavango-Zambezi watersheds in the Bié Plateau in central Angola. Waterfalls and rapids also appeared to restrict genetic exchange among populations within the Cuanza basin. Further, we found that the Angolan Serranochromis cichlid fishes represent a monophyletic lineage with respect to other haplochromines, including the serranochromines from the Congo and Zambezi rivers. This study represents an important initial step in a biodiversity survey of this extremely poorly explored region, as well as giving further understanding to species distributions and gene flow both between and within river basins.

  3. Cichlid fishes in the Angolan headwaters region: molecular evidence of the ichthyofaunal contact between the Cuanza and Okavango-Zambezi systems.

    Directory of Open Access Journals (Sweden)

    Zuzana Musilová

    Full Text Available The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii and Serranochromis macrocephalus, using both mitochondrial and nuclear markers. We found evidence for ichthyofaunal contact and gene flow between the Cuanza and Okavango-Zambezi watersheds in the Bié Plateau in central Angola. Waterfalls and rapids also appeared to restrict genetic exchange among populations within the Cuanza basin. Further, we found that the Angolan Serranochromis cichlid fishes represent a monophyletic lineage with respect to other haplochromines, including the serranochromines from the Congo and Zambezi rivers. This study represents an important initial step in a biodiversity survey of this extremely poorly explored region, as well as giving further understanding to species distributions and gene flow both between and within river basins.

  4. A new cryptogonimid (Digenea) from the Mayan cichlid, Cichlasoma urophthalmus (Osteichthyes: Cichlidae), in several localities of the Yucatán Peninsula, Mexico.

    Science.gov (United States)

    Razo-Mendivil, Ulises; Rosas-Valdez, Rogelio; Pérez-Ponce de León, Gerardo

    2008-12-01

    Oligogonotylus mayae n.sp. is described from the intestine of the Mayan cichlid Cichlasoma urophthalmus (Günther) in Ría Lagartos, Ría Celestún, and Estero Progreso, Yucatán State. This is the second species described for Oligogonotylus Watson, 1976, the other being O.manteri Watson, 1976. The new species is readily distinguished from O. manteri by the anterior extension of the vitelline follicles. In O. Manteri, Vitelline follicles are found entirely in the hindbody, extending posteriorly to mid-testicular level. Vitelline follicles in the new species extend from teh anterior margin of posterior testis to the region between the bentral sucker and the pharynx. comparison of approximately 1,850 bases of ribosomal DNA (ITS1, ITS2, 5.8S, and 28S), and 400 bases of cytochrome c oxidase subunit I (cox1) strongly supports the status of O. mayae as a new species, as compared to O. manteri collected from cichlids in other localities of Mexico, Belize, and Guatemala.

  5. British History is Their History: Britain and the British Empire in the History Curriculum of Ontario, Canada and Victoria, Australia 1930-1975

    National Research Council Canada - National Science Library

    Stephen J Jackson

    2017-01-01

    This article investigates the evolving conceptions of national identity in Canada and Australia through an analysis of officially sanctioned history textbooks in Ontario, Canada and Victoria, Australia...

  6. Monitoring geodynamic activity in the Victoria Land, East Antarctica: Evidence from GNSS measurements

    Science.gov (United States)

    Zanutta, A.; Negusini, M.; Vittuari, L.; Cianfarra, P.; Salvini, F.; Mancini, F.; Sterzai, P.; Dubbini, M.; Galeandro, A.; Capra, A.

    2017-10-01

    GNSS networks in Antarctica are a fundamental tool to define actual crustal displacements due to geological and geophysical processes and to constrain the glacial isostatic models (GIA). A large network devoted to the detection and monitoring of crustal deformations in the Northern Victoria Land (Victoria Land Network for DEFormation control - VLNDEF), was monumented during the 1999-2000 and 2000-2001 field campaigns, as part of Italian National Program for Antarctic Research and surveyed periodically during the Southern summer seasons. In this paper, GPS observations of VLNDEF collected over a more than 15-year span, together with various selected POLENET sites and more than 70 IGS stations, were processed with Bernese Software, using a classical double difference approach. A solution was obtained combining NEQs by means of ADDNEQ2/FODITS tools embedded in Bernese Software. All the Antarctic sites were kept free and a subset of 50 IGS stations were used to frame VLNDEF into ITRF2008. New evidence provided by analysis of GPS time series for the VLNDEF network is presented; also displacements along the vertical component are compared with the recently published GIA models. The absolute velocities indicate an overall displacement of the northern Victoria Land region along the south-east direction (Ve = 10.6 mm/yr, Vn = -11.5 mm/yr) and an average uplift rate of Vu = 0.5 mm/yr. Two GIA models have been analyzed: ICE-6G_C-VM5a proposed by Argus et al. (2014), Peltier et al. (2015) and W12A_v1 by Whitehouse et al. (2012a,b). Up rates, predicted over the VLNDEF sites by the mentioned GIA models, have been extracted and compared with those observed. A preliminary comparison with GPS-derived vertical rates shows that the Victoria Land ICE-6G_C-VM5 and W12A_v1 GIA models predict overestimated uplift rates of 0.7 and 0.9 mm/yr weighted mean residuals respectively. The mean horizontal relative motions within the Victoria Land (VL) area are in most cases negligible, while only

  7. Conditions for initiating Lake Victoria haplochromine (Oreochromis esculentus) primary cell cultures from caudal fin biopsies.

    Science.gov (United States)

    Filice, Melissa; Lee, C; Mastromonaco, Gabriela F

    2014-10-01

    The global decline of freshwater fishes has created a need to cryopreserve biological materials from endangered species in an effort to conserve the biodiversity within this taxon. Since maternal gametes and embryos from fish are difficult to cryopreserve, somatic cells obtained from caudal fins have become an increasingly popular resource as they contain both maternal and paternal DNA ensuring valuable traits are not lost from the population. Somatic cells stored in cryobanks can be used to supplement endangered populations with genetically valuable offspring with the use of assisted reproductive technologies. However, initiating primary cell cultures from caudal fin biopsies of endangered species can be challenging as standardized protocols have not yet been developed. The objective of this study was to identify culture conditions, including antibiotic supplementation, biopsy size, and culture temperature, suitable for establishing primary cell cultures of ngege (Oreochromis esculentus), a critically endangered African cichlid. Six-millimeter caudal fin biopsies provided sufficient material to develop a primary cell culture when incubated at 25°C using standard fish cell culture medium containing 1× Primocin. Further investigation and application of these culture conditions for other endangered freshwater fishes is necessary.

  8. Stable isotope paleoecology of Late Pleistocene Middle Stone Age humans from the Lake Victoria basin, Kenya.

    Science.gov (United States)

    Garrett, Nicole D; Fox, David L; McNulty, Kieran P; Faith, J Tyler; Peppe, Daniel J; Van Plantinga, Alex; Tryon, Christian A

    2015-05-01

    Paleoanthropologists have long argued that environmental pressures played a key role in human evolution. However, our understanding of how these pressures mediated the behavioral and biological diversity of early modern humans and their migration patterns within and out of Africa is limited by a lack of archaeological evidence associated with detailed paleoenvironmental data. Here, we present the first stable isotopic data from paleosols and fauna associated with Middle Stone Age (MSA) sites in East Africa. Late Pleistocene (∼100-45 ka, thousands of years ago) sediments on Rusinga and Mfangano Islands in eastern Lake Victoria (Kenya) preserve a taxonomically diverse, non-analog faunal community associated with MSA artifacts. We analyzed the stable carbon and oxygen isotope composition of paleosol carbonate and organic matter and fossil mammalian tooth enamel, including the first analyses for several extinct bovids such as Rusingoryx atopocranion, Damaliscus hypsodon, and an unnamed impala species. Both paleosol carbonate and organic matter data suggest that local habitats associated with human activities were primarily riverine woodland ecosystems. However, mammalian tooth enamel data indicate that most large-bodied mammals consumed a predominantly C4 diet, suggesting an extensive C4 grassland surrounding these riverine woodlands in the region at the time. These data are consistent with other lines of paleoenvironmental evidence that imply a substantially reduced Lake Victoria at this time, and demonstrate that C4 grasslands were significantly expanded into equatorial Africa compared with their present distribution, which could have facilitated dispersal of human populations and other biotic communities. Our results indicate that early populations of Homo sapiens from the Lake Victoria region exploited locally wooded and well-watered habitats within a larger grassland ecosystem. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. The molecular epidemiology of norovirus outbreaks in Victoria, 2014 to 2015
.

    Science.gov (United States)

    Bruggink, Leesa D; Moselen, Jean M; Marshall, John A

    2017-03-31

    Noroviruses are a leading cause of outbreaks of gastroenteritis. This study examined the incidence and molecular characteristics of norovirus outbreaks in healthcare and non-healthcare settings in Victoria, Australia, over 2 years (2014-2015). Norovirus was detected in 65.7% and 60.4% of gastroenteritis outbreaks investigated for the years 2014 and 2015 respectively. There was a significant decline in the number of norovirus outbreaks in the period 2014 to 2015 although in both years norovirus outbreaks peaked in the latter part of the year. Norovirus Open Reading Frame (ORF) 2 (capsid) genotypes identified included GI.2, GI.3, GI.4, GI.5, GI.6, GI.9, GII.2, GII.3, GII.4, GII.6, GII.7, GII.8, GII.13 and GII.17. GII.4 was the most common genotype detected. In addition, the following ORF 1/ORF 2 recombinant forms were confirmed: GII.P4_NewOrleans_2009/GII.4_Sydney_2012, GII.P12/GII.3, GII.Pb (GII.21)/GII.3, GII.Pe/GII.2 and GII.Pe/GII.4_Sydney_2012. A significant decline was noted in the chief norovirus strain GII.Pe/GII.4_Sydney_2012 between 2014 and 2015 but there was a re-emergence of a GII.P4_ NewOrleans _2009 norovirus strain. Outbreaks involving the GII.P17/GII.17 genotype were also detected for the first time in Victoria. GI genotypes circulating in Victoria for the 2 years 2014 and 2015 underwent a dramatic change between the 2 years of the survey. Many genotypes could occur in both healthcare and non-healthcare settings although GI.3, GII.6, and GII.4 were significantly more common in healthcare settings. The study emphasises the complex way in which norovirus circulates throughout the community.

  10. Sex and sport: sexual risk behaviour in young people in rural and regional Victoria.

    Science.gov (United States)

    Kong, Fabian Y S; Hocking, Jane S; Link, Chris Kyle; Chen, Marcus Y; Hellard, Margaret E

    2010-06-01

    To determine the prevalence of chlamydia and understand sexual risk behaviour in 16-29 year olds in rural Victoria through a chlamydia testing program undertaken at local sporting clubs. Young people were recruited from the Loddon Mallee region of Victoria, Australia between May and September 2007. After a night of sporting practice, participants provided a first pass urine sample and completed a brief questionnaire about sexual risk behaviour. Those positive for chlamydia were managed by telephone consultation with a practitioner from Melbourne Sexual Health Centre. A total of 709 young people participated (77% male, 23% female) in the study; 77% were sexually active. Overall chlamydia prevalence in sexually active participants was 5.1% (95% confidence interval [CI]: 3.4-7.3); 7.4% in females (95% CI: 3.5-13.6) and 4.5% in males (95% CI: 2.7-6.9). Approximately 60% of males and 20% of females consumed alcohol at high 'Risky Single Occasion Drinking' levels at least weekly and 60% had used an illicit drug in their lifetime. Nearly 45% reported having sex in the past year when they usually would not have because they were too drunk or high. Sexually transmissible infection (STI) knowledge was generally poor and only 25% used a condom the last time they had sex. Chlamydia prevalence was high in our study population. Many participants had poor knowledge about STIs and low condom use. These findings combined with high levels of risky alcohol use and having sex while intoxicated highlights the need for programs in rural and regional Victoria that combine both STI testing and prevention and education programs.

  11. The Most Effective Methods for Delivering Severe Weather Early Warnings to Fishermen on Lake Victoria.

    Science.gov (United States)

    Tushemereirwe, Richard; Tuhebwe, Doreen; Cooper, Mary Ann; D'ujanga, Florence Mutonyi

    2017-02-22

    Introduction : It is estimated that five thousand people die on Lake Victoria every year by drowning which is triggered by severe weather hazards like lightning. Objectives :  In order to improve predictability of severe weather conditions on Lake Victoria, there is need to deliver timely and effective Severe Weather Early Warning Systems (SWEWS) to those at risk. On Lake Victoria, previous SWEW service trials ceased with the end of the funding grants. This study therefore assessed the possibility of sustaining the SWEW service by assessing willingness to pay.   Methods : An assessment was conducted between March and May 2015 to determine the SWEW service improvements desired by the population. A convenience sample of respondents was gathered and interviewed during impromptu visits to landing sites on Lake Victoria. The respondents were also among community members that had earlier participated in a pilot assessing the feasibility of mobile phones is delivering SWEW alerts.  Semi-structured questionnaires were administered to fishermen and fisher folks at the landing site to gather suggestions/strategies for (i) better design and implementation of SWEW service, (ii) use of smart phones, and (iii) their ability and willingness to pay for a SWEW service. Results were presented as frequencies. Results : Two hundred fifteen respondents from fourteen landing sites (communities) were interviewed. Over 50% of the respondents (113/215) were aware about at least one community member who had been injured due to lightening on the lake in the past year. Ninety two percent (198/215) of the respondents reported using mobile phones as their main tool of communication but only 4% had smart phones that could receive early warning weather alerts through internet connectivity. Seventy five percent of respondents said they would welcome a system that could deliver commercial weather alerts and 65% were willing to pay for such a service.   Conclusions : A SWEW service is feasible

  12. Gambling revenues as a public administration issue: electronic gaming machines in Victoria.

    Science.gov (United States)

    Pickernell, David; Keast, Robyn; Brown, Kerry; Yousefpour, Nina; Miller, Chris

    2013-12-01

    Gambling activities and the revenues derived have been seen as a way to increase economic development in deprived areas. There are also, however, concerns about the effects of gambling in general and electronic gaming machines (EGMs) in particular, on the resources available to the localities in which they are situated. This paper focuses on the factors that determine the extent and spending of community benefit-related EGM-generated resources within Victoria, Australia, focusing in particular on the relationships between EGM activity and socio-economic and social capital indicators, and how this relates to the community benefit resources generated by gaming.

  13. A Baseline Air Quality Assessment Onboard a Victoria Class Submarine: HMCS Windsor

    Science.gov (United States)

    2006-05-01

    défense Canada – Toronto; May 2006. Pour faciliter l’élaboration de futurs plans de gestion de la qualité de l’air à bord des nouveaux sous-marins de...visant à améliorer la gestion de la qualité de l’air à bord de sous-marins de classe Victoria. Ces recommandations comprennent : l’examen de tous les... ambient air from the WSC (centre of the torpedo racks, used as bunk space); Senior Rates Mess Accommodation Space (aft compartment); Junior Rates

  14. Gastropod diversity, distribution and abundance in habitats with and without anthropogenic disturbances in Lake Victoria, Kenya

    DEFF Research Database (Denmark)

    Lange, C. N.; Kristensen, Thomas K.; Madsen, Henry

    2013-01-01

    We investigated freshwater gastropod diversity, abundance and distribution in habitats with and without anthropogenic disturbance in two localities, Ndere in the Winam Gulf and Mbita Point, Lake Victoria, Kenya, from May 2002 to January 2004. A total of 133 984 gastropod specimens belonging to 15...... and other wastes so as to reduce local eutrophication, thereby reducing risks associated with transmission of potential snail-borne diseases. © 2013...... species were recorded, 14 from Mbita and 12 from Ndere. Two species, Ferrissia kavirondica and Cleopatra cridlandi, which were recorded only from undisturbed habitats, could be indicators of least disturbed habitats. Water chemistry did differ between fish landing sites and undisturbed habitats at some...

  15. Microbial quality and safety of fresh and dried Rastrineobola argentea from Lake Victoria, Tanzania

    DEFF Research Database (Denmark)

    Baniga, Zebedayo; Dalsgaard, Anders; Mhongole, Ofred J

    2017-01-01

    Rastrineobola argentea (silver cyprinid/sardines) is an important commercial fish species found in Lake Victoria. It is an important protein source for consumers in several African countries including Tanzania. A cross-sectional study was conducted using standard methods to assess the bacteriolog...... sites contained 30% (n = 20) and those from the markets contained 15% (n = 20) Salmonella spp. Salmonella spp. were not detected in sardines dried on racks. To conclude, sun drying of sardines on racks is an effective drying method providing a safe product for human consumption....

  16. A new species of Anabarhynchus (Diptera: Therevidae from an ocean beach in south east Victoria

    Directory of Open Access Journals (Sweden)

    David Ferguson

    2014-09-01

    Full Text Available Anabarhynchus Macquart 1848 is a large genus of the Therevidae (Diptera that are endemic to Australasia with a couple of described species from Melanesia. We describe and illustrate Anabarhynchus oceanus sp. n., a species found on ocean beaches in eastern Victoria, Australia. The species shares most characters with the monobasic A. kampmeierae species group of Lyneborg (2001, but also shares a unique feature of the male genitalia with the endemic New Zealand genus Megathereva Lyneborg, 1992. This new species brings the total number of described Australian species in the genus to 113.

  17. VICTORIA: A mechanistic model of radionuclide behavior in the reactor coolant system under severe accident conditions. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Heams, T J [Science Applications International Corp., Albuquerque, NM (United States); Williams, D A; Johns, N A; Mason, A [UKAEA, Winfrith, (England); Bixler, N E; Grimley, A J [Sandia National Labs., Albuquerque, NM (United States); Wheatley, C J [UKAEA, Culcheth (England); Dickson, L W [Atomic Energy of Canada Ltd., Chalk River, ON (Canada); Osborn-Lee, I [Oak Ridge National Lab., TN (United States); Domagala, P; Zawadzki, S; Rest, J [Argonne National Lab., IL (United States); Alexander, C A [Battelle, Columbus, OH (United States); Lee, R Y [Nuclear Regulatory Commission, Washington, DC (United States)

    1992-12-01

    The VICTORIA model of radionuclide behavior in the reactor coolant system (RCS) of a light water reactor during a severe accident is described. It has been developed by the USNRC to define the radionuclide phenomena and processes that must be considered in systems-level models used for integrated analyses of severe accident source terms. The VICTORIA code, based upon this model, predicts fission product release from the fuel, chemical reactions involving fission products, vapor and aerosol behavior, and fission product decay heating. Also included is a detailed description of how the model is implemented in VICTORIA, the numerical algorithms used, and the correlations and thermochemical data necessary for determining a solution. A description of the code structure, input and output, and a sample problem are provided.

  18. La construcción de legitimidad del Frente para la Victoria (1988-1991 Frente para la Victoria's construction of legitimacy (1988-1991

    Directory of Open Access Journals (Sweden)

    Pamela Sosa

    2011-06-01

    Full Text Available El trabajo aborda la construcción de legitimidad del Frente para la Victoria (FV en el escenario político de Santa Cruz desde su nacimiento en 1988 hasta llegar a la gobernación en 1991. Se identifican tres fuentes de legitimidad construidas de manera alternativa al debilitamiento de la credibilidad de los partidos políticos tradicionales: la UCR, el PJ, el PI y el MID, entre otros. En este contexto, el Frente para la Victoria desplegó sus estrategias de legitimación apelando a la unidad de lo diverso y sumando referentes individuales de todo el arco político. Por otro lado, apeló a través de sus discursos y la conformación de los elencos y organizaciones a representar la fragmentación social propia de una sociedad compuesta por capas migratorias y, por último, construyó una novedosa oferta política a-partidaria acorde a las representaciones de la crisis estatal a mediados del '80 a partir de la reivindicación de los valores de la gestión, la eficiencia, el orden, el trabajo y la gobernabilidad. Sus estrategias de legitimación muestran cómo la primera etapa de construcción de poder político del FV fue efecto de su trayectoria en la frontera de los débiles grupos sociales y políticos.O trabalho aborda a construção de legitimidade do Frente para la Victoria (FV no cenário político de Santa Cruz desde seu nascimento em 1988 até chegar ao governo em 1991. Identificam-se três fontes de legitimidade construídas de maneira alternativa ao enfraquecimento da credibilidade dos partidos políticos tradicionais: a UCR, o PJ, o PI e o MID, entre outros. Neste contexto, o Frente para la Victoria desdobrou suas estratégias de legitimação apelando à unidade do que for diverso e somando referências individuais de todo o arco político. Por outro lado, apelou, através de seus discursos e a conformação dos elencos e organizações, a representar a fragmentação social própria de uma sociedade composta por camadas migrat

  19. Brain levels of arginine-vasotocin and isotocin in dominant and subordinate males of a cichlid fish.

    Science.gov (United States)

    Almeida, Olinda; Gozdowska, Magdalena; Kulczykowska, Ewa; Oliveira, Rui F

    2012-02-01

    The nonapeptides arginine-vasotocin (AVT) and isotocin (IT), which are the teleost homologues of arginine-vasopressin and oxytocin in mammals, have well established peripheral effects on osmoregulation and stress response, and central effects on social behavior. However, all studies that have looked so far into the relationship between these nonapeptides and social behavior have used indirect measures of AVT/IT activity (i.e. immunohistochemistry of AVT/IT immunoreactive neurons, or AVT/IT or their receptors mRNA expression with in situ hybridization or qPCR) and therefore direct measures of peptide levels in relation to social behavior are still lacking. Here we use a recently developed high-performance liquid chromatography analysis with fluorescence detection (HPLC-FL) method to quantify the levels of both AVT and IT in macro-dissected brain areas [i.e. olfactory bulbs, telencephalon, diencephalon, optic tectum, cerebellum, and hindbrain (= rhombencephalon minus cerebellum)] and pituitary of dominant and subordinate male cichlid fish (Oreochromis mossambicus). The pituitary shows higher levels of both peptides than any of the brain macroareas, and the olfactory bulbs have the highest AVT among all brain areas. Except for IT in the telencephalon there is a lack of correlations between central levels and pituitary peptide levels, suggesting an independent control of hypophysial and CNS nonapeptide secretion. There were also no correlations between AVT and IT levels either for each brain region or for the pituitary gland, suggesting a decoupled activity of the AVT and IT systems at the CNS level. Subordinate AVT pituitary levels are significantly higher than those of dominants, and dominant hindbrain IT levels are significantly higher than those of subordinates, suggesting a potential involvement of AVT in social stress in subordinate fish and of IT in the regulation of dominant behavior at the level of the hindbrain. Since in this species dominant males use urine

  20. A New Genus and Two New Species of Proteocephalidean Tapeworms (Cestoda) from Cichlid Fish (Perciformes: Cichlidae) in the Neotropics.

    Science.gov (United States)

    de Chambrier, Alain; Pinacho-Pinacho, Carlos Daniel; Hernández-Orts, Jesus Servando; Scholz, Tomáš

    2017-02-01

    Cichlidocestus n. gen. is proposed to accommodate 2 new species of proteocephalidean cestodes, Cichlidocestus gillesi n. sp. from Cichlasoma amazonarum in Peru (type species) and Cichlidocestus janikae n. sp. from Hypsophrys nicaraguensis (all Perciformes: Cichlidae) in Costa Rica. The new genus is unique among all but 1 proteocephalidean genera in the position of the ovary that occupies the middle and posterior thirds of the median region of proglottids (vs. the ovary in the posterior third of proglottids near their posterior margin in all but 1 remaining taxa). In addition, Cichlidocestus is typified by the presence of a voluminous, spherical, internal seminal vesicle, several pairs of ventral excretory canals in the medulla, a pyramidal, quadrilobed scolex with an apical muscular sucker, and the posterior extent of the testes that may reach almost to the posterior margin of proglottids. The new genus shares the position of the ovary and its extension with Sciadocephalus (also a parasite of cichlids in the Neotropics as the new taxon); in all remaining proteocephalideans the ovary occupies the posterior third only. Sciadocephalus differs from Cichlidocestus by a different morphology of the scolex, which possesses an umbrella-like metascolex that is markedly wider than the strobila, the number of ventral osmoregulatory canals, and development of the uterus, which forms capsule-like formations filled with eggs in Sciadocephalus megalodiscus (vs. simple lateral diverticula in Cichlidocestus spp.). Both new species of Cichlidocestus can be easily distinguished from one another by the anterior extent of the poral vitelline follicles (anterior to the cirrus-sac, i.e., preporal, in C. gillesi vs. posterior, i.e., only postporal in C. janikae), size of the eggs (diameter of the external layer of the embryophore of C. gillesi 30-33 μm vs. 44-46 μm in C. janikae), and the number of uterine lateral diverticula (16-21 on 1 side in C. gillesi vs. only 8-12 in C. janikae

  1. Influence of the Pearl River estuary and vertical mixing in Victoria Harbor on water quality in relation to eutrophication impacts in Hong Kong waters.

    Science.gov (United States)

    Yin, Kedong; Harrison, Paul J

    2007-06-01

    This study presents water quality parameters such as nutrients, phytoplankton biomass and dissolved oxygen based on 11 years of water quality data in Victoria Harbor and examined how the Pearl River estuary discharge in summer and year round sewage discharge influenced these parameters. Nutrients in Victoria Harbor were strongly influenced by both the Pearl River and sewage effluent, as indicated by the high NO(3) inputs from the Pearl River in summer and higher NH(4) and PO(4) in Victoria Harbor than both its sides. N:P ratios were low in the dry season, but increased to >16:1 in the wet season, suggesting that P is potentially the most limiting nutrient in this area during the critical period in the summer. Although there were generally high nutrients, the phytoplankton biomass was not as high as one would expect in Victoria Harbor. In fact, there were high concentrations of chl near the bottom well below the photic zone. Salinity near the bottom was lower in Victoria Harbor than at the two entrances to Victoria Harbor, suggesting strong vertical mixing within Victoria Harbor. Therefore, strong vertical mixing and horizontal advection appear to play an important role in significantly reducing eutrophication impacts in Victoria Harbor. Consequently, dissolved oxygen near the bottom was low in summer, but only occasionally dipped to 2 mgL(-1) despite the high organic loading from sewage effluent.

  2. Round the bend: a brief history of mental health nursing in Victoria, Australia 1848 to 1950's.

    Science.gov (United States)

    Sands, Natisha Marina

    2009-06-01

    This paper presents a history of mental health nursing in Victoria, Australia from 1848 to the 1950's, or the asylum years to the era of the mental hospital. The research for this historical overview was conducted as part of a literature review for a mental health nursing doctoral thesis, which included an account of the evolution of the profession from asylum attendant to the present time. The literature reviewed for this project revealed a distinct lack of a coherent, chronological account of the historical development of mental health nursing in Victoria, and this paper seeks to address that knowledge gap.

  3. Aprendiendo a entender. Victoria Ocampo y su descubrimiento de los Estados Unidos

    Directory of Open Access Journals (Sweden)

    Plotkin, Mariano

    2002-12-01

    Full Text Available The article analyzes the evolving relationship that Argentine intellectual and cultural entrepreneur Victoria Ocampo established with the United States. Through her trajectory the article analyzes broader topics such as the evolution of the Argentine social and intellectual élite’s project of modernization. Ocampo was at the same time a typical and a unique representative of the Argentine social élite. She was typical in the way she was educated in a cosmopolitan environment. She was unique because she occupied a central figure in the Argentine field of cultural production since the 1920 until her death in the late 1970s.

    El artículo analiza la evolución de la compleja relación que la intelectual y empresaria cultural argentina Victoria Ocampo estableció con los Estados Unidos. A través de esta trayectoria, el artículo analiza también temas mas amplios como la evolución de los proyectos modernizadores de la élite social e intelectual argentina. Ocampo era a la vez una representante típica y única de su clase social. Era típica por la manera en que fue educada en un ambiente cosmopolita. Era única por el lugar central que ocupó en el campo intelectual argentino desde la década de 1920 hasta su muerte a finales de los años 70.

  4. Reasons women give for contemplating or undergoing abortion: a qualitative investigation in Victoria, Australia.

    Science.gov (United States)

    Kirkman, Maggie; Rosenthal, Doreen; Mallett, Shelley; Rowe, Heather; Hardiman, Annarella

    2010-11-01

    To increase understanding of women's perspectives on considering or undergoing elective abortion. Qualitative study. A large public women's hospital in the state of Victoria, Australia. Sixty women who had contacted a public pregnancy advisory service in Victoria, Australia, seeking information, advice, or appointments in relation to an unplanned or unwanted pregnancy. Qualitative telephone interviews. The iterative qualitative analysis employed the five stages of a thematic framework approach. Themes in women's accounts of considering or undergoing elective abortion. Women's accounts emphasized their reasons for considering or seeking abortion. Decisions were made in the context of their lives as a whole; influences were usually contingent and multiple. Reasons related to the woman herself, the potential child, existing children, her partner and other significant relationships, and financial matters. This research used qualitative methods to produce the only recent study of its kind in Australia. Women's accounts reveal the complex personal and social contexts within which reproductive events must be comprehended and the thoughtfulness with which they make decisions. Results of this research will assist health-care professionals to increase their insights into women's reproductive experiences. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Individual and community correlates of young people's high-risk drinking in Victoria, Australia.

    Science.gov (United States)

    Livingston, Michael; Laslett, Anne-Marie; Dietze, Paul

    2008-12-01

    To examine key individual- and community-level correlates of regular very high-risk drinking (more than 20 drinks at least 12 times a year for males and more than 11 drinks at least 12 times a year for females) among young (16-24) drinkers in Victoria. CATI survey of 10,879 young Victorian drinkers. Multi-level modelling of correlates of proportion drinking at very high-risk levels at both individual (e.g. age, gender) and community levels (e.g. alcohol outlet density, remoteness). One-fifth of the sample reported regular (at least monthly) very high-risk drinking. Significant individual-level correlates of very high-risk drinking included age, gender, cultural background, recreational spending money, life stage, living situation, family conflict and age at first drink. Significant community-level correlates included remoteness (living in a rural area) and packaged liquor outlet density. The study highlights a range of important factors relating to regular drinking of dangerous amounts of alcohol by youth. Interventions aimed at preventing early initiation or managing recreational spending should be explored. Further, regulatory management of packaged liquor outlets and or remote rural communities in Victoria with high levels of dangerous drinking should be a priority.

  6. A longitudinal study of the cost of food in Victoria influenced by geography and nutritional quality.

    Science.gov (United States)

    Palermo, Claire; McCartan, Julia; Kleve, Sue; Sinha, Kompal; Shiell, Alan

    2016-06-01

    To monitor the cost and affordability of a nutritious diet and to assess the influence of distance from the capital city and socioeconomic status on the cost of nutritious food in Victoria. Twenty-six of Victoria's 79 local government areas (33%) were randomly chosen for inclusion in the study. A random sample of stores was selected for inclusion from each local government area. The cost of the 44 'healthy' and 10 'discretionary' food and drinks in the healthy food basket for a family of four for a fortnight was collected during the winter and summer of 2012, 2013 and 2014. The mean cost of the basket increased from $424.06 ± 38.22 in winter 2012 to $451.19 ± 33.83 in summer 2014 (pcost. These findings show that a healthy diet may be unaffordable for some Victorians. The cost of food is a key factor influencing intake. Public health strategies may need to consider strategies to make healthy food more affordable for some. © 2015 Public Health Association of Australia.

  7. Prescription opioid dispensing and prescription opioid poisoning: Population data from Victoria, Australia 2006 to 2013.

    Science.gov (United States)

    Berecki-Gisolf, Janneke; Hassani-Mahmooei, Behrooz; Clapperton, Angela; McClure, Roderick

    2017-02-01

    To describe recent trends in opioid prescribing and prescription opioid poisoning resulting in hospitalisation or death in Victoria, Australia. This is a population-based ecological study of residents of Victoria, 2006 - 14. Australian Bureau of Statistics residential population data were combined with Pharmaceutical Benefits Scheme (PBS) opioid prescription data, Victorian Admitted Episodes Data (VAED) and cause of death data. Annual opioid dispensings increased by 78% in 2006 - 13, from 0.33 to 0.58 per population. Opioid use increased with age: in 2013, 14% of Victorian residents aged ≥65 years filled at least one oxycodone prescription. In 2006 - 14, prescription opioid related hospital admissions increased by 6.8% per year, from 107 to 187 /1,000,000 person-years; 56% were due to intentional self-poisoning. Annual deaths increased from 21 to 28 /1,000,000 persons, in 2007 - 11. Admissions and deaths peaked at 25-44 years. Although both opioid prescribing and poisoning have increased, there is discrepancy between the exposed group (dispensings increased with age) and those with adverse consequences (rates peaked at ages 25-44 years). A better understanding is needed of drivers of prescribing and adverse consequences. Together with monitoring of prescribing and poisoning, this will facilitate early detection and prevention of a public health problem. © 2016 The Authors.

  8. VIRGINIA WOOLF EN LOS TESTIMONIOS DE VICTORIA OCAMPO: TENSIONES ENTRE FEMINISMO Y COLONIALISMO

    Directory of Open Access Journals (Sweden)

    Alicia Salomone

    2006-11-01

    Full Text Available En este artículo se analizan una serie de textos ensayísticos de la escritora argentina Victoria Ocampo (1890-1979, en los que ella aborda la relación que la ligó a Virginia Woolf, su principal referente en términos literarios y feministas. Desde perspectivas teóricas postcoloniales y feministas, se hace una interpretación de los textos de Ocampo, observando los límites que la cosmovisión colonialista impone no solo a sus diálogos con Woolf, sino al despliegue de su propia escrituraThis article reviews a series of essays by the Argentine writer Victoria Ocampo (1890-1979 in which she deals with the relationship that bound her to Virginia Woolf, her main referent in literary and feminist terms. From postcolonial theoretical perspectives, an interpretation of Ocampo's texts is made, while noticing the limits that the colonialist cosmic vision imposed not only on her dialogues with Woolf but on the development of her own writing

  9. Reproductive efficiency of Thoroughbred and Standardbred horses in north-east Victoria.

    Science.gov (United States)

    Nath, L C; Anderson, G A; McKinnon, A O

    2010-05-01

    To evaluate the reproductive efficiency of horse farms in north-east Victoria and identify aspects of management to be targeted for improving reproductive efficiency. Retrospective study. Records from seven Thoroughbred (TB) and four Standardbred (STB) studs in north-east Victoria from 1990 to 2001 were reviewed; 8813 cycles in 4455 mares were analysed. TB mares were inseminated by natural mating, whereas STB mares (89%) were artificially inseminated. The overall early pregnancy rate per cycle was 68.8% for TB mares and for STB mares, 68.3%. Multiple pregnancy per cycle was more frequent in TB (8.3%) than in STB (4.6%) mares (P reproductive status within the TB than the STB mares. Pregnancy rate per cycle among stallions ranged from 48% to 79%. On-farm pregnancy rates in both breeds were higher than previously reported and likely reflect improvements in reproductive management. The disparity between breeds in the inseminations per cycle and proportion of barren mares exposed the differing structures of the two industries, and presents a target for improving the reproductive efficiency in STBs. The difference between breeds in the multiple pregnancy rate per cycle likely reflects the higher ovulation rate of TB mares. The variability in pregnancy rate per cycle between the 22 stallions was associated with differences in individual inherent fertility and the quality of stallion management.

  10. Acute stress ulceration prophylaxis: point prevalence surveys in intensive care units in Victoria, 1997 and 2005.

    Science.gov (United States)

    Robertson, Megan S; Wilson, Stuart J; Cade, John F

    2008-03-01

    To assess current practice in acute stress ulceration (ASU) prophylaxis in adult intensive care units in Victoria, Australia, in 1997 and 2005. Point prevalence surveys using a structured telephone questionnaire of ASU prophylaxis practices were performed in adult ICUs in Victoria on 11 November 1997 and 13 April 2005. All Victorian ICUs identified on each study day participated, comprising 30 ICUs in 1997 and 35 ICUs in 2005. Presence of a clinical protocol or guideline for ASU prophylaxis increased significantly from 23% in 1997 to 54% in 2005 (P = 0.01). Overall provision of ASU prophylaxis to ICU patients also increased significantly from 67% in 1997 to 86% in 2005 (P 1997 to 45% in 2005 (P 1997 and 2005. Use of ASU prophylaxis for patients admitted to Victorian ICUs increased significantly from 1997 to 2005, with an associated increase in the presence of protocols or guidelines for ASU prophylaxis. Although agents currently used for ASU prophylaxis in Victorian ICUs are consistent with available evidence, we are concerned that ASU prophylaxis is given to all patients admitted to the ICU rather than targeted to patients in high-risk categories.

  11. Re-visitando a Federica Montseny. Una lectura de La Victoria y sus lecturas

    Directory of Open Access Journals (Sweden)

    Lozano de la Pola, Ana

    2006-06-01

    Full Text Available This article wants to be a close reading of La Victoria, Federica Montseny’s novel published in 1925, in order to achieve two objectives: on the one hand, to break down the clichés that normally appear in Montseny’s work –her “revolutionary melodrama”- as a perfect example of the eternal “ethic-aesthetic” paradox and, on the other hand, to point out the capability of this kind of study to dynamize the so-called “women’s literature” in the context of the XX Century Spanish literature.Este artículo pretende hacer una lectura atenta de La Victoria, novela de Federica Montseny publicada en 1925, con dos objetivos: en primer lugar, deshacer los clichés que suelen tratar la obra de esta autora como representante de la eterna “paradoja ético-estética” que suponen sus “folletines revolucionarios” y, en segundo, señalar la capacidad que tiene el estudio de este tipo de obras para dinamizar la categoría de “literatura de mujeres” con el fin de evitar su estancamiento en el ámbito de la literatura española del s. XX.

  12. Comparison of Sterol Biomarkers for Sewage with other Measures in Victoria Harbour, B.C., Canada

    Science.gov (United States)

    Mudge, S. M.; Lintern, D. Gwyn

    1999-01-01

    A lipid biomarker survey was conducted in Victoria Harbour, Canada, to compare the distribution of sewage-derived organic matter with existing results from bacterial studies. Previous surveys [Miller (1993) Report prepared by Capital Regional District Engineering Department, Victoria, B.C. Canada and Miller et al. (1995) Report prepared by CRD Environmental Services Group and Aquatic Science Consultants Ltd., B.C., Canada] of sewage contamination in the harbour were based principally on infrequent faecal coliform counts. The use of lipid biomarkers to determine time-averaged concentrations of sewage components in sediments may be a more appropriate method for defining areas where sewage is causing environmental or human health risks. 5β-Coprostanol was measured together with other sterols, fatty acids and fatty alcohols. Generally, sewage contamination shown by these lipid biomarkers was coincident with high faecal coliform counts from previous studies. However, this survey suggests, contrary to faecal coliform counts, that Portage Inlet was a region where sewage had accumulated in the sediments, possibly due to nearby overflow facilities or tidal pumping. Although the bacterial counts were low, sewage-derived organic matter was accumulating in the slack areas. In sediments of the Gorge and West Bay there were low faecal biomarker concentrations; this was probably due to the strong tidal currents which do not allow faecal matter to settle in sediments. Faecal coliform counts, however, indicated poor water quality in these same regions but this probably reflects fresh discharges passing through this area without leading to settlement.

  13. Rural Health and Spiritual Care Development: A Review of Programs across Rural Victoria, Australia.

    Science.gov (United States)

    Carey, Lindsay B; Hennequin, Christine; Krikheli, Lillian; O'Brien, Annette; Sanchez, Erin; Marsden, Candace R

    2016-06-01

    Given declining populations in rural areas and diminishing traditional religious support, this research explores whether spiritual care education programs would be beneficial for and appreciated by those working in rural health and/or community organizations. An overview of literature identified three dominant rural health issues affecting the provision of spiritual care in rural areas, namely the disparity between rural and urban areas in terms of resources, the lack of access to services, plus the need for education and training within rural areas. Spiritual Health Victoria Incorporated (Victoria, Australia) sought to address these issues with the implementation of a variety of spiritual education programs within rural areas. Results of an evaluation of these programs are presented specifying participant demographics, reasons why participants attended, their evaluation of the program and any recommendations for future programs. In overall terms, the results indicated that at least 90% of participants favorably rated their attended program as either 'very good' or 'good' and indicated that the main reason for their attendance was to develop their own education and/or practice of spiritual care within their rural context for the benefit of local constituents. Several recommendations are made for future programs.

  14. Algal biomass and pigments along a latitudinal gradient in Victoria Land lakes, East Antarctica

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    Francesca Borghini

    2016-05-01

    Full Text Available It is generally accepted that Antarctic terrestrial diversity decreases as latitude increases, but latitudinal patterns of several organisms are not always as clear as expected. The Victoria Land region is rich in lakes and ponds and spans 8 degrees of latitude that encompasses gradients in factors such as solar radiation, temperature, ice cover and day length. An understanding of the links between latitudinally driven environmental and biodiversity changes is essential to the understanding of the ecology and evolution of Antarctic biota and the formulation of hypotheses about likely future changes in biodiversity. As several studies have demonstrated that photosynthetic pigments are an excellent, although underused, tool for the study of lacustrine algal communities, the aim of the present study was to investigate variations in algal biomass and biodiversity across the latitudinal gradient of Victoria Land using sedimentary pigments. We test the hypothesis that the biodiversity of freshwater environments decreases as latitude increases. On the basis of our results, we propose using the number of sedimentary pigments as a proxy for algal diversity and the sum of chlorophyll a and bacteriochlorophyll a with their degradation derivatives as an index of biomass. Overall, our data show that biomass and diversity decrease as latitude increases but local environmental conditions, in particular, natural levels of eutrophy, can affect both productivity and diversity.

  15. Performance of 119 Brazilian children on Stroop paradigm: Victoria version Desempenho de 119 crianças brasileiras no paradigma Stroop: versão Victoria

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    Helenice Charchat-Fichman

    2009-06-01

    Full Text Available BACKGROUND: The Stroop paradigm evaluates susceptibility to interference and is sensitive to dysfunction in frontal lobes. Performance in the Stroop changes along the development. Despite its usefulness in research and clinical settings, there are few studies with Brazilian samples. OBJECTIVE: This study investigates the performance and age effect on Stroop paradigm of Brazilian children. METHOD: A sample of 119 children, aged from 7 to 10 years, was submitted to the Victoria version of Stroop. RESULTS: The pattern of results observed was similar to that observed in foreign studies with adults and children. Younger children were overall slower than older ones (positive correlation between age and naming time. Also, younger children showed more susceptible to interference than older ones (negative correlation between age and number of errors for the maximal interference condition. CONCLUSION: There was an age effect explained in terms of developmental changes in information processing velocity and attention selectivity.INTRODUÇÃO: O paradigma Stroop avalia a susceptibilidade à interferência e é sensível a disfunção nos lobos frontais. O desempenho no Stroop muda durante o desenvolvimento. Apesar de sua utilidade na pesquisa e na clínica, existem poucos estudos brasileiros. OBJETIVO: Investigar o desempenho e efeito de idade de crianças brasileiras no Stroop. MÉTODO: A versão Victoria do Stroop foi aplicada em 119 crianças (7 a 10 anos. RESULTADOS: O padrão de resultados observado é comparável a estudos estrangeiros com adultos e crianças. Crianças mais jovens foram mais lentas do que as mais velhas (correlação positiva entre idade e tempo de nomeação. Os mais jovens apresentaram maior susceptibilidade à interferência, comparados aos mais velhos (correlação negativa entre idade e número de erros para a condição de interferência máxima. CONCLUSÃO: O efeito de idade foi observado e discutido em termos de mudanças na

  16. One Fish, Two Fish, Red Fish, Blue Fish: Geography, Ecology, Sympatry, and Male Coloration in the Lake Malawi Cichlid Genus Labeotropheus (Perciformes: Cichlidae

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    Michael J. Pauers

    2011-01-01

    Full Text Available While sexual selection on male coloration has been important in haplochromine cichlid speciation, few studies to date have examined potential environmental influences on color pattern evolution. Data from multiple sources on male nuptial coloration of the Lake Malawi endemic genus Labeotropheus were used to examine the relationship between color patterns and the environments in which these patterns were found. Red- or carotenoid-pigmented males were concentrated in the northwestern portion of Lake Malawi and were also associated with increasing depth. Further, the presence or absence of L. fuelleborni influenced the coloration of L. trewavasae populations; when L. fuelleborni was present, L. trewavasae males were more likely to exhibit some degree of red coloration. While these results support the idea that sexual selection on male coloration is an important factor in the haplochromine speciation, they also underscore the importance of environmental influences on the evolution of color patterns.

  17. Aggressive interactions between the invasive Rio Grande cichlid (Herichthys cyanoguttatus) and native bluegill (Lepomis macrochirus), with notes on redspotted sunfish (Lepomis miniatus)

    Science.gov (United States)

    Lorenz, O. Thomas; O' Connell, Martin T.; Schofield, Pamela J.

    2010-01-01

    The Rio Grande cichlid (Herichthys cyanoguttatus) has been established in the Greater New Orleans Metropolitan area for at least 20 years, and its effect on native fishes is unknown. Behavioral trials were performed to determine if aggressive interactions occur between invasive H. cyanoguttatus and native bluegill (Lepomis macrochirus). When defending a territory as the resident, L. macrochirus were markedly aggressive, averaging 11.6 aggressive actions per lO-min behavioral trial. In contrast, L. macrochirus were extremely passive as invaders, with 0.5 aggressive actions per trial. Herichthys cyanoguttatus were equally aggressive as residents and as invaders, averaging 4.9 and 6.0 aggressive actions per trial, respectively. Herichthys cyanoguttatus interacted aggressively with native species whether they held territory or not, indicating that this invasive species may have fundamentally different strategies of aggression compared with native L. macrochirus. These differences may explain the continued success of H. cyanoguttatus as an invasive fish in southeastern Louisiana.

  18. A gene expression study of dorso-ventrally restricted pigment pattern in adult fins of Neolamprologus meeli, an African cichlid species

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    Ehsan Pashay Ahi

    2017-01-01

    Full Text Available Fish color patterns are among the most diverse phenotypic traits found in the animal kingdom. Understanding the molecular and cellular mechanisms that control in chromatophore distribution and pigmentation underlying this diversity is a major goal in developmental and evolutionary biology, which has predominantly been pursued in the zebrafish model system. Here, we apply results from zebrafish work to study a naturally occurring color pattern phenotype in the fins of an African cichlid species from Lake Tanganyika. The cichlid fish Neolamprologus meeli displays a distinct dorsal color pattern, with black and white stripes along the edges of the dorsal fin and of the dorsal half of the caudal fin, corresponding with differences in melanophore density. To elucidate the molecular mechanisms controlling the differences in dorsal and ventral color patterning in the fins, we quantitatively assessed the expression of 15 candidate target genes involved in adult zebrafish pigmentation and stripe formation. For reference gene validation, we screened the expression stability of seven widely expressed genes across the investigated tissue samples and identified tbp as appropriate reference. Relative expression levels of the candidate target genes were compared between the dorsal, striped fin regions and the corresponding uniform, grey-colored regions in the anal and ventral caudal fin. Dorso-ventral expression differences, with elevated levels in both white and black stripes, were observed in two genes, the melanosome protein coding gene pmel and in igsf11, which affects melanophore adhesion, migration and survival. Next, we predicted potential shared upstream regulators of pmel and igsf11. Testing the expression patterns of six predicted transcriptions factors revealed dorso-ventral expression difference of irf1 and significant, negative expression correlation of irf1 with both pmel and igsf11. Based on these results, we propose pmel, igsf11 and irf1 as

  19. Dietary habits of juveniles of the Mayan cichlid, Cichlasoma urophthalmus, in mangrove ponds of an offshore islet in Belize, Central America

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    Amandine Vaslet

    Full Text Available Foraging habitats of juveniles of the Mayan cichlid, Cichlasoma urophthalmus (Günther, 1862, were investigated in two mangrove ponds located in Twin Cays offshore islet in Belize: Sink Hole pond (SH and Hidden Lake pond (HL. Sink Hole pond is a semiclosed body of water, whereas Hidden Lake pond is connected by a channel to adjacent seagrass beds that surround the islet. Gut contents of 21 juvenile C. urophthalmus (9.8-13.2 cm total length were analyzed, and five prey taxa were identified. In both mangrove ponds, C. urophthalmus were opportunistic carnivores and consumed primarily crustaceans. Plant material and detritus present in gut contents were most likely ingested incidentally when the fish foraged on small invertebrates. Carbon isotopic values of fish specimens from the two ponds were similar (mean ± SD of -19.2 ± 0.4‰ in SH and -19.4 ± 0.4‰ in HL, and were close to those of mangrove prey (mean ± SD = -20.2 ± 1.5‰, suggesting that this fish species forages in this habitat. Mixing models showed a higher contribution of mangrove food sources to the fish diet than seagrass food sources. This study reveals that young Mayan cichlids, inhabiting two Belize mangrove ponds, are generalists and opportunistic carnivores that forage on mangrove food sources and do not appear to move to adjacent seagrass beds to complement their diets. Understanding trophic linkages between aquatic consumers and food resources may contribute to better management of threatened coastal ecosystems.

  20. Three Decades of Implementation of School-Based Management in the Australian Capital Territory and Victoria in Australia

    Science.gov (United States)

    Gammage, David T.

    2008-01-01

    Purpose: The purpose of this paper is to explore how the process of implementation of school-based management (SBM) has worked within the public school systems in the Australian Capital Territory (ACT) and Victoria in Australia. The period covered was 1976-2006. Design/methodology/approach: The approach adopted was the mixed methodology which…

  1. Language in the Workplace Project and Workplace Communication for Skilled Migrants Course at Victoria University of Wellington, New Zealand

    Science.gov (United States)

    de Bres, Julia; Holmes, Janet; Joe, Angela; Marra, Meredith; Newton, Jonathan; Riddiford Nicky; Vine, Bernadette

    2009-01-01

    The School of Linguistics and Applied Language Studies (LALS) at Victoria University of Wellington conducts research and teaching in Linguistics, Applied Linguistics, Writing and Deaf Studies. It incorporates a Deaf Studies Research Unit, which undertakes research on topics relating to deaf people and their language in New Zealand, and the New…

  2. University of Victoria Genome British Columbia Proteomics Centre Partners with CPTAC | Office of Cancer Clinical Proteomics Research

    Science.gov (United States)

    University of Victoria Genome British Columbia Proteomics Centre, a leader in proteomic technology development, has partnered with the U.S. National Cancer Institute (NCI) to make targeted proteomic assays accessible to the community through NCI’s CPTAC Assay Portal (https://assays.cancer.gov).

  3. Possible implications of Rabbit Calicivirus Disease for malleefowl Leipoa ocellata Gould in the north-west of Victoria

    NARCIS (Netherlands)

    Sandell, P.

    1999-01-01

    Parks Victoria and the Department of Natural Resources & Environment (NRE) are collaborating with agencies from the other States and the Commonwealth of Australia in a national program of detailed monitoring and surveillance of the effects of Rabbit Calicivirus Disease (RCD). A component of the

  4. Victoria Khiterer. Jewish City or Inferno of Russian Israel? A History of the Jews in Kiev Before February 1917.

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    Kimberly St. Julian-Varnon

    2017-09-01

    Full Text Available Book review of Victoria Khiterer. Jewish City or Inferno of Russian Israel? A History of the Jews in Kiev Before February 1917. Academic Studies Press, 2016. Jews of Russia and Eastern Europe and Their Legacy, series editor, Maxim D. Shrayer. xx, 474 pp. Illustrations. Tables. Maps. Appendix. Bibliography. Index. $89.00, cloth.

  5. The Development and Use of Individual Learning Plans for Deaf and Hard of Hearing Students in Victoria, Australia

    Science.gov (United States)

    Brown, P. Margaret; Byrnes, Linda J.

    2014-01-01

    This study investigated the Individual Learning Plans of eighty-eight students who were deaf and hard of hearing attending facilities and schools for the deaf in Victoria Australia. The students' assessment and planning portfolios were scrutinised for evidence of formal and informal assessment used to generate goals for the Individual Learning…

  6. Chequered fortunes in global exports: The sociogenesis of African entrepreneurship in the Nile Perch Business at Lake Victoria, Uganda

    NARCIS (Netherlands)

    Beuving, J.J.

    2013-01-01

    This article looks at African entrepreneurship in the Nile perch export business at Lake Victoria, Uganda. Often heralded as an economic success story, this business has perhaps another tale to tell. The fishermen, traders and other small-scale entrepreneurs at the lower end of the export chain face

  7. Poética de la autotraducción: María Victoria Atencia

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    López Martínez, María Isabel

    2015-12-01

    Full Text Available Self-translation is an ancient but poorly researched practice. This article analyses an exceptional case: the reflection on self-translation as exposed in poetry. A case in point is the poem «Voz traducida», from the poetry collection De la llama en que arde (1988. Indeed, the poem selected for examination was written by M.ª Victoria Atencia (Málaga, 1931, an expert both in writing poetry and in translating literature. Her book of poems also contains an original text, «Rosas», in Galician, and its corresponding Spanish translation. Both translation and reflection are complementary in her compositions. These poetic creations attest to the fact that artfulness works as a depiction of the next creation. Furthermore, this study will deeply explore the poet’s most important literary thoughts.La autotraducción es una práctica antigua, pero poco estudiada. El presente artículo analiza un caso excepcional: la reflexión sobre la autotraducción expuesta en la lírica. Para ello, se analiza el poema de M.ª Victoria Atencia «Voz traducida», perteneciente al libro titulado De la llama en que arde (1988. Es un ejemplo de que la tarea de traducir funciona como un motivo que origina una nueva creación. Además, permite que el lector conozca facetas importantes del pensamiento literario de la escritora. M.ª Victoria Atencia, además de poeta, es una experta traductora. El libro contiene también dos versiones del poema «Rosas», en gallego y en español, pruebas de la dimensión práctica de los planteamientos teóricos de la autora y de su coherencia estética. Ambas facetas, la traducción y la reflexión, son complementarias en la obra de la autora.

  8. Characteristics of potential gasifier fuels in selected regions of the Lake Victoria Basin

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    Geoffrey O. Mosiori

    2015-05-01

    Full Text Available All countries in the Lake Victoria Basin depend mostly on hydroelectric power for the provision of energy. Gasification technology has a high potential for reducing biomass energy consumption whilst increasing access to modern energy services. The key aspect for the failure of gasification operations in the Lake Victoria Basin is inadequate adaptation of gasification equipment to fuel characteristics, lack of fuel specification and inappropriate material choice. We therefore investigated the thermo-chemical characterisation of six biomass fuels, namely Pinus caribaea, Calitris robusta, Cupressus lusitanica, Eucalyptus grandis, Pinus patula and sugarcane bagasse from selected regions of the Lake Victoria Basin. Ultimate analysis was done using a Flash 2000 elemental analyser. Moisture content, ash content and volatile matter were determined in oven and muffle furnaces while heating values were determined using a Gallenkamp calorimeter. The mean percentage levels obtained indicate that all six biomass fuels had a mean range for nitrogen of 0.07±0.2–0.25±0.07%, for carbon of 40.45±0.61–48.88±0.29%, for hydrogen of 4.32±0.13–5.59±0.18% and for oxygen of 43.41±1.58–51.1±0.64%. Moisture content ranged between 25.74±1.54% and 56.69±0.52%, ash content between 0.38±0.02% and 2.94±0.14%, volatile matter between 74.68±0.49% and 82.71±0.19% and fixed carbon between 14.35±0.33% and 24.74±0.27%. Heating values ranged between 16.95±0.10 MJ/kg and 19.48±0.42 MJ/kg. The results suggest that all six biomass fuels are potential biomass gasification materials.

  9. Extent and drainage status of organic soils in the Lake Victoria catchment

    Science.gov (United States)

    Barthelmes, Reni; Barthelmes, Alexandra; Joosten, Hans

    2016-04-01

    When considering peatlands and organic soils in the tropics, the huge areas in SE Asia prevail in public and scientific perception, whereas Africa has largely been out of focus. However, East Africa contains large areas of organic soils as well. They basically occur in the high altitudes of the uplifted flanks of the East African Rift System, isolated volcanoes and the Ethiopian highlands, in the Zambezian floodplains (e.g. Zambia), and in coastal environments (e.g. Mozambique and Madagascar). We used a mapping approach that integrates old field data and maps, specialized landscape and peatland-related knowledge, and modern RS and GIS techniques to elaborate a comprehensive and rather reliable overview of organic soils (incl. peatlands) in the Lake Victoria catchment. Maps at a scale of 1:25,000 have been prepared for Burundi, Kenya, Rwanda, Tanzania and Uganda. The land use intensity has been estimated for all organic soil areas based on satellite and aerial imagery. Feeding the Nile River, sustaining a fast growing and widely poor population and already facing climatic changes, organic soils of the Lake Victoria neighbouring countries are partially under heavy threat. We mapped 10,645 km2 of organic soils for the entire area of which 8,860 km2 (83.2%) seem to be in near natural condition. We assume slightly drainage and low degradation for 564 km2 (5.3%) and intensive drainage and heavy degradation for 1,222 km2 (11.5%). Degradation hotspot is Burundi with 522 km2 (79.5%) of heavily drained and degrading organic soils. This area assessment has been quite conservative to not overestimate the extent of organic soils. A reserve of 5-7,000 km2 of wetlands in the Lake Victoria catchment may include peatlands too, which needs to be confirmed in field surveys. Considering the key role of peatlands and organic soils for water provision and regulation and their rapid degradation due to drainage and inappropriate use, this inventory might be a step towards organic soil

  10. Temperature and hydrologic variability of Lake Victoria, East Africa since the Late Pleistocene

    Science.gov (United States)

    Berke, M. A.; Johnson, T. C.; Werne, J. P.; Schouten, S.; Sinninghe Damste, J. S.

    2010-12-01

    Recent organic geochemical advances have facilitated the comparison between continental temperature change and hydrologic variability. TEX86, a proxy based on the lipids of aquatic Crenarchaeota that show a positive correlation with growth temperature, was used to reconstruct surface water temperatures from Lake Victoria, East Africa during the latest Pleistocene-Holocene. Hydrologic conditions were interpreted using paleoecological implications of shifting pollen and diatom assemblages found in the lake (Kendall, 1969; Stager et al., 2003) and will be compared with future compound specific δ13C data from terrestrial biomarkers in order to determine the patterns of rainfall and aridity in this region. Initial comparisons of climatic changes seen in temperature and hydrologic records appear to show consistency between warm/wet intervals and cool/dry intervals that is often assumed, but more rarely shown, in tropical Africa. Lake Victoria temperatures show a steady warming beginning 16 cal ka, with a pause around the Younger Dryas, dominated by arid conditions and strong savannah grassland development during this interval. There is continued warming to a sustained thermal maximum for this portion of the record at ~10.5-8.5 ka, which generally coincides with the beginning of the Holocene Hypsithermal, an interval of elevated temperatures and precipitation throughout much of tropical Africa. This thermal maximum occurs during the most humid interval of this record (~9.5-8.3 ka), shown by an increase of humid forest pollen and high diatom abundance (due to increased water column mixing and nutrient runoff). Temperatures abruptly cool ~1.5°C in <800 years while precipitation becomes somewhat more seasonally restricted, coinciding with an abrupt drop in inferred P:E ratio and reduction in wind-driven mixing. The record then shows a general cooling, reaching a Holocene thermal minimum of ~18.4°C at ~4.5 ka, contrary to other East African continental and marine

  11. The Meaning of ‘General Paralysis of the Insane’ in Victoria, Australia; 1886 to 1906

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    Roberts, Phillip

    2014-06-01

    Full Text Available This paper presents a conclusion to the meaning of the historical diagnosis “general paralysis of the insane” in nineteenth century Victorian Registrar General”s reports. Most studies suggest that in the past the diagnosis refers to neuro-syphilis, and while after 1906 this is not disputed, this paper will show that the diagnosis had a much broader meaning incorporating many forms of degenerative brain disease during the study period (Victoria 1886 to 1906. It is acknowledged, however, that the use of this diagnosis may have varied dramatically in the past based on a doctor’s education and/or background. This conclusion has been arrived at by analysing both government and general hospital records on the Australian, Victorian population. This paper also presents methods for determining the meaning of obsolete medical diagnoses where the definition is poorly understood.En este trabajo presenta una conclusión sobre el significado de la “parálisis general de los locos” como diagnóstico en los informes del Victorian Registrar General durante el siglo XIX. La mayoría de los estudios sugieren que en el pasado el diagnóstico se refiere a la neuro-sífilis, y aunque después de 1906 no se discute, este trabajo mostrará que el diagnóstico tiene un significado mucho más amplio e incorpora muchas formas de enfermedad degenerativa del cerebro durante el período de estudio (Victoria 1886 a 1906. Se reconoce, sin embargo, que el uso de este diagnóstico puede haber variado drásticamente en el pasado dependiendo de la formación y del ambiente médico. Se ha llegado a esta conclusión mediante el análisis de los registros hospitalarios de la población de Victoria, Australia. Este documento también presenta métodos para determinar el significado de los diagnósticos médicos obsoletos cuya definición es confusa.

  12. Residual susceptibility to measles among young adults in Victoria, Australia following a national targeted measles-mumps-rubella vaccination campaign

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    Leydon Jennie A

    2007-06-01

    Full Text Available Abstract Background Past measles immunisation policies in Australia have resulted in a cohort of young adults who have been inadequately vaccinated, but who also have low levels of naturally acquired immunity because immunisation programs have decreased the circulation of wild virus. A measles-mumps-rubella (MMR immunisation campaign aimed at addressing this susceptibility to measles among young adults was conducted in Australia in 2001–2. By estimating age-specific immunity, we aimed to evaluate the success of this campaign in the state of Victoria. Methods We conducted serosurveys after the young adult MMR program at state and national levels to estimate immunity among young adults born between 1968–82. We compared results of the Victorian (state surveys with the Victorian component of the national surveys and compared both surveys with surveys conducted before the campaign. We also reviewed all laboratory confirmed measles cases in Victoria between 2000–4. Results The Victorian state serosurveys indicated no significant change in immunity of the cohort following the young adult MMR campaign (83.9% immune pre and 85.5% immune post campaign while the Victorian component of the national serosurvey indicated a significant decline in immunity (91.0% to 84.2%; p = 0.006. Both surveys indicated about 15% susceptibility to measles among young Victorian adults after the campaign. Measles outbreaks in Victoria between 2000–4 confirmed the susceptibility of young adults. Outbreaks involved a median of 2.5 cases with a median age of 24.5 years. Conclusion In Victoria, the young adult MMR program appears to have had no effect on residual susceptibility to measles among the 1968–82 birth cohort. Young adults in Victoria, as in other countries where past immunisation policies have left a residual susceptible cohort, represent a potential problem for the maintenance of measles elimination.

  13. LAKE VICTORIA AND THE COMMON PROPERTY DEBATE: IS THE TRAGEDY OF THE COMMONS A THREAT TO ITS FUTURE?

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    Erick Ochieng OGELLO

    2013-12-01

    Full Text Available Lake Victoria is the largest among the African Great Lakes in East African region that are believed to have both dynamic and fragile aquatic ecosystems. Within two decades, the lake has experienced extensive resource exploitation leading to constrained productivity and drastic decline of native biodiversity. Intensive non-selective fishing, catchment vegetation degradation, industrial and agricultural pollution, the introduction of exotic species and uneven patchwork of governmental laws are some of the reasons for the current ecological woes facing Lake Victoria. This paper intends to stimulate recognition of Lake Victoria and its catchment as a lived Com­mons, to be shared, protected, managed and enjoyed by all who live around it. The paper compares the original biodiversity status of the lake with the current status and discusses the role of unlimited access as a function of the loss of the Lake’s biological wealth. The Lake’s water resource base, fishery, wetlands and other aquatic resources have been exhaustively discussed. In this review, we uphold the Hardin’s school of thought that freedom of the commoners causes resource overuse leading to poverty. Therefore, limiting freedom could be essential. However, there is need for provision of alternative means of survival since people with no choices would continue over-exploiting ecosystems even under limited access. The Lake Victoria basin commons should be protected by strict legal and clear political frame­work based on public trust doctrine, reinforced in law that the Lake is vital for the survival of people, plants and animals living on or near it and therefore must be protected for the common good. The political jurisdictions should consider governing the Lake basin as one integrated watershed. It is our fervent hope that bordering communities will secure grass root movements to protect and nurture Lake Victoria and its environs for the benefit of the present and future

  14. Seismicity and arrival-time residuals from the Victoria Earthquake of June 9, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Wong, V.; Frez, J.

    1981-01-01

    Hypocenter distribution in space and time of the aftershock activity from the Victoria Earthquake of June 9, 1980 was studied. It was concluded that the main event excited aftershocks in several pre-existing nests at the northwest end of the Cerro Prieto Fault, but no significant activity occurred at the immediate neighborhood of the main event. The depth of the aftershocks increases with the distance from the northwest end of the fault and this feature might be related with the higher temperatures and the spreading center located between the ends of the Imperial and Cerro Prieto Faults. The significance of the arrival-times residuals for local and regional stations is discussed both for P and S-waves and the importance of obtaining station corrections is emphasized. The non-uniqueness in determining a structure which minimizes the residuals is illustrated. Two different structures which satisfy the local data are presented.

  15. Journalist to the interview: professionals routines. The case of Ciudad Victoria, Tamaulipas, México

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    Carlos David SANTAMARÍA OCHOA

    2014-10-01

    Full Text Available The newspaper interview is sort of use in printed newspapers in Ciudad Victoria Tamaulipas, Mexico. Journalists argue lack of time-space and is to develop this type of work. An analysis of the publications of the largest newspapers in this city dad throws the result that no literary interviews are published, the em-ployee's resource for structuring news and sporadically of reports. This paper develops conducting depth interviews with journalists pe-active, which reaffirm the limited use given the corresponding gender, as well as an analysis of the works published in newspapers printed cases in the capital of Tamaulipas, only on local information section. Lack of time for preparation, few spaces and I shift to electronic means are the most common causes.

  16. Compliance with regulations by "swim-with-dolphins" operations in Port Phillip Bay, Victoria, Australia.

    Science.gov (United States)

    Scarpaci, Carol; Dayanthi, Nugegoda; Corkeron, Peter J

    2003-03-01

    Managing the activities of commercial wildlife viewing tends to involve either restricting the number of industry participants and/or regulating the activities or industry participants. We report on operator compliance with regulations regarding humans swimming with free-ranging bottlenose dolphins ( Tursiops sp.) in Port Phillip Bay, Victoria, Australia. A total of 128 commercial dolphin-swim trips was studied between September 1998 and April 2000. Four permit conditions were investigated: approach type, swim time, time in proximity of dolphins, and presence of "fetal fold" calves. Results demonstrate noncompliance by operators to all of the four permit conditions studied. Compliance with temporal conditions was poorer than with other conditions. When conducting studies on the extent to which tourism affects cetaceans, investigators should consider whether tourist operations comply with existing regulations or guidelines.

  17. Suffering by comparison: Twitter users' reactions to the Victoria's Secret Fashion Show.

    Science.gov (United States)

    Chrisler, Joan C; Fung, Kaitlin T; Lopez, Alexandra M; Gorman, Jennifer A

    2013-09-01

    Social comparison theory suggests that evaluating the self in comparison with others (e.g., peers, celebrities, models) can influence body image. Experimental studies that have tested effects of viewing idealized images in the media often show that women feel worse about themselves after seeing images that illustrate the beauty ideal. Twitter presents a naturally occurring opportunity to study viewers' reactions. An analysis was conducted of 977 tweets sent immediately before and during the 2011 Victoria's Secret Fashion Show that reference the show. Although the majority were idiosyncratic remarks, many tweets contain evidence of upward social comparisons to the fashion models. There were tweets about body image, eating disorders, weight, desires for food or alcohol, and thoughts about self-harm. The results support social comparison theory, and suggest that vulnerable viewers could experience negative affect, or even engage in harmful behaviors, during or after viewing the show or others like it. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Environmental factors associated with the foliage cover of invasive fairy grass (Lachnagrostis filiformis) in Victoria, Australia.

    Science.gov (United States)

    Gosney, Kate; Florentine, Singarayer K

    2018-01-01

    Fairy grass (Lachnagrostis filiformis) is an Australian native grass that has recently become a major concern for rural communities. Its dried inflorescences are blown by the wind and build up against fences and buildings, becoming a severe fire hazard. Understanding the ecology of fairy grass and its impacts on rural communities is relevant to its management. Four dry lake beds in Western Victoria were selected to determine if environmental factors, such as lake, location, direction, altitude and road type and the covariates of pH, soil salinity, soil moisture and distance to nearest road, are related to the presence of fairy grass. The 'lake' factor was the only environmental parameter that was significantly associated with the presence of this weed.

  19. Fine resolution AMS {sup 14}C chronology for Lunette-Lake sediment sequences, Lake Bolac, Victoria

    Energy Technology Data Exchange (ETDEWEB)

    Cook, E. [Monash University, Clayton, VIC (Australia). Centre for Palynology and Palaeoecology, Department of Geography and Environmental Science

    1998-12-31

    This study aims to provide a fine-resolution chronology for lake sediment records from Lakes Bolac and Turangmoroke, located within the drier part of the Western Plains, Victoria. These lakes are expected to be sensitive to subtle climate and vegetation variability and have long been recognised as archaeologically rich, bearing stone tools, hearth and other cultural materials dated to the late Pleistocene (Horton, 1984; former Victorian Aboriginal Survey, unpublished data). Fine-resolution chronological control has rarely been attempted in this sedimentary and (semi-arid) climatic context owing to the paucity of material available for conventional {sup 14}C dating. However, pollen and microscopic charcoal in the lake sediments at Bolac and Turangmoroke are suitable for AMS age determination with the most important sedimentary section well within the range of {sup 14}C making them ideal records for such a study. Recent dating results, which have substantially increased chronostratigraphic interpretation of concurrent palaeoecological and sedimentological work in progress, are presented

  20. PREDICTION OF THE LIKELIHOOD OF HOUSEHOLDS FOOD SECURITY IN THE LAKE VICTORIA REGION OF KENYA

    Directory of Open Access Journals (Sweden)

    Peter Nyamuhanga Mwita

    2011-06-01

    Full Text Available This paper considers the modeling and prediction of  households food security status using a sample of households in the  Lake Victoria region of Kenya. A priori expected food security  factors and their measurements are given. A binary logistic regression model  derived was fitted to thirteen priori expected factors. Analysis of the marginal effects revealed that effecting the use of the seven significant determinants: farmland size, per capita aggregate production, household size, gender of household head, use of fertilizer, use of pesticide/herbicide and education of household head,  increase the likelihood of a household being food secure. Finally, interpretations  of   predicted conditional probabilities, following improvement of significant determinants,  are given.

  1. Reality check of laboratory service effectiveness during pandemic (H1N1) 2009, Victoria, Australia.

    Science.gov (United States)

    Catton, Michael; Druce, Julian; Papadakis, Goergina; Tran, Thomas; Birch, Christopher

    2011-06-01

    In Australia, the outbreak of pandemic (H1N1) 2009 began in Melbourne, Victoria; in the first 17 days, the Victorian Infectious Diseases Reference Laboratory detected 977 cases. Although the laboratory had a pandemic plan in place, a retrospective evaluation found 3 major variations from plan assumptions: 1) higher peak demand not limited by a case definition, 2) prolonged peak demand because containment attempts continued despite widespread influenza, and 3) unexpected influence of negative test results on public health actions. Although implementation of the plan was generally successful, the greatest challenges were limited availability of skilled staff and test reagents. Despite peak demand of 1,401 tests per day, results were provided within the usual 24 hours of specimen receipt; however, turnaround time seemed slower because of slow transport times (>3 days for 45% of specimens). Hence, effective laboratory capability might be enhanced by speeding transport of specimens and improving transmission of clinical data.

  2. La legobiografía de Victoria Ocampo: evocaciones de una lectora (des)autorizada

    OpenAIRE

    Vélez, Irma

    2012-01-01

    Pero no conseguiré hacer nada en el campo de la novela. Tengo que escribir à batons rompus, cuando se me antoje. Jamás podré crear un personaje. Lo llevaría a la rastra, y eso no sirve. Y todos mis personajes serían “yo” disfrazada. Perfectamente insoportable. ¿Cómo demonios puede uno deshacerse de su “yo” ?(Fragmento de Carta a Delfina Bunge, Autobiografía II, p. 85)En 1910, Victoria Ocampo cumple 20 años, apenas dos años después que en Santiago se auspiciara la sede del Primer Congreso Cien...

  3. La legobiografía de Victoria Ocampo: evocaciones de una lectora (desautorizada

    Directory of Open Access Journals (Sweden)

    Irma Vélez

    2006-07-01

    Full Text Available Pero no conseguiré hacer nada en el campo de la novela. Tengo que escribir à batons rompus, cuando se me antoje. Jamás podré crear un personaje. Lo llevaría a la rastra, y eso no sirve. Y todos mis personajes serían “yo” disfrazada. Perfectamente insoportable. ¿Cómo demonios puede uno deshacerse de su “yo” ?(Fragmento de Carta a Delfina Bunge, Autobiografía II, p. 85En 1910, Victoria Ocampo cumple 20 años, apenas dos años después que en Santiago se auspiciara la sede del Primer Congreso Cien...

  4. Coupled human and natural system dynamics as key to the sustainability of Lake Victoria's ecosystem services

    Directory of Open Access Journals (Sweden)

    Andrea S. Downing

    2014-12-01

    Full Text Available East Africa's Lake Victoria provides resources and services to millions of people on the lake's shores and abroad. In particular, the lake's fisheries are an important source of protein, employment, and international economic connections for the whole region. Nonetheless, stock dynamics are poorly understood and currently unpredictable. Furthermore, fishery dynamics are intricately connected to other supporting services of the lake as well as to lakeshore societies and economies. Much research has been carried out piecemeal on different aspects of Lake Victoria's system; e.g., societies, biodiversity, fisheries, and eutrophication. However, to disentangle drivers and dynamics of change in this complex system, we need to put these pieces together and analyze the system as a whole. We did so by first building a qualitative model of the lake's social-ecological system. We then investigated the model system through a qualitative loop analysis, and finally examined effects of changes on the system state and structure. The model and its contextual analysis allowed us to investigate system-wide chain reactions resulting from disturbances. Importantly, we built a tool that can be used to analyze the cascading effects of management options and establish the requirements for their success. We found that high connectedness of the system at the exploitation level, through fisheries having multiple target stocks, can increase the stocks' vulnerability to exploitation but reduce society's vulnerability to variability in individual stocks. We describe how there are multiple pathways to any change in the system, which makes it difficult to identify the root cause of changes but also broadens the management toolkit. Also, we illustrate how nutrient enrichment is not a self-regulating process, and that explicit management is necessary to halt or reverse eutrophication. This model is simple and usable to assess system-wide effects of management policies, and can

  5. Maternal and Child Health Nurses work with refugee families: Perspectives from regional Victoria, Australia.

    Science.gov (United States)

    Willey, Suzanne M; Cant, Robyn P; Williams, Allison; McIntyre, Meredith

    2018-01-21

    This study aimed to explore service provision for Victorian regional refugee families from the perspective of Maternal and Child Health nurses. Increasingly, more families from a refugee background are resettling in regional Victoria. The refugee journey has significant effect on families. Refugee families with infants and young children can be provided with support by Maternal and Child Health services; however, many families experience barriers to ongoing engagement with this service. This descriptive study used focus group and questionnaire. A purposive sample of 26 Maternal and Child Health Nurses was drawn from six municipalities throughout regional Victoria, where higher numbers of people from a refugee background resettle. Six focus groups were held in 2014. Audio-recorded narratives were transcribed, prior to inductive thematic analysis. Participating nurses were experienced nurses, averaging 12 years in the service. Four major themes emerged: 'How to identify women from a refugee background'; 'The Maternal and Child Health nurse role when working with families from a refugee background'; 'Interpreting issues', and 'Access to other referral agencies'. Nurses worked to develop a relationship with families, attending to a complex mix of issues which were complicated by language barriers. Nurses found their role in supporting refugee families required additional time and more home visits. To provide best practice, Maternal and Child Health nurses need (i) ongoing professional development; (ii) time, flexibility, and creativity to build relationships with refugee families and (iii) better access to services that enhance communication, such as interpreting services and translated resources. Nurses require ongoing professional development to help them address the multifaceted needs of families of refugee background. With limited resources available in regional areas, accessing further education can be challenging. Distance education models and organisational

  6. Intended and unintended consequences of abortion law reform: perspectives of abortion experts in Victoria, Australia.

    Science.gov (United States)

    Keogh, L A; Newton, D; Bayly, C; McNamee, K; Hardiman, A; Webster, A; Bismark, M

    2017-01-01

    In Victoria, Australia, abortion was decriminalised in October 2008, bringing the law in line with clinical practice and community attitudes. We describe how experts in abortion service provision perceived the intent and subsequent impact of the 2008 Victorian abortion law reform. Experts in abortion provision in Victoria were recruited for a qualitative semi-structured interview about the 2008 law reform and its perceived impact, until saturation was reached. Nineteen experts from a range of health care settings and geographic locations were interviewed in 2014/2015. Thematic analysis was conducted to summarise participants' views. Abortion law reform, while a positive event, was perceived to have changed little about the provision of abortion. The views of participants can be categorised into: (1) goals that law reform was intended to address and that have been achieved; (2) intent or hopes of law reform that have not been achieved; (3) unintended consequences; (4) coincidences; and (5) unfinished business. All agreed that law reform had repositioned abortion as a health rather than legal issue, had shifted the power in decision making from doctors to women, and had increased clarity and safety for doctors. However, all described outstanding concerns; limited public provision of surgical abortion; reduced access to abortion after 20 weeks; ongoing stigma; lack of a state-wide strategy for equitable abortion provision; and an unsustainable workforce. Law reform, while positive, has failed to address a number of significant issues in abortion service provision, and may have even resulted in a 'lull' in action. 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/.

  7. Simulation of Lake Victoria Circulation Patterns Using the Regional Ocean Modeling System (ROMS).

    Science.gov (United States)

    Nyamweya, Chrispine; Desjardins, Christopher; Sigurdsson, Sven; Tomasson, Tumi; Taabu-Munyaho, Anthony; Sitoki, Lewis; Stefansson, Gunnar

    2016-01-01

    Lake Victoria provides important ecosystem services including transport, water for domestic and industrial uses and fisheries to about 33 million inhabitants in three East African countries. The lake plays an important role in modulating regional climate. Its thermodynamics and hydrodynamics are also influenced by prevailing climatic and weather conditions on diel, seasonal and annual scales. However, information on water temperature and circulation in the lake is limited in space and time. We use a Regional Oceanographic Model System (ROMS) to simulate these processes from 1st January 2000 to 31st December 2014. The model is based on real bathymetry, river runoff and atmospheric forcing data using the bulk flux algorithm. Simulations show that the water column exhibits annual cycles of thermo-stratification (September-May) and mixing (June-August). Surface water currents take different patterns ranging from a lake-wide northward flow to gyres that vary in size and number. An under flow exists that leads to the formation of upwelling and downwelling regions. Current velocities are highest at the center of the lake and on the western inshore waters indicating enhanced water circulation in those areas. However, there is little exchange of water between the major gulfs (especially Nyanza) and the open lake, a factor that could be responsible for the different water quality reported in those regions. Findings of the present study enhance understanding of the physical processes (temperature and currents) that have an effect on diel, seasonal, and annual variations in stratification, vertical mixing, inshore-offshore exchanges and fluxes of nutrients that ultimately influence the biotic distribution and trophic structure. For instance information on areas/timing of upwelling and vertical mixing obtained from this study will help predict locations/seasons of high primary production and ultimately fisheries productivity in Lake Victoria.

  8. The Green Dialysis Survey: Establishing a Baseline for Environmental Sustainability across Dialysis Facilities in Victoria, Australia.

    Science.gov (United States)

    Barraclough, Katherine A; Gleeson, Alice; Holt, Stephen G; Agar, John Wm

    2017-11-02

    The Green Dialysis Survey aimed to 1) establish a baseline for environmental sustainability (ES) across Victorian dialysis facilities, and 2) guide future initiatives to reduce the environmental impact of dialysis delivery. Nurse unit managers of all Victorian public dialysis facilities received an online link to the survey, which asked 107 questions relevant to the ES of dialysis services. Responses were received from 71/83 dialysis facilities in Victoria (86%), representing 628/660 dialysis chairs (95%). Low energy lighting was present in 13 facilities (18%), 18 (25%) recycled reverse osmosis water and 7 (10%) reported use of renewable energy. Fifty-six facilities (79%) performed comingled recycling but only 27 (38%) recycled polyvinyl chloride plastic. A minority educated staff in appropriate waste management (n=30;42%) or formally audited waste generation and segregation (n=19;27%). Forty-four (62%) provided secure bicycle parking but only 33 (46%) provided shower and changing facilities. There was limited use of tele- or video-conferencing to replace staff meetings (n=19;27%) or patient clinic visits (n=13;18%). A minority considered ES in procurement decisions (n=28;39%) and there was minimal preparedness to cope with climate change. Only 39 services (49%) confirmed an ES policy and few had ever formed a green group (n=14; 20%) or were currently undertaking a green project (n=8;11%). Only 15 facilities (21%) made formal efforts to raise awareness of ES. This survey provides a baseline for practices that potentially impact the environmental sustainability of dialysis units in Victoria, Australia. It also identifies achievable targets for attention. This article is protected by copyright. All rights reserved.

  9. Benthic macroinvertebrate community structure in Napoleon Gulf, Lake Victoria: effects of cage aquaculture in eutrophic lake.

    Science.gov (United States)

    Egessa, Robert; Pabire, Gandhi Willy; Ocaya, Henry

    2018-02-02

    An investigation was conducted on the macro-benthic fauna of the Napoleon Gulf in the northern part of Lake Victoria from March 2011 to December 2016 at the cage fish farm. The aim was to examine the likely impact of cage aquaculture on macro-benthic invertebrates. Cage aquaculture is now a common practice on Lake Victoria yet little is known about its long-term effect on macro-benthic faunal assemblages. Temporal variation indicated a general decline in annual faunal density at the farm area with corresponding stability at upstream (control) and downstream sites. Arthropods remained numerically dominant at the control and downstream sites. The percentage abundance of EPT (Ephemeroptera, Plecoptera, and Trichoptera) and Malacostraca was highest at the upstream and lowest at the farm area. The farm area which initially was dominated by molluscs became dominated by arthropods after 3 years. The decrease in density of molluscs at the farm area was attributed to the general decrease in density of two species: Bellamya unicolor (Gastropoda) and Corbicula africana (Bivalvia). These two species were initially abundant but showed decline within the farm area with corresponding stability at the upstream and downstream areas. Oligochaete annelids were more abundant within the farm area than at the upstream and downstream sites. These findings suggested that molluscs offered better prediction of the impact of cages on the environment than arthropods. Besides that, in a community dominated by pollution-tolerant organisms, the impact of aquaculture may not be immediate especially when organic loading from aquaculture is moderate.

  10. Sex workers can be screened too often: a cost-effectiveness analysis in Victoria, Australia.

    Science.gov (United States)

    Wilson, David P; Heymer, Kelly-Jean; Anderson, Jonathan; O'Connor, Jody; Harcourt, Christine; Donovan, Basil

    2010-04-01

    Commercial sex is licensed in Victoria, Australia such that sex workers are required to have regular tests for sexually transmitted infections (STIs). However, the incidence and prevalence of STIs in sex workers are very low, especially since there is almost universal condom use at work. We aimed to conduct a cost-effectiveness analysis of the financial cost of the testing policy versus the health benefits of averting the transmission of HIV, syphilis, chlamydia and gonorrhoea to clients. We developed a simple mathematical transmission model, informed by conservative parameter estimates from all available data, linked to a cost-effectiveness analysis. We estimated that under current testing rates, it costs over $A90,000 in screening costs for every chlamydia infection averted (and $A600,000 in screening costs for each quality-adjusted life year (QALY) saved) and over $A4,000,000 for every HIV infection averted ($A10,000,000 in screening costs for each QALY saved). At an assumed willingness to pay of $A50,000 per QALY gained, HIV testing should not be conducted less than approximately every 40 weeks and chlamydia testing approximately once per year; in comparison, current requirements are testing every 12 weeks for HIV and every 4 weeks for chlamydia. Mandatory screening of female sex workers at current testing frequencies is not cost-effective for the prevention of disease in their male clients. The current testing rate required of sex workers in Victoria is excessive. Screening intervals for sex workers should be based on local STI epidemiology and not locked by legislation.

  11. The job satisfaction of female sex workers working in licensed brothels in Victoria, Australia.

    Science.gov (United States)

    Bilardi, Jade E; Miller, Amanda; Hocking, Jane S; Keogh, Louise; Cummings, Rosey; Chen, Marcus Y; Bradshaw, Catriona S; Fairley, Christopher K

    2011-01-01

    Previous studies have examined sex workers' attitudes to work but not their levels of job satisfaction compared with other occupations. The job satisfaction levels and standards of living of sex workers in licensed brothels in Victoria were compared with Australian women. Responses to a questionnaire that included questions about sex work and their "most likely alternative job." Survey data was compared with identical questions from the Households, Income and Labour Dynamics in Australia Survey. A structured survey was undertaken with sex workers in Victoria attending a a sexual health service. Of the 112 sex workers who agreed to participate in the study, 85 (76%) completed the survey. The median years women had been working as sex workers was three (range 0.1-18). The main reasons women started sex work was because "they needed the money" (69%), were attracted to the flexible hours (44%) or had a particular goal in mind (43%). The two biggest concerns women had about sex work were their safety (65%) and the risk of sexually transmitted infections (65%). When compared with the median job satisfaction scores of Australian women working in sex workers' "most likely alternative jobs," 50% of sex workers reported a higher median satisfaction score for sex work in relation to hours worked, 47% in relation to flexibility, 43% in relation to total pay, 26% in relation to job security, 19% in relation to the work itself, and 25% in relation to overall job satisfaction. Women reported that they primarily do sex work for financial gain although a significant minority prefer it to other work they would be likely to do. These results should be interpreted in the context that the presence of personality disorders that are common among sex workers were not measured in this study. © 2010 International Society for Sexual Medicine.

  12. El periodista ante la entrevista: rutinas profesionales. El caso de Ciudad Victoria, Tamaulipas, México

    Directory of Open Access Journals (Sweden)

    Santamaría Ochoa, Carlos David

    2013-06-01

    Full Text Available En español: La entrevista periodística es un género en desuso en los diarios impresos de Ciudad Victoria Tamaulipas, México. Los periodistas argumentan falta de tiempo y espacio para desarrollar este tipo de trabajos.Un análisis de las publicaciones de los diarios de mayor circulación en esta ciudad arroja como resultado el que no se publican entrevistas literarias; el recurso es empleado para la estructuración de noticias y, esporádicamente, de reportajes.El presente trabajo se desarrolla realizando entrevistas a profundidad con periodistas en activo, los que reafirman el poco uso que se da al género correspondiente, así como un análisis de los trabajos publicados en los diarios impresos de la capital de Tamaulipas, únicamente en la sección de información local.Falta de tiempo para la preparación, pocos espacios y el cambio hacia los me-dios electrónicos son las causas más recurrentes. In english: The newspaper interview is sort of use in printed newspapers in Ciudad Victoria Tamaulipas, Mexico. Journalists argue lack of time-space and is to develop this type of work.An analysis of the publications of the largest newspapers in this city dad throws the result that no literary interviews are published, the em-ployee's resource for structuring news and sporadically of reports.This paper develops conducting depth interviews with journalists pe-active, which reaffirm the limited use given the corresponding gender, as well as an analysis of the works published in newspapers printed cases in the capital of Tamaulipas, only on local information section. Lack of time for preparation, few spaces and I shift to electronic means are the most common causes.

  13. Perceptions about interventions to control schistosomiasis among the Lake Victoria island communities of Koome, Uganda.

    Directory of Open Access Journals (Sweden)

    Richard E Sanya

    2017-10-01

    Full Text Available Praziquantel-based mass treatment is the main approach to controlling schistosomiasis mansoni in endemic areas. Interventions such as provision and use of safe water, minimising contact with infested water, disposal of stool in latrines and snail control provide key avenues to break the transmission cycle and can sustain the benefits of mass treatment in the long term. Efforts are also being made to develop a schistosomiasis vaccine which, if effective, might reduce the incidence of re-infection after treatment. However, any interventions deployed need to be acceptable to, and sustainable by, the target communities.In this qualitative study, we investigated the perceptions of six Lake Victoria island communities of Koome, Uganda, about interventions to control Schistosoma mansoni infection and their willingness to participate in Schistosoma vaccine trials. Thirty-two in-depth interviews, 12 key informant interviews and 10 focus group discussions were conducted. Data were analysed using a thematic content approach.Intestinal schistosomiasis was not regarded as a serious health problem because a mass treatment programme is in place. However, the communities lack safe water sources and latrines. Mass treatment with praziquantel, safe water supplies and use of toilets were deemed the most acceptable interventions by the participants. The communities are willing to participate in Schistosoma vaccine trials.Knowledge of a community's perception about interventions to control schistosomiasis can be valuable to policy makers and programme implementers intending to set up interventions co-managed by the community members. In this study, the views of the Lake Victoria island communities of Koome are presented. This study also provides data to guide further work on alternative interventions such as Schistosoma vaccine trials in these communities.

  14. Tsetse fly (G. f. fuscipes distribution in the Lake Victoria basin of Uganda.

    Directory of Open Access Journals (Sweden)

    Mugenyi Albert

    2015-04-01

    Full Text Available Tsetse flies transmit trypanosomes, the causative agent of human and animal African trypanosomiasis. The tsetse vector is extensively distributed across sub-Saharan Africa. Trypanosomiasis maintenance is determined by the interrelationship of three elements: vertebrate host, parasite and the vector responsible for transmission. Mapping the distribution and abundance of tsetse flies assists in predicting trypanosomiasis distributions and developing rational strategies for disease and vector control. Given scarce resources to carry out regular full scale field tsetse surveys to up-date existing tsetse maps, there is a need to devise inexpensive means for regularly obtaining dependable area-wide tsetse data to guide control activities. In this study we used spatial epidemiological modelling techniques (logistic regression involving 5000 field-based tsetse-data (G. f. fuscipes points over an area of 40,000 km2, with satellite-derived environmental surrogates composed of precipitation, temperature, land cover, normalised difference vegetation index (NDVI and elevation at the sub-national level. We used these extensive tsetse data to analyse the relationships between presence of tsetse (G. f. fuscipes and environmental variables. The strength of the results was enhanced through the application of a spatial autologistic regression model (SARM. Using the SARM we showed that the probability of tsetse presence increased with proportion of forest cover and riverine vegetation. The key outputs are a predictive tsetse distribution map for the Lake Victoria basin of Uganda and an improved understanding of the association between tsetse presence and environmental variables. The predicted spatial distribution of tsetse in the Lake Victoria basin of Uganda will provide significant new information to assist with the spatial targeting of tsetse and trypanosomiasis control.

  15. Tsetse fly (G. f. fuscipes) distribution in the Lake Victoria basin of Uganda.

    Science.gov (United States)

    Albert, Mugenyi; Wardrop, Nicola A; Atkinson, Peter M; Torr, Steve J; Welburn, Susan C

    2015-04-01

    Tsetse flies transmit trypanosomes, the causative agent of human and animal African trypanosomiasis. The tsetse vector is extensively distributed across sub-Saharan Africa. Trypanosomiasis maintenance is determined by the interrelationship of three elements: vertebrate host, parasite and the vector responsible for transmission. Mapping the distribution and abundance of tsetse flies assists in predicting trypanosomiasis distributions and developing rational strategies for disease and vector control. Given scarce resources to carry out regular full scale field tsetse surveys to up-date existing tsetse maps, there is a need to devise inexpensive means for regularly obtaining dependable area-wide tsetse data to guide control activities. In this study we used spatial epidemiological modelling techniques (logistic regression) involving 5000 field-based tsetse-data (G. f. fuscipes) points over an area of 40,000 km2, with satellite-derived environmental surrogates composed of precipitation, temperature, land cover, normalised difference vegetation index (NDVI) and elevation at the sub-national level. We used these extensive tsetse data to analyse the relationships between presence of tsetse (G. f. fuscipes) and environmental variables. The strength of the results was enhanced through the application of a spatial autologistic regression model (SARM). Using the SARM we showed that the probability of tsetse presence increased with proportion of forest cover and riverine vegetation. The key outputs are a predictive tsetse distribution map for the Lake Victoria basin of Uganda and an improved understanding of the association between tsetse presence and environmental variables. The predicted spatial distribution of tsetse in the Lake Victoria basin of Uganda will provide significant new information to assist with the spatial targeting of tsetse and trypanosomiasis control.

  16. The effect of an area-based intervention on breastfeeding rates in Victoria, Australia.

    Science.gov (United States)

    Kelaher, Margaret; Dunt, David; Feldman, Peter; Nolan, Andrea; Raban, Bridie

    2009-04-01

    Best Start is an area-based early childhood intervention where projects are developed and implemented through a community partnership. A core tenet of the initiative is that implementing projects through a partnership generates greater value than would be expected if projects were undertaken independently by partner members. In this study we examine whether: (1) Best Start is effective in increasing the proportion of infants being fully breastfed at 3 months and 6 months. (2) The quality of community partnerships is a potential mechanism for change. Best Start was implemented in Victoria, Australia. The study examined breastfeeding rates before and after Best Start in sites with Best Start breastfeeding projects compared to the rest of state. The relationship between partnership quality scores and breastfeeding percentages was also examined. Both analyses controlled for socioeconomic and demographic differences and clustering by area. Best Start targeted some of the most socially disadvantaged communities in Victoria. In the 3 years of its operation, the rates of fully breastfeeding at 3 months (OR 1.30, 95% CI 1.14-1.47) and 6 months (OR 1.33, 95% CI 1.1-1.61) increased in Best Start sites compared to the rest of the state. Quality of partnership scores was positively associated with increased percentages of fully breastfeeding (3 months=OR 1.03, 95% CI 1.01-1.06; 6 months=OR 1.03, 95% CI 0.98-1.08). These results suggest that area-based interventions are effective in increasing percentages of fully breastfeeding. The study also supported the idea that developing quality community partnerships had a positive influence on their success.

  17. Impact of an outright ban on the availability of commercial tanning services in Victoria, Australia.

    Science.gov (United States)

    Sinclair, C; Cleaves, N; Dunstone, K; Makin, J; Zouzounis, S

    2016-08-01

    Australian states have introduced an outright ban on commercial artificial tanning sunbeds. This was based on evidence from systematic reviews affirming a strong association between tanning bed use and increased risk of melanoma. The implementation of the ban provides an opportunity to assess the effectiveness of the legislation in preventing access to artificial UV radiation. Compliance with the ban has been enforced and monitored by government departments. We additionally monitored online tanning bed advertisements before and after the ban, showing a decline over time in the number of sunbeds advertised for sale on gumtree.com.au and ebay.com.au, from a peak of 115 advertisements in May 2014 to 50 or fewer per month from February 2015. There was also an increase in advertised price, with the percentage of sunbeds offered in Victoria on gumtree.com.au at higher than $2 000 increasing from around 25% between January and June 2014 to 65% in the quarter following the introduction of the ban. Advertisements on gumtree.com.au from individuals wishing to access a sunbed in a private home in Victoria increased from only isolated instances in the months immediately prior to the ban, to between 25 and 77 advertisements per month in the quarter following the ban. In summary, the introduction of an outright ban of commercial sunbeds has achieved a dramatic reduction in the availability of harmful artificial UV radiation sources in Australia. Long-term benefits to the health of the population and a reduction in costs to the health system are expected to result. © 2016 British Association of Dermatologists.

  18. A tephra chronostratigraphic framework for the Frontier Mountain blue-ice field (northern Victoria Land, Antarctica)

    Science.gov (United States)

    Curzio, Pietro; Folco, Luigi; Ada Laurenzi, Marinella; Mellini, Marcello; Zeoli, Antonio

    2008-03-01

    Englacial tephra provide chronostratigraphic markers in the Antarctic ice sheets. Structural, mineralogical, geochemical and geochronological data on selected samples allowed the reconstruction of a chronostratigraphic framework for the Frontier Mountain blue-ice field—an important meteorite trap on the southeastern flank of Talos Dome in northern Victoria Land. The stratigraphic thickness of the blue-ice succession is ˜1150 m. The 40Ar- 39Ar age of one layer close to the stratigraphic bottom of the ice succession is 100±5 ka and constrains the maximum age of the bulk of Frontier Mountain blue ice. The 49±11 ka age of a second layer at a depth of ˜950 m in the stratigraphic succession indicates that >90% of the ice is younger than this value. These ages agree well with the terrestrial ages of meteorites found on the blue ice (up to 140±30 ka), suggesting a mechanism of exhumation of meteorites by ablation after englacial transport. Particle size (up to several tens of microns) and the alkaline compositional character of 22 layers allow correlation with source volcanoes within the Cenozoic magmatism associated with the West Antarctic Rift System. The proximal Mount Melbourne, Mount Rittman and The Pleiades (within a radius of ˜250 km) are the best candidate source volcanoes. The reconstructed chronostratigraphic framework thus lays the foundations for a detailed investigation of ˜100 ka of explosive volcanism in northern Victoria Land. Furthermore, in light of the ongoing ice core drilling project at Talos Dome, the Frontier Mountain ice succession may become important for establishing regional correlations, for sampling and dating key tephra layers, and for selecting ice successions for high-resolution studies of past atmospheric chemistry and fallout.

  19. Tradução para o Português de Queen Victoria in Her Letters and Journals de Christopher Hibbert

    OpenAIRE

    Monteiro, Caroline Feital

    2014-01-01

    A presente dissertação de mestrado tem como um dos objetivos produzir a tradução para o português de quatro seções da obra Queen Victoria in her letters and journals/ A Rainha Victoria em suas cartas e diários de Christopher Hibbert, publicada pela editora Sutton Publishing Limited na Inglaterra em 2000. Nas seções Queen regnant, Family life, Monarchs and ministers e ‘Frequent difficulties’, as anotações e as cartas da Rainha Victoria (1819-1901) da Inglaterra apresentam um pouco de história ...

  20. Comparing women pharmacy consumers’ experiences with weight loss treatment in Victoria and Nottingham: a cross-sectional study

    Science.gov (United States)

    2014-01-01

    Background There has been a recent increase in weight management services available in pharmacies across Australia and England. The aim of this study was to determine the following between women in Victoria and Nottingham: similarities and differences of what weight management options are preferred by women pharmacy consumers; how they feel about pharmacists providing advice in this area; and what they desire in a weight management program. Method Women pharmacy consumers were randomly approached by a researcher in community pharmacies in Victoria and Nottingham and asked to complete a questionnaire regarding their own weight management experiences. The questionnaire was self-completed or researcher-administered and was comprised of four main sections that focused on the participant’s general health, previous weight loss experiences, their ideal weight management program and their demographics. Data was entered in SPSS 19 and logistic regression was used to identify any differences in weight loss experiences between women. Results The participant rates were high: 86% (n = 395/460) in Victoria and 98% in Nottingham (n = 215/220). Overall, women in Victoria and Nottingham were similar with comparable demographics. Approximately 50% (250/507) of women were in the overweight or obese body mass index category, with over 70% (n = 436/610) of women having attempted to lose weight in the past. The majority of women (n = 334/436) felt comfortable receiving advice from pharmacists. In the logistic regression analysis women in Nottingham were found to be significantly less likely to have utilised a pharmacy weight management program in the last five years (OR: 0.23 CI: 0.08, 0.63) and were significantly less likely to want an ideal weight management program located in a pharmacy (OR: 0.49 CI: 0.30, 0.82) compared to women in Victoria. No significant associations between location and feeling comfortable with a pharmacist advising on weight loss or wanting a pharmacist in an

  1. Amphibians and squamate reptiles from the latest early Pleistocene of Cueva Victoria (Murcia, southeastern Spain, SW Mediterranean): Paleobiogeographic and paleoclimatic implications

    OpenAIRE

    BLAIN, H.A.; BAILON, S.; AGUSTÍ BALLESTER, J.

    2009-01-01

    The karstic filling of Cueva Victoria in southeastern Spain, dated from the latest early Pleistocene (ca. 1.1 Ma), is famous for providing primate fossil remains (Theropithecus) of typical African origin, in the general controversy on the antiquity of the first hominid settlements in Western Europe and their possible entrance into Europe through the Strait of Gibraltar. Cueva Victoria has also furnished the following fauna of anurans and squamate reptiles: cf. Pelodytes sp. (Pelodytidae), ...

  2. Scenario-based water resources planning for utilities in the Lake Victoria region

    Science.gov (United States)

    Mehta, V. K.; Aslam, O.; Dale, L.; Miller, N.; Purkey, D.

    2010-12-01

    Cities in the Lake Victoria (LV) region are experiencing the highest growth rates in Africa, at the same time that their water resource is threatened by domestic waste and industrial pollution. Urban centers use local springs, wetlands and Lake Victoria as source waters. As efforts to meet increasing demand accelerate, integrated water resources management (IWRM) tools provide opportunities for utilities and other stakeholders to develop a planning framework comprehensive enough to include short term (e.g. landuse change), as well as longer term (e.g. climate change) scenarios. This paper presents IWRM models built using the Water Evaluation And Planning (WEAP) decision support system, for three pilot towns in the LV region - Bukoba (Tanzania), Masaka (Uganda), and Kisii (Kenya). Their current populations are 100,000, 70,000 and 200,000 respectively. Demand coverage is ~70% in Masaka and Bukoba, and less than 50% in Kisii. IWRM models for each town were calibrated under current system performance based on site visits, utility reporting and interviews. Projected water supply, demand, revenues and costs were then evaluated against a combination of climate, demographic and infrastructure scenarios upto 2050. In Masaka, flow and climate data were available to calibrate a runoff model to simulate streamflow at water intake. In Masaka, without considering climate change, the system is infrastructure-limited and not water availability (hydrology) limited until 2035, under projected population growth of 2.17%. Under a wet climate scenario as projected by GCM’s for the LV region, the current wetland source could supply all expected demands until 2050. Even under a drought scenario, the wetland could supply all demand until 2032, if the supply infrastructure is updated at an estimated cost of USD 10.8 million. However, demand targets can only be met at the expense of almost no water returning to the wetland downstream of the intake by 2035, unless substantial investments

  3. Rock Glaciers in the Upper Basin of Bermejo River, Santa Victoria, Argentina

    Science.gov (United States)

    Ahumada, A. L.; Íbáñez Palacios, G. P.; Toledo, M. A.; Páez, S. V.

    2013-05-01

    The Bermejo River is an international basin in the Tropical Andes, Santa Victoria range. The Santa Victoria range extend in N-S sense (22°08' and 23°00' South latitude between 65° and 65°30' West longitude). It maxim height is about 5.055 m s.n.m. and it average height is 3000 m s.n.m. There have been localize intact rock glaciers (active and inactive) and relict. The rock glaciers are frozen water reservoir and regulate the water regime in the high mountain over the world. The global warming effects have been express in this region with average annual air temperatures in increase: The series of temperatures of La Quiaca weather station, years 1911-2010, shows an increase about 1° C (from 9,14° C to 10,08° C) since 70' decade to actuality. This study aims to contribute to the survey of intact rock glaciers and the suite of accompanying landforms. The geographic identification and location of rock glaciers have made through the interpretation of aerial photographs and LandSat 7 and Aster Images in comparison with Google Earth using GIS and visual interpretation technics. This information has controlled with fieldwork in several campaigns. The rock glaciers are classified (in base of it activity) in actives, inactives and relict. The first and the second class were grouped in a category called intact rock glaciers for simplify it identification. The unified categories are water-storing. In the fieldwork have determinated the following aspects: 1- Active processes determination (needle ice, lenticular ice formation, etc.) and its sedimentary products: sucrose structure, inverted gradation, extrusion, open work gravels. 2- Location and geomorphologic measurement of rock glaciers and periglacial forms. There are identified 318 intact rock glaciers in high basin of Bermejo river, Sub-basins Condado river, Los Toldos-Lipeo river and Iruya river, Santa Victoria range. The actives rock glaciers, indicators of discontinuous permafrost, are installed from 4300 m s

  4. Religión y religiosidad en la poesía de María Victoria Atencia

    OpenAIRE

    Gómez Yebra, Antonio Agustín

    2015-01-01

    La poesía de María Victoria Atencia está hecha de fervores y de claridades, dijo Manuel Alcántara cuando la presentó como pregonera de la Semana Santa de Málaga en 1985. El contacto con Dios, oral (y sentimental), es una de las señales de la piedad de María Victoria, que cree en el Dios de la religión católica, tan fuertemente marcada por la herencia hebrea del Antiguo Testamento, pero que ella ha heredado fundamentalmente a través del Nuevo. De los primeros libros de la Biblia hay a...

  5. Outbreaks of sarcoptic mange in free-ranging koala populations in Victoria and South Australia: a case series.

    Science.gov (United States)

    Speight, K N; Whiteley, P L; Woolford, L; Duignan, P J; Bacci, B; Lathe, S; Boardman, W; Scheelings, T F; Funnell, O; Underwood, G; Stevenson, M A

    2017-07-01

    To describe outbreaks of sarcoptic mange caused by Sarcoptes scabiei in free-ranging koalas in Victoria (December 2008 to November 2015) and South Australia (October 2011 to September 2014). Koalas affected by mange-like lesions were reported by wildlife carers, veterinary practitioners or State Government personnel to the Faculty of Veterinary and Agricultural Sciences at The University of Melbourne and the School of Animal and Veterinary Sciences at The University of Adelaide. Skin scrapings were taken from live and dead koalas and S. scabiei mites were identified. Tissues from necropsied koalas were examined histologically. Outbreaks of sarcoptic mange were found to occur in koalas from both Victoria (n = 29) and South Australia (n = 29) for the first time. The gross pathological and histopathological changes are described. We present the first reported cases of sarcoptic mange outbreaks in free-ranging koalas. © 2017 Australian Veterinary Association.

  6. Characterization of Staphylococcus aureus isolates from raw milk sources in Victoria, Australia.

    Science.gov (United States)

    McMillan, Kate; Moore, Sean C; McAuley, Catherine M; Fegan, Narelle; Fox, Edward M

    2016-07-29

    Highly pathogenic strains of Staphylococcus aureus can cause disease in both humans and animals. In animal species, including ruminants, S. aureus may cause severe or sub-clinical mastitis. Dairy animals with mastitis frequently shed S. aureus into the milk supply which can lead to food poisoning in humans. The aim of this study was to use genotypic and immunological methods to characterize S. aureus isolates from milk-related samples collected from 7 dairy farms across Victoria. A total of 30 S. aureus isolates were collected from milk and milk filter samples from 3 bovine, 3 caprine and 1 ovine dairy farms across Victoria, Australia. Pulsed Field Gel Electrophoresis (PFGE) identified 11 distinct pulsotypes among isolates; all caprine and ovine isolates shared greater than 80 % similarity regardless of source. Conversely, bovine isolates showed higher diversity. Multi-Locus Sequence Typing (MLST) identified 5 different sequence types (STs) among bovine isolates, associated with human or ruminant lineages. All caprine and ovine isolates were ST133, or a single allele variant of ST133. Two new novel STs were identified among isolates in this study (ST3183 and ST3184). With the exception of these 2 new STs, eBURST analysis predicted all other STs to be founding members of their associated clonal complexes (CCs). Analysis of genetic markers revealed a diverse range of classical staphylococcal enterotoxins (SE) among isolates, with 11 different SEs identified among bovine isolates, compared with just 2 among caprine and ovine isolates. None of the isolates contained mecA, or were resistant to oxacillin. The only antibiotic resistance identified was that of a single isolate resistant to penicillin; this isolate also contained the penicillin resistance gene blaZ. Production of SE was observed at 16 °C and/or 37 °C in milk, however no SE production was detected at 12 °C. Although this study characterized a limited number of isolates, bovine-associated isolates

  7. A high-resolution aeromagnetic survey over the Lanterman Range, northern Victoria Land, Antarctica

    Science.gov (United States)

    Ruppel, Antonia; Läufer, Andreas; Crispini, Laura; Capponi, Giovanni; Lisker, Frank

    2017-04-01

    During the GANOVEX XI (German North Victoria Land Expedition) in 2015-16, a high-resolution aeromagnetic survey was carried out over the Lanterman Range in northern Victoria Land (NVL). The helicopter-based survey aimed to resolve the fine structure over the so-called Lanterman Suture Zone, which represents one of the main key areas regarding geodynamic evolution of NVL during the Early Palaeozoic Ross Orogeny. This was achieved by reducing the flight line spacing to 1-2 km with 10 km tie lines and flying in a terrain-following mode. The survey was completed by ground truth magnetic susceptibility readings by using a Kappameter KM-7. The Ross-aged basement of NVL is subdivided into three tectonometamorphic so-called "terranes", comprising from W to E the Wilson-, the Bowers- and the Robertson Bay Terrane. They are generally interpreted to have formed by accretion processes at the Palaeo-Pacific active continental margin of East Gondwana in the Cambrian and Ordovician. The survey over the Lanterman Range covered parts of the two western terranes, namely the Wilson and Bowers terranes, which are separated by the Lanterman Fault Zone. This polyphase tectonic discontinuity is characterized by a belt of mafic and ultramafic rocks comprising metabasites with eclogite-facies relicts. Preliminary results show two distinct and nearly parallel magnetic lineaments in the survey area that will be further interpreted by combined magnetic susceptibility measurements and geological field data. One magnetic lineament correlates well with the known boundary between the Wilson and Bowers terranes, which comprises also a metaconglomerate belt with mafic to ultramafic clasts. The second, further easterly magnetic lineament is so far not supported by outcrops of associated highly magnetic rocks in the field. Similar parallel structures have been observed further to the southeast and seem to be offset by a major sinistral strike-slip fault zone of possibly post-Jurassic age. One

  8. Approach to medical missions: Dr. Neil Macvicar and the Victoria Hospital, Lovedale, South Africa, circa 1900-1950

    OpenAIRE

    Lunde, Martin Jacob

    2009-01-01

    This thesis examines the thought, work, and impact of the Scottish medical missionary, Dr Neil Macvicar, as well other personnel connected to the Victoria Hospital at the Lovedale mission in the Eastern Cape. Of special concern for study in medical history, missiology, and relief development studies, this work centres on Macvicar’s modern Western conceptions of Christianity, biomedicine, civilisation, African cosmological understandings, and traditional methods of healing, within the last ye...

  9. An overview of Australia?s Phytophthora species assemblage in natural ecosystems recovered from a survey in Victoria

    OpenAIRE

    Dunstan, William A.; Howard, Kay; StJ. Hardy, Giles E.; Burgess, Treena I.

    2016-01-01

    Although Phytophthora species cause serious diseases worldwide, until recently the main focus on disease in natural ecosystems in southern Australia has been on the distribution and impact of P. cinnamomi. However, new Phytophthora pathogens have emerged from natural ecosystems, and there is a need to better understand the diversity and distribution of these species in our natural forests, woodlands and heathlands. From a survey along a 70 km pipeline easement in Victoria, Phytophthora specie...

  10. Regions With Low Rates of Bystander Cardiopulmonary Resuscitation (CPR) Have Lower Rates of CPR Training in Victoria, Australia

    OpenAIRE

    Bray, Janet E.; Straney, Lahn; Smith, Karen; Cartledge, Susie; Case, Rosalind; Bernard, Stephen; Finn, Judith

    2017-01-01

    Background Bystander cardiopulmonary resuscitation (CPR) more than doubles the chance of surviving an out‐of‐hospital cardiac arrest. Recent data have shown considerable regional variation in bystander CPR rates across the Australian state of Victoria. This study aims to determine whether there is associated regional variation in rates of CPR training and willingness to perform CPR in these communities. Methods and Results We categorized each Victorian postcode as either a low or high bystand...

  11. Las guerras de las mujeres en la guerra :[homenaje a la teórica deminista Victoria Sau

    Directory of Open Access Journals (Sweden)

    Lourdes Pérez González

    2011-12-01

    This paper pays tribute to the work of the feminist theorist Victoria Sau. The article relies on the three mythological or literary figures used by the author to exemplify the different stages of feminism -Cassandra, Antigone and Lysistrata- in order to review the roles played in different moments and places by women in war, understood as a defence mechanism intended to preserve the patriarchal system. As long as this mechanism is not dismantled, these roles will not disappear.

  12. Biologically relevant physical measurements in the ice-free valleys of southern Victoria Land: soil temperature profiles and ultraviolet radiation

    Science.gov (United States)

    Nienow, J. A.; Meyer, M. A.; Friedmann, E. I. (Principal Investigator)

    1986-01-01

    As part of the ongoing comprehensive study of the cryptoendolithic microbial community in the ice-free valleys of southern Victoria Land, thermal properties of the soil and the ultraviolet radiation regime were measured. Although soil temperature profiles have been measured in the ice-free valleys (e.g., Cameron et al. 1970; Cameron 1972), these are the first such data from higher elevations. This is apparently the first time the ultraviolet radiation regime has been measured in the Antarctic.

  13. A study of heavy metal pollution in Lake Victoria sediments by Energy Dispersive X-Ray Fluorescence.

    Science.gov (United States)

    Makundi, I N

    2001-01-01

    Sources of heavy metal pollution of Lake Victoria is of interest due to its economic and domestic implication in East Africa. Sediments from the shore of Lake Victoria and from some streams flowing into the lake have been analyzed for their heavy metal content using Energy Dispersive X-Ray Fluorescence (EDXRF) analysis. The samples were collected from seventeen different locations around the Municipality of Mwanza divided into three zones according to their activities. The results show that sediments from Mwanza North, which is least in anthropogenic activities, contains Cr and Co in addition to metals of terrestrial origin (K, Ca, Ti, Mn, Fe, Rb, Sr, Y, and Zr), samples from Mwanza Central, which is the town center, contains high concentrations of V, Cu, Zn and Pb, and samples collected from Mwanza South, which is the industrial area, contains the highest concentrations of V, Cu, Zn, As and Pb. It is concluded that the industrial and sewage wastes discharged into the lake are the main sources of the heavy metal contamination of Lake Victoria. Further studies will be required to assess detriments of these pollutants to human and aquatic life before policy for the factories responsible is put in place.

  14. Climatic, socio-economic, and health factors affecting human vulnerability to cholera in the Lake Victoria basin, East Africa.

    Science.gov (United States)

    Olago, Daniel; Marshall, Michael; Wandiga, Shem O; Opondo, Maggie; Yanda, Pius Z; Kanalawe, Richard; Githeko, Andrew K; Downs, Tim; Opere, Alfred; Kavumvuli, Robert; Kirumira, Edward; Ogallo, Laban; Mugambi, Paul; Apindi, Eugene; Githui, Faith; Kathuri, James; Olaka, Lydia; Sigalla, Rehema; Nanyunja, Robinah; Baguma, Timothy; Achola, Pius

    2007-06-01

    Cholera epidemics have a recorded history in the eastern Africa region dating to 1836. Cholera is now endemic in the Lake Victoria basin, a region with one of the poorest and fastest growing populations in the world. Analyses of precipitation, temperatures, and hydrological characteristics of selected stations in the Lake Victoria basin show that cholera epidemics are closely associated with El Niño years. Similarly, sustained temperatures high above normal (T(max)) in two consecutive seasons, followed by a slight cooling in the second season, trigger an outbreak of a cholera epidemic. The health and socioeconomic systems that the lake basin communities rely upon are not robust enough to cope with cholera outbreaks, thus rendering them vulnerable to the impact of climate variability and change. Collectively, this report argues that communities living around the Lake Victoria basin are vulnerable to climate-induced cholera that is aggravated by the low socioeconomic status and lack of an adequate health care system. In assessing the communities' adaptive capacity, the report concludes that persistent levels of poverty have made these communities vulnerable to cholera epidemics.

  15. Potential Impacts of Climate Change on Precipitation over Lake Victoria, East Africa, in the 21st Century

    Directory of Open Access Journals (Sweden)

    Mary Akurut

    2014-08-01

    Full Text Available Precipitation over Lake Victoria in East Africa greatly influences its water balance. Over 30 million people rely on Lake Victoria for food, potable water, hydropower and transport. Projecting precipitation changes over the lake is vital in dealing with climate change impacts. The past and future precipitation over the lake were assessed using 42 model runs obtained from 26 General Circulation Models (GCMs of the newest generation in the Coupled Model Intercomparison Project (CMIP5. Two CMIP5 scenarios defined by Representative Concentration Pathways (RCP, namely RCP4.5 and RCP8.5, were used to explore climate change impacts. The daily precipitation over Lake Victoria for the period 1962–2002 was compared with future projections for the 2040s and 2075s. The ability of GCMs to project daily, monthly and annual precipitation over the lake was evaluated based on the mean error, root mean square error and the frequency of occurrence of extreme precipitation. Higher resolution models (grid size <1.5° simulated monthly variations better than low resolution models (grid size >2.5°. The total annual precipitation is expected to increase by less than 10% for the RCP4.5 scenario and less than 20% for the RCP8.5 scenario over the 21st century, despite the higher (up to 40% increase in extreme daily intensities.

  16. Control of swimming in the hydrozoan jellyfish Aequorea victoria: subumbrellar organization and local inhibition.

    Science.gov (United States)

    Satterlie, Richard A

    2008-11-01

    The subumbrella of the hydrozoan jellyfish Aequorea victoria (previously classified as Aequorea aequorea) is divided by numerous radial canals and attached gonads, so the subumbrellar musculature is partitioned into subumbrellar segments. The ectoderm of each segment includes two types of muscle: smooth muscle with a radial orientation, used for local (feeding and righting) and widespread (protective) radial responses, and striated muscle with a circular orientation which produces swim contractions. Two subumbrellar nerve nets were found, one of which stained with a commercial antibody produced against the bioactive peptide FMRFamide. Circular muscle cells produce a single, long-duration action potential with each swim, triggered by a single junctional potential. In addition, the circular cells are electrically coupled so full contractions require both electrotonic depolarization from adjacent cells and synaptic input from a subumbrellar nerve net. The radial cells, which form a layer superficial to the circular cells, are also activated by a subumbrellar nerve net, and produce short-duration action potentials. The radial muscle cells are electrically coupled to one another. No coupling exists between the two muscle layers. Spread of excitation between adjacent segments is decremental, and nerve net-activated junctional potentials disappear during local inhibition of swimming (such as with a radial response). Variable swim contractions are controlled by a combination of synaptic input from the motor network of the inner nerve ring, synaptic input from a subumbrellar nerve net, and electrotonic depolarization from adjacent, active muscle cells.

  17. A new marine ecosystem model for the University of Victoria Earth System Climate Model

    Directory of Open Access Journals (Sweden)

    D. P. Keller

    2012-09-01

    Full Text Available Earth System Climate Models (ESCMs are valuable tools that can be used to gain a better understanding of the climate system, global biogeochemical cycles and how anthropogenically-driven changes may affect them. Here we describe improvements made to the marine biogeochemical ecosystem component of the University of Victoria's ESCM (version 2.9. Major changes include corrections to the code and equations describing phytoplankton light limitation and zooplankton grazing, the implementation of a more realistic zooplankton growth and grazing model, and the implementation of an iron limitation scheme to constrain phytoplankton growth. The new model is evaluated after a 10 000-yr spin-up and compared to both the previous version and observations. For the majority of biogeochemical tracers and ecosystem processes the new model shows significant improvements when compared to the previous version and evaluated against observations. Many of the improvements are due to better simulation of seasonal changes in higher latitude ecosystems and the effect that this has on ocean biogeochemistry. This improved model is intended to provide a basic new ESCM model component, which can be used as is or expanded upon (i.e., the addition of new tracers, for climate change and biogeochemical cycling research.

  18. The impact of extensive loss of telecommunications on general practice: A case study in rural Victoria.

    Science.gov (United States)

    Tran, Nancy H; Pedler, Daryl

    2017-04-01

    To describe the impact of major loss of telecommunications on general practice in a rural region of Australia. A multi-stage qualitative study. Purposively selected participants were invited to contribute to initial data collection using an online survey, followed by interviews with selected participants. Thematic analysis of the data was performed by both research team members. South-western Victoria, Australia. Individuals from organisations involved in Telstra recovery efforts, disaster management, health care and general practice staff. The survey collected freeform responses from participants. Semi-structured interviews further explored a variety of experiences from purposively selected participants. Organisations and practices in the region were prepared for major disasters, but not for the unusual and 'limited' disaster of losing telecommunications, including lack of Internet access and loss of telephone services. Although alternative measures were found for telecommunications, there was still a significant impact on many health-care-related activities and general practice functionality during the outage period. In particular, there was an increase in duties for administrative staff to compensate for loss of telecommunications. Patient traffic for many services decreased due to uncertainty about availability and continuation of business. The Warrnambool outage could be used as a case study illustrating the dramatic impact of communication loss. Major impacts include changes in patient traffic, increased administrative duties and slowing of patient care. When developing or assessing disaster management plans, general practices should consider the impact of telecommunication loss on functionality and prepare appropriate alternative, accessible and reliable measures. © 2016 National Rural Health Alliance Inc.

  19. An overview of Australia's Phytophthora species assemblage in natural ecosystems recovered from a survey in Victoria.

    Science.gov (United States)

    Dunstan, William A; Howard, Kay; StJ Hardy, Giles E; Burgess, Treena I

    2016-06-01

    Although Phytophthora species cause serious diseases worldwide, until recently the main focus on disease in natural ecosystems in southern Australia has been on the distribution and impact of P. cinnamomi. However, new Phytophthora pathogens have emerged from natural ecosystems, and there is a need to better understand the diversity and distribution of these species in our natural forests, woodlands and heathlands. From a survey along a 70 km pipeline easement in Victoria, Phytophthora species were isolated from 249 rhizosphere samples and 25 bait bags deployed in 21 stream, river, or wetland locations. Of the 186 Phytophthora isolates recovered, 130 were identified to species based on ITS sequence data. Ninety-five isolates corresponded to 13 described Phytophthora species while additionally 35 isolates were identified as Clade 6 hybrids. Phytophthora cinnamomi was the most common species isolated (31 %), followed by P. elongata (6 %), both species were only recovered from soil. Samples from sites with the highest soil moisture at the time of sampling had the highest yield of isolates. Consistent with other studies throughout the world, Clade 6 species and their hybrids dominated water samples, although many of these species were also recovered less frequently from soil samples. Many of the species recovered in this study have not previously been reported from eastern Australia, reinforcing that Phytophthora species are widespread, abundant and diverse in natural ecosystems. We have probably been underestimating Phytophthora diversity in Australia.

  20. Reforming Defences to Homicide in Victoria: Another Attempt to Address the Gender Question

    Directory of Open Access Journals (Sweden)

    Bronwyn Naylor

    2017-08-01

    Full Text Available In 2005 in the Australian state of Victoria, significant changes were made to the defences to homicide. These reforms were in response to long standing concerns about the gendered operation of provocation and self-defence by feminist researchers and advocates, Law Reform Commissions, the media and political pressures. This paper critically examines the reforms and the extent to which they have addressed these varied concerns and interests. The paper argues that these important law reforms have challenged some of the powerful narratives being used in the courts that minimise the existence and significance of family violence in intimate relationships. We see this particularly in judicial sentencing remarks. However, law reform must be accompanied by a shift in legal culture to be effective in practice. To this end, we argue that legal professionals need to have information about how to utilise the new family violence provisions as well as ongoing training and professional development to promote consistent understandings of family violence across the criminal justice system.

  1. Psychiatric/Mental health nursing education in Victoria, Australia: barriers to specialization.

    Science.gov (United States)

    Happell, Brenda

    2006-04-01

    The introduction of undergraduate comprehensive nursing education in Victoria, Australia, during the 1990s has resulted in significant changes in undergraduate preparation for psychiatric/mental health nursing. Comprehensive programs became charged with the responsibility of preparing graduates to provide care for people experiencing a mental illness across a broad range of health-care settings, as well as providing a pathway for graduates with an interest in specialist practice in this field. The aim of this article is to clearly articulate the issues associated with psychiatric/mental health nursing education at the undergraduate level, including prevalence of mental illness, the inadequacy of psychiatric/mental health nursing theory and practice at undergraduate level, the negative attitudes of students toward this field of practice, and the subsequent failure of nursing education and practice initiatives to provide a clear mechanism for specialization in this important area of nursing practice. Throughout the article, the distinction between generalist and specialist preparation is argued and accompanied by a call for nursing education to recognize and address the issues associated with both domains.

  2. Development and reliability testing of the Victoria Bowel Performance Scale (BPS).

    Science.gov (United States)

    Downing, G Michael; Kuziemsky, Craig; Lesperance, Mary; Lau, Francis; Syme, Ann

    2007-11-01

    With changes in bowel function being a common and often distressful issue for palliative care patients, the ability to easily monitor and record changes in bowel status would be helpful in addressing quality of care. Most bowel tools record either constipation or diarrhea, but not both. A new tool, the Victoria Bowel Performance Scale (BPS), was designed as an ordinal nine-point scale from -4 (severe constipation) to +4 (severe diarrhea) and includes three parameters: visual stool characteristics, bowel pattern, and ability to control defecation. This study tested the reliability of BPS using case scenarios in a test-retest format. Sixty-seven raters in Time Period 1 and 54 raters in Time Period 2 ranked the 18 cases. The intraclass correlation coefficients for absolute agreement were 0.822 and 0.853 for Time Periods 1 and 2, respectively. Results showed that the raters were consistent in their scoring over time, with an average Cohen's kappa of 0.70 over all of the raters. The average Pearson correlation coefficient between Time Periods 1 and 2 scores was 0.92. Further prospective testing in day-to-day clinical care is needed to further confirm the reliability and clinical utility of the BPS. A BPS management guideline has been developed to assist with decision making for each BPS score, which also requires validation.

  3. Strategies used by dentists in Victoria, Australia, to manage children with anxiety or behavior problems.

    Science.gov (United States)

    Wright, F A; McMurray, N E; Giebartowski, J

    1991-01-01

    Two hundred and sixty-seven Australian dentists from the State of Victoria, representing members of the Australian Society of Dentistry for Children (AusSDC) and randomly selected practitioners, responded to a survey on attitudes and practices in the management of anxious children or children with behavior problems. The most common strategies used by dentists in this study were: permitting the child to exercise some form of control over terminating the treatment, if they were experiencing difficulties; furnishing waiting areas with play materials; and using a Tell-Show-Do approach to the provision of dental care. Members of the Australian Society of Dentistry for Children differed from general dentists by more frequently teaching anxious children a technique of relaxation and also by more frequently using a mouth prop or rubber dam during the delivery of care. Younger dentists tended to use behavioral strategies more frequently than older practitioners. Women dentists more frequently than male dentists, used strategies including: spending more time with the child before entering the operatory; setting shorter appointment sessions; and permitting the child to hold a toy or a mirror during dental treatment. In contrast to North American studies, few of the Australian dentists used the Hand-Over-Mouth technique to control hysteria. Australian dentists appeared to rely more frequently than their North American colleagues on setting shorter appointment sessions as a major strategy in managing children with anxiety or other behavioral difficulties.

  4. Motor vehicle exhaust gas suicide in Victoria, Australia 1998-2002.

    Science.gov (United States)

    Brennan, Chris; Routley, Virginia; Ozanne-Smith, Joan

    2006-01-01

    Motor vehicle exhaust gas suicide (MVEGS) is the second most frequent method of suicide in Victoria, Australia. It is a highly lethal method of suicide with 1.5 deaths for every hospital admission. Australian regulations require all vehicles manufactured since 1998 to have a maximum carbon monoxide exhaust emission level of 2.1 g/km, reduced from the previous level of 9.6 g/km. Information surrounding all Victorian MVEGS between 1998-2002 was analyzed to determine whether suicides occurred in vehicles with the lower emission levels. Between 1998-2002, 607 suicides by this means were recorded while just 393 hospital admissions were recorded for the same period. Mean carboxyhaemoglobin levels were significantly lower in fatalities using vehicles manufactured from 1998, however suicide still occurred in these vehicles (n = 25). The extent to which the new regulations contributed to the relatively low rate of suicide in vehicles less than 5 years old compared to their frequency in the fleet remains unknown. Based on international experience and the age of the Victorian vehicle fleet, it may take well over a decade until substantial decreases in MVEGS are observed in the absence of active preventive measures.

  5. Observed Marine Debris in the Pacific Ocean 00e2?? Victoria to Maui 2012

    Science.gov (United States)

    Location and descriptions of marine debris observed by the Sailing Vessel (S/V) Family Affair yacht during the Victoria, British Columbia to Maui, Hawaii Yacht Race in July 2012. These observations are organized according to the following map layers: Family Affairs Observations, Fleet Debris Levels, Return Vessels Special Reports, Roll Call Debris Data-Race, Special Report Debris-Race, Vessel Specific Observations, and Return Vessel Specific Levels Observations.The March, 2011 tsunami that affected northern Japan washed enormous amounts of debris out to sea. While most of this debris sank quickly out at sea, much remains on the surface and by ocean current and wind is working its way across the Pacific Ocean. In early days, the U.S. National Oceanic and Atmospheric Administration (NOAA) could track the debris slick by satellite, but by early 2012, the debris had become too dispersed to track. News stories have reported containers with motorcycles on Haida Gwaii, whole fishing boats in Alaska, and sections of concrete dock in Oregon. Recent reports are about the struggles of local governments to deal with cleaning up and disposing of flotsam washing up on local beaches.

  6. Unforeseen misuses of bed nets in fishing villages along Lake Victoria

    Directory of Open Access Journals (Sweden)

    Futami Kyoko

    2008-08-01

    Full Text Available Abstract Background To combat malaria, the Kenya Ministry of Health and nongovernmental organizations (NGOs have distributed insecticide-treated nets (ITNs for use over beds, with coverage for children under five years of age increasing rapidly. Nevertheless, residents of fishing villages have started to use these bed nets for drying fish and fishing in Lake Victoria. This study investigated the extent of bed net misuse in fishing villages. Methods Seven fishing villages along the lake were surveyed to estimate how widely bed nets were being used for fishing and drying fish. Villagers were asked why they used the bed nets for such purposes. Results In total, 283 bed nets were being used for drying fish. Of these, 239 were long-lasting insecticidal bed nets (LLIN and 44 were non-long-lasting insecticidal bed nets (NLLIN. Further, 72 of the 283 bed nets were also being used for fishing. The most popular reasons were because the bed nets were inexpensive or free and because fish dried faster on the nets. LLINs were preferred to NLLINs for fishing and drying fish. Conclusion There is considerable misuse of bed nets for drying fish and fishing. Many villagers are not yet fully convinced of the effectiveness of LLINs for malaria prevention. Such misuses may hamper the efforts of NGOs and governmental health organizations.

  7. Content analysis of school anti-bullying policies: a comparison between New Zealand and Victoria, Australia.

    Science.gov (United States)

    Marsh, Louise; McGee, Rob; Hemphill, Sheryl A; Williams, Sheila

    2011-12-01

    To undertake a detailed analysis of the content of anti-bullying policies in schools in New Zealand (NZ) and Victoria, Australia. The content of anti-bullying policies from 253 NZ schools and 93 Victorian schools were analysed in terms of definitions of bullying behaviour; reporting, recording and responding to bullying incidents; communicating and evaluating the policy; and outlining strategies for preventing bullying. There was a wide range in 'policy scores' between schools, and Victorian schools scored higher on nearly every area compared with NZ schools. In both regions, definitions rarely included bullying on the grounds of homophobia, religion or disability; or bullying between adults and students. Policies also lacked detail about the responsibilities of non-teaching staff in dealing with bullying, and rarely described follow-up after a bullying incident. Few policies explained how the policy would be evaluated, and many failed to mention preventive strategies. This study highlights some important areas that are deficient in NZ and Victorian school anti-bullying policies, and emphasises the need for guidance on how schools can develop an effective anti-bullying policy. Having more comprehensive anti-bullying policies will give schools a much better chance of reducing bullying.

  8. Highly Heterogeneous Soil Bacterial Communities around Terra Nova Bay of Northern Victoria Land, Antarctica

    Science.gov (United States)

    Lim, Hyoun Soo; Hong, Soon Gyu; Kim, Ji Hee; Lee, Joohan; Choi, Taejin; Ahn, Tae Seok; Kim, Ok-Sun

    2015-01-01

    Given the diminished role of biotic interactions in soils of continental Antarctica, abiotic factors are believed to play a dominant role in structuring of microbial communities. However, many ice-free regions remain unexplored, and it is unclear which environmental gradients are primarily responsible for the variations among bacterial communities. In this study, we investigated the soil bacterial community around Terra Nova Bay of Victoria Land by pyrosequencing and determined which environmental variables govern the bacterial community structure at the local scale. Six bacterial phyla, Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Cyanobacteria, and Bacteroidetes, were dominant, but their relative abundance varied greatly across locations. Bacterial community structures were affected little by spatial distance, but structured more strongly by site, which was in accordance with the soil physicochemical compositions. At both the phylum and species levels, bacterial community structure was explained primarily by pH and water content, while certain earth elements and trace metals also played important roles in shaping community variation. The higher heterogeneity of the bacterial community structure found at this site indicates how soil bacterial communities have adapted to different compositions of edaphic variables under extreme environmental conditions. Taken together, these findings greatly advance our understanding of the adaption of soil bacterial populations to this harsh environment. PMID:25799273

  9. Economic, social and resource management factors influencing groundwater trade: Evidence from Victoria, Australia

    Science.gov (United States)

    Gill, Bruce; Webb, John; Stott, Kerry; Cheng, Xiang; Wilkinson, Roger; Cossens, Brendan

    2017-07-01

    In Victoria, Australia, most groundwater resources are now fully allocated and opportunities for new groundwater development can only occur through trading of license entitlements. Groundwater usage has rarely exceeded 50% of the available licensed volume, even in the 2008/9 drought year, and 50 to 70% of individual license holders use less than 5% of their allocation each year. However, little groundwater trading is occurring at present. Interviews were conducted with groundwater license holders and water brokers to investigate why the Victorian groundwater trade market is underdeveloped. Responses show there is a complex mix of social, economic, institutional and technical reasons. Barriers to trade are influenced by the circumstances of each groundwater user, administrative process and resource management rules. Water brokers deal with few trades at low margins and noted unrealistic selling prices and administrative difficulties. Irrigators who have successfully traded identify that there are few participants in trading, technical appraisals are expensive and administrative requirements and fees are burdensome, especially when compared to surface water trading. Opportunities to facilitate trade include groundwater management plan refinement and improved information provision. Simplifying transaction processes and costs, demonstrating good resource stewardship and preventing third party impacts from trade could address some concerns raised by market participants. There are, however, numerous individual circumstances that inhibit groundwater trading, so it is unlikely that policy and process changes alone could increase usage rates without greater demand for groundwater or more favourable farming economic circumstances.

  10. Short-term droughts forecast using Markov chain model in Victoria, Australia

    Science.gov (United States)

    Rahmat, Siti Nazahiyah; Jayasuriya, Niranjali; Bhuiyan, Muhammed A.

    2017-07-01

    A comprehensive risk management strategy for dealing with drought should include both short-term and long-term planning. The objective of this paper is to present an early warning method to forecast drought using the Standardised Precipitation Index (SPI) and a non-homogeneous Markov chain model. A model such as this is useful for short-term planning. The developed method has been used to forecast droughts at a number of meteorological monitoring stations that have been regionalised into six (6) homogenous clusters with similar drought characteristics based on SPI. The non-homogeneous Markov chain model was used to estimate drought probabilities and drought predictions up to 3 months ahead. The drought severity classes defined using the SPI were computed at a 12-month time scale. The drought probabilities and the predictions were computed for six clusters that depict similar drought characteristics in Victoria, Australia. Overall, the drought severity class predicted was quite similar for all the clusters, with the non-drought class probabilities ranging from 49 to 57 %. For all clusters, the near normal class had a probability of occurrence varying from 27 to 38 %. For the more moderate and severe classes, the probabilities ranged from 2 to 13 % and 3 to 1 %, respectively. The developed model predicted drought situations 1 month ahead reasonably well. However, 2 and 3 months ahead predictions should be used with caution until the models are developed further.

  11. Liturgy and Music in Hereford Cathedral in the Time of Queen Victoria and Beyond

    Directory of Open Access Journals (Sweden)

    Tessa Murdoch

    2017-04-01

    Full Text Available The Victorian Gothic Revival and its focus on liturgical neo-medievalism inspired the 1860s restoration of the medieval Hereford Cathedral. In this restoration, the new screen played a central part. Designed by George Gilbert Scott and manufactured by the firm of Francis Skidmore in Coventry, the screen was commissioned in order to re-unite the choir with the nave. The symbolism and colours decorating the screen harmonized with the medieval and later features of the cathedral, including the high altar reredos, organ pipes, and floor tiles. Hereford Cathedral Library preserves historical accounts of the interior and original music manuscripts by Edward Elgar and Frederick Ouseley that illustrate, with the musical inserts provided, the rich tradition of choral music and liturgy which continues to this day with key liturgies and the annual Three Choirs Festival linking Gloucester, Hereford, and Worcester. Memorials and stained-glass windows dedicated to successive precentors embellish the musical vocabulary of the interior. In focusing on the musical culture connected with Hereford Cathedral, this essay seeks to enrich the interpretation of the restored Hereford Screen in its secular setting at the Victoria and Albert Museum, London.

  12. Is Gippsland environmentally iodine deficient? Water iodine concentrations in the Gippsland region of Victoria, Australia.

    Science.gov (United States)

    Rahman, Ashequr; Deacon, Nicholas; Panther, Barbara; Chesters, Janice; Savige, Gayle

    2010-12-01

      This paper provides evidence of environmental iodine deficiency in the Gippsland region.   Quantitative study; water samples were collected from 18 water treatment plants and four rain water tanks across Gippsland and water iodine concentrations were measured.   Gippsland region of Victoria, Australia.   This paper reports on the iodine concentration of drinking water from sources across Gippsland and examines the contribution of iodine from water to the Gippsland diet. This study also briefly examines the relationship between the concentration of iodine in water and distance from the sea. The cut-off value for water iodine concentrations considered to be indicative of environmental iodine deficiency is water from 18 Gippsland water treatment plants was 0.38 µg L(-1) and would therefore make negligible difference to the dietary intake of iodine. This finding also falls well below the suggested dietary intake of iodine from water estimated by the 22nd Australian Total Diet Study. Our study found no linear relationship between the water iodine concentration and distance from the sea.   As Gippsland has environmental iodine deficiency there is a greater probability that people living in this region are at higher risk of dietary iodine deficiency than those living in environmentally iodine sufficient regions. Populations living in areas known to have environmental iodine deficiency should be monitored regularly to ensure that problems of iodine deficiency, especially amongst the most vulnerable, are addressed promptly. © 2010 The Authors. Australian Journal of Rural Health © National Rural Health Alliance Inc.

  13. A study of autotrophic communities in two Victoria Land lakes (Continental Antarctica using photosynthetic pigments

    Directory of Open Access Journals (Sweden)

    Roberto BARGAGLI

    2010-08-01

    Full Text Available The composition of algal pigments and extracellular polymeric substances (EPS was determined in microbial mats from two lakes in Victoria Land (Continental Antarctica with different lithology and environmental features. The aim was to expand knowledge of benthic autotrophic communities in Antarctic lacustrine ecosystems, providing reference data for future assessment of possible changes in environmental conditions and freshwater communities. The results of chemical analyses were supported by microscopy observations. Pigment profiles showed that filamentous cyanobacteria are dominant in both lakes. Samples from the water body at Edmonson Point had greater biodiversity, fewer pigments and lower EPS ratios than those from the lake at Kar Plateau. Differences in mat composition and in pigment and EPS profile between the two lakes are discussed in terms of local environmental conditions such as lithology, ice-cover and UV radiation. The present study suggests that a chemical approach could be useful in the study of benthic communities in Antarctic lakes and their variations in space and time.

  14. Forensic odontology, part 3. The Australian bushfires - Victoria state, February 2009.

    Science.gov (United States)

    Hinchliffe, J

    2011-04-09

    This paper aims to demonstrate the stages in the disaster victim identification of those who lost their lives in the Australian bushfires that raged across the state of Victoria in February 2009. Communities were damaged or destroyed leaving families distressed and homeless, and as the number of deaths increased the Disaster Victim Identification (DVI) teams were activated, with plans evolving to deal with this emergency. The identification process was challenging due to many factors, such as the dangers and difficulties involved in body recovery and the charring and commingling of remains. It would take several months of careful work to identify the dead using a multidisciplinary approach. The impact of this incident will have long-lasting consequences for the families and communities involved. At the time of writing all but one of the 173 victims had been identified, mostly by dental methods: quite remarkable when only small fragments of the dental structures remained in many cases. This article is based on the author's personal experience working to assist the organised and experienced Australian Dental DVI Team.

  15. Public values for integration in natural disaster management and planning: A case study from Victoria, Australia.

    Science.gov (United States)

    Rawluk, Andrea; Ford, Rebecca M; Neolaka, Fendi L; Williams, Kathryn J

    2017-01-01

    Values can be useful for identifying what is important to individuals and communities, yet there is currently not a coherent way to conceptualize, identify, and organize the breadth of values that can be affected by a natural disaster. This research proposes a conceptual framework for how to conceptualize, identify, and organize values, and proposes a concrete, tangible value called the valued entity. The framework is applied in two studies of bushfire in Victoria, Australia: 112 submissions from individuals to the 2009 Victorian Bushfires Royal Commission and interviews with 30 members of the public in bushfire risk landscapes. Our findings suggest that: what people value ranges from abstract to concrete; prevalent abstract values include benevolence and universalism; prevalent mid-level valued attributes include natural attributes of landscapes and human life and welfare; prevalent valued entities are people and properties close to the person. Comparison between the two studies suggests people with more recent experience with bushfire refer less to the importance of natural places and natural attributes. The conceptual framework can act as a boundary object to facilitate researchers and policy-makers understanding the breadth of values affected by natural disaster events and management actions and how governance can better consider values at different scales. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Morchella australiana sp. nov., an apparent Australian endemic from New South Wales and Victoria.

    Science.gov (United States)

    Elliott, Todd F; Bougher, Neale L; O'Donnell, Kerry; Trappe, James M

    2014-01-01

    An abundant fruiting of a black morel was encountered in temperate northwestern New South Wales (NSW), Australia, during a mycological survey in Sep 2010. The site was west of the Great Dividing Range in a young, dry sclerophyll forest dominated by Eucalyptus and Callitris north of Coonabarabran in an area known as the Pilliga Scrub. Although the Pilliga Scrub is characterized by frequent and often large, intense wildfires, the site showed no sign of recent fire, which suggests this species is not a postfire morel. Caps of the Morchella elata-like morel were brown with blackish ridges supported by a pubescent stipe that became brown at maturity. Because no morel has been described as native to Australia, the collections were subjected to multilocus molecular phylogenetic and morphological analyses to assess its identity. Results of these analyses indicated that our collection, together with collections from NSW and Victoria, represented a novel, genealogically exclusive lineage, which is described and illustrated here as Morchella australiana T. F. Elliott, Bougher, O'Donnell & Trappe, sp. nov.

  17. Longitudinal effects of school drug policies on student marijuana use in Washington State and Victoria, Australia.

    Science.gov (United States)

    Evans-Whipp, Tracy J; Plenty, Stephanie M; Catalano, Richard F; Herrenkohl, Todd I; Toumbourou, John W

    2015-05-01

    We examined the longitudinal effect of schools' drug policies on student marijuana use. We used data from the International Youth Development Study, which surveyed state-representative samples of students from Victoria, Australia, and Washington State. In wave 1 (2002), students in grades 7 and 9 (n = 3264) and a school administrator from each participating school (n = 188) reported on school drug policies. In wave 2 (2003), students reported on their marijuana use. We assessed associations between student-reported and administrator-reported policy and student self-reported marijuana use 1 year later. Likelihood of student marijuana use was higher in schools in which administrators reported using out-of-school suspension and students reported low policy enforcement. Student marijuana use was less likely where students reported receiving abstinence messages at school and students violating school policy were counseled about the dangers of marijuana use. Schools may reduce student marijuana use by delivering abstinence messages, enforcing nonuse policies, and adopting a remedial approach to policy violations rather than use of suspensions.

  18. Microbiological Safety and Food Handling Practices of Seed Sprout Products in the Australian State of Victoria.

    Science.gov (United States)

    Symes, Sally; Goldsmith, Paul; Haines, Heather

    2015-07-01

    Seed sprouts have been implicated as vehicles for numerous foodborne outbreaks worldwide. Seed sprouts pose a unique food safety concern because of the ease of microbiological seed contamination, the inherent ability of the sprouting process to support microbial growth, and their consumption either raw or lightly cooked. To examine seed sprout safety in the Australian state of Victoria, a survey was conducted to detect specific microbes in seed sprout samples and to investigate food handling practices relating to seed sprouts. A total of 298 seed sprout samples were collected from across 33 local council areas. Escherichia coli was detected in 14.8%, Listeria spp. in 12.3%, and Listeria monocytogenes in 1.3% of samples analyzed. Salmonella spp. were not detected in any of the samples. A range of seed sprout handling practices were identified as potential food safety issues in some food businesses, including temperature control, washing practices, length of storage, and storage in proximity to unpackaged ready-to-eat potentially hazardous foods.

  19. Finding Space for Participation: Fisherfolk Mobility and Co-Management of Lake Victoria Fisheries

    Science.gov (United States)

    Nunan, Fiona; Luomba, Joseph; Lwenya, Caroline; Yongo, Ernest; Odongkara, Konstantine; Ntambi, Baker

    2012-08-01

    The literature on fisheries co-management is almost silent on the issue of the movement of fisherfolk within fisheries, although such movement must have implications for the effectiveness of co-management. The introduction of co-management often involves the formation of new structures that should enable the participation of key stakeholder groups in decision-making and management, but such participation is challenging for migrating fishers. The article reports on a study on Lake Victoria, East Africa, which investigated the extent of movement around the lake and the implications of movement for how fishers participate and are represented in co-management, and the implications of the extent and nature of movement for co-management structures and processes. The analysis draws on the concept of space from the literature on participation in development and on a framework of representation in fisheries co-management in addressing these questions. The created space is on an `invited' rather than open basis, reflecting the top-down nature of implementation and the desire to secure participation of different occupational groups, as well as women in a male-dominated sector. The more powerful boat owners dominate positions of power within the co-management system, particularly as the levels of co-management, from sub-district to national, are traversed. The limited power and resources of boat crew are exacerbated by the degree and nature of movement around the lake, making effective participation in co-management decision-making a challenge.

  20. A positive association between cryptosporidiosis notifications and ambient temperature, Victoria, Australia, 2001-2009.

    Science.gov (United States)

    Kent, Lillian; McPherson, Michelle; Higgins, Nasra

    2015-12-01

    Increased temperatures provide optimal conditions for pathogen survival, virulence and replication as well as increased opportunities for human-pathogen interaction. This paper examined the relationship between notifications of cryptosporidiosis and temperature in metropolitan and rural areas of Victoria, Australia between 2001 and 2009. A negative binomial regression model was used to analyse monthly average maximum and minimum temperatures, rainfall and the monthly count of cryptosporidiosis notifications. In the metropolitan area, a 1 °C increase in monthly average minimum temperature of the current month was associated with a 22% increase in cryptosporidiosis notifications (incident rate ratio (IRR) 1.22; 95% confidence interval (CI) 1.13-1.31). In the rural area, a 1 °C increase in monthly average minimum temperature, lagged by 3 months, was associated with a 9% decrease in cryptosporidiosis notifications (IRR 0.91; 95% CI 0.86-0.97). Rainfall was not associated with notifications in either area. These relationships should be considered when planning public health response to ecological risks as well as when developing policies involving climate change. Rising ambient temperature may be an early warning signal for intensifying prevention efforts, including appropriate education for pool users about cryptosporidiosis infection and management, which might become more important as temperatures are projected to increase as a result of climate change.

  1. Selection of electrogenic bacteria for microbial fuel cell in removing Victoria blue R from wastewater.

    Science.gov (United States)

    Chen, Chih-Yu; Tsai, Teh-Hua; Wu, Pei-Ssu; Tsao, Shuo-En; Huang, Yu-Shan; Chung, Ying-Chien

    2018-01-28

    This study was conducted to select electrogenic bacteria from wastewater sludge. Phylogenetic analysis revealed that Proteobacteria was the dominant phylum in the microbial fuel cell (MFC) during the decomposition process of organic pollutants. Five culturable bacteria strains - namely, Bacillus subtilis, Flavobacterium sp., Aeromonas hydrophila, Citrobacter freundii, and Stenotrophomonas sp. - have a double potential in dye removal and electricity generation. We inoculated the mixed electrogenic bacteria at a specific ratio and treated them with a triphenylmethane dye, Victoria blue R (VBR), to evaluate their electricity generation ability for the artificial and real wastewater. The results of the VBR shock-loading experiment indicated that the inoculated MFC could adapt to shock loading in 1-2 days and exhibited high removal efficiency (95-100%) for 100-800 mg L-1 VBR with a power density of 8.62 ± 0.10 to 34.81 ± 0.25 mW m-2. The selected electrogenic bacteria in the MFC could use VBR as only electron donor for power generation. The matrix effects of the real wastewater on VBR removal and electricity generation of MFC were insignificant. VBR degradation by the electrogenic bacteria involves a stepwise demethylation process to yield partially dealkylated VBR species. In addition, these results demonstrate the feasibility of inoculating culturable bacteria strains to develop an efficient MFC for purifying wastewater.

  2. The photodynamic effect of Victoria blue BO on peripheral blood mononuclear and leukemic cells

    Energy Technology Data Exchange (ETDEWEB)

    Fiedorowicz, M. [Hugo Kollatay Univ. of Agriculture, Krakow (Poland); Pituch-Noworolska, A.; Zembala, M. [Polish-American Children`s Hospital, Krakow (Poland). Dept. of Clinical Immunology

    1997-05-01

    The photodynamic effect of Victoria blue BO (VB-BO) and photoirradiation on peripheral blood mononuclear cells was studied. The cells were preincubated with VB-BO followed by photoirradiation and overnight culture. The highest percentage of dead cells (propidium iodide assay in flow cyctometry) was seen in the monocyte population. The lymphocytes showed a lower sensitivity to VB-BO photodynamic action than the monocytes (12% vs 80% of PI-positive cells). The effect of VB-BO and phototreatment on lymphocyte function was studied using a mitogen-induced proliferation assay. A decrease of mitogen response was observed. The VB-BO and photoirradiation were also used on leukemic cells. The leukemic cells from acute myeloid leukemia and B precursors leukemia were sensitive to VB-BO photodynamic action. The high VB-BO sensitivity of monocytes and leukemic cells (myeloid and lymphoid B derived) suggests possible application of VB-BO for selective depletion of monocytes or sensitive leukemic cells. (author).

  3. Sensitive voltammetric detection of yeast RNA based on its interaction with Victoria Blue B

    Directory of Open Access Journals (Sweden)

    WEI SUN

    2009-12-01

    Full Text Available Voltammetric studies of the interaction of yeast RNA (y-RNA with Victoria Blue B (VBB are described in this paper. Furthermore, a linear sweep voltammetric method for the detection of y-RNA was established. The reaction conditions, such as acidity and amount of buffer solution, the concentration of VBB, the reaction time and temperature, etc., were carefully investigated by second order derivative linear sweep voltammetry. Under the optimal conditions, the reduction peak current of VBB at –0.75 V decreased greatly after the addition of y-RNA to the solution without any shift of the reduction peak potential. Based on the decrease of the peak current, a new quantitative method for the determination of y-RNA was developed. The effects of co-existing substances on the determination were carefully investigated and three synthetic samples were determined with satisfactory results. The stoichiometry of the VBB–y-RNA complex was calculated by linear sweep voltammetry and the interaction mechanism is discussed.

  4. Relationships between body fatness, small-screen sedentary activity and regionality among schoolchildren in Victoria, Australia.

    Science.gov (United States)

    Aucote, Helen M; Cooper, Andrew

    2009-06-01

    To examine the difference in body fatness and engagement in small-screen activities across children living in different degrees of regionality, and to examine the relationship between child body fatness and small-screen activities. Cross-sectional study design. Grade 5-6 schoolchildren (n = 393) from central and metropolitan Victoria, and a parent/guardian of each child (n = 393). Parents completed a questionnaire on their child's engagement in television (TV) viewing and video game playing (VGP). Children's weight and height were measured by a researcher. Body mass index (BMI) (kg/m(2)) was calculated and adjusted for age and sex. Regionality (metropolitan, population > 100 000; regional, 100 000 > population < 20 000; and rural, population < 10 000) and socioeconomic status (socioeconomic indexes for areas: index of disadvantage) were assigned according to school attended. BMI did not differ across regionality or sex. Boys engaged in more VGP than girls, and metropolitan children engaged in more VGP than rural and regional children. TV viewing did not differ across sex or regionality. VGP did not predict BMI, and TV viewing did not predict girls' BMI. Three to four per cent of the variance in boys' BMI was predicted by TV viewing. Boys and metropolitan children engage in more VGP. Boys', but not girls', BMI is related to TV viewing. Interventions designed to decrease engagement in TV viewing should be targeting boys.

  5. The shortened dental arch concept: awareness and opinion of dentists in Victoria, Australia.

    Science.gov (United States)

    Abuzar, M A; Humplik, A J; Shahim, N

    2015-09-01

    The occlusion of a complete dental arch is generally desirable but not necessary nor always achievable in many individuals. It is, however, relevant for dentists to consider what minimum number of teeth is required by individuals for oral function. This study investigated dentists' awareness and opinion of the shortened dental arch (SDA) concept in an Australian context. A self-administered voluntary and anonymous questionnaire was mailed to a sample of 434 dentists, randomly selected from both rural and metropolitan locations in Victoria, Australia. The information collected included awareness of the SDA concept and its application as a treatment option. More than half of the respondents (61%) were aware of the SDA concept. All respondents 'agreed' or 'strongly agreed' with the seven criteria of SDA proposed in this study based on Käyser (1989). The majority (78.4%) believed that the SDA concept is useful in clinical practice. Dentists with dentists who responded to this survey agreed that the SDA is a practical and useful treatment modality for older adults with limitations to complex restorative care. However, application of the SDA varied considerably among dentists. © 2015 Australian Dental Association.

  6. Psychological distress and risky sexual behaviours among women aged 16-25 years in Victoria, Australia.

    Science.gov (United States)

    Nguyen, Nhuong T; Subasinghe, Asvini K; Wark, John D; Reavley, Nicola; Garland, Suzanne M

    2017-12-01

    Identifying factors related to risky sexual behaviour may contribute to preventive and interventional approaches to reduce negative mental health outcomes among young women. The aim of this study was to investigate the association between psychological distress and risky sexual behaviours in females aged 16-25 years in Victoria, Australia. Data were extracted from the Young Female Health Initiative (YFHI), a study in which participants were recruited via advertisements on Facebook. Logistic regression was used to assess associations between psychological distress, as measured by the Kessler 10 (K10) Psychological Distress Scale, and risky sexual behaviours. Data were available from 200 sexually active participants and 40 non-sexually active participants. We found that the K10 score was independently associated with sex while under the influence of alcohol or drugs (odds ratio: 1.7; 95% confidence intervals: 1.2, 2.7; P = 0.006). Although data were collected from a small sample of young women, we found that those with underlying psychological distress may adopt risky sexual behaviours, especially if concomitantly drinking alcohol or taking drugs.

  7. Socio-demographic profile of child and adolescent users of oral health services in Victoria, Australia

    Directory of Open Access Journals (Sweden)

    J Rodrigo

    2014-09-01

    Full Text Available The aim of this study was to investigate the socio-demographic characteristics of the eligible population of users of public oral health care services in the Australian state of Victoria, aged 17 years or younger. The study was conducted as a secondary analysis of data collected from July 2008 to June 2009 for 45,728 young clients of public oral health care. The sample mean age was 8.9 (SD: 3.5 years. The majority (82.7% was between 6 and 17 years of age, and 50.3% were males. The majority (76.6% was Australian-born and spoke English at home (89.1%. The overall mean DMFT was 1.0 (SD: 2.1 teeth, with a mean dmft of 3.16 (SD: 5.79 teeth. Data indicate that, among six year olds in the Significant Caries Index (SiC category, the mean dmft was 6.82 teeth. Findings corroborate social inequalities in oral health outcome and provide suggestions for oral health services to develop strategies and priorities to reduce inequalities in health and well-being, and better coordinate and target services to local needs.

  8. Continuous bioelectricity generation through treatment of Victoria blue R: A novel microbial fuel cell operation.

    Science.gov (United States)

    Chen, Chih-Yu; Wang, Guey-Horng; Tsai, Teh-Hua; Chen, Wan-Tzu; Chung, Ying-Chien

    2017-07-29

    A novel two-chamber microbial fuel cell (MFC) operation with a continuous anaerobic-aerobic decolorization system was developed to improve the degradation of the triphenylmethane dye, Victoria blue R (VBR). In addition, bioelectricity was generated during the VBR degradation process, and the operation parameters were optimized. The results indicated that the VBR removal efficiency and electricity generation were affected by the VBR concentration, liquid retention time (LRT), external resistance, gas retention time (GRT), and shock loading. The optimal operation parameters were as follows: VBR concentration, 600 mg L-1; LRT, 24 h; external resistance, 3300 Ω; and GRT, 60 s. Under these operating conditions, the VBR removal efficiency, COD removal efficiency, and power density were 98.2% ± 0.3%, 97.6% ± 0.5%, and 30.6 ± 0.4 mW m-2, respectively. According to our review of the relevant literature, this is the first paper to analyze the electrical characteristics of a continuous two-chamber MFC operation and demonstrate the feasibility of the simultaneous electricity generation and decolorization of VBR.

  9. Untangling the evolutionary history of a highly polymorphic species: introgressive hybridization and high genetic structure in the desert cichlid fish Herichtys minckleyi.

    Science.gov (United States)

    Magalhaes, Isabel S; Ornelas-Garcıa, Claudia Patricia; Leal-Cardin, Mariana; Ramírez, Tania; Barluenga, Marta

    2015-09-01

    Understanding the origin of biodiversity requires knowledge on the evolutionary processes that drive divergence and speciation, as well as on the processes constraining it. Intraspecific polymorphisms can provide insight into the mechanisms that generate and maintain phenotypic, behavioural and life history diversification, and can help us understand not only the processes that lead to speciation but also the processes that prevent local fixation of morphs. The 'desert cichlid' Herichtys minckleyi is a highly polymorphic species endemic to a biodiversity hotspot in northern Mexico, the Cuatro Ciénegas valley. This species is polymorphic in body shape and trophic apparatus, and eco-morphotypes coexist in small spring-fed lagoons across the valley. We investigated the genetic structure of these polymorphisms and their phylogeographic history by analysing the entire control region of the mitochondrial DNA and 10 nuclear microsatellite markers in several populations from different sites and morphs. We found two very divergent mitochondrial lineages that most likely predate the closing of the valley and are not associated with morphotypes or sites. One of these lineages is also found in the sister species Herichthys cyanoguttatus. Data from neutral microsatellite markers suggest that most lagoons or drainages constitute their own genetic cluster with sympatric eco-morphotypes forming panmictic populations. Alternative mechanisms such as phenotypic plasticity and a few loci controlled traits provide possible explanations for the sympatric coexistence of discrete nonoverlapping eco-morphotypes with apparent lack of barriers to gene flow within multiple lagoons and drainages. © 2015 John Wiley & Sons Ltd.

  10. Audience Effects in Territorial Defense of Male Cichlid Fish Are Associated with Differential Patterns of Activation of the Brain Social Decision-Making Network

    Science.gov (United States)

    Roleira, António; Oliveira, Gonçalo A.; Lopes, João S.; Oliveira, Rui F.

    2017-01-01

    Animals communicate by exchanging signals frequently in the proximity of other conspecifics that may detect and intercept signals not directed to them. There is evidence that the presence of these bystanders modulates the signaling behavior of interacting individuals, a phenomenon that has been named audience effect. Research on the audience effect has predominantly focused on its function rather than on its proximate mechanisms. Here, we have investigated the physiological and neuromolecular correlates of the audience effect in a cichlid fish (Mozambique tilapia, Oreochromis mossambicus). A male was exposed to a territorial intrusion in the presence or absence of a female audience. Results showed that the presence of the female audience increased territorial defense, but elicited a lower androgen and cortisol response to the territorial intrusion. Furthermore, analysis of the expression of immediate early genes, used as markers of neuronal activity, in brain areas belonging to the social decision-making network (SDMN) revealed different patterns of network activity and connectivity across the different social contexts (i.e., audience × intrusion). Overall, these results suggest that socially driven plasticity in the expression of territorial behavior is accommodated in the central nervous system by rapid changes in functional connectivity between nodes of relevant networks (SDMN) rather than by localized changes of activity in specific brain nuclei. PMID:28620286

  11. Redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado, 1978 (Acanthocephala: Neoechinorhynchidae) and description of a new species from freshwater cichlids (Teleostei: Cichlidae) in Mexico.

    Science.gov (United States)

    Salgado-Maldonado, Guillermo

    2013-05-01

    A redescription of Neoechinorhynchus (Neoechinorhynchus) golvani Salgado-Maldonado (An Inst Biol Univ Nal Autón Méx, Ser Zool 49:35-47, 1978) is presented, based on adult specimens collected from the type host Paraneetroplus fenestratus from the type location, the Lago de Catemaco lake, Veracruz state, Mexico, and its presence is recorded in other cichlids. Detailed studies of N. (N.) golvani using light microscopy revealed some taxonomically important, previously unreported features, such as the size and shape of fully developed adult males and females, and the structure of the eggs. Morphological variability in N. (N.) golvani is described. Based on these data, the geographic distribution of this species is documented. Neoechinorhynchus (Neoechinorhynchus) panucensis n. sp. is described from Herichthys labridens (Pellegrin), Amatitlania nigrofasciata (Günther), and Herichthys cyanoguttatus Baird and Girard (all of them Cichlidae), collected in the Río Atlapexco, a tributary to the upper Río Panuco basin, Hidalgo State, Mexico. This new species stand up alone because of its minute proboscis (♂ 50 × 60, ♀ 42-55 (48.5) × 48-63 (57.7)) and anterior hooks (♂ 27-30 (28.8) × 3-5 (4), ♀ 28-32 (30) × 5 (5)). A key to the species of Neoechinorhynchus recorded from freshwater fishes in Central and South America is included.

  12. Comparative support for the expensive tissue hypothesis: Big brains are correlated with smaller gut and greater parental investment in Lake Tanganyika cichlids.

    Science.gov (United States)

    Tsuboi, Masahito; Husby, Arild; Kotrschal, Alexander; Hayward, Alexander; Buechel, Séverine D; Zidar, Josefina; Løvlie, Hanne; Kolm, Niclas

    2015-01-01

    The brain is one of the most energetically expensive organs in the vertebrate body. Consequently, the energetic requirements of encephalization are suggested to impose considerable constraints on brain size evolution. Three main hypotheses concerning how energetic constraints might affect brain evolution predict covariation between brain investment and (1) investment into other costly tissues, (2) overall metabolic rate, and (3) reproductive investment. To date, these hypotheses have mainly been tested in homeothermic animals and the existing data are inconclusive. However, there are good reasons to believe that energetic limitations might play a role in large-scale patterns of brain size evolution also in ectothermic vertebrates. Here, we test these hypotheses in a group of ectothermic vertebrates, the Lake Tanganyika cichlid fishes. After controlling for the effect of shared ancestry and confounding ecological variables, we find a negative association between brain size and gut size. Furthermore, we find that the evolution of a larger brain is accompanied by increased reproductive investment into egg size and parental care. Our results indicate that the energetic costs of encephalization may be an important general factor involved in the evolution of brain size also in ectothermic vertebrates. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  13. Temporal variation of Mexiconema cichlasomae (Nematoda: Daniconematidae) in the Mayan cichlid fish Cichlasoma urophthalmus and its intermediate host Argulus yucatanus from a tropical coastal lagoon.

    Science.gov (United States)

    May-Tec, A L; Pech, D; Aguirre-Macedo, M L; Lewis, J W; Vidal-Martínez, V M

    2013-03-01

    The aim of the present investigation was to determine whether temporal variation in environmental factors such as rainfall or temperature influence long-term fluctuations in the prevalence and mean abundance of the nematode Mexiconema cichlasomae in the cichlid fish Cichlasoma uropthalmus and its crustacean intermediate host, Argulus yucatanus. The study was undertaken in a tropical coastal lagoon in the Yucatan Peninsula (south-eastern Mexico) over an 8-year period. Variations in temperature, rainfall and monthly infection levels for both hosts were analysed using time series and cross-correlations to detect possible recurrent patterns. Infections of M. cichlasomae in A. yucatanus showed annual peaks, while in C. urophthalmus peaks were bi-annual. The latter appear to be related to the accumulation of several generations of this nematode in C. urophthalmus. Rainfall and temperature appear to be key environmental factors in influencing temporal variation in the infection of M. cichlasomae over periods longer than a year together with the accumulation of larval stages throughout time.

  14. A sex-specific trade-off between mating preferences for genetic compatibility and body size in a cichlid fish with mutual mate choice.

    Science.gov (United States)

    Thünken, Timo; Meuthen, Denis; Bakker, Theo C M; Baldauf, Sebastian A

    2012-08-07

    Mating preferences for genetic compatibility strictly depend on the interplay of the genotypes of potential partners and are therein fundamentally different from directional preferences for ornamental secondary sexual traits. Thus, the most compatible partner is on average not the one with most pronounced ornaments and vice versa. Hence, mating preferences may often conflict. Here, we present a solution to this problem while investigating the interplay of mating preferences for relatedness (a compatibility criterion) and large body size (an ornamental or quality trait). In previous experiments, both sexes of Pelvicachromis taeniatus, a cichlid fish with mutual mate choice, showed preferences for kin and large partners when these criteria were tested separately. In the present study, test fish were given a conflicting choice between two potential mating partners differing in relatedness as well as in body size in such a way that preferences for both criteria could not simultaneously be satisfied. We show that a sex-specific trade-off occurs between mating preferences for body size and relatedness. For females, relatedness gained greater importance than body size, whereas the opposite was true for males. We discuss the potential role of the interplay between mating preferences for relatedness and body size for the evolution of inbreeding preference.

  15. GH, IGF-I and GH receptors mRNA expression in response to growth impairment following a food deprivation period in individually housed cichlid fish Cichlasoma dimerus.

    Science.gov (United States)

    Delgadin, Tomás Horacio; Pérez Sirkin, Daniela Irina; Di Yorio, María Paula; Arranz, Silvia Eda; Vissio, Paula Gabriela

    2015-02-01

    Cichlasoma dimerus is a social cichlid fish capable of growing at high rates under laboratory conditions, but knowledge on somatic growth regulation is still unclear. Growth hormone (GH)/insulin-like growth factor I (IGF-I) axis is the key regulator of somatic growth in vertebrates. Two types of growth hormone receptors have been described in teleost fish, named GH receptor type 1 (GHR1) and type 2 (GHR2). In addition, isoforms of these receptors lacking part of the intracellular region have been described. The aim of this study was to evaluate the somatic growth, liver histology and changes in the GH/IGF-I axis after 4 weeks of food deprivation in C. dimerus. Four-week fasted fish showed reductions in specific growth rates in body weight (p fish, while no changes in glucose levels were detected in plasma. The starvation protocol failed to induce changes in GH mRNA levels in the pituitary and IGF-I mRNA levels in liver. In contrast, IGF-I mRNA levels in muscle decreased in fasted fish (p = 0.002). On the other hand, GHR2 (detected with primer sets designed over the extracellular and intracellular region) was upregulated by starvation both in liver and muscle (p growth both in length and body weight concomitantly with alterations on liver and muscle GHR2 and muscle IGF-I mRNA expression.

  16. Upper Paleozoic glacigenic deposits of Gondwana: Stratigraphy and paleoenvironmental significance of a tillite succession in Northern Victoria Land (Antarctica)

    Science.gov (United States)

    Cornamusini, Gianluca; Talarico, Franco M.; Cirilli, Simonetta; Spina, Amalia; Olivetti, Valerio; Woo, Jusun

    2017-08-01

    Late Paleozoic glacial deposits are widespread in Gondwana. In Antarctica the best outcrops occur in the Central Transantarctic Mountains, Ellsworth Mountains, Pensacola Mountains, and in Southern Victoria Land, whereas they are rare and very scattered in Northern Victoria Land, which represents a linkage sector with Tasmania and eastern Australia. The aim of the present research is to define the stratigraphic setting and the environmental interpretation of a poorly studied Lower Permian glacigenic succession located near Orr Glacier in the Lanterman Range in Northern Victoria Land. It has great importance because it represents the only significant glacigenic succession for this wide area, marking and defining time and modality of a glacial-postglacial transition during the early Permian, a critical time-interval in the paleoenvironmental evolution of southern Gondwana. This succession, named here as the Lanterman Formation, lies directly on to crystalline basement, and is overlain by a thick Permian fluvial succession (Takrouna Formation). The results provided by sedimentological facies analysis and palynological analysis, integrated with a limited petrographic characterization, show a correlation framework between two isolated successions, outlining their stratigraphic architecture and subdivided into a lower glacial portion and an upper postglacial portion. The former, Asselian in age, is dominated by diamictite, sandstone, mudstone with lonestones, and carbonate deposits, suggesting repeated advance and retreat of a terrestrial glacier, with facies associations indicating environmental changes from subglacial to glaciofluvial, to glaciolacustrine. The latter is dominated by lacustrine mudstone with decreasing lonestones upward, thin bedded sandstone, conglomerate and a thick fluvial sandstone and pebbly sandstone succession at the top, signalling the transition to a fluvial system through time. The overall dataset suggests that the late Paleozoic glacigenic

  17. Application of Satellite Observations to Manage Natural Disasters in the Lake Victoria Basin

    Science.gov (United States)

    Habib, Shahid; Policelli, F.; Irwin, D.; Korme, Tesfaye; Adler, Bob; Hong, Yang

    2010-01-01

    Lake Victoria, the second largest fresh water lake in the Eastern part of Africa is a vital natural resource for the economic well being and prosperity of over 30 million people located in riparian regions of Uganda, Kenya and Tanzania. It covers a large area of about 68,870 km2 and produces a GDP of about US $30 billion per year. The region is also very much prone to natural disasters such as severe floods during heavy precipitation periods in the Eastern part of Africa. In addition to floods, the precipitation also produces large infestations of mosquito larvae due to the standing water in many areas. This further causes multiple vector borne diseases such as Malaria, Rift Valley Fever and more. These problems are of serious concern and require active and aggressive surveillance and management to minimize the loss of human and animal lives and property damage. Satellite imagery and observations along with the in situ measurements provide a great tool to analyze and study this area and inform the policy makers to make calculated policy decisions which are more beneficial to the environment. Recently, NASA and USAID have joined forces with the Regional Center for Mapping of Resources for Development (RCMRD) located in Nairobi, Kenya to utilize multiple NASA sensors such as TRMM, SRTM and MODIS to develop flood potential maps for the Lake Victoria Basin. The idea is to generate a flood forecasts and "nowcasts" that can be sent to the disaster management organizations of Uganda, Kenya, and Tanzania. Post flood event satellite imagery is becoming a common tool to assess the areas inundated by flooding. However, this work is unique undertaking by utilizing land imaging and atmospheric satellites to build credible flood potential maps. At same time, we are also studying the potential occurrence and spread of Rift Valley Fever disease based on the short term climate records and precipitation data. These activities require multi-nation coordination and agreements and

  18. A statewide review of postnatal care in private hospitals in Victoria, Australia

    Science.gov (United States)

    2010-01-01

    Background Concerns have been raised in Australia and internationally regarding the quality and effectiveness of hospital postnatal care, although Australian women receiving postnatal care in the private maternity sector rate their satisfaction with care more highly than women receiving public maternity care. In Victoria, Australia, two-thirds of women receive their maternity care in the public sector and the remainder in private health care sector. A statewide review of public hospital postnatal care in Victoria from the perspective of care providers found many barriers to care provision including the busyness of postnatal wards, inadequate staffing and priority being given to other episodes of care; however the study did not include private hospitals. The aim of this study was replicate the review in the private sector, to explore the structure and organisation of postnatal care in private hospitals and identify those aspects of care potentially impacting on women's experiences and maternal and infant care. This provides a more complete overview of the organisational structures and processes in postnatal care in all Victorian hospitals from the perspective of care providers. Methods A mixed method design was used. A structured postal survey was sent to all Victorian private hospitals (n = 19) and key informant interviews were undertaken with selected clinical midwives, maternity unit managers and obstetricians (n = 11). Survey data were analysed using descriptive statistics and interview data analysed thematically. Results Private hospital care providers report that postnatal care is provided in very busy environments, and that meeting the aims of postnatal care (breastfeeding support, education of parents and facilitating rest and recovery for women following birth) was difficult in the context of increased acuity of postnatal care; prioritising of other areas over postnatal care; high midwife-to-woman ratios; and the number and frequency of visitors. These

  19. A statewide review of postnatal care in private hospitals in Victoria, Australia

    Directory of Open Access Journals (Sweden)

    Forster Della A

    2010-05-01

    Full Text Available Abstract Background Concerns have been raised in Australia and internationally regarding the quality and effectiveness of hospital postnatal care, although Australian women receiving postnatal care in the private maternity sector rate their satisfaction with care more highly than women receiving public maternity care. In Victoria, Australia, two-thirds of women receive their maternity care in the public sector and the remainder in private health care sector. A statewide review of public hospital postnatal care in Victoria from the perspective of care providers found many barriers to care provision including the busyness of postnatal wards, inadequate staffing and priority being given to other episodes of care; however the study did not include private hospitals. The aim of this study was replicate the review in the private sector, to explore the structure and organisation of postnatal care in private hospitals and identify those aspects of care potentially impacting on women's experiences and maternal and infant care. This provides a more complete overview of the organisational structures and processes in postnatal care in all Victorian hospitals from the perspective of care providers. Methods A mixed method design was used. A structured postal survey was sent to all Victorian private hospitals (n = 19 and key informant interviews were undertaken with selected clinical midwives, maternity unit managers and obstetricians (n = 11. Survey data were analysed using descriptive statistics and interview data analysed thematically. Results Private hospital care providers report that postnatal care is provided in very busy environments, and that meeting the aims of postnatal care (breastfeeding support, education of parents and facilitating rest and recovery for women following birth was difficult in the context of increased acuity of postnatal care; prioritising of other areas over postnatal care; high midwife-to-woman ratios; and the number and

  20. Family Presence During Resuscitation (FPDR): Observational case studies of emergency personnel in Victoria, Australia.

    Science.gov (United States)

    Porter, Joanne E; Miller, Nareeda; Giannis, Anita; Coombs, Nicole

    2017-07-01

    Family Presence During Resuscitation (FPDR), although not a new concept, remains inconsistently implemented by emergency personnel. Many larger metropolitan emergency departments (ED) have instigated a care coordinator role, however these personnel are often from a non-nursing background and have therefore limited knowledge about the clinical aspects of the resuscitation. In rural emergency departments there are simply not enough staff to allocate an independent role. A separate care coordinator role, who is assigned to care for the family and not take part in the resuscitation has been well documented as essential to the successful implementation of FPDR. One rural and one metropolitan emergency department in the state of Victoria, Australia were observed and data was collected on FPDR events. The participants consisted of resuscitation team members, including; emergency trained nurses, senior medical officers, general nurses and doctors. The participants were not told that the data would be recorded around interactions with family members or team discussions regarding family involvement in the resuscitation, following ethical approval involving limited disclosure of the aims of the study. Seventeen adult presentations (Metro n=9, Rural n=8) were included in this study and will be presented as resuscitation case studies. The key themes identified included ambiguity around resuscitation status, keeping the family informed, family isolation and inter-professional communication. During 17 adult resuscitation cases, staff were witnessed communicating with family, which was often limited and isolation resulted. Family were often uninformed or separated from their family member, however when a family liaison person was available it was found to be beneficial. This research indicated that staff could benefit from a designated family liaison role, formal policy and further education. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Exploring Service Providers' Perspectives in Improving Childhood Obesity Prevention among CALD Communities in Victoria, Australia.

    Directory of Open Access Journals (Sweden)

    Sheila Cyril

    Full Text Available Childhood obesity rates have been increasing disproportionately among disadvantaged communities including culturally and linguistically diverse (CALD migrant groups in Australia due to their poor participation in the available obesity prevention initiatives. We sought to explore service providers' perceptions of the key factors influencing the participation of CALD communities in the existing obesity prevention services and the service requirements needed to improve CALD communities' participation in these services.We conducted a qualitative study using focus group discussions involving fifty-nine service providers from a range of services, who are involved in the health and wellbeing of children from CALD groups living in four socioeconomically disadvantaged areas in Victoria, Australia.Thematic analysis of the data showed three major themes including community-level barriers to CALD engagement in childhood obesity prevention services; service-level barriers to the delivery of these services; and proposed changes to current childhood obesity prevention approaches. Integrating obesity prevention messages within existing programs, better coordination between prevention and treatment services and the establishment of a childhood obesity surveillance system, were some of the important changes suggested by service providers.This study has found that low CALD health literacy, lack of knowledge of cultural barriers among service providers and co-existing deficiencies in the structure and delivery of obesity prevention services negatively impacted the participation of CALD communities in obesity prevention services. Cultural competency training of service providers would improve their understanding of the cultural influences of childhood obesity and incorporate them into the design and development of obesity prevention initiatives. Service providers need to be educated on the pre-migratory health service experiences and health conditions of CALD

  2. Prehospital management of supraventricular tachycardia in Victoria, Australia: epidemiology and effectiveness of therapies.

    Science.gov (United States)

    Smith, Gavin; McD Taylor, David; Morgans, Amee; Cameron, Peter

    2014-08-01

    The present study examined patient demographics, characteristics and the effectiveness of current prehospital supraventricular tachycardia (SVT) management by ambulance paramedics in Victoria, Australia. We conducted a retrospective study of all Victorian patients attended by paramedics between 14 February 2012 and 13 February 2013, where SVT was the initial or final diagnosis. Patients were excluded if SVT was not captured on ECG, incomplete data were recorded, or SVT began after initial assessment. Data were extracted from the VACIS(®) clinical data warehouse. Accuracy of paramedic SVT diagnosis was examined. Nine hundred and thirty-three patients were enrolled, including 882 (94.5%) adults and 564 (60.5%) women. Mean adult and paediatric (SVT in 119/123 (96.7%, 95% CI: 91.5, 99.0) of adult ECG strips examined. There were 273/882 (31.0%) patients who spontaneously reverted while in paramedic care. Valsalva manoeuvre was undertaken by 212/882 (24.0%) patients and reverted the SVT in 99/358 (27.7%) attempts. Verapamil was administered to 38/882 (4.3%) patients and reverted 33 (86.8%). Aramine was administered to 43/882 (4.9%) patients and 35 reverted following administration (81.4%). Synchronised cardioversion (70 J) reverted four patients at first attempt. Ultimately, 438 (49.7%) patients remained in SVT on arrival at hospital. Patient characteristics associated with SVT are more likely to be middle-aged women with a history of hypertension and hypercholesterolaemia. Therapies were underutilised leading to reduced clinical guideline effectiveness. Where therapies were instigated, reversion rates are greater than previously reported. © 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  3. Influence of voluntary standards and design modifications on trampoline injury in Victoria, Australia.

    Science.gov (United States)

    Ashby, Karen; Eager, David; D'Elia, Angelo; Day, Lesley

    2015-10-01

    To examine the influence of the voluntary Australian trampoline standard (AS 4989-2006) and market-driven design modifications on relevant trampoline injuries. Trend and intervention analysis on frequencies and proportions of hospital-treated trampoline-related injury in Victoria, Australia, extracted from the Victorian Emergency Minimum Dataset from 1 July 1999 to 30 June 2013. The injuries relevant to the AS were contact with spring and frame, and multiple-user injury. Falls from trampolines were relevant for netted trampolines, a market-driven modification. Frequency of all trampoline injuries increased by 11.4% (95% CI 10.0% to 11.7%) on average each year. Spring and frame, and fall injuries increased to a lesser extent (8.7%, 95% CI 6.9% to 9.8% and 7.3%, 95% CI 5.8% to 8.3%, respectively). Multiple-user injuries increased by 21.0% (95% CI 16.3% to 21.9%). As a proportion of all trampoline injuries, spring and frame injury and falls injury decreased, while multiple-user injuries increased. The intervention analysis showed no significant change in spring and frame injuries associated with the AS (p=0.17). A significant increase was found for multiple-user injuries (p=0.01), in particular for the 0-year to 4-year age group (ptrampolines appear to be associated with a decrease in falls from trampolines but an increase in injuries to multiple users. A mandated trampoline safety standard and a safety campaign including warnings about multiple users is recommended. Continued monitoring of injury data will be required. 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.

  4. Modelling density-dependent flow and solute transport at the Lake Tutchewop saline disposal complex, Victoria

    Science.gov (United States)

    Simmons, Craig T.; Narayan, Kumar A.

    1998-05-01

    Intercepted saline groundwaters and drainage effluent from irrigation are commonly stored in both natural and artificial saline disposal basins throughout the Murray-Darling Basin of Australia. Their continued use as wastewater evaporation sites requires an understanding of existing groundwater dynamics. The useful of individual basins, their sustainability and possible environmental impacts remain largely unknown. In this work, the movement of salt to the underlying groundwater system from Lake Tutchewop, a saline disposal complex in north-central Victoria, was modelled in cross-section. Due to the salinity contrast between the hypersaline basin waters and the regional groundwater, it was necessary to simulate density-dependent flow behaviour. Under certain conditions, these density-stratified systems may become unstable leading to the onset of convective behaviour, which greatly increases the movement of salt from the basin to the groundwater system. Modelled concentration profiles in the aquifer system and calculated seepage rates from the basin show that Lake Tutchewop is stable under its present operating regime. The downward movement of salt is mainly controlled by diffusion and dispersion. The calibrated model was used to assess the impact of several management scenarios using time-dependent boundary conditions for lake salinity and water levels. The influence of heterogeneous basin linings on ensuing salt flux rates is examined, and results show that increased solute transport will occur under such conditions. A sensitivity analysis performed on governing variables showed that salt fluxes were most sensitive to lake salinity levels. A solute Rayleigh number defined in terms of basin salinity and hydrogeologic parameters is seen to be an effective tool for predicting the long term behaviour of such saline disposal basins. The models and concepts developed in this work may find application in the design and management of saline disposal complexes.

  5. Making medicine; producing pleasure: A critical examination of medicinal cannabis policy and law in Victoria, Australia.

    Science.gov (United States)

    Lancaster, Kari; Seear, Kate; Ritter, Alison

    2017-11-01

    Several jurisdictions around the world have introduced policies and laws allowing for the legal use of cannabis for therapeutic purposes. However, there has been little critical discussion of how the object of 'medicinal cannabis' is enacted in policy and practice. Informed by Carol Bacchi's poststructuralist approach to policy analysis and the work of science and technology studies scholars, this paper seeks to problematise the object of 'medicinal cannabis' and examine how it is constituted through governing practices. In particular, we consider how the making of the object of 'medicinal cannabis' might constrain or enact discourses of pleasure. As a case example, we take the Victorian Law Reform Commission's review of law reform options to allow people in the Australian state of Victoria to be treated with medicinal cannabis. Through analysis of this case example, we find that although 'medicinal cannabis' is constituted as a thoroughly medical object, it is also constituted as unique. We argue that medicinal cannabis is enacted in part through the production of another object (so-called 'recreational cannabis') and the social and political meanings attached to both. Although both 'substances' are constituted as distinct, 'medicinal cannabis' relies on the 'absent presence' of 'recreational cannabis' to define and shape what it is. However, we find that contained within this rendering of 'medicinal cannabis' are complex enactments of health and wellbeing, which open up discourses of pleasure. 'Medicinal cannabis' appears to challenge the idea that the effects of 'medicine' cannot be understood in terms of pleasure. As such, the making of 'medicinal cannabis' as a medical object, and its invocation of broad notions of health and wellbeing, expand the ways in which drug effects can be acknowledged, including pleasurable and desirable effects, helping us to think differently about both medicine and other forms of drug use. Copyright © 2017 Elsevier B.V. All rights

  6. Subglacial Calcites from Northern Victoria Land: archive of Antarctic volcanism in the Last Glacial Maximum

    Science.gov (United States)

    Frisia, Silvia; Weirich, Laura; Hellstrom, John; Borsato, Andrea; Golledge, Nicholas R.; Anesio, Alexandre M.; Bajo, Petra; Drysdale, Russell N.; Augustinus, Paul C.; Barbante, Carlo; Cooper, Alan

    2017-04-01

    Subglacial carbonates bear similarities to stalagmites in their fabrics and the potential to obtain precise chronologies using U-series methods. Their chemical properties also reflect those of their parent waters, which, in contrast to stalagmites, are those of subglacial meltwaters. In analogy to speleothems, stable Carbon isotope ratios and trace elements such as Uranium, Iron and Manganese provide the opportunity to investigate ancient extreme environments without the need to drill through thousands of metres of ice. Sedimentological, geochemical and microbial evidence preserved in LGM subglacial calcites from Northern Victoria Land, close to the East Antarctic Ice Sheet margin, allow us to infer that subglacial volcanism was active in the Trans Antarctic Mountain region and induced basal ice melting. We hypothesize that a meltwater reservoir was drained and injected into interconnected basal pore systems where microbial processes enhanced bedrock weathering and, thus, released micronutrients. Volcanic influence is supported by the presence of fluorine (F) and sulphur in sediment-laden calcite layers containing termophilic species. Notably, calcite δ13C points to dissolved inorganic carbon evolved from subglacial metabolic processes. Once transported to the sea, soluble iron likely contributed to fertilizing the Southern Ocean and CO2 drawdown. This is the first well-dated evidence for LGM volcanism in Antarctica, which complements the record of volcanic eruptions retrieved from Talos Dome ice core, and supports the hypothesis of large-scale volcanism as an important driver of climate change. We conclude that subglacial carbonates are equivalent to speleothems in their palaeoclimate potential and may become a most useful source of information of ecosystems and processes at peak glacials in high altitude/high latitude settings.

  7. Individual and community factors for railway suicide: a matched case-control study in Victoria, Australia.

    Science.gov (United States)

    Too, Lay San; Spittal, Matthew J; Bugeja, Lyndal; McClure, Roderick; Milner, Allison

    2016-06-01

    This study aims to simultaneously examine individual- and community-level factors associated with railway suicide. We performed a case-control study in Victoria, Australia between 2001 and 2012. Data on cases of railway suicide were obtained from the National Coronial Information System (a database of coronial investigations). Controls were living individuals randomly selected from the Household, Income and Labour Dynamics in Australia study, matching to cases on age groups, sex and year of exposures. A conditional logistic regression model was used to assess the individual-level and community-level influences on individual odds of railway suicide, controlling for socioeconomic status. Individual-level diagnosed mental illness increased railway suicide odds by six times [95 % confidence interval (CI) 4.5, 9.2]. Community-level factors such as living in an area with a presence of railway tracks [odds ratio (OR) 1.8, 95 % CI 1.2, 2.8], within a city (OR 3.2, 95 % CI 1.9, 5.4), and with a higher overall suicide rate (OR 1.02, 95 % CI 1.01, 1.04) were independently associated with greater individual odds of railway suicide compared to living in an area without a presence of railway tracks, outside a city, and with a relatively lower overall suicide rate. The effects of mental illness and high incidence of overall suicides are prominent, but not specific on railway suicide. The effects of presence of railway tracks and city residence suggest the importance of accessibility to the railways for individual risk of railway suicide. Prevention efforts should focus on vulnerable people live in areas with easy access to the railways.

  8. Travel Destinations and Sexual Behavior as Indicators of Antibiotic Resistant Shigella Strains--Victoria, Australia.

    Science.gov (United States)

    Lane, Courtney R; Sutton, Brett; Valcanis, Mary; Kirk, Martyn; Walker, Cathryn; Lalor, Karin; Stephens, Nicola

    2016-03-15

    Knowledge of relationships between antibiotic susceptibility of Shigella isolates and travel destination or other risk factors can assist clinicians in determining appropriate antibiotic therapy prior to susceptibility testing. We describe relationships between resistance patterns and risk factors for acquisition in Shigella isolates using routinely collected data for notified cases of shigellosis between 2008 and 2012 in Victoria, Australia. We included all shigellosis patients notified during the study period, where Shigella isolates were tested for antimicrobial sensitivity using Clinical and Laboratory Standards Institute breakpoints. Cases were interviewed to collect data on risk factors, including recent travel. Data were analyzed using Stata 13.1 to examine associations between risk factors and resistant strains. Of the 500 cases of shigellosis, 249 were associated with overseas travel and 210 were locally acquired. Forty-six of 51 isolates of Indian origin displayed decreased susceptibility or resistance to ciprofloxacin. All isolates of Indonesian origin were susceptible to ciprofloxacin. Twenty-six travel-related isolates were resistant to all tested oral antimicrobials. Male-to-male sexual contact was the primary risk factor for 80% (120/150) of locally acquired infections among adult males, characterized by distinct periodic Shigella sonnei outbreaks. Clinicians should consider travel destination as a marker for resistance to common antimicrobials in returning travelers, where severe disease requires empirical treatment prior to receipt of individual sensitivity testing results. Repeated outbreaks of locally acquired shigellosis among men who have sex with men highlight the importance of prevention and control measures in this high-risk group. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  9. Dual diagnosis discourse in Victoria Australia: the responsiveness of mental health services.

    Science.gov (United States)

    Roberts, Bridget M; Maybery, Darryl

    2014-01-01

    In recent decades, psychiatric services have been challenged to be more responsive to patients' coexisting problems, in particular those concerning substance use. In Australia this has been referred to as a "No Wrong Door" approach. This paper explores the meanings of this move for the acute mental health sector, including attitudes toward a No Wrong Door approach to people with a dual diagnosis of mental illness and substance use disorder.   This qualitative study involved a review of the research literatures, analysis of policy documents, and interviews with 19 key informants in a case study of the State of Victoria, Australia.   The analysis resulted in two broad themes surrounding the implications of dual diagnosis discourse for the mental health sector. The first involves progress regarding the concept of No Wrong Door with subthemes including interprofessional cultural conflicts, intersectoral professional status issues, terminology, problem definition, perspectives on serious mental illness, the role of the client, and pharmacological treatment. The second overarching theme focuses upon informants' thoughts on future directions for the sector and highlights divided opinion on the implications of dual diagnosis discourse for the mental health service and social care systems.   While the perspectives on system change and multiple issues such as resource concerns and cultural clashes are presented here, the informants in this study also gave clear guidance for the future of dual diagnosis work in the mental health sector (e.g., focusing on orienting services toward consumer strengths and recovery), along with recommendations for future research. This paper contributes to the small body of qualitative research on the history and course of efforts to develop appropriate practice in mental health services with regard to patients who have substance use problems and other mental health disorders.

  10. Population surveys of Nile crocodiles (Crocodylus niloticus in the Murchison Falls National Park, Victoria Nile, Uganda

    Directory of Open Access Journals (Sweden)

    Behangana Mathias

    2017-12-01

    Full Text Available 1. A 12-month-long survey (April 2013 to March 2014 for Nile crocodiles (Crocodylus niloticus was conducted along a section of the Victoria Nile/Ramsar site of Murchison Falls National Park, in order to update the historic information on crocodile populations in the area, locating nesting areas, determining seasonality patterns and habitat use, and assess the current abundance and the population size trends since the 1960s. The methods employed included visual encounter surveys, transect counts and opportunistic methods, by using boats. 2. In general, there were diurnal and seasonal fluctuations in the number of crocodile sightings. The crocodile sightings peaked between the months of June and August, with the highest mean number of sightings encountered on any single day being 67 (in July 2013, and the second peak was between January and March with the highest mean of 118 recorded in January 2014. The second peak also coincided with the crocodile breeding season. This clearly shows that the distribution of the sub-population sampled followed a climatic regime. 3. Crocodiles were observed most frequently in water (37%. Grassy banks, islands, river mouths and sandy banks constituted about 47% of the habitats utilised by the crocodile population. Although basking was the most frequent type of activity performed by crocodiles (50% over the entire survey period, their key activities varied significantly from month to month. Nesting was very visible during the last quarter of the year and the first quarter of the New Year. 4. There was a clear decline of the abundance of crocodiles in this population between 1960s and nowadays. This declining trend was obvious also taking into account the various survey methodologies employed over the decades.

  11. Governance of quality of care: a qualitative study of health service boards in Victoria, Australia.

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    Bismark, Marie M; Studdert, David M

    2014-06-01

    To describe the engagement of health service boards with quality-of-care issues and to identify factors that influence boards' activities in this area. We conducted semistructured interviews with 35 board members and executives from 13 public health services in Victoria, Australia. Interviews focused on the role currently played by boards in overseeing quality of care. We also elicited interviewees' perceptions of factors that have influenced their current approach to governance in this area. Thematic analysis was used to identify key themes from interview transcripts. Virtually all interviewees believed boards had substantial opportunities to influence the quality of care delivered within the service, chiefly through setting priorities, monitoring progress, holding staff to account and shaping culture. Perceived barriers to leveraging this influence included insufficient resources, gaps in skills and experience among board members, inadequate information on performance and regulatory requirements that miss the mark. Interviewees converged on four enablers of more effective quality governance: stronger regional collaborations; more tailored board training on quality issues; smarter use of reporting and accreditation requirements; and better access to data that was reliable, longitudinal and allowed for benchmarking against peer organisations. Although health service boards are eager to establish quality of care as a governance priority, several obstacles are blocking progress. The result is a gap between the rhetoric of quality governance and the reality of month-to-month activities at the board level. The imperative for effective board-level engagement in this area cannot be met until these barriers are addressed. 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.

  12. Impacts of reclaimed water irrigation on soil antibiotic resistome in urban parks of Victoria, Australia.

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    Han, Xue-Mei; Hu, Hang-Wei; Shi, Xiu-Zhen; Wang, Jun-Tao; Han, Li-Li; Chen, Deli; He, Ji-Zheng

    2016-04-01

    The effluents from wastewater treatment plants have been recognized as a significant environmental reservoir of antibiotics and antibiotic resistance genes (ARGs). Reclaimed water irrigation (RWI) is increasingly used as a practical solution for combating water scarcity in arid and semiarid regions, however, impacts of RWI on the patterns of ARGs and the soil bacterial community remain unclear. Here, we used high-throughput quantitative PCR and terminal restriction fragment length polymorphism techniques to compare the diversity, abundance and composition of a broad-spectrum of ARGs and total bacteria in 12 urban parks with and without RWI in Victoria, Australia. A total of 40 unique ARGs were detected across all park soils, with genes conferring resistance to β-lactam being the most prevalent ARG type. The total numbers and the fold changes of the detected ARGs were significantly increased by RWI, and marked shifts in ARG patterns were also observed in urban parks with RWI compared to those without RWI. The changes in ARG patterns were paralleled by a significant effect of RWI on the bacterial community structure and a co-occurrence pattern of the detected ARG types. There were significant and positive correlations between the fold changes of the integrase intI1 gene and two β-lactam resistance genes (KPC and IMP-2 groups), but no significant impacts of RWI on the abundances of intI1 and the transposase tnpA gene were found, indicating that RWI did not improve the potential for horizontal gene transfer of soil ARGs. Taken together, our findings suggested that irrigation of urban parks with reclaimed water could influence the abundance, diversity, and compositions of a wide variety of soil ARGs of clinical relevance. Irrigation of urban parks with treated wastewater significantly increased the abundance and diversity of various antibiotic resistance genes, but did not significantly enhance their potential for horizontal gene transfer. Copyright © 2015 Elsevier

  13. First molecular characterisation of Cryptosporidium and Giardia from Bubalus bubalis (water buffalo) in Victoria, Australia.

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    Abeywardena, Harshanie; Jex, Aaron R; von Samson-Himmelstjerna, Georg; Haydon, Shane R; Stevens, Melita A; Gasser, Robin B

    2013-12-01

    We conducted a molecular epidemiological survey of Cryptosporidium and Giardia from Bubalus bubalis (water buffalo) on two extensive farms (450 km apart) in Victoria, Australia. Faecal samples (n=476) were collected from different age groups of water buffalo at two time points (six months apart) and tested using a PCR-based mutation scanning-targeted sequencing-phylogenetic approach, employing markers within the small subunit of ribosomal RNA (designated pSSU) and triose phosphate isomerase (ptpi) genes. Based on pSSU data, Cryptosporidium parvum, Cryptosporidium bovis and Cryptosporidium genotypes 1, 2 (each 99% similar genetically to Cryptosporidium ryanae) and 3 (99% similar to Cryptosporidium suis) were detected in two (0.4%), one (0.2%), 38 (8.0%), 16 (3.4%) and one (0.2%) of the 476 samples tested, respectively. Using ptpi, Giardia duodenalis assemblages A and E were detected in totals of 56 (11.8%) and six (1.3%) of these samples, respectively. Cryptosporidium was detected on both farms, whereas Giardia was detected only on farm B, and both genera were detected in 1.5% of all samples tested. The study showed that water buffaloes on these farms excreted C. parvum and/or G. duodenalis assemblage A, which are consistent with those found in humans, inferring that these particular pathogens are of zoonotic significance. Future work should focus on investigating, in a temporal and spatial manner, the prevalence and intensity of such infections in water buffaloes in various geographical regions in Australia and in other countries. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Factors associated with sickness certification of injured workers by General Practitioners in Victoria, Australia

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    Rasa Ruseckaite

    2016-04-01

    Full Text Available Abstract Background Work-related injuries resulting in long-term sickness certification can have serious consequences for injured workers, their families, society, compensation schemes, employers and healthcare service providers. The aim of this study was to establish what factors potentially are associated with the type of sickness certification that General Practitioners (GPs provide to injured workers following work-related injury in Victoria, Australia. Methods This was a retrospective population-based cohort study was conducted for compensation claims lodged by adults from 2003 to 2010. A logistic regression analysis was performed to assess the impact of various factors on the likelihood that an injured worker would receive an alternate/modified duties (ALT, n = 28,174 vs. Unfit for work (UFW, n = 91,726 certificate from their GP. Results A total of 119,900 claims were analysed. The majority of the injured workers were males, mostly age of 45-54 years. Nearly half of the workers (49.9 % with UFW and 36.9 % with ALT certificates had musculoskeletal injuries. The multivariate regression analysis revealed that for most occupations older men (55-64 years were less likely to receive an ALT certificate, (OR = 0.86, (95%CI, 0.81 – 0.91. Workers suffering musculoskeletal injuries or occupational diseases were nearly twice or three times at higher odds of receiving an ALT certificate when compared to fractures. Being seen by a GP experienced with workers’ compensation increased the odds of receiving ALT certificate (OR = 1.16, (95%CI, 1.11 – 1.20. Occupation and industry types were also important factors determining the type of certificate issued to the injured worker. Conclusions This study suggests that specific groups of injured workers (i.e. older age, workers with mental health issues, in rural areas are less likely to receive ALT certificates.

  15. Medical review licensing outcomes in drivers with visual field loss in Victoria, Australia

    Science.gov (United States)

    Muir, Carlyn; Charlton, Judith L; Odell, Morris; Keeffe, Jill; Wood, Joanne; Bohensky, Megan; Fildes, Brian; Oxley, Jennifer; Bentley, Sharon; Rizzo, Matthew

    2017-01-01

    Background Good vision is essential for safe driving and studies have associated visual impairment with an increased crash risk. Currently, there is little information about the medical review of drivers with visual field loss. This study examines the prevalence of visual field loss among drivers referred for medical review in one Australian jurisdiction and investigates factors associated with licence outcome in this group. Methods A random sample of 10,000 (31.25 per cent) medical review cases was extracted for analysis from the Victorian licensing authority. Files were screened for the presence of six visual field-related medical conditions. Data were captured on a range of variables, including referral source, age, gender, health status, crash history and licence outcome. Prevalence analyses were univariate and descriptive. Logistic regression was used to assess factors associated with licence outcomes in the visual field loss group. Results Approximately 1.9 per cent of the 10,000 medical review cases screened had a visual field loss condition identified (n=194). Among the visual field loss group, 57.2 per cent were permitted to continue driving (conditional/unconditional licence). Primary referral sources were the police, self-referrals and general medical practitioners. Key factors associated with licence test outcomes were visual field condition, age group, crash involvement and referral to the Driver Licensing Authority’s Medical Advisors. Those who were younger had a crash involvement triggering referral and those who were referred to the Medical Advisors were more likely to have a positive licensing outcome. Conclusion The evidence base for making licensing decisions is complicated by the variable causes, patterns, progressions and measuring technologies for visual field loss. This study highlighted that the involvement of an expert medical advisory service in Victoria resulted in an increased likelihood that drivers with visual field loss will be

  16. Sleep-Related Infant Deaths in Victoria: A Retrospective Case Series Study.

    Science.gov (United States)

    Bugeja, Lyndal; Dwyer, Jeremy; McIntyre, Sara-Jane; Young, Jeanine; Stephan, Karen Lesley; McClure, Roderick John

    2016-05-01

    There is general agreement that in some circumstances, sharing a sleep surface of any kind with an infant increases the risk of sudden unexpected death in infancy. There is a paucity of research conducted in Australia examining this issue. This study examines the frequency and distribution of sleep-related infant deaths in a defined population, and reports the proportion that occurred in the context of bed-sharing. A retrospective population-based case series study was conducted of infants (≤365 days) who died in a sleeping context during the period 1 January 2008 to 31 December 2010 in the state of Victoria, Australia. Information about the infant, caregiver, sleeping environment and bed-sharing was collected from a review of the coroner's death investigation record. During the 3-year study period, 72 infant deaths occurred in a sleeping context. Of these, 33 (45.8 %) occurred in the context of bed-sharing: n = 7 in 2008; n = 11 in 2009; and n = 15 in 2010. Further analysis of the 33 deaths occurring in the context of bed-sharing showed that in this group, bed-sharing was largely intentional, habitual and most often involved the mother as one of the parties. Given the case series nature of the study design, a causal relationship between bed-sharing and infant death could not be inferred. However the fact that nearly half of all sleep-related deaths occurred in the context of bed-sharing, provides strong support for the need to undertake definitive analytic studies in Australia so that evidence-based advice can be provided to families regarding the safety of bed-sharing practices.

  17. Strategic Actions for Increasing the Submission of Digital Cadastral Data by the Surveying Industry Based on Lessons Learned from Victoria, Australia

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    Hamed Olfat

    2018-02-01

    Full Text Available ePlan, as a digital cadastral data initiative, is a collaborative program between the land authorities and the surveying industry which aims to replace paper and PDF cadastral plans and surveys with digital data. ePlan is currently operational in Australia, New Zealand and Singapore. ePlan was introduced in the State of Victoria in 2011 and has been operational in this jurisdiction for 2D plans since 2013. On average, one ePlan application is currently submitted to a digital plan lodgment portal every two weeks. The low uptake of ePlan is caused by several technical and non-technical challenges. This paper provides an overview of cadastral information transitioning from paper to digital in Victoria. The research methodology to identify the challenges in Victoria for the adoption of ePlan is then described. This is followed by a discussion on the identified challenges. The paper then proposes a generic framework of strategic actions to increase the uptake of digital cadastral data based on the lessons learned from Victoria. The initiatives suggested by this framework to address the ePlan challenges in Victoria and increase its uptake are also introduced. The paper concludes with a direction for future research.

  18. Geologic map and structural analysis of the Victoria quadrangle (H2) of Mercury based on NASA MESSENGER images

    Science.gov (United States)

    Galluzzi, V.; Di Achille, G.; Ferranti, L.; Rothery, D. A.; Palumbo, P.

    The first stratigraphic and geologic study of Mercury was released by Trask & Guest (1975) followed by Spudis & Guest (1988, and references therein), whose work was based on the images taken by Mariner 10 covering 42% of the total surface of Mercury. The planet has been officially divided into fifteen quadrangles: 2 polar, 5 equatorial and 8 at midlatitudes. Quadrangle H2 (= Hermes sheet n.2), named ``Victoria'' (20oN - 65oN Lon.; 270oE - 0o Lat.), was partially mapped by McGill & King (1983), though a wide area (˜64%) remained unmapped due to the lack of imagery. Following the terrain units recognized and described by the above authors, we have produced a geologic map of the entire quadrangle using MESSENGER (MErcury Surface, Space ENvironment, GEochemistry and Ranging) images. The images taken by the Mercury Dual Imaging System (MDIS) Wide Angle Camera (WAC) and Narrow Angle Camera (NAC) allowed us to map geologic and tectonic features in much greater detail than the previously published map (mapping scale range between 1:300k and 1:600k). We classified craters larger than 20 km using three relative age classes, which are a simplification of the past five degradation classes defined by McCauley et al. (1981). Victoria quadrangle is characterized by a localized N-S thrust array constituted by Victoria Rupes, Endeavour Rupes and Antoniadi Dorsum to the East and by a more diffuse system of NE-SW oriented fault arrays to the West: the two systems seem to be separated by a tectonic bulge. The Victoria-Endeavour-Antoniadi system has been interpreted as a fold-and-thrust belt by Byrne et al. (2014) and a previous study made on craters cross-cut by its thrusts reveals fault dips of 15-20o and a near dip slip motion (Galluzzi et al., 2015). This geologic map has the aim to build a regional model of its structural framework. Deciphering the geological setting of this quadrangle will bring important insights for understanding the tectonic evolution of the whole planet

  19. Uncertainties in Flow-Duration-Frequency Relationships of High and Low Flow Extremes in Lake Victoria Basin

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    Charles Onyutha; Patrick Willems

    2013-01-01

    This paper focuses on uncertainty analysis to aid decision making in applications of statistically modeled flow-duration-frequency (FDF) relationships of both daily high and low flows. The analysis is based on 24 selected catchments in the Lake Victoria basin in Eastern Africa. The FDF relationships were derived for aggregation levels in the range 1–90 days for high flows and 1–365 days for low flows. The validity of the projected FDF quantiles for high return periods T was checked using grow...

  20. Serotonergic outcome, stress and sexual steroid hormones, and growth in a South American cichlid fish fed with an L-tryptophan enriched diet.

    Science.gov (United States)

    Morandini, Leonel; Ramallo, Martín Roberto; Moreira, Renata Guimarães; Höcht, Christian; Somoza, Gustavo Manuel; Silva, Ana; Pandolfi, Matías

    2015-11-01

    Reared animals for edible or ornamental purposes are frequently exposed to high aggression and stressful situations. These factors generally arise from conspecifics in densely breeding conditions. In vertebrates, serotonin (5-HT) has been postulated as a key neuromodulator and neurotransmitter involved in aggression and stress. The essential amino acid L-tryptophan (trp) is crucial for the synthesis of 5-HT, and so, leaves a gateway for indirectly augmenting brain 5-HT levels by means of a trp-enriched diet. The cichlid fish Cichlasoma dimerus, locally known as chanchita, is an autochthonous, potentially ornamental species and a fruitful laboratory model which behavior and reproduction has been studied over the last 15years. It presents complex social hierarchies, and great asymmetries between subordinate and dominant animals in respect to aggression, stress, and reproductive chance. The first aim of this work was to perform a morphological description of chanchita's brain serotonergic system, in both males and females. Then, we evaluated the effects of a trp-supplemented diet, given during 4weeks, on brain serotonergic activity, stress and sexual steroid hormones, and growth in isolated specimens. Results showed that chanchita's brain serotonergic system is composed of several populations of neurons located in three main areas: pretectum, hypothalamus and raphe, with no clear differences between males and females at a morphological level. Animals fed with trp-enriched diets exhibited higher forebrain serotonergic activity and a significant reduction in their relative cortisol levels, with no effects on sexual steroid plasma levels or growth parameters. Thus, this study points to food trp enrichment as a "neurodietary'' method for elevating brain serotonergic activity and decreasing stress, without affecting growth or sex steroid hormone levels. Copyright © 2015 Elsevier Inc. All rights reserved.