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Sample records for alces alces gigas

  1. Anti-Brucella Antibodies in Moose (Alces alces gigas), Muskoxen (Ovibos moschatus), and Plains Bison (Bison bison bison) in Alaska, USA.

    PubMed

    Nymo, Ingebjørg Helena; Beckmen, Kimberlee; Godfroid, Jacques

    2016-01-01

    We used an indirect enzyme-linked immunosorbent assay (iELISA) and the rose bengal test (RBT) to test for anti-Brucella antibodies in moose (Alces alces gigas), muskoxen (Ovibos moschatus), and plains bison (Bison bison bison) from various game management units (GMUs) in Alaska, US, sampled from 1982 to 2010. A portion of the sera had previously been tested with the standard plate test (SPT), the buffered Brucella antigen (BBA) card test, and the card test (CARD). No antibody-positive plains bison were identified. Anti-Brucella antibodies were detected in moose (iELISA, n=4/87; RBT, n=4/87; SPT, n=4/5; BBA, n=4/4) from GMU 23 captured in 1992, 1993, and 1995 and in muskoxen (iELISA, n=4/52; RBT, n=4/52; CARD, n=4/35) from GMUs 26A and 26B captured in 2004, 2006, and 2007. A negative effect of infection on the health of individuals of these species is probable. The presence of antibody-positive animals from 1992 to 2007 suggests presence of brucellae over time. The antibody-positive animals were found in northern Alaska, an area with a historically higher prevalence of Brucella-positive caribou, and a spillover of Brucella suis biovar 4 from caribou may have occurred. Brucella suis biovar 4 causes human brucellosis, and transmission from consumption of moose and muskoxen is possible.

  2. Complete mitochondrial genome sequence of Ussurian moose, Alces alces cameloides.

    PubMed

    Liu, Hui; Jiang, Guangshun

    2016-11-01

    Ussurian moose (Alces alces cameloides) in Northeast China, which is on the southmost edge of the species' Eurasian range, are facing dramatic decline in population size and distribution areas. We undertook the first sequencing of the entire mitogenome of Ussurian moose, which is thought as the oldest moose subspecies to better understand the evolutionary history of this circumboreal sole extant species. The mitogenome is 16,418 bp in length, consisting of two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, 13 protein-coding genes, and one control region. The overall base composition is A: 33.7%, T: 30.1%, C: 23.2%, and G: 13.0%, with a much higher A + T content. The phylogenetic tree of moose and 10 other most closely related Cervidae species was built.

  3. Mitochondrial phylogeography of moose (Alces alces) in North America

    USGS Publications Warehouse

    Hundertmark, Kris J.; Bowyer, R. Terry; Shields, Gerald F.; Schwartz, Charles C.

    2003-01-01

    Nucleotide variation was assessed from the mitochondrial control region of North American moose (Alces alces) to test predictions of a model of range expansion by stepping-stone dispersal and to determine whether patterns of genetic variation support the current recognition of 4 subspecies. Haplotypes formed a star phylogeny indicative of a recent expansion of populations. Values of nucleotide and haplotype diversity were low continentwide but were greatest in the central part of the continent and lowest in peripheral populations. Despite low mitochondrial diversity, moose exhibited a high degree of differentiation regionally, which was not explained by isolation by distance. Our data indicate a pattern of colonization consistent with a large central population that supplied founders to peripheral populations (other than Alaska), perhaps through rare, long-distance dispersal events (leptokurtic dispersal) rather than mass dispersal by a stepping-stone model. The colonization scenario does not account for the low haplotype diversity observed in Alaska, which may be derived from a postcolonization bottleneck. Establishment of peripheral populations by leptokurtic dispersal and subsequent local adaptation may have been sufficient for development of morphological differentiation among extant subspecies.

  4. Anaplasma phagocytophilum infection in moose (Alces alces) in Norway.

    PubMed

    Pūraitė, Irma; Rosef, Olav; Paulauskas, Algimantas; Radzijevskaja, Jana

    2015-01-01

    Anaplasma phagocytophilum is a tick-borne bacterium that infects a wide range of animal species. The aim of our study was to investigate the prevalence of A. phagocytophilum in Norwegian moose Alces alces and to characterize the bacteria by sequencing of partial msp4 and 16S rRNA genes. Hunters collected spleen samples from 99 moose of different ages during 2013 and 2014 in two areas: Aust-Agder County (n = 70) where Ixodes ricinus ticks are abundant and Oppland County (n = 29) where ticks were either absent, or abundance very low. A. phagocytophilum was detected only in moose from the I. ricinus - abundant area. The overall prevalence of infection according to 16S rRNA and msp4 gene-based PCR was 41.4% and 31.4% respectively. Sequence analysis of the partial 16S rRNA and msp4 gene revealed two and eight different sequence types respectively. Four of eight msp4 sequence types determined in this study were unique, while others were identical to sequences derived from other ruminants and ticks. The present study indicates that moose could be a potential wildlife reservoir of A. phagocytophilum in Norway.

  5. Internal parasitic fauna of elk (Alces alces) in Poland.

    PubMed

    Filip, Katarzyna J; Demiaszkiewicz, Aleksander W

    2016-12-01

    The abundance of elk (Alces alces) in Poland at the beginning of 2016 reached over 28 000 individual animals. However, little is still known about health status of elk population in the country. In particular, important health issue tend to be parasitic diseases which are the most common diseases in wild animals. Special emphasis should be given to the parasitofauna of elks. Their ability to move over great distances increases the chance of parasitic infestations in new areas and transmission to other wild animals and livestock. The aim of this article is to describe the parasites occurring in elk in Poland on the basis of previous studies from the country and to compare them with data from neighboring countries. The presented review reveals that elk populations have not been examined for the presence of parasites for decades, and no recent studies in Poland have examined the parasitofauna of this animal. As such, our study shows that assessing the parasites present in elk populations remains an important area of research.

  6. A geographical cluster of malignant catarrhal fever in Moose (Alces alces)in Norway

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three cases of lethal sheep-associated malignant catarrhal fever (SA-MCF) in free-ranging moose (Alces alces) were diagnosed in Lesja, Norway, December 2008 – February 2010. The diagnosis was based on PCR identification of ovine herpesvirus 2 DNA (n=3) and typical histopathological lesions (n=1). To...

  7. Meningoencephalitis associated with disseminated sarcocystosis in a free-ranging moose (Alces alces) calf

    PubMed Central

    Ravi, Madhu; Patel, Jagdish; Pybus, Margo; Coleman, James K.; Childress, April L.; Wellehan, James F.X.

    2015-01-01

    A wild moose (Alces alces) calf was presented for necropsy due to severe neurologic signs. Histopathologic examination revealed multisystemic inflammation with intralesional mature and immature schizonts. Schizonts in the brain reacted positively to Sarcocystis spp. polyclonal antibodies. Gene sequencing of PCR-amplified DNA identified the species as Sarcocystis alceslatrans. PMID:26246636

  8. Resurrection and redescription of Varestrongylus alces (Nematoda; Protostrongylidae), a lungworm of Eurasian elk (Alces alces), with a report on associated pathology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Varestrongylus alces Demidova & Naumitscheva, 1953 is resurrected for protostrongylid nematodes of Eurasian elk in Europe. Descriptions of males (11.36-16.95 mm) and females (16.25- 21.52 mm) are based on specimens collected from the terminal bronchioles in the lungs of Eurasian elk, Alces alces (L...

  9. [The role of the Urals in the genetic diversity of the European moose subspecies (Alces alces alces)].

    PubMed

    Kholodova, M V; Korytin, N S; Bol'shakov, V N

    2014-01-01

    The genetic diversity of the Uralian moose population and the role of the Ural region in the phylogeographic structure of the European moose were evaluated based on sequence polymorphisms of the mtDNA control region. The nucleotide diversity of the Ural moose was low, whereas haplotype diversity was rather high. It was found that the haplotype pool of the Ural moose reflects both the unique features of their mitochondrial lineages and their connection with Alces alces alces populations of Europe and West Siberia. The structure of median networks and the territorial haplotype distribution support the hypothesis that the mitochondrial lineages typical for this part of the European moose area originate from a late Pleistocene refugium that was located in the Urals.

  10. Complete mitochondrial genome of a Wild Amur Moose (Alces alces cameloides).

    PubMed

    Yu, Yanze; Feng, Yuan; Wang, Hongcheng; Yang, Yong; Duan, Yubao; Zhou, Zhengyan; Zhang, Minghai

    2016-11-01

    In this study, the complete mitochondrial genome (mt DNA) of Amur Moose (Alces alces cameloides) was sequenced, using muscle tissue obtained from a male Amur moose. The total length of the mitochondrial genome is 16,305 bp. The genome structure of Amur moose is similar to other moose and it contains 12S rRNA gene, 16S rRNA gene, 22 tRNA genes, 13 protein-coding genes, and 1 control region.

  11. Serosurvey for antibodies against Salmonella species in free-ranging moose (Alces alces) from Norway.

    PubMed

    Aschfalk, Ansgar; Hundertmark, Kris J; Bendiksen, Heidi R; Arnemo, Jon M; Denzin, Nicolai

    2003-01-01

    An indirect ELISA was developed as a tool for surveillance of antibodies against Salmonella sp. in free-ranging moose (Alces alces) in Norway. Serum samples from 303 clinically healthy moose sampled between 1993-2000 were examined. Anti-Salmonella antibodies were detected in samples from 6 individuals (1.98%). This is the first evidence of Salmonella-seropositive free-ranging moose. Possible sources and transmission routes of Salmonella comprising environment, wildlife and man are discussed.

  12. The occurrence and morphology of a lateral metatarsal splint bone in moose (Alces alces).

    PubMed

    Silvia, William J; Peterson, Rolf O; Silvia, William F; Vucetich, John A; Silvia, Alexander W

    2011-02-01

    Moose (Alces alces) appear to be different from most other cervids in that a well-developed metatarsal splint bone is present. It is found apposed to the plantolateral portion of the cannon bone in over 70 % of adults. It averages 3.3 mm in width and extends about 22% of the total length of the metatarsal. It may be derived through calcification of connective tissue or by elongation of the vestigial metatarsal V.

  13. The alc-GR system: a modified alc gene switch designed for use in plant tissue culture.

    PubMed

    Roberts, Gethin R; Garoosi, G Ali; Koroleva, Olga; Ito, Masaki; Laufs, Patrick; Leader, David J; Caddick, Mark X; Doonan, John H; Tomsett, A Brian

    2005-07-01

    The ALCR/alcA (alc) two-component, ethanol-inducible gene expression system provides stringent control of transgene expression in genetically modified plants. ALCR is an ethanol-activated transcription factor that can drive expression from the ALCR-responsive promoter (alcA). However, the alc system has been shown to have constitutive expression when used in plant callus or cell suspension cultures, possibly resulting from endogenous inducer produced in response to lowered oxygen availability. To widen the use of the alc system in plant cell culture conditions, the receptor domain of the rat glucocorticoid receptor (GR) was translationally fused to the C terminus of ALCR to produce ALCR-GR, which forms the basis of a glucocorticoid-inducible system (alc-GR). The alc-GR switch system was tested in tobacco (Nicotiana tabacum) Bright Yellow-2 suspension cells using a constitutively expressed ALCR-GR with four alternative alcA promoter-driven reporter genes: beta-glucuronidase, endoplasmic reticulum-targeted green fluorescent protein, haemagglutinin, and green fluorescent protein-tagged Arabidopsis (Arabidopsis thaliana) Arath;CDKA;1 cyclin-dependent kinase. Gene expression was shown to be stringently dependent on the synthetic glucocorticoid dexamethasone and, in cell suspensions, no longer required ethanol for induction. Thus, the alc-GR system allows tight control of alcA-driven genes in cell culture and complements the conventional ethanol switch used in whole plants.

  14. The infection of reintroduced ruminants - Bison bonasus and Alces alces - with Anaplasma phagocytophilum in northern Poland.

    PubMed

    Karbowiak, Grzegorz; Víchová, Bronislava; Werszko, Joanna; Demiaszkiewicz, Aleksander W; Pyziel, Anna M; Sytykiewicz, Hubert; Szewczyk, Tomasz; Peťko, Branislav

    2015-12-01

    The north-eastern part of Poland is considered an area of high risk for infection with tick-borne diseases, including with human granulocytic ehrlichiosis (HGE) agents. The etiological agent of HGE is Anaplasma phagocytophilum. As the animal reservoir for A. phagocytophilum in the environment serve the species from Cervidae and Bovidae families. European bison (Bison bonasus) and elk (Alces alces) are the big ruminant species, reintroduced to the forests of Middle Europe after many decades of absence. In the foci of zoonotic diseases they are able to play a role as natural reservoir to pathogens, however, their status as protected animals means their study has been rare and fragmentary. The studies of B. bonasus were conducted in Białowieża Primeval Forest and A. alces in Biebrza National Park. PCR amplifications were performed using primers amplifing the end of the groES gene, the intergenic spacer and approximately two-thirds of the groEL gene in the first round, and primers that span a 395-bp region of the groEL gene were used in the second round. The positive results were obtained in B. bonasus and A. alces, the prevalence of infection was 66.7 and 20.0%, respectively. Randomly selected samples were sequenced, sequences were compared with GenBank entries using Blast N2.2.13 and determined as A. phagocytophilum. The results presented herein are the first record of the presence of Anaplasma phagocytophilum in A. alces, and at the same time confirm the previous observations regarding the infection of B. bonasus with A. phagocytophilum.

  15. Postmortal radiographic diagnosis of laminitis in a captive European moose (Alces alces).

    PubMed

    Clauss, M; Keller, A; Peemöller, A; Nygrén, K; Hatt, J-M; Nuss, K

    2009-11-01

    A five year-old bull moose (Alces alces) was culled due to chronic hoof overgrowth that required frequent intervention. Radiographic examination revealed changes in phalangeal bone structure usually considered indicative for laminitis in domestic cattle; similar changes were absent in the hooves of a free-ranging moose of similar age. The captive animal had been maintained in exhibits whose flooring were much harder than the soil in natural moose habitat, and on a diet with a high proportion of easily fermentable carbohydrates. These findings indicate that chronic laminitis should be considered as a potential underlying factor for hoof overgrowth, and that measures aimed at reducing the incidence of laminitis in domestic cattle, such as the use of softer flooring and diets with a higher proportion of fibre, might have prophylactic potential in captive wild ruminants.

  16. Harvest-induced phenotypic selection in an island population of moose, Alces alces.

    PubMed

    Kvalnes, Thomas; Saether, Bernt-Erik; Haanes, Hallvard; Røed, Knut H; Engen, Steinar; Solberg, Erling J

    2016-07-01

    Empirical evidence strongly indicates that human exploitation has frequently led to rapid evolutionary changes in wild populations, yet the mechanisms involved are often poorly understood. Here, we applied a recently developed demographic framework for analyzing selection to data from a 20-year study of a wild population of moose, Alces alces. In this population, a genetic pedigree has been established all the way back to founders. We demonstrate harvest-induced directional selection for delayed birth dates in males and reduced body mass as calf in females. During the study period, birth date was delayed by 0.81 days per year for both sexes, whereas no significant changes occurred in calf body mass. Quantitative genetic analyses indicated that both traits harbored significant additive genetic variance. These results show that selective harvesting can induce strong selection that oppose natural selection. This may cause evolution of less favorable phenotypes that become maladaptive once harvesting ceases.

  17. Hematology and serum chemistry reference ranges of free-ranging moose (Alces alces) in Norway.

    PubMed

    Rostal, Melinda K; Evans, Alina L; Solberg, Erling J; Arnemo, Jon M

    2012-07-01

    Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces alces) adults, yearlings, and calves in Norway sampled from 1992-2000. Additionally, we demonstrated that both induction time and chase time were correlated with initial rectal temperature, although they were not significantly correlated with cortisol, aspartate aminotransferase, glucose, or creatine kinase. Overall, the reference ranges given here are similar to those given for American moose, with a few differences that can be attributed to environment, testing methodology, or subspecies or species status. This is the first report, to our knowledge, of reference ranges for moose in Norway.

  18. Detection of antibodies to Neospora caninum in moose (Alces alces): the first report in Europe.

    PubMed

    Moskwa, Bozena; Goździk, Katarzyna; Bień, Justyna; Kornacka, Aleksandra; Cybulska, Aleksandra; Reiterová, Katarína; Cabaj, Władysław

    2014-02-01

    Neospora caninum Dubey, Carpenter, Speer, Topper et Uggla, 1988 is a protozoan parasite originally reported as a major cause of bovine abortions worldwide. It is documented that the parasite is widely spread among non-carnivorous cervids. The purpose of this study was to investigate the seroprevalence of N. caninum in moose (Alces alces Linnaeus). Blood samples collected in 2010 and 2012 in the northeastern Poland were tested for antibodies to N. caninum by agglutination test (NAT), a commercial competitive screening enzyme-linked immunosorbent assay (cELISA) and enzyme-linked immunoassay (ELISA). Sera that gave a positive result were further investigated by western blot (WB) analysis to verify the presence of antibodies. Antibodies to N. caninum were detected in one of seven moose. The antibody titer was confirmed by NAT (1 : 1 280), cELISA (I = 91%) and ELISA (OD = 0.736). The main immunodominant antigens detected by WB were 120, 70, 55, 35 and 16 kDa proteins. This is the first evidence of N. caninum seropositivity in moose living in a natural environment in Europe.

  19. Population genetic structure of moose (Alces Alces) of South-central Alaska.

    USGS Publications Warehouse

    Wilson, Robert E.; McDonough, John T.; Barboza, Perry S.; Talbot, Sandra L.; Farley, Sean D.

    2015-01-01

    The location of a population can influence its genetic structure and diversity by impacting the degree of isolation and connectivity to other populations. Populations at range margins areoften thought to have less genetic variation and increased genetic structure, and a reduction in genetic diversity can have negative impacts on the health of a population. We explored the genetic diversity and connectivity between 3 peripheral populations of moose (Alces alces) with differing potential for connectivity to other areas within interior Alaska. Populations on the Kenai Peninsula and from the Anchorage region were found to be significantly differentiated (FST= 0.071, P < 0.0001) with lower levels of genetic diversity observed within the Kenai population. Bayesian analyses employing assignment methodologies uncovered little evidence of contemporary gene flow between Anchorage and Kenai, suggesting regional isolation. Although gene flow outside the peninsula is restricted, high levels of gene flow were detected within the Kenai that is explained by male-biased dispersal. Furthermore, gene flow estimates differed across time scales on the Kenai Peninsula which may have been influenced by demographic fluctuations correlated, at least in part, with habitat change.

  20. A geographic cluster of malignant catarrhal fever in moose (Alces alces) in Norway.

    PubMed

    Vikøren, Turid; Klevar, Siv; Li, Hong; Hauge, Anna Germundsson

    2015-04-01

    Three cases of lethal sheep-associated malignant catarrhal fever (SA-MCF) in free-ranging moose (Alces alces) were diagnosed in Lesja, Norway, December 2008-February 2010. The diagnosis was based on PCR identification of ovine herpesvirus 2 (OvHV-2) DNA (n = 3) and typical histopathologic lesions (n = 1). To study the possibility of subclinical or latent MCF virus (MCFV) infection in this moose population and in red deer (Cervus elaphus), we examined clinically normal animals sampled during hunting in Lesja 2010 by serology and PCR. Sera from 63 moose and 33 red deer were tested for antibodies against MCFV by competitive-inhibition enzyme-linked immunosorbent assay. To test for MCFVs, a consensus PCR for herpesviral DNA was run on spleen samples from 23 moose and 17 red deer. All samples were antibody and PCR negative. Thus, there is no evidence of previous exposure, subclinical infection, or latent infection in this sample. This seasonal cluster of SA-MCF cases (2008-10) may be attributable to exposure of moose to lambs when OvHV-2 shedding is presumed to be maximal, compounded by an unusual extended grazing period by sheep in the autumn.

  1. GEOGRAPHIC DISTRIBUTION AND MOLECULAR DIVERSITY OF BARTONELLA SPP. INFECTIONS IN MOOSE (ALCES ALCES) IN FINLAND.

    PubMed

    Pérez Vera, Cristina; Aaltonen, Kirsi; Spillmann, Thomas; Vapalahti, Olli; Sironen, Tarja

    2016-04-28

    Moose, Alces alces (Artiodactyla: Cervidae) in Finland are heavily infested with deer keds, Lipoptena cervi (Diptera: Hippoboschidae). The deer ked, which carries species of the genus Bartonella, has been proposed as a vector for the transmission of bartonellae to animals and humans. Previously, bartonella DNA was found in deer keds as well as in moose blood collected in Finland. We investigated the prevalence and molecular diversity of Bartonella spp. infection from blood samples collected from free-ranging moose. Given that the deer ked is not present in northernmost Finland, we also investigated whether there were geographic differences in the prevalence of bartonella infection in moose. The overall prevalence of bartonella infection was 72.9% (108/148). Geographically, the prevalence was highest in the south (90.6%) and lowest in the north (55.9%). At least two species of bartonellae were identified by multilocus sequence analysis. Based on logistic regression analysis, there was no significant association between bartonella infection and either age or sex; however, moose from outside the deer ked zone were significantly less likely to be infected (P<0.015) than were moose hunted within the deer ked zone.

  2. Gastrointestinal nematodes of moose (Alces alces) in relation to supplementary feeding.

    PubMed

    Milner, Jos M; Wedul, Sari J; Laaksonen, Sauli; Oksanen, Antti

    2013-01-01

    Winter supplementary feeding of wildlife is controversial because it may promote parasite and disease transmission by host aggregation. We investigated the effect of winter supplemental feeding of Scandinavian moose (Alces alces) on gastrointestinal (GI) parasite infection in two counties of southern Norway by comparing fecal egg counts of moose using, and not using, feeding stations between January 2007 and March 2010. We identified three different GI nematodes based on egg morphology. All three were found in Hedmark county while in Telemark county we found only Trichuris sp. (prevalence 33%). Prevalence of Trichostrongylidae (65%) and Nematodirus sp. (26%) in Hedmark was not affected by feeding station use. However, the probability of infection varied significantly between years sampled (Trichostrongylidae) and age class (Nematodirus sp.). Fecal egg counts (FEC), a proxy for intensity of infection, of Trichostrongylidae were higher in the year when winter weather conditions were more challenging and prevalence was higher, and decreased with increasing body mass. Adult moose had higher FECs than did juvenile moose, and female juveniles had lower abundances than did male juveniles. Use of feeding stations did not affect probability of infection with any of the nematodes or intensity of infection with Trichostrongylidae. We discuss our findings in terms of parasite life histories and recommend that parasitologic surveillance be included in the monitoring of feeding programs.

  3. Effects of simulated moose Alces alces browsing on the morphology of rowan Sorbus aucuparia

    USGS Publications Warehouse

    Jager, N.R.D.; Pastor, J.

    2010-01-01

    In much of northern Sweden moose Alces alces browse rowan Sorbus aucuparia heavily and commonly revisit previously browsed plants. Repeated browsing of rowan by moose has created some concern for its long-term survival in heavily browsed areas. We therefore measured how four years of simulated moose browsing at four population densities (0, 10, 30 and 50 moose/1,000 ha) changed plant height, crown width, available bite mass, the number of bites per plant and per plant forage biomass of rowan saplings. Increased biomass removal led to a significant decline in plant height (P < 0.001), but a significant increase in the number of bites per plant (P = 0.012). Increases in the number of bites per plant more than compensated for weak decreases in bite mass, leading to a weak increase in per plant forage biomass (P = 0.072). With the decline in plant height and increase in the number of stems per plant, a greater number of bites remain within the height reach of moose relative to unbrowsed controls. Moose therefore stand to benefit from revisiting previously browsed plants, which may result in feeding loops between moose and previously browsed rowan saplings. ?? 2010 Wildlife Biology, NKV.

  4. Short-term digestible energy intake in captive moose (Alces alces) on different diets.

    PubMed

    Clauss, Marcus; Kohlschein, Gina-Marie; Peemöller, Andreas; Hummel, Jürgen; Hatt, Jean-Michel

    2013-01-01

    Moose (Alces alces) are regularly described as problematic animals in captivity, mainly because of their particular digestive physiology and resulting feeding demands. According to the literature, moose regularly reject non-browse forages offered in captivity, which may indirectly lead to an overproportional ingestion of easily digestible feeds and thus chronic acidosis, which may in turn be the cause of their low life expectancy in captivity. By feeding experiments in four animals, this study aimed at testing whether maintaining moose on roughage-only diets appears feasible. The diets used consisted of the typical zoo ration with mixed feeds (including alfalfa hay), and exclusive diets of alfalfa hay, combinations of alfalfa hay and grass hay, alfalfa hay and grass hay and dried browse leaves, and dried browse leaves only. Whereas results confirmed that moose do not ingest grass hay in relevant amounts, digestible energy (DE) intake on alfalfa hay was, at 0.67 ± 0.15 DE MJ kg(-0.75) day(-1), above the estimated maintenance requirement of 0.6, and higher on the browse diets. At least for short-time periods, results contradict previous reports in the literature that alfalfa hay only is not a suitable maintenance diet for moose. At the same time the results promote feeding moose in captivity forage-based diets.

  5. Bartonella infections in deer keds (Lipoptena cervi) and moose (Alces alces) in Norway.

    PubMed

    Duodu, Samuel; Madslien, Knut; Hjelm, Eva; Molin, Ylva; Paziewska-Harris, Anna; Harris, Philip D; Colquhoun, Duncan J; Ytrehus, Bjørnar

    2013-01-01

    Infections with Bartonella spp. have been recognized as emerging zoonotic diseases in humans. Large knowledge gaps exist, however, relating to reservoirs, vectors, and transmission of these bacteria. We describe identification by culture, PCR, and housekeeping gene sequencing of Bartonella spp. in fed, wingless deer keds (Lipoptena cervi), deer ked pupae, and blood samples collected from moose, Alces alces, sampled within the deer ked distribution range in Norway. Direct sequencing from moose blood sampled in a deer ked-free area also indicated Bartonella infection but at a much lower prevalence. The sequencing data suggested the presence of mixed infections involving two species of Bartonella within the deer ked range, while moose outside the range appeared to be infected with a single species. Bartonella were not detected or cultured from unfed winged deer keds. The results may indicate that long-term bacteremia in the moose represents a reservoir of infection and that L. cervi acts as a vector for the spread of infection of Bartonella spp. Further research is needed to evaluate the role of L. cervi in the transmission of Bartonella to animals and humans and the possible pathogenicity of these bacteria for humans and animals.

  6. Sheep-associated malignant catarrhal fever in free-ranging moose (Alces alces) in Saskatchewan, Canada.

    PubMed

    Neimanis, Aleksija S; Hill, Janet E; Jardine, Claire M; Bollinger, Trent K

    2009-01-01

    Malignant catarrhal fever (MCF) is a sporadic disease of artiodactyls caused by several viruses in the Gammaherpesvirinae. We report two cases of MCF in free-living moose (Alces alces) from Saskatchewan. One was a thin, dehydrated, adult male found recumbent in 2006. At necropsy, ulcers were found in the intestine, bladder, and corneas. Microscopically, there was lymphocytic vasculitis and perivasculitis in many organs with infrequent fibrinoid necrosis. Ovine herpes virus-2 (OHV-2) was identified by polymerase chain reaction. A segment of the herpesviral DNA polymerase gene was 99% identical to published OHV-2 sequences. During a retrospective search of earlier cases, a female moose with lymphoplasmacytic meningoencephalitis examined in 2003 was identified and OHV-2 was amplified from paraffin-embedded tissues from this animal. We believe this to be the first description of MCF in free-ranging moose in North America. Infection requires contact with infected sheep or goats, and MCF in moose may become more prevalent as moose distribution continues to expand into agricultural prairie.

  7. Hair-loss epizootic in moose (Alces alces) associated with massive deer ked (Lipoptena cervi) infestation.

    PubMed

    Madslien, Knut; Ytrehus, Bjørnar; Vikøren, Turid; Malmsten, Jonas; Isaksen, Ketil; Hygen, Hans Olav; Solberg, Erling J

    2011-10-01

    Deer keds (Lipoptena cervi) are blood-sucking flies in the family Hippoboscidae; moose (Alces alces) are their main host in Scandinavia. There are no detailed reports of the negative impacts of deer keds on moose. In 2006 and 2007, hunters in southeastern Norway and midwestern Sweden found several moose cadavers with severe alopecia; numerous moose had extensive hair loss. Between February 2006 and June 2007, materials from 23 moose were submitted for laboratory examination and large numbers of deer keds were found in the coat of most animals. The body condition of the moose varied but was poor in animals with severe alopecia. The findings of enormous numbers of deer keds in the coat of the majority of the affected animals and a consistent histologic image (acute to chronic, multifocal to coalescing, eosinophilic to lymphocytic dermatitis), concurrent with the absence of any other lesions, trace element deficiencies, or dermal infections which are known to cause alopecia, suggest that the hair-loss epizootic was linked to massive infestations with deer keds. The emergence of this hair-loss syndrome implies that the dynamics between parasite and host have been disrupted by a currently unknown environmental or ecological factor. A high moose density, combined with extraordinarily mild weather June 2006-June 2007 and a particularly long period with the absence of night-frost in autumn of 2006, may have been ideal for deer ked development, survival, and optimal host acquisition.

  8. The first detection of species of Babesia Starcovici, 1893 in moose, Alces alces (Linnaeus), in Norway.

    PubMed

    Puraite, Irma; Rosef, Olav; Radzijevskaja, Jana; Lipatova, Indre; Paulauskas, Algimantas

    2016-04-01

    Babesiosis is an emerging zoonotic disease and various wildlife species are reservoir hosts for zoonotic species of Babesia Starcovici, 1893. The objective of the present study was to investigate the presence and prevalence of Babesia spp. in moose Alces alces (Linnaeus) in two regions of Norway. A total of 99 spleen samples were collected from animals of various ages from an area with the occurrence of the tick Ixodes ricinus (Linnaeus, 1758), and from an area where the ticks are known to be absent. Infection was detected by the amplification of different regions of the 18S rRNA gene by using two different PCR primer sets specific of Babesia. Babesia spp. were found in the spleen samples of four moose. All Babesia-infected animals were from an area where ticks occur, with an infection rate of 6% (4 of 70). Babesia-positive samples were obtained from a five-month old moose calf and three adults. Two Babesia species, Babesia capreoli (Enigk et Friedhoff, 1962) and a B. odocoilei-like, were identified. Co-infection with Anaplasma phagocytophilum was obtained in two animals. This is the first report of the occurrence of B. capreoli and B. odocoilei-like species in moose.

  9. Insight into the bacterial gut microbiome of the North American moose (Alces alces)

    PubMed Central

    2012-01-01

    Background The work presented here provides the first intensive insight into the bacterial populations in the digestive tract of the North American moose (Alces alces). Eight free-range moose on natural pasture were sampled, producing eight rumen samples and six colon samples. Second generation (G2) PhyloChips were used to determine the presence of hundreds of operational taxonomic units (OTUs), representing multiple closely related species/strains (>97% identity), found in the rumen and colon of the moose. Results A total of 789 unique OTUs were used for analysis, which passed the fluorescence and the positive fraction thresholds. There were 73 OTUs, representing 21 bacterial families, which were found exclusively in the rumen samples: Lachnospiraceae, Prevotellaceae and several unclassified families, whereas there were 71 OTUs, representing 22 bacterial families, which were found exclusively in the colon samples: Clostridiaceae, Enterobacteriaceae and several unclassified families. Overall, there were 164 OTUs that were found in 100% of the samples. The Firmicutes were the most dominant bacteria phylum in both the rumen and the colon. Microarray data available at ArrayExpress, accession number E-MEXP-3721. Conclusions Using PhyloTrac and UniFrac computer software, samples clustered into two distinct groups: rumen and colon, confirming that the rumen and colon are distinct environments. There was an apparent correlation of age to cluster, which will be validated by a larger sample size in future studies, but there were no detectable trends based upon gender. PMID:22992344

  10. A genetic discontinuity in moose (Alces alces) in Alaska corresponds with fenced transportation infrastructure

    USGS Publications Warehouse

    Wilson, Robert E.; Farley, Sean D.; McDonough, Thomas J.; Talbot, Sandra L.; Barboza, Perry S.

    2015-01-01

    The strength and arrangement of movement barriers can impact the connectivity among habitat patches. Anthropogenic barriers (e.g. roads) are a source of habitat fragmentation that can disrupt these resource networks and can have an influence on the spatial genetic structure of populations. Using microsatellite data, we evaluated whether observed genetic structure of moose (Alces alces) populations were associated with human activities (e.g. roads) in the urban habitat of Anchorage and rural habitat on the Kenai Peninsula, Alaska. We found evidence of a recent genetic subdivision among moose in Anchorage that corresponds to a major highway and associated infrastructure. This subdivision is most likely due to restrictions in gene flow due to alterations to the highway (e.g. moose-resistant fencing with one-way gates) and a significant increase in traffic volume over the past 30 years; genetic subdivision was not detected on the Kenai Peninsula in an area not bisected by a major highway. This study illustrates that anthropogenic barriers can substructure wildlife populations within a few generations and highlights the value of genetic assessments to determine the effects on connectivity among habitat patches in conjunction with behavioral and ecological data..

  11. The red fox (Vulpes vulpes) and the arctic fox (Vulpes lagopus) are definitive hosts of Sarcocystis alces and Sarcocystis hjorti from moose (Alces alces).

    PubMed

    Dahlgren, Stina S; Gjerde, Bjørn

    2010-09-01

    The aim of this study was to determine whether foxes might act as definitive hosts of Sarcocystis alces in moose. In 2 experiments, 6 silver foxes (Vulpes vulpes) and 6 blue foxes (Vulpes lagopus) were fed muscle tissue from moose containing numerous sarcocysts of S. alces, and euthanazed 7-28 days post-infection (p.i.). Intestinal mucosal scrapings and faecal samples were screened microscopically for Sarcocystis oocysts/sporocysts, which were identified to species by means of species-specific primers and sequence analysis targeting the ssu rRNA gene. All foxes in both experiments became infected with Sarcocystis; the oocysts were fully sporulated by 14 days p.i., containing sporocysts measuring 14-15 x 10 microm. Molecular identification revealed that the oocysts/sporocysts belonged to 2 species, S. alces and Sarcocystis hjorti, although sarcocysts of S. hjorti were only identified in moose subsequent to the infection of foxes. In the first experiment, all 8 foxes also became infected with a Hammondia sp. derived from moose, shedding unsporulated, subspherical oocysts, measuring 10-12 microm in diameter, from 6-7 days p.i. onwards. The study proved that canids (the red fox and arctic fox) are definitive hosts for S. alces and S. hjorti, as had been inferred from the phylogenetic position of these species.

  12. The Nutritional Balancing Act of a Large Herbivore: An Experiment with Captive Moose (Alces alces L)

    PubMed Central

    Felton, Annika M.; Felton, Adam; Raubenheimer, David; Simpson, Stephen J.; Krizsan, Sophie J.; Hedwall, Per-Ola; Stolter, Caroline

    2016-01-01

    The nutrient balancing hypothesis proposes that, when sufficient food is available, the primary goal of animal diet selection is to obtain a nutritionally balanced diet. This hypothesis can be tested using the Geometric Framework for nutrition (GF). The GF enables researchers to study patterns of nutrient intake (e.g. macronutrients; protein, carbohydrates, fat), interactions between the different nutrients, and how an animal resolves the potential conflict between over-eating one or more nutrients and under-eating others during periods of dietary imbalance. Using the moose (Alces alces L.), a model species in the development of herbivore foraging theory, we conducted a feeding experiment guided by the GF, combining continuous observations of six captive moose with analysis of the macronutritional composition of foods. We identified the moose’s self-selected macronutrient target by allowing them to compose a diet by mixing two nutritionally complementary pellet types plus limited access to Salix browse. Such periods of free choice were intermixed with periods when they were restricted to one of the two pellet types plus Salix browse. Our observations of food intake by moose given free choice lend support to the nutrient balancing hypothesis, as the moose combined the foods in specific proportions that provided a particular ratio and amount of macronutrients. When restricted to either of two diets comprising a single pellet type, the moose i) maintained a relatively stable intake of non-protein energy while allowing protein intakes to vary with food composition, and ii) increased their intake of the food item that most closely resembled the self-selected macronutrient intake from the free choice periods, namely Salix browse. We place our results in the context of the nutritional strategy of the moose, ruminant physiology and the categorization of food quality. PMID:26986618

  13. The Nutritional Balancing Act of a Large Herbivore: An Experiment with Captive Moose (Alces alces L).

    PubMed

    Felton, Annika M; Felton, Adam; Raubenheimer, David; Simpson, Stephen J; Krizsan, Sophie J; Hedwall, Per-Ola; Stolter, Caroline

    2016-01-01

    The nutrient balancing hypothesis proposes that, when sufficient food is available, the primary goal of animal diet selection is to obtain a nutritionally balanced diet. This hypothesis can be tested using the Geometric Framework for nutrition (GF). The GF enables researchers to study patterns of nutrient intake (e.g. macronutrients; protein, carbohydrates, fat), interactions between the different nutrients, and how an animal resolves the potential conflict between over-eating one or more nutrients and under-eating others during periods of dietary imbalance. Using the moose (Alces alces L.), a model species in the development of herbivore foraging theory, we conducted a feeding experiment guided by the GF, combining continuous observations of six captive moose with analysis of the macronutritional composition of foods. We identified the moose's self-selected macronutrient target by allowing them to compose a diet by mixing two nutritionally complementary pellet types plus limited access to Salix browse. Such periods of free choice were intermixed with periods when they were restricted to one of the two pellet types plus Salix browse. Our observations of food intake by moose given free choice lend support to the nutrient balancing hypothesis, as the moose combined the foods in specific proportions that provided a particular ratio and amount of macronutrients. When restricted to either of two diets comprising a single pellet type, the moose i) maintained a relatively stable intake of non-protein energy while allowing protein intakes to vary with food composition, and ii) increased their intake of the food item that most closely resembled the self-selected macronutrient intake from the free choice periods, namely Salix browse. We place our results in the context of the nutritional strategy of the moose, ruminant physiology and the categorization of food quality.

  14. Parasitism of the deer ked, Lipoptena cervi, on the moose, Alces alces, in eastern Finland.

    PubMed

    Paakkonen, T; Mustonen, A-M; Roininen, H; Niemelä, P; Ruusila, V; Nieminen, P

    2010-12-01

    The deer ked, Lipoptena cervi L. (Diptera: Hippoboscidae), is an ectoparasitic fly that spread to Finland in the early 1960s from the southeast across the Soviet border. It is currently a common parasite of the moose, Alces alces (Artiodactyla: Cervidae), in the southern part of the country and its area of distribution is gradually spreading to Finnish Lapland, where it will come into contact with another potential cervid host, the semi-domesticated reindeer, Rangifer tarandus tarandus. The aim of this study was to determine the intensity of deer ked parasitism on the moose in eastern Finland. Whole skins of 23 moose were examined for the presence of deer keds, which were extracted and their total numbers estimated. The intensity of deer ked parasitism was correlated to the age, sex, skin area and anatomical region of the host. Bulls had the highest total number of keds (10616 ± 1375) and the highest deer ked density (35.7 ± 4.4 keds/dm(2) of skin). Cows had a higher total number of keds than calves (3549 ± 587 vs. 1730 ± 191), but ked densities on cows and calves were roughly equal (11.8 ± 1.7 vs. 9.4 ± 1.1 keds/dm(2) of skin). The density of keds was highest on the anterior back, followed by the posterior back, front limbs, abdomen, head and hind limbs. The sex ratio of deer keds was close to equal (male : female, 1.0 : 1.1). After they had consumed blood, male keds were heavier than females. As the total numbers and densities of deer keds were higher than reported previously on moose or for any other louse fly species, the effects of parasitism on the health of the host species should be determined.

  15. Reproductive failure in moose (Alces alces) due to embryonic mortality and unfertilized oocytes.

    PubMed

    Malmsten, Jonas; Dalin, Anne-Marie

    2014-01-01

    Knowledge on reproductive success is vital for successful management of large ungulates and is often measured by means of observing surviving offspring. In harvested ungulates, postmortem investigations of reproductive organs are used to estimate reproductive potential by obtaining ovulation rates and fetus numbers. However, there are differences in numbers of offspring observed, fetal/embryo counts, and ovulation rates. We hypothesize that the discrepancy between estimated reproductive potential and reproductive outcome in large ungulates is not only due to ova loss but also due to embryonic mortality. We investigated reproductive status in early pregnancy by sampling hunter-harvested moose (Alces alces) in southern Sweden from 2007 to 2011. In all, 213 reproductive organs were examined postmortem, and in confirmed pregnant moose (n = 53), 25 % (19 of 76) embryos were nonviable and 6 % of ova was unfertilized. The discrepancy between the ovulation rate of all pregnant moose (1.49) and the number of expected offspring per pregnant female, when embryonic mortality and unfertilized oocytes were accounted for (1.08), was 27.5 %. An association between inflammation of the inner mucous membrane (endometritis) of the moose's uterus and embryonic mortality was observed. This is the first comprehensive report of embryonic mortality and endometritis in moose. The observed discrepancy between ovulation rates and early embryonic development/survival shows that ovulation rates are indicative but not accurate estimates of moose reproductive rate. The use of ovulation rates as a sole estimator of future offspring rates may lead to an overharvest of a managed moose population.

  16. Mitochondrial phylogeography of moose (Alces alces): Late Pleistocene divergence and population expansion

    USGS Publications Warehouse

    Hundertmark, Kris J.; Shields, Gerald F.; Udina, Irina G.; Bowyer, R. Terry; Danilkin, Alexei A.; Schwartz, Charles C.

    2002-01-01

    We examined phylogeographic relationships of moose (Alces alces) worldwide to test the proposed existence of two geographic races and to infer the timing and extent of demographic processes underpinning the expansion of this species across the Northern Hemisphere in the late Pleistocene. Sequence variation within the left hypervariable domain of the control region occurred at low or moderate levels worldwide and was structured geographically. Partitioning of genetic variance among regions indicated that isolation by distance was the primary agent for differentiation of moose populations but does not support the existence of distinct eastern and western races. Levels of genetic variation and structure of phylogenetic trees identify Asia as the origin of all extant mitochondrial lineages. A recent coalescence is indicated, with the most recent common ancestor dating to the last ice age. Moose have undergone two episodes of population expansion, likely corresponding to the final interstade of the most recent ice age and the onset of the current interglacial. Timing of expansion for the population in the Yakutia–Manchuria region of eastern Asia indicates that it is one of the oldest populations of moose and may represent the source of founders of extant populations in North America, which were colonized within the last 15,000 years. Our data suggest an extended period of low population size or a severe bottleneck prior to the divergence and expansion of extant lineages and a recent, less-severe bottleneck among European lineages. Climate change during the last ice age, acting through contraction and expansion of moose habitat and the flooding of the Bering land bridge, undoubtedly was a key factor influencing the divergence and expansion of moose populations.

  17. Antler stiffness in moose (Alces alces): correlated evolution of bone function and material properties?

    PubMed

    Blob, Richard W; Snelgrove, Jason M

    2006-09-01

    The material properties of bone can vary considerably among skeletal elements from different parts of the body that serve different functions. However, functional demands placed on a specific type of skeletal element also can vary at a variety of scales, such as between different parts of the element, among individuals of a species, and across species. Variation in bone material properties might be correlated with differing functional demands at any of these scales. In this study we performed three-point bending tests on bone specimens extracted from antlers of moose (Alces alces) to test for three types of variation in bone material stiffness (Young's modulus): within the antler structure, between populations of moose, and between moose and other deer species. Because superficial portions of the antler are exposed to greater bending stress and strain than deeper portions, and because the antler beam (the basal shaft that attaches to the skull) is subjected to greater bending moments than more distal parts of the antler, we predicted that superficial bone and bone from the beam would be stiffer than bone from other parts of the antler. Instead, we identified no significant differences in these comparisons. There were also no significant differences in antler stiffness between moose from Michigan and the Yukon, even though the rapid growth required of antlers from northern latitudes like the Yukon has the potential to compromise bone material properties. However, moose have significantly stiffer antlers (11.6 +/- 0.45 GPa, mean +/- SE) than any other deer in the odocoileine lineage. Moreover, phylogenetic reconstructions of the evolution of antler stiffness in deer indicate a strong potential that high antler stiffness is a derived feature of moose. The unusual palmate shape of moose antlers likely subjects their antler beams to higher bending moments than found in other odocoileines, a factor that may have contributed to the evolutionary divergence of moose antler

  18. Winter body condition of moose (Alces alces) in a declining population in northeastern Minnesota.

    PubMed

    DelGiudice, Glenn D; Sampson, Barry A; Lenarz, Mark S; Schrage, Michael W; Edwards, Andrew J

    2011-01-01

    Assessments of the condition of moose (Alces alces) may be particularly informative to understanding the dynamics of populations and other influential factors. During February-March 2003 to 2005, we assessed the nutritional condition of 79 moose (39 females, 40 males) in northeastern Minnesota by body condition scoring (BCS(F), scale of 0-10); 67 of these by were assessed by ultrasonographic measurements of rump fat (Maxfat), which was used to estimate ingesta-free body fat (IFBF) in all but two of the females. Scores of the BCS(F) were related (r(2)=0.34, P<0.0001) to Maxfat. Body condition scores were not affected by sex × capture-year, capture-year, or age-at-capture, but the mean body condition score of males (6.5 ± 0.2 [SE], n=40) was less (P ≤ 0.009) than that of females (7.4 ± 0.2, n=39). Overall, Maxfat ranged from 0.0 to 4.6 and 0.3 to 2.8 cm in females and males, respectively, and was unaffected by age-at-capture. There was a sex×capture-year effect (P=0.021) on Maxfat; mean values were stable for males during the winters of 2003 to 2005 but in females were lowest during 2003, consistent with the lowest pregnancy rates and lowest winter and spring survival compared to 2004 and 2005. Based on estimates of percent IFBF, late winter-early spring survival in 2003 of at least 11% of the collared animals assessed by Maxfat, 21% of the adult females, specifically, may have been seriously challenged directly by poor condition. Data from this study provide reference values and assessments of body condition of moose that will be an essential component of the additional, comprehensive research needed to better understand the influence of extrinsic and intrinsic factors on the performance of this viable, but declining, population. For future research, we will concentrate on developing a more-reliable BCS which would allow IFBF estimation once rump fat is depleted.

  19. Age structure of moose (Alces alces) killed by gray wolves (Canis lupus) in northeastern Minnesota, 1967-2011

    USGS Publications Warehouse

    Mech, L. David; Nelson, Michael E.

    2013-01-01

    The age structure of Moose (Alces alces) killed by gray Wolves (Canis lupus) is available from only two national parks in the united States where hunting by people is not allowed and from three areas in Alaska where Moose are hunted (Mech 1966; Peterson et al.1984; Ballard et al. 1987; Mech et al. 1998). The samples of Moose killed by gray Wolves from each hunted area are relatively small (47–117), given that Moose live to 20 or more years (Passmore et al. 1955). This article adds age data from another 77 Moose killed by gray Wolves from a fourth (lightly) human-hunted area and assesses the age structure of all the samples.

  20. Morphological and molecular characteristics of four Sarcocystis spp. in Canadian moose (Alces alces), including Sarcocystis taeniata n. sp.

    PubMed

    Gjerde, Bjørn

    2014-04-01

    Individual sarcocysts were isolated from fresh or alcohol-fixed muscle samples of two moose from Alberta, Canada, and examined by light (LM) and scanning electron microscopy (SEM) and molecular methods, comprising polymerase chain reaction (PCR) amplification and sequencing of the complete18S rRNA gene and the partial cytochrome c oxidase subunit I gene (cox1). By LM, four sarcocyst types were recognized, and the sequencing results showed that each type represented a distinct species, i.e. Sarcocystis alces, Sarcocystis alceslatrans, Sarcocystis ovalis and Sarcocystis taeniata n. sp. The finding of S. alceslatrans and S. ovalis has been reported briefly previously, but further details are provided here, including the ultrastructure of sarcoysts of S. alceslatrans as seen by SEM. The species S. alces was found for the first time in Canadian moose, whereas the finding of S. taeniata is the first record of this species in any host. The sarcocysts of S. taeniata were sac-like and about 1,000-1,100 × 60-80 μm in size. By LM, the cysts had a thin and smooth wall with no visible protrusions, whereas SEM revealed that the cyst surface had sparsely but regularly distributed, thin ribbon-like protrusions, about 2 μm long and 0.2 μm wide, lying flat against the surface and leaving most of the cyst surface naked. Similar protrusions have previously been reported from Sarcocystis grueneri in reindeer, which was found by sequence comparisons and phylogenetic analyses to be the species most closely related to S. taeniata. The phylogenetic analyses further suggested that S. taeniata, like S. alces and S. alceslatrans, use canids as definitive hosts, whereas corvid birds are known definitive hosts for S. ovalis. In contrast to the three other species found, S. taeniata displayed considerable intra-specific and intra-isolate sequence variation (substitutions, insertions/deletions) in certain regions of the 18S rRNA gene.

  1. 20 CFR 655.132 - H-2A labor contractor (H-2ALC) filing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Application for Temporary Employment Certification the following: (1) The name and location of each fixed-site... employment in which the fixed-site employer(s) to whom an H-2ALC is furnishing employees will be utilizing... dates when the H-2ALC will be providing the workers to each fixed site, and a description of the...

  2. Control of interfaces in Al-C fibre composites

    NASA Technical Reports Server (NTRS)

    Warrier, S. G.; Blue, C. A.; Lin, R. Y.

    1993-01-01

    The interface of Al-C fiber composite was modified by coating a silver layer on the surface of carbon fibres prior to making composites, in an attempt to improve the wettability between molten aluminum and carbon fibers during infiltration. An electroless plating technique was adopted and perfected to provide a homogeneous silver coating on the carbon fiber surface. Al-C fiber composites were prepared using a liquid infiltration technique in a vacuum. It was found that silver coating promoted the wetting between aluminum and carbon fibers, particularly with polyacrylonitrile-base carbon fibers. However, due to rapid dissolution of silver in molten aluminum, it was believed that the improved infiltration was not due to the wetting behavior between molten aluminum and silver. The cleaning of the fiber surface and the preservation of the cleaned carbon surface with silver coating was considered to be the prime reason for the improved wettability. Interfacial reactions between aluminum and carbon fibers were observed. Amorphous carbon was found to react more with aluminum than graphitic carbon. This is believed to be because of the inertness of the graphitic basal planes.

  3. Analysis of the alcABC operon encoding alcaligin biosynthesis enzymes in Bordetella bronchiseptica.

    PubMed

    Giardina, P C; Foster, L A; Toth, S I; Roe, B A; Dyer, D W

    1997-07-18

    We previously cloned a B. bronchiseptica (Bb) genomic DNA fragment that complements a Bb alcaligin biosynthesis mutant, and reported the identification of a gene, alcA, with predicted protein sequence similarity to siderophore biosynthesis enzymes from other organisms. In the present study we show that further nt sequencing of this region revealed two open reading frames (ORFs) 3' to alcA that encode putative proteins AlcB and AlcC, with significant sequence similarity to the aerobactin biosynthesis enzymes IucB and IucC, respectively. RT-PCR analysis indicated that the three ORFs are encoded on a single transcript, and that this operon is repressed at the transcriptional level by Fe. Primer extension analysis placed the transcriptional start point (tsp) 35 nt from the 5' end of the Fur consensus sequence and 188 nt from the putative start of translation of AlcA.

  4. Changes in ripening-related processes in tomato conditioned by the alc mutant.

    PubMed

    Mutschler, M; Guttieri, M; Kinzer, S; Grierson, D; Tucker, G

    1988-08-01

    The alc mutation affects the ripening and storability of tomato fruit. The alteration of fruit color in alc lines is due to a reduction in total pigment and a reduction in lycopene relative to total carotinoids. Polygalacturonase (PG) activity is reduced to less than 5% of normal, and the isozymes PG2a and PG2b are absent in alc fruit. The level of anti-PG precipitable proteins is also reduced to less than 5% of normal. Total polyA + mRNA is not significantly reduced in ripening alc fruit, but hybridization of polyA + mRNA to different ripening-related cDNA clones showed that specific mRNAs are present at reduced levels in the mutant. Specific mRNA levels were reduced to 10%-80% of normal levels, depending on the cDNA clone used as the probe. PG mRNA was present at 5%-10% of the normal level.All effects of alc on fruit ripening are relived in the line Alcobaca-red, which arose spontaneously from the original alc line, Alcobaca. The Alcobaca-red trait segregates as a single dominant trait at or very near the alc locus, and it is probably the result of a reverse mutation at the alc locus.The chromosomal locations of regions homologous to 5 ripening-related cDNA probes were determined. Regions homologous to 4 of these probes map to chromosomes other than chromosome 10, indicating that the effects of alc are transactive. A cDNA clone for PG was homologous to only one chromosomal region. This region is located on chromosome 10, which is also the chromosome on which alc and nor are located.

  5. Physiological evaluation of free-ranging moose (Alces alces) immobilized with etorphine-xylazine-acepromazine in Northern Sweden

    PubMed Central

    2012-01-01

    Background Evaluation of physiology during capture and anesthesia of free-ranging wildlife is useful for determining the effect that capture methods have on both ecological research results and animal welfare. This study evaluates capture and anesthesia of moose (Alces alces) with etorphine-xylazine-acepromazine in Northern Sweden. Methods Fifteen adult moose aged 3–15 years were darted from a helicopter with a combination of 3.37 mg etorphine, 75 mg xylazine, and 15 mg acepromazine. Paired arterial blood samples were collected 15 minutes apart with the first sample at 15–23 minutes after darting and were analyzed immediately with an i-STAT®1 Portable Clinical Analyzer. Results All animals developed hypoxemia (PaO2 <10 kPa) with nine animals having marked hypoxemia (PaO2 5.5-8 kPa). All moose were acidemic (ph<7.35) with nine moose having marked acidemia (pH<7.20). For PaCO2, 14 moose had mild hypercapnia (PaCO2 6-8 kPa) and two had marked hypercapnia (PaCO2>8 kPa). Pulse, respiratory rate, pH and HCO3 increased significantly over time from darting whereas lactate decreased. Conclusions The hypoxemia found in this study is a strong indication for investigating alternative drug doses or combinations or treatment with supplemental oxygen. PMID:23276208

  6. Characteristics of spermatozoa and reproductive organs in relation to age and body weight in Swedish moose (Alces alces).

    PubMed

    Malmsten, Jonas; Söderquist, Lennart; Thulin, Carl-Gustaf; Dalin, Anne-Marie

    2015-02-01

    Knowledge of the reproductive biology of game species is vital for sustainable management. In moose (Alces alces), research in reproductive characteristics has focused on the female, whereas there are few studies in male moose. The aim of the present study was to investigate sperm morphology and chromatin integrity (SCSA), and their relationships with testicular and epididymal features, as well as temporal aspects with respect to the hunting season. In total, 143 male moose aged 1.5-11.5 years were sampled from 2008 to 2011. The proportion of normal spermatozoa (PNS) ranged from 1.5% to 82.0%, with a mean of 51%, and the %DFI (DNA fragmentation index) ranged from 2.5% to 36.7% (mean 9.5). PNS decreased temporally, and was positively associated with carcass and testes weight. Body weight and testes weight had positive effect on PNS regardless of age. No effect of any explanatory variables was observed on the DFI. The testis/body weight ratio of moose (0.033%) is among the lowest reported among mammals, indicating a less polygynous mating system than in roe deer and red deer. For reproduction success in moose, a high body weight in males is favorable, as is a balanced sex ratio. Thus, males should not be harvested prior to the time when the majority of females have passed their first oestrus of the season.

  7. The effects of an abundant ectoparasite, the deer ked (Lipoptena cervi), on the health of moose (Alces alces) in Finland.

    PubMed

    Paakkonen, Tommi; Mustonen, Anne-Mari; Käkelä, Reijo; Laaksonen, Sauli; Solismaa, Milla; Aho, Jari; Puukka, Katri; Nieminen, Petteri

    2012-09-01

    The deer ked (Lipoptena cervi, Diptera, Hippoboscidae) is a haematophagous parasitic fly of the moose (Alces alces) and other cervids, and it is very common in southern and central parts of Finland. The aim of this study was to determine how the intensive parasitism caused by the deer ked affects the health and welfare of the moose. Moose blood samples (n = 78) were collected from deer ked-infested and ked-free regions at 62-68° N and analysed for haematology and clinical chemistry. In addition, tissue samples of moose (n = 23) were collected from a deer ked-infested region at 62° N to determine how the parasite load correlates to several physiological variables of the host. The differences in the blood and plasma values between the deer ked-free and ked-infested animals were minor. In the infested regions, the moose had higher mean corpuscular haemoglobin concentrations unlikely to have been caused by the parasitism. The intensities of deer keds had no consistent correlations with the values of plasma clinical chemistry, endocrinology, amino acids, tissue enzyme activities or body energy stores. However, the hepatic percentages of several individual n-3 polyunsaturated fatty acids (PUFA) and the n-3 PUFA sum correlated inversely with the intensity and density of deer keds. Although a wide array of physiological variables was determined, only minor effects caused by the heavy deer ked parasitism could be detected, suggesting that the moose might tolerate this parasite relatively well.

  8. Absolute Lymphocyte Count (ALC) after Induction Treatment Predicts Survival of Pediatric Patients with Acute Lymphoblastic Leukemia.

    PubMed

    Farkas, Tamas; Müller, Judit; Erdelyi, Daniel J; Csoka, Monika; Kovacs, Gabor T

    2017-01-30

    Absolute Lymphocyte Count (ALC) has been recently established as a prognostic factor of survival in pediatric Acute Lymphoblastic Leukemia (ALL). A retrospective analysis of 132 patients treated according the BFM - ALLIC 2002 protocol was performed in a single institution. A possible association between ALC values and Overall Survival (OS) or Event-Free Survival (EFS) was evaluated at multiple time points during induction chemotherapy. ALC higher than 350 cells/μL measured on the 33th day of induction was associated with better Overall- and Event-Free Survival in both Kaplan-Meier (OS 88.6% vs. 40%; p < 0.001 / EFS 81.6% vs. 30%; p < 0.001) and Cox regression (OS HR 8.77 (3.31-23.28); p < 0.001) and EFS HR 6.61 (2.79-15.63); p < 0.001) analyses. There was no association between survival and measured ALC values from earlier time points (day of diagnosis, days 8 and 15) of induction therapy. Patients with low ALC values tend to have higher risk (MR or HR groups) and a higher age at diagnosis (>10 years). With help of day 33 ALC values of 350 cells/μL cutoff it was possible to refine day 33 flow cytometry (FC) Minimal Residual Disease (MRD) results within the negative cohort: higher ALC values were significantly associated with better survival. ALC on day 33 (350 cells/μL) remained prognostic for OS and EFS in multivariate analysis after adjusting it for age, cytogenetics, immunophenotype and FC MRD of induction day 33. According to these findings ALC on day 33 of induction is a strong predictor of survival in pediatric ALL.

  9. Prevalence of antibodies against Toxoplasma gondii and Neospora caninum in moose (Alces alces) and roe deer (Capreolus capreolus) in Sweden.

    PubMed

    Malmsten, Jonas; Jakubek, Eva-Britt; Björkman, Camilla

    2011-05-11

    Toxoplasma gondii and Neospora caninum are two coccidian parasites with a worldwide distribution. T. gondii is one of the more common parasitic zoonoses in the world and in young children and immunocompromised persons, infection can lead to severe disease and death. N. caninum is an important cause of abortions in cattle. Wildlife have been identified as reservoirs and transmitters for both parasites. The purpose of this study was to investigate the seroprevalences of T. gondii, and N. caninum in moose (Alces alces), and roe deer (Capreolus capreolus) in Sweden. Blood samples were collected from 417 moose during 2000-2005 and from 199 roe deer during 1990-2007. The samples were investigated for presence of antibodies by a T. gondii direct agglutination test and a N. caninum iscom ELISA. Because the iscom ELISA has not been validated for moose or roe deer, sera that gave a positive result were further investigated by immunoblot analysis to verify presence of antibodies. Antibodies to T. gondii were detected in 85 (20%) and 68 (34%) moose and roe deer sera, respectively. In moose the seroprevalence was higher in south and central Sweden than in the north, whereas there was no difference between the regions for roe deer. Adult moose and roe deer had higher odds of being seropositive than young animals but there were no difference in seroprevalence between males and females. One roe deer was positive by immunoblotting and was regarded as N. caninum positive, whereas all moose sera were negative. The results show that T. gondii infection is widely spread in the Swedish moose and roe deer populations. Precautions should therefore be taken when handling internal organs and carcasses of harvested cervids. Proper handling and cooking of game meat also is important to prevent toxoplasmosis in humans.

  10. High-throughput DNA sequencing of the ruminal bacteria from moose (Alces alces) in Vermont, Alaska, and Norway.

    PubMed

    Ishaq, Suzanne L; Wright, André-Denis

    2014-08-01

    In the present study, the rumen bacteria of moose (Alces alces) from three distinct geographic locations were investigated. Moose are large, browsing ruminants in the deer family, which subsist on fibrous, woody browse, and aquatic plants. Subspecies exist which are distinguished by differing body and antler size, and these are somewhat geographically isolated. Seventeen rumen samples were collected from moose in Vermont, Alaska, and Norway, and bacterial 16S ribosomal RNA genes were sequenced using Roche 454 pyrosequencing with titanium chemistry. Overall, 109,643 sequences were generated from the 17 individual samples, revealing 33,622 unique sequences. Members of the phylum Bacteroidetes were dominant in samples from Alaska and Norway, but representatives of the phylum Firmicutes were dominant in samples from Vermont. Within the phylum Bacteroidetes, Prevotellaceae was the dominant family in all three sample locations, most of which belonged to the genus Prevotella. Within the phylum Firmicutes, the family Lachnospiraceae was the most prevalent in all three sample locations. The data set supporting the results of this article is available in the Sequence Read Archive (SRA), available through NCBI [study accession number SRP022590]. Samples clustered by geographic location and by weight and were heterogenous based on gender, location, and weight class (p < 0.05). Location was a stronger factor in determining the core microbiome than either age or weight, but gender did not appear to be a strong factor. There were no shared operational taxonomic units across all 17 samples, which indicates that these moose may have been isolated long enough to preclude a core microbiome among moose. Other potential factors discussed include differences in climate, food quality and availability, gender, and life cycle.

  11. Structure of V{sub 2}AlC studied by theory and experiment

    SciTech Connect

    Schneider, Jochen M.; Mertens, Raphael; Music, Denis

    2006-01-01

    We have studied V{sub 2}AlC (space group P6{sub 3}/mmc, prototype Cr{sub 2}AlC) by ab initio calculations. The density of states (DOS) of V{sub 2}AlC for antiferromagnetic, ferromagnetic, and paramagnetic configurations have been discussed. According to the analysis of DOS and cohesive energy, no significant stability differences between spin-polarized and non-spin-polarized configurations were found. Based on the partial DOS analysis, V{sub 2}AlC can be classified as a strongly coupled nanolaminate according to our previous work [Z. Sun, D. Music, R. Ahuja, S. Li, and J. M. Schneider, Phys. Rev. B 70, 092102 (2004)]. Furthermore, this phase has been synthesized in the form of thin films by magnetron sputtering. The equilibrium volume, determined by x-ray diffraction, is in good agreement with the theoretical data, implying that ab initio calculations provide an accurate description of V{sub 2}AlC.

  12. Properties of Cr2AlC MAX phase thin films prepared by reactive magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Buck, Zachary; Donato, Tyler; Rotella, Christopher; Lunk, Carl; Lofland, S. E.; Hettinger, J. D.

    2012-02-01

    Mn+ 1AXn (MAX) phases, where n is 1, 2, and 3, M is an early transition metal, A is an A-group element, and X is either C or N, are ternary carbides with unique properties such as low density, easy machinability, and good oxidation resistance. The MAX phase Cr2AlC is of particular interest for industrial applications to its excellent high-temperature oxidation resistance and relatively low synthesis temperature. We prepared Cr2AlC thin films on c-axis oriented single crystal Al2O3, glassy carbon and Si thermal oxide substrates using reactive magnetron sputtering as precursor materials for carbide-derived carbon (CDC) films for ``on-chip'' supercapacitors. Film deposition was optimized using elemental composition data obtained by WDXRF. Optimized films were characterized using XRD and scanning electron microscopy. It was found that textured Cr2AlC films only form when the composition was Al-rich allowing the formation of a Cr5Al8 interfacial layer. As film composition was optimized, the interfacial layer did not form but the XRD peaks associated with the Cr2AlC also decreased in magnitude. Extremely high-textured films were grown when a thin buffer layer of CrAl2 was deposited on the substrate before depositing the Cr2AlC films. This result suggests that Cr2AlC films may not be ideal for CDC applications since the films may ``lift-off'' during conversion due to the existence of the naturally occurring buffer-layer.

  13. 40 CFR 721.10457 - 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol, fumaric acid and propylene glycol. 721.10457...-hexanol, fumaric acid and propylene glycol. (a) Chemical substance and significant new uses subject to... alc., cyclohexanol, 2-ethyl-1-hexanol, fumaric acid and propylene glycol (PMN P-03-154; CAS No....

  14. 40 CFR 721.10457 - 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol, fumaric acid and propylene glycol. 721.10457...-hexanol, fumaric acid and propylene glycol. (a) Chemical substance and significant new uses subject to... alc., cyclohexanol, 2-ethyl-1-hexanol, fumaric acid and propylene glycol (PMN P-03-154; CAS No....

  15. Short-Term Evaluation of a Web-Based College Alcohol Misuse and Harm Prevention Course (College Alc)

    ERIC Educational Resources Information Center

    Paschal, Mallie J.; Bersamin, Melina; Fearnow-Kenney, Melodie; Wyrick, David; Currey, David

    2006-01-01

    This study examined the short-term effects of a web-based alcohol misuse and harm prevention course (College Alc) among incoming freshmen at a California public university. Analysis results indicated that at the end of the fall semester, students randomly assigned to College Alc (n = 173) had a higher level of alcohol-related knowledge and less…

  16. Potential Vertical Transmission of Winter Ticks (Dermacentor albipictus) from Moose (Alces americanus) Dams to Neonates.

    PubMed

    Severud, William J; DelGiudice, Glenn D

    2016-01-01

    North American moose (Alces americanus) frequently become infested with winter ticks (Dermacentor albipictus). During capture of neonatal moose in northeastern Minnesota, US, in May-June 2013 and 2014, we recovered adult ticks from neonates, presumably vertically transferred from dams, heretofore, not documented. Infestations on neonates may have population-level implications.

  17. Synthesis, physical properties and band structure of non-magnetic Y3AlC

    NASA Astrophysics Data System (ADS)

    Ghule, S. S.; Garde, C. S.; Ramakrishnan, S.; Singh, S.; Rajarajan, A. K.; Laad, Meena

    2016-10-01

    Y3AlC has been synthesized by arc melting and subsequent annealing. Rietveld analysis of the powder x-ray diffraction (XRD) data confirms cubic Pm-3m structure. Electrical resistivity (ρ) of Y3AlC exhibits metallic behaviour. No sign of superconductivity is observed down to the lowest measurement temperatures of 4.2 K in ρ, and 2 K in magnetic susceptibility (χ) and specific heat (Cp) measurements. The value of the electronic specific heat coefficient γ is 1.36 mJ/K2 mol from which the density of states (DOS) at the Fermi energy (EF) is obtained as 0.57 states/eV.unit cell. The value of Debye temperature θD is estimated to be 315 K. Electronic band structure calculations of Y3AlC reveal a pseudo-gap in the DOS at EF leading to a small value of 0.5 states/eV unit cell which matches quite well with that obtained from γ. Non-zero value of the DOS indicates metallic behaviour as confirmed by our ρ data. Covalent and ionic bonding seem to co-exist with metallic bonding in Y3AlC as indicated by van Arkel- Ketelaar triangle for Zintl-like systems.

  18. Structural inheritance and difference between Ti2AlC, Ti3AlC2 and Ti5Al2C3 under pressure from first principles

    NASA Astrophysics Data System (ADS)

    Gao, Qing-He; Du, An; Yang, Ze-Jin

    2017-01-01

    The structural inheritance and difference between Ti2AlC, Ti3AlC2 and Ti5Al2C3 under pressure from first principles are studied. The results indicate that the lattice parameter a are almost the same within Ti2AlC, Ti3AlC2 and Ti5Al2C3, and the value of c in Ti5Al2C3 is the sum of Ti2AlC and Ti3AlC2 which is revealed by the covalently bonded chain in the electron density difference: Al-Ti-C-Ti-Al for Ti2AlC, Al-Ti2-C-Ti1-C-Ti2-Al for Ti3AlC2 and Al-Ti3-C2-Ti3-Al-Ti2-C1-Ti1-C1-Ti2-Al for Ti5Al2C3. The calculated axial compressibilities, volumetric shrinkage, elastic constant c11, c33/c11 ratio, bulk modulus, shear modulus, and Young’s modulus of Ti5Al2C3 are within the range of the end members (Ti2AlC and Ti3AlC2) in a wide pressure range of 0-100 GPa. Only Ti2AlC is isotropic crystal at about 50 GPa within the Ti-Al-C compounds. All of the Ti 3d density of states curves of the three compounds move from lower energy to higher energy level with pressure increasing. The similarities of respective bond length, bond overlap population (Ti-C, Ti-Al and Ti-Ti), atom Mulliken charges under pressure as well as the electron density difference for the three compounds are discovered. Among the Ti-Al-C ternary compounds, Ti-Ti bond behaves least compressibility, whereas the Ti-Al bond is softer than that of Ti-C bonds, which can also been confirmed by the density of states and electron density difference. Bond overlap populations of Ti-Ti, Ti-C and Ti-Al indicate that the ionicity interaction becomes more and more stronger in the three structures as the pressure increasing. Mulliken charges of Ti1, Ti2, Ti3, C and Al are 0.65, 0.42, 0.39, ‑0.73, ‑0.04 at 0 GPa, respectively, which are consistent with the Pauling scale.

  19. Alcadein cleavages by amyloid beta-precursor protein (APP) alpha- and gamma-secretases generate small peptides, p3-Alcs, indicating Alzheimer disease-related gamma-secretase dysfunction.

    PubMed

    Hata, Saori; Fujishige, Sayaka; Araki, Yoichi; Kato, Naoko; Araseki, Masahiko; Nishimura, Masaki; Hartmann, Dieter; Saftig, Paul; Fahrenholz, Falk; Taniguchi, Miyako; Urakami, Katsuya; Akatsu, Hiroyasu; Martins, Ralph N; Yamamoto, Kazuo; Maeda, Masahiro; Yamamoto, Tohru; Nakaya, Tadashi; Gandy, Sam; Suzuki, Toshiharu

    2009-12-25

    Alcadeins (Alcs) constitute a family of neuronal type I membrane proteins, designated Alc(alpha), Alc(beta), and Alc(gamma). The Alcs express in neurons dominantly and largely colocalize with the Alzheimer amyloid precursor protein (APP) in the brain. Alcs and APP show an identical function as a cargo receptor of kinesin-1. Moreover, proteolytic processing of Alc proteins appears highly similar to that of APP. We found that APP alpha-secretases ADAM 10 and ADAM 17 primarily cleave Alc proteins and trigger the subsequent secondary intramembranous cleavage of Alc C-terminal fragments by a presenilin-dependent gamma-secretase complex, thereby generating "APP p3-like" and non-aggregative Alc peptides (p3-Alcs). We determined the complete amino acid sequence of p3-Alc(alpha), p3-Alc(beta), and p3-Alc(gamma), whose major species comprise 35, 37, and 31 amino acids, respectively, in human cerebrospinal fluid. We demonstrate here that variant p3-Alc C termini are modulated by FAD-linked presenilin 1 mutations increasing minor beta-amyloid species Abeta42, and these mutations alter the level of minor p3-Alc species. However, the magnitudes of C-terminal alteration of p3-Alc(alpha), p3-Alc(beta), and p3-Alc(gamma) were not equivalent, suggesting that one type of gamma-secretase dysfunction does not appear in the phenotype equivalently in the cleavage of type I membrane proteins. Because these C-terminal alterations are detectable in human cerebrospinal fluid, the use of a substrate panel, including Alcs and APP, may be effective to detect gamma-secretase dysfunction in the prepathogenic state of Alzheimer disease subjects.

  20. He+ irradiation induced cracking and exfoliating on the surface of Ti3AlC2

    NASA Astrophysics Data System (ADS)

    Shen, H. H.; Ao, L.; Li, F. Z.; Peng, S. M.; Zhang, H. B.; Sun, K.; Zu, X. T.

    2017-03-01

    We report a systematic study of the effects of a 400 keV helium ion beam irradiation on the surface morphology and crystal structure of Ti3AlC2 by combined scanning electron microscopy, grazing incidence X-ray diffraction and transmission electron microscopy. Helium irradiation experiments were performed at both room temperature and 500 °C, respectively, with fluence up to 2.0 × 1017 He+/cm2. After irradiation, intragranular orientated cracks grew along the (10 1 bar 0)Ti3AlC2 plane and the surface has started to exfoliate. The formation of the cracks is mainly attributed to the reduction of the lattice parameter along the a direction induced by ion irradiation, and the crack growth is affected by the grain size and the content of impurity phase TiAl3. The surface exfoliation is due to the blistering of He bubbles at the projected depth.

  1. Identification of AlcR, an AraC-Type Regulator of Alcaligin Siderophore Synthesis in Bordetella bronchiseptica and Bordetella pertussis

    PubMed Central

    Pradel, Elizabeth; Guiso, Nicole; Locht, Camille

    1998-01-01

    A Fur titration assay was used to isolate DNA fragments bearing putative Fur binding sites (FBS) from a partial Bordetella bronchiseptica genomic DNA library. A recombinant plasmid bearing a 3.5-kb DNA insert was further studied. Successive deletions in the cloned fragment enabled us to map a putative FBS at about 2 kb from one end. Sequence analysis revealed the presence of an FBS upstream from a new gene encoding an AraC-type transcriptional regulator. The deduced protein displays similarity to PchR, an activator of pyochelin siderophore and ferripyochelin receptor synthesis in Pseudomonas aeruginosa. Homologous genes in Bordetella pertussis and Bordetella parapertussis were PCR amplified, and sequence comparisons indicated a very high conservation in the three species. The B. pertussis and B. bronchiseptica chromosomal genes were inactivated by allelic exchange. Under low-iron growth conditions, the mutants did not secrete the alcaligin siderophore and lacked AlcC, an alcaligin biosynthetic enzyme. Alcaligin production was restored after transformation with a plasmid bearing the wild-type gene. On the basis of its role in regulation of alcaligin biosynthesis, the new gene was designated alcR. Additional sequence determination showed that alcR is located about 2 kb downstream from the alcABC operon and is transcribed in the same orientation. Two tightly linked open reading frames, alcD and alcE, were identified between alcC and alcR. AlcE is a putative iron-sulfur protein; AlcD shows no homology with the proteins in the database. The production of major virulence factors and colonization in the mouse respiratory infection model are AlcR independent. PMID:9473041

  2. Simulated moose (Alces alces L.) browsing increases accumulation of secondary metabolites in bilberry (Vaccinium myrtillus L.) along gradients of habitat productivity and solar radiation.

    PubMed

    Persson, Inga-Lill; Julkunen-Tiitto, Riitta; Bergström, Roger; Wallgren, Märtha; Suominen, Otso; Danell, Kjell

    2012-10-01

    We have addressed the impact of moose (Alces alces L.) on accumulation of secondary metabolites, lignin, and nitrogen in bilberry (Vaccinium myrtillus L.) along gradients of habitat productivity and solar radiation. The study was conducted within a long-term research project on direct and indirect impacts of moose on the ecosystem. In the experiment, browsing, defecation, and urination corresponding to four different moose densities were simulated for eight years before bilberry tissue was collected and analyzed. Some quantitatively dominant flavonoids were affected by the simulated moose browsing and by habitat productivity and light. The content of flavonoids increased with increasing moose density and light, and decreased with increasing habitat productivity. The higher concentration of secondary metabolites in bilberry from nutrient-poor sites may have resulted from the increased photosynthesis relative to growth, which facilitated secondary metabolism. The higher concentration of secondary metabolites in plants subjected to simulated moose- herbivory might have been caused in part by loss of biomass. In addition, in areas with high biomass loss, i.e., high moose density, a more open canopy was created and more solar radiation could have induced secondary metabolism.

  3. Sarcocystis in moose (Alces alces): molecular identification and phylogeny of six Sarcocystis species in moose, and a morphological description of three new species.

    PubMed

    Dahlgren, Stina S; Gjerde, Bjørn

    2008-06-01

    Muscle tissues from 34 moose from Southeastern Norway and two moose from Canada were examined. Sarcocysts were excised and morphologically classified by light microscopy, and some cysts were further examined by scanning electron microscopy or DNA amplification and sequencing at the small subunit (ssu) rRNA gene. In Norwegian moose, three sarcocyst types were recognized, yet five Sarcocystis species were found by sequence analysis. New names were proposed for three species which could be characterised by both morphological and molecular methods, i.e., Sarcocystis alces, Sarcocystis ovalis, and Sarcocystis scandinavica. S. alces was the most prevalent species, whereas S. scandinavica and the two unnamed species were rare and might either use another principal intermediate host or a rare definitive host. The five species in Norwegian moose were different from Sarcocystis alceslatrans isolated from a Canadian moose. Phylogenetic analyses based on complete ssu rRNA gene sequences revealed a close relationship between the six Sarcocystis species from moose and species from reindeer and Sika deer. We conclude that molecular methods are necessary for unequivocal species identification, as different cervid hosts harbour morphologically indistinguishable sarcocysts.

  4. Influence of forage preferences and habitat use on 13C and 15N abundance in wild caribou (Rangifer tarandus caribou) and moose (Alces alces) from Canada.

    PubMed

    Drucker, Dorothee G; Hobson, Keith A; Ouellet, Jean-Pierre; Courtois, Rehaume

    2010-03-01

    Stable isotope composition (delta(13)C and delta(15)N) of moose (Alces alces) and caribou (Rangifer tarandus) hair from the boreal forest of Jacques-Cartier Park and Cote-Nord (Quebec) and arctic tundra of Queen Maud Gulf and Southampton Island (Nunavut) was investigated as an indicator of dietary preferences and habitat use. Values of delta(13)C(hair) and delta(15)N(hair) in moose were consistently lower compared to those of caribou. This is consistent with the depletion in (13)C and (15)N in the plants preferred by moose, essentially browse (shrub and tree leaves), compared to caribou forage, which included significant amounts of graminoids, lichen and fungi. The delta(13)C(hair) values of caribou differed between closed boreal forest and open-tundra ecosystems. This pattern followed that expected from the canopy effect observed in plant communities. Variation in delta(15)N(hair) values of caribou was probably linked to the effect of different climatic conditions on plant communities. This study underlines the potential of isotopic analysis for studies on diet and habitat selection within a pure C(3) plant environment.

  5. Study of the horizontal and vertical dispersion at the atmospheric flow at the Alc

    NASA Astrophysics Data System (ADS)

    Pires, L.; Roballo, S.; Fisch, G.; Avelar, A.; Girardi, R.; Gielow, R.

    2009-04-01

    The Alcântara Launching Center (ALC) region is situated in the north coast of the Maranhão state and it was simulated in a wind tunnel with an open circuit at Institute Technologic of Aeronautics (ITA). The ALC topography possesses typical characteristics of smooth surface (ocean) close to a roughness surface (continent). The local coast has a relative topographical variation (coastal cliffs) with inclination and 50 m height, being the top a plain area. A mock-up model has been constructed to be inserted at the wind tunnel for the measurements. The Integration Mobile Tower (IMT) is placed at 150 m from the coastal cliff. Consequently the rockets can suffer the influence from intense turbulence resultant of the modification of the wind profile of the proceeding from the ocean as ascending vertically from thr IMT. It was used the Particle Image Velocimetrýs (PIV) technique for the analysis of the vertical dispersion in the central lane from the ocean until the IMT and the hot wire anemometry technique for the horizontal dispersion. The analysis of the vertical dispersion was carried through locating the PIV transversally to the model that simulates the ALC. The vorticity generated above of the coastal cliff has the same intensity of the vorticity generated at the IMT (-2000 s-1) being these the zones of higher turbulence. With regard to the horizontal flow one noticed that the low levels (below 10 m) presented the great speed fluctuations close the coastal cliff. In the high levels (above 10 m), this fluctuations diminished. The high values of turbulent intensities after the step, in the low levels, due to recirculation characterized for low values of speeds average and hight speed fluctuations also was verified in the vertical dispersion.

  6. Extreme Oxidative Durability of TBCs on Ti2AlC MAX Phases

    NASA Technical Reports Server (NTRS)

    Smialek, James L.; Harder, Bryan J.; Garg, Anita

    2015-01-01

    APS and PS-PVD YSZ thermal barrier coatings, applied directly to oxidation resistant Ti2AlC substrates, were oxidized in interrupted furnace tests. Temperature was advanced in 50C intervals from 1100 to 1300C, each 500 h long with eleven cooling cycles. Damage only initiated on the APS coating at 1300C after 15 h, with complete delamination after 500 h. The PS-PVD coating survived all testing. Weight change and metallographic analyses indicate that the YSZ-Ti2AlC systems sustained alumina scale growth of 30-40 m. In comparison, widely used Pt-aluminide bondcoats on single crystal superalloy turbine blades exhibit TBC lives equivalent to alumina scale growth up to 7 m, equivalent to just 200 h at 1200C. It is demonstrated that 25x TBC life improvement (or 180C temperature increase) resulted from the close CTE match of Ti2AlC with those of alumina and YSZ.

  7. Preparation of high concentration polyaluminum chloride with high content of Alb or Alc.

    PubMed

    Zhao, Changwei; Zhang, Jingbo; Luan, Zhaokun; Peng, Xianjia; Ren, Xiaojing

    2009-01-01

    A novel membrane distillation concentration method was used to prepare high concentration polyaluminum chloride (PACl) with high content of Alb or Alc. 2.52 mol/L PACl1 with 88% Alb and 2.38 mol/L PACl2 with 61% Alc were successfully prepared. Three coagulants, AlCl3, PACl1 and PACl2 were investigated on their hydrolysis behavior and speciation under different conditions. The effects of pH and dilution ratio on Al species distribution were investigated by ferron assay. Experimental result showed that pH had a significant effect on Al species distribution for the three coagulants. Dilution ratio had little effects on Alb and Alc distribution in whole dilution process except the beginning for PACl1 and PACl2. The results indicated that transformation of Al depends largely on their original composition. AlCl3 was the most unstable coagulant among these three coagulants during hydrolysis process. PACl1 and PACl2 with significant amounts of highly charged and stable polynuclear aluminum hydrolysis products were less affected by the hydrolysis conditions and could maintain high speciation stability under various conditions.

  8. PARP1 promotes nucleotide excision repair through DDB2 stabilization and recruitment of ALC1

    PubMed Central

    Vrouwe, Mischa G.; Marteijn, Jurgen A.; Typas, Dimitris; Luijsterburg, Martijn S.; Cansoy, Medine; Hensbergen, Paul; Deelder, André; de Groot, Anton; Matsumoto, Syota; Sugasawa, Kaoru; Thoma, Nicolas; Vermeulen, Wim; Vrieling, Harry

    2012-01-01

    The WD40-repeat protein DDB2 is essential for efficient recognition and subsequent removal of ultraviolet (UV)-induced DNA lesions by nucleotide excision repair (NER). However, how DDB2 promotes NER in chromatin is poorly understood. Here, we identify poly(ADP-ribose) polymerase 1 (PARP1) as a novel DDB2-associated factor. We demonstrate that DDB2 facilitated poly(ADP-ribosyl)ation of UV-damaged chromatin through the activity of PARP1, resulting in the recruitment of the chromatin-remodeling enzyme ALC1. Depletion of ALC1 rendered cells sensitive to UV and impaired repair of UV-induced DNA lesions. Additionally, DDB2 itself was targeted by poly(ADP-ribosyl)ation, resulting in increased protein stability and a prolonged chromatin retention time. Our in vitro and in vivo data support a model in which poly(ADP-ribosyl)ation of DDB2 suppresses DDB2 ubiquitylation and outline a molecular mechanism for PARP1-mediated regulation of NER through DDB2 stabilization and recruitment of the chromatin remodeler ALC1. PMID:23045548

  9. Increased levels of plasma p3-alcα35, a major fragment of Alcadeinα by γ-secretase cleavage, in Alzheimer's disease.

    PubMed

    Omori, Chiori; Kaneko, Madoka; Nakajima, Etsuko; Akatsu, Hiroyasu; Waragai, Masaaki; Maeda, Masahiro; Morishima-Kawashima, Maho; Saito, Yuhki; Nakaya, Tadashi; Taru, Hidenori; Yamamoto, Tohru; Asada, Takashi; Hata, Saori; Suzuki, Toshiharu

    2014-01-01

    p3-Alcα is a metabolic fragment of Alcadeinα (Alcα). Similar to the generation of the p3 fragment from amyloid-β protein precursor (AβPP) processing, Alcα is cleaved by α- and γ-secretases, leading to the secretion of p3-Alcα peptides into cerebrospinal fluid (CSF). p3-Alcα is also detected in the plasma, similar to amyloid-β (Aβ), which is a metabolic fragment of AβPP cleaved by amyloidogenic β- and γ-secretases. Because p3-Alcα is a non-aggregatable and stable peptide, unlike aggregatable Aβ and metabolically labile p3 of AβPP, the changes of p3-Alcα in quality and/or quantity in CSF and plasma are expected to be a marker for assessing alteration of substrate cleavage by γ-secretase, such as Aβ generation from AβPP. The present study describes a sandwich enzyme-linked immunosorbent assay for quantifying levels of p3-Alcα35, the major form of the p3-Alcα species, and examines levels of p3-Alcα35 in the plasma of three independent Japanese cohorts. In two of the three cohorts, the p3-Alcα35 levels were significantly increased with a concomitant decrease in the Mini-Mental State Examination score, or in clinically diagnosed Alzheimer's disease (AD) patients, when compared with age-matched non-demented subjects. The values were significantly lower in AD subjects who were administered donepezil, when compared to AD subjects without donepezil treatment. The increase in plasma p3-Alcα35 levels may indicate an endophenotype in subjects in whom AD is due to a progressing cognitive impairment in subjects with a γ-secretase malfunction, or a disorder of the clearance of peptides.

  10. Polyamine metabolism in ripening tomato fruit. II. Polyamine metabolism and synthesis in relation to enhanced putrescine content and storage life of alc tomato fruit

    SciTech Connect

    Rastogi, R.; Davies, P.J. )

    1991-01-01

    The fruit of the Alcobaca landrace of tomato (Lycopersicon esculentum Mill.) have prolonged keeping qualities (determined by the allele alc) and contain three times as much putrescine as the standard Rutgers variety (Alc) at the ripe stage. Polyamine metabolism and biosynthesis were compared in fruit from Rutgers and Rutgers-alc-a near isogenic line possessing the allele alc, at four different stages of ripening. The levels of soluble polyamine conjugates as well as wall bound polyamines in the pericarp tissue and jelly were very low or nondetectable in both genotypes. The increase in putrescine content in alc pericarp is not related to normal ripening as it occurred with time and whether or not the fruit ripened. Pericarp discs of both normal and alc fruit showed a decrease in the metabolism of (1,4-{sup 14}C)putrescine and (terminal labeled-{sup 3}H)spermidine with ripening, but there were no significant differences between the two genotypes. The activity of ornithine decarboxylase was similar in the fruit pericarp of the two lines. Arginine decarboxylase activity decreased during ripening in Rutgers but decreased and rose again in Rutgers-alc fruit, and as a result it was significantly higher in alc fruit than in the normal fruit at the ripe stage. The elevated putrescine levels in alc fruit appear, therefore, to be due to an increase in the activity of arginine decarboxylase.

  11. Fibrolytic Bacteria Isolated from the Rumen of North American Moose (Alces alces) and Their Use as a Probiotic in Neonatal Lambs

    PubMed Central

    Ishaq, Suzanne L.; Kim, Christina J.; Reis, Doug; Wright, André-Denis G.

    2015-01-01

    Fibrolytic bacteria were isolated from the rumen of North American moose (Alces alces), which eat a high-fiber diet of woody browse. It was hypothesized that fibrolytic bacteria isolated from the moose rumen could be used as probiotics to improve fiber degradation and animal production. Thirty-one isolates (Bacillus, n = 26; Paenibacillus, n = 1; and Staphylococcus, n = 4) were cultured from moose rumen digesta samples collected in Vermont. Using Sanger sequencing of the 16S rRNA gene, culturing techniques, and optical densities, isolates were identified and screened for biochemical properties important to plant carbohydrate degradation. Five isolates were selected as candidates for use as a probiotic, which was administered daily to neonate lambs for 9 weeks. It was hypothesized that regular administration of a probiotic to improve fibrolysis to neonate animals through weaning would increase the developing rumen bacterial diversity, increase animal production, and allow for long-term colonization of the probiotic species. Neither weight gain nor wool quality was improved in lambs given a probiotic, however, dietary efficiency was increased as evidenced by the reduced feed intake (and rearing costs) without a loss to weight gain. Experimental lambs had a lower acetate to propionate ratio than control lambs, which was previously shown to indicate increased dietary efficiency. Fibrolytic bacteria made up the majority of sequences, mainly Prevotella, Butyrivibrio, and Ruminococcus. While protozoal densities increased over time and were stable, methanogen densities varied greatly in the first six months of life for lambs. This is likely due to the changing diet and bacterial populations in the developing rumen. PMID:26716685

  12. Identification of the pregnancy-associated glycoprotein family (PAGs) and some aspects of placenta development in the European moose (Alces alces L.).

    PubMed

    Lipka, Aleksandra; Panasiewicz, Grzegorz; Majewska, Marta; Bieniek-Kobuszewska, Martyna; Saveljev, Alexander P; Pankratov, Andrey P; Szafranska, Bozena

    2016-12-01

    This study describes the identification and a broad-based characterization of the pregnancy-associated glycoprotein (PAG) genes expressed in the synepitheliochorial placenta of the Alces alces (Aa; N = 51). We used: (1) both size measurements (cm) of various Aa embryos/fetuses (crown-rump length) and placentomes (PLCs); (2) PCR, Southern and sequencing; (3) Western-blot for total placental glycoproteins; (4) deglycosylation of total cotyledonary proteins; and (5) double heterologous IHC for cellular immune-localization of the PAGs as pregnancy advanced (50-200 days post coitum). The crown-rump length and PLC size measurements permitted a novel pattern estimation of various pregnancy stages in wild Aa. The PLC number varied (5-21) and was the greatest at the mid and late stages of gestation in females bearing singletons or twins. The genomic existence of the identified PAG-like family was named AaPAG-L. Amplicon profiles of the AaPAG-L varied in the number and length (118-2000 bp). Southern with porcine cDNA probes confirmed specificity and revealed dominant AaPAG-L amplicons in males and females. Nucleotide sequences of the AaPAG-L amplicons shared 86.27% homology with the bovine PAG1 (bPAG1) gene. Amino acid AaPAG sequences revealed in silico 88.23% to 100% homology with the bPAG1 precursor. Western-blots revealed a dominant mature 55 kDa AaPAG fraction, and the major ∼48 kDa glycosylated form that was deglycosylated to ∼44 kDa. The AaPAG-Ls was immuno-localized to mono- and bi-nucleated trophectodermal cells (TRD-chorionic epithelium), where signal intensity resembled intense TRD proliferation within developing PLCs as pregnancy advanced. This is the first study identifying the AaPAG-L family in the largest representative among the Cervidae.

  13. Fibrolytic Bacteria Isolated from the Rumen of North American Moose (Alces alces) and Their Use as a Probiotic in Neonatal Lambs.

    PubMed

    Ishaq, Suzanne L; Kim, Christina J; Reis, Doug; Wright, André-Denis G

    2015-01-01

    Fibrolytic bacteria were isolated from the rumen of North American moose (Alces alces), which eat a high-fiber diet of woody browse. It was hypothesized that fibrolytic bacteria isolated from the moose rumen could be used as probiotics to improve fiber degradation and animal production. Thirty-one isolates (Bacillus, n = 26; Paenibacillus, n = 1; and Staphylococcus, n = 4) were cultured from moose rumen digesta samples collected in Vermont. Using Sanger sequencing of the 16S rRNA gene, culturing techniques, and optical densities, isolates were identified and screened for biochemical properties important to plant carbohydrate degradation. Five isolates were selected as candidates for use as a probiotic, which was administered daily to neonate lambs for 9 weeks. It was hypothesized that regular administration of a probiotic to improve fibrolysis to neonate animals through weaning would increase the developing rumen bacterial diversity, increase animal production, and allow for long-term colonization of the probiotic species. Neither weight gain nor wool quality was improved in lambs given a probiotic, however, dietary efficiency was increased as evidenced by the reduced feed intake (and rearing costs) without a loss to weight gain. Experimental lambs had a lower acetate to propionate ratio than control lambs, which was previously shown to indicate increased dietary efficiency. Fibrolytic bacteria made up the majority of sequences, mainly Prevotella, Butyrivibrio, and Ruminococcus. While protozoal densities increased over time and were stable, methanogen densities varied greatly in the first six months of life for lambs. This is likely due to the changing diet and bacterial populations in the developing rumen.

  14. Prevalence of Borrelia burgdorferi in Ixodes ricinus ticks collected from moose (Alces alces) and roe deer (Capreolus capreolus) in southern Norway.

    PubMed

    Kjelland, Vivian; Ytrehus, Bjørnar; Stuen, Snorre; Skarpaas, Tone; Slettan, Audun

    2011-06-01

    As part of a larger survey, ears from 18 roe deer (Capreolus capreolus) and 52 moose (Alces alces) shot in the 2 southernmost counties in Norway were collected and examined for Ixodes ricinus ticks. Seventy-two adult ticks, 595 nymphs, and 267 larvae from the roe deer, and 182 adult ticks, 433 nymphs, and 70 larvae from the moose were investigated for infection with Borrelia burgdorferi sensu lato (s.l.). The results showed the presence of B. burgdorferi s.l. DNA in 2.9% of the nymphs collected from roe deer and in 4.4% of the nymphs and 6.0% of the adults collected from moose. The spirochetes were not detected in adult ticks from roe deer, or in larvae feeding on roe deer or moose. In comparison, the mean infection prevalences in questing I. ricinus collected from the same geographical area were 0.5% infection in larvae, 24.5% in nymphs, and 26.9% in adults. The most prevalent B. burgdorferi genospecies identified in ticks collected from roe deer was B. afzelii (76.5%), followed by B. garinii (17.6%), and B. burgdorferi sensu stricto (5.9%). Only B. afzelii (76.7%) and B. garinii (23.3%) were detected in ticks collected from moose. The present study indicates a lower prevalence of B. burgdorferi infection in I. ricinus ticks feeding on roe deer and moose compared to questing ticks. This is the first study to report B. burgdorferi s.l. prevalence in ticks removed from cervids in Norway.

  15. Testing of advanced liquefaction concepts in HTI Run ALC-1: Coal cleaning and recycle solvent treatment

    SciTech Connect

    Robbins, G.A.; Winschel, R.A.; Burke, F.P.; Derbyshire, F.L.; Givens, E.N.; Hu, J.; Lee, T.L.K.; Miller, J.E.; Stephens, H.P.; Peluso, M.

    1996-09-01

    In 1991, the Department of Energy initiated the Advanced Liquefaction Concepts Program to promote the development of new and emerging technology that has potential to reduce the cost of producing liquid fuels by direct coal liquefaction. Laboratory research performed by researchers at CAER, CONSOL, Sandia, and LDP Associates in Phase I is being developed further and tested at the bench scale at HTI. HTI Run ALC-1, conducted in the spring of 1996, was the first of four planned tests. In Run ALC-1, feed coal ash reduction (coal cleaning) by oil agglomeration, and recycle solvent quality improvement through dewaxing and hydrotreatment of the recycle distillate were evaluated. HTI`s bench liquefaction Run ALC-1 consisted of 25 days of operation. Major accomplishments were: 1) oil agglomeration reduced the ash content of Black Thunder Mine coal by 40%, from 5.5% to 3.3%; 2) excellent coal conversion of 98% was obtained with oil agglomerated coal, about 3% higher than the raw Black Thunder Mine coal, increasing the potential product yield by 2-3% on an MAF coal basis; 3) agglomerates were liquefied with no handling problems; 4) fresh catalyst make-up rate was decreased by 30%, with no apparent detrimental operating characteristics, both when agglomerates were fed and when raw coal was fed (with solvent dewaxing and hydrotreating); 5) recycle solvent treatment by dewaxing and hydrotreating was demonstrated, but steady-state operation was not achieved; and 6) there was some success in achieving extinction recycle of the heaviest liquid products. Performance data have not been finalized; they will be available for full evaluation in the new future.

  16. The poly(ADP-ribose)-dependent chromatin remodeler Alc1 induces local chromatin relaxation upon DNA damage

    PubMed Central

    Sellou, Hafida; Lebeaupin, Théo; Chapuis, Catherine; Smith, Rebecca; Hegele, Anna; Singh, Hari R.; Kozlowski, Marek; Bultmann, Sebastian; Ladurner, Andreas G.; Timinszky, Gyula; Huet, Sébastien

    2016-01-01

    Chromatin relaxation is one of the earliest cellular responses to DNA damage. However, what determines these structural changes, including their ATP requirement, is not well understood. Using live-cell imaging and laser microirradiation to induce DNA lesions, we show that the local chromatin relaxation at DNA damage sites is regulated by PARP1 enzymatic activity. We also report that H1 is mobilized at DNA damage sites, but, since this mobilization is largely independent of poly(ADP-ribosyl)ation, it cannot solely explain the chromatin relaxation. Finally, we demonstrate the involvement of Alc1, a poly(ADP-ribose)- and ATP-dependent remodeler, in the chromatin-relaxation process. Deletion of Alc1 impairs chromatin relaxation after DNA damage, while its overexpression strongly enhances relaxation. Altogether our results identify Alc1 as an important player in the fast kinetics of the NAD+- and ATP-dependent chromatin relaxation upon DNA damage in vivo. PMID:27733626

  17. Inhibition of transcription of cytosine-containing DNA in vitro by the alc gene product of bacteriophage T4.

    PubMed Central

    Drivdahl, R H; Kutter, E M

    1990-01-01

    The alc gene product (gpalc) of bacteriophage T4 inhibits the transcription of cytosine-containing DNA in vivo. We examined its effect on transcription in vitro by comparing RNA polymerase isolated from Escherichia coli infected with either wild-type T4D+ or alc mutants. A 50 to 60% decline in RNA polymerase activity, measured on phage T7 DNA, was observed by 1 min after infection with either T4D+ or alc mutants; this did not occur when the infecting phage lacked gpalt. In the case of the T4D+ strain but not alc mutants, this was followed by a further decrease. By 5 min after infection the activity of alc mutants was 1.5 to 2.5 times greater than that of the wild type on various cytosine-containing DNA templates, whereas there was little or no difference in activity on T4 HMdC-DNA, in agreement with the in vivo specificity. Effects on transcript initiation and elongation were distinguished by using a T7 phage DNA template. Rifampin challenge, end-labeling with [gamma-32P]ATP, and selective initiation with a dinucleotide all indicate that the decreased in vitro activity of the wild-type polymerase relative to that of the alc mutants was due to inhibition of elongation, not to any difference in initiation rates. Wild-type (but not mutated) gpalc copurified with RNA polymerase on heparin agarose but not in subsequent steps. Immunoprecipitation of modified RNA polymerase also indicated that gpalc was not tightly bound to RNA polymerase intracellularly. It thus appears likely that gpalc inhibits transcript elongation on cytosine-containing DNA by interacting with actively transcribing core polymerase as a complex with the enzyme and cytosine-rich stretches of the template. Images PMID:2185231

  18. Preparation of Al-Ce hybrid adsorbent and its application for defluoridation of drinking water.

    PubMed

    Liu, Han; Deng, Shubo; Li, Zhijian; Yu, Gang; Huang, Jun

    2010-07-15

    A novel Al-Ce hybrid adsorbent with high sorption capacity for fluoride was prepared through the coprecipitation method in this study, and its preparation conditions were optimized. X-ray diffraction (XRD) and scanning electron microscope (SEM) results showed that the hybrid adsorbent was of amorphous structure and constituted by some aggregated nanoparticles. As the adsorbent had the zero point of zeta potential at pH 9.6, it was very effective in fluoride removal from aqueous solution via electrostatic interaction. The results of sorption experiments including sorption kinetics, isotherms, and the effect of solution pH showed that the sorption of fluoride on the Al-Ce adsorbent was fast and pH-dependent. Especially, the adsorbent had high sorption capacity up to 27.5 mg g(-1) for fluoride at the equilibrium fluoride concentration of 1 mg L(-1), much higher than that of the conventional adsorbents. Fourier transform infrared (FTIR) analysis and zeta potential measurement showed that the hydroxyl groups and the protonated hydroxyl groups on the adsorbent surface were involved in the fluoride adsorption.

  19. Trace elements in moose (Alices alces) found dead in Northwestern Minnesota, USA

    USGS Publications Warehouse

    Custer, T.W.; Cox, E.; Gray, B.

    2004-01-01

    The moose (Alces alces) population in bog and forest areas of Northwestern Minnesota has declined for more than 25 years, and more recently the decline is throughout Northwestern Minnesota. Both deficiencies and elevations in trace elements have been linked to the health of moose worldwide. The objective of this study was to evaluate whether trace element toxicity or deficiency may have contributed to the decline of moose in Northwestern Minnesota. Livers of 81 moose found dead in Northwestern Minnesota in 1998 and 1999 were analyzed for trace elements. With the exception of selenium (Se) and copper (Cu), trace elements were not at toxic or deficient levels based on criteria set for cattle. Selenium concentrations in moose livers based on criteria set for cattle were deficient in 3.7% of livers and at a chronic toxicity level in 16% of livers. Copper concentrations based on criteria set for cattle were deficient in 39.5% of livers, marginally deficient in 29.5% of livers and adequate in 31% of livers. Moose from agricultural areas had higher concentrations, on average, of Cd, Cu, Mo and Se in their livers than moose from bog and forest areas. Older moose had higher concentrations of Cd and Zn, and lower concentrations of Cu than younger moose. Copper deficiency, which has been associated with population declines of moose in Alaska and Sweden, may be a factor contributing to the decline of moose in Northwestern Minnesota. (C) 2004 Elsevier B.V. All rights reserved.

  20. Evaluation of an Al-Ce alloy for laser additive manufacturing

    DOE PAGES

    Plotkowski, A.; Rios, O.; Sridharan, N.; ...

    2016-12-27

    Our present research in metal additive manufacturing (AM) focuses on designing processing parameters around existing alloys designed for traditional manufacturing. However, to maximize the benefits of AM, alloys should be designed to specifically take advantage of the unique thermal conditions of these processes. Furthermore, our study focuses on the development of a design methodology for alloys in AM, using a newly developed Al-Ce alloy as an initial case study. To evaluate the candidacy of this system for fusion based additive manufacturing, single-line laser melts were made on cast Al-12Ce plates using three different beam velocities (100, 200, and 300 mm/min).more » The microstructure was evaluated in the as-melted and heat treated conditions (24 hrs at 300°C). An extremely fine microstructure was observed within the weld pools, evolving from eutectic at the outer solid-liquid boundaries to a primary Al FCC dendritic/cellular structure nearer the melt-pool centerline. We rationalized the observed microstructures through the construction of a microstructure selection map for the Al-Ce binary system, which will be used to enable future alloy design. Interestingly, the heat treated samples exhibited no microstructural coarsening.« less

  1. Evaluation of an Al-Ce alloy for laser additive manufacturing

    SciTech Connect

    Plotkowski, A.; Rios, O.; Sridharan, N.; Sims, Z.; Unocic, K.; Ott, R. T.; Dehoff, R. R.; Babu, S. S.

    2016-12-27

    Our present research in metal additive manufacturing (AM) focuses on designing processing parameters around existing alloys designed for traditional manufacturing. However, to maximize the benefits of AM, alloys should be designed to specifically take advantage of the unique thermal conditions of these processes. Furthermore, our study focuses on the development of a design methodology for alloys in AM, using a newly developed Al-Ce alloy as an initial case study. To evaluate the candidacy of this system for fusion based additive manufacturing, single-line laser melts were made on cast Al-12Ce plates using three different beam velocities (100, 200, and 300 mm/min). The microstructure was evaluated in the as-melted and heat treated conditions (24 hrs at 300°C). An extremely fine microstructure was observed within the weld pools, evolving from eutectic at the outer solid-liquid boundaries to a primary Al FCC dendritic/cellular structure nearer the melt-pool centerline. We rationalized the observed microstructures through the construction of a microstructure selection map for the Al-Ce binary system, which will be used to enable future alloy design. Interestingly, the heat treated samples exhibited no microstructural coarsening.

  2. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Electronic Structure and Elastic Properties of Ti3AlC from First-Principles Calculations

    NASA Astrophysics Data System (ADS)

    Du, Yu-Lei

    2009-11-01

    We perform a first-principles study on the electronic structure and elastic properties of Ti3AlC with an antiperovskite structure. The absence of band gap at the Fermi level and the finite value of the density of states at the Fermi energy reveal the metallic behavior of this compound. The elastic constants of Ti3AlC are derived yielding c11 = 356 GPa, c11 = 55 GPa, c44 = 157 GPa. The bulk modulus B, shear modulus G and Young's modulus E are determined to be 156, 151 and 342 GPa, respectively. These properties are compared with those of Ti3AlC2 and Ti2AlC with a layered structure in the Ti-Al-C system and Fe3AlC with the same antiperovskite structure.

  3. Effect of neutron irradiation on defect evolution in Ti3SiC2 and Ti2AlC

    DOE PAGES

    Tallman, Darin J.; He, Lingfeng; Garcia-Diaz, Brenda L.; ...

    2015-10-23

    Here, we report on the characterization of defects formed in polycrystalline Ti3SiC2 and Ti2AlC samples exposed to neutron irradiation – up to 0.1 displacements per atom (dpa) at 350 ± 40 °C or 695 ± 25 °C, and up to 0.4 dpa at 350 ± 40 °C. Black spots are observed in both Ti3SiC2 and Ti2AlC after irradiation to both 0.1 and 0.4 dpa at 350 °C. After irradiation to 0.1 dpa at 695 °C, small basal dislocation loops, with a Burgers vector of b = 1/2 [0001] are observed in both materials. At 9 ± 3 and 10 ±more » 5 nm, the loop diameters in the Ti3SiC2 and Ti2AlC samples, respectively, were comparable. At 1 × 1023 loops/m3, the dislocation loop density in Ti2AlC was ≈1.5 orders of magnitude greater than in Ti3SiC2, at 3 x 1021 loops/m3. After irradiation at 350 °C, extensive microcracking was observed in Ti2AlC, but not in Ti3SiC2. The room temperature electrical resistivities increased as a function of neutron dose for all samples tested, and appear to saturate in the case of Ti3SiC2. The MAX phases are unequivocally more neutron radiation tolerant than the impurity phases TiC and Al2O3. Based on these results, Ti3SiC2 appears to be a more promising MAX phase candidate for high temperature nuclear applications than Ti2AlC.« less

  4. Carbon diffusion in alumina from carbon and Ti{sub 2}AlC thin films

    SciTech Connect

    Guenette, Mathew C.; Tucker, Mark D.; Bilek, Marcela M. M.; McKenzie, David R.; Ionescu, Mihail

    2011-04-15

    Carbon diffusion is observed in single crystal {alpha}-Al{sub 2}O{sub 3} substrates from carbon and Ti{sub 2}AlC thin films synthesized via pulsed cathodic arc deposition. Diffusion was found to occur at substrate temperatures of 570 deg. C and above. The diffusion coefficient of carbon in {alpha}-Al{sub 2}O{sub 3} is estimated to be of the order 3x10{sup -13} cm{sup 2}/s for deposition temperatures in the 570-770{sup o}C range by examining elastic recoil detection analysis (ERDA) elemental depth profiles. It is suggested that an appropriate diffusion barrier may be useful when depositing carbon containing thin films on {alpha}-Al{sub 2}O{sub 3} substrates at high temperatures.

  5. Imaging spread-F structures using GPS observations at Alcântara, Brazil

    NASA Astrophysics Data System (ADS)

    Musman, S.; Jahn, J.-M.; LaBelle, J.; Swartz, W. E.

    During October 1994, a dual-frequency GPS receiver was operated in Alcântara, Brazil, at the same site where the Cornell University Portable Radar Interferometer (CUPRI) was performing spread-F measurements for an ongoing rocket campaign. We present data for two nights during which several spread-F plumes drifted through the field-of-view of CUPRI. Fluctuations in the total electron content (TEC) measured with the GPS receiver were correlated with those plumes. We define a “roughness” measure from a specialized high frequency filter. Plots of “roughness” in a magnetic longitude versus time space show initially low activity followed by regions of dramatic localized onsets and a slower subsequent decline. Features in the roughness image are well-correlated with plumes in the CUPRI backscatter power map.

  6. Identification and Characterization of alcR, a Gene Encoding an AraC-Like Regulator of Alcaligin Siderophore Biosynthesis and Transport in Bordetella pertussis and Bordetella bronchiseptica

    PubMed Central

    Beaumont, Fiona C.; Kang, Ho Young; Brickman, Timothy J.; Armstrong, Sandra K.

    1998-01-01

    A Bordetella bronchiseptica iron transport mutant was isolated following an enrichment procedure based on streptonigrin resistance. The mutant displayed a growth defect on iron-restricted medium containing ferric alcaligin as the sole iron source. In addition to the apparent inability to acquire iron from the siderophore, the mutant failed to produce alcaligin as well as two known iron-regulated proteins, one of which is the AlcC alcaligin biosynthesis protein. A 1.6-kb KpnI-PstI Bordetella pertussis DNA fragment mapping downstream of the alcaligin biosynthesis genes alcABC restored both siderophore biosynthesis and expression of the iron-regulated proteins to the mutant. Nucleotide sequencing of this complementing 1.6-kb region identified an open reading frame predicted to encode a protein with strong similarity to members of the AraC family of transcriptional regulators, for which we propose the gene designation alcR. Primer extension analysis localized an iron-regulated transcription initiation site upstream of the alcR open reading frame and adjacent to sequences homologous to the consensus Fur repressor binding site. The AlcR protein was produced by using an Escherichia coli expression system and visualized in electrophoretic gels. In-frame alcR deletion mutants of B. pertussis and B. bronchiseptica were constructed, and the defined mutants exhibited the alcR mutant phenotype, characterized by the inability to produce and transport alcaligin and express the two iron-repressed proteins. The cloned alcR gene provided in trans restored these siderophore system activities to the mutants. Together, these results indicate that AlcR is involved in the regulation of Bordetella alcaligin biosynthesis and transport genes and is required for their full expression. PMID:9473040

  7. Discovery of carbon-vacancy ordering in Nb4AlC3–x under the guidance of first-principles calculations

    PubMed Central

    Zhang, Hui; Hu, Tao; Wang, Xiaohui; Li, Zhaojin; Hu, Minmin; Wu, Erdong; Zhou, Yanchun

    2015-01-01

    The conventional wisdom to tailor the properties of binary transition metal carbides by order-disorder phase transformation has been inapplicable for the machinable ternary carbides (MTCs) due to the absence of ordered phase in bulk sample. Here, the presence of an ordered phase with structural carbon vacancies in Nb4AlC3–x (x ≈ 0.3) ternary carbide is predicted by first-principles calculations, and experimentally identified for the first time by transmission electron microscopy and micro-Raman spectroscopy. Consistent with the first-principles prediction, the ordered phase, o-Nb4AlC3, crystalizes in P63/mcm with a = 5.423 Å, c = 24.146 Å. Coexistence of ordered (o-Nb4AlC3) and disordered (Nb4AlC3–x) phase brings about abundant domains with irregular shape in the bulk sample. Both heating and electron irradiation can induce the transformation from o-Nb4AlC3 to Nb4AlC3–x. Our findings may offer substantial insights into the roles of carbon vacancies in the structure stability and order-disorder phase transformation in MTCs. PMID:26388153

  8. Experimental and first-principles investigation of the electronic structure anisotropy of Cr2AlC

    NASA Astrophysics Data System (ADS)

    Bugnet, M.; Jaouen, M.; Mauchamp, V.; Cabioc'h, T.; Hug, G.

    2014-11-01

    The anisotropy of the electronic structure of the MAX phase Cr2AlC has been investigated by electron-energy-loss spectroscopy (EELS) at the C K edge, and x-ray-absorption spectroscopy (XAS) at the Al K , Cr L2 ,3, and Cr K edges. The experimental spectra were interpreted using either a multiple-scattering approach or a full-potential band-structure method. The anisotropy is found to be small around C atoms because of the rather isotropic nature of the octahedral site, and of the averaging of the empty C p states probed by EELS at the C K edge. In turn, a pronounced anisotropy of the charge distribution around Al atoms is evidenced from polarized XAS measurements performed on textured Cr2AlC sputtered thin films. From the analysis of the XAS data using the multiple-scattering feff code, it is demonstrated that the probed thin film is constituted of 70 % (0001) and 30 % (10 1 ¯3 ) grains oriented parallel to the film surface. A decomposition of the calculated spectrum in coordination shells allows for the ability to connect XAS fine structures to the Cr2AlC structure. Combining high-resolution data with up-to-date multiple-scattering calculations, it is shown that the crystalline orientations of the grains present in a probe of 100 ×100 μ m 2 can be determined from the Cr K edge. Interestingly, it is also revealed that a static disorder is involved in the studied thin films. These findings highlight that, given the overall agreement between experimental and calculated spectra, the Cr2AlC electronic structure is accurately predicted using density functional theory.

  9. A high-temperature neutron diffraction study of Nb2AlC and TiNbAlC

    DOE PAGES

    Bentzel, Grady W.; Lane, Nina J.; Vogel, Sven C.; ...

    2014-12-16

    In this paper, we report on the crystal structures of Nb2AlC and TiNbAlC actual composition (Ti0.45,Nb0.55)2AlC compounds determined from Rietveld analysis of neutron diffraction patterns in the 300-1173 K temperature range. The average linear thermal expansion coefficients of a Nb2AlC sample in the a and c directions are, respectively, 7.9(5)x10-6 K-1 and 7.7(5)x10-6 K-1 on one neutron diffractometer and 7.3(3)x10-6 K-1 and 7.0(2)x10-6 K-1 on a second diffractometer. The respective values for the (Ti0.45,Nb0.55)2AlC composition - only tested on one diffractometer - are 8.5(3)x10-6 K-1 and 7.5(5)x10-6 K-1. These values are relatively low compared to other MAX phases. Like othermore » MAX phases, however, the atomic displacement parameters show that the Al atoms vibrate with higher amplitudes than the Ti and C atoms, and 1 more along the basal planes than normal to them. In addition, when the predictions of the atomic displacement parameters obtained from density functional theory are compared to the experimental results, good quantitative agreement is found for the Al atoms. In case of the Nb and C atoms, the agreement was more qualitative.« less

  10. Heavy metal contents of paddy fields of Alcácer do Sal, Portugal.

    PubMed

    Fernandes, J C; Henriques, F S

    1990-01-01

    Recent claims of metal contamination in the lower reaches of the Sado River, in the Alcácer do Sal region, Portugal, a major rice-producing area were investigated by carrying out metal surveys in the area. The elements Fe, Mn, Zn, Cu and Pb were measured in the soil and in rice plant parts--roots, shoots and grain--as well as in some weeds growing in the Sado banks, near the paddy fields. Results showed that the metal contents of paddy soils were similar to background concentrations, with the exception of Zn and Cu, which were above those concentrations and reached their highest levels at Vale de Guizo, the monitored station located furthest upstream in the Sado River. At some sites, plant roots accumulated relatively large amounts of Fe, Mn, Zn and Cu, but the shoot levels of these metals were within the normal range for rice plants. It is possible that varying, but significant, amounts of Fe associated with the roots were in the form of ferric hydroxide plaque covering their surfaces. Copper levels in the shoots of rice were below the normal contents cited for this plant in the literature. Metal levels of river sediments collected near Vale de Guizo seem to corroborate the possibility of some metal contamination in the Sado River, most probably derived from pyrites mining activity in the upper zone of the Sado basin.

  11. Cold spray deposition of Ti2AlC coatings for improved nuclear fuel cladding

    NASA Astrophysics Data System (ADS)

    Maier, Benjamin R.; Garcia-Diaz, Brenda L.; Hauch, Benjamin; Olson, Luke C.; Sindelar, Robert L.; Sridharan, Kumar

    2015-11-01

    Coatings of Ti2AlC MAX phase compound have been successfully deposited on Zircaloy-4 (Zry-4) test flats, with the goal of enhancing the accident tolerance of LWR fuel cladding. Low temperature powder spray process, also known as cold spray, has been used to deposit coatings ∼90 μm in thickness using powder particles of <20 μm. X-ray diffraction analysis showed the phase-content of the deposited coatings to be identical to the powders indicating that no phase transformation or oxidation had occurred during the coating deposition process. The coating exhibited a high hardness of about 800 HK and pin-on-disk wear tests using abrasive ruby ball counter-surface showed the wear resistance of the coating to be significantly superior to the Zry-4 substrate. Scratch tests revealed the coatings to be well-adhered to the Zry-4 substrate. Such mechanical integrity is required for claddings from the standpoint of fretting wear resistance and resisting wear handling and insertion. Air oxidation tests at 700 °C and simulated LOCA tests at 1005 °C in steam environment showed the coatings to be significantly more oxidation resistant compared to Zry-4 suggesting that such coatings can potentially provide accident tolerance to nuclear fuel cladding.

  12. On the small angle twist sub-grain boundaries in Ti3AlC2

    PubMed Central

    Zhang, Hui; Zhang, Chao; Hu, Tao; Zhan, Xun; Wang, Xiaohui; Zhou, Yanchun

    2016-01-01

    Tilt-dominated grain boundaries have been investigated in depth in the deformation of MAX phases. In stark contrast, another important type of grain boundaries, twist grain boundaries, have long been overlooked. Here, we report on the observation of small angle twist sub-grain boundaries in a typical MAX phase Ti3AlC2 compressed at 1200 °C, which comprise hexagonal screw dislocation networks formed by basal dislocation reactions. By first-principles investigations on atomic-scale deformation and general stacking fault energy landscapes, it is unequivocally demonstrated that the twist sub-grain boundaries are most likely located between Al and Ti4f (Ti located at the 4f Wyckoff sites of P63/mmc) layers, with breaking of the weakly bonded Al–Ti4f. The twist angle increases with the increase of deformation and is estimated to be around 0.5° for a deformation of 26%. This work may shed light on sub-grain boundaries of MAX phases, and provide fundamental information for future atomic-scale simulations. PMID:27034075

  13. Oxidation Resistance of Materials Based on Ti3AlC2 Nanolaminate at 600 °C in Air.

    PubMed

    Ivasyshyn, Andrij; Ostash, Orest; Prikhna, Tatiana; Podhurska, Viktoriya; Basyuk, Tatiana

    2016-12-01

    The oxidation behavior of Ti3AlC2-based materials had been investigated at 600 °C in static air for 1000 h. It was shown that the intense increase of weight gain per unit surface area for sintered material with porosity of 22 % attributed to oxidation of the outer surface of the specimen and surfaces of pores in the bulk material. The oxidation kinetics of the hot-pressed Ti3AlC2-based material with 1 % porosity remarkably increased for the first 15 h and then slowly decreased. The weight gain per unit surface area for this material was 1.0 mg/cm(2) after exposition for 1000 h. The intense initial oxidation of Ti3AlC2-based materials can be eliminated by pre-oxidation treatment at 1200 °C in air for 2 h. As a result, the weight gain per unit surface area for the pre-oxidized material did not exceed 0.11 mg/cm(2) after 1000 h of exposition at 600 °C in air. It was demonstrated that the oxidation resistance of Ti3AlC2-based materials can be significantly improved by niobium addition.

  14. Measuring the spectrum of mutation induced by nitrogen ions and protons in the human-hamster hybrid cell line A(L)C

    NASA Technical Reports Server (NTRS)

    Kraemer, S. M.; Kronenberg, A.; Ueno, A.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    2000-01-01

    Astronauts can be exposed to charged particles, including protons, alpha particles and heavier ions, during space flights. Therefore, studying the biological effectiveness of these sparsely and densely ionizing radiations is important to understanding the potential health effects for astronauts. We evaluated the mutagenic effectiveness of sparsely ionizing 55 MeV protons and densely ionizing 32 MeV/nucleon nitrogen ions using cells of two human-hamster cell lines, A(L) and A(L)C. We have previously characterized a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in the human-hamster hybrid cell lines A(L)C and A(L). CD59(-) mutants have lost expression of a human cell surface antigen encoded by the CD59 gene located at 11p13. Deletion of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the A(L) hybrid, so that CD59 mutants that lose the entire chromosome 11 die and escape detection. In contrast, deletion of the 11p15.5 region is not lethal in the hybrid A(L)C, allowing for the detection of chromosome loss or other chromosomal mutations involving 11p15.5. The 55 MeV protons and 32 MeV/nucleon nitrogen ions were each about 10 times more mutagenic per unit dose at the CD59 locus in A(L)C cells than in A(L) cells. In the case of nitrogen ions, the mutations observed in A(L)C cells were predominantly due to chromosome loss events or 11p deletions, often containing a breakpoint in the pericentromeric region. The increase in the CD59(-) mutant fraction for A(L)C cells exposed to protons was associated with either translocation of portions of 11q onto a hamster chromosome, or discontinuous or "skipping" mutations. We demonstrate here that A(L)C cells are a powerful tool that will aid in the understanding of the mutagenic effects of different types of ionizing radiation.

  15. Moose (Alces alces) reacts to high summer temperatures by utilizing thermal shelters in boreal forests - an analysis based on airborne laser scanning of the canopy structure at moose locations.

    PubMed

    Melin, Markus; Matala, Juho; Mehtätalo, Lauri; Tiilikainen, Raisa; Tikkanen, Olli-Pekka; Maltamo, Matti; Pusenius, Jyrki; Packalen, Petteri

    2014-04-01

    The adaptation of different species to warming temperatures has been increasingly studied. Moose (Alces alces) is the largest of the ungulate species occupying the northern latitudes across the globe, and in Finland it is the most important game species. It is very well adapted to severe cold temperatures, but has a relatively low tolerance to warm temperatures. Previous studies have documented changes in habitat use by moose due to high temperatures. In many of these studies, the used areas have been classified according to how much thermal cover they were assumed to offer based on satellite/aerial imagery data. Here, we identified the vegetation structure in the areas used by moose under different thermal conditions. For this purpose, we used airborne laser scanning (ALS) data extracted from the locations of GPS-collared moose. This provided us with detailed information about the relationships between moose and the structure of forests it uses in different thermal conditions and we were therefore able to determine and differentiate between the canopy structures at locations occupied by moose during different thermal conditions. We also discovered a threshold beyond which moose behaviour began to change significantly: as day temperatures began to reach 20 °C and higher, the search for areas with higher and denser canopies during daytime became evident. The difference was clear when compared to habitat use at lower temperatures, and was so strong that it provides supporting evidence to previous studies, suggesting that moose are able to modify their behaviour to cope with high temperatures, but also that the species is likely to be affected by warming climate.

  16. The effect of size and density on the mean retention time of particles in the reticulorumen of cattle ( Bos primigenius f. taurus), muskoxen ( Ovibos moschatus) and moose ( Alces alces).

    PubMed

    Clauss, Marcus; Lechner, Isabel; Barboza, Perry; Collins, William; Tervoort, Theo A; Südekum, Karl-Heinz; Codron, Daryl; Hummel, Jürgen

    2011-02-01

    Particle passage from the reticulorumen (RR) depends on particle density and size. Forage particle density and size are related and change over time in the RR. Particle density mainly influences sorting in the reticulum, whereas particle size influences particle retention in the fibre mat of stratified rumen contents ('filter-bed' effect). We investigated these effects independently, by inserting plastic particles of different sizes (1, 10 and 20 mm) and densities (1·03, 1·20 and 1·44 mg/ml) in the RR of cattle (Bos primigenius f. taurus) as a pilot study, and of muskoxen (Ovibos moschatus; n 4) and moose (Alces alces; n 2) both fed two diets (browse and grass). Faeces were analysed for plastic residues for 13 d after dosing to calculate mean retention times (MRT). The results confirmed previous findings of differences in absolute MRT between species. Comparing muskoxen with moose, there was no difference in the effect of particle density on the MRT between species but particle size had a more pronounced effect on the MRT in muskoxen than in moose. This indicated a stronger 'filter-bed effect' in muskoxen, in accord with the reports of stratified RR contents in this species v. the absence of RR content stratification in moose. Low-density particles were retained longer in both species fed on grass diets, indicating a contribution of forage type to the 'filter-bed effect'. The results indicate that retention based on particle size may differ between ruminant species, depending on the presence of a fibre mat in the RR, whereas the density-dependent mechanism of sedimentation in the RR is rather constant across species.

  17. Relative importance of hydrolyzed Al(III) species (Al(a), Al(b), and Al(c)) during coagulation with polyaluminum chloride: a case study with the typical micro-polluted source waters.

    PubMed

    Yan, Mingquan; Wang, Dongsheng; Qu, Jiuhui; He, Wenjie; Chow, Christopher W K

    2007-12-15

    The relative importance of three different Al species, Al(a) (monomeric species, instantaneous reacted species), Al(b) (medium polymer species, reacted less than 120 min), and Al(c) (colloidal or solid species, no reaction), defined by timed complexation reaction rate measured by using ferron reagent in polyaluminum chloride (PACl) was investigated in terms of DOC (dissolved organic carbon), UV(254), and turbidity removal efficiencies. Micro-polluted, typical North China, source waters were used to conduct the experiments. The results show that DOC removal is correlated well to the content of Al(b). Removal of UV(254) is determined by the content of Al(b) and Al(c), particularly Al(c). Turbidity removal is primarily related to the content of Al(c); however, Al(b) could destabilize particles efficiently, and the flocs formed by Al(b) are not as large as those formed by Al(c), which affected the settling efficiency. Unlike the preformed Al(b), the in situ formed Al(b) could remove turbidity more efficiently since Al(c) is the dominant final species formed during coagulation. Al(a) shows a strong ability to react with some unsatisfied coordinate bonds of organic matter to facilitate particle and DOC removal. The distinct coagulation feature of Al(a), Al(b), and Al(c) can be applied to develop tailor-made PACl (with the correct distribution of Al species) to match the characteristics of raw water for optimized coagulation.

  18. The Cretaceous (Cenomanian) continental record of the Laje do Coringa flagstone (Alcântara Formation), northeastern South America

    NASA Astrophysics Data System (ADS)

    Medeiros, Manuel Alfredo; Lindoso, Rafael Matos; Mendes, Ighor Dienes; Carvalho, Ismar de Souza

    2014-08-01

    The fossil taxa of the Cenomanian continental flora and fauna of São Luís Basin are observed primarily in the bone bed of the Laje do Coringa, Alcântara Formation. Many of the disarticulated fish and tetrapod skeletal and dental elements are remarkably similar to the chronocorrelate fauna of Northern Africa. In this study, we present a summary of the continental flora and fauna of the Laje do Coringa bone-bed. The record emphasizes the existence of a trans-oceanic typical fauna, at least until the early Cenomanian, which may be interpreted as minor evolutionary changes after a major vicariant event or as a result of a land bridge across the equatorial Atlantic Ocean, thereby allowing interchanges between South America and Africa. The paleoenvironmental conditions in the northern Maranhão State coast during that time were inferred as forested humid areas surrounded by an arid to semi-arid landscape.

  19. Anisotropic swelling and microcracking of neutron irradiated Ti3AlC2-Ti5Al2C3 materials

    DOE PAGES

    Ang, Caen K.; Silva, Chinthaka M.; Shih, Chunghao Phillip; ...

    2015-12-17

    Mn + 1AXn (MAX) phase materials based on Ti–Al–C have been irradiated at 400 °C (673 K) with fission neutrons to a fluence of 2 × 1025 n/m2 (E > 0.1 MeV), corresponding to ~ 2 displacements per atom (dpa). We report preliminary results of microcracking in the Al-containing MAX phase, which contained the phases Ti3AlC2 and Ti5Al2C3. Equibiaxial ring-on-ring tests of irradiated coupons showed that samples retained 10% of pre-irradiated strength. Volumetric swelling of up to 4% was observed. Phase analysis and microscopy suggest that anisotropic lattice parameter swelling caused microcracking. Lastly, variants of titanium aluminum carbide may bemore » unsuitable materials for irradiation at light water reactor-relevant temperatures.« less

  20. Chymotrypsins from the deer (Cervidae) family. Isolation, partial characterization and primary-structure studies of chymotrypsins A and B from both moose (Alces alces) and elk (Cervus elaphus) pancreas.

    PubMed Central

    Lindsay, R M; Stevenson, K J

    1976-01-01

    1. An anionic and a cationic chymotrypsin (EC 3.4.21.1) were isolated from the pancreas glands of the moose (Alces alces) and elk (Cervus elaphus). The A and B chymotrypsins from each species were purified to homogeneity by (NH4)2SO4 fractionation, affinity chromatography on 4-phenylbutylamine-Sepharose and ion-exchange chromatography on DEAE- and CM-cellulose. 2. The molecular weight and pH optimum of each chymotrypsin were similar to those of the corresponding ox A and B chymotrypsins. 3. The substrate specificities of the chymotrypsins were investigated by digestion of glucagon and the oxidized B chain of insulin. The primary specificity of each chymotrypsin for aromatic amino acid residues was further established by determining the Km and kcat for the hydrolysis of a number of synthetic amino acid ester substrates. 4. The amino acid composition and total number of residues of moose and elk chymotrypsin A were similar to those of ox chymotrypsin A. An even greater similarity was observed among the B chymotrypsins of the three species. 5. The A chymotrypsins of moose and elk were fragmented to their constituent 'A', 'B' and 'C' polypeptide chains by succinylation (3-carboxypropionylation), reduction and alkylation of the native enzymes. In each case, the two major chains ('B' and 'C') were separated and isolated. By comparison of the amino acid compositions of moose, elk and oxy 'B' and 'C' chains, a greater difference was observed among the three A chymotrypsins than was suggested by the amino acid compositions of the native enzymes alone. 6. Peptides were isolated from the disulphide bridge and active-site regions of the A and B chymotrypsins of moose and elk by diagonal peptide-'mapping' techniques. From the amino acid compositions of the isolated peptides (assuming maximum homology) and from a comparison of diagonal peptide 'maps', there was established a high degree of primary-structure identity among the mooae, elk and ox chymotrypsins. Tentative sequences

  1. [REBEn in the context of the history of Brazilian nursing: the significance of remembering Dr. Glete de Alcântara].

    PubMed

    Mendes, Isabel Amélia Costa; Leite, Joséte Luzia; Leite, Juçara Luzia; Trevizan, Maria Auxiliadora

    2002-01-01

    This is a Social History study which aims at recuperating the professional trajectory of Glete de Alcântara in the Revista Brasileira de Enfermagem/REBEn (Brazilian Journal of Nursing), initially called Anais de Enfermagem. It is based on the concept of memory of Maurice Halbwach, and on the concept of generation of Daniel Pécaut. The study contextualizes the professional development of Glete de Alcântara in the history of the Brazilian nursing, highlighting the creation of the Nursing School of the University of São Paulo (EERP/USP) in Ribeirão Preto. The sources for the study were documents obtained in the Centro de Memória da Escola de Enfermagem (Memory Center of the School of Nursing) of Ribeirão Preto and in ABEN (Brazilian Association of Nursing) in Brasília. Data obtained in this association were mainly collected from its record books the journals.

  2. CUPRI observations of the east-west power asymmetry in oblique type-I echoes from the equatorial electrojet above Alcântara, Brazil

    NASA Astrophysics Data System (ADS)

    Swartz, Wesley E.

    Radar observations of the equatorial electrojet at oblique incidence made by the Cornell University Portable Radar Interferometer (CUPRI) from Alcântara, Brazil show the same east-west asymmetry in the echo strength seen previously at Jicamarca, Peru, namely type-I echoes from the west are stronger than those from the east [Balsley, 1965]. One early theory attributed the results at Jicamarca to topographical asymmetries with the Andes Mountains to the east and the Pacific Ocean to the west [Ierkic et al., 1980]. However, the lack of comparable topographical features at Alcântara now implies that this postulate is no longer tenable. Other proposed theories are then examined, but none has so far been found to be fully consistent with both the CUPRI and the Jicamarca data.

  3. Technology Insertion-Engineering Services Process Characterization Task Order No. 1 (Block II). Database Documentation Book for OC-ALC MABPAB

    DTIC Science & Technology

    1989-09-11

    Sept 89 4. TITLE AND SUBTITLE Technology Insertion (TI) / Industrial 1 5. FUNDING NUMBERS Process Improvement (IPI) Task Order No. (Set1t 1)Cnrc...ABSTRACT (Maximum 200 words) Technology Inser ion (TI)/ Industrial Process Improvement (IPI) Data Base ocumentation Book Volume, for OC-.ALC/MABPAB (Sheet...COPY FURNISHED TO DTIC CONTAINED A SIGNIFICANT NUMBER OF PAGES -WHICH DO NOT REPRODUCE LEGIBLY. TECHNOLOGY INSERTION- ENGINEERING SERVICES PROCESS

  4. Same night observations of spread-F by the Jicamarca Radio Observatory in Peru and CUPRI in Alcântara, Brazil

    NASA Astrophysics Data System (ADS)

    Swartz, Wesley E.; Woodman, Ronald F.

    50-MHz echoes from equatorial spread-F were observed on several nights by both the Jicamarca Radio Observatory (JRO) in Peru and the Cornell University Portable Radar Interferometer (CUPRI) in Alcântara, Brazil. Although little detailed correlation is expected between sites separated by such large distances, the night of October 17, 1994 shows some remarkable similarities between Peru and Brazil. On this night spread-F commenced at both Jicamarca and Alcântara as thin bottomside layers situated near 320 km altitude at nearly the same local times. Later, major plumes erupted that reached to over 1000 km altitude at both sites. Since plumes normally drift west to east, these are obviously not the same structures but the similarities indicate that conditions for spawning them must have been coincidentally very similar on this night. The next two nights which produced plumes over Brazil, but only bottomside layers over Peru, emphasize that local conditions on the same night can be very different at the two locations. The importance of having a sufficiently wide beam for exploring spread-F over a large altitude range at the Alcântara site is also explored.

  5. Positive Family History, Infection, Low Absolute Lymphocyte Count (ALC) and Absent Thymic Shadow: Diagnostic Clues for all Molecular Forms of Severe Combined Immunodeficiency (SCID)

    PubMed Central

    McWilliams, Laurie M; Railey, Mary Dell; Buckley, Rebecca H

    2015-01-01

    Background Severe Combined Immunodeficiency (SCID) is a syndrome uniformly fatal during infancy unless recognized and treated successfully by bone marrow transplantation or gene therapy. Because SCID infants have no abnormal physical appearance, diagnosis is usually delayed unless newborn screening is performed. Objective In this study, we sought to evaluate the presenting features of all 172 SCID patients transplanted at this institution over the past 31 years. Methods We reviewed original charts from 172 consecutive classic SCID patients who received either T cell-depleted HLA-haploidentical (N=154) or HLA-identical (N=18) non-ablative related marrow transplants at Duke University Medical Center from 1982–2013. Results The mean age at presentation was 4.87 months. When there was a family history of early infant death or known SCID (63/172 or 37%), the mean presentation age was much earlier, 2.0 months compared to 6.6 months. Failure to thrive was common, with 84 patients (50%) having a weight less than the 5th percentile. The leading infections included oral moniliasis (43%), viral infections (61/172 35.5%) and Pneumocystis jiroveci (26%) pneumonia. The group mean ALC was 1454/cmm; 88% of the infants had an ALC less than 3000/cmm. Absent thymic shadow was seen in 92% of infants with electronic radiographic data available. An absence of T cell function was found in all patients. Conclusions SCID infants appear normal at birth but later present with failure to thrive and/or recurrent fungal, viral and bacterial infections. Low ALCs and absent thymic shadow on chest x-ray are key diagnostic clues. The absence of T cell function confirms the diagnosis. PMID:25824440

  6. Chromosomal mutations and chromosome loss measured in a new human-hamster hybrid cell line, ALC: studies with colcemid, ultraviolet irradiation, and 137Cs gamma-rays

    NASA Technical Reports Server (NTRS)

    Kraemer, S. M.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    1997-01-01

    Small mutations, megabase deletions, and aneuploidy are involved in carcinogenesis and genetic defects, so it is important to be able to quantify these mutations and understand mechanisms of their creation. We have previously quantified a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in a hamster-human hybrid cell line AL. S1- mutants have lost expression of a human cell surface antigen, S1, which is encoded by the M1C1 gene at 11p13 so that mutants can be detected via a complement-mediated cytotoxicity assay in which S1+ cells are killed and S1- cells survive. But loss of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the AL hybrid, so that mutants that have lost the entire chromosome 11 die and escape detection. To circumvent this, we fused AL with Chinese hamster ovary (CHO) cells to produce a new hybrid, ALC, in which the requirement for maintaining 11p15.5 is relieved, allowing us to detect mutations events involving loss of 11p15.5. We evaluated the usefulness of this hybrid by conducting mutagenesis studies with colcemid, 137Cs gamma-radiation and UV 254 nm light. Colcemid induced 1000 more S1- mutants per unit dose in ALC than in AL; the increase for UV 254 nm light was only two-fold; and the increase for 137Cs gamma-rays was 12-fold. The increase in S1- mutant fraction in ALC cells treated with colcemid and 137Cs gamma-rays were largely due to chromosome loss and 11p deletions often containing a breakpoint within the centromeric region.

  7. Substantiation of Epitaxial Growth of Diamond Crystals on the Surface of Carbide Fe3AlC0.66 Phase Nanoparticles.

    PubMed

    Dzevin, Ievgenij M; Mekhed, Alexander A

    2017-12-01

    Samples of Fe-Al-C alloys of varying composition were synthesized under high pressures and temperatures. From X-ray analysis data, only K-phase with usual for it average parameter of elemental lattice cell, a = 0.376 nm, carbide Fe3C and cubic diamond reflexes were present before and after cooling to the temperature of liquid nitrogen.Calculations were made of the parameters of unit cells, the enthalpy of formation of the Fe3AlC, Fe3.125Al0.825C0.5, Fe3.5Al0.5C0.5, Fe3.5Al0.5C, Fe3Al0.66C0.66, and Fe3AlC0.66 unit cells and crystallographic planes were identified on which epitaxial growth of the diamond phase was possible, using density functional theory as implemented in the WIEN2k package.The possibility of epitaxial growth of diamond crystals on Fe3AlC0.66 (K-phase) nanoparticles was, therefore, demonstrated. The [200] plane was established to be the most suitable plane for diamond growth, having four carbon atoms arranged in a square and a central vacancy which can be occupied by carbon during thermal-and-pressure treatment. Distances between carbon atoms in the [200] plane differ by only 5% from distances between the carbon atoms of a diamond. The electronic structure and energetic parameters of the substrate were also investigated. It was shown that the substrate with at least four intermediate layers of K-phase exhibits signs of stability such as negative enthalpy of formation and the Fermi level falling to minimum densities of states.

  8. Phase Evaluation in Al2O3 Fiber-Reinforced Ti2AlC During Sintering in the 1300 degrees C-1500 degrees C Temperature Range

    DTIC Science & Technology

    2011-01-01

    14—elements, X is either a C and/or N and n = 1,2,3) are a group of nanolayered ternary carbides and nitrides.14 These phases have a hexagonal unit...The only study on fiber-reinforced MAX phases is that of a recent article in which we reinforced Ti2AlC and Ti3SiC2 with SiC fibers and showed that...x,Six)C2 solid solutions.41 The same study, however, showed that SiC fibers can be used to reinforce Ti3SiC2. The purpose of this study was to

  9. Continental fossil vertebrates from the mid-Cretaceous (Albian-Cenomanian) Alcântara Formation, Brazil, and their relationship with contemporaneous faunas from North Africa

    NASA Astrophysics Data System (ADS)

    Candeiro, Carlos Roberto A.; Fanti, Federico; Therrien, François; Lamanna, Matthew C.

    2011-05-01

    The Albian-Cenomanian Alcântara Formation of northeastern Brazil preserves the most diverse continental vertebrate fauna of this age yet known from northern South America. The Alcântara vertebrate assemblage, consisting of elasmobranchs, actinopterygians, sarcopterygians, turtles, crocodyliforms, pterosaurs, and non-avian dinosaurs, displays close similarities to contemporaneous faunas from North Africa. The co-occurrence of as many as eight freshwater or estuarine fish taxa ( Onchopristis, Bartschichthys, Lepidotes, Stephanodus, Mawsonia, Arganodus, Ceratodus africanus, and possibly Ceratodus humei) and up to seven terrestrial archosaur taxa ( Sigilmassasaurus, Rebbachisauridae, Baryonychinae, Spinosaurinae, Carcharodontosauridae, possibly Pholidosauridae, and doubtfully Bahariasaurus) suggests that a land route connecting northeastern Brazil and North Africa existed at least until the Albian. Interestingly, most components of this mid-Cretaceous northern South American/North African assemblage are not shared with coeval southern South American faunas, which are themselves characterized by a number of distinct freshwater and terrestrial vertebrate taxa (e.g., chelid turtles, megaraptoran and unenlagiine theropods). These results suggest that, although mid-Cretaceous faunal interchange was probably possible between northern South America and North Africa, paleogeographic, paleoclimatic, and/or paleoenvironmental barriers may have hindered continental vertebrate dispersal between northern and southern South America during this time.

  10. Taenia arctos n. sp. (Cestoda: Cyclophyllidea: Taeniidae) from its definitive (brown bear Ursus arctos Linnaeus) and intermediate (moose/elk Alces spp.) hosts.

    PubMed

    Haukisalmi, Voitto; Lavikainen, Antti; Laaksonen, Sauli; Meri, Seppo

    2011-11-01

    Taenia arctos n. sp. (Cestoda: Cyclophyllidea: Taeniidae) is described from the brown bear Ursus arctos Linnaeus (definitive host) and moose/elk Alces spp. (intermediate hosts) from Finland (type-locality) and Alaska, USA. The independent status of the new species and the conspecificity of its adults and metacestodes have been recently confirmed by the mtDNA sequence data of Lavikainen et al. (2011; Parasitology International, 60, 289-295). Special reference is given to morphological differences between the new species and T. krabbei Moniez, 1879 (definitive hosts primarily canines for the latter), both of which use the moose/elk (Alces spp.) as intermediate hosts (the latter also uses Rangifer and perhaps other northern ruminants), and between the new species and T. ursina Linstow, 1893, both of which use the brown bear U. arctos as a definitive host. New morphological data are also provided for adults and cysticerci of T. krabbei. The analysis includes potentially useful morphometric features that have not been previously applied to Taenia spp.

  11. V OLATILEC ALC: a silicate melt-H 2O-CO 2 solution model written in Visual Basic for excel

    NASA Astrophysics Data System (ADS)

    Newman, Sally; Lowenstern, Jacob B.

    2002-06-01

    We present solution models for the rhyolite-H 2O-CO 2 and basalt-H 2O-CO 2 systems at magmatic temperatures and pressures below ˜5000 bar. The models are coded as macros written in Visual Basic for Applications, for use within Microsoft ® Excel (Office'98 and 2000). The series of macros, entitled V OLATILEC ALC, can calculate the following: (1) Saturation pressures for silicate melt of known dissolved H 2O and CO 2 concentrations and the corresponding equilibrium vapor composition; (2) open- and closed-system degassing paths (melt and vapor composition) for depressurizing rhyolitic and basaltic melts; (3) isobaric solubility curves for rhyolitic and basaltic melts; (4) isoplethic solubility curves (constant vapor composition) for rhyolitic and basaltic melts; (5) polybaric solubility curves for the two end members and (6) end member fugacities of H 2O and CO 2 vapors at magmatic temperatures. The basalt-H 2O-CO 2 macros in V OLATILEC ALC are capable of calculating melt-vapor solubility over a range of silicate-melt compositions by using the relationships provided by Dixon (American Mineralogist 82 (1997) 368). The output agrees well with the published solution models and experimental data for silicate melt-vapor systems for pressures below 5000 bar.

  12. CUPRI observations of persistence asymmetry reversals in up-down vertical type-I echoes from the equatorial electro jet above Alcântara, Brazil

    NASA Astrophysics Data System (ADS)

    Swartz, Wesley E.

    High resolution vertical radar measurements of the equatorial electrojet above Alcântara, Brazil, were made with the Cornell University Portable Radar Interferometer (CUPRI) as part of the Guará Dip Equator Campaign. Type-I spectra obtained from the main body of the electrojet during strong daytime conditions show a preponderance of upward phase velocities as a function of time. However, the data from a few kilometers higher show a persistence of downward phase velocities. This reversal in sign of the most persistent type-I peak occurs regularly in our data whenever the electrojet is strongly driven. The persistence of upward phase velocities is similar to that seen earlier at Jicamarca but the reversal in sign of the dominating mode has not been previously observed, nor is it consistent with current electrojet theories. Another unexpected result from the Alcântara data set is that the absolute values of the phase velocities of the type-I spectra peaks decrease with altitude. This is through a region where the temperature (and hence the acoustic velocity) should be increasing with altitude. Hence, the saturation of the type-I peak phase velocities is not just a simple function of the acoustic velocity.

  13. Long-term corrosion tests of Ti3SiC2 and Ti2AlC in oxygen containing LBE at temperatures up to 700 °C

    NASA Astrophysics Data System (ADS)

    Heinzel, A.; Weisenburger, A.; Müller, G.

    2016-12-01

    Two MAX-phase materials, Ti3SiC and Ti2AlC, were tested at 550 °C, 650 °C and 700 °C up to 10 000 h in LBE (lead-bismuth-eutectic) containing of 10-6 and 10-8 wt% oxygen. It was found that secondary phases have a strong influence on corrosion effects. Ti3SiC showed a surface disintegration at 550°C/10-6 wt% oxygen after longer exposure, while a 4-7 μm thick TiO2 layer with Pb-Bi inclusions was detected on Ti2AlC. However, Ti3SiC is protected by a double layered oxide with an outer part of TiO2 and a mixed inner layer of SiO2 and TiO2 at the higher temperatures. Ti2AlC formed a TiO2 surface layer containing Al2O3. Some defects could be observed on the Ti3SiC surface in LBE containing 10-8 wt% oxygen at 550 °C and 650 °C. The secondary phases between the Ti3SiC grains showed strong oxidation at 700 °C. Due to the high Al solubility in LBE, Ti2AlC experienced strong dissolution attack after longer exposure times at 650 and 700 °C.

  14. Effects of neutron irradiation of Ti3SiC2 and Ti3AlC2 in the 121-1085 °C temperature range

    NASA Astrophysics Data System (ADS)

    Tallman, Darin J.; He, Lingfeng; Gan, Jian; Caspi, El'ad N.; Hoffman, Elizabeth N.; Barsoum, Michel W.

    2017-02-01

    Herein we report on the formation of defects in response to neutron irradiation of polycrystalline Ti3SiC2 and Ti3AlC2 samples exposed to total fluences of ≈6 × 1020 n/m2, 5 × 1021 n/m2 and 1.7 × 1022 n/m2 at irradiation temperatures of 121(12), 735(6) and 1085(68)°C. These fluences correspond to 0.14, 1.6 and 3.4 dpa, respectively. After irradiation to 0.14 dpa at 121 °C and 735 °C, black spots are observed via transmission electron microscopy in both Ti3SiC2 and Ti3AlC2. After irradiation to 1.6 and 3.4 dpa at 735 °C, basal dislocation loops, with a Burgers vector of b = ½ [0001] are observed in Ti3SiC2, with loop diameters of 21(6) and 30(8) nm after 1.6 dpa and 3.4 dpa, respectively. In Ti3AlC2, larger dislocation loops, 75(34) nm in diameter are observed after 3.4 dpa at 735 °C, in addition to stacking faults. Impurity particles of TiC, as well as stacking fault TiC platelets in the MAX phases, are seen to form extensive dislocation loops under all conditions. Cavities were observed at grain boundaries and within stacking faults after 3.4 dpa irradiation, with extensive cavity formation in the TiC regions at 1085 °C. Remarkably, denuded zones on the order of 1 μm are observed in Ti3SiC2 after irradiation to 3.4 dpa at 735 °C. Small grains, 3-5 μm in diameter, are damage free after irradiation at 1085 °C at this dose. The results shown herein confirm once again that the presence of the A-layers in the MAX phases considerably enhance their irradiation tolerance. Based on these results, and up to 3.4 dpa, Ti3SiC2 remains a promising candidate for high temperature nuclear applications as long as the temperature remains >700 °C.

  15. Technology Insertion (TI)/Industrial Process Improvement (IPI) Task Order Number 1. Data Base Documentation Book for SA-ALC/MATPSS (Assembly and Test GTE’s)

    DTIC Science & Technology

    1989-08-14

    8217 -- - AD-A237 070 JMENTATION PAGE _ N tt t *. 0 ’t o0t o f im lt0 e o mn’t0 tfverage Itott I ( flh t Ett 9 ain q ’ tc "I"? O" 3t W turce* i i...technology Insertion (TI)/Industrial Process Improvement (IPI).D(taas%V’ocumentatioh ,ook Folume-; f or SA-ALC/MATPSS (Assembl’V & Test GTE’s X . this...ffo6A Fir W~ r-uFL sTAgTFR &FEs) 13e r14 JET FUE STRT~ER (jFS) c! ?6O7A ,F15 (&/FI-RAL 6-iARt9,-; X k/6rR )27I2A F/ ACcfKS~tQR VR,]F (,FARBcX (At&-) Od

  16. CUPRI observations of pre-sunrise vertical type-I echoes from the equatorial electrojet above Alcântara, Brazil

    NASA Astrophysics Data System (ADS)

    Swartz, Wesley E.

    1997-10-01

    The Cornell University Portable Radar Interferometer (CUPRI) made high resolution vertical radar measurements of the equatorial electrojet above Alcântara, Brazil from mid-August to mid-October, 1994, as part of the Guará Dip Equator Campaign. Spectra obtained during the period of a few hours before sunrise show the usual nighttime persistence asymmetry wherein there is a preponderance of downward type-I phase velocities as a function of time. These are the first high resolution measurements in South America of this effect at a location other than Jicamarca, Peru. Furthermore the CUPRI interferometer phase data clearly indicate that when changes in the sign of the dominate type-I peaks occur, they are tied to the normal phase progressions of the large scale waves. No reversal of the asymmetry (as does occur in the daytime) was seen in this nighttime period.

  17. Structure par RMN d'un complexe AlcR(1-60)-ADN: Reconnaissance du petit sillon par la partie N-terminale

    NASA Astrophysics Data System (ADS)

    Cahuzac, B.; Félenbok, B.; Guittet, E.

    1999-10-01

    Aspergillus nidulans is a filamentous fungus able to use ethanol as sole energy source. The activation of the ethanol regulon genes expression is mediated by the AlcR protein. Its DNA-binding domain is located in the N-terminus (residues 1 to 60), and its NMR solution structure shows a global zinc binuclear cluster fold, with two helices in addition to the basic binuclear motif. A small number of crystallographic structures of DNA complexes of binuclear cluster proteins is yet known, and points out the major groove and the first helix as the principal sites of interaction on the DNA and the protein respectively. In this article we show evidences that the N-terminus of the protein is involved in binding to the minor groove. Aspergillus nidulans est un champignon filamenteux capable d'utiliser l'éthanol comme source unique d'énergie. La protéine AlcR est responsable de l'activation de l'expression des gènes du régulon éthanol. Le domaine de liaison à l'ADN est situé dans la partie N-terminale de la protéine (a.a. 1 à 60), et sa structure déterminée par RMN en solution montre un repliement global en bouquet binucléaire à zinc, avec deux hélices supplémentaires par rapport au motif de base. Alors que les structures déjà connues de complexes ADN - bouquets binucléaires permettent de situer dans le grand sillon la quasi-totalité des interactions, nous montrons dans la présente étude l'implication du début de la séquence dans la reconnaissance du petit sillon de l'ADN (a.a. 5 et 6).

  18. H Ly-alpha transmittance of thin foils of C, Si/C, and Al/C for keV particle detectors

    NASA Technical Reports Server (NTRS)

    Drake, V. A.; Sandel, B. R.; Jenkins, D. G.; Hsieh, K. C.

    1992-01-01

    A class of instruments designed for remote sensing of space plasmas by measuring energetic neutral atoms (ENA) uses a thin foil as both a signal generator and a light shield. An ENA imager must look directly at the ENA source region, which is also usually an intense source of H Ly-alpha (1216 A) photons. It is desirable to minimize the energy threshold for ENA detectors, at the same time maximizing the blocking of H Ly-alpha. Optimizing filter design to meet these two contrary requirements has led us to measure the transmittance of thin C, Si/C, and Al/C foils at H Ly-alpha. Our results indicate that (1) transmittance of less than 0.0007 can be achieved with 7 micro-g/sq cm Si on 1.7 micro-g/sq cm C; (2) an Si/C composite foil with a thin carbon layer is more effective in blocking UV radiation while having the lowest energy threshold of all the foils measured; and (3) transmittance of Si/C foils of known Si and C thicknesses cannot be accurately predicted, but must be measured.

  19. White-tailed deer (Odocoileus virginianus) subsidize gray wolves (Canis lupus) during a moose (Alces americanus) decline: A case of apparent competition?

    USGS Publications Warehouse

    Barber-Meyer, Shannon; Mech, L. David

    2016-01-01

    Moose (Alces americanus) in northeastern Minnesota have declined by 55% since 2006. Although the cause is unresolved, some studies have suggested that Gray Wolves (Canis lupus) contributed to the decline. After the Moose decline, wolves could either decline or switch prey. To determine which occurred in our study area, we compared winter wolf counts and summer diet before and after the Moose decline. While wolf numbers in our study area nearly doubled from 23 in winter 2002 to an average of 41 during winters 2011–2013, calf:cow ratios (the number of calves per cow observed during winter surveys) in the wider Moose range more than halved from 0.93 in 2002 to an average of 0.31 during 2011–2013. Compared to summer 2002, wolves in summers 2011–2013 consumed fewer Moose and more White-tailed Deer (Odocoileus virginianus). While deer densities were similar during each period, average vulnerability, as reflected by winter severity, was greater during 2011–2013 than 2002, probably explaining the wolf increase. During the wolf increase Moose calves remained a summer food item. These findings suggest that in part of the Moose range, deer subsidized wolf numbers while wolves also preyed on Moose calves. This contributed to a Moose decline and is a possible case of apparent competition and inverse-density-dependent predation.

  20. cDNA and derived amino acid sequence of ethanol-inducible rabbit liver cytochrome P-450 isozyme 3a (P-450ALC).

    PubMed Central

    Khani, S C; Zaphiropoulos, P G; Fujita, V S; Porter, T D; Koop, D R; Coon, M J

    1987-01-01

    Administration of ethanol to rabbits is known to induce a unique liver microsomal cytochrome P-450, termed isozyme 3a or P-450ALC, which is responsible for the increased oxidation of ethanol and other alcohols and the activation of toxic or carcinogenic compounds such as acetaminophen and N-nitrosodimethylamine. To further characterize this cytochrome P-450 we have identified cDNA clones to isozyme 3a by immunoscreening, DNA hybridization, and hybridization-selection. The cDNA sequence determined from two overlapping clones contains an open reading frame of 1416 nucleotides, and the first 25 amino acids of this reading frame correspond to residues 21-45 of cytochrome P-450 3a. The complete polypeptide, including residues 1 to 20, contains 492 amino acids and has a molecular weight of 56,820. Cytochrome P-450 3a is approximately 55% identical in sequence to P-450 isozymes 1 and 3b and 48% identical to isozyme 2. Hybridization of clone p3a-2 to electrophoretically fractionated rabbit liver poly(A)+ RNA revealed multiple bands, but, with a probe derived from the 3' nontranslated portion of this cDNA, only a 1.9-kilobase band was observed. Treatment of rabbits with imidazole, which increases the content of isozyme 3a, resulted in a transient increase in form 3a mRNA, but this was judged to be insufficient to account for the known 4.5-fold increase in form 3a protein. Genomic DNA analysis indicated that the cytochrome P-450 3a gene does not belong to a large subfamily. Images PMID:3027695

  1. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus)

    PubMed Central

    Wong, Mabel T.; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A.; Master, Emma R.

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

  2. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

    PubMed

    Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

  3. Perceptions of environmental change and use of traditional knowledge to plan riparian forest restoration with relocated communities in Alcântara, Eastern Amazon

    PubMed Central

    2014-01-01

    Background Riparian forests provide ecosystem services that are essential for human well-being. The Pepital River is the main water supply for Alcântara (Brazil) and its forests are disappearing. This is affecting water volume and distribution in the region. Promoting forest restoration is imperative. In deprived regions, restoration success depends on the integration of ecology, livelihoods and traditional knowledge (TEK). In this study, an interdisciplinary research framework is proposed to design riparian forest restoration strategies based on ecological data, TEK and social needs. Methods This study takes place in a region presenting a complex history of human relocation and land tenure. Local populations from seven villages were surveyed to document livelihood (including ‘free-listing’ of agricultural crops and homegarden tree species). Additionally, their perceptions toward environmental changes were explored through semi-structured interviews (n = 79). Ethnobotanical information on forest species and their uses were assessed by local-specialists (n = 19). Remnants of conserved forests were surveyed to access ecological information on tree species (three plots of 1,000 m2). Results included descriptive statistics, frequency and Smith’s index of salience of the free-list results. Results The local population depends primarily on slash-and-burn subsistence agriculture to meet their needs. Interviewees showed a strong empirical knowledge about the environmental problems of the river, and of their causes, consequences and potential solutions. Twenty-four tree species (dbh > 10 cm) were found at the reference sites. Tree density averaged 510 individuals per hectare (stdv = 91.6); and 12 species were considered the most abundant (density > 10ind/ha). There was a strong consensus among plant-specialists about the most important trees. The species lists from reference sites and plant-specialists presented an important convergence

  4. Internal architecture of mixed tide- and storm-influenced deposits: an example from the Alcántara Formation, northern Brazil

    NASA Astrophysics Data System (ADS)

    de Fátima Rossetti, Dilce

    1997-12-01

    The uppermost portion of the Itapecuru Group is exposed in the eastern margin of the Sao Luis Basin, northern Brazil, where it consists of two units: the Alcantara Formation (Cenomanian) and the Cujupe Formation (Late Cretaceous-early Tertiary? [Rossetti, D.F., Truckenbrodt, W., 1997. Revisão estratigrdfica para os depósitos do Albiano-Terciário Inferior (?) na Bacia de Sao Luis (MA), norte do Brasil. Bol. Mus. Paraense Emílio Goeldi (Sér. Ciênc. Terra), in press]). The Alcântara Formation, which contains the large-scale structures discussed in this paper, consists of deposits attributed to mid- to upper-shoreface, foreshore, tidal channel, and lagoon/washover environments attributed to a regressive, barred shoreline. Several types of large-scale cross bedding (i.e., simple foreset, compound, mixed, undulatory, and intricately bounded) were recognized in the shoreface facies association. These structures are interpreted to record the interaction of storm and tidal processes. The storm influence is suggested by a combination of factors, mostly including: (a) the genetic association with other storm-generated sedimentary structures (i.e., swaley cross stratification and undulating parallel lamination with internal truncations); (b) the deposition on prominent surfaces formed by storm erosion, which are defined by large-scale, either symmetrical or asymmetrical scours arranged in a regular, repeating pattern; (c) the sedimentary features formed under combined (unidirectional and oscillatory) flow processes (e.g., compound/mixed bedding with superimposed either swaley cross sets or complexly truncating cross sets with highly undulating boundaries; large-scale, undulatory and intricately bounded cross beddings); and (d) the lateral change in structural styles within short distances, which records frequent modification from asymmetrical to symmetrical/nearly symmetrical bedform profiles (more likely to occur under storm-generated combined flows). The tidal

  5. Hyperfine rather than spin splittings dominate the fine structure of the B {sup 4}Σ{sup −}–X {sup 4}Σ{sup −} bands of AlC

    SciTech Connect

    Clouthier, Dennis J. Kalume, Aimable

    2016-01-21

    Laser-induced fluorescence and wavelength resolved emission spectra of the B {sup 4}Σ{sup −}–X {sup 4}Σ{sup −} band system of the gas phase cold aluminum carbide free radical have been obtained using the pulsed discharge jet technique. The radical was produced by electron bombardment of a precursor mixture of trimethylaluminum in high pressure argon. High resolution spectra show that each rotational line of the 0-0 and 1-1 bands of AlC is split into at least three components, with very similar splittings and intensities in both the P- and R-branches. The observed structure was reproduced by assuming b{sub βS} magnetic hyperfine coupling in the excited state, due to a substantial Fermi contact interaction of the unpaired electron in the aluminum 3s orbital. Rotational analysis has yielded ground and excited state equilibrium bond lengths in good agreement with the literature and our own ab initio values. Small discrepancies in the calculated intensities of the hyperfine lines suggest that the upper state spin-spin constant λ′ is of the order of ≈0.025–0.030 cm{sup −1}.

  6. A critical evaluation of GGA + U modeling for atomic, electronic and magnetic structure of Cr2AlC, Cr2GaC and Cr2GeC.

    PubMed

    Dahlqvist, M; Alling, B; Rosen, J

    2015-03-11

    In this work we critically evaluate methods for treating electron correlation effects in multicomponent carbides using a GGA + U framework, addressing doubts from previous works on the usability of density functional theory in the design of magnetic MAX phases. We have studied the influence of the Hubbard U-parameter, applied to Cr 3d orbitals, on the calculated lattice parameters, magnetic moments, magnetic order, bulk modulus and electronic density of states of Cr2AlC, Cr2GaC and Cr2GeC. By considering non-, ferro-, and five different antiferromagnetic spin configurations, we show the importance of including a broad range of magnetic orders in the search for MAX phases with finite magnetic moments in the ground state. We show that when electron correlation is treated on the level of the generalized gradient approximation (U = 0 eV), the magnetic ground state of Cr2AC (A = Al, Ga, Ge) is in-plane antiferromagnetic with finite Cr local moments, and calculated lattice parameters and bulk modulus close to experimentally reported values. By comparing GGA and GGA + U results with experimental data we find that using a U-value larger than 1 eV results in structural parameters deviating strongly from experimentally observed values. Comparisons are also done with hybrid functional calculations (HSE06) resulting in an exchange splitting larger than what is obtained for a U-value of 2 eV. Our results suggest caution and that investigations need to involve several different magnetic orders before lack of magnetism in calculations are blamed on the exchange-correlation approximations in this class of magnetic MAX phases.

  7. Sarcocystis species in moose (Alces alces), bison (Bison, bison), and pronghorn (Antilocapra americana) in Montana.

    PubMed

    Dubey, J P

    1980-12-01

    The transmission of Sarcocystis spp from naturally infected moose, bison, and pronghorn was attempted in laboratory-raised coyotes and dogs. Infected musculature from a moose was feed to a dog and a coyote, and 12 days later, both animals shed sporocysts. Sporocysts were 14 to 17 X 8.5 to 10.5 micron (av 14.5 X 8.8). A coyote was fed muscle from a bison, and 11 days later, it shed sporocysts. The sporocysts were 14 to 16 X 9 to 11 micron (14.0 X 9.0). Infected tissues from a pronghorn were fed to a dog; the dog did not shed sporocysts. Two morphologically distinct sarcocysts (thick walled and thin walled) were found in masculature of a moose. The name, Sarcocystis alceslatrans, sp n, is proposed for the thin-walled sarcocysts in the mouse.

  8. Assessing and modeling moose (Alces alces) habitats with airborne laser scanning data

    NASA Astrophysics Data System (ADS)

    Melin, M.; Packalén, P.; Matala, J.; Mehtätalo, L.; Pusenius, J.

    2013-08-01

    In the analysis of forest resources, the use of ALS (airborne laser scanning) enables detailed three dimensional (3D) descriptions of forests and their vegetation. Simultaneously, ecologists have recognized that 3D information on vegetation is highly important in analyzing the habitat suitability of a given site. Recently, animals’ habitat preferences have been analyzed, for example, with GPS-collared animals. This has resulted in detailed knowledge about the animals’ movements both spatially and temporally. This study combines 3D information on vegetation obtained from ALS data with information about animal locations from GPS data. The aim was to map and analyze the habitat preferences of moose. The study area was located on the west coast of Finland. The data consisted of 18 GPS-collared moose (monitored from 2009 to 2010) and ALS data collected in 2010. We investigated how habitat structure changes as a function of distance to observed moose locations and how observed moose locations differ from randomly selected locations in terms of 3D structure. We also created a model-based habitat suitability map and tested it against moose occurrences. The results suggested that there are clear differences between the areas occupied and not occupied by moose and that these differences can be detected from ALS data. More importantly, ALS proved its potential in linking 3D descriptions of vegetation directly to observed moose locations without any proxy variables. These observations strongly support future studies.

  9. Chemical and structural composition of Atlantic Canadian moose (Alces alces) incisors with patterns of high breakage.

    PubMed

    MacKenzie, Cynthia S Kendall; Clough, Michael J; Broders, Hugh G; Tubrett, Mike

    2011-11-15

    Analysis of mammalian teeth can provide information regarding local environmental conditions. For example, a high incidence of breakage and wear within a population may indicate poor food quality. Individuals consuming a diet causing high mechanical stress on their teeth, and/or lacking the appropriate minerals for proper development, could experience degradation of tooth condition. Previously, we documented a high rate of incisor tooth breakage, with age, in two genetically distinct moose populations in Atlantic Canada. In this study, multi-element (11B, 63Cu, 64Zn, 75As, 85Rb, 88Sr, 111Cd, 118Sn, 137Ba, 208Pb, 232Th, and 238U) analyses using laser ablation ICP-MS were performed on moose incisors from multiple North American regions. The purpose was to determine whether the elemental composition of moose incisors varies among regions, and whether that variation is related to tooth degradation among Atlantic Canadian populations. A principal components analysis revealed that nearly 50% of the elemental variation in the inner enamel matrix of moose teeth was explained by three groupings of elements. The element groupings revealed differences among geographic regions, but did not explain the variation between incisors that were broken and those that were not. Regression models indicate that the elemental group which includes Cu, Pb, and Zn is related to decreases in incisal integrity. It is likely that other environmental factors contribute to the occurrence of increased incisor breakage in affected populations. The relationship between food resource quantity and quality, as a function of moose density, is hypothesized to explain loss of tooth integrity.

  10. Endoparasites in a Norwegian moose (Alces alces) population - Faunal diversity, abundance and body condition.

    PubMed

    Davidson, Rebecca K; Ličina, Tina; Gorini, Lucrezia; Milner, Jos M

    2015-04-01

    Many health surveillance programs for wild cervids do not include routine parasite screening despite evidence that gastrointestinal parasites can affect wildlife population dynamics by influencing host fecundity and survival. Slaughter weights of moose in some regions of Norway have been decreasing over recent decades but any role of parasites has not yet been considered. We investigated parasite faunal diversity of moose in Hedmark, SE Norway, by faecal analysis and identification of adult abomasal and caecal nematodes during the autumn hunting season. We related parasite prevalence and abundance to estimates of body condition, gender and age. We identified 11 parasite groups. Moose had high abomasal gastrointestinal nematode (GIN) burdens and all individuals were infected. Ostertagia antipini and Spiculopteragia alcis were the most prevalent abomasal GINs identified. O. leptospicularis and Telodorsagia circumcincta were also identified in the abomasa while a range of other GIN and Moniezia sp. eggs, and coccidia, Dictyocaulus sp. and Protostrongylid larvae were found in faeces. Female moose had higher mean abomasal nematode counts than males, particularly among adults. However, adult males had higher faecal egg counts than adult females which may reflect reduction in faecal volume with concentration of eggs among males during the rut. We found no strong evidence for the development of acquired immunity to abomasal nematodes with age, although there was a higher Protostrongylid and Moniezia infection prevalence in younger animals. High burdens of several parasites were associated with poor body condition in terms of slaughter weight relative to skeletal size but unrelated to visually evaluated fat reserves. Given findings from earlier experimental studies, our results imply sub-clinical effects of GI parasite infection on host condition. Managers should be aware that autumn faecal egg counts and field assessments of fat reserves may not be reliable indicators of parasitism and may underestimate impacts on wildlife populations.

  11. Impact of the Phase 2 Infantry Advanced Leader Course (ALC)

    DTIC Science & Technology

    2012-07-01

    Transfer of Training: Background and Definition .....................................................................3 Training Transfer Model...Transfer of Training: Background and Definition Effective training has the potential to increase knowledge, skills, and abilities (KSAs) and to enable...agreeableness, extraversion and emotional stability (see Burke & Hutchins, 2007; Blume et al., 2010). Of the “Big Five” personality dimensions

  12. Automatic Loudspeaker Control (ALC). A Summary of Development and Design.

    DTIC Science & Technology

    1989-01-01

    DeJnuryg98 Wahigtn ACU20362&) 4. CNRAER O PAESUSE~ a4 MO IORING AGEANCZA I NA E A ADDR RESSI dill PROGrn’ C nrlin lt. I. S C RITY CL ASSNT RO JE T th p T AS...opae Cotptsing Onfi pce s 15 EUIYA, o isportly S. r in aITIUINd pAnnedN syteo epmet this reportas rvdsalsigo L ouet vial fpro e NoC andli lapp e...for easy probing. The power supply and transformer are connected to the printed circuit board at P3 and P ,,, re- spectively, by connector terminated

  13. Necropsy findings in 62 opportunistically collected free-ranging moose (Alces alces) from Minnesota, USA (2003-13).

    PubMed

    Wünschmann, Arno; Armien, Anibal G; Butler, Erika; Schrage, Mike; Stromberg, Bert; Bender, Jeff B; Firshman, Anna M; Carstensen, Michelle

    2015-01-01

    The Minnesota, US moose population has declined dramatically since the 1990s. All 54 carcasses of moose that died of unknown cause or were euthanized by gun shot by tribal or Department of Natural Resources personnel because of perceived signs of illness between 2003 and 2013 and eight carcasses of moose that died from vehicular accidents between 2009 and 2013 were submitted to the Minnesota Veterinary Diagnostic Laboratory and included in our study. The majority of the animals were underweight or cachectic (n = 53; 85%). Neural migration presumably by Parelaphostrongylus tenuis was a common finding (n = 28; 45%). Moderate to marked Dermacentor albipictus ("winter tick") ectoparasitism with widespread alopecia was the cause or a contributing cause of death in 14 (23%) cases in which grossly apparent anemia was associated with exhaustion of hepatic iron stores. Hepatic lesions associated with Fascioloides magna were common (n = 37; 60%) but were unlikely to be the cause of death. Environmental factors favoring winter tick survival, habitat expansion of white-tailed deer (Odocoileus virginianus), and the survival of terrestrial and aquatic snails (serving as intermediate hosts for P. tenuis and F. magna), might contribute to the seemingly severe parasitic burden in Minnesota's moose population.

  14. The first detection of nematodes Ashworthius sidemi in elk Alces alces (L.) in Poland and remarks of ashworthiosis foci limitations.

    PubMed

    Demiaszkiewicz, Aleksander W; Kuligowska, Izabela; Lachowicz, Jacek; Pyziel, Anna M; Moskwa, Bożena

    2013-12-01

    Ashworthius sidemi, a nematode belonging to the family of Trichostrongylidae, is a primary parasite of the Asian deer, mainly sika deer (Cervus nippon), with which it was introduced to Ukraine, as well as Slovakia, the Czech Republic and France. Migrating red deer carried this parasite from neighboring countries to Polish territory. Until now, in Poland, this parasite has been recorded in European bison, red deer, roe deer and fallow deer. As a result of post-mortem examinations of 10 elk, 2 of them from the Augustów Forest and Biebrza Marshes, A. sidemi were found in abomasa for the first time in Poland. The intensity of the invasions was 120 and 7 specimens, respectively. This finding of Ashworthius sidemi in elk indicates a further expansion of the focus of ashworthiosis in BiaŁowieża towards the north into the Biebrza Marshes and the Augustowska Forest. The growth of the elk population and their tendency for long distance migrations can contribute to the spread of the parasitosis in much greater distances than deer. On the basis of our own research and data from the literature, the current spread of ashworthiosis in Poland is discussed.

  15. The Content of Copper and Molybdenum in the Liver, Kidneys, and Skeletal Muscles of Elk (Alces alces) from North-Eastern Poland.

    PubMed

    Skibniewski, Michał; Skibniewska, Ewa M; Kośla, Tadeusz; Olbrych, Katarzyna

    2016-02-01

    The aim of the study was to evaluate the content of Cu and Mo in the liver, kidneys, and skeletal muscles of elks from north-eastern Poland. The investigation material comprised samples obtained in 2010 from 35 animals. Animals were grouped according to age (elks up to 2 years and over than 3 years). The metal concentrations were determined using coupled plasma-mass spectrometry (ICP-MS) method. The mean Cu concentrations in the liver, kidneys, and skeletal muscles were 23.08, 5.03, and 2.36 mg∙kg(-1) wet weight, respectively. The mean Mo content in the examined samples was as follows: 0.92, 0.42, and 0.05 mg∙kg(-1) wet weight (w.w.) in the liver, kidneys, and muscles. In the analysis of correlation between the Cu and Mo levels in particular organs, the presence of significant dependence (p ≤ 0.05) was observed in the liver of animals studied. The mean Cu content in the liver of animals studied is lower compared with data reported from Sweden, Russia, and North America. Concentrations of Cu and Mo in the kidneys and skeletal muscles of Polish elks are similar to data noted in healthy animals from Scandinavian region. The results suggest that elks from north-eastern Poland may be threatened by primary Cu deficiency.

  16. Physical characteristics of rumen contents in four large ruminants of different feeding type, the addax (Addax nasomaculatus), bison (Bison bison), red deer (Cervus elaphus) and moose (Alces alces).

    PubMed

    Clauss, Marcus; Fritz, Julia; Bayer, Dorothee; Nygren, Kaarlo; Hammer, Sven; Hatt, Jean-Michel; Südekum, Karl-Heinz; Hummel, Jürgen

    2009-03-01

    Based on morphological and physiological observations, it has been suggested that differences exist in the degree that reticuloruminal (RR) contents are stratified between various ruminant species. However, the occurrence of stratification has hardly been measured in non-domestic species. Forestomach contents of free-ranging moose (n=22) and red deer (24) shot during regular hunting procedures, and of captive (but 100% forage fed) addax (6) and bison (10) culled for commercial or management purposes were investigated. There was no difference between the species in the degree by which RR ingesta separated according to size due to buoyancy characteristics in vitro. However, RR fluid of moose was more viscous than that of the other species, and no difference in moisture content was evident between the dorsal and the ventral rumen in moose, in contrast to the other species. Hence, the RR milieu in moose appears less favourable for gas or particle separation due to buoyancy characteristics. These findings are in accord with notable differences in RR papillation between the species. In moose, particle separation is most likely restricted to the reticulum, whereas in the other species, the whole rumen may pre-sort particles in varying degrees; a possible explanation for this pattern is a hypothetically lesser saliva production and fluid throughput in moose. The results suggest that differences in RR physiology may occur across ruminant species. The RR sorting mechanism should be considered a dynamic process that is better measured by its result--the significantly smaller particle size in the distal digestive tract when compared to the RR--than by regional differences in particle size within the RR.

  17. Complex patterns of population genetic structure of moose, Alces alces, after recent spatial expansion in Poland revealed by sex-linked markers.

    PubMed

    Swisłocka, Magdalena; Czajkowska, Magdalena; Duda, Norbert; Danyłow, Jan; Owadowska-Cornil, Edyta; Ratkiewicz, Mirosław

    2013-01-01

    In recent years, human activity directly and indirectly influenced the demography of moose in Poland. The species was close to extinction, and only a few isolated populations survived after the Second World War; then, unprecedented demographic and spatial expansions had occurred, possibly generating a very complex pattern of population genetic structure at the present-day margins of the species range in Poland. Over 370 moose from seven populations were collected from Poland, and partial sequences of the mitochondrial control region (mtDNA-cr; 607 bp) were obtained. In addition, the entire mtDNA cytochrome b gene (1,140 bp) and Y-chromosome markers (1,982 bp in total) were studied in a chosen set of individuals. Twelve mtDNA haplotypes that all belonged to the European moose phylogroup were recorded. They could be divided into two distinct clades: Central Europe and the Ural Mountains. The first clade consists of three distinct groups/branches: Biebrza, Polesie, and Fennoscandia. The Biebrza group has experienced spatial and demographic expansion in the recent past. Average genetic differentiation among moose populations in Poland at mtDNA-cr was great and significant (ΦST = 0.407, p < 0.001). Using mtDNA-cr data, four separate groups of population were recognized using spatial analysis of molecular variance and principal coordinate analysis, including a relict population in Biebrza National Park, a reintroduced Kampinos National Park population, as well as populations that were descendants of moose that colonized Poland from the east (Lithuania, Belarus, and Ukraine) and the north (former East Prussia). Among all the sequenced Y-chromosome markers, polymorphisms were found in the DBY14 marker in three populations only; four haplotypes were recorded in total. No significant differentiation was detected for this Y-linked marker among moose populations in Poland. Our mtDNA study revealed that a variety of different factors-bottleneck, the presence of relict, autochthonous populations, translocations, limited female dispersal, and the colonization from the east and north-are responsible for the observed complex pattern of population genetic structure after demographic and spatial expansion of moose in Poland.

  18. Polymorphisms and variants in the prion protein sequence of European moose (Alces alces), reindeer (Rangifer tarandus), roe deer (Capreolus capreolus) and fallow deer (Dama dama) in Scandinavia.

    PubMed

    Wik, Lotta; Mikko, Sofia; Klingeborn, Mikael; Stéen, Margareta; Simonsson, Magnus; Linné, Tommy

    2012-07-01

    The prion protein (PrP) sequence of European moose, reindeer, roe deer and fallow deer in Scandinavia has high homology to the PrP sequence of North American cervids. Variants in the European moose PrP sequence were found at amino acid position 109 as K or Q. The 109Q variant is unique in the PrP sequence of vertebrates. During the 1980s a wasting syndrome in Swedish moose, Moose Wasting Syndrome (MWS), was described. SNP analysis demonstrated a difference in the observed genotype proportions of the heterozygous Q/K and homozygous Q/Q variants in the MWS animals compared with the healthy animals. In MWS moose the allele frequencies for 109K and 109Q were 0.73 and 0.27, respectively, and for healthy animals 0.69 and 0.31. Both alleles were seen as heterozygotes and homozygotes. In reindeer, PrP sequence variation was demonstrated at codon 176 as D or N and codon 225 as S or Y. The PrP sequences in roe deer and fallow deer were identical with published GenBank sequences.

  19. Polychlorinated dibenzo-p-dioxins, dibenzofurans, and polychlorinated biphenyls in semi-domesticated reindeer (Rangifer tarandus tarandus) and wild moose (Alces alces) meat in Finland.

    PubMed

    Suutari, Anniina; Ruokojärvi, Päivi; Hallikainen, Anja; Kiviranta, Hannu; Laaksonen, Sauli

    2009-05-01

    Semi-domesticated reindeer and wild moose meat samples were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs). Both calves and adults were studied. Individual reindeer and moose meat samples and pooled reindeer calf meat samples were collected from the northern, the middle, and the southern reindeer herding regions in Finland. Samples represented the edible parts of carcasses. In individual samples of reindeer the fat based WHO-PCDD/F-PCB-TEQ concentration was on average 3.2pgg(-1) in calves and 2.3pgg(-1) in adults. In moose calves the fat based WHO-PCDD/F-PCB-TEQ concentration (1.9pgg(-1)) was lower than in reindeer calves. WHO-PCDD/F-PCB-TEQ concentration in the adult moose samples was equal as in the adult reindeer samples. The mean fat based WHO-PCDD/F-PCB-TEQ concentration was highest in reindeer calf samples from the middle region. These samples contained also the highest content of fat. Individual samples of reindeer contained on average more WHO-PCB-TEQ than WHO-PCDD/F-TEQ, while the opposite was true for moose samples, and also samples of adult reindeer from the southern area. The contributions of PCDD/Fs and PCBs to the total TEQ were similar in the reindeer calves' pooled samples which were collected from more western regions than individual samples.

  20. Relationship between Cd and Zn concentration in the kidneys, liver, and muscles of moose (Alces alces) from north-eastern Poland.

    PubMed

    Skibniewski, Michał; Skibniewska, Ewa M; Kośla, Tadeusz; Olbrych, Katarzyna

    2017-01-01

    The aim of the study was to evaluate the cadmium and zinc content in the kidneys and liver of moose from north-eastern Poland. Animals were divided with respect to their age. The mean concentration of cadmium in the kidneys of moose studied was 11.31 mg kg(-1), while in the liver it amounted to 2.68 mg kg(-1). Age had a significant effect on the content of cadmium in both organs. In the muscles of most animals studied, the cadmium concentrations were below the detection limit. Elevated concentrations were found in three individuals only. Older animals had over six times higher concentrations of cadmium in both kidneys and liver than younger individuals. The cadmium content in kidneys increased with animals' age while no such relationship was found for zinc. Although older animals had higher mean concentrations of zinc in kidneys, liver, and muscles, the two age groups did not differ significantly. The mean concentration of zinc in the kidneys of moose studied was 38.83 mg kg(-1), while in the liver it amounted to 29.03 mg kg(-1). The cadmium concentration in the kidneys was significantly correlated with the cadmium concentration in the liver (r = 0.53, p ≤ 0.01) and with the zinc concentration in the kidneys (r = 0.52, p ≤ 0.01). The data obtained within study correspond with analyses results of the organs of healthy moose in Sweden.

  1. Detection of eastern equine encephalitis virus antibodies in moose (Alces americana), Maine, 2010.

    PubMed

    Lubelczyk, Charles; Elias, Susan P; Kantar, Lee; Albert, Jennifer; Hansen, Stephen; Saxton-Shaw, Kali; MacMillan, Katharine; Smith, Leticia B; Eisen, Rebecca; Swope, Bethany; Smith, Robert Pease; Mutebi, John-Paul

    2014-01-01

    Moose sera were collected from harvested animals during the 2010 hunting season in Maine. Of the 145 serum samples screened by plaque reduction neutralization test (PRNT), 16 (11%) had antibodies to eastern equine encephalitis virus (EEEV). Positive samples were collected from Aroostook County (n=13), Somerset County (n=2), and Piscataquis County (n=1) in northern and central Maine. Preliminary mosquito surveillance revealed the presence of enzootic and bridge vectors mosquitoes, including Culiseta (Climacura) melanura (Coquillett), Aedes (Aedimorphus) vexans (Meigen), and Coquillettidia (Coquillettidia) perturbans (Walker). Select mosquito species were tested by RT-PCR for the presence of EEEV. None were positive. This is the first report of EEEV in moose from Maine.

  2. Processing and Characterization of Porous Ti2AlC with Controlled Porosity and Pore Size

    DTIC Science & Technology

    2012-09-11

    fabricated by spark plasma sintering , were also characterized. The effects of porosity and/or pore size on the room temperature elastic moduli...pressureless- sintered without NaCl pore former, or fabricated by spark plasma sintering , were also characterized. The effects of porosity and/or pore size...as well as several samples sintered using spark plasma sintering (SPS). Furthermore, we demon- strate that the developed methodology can be implemented

  3. Materials Data on Ta4AlC3 (SG:194) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  4. Geophysical prospection of the Roman city of Pollentia, Alcúdia (Mallorca, Balearic Islands, Spain)

    NASA Astrophysics Data System (ADS)

    Ranieri, G.; Godio, A.; Loddo, F.; Stocco, S.; Casas, A.; Capizzi, P.; Messina, P.; Orfila, M.; Cau, M. A.; Chávez, Mª. E.

    2016-11-01

    We present the results of the geophysical investigation carried out in the Roman city of Pollentia, in the island of Mallorca. The ancient city was identified in the 19th century. Old and new archaeological excavations have helped to uncover a residential area, a theatre, the forum, several necropolises and other remains of the city, but a large unexplored area has still to be investigated. For instance, the limits of the ancient town and the presence of harbour structures are still unknown. The geophysical survey has covered an area of more than 20.000 m2 by integrating magnetic, electromagnetic, electrical and ground penetrating radar (GPR) methods. Many unseen archaeological features were clearly revealed by the interpretation of the resistivity maps and GPR time slices. A new method for the visualisation of the geophysical evidence based on VRML (Virtual Reality Markup Language) 3D data representation provides promising results to drive future excavations. The VRML shows a great potentiality for the digital visualization of the site aimed at its exploitation and usability even without the archaeological excavation.

  5. Materials Data on Nb3AlC2 (SG:194) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-04-23

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  6. Materials Data on Nb2AlC (SG:194) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-04-23

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  7. The Effects of Employing HVM on C-130 Aircraft at WR-ALC to Aircraft Availability

    DTIC Science & Technology

    2011-06-01

    information system capability 16 enables the synchronized planning, scheduling, data collection, and analysis required to implement a highly choreographed ...support requirements such as standard work through visual workcards, choreographed tasks, and required material through POU kits to ensure the...is accomplished on the aircraft. If daily work is standardized in terms of work performed and choreographed in sequence; the condition of the

  8. Materials Data on Mn3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  9. Materials Data on Nd3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. EVALUATION OF PROPYLENE CARBONATE IN AIR LOGISTICS CENTER (ALC) DEPAINTING OPERATIONS

    EPA Science Inventory

    This report summarizes a two-phase, laboratory-scale screening study that evaluated solvent blends containing propylene carbonate (PC) as a potential replacement for methyl ethyl ketone (MEK) in aircraft radome depainting operations. The study was conducted at Oklahoma City Air L...

  11. Analysis of the Oklahoma City Air Logistics Center’s (ALC) Contract Management Processes

    DTIC Science & Technology

    2007-12-01

    for Acquisition, Technology, and Logistics, 2007) Table 2. AT&L Workforce by Generation (From Amour , 2002) These main issues are what led...June 14, 2007, from http://www.afmc.af.mil/library/mission.asp Amour , S. (2002, November 6). Generation Y They’ve arrived at work with a new attitude

  12. Materials Data on Dy3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  13. Materials Data on Sc3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-05

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  14. Materials Data on Ho3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-05

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on Nb4AlC3 (SG:194) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2016-04-01

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on Y3AlC (SG:221) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. An analytical platform for cumulative impact assessment based on multiple futures: the impact of petroleum drilling and forest harvesting on moose (Alces alces) and marten (Martes americana) habitats in northeastern British Columbia.

    PubMed

    Strimbu, Bogdan; Innes, John

    2011-07-01

    The combined influence on the environment of all projects occurring in a single area is evaluated through cumulative impact assessments (CIA), which consider the consequences of multiple projects, each insignificant on its own, yet important when evaluated collectively. Traditionally, future human activities are included in CIA using an analytical platform, commonly based on complex models that supply precise predictions but with reduced accuracy. To compensate for the lack of accuracy in current CIA approaches, we propose a shift in the paradigm governing CIA. The paradigm shift involves a change in the focus of CIA investigations from the detailed analysis of one unlikely future to the identification of the patterns describing multiple potential future changes in the environment. To illustrate the approach, a set of 144 possible and equally likely futures were developed that aimed to identify the potential impacts of forest harvesting and petroleum drilling on the habitat suitability of moose and marten in northeast British Columbia, Canada. The evolution of two measures of habitat suitability (average habitat suitability index and surface of the stands with habitat suitability index >0.5) revealed that the human activities could induce cycles in the habitat dynamics of moose and marten. The planning period of 100 years was separated into three distinct periods following a sinusoidal pattern (i.e., increase - constant - decrease in the habitat suitability measures). The attributes that could induce significant changes in the assessment of environment are the choice of harvesting age and species.

  18. Technology Insertion (TI)/Industrial Process Improvement (IP) Task Order Number 14. Contract Summary Report/Quick Fix Plan for SA-ALC/MAEPNC (Cleaning). Volume 5. SA-ALC

    DTIC Science & Technology

    1990-11-16

    DISASSEMBLE ITEM SORT PER PICTURE BOOK If[PLACE IN BASKET OR O PALLET I TAG FOR PROCESS iA AUTOMATED CLEANING j.YES - CLEANUREQUIED NO HAND CLEANING...requiring cleaning are sorted by cleaning process and placed in stainless steel wire baskets or onto plastic pallets . A stainless steel tag is attached to...engine parts can be stored/hung while they await assembly. With this arrangement (rather than the current system of storing these parts in the stacker

  19. Applications of Adaptive Learning Controller to Synthetic Aperture Radar.

    DTIC Science & Technology

    1985-02-01

    FIGURE 37. Location of Two Sub- Phase Histories to be Utilized in Estimating Misfocus Coefficients A and C . . . A8 FIGURES 38.-94. ALC Learning Curves ...FIGURES (Concl uded) FIGURE 23. ALC Learning Curve .... .................. ... 45 .- " FIGURE 24. ALC Learning Curve ......... ................. 47 FIGURE...25. ALC Learning Curve .... .................. ... 48 FIGURE 26. ALC Learning Curve ....... .... ... .... 50 FIGURE 27. ALC Learning Curve

  20. A new dinosaur (Theropoda, Spinosauridae) from the Cretaceous (Cenomanian) Alcântara Formation, Cajual Island, Brazil.

    PubMed

    Kellner, Alexander W A; Azevedo, Sergio A K; Machado, Elaine B; Carvalho, Luciana B de; Henriques, Deise D R

    2011-03-01

    A new spinosaurid taxon, Oxalaia quilombensis gen. et sp. nov., is described based on the anterior part of a snout and a fragment of a maxilla. These specimens were collected at the Laje do Coringa site, Late Cretaceous (Cenomanian) of the São Luis Basin. Unlike Cristatusaurus and Suchomimus, Oxalaia quilombensis lacks serrations on the teeth. The new species differs from Angaturama limai by having the anterior part of the premaxillae more expanded and by lacking a sagittal premaxillary crest. It further differs from Spinosaurus cf. S. aegyptiacus and the Algerian spinosaurid by the rounder shape of the terminal expansion. Furthermore, xalaia quilobensis has one functional tooth followed by two replacement teeth, a feature not previously observed in theropods. Oxalaia quilombensis appears to be more closely related to the spinosaurids found in North Africa than to the Brazilian members of this clade and thus further increases the diversity of these enigmatic predatory dinosaurs in this country.

  1. 40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu...

  2. 40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu...

  3. 40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu...

  4. 40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu...

  5. 40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu...

  6. Technology Insertion Engineering Services Process Characterization Task Order No. 1. (Block II). Database Documentation Book for OC-ALC MATPCA

    DTIC Science & Technology

    1989-09-11

    as possible, the Taguchi method of using fractional factorials in the form of orthogonal arrays is considered a method of choice. Two terms require...8217,-=- ,--, 11 I II .44 .44"I . 0 c p ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (. TABLE40 EXPERIMENTAL FLOW TIME AVERAGES - EXP

  7. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1 Volume 3. OC-ALC Book 2 of 2

    DTIC Science & Technology

    1989-12-15

    Douglas Missile Systems Company 6.14-14 TASK ORDER NO. 1 PROCESS CHARACTERIZATION *i ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L4...Systems Company 6.15-12 TASK ORDER NO. 1 PROCESS CHARACTERIZATION 0ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L4) TABLE 6.15.2-2...1 PROCESS CHARACTERIZATION ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L4) TABLE 6.16.2-2 EXPERIMENTAL FLOW TIME AVERAGES EXP

  8. Arthroscopic Latarjet and Capsular Shift (ALCS) procedure: a new "freehand" technique for anterior shoulder instability associated with significant bone defects.

    PubMed

    Bhatia, Deepak N

    2015-03-01

    Anterior shoulder instability associated with significant bone loss has been described as "bony-instability," and this condition is usually treated with an anterior glenoid bone grafting procedure (Latarjet procedure). The Latarjet procedure involves transfer of the horizontal limb of the coracoid process along with the conjoint tendon to the anterior glenoid rim, and is traditionally performed as an open surgical procedure. Recently, an arthroscopic technique for the Latarjet procedure has been described; the technique necessitates the use of specialized instrumentation and involves excision of the entire anterior capsule to facilitate coracoid fixation. We describe a new "freehand" arthroscopic technique for the Latarjet procedure, and, in addition, a simultaneous capsular shift to further optimize mid and end range stability. This technique eliminates the use of additional instrumentation and can be done using routine arthroscopic instruments. Preliminary experience with this technique suggests that the arthroscopic Latarjet and capsular shift is a technically demanding procedure. Glenohumeral capsule can be preserved, and this should be attempted wherever possible to optimize stability. Additional specialized instrumentation would probably reduce surgical time; however, the procedure can be performed with routine instruments.

  9. CRADA (AL-C-2009-02) Final Report: Phase I. Lanthanum-based Start Materials for Hydride Batteries

    SciTech Connect

    Gschneidner, Jr., Karl; Schmidt, Frederick; Frerichs, A. E.; Ament, Katherine A.

    2013-05-01

    The purpose of Phase I of this work is to focus on developing a La-based start material for making nickel-metal (lanthanum)-hydride batteries based on our carbothermic-silicon process. The goal is to develop a protocol for the manufacture of (La{sub 1-x}R{sub x})(Ni{sub 1-y}M{sub y})(Si{sub z}), where R is a rare earth metal and M is a non-rare earth metal, to be utilized as the negative electrode in nickel-metal hydride (NiMH) rechargeable batteries.

  10. The effect of composition and cooling rate on the structure of rapidly solidified (Fe, Ni)3Al-C alloy

    NASA Technical Reports Server (NTRS)

    Myers, S. A.; Koch, C. C.

    1989-01-01

    The quench rate-metastable structure dependence in the Fe-20Ni-8Al-2C wt pct alloy has been experimentally studied. The nonequilibrium gamma-prime and gamma phases were noted in foils 65-100 microns thick, while at higher quench rates (thinner samples) the matrix was found to be in a disordered fcc gamma phase with kappa carbide precipitates. With the addition of silicon to the alloys, the nonequilibrium gamma-prime and gamma structures are observed at higher cooling rates.

  11. Transcriptional Analysis of the Bordetella Alcaligin Siderophore Biosynthesis Operon

    PubMed Central

    Kang, Ho Young; Armstrong, Sandra K.

    1998-01-01

    The alc gene cluster of Bordetella pertussis includes three genes, alcA, alcB, and alcC, which are involved in alcaligin siderophore biosynthesis in response to iron starvation. The production of AlcA, AlcB, and AlcC in Bordetella cells and the transcriptional organization of alcA, alcB, and alcC were investigated by using a set of three alc′-′lacZ gene fusion constructs that were contiguous with the known promoter upstream of alcA and extended to fusion junctions within each alc cistron. All three alc′-′lacZ fusions exhibited iron-repressible reporter gene expression which was abolished by deletion of the 105-bp alcA promoter-operator region. In an immunoblot analysis using a monoclonal antibody specific for β-galactosidase, the AlcA-LacZ, AlcB-LacZ, and AlcC-LacZ hybrid proteins were detected in Bordetella cells grown under iron-depleted conditions. A B. pertussis mutant in which the 105-bp alcA promoter-operator region was deleted by allelic exchange was unable to produce detectable levels of siderophore. Hybridization analysis using gene-specific probes showed that alc-specific transcript levels in the mutant were negligible compared with those of the wild-type parent. These results confirm that alcA, alcB, and alcC are cotranscribed from an iron-regulated control region immediately upstream of alcA. Transcript analysis using hybridization probes representing regions downstream of alcC demonstrated that alc transcription extends approximately 3.6 kb further downstream from the alcC coding region, suggesting the cotranscription of additional, uncharacterized alcaligin system genes. PMID:9473039

  12. Systems Harmonization and Convergence - the GIGAS Approach

    NASA Astrophysics Data System (ADS)

    Marchetti, P. G.; Biancalana, A.; Coene, Y.; Uslander, T.

    2009-04-01

    0.1 Background The GIGAS1 Support Action promotes the coherent and interoperable development of the GMES, INSPIRE and GEOSS initiatives through their concerted adoption of standards, protocols, and open architectures. 0.2 Preparing for Coordinated Data Access The GMES Coordinated Data Access System is under design and implementation2. This objective has motivated the definition of the interoperability standards between the contributing missions. The following elements have been addressed with associated papers submitted to OGC: The EO Product Metadata has been based on the OGC Geographic Markup Language, addressing sensor characteristics for optical, radar and atmospheric products. Collection and service discovery: an ISO extension package for CSW ebRim has been proposed. Catalogue Service (CSW): an Earth Observation extension package of the CSW ebRim has been proposed. Feasibility Analysis and Order: an Order interface control document and an Earth Observation profile of the Sensor Planning Service have been proposed. Online Data Access: an Earth Observation profile of the Web Map Services (WMS) for visualization and evaluation purposes has been proposed. Identity (user) management: the objective in the long term is to allow for a single sign-on to the Coordinated Data Access system by users registered in the various Earth Observation ground segments by providing a federated identity across participating ground segments, exploiting OASIS standards. 0.3 The GIGAS proposed harmonization approach The approach proposed by GIGAS is based on three elements: Technology watch Comparative analysis Shaping of initiatives and standards This paper concentrates on the methodology for technology watch and comparative analysis. The complexity of the GIGAS scenario involving huge systems (i.e. GEOSS, INSPIRE, GMES etc.) entails the interaction with different heterogeneous partners, each with a specific competence, expertise and know-how. 0.3.1 Technology watch The methodology

  13. GigaDB: promoting data dissemination and reproducibility

    PubMed Central

    Sneddon, Tam P.; Si Zhe, Xiao; Edmunds, Scott C.; Li, Peter; Goodman, Laurie; Hunter, Christopher I.

    2014-01-01

    Often papers are published where the underlying data supporting the research are not made available because of the limitations of making such large data sets publicly and permanently accessible. Even if the raw data are deposited in public archives, the essential analysis intermediaries, scripts or software are frequently not made available, meaning the science is not reproducible. The GigaScience journal is attempting to address this issue with the associated data storage and dissemination portal, the GigaScience database (GigaDB). Here we present the current version of GigaDB and reveal plans for the next generation of improvements. However, most importantly, we are soliciting responses from you, the users, to ensure that future developments are focused on the data storage and dissemination issues that still need resolving. Database URL: http://www.gigadb.org PMID:24622612

  14. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 1. Database Documentation Book. OO-ALC MANPRC (Overview Layouts)

    DTIC Science & Technology

    1989-12-15

    steels will electropolish and 1. Carbon steels trouble degreasing. High-nickel al- plate smoother at longer reverse cy- 2. Nickel e loys, 16% or higher...PV-RI 1.00 REM RPL PAPRWRK SIGN OFF DOC 101001 .012 0090 UP 01 24 .05 SHOTPEEN SM STEEL PART/MSK .278 .003 ,017 2 0010 E ZMA-CP-S2 1,00 MS SMALL...E RJP-PU-R1 1,00 REM RP. PPIWM SIGN OFF DOC .01001 ,012 0090 UP 01 24 ,05 SHOTPEEN SM STEEL PART/MASK .278 .003 .017 2 0010 E ZMA-CP-2 1,00 MASK SW.L

  15. Technology Insertion (TI)/Industrial Process Improvement (IPI) Task Order Number 15, Data Base Documentation Book SA-ALC/MAE & MAT

    DTIC Science & Technology

    1990-12-14

    HSG. 2675.73 2174 207 198 61.8 2623.65 2016 197 198 59.8 𔃻lIW IZZLE 180 1524.31 -1183 106 108 19.1 1794.91 1412 -110 108 22 𔃻I iE NOZZLE 397...1162.1 147.0 144.0 36.7 AO=ZMY CASE 457.2 199.4 262.5 264.0 13.8 B , HCP 180 1270.5 415.6 146.0 144.0 21.1 BACStIP 397 771.7 726.4 265.5 264.0 23.5

  16. Technology Insertion (TI)/Industrial Process Improvement (IPI). Task Order no. 1 (Misc Manufacturing). Book 1. Database Documentation Book for OO-ALC MANPWW (Overview Layouts)

    DTIC Science & Technology

    1989-12-15

    materials to be sprayed. These basic forms are gas combustion and electric arc. The gas combustion process uses oxygen and acetylene as a heating source...OS Acetylene . Technical. Dissolved In-N-800 iydreen 23-0-192 Oxygo. Technical. Gas and Liquid STANDARDI MIL ITART MIL-STD-808 Grinding of Chrome...about layout3 equipment and processes r or this ROC. *Misc Manufacturing - Flame spr’ay, casting, heat treat, welding 14. SUBJECT TERMS ~ )T

  17. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 1 of 2. Database Documentation Book. OO-ALC MANPRB (Overview Layouts)

    DTIC Science & Technology

    1989-12-15

    MNS 4-1’/S#9ED N//f PRESEL/T Jr475 A/ID R46 IArA AE A-ED / r AO Z~’f/RS TI/ATr /;T /Y IP TO0 XPeC/F/C/7,eT 6O’! TIf/I rACEr r,6 4 , ?r ’Vr T0 PA’i k/AZZ...16.02 0.0009 0.S709 117 26578A 1620ND0S3797G ORG BRAC 14.56 0.0008 0.9797 118 15521A 1630008562073 FBIul PP 14.35 0.0008 0.9805 119 69887A 1620007057261

  18. Molecular dynamic study of the mechanism of formation of 2D carbon nanostructures in a solid Al-C nanocomposite grain

    NASA Astrophysics Data System (ADS)

    Galashev, A. E.; Elshina, L. A.; Muradymov, R. V.

    2016-12-01

    The behavior of graphene fragments in the structural fcc grains of aluminum was studied by molecular dynamics. In the course of structural relaxation, the graphene sheets united, twisted, and shifted toward the grain boundaries. The structure of the formed nanocomposite grain was studied in detail by statistical geometry. The distributions of Voronoi polyhedra according to the number of faces and of faces according to the number of sides were determined, including those after elimination of small-scale thermal fluctuations from the model. The angular distributions of the nearest geometrical neighbors were calculated, and the selfdiffusion coefficients were determined.

  19. Technology Insertion (TI)/Industrial Process Improvement (IP) Task Order Number 18. Contract Summary Report/Quick Fix Plan for OO-ALC (Optical Repair).

    DTIC Science & Technology

    1991-01-30

    ITEM SERIAL NO 10 MOOEL.CESIGN- SERIES ~I I STOCK( NUMBER [ 12 OPTIONAL 13 SERIAL NUMBER IA NOUN DISPAITCH PERK RCC’OP I1 STAT CN NO WCRK yO BE AC:OMPLISHE...15 DATE SCHED 6 DATt COMPLETED 7 PART NUMBER A TECH DATA 9 ITEM SERIAL NO 10 MODEL DESIGN SERIES I I STOCK NUMBER 12 OPTIONAL 13 SFRIAL NUMBER 14 NOUN...PMNUBE UTEHDATA 9 ITEM SERIAL NO f* SO MOOIEL.DIESIGN- SERIES I I STOCK NUMBER 12 OPTIONAL 13 SERIAL NUMBER Ii NOUN 55 16 1? is 19 20 DISPATCH PERF

  20. Substantiation of Epitaxial Growth of Diamond Crystals on the Surface of Carbide Fe3AlC0.66 Phase Nanoparticles

    NASA Astrophysics Data System (ADS)

    Dzevin, Ievgenij M.; Mekhed, Alexander A.

    2017-03-01

    Samples of Fe-Al-C alloys of varying composition were synthesized under high pressures and temperatures. From X-ray analysis data, only K-phase with usual for it average parameter of elemental lattice cell, a = 0.376 nm, carbide Fe3C and cubic diamond reflexes were present before and after cooling to the temperature of liquid nitrogen.

  1. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. (Block 2). Database Documentation Book. Book 1 of 2. OC-ALC MATPCB

    DTIC Science & Technology

    1989-09-11

    0.375 0. 160 inch inch m3 4 6 L-119382-0 1. 0.542 - 0.552 inch diameter through 0. 150 - 0.157 inch for hardface buildup hole 5. 0.016 - 0.047 inch radius...2. 0.177 - 0.181 inch 6. 1.945 - 1.955 inches 3. 0. 550 - 0.570 inch 7. Weld build up ( hardface overlay) 4. 0.060 - 0.070 inch for parent metal

  2. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 2 of 3. Database Documentation Book. OO-ALC MANPGW (Brakes - WCD’S)

    DTIC Science & Technology

    1989-12-15

    m........e...m.... M Pe N In - NM 99 t N ~ im c 4N wm9 mo vc vwv Name P - Nt 9-4np @-MmNmne - m i ov4cen c 90cn0 0 9cm.me,-eC- meM N4 --9 men C P ...0--N0-4O ow &=W& 400000 0000 0000c00 00000 0 0000000000000000 S0000000 00 0000000c00000 0 00000000000000000c ILMO m9-N-4ccM p a t 09-4- 0Mmnn dom99 MM...4NM4N W4CN MC9 -4 n N-4 44 N 4 O1ane4N0 ; 40 nw i 40 hn- " moNP. *9- v AnWCn -0 qmm 4 kn 40 " m t-- 4 n : -w4 rn - Inq n NO6P.". P N-04"C~tr oq C 4 N

  3. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 3 of 3. Database Documentation Book. OO-ALC MANPGW (Brakes - Profiles)

    DTIC Science & Technology

    1989-12-15

    l 17%’ if- I- 0 L1L1 -I I I -1--- 00 U)) co 4Z0 J I cc I I IK IL I I IL I - - - I 0 I I I I- I I -I alI I l ol : IZ ICA a .~ I MEI I 0~ .~ I I 0-I ImeI...DRILL AND TAP OLE . 5250W .1525 0020 E RJP-PW-R1 1.00 REM RPI. PAPRWRK SIGN OFF DOC .01001 .010 9000 JA 01 00 .00 LABOR STANDRD HISTORY .000 .000 .000...CLEANED A-ND PROTECTE:’i (C/P MOVE) FOR __________ MOVES BETWIEEN O.-PERA-T :OEN/D:. ESPA *T(H _____ _____ ______ STA1T IONS. :~ 4::: 4 :::: . . *W A

  4. Technology Insertion-Engineering Services Process Characterization Task Order No. 1. Book 2 of 3. Database Documentation Book. OO-ALC MANPGP (Wheels - WCD’S)

    DTIC Science & Technology

    1989-12-15

    bEAFIN! BCRE & LOCK RING GROOVE M 8FPAIF IN-OARr) IAW lIG EB & PAGE 1£ PARA X-1 _’C/P MCVE _ _.- Z40 70 TREAT (DOW 7, *C/P MOVE 13 i&0 IrPREGNA IE tC...SPECIIIED- IN ’THIS rOCUM--fT ___ HAE UKWN THOROUGHLY TRAINEE AND A Ei FAMILIA . WIT’- ALL PER’ININT SAFETY PRACTICES ArL- HAZARDS GCNTAINED IN THE BASIC...04265 053 0090 E RWB-D-HT- 1.00 REM EAT SHIELD (SINGLE PC) .00217 .002 0100 E RJP-DW-TI 1.00 REM LIL PAPRWRK SIGN BOFF DOC .01001 .012 0006 EB 0 -1 25

  5. Technology Insertion-Engineering Services Process Characterization. Technology Insertion (TI)/Industrial Process Improvement (IPI) Task Order Number 1. OC-ALC/MATPCC, Electromechanical Unit

    DTIC Science & Technology

    1989-09-11

    I- ! • :.. I, I I I I .I I- -- o I -I I ... I " I Il :.: -II I I ," " , I I I ’ I "I Ii 𔃻 _ I I I~ I , -. ,- I , ,- - I . - -I - . ... I ... I...II.I QI , I. , II H, .0 - - I -.l -I - - I - I I: LL1 " L I !Ii II... l I I I I- I °i 0 Ii I I I ! llii il J I g ul Il l l l m kli j ii ll LI...I2 1~ lIl tfl i l[ft11 1111.Iil is 11 w 4I -1T1TT7 TE r r lI-Illlit ii II il z t m iI I 11 lii ill II C4C ui i -weN I ~ -x TTT TT TTOT -m l l QIII

  6. Population structure of the giant garter snake, Thamnophis gigas

    USGS Publications Warehouse

    Paquin, M.M.; Wylie, G.D.; Routman, E.J.

    2006-01-01

    The giant garter snake, Thamnophis gigas, is a threatened species endemic to California's Central Valley. We tested the hypothesis that current watershed boundaries have caused genetic differentiation among populations of T. gigas. We sampled 14 populations throughout the current geographic range of T. gigas and amplified 859 bp from the mitochondrial gene ND4 and one nuclear microsatellite locus. DNA sequence variation from the mitochondrial gene indicates there is some genetic structuring of the populations, with high F ST values and unique haplotypes occurring at high frequency in several populations. We found that clustering populations by watershed boundary results in significant between-region genetic variance for mtDNA. However, analysis of allele frequencies at the microsatellite locus NSU3 reveals very low F ST values and little between-region variation in allele frequencies. The discordance found between mitochondrial and microsatellite data may be explained by aspects of molecular evolution and/or T. gigas life history characteristics. Differences in effective population size between mitochondrial and nuclear DNA, or male-biased gene flow, result in a lower migration rate of mitochondrial haplotypes relative to nuclear alleles. However, we cannot exclude homoplasy as one explanation for homogeneity found for the single microsatellite locus. The mitochondrial nucleotide sequence data supports conservation practices that identify separate management units for T. gigas. ?? Springer 2006.

  7. Towards decoding the conifer giga-genome.

    PubMed

    Mackay, John; Dean, Jeffrey F D; Plomion, Christophe; Peterson, Daniel G; Cánovas, Francisco M; Pavy, Nathalie; Ingvarsson, Pär K; Savolainen, Outi; Guevara, M Ángeles; Fluch, Silvia; Vinceti, Barbara; Abarca, Dolores; Díaz-Sala, Carmen; Cervera, María-Teresa

    2012-12-01

    Several new initiatives have been launched recently to sequence conifer genomes including pines, spruces and Douglas-fir. Owing to the very large genome sizes ranging from 18 to 35 gigabases, sequencing even a single conifer genome had been considered unattainable until the recent throughput increases and cost reductions afforded by next generation sequencers. The purpose of this review is to describe the context for these new initiatives. A knowledge foundation has been acquired in several conifers of commercial and ecological interest through large-scale cDNA analyses, construction of genetic maps and gene mapping studies aiming to link phenotype and genotype. Exploratory sequencing in pines and spruces have pointed out some of the unique properties of these giga-genomes and suggested strategies that may be needed to extract value from their sequencing. The hope is that recent and pending developments in sequencing technology will contribute to rapidly filling the knowledge vacuum surrounding their structure, contents and evolution. Researchers are also making plans to use comparative analyses that will help to turn the data into a valuable resource for enhancing and protecting the world's conifer forests.

  8. The NA62 GigaTracker

    NASA Astrophysics Data System (ADS)

    Aglieri Rinella, G.; Feito, D. Alvarez; Arcidiacono, R.; Biino, C.; Bonacini, S.; Ceccucci, A.; Chiozzi, S.; Gil, E. Cortina; Ramusino, A. Cotta; Degrange, J.; Fiorini, M.; Gamberini, E.; Gianoli, A.; Kaplon, J.; Kluge, A.; Mapelli, A.; Marchetto, F.; Minucci, E.; Morel, M.; Noël, J.; Noy, M.; Perktold, L.; Perrin-Terrin, M.; Petagna, P.; Petrucci, F.; Poltorak, K.; Romagnoli, G.; Ruggiero, G.; Velghe, B.; Wahl, H.

    2017-02-01

    The GigaTracker is a hybrid silicon pixel detector built for the NA62 experiment aiming at measuring the branching fraction of the ultra-rare kaon decay K+ →π+ ν ν bar at the CERN SPS. The detector has to track particles in a beam with a flux reaching 1.3 MHz/mm2 and provide single-hit timing with 200 ps RMS resolution for a total material budget of less than 0.5% X0 per station. The tracker comprises three 60.8 mm×27 mm stations installed in vacuum (∼10-6 mbar) and cooled with liquid C6F14 circulating through micro-channels etched inside a few hundred micron thick silicon plates. Each station is composed of a 200 μm thick silicon sensor read out by 2×5 custom 100 μm thick ASICs, called TDCPix. Each chip contains 40×45 asynchronous pixels, 300 μm×300 μm each and is instrumented with 100 ps bin time-to-digital converters. In order to cope with the high rate, the TDCPix is equipped with four 3.2 Gb/s serialisers sending out the data. We will describe the detector and the results from the 2014 and 2015 NA62 runs.

  9. The ratio of absolute lymphocyte count at interim of therapy to absolute lymphocyte count at diagnosis predicts survival in childhood B-lineage acute lymphoblastic leukemia.

    PubMed

    Cheng, Yuping; Luo, Zebin; Yang, Shilong; Jia, Ming; Zhao, Haizhao; Xu, Weiqun; Tang, Yongmin

    2015-02-01

    Absolute lymphocyte count (ALC) after therapy has been reported to be an independent prognostic factor for clinical outcome in leukemia. This study mainly analyzed ALC at interim of therapy on day 22 (ALC-22) and the ratio of ALC-22 to ALC at diagnosis (ALC-0) on the impact of survival and the relation of ALC to lymphocyte subsets in 119 pediatric B-lineage acute lymphoblastic leukemia (B-ALL) patients. Univariate analysis revealed that ALC-22/ALC-0 ratio <10% was significantly associated with inferior overall survival (OS) (hazard ratio (HR)=12.24, P=0.0014) and event-free survival (EFS) (HR=3.3, P=0.0046). In multivariate analysis, ALC-22/ALC-0 ratio remained an independent prognostic factor for OS (HR=6.92, P=0.0181) and EFS (HR=2.78, P=0.0329) after adjusting for age, white blood cell (WBC) count and minimal residual disease (MRD) status. A Spearman correlation test showed that CD3+ T cells had a negative correlation with ALC-0 (r=-0.7204, P<0.0001) and a positive correlation with ALC-22 (r=0.5061, P=0.0071). These data suggest that ALC-22/ALC-0 ratio may serve as a more effective biomarker to predict survival in pediatric B-ALL and ALC is mainly associated with CD3+ T cells.

  10. Heritability of shell pigmentation in the Pacific oyster, Crassostrea gigas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pacific oyster (Crassostrea gigas) is a species of considerable economic importance, with among the highest global production of any cultured aquatic animal species. In the interest of increasing the value of Pacific oysters sold as “singles” for the half-shell market, we explored the feasibili...

  11. Analysis of Government Accountability Office Bid Protests in Air Force Source Selections over the Past Two Decades

    DTIC Science & Technology

    2012-01-01

    ALCs) include Oklahoma City ALC, Tinker AFB ; Ogden ALC, Hill AFB ; Warner Robins ALC, Robins AFB ; and, before 2001, Sacramento ALC, McClellan AFB ...she had worked with in the past. Megan McKeever was always ready to provide helpful administrative support. xvii Abbreviations AFB Air Force base...are Langley Air Force Base ( AFB ), Air Combat Command; Peterson AFB , Air Force Space Command; Scott AFB , Air Mobility Command; Ramstein Air Base

  12. Continuous Process Improvement at Tinker Air Logistics Complex

    DTIC Science & Technology

    2013-03-01

    Abstract The Air Logistics Complexes (ALC) represent the Air Force’s largest Maintenance, Repair, and Overhaul ( MRO ) Operations. The ALCs strive to...this problem is important to the ALCs because it provides a roadmap for how to sustain Maintenance, Repair and Overhaul ( MRO ) actions with less...ALC) represent the Air Force’s largest Maintenance, Repair, and Overhaul ( MRO ) Operations. The ALCs strive to become leaner by reducing Work In

  13. Stochasticity of convection in Giga-LES data

    NASA Astrophysics Data System (ADS)

    De La Chevrotière, Michèle; Khouider, Boualem; Majda, Andrew J.

    2016-09-01

    The poor representation of tropical convection in general circulation models (GCMs) is believed to be responsible for much of the uncertainty in the predictions of weather and climate in the tropics. The stochastic multicloud model (SMCM) was recently developed by Khouider et al. (Commun Math Sci 8(1):187-216, 2010) to represent the missing variability in GCMs due to unresolved features of organized tropical convection. The SMCM is based on three cloud types (congestus, deep and stratiform), and transitions between these cloud types are formalized in terms of probability rules that are functions of the large-scale environment convective state and a set of seven arbitrary cloud timescale parameters. Here, a statistical inference method based on the Bayesian paradigm is applied to estimate these key cloud timescales from the Giga-LES dataset, a 24-h large-eddy simulation (LES) of deep tropical convection (Khairoutdinov et al. in J Adv Model Earth Syst 1(12), 2009) over a domain comparable to a GCM gridbox. A sequential learning strategy is used where the Giga-LES domain is partitioned into a few subdomains, and atmospheric time series obtained on each subdomain are used to train the Bayesian procedure incrementally. Convergence of the marginal posterior densities for all seven parameters is demonstrated for two different grid partitions, and sensitivity tests to other model parameters are also presented. A single column model simulation using the SMCM parameterization with the Giga-LES inferred parameters reproduces many important statistical features of the Giga-LES run, without any further tuning. In particular it exhibits intermittent dynamical behavior in both the stochastic cloud fractions and the large scale dynamics, with periods of dry phases followed by a coherent sequence of congestus, deep, and stratiform convection, varying on timescales of a few hours consistent with the Giga-LES time series. The chaotic variations of the cloud area fractions were

  14. Impact of atrazine on aneuploidy in pacific oysters, Crassostrea gigas.

    PubMed

    Bouilly, Karine; Leitão, Alexandra; McCombie, Helen; Lapègue, Sylvie

    2003-01-01

    Aneuploidy has previously been described and studied in the Pacific oyster, Crassostrea gigas, and has been shown to be negatively correlated with growth. The present study investigated the effect of atrazine on the level of aneuploidy in this species. Crassostrea gigas adults and juveniles were subjected to different concentrations of atrazine representing a peak value found in a polluted environment (46.5 nM) and a value 10 times higher (465 nM). Although atrazine did not show any effect on the oyster mortality, significant differences in aneuploidy level were observed between the different treatments (9% for the control, 16% for 46.5 nM and 20% for 465 nM atrazine). Moreover, the same levels of aneuploidy were observed at adult and juvenile stages. This is the first reported evidence for an environmental effect on aneuploidy in C. gigas. These results will be useful for the oyster aquaculture industry and management of resources. The lowest atrazine level in the current study represents realistic potential exposure, and the results suggest that studies should be made on other aquatic species at risk of exposure to atrazine in the wild. This widely used compound may be an important factor causing damage to genetic material.

  15. Identification of the Molecular Clockwork of the Oyster Crassostrea gigas

    PubMed Central

    Perrigault, Mickael; Tran, Damien

    2017-01-01

    Molecular clock system constitutes the origin of biological rhythms that allow organisms to anticipate cyclic environmental changes and adapt their behavior and physiology. Components of the molecular clock are largely conserved across a broad range of species but appreciable diversity in clock structure and function is also present especially in invertebrates. The present work aimed at identify and characterize molecular clockwork components in relationship with the monitoring of valve activity behavior in the oyster Crassostrea gigas. Results provided the characterization of most of canonical clock gene including clock, bmal/cycle, period, timeless, vertebrate-type cry, rev-erb, ror as well as other members of the cryptochrome/photolyase family (plant-like cry, 6–4 photolyase). Analyses of transcriptional variations of clock candidates in oysters exposed to light / dark regime and to constant darkness led to the generation of a putative and original clockwork model in C. gigas, intermediate of described systems in vertebrates and insects. This study is the first characterization of a mollusk clockwork. It constitutes essential bases to understand interactions of the different components of the molecular clock in C. gigas as well as the global mechanisms associated to the generation and the synchronization of biological rhythms in oysters. PMID:28072861

  16. Moderate establishment success of Pacific oyster, Crassostrea gigas, on a sheltered intertidal mussel bed

    NASA Astrophysics Data System (ADS)

    Holm, Mark Wejlemann; Davids, Jens Kristian; Dolmer, Per; Vismann, Bent; Hansen, Benni Winding

    2015-10-01

    The Pacific oyster (Crassostrea gigas Thunberg 1793) is introduced into marine ecosystems worldwide. In Denmark, C. gigas was introduced into the micro tidal Limfjord, around 1972 for aquaculture. This study describes the population structure of C. gigas at Agger Tange in 2007, 2009, 2010 and 2011. Here, C. gigas use beds of Blue mussels (Mytilus edulis L.) as primary habitat. The mean abundance (± 1 SD) of C. gigas was unchanged during our study (45 ± 2 indv. m- 2), while it increased for M. edulis from 2010 to 2011 (934 ± 610 to 1434 ± 750 indv. m- 2, respectively). In 2009, a newly settled cohort of C. gigas was present, but in the succeeding years no or negligible recruitment was recorded. However, age cohort analyses, based on individual shell size at different ages, suggest successful recruitment in three out of seven years. A comparison with the course of the bioinvasion in List Tidal Basin, suggests that the population at Agger Tange is not in the expansion phase of the bioinvasion, despite of frequent settlement, high shell growth rates and relatively high abundance. So far, C. gigas has had moderate establishment success. We conclude that C. gigas is still in the establishment phase, but that this is prolonged, presumably due to low food availability.

  17. A Glycoprotein in Shells of Conspecifics Induces Larval Settlement of the Pacific Oyster Crassostrea gigas

    PubMed Central

    Vasquez, Hebert Ely; Hashimoto, Kyotaro; Yoshida, Asami; Hara, Kenji; Imai, Chisato Chris; Kitamura, Hitoshi; Satuito, Cyril Glenn

    2013-01-01

    Settlement of larvae of Crassostrea gigas on shell chips (SC) prepared from shells of 11 different species of mollusks was investigated. Furthermore, the settlement inducing compound in the shell of C. gigas was extracted and subjected to various treatments to characterize the chemical cue. C. gigas larvae settled on SC of all species tested except on Patinopecten yessoensis and Atrina pinnata. In SC of species that induced C. gigas larvae to settle, settlement was proportionate to the amount of SC supplied to the larvae. When compared to C. gigas SC, all species except Crassostrea nippona showed lower settlement inducing activities, suggesting that the cue may be more abundant or in a more available form to the larvae in shells of conspecific and C. nippona than in other species. The settlement inducing activity of C. gigas SC remained intact after antibiotic treatment. Extraction of C. gigas SC with diethyl ether (Et2O-ex), ethanol (EtOH-ex), and water (Aq-ex) did not induce larval settlement of C. gigas larvae. However, extraction of C. gigas SC with 2N of hydrochloric acid (HCl-ex) induced larval settlement that was at the same level as the SC. The settlement inducing compound in the HCl-ex was stable at 100°C but was destroyed or degraded after pepsin, trypsin, PNGase F and trifluoromethanesulfonic acid treatments. This chemical cue eluted between the molecular mass range of 45 and 150 kDa after gel filtration and revealed a major band at 55 kDa on the SDS-PAGE gel after staining with Stains-all. Thus, a 55 kDa glycoprotein component in the organic matrix of C. gigas shells is hypothesized to be the chemical basis of larval settlement on conspecifics. PMID:24349261

  18. A glycoprotein in shells of conspecifics induces larval settlement of the Pacific oyster Crassostrea gigas.

    PubMed

    Vasquez, Hebert Ely; Hashimoto, Kyotaro; Yoshida, Asami; Hara, Kenji; Imai, Chisato Chris; Kitamura, Hitoshi; Satuito, Cyril Glenn

    2013-01-01

    Settlement of larvae of Crassostrea gigas on shell chips (SC) prepared from shells of 11 different species of mollusks was investigated. Furthermore, the settlement inducing compound in the shell of C. gigas was extracted and subjected to various treatments to characterize the chemical cue. C. gigas larvae settled on SC of all species tested except on Patinopecten yessoensis and Atrina pinnata. In SC of species that induced C. gigas larvae to settle, settlement was proportionate to the amount of SC supplied to the larvae. When compared to C. gigas SC, all species except Crassostrea nippona showed lower settlement inducing activities, suggesting that the cue may be more abundant or in a more available form to the larvae in shells of conspecific and C. nippona than in other species. The settlement inducing activity of C. gigas SC remained intact after antibiotic treatment. Extraction of C. gigas SC with diethyl ether (Et2O-ex), ethanol (EtOH-ex), and water (Aq-ex) did not induce larval settlement of C. gigas larvae. However, extraction of C. gigas SC with 2N of hydrochloric acid (HCl-ex) induced larval settlement that was at the same level as the SC. The settlement inducing compound in the HCl-ex was stable at 100°C but was destroyed or degraded after pepsin, trypsin, PNGase F and trifluoromethanesulfonic acid treatments. This chemical cue eluted between the molecular mass range of 45 and 150 kDa after gel filtration and revealed a major band at 55 kDa on the SDS-PAGE gel after staining with Stains-all. Thus, a 55 kDa glycoprotein component in the organic matrix of C. gigas shells is hypothesized to be the chemical basis of larval settlement on conspecifics.

  19. Population structure and genetic diversity of moose in Alaska.

    PubMed

    Schmidt, Jennifer I; Hundertmark, Kris J; Bowyer, R Terry; McCracken, Kevin G

    2009-01-01

    Moose (Alces alces) are highly mobile mammals that occur across arboreal regions of North America, Europe, and Asia. Alaskan moose (Alces alces gigas) range across much of Alaska and are primary herbivore consumers, exerting a prominent influence on ecosystem structure and functioning. Increased knowledge gained from population genetics provides insights into their population dynamics, history, and dispersal of these unique large herbivores and can aid in conservation efforts. We examined the genetic diversity and population structure of moose (n = 141) with 8 polymorphic microsatellites from 6 regions spanning much of Alaska. Expected heterozygosity was moderate (H(E) = 0.483-0.612), and private alleles ranged from 0 to 6. Both F(ST) and R(ST) indicated significant population structure (P < 0.001) with F(ST) < 0.109 and R(ST) < 0.125. Results of analyses from STRUCTURE indicated 2 prominent population groups, a mix of moose from the Yakutat and Tetlin regions versus all other moose, with slight substructure observed among the second population. Estimates of dispersal differed between analytical approaches, indicating a high level of historical or current gene flow. Mantel tests indicated that isolation-by-distance partially explained observed structure among moose populations (R(2) = 0.45, P < 0.01). Finally, there was no evidence of bottlenecks either at the population level or overall. We conclude that weak population structure occurs among moose in Alaska with population expansion from interior Alaska westward toward the coast.

  20. Photothermal characterization of thermally treated shells of Strombus Gigas

    NASA Astrophysics Data System (ADS)

    Hernández-Ayala, A.; Quintana, P.; Alvarado-Gil, J. J.; Aldana, D.

    2005-06-01

    The thermal properties of the marine shells of the mollusk Strombus gigas are studied using photoacoustic techniques. In order to generate changes in the layered structure of the shells, they were thermally treated in the range from ambient temperature up to 400ºC. Our results show that the thermal diffusivity and conductivity have a maximum at 200ºC due to the degradation of the organic matrix. At higher temperatures the thermal diffusivity and conductivity decrease due to the calcium carbonate structural phase transition from aragonite to calcite.

  1. Mitochondrial genome of the endangered marine gastropod Strombus gigas Linnaeus, 1758 (Mollusca: Gastropoda).

    PubMed

    Márquez, Edna J; Castro, Erick R; Alzate, Juan F

    2016-01-01

    The queen conch Strombus gigas is an endangered marine gastropod of significant economic importance across the Greater Caribbean region. This work reports for the first time the complete mitochondrial genome of S. gigas, obtained by FLX 454 pyrosequencing. The mtDNA genome encodes for 13 proteins, 22 tRNAs and 2 ribosomal RNAs. In addition, the coding sequences and gene synteny were similar to other previously reported mitogenomes of gastropods.

  2. Habitat suitability and conservation of the giant gartersnake (Thamnophis gigas) in the Sacramento Valley of California

    USGS Publications Warehouse

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2010-01-01

    Resource managers often have little information regarding the habitat requirements and distribution of rare species. Factor analysis-based habitat suitability models describe the ecological niche of a species and identify locations where these conditions occur on the landscape using existing occurrence data.We used factor analyses to assess the suitability of habitats for Thamnophis gigas (Giant Gartersnake), a rare, threatened species endemic to the Central Valley of California, USA, and to map the locations of habitat suitable for T. gigas in the Sacramento Valley. Factor analyses indicated that the niche of T. gigas is composed of sites near rice agriculture with low stream densities. Sites with high canal densities and near wetlands also appeared suitable, but results for these variables were sensitive to potential sampling bias. In the Sacramento Valley, suitable habitats occur primarily in the central portion of the valley floor. Based upon the results of the factor analyses, recovery planning for T. gigas will require an on-the-ground assessment of the current distribution and abundance of T. gigas, maintaining the few remaining natural wetlands and the practice of rice agriculture in the Sacramento Valley, and studying the effects of agricultural practices and land use changes on populations of T. gigas.

  3. Molecular and functional characterization of a fads2 orthologue in the Amazonian teleost, Arapaima gigas.

    PubMed

    Lopes-Marques, Mónica; Ozório, Rodrigo; Amaral, Ricardo; Tocher, Douglas R; Monroig, Óscar; Castro, L Filipe C

    2017-01-01

    The Brazilian teleost Arapaima gigas is an iconic species of the Amazon. In recent years a significant effort has been put into the farming of arapaima to mitigate overfishing threats. However, little is known regarding the nutritional requirements of A. gigas in particular those for essential fatty acids including the long-chain polyunsaturated fatty acids (LC-PUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The ability to biosynthesize LC-PUFA is dependent upon the gene repertoire of fatty acyl desaturases (Fads) and elongases (Elovl), as well as their fatty acid specificities. In the present study we characterized both molecularly and functionally an orthologue of the desaturase fatty acid desaturase 2 (fads2) from A. gigas. The isolated sequence displayed the typical desaturase features, a cytochrome b5-domain with the heme-binding motif, two transmembrane domains and three histidine-rich regions. Functional characterization of A. gigas fads2 showed that, similar to other teleosts, the A. gigas fads2 exhibited a predominant Δ6 activity complemented with some capacity for Δ8 desaturation. Given that A. gigas belongs to one of the oldest teleostei lineages, the Osteoglossomorpha, these findings offer a significant insight into the evolution LC-PUFA biosynthesis in teleosts.

  4. Habitat suitability and conservation of the Giant Gartersnake (Thamnophis gigas) in the Sacramento Valley of California

    USGS Publications Warehouse

    Halstead, B.J.; Wylie, G.D.; Casazza, M.L.

    2010-01-01

    Resource managers often have little information regarding the habitat requirements and distribution of rare species. Factor analysis-based habitat suitability models describe the ecological niche of a species and identify locations where these conditions occur on the landscape using existing occurrence data. We used factor analyses to assess the suitability of habitats for Thamnophis gigas (Giant Gartersnake), a rare, threatened species endemic to the Central Valley of California, USA, and to map the locations of habitat suitable for T. gigas in the Sacramento Valley. Factor analyses indicated that the niche of T. gigas is composed of sites near rice agriculture with low stream densities. Sites with high canal densities and near wetlands also appeared suitable, but results for these variables were sensitive to potential sampling bias. In the Sacramento Valley, suitable habitats occur primarily in the central portion of the valley floor. Based upon the results of the factor analyses, recovery planning for T. gigas will require an on-the-ground assessment of the current distribution and abundance of T. gigas, maintaining the few remaining natural wetlands and the practice of rice agriculture in the Sacramento Valley, and studying the effects of agricultural practices and land use changes on populations of T. gigas. ?? 2010 by the American Society of Ichthyologists and Herpetologists.

  5. Adult Pacific Oyster (Crassostrea gigas) May Have Light Sensitivity

    PubMed Central

    Yang, Yanjian; Li, Zhuang; Guo, Ting; Li, Yongchuan; Wang, Xiaotong

    2015-01-01

    Light-sensitivity is an important aspect of mollusk survival as it plays a vital role in reproduction and predator avoidance. In the Pacific oyster Crassostrea gigas light sensitivity has been demonstrated in the larval stage but has not yet been conclusively demonstrated in adult oysters. In this paper we describe an experiment which was undertaken to determine if adult Pacific oysters were sensitive to light. One LED flashlight was used to shine light onto adult oysters while they were filtering seawater through their shell openings. We found that the degree of opening increased gradually during the light period but rapidly decreased when the flashlight was turned off in the treated group but not in the control group. These results suggest that adult Pacific oyster may be sensitive to light. PMID:26474058

  6. Impact and fracture analysis of fish scales from Arapaima gigas.

    PubMed

    Torres, F G; Malásquez, M; Troncoso, O P

    2015-06-01

    Fish scales from the Amazonian fish Arapaima gigas have been characterised to study their impact and fracture behaviour at three different environmental conditions. Scales were cut in two different directions to analyse the influence of the orientation of collagen layers. The energy absorbed during impact tests was measured for each sample and SEM images were taken after each test in order to analyse the failure mechanisms. The results showed that scales tested at cryogenic temperatures display fragile behaviour, while scales tested at room temperature did not fracture. Different failure mechanisms have been identified, analysed and compared with the failure modes that occur in bone. The impact energy obtained for fish scales was two to three times higher than the values reported for bone in the literature.

  7. Software Supportability Risk Assessment in OT&E (Operational Test and Evaluation): Historical Baselines for Risk Profiles. Volume 1.

    DTIC Science & Technology

    1985-10-07

    ORS OC-ALC 8-52 BNST OC-ALC B-52 FTSS OC-ALC 8-52 MC-1 EXEC 00-ALC B-52 MC-2 EXEC OC-ALC E- 3 INS OC-ALC E-3A OMEGA OC-ALC E-3A SMCP OC-ALC E-3A SRCP OC...293 SOFTIAR SWORTRILITY RISK ASSESSMENT IN OTAin 3 (OPERRTIONAL TEST RIM EVA.. (U) ION CORP RLIIUIERWE ENY TI.f CT9 W-5050T-O- WCMLSSIFIED F2901-U...lb. 1*ESTfl.CTIVI; MA04KING.- N/A None .SECURITY~ CLASSIFICATION AbUTNOAITY 3 . OISRIUUTION/AVAILAUILITY UPF MIORT N/A Unlimited -- O CLASSI P SCAT

  8. Prey escaping wolves, Canis lupus, despite close proximity

    USGS Publications Warehouse

    Nelson, M.E.; Mech, L.D.

    1993-01-01

    We describe attacks by wolf (Canis lupus) packs in Minnesota on a white-tailed deer (Odocoileus virginianus) and a moose (Alces alces) in which wolves were within contact distance of the prey but in which the prey escaped.

  9. Experimental oral transmission of chronic wasting disease to red deer (Cervus elaphus elaphus): Early detection and late stage distribution of protease-resistant prion protein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chronic wasting disease CWD is the transmissible spongiform encephalopathy or prion disease of wild and farmed cervid ruminants, including Rocky Mountain elk (Cervus elaphus nelsoni), white tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), or moose (Alces alces). Reliable data ...

  10. The Trilogy is Complete - GigaGalaxy Zoom Phase 3

    NASA Astrophysics Data System (ADS)

    2009-09-01

    The third image of ESO's GigaGalaxy Zoom project has just been released online, completing this eye-opening dive into our galactic home in outstanding fashion. The latest image follows on from views, released over the last two weeks, of the sky as seen with the unaided eye and through an amateur telescope. This third instalment provides another breathtaking vista of an astronomical object, this time a 370-million-pixel view of the Lagoon Nebula of the quality and depth needed by professional astronomers in their quest to understand our Universe. The newly released image extends across a field of view of more than one and a half square degree - an area eight times larger than that of the full Moon - and was obtained with the Wide Field Imager attached to the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. This 67-million-pixel camera has already created several of ESO's iconic pictures. The intriguing object depicted here - the Lagoon Nebula - is located four to five thousand light-years away towards the constellation of Sagittarius (the Archer). The nebula is a giant interstellar cloud, 100 light-years across, where stars are forming. The scattered dark patches seen all over the nebula are huge clouds of gas and dust that are collapsing under their own weight and which will soon give birth to clusters of young, glowing stars. Some of the smallest clouds are known as "globules" and the most prominent ones have been catalogued by the astronomer Edward Emerson Barnard. The Lagoon Nebula hosts the young open stellar cluster known as NGC 6530. This is home for 50 to 100 stars and twinkles in the lower left portion of the nebula. Observations suggest that the cluster is slightly in front of the nebula itself, though still enshrouded by dust, as revealed by reddening of the starlight, an effect that occurs when small dust particles scatter light. The name of the Lagoon Nebula derives from the wide lagoon-shaped dark lane located in the middle of the

  11. GaN Initiative for Grid Applications (GIGA)

    SciTech Connect

    Turner, George

    2015-07-03

    For nearly 4 ½ years, MIT Lincoln Laboratory (MIT/LL) led a very successful, DoE-funded team effort to develop GaN-on-Si materials and devices, targeting high-voltage (>1 kV), high-power, cost-effective electronics for grid applications. This effort, called the GaN Initiative for Grid Applications (GIGA) program, was initially made up of MIT/LL, the MIT campus group of Prof. Tomas Palacios (MIT), and the industrial partner M/A Com Technology Solutions (MTS). Later in the program a 4th team member was added (IQE MA) to provide commercial-scale GaN-on-Si epitaxial materials. A basic premise of the GIGA program was that power electronics, for ubiquitous utilization -even for grid applications - should be closer in cost structure to more conventional Si-based power electronics. For a number of reasons, more established GaN-on-SiC or even SiC-based power electronics are not likely to reach theses cost structures, even in higher manufacturing volumes. An additional premise of the GIGA program was that the technical focus would be on materials and devices suitable for operating at voltages > 1 kV, even though there is also significant commercial interest in developing lower voltage (< 1 kV), cost effective GaN-on-Si devices for higher volume applications, like consumer products. Remarkable technical progress was made during the course of this program. Advances in materials included the growth of high-quality, crack-free epitaxial GaN layers on large-diameter Si substrates with thicknesses up to ~5 μm, overcoming significant challenges in lattice mismatch and thermal expansion differences between Si and GaN in the actual epitaxial growth process. Such thick epilayers are crucial for high voltage operation of lateral geometry devices such as Schottky barrier (SB) diodes and high electron mobility transistors (HEMTs). New “Normally-Off” device architectures were demonstrated – for safe operation of power electronics circuits. The trade-offs between lateral and

  12. Cytogenetics of the darkling beetles Zophobas aff. confusus and Nyctobates gigas (Coleoptera, Tenebrionidae).

    PubMed

    Lira-Neto, A C; Silva, G M; Moura, R C; Souza, M J

    2012-08-16

    Males of Zophobas aff. confusus and Nyctobates gigas (Tenebrionidae) collected in the State of Pernambuco, Brazil, were studied through conventional staining, C-banding, silver nitrate impregnation (AgNO₃), and the base specific fluorochromes CMA₃ and DAPI. Z. aff. confusus was found to have 2n = 20 (9+Xyp) while N. gigas exhibited 2n = 18 (8+neoXY). Large pericentromeric blocks of constitutive heterochromatin (CH) were detected throughout the autosomal complement of the two species, except in one autosomal pair of N. gigas in which no heterochromatic block was observed. The sex chromosomes of both species were almost totally heterochromatic. Double staining with CMA₃/DA (distamycin) and DAPI/DA marked CH in Z. aff. confusus. However, DAPI staining was more intense. N. gigas was found to possess blocks of CH-positive CMA₃ and homogeneous DAPI. AgNO₃ staining also revealed differences between the two species. In Z. confusus an NOR was observed in the sexual bivalent Xyp and N. gigas was found to have an autosomal NOR.

  13. Phylogeny of forkhead genes in three spiralians and their expression in Pacific oyster Crassostrea gigas

    NASA Astrophysics Data System (ADS)

    Yang, Mei; Xu, Fei; Liu, Jun; Que, Huayong; Li, Li; Zhang, Guofan

    2014-11-01

    The Fox genes encode a group of transcription factors that contain a forkhead domain, which forms a structure known as a winged helix. These transcription factors play a crucial role in several key biological processes, including development. High-degree identity in the canonical forkhead domain has been used to divide Fox proteins into 23 families (FoxA to FoxS). We surveyed the genome of three spiralians, the oyster Crassostrea gigas, the limpet Lottia gigantea, and the annelid Capitella teleta. We identified 25 C. gigas fox genes, 21 L. gigantea fox genes, and 25 C. teleta fox genes. The C. gigas fox and L. gigantea fox genes represented 19 of the 23 families, whereas FoxI, Q1, R, and S were missing. The majority of the Fox families were observed within the C. teleta fox genes, with the exception of FoxR and S. In addition, the foxAB-like gene, foxY-like gene, and foxH gene were also present in the three genomes. The conserved FoxC-FoxL1 cluster, observed in mammals, was also found in C. gigas. The diversity of temporal expression patterns observed across the developmental process implies the C. gigas fox genes exert a wide range of functions. Further functional studies are required to gain insight into the evolution of Fox genes in bilaterians.

  14. The GigaFitter: Performance at CDF and Perspectives for Future Applications

    NASA Astrophysics Data System (ADS)

    Amerio, S.; Annovi, A.; Bettini, M.; Bucciantonio, M.; Catastini, P.; Crescioli, F.; Dell'Orso, M.; Giannetti, P.; Lucchesi, D.; Nicoletto, M.; Piendibene, M.; Volpi, G.

    2010-04-01

    The Silicon Vertex Trigger (SVT) is a processor developed at CDF experiment to perform online fast and precise track reconstruction. SVT is made of two pipelined processors, the Associative Memory, finding low precision tracks, and the Track Fitter, refining the track quality whith high precision fits. We will describe the architecture and the performances of a next generation track fitter, the GigaFitter, developed to reduce the degradation of the SVT efficiency due to the increasing instantaneous luminosity. The GigaFitter reduces the track parameter reconstruction to a few clock cycles and can perform many fits in parallel, thus allowing high resolution tracking at very high rate. The core of the GigaFitter is implemented in a modern Xilinx Virtex-5 FPGA chip, rich in powerful DSP arrays. The FPGA is housed on a mezzanine board which receives the data from a subset of the tracking detector and transfers the fitted tracks to a Pulsar motherboard for the final corrections. Instead of the current 12 boards, one per sector of the detector, the final system will be much more compact, consisting of a single GigaFitter Pulsar board equipped with four mezzanine cards receiving the data from the entire tracking detector. Moreover, the GigaFitter modular structure is adequate to scale for much better performances and is general enough to be easily adapted to future High Energy Physics (HEP) experiments and applications outside HEP.

  15. Technology Insertion (TI)/Industrial Process Improvement (IPI). Task Order no. 1 (Misc Manufacturing). Book 2. Database Documentation Book for OO-ALC MANPWW. Analysis of the 80/20 Listing

    DTIC Science & Technology

    1989-12-15

    CCNTA:NED ’IN THE BASIC TrECHNICAL ORDER (T.0.) AND I ,(. • S.LSPFI..PEMENTS REFERENCED IN BLOCK 8 01: THIS AI LC FORM 958, ’H: ______-_________ !PtF...89) 9 0z P co I- j CO~ z Distrbutisn ctptr A. A-p oived t r -"Ib~ lc relear 9162 c~Snb~tOI ~91-02828 DISCLAIMER NOTICE THIS DOCUMENT IS BEST QUALITY...m 0 lo "a 0 MN*N"" 0od ft0 goo 00o0 co0oa 08 0 000 0000 go0 0 c 888000 coo 0 a0000 L5Z- AI 01000 00 00 00000 00 0 0 000 4AU~ 0N 0 C C* 1. 0nj04uN M-4

  16. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Volume 3. OC-ALC Book 1 of 2. Revision A. Contract Summary Report and Quick Fix Plan

    DTIC Science & Technology

    1989-12-15

    ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L9) 6.6-11 6.7.2-1 MATPCB L4 (23) TAGUCHI ORTHOGONAL ARRAY THROUGHPUT EXPERIMENTAL...RESULTS - FY 88 6.7-13 6.7.2-2 ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L4) 6.7-14 6.7.4-1 SUMMARY OF INVESTMENT COST AND...6.14-13 6.14.2-2 ANALYSIS OF EXPERIMENTAL FLOW TIME AVERAGES USING TAGUCHI METHOD (L4 ) 6.14-15 6.15.2-1 L4 TAGUCHI ORTHOGONAL ARRAY EXPERIMENTAL RESULTS

  17. Final Report for CRADA Agreement , AL-C-2006-01 with Microsens Biotechnologies: Detection of the Abnormal Prion Protein in Blood by Improving the Extraction of this Protein

    SciTech Connect

    Schmerr, Mary Jo

    2009-03-31

    Several conditions were examined to optimize the extraction protocol using Seprion beads for the abnormal prion protein. Different combinations of water, hexafluro-2-propanol and formic acid were used. The results of these extraction protocols showed that the magnetic beads coated with Seprion reagents were subject to degradation, themselves, when the extraction conditions that would solubilize the abnormal prion protein were used. These compounds caused interference in the immunoassay for the abnormal prion protein and rendered these protocols incompatible with the assay systems. In an attempt to overcome this problem, another approach was then used. The coated beads were used as an integral part of the assay platform. After washing away denaturing agents, the beads with the 'captured' abnormal prion were incubated directly in the immunoassay, followed by analysis by the capillary electrophoresis. When a capillary electrophoresis electro-kinetic separation was attempted, the beads disturbed the analysis making it impossible to interpret. A pressure separation method was then developed for capillary electrophoresis analysis. When 20 samples, 5 of which were positive were analyzed, the assay identified 4 of the 5 positives and had no false positives. When a larger number of samples were analyzed the results were not as good - there were false positives and false negatives. It was then observed that the amount of beads that were loaded was dependent upon how long the beads were allowed to settle before loading them into the capillary. This resulted in unacceptable variations in the results and explained that when large numbers of samples were evaluated the results were not consistent. Because the technical difficulties with using the Seprion beads could not be overcome at this time, another approach is underway that is outside of the scope of this CRADA. No further agreements have been developed. Because the results were not favorable, no manuscripts were written nor intellectual property developed.

  18. Technology Insertion (TI)/Industrial Process Improvement (IPI). Task Order no. 1 (Misc Manufacturing). Book 3. Database Documentation Book for OO-ALC MANPWW. Main Landing Gear Except C5 - WCD’s

    DTIC Science & Technology

    1989-12-15

    DATE 3 . REPORT rYPE AND DATES COVERED 115Dc89, Aug 88 - Dec 89 4 . TITLE AND SUBTITLE Technology insertion (TI)/Industrial 5. FUNDING NUMBERS Process...NUMBEROFPAGES WHICH DO NOT REPRODUCE LEGIBLY. _ft -’, ; T-,O. 4S1-57- 3 30 34 36 1 Is 2--2 422 IQ2 ~31 c~~ 44 ~’ 45 o31 41 262 53 550 27 6 65 26 O3 4 66’A...Packing 108. Tube 3 . Washer 53. Ring 108A. Packing, 0-ring 4 . Bolt 54. Rod 1086. Ring Backup 5. Pin 55. Tube 109. Tube 6. Nut 56. Washer 109A. Packing O

  19. Technology Insertion-Engineering Services Process Characterization. Task Order No. 1. Book 2 of 5. Database Documentation Book. OO-ALC MANPRA (C5 Main Landing Gear - WCD’S)

    DTIC Science & Technology

    1989-12-15

    P ..... 21 IA tTNTO @A1P OP*AINIIITN C INTR/AI 3 OUET $ DIPTH FNCINLAC lb ____ __ coal_ a...u40 0. ;-w~~4 U n rvz tn 40’- ___ ___ __ ___ 0 co ’-9 0 - un- ’ p ~~0 01- (’ -J-J _jW J0 𔃽< o O.fl I-. 8 - EU Li4D~~ cc -F- r-- 00 CL cL a--L Cc LU zz...Aft Strut Aumbly (Sheet 14 of 18) 2-126 T.O. 4S1-93-4 389 E- ) 389A 3896 -s CN;,~Z.AA$. elUSE P N 4G�!; rA SC,- wir - TI-S CO)NFIGUAATICN.

  20. Crassostrea gigas oysters as a shrimp farm bioindicator of white spot syndrome virus.

    PubMed

    Vazquez-Boucard, C; Escobedo-Fregoso, C; Duran-Avelar, Ma de J; Mercier, L; Llera-Herrera, R; Escobedo-Bonilla, C; Vibanco-Perez, N

    2012-04-26

    This study explored whether Crassostrea gigas oysters can be used as a bioindicator of white spot syndrome virus (WSSV) in shrimp farm water canals. Bioassays showed that C. gigas can accumulate WSSV in their gills and digestive glands but do not become infected, either by exposure to seawater containing WSSV or by cohabitation with infected shrimp. The use of a WSSV nested PCR to screen oysters placed in water canals at the entry of a shrimp farm allowed WSSV to be detected 16 d prior to the disease occurring. The finding that C. gigas can concentrate small amounts of WSSV present in seawater without being harmed makes it an ideal sentinel species at shrimp farms.

  1. Overexpression of cinnamate 4-hydroxylase gene enhances biosynthesis of decursinol angelate in Angelica gigas hairy roots.

    PubMed

    Park, Nam Il; Park, Jee Hee; Park, Sang Un

    2012-02-01

    Angelica gigas is a medicinal plant that produces pyranocoumarins, including decursin (D) and decursinol angelate (DA), which have neuroprotective, anticancer, and antiandrogenic effects. In this study, the coumarin biosynthetic pathway was engineered to increase the production of DA. Specifically, a vector was constructed which contained the A. gigas phenylalanine ammonia-lyase (AgPAL) and cinnamate 4-hydroxylase (AgC4H) genes that were driven by the cauliflower mosaic virus (CaMV) 35S promoter. Transgenic hairy roots that overexpressed AgPAL or AgC4H genes were obtained by using an Agrobacterium rhizogenes-mediated transformation system. Among them, only AgC4H-transgenic hairy root lines produced more DA than control transgenic hairy root lines. The enhanced gene expression corresponded to elevated C4H activities. This study showed the importance of C4H in the production of DA in A. gigas hairy root culture.

  2. Terrestrial ecology of semi-aquatic giant gartersnakes (Thamnophis gigas)

    USGS Publications Warehouse

    Halstead, Brian J.; Skalos, Shannon M.; Wylie, Glenn D.; Casazza, Michael L.

    2015-01-01

    Wetlands are a vital component of habitat for semiaquatic herpetofauna, but for most species adjacent terrestrial habitats are also essential. We examined the use of terrestrial environments by Giant Gartersnakes (Thamnophis gigas) to provide behavioral information relevant to conservation of this state and federally listed threatened species. We used radio telemetry data collected 1995–2011 from adults at several sites throughout the Sacramento Valley, California, USA, to examine Giant Gartersnake use of the terrestrial environment. We found Giant Gartersnakes in terrestrial environments more than half the time during the summer, with the use of terrestrial habitats increasing to nearly 100% during brumation. While in terrestrial habitats, we found Giant Gartersnakes underground more than half the time in the early afternoon during summer, and the probability of being underground increased to nearly 100% of the time at all hours during brumation. Extreme temperatures also increased the probability that we would find Giant Gartersnakes underground. Under most conditions, we found Giant Gartersnakes to be within 10 m of water at 95% of observations. For females during brumation and individuals that we found underground, however, the average individual had a 10% probability of being located > 20 m from water. Individual variation in each of the response variables was extensive; therefore, predicting the behavior of an individual was fraught with uncertainty. Nonetheless, our estimates provide resource managers with valuable information about the importance of protecting and carefully managing terrestrial habitats for conserving a rare semiaquatic snake.

  3. Stress-induced immune changes in the oyster Crassostrea gigas.

    PubMed

    Lacoste, Arnaud; Malham, Shelagh K; Gélébart, Florence; Cueff, Anne; Poulet, Serge A

    2002-01-01

    Information concerning the effect of stress on invertebrate immune functions are scarce. The present study investigated the consequences of a 15-min mechanical disturbance on immune parameters in oysters Crassostrea gigas. As indicated by noradrenaline and dopamine measurements, the mechanical disturbance caused a transient state of stress in oysters. The number of circulating hemocytes, the migratory and phagocytic activities and reactive oxygen species production of hemocytes were measured before, during and after application of the stressor. Results show that all immune functions were significantly downregulated during stress and a transient period of immunostimulation was observed 30-240 min after the end of the disturbance. Taken together, these results suggest that stress can exert a profound influence on oyster immune functions and they may explain why stress and the outbreak of disease are often linked in shellfish culture. Furthermore, the present study strongly suggests that checking the stress status of animals may be necessary to avoid biases when studying oyster immune responses in vivo.

  4. Study of atrazine effects on Pacific oyster, Crassostrea gigas, haemocytes.

    PubMed

    Gagnaire, B; Renault, T; Bouilly, K; Lapegue, S; Thomas-Guyon, H

    2003-01-01

    Shellfish farming is an important economic activity around the world. This activity often takes place in areas subjected to various recurring pollutions. The recrudescent use of herbicides in agriculture including atrazine implies pollutant transfer towards aquatic environment in estuarine areas. Harmful effects of such substances on animals in marine environment, particularly on cultured bivalves, are poorly documented. Bivalve molluscs such as mussels and oysters have been postulated as ideal indicator organisms because of their way of life. They filter large volumes of seawater and may therefore accumulate and concentrate contaminants within their tissues. Moreover, development of techniques allowing effect analysis of such compounds on bivalve biology may lead to the development of diagnosis tools adapted to analyze pollutant transfer towards estuarine areas. In this context, influence of atrazine on defence mechanisms was analyzed in Pacific oysters, Crassostrea gigas. Atrazine was tested in vitro and in vivo on oyster haemocytes, and its effects were analyzed by flow cytometry. Haemocyte viability, cell cycle and cellular activities were monitored. Atrazine induced no significant effect in oyster under tested conditions except for peroxidase activity.

  5. Comparative energetics of the giant hummingbird (Patagona gigas).

    PubMed

    Fernández, María José; Dudley, Robert; Bozinovic, Francisco

    2011-01-01

    Hummingbirds (family Trochilidae) represent an extreme outcome in vertebrate physiological design and are the only birds capable of sustained hovering. The giant hummingbird (Patagona gigas) is the largest trochilid, with a mass of ~20 g, and is found over an altitudinal range from 0 to 4,500 m above sea level. We report here measurements of daily, basal, and hovering rates of oxygen consumption in the giant hummingbird; compare these values with data from smaller hummingbirds; and assess overall metabolic and allometric limits to trochilid body size. The sustained metabolic scope (i.e., the ratio of daily energy expenditure to basal metabolic rate) in the giant hummingbird is higher than that in smaller hummingbirds but lies below a proposed theoretical maximum value for endotherms. Scaling exponents in the allometric relationships for different modes of energetic expenditure were comparable, suggesting that the giant hummingbird, although a clear outlier in terms of body size, does not obviously deviate from metabolic relationships derived from other trochilid taxa.

  6. Anatomical distribution of sterols in oysters (Crassostrea gigas).

    PubMed

    Gordon, D T; Collins, N

    1982-11-01

    Oysters (Crassostrea gigas) contain at least 8 predominant sterols as determined by gas liquid chromatography and a modified Liebermann-Burchard reaction. These sterols and the average amount found in mg/100 are: C26-sterol (22-trans-24-norcholesta-5, 22-diene-3 beta-ol), 19.1; 22-dehydrocholesterol, 15.1; cholesterol, 46.8; brassicasterol, 27.2; delta 5,7-sterols (i.e., 7-dehydrocholesterol) 22.5; 24-methylenecholesterol 29.1; 24-ethylcholesta-5,22-diene-3 beta-ol, 1.2; and 24-ethylcholesta-5-en-3 beta-ol, 12.7. The distribution of these sterols appears uniform (r2 = 0.938) between 5 major organs of the oyster. The percent body mass vs percent total sterols in these 5 organs are: mantle 44.1--41.4; visceral mass 30.3--36.7; gills 13.2--11.7; adductor muscle 8.3--3.7; and labial palps 4.2--6.5. The possible sources of these sterols are discussed.

  7. Genome sequence of the model sulfate reducer Desulfovibrio gigas: a comparative analysis within the Desulfovibrio genus.

    PubMed

    Morais-Silva, Fabio O; Rezende, Antonio Mauro; Pimentel, Catarina; Santos, Catia I; Clemente, Carla; Varela-Raposo, Ana; Resende, Daniela M; da Silva, Sofia M; de Oliveira, Luciana Márcia; Matos, Marcia; Costa, Daniela A; Flores, Orfeu; Ruiz, Jerónimo C; Rodrigues-Pousada, Claudina

    2014-08-01

    Desulfovibrio gigas is a model organism of sulfate-reducing bacteria of which energy metabolism and stress response have been extensively studied. The complete genomic context of this organism was however, not yet available. The sequencing of the D. gigas genome provides insights into the integrated network of energy conserving complexes and structures present in this bacterium. Comparison with genomes of other Desulfovibrio spp. reveals the presence of two different CRISPR/Cas systems in D. gigas. Phylogenetic analysis using conserved protein sequences (encoded by rpoB and gyrB) indicates two main groups of Desulfovibrio spp, being D. gigas more closely related to D. vulgaris and D. desulfuricans strains. Gene duplications were found such as those encoding fumarate reductase, formate dehydrogenase, and superoxide dismutase. Complexes not yet described within Desulfovibrio genus were identified: Mnh complex, a v-type ATP-synthase as well as genes encoding the MinCDE system that could be responsible for the larger size of D. gigas when compared to other members of the genus. A low number of hydrogenases and the absence of the codh/acs and pfl genes, both present in D. vulgaris strains, indicate that intermediate cycling mechanisms may contribute substantially less to the energy gain in D. gigas compared to other Desulfovibrio spp. This might be compensated by the presence of other unique genomic arrangements of complexes such as the Rnf and the Hdr/Flox, or by the presence of NAD(P)H related complexes, like the Nuo, NfnAB or Mnh.

  8. Genome sequence of the model sulfate reducer Desulfovibrio gigas: a comparative analysis within the Desulfovibrio genus*

    PubMed Central

    Morais-Silva, Fabio O; Rezende, Antonio Mauro; Pimentel, Catarina; Santos, Catia I; Clemente, Carla; Varela–Raposo, Ana; Resende, Daniela M; da Silva, Sofia M; de Oliveira, Luciana Márcia; Matos, Marcia; Costa, Daniela A; Flores, Orfeu; Ruiz, Jerónimo C; Rodrigues-Pousada, Claudina

    2014-01-01

    Desulfovibrio gigas is a model organism of sulfate-reducing bacteria of which energy metabolism and stress response have been extensively studied. The complete genomic context of this organism was however, not yet available. The sequencing of the D. gigas genome provides insights into the integrated network of energy conserving complexes and structures present in this bacterium. Comparison with genomes of other Desulfovibrio spp. reveals the presence of two different CRISPR/Cas systems in D. gigas. Phylogenetic analysis using conserved protein sequences (encoded by rpoB and gyrB) indicates two main groups of Desulfovibrio spp, being D. gigas more closely related to D. vulgaris and D. desulfuricans strains. Gene duplications were found such as those encoding fumarate reductase, formate dehydrogenase, and superoxide dismutase. Complexes not yet described within Desulfovibrio genus were identified: Mnh complex, a v-type ATP-synthase as well as genes encoding the MinCDE system that could be responsible for the larger size of D. gigas when compared to other members of the genus. A low number of hydrogenases and the absence of the codh/acs and pfl genes, both present in D. vulgaris strains, indicate that intermediate cycling mechanisms may contribute substantially less to the energy gain in D. gigas compared to other Desulfovibrio spp. This might be compensated by the presence of other unique genomic arrangements of complexes such as the Rnf and the Hdr/Flox, or by the presence of NAD(P)H related complexes, like the Nuo, NfnAB or Mnh. PMID:25055974

  9. Literature review of giant gartersnake (Thamnophis gigas) biology and conservation

    USGS Publications Warehouse

    Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.

    2015-08-03

    This report reviews the available literature on giant gartersnakes (Thamnophis gigas) to compile existing information on this species and identify knowledge gaps that, if addressed, would help to inform conservation efforts for giant gartersnakes.  Giant gartersnakes comprise a species of semi-aquatic snake precinctive to wetlands in the Central Valley of California.  The diversion of surface water and conversion of wetlands to agricultural and other land uses resulted in the loss of more than 90 percent of natural giant gartersnake habitats.  Because of this habitat loss, giant gartersnakes are now listed by the United States and California Endangered Species Acts as Threatened.  Most extant populations occur in the rice-growing regions of the Sacramento Valley, which comprises the northern portion of the giant gartersnake’s former range.  The huge demand for water in California for agriculture, industry, recreation, and other human consumption, combined with periodic severe drought, places remaining giant gartersnake habitats at increased risk of degradation and loss.  This literature review summarizes the available information on giant gartersnake distribution, habitat relations, behavior, demography, and other aspects of its biology relevant to conservation.  This information is then compiled into a graphical conceptual model that indicates the importance of different aspects of giant gartersnake biology for maintaining positive population growth, and identifies those areas for which important information relevant for conservation is lacking.  Directing research efforts toward these aspects of giant gartersnake ecology will likely result in improvements to conserving this unique species while meeting the high demands for water in California.

  10. Successful cryopreservation of Pacific oyster (Crassostrea gigas) oocytes.

    PubMed

    Tervit, H R; Adams, S L; Roberts, R D; McGowan, L T; Pugh, P A; Smith, J F; Janke, A R

    2005-10-01

    Protocols for cryopreservation of sperm and oocytes would provide the ultimate control over parental crosses in selective breeding programmes. Sperm freezing is routine for many species, but oocyte freezing remains problematic, with virtually zero success in aquatic species to date. This paper describes the development of a successful protocol for cryopreserving high concentrations of Pacific oyster (Crassostrea gigas) oocytes. Ethylene glycol (10%) and dimethyl sulfoxide (15%) were found to be the most effective cryoprotectants resulting in post-thaw fertilization rates of 51.0+/-8.0 and 45.1+/-8.3%, respectively. Propylene glycol was less effective and methanol resulted in zero fertilization post-thaw. The use of Milli-Q water rather than seawater as a base medium significantly improved fertilization (20.4+/-3.0 and 8.7+/-2.2%, respectively) as did the inclusion of a 5 min isothermal hold at -10 or -12 degrees C (35.9+/-5.0 and 31.9+/-4.6%, respectively). The optimal cooling rate post-hold was 0.3 degrees C min(-1), with virtually zero post-thaw fertilization with cooling rates of 3 and 6 degrees C min(-1). Using an optimized protocol, post-thaw fertilization rates for oocytes from eight individual females ranged from 0.8 to 74.5% and D-larval yields from 0.1 to 30.1%. For three individuals, larvae were reared through to spat. Development of D-larvae to eyed larvae and spat was similar for larvae produced from unfrozen (24.8+/-4.1% developed to eyed larvae and 16.5+/-3.2% to spat) and cryopreserved (28.4+/-0.6 and 18.7+/-0.5%, respectively) oocytes. The ability to cryopreserve large quantities of oyster oocytes represents a major advance in cryobiology and selective breeding.

  11. Functional characterisation of phagocytes in the Pacific oyster Crassostrea gigas

    PubMed Central

    Jiang, Shuai; Jia, Zhihao; Zhang, Tao; Wang, Lingling; Qiu, Limei; Sun, Jinsheng

    2016-01-01

    Invertebrates lack canonical adaptive immunity and mainly rely on innate immune system to fight against pathogens. The phagocytes, which could engulf and kill microbial pathogens, are likely to be of great importance and have to undertake significant roles in invertebrate immune defense. In the present study, flow cytometry combined with histological and lectin staining was employed to characterise functional features of phagocytes in the Pacific oyster Crassostrea gigas. Based on the cell size and cellular contents, haemocytes were categorised into three cell types, i.e., granulocytes, semigranulocytes and agranulocytes. Agranulocytes with smaller cell volume and lower cytoplasmic-to-nuclear ratio did not show phagocytic activity, while semigranulocytes and agranulocytes exhibited larger cell volume, higher cytoplasmic-to-nuclear ratio and phagocytic activity. In addition, granulocytes with higher side scatter (SSC) exhibited higher phagocytic activity than that of semigranulocytes. When β-integrin and lectin-like receptors were blocked by RGD tripeptide and carbohydrates, respectively, the phagocytic activity of both granulocytes and semigranulocytes was significantly inhibited, indicating that β-integrin and certain lectin-like receptors were involved in phagocytosis towards microbes. Moreover, lipopolysaccharide but not peptidylglycan could enhance phagocytic activity of granulocytes and semigranulocytes towards Vibrio splendidus and Staphylococcus aureus. Lectin staining analysis revealed that Lycopersicon esculentum lectin (LEL), binding the epitope polylactosamine, was highly distributed on the extracellular cell surface of phagocytes, and could be utilized as a potential molecular marker to differentiate phagocytes from non-phagocytic haemocytes. The results, collectively, provide knowledge on the functional characters of oyster phagocytes, which would contribute to deep investigation of cell typing and cellular immunity in bivalves. PMID:27994957

  12. Effects of gamma irradiation on the yields of volatile extracts of Angelica gigas Nakai

    NASA Astrophysics Data System (ADS)

    Seo, Hye-Young; Kim, Jun-Hyoung; Song, Hyun-Pa; Kim, Dong-Ho; Byun, Myung-Woo; Kwon, Joog-Ho; Kim, Kyong-Su

    2007-11-01

    The study was carried out to determine the effects of gamma irradiation on the volatile flavor components including essential oils, of Angelica gigas Nakai. The volatile organic compounds from non- and irradiated A. gigas Nakai at doses of 1, 3, 5, 10 and 20 kGy were extracted by a simultaneous steam distillation and extraction (SDE) method and identified by GC/MS analysis. A total of 116 compounds were identified and quantified from non- and irradiated A. gigas Nakai. The major volatile compounds were identified 2,4,6-trimethyl heptane, α-pinene, camphene, α-limonene, β-eudesmol, α-murrolene and sphatulenol. Among these compounds, the amount of essential oils in non-irradiated sample were 77.13%, and the irradiated samples at doses of 1, 3, 5, 10 and 20 kGy were 84.98%, 83.70%, 83.94%, 82.84% and 82.58%, respectively. Oxygenated terpenes such as β-eudesmol, α-eudesmol, and verbenone were increased after irradiation but did not correlate with the irradiation dose. The yields of active substances such as essential oil were increased after irradiation; however, the yields of essential oils and the irradiation dose were not correlated. Thus, the profile of composition volatiles of A. gigas Nakai did not change with irradiation.

  13. The Global Invertebrate Genomics Alliance (GIGA): developing community resources to study diverse invertebrate genomes.

    PubMed

    Bracken-Grissom, Heather; Collins, Allen G; Collins, Timothy; Crandall, Keith; Distel, Daniel; Dunn, Casey; Giribet, Gonzalo; Haddock, Steven; Knowlton, Nancy; Martindale, Mark; Medina, Mónica; Messing, Charles; O'Brien, Stephen J; Paulay, Gustav; Putnam, Nicolas; Ravasi, Timothy; Rouse, Greg W; Ryan, Joseph F; Schulze, Anja; Wörheide, Gert; Adamska, Maja; Bailly, Xavier; Breinholt, Jesse; Browne, William E; Diaz, M Christina; Evans, Nathaniel; Flot, Jean-François; Fogarty, Nicole; Johnston, Matthew; Kamel, Bishoy; Kawahara, Akito Y; Laberge, Tammy; Lavrov, Dennis; Michonneau, François; Moroz, Leonid L; Oakley, Todd; Osborne, Karen; Pomponi, Shirley A; Rhodes, Adelaide; Santos, Scott R; Satoh, Nori; Thacker, Robert W; Van de Peer, Yves; Voolstra, Christian R; Welch, David Mark; Winston, Judith; Zhou, Xin

    2014-01-01

    Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from these organisms have been sequenced. We have, therefore, formed a "Global Invertebrate Genomics Alliance" (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture.

  14. The Global Invertebrate Genomics Alliance (GIGA): Developing Community Resources to Study Diverse Invertebrate Genomes

    PubMed Central

    2014-01-01

    Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from these organisms have been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture. PMID:24336862

  15. Range Expansion of Moose in Arctic Alaska Linked to Warming and Increased Shrub Habitat.

    PubMed

    Tape, Ken D; Gustine, David D; Ruess, Roger W; Adams, Layne G; Clark, Jason A

    2016-01-01

    Twentieth century warming has increased vegetation productivity and shrub cover across northern tundra and treeline regions, but effects on terrestrial wildlife have not been demonstrated on a comparable scale. During this period, Alaskan moose (Alces alces gigas) extended their range from the boreal forest into tundra riparian shrub habitat; similar extensions have been observed in Canada (A. a. andersoni) and Eurasia (A. a. alces). Northern moose distribution is thought to be limited by forage availability above the snow in late winter, so the observed increase in shrub habitat could be causing the northward moose establishment, but a previous hypothesis suggested that hunting cessation triggered moose establishment. Here, we use recent changes in shrub cover and empirical relationships between shrub height and growing season temperature to estimate available moose habitat in Arctic Alaska c. 1860. We estimate that riparian shrubs were approximately 1.1 m tall c. 1860, greatly reducing the available forage above the snowpack, compared to 2 m tall in 2009. We believe that increases in riparian shrub habitat after 1860 allowed moose to colonize tundra regions of Alaska hundreds of kilometers north and west of previous distribution limits. The northern shift in the distribution of moose, like that of snowshoe hares, has been in response to the spread of their shrub habitat in the Arctic, but at the same time, herbivores have likely had pronounced impacts on the structure and function of these shrub communities. These northward range shifts are a bellwether for other boreal species and their associated predators.

  16. Range Expansion of Moose in Arctic Alaska Linked to Warming and Increased Shrub Habitat

    PubMed Central

    Tape, Ken D.

    2016-01-01

    Twentieth century warming has increased vegetation productivity and shrub cover across northern tundra and treeline regions, but effects on terrestrial wildlife have not been demonstrated on a comparable scale. During this period, Alaskan moose (Alces alces gigas) extended their range from the boreal forest into tundra riparian shrub habitat; similar extensions have been observed in Canada (A. a. andersoni) and Eurasia (A. a. alces). Northern moose distribution is thought to be limited by forage availability above the snow in late winter, so the observed increase in shrub habitat could be causing the northward moose establishment, but a previous hypothesis suggested that hunting cessation triggered moose establishment. Here, we use recent changes in shrub cover and empirical relationships between shrub height and growing season temperature to estimate available moose habitat in Arctic Alaska c. 1860. We estimate that riparian shrubs were approximately 1.1 m tall c. 1860, greatly reducing the available forage above the snowpack, compared to 2 m tall in 2009. We believe that increases in riparian shrub habitat after 1860 allowed moose to colonize tundra regions of Alaska hundreds of kilometers north and west of previous distribution limits. The northern shift in the distribution of moose, like that of snowshoe hares, has been in response to the spread of their shrub habitat in the Arctic, but at the same time, herbivores have likely had pronounced impacts on the structure and function of these shrub communities. These northward range shifts are a bellwether for other boreal species and their associated predators. PMID:27074023

  17. Seawater temperature effect on metal accumulation and toxicity in the subantarctic Macquarie Island isopod, Exosphaeroma gigas.

    PubMed

    Lewis, Alexander; King, Catherine K; Hill, Nicole A; Cooper, Ashley; Townsend, Ashley T; Mondon, Julie A

    2016-08-01

    Very little is currently known of subantarctic nearshore invertebrates' sensitivity to environmental metals and the role of temperature in this relationship. This study investigated Cu and Zn toxicity in the common subantarctic intertidal isopod, Exosphaeroma gigas, and the influence of temperature on Cu toxicity and bioaccumulation kinetics. Adult E. gigas are insensitive to Cu and Zn at concentrations of 3200 and 7400μg/L respectively in non-renewal tests at 5.5°C (ambient subtidal temperature) over 14days. Under renewed exposures over the same temperature and time period the LC50 for copper was 2204μg/L. A 10-fold increase in Cu body burden occurred relative to zinc, indicating E. gigas has different strategies for regulating the two metals. Copper toxicity and time to mortality both increased with elevated temperature. However, temperature did not significantly affect Cu uptake rate and efflux rate constants derived from biodynamic modelling at lower Cu concentrations. These results may be attributable to E. gigas being an intertidal species with physiological mechanisms adapted to fluctuating environmental conditions. Cu concentrations required to elicit a toxicity response indicates that E. gigas would not be directly threatened by current levels of Cu or Zn present in Macquarie Island intertidal habitats, with the associated elevated temperature fluctuations. This study provides evidence that the sensitivity of this subantarctic intertidal species to metal contaminants is not as high as expected, and which has significance for the derivation of relevant guidelines specific to this distinct subpolar region of the world.

  18. Fishery biology of jumbo flying squid Dosidicus gigas off Costa Rica Dome

    NASA Astrophysics Data System (ADS)

    Chen, Xinjun; Li, Jianghua; Liu, Bilin; Li, Gang; Lu, Huajie

    2014-06-01

    The jumbo flying squid ( Dosidicus gigas) population was surveyed with the help of Chinese squid jigging vessels off the Costa Rica Dome (4°-11°N, 90°-100°W) in 2009 and 2010. The daily catch of D. gigas in the two survey cruises ranged from 0 to 5.5 t and was mostly obtained from the areas bounded by 6°-9°N and 91°-94°W and by 6°30'-7°30'N and 96°-97°W. The sea surface temperature in the areas yielding the most catch ranged from 27.5 to 29°C. The sex ratio of the total catch was 3.75:1 (female: male). The mantle length of the squid ranged from 211 to 355 mm (male) and from 204 to 429 mm (female) with an average of 297.9 and 306.7 mm, respectively. In the relationship of the mantle length (mm) and body weight (g) of the squid, there was no significant difference between sexes. The female and male were at a similar maturity, and most individuals are maturing or have matured with a few females being spent. The size (mantle length) and age at the first sexual maturity were 297 mm and 195 d in females, and less than 211 mm and 130 d in males, respectively. Most of the sampled stomachs (70.6%) had no food remains. The major preys of the squids were fish, cephalopods and crustaceans, with the most abundant Myctophum orientale and D. gigas. The preys in more than 65% of the non-empty sampled stomachs evidenced the cannibalism of D. gigas. The results improved current understanding of the fishery biology of D. gigas off the Costa Rica Dome, which may facilitate the assessment and management of relative fishery resources.

  19. Innovative uses of GigaPan Technology for Onsite and Distance Education

    NASA Astrophysics Data System (ADS)

    Bentley, C.; Schott, R. C.; Piatek, J. L.; Richards, B.

    2013-12-01

    GigaPans are gigapixel panoramic images that can be viewed at a wide range of magnifications, allowing users to explore them in various degrees of detail from the smallest scale to the full image extent. In addition to panoramic images captured with the GigaPan camera mount ('Dry Falls' - http://www.gigapan.com/gigapans/89093), users can also upload annotated images (For example, 'Massanutten sandstone slab with trace fossils (annotated)', http://www.gigapan.com/gigapans/124295) and satellite images (For example, 'Geology vs. Topography - State of Connecticut', http://www.gigapan.com/gigapans/111265). Panoramas with similar topics have been gathered together on the site in galleries, both user-generated and site-curated (For example, http://www.gigapan.com/galleries?categories=geology&page=1). Further innovations in display technology have also led to the development of improved viewers (for example, the annotations in the image linked above can be explored via paired viewers at http://coursecontent.nic.edu/bdrichards/gigapixelimages/callanview) GigaPan panoramas can be created through use of the GigaPan robotic camera mount and a digital camera (different models of the camera mount are available and work with a wide range of cameras). The camera mount can be used to create high-resolution pans ranging in scale from hand sample to outcrop up to landscape via the stitching software included with the robotic mount. The software can also be used to generate GigaPan images from other sources, such as thin section or satellite images, so these images can also be viewed with the online viewer. GigaPan images are typically viewed via a web-based interface that allows the user to interact with the image from the limits of the image detail up to the full panorama. After uploading, information can be added to panoramas with both text captions and geo-referencing (geo-located panoramas can then be viewed in Google Earth). Users can record specific locations and zoom levels in

  20. The Untold Story of Being Designated an Alternate Level of Care Patient

    PubMed Central

    McCloskey, Rose; Jarrett, Pamela; Stewart, Connie

    2015-01-01

    Introduction: Much of the research and policy reports on Alternate Level of Care (ALC) in Canada have focused on the impact ALC has on acute care services. To date, the experiences and opinions of those who must wait in hospital for alternate services have been largely absent from discussions. Method: A qualitative study was conducted with patients and families designated as ALC in one urban and two rural hospitals in Atlantic Canada. Data were analyzed using content analysis. Results: Three themes emerged from the data: a perception of normalcy, being old but not sick and anticipating relocation to another facility. Conclusions: ALC is an important issue for patients and their families. Policy directives aimed at addressing the causes and impacts of ALC, identification and provision of appropriate supportive care in the community and sensitivity to the impact of ALC for individuals designated as ALC are needed. PMID:26571470

  1. Sclerochronology of Holocene oyster shells (Crassostrea gigas) from the West Coast of Bohai Sea, China

    NASA Astrophysics Data System (ADS)

    Fan, C.; Koeniger, P.; Wang, H.; Frechen, M.

    2009-04-01

    Sclerochronology, the study of periodic increments in skeletal organisms, can decipher the life history and environmental records preserved in fossil shells. Although there have been a number of studies that apply isotopic analyses to shells in open ocean and fresh water, investigations for brackish environments are rare. One of the common inhabitants in estuaries is the Crassostrea oyster. Kirby et al. (1998) demonstrated a close correspondence between the ligamental increments of convex and concave bands and yearly ^18O cycles; Andrus and Crowe (2000) found a close correspondence between translucent growth bands on the cross-section of the hinge and yearly ^18O cycles. They conclude that the morphological features on hinge and growth bands on the cross-section are formed annually and can be used to determine accurately age and growth rate in this species. However, Surge et al. (2001) could not find that these morphologic features have seasonal significance in the C. virginica shells. Therefore, these concave ridges are not reliable independent proxies of seasonality. These studies were carried out with C. virginica shells; none was studied with nature C. gigas, which was widely distributed along the Pacific coastal area. C. gigas has been introduced from its native home to all over the world, ranging from North America to Australia and Europe; it has become an important commercial harvest in many of these places. Buried Holocene oyster shells of C. gigas were sampled from a huge buried oyster reef on the West of Bohai Sea, China. One of these shells was selected for high resolution micro-sampling and stable isotope analyses testing the assumption that C. gigas ligamental increments are annual in nature. We analyzed 236 consecutive samples from the shell to show that morphologic features both on hinge and cross-section are annual by comparing them to the ^18O profiles. We tested the assumption that the morphologic features of C.gigas are delineated by convex tops

  2. Generation and analysis of a 29,745 unique Expressed Sequence Tags from the Pacific oyster (Crassostrea gigas) assembled into a publicly accessible database: the GigasDatabase

    PubMed Central

    2009-01-01

    Background Although bivalves are among the most-studied marine organisms because of their ecological role and economic importance, very little information is available on the genome sequences of oyster species. This report documents three large-scale cDNA sequencing projects for the Pacific oyster Crassostrea gigas initiated to provide a large number of expressed sequence tags that were subsequently compiled in a publicly accessible database. This resource allowed for the identification of a large number of transcripts and provides valuable information for ongoing investigations of tissue-specific and stimulus-dependant gene expression patterns. These data are crucial for constructing comprehensive DNA microarrays, identifying single nucleotide polymorphisms and microsatellites in coding regions, and for identifying genes when the entire genome sequence of C. gigas becomes available. Description In the present paper, we report the production of 40,845 high-quality ESTs that identify 29,745 unique transcribed sequences consisting of 7,940 contigs and 21,805 singletons. All of these new sequences, together with existing public sequence data, have been compiled into a publicly-available Website http://public-contigbrowser.sigenae.org:9090/Crassostrea_gigas/index.html. Approximately 43% of the unique ESTs had significant matches against the SwissProt database and 27% were annotated using Gene Ontology terms. In addition, we identified a total of 208 in silico microsatellites from the ESTs, with 173 having sufficient flanking sequence for primer design. We also identified a total of 7,530 putative in silico, single-nucleotide polymorphisms using existing and newly-generated EST resources for the Pacific oyster. Conclusion A publicly-available database has been populated with 29,745 unique sequences for the Pacific oyster Crassostrea gigas. The database provides many tools to search cleaned and assembled ESTs. The user may input and submit several filters, such as

  3. Cytochemical characterization of yolk granule acid phosphatase during early development of the oyster Crassostrea gigas (Thunberg)

    NASA Astrophysics Data System (ADS)

    Wang, Yiyan; Sun, Hushan; Wang, Yanjie; Yan, Dongchun; Wang, Lei

    2015-03-01

    In this study, a cytochemical method and transmission electron microscopy was used to examine acid phosphatase activities of yolk granules throughout the early developmental stages of the Pacific oyster Crassostrea gigas. This study aimed to investigate the dynamic change of yolk granule acid phosphatase, and the mechanisms underlying its involvement in yolk degradation during the early developmental stages of molluscs. Three types of yolk granules (YGI, YGII, and YGIII) that differed in electron density and acid phosphatase reaction were identified in early cleavage, morula, blastula, gastrula, trochophore, and veliger stages. The morphological heterogeneities of the yolk granules were related to acid phosphatase activity and degrees of yolk degradation, indicating the association of acid phosphatase with yolk degradation in embryos and larvae of molluscs. Fusion of yolk granules was observed during embryogenesis and larval development of C. gigas. The fusion of YGI (free of acid phosphatase reaction) with YGII (rich in acid phosphatase reaction) could be the way by which yolk degradation is triggered.

  4. Size increment of jumbo flying squid Dosidicus gigas mature females in Peruvian waters, 1989-2004

    NASA Astrophysics Data System (ADS)

    Argüelles, Juan; Tafur, Ricardo; Taipe, Anatolio; Villegas, Piero; Keyl, Friedeman; Dominguez, Noel; Salazar, Martín

    2008-10-01

    Changes in population structure of the jumbo flying squid Dosidicus gigas in Peruvian waters were studied based on size-at-maturity from 1989 to 2004. From 1989 to 1999, mature squid belonging to the medium-sized group prevailed, but from 2001 on, mature squids were larger. This change is not related to the changes in sea surface temperature and we hypothesized that it was caused by the population increase of mesopelagic fishes as prey.

  5. Results and insights from the NCSU Insect Museum GigaPan project.

    PubMed

    Bertone, Matthew A; Blinn, Robert L; Stanfield, Tanner M; Dew, Kelly J; Seltmann, Katja C; Deans, Andrew R

    2012-01-01

    Pinned insect specimens stored in museum collections are a fragile and valuable resource for entomological research. As such, they are usually kept away from viewing by the public and hard to access by experts. Here we present a method for mass imaging insect specimens, using GigaPan technology to achieve highly explorable, many-megapixel panoramas of insect museum drawers. We discuss the advantages and limitations of the system, and describe future avenues of collections research using this technology.

  6. Giga-z: A 100,000 Object Superconducting Spectrophotometer for LSST Follow-up

    NASA Astrophysics Data System (ADS)

    Marsden, Danica W.; Mazin, Benjamin A.; O'Brien, Kieran; Hirata, Chris

    2013-09-01

    We simulate the performance of a new type of instrument, a Superconducting Multi-Object Spectrograph (SuperMOS), that uses microwave kinetic inductance detectors (MKIDs). MKIDs, a new detector technology, feature good quantum efficiency in the UVOIR, can count individual photons with microsecond timing accuracy, and, like X-ray calorimeters, determine their energy to several percent. The performance of Giga-z, a SuperMOS designed for wide field imaging follow-up observations, is evaluated using simulated observations of the COSMOS mock catalog with an array of 100,000 R 423 nm = E/ΔE = 30 MKID pixels. We compare our results against a simultaneous simulation of LSST observations. In 3 yr on a dedicated 4 m class telescope, Giga-z could observe ≈2 billion galaxies, yielding a low-resolution spectral energy distribution spanning 350-1350 nm for each; 1000 times the number measured with any currently proposed LSST spectroscopic follow-up, at a fraction of the cost and time. Giga-z would provide redshifts for galaxies up to z ≈ 6 with magnitudes mi <~ 25, with accuracy σΔz/(1 + z) ≈ 0.03 for the whole sample, and σΔz/(1 + z) ≈ 0.007 for a select subset. We also find catastrophic failure rates and biases that are consistently lower than for LSST. The added constraint on dark energy parameters for WL + CMB by Giga-z using the FoMSWG default model is equivalent to multiplying the LSST Fisher matrix by a factor of α = 1.27 (wp ), 1.53 (wa ), or 1.98 (Δγ). This is equivalent to multiplying both the LSST coverage area and the training sets by α and reducing all systematics by a factor of 1/\\sqrt{\\alpha }, advantages that are robust to even more extreme models of intrinsic alignment.

  7. Results and insights from the NCSU Insect Museum GigaPan project

    PubMed Central

    Bertone, Matthew A.; Blinn, Robert L.; Dew1, Tanner M. StanfieldKelly J.; Seltmann, Katja C.; Deans, Andrew R.

    2012-01-01

    Abstract Pinned insect specimens stored in museum collections are a fragile and valuable resource for entomological research. As such, they are usually kept away from viewing by the public and hard to access by experts. Here we present a method for mass imaging insect specimens, using GigaPan technology to achieve highly explorable, many-megapixel panoramas of insect museum drawers. We discuss the advantages and limitations of the system, and describe future avenues of collections research using this technology. PMID:22859883

  8. The density and spatial arrangement of the invasive oyster Crassostrea gigas determines its impact on settlement of native oyster larvae

    PubMed Central

    Wilkie, Emma M; Bishop, Melanie J; O'Connor, Wayne A

    2013-01-01

    Understanding how the density and spatial arrangement of invaders is critical to developing management strategies of pest species. The Pacific oyster, Crassostrea gigas, has been translocated around the world for aquaculture and in many instances has established wild populations. Relative to other species of bivalve, it displays rapid suspension feeding, which may cause mortality of pelagic invertebrate larvae. We compared the effect on settlement of Sydney rock oyster, Saccostrea glomerata, larvae of manipulating the spatial arrangement and density of native S. glomerata, and non-native C. gigas. We hypothesized that while manipulations of dead oysters would reveal the same positive relationship between attachment surface area and S. glomerata settlement between the two species, manipulations of live oysters would reveal differing density-dependent effects between the native and non-native oyster. In the field, whether oysters were live or dead, more larvae settled on C. gigas than S. glomerata when substrate was arranged in monospecific clumps. When, however, the two species were interspersed, there were no differences in larval settlement between them. By contrast, in aquaria simulating a higher effective oyster density, more larvae settled on live S. glomerata than C. gigas. When C. gigas was prevented from suspension feeding, settlement of larvae on C. gigas was enhanced. By contrast, settlement was similar between the two species when dead. While the presently low densities of the invasive oyster C. gigas may enhance S. glomerata larval settlement in east Australian estuaries, future increases in densities could produce negative impacts on native oyster settlement. Synthesis and applications: Our study has shown that both the spatial arrangement and density of invaders can influence their impact. Hence, management strategies aimed at preventing invasive populations reaching damaging sizes should not only consider the threshold density at which impacts exceed

  9. Functional analysis of Pacific oyster (Crassostrea gigas) β-thymosin: Focus on antimicrobial activity.

    PubMed

    Nam, Bo-Hye; Seo, Jung-Kil; Lee, Min Jeong; Kim, Young-Ok; Kim, Dong-Gyun; An, Cheul Min; Park, Nam Gyu

    2015-07-01

    An antimicrobial peptide, ∼5 kDa in size, was isolated and purified in its active form from the mantle of the Pacific oyster Crassostrea gigas by C18 reversed-phase high-performance liquid chromatography. Matrix-assisted laser desorption ionisation time-of-flight analysis revealed 4656.4 Da of the purified and unreduced peptide. A comparison of the N-terminal amino acid sequence of oyster antimicrobial peptide with deduced amino acid sequences in our local expressed sequence tag (EST) database of C. gigas (unpublished data) revealed that the oyster antimicrobial peptide sequence entirely matched the deduced amino acid sequence of an EST clone (HM-8_A04), which was highly homologous with the β-thymosin of other species. The cDNA possessed a 126-bp open reading frame that encoded a protein of 41 amino acids. To confirm the antimicrobial activity of C. gigas β-thymosin, we overexpressed a recombinant β-thymosin (rcgTβ) using a pET22 expression plasmid in an Escherichia coli system. The antimicrobial activity of rcgTβ was evaluated and demonstrated using a bacterial growth inhibition test in both liquid and solid cultures.

  10. Changes in protein expression of pacific oyster Crassostrea gigas exposed in situ to urban sewage.

    PubMed

    Flores-Nunes, Fabrício; Gomes, Tânia; Company, Rui; Moraes, Roberta R M; Sasaki, Silvio T; Taniguchi, Satie; Bicego, Márcia C; Melo, Cláudio M R; Bainy, Afonso C D; Bebianno, Maria J

    2015-11-01

    The composition and concentration of substances in urban effluents are complex and difficult to measure. These contaminants elicit biological responses in the exposed organisms. Proteomic analysis is a powerful tool in environmental toxicology by evidencing alterations in protein expression due to exposure to contaminants and by providing a useful framework for the development of new potential biomarkers. The aim of this study was to determine changes in protein expression signatures (PES) in the digestive gland of oysters Crassostrea gigas transplanted to two farming areas (LIS and RIB) and to one area contaminated by sanitary sewage (BUC) after 14 days of exposure. This species is one of the most cultivated molluscs in the world. The identified proteins are related to the cytoskeleton (CKAP5 and ACT2), ubiquitination pathway conjugation (UBE3C), G protein-coupled receptor and signal transduction (SVEP1), and cell cycle/division (CCNB3). CKAP5 showed higher expression in oysters kept at BUC in comparison with those kept at the farming areas, while ACT2, UBE3C, SVEP1, and CCNB3 were suppressed. The results suggest that these changes might lead to DNA damage, apoptosis, and interference with the immune system in oyster C. gigas exposed to sewage and give initial information on PES of C. gigas exposed to sanitary sewage, which can subsequently be useful in the development of more sensitive tools for biomonitoring coastal areas, particularly those devoted mainly to oyster farming activities.

  11. Endonuclease banding reveals that atrazine-induced aneuploidy resembles spontaneous chromosome loss in Crassostrea gigas.

    PubMed

    Bouilly, Karine; Leitão, Alexandra; Chaves, Raquel; Guedes-Pinto, Henrique; Boudry, Pierre; Lapègue, Sylvie

    2005-02-01

    Aneuploidy has previously been observed in the Pacific oyster, Crassostrea gigas, and shown to be negatively correlated with growth. Moreover, a significant impact of atrazine exposure has been described in C. gigas, and persistence of that effect has been observed between generations. Evidence of differential chromosome loss has been demonstrated in aneuploid karyotypes of C. gigas using the G-banding technique. Pairs 1, 5, 9, and 10 are characterized by the loss of 1 chromosome. As restriction enzyme (RE) digestion chromosome banding allows a better identification of chromosome pairs, we used this technique to identify which chromosomes are affected when aneuploidy is increased by exposure to atrazine. The progeny of oysters contaminated by atrazine were analysed using the restriction enzyme HaeIII. The study of 26 RE-banded aneuploid karyotypes showed that the same chromosome pairs (1, 5, 9, and 10) were affected by the loss of 1 chromosome (61%, 15%, 42%, and 42%, respectively). Further investigation is required to enable a better understanding of aneuploidy in oysters, especially with respect to why some chromosomes are more easily lost than others, and why cells tolerate the loss of these chromosomes.

  12. The Kinome of Pacific Oyster Crassostrea gigas, Its Expression during Development and in Response to Environmental Factors

    PubMed Central

    Epelboin, Yanouk; Quintric, Laure; Guévélou, Eric; Boudry, Pierre; Pichereau, Vianney; Corporeau, Charlotte

    2016-01-01

    Oysters play an important role in estuarine and coastal marine habitats, where the majority of humans live. In these ecosystems, environmental degradation is substantial, and oysters must cope with highly dynamic and stressful environmental constraints during their lives in the intertidal zone. The availability of the genome sequence of the Pacific oyster Crassostrea gigas represents a unique opportunity for a comprehensive assessment of the signal transduction pathways that the species has developed to deal with this unique habitat. We performed an in silico analysis to identify, annotate and classify protein kinases in C. gigas, according to their kinase domain taxonomy classification, and compared with kinome already described in other animal species. The C. gigas kinome consists of 371 protein kinases, making it closely related to the sea urchin kinome, which has 353 protein kinases. The absence of gene redundancy in some groups of the C. gigas kinome may simplify functional studies of protein kinases. Through data mining of transcriptomes in C. gigas, we identified part of the kinome which may be central during development and may play a role in response to various environmental factors. Overall, this work contributes to a better understanding of key sensing pathways that may be central for adaptation to a highly dynamic marine environment. PMID:27231950

  13. Repertoire and evolution of TNF superfamily in Crassostrea gigas: implications for expansion and diversification of this superfamily in Mollusca.

    PubMed

    Gao, Dahai; Qiu, Limei; Gao, Qiang; Hou, Zhanhui; Wang, Lingling; Song, Linsheng

    2015-08-01

    Tumor necrosis factor superfamily (TNFSF) members represent a group of cytokines participating in diverse immunological, pathological and developmental pathways. However, compared with deuterostomia and cnidaia, the composition and evolution of TNF homologous in protostomia are still not well understood. In the present study, a total of 81 TNF superfamily (TNFSF) genes from 15 mollusk species, including 23 TNFSF genes from Crassostrea gigas, were surveyed by genome-wide bioinformatics analysis. The phylogenetic analysis showed that 14 out of 23 C. gigas TNFSF genes in five clades exhibited orthologous relationships with Pinctada fucata TNFSF genes. Moreover, there were 15 C. gigas TNFSF genes located in oyster-specific clusters, which were contributed by small-scaled tandem and/or segmental duplication events in oyster. By comparing the sequences of duplicated TNFSF pairs, exon loss and variant in exon/intron length were revealed as the major modes of divergence in gene structure. Most of the duplicated C. gigas TNFSF pairs were evolved under purifying selection with consistent tissue expression patterns, implying functional constraint shaped diversification. This study demonstrated the expansion and early divergence of TNF superfamily in C. gigas, which provides potential insight into revealing the evolution and function of this superfamily in mollusk.

  14. Quantitative analysis of marker compounds in Angelica gigas, Angelica sinensis, and Angelica acutiloba by HPLC/DAD.

    PubMed

    Jeong, Su Yang; Kim, Hye Mi; Lee, Kyu Ha; Kim, Kyu Yeob; Huang, Dae Sun; Kim, Jong Hwan; Seong, Rack Seon

    2015-01-01

    Although Danggui is the root of Angelica gigas NAKAI in the Korean Pharmacopoeia, it is determined that Danggui is also the root of Angelica sinensis (OLIV.) DIELS in China and Hong Kong, as well as the root of Angelica acutiloba KITAGAWA in Japan. Accordingly, we tried to develop an identification method using the main compounds in A. gigas, A. sinensis, and A. acutiloba through HPLC/diode-array detector (DAD). This method was fully validated for linearity, accuracy, precision, recovery, and robustness. Multivariate analysis was also implemented after pattern analysis and monitoring. As a result, each compound pattern of A. gigas, A. sinensis, and A. acutiloba was identified, making it possible to distinguish them from each other.

  15. RAPID-COMMUNICATION Genetic diversity and differentiation in natural populations of Arapaima gigas from lower Amazon revealed by microsatellites.

    PubMed

    Fazzi-Gomes, P F; Melo, N; Palheta, G; Guerreiro, S; Amador, M; Ribeiro-Dos-Santos, A K; Santos, S; Hamoy, I

    2017-02-08

    Genetic variability is one of the important criteria for species conservation decisions. This study aimed to analyze the genetic diversity and the population differentiation of two natural populations of Arapaima gigas, a species with a long history of being commercially exploited. We collected 87 samples of A. gigas from Grande Curuai Lake and Paru Lake, located in the Lower Amazon region of Amazônia, Brazil, and genotyped these samples using a multiplex panel of microsatellite markers. Our results showed that the populations of A. gigas analyzed had high levels of genetic variability, which were similar to those described in previous studies. These two populations had a significant population differentiation supported by the estimates of FST and RST (0.06), by Bayesian analysis (K = 2), and by population assignment tests, which revealed a moderate genetic distance.

  16. Interactive Effects of Chronic Cigarette Smoking and Age on Brain Volumes in Controls and Alcohol Dependent Individuals in Early Abstinence

    PubMed Central

    Durazzo, Timothy C.; Mon, Anderson; Pennington, David; Abé, Christoph; Gazdzinski, Stefan; Meyerhoff, Dieter J.

    2012-01-01

    Chronic alcohol use disorders (AUD) have been shown to interact with normal age-related volume loss to exacerbate brain atrophy with increasing age. However, chronic cigarette smoking, a highly comorbid condition in AUD, and its influence on age-related brain atrophy has not been evaluated. We performed 1.5T quantitative MRI in non-smoking controls (nsCON; n=54), smoking light drinking controls (sCON, n=34), and 1-week-abstinent, treatment-seeking non-smoking alcohol dependent individuals (nsALC, n=35) and smoking ALC (sALC, n=43), to evaluate the independent and interactive effects of alcohol dependence and chronic smoking on regional cortical and subcortical brain volumes, emphasizing the brain reward/executive oversight system (BREOS),. nsCON and sALC showed greater age-related volume losses than nsALC in the dorsal prefrontal cortex (DPFC), total cortical BREOS, superior parietal lobule and putamen. nsALC and sALC demonstrated smaller volumes than nsCON in most cortical ROIs. sCON had smaller volumes than nsCON in the DPFC, insula, inferior parietal lobule, temporal pole/parahippocampal region and all global cortical measures. nsALC and sALC had smaller volumes than sCON in the DPFC, superior temporal gyrus, inferior and superior parietal lobules, precuneus and all global cortical measures. Volume differences between nsALC and sALC were observed only in the putamen. Alcohol consumption measures were not related to volumes in any ROI for ALC; smoking severity measures were related to corpus callosum volume in sCON and sALC. The findings indicate that consideration of smoking status is necessary for a better understanding of the factors contributing to regional brain atrophy in AUD. PMID:22943795

  17. ENSO variability during MIS 11 (424-374 ka) from Tridacna gigas at Huon Peninsula, Papua New Guinea

    NASA Astrophysics Data System (ADS)

    Ayling, Bridget F.; Chappell, John; Gagan, Michael K.; McCulloch, Malcolm T.

    2015-12-01

    Marine Isotope Stage 11 (MIS 11) from ∼424,000 to 374,000 yrs ago included one of the longest and warmest interglacials of the last 800,000 yrs, and is a potential analogue for the Holocene due to the similarity of Earth's orbital configuration at this time. The question of how the El Niño-Southern Oscillation (ENSO) responds to warmer background climates remains unanswered and is critical to understand how the ENSO system will evolve under the influence of anthropogenic warming. In this study, we present a 35 yr-long, high-resolution record of MIS 11 climate variability in the Western Pacific Warm Pool (WPWP) based on coupled measurements of skeletal Mg/Ca and δ18O in giant Tridacna gigas clams from Huon Peninsula, Papua New Guinea. The δ18O of modern T. gigas from Huon Peninsula faithfully records sea surface temperature, salinity/rainfall and regional ENSO variability. The geochemical integrity of the MIS 11 T. gigas for recording paleo-ENSO events was established through trace element screening, detailed petrography and SEM analysis. The fossil T. gigas δ18O record indicates that ENSO was operating during a 35-yr window in MIS 11, but with fewer events of shorter duration compared to those experienced during the last 100 yrs. The suppressed ENSO variability in the MIS 11 T. gigas record corresponds with a reduction in the amplitude of the average annual cycle in δ18O values. Distinctive changes in local insolation seasonality, and T. gigas δ18O, brought about by changes in Earth's orbit, provide an additional geochronological constraint on the timing of reef growth at Huon Peninsula to around 402 ka during the MIS 11.3 sub-stage (∼424-395 ka).

  18. Sex Ratio and Sex Reversal in Two-year-old Class of Oyster, Crassostrea gigas (Bivalvia: Ostreidae).

    PubMed

    Park, Jung Jun; Kim, Hyejin; Kang, Seung Wan; An, Cheul Min; Lee, Sung-Ho; Gye, Myung Chan; Lee, Jung Sick

    2012-12-01

    The sex ratio (F:M) in the same population of oyster, Crassostrea gigas at the commencement of the study (2007) was 1:1.0, but changed to 1:2.8 by the end of the study (2008). The sex reversal rate in two-year-old oysters was 40.2%. Specifically, female to male sex reversal rate was 66.1%, which is higher than the male to female sex reversal rate of 21.1%. The sex reversal pattern of C. gigas appears to go from male⇒female⇒male, and as such is determined to be rhythmical hermaphroditism.

  19. Exploitable Lipids and Fatty Acids in the Invasive Oyster Crassostrea gigas on the French Atlantic Coast

    PubMed Central

    Dagorn, Flore; Couzinet-Mossion, Aurélie; Kendel, Melha; Beninger, Peter G.; Rabesaotra, Vony; Barnathan, Gilles; Wielgosz-Collin, Gaëtane

    2016-01-01

    Economic exploitation is one means to offset the cost of controlling invasive species, such as the introduced Pacific oyster (Crassostrea gigas Thunberg) on the French Atlantic coast. Total lipid and phospholipid (PL) fatty acids (FAs) and sterols were examined in an invasive population of C. gigas in Bourgneuf Bay, France, over four successive seasons, with a view to identify possible sources of exploitable substances. The total lipid level (% dry weight) varied from 7.1% (winter) to 8.6% (spring). Of this, PLs accounted for 28.1% (spring) to 50.4% (winter). Phosphatidylcholine was the dominant PL throughout the year (up to 74% of total PLs in winter). Plasmalogens were identified throughout the year as a series of eleven dimethylacetals (DMAs) with chain lengths between C16 and C20 (up to 14.5% of PL FAs + DMAs in winter). Thirty-seven FAs were identified in the PL FAs. Eicosapentaenoic acid (20:5n-3 EPA/7.53% to 14.5%) and docosahexaenoic acid (22:6n-3 DHA/5.51% to 9.5%) were the dominant polyunsaturated FAs in all seasons. Two non-methylene-interrupted dienoic (NMID) FAs were identified in all seasons: 7,13-docosadienoic and 7,15-docosadienoic acids, the latter being present at relatively high levels (up to 9.6% in winter). Twenty free sterols were identified, including cholesterol at 29.9% of the sterol mixture and about 33% of phytosterols. C. gigas tissues thus contained exploitable lipids for health benefits or as a potential source of high-quality commercial lecithin. PMID:27231919

  20. Comprehensive model of Jumbo squid Dosidicus gigas trophic ecology in the Northern Humboldt current system.

    PubMed

    Alegre, Ana; Ménard, Frédéric; Tafur, Ricardo; Espinoza, Pepe; Argüelles, Juan; Maehara, Víctor; Flores, Oswaldo; Simier, Monique; Bertrand, Arnaud

    2014-01-01

    The jumbo squid Dosidicus gigas plays an important role in marine food webs both as predator and prey. We investigated the ontogenetic and spatiotemporal variability of the diet composition of jumbo squid in the northern Humboldt Current system. For that purpose we applied several statistical methods to an extensive dataset of 3,618 jumbo squid non empty stomachs collected off Peru from 2004 to 2011. A total of 55 prey taxa was identified that we aggregated into eleven groups. Our results evidenced a large variability in prey composition as already observed in other systems. However, our data do not support the hypothesis that jumbo squids select the most abundant or energetic taxon in a prey assemblage, neglecting the other available prey. Indeed, multinomial model predictions showed that stomach fullness increased with the number of prey taxa, while most stomachs with low contents contained one or two prey taxa only. Our results therefore question the common hypothesis that predators seek locally dense aggregations of monospecific prey. In addition D. gigas consumes very few anchovy Engraulis ringens in Peru, whereas a tremendous biomass of anchovy is potentially available. It seems that D. gigas cannot reach the oxygen unsaturated waters very close to the coast, where the bulk of anchovy occurs. Indeed, even if jumbo squid can forage in hypoxic deep waters during the day, surface normoxic waters are then required to recover its maintenance respiration (or energy?). Oxygen concentration could thus limit the co-occurrence of both species and then preclude predator-prey interactions. Finally we propose a conceptual model illustrating the opportunistic foraging behaviour of jumbo squid impacted by ontogenetic migration and potentially constrained by oxygen saturation in surface waters.

  1. Comprehensive Model of Jumbo Squid Dosidicus gigas Trophic Ecology in the Northern Humboldt Current System

    PubMed Central

    Alegre, Ana; Ménard, Frédéric; Tafur, Ricardo; Espinoza, Pepe; Argüelles, Juan; Maehara, Víctor; Flores, Oswaldo; Simier, Monique; Bertrand, Arnaud

    2014-01-01

    The jumbo squid Dosidicus gigas plays an important role in marine food webs both as predator and prey. We investigated the ontogenetic and spatiotemporal variability of the diet composition of jumbo squid in the northern Humboldt Current system. For that purpose we applied several statistical methods to an extensive dataset of 3,618 jumbo squid non empty stomachs collected off Peru from 2004 to 2011. A total of 55 prey taxa was identified that we aggregated into eleven groups. Our results evidenced a large variability in prey composition as already observed in other systems. However, our data do not support the hypothesis that jumbo squids select the most abundant or energetic taxon in a prey assemblage, neglecting the other available prey. Indeed, multinomial model predictions showed that stomach fullness increased with the number of prey taxa, while most stomachs with low contents contained one or two prey taxa only. Our results therefore question the common hypothesis that predators seek locally dense aggregations of monospecific prey. In addition D. gigas consumes very few anchovy Engraulis ringens in Peru, whereas a tremendous biomass of anchovy is potentially available. It seems that D. gigas cannot reach the oxygen unsaturated waters very close to the coast, where the bulk of anchovy occurs. Indeed, even if jumbo squid can forage in hypoxic deep waters during the day, surface normoxic waters are then required to recover its maintenance respiration (or energy?). Oxygen concentration could thus limit the co-occurrence of both species and then preclude predator-prey interactions. Finally we propose a conceptual model illustrating the opportunistic foraging behaviour of jumbo squid impacted by ontogenetic migration and potentially constrained by oxygen saturation in surface waters. PMID:24465788

  2. Transcriptomic Responses to Salinity Stress in the Pacific Oyster Crassostrea gigas

    PubMed Central

    Zhao, Xuelin; Yu, Hong; Kong, Lingfeng; Li, Qi

    2012-01-01

    Background Low salinity is one of the main factors limiting the distribution and survival of marine species. As a euryhaline species, the Pacific oyster Crassostrea gigas is considered to be tolerant to relative low salinity. The genes that regulate C. gigas responses to osmotic stress were monitored using the next-generation sequencing of whole transcriptome with samples taken from gills. By RNAseq technology, transcript catalogs of up- and down-regulated genes were generated from the oysters exposed to low and optimal salinity seawater. Methodology/Principal Findings Through Illumina sequencing, we reported 1665 up-regulated transcripts and 1815 down-regulated transcripts. A total of 45771 protein-coding contigs were identified from two groups based on sequence similarities with known proteins. As determined by GO annotation and KEGG pathway mapping, functional annotation of the genes recovered diverse biological functions and processes. The genes that changed expression significantly were highly represented in cellular process and regulation of biological process, intracellular and cell, binding and protein binding according to GO annotation. The results highlighted genes related to osmoregulation, signaling and interactions of osmotic stress response, anti-apoptotic reactions as well as immune response, cell adhesion and communication, cytoskeleton and cell cycle. Conclusions/Significance Through more than 1.5 million sequence reads and the expression data of the two libraries, the study provided some useful insights into signal transduction pathways in oysters and offered a number of candidate genes as potential markers of tolerance to hypoosmotic stress for oysters. In addition, the characterization of C. gigas transcriptome will not only provide a better understanding of the molecular mechanisms about the response to osmotic stress of the oysters, but also facilitate research into biological processes to find underlying physiological adaptations to

  3. Molecular and functional characterization of hemocyanin of the giant African millipede, Archispirostreptus gigas.

    PubMed

    Damsgaard, Christian; Fago, Angela; Hagner-Holler, Silke; Malte, Hans; Burmester, Thorsten; Weber, Roy E

    2013-05-01

    In contrast to other terrestrial arthropods, where gaseous O2 that fuels aerobic metabolism diffuses to the tissues in tracheal tubes, and most other metazoans, where O2 is transported to tissues by circulating respiratory proteins, the myriapods (millipedes and centipedes) strikingly have tracheal systems as well as circulating hemocyanin (Hc). In order to elucidate the evolutionary origin and biological significance of millipede Hc, we report the molecular structure (subunit composition and amino acid sequence) of multimeric (36-mer) Hc from the forest floor-dwelling giant African millipede Archispirostreptus gigas and its allosteric oxygen-binding properties under various physico-chemical conditions. Archispirostreptus gigas Hc consists of only a single subunit type with differential glycosylation. Phylogenic analysis revealed that millipede Hc is a sister group to centipede HcA, which supports an early divergence of distinct Hc subunits in myriapods and an ancient origin of multimeric Hcs. Archispirostreptus gigas Hc binds O2 with a high affinity and shows a strong Bohr effect. O2 binding is, moreover, modulated by Ca(2+) ions, which increase the O2 affinity of the Hc in the tense (T; deoxygenated) as well as the relaxed (R; oxygenated) states, and by (l)-lactate, which modulates Hc-O2 affinity by changing the allosteric equilibrium constant, L. Cooperativity in O2 binding at half O2 saturation (n50) is pH dependent and maximal at ~pH 7.4, and the number of interacting O2-binding sites (q) is markedly increased by binding Ca(2+). The data are discussed in the light of the mutually supplementary roles of Hc and the tracheal system for tissue O2 supply.

  4. Heavy-metal contamination of the Pacific oysters (Crassostrea gigas) cultured in Deep Bay, Hong Kong

    SciTech Connect

    Wong, M.H.; Choy, C.K.; Lau, W.M.; Cheung, Y.H.

    1981-08-01

    Samples of Pacific oysters, Crassostrea gigas, cultured in Deep Bay, Hong Kong, were collected for analysis of various heavy-metal contents: iron, copper, lead, cadmium, manganese, chromium, and zinc. In general, the gill had the highest metal contents, followed by the mantle, the viscera, with the smallest amount being observed in the adductor muscle. All metal contents obtained in the present study were within the range reported for the same species in areas where heavy-metal pollution is already recognized as a problem. A long-term monitoring program of measuring the contents of various metals in seawater, sediment, and oysters is therefore essential.

  5. Invasive range expansion by the Humboldt squid, Dosidicus gigas, in the eastern North Pacific.

    PubMed

    Zeidberg, Louis D; Robison, Bruce H

    2007-07-31

    A unique 16-year time series of deep video surveys in Monterey Bay reveals that the Humboldt squid, Dosidicus gigas, has substantially expanded its perennial geographic range in the eastern North Pacific by invading the waters off central California. This sustained range expansion coincides with changes in climate-linked oceanographic conditions and a reduction in competing top predators. It is also coincident with a decline in the abundance of Pacific hake, the most important commercial groundfish species off western North America. Recognizing the interactive effects of multiple changes in the environment is an issue of growing concern in ocean conservation and sustainability research.

  6. [Rearing crassostrea gigas (Bivalvia:Ostreidae) in a semi-rigid net].

    PubMed

    Acosta Ruíz, M J; Gutiérrez Wing, M T

    1996-08-01

    A culture system, consisting of a semi-rigid net, with an ABS frame filled with styrofoam was used for the culture of the Pacific oyster Crassostrea gigas, from 3.0 mm length seed. The culture system was tested in three locations, two inside San Quintín Bay and one in San Martín Island. The mean monthly growth was 8.69 mm and 8.96 mm in the Bay and 7.33 mm in San Martín Island. These growth rates show that this species can attain commercial sizes in 6 months, using the culture system tested.

  7. Protective Effect of Decursin Extracted from Angelica gigas in Male Infertility via Nrf2/HO-1 Signaling Pathway.

    PubMed

    Bae, Woong Jin; Ha, U Syn; Choi, Jin Bong; Kim, Kang Sup; Kim, Su Jin; Cho, Hyuk Jin; Hong, Sung Hoo; Lee, Ji Youl; Wang, Zhiping; Hwang, Sung Yeoun; Kim, Sae Woong

    2016-01-01

    Higher testicular temperature results in altered spermatogenesis due to heat-related oxidative stress. We examined the effects of decursin extracted from Angelica gigas Nakai on antioxidant activity in vitro and in a cryptorchidism-induced infertility rat model. TM3 Leydig cell viability was measured based on oxidative stress according to treatment. Either distilled water or AG 400 mg/kg of A. gigas extract was administered orally for 4 weeks after unilateral cryptorchidism was induced. After 1, 2, and 4 weeks, six rats from the control group and six rats from treatment group were sacrificed. Testicular weight, semen quality, antioxidant activities, nuclear factor erythroid 2-related factor 2 (Nrf2) protein, and mRNA expression of Nrf2-regulated genes were analyzed. Treatment with A. gigas extract (1) protected TM3 cells against oxidative stress in a dose-dependent manner, (2) improved the mean weight of the cryptorchid testis, (3) maintained sperm counts, motility, and spermatogenic cell density, (4) decreased levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) and increased levels of superoxide dismutase (SOD), (5) significantly increased Nrf2 and heme oxygenase-1 (HO-1), and (6) significantly decreased apoptosis. This study suggests that decursin extracted from A. gigas is a supplemental agent that can reduce oxidative stress by Nrf2-mediated upregulation of HO-1 in rat experimentally induced unilateral cryptorchidism and may improve cryptorchidism-induced infertility.

  8. Changes in molecular genetic variation at ALFP loci associated with naturalization and domestication of the Pacific oyster (Crassostrea gigas)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pacific oyster (Crassostrea gigas) is an important commercial species in the US Pacific Northwest with a history of propagation first using wild-caught seed imported directly from the Miyagi region of northern Japan (1920s – 1970s) followed by an extended period of seed collection from a few sel...

  9. Genomic analysis of the Pacific oyster (Crassostrea gigas) reveals possible conservation of vertebrate sex determination in a mollusc.

    PubMed

    Zhang, Na; Xu, Fei; Guo, Ximing

    2014-09-11

    Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors.

  10. Genomic Analysis of the Pacific Oyster (Crassostrea gigas) Reveals Possible Conservation of Vertebrate Sex Determination in a Mollusc

    PubMed Central

    Zhang, Na; Xu, Fei; Guo, Ximing

    2014-01-01

    Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors. PMID:25213692

  11. Use of laboratory assays to predict subsequent growth and survival of Pacific oyster (Crassostrea gigas) families planted in coastal waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selective breeding programs for improving Pacific oyster (Crassostrea gigas) stocks are expensive, labor-intensive, and rely on lengthy field trials that are subject to stochastic outbreaks of Summer Mortality Syndrome. Laboratory assays that identify and eliminate poor-performing families prior to...

  12. Crystal Structure of Dimeric Flavodoxin from Desulfovibrio gigas Suggests a Potential Binding Region for the Electron-Transferring Partner

    PubMed Central

    Hsieh, Yin-Cheng; Chia, Tze Shyang; Fun, Hoong-Kun; Chen, Chun-Jung

    2013-01-01

    Flavodoxins, which exist widely in microorganisms, have been found in various pathways with multiple physiological functions. The flavodoxin (Fld) containing the cofactor flavin mononucleotide (FMN) from sulfur-reducing bacteria Desulfovibrio gigas (D. gigas) is a short-chain enzyme that comprises 146 residues with a molecular mass of 15 kDa and plays important roles in the electron-transfer chain. To investigate its structure, we purified this Fld directly from anaerobically grown D. gigas cells. The crystal structure of Fld, determined at resolution 1.3 Å, is a dimer with two FMN packing in an orientation head to head at a distance of 17 Å, which generates a long and connected negatively charged region. Two loops, Thr59–Asp63 and Asp95–Tyr100, are located in the negatively charged region and between two FMN, and are structurally dynamic. An analysis of each monomer shows that the structure of Fld is in a semiquinone state; the positions of FMN and the surrounding residues in the active site deviate. The crystal structure of Fld from D. gigas agrees with a dimeric form in the solution state. The dimerization area, dynamic characteristics and structure variations between monomers enable us to identify a possible binding area for its functional partners. PMID:23322018

  13. Growth and survival of juvenile queen conch, Strombus gigas fed artificial diets containing varying levels of digestible protein and energy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquaculture methods for queen conch, Strombus gigas, have been established for several decades. However, there is a need to improve husbandry techniques for the growout of juveniles. The purpose of this study was to determine growth and survival of juvenile queen conch fed artificial diets with incr...

  14. Exposure to the Paralytic Shellfish Toxin Producer Alexandrium catenella Increases the Susceptibility of the Oyster Crassostrea gigas to Pathogenic Vibrios

    PubMed Central

    Abi-Khalil, Celina; Lopez-Joven, Carmen; Abadie, Eric; Savar, Veronique; Amzil, Zouher; Laabir, Mohamed; Rolland, Jean-Luc

    2016-01-01

    The multifactorial etiology of massive Crassostrea gigas summer mortalities results from complex interactions between oysters, opportunistic pathogens and environmental factors. In a field survey conducted in 2014 in the Mediterranean Thau Lagoon (France), we evidenced that the development of the toxic dinoflagellate Alexandrium catenella, which produces paralytic shellfish toxins (PSTs), was concomitant with the accumulation of PSTs in oyster flesh and the occurrence of C. gigas mortalities. In order to investigate the possible role of toxic algae in this complex disease, we experimentally infected C. gigas oyster juveniles with Vibrio tasmaniensis strain LGP32, a strain associated with oyster summer mortalities, after oysters were exposed to Alexandrium catenella. Exposure of oysters to A. catenella significantly increased the susceptibility of oysters to V. tasmaniensis LGP32. On the contrary, exposure to the non-toxic dinoflagellate Alexandrium tamarense or to the haptophyte Tisochrysis lutea used as a foraging alga did not increase susceptibility to V. tasmaniensis LGP32. This study shows for the first time that A. catenella increases the susceptibility of Crassostrea gigas to pathogenic vibrios. Therefore, in addition to complex environmental factors explaining the mass mortalities of bivalve mollusks, feeding on neurotoxic dinoflagellates should now be considered as an environmental factor that potentially increases the severity of oyster mortality events. PMID:26784228

  15. Anti-Inflammatory Effect of Angelica gigas via Heme Oxygenase (HO)-1 Expression.

    PubMed

    Cho, Joon Hyeong; Kwon, Jung Eun; Cho, Youngmi; Kim, Inhye; Kang, Se Chan

    2015-06-15

    Angelica gigas (AG) is effective against various medical conditions such as bacterial infection, inflammation, and cancer. It contains a number of coumarin compounds and the group of interest is the pyranocoumarin, which comprises decursin and decursinol angelate. This group has an effect on controlling inflammation, which is caused by excessive nitric oxide (NO) production. Heme oxygenases (HOs), particularly HO-1, play a role in regulating the production of NO. Thus, this study aimed to investigate the anti-inflammatory effects of AG by measuring HO-1 expression. Treatments with CH2Cl2 layer and Angelica gigas extract (AGE) showed the highest NO inhibition effects. Decursin, decursinol angelate, and nodakenin were isolated from the CH2Cl2 layer of AGE. Decursin also demonstrated the highest anti-oxidative effect among the coumarins. Although decursin had the best NO inhibition and anti-oxidative effects, the effects of AGE treatment far surpassed that of decursin. This is owing to the combination effect of the coumarins present within AGE, which is a solvent extract of AG. The expression of HO-1 is an effective indicator of the anti-inflammatory effects of AG. Based on the results of the coumarin compounds, HO-1 expression was found to be dose dependent and specific to decursin.

  16. DNA methylation is crucial for the early development in the Oyster C. gigas.

    PubMed

    Riviere, Guillaume; Wu, Guan-Chung; Fellous, Alexandre; Goux, Didier; Sourdaine, Pascal; Favrel, Pascal

    2013-12-01

    In vertebrates, epigenetic modifications influence gene transcription, and an appropriate DNA methylation is critical in development. Indeed, a precise temporal and spatial pattern of early gene expression is mandatory for a normal embryogenesis. However, such a regulation and its underlying mechanisms remain poorly understood in more distant organisms such as Lophotrochozoa. Thus, despite DNA in the oyster genome being methylated, the role of DNA methylation in development is unknown. To clarify this point, oyster genomic DNA was examined during early embryogenesis and found differentially methylated. Reverse transcriptase quantitative polymerase chain reaction indicated stage-specific levels of transcripts encoding DNA-methyltransferase (DNMT) and methyl-binding domain proteins. In addition, as highlighted by electronic microscopy and immunohistochemistry, the DNMT inhibitor 5-aza-cytidine induced alterations in the quantity and the localisation of methylated DNA and severe dose-dependent development alterations and was lethal after zygotic genome reinitiation. Furthermore, methyl-DNA-immunoprecipitation-quantitative polymerase chain reaction revealed that the transcription level of most of the homeobox gene orthologues examined, but not of the other early genes investigated, was inversely correlated with their specific DNA methylation. Altogether, our results demonstrate that DNA methylation influences gene expression in Crassostrea gigas and is critical for oyster development, possibly by specifically controlling the transcription level of homeobox orthologues. These findings provide evidence for the importance of epigenetic regulation of development in Lophotrochozoans and bring new insights into the early life of C. gigas, one of the most important aquaculture resources worldwide.

  17. Demography of the ecosystem engineer Crassostrea gigas, related to vertical reef accretion and reef persistence

    NASA Astrophysics Data System (ADS)

    Walles, Brenda; Mann, Roger; Ysebaert, Tom; Troost, Karin; Herman, Peter M. J.; Smaal, Aad C.

    2015-03-01

    Marine species characterized as structure building, autogenic ecosystem engineers are recognized worldwide as potential tools for coastal adaptation efforts in the face of sea level rise. Successful employment of ecosystem engineers in coastal protection largely depends on long-term persistence of their structure, which is in turn dependent on the population dynamics of the individual species. Oysters, such as the Pacific oyster (Crassostrea gigas), are recognized as ecosystem engineers with potential for use in coastal protection. Persistence of oyster reefs is strongly determined by recruitment and shell production (growth), processes facilitated by gregarious settlement on extant shell substrate. Although the Pacific oyster has been introduced world-wide, and has formed dense reefs in the receiving coastal waters, the population biology of live oysters and the quantitative mechanisms maintaining these reefs has rarely been studied, hence the aim of the present work. This study had two objectives: (1) to describe the demographics of extant C. gigas reefs, and (2) to estimate vertical reef accretion rates and carbonate production in these oyster reefs. Three long-living oyster reefs (>30 years old), which have not been exploited since their first occurrence, were examined in the Oosterschelde estuary in the Netherlands. A positive reef accretion rate (7.0-16.9 mm year-1 shell material) was observed, consistent with self-maintenance and persistent structure. We provide a framework to predict reef accretion and population persistence under varying recruitment, growth and mortality scenarios.

  18. Growth and reproductive investment of introduced Pacific oysters Crassostrea gigas in southern European waters

    NASA Astrophysics Data System (ADS)

    Cardoso, Joana F. M. F.; Peralta, Nelson R. E.; Machado, Jorge P.; van der Veer, Henk W.

    2013-02-01

    Growth and reproductive investment of cultured Pacific oysters Crassostrea gigas were studied in two south-western European estuaries: the Ría de Ribadeo in Spain and the Ria Formosa in Portugal. Developing gonads were found in individuals >23.5 mm shell length in the Ria Formosa and >27.5 mm shell length in the Ría de Ribadeo. Although the amount of gonadal mass in relation to total body mass was higher in the Ría de Ribadeo, oysters from this location did not spawn completely. In contrast, oysters from the Ria Formosa completely emptied their gonad during spawning. Reproduction and, consequently, the maximum potential for population expansion may be constrained in both areas: in the Ría de Ribadeo due to suboptimal spawning threshold temperatures and in the Ria Formosa due to higher metabolic costs caused by warmer winter temperatures. Nevertheless, in comparison to northern oyster populations, Portuguese and Spanish populations have higher reproductive output. If suitable environmental conditions are met, expansion of Portuguese and Spanish populations will most likely occur. In the Ria Formosa, where environmental conditions for growth and reproduction are favourable, wild oysters are already observed. In order to follow the dynamics of oyster populations and predict possible negative effects on the ecosystems, it is important to continue monitoring the physiological performance of C. gigas in these areas.

  19. Relationship between Marteilioides chungmuensis infection and reproduction in the Pacific oyster, Crassostrea gigas.

    PubMed

    Tun, Kay Lwin; Itoh, Naoki; Ueki, Noriyuki; Yoshinaga, Tomoyoshi; Ogawa, Kazuo

    2007-11-01

    Marteilioides chungmuensis, a protozoan paramyxean parasite, infects the oocytes of the Pacific oyster, Crassostrea gigas. The effects of infection on the reproductive cycle of C. gigas were investigated over two consecutive years at Okayama Prefecture, Japan. In male oysters, gonadal development began during February/March, maturity was achieved in June and spawning activity extended from July to September. In November and December, male oysters were not seen, probably because their gonads regressed to connective tissue and they transformed into undifferentiated oysters. By contrast, female oysters, in which parasite spore formation occurred, were still carrying oocytes until the following March and the spawning process of female oysters took 5 months longer than that of males in epizootic areas. The prevalence of M. chungmuensis infection increased from July to September, when most female oysters had their spawning period, and declined from October to the following April when oysters were at the spent stage. The prevalence of infection increased again in May of the following year and high prevalence was observed in the following July. When prevalence was compared between oysters of different age classes, higher prevalence was detected in older than in younger oysters. Histological examination showed that infected oysters produced oocytes continuously and spawned repeatedly from October to March, during which period healthy oysters were reproductively inactive. Parasites can infect the oocytes of infected oysters throughout the longer spawning period. These observations suggest that M. chungmuensis extends the reproductive period of infected oysters for its own reproductive benefit.

  20. Effect of chronic exposure to zinc in young spats of the Pacific oyster (Crassostrea gigas).

    PubMed

    Devos, Alexandre; Voiseux, Claire; Caplat, Christelle; Fievet, Bruno

    2012-12-01

    The marine coastal environment is exposed to a mixture of environmental pollutants of anthropogenic origin, resulting in chronic low concentrations of contaminants. As a consequence, most coastal marine species are exposed to low doses of such pollutants during their entire life. Many marine species live for years in their natural environment, whereas they do not under laboratory exposure conditions. Using early stages of development in laboratory work allows animals to be chronically exposed from an early age over a reasonable experiment period. In the present study, the authors investigated the effect of chronic exposure to zinc in spats of the Pacific oyster (Crassostrea gigas), from metamorphosis up to 10 weeks. The authors investigated integrated biological endpoints that would account for the apparent general health of the animals as well as molecular markers showing more subtle effects that could potentially go unnoticed at a biologically integrated level. The authors measured in parallel both growth and the transcriptional level of target stress genes. Growth was monitored by image analysis of large samples to avoid high variability and ensure statistical robustness. A dose-response relationship was derived from growth data, yielding a median effective concentration (EC50) of 7.55 µM. Stress genes selected on the basis of available RNA sequences in C. gigas included genes involved in chaperone proteins, oxidative stress, detoxification, and cell cycle regulation. Out of nine stress target genes, only metallothionein displayed overexpression in response to high levels of zinc.

  1. Distinct immune responses of juvenile and adult oysters (Crassostrea gigas) to viral and bacterial infections.

    PubMed

    Green, Timothy J; Vergnes, Agnes; Montagnani, Caroline; de Lorgeril, Julien

    2016-07-21

    Since 2008, massive mortality events of Pacific oysters (Crassostrea gigas) have been reported worldwide and these disease events are often associated with Ostreid herpesvirus type 1 (OsHV-1). Epidemiological field studies have also reported oyster age and other pathogens of the Vibrio genus are contributing factors to this syndrome. We undertook a controlled laboratory experiment to simultaneously investigate survival and immunological response of juvenile and adult C. gigas at different time-points post-infection with OsHV-1, Vibrio tasmaniensis LGP32 and V. aestuarianus. Our data corroborates epidemiological studies that juveniles are more susceptible to OsHV-1, whereas adults are more susceptible to Vibrio. We measured the expression of 102 immune-genes by high-throughput RT-qPCR, which revealed oysters have different transcriptional responses to OsHV-1 and Vibrio. The transcriptional response in the early stages of OsHV-1 infection involved genes related to apoptosis and the interferon-pathway. Transcriptional response to Vibrio infection involved antimicrobial peptides, heat shock proteins and galectins. Interestingly, oysters in the later stages of OsHV-1 infection had a transcriptional response that resembled an antibacterial response, which is suggestive of the oyster's microbiome causing secondary infections (dysbiosis-driven pathology). This study provides molecular evidence that oysters can mount distinct immune response to viral and bacterial pathogens and these responses differ depending on the age of the host.

  2. Dual analysis of host and pathogen transcriptomes in ostreid herpesvirus 1-positive Crassostrea gigas.

    PubMed

    Rosani, U; Varotto, L; Domeneghetti, S; Arcangeli, G; Pallavicini, A; Venier, P

    2015-11-01

    Ostreid herpesvirus type 1 (OsHV-1) has become a problematic infective agent for the Pacific oyster Crassostrea gigas. In particular, the OsHV-1 μVar subtype has been associated with severe mortality episodes in oyster spat and juvenile oysters in France and other regions of the world. Factors enhancing the infectivity of the virus and its interactions with susceptible and resistant bivalve hosts are still to be understood, and only few studies have explored the expression of oyster or viral genes during productive infections. In this work, we have performed a dual RNA sequencing analysis on an oyster sample with a high viral load. High sequence coverage allowed us to thoroughly explore the OsHV-1 transcriptome and identify the activated molecular pathways in C. gigas. The identification of several highly induced and defence-related oyster transcripts supports the crucial role played by the innate immune system against the virus and opportunistic microbes possibly contributing to subsequent spat mortality.

  3. Mass mortality in bivalves and the intricate case of the Pacific oyster, Crassostrea gigas.

    PubMed

    Barbosa Solomieu, Valérie; Renault, Tristan; Travers, Marie-Agnès

    2015-10-01

    Massive mortality outbreaks in cultured bivalves have been reported worldwide and they have been associated with infection by a range of viral and bacterial pathogens. Due to their economic and social impact, these episodes constitute a particularly sensitive issue in Pacific oyster (Crassostrea gigas) production. Since 2008, mortality outbreaks affecting C. gigas have increased in terms of intensity and geographic distribution. Epidemiologic surveys have lead to the incrimination of pathogens, specifically OsHV-1 and bacteria of the Vibrio genus, in particular Vibrio aestuarianus. Pathogen diversity may partially account for the variability in the outcome of infections. Host factors (age, reproductive status...) including their genetic background that has an impact on host susceptibility toward infection, also play a role herein. Finally, environmental factors have significant effects on the pathogens themselves, on the host and on the host-pathogen interaction. Further knowledge on pathogen diversity, classification, and spread, may contribute toward a better understanding of this issue and potential ways to mitigate the impact of these outbreaks.

  4. Anti-Inflammatory Effect of Angelica gigas via Heme Oxygenase (HO)-1 Expression

    PubMed Central

    Cho, Joon Hyeong; Kwon, Jung Eun; Cho, Youngmi; Kim, Inhye; Kang, Se Chan

    2015-01-01

    Angelica gigas (AG) is effective against various medical conditions such as bacterial infection, inflammation, and cancer. It contains a number of coumarin compounds and the group of interest is the pyranocoumarin, which comprises decursin and decursinol angelate. This group has an effect on controlling inflammation, which is caused by excessive nitric oxide (NO) production. Heme oxygenases (HOs), particularly HO-1, play a role in regulating the production of NO. Thus, this study aimed to investigate the anti-inflammatory effects of AG by measuring HO-1 expression. Treatments with CH2Cl2 layer and Angelica gigas extract (AGE) showed the highest NO inhibition effects. Decursin, decursinol angelate, and nodakenin were isolated from the CH2Cl2 layer of AGE. Decursin also demonstrated the highest anti-oxidative effect among the coumarins. Although decursin had the best NO inhibition and anti-oxidative effects, the effects of AGE treatment far surpassed that of decursin. This is owing to the combination effect of the coumarins present within AGE, which is a solvent extract of AG. The expression of HO-1 is an effective indicator of the anti-inflammatory effects of AG. Based on the results of the coumarin compounds, HO-1 expression was found to be dose dependent and specific to decursin. PMID:26083119

  5. Genetically Determined Variation in Developmental Physiology of Bivalve Larvae (Crassostrea gigas).

    PubMed

    Francis Pan, T-C; Applebaum, Scott L; Manahan, Donal T

    2015-01-01

    Understanding the complex interactions that regulate growth and form is a central question in developmental physiology. We used experimental crosses of pedigreed lines of the Pacific oyster, Crassostrea gigas, to investigate genetically determined variations in larval growth and nutrient transport. We show that (i) transport rates at 10 and 100 μM glycine scale differentially with size; (ii) size-specific maximum transport capacity (Jmax) is genetically determined; and (iii) Jmax serves as an early predictive index of subsequent growth rate. This relationship between genetically determined Jmax and growth suggests the potential use of transporter genes as biomarkers of growth potential. Analysis of the genome of C. gigas revealed 23 putative amino acid transporter genes. The complexity of gene families that underpin physiological traits has additional precedents in this species and others and warrants caution in the use of gene expression as a biomarker for physiological state. Direct in vivo measurements of physiological processes using species with defined genotypes are required to understand genetically determined variance of nutrient flux and other processes that regulate development and growth.

  6. The Rehbinder effect in iron during giga-cycle fatigue loading

    SciTech Connect

    Bannikov, M. V. Naimark, O. B.

    2015-10-27

    The influence of the adsorptive strength reduction effect (the Rehbinder effect) on the fatigue life of pure iron under the giga-cycle loading regime was investigated. Specimens were loaded by an ultrasonic testing machine with a frequency of 20 kHz in air and in contact with eutectic alloy of gallium with tin and indium. A significant (by several orders of magnitude) worsening of the life-time of iron in contact with a molten metal as compared with tests in air was established. The liquid metal penetrates into the material to a depth of 200 μm to the center of a fatigue crack. The mechanism of the fatigue crack initiation in the giga-cycle regime of loading in contact with a surfactant is differing: the crack is formed on the surface of the specimen rather than within it as is the case for air. Based on the electron and optical microscopy data for the fracture surface, it can be concluded that exactly the change in the crack initiation mechanism reduces the fatigue life of iron in contact with a liquid metal because the initiated crack propagates regardless of the surfactant.

  7. Genetics of the Steller's Sea Cow (Hydrodamalis gigas): A Study of Ancient Bone Material

    NASA Astrophysics Data System (ADS)

    Crerar, Lorelei D.

    Georg Wilhelm Steller was born 100 years before Darwin in 1709 and he was part of a vast exploration fifty years before Lewis and Clark explored America. Steller was important to the study of marine mammals because he was the only naturalist to see and describe the great northern sea cow ( Hydrodamalis gigas). Knowledge of an extinct population can be used to aid the conservation of a current population. Extraction of DNA from this extinct animal was performed in order to determine the population structure of the Steller's sea cow. A test was also developed that can definitively state whether or not a random bone sample came from H. gigas. This test could be used by the Fish and Wildlife Service (FWS) and the National Oceanic and Atmospheric Administration (NOAA) to examine material distributed in the North Pacific to determine whether samples are legally traded extinct Steller's sea cow or illegally traded extant marine mammal species protected under the Marine Mammal Protection Act (MMPA).

  8. Reversible stress softening of collagen based networks from the jumbo squid mantle (Dosidicus gigas).

    PubMed

    Torres, F G; Troncoso, O P; Rivas, E R; Gomez, C G; Lopez, D

    2014-04-01

    Dosidicus gigas is the largest and one of the most abundant jumbo squids in the eastern Pacific Ocean. In this paper we have studied the muscle of the mantle of D. gigas (DGM). Morphological, thermal and rheological properties were assessed by means of atomic force microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential scanning calorimetry, thermogravimetry and oscillatory rheometry. This study allowed us to assess the morphological and rheological properties of a collagen based network occurring in nature. The results showed that the DGM network displays a nonlinear effect called reversible stress softening (RSS) that has been previously described for other types of biological structures such as naturally occurring cellulose networks and actin networks. We propose that the RSS could play a key role on the way jumbo squids withstand hydrostatic pressure. The results presented here confirm that this phenomenon occurs in a wider number of materials than previously thought, all of them exhibiting different size scales as well as physical conformation.

  9. Behavioral ecology of jumbo squid (Dosidicus gigas) in relation to oxygen minimum zones

    NASA Astrophysics Data System (ADS)

    Stewart, Julia S.; Field, John C.; Markaida, Unai; Gilly, William F.

    2013-10-01

    Habitat utilization, behavior and food habits of the jumbo or Humboldt squid, Dosidicus gigas, were compared between an area recently inhabited in the northern California Current System (CCS) and a historically established area of residence in the Gulf of California (GOC). Low dissolved oxygen concentrations at midwater depths define the oxygen minimum zone (OMZ), an important environmental feature in both areas. We analyzed vertical diving behavior and diet of D. gigas and hydrographic properties of the water column to ascertain the extent to which squid utilized the OMZ in the two areas. The upper boundary of the OMZ has been shoaling in recent decades in the CCS, and this phenomenon has been proposed to vertically compress the pelagic environment inhabited by aerobic predators. A shoaling OMZ will also bring mesopelagic communities into a depth range with more illumination during daytime, making these organisms more vulnerable to predation by visual predators (i.e. jumbo squid). Because the OMZ in the GOC is considerably shallower than in the CCS, our study provides insight into the behavioral plasticity of jumbo squid and how they may respond to a shoaling OMZ in the CCS. We propose that shoaling OMZs are likely to be favorable to jumbo squid and could be a key indirect factor behind the recent range expansion of this highly migratory predator.

  10. Specific detection of Pacific oyster (Crassostrea gigas) larvae in plankton samples using nested polymerase chain reaction.

    PubMed

    Patil, Jawahar G; Gunasekera, Rasanthi M; Deagle, Bruce E; Bax, Nicholas J

    2005-01-01

    Management of sustainable Pacific oyster fisheries would be assisted by an early, rapid, and accurate means of detecting their planktonic larvae. Reported here is an approach, based on polymerase chain reaction (PCR), for the detection of Pacific oyster larvae in plankton samples. Species-specific primers were designed by comparing partial mitochondrial cytochrome oxidase subunit I (COI) sequences from Crassostrea gigas, with other members of the family Ostreidae including those of Crassostrea angulata. Assay specificity was empirically validated through screening DNA samples obtained from several species of oysters. The assay was specific as only C. gigas samples returned PCR-positive results. A nested PCR approach could consistently detect 5 or more D-hinge-stage larvae spiked into a background of about 146 mg of plankton. The assay does not require prior sorting of larvae. We conclude that the assay could be used to screen environmental and ballast water samples, although further specificity testing against local bivalve species is recommended in new locations.

  11. Histological survey of Pacific oysters Crassostrea gigas (Thunberg) in Galicia (NW Spain).

    PubMed

    Iglesias, David; Rodríguez, Luis; Gómez, Luis; Azevedo, Carlos; Montes, Jaime

    2012-11-01

    In Galicia, there is an increasingly interest among representatives of the oyster industry in the development of Pacific oyster Crassostrea gigas culture. Nevertheless severe mortalities and emerging health problems in this species have been recently reported in European farming areas. A histological survey was performed from 2004 to 2009 to assess health status in both cultured and wild Galician oysters. Different symbiotic organisms and conditions were detected, including viral gametocytic hypertrophy (VGH) which is reported here for first time in Spanish coast. VGH, prokaryote-like colonies and ciliates were observed in oyster tissues without causing host damage. A haplosporidian infection, copepods inducing lesions and a cellular proliferative disorder were detected in some samples causing moderate host damage; their low prevalence suggests these parasites are not a threat for C. gigas in Galicia. None of the parasites detected is OIE (Office International des Epizooties: the World Organization for Animal Health) notifiable. Although the current study did not identify any pathogens or diseases of concern, it provides important prevalence baseline data for future health and epidemiological assessments needed to better understanding the existing and emerging health problems in this species.

  12. Occurrence of Apicomplexa-like structures in the digestive gland of Strombus gigas throughout the Caribbean.

    PubMed

    Aranda, Dalila Aldana; Frenkiel, Liliane; Brulé, Thierry; Montero, Jorge; Cárdenas, Erick Baqueiro

    2011-02-01

    The queen conch, Strombus gigas, is a marine resource of ecological and economical importance in the Caribbean region. Given its importance in this region, and the critical status of most populations, the reproductive biology of this species has been studied to support management decisions. It was from these studies that a generalized sporozoan infection was detected. This study describes the geographic distribution of a coccidian (Apicomplexa) parasite infecting the digestive gland of S. gigas throughout the Caribbean. The parasite was present in every location sampled. Based on histological analysis, the parasites from all locations are similar and appear to complete their life cycle within the digestive gland. The highest occurrence of the parasites was registered in samples from Puerto Rico (54 parasites per field) and Martinique (45 parasites per field). The lowest incidence was registered on the Mexican coast of Yucatan peninsula, at Alacranes and Chinchorro with 17 parasites per field. Data showed significant differences among sites (Kruskal Wallis H=106.957; p ≤ 0.05). The abundance of parasites found in the digestive ducts and in the faeces suggests the liberation of parasites to the environment. A gradual decrease in abundance was found from East to West of the Caribbean sea.

  13. Inhibition of Desulfovibrio gigas hydrogenase with copper salts and other metal ions.

    PubMed

    Fernandez, V M; Rua, M L; Reyes, P; Cammack, R; Hatchikian, E C

    1989-11-06

    The effect of several transition metals on the activity of Desulfovibrio gigas hydrogenase has been studied. Co(II) and Ni(II) at a concentration of 1 mM did not modify the activity of the enzyme; nor did they affect the pattern of activation/deactivation. Cu(II) inhibited the active hydrogenase, prepared by treatment with hydrogen, but had little effect on the 'unready' enzyme unless a reductant such as ascorbate was present, in which case inactivation took place either in air or under argon. Hg(II) also inactivated the enzyme irreversible in the 'unready' state without the requirement for reductants. The reaction of H2 uptake with methyl viologen was much more sensitive to inhibition than the H2/tritium exchange activity. EPR spectra of this preparation showed that the rates of decline were [3Fe-4S] signal greater than H2-uptake activity greater than Ni-A signal. Similar results were obtained when the protein was treated with Hg(II). The results demonstrate that the [3Fe-4S] cluster is not essential for H2-uptake activity with methyl viologen, but the integrity of [4Fe-4S] clusters is probably necessary to catalyze the reduction of methyl viologen with hydrogen. D. gigas hydrogenase was found to be highly resistant to digestion by proteases.

  14. The electro-mechanical integration of the NA62 GigaTracker time tagging pixel detector

    NASA Astrophysics Data System (ADS)

    Morel, M.; Kluge, A.; Aglieri Rinella, G.; Carassiti, V.; Ceccucci, A.; Daguin, J.; Fiorini, M.; Jarron, P.; Kaplon, J.; Mapelli, A.; Marchetto, F.; Noy, M.; Nuessle, G.; Perktold, L.; Petagna, P.; Riedler, P.

    2010-12-01

    The NA62 GigaTracker is a low mass time tagging hybrid pixel detector operating in a beam with a particle rate of 750 MHz. It consists of three stations with a sensor size of 60 × 27mm2 containing 18000 pixels, each 300 × 300μm2. The active area is connected to a matrix of 2 × 5 pixel ASICs, which time tag the arrival of the particles with a binning of 100 ps. The detector operates in vacuum at -20 to 0°C and the material budget per station must be below 0.5% X0. Due to the high radiation environment of 2 × 1014 1 MeV neutron equivalent cm-2/yr-1 it is planned to exchange the detector modules regularly. The low material budget, cooling requirements and the request for easy module access has driven the electro-mechanical integration of the GigaTracker, which is presented in this paper.

  15. GigaPan Technology to Enhance In-Class and In-Field Learning in Community College Settings

    NASA Astrophysics Data System (ADS)

    Villalobos, J. I.; Bentley, C.

    2014-12-01

    Community college students account for over 40% of all undergraduates in the United States as well as the majority of minority and non-traditional students attending undergraduate courses. Implementing innovative, cost effective, and formative pedagogies to the diverse backgrounds of students that typically enroll at a community is often a challenge. Interactive pedagogies in geology pose a unique challenge considering that students gain the most long-term knowledge when topics covered in a course are exposed to them in outdoor settings where they are allowed to explore and make connections. The ability to expose students to real world examples is challenging to many community college faculty considering that that many; lack funds or means for transportation of students, do not have administrative support on such endeavors, teach evening or night classes, or have a high percentage of students who are physically limited or have obligations to work and family. A joint collaborative between El Paso Community College (EPCC) and Northern Virginia Community College (NOVA) has explored the usage of GigaPan technology to create multi-layered online material to minimize these issues faced by many community college faculty and students. The primary layer of the online material is GigaPans of local geological sites that highlight large-scale structures in the El Paso, Texas region that are commonly used in local field trips and lab book material. The second layer is of Macro-GigaPans of hand samples of key outcrops from the primarily GigaPans which facilitate student learning, exploration, and ability to make connections by exploring smaller scale features of the primary layer. A third layer of online material, GigaPans of thin sections of hand samples (from secondary layers), and curriculum based on the GigaPans was then created to assist students in evaluating proposed hypotheses on the primary layers' geological origin. GigaPan cirriculum was utilized in introductory

  16. Critical update for the clinical use of L-carnitine analogs in cardiometabolic disorders.

    PubMed

    Mingorance, Carmen; Rodríguez-Rodríguez, Rosalía; Justo, María Luisa; Alvarez de Sotomayor, María; Herrera, María Dolores

    2011-01-01

    Acetyl-L-carnitine (ALC) and propionyl-L-carnitine (PLC) are two naturally occurring carnitine derivates formed by carnitine acetyltransferase. The beneficial cardiovascular effects of ALC and PLC have been extensively evaluated in animals and humans during the last 20 years. For instance, many clinical trials have suggested ALC and PLC as potential strategies in the management of peripheral arterial disease, heart and cerebral ischemia, and congestive heart failure. As a result, several experts have already aimed to revise the clinical evidence supporting the therapeutic use of ALC and PLC. On the basis of their conclusions, our aim was a critical review of the effectiveness of ALC and PLC in the treatment of cardiovascular diseases. Type 2 diabetes mellitus is an independent risk factor for the development of cardiovascular disease. Therefore we also describe recent studies that have addressed the emerging use of ALC and PLC amelioration of the insulin resistant state and its related morbidities.

  17. Polyamine content of long-keeping alcobaca tomato fruit.

    PubMed

    Dibble, A R; Davies, P J; Mutschler, M A

    1988-02-01

    Fruit of tomato landrace Alcobaca, containing the recessive allele alc, ripen more slowly, with a reduced level of ethylene production, and have prolonged keeping qualities. The levels of polyamines in pericarp tissues of alc and ;wild type' Alc (cv Rutgers and Alcobaca-red) fruit were measured by HPLC in relation to ripening. Putrescine was the predominant polyamine with a lower content of spermidine, while spermine was just detectable. The level of putrescine was high at the immature green stage and declined in the mature green stage. In Alc fruit the decline persisted but in alc fruit the putrescine level increased during ripening to a level similar to that present at the immature green stage. There was no pronounced change or difference in spermidine levels. The enhanced polyamine level in alc fruit may account for their ripening and storage characteristics.

  18. Larval and Post-Larval Stages of Pacific Oyster (Crassostrea gigas) Are Resistant to Elevated CO2

    PubMed Central

    R, Dineshram; Dennis, Choi K. S.; Adela, Li J.; Yu, Ziniu; Thiyagarajan, Vengatesen

    2013-01-01

    The average pH of surface oceans has decreased by 0.1 unit since industrialization and is expected to decrease by another 0.3–0.7 units before the year 2300 due to the absorption of anthropogenic CO2. This human-caused pH change is posing serious threats and challenges to the Pacific oyster (Crassostrea gigas), especially to their larval stages. Our knowledge of the effect of reduced pH on C. gigas larvae presently relies presumptively on four short-term (<4 days) survival and growth studies. Using multiple physiological measurements and life stages, the effects of long-term (40 days) exposure to pH 8.1, 7.7 and 7.4 on larval shell growth, metamorphosis, respiration and filtration rates at the time of metamorphosis, along with the juvenile shell growth and structure of the C. gigas, were examined in this study. The mean survival and growth rates were not affected by pH. The metabolic, feeding and metamorphosis rates of pediveliger larvae were similar, between pH 8.1 and 7.7. The pediveligers at pH 7.4 showed reduced weight-specific metabolic and filtration rates, yet were able to sustain a more rapid post-settlement growth rate. However, no evidence suggested that low pH treatments resulted in alterations to the shell ultrastructures (SEM images) or elemental compositions (i.e., Mg/Ca and Sr/Ca ratios). Thus, larval and post-larval forms of the C. gigas in the Yellow Sea are probably resistant to elevated CO2 and decreased near-future pH scenarios. The pre-adapted ability to resist a wide range of decreased pH may provide C. gigas with the necessary tolerance to withstand rapid pH changes over the coming century. PMID:23724027

  19. Larval and post-larval stages of Pacific oyster (Crassostrea gigas) are resistant to elevated CO2.

    PubMed

    Ginger, Ko W K; Vera, Chan B S; R, Dineshram; Dennis, Choi K S; Adela, Li J; Yu, Ziniu; Thiyagarajan, Vengatesen

    2013-01-01

    The average pH of surface oceans has decreased by 0.1 unit since industrialization and is expected to decrease by another 0.3-0.7 units before the year 2300 due to the absorption of anthropogenic CO2. This human-caused pH change is posing serious threats and challenges to the Pacific oyster (Crassostrea gigas), especially to their larval stages. Our knowledge of the effect of reduced pH on C. gigas larvae presently relies presumptively on four short-term (<4 days) survival and growth studies. Using multiple physiological measurements and life stages, the effects of long-term (40 days) exposure to pH 8.1, 7.7 and 7.4 on larval shell growth, metamorphosis, respiration and filtration rates at the time of metamorphosis, along with the juvenile shell growth and structure of the C. gigas, were examined in this study. The mean survival and growth rates were not affected by pH. The metabolic, feeding and metamorphosis rates of pediveliger larvae were similar, between pH 8.1 and 7.7. The pediveligers at pH 7.4 showed reduced weight-specific metabolic and filtration rates, yet were able to sustain a more rapid post-settlement growth rate. However, no evidence suggested that low pH treatments resulted in alterations to the shell ultrastructures (SEM images) or elemental compositions (i.e., Mg/Ca and Sr/Ca ratios). Thus, larval and post-larval forms of the C. gigas in the Yellow Sea are probably resistant to elevated CO2 and decreased near-future pH scenarios. The pre-adapted ability to resist a wide range of decreased pH may provide C. gigas with the necessary tolerance to withstand rapid pH changes over the coming century.

  20. Documentation and Evaluation of Depot Maintenance Cost System Coding and Reporting by Department of Defense Depots.

    DTIC Science & Technology

    1984-12-01

    quick and total distribution of goods to its worldwide customers [Ref. 31. Sacramento ALC and its host facility, McClellan AFB , employ nearly 18,000...the Air Force’worldwide. Sacramento ALC is physically located at McClellan Air Force Base in Sacramento , California. Other ALCs are located at Air Force...in this study is based on information . obtained from on-site visits to the Sacramento Air Logistics Center, Sacramento , Cali,.for-ia, and the Naval

  1. Gait and Balance in Treatment-Naive Active Alcoholics with and without a Lifetime Drug Codependence

    PubMed Central

    Fein, George; Smith, Stan; Greenstein, David

    2012-01-01

    Background Disturbed gait and balance are among the most consistent sequelae of chronic alcoholism. However, although a majority of alcoholics have never sought treatment, most investigations showing ataxia in alcohol dependent individuals have relied on samples drawn from treated populations. In addition, few studies have addressed the associations of codependence on other drugs with alcoholic gait and balance disturbance. Methods The present study employed the Walk-a-line Ataxia Battery (Fregly et al. 1972) to assess gait and balance in treatment-naive, actively drinking alcohol dependent men and women (TNA; n = 69) who were dependent on alcohol only (ALC; n = 43), or who also had a lifetime drug dependence (ALC+DRG; n = 26; i.e., methamphetamine, cocaine, opiates, and/or marijuana), compared with non-substance abusing controls (NSAC; n = 74). We also examined associations between lifetime alcohol use and age with gait and balance measures. Results Our main findings were 1) no evidence of disturbed gait and balance in ALC vs. NSAC and 2) significantly disturbed gait and balance in ALC+DRG, relative to both NSAC and ALC, along with steeper age-associated decline in gait and balance performance in ALC vs. ALC+DRG. Conclusions Our results provide evidence consistent with previous studies that TNA (without a lifetime drug codependence) may represent a population that is different and less impaired (including in gait and balance) than treated alcoholics. Additionally, we provide evidence that ALC+DRG, with greater alcohol use and family drinking density than ALC, have an accelerated effect of age on gait and balance disturbance compared to both NSAC and ALC. The ALC+DRG group likely represents a subset of TNA with different characteristics than ALC. PMID:22390787

  2. DoD Depot-Level Reparable Supply Chain Management: Process Effectiveness and Opportunities for Improvement

    DTIC Science & Technology

    2014-01-01

    Logistics Complex AMC Army Materiel Command AMCOM Aviation and Missile Life Cycle Management Command ANAD Anniston Army Depot AOIB Army Organic...Complex (ALC) (supply and maintenance), Oklahoma City ALC (supply and maintenance), Warner Robins ALC (supply), Anniston Army Depot, Corpus Christi...NIINs NOTE: CCAD = Corpus Christi Army Depot, TYAD = Tobyhanna Army Depot, LEAD = Letterkenny Army Depot, ANAD = Anniston Army Depot. RAND RR398-4.1 C

  3. Laser Depaint Technology for Aerospace Applications

    DTIC Science & Technology

    2011-05-01

    distribution unlimited. (Case number 88ABW-2011-1310) 3 Hand SandingChemical Stripping Problem Statement Plastic Media Blasting • US Air Force...Impacts: • Reduce stripping time and replace chemicals and blast media usage • Potential reductions at OC-ALC include: – 13,200 gallons paint stripper...Offices • Approval for production usage has been granted by 1of the 3 major weapon systems processed at OC-ALC • Based on positive results, Ogden ALC

  4. Biases in determining the diet of jumbo squid Dosidicus gigas (D' Orbigny 1835) (Cephalopoda: Ommastrephidae) off southern-central Chile (34°S-40°S)

    NASA Astrophysics Data System (ADS)

    Ibáñez, Christian M.; Arancibia, Hugo; Cubillos, Luis A.

    2008-12-01

    The diet of jumbo squid ( Dosidicus gigas) off southern-central Chile is described to examine potential biases in the determination of their main prey. Specimens were collected from catches using different fishing gear (jigging, trawl and purse-seine), from July 2003 to January 2004, and from December 2005 to October 2006. The stomach contents were analyzed in terms of frequency of occurrence, number, and weight of prey items and the diet composition was analyzed using Detrended Correspondence Analysis. In the industrial purse-seine fleet for jack mackerel ( Trachurus murphyi), the dominant prey of D. gigas was T. murphyi. In the industrial mid-trawl fishery for Patagonian grenadier ( Macruronus magellanicus), the dominant species in the diet of D. gigas was M. magellanicus. Similarly, Chilean hake ( Merluccius gayi) was the main prey in the diet of D. gigas obtained in the industrial trawl fishery for Chilean hake; and, in both artisanal fisheries (purse-seine for small pelagics and jigging), small pelagic fish and D. gigas were the main prey in the stomach contents of D. gigas. Cannibalism in D. gigas varied between different fleets and probably is related to stress behavior during fishing. The Detrended Correspondence Analysis ordination showed that the main prey in the diet of D. gigas is associated with the target species of the respective fishery. Consequently, biases are associated with fishing gear, leading to an overestimate in the occurrence of the target species in the diet. We recommend analyzing samples from jigging taken at the same time and place where the trawl and purse-seine fleets are operating to avoid this problem, and the application of new tools like stable isotope, heavy metal, and fatty acid signature analyses.

  5. A previously undescribed ostreid herpes virus 1 (OsHV-1) genotype detected in the pacific oyster, Crassostrea gigas, in Ireland.

    PubMed

    Lynch, S A; Carlsson, J; Reilly, A O; Cotter, E; Culloty, S C

    2012-10-01

    Significant mortalities of the Pacific oyster, Crassostrea gigas, have been reported worldwide since the 1950s. The impact these re-occurring mortality events have had on the C. gigas industry has highlighted the necessity to determine the factors that may be causing these mortalities. This study investigated the possible role of ostreid herpes virus (OsHV-1) in C. gigas mortalities over 2 successive summers at 2 study areas in Ireland. A single sample of adult C. gigas, which had been experiencing mortalities at one of the sites was screened. Successive cohorts of C. gigas spat obtained from a hatchery outside Ireland was relayed to both sites in 2003 and in 2004. Spat were screened each year prior to relaying. Samples were collected every 2 weeks and mortality counts were recorded and observed at both sites. Polymerase chain reaction (PCR) analysis and subsequent sequencing indicated that a previously undocumented variant genotype of OsHV-1 was present in the single cohort of adult C. gigas and in seed and juveniles at both sites, in both years. Analysis suggests that the Irish OsHV-1 μvar variant genotype is closely related to OsHV-1 μvar, first described in France in 2008.

  6. Effect of in situ delivery of acetyl-L-carnitine on peripheral nerve regeneration and functional recovery in transected sciatic nerve in rat.

    PubMed

    Farahpour, Mohammad Reza; Ghayour, Sina Jangkhahe

    2014-12-01

    The repair of peripheral nerve injuries is still one of the most challenging tasks and concerns in neurosurgery, plastic and orthopedic surgery. Effect of acetyl-L-carnitine (ALC) loaded chitosan conduit as an in situ delivery system of ALC in bridging the defects was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using a chitosan conduit (CHIT/ALC) filled with 10 μL ALC (100 ng/mL). In control group (CHIT), the conduit was filled with the same volume of the phosphate buffered solution. The regenerated fibers were studied 4, 8, 12 and 16 weeks after surgery. The functional and electrophysiological studies confirmed faster recovery of the regenerated axons in ALC treated than control group (P < 0.05). The mean ratios of gastrocnemius muscles weight were measured. There was statistically significant difference between the muscle weight ratios of CHIT/ALC and CHIT groups (P<0.05). Morphometric indices of regenerated fibers showed number and diameter of the myelinated fibers in CHIT/ALC were significantly higher than in control group. In immuohistochemistry, the location of reactions to S-100 in CHIT/ALC was clearly more positive than CHIT group. ALC when loaded in a chitosan conduit resulted in improvement of functional recovery and quantitative morphometric indices of sciatic nerve.

  7. Optimal Threshold and Time of Absolute Lymphocyte Count Assessment for Outcome Prediction after Bone Marrow Transplantation.

    PubMed

    Bayraktar, Ulas D; Milton, Denái R; Guindani, Michele; Rondon, Gabriela; Chen, Julianne; Al-Atrash, Gheath; Rezvani, Katayoun; Champlin, Richard; Ciurea, Stefan O

    2016-03-01

    The recovery pace of absolute lymphocyte count (ALC) is prognostic after hematopoietic stem cell transplantation. Previous studies have evaluated a wide range of ALC cutoffs and time points for predicting outcomes. We aimed to determine the optimal ALC value for outcome prediction after bone marrow transplantation (BMT). A total of 518 patients who underwent BMT for acute leukemia or myelodysplastic syndrome between 1999 and 2010 were divided into a training set and a test set to assess the prognostic value of ALC on days 30, 60, 90, 120, 180, as well as the first post-transplantation day of an ALC of 100, 200, 300, 400, 500, and 1000/μL. In the training set, the best predictor of overall survival (OS), relapse-free survival (RFS), and nonrelapse mortality (NRM) was ALC on day 60. In the entire patient cohort, multivariable analyses demonstrated significantly better OS, RFS, and NRM and lower incidence of graft-versus-host disease (GVHD) in patients with an ALC >300/μL on day 60 post-BMT, both including and excluding patients who developed GVHD before day 60. Among the patient-, disease-, and transplant-related factors assessed, only busulfan-based conditioning was significantly associated with higher ALC values on day 60 in both cohorts. The optimal ALC cutoff for predicting outcomes after BMT is 300/μL on day 60 post-transplantation.

  8. Absolute lymphocyte count at the end of induction therapy is a prognostic factor in childhood acute lymphoblastic leukemia.

    PubMed

    Hirase, Satoshi; Hasegawa, Daiichiro; Takahashi, Hironobu; Moriwaki, Kensuke; Saito, Atsuro; Kozaki, Aiko; Ishida, Toshiaki; Yanai, Tomoko; Kawasaki, Keiichiro; Yamamoto, Nobuyuki; Kubokawa, Ikuko; Mori, Takeshi; Hayakawa, Akira; Nishimura, Noriyuki; Nishio, Hisahide; Iijima, Kazumoto; Kosaka, Yoshiyuki

    2015-11-01

    Recent studies have reported that the absolute lymphocyte count (ALC) during induction therapy is predictive of treatment outcome in de novo acute lymphoblastic leukemia (ALL); however, the significance of ALC on outcomes remains controversial. In the present study, we assessed the significance of ALC at day 29 (ALC-29), the end of induction therapy, on outcomes in our Japanese cohort. The outcomes of 141 patients aged ≤18 years with newly diagnosed ALL who were enrolled on the JACLS ALL-02 at our hospitals were analyzed in terms of ALC-29. Patients with ALC-29 ≥750/μL (n = 81) had a superior 5-year EFS (95.2 ± 2.7 vs 84.3 ± 4.8 %, P = 0.016) and OS (100 vs 87.0 ± 4.7 %, P = 0.0062). A multivariate analysis identified ALC-29 ≥750/μL as a significant predictor of improved EFS and OS after controlling for confounding factors. A multiple linear regression model revealed a significant inverse relationship between the percentage of blasts in bone marrow on day 15 and ALC-29 (P = 0.005). These results indicate that ALC is a simple prognostic factor in childhood ALL, and, thus, has the potential to refine current risk algorithms.

  9. Determination/Validation of Technologies for Treatment/Recycle of Contaminated Sludges: Phase 1 - Site/Sludge Characterization and Laboratory Testing

    DTIC Science & Technology

    1998-08-01

    the feed solution upstream of pH adjustment. The alkalinity of borax will reduce the caustic consumption accordingly and the resultant boric acid ...0.1 is boric acid /borate (B(OH)3/B(OH);"). The major value of using a buffer is in achieving compliance residual metal levels with less caustic...metals S(C) Biosludge Minimization OC-ALC (C-1) Acid hydrolysis SA-ALC (C-2) Wet air oxidation WR-ALC (C-3) TEES S(D) Resource Recovery OC-ALC (D-1

  10. GigaGauss solenoidal magnetic field inside bubbles excited in under-dense plasma

    NASA Astrophysics Data System (ADS)

    Lécz, Zs.; Konoplev, I. V.; Seryi, A.; Andreev, A.

    2016-10-01

    This paper proposes a novel and effective method for generating GigaGauss level, solenoidal quasi-static magnetic fields in under-dense plasma using screw-shaped high intensity laser pulses. This method produces large solenoidal fields that move with the driving laser pulse and are collinear with the accelerated electrons. This is in contrast with already known techniques which rely on interactions with over-dense or solid targets and generates radial or toroidal magnetic field localized at the stationary target. The solenoidal field is quasi-stationary in the reference frame of the laser pulse and can be used for guiding electron beams. It can also provide synchrotron radiation beam emittance cooling for laser-plasma accelerated electron and positron beams, opening up novel opportunities for designs of the light sources, free electron lasers, and high energy colliders based on laser plasma acceleration.

  11. GigaGauss solenoidal magnetic field inside bubbles excited in under-dense plasma

    PubMed Central

    Lécz, Zs.; Konoplev, I. V.; Seryi, A.; Andreev, A.

    2016-01-01

    This paper proposes a novel and effective method for generating GigaGauss level, solenoidal quasi-static magnetic fields in under-dense plasma using screw-shaped high intensity laser pulses. This method produces large solenoidal fields that move with the driving laser pulse and are collinear with the accelerated electrons. This is in contrast with already known techniques which rely on interactions with over-dense or solid targets and generates radial or toroidal magnetic field localized at the stationary target. The solenoidal field is quasi-stationary in the reference frame of the laser pulse and can be used for guiding electron beams. It can also provide synchrotron radiation beam emittance cooling for laser-plasma accelerated electron and positron beams, opening up novel opportunities for designs of the light sources, free electron lasers, and high energy colliders based on laser plasma acceleration. PMID:27796327

  12. Genome-wide profiling of DNA methylation and gene expression in Crassostrea gigas male gametes

    PubMed Central

    Olson, Claire E.; Roberts, Steven B.

    2014-01-01

    DNA methylation patterns and functions are variable across invertebrate taxa. In order to provide a better understanding of DNA methylation in the Pacific oyster (Crassostrea gigas), we characterized the genome-wide DNA methylation profile in male gamete cells using whole-genome bisulfite sequencing. RNA-Seq analysis was performed to examine the relationship between DNA methylation and transcript expression. Methylation status of over 7.6 million CpG dinucleotides was described with a majority of methylated regions occurring among intragenic regions. Overall, 15% of the CpG dinucleotides were determined to be methylated and the mitochondrial genome lacked DNA methylation. Integrative analysis of DNA methylation and RNA-Seq data revealed a positive association between methylation status, both in gene bodies and putative promoter regions, and expression. This study provides a comprehensive characterization of the distribution of DNA methylation in the oyster male gamete tissue and suggests that DNA methylation is involved in gene regulatory activity. PMID:24987376

  13. [Determination of proximal chemical composition of squid (dosidicus gigas) and development of gel products].

    PubMed

    Abugoch, L; Guarda, A; Pérez, L M; Paredes, M P

    1999-06-01

    The good nutritional properties of meat from big squid (Dosidicus gigas) living on the Chilean coast, was determined through its proximal composition 70 cal/100 g fresh meat; 82.23 +/- 0.98% moisture; 15.32 +/- 0.93% protein; 1.31 +/- 0.12% ashes; 0.87 +/- 0.18% fat and 0.27% NNE (non-nitrogen extract). The big squid meat was used to develop a gel product which contained NaCl and TPP. It was necessary to use additives for gel preparation, such as carragenin or alginate or egg albumin, due to the lack of gelation properties of squid meat. Formulations containing egg albumin showed the highest gel force measured by penetration as compared to those that contained carragenin or alginate.

  14. The jumbo squid, Dosidicus gigas (Ommastrephidae), living in oxygen minimum zones II: Blood-oxygen binding

    NASA Astrophysics Data System (ADS)

    Seibel, Brad A.

    2013-10-01

    Dosidicus gigas is a large, metabolically active squid that migrates across a strong oxygen and temperature gradient in the Eastern Pacific. Here we analyze the oxygen-binding properties of the squid's respiratory protein (hemocyanin, Hc) that facilitate such activity. A high Hc-oxygen affinity, strong temperature dependence, and pronounced pH sensitivity (P50=0.009T2.03, pH 7.4; Bohr coefficient=ΔlogP50/ΔpH=-1.55+0.034T) of oxygen binding facilitate night-time foraging in the upper water column, and support suppressed oxygen demand in hypoxic waters at greater depths. Expanding hypoxia may act to alter the species habitable depth range. This analysis supports the contention that ocean acidification could limit oxygen carrying capacity in squids at warmer temperature leading to reduced activity levels or altered distribution.

  15. Impact of diuron on aneuploidy and hemocyte parameters in Pacific oyster, Crassostrea gigas.

    PubMed

    Bouilly, Karine; Bonnard, Marc; Gagnaire, Béatrice; Renault, Tristan; Lapègue, Sylvie

    2007-01-01

    Diuron is a substituted urea herbicide used for agricultural and nonagricultural weed control. Its widespread use and relatively slow breakdown led us to analyze its influence on aneuploidy level (lowered chromosome number in a percentage of somatic cells) and hemocyte parameters in Pacific oysters, Crassostrea gigas. Adult oysters were subjected to two diuron concentrations (300 ng L(-1) and 3 microg L(-1)) for 11 weeks. Significantly higher aneuploidy level was observed in diuron-treated oysters compared with the control. Furthermore, the observed impact on aneuploidy persisted to the next generation as offspring exhibited significantly higher aneuploidy levels when their parents had been exposed to diuron. Significant increases in hemocyte parameters (cell mortality, phagocytosis, granulocyte percentage, reactive oxygen species, and lysosome presence) of the adults were also observed after 4 weeks of diuron exposure. The effects observed on oyster aneuploidy level and hemocyte parameters could have serious environmental and practical consequences.

  16. Moissanite anvil cell design for giga-pascal nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Meier, Thomas; Herzig, Tobias; Haase, Jürgen

    2014-04-01

    A new design of a non-magnetic high-pressure anvil cell for nuclear magnetic resonance (NMR) experiments at Giga-Pascal pressures is presented, which uses a micro-coil inside the pressurized region for high-sensitivity NMR. The comparably small cell has a length of 22 mm and a diameter of 18 mm, so it can be used with most NMR magnets. The performance of the cell is demonstrated with external-force vs. internal-pressure experiments, and the cell is shown to perform well at pressures up to 23.5 GPa using 800 μm 6H-SiC large cone Boehler-type anvils. 1H, 23Na, 27Al, 69Ga, and 71Ga NMR test measurements are presented, which show a resolution of better than 4.5 ppm, and an almost maximum possible signal-to-noise ratio.

  17. Gravity and light effects on the circadian clock of a desert beetle, Trigonoscelis gigas

    NASA Technical Reports Server (NTRS)

    Hoban-Higgins, T. M.; Alpatov, A. M.; Wassmer, G. T.; Rietveld, W. J.; Fuller, C. A.

    2003-01-01

    Circadian function is affected by exposure to altered ambient force environments. Under non-earth gravitational fields, both basic features of circadian rhythms and the expression of the clock responsible for these rhythms are altered. We examined the activity rhythm of the tenebrionid beetle, Trigonoscelis gigas, in conditions of microgravity (microG; spaceflight), earth's gravity (1 G) and 2 G (centrifugation). Data were recorded under a light-dark cycle (LD), constant light (LL), and constant darkness (DD). Free-running period (tau) was significantly affected by both the gravitational field and ambient light intensity. In DD, tau was longer under 2 G than under either 1 G or microG. In addition, tauLL was significantly different from tauDD under microG and 1 G, but not under 2 G.

  18. Realized detection and capture probabilities for giant gartersnakes (Thamnophis gigas) using modified floating aquatic funnel traps

    USGS Publications Warehouse

    Halstead, Brian J.; Skalos, Shannon M.; Casazza, Michael L.; Wylie, Glenn D.

    2015-01-01

    Detection and capture probabilities for giant gartersnakes (Thamnophis gigas) are very low, and successfully evaluating the effects of variables or experimental treatments on giant gartersnake populations will require greater detection and capture probabilities than those that had been achieved with standard trap designs. Previous research identified important trap modifications that can increase the probability of snakes entering traps and help prevent the escape of captured snakes. The purpose of this study was to quantify detection and capture probabilities obtained using the most successful modification to commercially available traps to date (2015), and examine the ability of realized detection and capture probabilities to achieve benchmark levels of precision in occupancy and capture-mark-recapture studies.

  19. Evaluation of Giga-bit Ethernet instrumentation for SalSA electronics readout

    NASA Astrophysics Data System (ADS)

    Varner, Gary S.; Murakami, Laine; Ridley, David; Zhu, Chaopin; Gorham, Peter

    2005-12-01

    An instrumentation prototype for acquiring high-speed transient data from an array of high bandwidth antennas is presented. Multi-kilometer cable runs complicate acquisition of such large bandwidth radio signals from an extensive antenna array. Solutions using analog fiber optic links are being explored though are very expensive. We propose an inexpensive solution that allows for individual operation of each antenna element, operating at potentially high local self-trigger rates. Digitized data packets are transmitted to the surface via commercially available Giga-bit Ethernet hardware. Events are then reconstructed on a computer farm by sorting the received packets using standard networking gear, eliminating the need for custom, very high speed trigger hardware. Such a system is completely scalable and leverages the enormous capital investment made by the telecommunications industry. Test results from a demonstration prototype are presented.

  20. Temporal and maternal effects on reproductive ecology of the giant gartersnake (Thamnophis gigas)

    USGS Publications Warehouse

    Halstead, B.J.; Wylie, G.D.; Casazza, M.L.; Coates, P.S.

    2011-01-01

    We used mixed-effects models to examine relationships of reproductive characteristics of the giant gartersnake (Thamnophis gigas) to improve population modeling and conservation planning for this species. Neonates from larger litters had lower mass, and mass of neonates also was affected by random variation among mothers. Length of mother did not affect relative mass of litters; however, our data suggest that longer mothers expended less reproductive effort per offspring than shorter mothers. We detected random variation in length of neonates among mothers, but these lengths were not related to length of mother or size of litter. Mean size of litter varied among years, but little evidence existed for a relationship between size of litter or mass of litter and length of mother. Sex ratios of neonates did not differ from 1:1.

  1. Ontogeny and water temperature influences the antiviral response of the Pacific oyster, Crassostrea gigas.

    PubMed

    Green, Timothy J; Montagnani, Caroline; Benkendorff, Kirsten; Robinson, Nick; Speck, Peter

    2014-01-01

    Disease is caused by a complex interaction between the pathogen, environment, and the physiological status of the host. Determining how host ontogeny interacts with water temperature to influence the antiviral response of the Pacific oysters, Crassostrea gigas, is a major goal in understanding why juvenile Pacific oysters are dying during summer as a result of the global emergence of a new genotype of the Ostreid herpesvirus, termed OsHV-1 μvar. We measured the effect of temperature (12 vs 22 °C) on the antiviral response of adult and juvenile C. gigas injected with poly I:C. Poly I:C up-regulated the expression of numerous immune genes, including TLR, MyD88, IκB-1, Rel, IRF, MDA5, STING, SOC, PKR, Viperin and Mpeg1. At 22 °C, these immune genes showed significant up-regulation in juvenile and adult oysters, but the majority of these genes were up-regulated 12 h post-injection for juveniles compared to 26 h for adults. At 12 °C, the response of these genes was completely inhibited in juveniles and delayed in adults. Temperature and age had no effect on hemolymph antiviral activity against herpes simplex virus (HSV-1). These results suggest that oysters rely on a cellular response to minimise viral replication, involving recognition of virus-associated molecular patterns to induce host cells into an antiviral state, as opposed to producing broad-spectrum antiviral compounds. This cellular response, measured by antiviral gene expression of circulating hemocytes, was influenced by temperature and oyster age. We speculate whether the vigorous antiviral response of juveniles at 22 °C results in an immune-mediated disorder causing mortality.

  2. Pollutant effects on Pacific oyster, Crassostrea gigas (Thunberg), hemocytes: screening of 23 molecules using flow cytometry.

    PubMed

    Gagnaire, B; Thomas-Guyon, H; Burgeot, Th; Renault, T

    2006-01-01

    The shellfish industry is an important economic activity in France, occurring mostly in estuarine zones subject to pollution due to anthropogenic activities. The harmful effects of pollutants on species inhabiting these estuarine zones are not well known. Among marine species, bivalve mollusks--particularly Pacific oyster, Crassostrea gigas--may serve a model of interest. The species is sedentary and filter-feeding, which favors bioaccumulation of pollutants in their tissues. Oysters may be suitable for studies on disturbance by pollutants of physiological activities, among which defense mechanisms are poorly documented in bivalves. In this study, effects of pollutants on hemocyte functions were monitored in Pacific oyster, C. gigas. Hemocytes were exposed in vitro to selected pollutants. The strategy for investigating the effects of pollutants on hemocyte functions is based on several biomarkers, which is more relevant than that of published papers based on single-endpoint experiments. Pollutants belonging to the most important groups of xenobiotics (PAHs, PCBs, and pesticides) were selected and their effect on hemocyte activities was analyzed using flow cytometry. Twenty-three pollutants were tested and eight of them showed significant modulation of hemocyte activities. PAHs and PCB 77 induced a decrease of hemocyte activity after an incubation periods of 4 and 24 h at 200 micro mol/L. Three pesticides (2,4D, paraoxon, and chlorothalonil) modulated hemocyte activities. A mixture of eight pesticides also decreased phagocytotic activity. This study is one of the first to investigate the effects of so many pollutants on hemocyte functions at the same time and therefore allows a real comparison of different pollutant effects.

  3. Evidence for accumulation of Synechococcus elongatus (Cyanobacteria: Cyanophyceae) in the tissues of the oyster Crassostrea gigas (Mollusca: Bivalvia).

    PubMed

    Avila-Poveda, Omar Hernando; Torres-Ariño, Alejandra; Girón-Cruz, Diego Ademir; Cuevas-Aguirre, Angel

    2014-10-01

    Cyanobacteria appear to have direct relations with mollusks in several aspects. This is the first time, distinguishing Gram-negative cyanoprokaryotic Synechococcus elongatus as bright yellow-gold autofluorescence by Lillie's and Hiss' staining methods on paraffin-embedded tissues of Crassostrea gigas. Three diets: cyanoprokaryotes, cyanoprokaryotes with microalgae, and only microalgae were evaluated. Cyanoprokaryotes were intact, densely bundled, and immersed in the cytosol of the digestive gland, connective tissue, mantle, and gonad of C. gigas, revealing an accumulation systemic without tissue damage observed by histology. Unexpectedly, cyanoprokaryotes were slightly most accumulated with microalgae diet by each of the tissues of the C. gigas than with any other diets. Cyanoprokaryotes tend to be in mean slightly higher in the digestive gland than in any other tissues respectively for each diet, although these values are closely similar to connective tissue. A possible order of exposure of the oyster tissues to accumulation of cyanoprokaryotes was digestive gland, connective tissue, mantle, and gonad. Thereby, the digestive gland could be the major target tissue for the accumulation. Our observations provide a valuable insight regarding the ability of cyanoprokaryotes to penetrate, spread, and remain inside the oyster tissues, suggesting for S. elongatus: (1) a pre-accumulation in oyster tissues from the natural environment, (2) a phagocytosis and/or endocytosis process rather than ingestion and extracellular digestion, (3) an apparent cellular division in the cytosol of oyster tissues, (4) an apparent inter-tissue movement, and (5) a possible endosymbiosis between C. gigas and S. elongatus. Hereby, it is possible that S. elongatus have a well-developed host-endobiont relationship with oysters, and thereby support future work toward a description of the escape and spreading mechanisms of S. elongatus inside the tissues of mollusks, and put forward questions as

  4. New Insight for the Genetic Evaluation of Resistance to Ostreid Herpesvirus Infection, a Worldwide Disease, in Crassostrea gigas.

    PubMed

    Dégremont, Lionel; Lamy, Jean-Baptiste; Pépin, Jean-François; Travers, Marie-Agnès; Renault, Tristan

    2015-01-01

    The Pacific oyster, Crassostrea gigas, is the most important commercial oyster species cultivated in the world. Meanwhile, the ostreid herpesvirus 1 (OsHV-1) is one of the major pathogens affecting the Pacific oyster, and numerous mortality outbreaks related to this pathogen are now reported worldwide. To assess the genetic basis of resistance to OsHV-1 infection in spat C. gigas and to facilitate breeding programs for such a trait, if any exist, we compared the mortality of half- and full-sib families using three field methods and a controlled challenge by OsHV-1 in the laboratory. In the field, three methods were tested: (A) one family per bag; (B) one family per small soft mesh bag and all families inside one bag; (C) same as the previous methods but the oysters were individually labelled and then mixed. The mean mortality ranged from 80 to 82% and was related to OsHV-1 based on viral DNA detection. The narrow-sense heritability for mortality, and thus OsHV-1 resistance, ranged from 0.49 to 0.60. The high positive genetic correlations across the field methods suggested no genotype by environment interaction. Ideally, selective breeding could use method B, which is less time- and space-consuming. The narrow sense heritability for mortality under OsHV-1 challenge was 0.61, and genetic correlation between the field and the laboratory was ranged from 0.68 to 0.75, suggesting a weak genotype by environment interaction. Thus, most of families showing the highest survival performed well in field and laboratory conditions, and a similar trend was also observed for families with the lowest survival. In conclusion, this is the first study demonstrating a large additive genetic variation for resistance to OsHV-1 infection in C. gigas, regardless of the methods used, which should help in selective breeding to improve resistance to viral infection in C. gigas.

  5. New Insight for the Genetic Evaluation of Resistance to Ostreid Herpesvirus Infection, a Worldwide Disease, in Crassostrea gigas

    PubMed Central

    Dégremont, Lionel; Lamy, Jean-Baptiste; Pépin, Jean-François; Travers, Marie-Agnès; Renault, Tristan

    2015-01-01

    The Pacific oyster, Crassostrea gigas, is the most important commercial oyster species cultivated in the world. Meanwhile, the ostreid herpesvirus 1 (OsHV-1) is one of the major pathogens affecting the Pacific oyster, and numerous mortality outbreaks related to this pathogen are now reported worldwide. To assess the genetic basis of resistance to OsHV-1 infection in spat C. gigas and to facilitate breeding programs for such a trait, if any exist, we compared the mortality of half- and full-sib families using three field methods and a controlled challenge by OsHV-1 in the laboratory. In the field, three methods were tested: (A) one family per bag; (B) one family per small soft mesh bag and all families inside one bag; (C) same as the previous methods but the oysters were individually labelled and then mixed. The mean mortality ranged from 80 to 82% and was related to OsHV-1 based on viral DNA detection. The narrow-sense heritability for mortality, and thus OsHV-1 resistance, ranged from 0.49 to 0.60. The high positive genetic correlations across the field methods suggested no genotype by environment interaction. Ideally, selective breeding could use method B, which is less time- and space-consuming. The narrow sense heritability for mortality under OsHV-1 challenge was 0.61, and genetic correlation between the field and the laboratory was ranged from 0.68 to 0.75, suggesting a weak genotype by environment interaction. Thus, most of families showing the highest survival performed well in field and laboratory conditions, and a similar trend was also observed for families with the lowest survival. In conclusion, this is the first study demonstrating a large additive genetic variation for resistance to OsHV-1 infection in C. gigas, regardless of the methods used, which should help in selective breeding to improve resistance to viral infection in C. gigas. PMID:26039375

  6. Populations of Pacific oysters Crassostrea gigas respond variably to elevated CO2 and predation by Morula marginalba.

    PubMed

    Wright, John M; Parker, Laura M; O'Connor, Wayne A; Williams, Mark; Kube, Peter; Ross, Pauline M

    2014-06-01

    Ocean acidification is anticipated to decrease calcification and increase dissolution of shelled molluscs. Molluscs with thinner and weaker shells may be more susceptible to predation, but not all studies have measured negative responses of molluscs to elevated pCO2. Recent studies measuring the response of molluscs have found greater variability at the population level than first expected. Here we investigate the impact of acidification on the predatory whelk Morula marginalba and genetically distinct subpopulations of the Pacific oyster Crassostrea gigas. Whelks and eight family lines of C. gigas were separately exposed to ambient (385 ppm) and elevated (1000 ppm) pCO2 for 6 weeks. Following this period, individuals of M. marginalba were transferred into tanks with oysters at ambient and elevated pCO2 for 17 days. The increase in shell height of the oysters was on average 63% less at elevated compared to ambient pCO2. There were differences in shell compression strength, thickness, and mass among family lines of C. gigas, with sometimes an interaction between pCO2 and family line. Against expectations, this study found increased shell strength in the prey and reduced shell strength in the predator at elevated compared to ambient pCO2. After 10 days, the whelks consumed significantly more oysters regardless of whether C. gigas had been exposed to ambient or elevated CO2, but this was not dependent on the family line and the effect was not significant after 17 days. Our study found an increase in predation after exposure of the predator to predicted near-future levels of estuarine pCO2.

  7. Identification and characterisation of an ostreid herpesvirus-1 microvariant (OsHV-1 µ-var) in Crassostrea gigas (Pacific oysters) in Australia.

    PubMed

    Jenkins, Cheryl; Hick, Paul; Gabor, Melinda; Spiers, Zoe; Fell, Shayne A; Gu, Xingnian; Read, Andrew; Go, Jeffrey; Dove, Michael; O'Connor, Wayne; Kirkland, Peter D; Frances, Jane

    2013-07-22

    Between November 2010 and January 2011, triploid Crassostrea gigas (Pacific oysters) cultivated in the Georges River, New South Wales, experienced >95% mortality. Mortalities also occurred in wild diploid C. gigas in the Georges River and shortly thereafter in the adjacent Parramatta River estuary upstream from Sydney Harbour. Neighbouring Saccostrea glomerata (Sydney rock oysters) did not experience mortalities in either estuary. Surviving oysters were collected to investigate the cause of mortalities. Histologically all oysters displayed significant pathology, and molecular testing revealed a high prevalence of ostreid herpesvirus-1 (OsHV-1). Quantitative PCR indicated that many C. gigas were carrying a high viral load at the time of sampling, while the load in S. glomerata was significantly lower (p < 0.001). Subsequent in situ hybridisation experiments confirmed the presence of a herpesvirus in C. gigas but not S. glomerata tissues, suggesting that S. glomerata is not susceptible to infection with OsHV-1. Naïve sentinel triploid C. gigas placed in the Georges River estuary in January 2011 quickly became infected and experienced nearly 100% mortality within 2 wk of exposure, indicating the persistence of the virus in the environment. Phylogenetic analysis of sequences derived from the C2/C6 region of the virus revealed that the Australian strain of OsHV-1 belongs to the microvariant (µ-var) cluster, which has been associated with severe mortalities in C. gigas in other countries since 2008. Environmental data revealed that the Woolooware Bay outbreaks occurred during a time of considerable environmental disturbance, with increased water temperatures, heavy rainfall, a toxic phytoplankton bloom and the presence of a pathogenic Vibrio sp. all potentially contributing to oyster stress. This is the first confirmed report of OsHV-1 µ-var related C. gigas mortalities in Australia.

  8. The jumbo squid, Dosidicus gigas (Ommastrephidae), living in oxygen minimum zones I: Oxygen consumption rates and critical oxygen partial pressures

    NASA Astrophysics Data System (ADS)

    Trueblood, Lloyd A.; Seibel, Brad A.

    2013-10-01

    Dosidicus gigas is a large, metabolically active, epipelagic squid known to undertake diel vertical migrations across a large temperature and oxygen gradient in the Eastern Pacific. Hypoxia is known to cause metabolic suppression in D. gigas. However, the precise oxygen level at which metabolic suppression sets in is unknown. Here we describe a novel ship-board swim tunnel respirometer that was used to measure metabolic rates and critical oxygen partial pressures (Pcrit) for adult squids (2-7kg). Metabolic rate measurements were validated by comparison to the activity of the Krebs cycle enzyme, citrate synthase, in mantle muscle tissue (2-17kg). We recorded a mean routine metabolic rate of 5.91μmolg-1h-1 at 10°C and 12.62μmolg-1h-1 at 20°C. A temperature coefficient, Q10, of 2.1 was calculated. D. gigas had Pcrits of 1.6 and 3.8kPa at 10 and 20°C, respectively. Oxygen consumption rate (MO2) varied with body mass (M) according to MO2=11.57M-0.12±0.03 at 10°C. Citrate synthase activity varied with body mass according to Y=9.32M-0.19±0.02.

  9. Ostreid herpesvirus 1 detection and relationship with Crassostrea gigas spat mortality in France between 1998 and 2006.

    PubMed

    Garcia, Céline; Thébault, Anne; Dégremont, Lionel; Arzul, Isabelle; Miossec, Laurence; Robert, Maeva; Chollet, Bruno; François, Cyrille; Joly, Jean-Pierre; Ferrand, Sylvie; Kerdudou, Nolwenn; Renault, Tristan

    2011-06-02

    Since its molecular characterisation, Ostreid herpesvirus 1 (OsHV-1) has been regularly detected in Crassostrea gigas in France. Although its pathogenicity was demonstrated on larval stages, its involvement during mortality outbreaks at the juvenile stage was highly suspected but not evidenced. To investigate mortality outbreaks, the French National Network for Surveillance and Monitoring of Mollusc Health (REPAMO) carried out two surveys in juvenile C. gigas. The first survey lasted from 1998 to 2006 and was an epidemiological inquiry occurring when oyster farmers reported mortality outbreaks. The second survey, a longitudinal one, was set up in 1998 to complete the network observations on OsHV-1. Data analysis showed a specific pattern of mortality outbreaks associated with OsHV-1 detection. Ostreid herpesvirus 1 detection mainly appeared during the summer, suggesting the influence of the seawater temperature on its occurrence. It mostly presented a patchy distribution in the field in contrast to the nursery. Significant relationship between OsHV-1 detection and spat mortality was found, preferentially in sheltered and closed environments. The longitudinal survey confirmed most of the network observations. Although subsequent works particularly epidemiological surveys would be useful to confirm the causal link between the detection of OsHV-1 and the mortality outbreaks in juvenile C. gigas, the role of OsHV-1 in oyster mortality is progressing.

  10. Ostreid herpesvirus 1 detection and relationship with Crassostrea gigas spat mortality in France between 1998 and 2006

    PubMed Central

    2011-01-01

    Since its molecular characterisation, Ostreid herpesvirus 1 (OsHV-1) has been regularly detected in Crassostrea gigas in France. Although its pathogenicity was demonstrated on larval stages, its involvement during mortality outbreaks at the juvenile stage was highly suspected but not evidenced. To investigate mortality outbreaks, the French National Network for Surveillance and Monitoring of Mollusc Health (REPAMO) carried out two surveys in juvenile C. gigas. The first survey lasted from 1998 to 2006 and was an epidemiological inquiry occurring when oyster farmers reported mortality outbreaks. The second survey, a longitudinal one, was set up in 1998 to complete the network observations on OsHV-1. Data analysis showed a specific pattern of mortality outbreaks associated with OsHV-1 detection. Ostreid herpesvirus 1 detection mainly appeared during the summer, suggesting the influence of the seawater temperature on its occurrence. It mostly presented a patchy distribution in the field in contrast to the nursery. Significant relationship between OsHV-1 detection and spat mortality was found, preferentially in sheltered and closed environments. The longitudinal survey confirmed most of the network observations. Although subsequent works particularly epidemiological surveys would be useful to confirm the causal link between the detection of OsHV-1 and the mortality outbreaks in juvenile C. gigas, the role of OsHV-1 in oyster mortality is progressing. PMID:21635731

  11. Isolation of the pituitary gonadotrophic α-subunit hormone of the giant amazonian fish: pirarucu (Arapaima gigas).

    PubMed

    Faria, M T; Carvalho, R F; Sevilhano, T C A; Oliveira, N A J; Silva, C F P; Oliveira, J E; Soares, C R J; Garcez, R; Santo, P R E; Bartolini, P

    2013-06-01

    The cDNAs of the α-subunit of the pituitary gonadotrophic hormones (GTHα) of fish of the order Osteoglossiformes or the superorder Osteoglossomorpha have never been sequenced. For a better understanding the phylogenetic diversity and evolution of PGHα in fish and for future biotechnological synthesis of the gonadotrophic hormones (ag-FSH and ag-LH), of Arapaima gigas, one of the largest freshwater fishes of the world, its GTHα cDNA was synthesized by reverse transcriptase and the polymerase chain reaction starting from total pituitary RNA. The ag-GTHα-subunit was found to be encoded by 348 bp, corresponding to a protein of 115 amino acids, with a putative signal peptide of 24 amino acids and a mature peptide of 91 amino acids. Ten cysteine residues, responsible for forming 5 disulfide linkages, 2 putative N-linked glycosylation sites and 3 proline residues, were found to be conserved on the basis of the known sequences of vertebrate gonadotrophic hormones. Phylogenetic analysis, based on the amino acid sequences of 38 GTHα-subunits, revealed the highest identity of A. gigas with members of the Acipenseriformes, Anguilliformes, Siluriformes and Cypriniformes (87.1-89.5 %) and the lowest with Gadiformes and Cyprinodontiformes (55.0 %). The obtained phylogenetic tree agrees with previous analysis of teleostei, since A. gigas, of the order of Osteoglossiformes, appears as the sister group of Clupeocephala, while Elopomorpha forms the most basal group of all other teleosts.

  12. Relationship between single nucleotide polymorphism of glycogen synthase gene of Pacific oyster Crassostrea gigas and its glycogen content

    NASA Astrophysics Data System (ADS)

    Liu, Siwei; Li, Qi; Yu, Hong; Kong, Lingfeng

    2017-02-01

    Glycogen is important not only for the energy supplementary of oysters, but also for human consumption. High glycogen content can improve the stress survival of oyster. A key enzyme in glycogenesis is glycogen synthase that is encoded by glycogen synthase gene GYS. In this study, the relationship between single nucleotide polymorphisms (SNPs) in coding regions of Crassostrea gigas GYS (Cg-GYS) and individual glycogen content was investigated with 321 individuals from five full-sib families. Single-strand conformation polymorphism (SSCP) procedure was combined with sequencing to confirm individual SNP genotypes of Cg-GYS. Least-square analysis of variance was performed to assess the relationship of variation in glycogen content of C. gigas with single SNP genotype and SNP haplotype. As a consequence, six SNPs were found in coding regions to be significantly associated with glycogen content ( P < 0.01), from which we constructed four main haplotypes due to linkage disequilibrium. Furthermore, the most effective haplotype H2 (GAGGAT) had extremely significant relationship with high glycogen content ( P < 0.0001). These findings revealed the potential influence of Cg-GYS polymorphism on the glycogen content and provided molecular biological information for the selective breeding of good quality traits of C. gigas.

  13. Lethal dose and clinical signs of Aeromonas hydrophila in Arapaima gigas (Arapaimidae), the giant fish from Amazon.

    PubMed

    Dias, Marcia K R; Sampaio, Luciana S; Proietti-Junior, Aldo A; Yoshioka, Eliane T O; Rodrigues, Dália P; Rodriguez, Anselmo F R; Ribeiro, Ricardo A; Faria, Fernando S E D V; Ozório, Rodrigo O A; Tavares-Dias, Marcos

    2016-05-30

    Aeromonas hydrophila is causing substantial economic losses in world aquaculture. This study determined the tolerance limit (LD50-96h) of A. hydrophila in Arapaima gigas, and also investigated the clinical signs after intradermal inoculation. Arapaima gigas fingerlings were inoculated intraperitoneally with 0 (control), 1.0×10(5), 1.0×10(6), 1.0×10(7), 1.0×10(9) and 1.0×10(10)CFU/mL of A. hydrophila for the determination of LD50-96h, which was 1.8×10(8)CFU/mL. In another trial with intradermal inoculation of 1.8×10(8)CFU/mL A. hydrophila, there was a 91.6% of mortality between 8 and 23h, and several clinical signs were found. As follows: depigmentation in the tegument, lesions in the tail and fins, loss of balance, reduction of respiratory movements, hemorrhagic foci, necrotic hemorrhages in the kidney, liver and swim bladder, splenomegaly, ascites in the abdominal cavity and hyperemia, enlargement of the gall bladder, among other clinical signs observed. The results showed that A. gigas has a relative tolerance to A. hydrophila when compared to other Neotropical fish species.

  14. Genetic variation assessed with microsatellites in mass selection lines of the Pacific oyster ( Crassostrea gigas) in China

    NASA Astrophysics Data System (ADS)

    Wang, Xubo; Li, Qi; Yu, Hong; Kong, Lingfeng

    2016-12-01

    Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding programs in China were examined at ten polymorphic microsatellite loci to assess the level of allelic diversity and estimate the effective population size. These data were compared with those of their base population. The results showed that the genetic variation of the four generations were maintained at high levels with an average allelic richness of 18.8-20.6, and a mean expected heterozygosity of 0.902-0.921. They were not reduced compared with those of their base population. Estimated effective population sizes based on temporal variances in microsatellite frequencies were smaller to that of sex ratio-corrected broodstock count estimates. Using a relatively large number of broodstock and keeping an equal sex ratio in the broodstock each generation may have contributed to retaining the original genetic diversity and maintaining relatively large effective population size. The results obtained in this study showed that the genetic variation was not affected greatly by mass selection progress and high genetic variation still existed in the mass selection lines, suggesting that there is still potential for increasing the gains in future generations of C. gigas. The present study provided important information for future genetic improvement by selective breeding, and for the design of suitable management guidelines for genetic breeding of C. gigas.

  15. Range expansion of moose in arctic Alaska linked to warming and increased shrub habitat

    USGS Publications Warehouse

    Tape, Ken D.; Gustine, David D.; Reuss, Roger W.; Adams, Layne G.; Clark, Jason A.

    2016-01-01

    Twentieth century warming has increased vegetation productivity and shrub cover across northern tundra and treeline regions, but effects on terrestrial wildlife have not been demonstrated on a comparable scale. During this period, Alaskan moose (Alces alces gigas) extended their range from the boreal forest into tundra riparian shrub habitat; similar extensions have been observed in Canada (A. a. andersoni) and Eurasia (A. a. alces). Northern moose distribution is thought to be limited by forage availability above the snow in late winter, so the observed increase in shrub habitat could be causing the northward moose establishment, but a previous hypothesis suggested that hunting cessation triggered moose establishment. Here, we use recent changes in shrub cover and empirical relationships between shrub height and growing season temperature to estimate available moose habitat in Arctic Alaska c. 1860. We estimate that riparian shrubs were approximately 1.1 m tall c. 1860, greatly reducing the available forage above the snowpack, compared to 2 m tall in 2009. We believe that increases in riparian shrub habitat after 1860 allowed moose to colonize tundra regions of Alaska hundreds of kilometers north and west of previous distribution limits. The northern shift in the distribution of moose, like that of snowshoe hares, has been in response to the spread of their shrub habitat in the Arctic, but at the same time, herbivores have likely had pronounced impacts on the structure and function of these shrub communities. These northward range shifts are a bellwether for other boreal species and their associated predators.

  16. GigA and GigB are Master Regulators of Antibiotic Resistance, Stress Responses and Virulence in Acinetobacter baumannii.

    PubMed

    Gebhardt, Michael J; Shuman, Howard A

    2017-03-06

    A critical component of bacterial pathogenesis is the ability of an invading organism to sense and adapt to the harsh environment imposed by the host's immune system. This is especially important for opportunistic pathogens, such as Acinetobacter baumannii, a nutritionally versatile, environmental organism that has recently gained attention as a life-threatening human pathogen. The emergence of A. baumannii is closely linked to antibiotic resistance and many contemporary isolates are multi-drug resistant (MDR). Unlike many other MDR pathogens, the molecular mechanisms underlying A. baumannii pathogenesis remain largely unknown. We report here the characterization of two recently identified virulence determinants, GigA and GigB, which comprise a signal transduction pathway required for surviving environmental stresses, causing infection and antibiotic resistance. Through transcriptome analysis we show that GigA and GigB coordinately regulate the expression of many genes and are required for generating an appropriate transcriptional response during antibiotic exposure. Genetic and biochemical data demonstrate a direct link between GigA and GigB and the nitrogen phosphotransferase system (PTS(Ntr)), establishing a novel connection between a novel stress response module and a well-conserved metabolic sensing pathway. Based on results presented here, we propose that GigA and GigB are master regulators of a global stress response in A. baumannii and coupling this pathway with the PTS(Ntr) allows A. baumannii to integrate cellular metabolic status with external environmental cues.IMPORTANCE Opportunistic pathogens, including Acinetobacter baumannii, encounter many harsh environments during the infection cycle, including antibiotic exposure and the hostile environment within a host. While development of antibiotic resistance in A. baumannii has been well studied, how this organism senses and responds to environmental cues remains largely unknown. Herein, we investigate two

  17. Bare sclera resection followed by mitomycin C and/or autograft limbus conjunctiva in the surgery for pterygium: a Meta-analysis

    PubMed Central

    Long, Tan; Li, Zhi

    2015-01-01

    AIM To evaluate the recurrence and complications after bare sclera resection (BSR) combined with mitomycin C (MMC) treatment and/or autograft limbus conjunctiva (ALC) in the surgery for pterygium. METHODS Meta-analysis was used to evaluate the differences in patient outcomes between BSR of pterygium with or without MMC and/or ALC. All included studies were randomized trials of patients with pterygium who received BSR followed by MMC and/or ALC in the surgery. The recurrence of pterygium and other complications resulting from different treatments were extracted for analysis. RESULTS Thirteen studies met the inclusion criteria. The recurrence of pterygium with intraoperative (IO) MMC was higher than that with ALC (OR=2.38, 95% confidence interval 1.45-3.91, I2=29%). Postoperative MMC resulted in an incidence of recurrence similar to that of ALC (OR=0.66, 95% confidence interval 0.30-1.42, I2=0%), and IO MMC treatment in combination with ALC produced similar patient outcomes to ALC alone (OR=0.41, 95% confidence interval 0.16-1.01, I2=16%). Other complications such as punctate epitheliopathy, scleral thinning and ischemia, irritation and persistent epithelium defect, were more common in patients in the MMC group as compared to those treated with ALC. CONCLUSION The recurrence of pterygium with BSR followed by ALC is lower than that of BSR followed by MMC, and the incidence of other complications is lower. While ALC is a more effective strategy for treating pterygium, the quality of the ALC transplant should be considered when the patient has a history of glaucoma. PMID:26558227

  18. Early lymphocyte recovery at 28 d post-transplant is predictive of reduced risk of relapse in patients with acute myeloid leukemia transplanted with peripheral blood stem cell grafts.

    PubMed

    Michelis, Fotios V; Messner, Hans A; Loach, David; Uhm, Jieun; Gupta, Vikas; Lipton, Jeffrey H; Seftel, Matthew D; Kuruvilla, John; Kim, Dennis D

    2014-10-01

    Allogeneic hematopoietic cell transplantation (HCT) is potentially curative for acute myeloid leukemia (AML). Impact of lymphocyte recovery on post-transplant outcomes has been suggested but reports are conflicting. We evaluated the impact of lymphocyte recovery at 28 d post-HCT in 191 AML patients using peripheral blood stem cells as graft. Patients were divided into those with absolute lymphocyte count (ALC) ≥ 0.5 × 10(9) /L (n = 111, 58%; high ALC group) and those with ALC < 0.5 × 10(9) /L (n = 80, 42%; low ALC group), at day 28 post-transplant. With a median follow-up of 49 months, overall survival (OS) was significantly improved in the high ALC group (59% at 3 yr) vs. patients with low ALC (40% at 3 yr, P = 0.03). Cumulative incidence of relapse (CIR) was significantly lower in the high ALC group (16% at 3 yr) vs. low ALC group (36% at 3 yr, P = 0.001). Multivariable analysis for CIR demonstrated high ALC group as an independent factor decreasing relapse risk (P = 0.03, HR = 0.49, 95% CI = 0.26-0.92). Multivariable analysis for OS and non-relapse mortality did not demonstrate ALC ≥ 0.5 × 10(9) /L at 28 d post-transplant to be predictive. We conclude that lymphocyte recovery with ALC ≥ 0.5 × 10(9) /L at day 28 post-transplant is associated with less relapse in AML patients undergoing allogeneic peripheral blood HCT, but without survival benefit.

  19. Potential utility of soluble p3-alcadein α plasma levels as a biomarker for sporadic Alzheimer's disease.

    PubMed

    Kamogawa, Kenji; Kohara, Katsuhiko; Tabara, Yasuharu; Takita, Rie; Miki, Tetsuro; Konno, Tomoko; Hata, Saori; Suzuki, Toshiharu

    2012-01-01

    Alcadeins (Alcs) constitute a family of neuronal type I membrane proteins (α, β, γ) that share identical localization and function to the amyloid-β protein precursor (AβPP) in the brain. Alcs are proteolyzed in neurons through successive cleavages via secretases, resulting in non-aggregative p3-Alc, where p3 corresponds to the AβPP-fragment. We found p3-Alcα detected in human plasma reflected the pathological process of amyloid-β accumulation in Alzheimer's disease (AD) patients and therefore investigated the utility of p3-Alcα as a plasma biomarker in AD. We measured p3-Alcα plasma levels in 83 sporadic-AD, 18 mild cognitive impaired (MCI), and 24 control subjects using the sandwich-ELISA system. Pooled samples with previously published data (171 AD and 45 controls) were also analyzed. The plasma p3-Alcα concentrations in patients with AD and MCI were significantly higher compared with control subjects (224.7 ± 40.4, 223.3 ± 53.9, and 189.1 ± 32.9 pg/ml, respectively; p = 0.0012). In AD patients, the plasma p3-Alcα concentration significantly correlated with age (r = 0.23, p = 0.037) and serum creatinine levels (r = 0.23, p = 0.0012). Even after adjusting for confounding factors of age, gender, renal function, and ApoE-ε4, high plasma p3-Alcα levels were correlated with significant AD risk, with an odds ratio 1.47 (95% confidence interval: 1.18-1.93, p = 0.0019) for every 10 pg/ml increase. Pooled analysis further confirmed these findings. Increased plasma p3-Alcα, evident in the early stages of cognitive impairment, suggests that Alc metabolites are useful plasma biomarkers of AD.

  20. Connected components labeling for giga-cell multi-categorical rasters

    NASA Astrophysics Data System (ADS)

    Netzel, Pawel; Stepinski, Tomasz F.

    2013-09-01

    Labeling of connected components in an image or a raster of non-imagery data is a fundamental operation in fields of pattern recognition and machine intelligence. The bulk of effort devoted to designing efficient connected components labeling (CCL) algorithms concentrated on the domain of binary images where labeling is required for a computer to recognize objects. In contrast, in the Geographical Information Science (GIS) a CCL algorithm is mostly applied to multi-categorical rasters in order to either convert a raster to a shapefile, or for statistical characterization of individual clumps. Recently, it has become necessary to label connected components in very large, giga-cell size, multi-categorical rasters but performance of existing CCL algorithms lacks sufficient speed to accomplish such task. In this paper we present a modification to the popular two-scan CCL algorithm that enables labeling of giga-cell size, multi-categorical rasters. Our approach is to apply a divide-and-conquer technique coupled with parallel processing to a standard two-scan algorithm. For specificity, we have developed a variant of a standard CCL algorithm implemented as r.clump in GRASS GIS. We have established optimal values of data blocks (stemming from the divide-and-conquer technique) and optimal number of computational threads (stemming from parallel processing) for a new algorithm called r.clump3p. The performance of the new algorithm was tested on a series of rasters up to 160 Mcells in size; for largest size test raster a speed up over the original algorithm is 74 times. Finally, we have applied the new algorithm to the National Land Cover Dataset 2006 raster with 1.6×1010 cells. Labeling this raster took 39 h using two-processors, 16 cores computer and resulted in 221,718,501 clumps. Estimated speed up over the original algorithm is 450 times. The r.clump3p works within the GRASS environment and is available in the public domain.

  1. Sufentanil citrate immobilization of Alaskan moose calves.

    PubMed

    Kreeger, Terry J; Kellie, Kalin A

    2012-10-01

    Free-ranging Alaskan moose calves (Alces alces gigas) were immobilized with 0.12 mg/kg sufentanil (S; n=16), 0.12 mg/kg sufentanil plus 0.27 mg/kg xylazine (SX; n=11), or 0.007 mg/kg carfentanil plus 0.36 mg/kg xylazine (CX; n=13). Immobilants were antagonized with 1.2 mg/kg naltrexone (S) or 1.2 mg/kg naltrexone plus 2.4 mg/kg tolazoline (SX, CX). There were no differences in induction (P ≥ 0.29) or processing (P ≥ 0.44) times between groups. Moose given either S or SX had significantly shorter recovery times than moose given CX (P=0.001) and recovery times from S were shorter than from SX (P=0.02). Oxygen saturation values for all groups averaged 85 ± 8%, but were significantly higher (P=0.048) for CX (89 ± 7%) than for S (82 ± 8%). Based on these data, sufentanil at 0.1 mg/kg or sufentanil at 0.1 mg/kg plus xylazine at 0.25 mg/kg could provide effective remote immobilization for Alaskan moose calves and could be substituted for carfentanil or thiafentanil should the need arise.

  2. Combined metabolome and proteome analysis of the mantle tissue from Pacific oyster Crassostrea gigas exposed to elevated pCO2.

    PubMed

    Wei, Lei; Wang, Qing; Ning, Xuanxuan; Mu, Changkao; Wang, Chunlin; Cao, Ruiwen; Wu, Huifeng; Cong, Ming; Li, Fei; Ji, Chenglong; Zhao, Jianmin

    2015-03-01

    Ocean acidification (OA) has been found to affect an array of normal physiological processes in mollusks, especially posing a significant threat to the fabrication process of mollusk shell. In the current study, the impact of exposure to elevated pCO2 condition was investigated in mantle tissue of Crassostrea gigas by an integrated metabolomic and proteomic approach. Analysis of metabolome and proteome revealed that elevated pCO2 could affect energy metabolism in oyster C. gigas, marked by differentially altered ATP, succinate, MDH, PEPCK and ALDH levels. Moreover, the up-regulated calponin-2, tropomyosins and myosin light chains indicated that elevated pCO2 probably caused disturbances in cytoskeleton structure in mantle tissue of oyster C. gigas. This work demonstrated that a combination of proteomics and metabolomics could provide important insights into the effects of OA at molecular levels.

  3. Safety evaluation of Angelica gigas: Genotoxicity and 13-weeks oral subchronic toxicity in rats.

    PubMed

    Yun, Jun-Won; Che, Jeong-Hwan; Kwon, Euna; Kim, Yun-Soon; Kim, Seung-Hyun; You, Ji-Ran; Kim, Woo Ho; Kim, Hyeon Hoe; Kang, Byeong-Cheol

    2015-08-01

    As a well-known traditional medicine, Angelica gigas (AG) and its active constituents, including decursin and decursinol, have been shown to possess several health beneficial properties such as anti-bacterial, immunostimulating, anti-tumor, neuroprotective, anti-nociceptive and anti-amnestic activities. However, there is lack of toxicity studies to assess potential toxicological concerns, especially long-term toxicity and genotoxicity, regarding the AG extract. Therefore, the safety of AG extract was assessed in subchronic toxicity and genotoxicity assays in accordance with the test guidelines published by the Organization for Economic Cooperation and Development. In a subchronic toxicity study for 13 weeks (125, 250, 500, 1000 and 2000 mg/kg body weight, delivered by gavage), data revealed no significant adverse effects of the AG extract in food consumption, body weight, mortality, hematology, biochemistry, necropsy, organ weight and histopathology throughout the study in male and female rats. These results suggest that no observed adverse effect level of the AG extract administered orally was determined to be greater than 2000 mg/kg/day, the highest dose tested. In addition, a battery of tests including Ames test, in vitro chromosome aberration assay and in vivo micronucleus assay suggested that the AG extract was not genotoxic. In conclusion, the AG extract appears to be safe as a traditional medicine for oral consumption.

  4. Decursin from Angelica gigas suppresses RANKL-induced osteoclast formation and bone loss.

    PubMed

    Wang, Xin; Zheng, Ting; Kang, Ju-Hee; Li, Hua; Cho, Hyewon; Jeon, Raok; Ryu, Jae-Ha; Yim, Mijung

    2016-03-05

    Osteoclasts are the only cells capable of breaking down bone matrix, and excessive activation of osteoclasts is responsible for bone-destructive diseases. In this study, we investigated the effects of decursin from extract of Angelica gigas root on receptor activator of nuclear factor kappa B ligand (RANKL)-induced osteoclast formation using mouse bone marrow-derived macrophages (BMMs). Decursin inhibited RANKL-induced osteoclast formation without cytotoxicity. In particular, decursin maintains the characteristics of macrophages by blocking osteoclast differentiation by RANKL. Furthermore, the RANKL-stimulated bone resorption was diminished by decursin. Mechanistically, decursin blocked the RANKL-triggered ERK mitogen-activated protein kinases (MAPK) phosphorylation, which results in suppression of c-Fos and the nuclear factor of activated T cells (NFATc1) expression. In accordance with the in vitro study, decursin reduced lipopolysaccharide (LPS)- or ovariectomy (OVX)-induced bone loss in vivo. Therefore, decursin exerted an inhibitory effect on osteoclast formation and bone loss in vitro and in vivo. Decursin could be useful for the treatment of bone diseases associated with excessive bone resorption.

  5. Decursin from Angelica gigas Nakai Inhibits B16F10 Melanoma Growth Through Induction of Apoptosis.

    PubMed

    Kim, Byung Soo; Seo, Hyobin; Kim, Ha-Jeong; Bae, Sang Mun; Son, Hye-Nam; Lee, Yoon Jeong; Ryu, Sungpil; Park, Rang-Woon; Nam, Ju-Ock

    2015-10-01

    Decursin, a bioactive phytochemical isolated from Angelica gigas Nakai (danggwi), has shown preclinical anticancer efficacy in various cancer models. However, the antitumor effect of decursin in melanoma models remains undefined. The antitumor activities of decursin were investigated in B16F10 cells in vitro and in vivo. In this study, we show that treatment with decursin inhibited cell proliferation in a dose-dependent manner in B16F10 cells, but not in normal cells. Decursin also induced apoptosis in B16F10 cells, as determined by annexin V-staining assay and transferase-mediated nick-end labeling (TUNEL) staining assay. Decursin increased the phosphorylation of p38 as well as the expression of Bax while decreasing the phosphorylation of extracellular signaling-regulated kinase (ERK) and the expression of Bcl-2 in B16F10 cells. Moreover, decursin activated caspase-3 in B16F10 cells and xenograft tumor tissue. Together, these findings support further investigations into the potential use of decursin in the treatment of melanoma cells.

  6. Inheritance and Variation of Genomic DNA Methylation in Diploid and Triploid Pacific Oyster (Crassostrea gigas).

    PubMed

    Jiang, Qun; Li, Qi; Yu, Hong; Kong, Lingfeng

    2016-02-01

    DNA methylation is an important epigenetic mechanism that could be responsive to environmental changes indicating a potential role in natural selection and adaption. In order to evaluate an evolutionary role of DNA methylation, it is essential to first gain a better insight into inheritability. To address this question, this study investigated DNA methylation variation from parents to offspring in the Pacific oyster Crassostrea gigas using fluorescent-labeled methylation-sensitive amplified polymorphism (F-MSAP) analysis. Most of parental methylated loci were stably transmitted to offspring segregating following Medelian expectation. However, methylated loci deviated more often than non-methylated loci and offspring showed a few de novo methylated loci indicating DNA methylation changes from parents to offspring. Interestingly, some male-specific methylated loci were found in this study which might help to explore sex determination in oyster. Despite environmental stimuli, genomic stresses such as polyploidization also can induce methylation changes. This study also compared global DNA methylation level and individual methylated loci between diploid and triploid oysters. Results showed no difference in global methylation state but a few ploidy-specific loci were detected. DNA methylation variation during polyploidization was less than autonomous methylation variation from parents to offspring.

  7. The simple neuroendocrine-immune regulatory network in oyster Crassostrea gigas mediates complex functions

    PubMed Central

    Liu, Zhaoqun; Wang, Lingling; Zhou, Zhi; Sun, Ying; Wang, Mengqiang; Wang, Hao; Hou, Zhanhui; Gao, Dahai; Gao, Qiang; Song, Linsheng

    2016-01-01

    The neuroendocrine-immune (NEI) regulatory network is a complex system, which plays an indispensable role in the immunity of the host. In the present study, the bioinformatical analysis of the transcriptomic data from oyster Crassostrea gigas and further biological validation revealed that oyster TNF (CgTNF-1 CGI_10018786) could activate the transcription factors NF-κB and HSF (heat shock transcription factor) through MAPK signaling pathway, and then regulate apoptosis, redox reaction, neuro-regulation and protein folding in oyster haemocytes. The activated immune cells then released neurotransmitters including acetylcholine, norepinephrine and [Met5]-enkephalin to regulate the immune response by arising the expression of three TNF (CGI_10005109, CGI_10005110 and CGI_10006440) and translocating two NF-κB (Cgp65, CGI_10018142 and CgRel, CGI_10021567) between the cytoplasm and nuclei of haemocytes. Neurotransmitters exhibited the immunomodulation effects by influencing apoptosis and phagocytosis of oyster haemocytes. Acetylcholine and norepinephrine could down-regulate the immune response, while [Met5]-enkephalin up-regulate the immune response. These results suggested that the simple neuroendocrine-immune regulatory network in oyster might be activated by oyster TNF and then regulate the immune response by virtue of neurotransmitters, cytokines and transcription factors. PMID:27193598

  8. Introduction, establishment and expansion of the Pacific oyster Crassostrea gigas in the Oosterschelde (SW Netherlands)

    NASA Astrophysics Data System (ADS)

    Smaal, A. C.; Kater, B. J.; Wijsman, J.

    2009-03-01

    The Pacific oyster Crassostrea gigas was first introduced as an exotic species by oyster farmers in 1964 in the Oosterschelde estuary (SW Netherlands). The initial phase is not well documented but first natural spatfall was recorded in 1975. Excessive spatfall occurred in 1976 and this is considered the start of the expansion phase of the wild oysters. Oyster beds in intertidal and subtidal areas of the Oosterschelde estuary have been growing since. The development in the intertidal area has been reconstructed by using aerial photography, validated by ground truth in 2000-2002. In the subtidal areas extensive oyster beds have been detected by using side scan sonar; on hard substrates along the dikes coverage with oysters up to 90% locally has been recorded by scuba diving surveys. Expansion has also occurred into adjacent water bodies including the Wadden Sea. By forming resistant reefs the oysters induce structural changes in the ecosystem. It is concluded that bed area is still expanding while decrease of the fraction live animals may indicate adjustment of the stock size to the local conditions.

  9. Zooming to the centre of the Milky Way - GigaGalaxy Zoom phase 2

    NASA Astrophysics Data System (ADS)

    2009-09-01

    The second of three images of ESO's GigaGalaxy Zoom project has just been released online. It is a new and wonderful 340-million-pixel vista of the central parts of our home galaxy as seen from ESO's Paranal Observatory with an amateur telescope. This 34 by 20-degree wide image provides us with a view as experienced by amateur astronomers around the world. However, its incredible beauty and appeal owe much to the quality of the observing site and the skills of Stéphane Guisard, the world-renowned astrophotographer, who is also an ESO engineer. This second image directly benefits from the quality of Paranal's sky, one of the best on the planet, where ESO's Very Large Telescope is located. In addition, Guisard has drawn on his professional expertise as an optical engineer specialising in telescopes, a rare combination in the world of astrophotographers. Guisard, as head of the optical engineering team at Paranal, is responsible for ensuring that the Very Large Telescope has the best optical performance possible. To create this stunning, true-colour mosaic of the Galactic Centre region, Guisard assembled about 1200 individual images, totalling more than 200 hours of exposure time, collected over 29 nights, during Guisard's free time, while working during the day at Paranal [1]. The image shows the region spanning the sky from the constellation of Sagittarius (the Archer) to Scorpius (the Scorpion). The very colourful Rho Ophiuchi and Antares region is a prominent feature to the right, although much darker areas, such as the Pipe and Snake nebulae also stand out. The dusty lane of our Milky Way runs obliquely through the image, dotted with remarkable bright, reddish nebulae, such as the Lagoon and the Trifid Nebulae, as well as NGC 6357 and NGC 6334. This dark lane also hosts the very centre of our Galaxy, where a supermassive black hole is lurking. "The area I have depicted in this image is an incredibly rich region of the sky, and the one I find most beautiful

  10. Effect of cadmium on the defense response of Pacific oyster Crassostrea gigas to Listonella anguillarum challenge

    NASA Astrophysics Data System (ADS)

    Cong, Ming; Lü, Jiasen; Wu, Huifeng; Zhao, Jianmin

    2013-09-01

    Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The activities of several important defensive enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), Na+, K+ -ATPase in gills and hepatopancreas, and phenoloxidase-like (POL) enzyme in hemolymph were assayed. In addition, the expression levels of several genes, including heat shock protein 90 (HSP90), metallothionein (MT), and bactericidal/permeability increasing (BPI) protein were quantified by fluorescent quantitative PCR. The enzyme activities of SOD, ACP, POL, and GPx in hepatopancreas, and the expression of HSP90 were down-regulated, whereas GPx activity in the gill, Na+, K+-ATPase activities in both tissues, and MT expression was increased in Cdexposed oysters post L. anguillarum challenge. However, BPI expression was not significantly altered by co-stress of L. anguillarum infection and cadmium exposure. Our results suggest that cadmium exposure alters the oysters' immune responses and energy metabolism following vibrio infection.

  11. The simple neuroendocrine-immune regulatory network in oyster Crassostrea gigas mediates complex functions

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoqun; Wang, Lingling; Zhou, Zhi; Sun, Ying; Wang, Mengqiang; Wang, Hao; Hou, Zhanhui; Gao, Dahai; Gao, Qiang; Song, Linsheng

    2016-05-01

    The neuroendocrine-immune (NEI) regulatory network is a complex system, which plays an indispensable role in the immunity of the host. In the present study, the bioinformatical analysis of the transcriptomic data from oyster Crassostrea gigas and further biological validation revealed that oyster TNF (CgTNF-1 CGI_10018786) could activate the transcription factors NF-κB and HSF (heat shock transcription factor) through MAPK signaling pathway, and then regulate apoptosis, redox reaction, neuro-regulation and protein folding in oyster haemocytes. The activated immune cells then released neurotransmitters including acetylcholine, norepinephrine and [Met5]-enkephalin to regulate the immune response by arising the expression of three TNF (CGI_10005109, CGI_10005110 and CGI_10006440) and translocating two NF-κB (Cgp65, CGI_10018142 and CgRel, CGI_10021567) between the cytoplasm and nuclei of haemocytes. Neurotransmitters exhibited the immunomodulation effects by influencing apoptosis and phagocytosis of oyster haemocytes. Acetylcholine and norepinephrine could down-regulate the immune response, while [Met5]-enkephalin up-regulate the immune response. These results suggested that the simple neuroendocrine-immune regulatory network in oyster might be activated by oyster TNF and then regulate the immune response by virtue of neurotransmitters, cytokines and transcription factors.

  12. Linkage disequilibrium in wild and cultured populations of Pacific oyster ( Crassostrea gigas)

    NASA Astrophysics Data System (ADS)

    Guo, Xiang; Li, Qi; Kong, Lingfeng; Yu, Hong

    2016-04-01

    Linkage disequilibrium (LD) can be applied for mapping the actual genes responsible for variation of economically important traits through association mapping. The feasibility and efficacy of association studies are strongly dependent on the extent of LD which determines the number and density of markers in the studied population, as well as the experimental design for an association analysis. In this study, we first characterized the extent of LD in a wild population and a cultured mass-selected line of Pacific oyster ( Crassostrea gigas). A total of 88 wild and 96 cultured individuals were selected to assess the level of genome-wide LD with 53 microsatellites, respectively. For syntenic marker pairs, no significant association was observed in the wild population; however, three significant associations occurred in the cultured population, and the significant LD extended up to 12.7 cM, indicating that strong artificial selection is a key force for substantial increase of genome-wide LD in cultured population. The difference of LD between wild and cultured populations showed that association studies in Pacific oyster can be achieved with reasonable marker densities at a relatively low cost by choosing an association mapping population. Furthermore, the frequent occurrence of LD between non-syntenic loci and rare alleles encourages the joint application of linkage analysis and LD mapping when mapping genes in oyster. The information on the linkage disequilibrium in the cultured population is useful for future association mapping in oyster.

  13. Ostreid herpesvirus type 1 replication and host response in adult Pacific oysters, Crassostrea gigas.

    PubMed

    Segarra, Amélie; Baillon, Laury; Tourbiez, Delphine; Benabdelmouna, Abdellah; Faury, Nicole; Bourgougnon, Nathalie; Renault, Tristan

    2014-10-08

    Since 2008, massive mortality outbreaks associated with OsHV-1 detection have been reported in Crassostrea gigas spat and juveniles in several countries. Nevertheless, adult oysters do not demonstrate mortality in the field related to OsHV-1 detection and were thus assumed to be more resistant to viral infection. Determining how virus and adult oyster interact is a major goal in understanding why mortality events are not reported among adult Pacific oysters. Dual transcriptomics of virus-host interactions were explored by real-time PCR in adult oysters after a virus injection. Thirty-nine viral genes and five host genes including MyD88, IFI44, IkB2, IAP and Gly were measured at 0.5, 10, 26, 72 and 144 hours post infection (hpi). No viral RNA among the 39 genes was detected at 144 hpi suggesting the adult oysters are able to inhibit viral replication. Moreover, the IAP gene (oyster gene) shows significant up-regulation in infected adults compared to control adults. This result suggests that over-expression of IAP could be a reaction to OsHV-1 infection, which may induce the apoptotic process. Apoptosis could be a main mechanism involved in disease resistance in adults. Antiviral activity of haemolymph against herpes simplex virus (HSV-1) was not significantly different between infected adults versus control.

  14. Response of the Pacific oyster Crassostrea gigas, Thunberg 1793, to pesticide exposure under experimental conditions.

    PubMed

    Collin, Hélène; Meistertzheim, Anne-Leila; David, Elise; Moraga, Dario; Boutet, Isabelle

    2010-12-01

    Pesticide run-off into the ocean represents a potential threat to marine organisms, especially bivalves living in coastal environments. However, little is known about the effects of environmentally relevant concentrations of pesticides at the individual level. In this study, the suppression subtractive hybridisation technique was used to discover the main physiological function affected by a cocktail of three pesticides (lindane, metolachlor and carbofuran) in the Pacific oyster Crassostrea gigas. Two oyster populations exposed to different pollution levels in the wild were investigated. The pesticide concentrations used to induce stress were close to those found in the wild. In a time course experiment, the expression of three genes implicated in iron metabolism and oxidative stress as well as that of two ubiquitous stress proteins was examined. No clear regulation of gene or protein expression was found, potentially due to a low-dose effect. However, we detected a strong site- and organ-specific response to the pesticides. This study thus (1) provides insight into bivalve responses to pesticide pollution at the level of the transcriptome, which is the first level of response for organisms facing pollution, and (2) raises interesting questions concerning the importance of the sites and organs studied in the toxicogenomic field.

  15. Effects of ocean acidification on immune responses of the Pacific oyster Crassostrea gigas.

    PubMed

    Wang, Qing; Cao, Ruiwen; Ning, Xuanxuan; You, Liping; Mu, Changkao; Wang, Chunlin; Wei, Lei; Cong, Ming; Wu, Huifeng; Zhao, Jianmin

    2016-02-01

    Ocean acidification (OA), caused by anthropogenic CO2emissions, has been proposed as one of the greatest threats in marine ecosystems. A growing body of evidence shows that ocean acidification can impact development, survival, growth and physiology of marine calcifiers. In this study, the immune responses of the Pacific oyster Crassostrea gigas were investigated after elevated pCO2 exposure for 28 days. The results demonstrated that OA caused an increase of apoptosis and reactive oxygen species (ROS) production in hemocytes. Moreover, elevated pCO2 had an inhibitory effect on some antioxidant enzyme activities and decreased the GSH level in digestive gland. However, the mRNA expression pattern of several immune related genes varied depending on the exposure time and tissues. After exposure to pCO2 at ∼2000 ppm for 28 days, the mRNA expressions of almost all tested genes were significantly suppressed in gills and stimulated in hemocytes. Above all, our study demonstrated that elevated pCO2 have a significant impact on the immune systems of the Pacific oyster, which may constitute as a potential threat to increased susceptibility of bivalves to diseases.

  16. A comparative study of piscine defense: The scales of Arapaima gigas, Latimeria chalumnae and Atractosteus spatula.

    PubMed

    Sherman, Vincent R; Quan, Haocheng; Yang, Wen; Ritchie, Robert O; Meyers, Marc A

    2016-10-04

    We compare the characteristics of the armored scales of three large fish, namely the Arapaima gigas (arapaima), Latimeria chalumnae (coelacanth), and Atractosteus spatula (alligator gar), with specific focus on their unique structure-mechanical property relationships and their specialized ability to provide protection from predatory pressures, with the ultimate goal of providing bio-inspiration for manmade materials. The arapaima has flexible and overlapping cycloid scales which consist of a tough Bouligand-type arrangement of collagen layers in the base and a hard external mineralized surface, protecting it from piranha, a predator with extremely sharp teeth. The coelacanth has overlapping elasmoid scales that consist of adjacent Bouligand-type pairs, forming a double-twisted Bouligand-type structure. The collagenous layers are connected by collagen fibril struts which significantly contribute to the energy dissipation, so that the scales have the capability to defend from predators such as sharks. The alligator gar has inflexible articulating ganoid scales made of a hard and highly mineralized enamel-like outer surface and a tough dentine-like bony base, which resist powerful bite forces of self-predation and attack by alligators. The structural differences between the three scales correspond with the attack of their predators, and show refined mechanisms which may be imitated and incorporated into superior bioinspired and biomimetic designs that are specialized to resist specific modes of predation.

  17. Omega-3 fatty acids incorporated colloidal systems for the delivery of Angelica gigas Nakai extract.

    PubMed

    Lee, Jeong-Jun; Park, Ju-Hwan; Lee, Jae-Young; Jeong, Jae Young; Lee, Song Yi; Yoon, In-Soo; Kang, Wie-Soo; Kim, Dae-Duk; Cho, Hyun-Jong

    2016-04-01

    Omega-3 (ω-3) fish oil-enriched colloidal systems were developed for the oral delivery of Angelica gigas Nakai (AGN) extract (ext). By constructing a pseudo-ternary phase diagram, the composition of oil-in-water (o/w) microemulsion (ME) systems based on ω-3 (oil), Labrasol (surfactant), and water was determined. AGN ext was dissolved into the ME system and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) was added to the ME formulation in order to enhance the mucosal absorption of the pharmacologically active ingredients in the AGN ext. The droplet size of AGN-loaded MEs was 205-277 nm and their morphology was spherical. The release of major components of AGN, decursin (D) and decursinol angelate (DA), from ME formulations in pH 1.2 and 6.8 buffers was significantly greater (P<0.05) than that from the AGN suspension group. The pharmacokinetic properties of AGN-loaded MEs in rats were evaluated by measuring decursinol (DOH) concentrations in plasma after oral administration. TPGS-included ME (F2) resulted in significantly greater (P<0.05) systemic exposure of DOH than that with ME without TPGS (F1), AGN ext+TPGS, and AGN in suspension. Severe toxicity of F1 and F2 on the intestinal epithelium was not observed by histological staining. The colloidal carriers described herein are promising delivery systems for oral administration of AGN ext.

  18. Discoloration and lipid deterioration of farmed giant catfish (Pangasianodon gigas) muscle during refrigerated storage.

    PubMed

    Rawdkuen, S; Jongjareonrak, A; Benjakul, S; Chaijan, M

    2008-04-01

    Discoloration and lipid deterioration of farmed giant catfish (Pangasianodon gigas) muscle during 14 d refrigerated storage were investigated. Lipid deterioration, lipolysis, and lipid oxidation in both dorsal and ventral muscles increased as storage time increased. A progressive formation of primary lipid oxidation products monitored by the increase in conjugated dienes (CD) was observed (P < 0.05) and the increase in thiobarbituric reactive substances (TBARS), an index of secondary lipid oxidation products, was noticeable throughout the storage (P < 0.05). The pH of both dorsal and ventral muscles tended to increase as storage time continued (P < 0.05). A gradual increase in free fatty acid (FFA) formation was found within the first 10 d of refrigerated storage (P < 0.05), suggesting hydrolysis induced by lipases and phospholipases. However, a sharp decrease in FFA content was observed at the end of storage. Refrigerated storage also resulted in changes in redness index of both dorsal and ventral muscles. These changes were coincidental with the changes in metmyoglobin content. Therefore, the discoloration and lipid changes in giant catfish muscle during refrigerated storage depended on the muscle type and might be related to the difference in composition between dorsal and ventral muscles.

  19. Identification and quantification of hepatotoxic pyrrolizidine alkaloids in the Ethiopian medicinal plant Solanecio gigas (Asteraceae).

    PubMed

    Asres, K; Sporer, F; Wink, M

    2007-09-01

    The pyrrolizidine alkaloid content of Solanecio gigas (Vatke) C. Jeffrey (Asteraceae), an Ethiopian medicinal plant widely used for the treatment of colic, diarrhea, gout, otitis media, typhoid fever, and noted for its wound dressing and antiabortifacient activities was studied. The flower and leaf extracts contained 0.19% and 0.14% alkaloids (dry weight), respectively. GLC-MS analysis indicated that all the alkaloids in the flowers are pyrrolizidine alkaloids (PAs), whereas the leaves contain other type of alkaloids with PAs occurring in low concentrations. Roughly, 80% and 90% of the total PAs in the flowers and the leaves, respectively, were shown to occur as N-oxides. Eighteen alkaloids were detected in the flower extract with the retronecine type twelve-membered macrocyclic diesters integerrimine, senecionine and usaramine comprising 82% of the total PA content. Analysis of the PA profile of the leaves indicated that it has a simpler pattern than the one observed for the flowers. Only five PAs were detected in the leaves with integerrimine making up about 50% of the total PAs. Quantification of the PA content by GLC showed that the flowers and leaves contain 3321.21 and 84.84 microg per 10 g of dried plant material, respectively. These results indicate that users of this herb are at high risk of poisoning since the most toxic twelve membered macrocyclics of the retronecine type are the dominant PAs in the plant.

  20. Investigation of jumbo squid (Dosidicus gigas) skin gelatin peptides for their in vitro antioxidant effects.

    PubMed

    Mendis, Eresha; Rajapakse, Niranjan; Byun, Hee-Guk; Kim, Se-Kwon

    2005-09-09

    Peptides derived from tryptic hydrolysate of jumbo squid (Dosidicus gigas) skin gelatin were assessed for their antioxidant properties in different in vitro assay systems. The hydrolysate itself exhibited a strong lipid peroxidation inhibition and it was much higher than that of natural antioxidant, alpha-tocopherol. In addition, it could scavenge highly active free radicals in oxidative systems, in the order of hydroxyl and carbon-centered radicals. Two representative peptides with comparatively higher antioxidant potency were purified and characterized as Phe-Asp-Ser-Gly-Pro-Ala-Gly-Val-Leu (880.18 Da) and Asn-Gly-Pro-Leu-Gln-Ala-Gly-Gln-Pro-Gly-Glu-Arg (1241.59 Da). Furthermore, viability of radical-mediated oxidation-induced human lung fibroblasts was enhanced following the treatment of two peptides. However it did not exhibit substantial ion chelation, and we presumed that the observed radical scavenging potency of these peptides play a vital role for their strong antioxidant activity. Based on our results we suggest that hydrophobic amino acids present in peptide sequences contributed greatly for observed antioxidant activities.

  1. Partial characterization of an effluent produced by cooking of Jumbo squid (Dosidicus gigas) mantle muscle.

    PubMed

    Rosas-Romero, Zaidy G; Ramirez-Suarez, Juan C; Pacheco-Aguilar, Ramón; Lugo-Sánchez, Maria E; Carvallo-Ruiz, Gisela; García-Sánchez, Guillermina

    2010-01-01

    Jumbo squid (Dosidicus gigas) mantle muscle was cooked simulating industrial procedures (95 degrees C x 25 min, 1.2:5 muscle:water ratio). The effluent produced was analyzed for chemical and biochemical oxygen demands (COD and BOD(5), respectively), proximate analysis, flavor-related compounds (free amino acids, nucleotides and carbohydrates) and SDS-PAGE. The COD and BOD(5) exhibited variation among samplings (N=3) (27.4-118.5 g O(2)/L for COD and 11.3-26.7 g O(2)/L for BOD(5)). The effluent consisted of 1% total solids, 75% of which represented crude protein. Sixty percent of the total free amino acid content, which imparts flavor in squid species, corresponded to glutamic acid, serine, glycine, arginine, alanine, leucine and lysine. The nucleotide concentration followed this order, Hx>ADP>AMP>ATP>IMP>HxR. The variation observed in the present work was probably due to physiological maturity differences among the squid specimens (i.e., juvenile versus mature). Solids present in squid cooking effluent could be recovered and potentially used as flavor ingredients in squid-analog production by the food industry.

  2. Digestion of Ceramide 2-Aminoethylphosphonate, a Sphingolipid from the Jumbo Flying Squid Dosidicus gigas, in Mice.

    PubMed

    Tomonaga, Nami; Manabe, Yuki; Sugawara, Tatsuya

    2017-04-01

    Ceramide 2-aminoethylphosphonate (CAEP), a sphingophosphonolipid containing a carbon-phosphorus bond, is frequently found in marine organisms and has a unique triene type of sphingoid base in its structure. CAEP has not been evaluated as a food ingredient, although it is generally contained in Mollusca organisms such as squids and shellfish, which are consumed worldwide. In this study, we aimed to elucidate the effects of CAEP as a food component by evaluating the digestion of CAEP extracted from the skin of the jumbo flying squid Dosidicus gigas. Our results revealed that dietary CAEP was digested to free sphingoid bases via ceramides by the mouse small intestinal mucosa. At pH 7.2, CAEP was hydrolyzed more rapidly than the major mammalian sphingolipid sphingomyelin; however, the hydrolysis of CAEP was similar to that of sphingomyelin at pH 9.0. Thus, the digestion of CAEP may be catalyzed by alkaline spingomyelinase and other enzymes. Our findings provide important insights into the digestion of the dietary sphingophosphonolipid CAEP in marine foods.

  3. Purification and characterization of trimethylamine-N-oxide demethylase from jumbo squid (Dosidicus gigas).

    PubMed

    Fu, Xue-Yan; Xue, Chang-Hu; Miao, Ben-Chun; Liang, Jun-Ni; Li, Zhao-Jie; Cui, Feng-Xia

    2006-02-08

    Trimethylamine-N-oxide demethylase (TMAOase) was purified from Jumbo squid (Dosidicus gigas) and characterized in detail herein. The TMAOase was extracted from squid with 20 mM Tris-acetate buffer (pH 7.0) containing 1.0 M NaCl, followed by acid treatment and heat treatment. Then it was purified by deithylaminoethyl-cellulose and Sephacryl S-300 chromatography, subsequently resulting in an 839-fold purification. The molecular mass of the TMAOase was defined to be 17.5 kDa. The optimum pH of the purified TMAOase was 7.0, and its optimum temperature was confirmed to be 55 degrees C. The TMAOase was stable to heat treatment up to 50 degrees C and stable at pH 7.0-9.0. Reducing agents such as DTT, Na2SO3, and NADH were effective at activating TMAOase, and ethylenediaminetetraacetic acid, as well as Mg2+ and Ca2+, could also enhance the activity of TMAOase remarkably, whereas the TMAOase could be significantly inhibited by tea polyphenol, phytic acid and acetic acid. In addition, the TMAOase converted TMAO to dimethylamine and formaldehyde stoichiometrically with a K(m) of 26.2 mM.

  4. Onshore-offshore movement of jumbo squid (Dosidicus gigas) on the continental shelf

    NASA Astrophysics Data System (ADS)

    Stewart, Julia S.; Gilly, William F.; Field, John C.; Payne, John C.

    2013-10-01

    Jumbo squid (Dosidicus gigas) have greatly extended their range in the California Current System, where they forage on a variety of ecologically and economically important species that inhabit both coastal and offshore mesopelagic regions. Swimming abilities and behavior are important factors in assessing the impacts of this range expansion, particularly in regard to foraging in conjunction with onshore-offshore movement over the continental shelf. Here we describe a study of horizontal movements by jumbo squid along and across the continental shelf off Washington, USA, using acoustic tags in association with the Census of Marine Life's Pacific Ocean Shelf Tracking Program (POST) receiver arrays. We detected frequent movements along the shelf break, movement onto the shelf at night, and no evidence of movement as a cohesive school. Our results demonstrate feasibility of using acoustic tags and arrays to document horizontal movements of jumbo squid along and across the continental shelf. This is important in order to determine how those movements overlap with those of other ecologically and commercially important fish species.

  5. Characteristics of deacetylation and depolymerization of β-chitin from jumbo squid (Dosidicus gigas) pens.

    PubMed

    Jung, Jooyeoun; Zhao, Yanyun

    2011-09-27

    This study evaluated the deacetylation characteristics of β-chitin from jumbo squid (Dosidicus gigas) pens by using strongly alkaline solutions of NaOH or KOH. Taguchi design was employed to investigate the effect of reagent concentration, temperature, time, and treatment step on molecular mass (MM) and degree of deacetylation (DDA) of the chitosan obtained. The optimal treatment conditions for achieving high MM and DDA of chitosan were identified as: 40% NaOH at 90°C for 6h with three separate steps (2h+2h+2h) or 50% NaOH at 90°C for 6h with one step, or 50% KOH at 90°C for 4h with three steps (1h+1h+2h) or 6h with one step. The most important factor affecting DDA and MM was temperature and time, respectively. The chitosan obtained was then further depolymerized by cellulase or lysozyme with cellulase giving a higher degradation ratio, lower relative viscosity, and a larger amount of reducing-end formations than that of lysozyme due to its higher susceptibility. This study demonstrated that jumbo squid pens are a good source of materials to produce β-chitosan with high DDA and a wide range of MM for various potential applications.

  6. Trace element concentrations in the top predator jumbo squid (Dosidicus gigas) from the Gulf of California.

    PubMed

    Raimundo, Joana; Vale, Carlos; Rosa, Rui

    2014-04-01

    Jumbo (or Humboldt) squid, Dosidicus gigas, is a large jet-propelled top oceanic predator off the Eastern Pacific. The present study reports, for the first time, concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb in gills, mantle and digestive gland of this powerful pelagic squid in the Gulf of California. Zinc and Cu were the most abundant elements. All elements, with the exception of As, were largely stored in digestive gland; particularly Cd that reached concentrations between 57 and 509 µg g(-1). Significant relationships between tissues were found for Co (digestive gland-gills), As (gills-mantle) and Cd (digestive gland-mantle). Proportionality of Cd concentrations between mantle and digestive gland suggested that detoxification capacity by digestive gland was insufficient to avoid the transfer of this element to mantle and other tissues. Nonetheless, Cd concentrations in the mantle were always below the regulatory limit and, therefore lack of constraints for human consumption. On the basis of the fishery landings, one may estimate that up to 1t of Cd can be annually removed by jumbo squid fisheries.

  7. Salting-in effect on muscle protein extracted from giant squid (Dosidicus gigas).

    PubMed

    Zhang, Rui; Zhou, Ru; Pan, Weichun; Lin, Weiwei; Zhang, Xiuzhen; Li, Mengya; Li, Jianrong; Niu, Fuge; Li, Ang

    2017-01-15

    The salting-in effect on muscle protein is well-known in food science but hard to explain using conventional theories. Myofibrillar protein extracted from the giant squid (Dosidicus gigas) was selected as a model muscle protein to study this mechanism in KCl solutions. Changes in the secondary structures of myofibrillar protein molecules caused by concentrated salts, particularly in the paramyosin molecule conformation, have been reported. Zeta-potential determinations showed that these secondary structures have modified protein molecule surfaces. The zeta-potential of the myofibrillar protein molecules fell from -7.24±0.82 to -9.99±1.65mV with increasing salt concentration from 0.1 to 0.5M. The corresponding second virial coefficient increased from -85.43±3.8×10(-7) to -3.45±1.3×10(-7) molmLg(-2). The extended law of corresponding states suggests that reduced attractive interactions increase the protein solubility. Solubility measurements in alternating KCl concentrations showed that the conformational change was reversible.

  8. Extraction and Identification of the Pigment in the Adductor Muscle Scar of Pacific Oyster Crassostrea gigas.

    PubMed

    Hao, Shixin; Hou, Xin; Wei, Lei; Li, Jian; Li, Zhonghu; Wang, Xiaotong

    2015-01-01

    In this study, UV (ultraviolet) and IR (infrared radiation) spectral analysis were integrated to identify the pigment in the adductor muscle scar of the Pacific oyster Crassostrea gigas. The pigment was extracted from the adductor muscle scars of cleaned oyster shells that were pulverized, hydrolyzed in hot hydrochloric acid, purified with diethyl ether, and dissolved in 0.01 mL/L NaOH. The maximum absorption of the pigment in the UV absorption spectrum within the range of 190-500 nm was observed between 210-220 nm. The UV absorbance decreased with increasing wavelength which was consistent with the UV spectral absorption characteristics of melanin. In addition, Fourier transform infrared spectroscopy scanning revealed characteristic absorption peaks that emerged near 3440 cm-1 and 1630 cm-1, which was consistent with infrared scanning features of eumelanin (a type of melanin). This study has demonstrated for the first time that the pigment in the adductor muscle scar of the Pacific oyster is melanin, hinting that the adductor muscle could be another organ pigmenting the mollusc shell with melanin other than mantle.

  9. A study of diagnostic methods for Marteilioides chungmuensis infections in the Pacific oyster Crassostrea gigas.

    PubMed

    Choi, Hee Jung; Hwang, Jee Youn; Choi, Dong Lim; Huh, Min Do; Park, Myoung Ae

    2012-09-15

    The eggs of the Pacific oyster, Crassostraea gigas, become infertile when infected by the parasite Marteilioides chungmuensis. Histologically, M. chungmuensis infects the oyster oocyte cytoplasm, and the ovaries take on a "lumpy" appearance once infected, which lowers commercial value of the oyster. This has a negative economic impact on oyster farms in South Korea and Japan. In this study, we compared traditional diagnostic methods (histology) with two molecular-based methods (polymerase chain reaction [PCR] amplification and in situ hybridization [ISH]) to identify M. chungmuensis-infected oysters. The efficacy of PCR and ISH to identify M. chungmuensis-infected oysters was compared to that of routine histology in 100 oysters. Thirty infections were identified using PCR and 16 using histology, whereas 31 infections were identified using ISH. The ISH and PCR assays were more sensitive compared to using histology with standard epidemiological methods. We strongly recommend that early parasitic invasion should be monitored with PCR/ISH methodologies as a basis for developing effective diagnostic techniques to identify M. chungmuensis-infected oysters.

  10. The simple neuroendocrine-immune regulatory network in oyster Crassostrea gigas mediates complex functions.

    PubMed

    Liu, Zhaoqun; Wang, Lingling; Zhou, Zhi; Sun, Ying; Wang, Mengqiang; Wang, Hao; Hou, Zhanhui; Gao, Dahai; Gao, Qiang; Song, Linsheng

    2016-05-19

    The neuroendocrine-immune (NEI) regulatory network is a complex system, which plays an indispensable role in the immunity of the host. In the present study, the bioinformatical analysis of the transcriptomic data from oyster Crassostrea gigas and further biological validation revealed that oyster TNF (CgTNF-1 CGI_10018786) could activate the transcription factors NF-κB and HSF (heat shock transcription factor) through MAPK signaling pathway, and then regulate apoptosis, redox reaction, neuro-regulation and protein folding in oyster haemocytes. The activated immune cells then released neurotransmitters including acetylcholine, norepinephrine and [Met(5)]-enkephalin to regulate the immune response by arising the expression of three TNF (CGI_10005109, CGI_10005110 and CGI_10006440) and translocating two NF-κB (Cgp65, CGI_10018142 and CgRel, CGI_10021567) between the cytoplasm and nuclei of haemocytes. Neurotransmitters exhibited the immunomodulation effects by influencing apoptosis and phagocytosis of oyster haemocytes. Acetylcholine and norepinephrine could down-regulate the immune response, while [Met(5)]-enkephalin up-regulate the immune response. These results suggested that the simple neuroendocrine-immune regulatory network in oyster might be activated by oyster TNF and then regulate the immune response by virtue of neurotransmitters, cytokines and transcription factors.

  11. Response to selection for fast growth in the second generation of Pacific oyster ( Crassostrea gigas)

    NASA Astrophysics Data System (ADS)

    Wang, Qingzhi; Li, Qi; Kong, Lingfeng; Yu, Ruihai

    2012-09-01

    Mass selection for fast growth was conducted in three Pacific oyster ( Crassostrea gigas) stocks from China, Japan and Korea using previously established lines (CS1, JS1, and KS1). To determine whether continuous progress can be achieved by selection for growth, the progeny of three second-generation Pacific oyster lines was selected for shell height and evaluated via a 400-day farming experiment. When harvested at the end of the experiment, the selected crosses of CS2, JS2, and KS2 lines grew by 9.2%, 10.2% and 9.6% larger than the control crosses, respectively. During grow-out stage, the genetic gain of three selected lines was (10.2 ± 1.4)%, (10.4 ± 0.3)%, and (8.4 ± 1.6)%, respectively; and the corresponding realized heritability was 0.457 ± 0.143, 0.312 ± 0.071 and 0.332 ± 0.009, respectively. These results indicated that the selection for fast growth achieved steady progress in the second generation of oyster. Our work provides supportive evidence for the continuity of the Pacific oyster selective breeding program.

  12. Pathogenicity testing of shellfish hatchery bacterial isolates on Pacific oyster Crassostrea gigas larvae.

    PubMed

    Estes, Robyn M; Friedman, Carolyn S; Elston, Ralph A; Herwig, Russell P

    2004-03-10

    Bacterial diseases are a major cause of larval mortality in shellfish hatcheries. Even with proper sanitation measures, bacterial pathogens cannot be eliminated in all cases. The pathogenicity of bacteria isolated from Pacific Northwest shellfish hatcheries to Pacific oyster Crassostrea gigas larvae was investigated. We found 3 highly pathogenic strains and 1 mildly pathogenic strain among 33 isolates tested. These strains appear to be members of the genus Vibrio. Although there have been many studies of bivalve bacterial pathogens, a standard method to assess bacterial pathogenicity in bivalve larvae is needed. Thus, we developed 2 methods using either 15 ml conical tubes or tissue culture plates that were employed for rapidly screening bacterial strains for pathogenicity to Pacific oyster larvae. The tissue culture plates worked well for screening both mildly pathogenic strains and LD50 (lethal dose) assays. This method allowed for non-intrusive and non-destructive observation of the oyster larvae with a dissecting microscope. The LD50 for the 3 highly pathogenic strains ranged between 1.6 and 3.6 x 10(4) colony forming units (CFU) ml(-1) after 24 h and between 3.2 x 102 and 1.9 x 10(3) CFU ml(-1) after 48 h.

  13. Screening and selection of stress resistant Lactobacillus spp. isolated from the marine oyster (Crassostrea gigas).

    PubMed

    Lee, Hae-In; Kim, Min Hee; Kim, Kwan Young; So, Jae-Seong

    2010-10-01

    We attempted to isolate Lactobacillus spp. from the marine oyster (Crassostrea gigas) and select stress resistant strains for development of a future marine aquaculture feed adjuvant. A total of 83 lactobacilli strains were isolated from oyster. They were all Gram-positive, rod-shaped and catalase-negative. By performing a stress resistance assay, we selected eighteen isolates. Based on 16S rRNA gene sequencing, Lactobacillus paracasei was the most prevalent species among the selected isolates. The in vitro antagonistic effect of the selected strains against fish pathogens was assayed by measurement of inhibition diameters. Except for MH44, MH51, MH53 and MH62, most of the isolates showed inhibition of Vibrio alginolyticus and Vibrio proteolyticus (diameters over 15 mm). Lactobacillus rhamnosus MH22 was selected as the most stress resistant strain showing the MICs of 1.8 M NaCl, 14% ethanol and 0.014% hydrogen peroxide. L. rhamnosus MH22 isolated from oyster has a potential to be applied as a microbial feed adjuvant for marine aquaculture.

  14. Metals concentrations in sediments and oyster Crassostrea gigas from La Pitahaya lagoon, Sinaloa, NW Mexico

    NASA Astrophysics Data System (ADS)

    Luna Varela, R.; Muñoz Sevilla, N.; Campos Villegas, L.; Rodriguez Espinosa, P.; Gongora Gomez, A.; MP, J.

    2013-05-01

    This present study was performed in a culture of Crassostrea gigas in La Pitahaya, Sinaloa, México. The main objective is to identify the enrichment pattern of trace elements (Cu, Cd, Cr, Ni, Pb, Zn, Hg, As, V) also was determine concentrations thereof in oyster. Four sampling sites were selected, two smaller channels which connect the lagoon directly , the region of culture and connection with the sea ; and each sampling consisted of 4 sample sediments and 50 oysters of commercial size per mounth . Concentrations of trace metals were determined using atomic absorption spectrophotometry (AAS). The higher concentration of elements in certain samples clearly suggests that they are directly fed by the smaller channels which connect the lagoon directly. These small channels often carry the contaminants which are absorbed and deposited in the sediments. The results were also compared with the Effect Range Low (ERL) and Effect Range Medium (ERM) of NOAA and it indicates that Ni is above the ERL values. Cadmium, lead, chrome and copper concentrations exceeded the limits permissible of bivalbe mollusks established by the sanitary regulations

  15. Preferential bivalent formation in tetraploid male of pacific oyster Crassostrea gigas Thunberg

    NASA Astrophysics Data System (ADS)

    Zhang, Zhengrui; Wang, Xinglian; Zhang, Quanqi; Allen, Standish

    2013-11-01

    Artificially induced tetraploid Pacific oyster, Crassostrea gigas Thunberg, produces more aneuploid gametes than normal diploid one, although they showed a comparable fecundity to diploidy. The meiotic chromosome configuration of 3 tetraploid and 1 tetraploid/triploid mosaic males were analyzed through direct chromosome observation. A majority of metaphase I spermatocytes contained both bivalents and quadrivalents. The chromosome configuration of these males was characterized by preferential formation of bivalents to quadrivalents. Bivalents appeared in all spermatocytes and consisted of 86% of all chromosome aggregates. In comparison, quadrivalents occurred in 91% spermatocytes and consisted of only 12.6% of all chromosome aggregates. The mean bivalent frequency per spermatocyte varied between 14.4 and 17.2; while that of quadrivalents varied between 2.2 and 2.7. Most quadrivalents were tandemly chained (58%) or circled (39%). The total number of chromosome aggregates per spermatocyte ranged from 13 to 20 with an average of 17.6; while 18 (16 bivalents and 2 quadrivalents) was the most frequent. Univalents and trivalents appeared in very low frequency. Aneuploid (hypotetraploid) spermatocytes were observed in a low frequency. The chromosome configuration of in the mosaic individual was similar to that of tetraploid individuals. The percentage of triploid spermatocytes (2%) of the mosaic individual was significantly lower (χ2 =30, P < 0.01) than that of triploid cells (46%) in its somatic tissue.

  16. The neuroendocrine immunomodulatory axis-like pathway mediated by circulating haemocytes in pacific oyster Crassostrea gigas

    PubMed Central

    Liu, Zhaoqun; Zhou, Zhi; Jiang, Qiufen; Yi, Qilin; Qiu, Limei; Song, Linsheng

    2017-01-01

    The neuroendocrine-immune (NEI) regulatory network is a complex system, which plays an indispensable role in the immunity of host. In this study, a neuroendocrine immunomodulatory axis (NIA)-like pathway mediated by the nervous system and haemocytes was characterized in the oyster Crassostrea gigas. Once invaded pathogen was recognized by the host, the nervous system would temporally release neurotransmitters to modulate the immune response. Instead of acting passively, oyster haemocytes were able to mediate neuronal immunomodulation promptly by controlling the expression of specific neurotransmitter receptors on cell surface and modulating their binding sensitivities, thus regulating intracellular concentration of Ca2+. This neural immunomodulation mediated by the nervous system and haemocytes could influence cellular immunity in oyster by affecting mRNA expression level of TNF genes, and humoral immunity by affecting the activities of key immune-related enzymes. In summary, though simple in structure, the ‘nervous-haemocyte’ NIA-like pathway regulates both cellular and humoral immunity in oyster, meaning a world to the effective immune regulation of the NEI network. PMID:28077596

  17. Effects of subchronic exposure to glyphosate in juvenile oysters (Crassostrea gigas): From molecular to individual levels.

    PubMed

    Mottier, Antoine; Séguin, Alexis; Devos, Alexandre; Pabic, Charles Le; Voiseux, Claire; Lebel, Jean Marc; Serpentini, Antoine; Fievet, Bruno; Costil, Katherine

    2015-06-30

    Glyphosate-based herbicides are extensively used and can be measured in aquatic ecosystems, including coastal waters. The effect of glyphosate on non-target organisms is an issue of worldwide concern. The aim of this study was to investigate the effects of subchronic exposure to glyphosate in juvenile oysters, Crassostrea gigas. Yearling oysters were exposed to three concentrations of glyphosate (0.1, 1 and 100μgL(-1)) for 56days. Various endpoints were studied, from the individual level (e.g., gametogenesis and tissue alterations) to the molecular level (mRNA quantification), including biochemical endpoints such as glutathione-S-transferase (GST) and catalase activities and malondialdehyde content. No mortality and growth occurred during the experiment, and individual biomarkers revealed only slight effects. The levels of gene expression significantly increased in oysters exposed to the highest glyphosate concentration (GST and metallothioneins) or to all concentrations (multi-xenobiotic resistance). These results suggested an activation of defence mechanisms at the molecular level.

  18. Gill erosion and herpesvirus in Crassostrea gigas cultured in Baja California, Mexico.

    PubMed

    Vásquez-Yeomans, Rebeca; García-Ortega, Mauricio; Cáceres-Martínez, Jorge

    2010-03-09

    Recurrent episodes of mortality of Crassostrea gigas cultured in northwestern Mexico have been occurring since 1997. Previous studies on bacteria, protozoans, and metazoans as presumptive causal agents have been inconclusive. However, erosions in the marginal indentation of gills have been frequently observed in oysters from areas affected by mortality events, and in 2000 those lesions were associated with the detection of a herpes-like virus. The present study aimed to describe the histological alterations of eroded gills and to determine whether ostreid herpesvirus 1 (OsHV-1) or a related virus was associated with them using in situ hybridization (ISH). Histology showed that gill filaments were fused. In severe cases, deformation of the interlamellar junctions, swelling, and the loss of water channels was observed. ISH analysis revealed the presence of OsHV-1 DNA or a related virus in cells of the gills. Some labeled cells were large with dark granules inside their cytoplasm. These cells were surrounded by infiltrating hemocytes. Some cells interpreted as hemocytes were labeled and observed in eroded and non-eroded areas of the gill. Large cells detected by ISH were also observed by conventional histology with hematoxylin-eosin staining. Whether the virus produces the erosions in the gills, or the erosions in the gills are produced by an unknown condition and favor the presence of the virus, remains unresolved. It is also not clear whether the lesions contribute to mortality.

  19. Heavy metal toxicity in Exosphaeroma gigas (Crustacea, Isopoda) from the coastal zone of Beagle Channel.

    PubMed

    Giarratano, Erica; Comoglio, Laura; Amin, Oscar

    2007-11-01

    Acute toxicity of copper, cadmium, and zinc on isopod Exosphaeroma gigas was evaluated at 20 per thousand and 30 per thousand salinity. Six concentrations were assayed to estimate effective concentration of the toxicant that affects 50% of tested animal (EC50), while physiological responses and bioaccumulation were determined at 0.42 and 1.95 mg L(-1) of each metal. The following toxicity orders were obtained: Cd>or=Cu>Zn at 20 per thousand salinity and Cu>Zn>or=Cd at 30 per thousand salinity. Copper treatments showed a reduction in oxygen consumption at 30 per thousand salinity, while an opposite trend was observed at 20 per thousand salinity. Zinc caused dissimilar effects, while in cadmium significant reduction was only registered in 0.42(20 per thousand) mg L(-1). Ammonia excretion was generally higher in treatments than control at 20 per thousand salinity. At 30 per thousand salinity, excretion did not change in relation to control or diminished. In general terms, O:N atomic ratios indicated a preponderant protein metabolism. Bioaccumulation of assayed metals was higher at lowest salinity and increased with increasing toxic concentrations.

  20. Characterisation of the NA62 GigaTracker end of column readout ASIC

    NASA Astrophysics Data System (ADS)

    Noy, M.; Aglieri Rinella, G.; Fiorini, M.; Jarron, P.; Kaplon, J.; Kluge, A.; Martin, E.; Morel, M.; Perktold, L.; Riedler, P.

    2011-01-01

    The architecture and characterisation of the End Of Column demonstrator readout ASIC for the NA62 GigaTracker hybrid pixel detector is presented. This ASIC serves as a proof of principle for a pixel chip with 1800 pixels which must perform time stamping to better than 200 ps (RMS), provide 300 μm pitch position information and operate with a dead-time of 1% or less for 800 MHz-1 GHz beam rate. The demonstrator ASIC comprises a full test column with 45 pixels alongside other test structures. The timewalk correction mechanism employed is measurement of the time-over-threshold, coupled with an off-detector look-up table. The time to digital converter is a delay locked loop with 32 contributing delay cells fed with a 320 MHz to yield a nominal bin size of 97 ps. Recently, P-in-N sensors have been bump-bonded to the ASIC and characterisation of these assemblies has begun.

  1. A water-vapour giga-maser in the active galaxy TXFS2226-184.

    PubMed

    Koekemoer, A M; Henkel, C; Greenhill, L J; Dey, A; van Breugel, W; Codella, C; Antonucci, R

    1995-12-14

    Active galactic nuclei are thought to be powered by gas falling into a massive black hole; the different types of active galaxy may arise because we view them through a thick torus of molecular gas at varying angles of inclination. One way to determine whether the black hole is surrounded by a torus, which would obscure the accretion disk around the black hole along certain lines of sight, is to search for water masers, as these exist only in regions with plentiful molecular gas. Since the first detection of an extra-galactic water maser in 1979, they have come to be associated primarily with active galaxies, and have even been used to probe the mass of the central engine. Here we report the detection of a water giga-maser in the radio galaxy TXFS2226-184. The strength of the emission supports a recently proposed theory of maser pumping that allows for even more powerful masers, which might be detectable at cosmological distances. Water masers may accordingly provide a way to determine distances to galaxies outside the usual distance ladder, providing an independent calibration of the Hubble constant.

  2. Antimicrobial histones and DNA traps in invertebrate immunity: evidences in Crassostrea gigas.

    PubMed

    Poirier, Aurore C; Schmitt, Paulina; Rosa, Rafael D; Vanhove, Audrey S; Kieffer-Jaquinod, Sylvie; Rubio, Tristan P; Charrière, Guillaume M; Destoumieux-Garzón, Delphine

    2014-09-05

    Although antimicrobial histones have been isolated from multiple metazoan species, their role in host defense has long remained unanswered. We found here that the hemocytes of the oyster Crassostrea gigas release antimicrobial H1-like and H5-like histones in response to tissue damage and infection. These antimicrobial histones were shown to be associated with extracellular DNA networks released by hemocytes, the circulating immune cells of invertebrates, in response to immune challenge. The hemocyte-released DNA was found to surround and entangle vibrios. This defense mechanism is reminiscent of the neutrophil extracellular traps (ETs) recently described in vertebrates. Importantly, oyster ETs were evidenced in vivo in hemocyte-infiltrated interstitial tissues surrounding wounds, whereas they were absent from tissues of unchallenged oysters. Consistently, antimicrobial histones were found to accumulate in oyster tissues following injury or infection with vibrios. Finally, oyster ET formation was highly dependent on the production of reactive oxygen species by hemocytes. This shows that ET formation relies on common cellular and molecular mechanisms from vertebrates to invertebrates. Altogether, our data reveal that ET formation is a defense mechanism triggered by infection and tissue damage, which is shared by relatively distant species suggesting either evolutionary conservation or convergent evolution within Bilateria.

  3. Comparative Transcriptome Analysis of the Pacific Oyster Crassostrea gigas Characterized by Shell Colors: Identification of Genetic Bases Potentially Involved in Pigmentation

    PubMed Central

    Feng, Dandan; Li, Qi; Yu, Hong; Zhao, Xuelin; Kong, Lingfeng

    2015-01-01

    Background Shell color polymorphisms of Mollusca have contributed to development of evolutionary biology and population genetics, while the genetic bases and molecular mechanisms underlying shell pigmentation are poorly understood. The Pacific oyster (Crassostrea gigas) is one of the most important farmed oysters worldwide. Through successive family selection, four shell color variants (white, golden, black and partially pigmented) of C. gigas have been developed. To elucidate the genetic mechanisms of shell coloration in C. gigas and facilitate the selection of elite oyster lines with desired coloration patterns, differentially expressed genes (DEGs) were identified among the four shell color variants by RNA-seq. Results Digital gene expression generated over fifteen million reads per sample, producing expression data for 28,027 genes. A total number of 2,645 DEGs were identified from pair-wise comparisons, of which 432, 91, 43 and 39 genes specially were up-regulated in white, black, golden and partially pigmented shell of C. gigas, respectively. Three genes of Abca1, Abca3 and Abcb1 which belong to the ATP-binding cassette (ABC) transporters super-families were significantly associated with white shell formation. A tyrosinase transcript (CGI_10008737) represented consistent up-regulated pattern with golden coloration. We proposed that white shell variant of C. gigas could employ “endocytosis” to down-regulate notch level and to prevent shell pigmentation. Conclusion This study discovered some potential shell coloration genes and related molecular mechanisms by the RNA-seq, which would provide foundational information to further study on shell coloration and assist in selective breeding in C. gigas. PMID:26693729

  4. Commercially-cultured oysters (Crassostrea gigas) exert top-down control on intertidal pelagic resources in Willapa Bay, Washington, USA

    NASA Astrophysics Data System (ADS)

    Wheat, Elizabeth; Ruesink, Jennifer L.

    2013-08-01

    The capacity of filter feeders to reduce seston and phytoplankton concentrations in the water column has important implications for restoration and management of coastal ecosystems. We directly measured changes in chlorophyll a concentration on commercially stocked intertidal oyster beds (Crassostrea gigas) in Willapa Bay, Washington, USA by recording water properties near small drifters as they tracked parcels of water across tide flats. Chlorophyll declined 9.6% per half hour in water passing on-bottom adult oysters and 41% for longline adult oysters, whereas chlorophyll concentrations increased as water flowed across tide flats without adult oysters. Field filtration rates, which were fit to exponential declines in chlorophyll and accounted for oyster density and water depth, averaged 0.35 L g- 1 h- 1 (shucked dry weight) for on-bottom aquaculture and 0.73 L g- 1 h- 1 for longline culture, compared to values of 2.5-12 L g- 1 h- 1 reported from laboratory studies of C. gigas. Field filtration rates may be lower than laboratory rates due to unfavorable field conditions (e.g., low initial chlorophyll concentrations) or masked by resuspension of benthic microalgae. In addition to distinctions among on-bottom, longline, and no-oyster habitats, Akaike's Information Criterion analysis showed temperature, initial chlorophyll concentration, and depth related to chlorophyll decline. This research corroborates mathematical models suggesting that benthic suspension feeders are exerting top-down control of pelagic production in this estuary, with strong patterns in chlorophyll emerging across extensive tideflats populated by C. gigas despite low field filtration rates.

  5. Use of nanoindentation technique for a better understanding of the fracture toughness of Strombus gigas conch shell

    SciTech Connect

    Romana, L.; Thomas, P.; Bilas, P.; Mansot, J.L.; Merrifiels, M.; Bercion, Y.; Aranda, D. Aldana

    2013-02-15

    In this work the nanochemical properties of the composite organomineral biomaterial constituting Strombus gigas conch shell are studied by means of dynamic mechanical analyses associated to nanoidentation technique. The measurements are performed on shell samples presenting different surface orientations relative to the growth axis of the conch shell. The influence of the organic component of the biomaterial on its nanomechanical properties is also investigated by studying fresh and dried S. gigas conch shells. Monocrystalline aragonite is used as a reference. For the understanding of nanochemical behaviour, special attention is paid to the pop in events observed on the load/displacement curves which results from nanofractures' initiation and propagation occuring during the load process. In order to better understand the mechanical properties systematic studies of the structure and morphology are performed using scanning electron microscopy, atomic force microscopy and X-ray diffractometry. The hardness and Young's modulus values measured on bio aragonite samples are close to those of the aragonite mineral standard. This surprising result shows that, H and E values are not related to the bio composition and lamellar structure of the bio aragonite. However, it was found that the organic layer and the micro architecture strongly influence the nanofracture initiation and propagation processes in the samples. Statistic study of the pop-in events can help to predict the macroscopic mechanical behaviour of the material. - Highlights: ► Nanomechanical properties of Strombus gigas conch shell ► Low influence of the crossed lamellar structure on H and E values at the nano scale ► Strong influence of the crossed lamellar on nanocracks initiation ► Correlation between mechanical behaviors at the macro and nano scales.

  6. Locomotion and behavior of Humboldt squid, Dosidicus gigas, in relation to natural hypoxia in the Gulf of California, Mexico.

    PubMed

    Gilly, William F; Zeidberg, Louis D; Booth, J Ashley T; Stewart, Julia S; Marshall, Greg; Abernathy, Kyler; Bell, Lauren E

    2012-09-15

    We studied the locomotion and behavior of Dosidicus gigas using pop-up archival transmitting (PAT) tags to record environmental parameters (depth, temperature and light) and an animal-borne video package (AVP) to log these parameters plus acceleration along three axes and record forward-directed video under natural lighting. A basic cycle of locomotor behavior in D. gigas involves an active climb of a few meters followed by a passive (with respect to jetting) downward glide carried out in a fins-first direction. Temporal summation of such climb-and-glide events underlies a rich assortment of vertical movements that can reach vertical velocities of 3 m s(-1). In contrast to such rapid movements, D. gigas spends more than 80% of total time gliding at a vertical velocity of essentially zero (53% at 0±0.05 m s(-1)) or sinking very slowly (28% at -0.05 to -0.15 m s(-1)). The vertical distribution of squid was compared with physical features of the local water column (temperature, oxygen and light). Oxygen concentrations of ≤20 μmol kg(-1), characteristic of the midwater oxygen minimum zone (OMZ), can influence the daytime depth of squid, but this depends on location and season, and squid can 'decouple' from this environmental feature. Light is also an important factor in determining daytime depth, and temperature can limit nighttime depth. Vertical velocities were compared over specific depth ranges characterized by large differences in dissolved oxygen. Velocities were generally reduced under OMZ conditions, with faster jetting being most strongly affected. These data are discussed in terms of increased efficiency of climb-and-glide swimming and the potential for foraging at hypoxic depths.

  7. Oxidation of Alumina-Forming MAX Phases in Turbine Environments

    NASA Technical Reports Server (NTRS)

    Smialek, James; Garg, Anita; Harder, Bryan; Nesbitt, James; Gabb, Timothy; Gray, SImon

    2017-01-01

    Protective coatings for high temperature turbine components are based on YSZ thermal barriers and oxidation resistant, alumina-forming NiAl or NiCoCrAlY bond coats. Ti2AlC and Cr2AlC MAX phases are thus of special interest because of good oxidation resistance and CTE that can match Al2O3 and YSZ. Their alumina scales grow according to cubic kinetics due to grain growth in the scale, with initial heating dominated by fast TiO2 growth. Protective cubic kinetics are also found in high pressure burner rig tests of MAXthal 211 Ti2AlC, but with reduced rates due to volatile TiO(OH)2 formation in water vapor. YSZ-coatings on bulk Ti2AlC exhibit remarkable durability up to 1300C in furnace tests and at least a 25x life advantage compared to superalloys. At another extreme, Cr2AlC is resistant to low temperature Na2SO4 hot corrosion and exhibits thermal cycling stability bonded to a superalloy disk material. Accordingly, sputtered Cr2AlC coatings on disk specimens prevented hot corrosion detriments on LCF. Breakaway oxidation (Ti2AlC), scale spallation (Cr2AlC), interdiffusion, and processing as coatings still present serious challenges. However the basic properties of MAX phases provide some unusual opportunities for use in high temperature turbines.

  8. Acetyl-L-Carnitine as an Adjunctive Therapy in the Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Placebo-Controlled Trial

    ERIC Educational Resources Information Center

    Abbasi, Seyed-Hesameddin; Heidari, Shahram; Mohammadi, Mohammad-Reza; Tabrizi, Mina; Ghaleiha, Ali; Akhondzadeh, Shahin

    2011-01-01

    The objective of this study was to test whether a previous observed Acetyl-L-carnitine (ALC) treatment effect could be repeated in an ALC adjunctive therapy treatment trial of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. This was a six-week, randomized clinical trial undertaken in an outpatient child and adolescent…

  9. The neurobiology of acetyl-L-carnitine.

    PubMed

    Traina, Giovanna

    2016-06-01

    A large body of evidence points to the positive effects of dietary supplementation of acetyl-L-carnitine (ALC). Its use has shown health benefits in neuroinflammation, which is a common denominator in a host of neurodegenerative diseases. ALC is the principal acetyl ester of L-Carnitine (LC), and it plays an essential role in intermediary metabolism, acting as a donor of acetyl groups and facilitating the transfer of fatty acids from cytosol to mitochondria during beta-oxidation. Dietary supplementation of ALC exerts neuroprotective, neurotrophic, antidepressive and analgesic effects in painful neuropathies. ALC also has antioxidant and anti-apoptotic activity. Moreover, ALC exhibits positive effects on mitochondrial metabolism, and shows promise in the treatment of aging and neurodegenerative pathologies by slowing the progression of mental deterioration. In addition, ALC plays neuromodulatory effects on both synaptic morphology and synaptic transmission. These effects are likely due to affects of ALC through modulation of gene expression on several targets in the central nervous system. Here, we review the current state of knowledge on effects of ALC in the nervous system.

  10. Transcription and protein synthesis inhibitors influence long-term effects of acetyl-l-carnitine on non-associative learning in the leech.

    PubMed

    Traina, Giovanna; Scuri, Rossana

    2015-01-01

    Acetyl-l-carnitine (ALC) is the principal acetyl ester of L-carnitine and it plays an essential role in intermediary metabolism. ALC affects several targets in the nervous system. Along this line of investigation, we analyzed the long-term effects of ALC on elementary nonassociative learning in the swimming induction model of the leech Hirudo medicinalis, in which nociceptive stimulation of the dorsal skin produces a more rapid swim response to a test stimulus (sensitization). In this simplified model a single ALC administration blocked the sensitizing effects of nociceptive stimulation in swim induction showing increasingly long lasting effects. Herein, we have analyzed the long-term effects of ALC on sensitization and dishabituation. Leeches were treated with inhibitors of either transcription or protein synthesis 30 min after the administration of ALC and, subsequently, subjected to noxious stimuli: the animals exhibited a sensitized swimming response 6 days after ALC treatment but not after 2 hours indicating that the long-term suppressive effects of ALC on sensitization/dishabituation needed mRNA and protein synthesis.

  11. Aminoclay-lipid hybrid composite as a novel drug carrier of fenofibrate for the enhancement of drug release and oral absorption.

    PubMed

    Yang, Liang; Shao, Yating; Han, Hyo-Kyung

    2016-01-01

    This study aimed to prepare the aminoclay-lipid hybrid composite to enhance the drug release and improve the oral bioavailability of poorly water-soluble fenofibrate. Antisolvent precipitation coupled with an immediate freeze-drying method was adopted to incorporate fenofibrate into aminoclay-lipid hybrid composite (ALC). The optimal composition of the ALC formulation was determined as the ratios of aminoclay to krill oil of 3:1 (w/w), krill oil to fenofibrate of 2:1 (w/w), and antisolvent to solvent of 6:4 (v/v). The morphological characteristics of ALC formulation were determined using scanning electron microscopy, differential scanning calorimetry, and X-ray powder diffraction, which indicated microcrystalline state of fenofibrate in ALC formulation. The ALC formulation achieved almost complete dissolution within 30 minutes, whereas the untreated powder and physical mixture exhibited less than 15% drug release. Furthermore, ALC formulation effectively increased the peak plasma concentration (C max) and area under the curve (AUC) of fenofibric acid (an active metabolite) in rats by approximately 13- and seven-fold, respectively. Furthermore, ALC formulation exhibited much lower moisture sorption behavior than the lyophilized formulation using sucrose as a cryoprotectant. Taken together, the present findings suggest that ALC formulation is promising for improving the oral absorption of poorly soluble fenofibrate.

  12. Prognostic value of lymphocyte/monocyte ratio in advanced Hodgkin lymphoma: correlation with International Prognostic Score and tumor associated macrophages.

    PubMed

    Jakovic, Ljubomir R; Mihaljevic, Biljana S; Andjelic, Bosko M; Bogdanovic, Andrija D; Perunicic Jovanovic, Maja D; Babic, Dragan D; Bumbasirevic, Vladimir Z

    2016-08-01

    We studied the prognostic significance of the absolute lymphocyte/monocyte count ratio (ALC/AMC), its contribution to the prognostic value of the International Prognostic Score (IPS), and evaluated if ALC/AMC could serve as a proxy for the frequency of CD68 + tumor-associated macrophages (TAMs) in 101 patients with advanced Hodgkin lymphoma (HL). The receiver operating characteristic (ROC) curve identified best cut-off values of 2.0 for ALC/AMC and 25% for CD68 + TAM. Patients with ALC/AMC < 2, IPS > 2 and > 25% CD68 + TAM had an inferior overall survival (OS) and event-free survival (EFS). Spearman's test also uncovered a significant correlation between the ALC/AMC and TAM. Multivariate analysis identified ALC/AMC < 2, IPS > 2 and > 25% CD68 + TAM as poor prognostic factors of OS and EFS. After evaluating ALC/AMC and IPS, we stratified patients into three progressively-worse-outcome groups (low-risk: 0 risk factors; intermediate: 1 risk factor; high: 2 risk factors). Our study encourages the combination of ALC/AMC with IPS, for refining risk prediction in advanced HL patients.

  13. Motivation, Test Results, Gender Differences, and Foreign Languages: How Do They Connect?

    ERIC Educational Resources Information Center

    Zammit, Susan A.

    The testing of 32,000 students in Australia and New Zealand participating in The Australian Language Certificates (ALC) provided the opportunity to examine students' attitude and learning preferences when studying a language other than English. The ALC offered the opportunity to learn seven languages in a Languages Other Than English (LOTE)…

  14. Seroprevalence, isolation, first genetic characterization of Toxoplasma gondii, and possible congenital transmission in wild moose from Minnesota, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toxoplasma gondii infections are widespread in white tailed deer (Odocoileus virginianus) but little is known of its prevalence in other cervids in the USA. Moose (Alces alces) is a popular large game animal, hunted for its meat and trophy antlers. Here, we report seroprevalence, isolation and genet...

  15. Association analysis of PRNP gene region with chronic wasting disease in Rocky Mountain elk

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of cervids including whitetail (Odocoileus virginianus) and mule deer (Odocoileus hemionus), Rocky Mountain elk (Cervus elaphus nelsoni), and moose (Alces alces). A leucine variant at position 132 (132L) in...

  16. Aminoclay–lipid hybrid composite as a novel drug carrier of fenofibrate for the enhancement of drug release and oral absorption

    PubMed Central

    Yang, Liang; Shao, Yating; Han, Hyo-Kyung

    2016-01-01

    This study aimed to prepare the aminoclay–lipid hybrid composite to enhance the drug release and improve the oral bioavailability of poorly water-soluble fenofibrate. Antisolvent precipitation coupled with an immediate freeze-drying method was adopted to incorporate fenofibrate into aminoclay–lipid hybrid composite (ALC). The optimal composition of the ALC formulation was determined as the ratios of aminoclay to krill oil of 3:1 (w/w), krill oil to fenofibrate of 2:1 (w/w), and antisolvent to solvent of 6:4 (v/v). The morphological characteristics of ALC formulation were determined using scanning electron microscopy, differential scanning calorimetry, and X-ray powder diffraction, which indicated microcrystalline state of fenofibrate in ALC formulation. The ALC formulation achieved almost complete dissolution within 30 minutes, whereas the untreated powder and physical mixture exhibited less than 15% drug release. Furthermore, ALC formulation effectively increased the peak plasma concentration (Cmax) and area under the curve (AUC) of fenofibric acid (an active metabolite) in rats by approximately 13- and seven-fold, respectively. Furthermore, ALC formulation exhibited much lower moisture sorption behavior than the lyophilized formulation using sucrose as a cryoprotectant. Taken together, the present findings suggest that ALC formulation is promising for improving the oral absorption of poorly soluble fenofibrate. PMID:27042061

  17. Sense of Belonging and First-Year Academic Literacy

    ERIC Educational Resources Information Center

    Marshall, Steve; Zhou, Mingming; Gervan, Ted; Wiebe, Sunita

    2012-01-01

    In this article, we analyze a broad range of factors that affect the sense of belonging of undergraduate students taking a first-year academic literacy course (ALC) at a multicultural, multilingual university in Vancouver, Canada. Students who fail to meet the university's language and literacy requirements are required to pass ALC before they can…

  18. Exploring Dimensions of Social Inclusion among Alternative Learning Centres in the USA

    ERIC Educational Resources Information Center

    Henderson, Dawn X.; Barnes, Rachelle Redmond

    2016-01-01

    Increasing disparities in out-of-school suspension and dropout rates have led a number of school districts to develop alternative models of education to include alternative learning centres (ALCs). Using an exploratory mixed methods design, this study explores dimensions of social inclusion among ALCs, located in the southeastern region of the…

  19. Regulation of Hox orthologues in the oyster Crassostrea gigas evidences a functional role for promoter DNA methylation in an invertebrate.

    PubMed

    Saint-Carlier, Emma; Riviere, Guillaume

    2015-06-04

    DNA methylation within promoter regions (PRDM) controls vertebrate early gene transcription and thereby development, but is neglected outside this group. However, epigenetic features in the oyster Crassostrea gigas suggest functional significance of PDRM in invertebrates. To investigate this, reporter constructs containing in vitro methylated oyster Hox gene promoters were transfected into oyster embryos. The influence of in vivo methylation was studied using bisulfite sequencing and DNA methyltransferase inhibition during development. Our results demonstrate that methylation controls the transcriptional activity of the promoters investigated, unraveling a functional role for PRDM in a lophotrochozoan, an important finding regarding the evolution of epigenetic regulation.

  20. Inheritance of 15 microsatellites in the Pacific oyster Crassostrea gigas: segregation and null allele identification for linkage analysis

    NASA Astrophysics Data System (ADS)

    Li, Li; Guo, Ximing; Zhang, Guofan

    2009-02-01

    Microsatellites were screened in a backcross family of the Pacific oyster, Crassostrea gigas. Fifteen microsatellite loci were distinguishable and polymorphic with 6 types of allele-combinations. Null alleles were detected in 46.7% of loci, accounting for 11.7% of the total alleles. Four loci did not segregate in Mendelian Ratios. Three linkage groups were identified among 7 of the 15 segregating loci. Fluorescence-based automated capillary electrophoresis (ABI 310 Genetic Analyzer) that used to detect the microsatellite loci, has been proved a fast, precise, and reliable method in microsatellite genotyping.

  1. A cytokine-like factor astakine accelerates the hemocyte production in Pacific oyster Crassostrea gigas.

    PubMed

    Li, Yiqun; Jiang, Shuai; Li, Meijia; Xin, Lusheng; Wang, Lingling; Wang, Hao; Qiu, Limei; Song, Linsheng

    2016-02-01

    Astakine has been reported to be a hematopoietic growth factor of prokineticin homolog firstly found in arthropods freshwater crayfish Pacifastacus leniusculus. In the present study, an astakine homologous gene was identified from Pacific oyster Crassostrea gigas (designated CgAstakine). The full length cDNA of CgAstakine encoded a polypeptide of 103 amino acids containing a prokineticin (PK) domain homologous to that in astakine from freshwater crayfish P. leniusculus. The deduced amino acid sequence of CgAstakine shared higher similarity with those of other invertebrate astakines than prokineticins from vertebrates. The mRNA of CgAstakine was highly expressed in hepatopancreas and adductor muscle of oyster, while the CgAstakine protein was mainly distributed in hepatopancreas, gill and hemocytes. The mRNA expression of CgAstakine in hemocytes was significantly increased (p < 0.01) and maintained at a high level from 3 h to 9 h after Vibrio anguillarum challenge. After the oyster hemocytes were incubated with 5 μg/mL recombinant CgAstakine protein (rCgAstakine) for 24 h in vitro, the proliferation of hemocytes was significantly increased to 1.89 fold of that in control group (p < 0.05). Moreover, the total count of oyster hemocytes was significantly upregulated (2.45 fold of that in control group, p < 0.05) at 12 h after the oysters were received an injection of rCgAstakine (0.5 μg/g). These results collectively indicated that CgAstakine could modulate the hemocytes proliferation both in vitro and in vivo, and probably involved in the hematopoietic process fighting against the invasion of foreign pathogens.

  2. Metals and trace elements in giant garter snakes (Thamnophis gigas) from the Sacramento Valley, California, USA

    USGS Publications Warehouse

    Wylie, G.D.; Hothem, R.L.; Bergen, D.R.; Martin, L.L.; Taylor, R.J.; Brussee, B.E.

    2009-01-01

    The giant garter snake (GGS; Thamnophis gigas) is a federally listed threatened species endemic to wetlands of the Central Valley of California. Habitat destruction has been the main factor in the decline of GGS populations, but the effects of contaminants on this species are unknown. To contribute to the recovery of these snakes, the U.S. Geological Survey (USGS) began studies of the life history and habitat use of GGSs in 1995. During a series of investigations conducted from 1995 to the present, specimens of dead GGSs were opportunistically collected from the Colusa National Wildlife Refuge (CNWR), the Natomas Basin, and other sites in northern California. Whole snakes were stored frozen for potential future analysis. As funding became available, we analyzed tissues of 23 GGSs to determine the concentrations of total mercury (Hg) and other trace elements in livers and concentrations of Hg in brains and tail clips. Mercury concentrations (??g/g, wet weight) ranged from 0.08 to 1.64 in livers, 0.01 to 0.18 in brains, and 0.02 to 0.32 in tail clips. In livers, geometric mean concentrations (??g/g, dry weight) of arsenic (25.7) and chromium (1.02) were higher than most values from studies of other snakes. Mercury concentrations in tail clips were positively correlated with concentrations in livers and brains, with the most significant correlations occurring at the Natomas Basin and when Natomas and CNWR were combined. Results indicate the value of using tail clips as a nonlethal bioindicator of contaminant concentrations. ?? 2008 US Government.

  3. Effects of mosquito control pesticides on competent queen conch (Strombus gigas) larvae.

    PubMed

    Delgado, Gabriel A; Glazer, Robert A; Wetzel, Dana

    2013-10-01

    Pesticides are applied seasonally in the Florida Keys to control nuisance populations of mosquitoes that pose a health threat to humans. There is, however, a need to investigate the effects of these pesticides on non-target marine organisms. We tested naled and permethrin, two mosquito adulticides used in the Keys, on a critical early life-history stage of queen conch (Strombus gigas). We conducted 12-h exposure experiments on competent (i.e., capable of undergoing metamorphosis) queen conch larvae using environmentally relevant pesticide concentrations. We found that there was little to no mortality and that the pesticides did not induce or interfere with metamorphosis. However, after introduction of a natural metamorphic cue (extract of the red alga Laurencia potei), a significantly greater proportion of larvae underwent metamorphosis in the pesticide treatments than in those with the alga alone. In addition to the morphogenetic pathway that induces metamorphosis when stimulated, there thus appears to be a regulatory pathway that enhances the response to metamorphic triggers, as suggested by the increased sensitivity of the queen conch larvae to the algal cue after pesticide exposure (i.e., the pesticides stimulated the regulatory pathway). The regulatory pathway probably plays a role in the identification of high-quality habitat for metamorphosis, as the increased response to the algal cue suggests. Aerial drift and runoff can carry these pesticides into nearshore waters, where they may act as a false signal of favorable conditions and facilitate metamorphosis in suboptimal habitat, thus adversely affecting recruitment in nearshore queen conch populations.

  4. Hemolymph chemistry and histopathological changes in Pacific oysters (Crassostrea gigas) in response to low salinity stress.

    PubMed

    Knowles, Graeme; Handlinger, Judith; Jones, Brian; Moltschaniwskyj, Natalie

    2014-09-01

    This study described seasonal differences in the histopathological and hemolymph chemistry changes in different family lines of Pacific oysters, Crassostrea gigas, in response to the stress of an abrupt change to low salinity, and mechanical grading. The most significant changes in pallial cavity salinity, hemolymph chemistry and histopathological findings occurred in summer at low salinity. In summer (water temperature 18°C) at low salinity, 9 (25.7% of full salinity), the mean pallial cavity salinity in oysters at day 3 was 19.8±1.6 (SE) and day 10 was 22.8±1.6 (SE) lower than oysters at salinity 35. Associated with this fall in pallial cavity salinity, mean hemolymph sodium for oysters at salinity 9 on day 3 and 10 were 297.2mmol/L±20(SE) and 350.4mmol/L±21.3(SE) lower than oysters at salinity 35. Similarly mean hemolymph potassium in oysters held at salinity 9 at day 3 and 10 were 5.6mmol/L±0.6(SE) and 7.9mmol/L±0.6 (SE) lower than oysters at salinity 35. These oysters at low salinity had expanded intercellular spaces and significant intracytoplasmic vacuolation distending the cytoplasm of epithelial cells in the alimentary tract and kidney and hemocyte infiltrate (diapedesis) within the alimentary tract wall. In contrast, in winter (water temperature 8°C) oyster mean pallial cavity salinity only fell at day 10 and this was by 6.0±0.6 (SE) compared to that of oysters at salinity 35. There were limited histopathological changes (expanded intercellular spaces and moderate intracytoplasmic vacuolation of renal epithelial cells) in these oysters at day 10 in low salinity. Mechanical grading and family line did not influence the oyster response to sudden low salinity. These findings provide additional information for interpretation of non-lethal, histopathological changes associated with temperature and salinity variation.

  5. Seasonality in the infection and invasion of Marteilioides chungmuensis in the Pacific oyster Crassostrea gigas.

    PubMed

    Tun, Kay Lwin; Shimizu, Yasuko; Yamanoi, Hideo; Yoshinaga, Tomoyoshi; Ogawa, Kazuo

    2008-07-07

    The protozoan parasite Marteilioides chungmuensis causes irregular enlargement of the ovary in the Pacific oyster Crassostrea gigas. The parasite invades the oyster through the epithelial tissue of the labial palp, replicates in the connective tissue, and then moves to the gonad, producing spores inside the oocytes. In this study the seasonality and invasion period of the parasite into the host was investigated over a 1 yr cycle. Uninfected 1 and 0 yr old (spat) oysters were placed in an epizootic area every month from July 2004 to July 2005 and September 2005 to March 2006, respectively, and left for 1 mo. Labial palps and gonad were sampled monthly and examined for infection by nested PCR and histological observations. Prevalence of infection detected by PCR was 70% or higher from August to October, but declined sharply in November and reached 7% or lower from February to April. To explain the low detection rate in winter, 1 yr old uninfected oysters were placed in an epizootic area in winter (water temperature: 8 to 10 degrees C) for 2 wk and then transferred to M. chungmuensis-free seawater at 24 degrees C. Although prevalence of infection was ca. 7% before transfer to heated seawater, levels of 87% were detected after 1 wk. After a 3 wk exposure to heated seawater, parasites were found in host oocytes by histological observation. It was concluded that the low prevalence in winter was due to insufficient replication of M. chungmuensis at low seawater temperatures, resulting in levels not detectable by nested PCR, and not to the absence of invasion.

  6. Quantitative trait locus analysis of stage-specific inbreeding depression in the Pacific oyster Crassostrea gigas.

    PubMed

    Plough, Louis V; Hedgecock, Dennis

    2011-12-01

    Inbreeding depression and genetic load have been widely observed, but their genetic basis and effects on fitness during the life cycle remain poorly understood, especially for marine animals with high fecundity and high, early mortality (type-III survivorship). A high load of recessive mutations was previously inferred for the Pacific oyster Crassostrea gigas, from massive distortions of zygotic, marker segregation ratios in F(2) families. However, the number, genomic location, and stage-specific onset of mutations affecting viability have not been thoroughly investigated. Here, we again report massive distortions of microsatellite-marker segregation ratios in two F(2) hybrid families, but we now locate the causative deleterious mutations, using a quantitative trait locus (QTL) interval-mapping model, and we characterize their mode of gene action. We find 14-15 viability QTL (vQTL) in the two families. Genotypic frequencies at vQTL generally suggest selection against recessive or partially recessive alleles, supporting the dominance theory of inbreeding depression. No epistasis was detected among vQTL, so unlinked vQTL presumably have independent effects on survival. For the first time, we track segregation ratios of vQTL-linked markers through the life cycle, to determine their stage-specific expression. Almost all vQTL are absent in the earliest life stages examined, confirming zygotic viability selection; vQTL are predominantly expressed before the juvenile stage (90%), mostly at metamorphosis (50%). We estimate that, altogether, selection on vQTL caused 96% mortality in these families, accounting for nearly all of the actual mortality. Thus, genetic load causes substantial mortality in inbred Pacific oysters, particularly during metamorphosis, a critical developmental transition warranting further investigation.

  7. Gene expression profiling of genetically determined growth variation in bivalve larvae (Crassostrea gigas).

    PubMed

    Meyer, E; Manahan, D T

    2010-03-01

    Growth rates in animals are governed by a wide range of biological factors, many of which remain poorly understood. To identify the genes that establish growth differences in bivalve larvae, we compared expression patterns in contrasting phenotypes (slow- and fast-growth) that were experimentally produced by genetic crosses of the Pacific oyster Crassostrea gigas. Based on transcriptomic profiling of 4.5 million cDNA sequence tags, we sequenced and annotated 181 cDNA clones identified by statistical analysis as candidates for differential growth. Significant matches were found in GenBank for 43% of clones (N=78), including 34 known genes. These sequences included genes involved in protein metabolism, energy metabolism and regulation of feeding activity. Ribosomal protein genes were predominant, comprising half of the 34 genes identified. Expression of ribosomal protein genes showed non-additive inheritance - i.e. expression in fast-growing hybrid larvae was different from average levels in inbred larvae from these parental families. The expression profiles of four ribosomal protein genes (RPL18, RPL31, RPL352 and RPS3) were validated by RNA blots using additional, independent crosses from the same families. Expression of RPL35 was monitored throughout early larval development, revealing that these expression patterns were established early in development (in 2-day-old larvae). Our findings (i) provide new insights into the mechanistic bases of growth and highlight genes not previously considered in growth regulation, (ii) support the general conclusion that genes involved in protein metabolism and feeding regulation are key regulators of growth, and (iii) provide a set of candidate biomarkers for predicting differential growth rates during animal development.

  8. Foraging ecology and movement patterns of jumbo squid (Dosidicus gigas) in the California Current System

    NASA Astrophysics Data System (ADS)

    Field, John C.; Elliger, Carl; Baltz, Ken; Gillespie, Graham E.; Gilly, William F.; Ruiz-Cooley, R. I.; Pearse, Devon; Stewart, Julia S.; Matsubu, William; Walker, William A.

    2013-10-01

    From 2002 to 2010, the jumbo squid (Dosidicus gigas) has been regularly encountered in large numbers throughout the California Current System (CCS). This species, usually found in subtropical waters, could affect coastal pelagic ecosystems and fisheries as both predator and prey. Neither the abundance of jumbo squid nor the optimal ocean conditions in which they flourish are well known. To understand better the potential impacts of this species on both commercial fisheries and on food-web structure we collected nearly 900 specimens from waters of the CCS, covering over 20° of latitude, over a range of depths and seasons. We used demographic information (size, sex, and maturity state) and analyzed stomach contents using morphological and molecular methods to best understand the foraging ecology of this species in different habitats of the CCS. Squid were found to consume a broad array of prey. Prey in offshore waters generally reflected the forage base reported in previous studies (mainly mesopelagic fishes and squids), whereas in more coastal waters (shelf, shelf break and slope habitats) squid foraged on a much broader mix that included substantial numbers of coastal pelagic fishes (Pacific herring and northern anchovy, as well as osmerids and salmonids in northern waters) and groundfish (Pacific hake, several species of rockfish and flatfish). We propose a seasonal movement pattern, based on size and maturity distributions along with qualitative patterns of presence or absence, and discuss the relevance of both the movement and distribution of jumbo squid over space and time. We find that jumbo squid are a generalist predator, which feeds primarily on small, pelagic or mesopelagic micronekton but also on larger fishes when they are available. We also conclude that interactions with and potential impacts on ecosystems likely vary over space and time, in response to both seasonal movement patterns and highly variable year-to-year abundance of the squid themselves.

  9. Sequential Isotopic Signature Along Gladius Highlights Contrasted Individual Foraging Strategies of Jumbo Squid (Dosidicus gigas)

    PubMed Central

    Lorrain, Anne; Argüelles, Juan; Alegre, Ana; Bertrand, Arnaud; Munaron, Jean-Marie; Richard, Pierre; Cherel, Yves

    2011-01-01

    Background Cephalopods play a major role in marine ecosystems, but knowledge of their feeding ecology is limited. In particular, intra- and inter-individual variations in their use of resources has not been adequatly explored, although there is growing evidence that individual organisms can vary considerably in the way they use their habitats and resources. Methodology/Principal Findings Using δ13C and δ15N values of serially sampled gladius (an archival tissue), we examined high resolution variations in the trophic niche of five large (>60 cm mantle length) jumbo squids (Dosidicus gigas) that were collected off the coast of Peru. We report the first evidence of large inter-individual differences in jumbo squid foraging strategies with no systematic increase of trophic level with size. Overall, gladius δ13C values indicated one or several migrations through the squid's lifetime (∼8–9 months), during which δ15N values also fluctuated (range: 1 to 5‰). One individual showed an unexpected terminal 4.6‰ δ15N decrease (more than one trophic level), thus indicating a shift from higher- to lower-trophic level prey at that time. The data illustrate the high diversity of prey types and foraging histories of this species at the individual level. Conclusions/Significance The isotopic signature of gladii proved to be a powerful tool to depict high resolution and ontogenic variations in individual foraging strategies of squids, thus complementing traditional information offered by stomach content analysis and stable isotopes on metabolically active tissues. The observed differences in life history strategies highlight the high degree of plasticity of the jumbo squid and its high potential to adapt to environmental changes. PMID:21779391

  10. Construction and evaluation of a high-density SNP array for the Pacific oyster (Crassostrea gigas)

    PubMed Central

    Li, Chunyan; Wang, Wei; Li, Busu; Li, Li

    2017-01-01

    Single nucleotide polymorphisms (SNPs) are widely used in genetics and genomics research. The Pacific oyster (Crassostrea gigas) is an economically and ecologically important marine bivalve, and it possesses one of the highest levels of genomic DNA variation among animal species. Pacific oyster SNPs have been extensively investigated; however, the mechanisms by which these SNPs may be used in a high-throughput, transferable, and economical manner remain to be elucidated. Here, we constructed an oyster 190K SNP array using Affymetrix Axiom genotyping technology. We designed 190,420 SNPs on the chip; these SNPs were selected from 54 million SNPs identified through re-sequencing of 472 Pacific oysters collected in China, Japan, Korea, and Canada. Our genotyping results indicated that 133,984 (70.4%) SNPs were polymorphic and successfully converted on the chip. The SNPs were distributed evenly throughout the oyster genome, located in 3,595 scaffolds with a length of ~509.4 million; the average interval spacing was 4,210 bp. In addition, 111,158 SNPs were distributed in 21,050 coding genes, with an average of 5.3 SNPs per gene. In comparison with genotypes obtained through re-sequencing, ~69% of the converted SNPs had a concordance rate of >0.971; the mean concordance rate was 0.966. Evaluation based on genotypes of full-sib family individuals revealed that the average genotyping accuracy rate was 0.975. Carrying 133 K polymorphic SNPs, our oyster 190K SNP array is the first commercially available high-density SNP chip for mollusks, with the highest throughput. It represents a valuable tool for oyster genome-wide association studies, fine linkage mapping, and population genetics. PMID:28328985

  11. Horseshoe crab, Tachypleus gigas (Müller, 1785) spawning population at Balok Beach, Kuantan, Pahang, Malaysia.

    PubMed

    Tan, A N; Christianus, A; Shakibazadeh, S; Hajeb, P

    2012-07-01

    Local and regional decline of Asian horseshoe crabs has spurred a study on its spawning population at Balok Beach, Kuantan, Pahang, Malaysia. This location was identified as spawning site due to the occurrence of horseshoe crab spawning pairs and nests. Size-frequency, length-weight relationships, sex ratio and epibiont infestation of Tachypleus gigas were studied. Instar stage was estimated based on prosomal width. Condition of the horseshoe crab carapace was reported. Visual search technique of horseshoe crab was conducted during high tide of new and full moons. Prosomal, opisthosomal and telson length and weight of each horseshoe crab were measured. Largest female was recorded with mean prosomal length and width of 154.4 and 246.9 mm, respectively. About 69.8% of the males belonged to size group of 151-200 mm and 53.3% of females were grouped into 201-250 mm. All individuals were of fourteenth to sixteenth instar stages. Sex ratio varied from 0.313 to 2.5 and attributed to commercial harvest and monsoon season. Sand sediment of study site showed 93% of fine sands with grain size ranged from 120 to 250 microm. Acorn and pedunculate barnacle, conical and flat slipper shells were found on the carapace of the specimens. Most males had damaged eyes and carapaces while females with broken telsons. Body damages of about 19.9% on the specimens were likely due to nearby fishing activities. Lack of satellite male indicated low spawning population. The finding of this study showed that the species is extremely threatened by human activities and coastal development.

  12. An integrin from oyster Crassostrea gigas mediates the phagocytosis toward Vibrio splendidus through LPS binding activity.

    PubMed

    Jia, Zhihao; Zhang, Tao; Jiang, Shuai; Wang, Mengqiang; Cheng, Qi; Sun, Mingzhe; Wang, Lingling; Song, Linsheng

    2015-11-01

    Integrins are a family of cell adhesion molecules which play important roles in the regulation of cell adhesion, migration, proliferation, apoptosis and phagocytosis. In the present study, the immune function of an integrin from the oyster Crassostrea gigas (designated CgIntegrin) was characterized to understand the regulatory mechanism of hemocyte phagocytosis toward different microbes. The full-length cDNA of CgIntegrin was 2571 bp with an open reading frame (ORF) of 2397 bp, encoding a polypeptide of 799 amino acids. The mRNA transcripts of CgIntegrin were predominantly detected in hemocytes, gonad and adductor muscle, while lowly in hepatopancreas, mantle and gill. The mRNA expression level was up-regulated at 6 h post lipopolysaccharide (LPS) stimulation (p < 0.01), while no significant change was observed after peptidoglycan (PGN) stimulation. The oyster hemocytes with relative high CgIntegrin expression level exhibited different phagocytic abilities towards different microorganism and particles, such as Gram-positive bacteria Vibrio splendidus, Gram-negative bacteria Staphylococcus aureus and latex beads. Moreover, the phagocytic rate towards V. splendidus was significantly decreased after the blockade of CgIntegrin using the polyclonal antibody. The recombinant CgIntegrin (rCgIntegrin) displayed agglutinating activity towards V. splendidus but not S. aureus and Y. lipolytica. It also exhibited a higher binding affinity towards LPS (compared to rTrx group) in a dose-dependent manner with the apparent dissociation constant (Kd) of 5.53 × 10(-6) M. The results indicated that CgIntegrin served as a pattern recognition receptor with LPS binding activity, which could directly bind to V. splendidus and enhance the phagocytosis of oyster hemocytes.

  13. Quantitative Trait Locus Analysis of Stage-Specific Inbreeding Depression in the Pacific Oyster Crassostrea gigas

    PubMed Central

    Plough, Louis V.; Hedgecock, Dennis

    2011-01-01

    Inbreeding depression and genetic load have been widely observed, but their genetic basis and effects on fitness during the life cycle remain poorly understood, especially for marine animals with high fecundity and high, early mortality (type-III survivorship). A high load of recessive mutations was previously inferred for the Pacific oyster Crassostrea gigas, from massive distortions of zygotic, marker segregation ratios in F2 families. However, the number, genomic location, and stage-specific onset of mutations affecting viability have not been thoroughly investigated. Here, we again report massive distortions of microsatellite-marker segregation ratios in two F2 hybrid families, but we now locate the causative deleterious mutations, using a quantitative trait locus (QTL) interval-mapping model, and we characterize their mode of gene action. We find 14–15 viability QTL (vQTL) in the two families. Genotypic frequencies at vQTL generally suggest selection against recessive or partially recessive alleles, supporting the dominance theory of inbreeding depression. No epistasis was detected among vQTL, so unlinked vQTL presumably have independent effects on survival. For the first time, we track segregation ratios of vQTL-linked markers through the life cycle, to determine their stage-specific expression. Almost all vQTL are absent in the earliest life stages examined, confirming zygotic viability selection; vQTL are predominantly expressed before the juvenile stage (90%), mostly at metamorphosis (50%). We estimate that, altogether, selection on vQTL caused 96% mortality in these families, accounting for nearly all of the actual mortality. Thus, genetic load causes substantial mortality in inbred Pacific oysters, particularly during metamorphosis, a critical developmental transition warranting further investigation. PMID:21940682

  14. The shell organic matrix of the crossed lamellar queen conch shell (Strombus gigas).

    PubMed

    Osuna-Mascaró, Antonio; Cruz-Bustos, Teresa; Benhamada, Sana; Guichard, Nathalie; Marie, Benjamin; Plasseraud, Laurent; Corneillat, Marion; Alcaraz, Gérard; Checa, Antonio; Marin, Frédéric

    2014-02-01

    In molluscs, the shell organic matrix comprises a large set of biomineral-occluded proteins, glycoproteins and polysaccharides that are secreted by the calcifying mantle epithelium, and are supposed to display several functions related to the synthesis of the shell. In the present paper, we have characterized biochemically the shell matrix associated to the crossed-lamellar structure of the giant queen conch Strombus gigas. The acid-soluble (ASM) and acid-insoluble (AIM) matrices represent an extremely minor fraction of the shell. Both are constituted of polydisperse and of few discrete proteins among which three fractions, obtained by preparative SDS-PAGE and named 1P3, 2P3 and 3P3, are dominant and were further characterized. Compared to other matrices, the acid-soluble matrix is weakly glycosylated (3%) and among the discrete components, only 3P3 seems noticeably glycosylated. The monosaccharide composition of the ASM shows that mannose represents the main monosaccharide. To our knowledge, this is the first report of a high ratio of this sugar in a skeletal matrix. Furthermore, the ASM interacts with the in vitro crystallization of calcium carbonate, but this interaction is moderate. It differs from that of the isolated 1P3 fraction but is similar to that of the 2P3 and 3P3 fractions. At last, antibodies developed from the 3P3 fraction were used to localize this fraction within the shell by immunogold. This study is the first one aiming at characterizing the organic matrix associated to the crossed-lamellar structure of the queen conch shell.

  15. Metal speciation and toxicity of Tamar Estuary water to larvae of the Pacific oyster, Crassostrea gigas.

    PubMed

    Money, Cathryn; Braungardt, Charlotte B; Jha, Awadhesh N; Worsfold, Paul J; Achterberg, Eric P

    2011-07-01

    As part of the PREDICT Tamar Workshop, the toxicity of estuarine waters in the Tamar Estuary (southwest England) was assessed by integration of metal speciation determination with bioassays. High temporal resolution metal speciation analysis was undertaken in situ by deployment of a Voltammetric In situ Profiling (VIP) system. The VIP detects Cd (cadmium), Pb (lead) and Cu (copper) species smaller than 4 nm in size and this fraction is termed 'dynamic' and considered biologically available. Cadmium was mainly present in the dynamic form and constituted between 56% and 100% of the total dissolved concentration, which was determined subsequently in the laboratory in filtered discrete samples. In contrast, the dynamic Pb and Cu fractions were less important, with a much larger proportion of these metals associated with organic ligands and/or colloids (45-90% Pb and 46-85% Cu), which probably reduced the toxicological impact of these elements in this system. Static toxicity tests, based on the response of Crassostrea gigas larva exposed to discrete water samples showed a high level of toxicity (up to 100% abnormal development) at two stations in the Tamar, particularly during periods of the tidal cycle when the influence of more pristine coastal water was at its lowest. Competitive ligand-exchange Cu titrations showed that natural organic ligands reduced the free cupric ion concentration to levels that were unlikely to have been the sole cause of the observed toxicity. Nonetheless, it is probable that the combined effect of the metals determined in this work contributed significantly to the bioassay response.

  16. Heterologous expression of the Crassostrea gigas (Pacific oyster) alternative oxidase in the yeast Saccharomyces cerevisiae.

    PubMed

    Robertson, Aaron; Schaltz, Kyle; Neimanis, Karina; Staples, James F; McDonald, Allison E

    2016-10-01

    Alternative oxidase (AOX) is a terminal oxidase within the inner mitochondrial membrane (IMM) present in many organisms where it functions in the electron transport system (ETS). AOX directly accepts electrons from ubiquinol and is therefore capable of bypassing ETS Complexes III and IV. The human genome does not contain a gene coding for AOX, so AOX expression has been suggested as a gene therapy for a range of human mitochondrial diseases caused by genetic mutations that render Complex III and/or IV dysfunctional. An effective means of screening mutations amenable to AOX treatment remains to be devised. We have generated such a tool by heterologously expressing AOX from the Pacific oyster (Crassostrea gigas) in the yeast Saccharomyces cerevisiae under the control of a galactose promoter. Our results show that this animal AOX is monomeric and is correctly targeted to yeast mitochondria. Moreover, when expressed in yeast, Pacific oyster AOX is a functional quinol oxidase, conferring cyanide-resistant growth and myxothiazol-resistant oxygen consumption to yeast cells and isolated mitochondria. This system represents a high-throughput screening tool for determining which Complex III and IV genetic mutations in yeast will be amenable to AOX gene therapy. As many human genes are orthologous to those found in yeast, our invention represents an efficient and cost-effective way to evaluate viable research avenues. In addition, this system provides the opportunity to learn more about the localization, structure, and regulation of AOXs from animals that are not easily reared or manipulated in the lab.

  17. Effect of Carbonate Chemistry Alteration on the Early Embryonic Development of the Pacific Oyster (Crassostrea gigas)

    PubMed Central

    Gazeau, Frédéric; Gattuso, Jean-Pierre; Greaves, Mervyn; Elderfield, Henry; Peene, Jan; Heip, Carlo H. R.; Middelburg, Jack J.

    2011-01-01

    Ocean acidification, due to anthropogenic CO2 absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on the early life stages of mollusks that are supposedly more sensitive to environmental disturbances than adult stages. Although these studies have shown decreased growth rates and increased proportions of abnormal development under low pH conditions, they did not allow attribution to pH induced changes in physiology or changes due to a decrease in aragonite saturation state. This study aims to assess the impact of several carbonate-system perturbations on the growth of Pacific oyster (Crassostrea gigas) larvae during the first 3 days of development (until shelled D-veliger larvae). Seawater with five different chemistries was obtained by separately manipulating pH, total alkalinity and aragonite saturation state (calcium addition). Results showed that the developmental success and growth rates were not directly affected by changes in pH or aragonite saturation state but were highly correlated with the availability of carbonate ions. In contrast to previous studies, both developmental success into viable D-shaped larvae and growth rates were not significantly altered as long as carbonate ion concentrations were above aragonite saturation levels, but they strongly decreased below saturation levels. These results suggest that the mechanisms used by these organisms to regulate calcification rates are not efficient enough to compensate for the low availability of carbonate ions under corrosive conditions. PMID:21860666

  18. The immunomodulation of inducible hydrogen sulfide in Pacific oyster Crassostrea gigas.

    PubMed

    Sun, Zhibin; Wang, Lingling; Zhang, Tao; Zhou, Zhi; Jiang, Qiufen; Yi, Qilin; Yang, Chuanyan; Qiu, Limei; Song, Linsheng

    2014-10-01

    Hydrogen sulfide (H2S) is an important gasotransmitter, which plays indispensable roles in cardiovascular, nervous and immune systems of vertebrates. However, the information about the immunomodulation of H2S in invertebrates is still very limited. In the present study, the temporal expression profile of cystathionine γ lyase in oyster Crassostrea gigas (CgCSE) was investigated after the oysters were stimulated by lipopolysaccharide. The expression levels of CgCSE mRNA transcripts in hemocytes increased significantly at 12h (1.31-fold of the PBS group, P<0.05) after LPS stimulation. The immunomodulation of inducible H2S in oyster was examined by monitoring the alterations of both cellular and humoral immune parameters in response to the stimulations of LPS, LPS+Na2S and LPS+propargylglycine (PAG). The total hemocyte counts (THC) and hemolymph PO activity increased significantly after LPS stimulation, and the increase could be further enhanced by adding PAG, while inhibited by appending Na2S. The phagocytosis activity of hemocytes was also increased firstly after LPS treatment, and the increase was enhanced by adding Na2S but inhibited after appending PAG. The anti-bacterial activity in hemolymph increased at 3h post LPS treatment, and then decreased after adding PAG. The total SOD activity of hemolymph was also elevated at 6h post LPS treatment, and the elevated activity was depressed by adding Na2S. These results collectively indicated that H2S might play crucial roles in the immune response of oyster via modulating the turnover and phagocytosis of hemocytes, and regulating the anti-bacterial activity and proPO activation in the hemolymph.

  19. Free Breathing Static Dehumidification Systems.

    DTIC Science & Technology

    1987-01-01

    1?336 FREE NNERTHIN STATIC DMIDIFICATIOU SYS*kNS(U) RJR In__ FORME PRCKRGING EVJRTIN ROENCY WIIT-RTTERMO WD ON S A M~Y Jfh 97 DST -7-R-1 LOL lSSFFI...0 . LiW- M -. ’*5 iq - a . L O 37 Figure 12. Field Layout at SM-ALC/ DST , McClellan AFB CA .tr 4j w, I , D 4.- 4, 4J 4) :3 4j CCD ko LL o. 0.U UU -4 4...USAeLE11 I Wash DC 20330 HQ Ar’SC/LG’ I O)C-ALC/ DST Tinker Ar’B OK 73145 U0-ALC/ OST 1 Hill AFB UT 84406 SA-ALC/ DST i I. Kelly AeBN TIX 78241 SM-ALC

  20. DNA barcoding reveals that the common cupped oyster in Taiwan is the Portuguese oyster Crassostrea angulata (Ostreoida; Ostreidae), not C. gigas.

    PubMed

    Hsiao, Sheng-Tai; Chuang, Shin-Chang; Chen, Kao-Sung; Ho, Ping-Ho; Wu, Chi-Lun; Chen, Chaolun Allen

    2016-09-26

    The Pacific cupped oyster, Crassostrea gigas, is one of the major aquacultural shellfish species that has been introduced to Europe and America from its native source in the West Pacific. In Taiwan, the cultivated cupped oysters along the west coast have been identified as C. gigas for over centuries; however, several molecular phylogenetic studies have cast doubt upon the existence of this species in Taiwan and adjacent waters. Indeed, our analyses of mitochondrial cytochrome oxidase I (COI) sequences from 313 Crassostrea collected from 12 locations along Taiwanese and southern Chinese coastlines confirm that all samples were the Portuguese oyster, C. angulata, rather than C. gigas. Multiple lines of evidence, including haplotypic and nucleotide diversity of the COI gene, demographic history, and population genetics, suggest that Taiwanese C. angulata is unique, probably experienced a sudden population expansion after the Last Glacial Maxima around 20,000 years ago, and has a significantly limited genetic connectivity across the Taiwan Strait. Our study applies an extended sampling and DNA barcoding to confirm the absence of C. gigas in natural and cultivated populations in Taiwan and southern China, where we only found C. angulata. We highlight the importance of conserving the gene pool of the C. angulata population in Taiwan, particularly considering the current threats by large-scale environmental disturbances such as marine pollution, habitat destruction, and climate change.

  1. DNA barcoding reveals that the common cupped oyster in Taiwan is the Portuguese oyster Crassostrea angulata (Ostreoida; Ostreidae), not C. gigas

    NASA Astrophysics Data System (ADS)

    Hsiao, Sheng-Tai; Chuang, Shin-Chang; Chen, Kao-Sung; Ho, Ping-Ho; Wu, Chi-Lun; Chen, Chaolun Allen

    2016-09-01

    The Pacific cupped oyster, Crassostrea gigas, is one of the major aquacultural shellfish species that has been introduced to Europe and America from its native source in the West Pacific. In Taiwan, the cultivated cupped oysters along the west coast have been identified as C. gigas for over centuries; however, several molecular phylogenetic studies have cast doubt upon the existence of this species in Taiwan and adjacent waters. Indeed, our analyses of mitochondrial cytochrome oxidase I (COI) sequences from 313 Crassostrea collected from 12 locations along Taiwanese and southern Chinese coastlines confirm that all samples were the Portuguese oyster, C. angulata, rather than C. gigas. Multiple lines of evidence, including haplotypic and nucleotide diversity of the COI gene, demographic history, and population genetics, suggest that Taiwanese C. angulata is unique, probably experienced a sudden population expansion after the Last Glacial Maxima around 20,000 years ago, and has a significantly limited genetic connectivity across the Taiwan Strait. Our study applies an extended sampling and DNA barcoding to confirm the absence of C. gigas in natural and cultivated populations in Taiwan and southern China, where we only found C. angulata. We highlight the importance of conserving the gene pool of the C. angulata population in Taiwan, particularly considering the current threats by large-scale environmental disturbances such as marine pollution, habitat destruction, and climate change.

  2. Metabolic Cost of Protein Synthesis in Larvae of the Pacific Oyster (Crassostrea gigas) Is Fixed Across Genotype, Phenotype, and Environmental Temperature.

    PubMed

    Lee, Jimmy W; Applebaum, Scott L; Manahan, Donal T

    2016-06-01

    The energy made available through catabolism of specific biochemical reserves is constant using standard thermodynamic conversion equivalents (e.g., 24.0 J mg protein(-1)). In contrast, measurements reported for the energy cost of synthesis of specific biochemical constituents are highly variable. In this study, we measured the metabolic cost of protein synthesis and determined whether this cost was influenced by genotype, phenotype, or environment. We focused on larval stages of the Pacific oyster Crassostrea gigas, a species that offers several experimental advantages: availability of genetically pedigreed lines, manipulation of ploidy, and tractability of larval forms for in vivo studies of physiological processes. The cost of protein synthesis was measured in larvae of C. gigas for 1) multiple genotypes, 2) phenotypes with different growth rates, and 3) different environmental temperatures. For all treatments, the cost of protein synthesis was within a narrow range--near the theoretical minimum--with a fixed cost (mean ± one standard error, n = 21) of 2.1 ± 0.2 J (mg protein synthesized)(-1) We conclude that there is no genetic variation in the metabolic cost of protein synthesis, thereby simplifying bioenergetic models. Protein synthesis is a major component of larval metabolism in C. gigas, accounting for more than half the metabolic rate in diploid (59%) and triploid larvae (54%). These results provide measurements of metabolic cost of protein synthesis in larvae of C. gigas, an indicator species for impacts of ocean change, and provide a quantitative basis for evaluating the cost of resilience.

  3. DNA barcoding reveals that the common cupped oyster in Taiwan is the Portuguese oyster Crassostrea angulata (Ostreoida; Ostreidae), not C. gigas

    PubMed Central

    Hsiao, Sheng-Tai; Chuang, Shin-Chang; Chen, Kao-Sung; Ho, Ping-Ho; Wu, Chi-Lun; Chen, Chaolun Allen

    2016-01-01

    The Pacific cupped oyster, Crassostrea gigas, is one of the major aquacultural shellfish species that has been introduced to Europe and America from its native source in the West Pacific. In Taiwan, the cultivated cupped oysters along the west coast have been identified as C. gigas for over centuries; however, several molecular phylogenetic studies have cast doubt upon the existence of this species in Taiwan and adjacent waters. Indeed, our analyses of mitochondrial cytochrome oxidase I (COI) sequences from 313 Crassostrea collected from 12 locations along Taiwanese and southern Chinese coastlines confirm that all samples were the Portuguese oyster, C. angulata, rather than C. gigas. Multiple lines of evidence, including haplotypic and nucleotide diversity of the COI gene, demographic history, and population genetics, suggest that Taiwanese C. angulata is unique, probably experienced a sudden population expansion after the Last Glacial Maxima around 20,000 years ago, and has a significantly limited genetic connectivity across the Taiwan Strait. Our study applies an extended sampling and DNA barcoding to confirm the absence of C. gigas in natural and cultivated populations in Taiwan and southern China, where we only found C. angulata. We highlight the importance of conserving the gene pool of the C. angulata population in Taiwan, particularly considering the current threats by large-scale environmental disturbances such as marine pollution, habitat destruction, and climate change. PMID:27666088

  4. Reproduction in the giant clams Tridacna gigas and T. derasa in situ on the north-central Great Barrier Reef, Australia, and Papua New Guinea

    NASA Astrophysics Data System (ADS)

    Braley, Richard D.

    1984-12-01

    Small groups of T. gigas and a single individual of T. derasa have been observed to spawn sperm in nature during the austral summer on the Great Barrier Reef. In T. gigas diel periodicity to the spawning generally coincided with incoming tides near second (full), third and fourth (new) quarters of the moon phase. Intense spawning ranged from 30 min to 2 1/2 h, with spawning contractions occurring every 2 3 min. Eggs were never observed being spawned in nature. A new technique, an egg catching device, was used for sampling eggs of T. gigas which were observed spawning sperm. Results indicated that the egg phase of spawning did not follow spawning of sperm. Some clams which do not respond to a spawning neighbour may be reproductively inactive. In 70% of observations of nearest spawning neighbours the clams were within 9 m of one another. A hypodermic extraction technique was used for clam gonadal material. Examination of tissue suggested a potential early to mid-austral summer spawning for T. gigas, and to a lesser degree for T. derasa.

  5. Identification of molecular and physiological responses to chronic environmental challenge in an invasive species: the Pacific oyster, Crassostrea gigas

    PubMed Central

    Clark, Melody S; Thorne, Michael A S; Amaral, Ana; Vieira, Florbela; Batista, Frederico M; Reis, João; Power, Deborah M

    2013-01-01

    Understanding the environmental responses of an invasive species is critical in predicting how ecosystem composition may be transformed in the future, especially under climate change. In this study, Crassostrea gigas, a species well adapted to the highly variable intertidal environment, was exposed to the chronic environmental challenges of temperature (19 and 24°C) and pH (ambient seawater and a reduction of 0.4 pH units) in an extended 3-month laboratory-based study. Physiological parameters were measured (condition index, shell growth, respiration, excretion rates, O:N ratios, and ability to repair shell damage) alongside molecular analyses. Temperature was by far the most important stressor, as demonstrated by reduced condition indexes and shell growth at 24°C, with relatively little effect detected for pH. Transcriptional profiling using candidate genes and SOLiD sequencing of mantle tissue revealed that classical “stress” genes, previously reported to be upregulated under acute temperature challenges, were not significantly expressed in any of the treatments, emphasizing the different response between acute and longer term chronic stress. The transcriptional profiling also elaborated on the cellular responses underpinning the physiological results, including the identification of the PI3K/AKT/mTOR pathway as a potentially novel marker for chronic environmental challenge. This study represents a first attempt to understand the energetic consequences of cumulative thermal stress on the intertidal C. gigas which could significantly impact on coastal ecosystem biodiversity and function in the future. PMID:24223268

  6. Metal-binding protein in the pacific oyster, Crassostrea gigas: assessment of the protein as a biochemical environmental indicator

    SciTech Connect

    Imber, B.E.; Thompson, J.A.J.; Ward, S.

    1987-04-01

    In this paper the determination of metal-binding proteins (MBP) in the Pacific Oyster (Crassostrea gigas) is reported. The objectives of this study were to employ a simple, cost-effective method for quantifying MBP and to assess this parameter for possible use as an indicator of identifiable sources of metal input to biological systems. Abnormally high quantities of zinc had been found previously in C. gigas growing in waters adjacent to the Kraft pump mill at Crofton, British Columbia. From 1971 to 1973 oysters near the effluent outfalls were found to have body-burden zinc six to ten times the zinc concentrations found in reference specimens. Zinc dithionite was used in the pulping process at the mill until 1973. Subsequent to a change to sodium dithionite, concentrations of zinc in oysters decreased steadily. A second potential source of contamination is sited directly south of the pulp mill. In this case, leaching of copper and zinc from smelter slag into Osborn Bay has been identified.

  7. Ostreid herpesvirus 1 (OsHV-1) detection among three successive generations of Pacific oysters (Crassostrea gigas).

    PubMed

    Barbosa-Solomieu, V; Dégremont, L; Vázquez-Juárez, R; Ascencio-Valle, F; Boudry, P; Renault, T

    2005-01-01

    Ostreid Herpesvirus 1 (OsHV-1) was likely detected in Pacific oysters, Crassostrea gigas, at different stages of development. Viral infections were associated with high mortality rates in the spat and larvae. Furthermore, the persistance of OsHV-1 in asymptomatic adults was demonstrated by detection of viral DNA and proteins. In the present study, three successive generations of C. gigas (G0 and G1 parental oysters, G1 and G2 larvae) were screened for OsHV-1 by PCR. Viral DNA was detected in 2-day-old larvae, indicating that infection may take place at very early stages. Although results strengthen the hypothesis of a vertical transmission, it was not possible to predict the issue of a particular type of cross. Indeed, the detection of viral DNA in parental oysters did not systematically correspond to a productive infection or result in a successful transmission to the progeny. However, the infective status of the parents appeared to have an influence on both the infection and the survival rates of the progeny. Crosses involving an OsHV-1 infected male and a non-infected female resulted in hatching and larval survival rates statistically lower than those observed in the other types of cross. These results suggest that OsHV-1-infected females may transmit to their offspring some kind of protection or resistance against viral infection.

  8. Detection of different variants of Ostreid Herpesvirus 1 in the Pacific oyster, Crassostrea gigas between 2008 and 2010.

    PubMed

    Martenot, Claire; Oden, Elise; Travaillé, Emmanuelle; Malas, Jean-Paul; Houssin, Maryline

    2011-09-01

    Since summer 2008, high mortality rates of young Pacific oysters Crassostrea gigas have been recorded in association with the detection of the Ostreid Herpesvirus 1 (OsHV-1). A new variant called μVar has been recently described, characterized mainly by 12 consecutive deletions followed by one deletion of an adenine in the C region. The purpose of this study is to characterize the genotype (variants or OsHV-1 reference) of 300 positive samples of C. gigas analyzed between July 2008 and July 2010 collected along the French, Jersey, and Irish coasts. Samples were quantified by TaqMan PCR, amplified with conventional PCR, targeting the area of the deletion, and then sequenced. Eighty-seven percent of the samples were characterized and the OsHV-1 μVar was detected in 257 oyster samples. The genotype OsHV-1 reference was never detected during the 25 months of the present survey. Thirty-eight samples could not be determined and the majority of them had a low viral load. A novel genotype containing only 9 consecutive deletions named OsHV-1 μVar Δ9 was found in 5 samples. These observations indicate the emergence of different OsHV-1 variants.

  9. In vitro research of anti-HSV-1 activity in different extracts from Pacific oysters Crassostrea gigas.

    PubMed

    Olicard, Cécile; Didier, Yohann; Marty, Christel; Bourgougnon, Nathalie; Renault, Tristan

    2005-11-09

    Mortalities related to the detection of Ostreid Herpesvirus 1 (OsHV-1) have been previously reported in France among larvae and spat of the Pacific oyster Crassostrea gigas. Adult oysters appear less sensitive to herpesvirus infections, although OsHV-1 has been detected in adults without signs of disease or mortality. This suggests that the virus is able to persist in its host and that adult oysters may be able to control OsHV-1 infection. Little is known about antiviral substances in invertebrates. The present work concerns the research of antiviral substances in adult oyster C. gigas, where putative antiviral activities were monitored using 3 strategies: (1) in metabolites with variable polarity, (2) in peptidic extracts and (3) in crude haemolymph. In vitro antiviral assays were based on inhibition of Herpes simplex virus type 1 (HSV-1) replication in Vero cell monolayers. All extracts presented no cytotoxicity. Antiviral activity was detected in the fresh filtered haemolymph (EC50:425 microg ml(-1)) and seasonal variation of the haemolymph antiviral activity was monitored.

  10. Ostreid herpesvirus type 1 genomic diversity in wild populations of Pacific oyster Crassostrea gigas from Italian coasts.

    PubMed

    Burioli, E A V; Prearo, M; Riina, M V; Bona, M C; Fioravanti, M L; Arcangeli, G; Houssin, M

    2016-06-01

    Ostreid herpesvirus 1 (OsHV-1) is a significant pathogen affecting the young Pacific oyster Crassostrea gigas, worldwide. A new variant, OsHV-1 μVar, has been associated with recurrent mortality events in Europe since 2008. Epidemiological data collection is key for global risk assessment; however little is known about health status and genotypes present in European wild oyster beds. Most studies to date have involved only cultivated individuals during mortality events, and reported low genotype diversity. With this study, conducted along the Italian coasts, we investigated for the first time the presence of OsHV-1 in European natural oyster beds. Analysis of three genomic regions revealed the presence of at least nine different genotypes, including two variants close to the OsHV-1 reference, known since the early 1990s but with no European record reported since 2010, and highlights relevant genotype diversity in natural environment. Phylogenetic analysis distinguished two distinct clusters and geographical distribution of genotypes, with the exception of a variant very closely related to the μVar, which appeared the single genotype present in all the Adriatic sites. Interestingly, these wild symptom free populations could represent, in Europe, an accessible alternative to the import of OsHV-1-resistant oyster strains from the East Pacific, the native area of C. gigas, avoiding the high-risk of non-native marine species and new pathogen introductions.

  11. Structural studies on Desulfovibrio gigas cytochrome c3 by two-dimensional 1H-nuclear-magnetic-resonance spectroscopy.

    PubMed Central

    Piçarra-Pereira, M A; Turner, D L; LeGall, J; Xavier, A V

    1993-01-01

    Several aromatic amino acid residues and haem resonances in the fully reduced form of Desulfovibrio gigas cytochrome c3 are assigned, using two-dimensional 1H n.m.r., on the basis of the interactions between the protons of the aromatic amino acids and the haem protons as well as the intrahaem distances known from the X-ray structure [Kissinger (1989) Ph.D. Thesis, Washington State University]. The interhaem interactions observed in the n.m.r. spectra are in full agreement with the D. gigas X-ray structure and also with the n.m.r. data from Desulfovibrio vulgaris (Hildenborough) [Turner, Salgueiro, LeGall and Xavier (1992) Eur. J. Biochem. 210, 931-936]. The good correlation between the calculated ring-current shifts and the observed chemical shifts strongly supports the present assignments. Observation of the two-dimensional nuclear-Overhauser-enhancement spectra of the protein in the reduced, intermediate and fully oxidized stages led to the ordering of the haems in terms of their midpoint redox potentials and their identification in the X-ray structure. The first haem to oxidize is haem I, followed by haems II, III and IV, numbered according to the Cys ligand positions in the amino acid sequences [Mathews (1985) Prog. Biophys. Mol. Biol. 54, 1-56]. Although the haem core architecture is the same for the different Desulfovibrio cytochromes c3, the order of redox potentials is different. PMID:8397514

  12. Chromogenic behaviors of the Humboldt squid (Dosidicus gigas) studied in situ with an animal-borne video package.

    PubMed

    Rosen, Hannah; Gilly, William; Bell, Lauren; Abernathy, Kyler; Marshall, Greg

    2015-01-15

    Dosidicus gigas (Humboldt or jumbo flying squid) is an economically and ecologically influential species, yet little is known about its natural behaviors because of difficulties in studying this active predator in its oceanic environment. By using an animal-borne video package, National Geographic's Crittercam, we were able to observe natural behaviors in free-swimming D. gigas in the Gulf of California with a focus on color-generating (chromogenic) behaviors. We documented two dynamic displays without artificial lighting at depths of up to 70 m. One dynamic pattern, termed 'flashing' is characterized by a global oscillation (2-4 Hz) of body color between white and red. Flashing was almost always observed when other squid were visible in the video frame, and this behavior presumably represents intraspecific signaling. Amplitude and frequency of flashing can be modulated, and the phase relationship with another squid can also be rapidly altered. Another dynamic display termed 'flickering' was observed whenever flashing was not occurring. This behavior is characterized by irregular wave-like activity in neighboring patches of chromatophores, and the resulting patterns mimic reflections of down-welled light in the water column, suggesting that this behavior may provide a dynamic type of camouflage. Rapid and global pauses in flickering, often before a flashing episode, indicate that flickering is under inhibitory neural control. Although flashing and flickering have not been described in other squid, functional similarities are evident with other species.

  13. Controlled and in situ target strengths of the jumbo squid Dosidicus gigas and identification of potential acoustic scattering sources.

    PubMed

    Benoit-Bird, Kelly J; Gilly, William F; Au, Whitlow W L; Mate, Bruce

    2008-03-01

    This study presents the first target strength measurements of Dosidicus gigas, a large squid that is a key predator, a significant prey, and the target of an important fishery. Target strength of live, tethered squid was related to mantle length with values standardized to the length squared of -62.0, -67.4, -67.9, and -67.6 dB at 38, 70, 120, and 200 kHz, respectively. There were relatively small differences in target strength between dorsal and anterior aspects and none between live and freshly dead squid. Potential scattering mechanisms in squid have been long debated. Here, the reproductive organs had little effect on squid target strength. These data support the hypothesis that the pen may be an important source of squid acoustic scattering. The beak, eyes, and arms, probably via the sucker rings, also play a role in acoustic scattering though their effects were small and frequency specific. An unexpected source of scattering was the cranium of the squid which provided a target strength nearly as high as that of the entire squid though the mechanism remains unclear. Our in situ measurements of the target strength of free-swimming squid support the use of the values presented here in D. gigas assessment studies.

  14. Identification of conserved proteins from diverse shell matrix proteome in Crassostrea gigas: characterization of genetic bases regulating shell formation

    PubMed Central

    Feng, Dandan; Li, Qi; Yu, Hong; Kong, Lingfeng; Du, Shaojun

    2017-01-01

    The calcifying shell is an excellent model for studying biomineralization and evolution. However, the molecular mechanisms of shell formation are only beginning to be elucidated in Mollusca. It is known that shell matrix proteins (SMPs) play important roles in shell formation. With increasing data of shell matrix proteomes from various species, we carried out a BLASTp bioinformatics analysis using the shell matrix proteome from Crassostrea gigas against 443 SMPs from nine other species. The highly conserved tyrosinase and chitin related proteins were identified in bivalve. In addition, the relatively conserved proteins containing domains of carbonic anhydrase, Sushi, Von Willebrand factor type A, and chitin binding, were identified from all the ten species. Moreover, 25 genes encoding SMPs were annotated and characterized that are involved in CaCO3 crystallization and represent chitin related or ECM related proteins. Together, data from these analyses provide new knowledge underlying the molecular mechanism of shell formation in C.gigas, supporting a refined shell formation model including chitin and ECM-related proteins. PMID:28374770

  15. Indoor optical wireless communication: a GigaEthernet network prototype at 60 dB link margin

    NASA Astrophysics Data System (ADS)

    Bouchet, Olivier; Launay, Gilles; Besnard, Pascal

    2009-08-01

    The optical wireless system is a promising solution for increasing the available communication bandwidth within a room. This technology can give a very high-speed communication between devices and becomes a good alternative with respect to radio systems. For both technologies, the architecture is similar: a base station is installed to cover zones and transmit data with a defined quality of service. A device may be connected to the Wireless Local Area Network (WLAN) with an adapter that emits and receives on this network. The wireless optical technology has advantageous specific characteristics, such as: secure data transmission, immunity, high data rate, wavelength re-use. Nevertheless, the optical system may have a limit on the network management aspect and link budget. The scope of this paper is to present a prototype developed during a collaborative project. This prototype uses a Giga Ethernet chip and components in the 1550 nm band. Based on OOK modulation, the prototype is fully compatible with the direct conversion of fibre-based Giga-Ethernet to an analogue free space version. Moreover, it also proposes a new class 1 high power emission solution with 30 dBm on 45° HP (Half Power) angle and a new large Field Of View (FOV) module on the reception side. This full duplex system, composed by one Base station and two Modules, transmits data on, at least, one meter. The document will present the prototype characteristics with testbed and experimentation results.

  16. Structural studies on Desulfovibrio gigas cytochrome c3 by two-dimensional 1H-nuclear-magnetic-resonance spectroscopy.

    PubMed

    Piçarra-Pereira, M A; Turner, D L; LeGall, J; Xavier, A V

    1993-09-15

    Several aromatic amino acid residues and haem resonances in the fully reduced form of Desulfovibrio gigas cytochrome c3 are assigned, using two-dimensional 1H n.m.r., on the basis of the interactions between the protons of the aromatic amino acids and the haem protons as well as the intrahaem distances known from the X-ray structure [Kissinger (1989) Ph.D. Thesis, Washington State University]. The interhaem interactions observed in the n.m.r. spectra are in full agreement with the D. gigas X-ray structure and also with the n.m.r. data from Desulfovibrio vulgaris (Hildenborough) [Turner, Salgueiro, LeGall and Xavier (1992) Eur. J. Biochem. 210, 931-936]. The good correlation between the calculated ring-current shifts and the observed chemical shifts strongly supports the present assignments. Observation of the two-dimensional nuclear-Overhauser-enhancement spectra of the protein in the reduced, intermediate and fully oxidized stages led to the ordering of the haems in terms of their midpoint redox potentials and their identification in the X-ray structure. The first haem to oxidize is haem I, followed by haems II, III and IV, numbered according to the Cys ligand positions in the amino acid sequences [Mathews (1985) Prog. Biophys. Mol. Biol. 54, 1-56]. Although the haem core architecture is the same for the different Desulfovibrio cytochromes c3, the order of redox potentials is different.

  17. Impacts of ocean acidification on gene expression and biomineralisation in the Pacific oyster Crassostrea gigas Thunberg, 1793

    NASA Astrophysics Data System (ADS)

    Bagusche, F.; Pouvreau, S.; Trueman, C.; Long, S.; Hauton, C.

    2012-04-01

    The published evidence of impacts of ocean acidification and on marine calcifiers has emphasized the need to understand the molecular mechanisms of biomineralisation. Crassostrea gigas is an ideal organism to examine these processes as: 1) the hatchery rearing of larval stages is well constrained, 2) studies have established an ontogenetic switch in deposition of carbonate polymorphs from aragonite in larval shells to calcite in adults and 3) it is a globally-important commercial species. Research summarized in this presentation will identify some of the molecular mechanisms involved in calcification processes during ontogeny of Crassostrea gigas, as well as possible impacts of changes in environmental conditions such as temperature and pH. Data will be presented from a quantitative real-time PCR study of the changes in gene expression during development in different environments. Additionally scanning electron microscopy and infrared spectroscopy analyses of shell microstructures and composition will be summarised to correlate changes in gene expression with end-point differences in shell structure. Preliminary results suggest that changes in the environmental conditions lead to differences in expression patterns of genes involved in biomineralisation processes. The combined effects of ambient seawater temperature and low pH show the greatest negative effect on larval shell development, identified as malformations, eroded shell surfaces and a significant decrease in shell size. However, the effect of higher seawater temperature seems to amend the effects of ocean acidification on larval shell development.

  18. Genetic Variation and Breeding Signature in Mass Selection Lines of the Pacific Oyster (Crassostrea gigas) Assessed by SNP Markers

    PubMed Central

    Zhong, Xiaoxiao; Feng, Dandan; Yu, Hong; Kong, Lingfeng; Li, Qi

    2016-01-01

    In breeding industries, a challenging problem is how to keep genetic diversity over generations. To investigate genetic variation and identify breeding signatures in mass selected lines of Pacific oyster (Crassostrea gigas), three sixth-generation selected lines and four wild populations were assessed using 103 single nucleotide polymorphism (SNP) markers. The genetic diversity data indicated that the selected lines exhibited a significant reduction in the observed heterozygosity and observed number of alleles per locus compared with the wild populations (P≤0.05), indicating the selected lines tended to lose genetic diversity contrasted with the wild populations. The unweighted pair-group method with arithmetic mean (UPGMA) analysis showed that the wild populations and selected lines were not separated into two groups. Using four outlier tests, a total of 17 loci were found under selection at two levels. The global outlier detection suggested that 4 common outlier loci were subject to selection using both the hierarchical island model and Bayesian likelihood approaches. At regional level, 3 SNPs were detected as outlier using at least two outlier tests and one outlier SNP (CgSNP309) was overlapped in the two wild-selected population comparisons. The candidate outlier SNPs provide valuable resources for future association studies in C. gigas. PMID:26954577

  19. High pressure treatment changes spoilage characteristics and shelf life of Pacific oysters ( Crassostrea gigas) during refrigerated storage

    NASA Astrophysics Data System (ADS)

    Cao, Rong; Zhao, Ling; Liu, Qi

    2017-04-01

    The effects of high pressure (HP) treatment on spoilage characteristic and shelf life extension of Pacific oysters ( Crassostrea gigas) during refrigerated storage were studied. Results showed that HP treatment of 275 MPa for 3 min or 300 MPa for 2 min could achieve 100% full release of oyster adductor muscle, pressures higher than 350 MPa caused excessive release as the shells of oysters were broken, thus use of higher pressures should be cautious in oyster processing industry because of its adverse impact on the appearance of shells. HP treatment (300 MPa, 2 min) was proper for the shucking of Pacific oyster ( Crassostrea gigas) in China. This treatment caused no organoleptic disadvantage. Moreover, HP treatment resulted in obvious differences in biochemical spoilage indicators (pH, TVB-N and TBARS) changes and volatile compounds profile determined by electronic nose during storage. HP treatment (300 MPa, 2 min) also led to a reduction of aerobic bacterial count (APC) by 1.27 log cycles. Furthermore, the APC values of oysters treated by HP were always lower than those of the control samples during storage. Based on the organoleptic, biochemical and microbiological indicators, shelf life of 6-8 d for control and 12 d for HP-treated oysters could be expected. HP treatment showed great potential in oyster processing and preservation.

  20. Technical Raster Transfer Installation Drawing: Waveguide LPCR-130-2 Radar. Submitted By: Lockheed Aeronautical Systems. Supporting: WR-ALC/TILCA’s EDCARS Program Contract Number F33657-90-C-0071-P000l3BL2. MIL-STD-1840A, MIL-R-28002A (Raster). Quick Short Test Report.

    DTIC Science & Technology

    2007-11-02

    0002600 del del del del del del del del del del del del del del e gs 0002620 M dc4 "dc4bs be. nl [ % d #em v a 9 AFCTN Test Report AFCTB Test Report 94-110...94-106 0002640 dcl c bs so d q dcl Q gs dcl b # etx enq H 0002660 so bs a stx 8 g # D t G dc4 8 0 G dle so 0002700 d p S # soh h @ ( . bel I bs dle 8

  1. Fetal programming of adult Leydig cell function by androgenic effects on stem/progenitor cells.

    PubMed

    Kilcoyne, Karen R; Smith, Lee B; Atanassova, Nina; Macpherson, Sheila; McKinnell, Chris; van den Driesche, Sander; Jobling, Matthew S; Chambers, Thomas J G; De Gendt, Karel; Verhoeven, Guido; O'Hara, Laura; Platts, Sophie; Renato de Franca, Luiz; Lara, Nathália L M; Anderson, Richard A; Sharpe, Richard M

    2014-05-06

    Fetal growth plays a role in programming of adult cardiometabolic disorders, which in men, are associated with lowered testosterone levels. Fetal growth and fetal androgen exposure can also predetermine testosterone levels in men, although how is unknown, because the adult Leydig cells (ALCs) that produce testosterone do not differentiate until puberty. To explain this conundrum, we hypothesized that stem cells for ALCs must be present in the fetal testis and might be susceptible to programming by fetal androgen exposure during masculinization. To address this hypothesis, we used ALC ablation/regeneration to identify that, in rats, ALCs derive from stem/progenitor cells that express chicken ovalbumin upstream promoter transcription factor II. These stem cells are abundant in the fetal testis of humans and rodents, and lineage tracing in mice shows that they develop into ALCs. The stem cells also express androgen receptors (ARs). Reduction in fetal androgen action through AR KO in mice or dibutyl phthalate (DBP) -induced reduction in intratesticular testosterone in rats reduced ALC stem cell number by ∼40% at birth to adulthood and induced compensated ALC failure (low/normal testosterone and elevated luteinizing hormone). In DBP-exposed males, this failure was probably explained by reduced testicular steroidogenic acute regulatory protein expression, which is associated with increased histone methylation (H3K27me3) in the proximal promoter. Accordingly, ALCs and ALC stem cells immunoexpressed increased H3K27me3, a change that was also evident in ALC stem cells in fetal testes. These studies highlight how a key component of male reproductive development can fundamentally reprogram adult hormone production (through an epigenetic change), which might affect lifetime disease risk.

  2. Molecular Characterization and Functional Analysis of a Putative Octopamine/Tyramine Receptor during the Developmental Stages of the Pacific Oyster, Crassostrea gigas

    PubMed Central

    Ji, Peng; Xu, Fei; Huang, Baoyu; Li, Yingxiang; Li, Li; Zhang, Guofan

    2016-01-01

    Octopamine (OA) and its precursor, tyramine (TA), participate in invertebrate development such as growth, maturation, and reproduction by activating their corresponding G protein-coupled receptors (GPCRs). Although OA was first discovered in mollusks (octopus), subsequent studies on OA, TA and related receptors have primarily been conducted in Ecdysozoa, especially in insects. Accordingly, only limited reports on OA/TA receptors in mollusks are available and their physiological roles remain unclear. Here, a full-length cDNA encoding a putative 524 amino acid OA/TA receptor (CgGPR1) was isolated from the Pacific oyster Crassostrea gigas. CgGPR1 was most closely related to the Lymnaea stagnalis OA receptor OAR2 in sequence. Phylogenetic analysis showed that CgGPR1 belongs to a poorly studied subfamily of invertebrate OA/TA receptors. The spatio-temporal expression of CgGPR1 in C. gigas larvae was examined by quantitative real-time PCR and Western blot analysis. CgGPR1 was expressed during all developmental stages of C. gigas with higher levels at mid-developmental stages, indicating its potential role in embryogenesis and tissue differentiation. Immunoreactive fluorescence of CgGPR1 was mainly observed in the velum, foot, gill and mantle of C. gigas larvae. CgGPR1 transcripts were detected in all the tested organs of adult C. gigas, with highest level in the mantle. Pharmacological analysis showed that cAMP and Ca2+ concentrations remained unchanged in HEK293 cells expressing CgGPR1 upon addition of OA, TA or related amines, suggesting that CgGPR1 modulates other unknown molecules rather than cAMP and Ca2+. Our study sheds light on CgGPR1 function in oysters. PMID:27992549

  3. Mortality and herpesvirus infections of the Pacific oyster Crassostrea gigas in Tomales Bay, California, USA.

    PubMed

    Burge, Colleen A; Griffin, Frederick J; Friedman, Carolyn S

    2006-09-14

    Seed losses of Pacific oysters Crassostrea gigas have been associated with an ostreid herpesvirus-1 (OsHV-1) in Europe, and in 2002, a similar OsHV was detected in Tomales Bay, California, USA. In May of 2003, 5 stocks of seed Pacific oysters were planted at 2 sites (Inner Bay and Outer Bay) in Tomales Bay and monitored for mortality, presence/prevalence of OsHV (using polymerase chain reaction [PCR] and histology), and growth. Temperature (degrees C) and salinity data were collected every half an hour at each site. OsHV was detected at both the Inner and Outer Bay sites on the same sample date and mean temperature predicted OsHV presence (p < 0.005). High levels of mortality occurred 2 wk (Inner Bay site) and 4 wk (Outer Bay site) after OsHV detection. OsHV presence predicted mortality (p = 0.01). Temperature maximums and overall temperature exposure were greater at the Inner Bay site and may explain why mortality affected these oysters sooner than oysters planted at the Outer Bay site. Differences in cumulative mortality were significant among stocks (p < 0.0001), but not between sites (p > 0.05). OsHV prevalence was similar among stocks (p > 0.05) and between sites (p > 0.05). No evidence of herpesvirus-induced Cowdry type A nuclear inclusions or other pathogens were observed. Changes in tissue and cellular architecture including dilation of the digestive tubules and nuclear chromatin margination and pycnosis were observed in OsHV-infected oysters, consistent with previously observed OsHV infections. Stocks with smaller oysters had higher mortality rates than those with larger oysters; growth rate did not correlate with mortalities (p > 0.05). Taken together, these data suggest that the OsHV may cause or act in synergy with temperature to kill Pacific oyster seed in Tomales Bay, but further investigation of OsHV etiology in seed oysters is needed.

  4. Detection of undescribed ostreid herpesvirus 1 (OsHV-1) specimens from Pacific oyster, Crassostrea gigas.

    PubMed

    Martenot, Claire; Lethuillier, Ophélie; Fourour, Sarah; Oden, Elise; Trancart, Suzanne; Travaillé, Emmanuelle; Houssin, Maryline

    2015-11-01

    The ostreid herpesvirus 1 (OsHV-1) and variants were implicated in mass mortality affecting the young Pacific cupped oysters, Crassostrea gigas, in European countries and those around the world. From 2008 onwards, oyster mortality had greatly increased on the French coast and was associated with the detection of a new OsHV-1 variant, entitled OsHV-1 μVar. The OsHV-1 μVar is predominant in oysters; however, other OsHV-1 variants have been detected in samples collected during mortality periods or collected out of mortality periods in France, Ireland, Spain, Portugal, Italy, Mexico, United States, South Korea, Australia, and New Zealand. A retrospective study conducted on 1047 OsHV-1 specimens sampled mainly in France between 2009 and 2012, revealed 17 undescribed OsHV-1 variants found in 65 oyster samples. These specimens presented point mutations situated downstream and upstream from the microsatellite area in the C region (ORF 4/5) which were different from the OsHV-1 reference and the OsHV-1 μVar. In the present work, investigation was performed to further characterize these OsHV-1 specimens by sequencing two habitually targeted regions to study genetic polymorphism of the virus: ORF 41/42 and ORF 35-38. An OsHV-1 variant detected in six oyster samples, contained a nucleotide substitution in the C region which impacted the amino acid sequence and might modify the function of the unknown protein encoding by ORF 4. For the ORF 41/42 region, only two specimens presented a synonymous mutation in comparison with the OsHV-1 μVar. All specimens contained the same deletion with the OsHV-1 μVar in ORF 35-38. Then, a phylogenetic analysis based on the C region was performed to investigate the distribution of undescribed specimens among 21 OsHV-1 DNA sequences notified in GenBank and collected from different countries (France, Japan, New Zealand, China, Ireland, and United States) between 1995 and 2012. All analyzed samples and the OsHV-1 μVar were placed in the same

  5. Effects of natural oyster reefs (Crassostrea gigas) on the sediment balance of Oosterschelde tidal flats

    NASA Astrophysics Data System (ADS)

    Paiva, João; de Vries, Mindert

    2014-05-01

    The realization of the storm surge barrier and the two secondary dams not only changed the hydrodynamics, but also the geomorphological characteristics of the Oosterschelde estuary (SW Netherlands) creating a disequilibrium between erosion and sedimentation. This has lead in the last 25 years to a sand deficit in the Oosterschelde resulting in the erosion of the tidal flats (Smaal & Nienhuis, 1992; Nienhuis & Smaal 1994). Due to these phenomena the habitat for intertidal soft-bottom benthic fauna is slowly disappearing, and with it food sources for estuarine birds that use these areas as foraging grounds (Mulder & Louters, 1994). Erosion of tidal flats also locally exposes deeper peat layers, potentially resulting in reduced water clarity and primary production (Nienhuis & Smaal 1994). Adding to these problems an increased risk of dike failures and flooding during storm surges is expected, as the dikes gradually become more exposed to wave action. In this research the effect of oysters (Crassostrea gigas) as ecosystem engineers, on the sediment balance in the Oosterschelde was studied. In our analysis we compared long term bathymetry data for transects with and without oyster reefs. Based on height differences, the transects sedimentation/erosion rates were calculated and used to determine if there was a difference between transects without oyster reefs and transects crossing oyster reefs. From the long term analysis, the overall erosional trend of the Oosterschelde tidal flats is clear. The mean observed erosion was - 0,012 m per year. When considering the sections crossing oyster reefs , a mean accumulation of sediment of + 0,007 m per year was observed. The results suggest that these ecosystem engineers, that cover large areas in the Oosterschelde slow down the erosion of the tidal flats in the Oosterschelde, as they act as sediment accumulators and stabilizers. We estimate at least 70000 m3 of sediment per year is accreted on tidal flats due to the effect of

  6. Vibrio sonorensis sp. nov. isolated from a cultured oyster Crassostrea gigas.

    PubMed

    González-Castillo, Adrián; Enciso-Ibarra, Julissa; Dubert, Javier; Romalde, Jesús L; Gomez-Gil, Bruno

    2016-11-01

    Strain CAIM 1076(T) was isolated from a cultured oyster Crassostrea gigas in Puerto Peñasco, Sonora state, México. The strain was taxonomically characterised by means of a genomic approach, comprising 16S rRNA gene sequence analysis, multilocus sequence analysis (MLSA), the DNA G+C content and whole genome analyses (ANI and GGDC), and by phenotypic characterisation. Strain CAIM 1076(T) was found to be catalase and oxidase positive, and cells were observed to be motile and facultative anaerobic. Analysis of the almost-complete 16S rRNA gene sequence placed this strain within the genus Vibrio; closely related species were Vibrio maritimus, Vibrio variabilis, Vibrio proteolyticus, and Vibrio nigripulchritudo with similarity values of 98.9, 98.5, 98.1, and 98.0 %, respectively. MLSA of six housekeeping genes (ftsZ, gapA, gyrB, recA, rpoA and topA) was performed with the closely related species. A draft genome sequence of strain CAIM 1076(T) was obtained. The DNA G+C content of this strain was determined to be 44.5 mol %. The genomic similarity values with V. maritimus were 71.6 % (ANIb), 85.1 % (ANIm) and a GGDC value of 20.3 ± 2.3 %; with V. variabilis the genomic similarities were 71.8 % (ANIb), 85.4 % (ANIm) and 20.0 ± 2.3 % (GGDC); with V. proteolyticus, 71.6 % (ANIb), 84.1 % (ANIm) and 18.8 ± 2.2 % (GGDC); and with V. nigripulchritudo, 70.8 % (ANIb), 84.9 % (ANIm) and 20.5 ± 2.3 % (GGDC). These ANI and GGDC values are below the thresholds for the delimitation of prokaryotic species, i.e., 95-96 and 70 %, respectively. Phenotypic characters also showed differences with the closely related species analysed. The results presented here support the description of a novel species, for which the name Vibrio sonorensis sp. nov. is proposed, with strain CAIM 1076(T) (=CECT 9100(T), =DSM 102190(T)) as the type strain.

  7. The immunological capacity in the larvae of Pacific oyster Crassostrea gigas.

    PubMed

    Song, Xiaorui; Wang, Hao; Xin, Lusheng; Xu, Jiachao; Jia, Zhihao; Wang, Lingling; Song, Linsheng

    2016-02-01

    As the immune system has not fully developed during early developmental stages, bivalve larvae are more susceptible for pathogens, which frequently leads to the significant mortality in hatcheries. In the present study, the development of immune system and its response against bacteria challenge were investigated in order to characterize the repertoire of immunological capacity of Pacific oyster Crassostrea gigas during the ontogenesis. The phagocytosis was firstly observed in the early D-veliger larvae (17 hpf), especially in their velum site, which indicated the appearance of functional hemocytes during early D-veliger larvae stage. The whole-mount immunofluorescence assay of three pattern recognition receptors (integrin β-1, caspase-3 and C-type lectin 3) and one immune effector gene (IL17-5) was performed in blastula, early D-veliger and umbo larvae, suggested that velum and digestive gland were the potential sites of immune system in the larvae. The lowest activities of antioxidant enzymes (superoxide dismutase and catalase) and hydrolytic enzyme (lysozyme), as well as descended expression levels of 12 immune genes at the transition between embryogenesis and planktonic, indicated that the larvae at hatching (9 hpf) were in hypo-immunity. While the ascending activities of enzymes and expression levels of seven immune genes during the trochophore stage (15 hpf) suggested the initiation of immune system. The steadily increasing trend of all the 12 candidate genes at the early umbo larvae (120 h) hinted that the immune system was well developed at this stage. After bacterial challenge, some immune recognition (TLR4) and immune effector (IL17-5 and defh2) genes were activated in blastula stage (4 hpf), and other immune genes were up regulated in D-veliger larvae, indicating that the zygotic immune system could respond earlier against the bacterial challenge during its development. These results indicated that the cellular and humoral immune components

  8. The X-ray view of giga-hertz peaked spectrum radio galaxies

    NASA Astrophysics Data System (ADS)

    Tengstrand, O.; Guainazzi, M.; Siemiginowska, A.; Fonseca Bonilla, N.; Labiano, A.; Worrall, D. M.; Grandi, P.; Piconcelli, E.

    2009-07-01

    Context: This paper presents the X-ray properties of a flux- and volume-limited complete sample of 16 giga-hertz peaked spectrum (GPS) galaxies. Aims: This study addresses three basic questions in our understanding of the nature and evolution of GPS sources: a) What is the physical origin of the X-ray emission in GPS galaxies? b) Which physical system is associated with the X-ray obscuration? c) What is the “endpoint” of the evolution of compact radio sources? Methods: We discuss in this paper the results of the X-ray spectral analysis, and compare the X-ray properties of the sample sources with radio observables. Results: We obtain a 100% (94%) detection fraction in the 0.5-2 keV (0.5-10 keV) energy band. GPS galaxy X-ray spectra are typically highly obscured (< N_HGPS > = 3 × 1022 cm-2; σN_H ≃ 0.5 dex). The X-ray column density is larger than the HI column density measured in the radio by a factor 10 to 100. GPS galaxies lie well on the extrapolation to high radio powers of the correlation between radio and X-ray luminosity known in low-luminosity FR I radio galaxies. On the other hand, GPS galaxies exhibit a comparable X-ray luminosity to FR II radio galaxies, notwithstanding their much larger radio luminosity. Conclusions: The X-ray to radio luminosity ratio distribution in our sample is consistent with the bulk of the high-energy emission being produced by the accretion disk, as well as with dynamical models of GPS evolution where X-rays are produced by Compton upscattering of ambient photons. Further support to the former scenario comes from the location of GPS galaxies in the X-ray to O[iii] luminosity ratio versus NH plane. We propose that GPS galaxies are young radio sources, which would reach their full maturity as classical FR II radio galaxies. However, column densities ≳ 1022 cm-2 could lead to a significant underestimate of dynamical age determinations based on the hotspot recession velocity measurements.

  9. Characterizations of Shell and Mantle Edge Pigmentation of a Pacific Oyster, Crassostrea gigas, in Korean Peninsula.

    PubMed

    Kang, Jung-Ha; Kang, Hyun-Sook; Lee, Jung-Mee; An, Chel-Min; Kim, Sung-Youn; Lee, Yun-Mi; Kim, Jong-Joo

    2013-12-01

    The objectives of this study were to investigate color patterns of shell and mantle edge pigmentation of a Pacific oyster, C. gigas, and to estimate variance components of the two colors. A sample of 240 F0 oysters was collected from six aquaculture farms in Tongyeong, Korea to measure shell color and mantle edge pigmentation. Among the F0s, male and female individuals with black (white) shell and black (white) mantle edge were selected and mated to generate three F1 full-sib black (white) cross families (N = 265). Two and four F2 cross families (N = 286) were also produced from black and white F1 selected individuals, respectively. Variance component estimates due to residuals and families within color were obtained using SAS PROC VARCOMP procedures to estimate heritability of shell and mantle edge pigmentation. In the F0 generation, about 29% (11%) had black (white) color for both shell and mantle edge. However, in the F1 and F2 black (white) cross families, 75% (67%) and 100% (100%) of oysters had black (white) shell colors, and 59% (23%) and 79% (55%) had black (white) mantle edge, respectively. Spearman correlation coefficients between shell and mantle edge color were 0.25, 0.74, and 0.92 in F0, F1, and F2 generations, respectively, indicating that, with generations of selection process, an individual with black (white) shell color is more likely to have black (white) mantle edge pigmentation. This suggests that shell color could be a good indicator trait for mantle edge pigmentation if selection of both the colors is implemented for a couple of generations. Estimates of heritability were 0.41 and 0.77 for shell color and 0.27 and 0.08 for mantle edge pigmentation in the F1 and F2 generations, respectively, indicating that, in general, significant proportions of phenotypic variations for the shell and mantle edge colors are explained by genetic variations between individuals. These results suggest that the two color traits are inheritable and correlated

  10. The raised coral reef complex of the Kenyan coast: Tridacna gigas U-series dates and geological implications

    NASA Astrophysics Data System (ADS)

    Accordi, Giovanni; Brilli, Mauro; Carbone, Federico; Voltaggio, Mario

    2010-08-01

    The Kenyan coast is characterized by a raised fossil reef complex cut by a series of morphological terraces. Shallow subtidal coralgal facies containing Tridacna gigas shells are found at different heights along the coast. Alpha-spectrometric U-series methods were applied to 18 T. gigas samples from different locations along this reef complex with an elevation range from 0 to 15 m above present sea level to obtain chronological information. Apparent U-Th ages, based on the assumption of closed system behaviour, correspond to early marine isotope stage (MIS) 5 ( n = 17) and MIS 7 ( n = 1). However, initial 234U/ 238U activity ratios exhibit a wide range, in many cases much greater than present seawater, which is likely to be associated with diagenetic alteration and migration of U-series isotopes. For this reason, we attempted a form of open system isochron dating after separating the Tridacna samples into three different groups on the basis of current elevation and distribution along the coast. An 'isochron' age of 120 ± 4 ka (1 σ) was obtained for the higher elevation group, placed in the terraced central coastal area; another age, statistically undistinguishable from the previous one, of 118 ± 7 ka (1 σ) was obtained for the group confined along the northern coast. These two groups correspond to a transgressive-regressive cycle connected to the maximum sea level highstand during the MIS 5e. A third 'isochron' age of 100 ± 4 ka (1 σ) was obtained for the group confined along the southern coast, encompassing part of the isotopic substages MIS 5c and d. Based on these data, and on the ecology of T. gigas whose optimal present-day depth range can be considered of 3-10 m below sea level, a maximum tectonic coastal uplift rate of between, respectively, 0.12 and 0.18 mm a -1 was calculated for the period since formation of these shells, and then the paleobathymetry of Tridacna facies has been inferred.

  11. Effects of Dietary Alpha-lipoic Acid and Acetyl-L-carnitine on Growth Performance and Meat Quality in Arbor Acres Broilers.

    PubMed

    Zhang, Yong; Jia, Ru; Ji, Cheng; Ma, Qiugang; Huang, Jin; Yin, Haicheng; Liu, Laiting

    2014-07-01

    An experiment was conducted to evaluate the effects of dietary alpha-lipoic acid (LA) and acetyl-L-carnitine (ALC) on growth performance, carcass characteristics and meat quality in Arbor Acres broilers. A total of 486 1-d-old male Arbor Acres broilers were randomly allocated to 9 dietary treatments, 9 treatments were group A (0 mg/kg LA and 0 mg/kg ALC), group B (50 mg/kg LA and 0 mg/kg ALC), group C (100 mg/kg LA and 0 mg/kg ALC), group D (0 mg/kg LA and 50 mg/kg ALC), group E (50 mg/kg LA and 50 mg/kg ALC), group F (100 mg/kg LA and 50 mg/kg ALC), group G (0 mg/kg LA and 100 mg/kg ALC), group H (50 mg/kg LA and 100 mg/kg ALC), group I (100 mg/kg LA and 100 mg/kg ALC). Birds were slaughtered at 42 days old. Average daily gain (ADG), average feed intake (AFI), feed conversion rate (FCR), eviscerated rate, breast muscle percentage, thigh muscle percentage, abdominal fat percentage, liver weight, muscle color (L* value, a* value, b* value), pH values at 45 min and 24 h postmortem were measured. Results showed that there existed an interaction between LA and ALC in growth performance of broilers, carcass traits and meat quality. The overall result is that high level of LA and ALC led to lower AFI, ADG (p<0.01), lower abdominal fat percentage, liver weight (p<0.01), lower L* value, a* value, and b* value of breast muscle, L* value of thigh muscle (p<0.05), and higher FCR (p<0.01), eviscerated rate (p<0.01), breast muscle percentage, thigh muscle percentage (p<0.05), a* value, pH 45 min and pH 24 h of thigh muscle (p<0.01). These results suggested that dietary LA and ALC contributed to the improvement of meat quality in broilers.

  12. Absolute lymphocyte count recovery after allogeneic hematopoietic stem cell transplantation predicts clinical outcome.

    PubMed

    Kim, Haesook T; Armand, Philippe; Frederick, David; Andler, Emily; Cutler, Corey; Koreth, John; Alyea, Edwin P; Antin, Joseph H; Soiffer, Robert J; Ritz, Jerome; Ho, Vincent T

    2015-05-01

    Immune reconstitution is critical for clinical outcome after allogeneic hematopoietic stem cell transplantation (HSCT). To determine the impact of absolute lymphocyte count (ALC) recovery on clinical outcomes, we conducted a retrospective study of 1109 adult patients who underwent a first allogeneic HSCT from 2003 through 2009, excluding patients who died or relapsed before day 30. The median age was 51 years (range, 18 to 74) with 52% undergoing reduced-intensity conditioning and 48% undergoing myeloablative conditioning HSCT with T cell-replete peripheral blood stem cells (93.7%) or marrow (6.4%) grafts. The median follow-up time was 6 years. To determine the threshold value of ALC for survival, the entire cohort was randomly split into a training set and a validation set in a 1:1 ratio, and then a restricted cubic spline smoothing method was applied to obtain relative hazard estimates of the relationship between ALC at 1 month and log hazard of progression-free survival (PFS). Based on this approach, ALC was categorized as ≤.2 × 10(9) cells/L (low) or >.2 × 10(9) cells/L. For patients with low ALC at 1, 2, or 3 months after HSCT, the overall survival (OS) (P ≤ .0001) and PFS (P ≤ .0002) were significantly lower and nonrelapse mortality (NRM) (P ≤ .002) was significantly higher compared with patients with ALC > .2 × 10(9) cells/L at each time point. When patients who had low ALC at 1, 2, or 3 months after HSCT were grouped together and compared, their outcomes were inferior to those of patients who had ALC > .2 × 10(9) cells/L at 1, 2, and 3 months after HSCT: the 5-year OS for patients with low ALC was 28% versus 46% for patients with ALC > .2 × 10(9) cells/L, P < .0001; the 5-year PFS was 21% versus 39%, P < .0001, respectively and 5-year NRM was 40% versus 18%, P < .0001, respectively. This result remained consistent when other prognostic factors, including occurrence of grade II to IV acute graft-versus-host disease (GVHD), were adjusted for in

  13. Effect of prenatal alcohol exposure on bony craniofacial development: a mouse MicroCT study.

    PubMed

    Shen, Li; Ai, Huisi; Liang, Yun; Ren, Xiaowei; Anthony, Charles Bruce; Goodlett, Charles R; Ward, Richard; Zhou, Feng C

    2013-08-01

    Craniofacial bone dysmorphology is an important but under-explored potential diagnostic feature of fetal alcohol spectrum disorders. This study used longitudinal MicroCT 3D imaging to examine the effect of prenatal alcohol exposure on craniofacial bone growth in a mouse model. C57BL/6J dams were divided into 3 groups: alcohol 4.2% v/v in PMI® liquid diet (ALC), 2 weeks prior to and during pregnancy from embryonic (E) days 7-E16; pair-fed controls (PF), isocalorically matched to the ALC group; chow controls (CHOW), given ad libitum chow and water. The MicroCT scans were performed on pups on postnatal days 7 (P7) and P21. The volumes of the neurocranium (volume encased by the frontal, parietal, and occipital bones) and the viscerocranium (volume encased by the mandible and nasal bone), along with total skull bone volume, head size, and head circumference were evaluated using general linear models and discriminant analyses. The pups in the alcohol-treated group, when compared to the chow-fed controls (ALC vs CHOW) and the isocaloric-fed controls (ALC vs PF), showed differences in head size and circumference at P7 and P21, the total skull volume and parietal bone volume at P7, and volume of all the tested bones except nasal at P21. There was a growth trend of ALC < CHOW and ALC < PF. While covarying for gender and head size or circumference, the treatment affected the total skull and mandible at P7 (ALC > CHOW), and the total skull, parietal bone, and occipital bone at P21 (ALC < CHOW, ALC < PF). While covarying for the P7 measures, the treatment affected only the 3 neurocranial bones at P21 (ALC < CHOW, ALC < PF). Discriminant analysis sensitively selected between ALC and CHOW (AUC = 0.967), between ALC and PF (AUC = 0.995), and between PF and CHOW (AUC = 0.805). These results supported our hypothesis that craniofacial bones might be a reliable and sensitive indicator for the diagnosis of prenatal alcohol exposure. Significantly, we found that the neurocranium (upper

  14. Interactive effects of chronic cigarette smoking and age on brain volumes in controls and alcohol-dependent individuals in early abstinence.

    PubMed

    Durazzo, Timothy C; Mon, Anderson; Pennington, David; Abé, Christoph; Gazdzinski, Stefan; Meyerhoff, Dieter J

    2014-01-01

    Chronic alcohol-use disorders (AUDs) have been shown to interact with normal age-related volume loss to exacerbate brain atrophy with increasing age. However, chronic cigarette smoking, a highly co-morbid condition in AUD and its influence on age-related brain atrophy have not been evaluated. We performed 1.5 T quantitative magnetic resonance imaging in non-smoking controls [non-smoking light drinking controls (nsCONs); n = 54], smoking light drinking controls (sCONs, n = 34), and one-week abstinent, treatment-seeking alcohol-dependent (ALC) non-smokers (nsALCs, n = 35) and smokers (sALCs, n = 43), to evaluate the independent and interactive effects of alcohol dependence and chronic smoking on regional cortical and subcortical brain volumes, emphasizing the brain reward/executive oversight system (BREOS). The nsCONs and sALCs showed greater age-related volume losses than the nsALCs in the dorsal prefrontal cortex (DPFC), total cortical BREOS, superior parietal lobule and putamen. The nsALCs and sALCs demonstrated smaller volumes than the nsCONs in most cortical region of interests (ROIs). The sCONs had smaller volumes than the nsCONs in the DPFC, insula, inferior parietal lobule, temporal pole/parahippocampal region and all global cortical measures. The nsALCs and sALCs had smaller volumes than the sCONs in the DPFC, superior temporal gyrus, inferior and superior parietal lobules, precuneus and all global cortical measures. Volume differences between the nsALCs and sALCs were observed only in the putamen. Alcohol consumption measures were not related to volumes in any ROI for ALC; smoking severity measures were related to corpus callosum volume in the sCONs and sALCs. The findings indicate that consideration of smoking status is necessary for a better understanding of the factors contributing to regional brain atrophy in AUD.

  15. Comparison of haemocytic parameters among flat oyster Ostrea edulis stocks with different susceptibility to bonamiosis and the Pacific oyster Crassostrea gigas.

    PubMed

    Comesaña, Pilar; Casas, Sandra M; Cao, Asunción; Abollo, Elvira; Arzul, Isabelle; Morga, Benjamin; Villalba, Antonio

    2012-03-01

    Farming of the flat oyster Ostrea edulis in Europe is severely constrained by the protozoan Bonamia ostreae. The introduction of the resistant species Crassostrea gigas has been a relief for the farmers, while the pilot programmes to select O. edulis strains resistant to bonamiosis performed in various countries can be seen as a promising strategy to minimise the effects of bonamiosis. However, the physiological bases of this differential susceptibility remain unknown. A search for an explanation of the intra and interspecific differences in oyster susceptibility to bonamiosis was accomplished by comparing some immune parameters among various O. edulis stocks and C. gigas. On December 2003, naïve and Bonamia-relatively resistant flat oysters from Ireland, Galician flat oysters and Pacific oysters C. gigas were deployed in a Galician area affected by bonamiosis; haemolymph samples were taken in February and May 2004. A new oyster deployment at the same place was carried out on June 2004 and haemolymph sampling was performed on April 2005. On November 2004, new sets of Irish flat oysters and C. gigas were deployed in Ireland and haemolymph sampling was performed in June 2005. Various haemocytic parameters were measured: total and differential haemocyte count, phagocytic ability, respiratory burst (superoxide anion [O(2)(-)] and hydrogen peroxide [H(2)O(2)]) and nitric oxide [NO] production. The comparison of the parameters was carried out at 3 levels: (1) between O. edulis and C. gigas, (2) among O. edulis stocks with different susceptibility to bonamiosis, and (3) between Bonamia-infected and non infected O. edulis. In addition, haemocyte-B. ostreaein vitro encounters were performed to analyse interspecific differences in the haemocytic respiratory burst, using flow cytometry. Significant differences associated with total and differential haemocyte count, and respiratory burst between O. edulis and C. gigas were detected, which could be linked to differences in

  16. Distribution of trace metals in the Pacific Oyster, Crassostrea gigas, and crabs from the east coast of Kyushu Island, Japan

    SciTech Connect

    Szefer, P.; Frelek, K.; Geldon, J.

    1997-01-01

    Oysters are known to be exceptional accumulators of Zn and Cu, and their tissue concentrations appear to reflect contamination of metals. According to Lauenstein and Dolvin, oysters clearly have a greater affinity for Ag, Cu and Zn than do mussels, while mussels have greater affinity for Cr and Pb. Oysters have been considered to be potential bioindicators for monitoring metallic pollution in marine environments. Extensive investigations of oysters from the east coast of Kyushu Island, Japan, have been performed. The aim of the study was to examine spatial differences in metal concentrations in soft tissues of the Pacific oyster (Crassostrea gigas) and whole bodies (soft tissues with shells) of the crabs Goetice depressa and Leptodius exaratus inhabiting the Japanese coastal region of the Pacific. 18 refs., 3 figs.

  17. Production and functional evaluation of a protein concentrate from giant squid (Dosidicus gigas) by acid dissolution and isoelectric precipitation.

    PubMed

    Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Elena Lugo-Sánchez, M; Gisela Carvallo-Ruiz, M; García-Sánchez, Guillermina

    2008-09-15

    A protein concentrate from giant squid (Dosidicus gigas) was produced under acidic conditions and its functional-technological capability evaluated in terms of its gel-forming ability, water holding capacity and colour attributes. Technological functionality of the concentrate was compared with that of squid muscle and a neutral concentrate. Protein-protein aggregates insoluble at high ionic strength (I=0.5M), were detected in the acidic concentrate as result of processing with no preclusion of its gel-forming ability during the sol-to-gel thermal transition. Even though washing under acidic condition promoted autolysis of the myosin heavy chain, the acidic concentrate displayed an outstanding ability to gel giving samples with a gel strength of 455 and 1160gcm at 75% and 90% compression respectively, and an AA folding test grade indicative of high gel strength, elasticity, and cohesiveness. The process proved to be a good alternative for obtaining a functional protein concentrate from giant squid muscle.

  18. Conformational changes in proteins recovered from jumbo squid (Dosidicus gigas) muscle through pH shift washing treatments.

    PubMed

    Cortés-Ruiz, Juan A; Pacheco-Aguilar, Ramón; Ramírez-Suárez, Juan C; Lugo-Sánchez, Maria E; García-Orozco, Karina D; Sotelo-Mundo, Rogerio R; Peña-Ramos, Aida

    2016-04-01

    Conformational and thermal-rheological properties of acidic (APC) and neutral (NPC) protein concentrates were evaluated and compared to those of squid (Dosidicus gigas) muscle proteins (SM). Surface hydrophobicity, sulfhydryl status, secondary structure profile, differential scanning calorimetry and oscillatory dynamic rheology were used to evaluate the effect of treatments on protein properties. Acidic condition during the washing process (APC) promoted structural and conformational changes in the protein present in the concentrate produced. These changes were enhanced during the heat setting of the corresponding sol. Results demonstrate that washing squid muscle under the proposed acidic conditions is a feasible technological alternative for squid-based surimi production improving its yield and gel-forming ability.

  19. Analysis of the tenderisation of jumbo squid (Dosidicus gigas) meat by ultrasonic treatment using response surface methodology.

    PubMed

    Hu, Yaqin; Yu, Hiaxia; Dong, Kaicheng; Yang, Shuibing; Ye, Xingqian; Chen, Shiguo

    2014-10-01

    Due to its unique structure, jumbo squid (Dosidicus gigas) meat is sensitive to heat treatment, which makes the traditional squid products taste tough and hard. This study aimed to tenderise jumbo squid meat through ultrasonic treatment. Response surface methodology (RSM) was used to predict the tenderising effect of various treatment conditions. According to the results of RSM, the optimal conditions appeared to be a power of 186.9 W, a frequency of 25.6 kHz, and a time of 30.8 min, and the predicted values of flexibility and firmness under these optimal conditions were 2.40 mm and 435.1 g, respectively. Protein degradation and a broken muscle fibre structure were observed through histological assay and SDS-PAGE, which suggests a satisfactory tenderisation effect.

  20. Description of plastic remains found in the stomach contents of the jumbo squid Dosidicus gigas landed in Ecuador during 2014.

    PubMed

    Rosas-Luis, Rigoberto

    2016-12-15

    Squids are active and opportunistic predators that feed on a wide range of prey. Their active movements in the water column and their voracity promote a high consumption of food. In the pelagic environment off Ecuador, marine pollution is characterized by plastic debris with a mainland origin, including plastics trash of fishing gears. The objective of this work was to describe the presence of plastic remains in the stomach contents of Dosidicus gigas caught off the coast of Ecuador. Results demonstrated that 12% of the stomachs contained plastic remains. These plastics were identified as multifilament of polyethylene lines and polyvinyl chloride remains. Findings of this work could be related to an increase in the discharge of solid materials in the water column, increasing the probability to be ingested by the jumbo squid.

  1. Heavy-metal accumulation in the hydrothermal vent clam Vesicomya gigas from Guaymas basin, Gulf of California

    NASA Astrophysics Data System (ADS)

    Ruelas-Inzunza, Jorge; Soto, Luis A.; Páez-Osuna, Federico

    2003-06-01

    This work provides data on the concentration and distribution of Cd, Cu, Fe, Hg, Mn, Pb and Zn in different tissues of the vent clam Vesicomya gigas. Twelve clams were collected from the Guaymas basin (Gulf of California) during the Extreme 2000 expedition (January 14-19, 2000) onboard the deep-sea research vehicle Alvin. Analysis of Hg was made by a mercury analyzer after reduction with SnCl 2; the rest of the metals were analyzed by atomic absorption spectrophotometry. The highest amounts (in μg g -1 dry weight) of Cd (115.2), Fe (403.2), Hg (4.96), Mn (18) and Zn (844.8) were detected in the gills; Cu (29.7) and Pb (3.67) occurred mainly in the mantle. In spite of the tremendous amounts of metals occurring in this species, no deleterious effects were recognizable.

  2. Changes in microbial flora of Pacific oysters (Crassostrea gigas) during refrigerated storage and its shelf-life extension by chitosan.

    PubMed

    Cao, Rong; Xue, Chang-Hu; Liu, Qi

    2009-05-31

    Changes in microbial flora of Pacific oysters (Crassostrea gigas) during storage at 5+/-1 degrees C were analyzed and the antimicrobial activity of chitosan was studied to identify its potential in shelf-life extension. The dominant microorganisms were found to be Pseudomonas (22%) and Vibrionaceae (20%) in raw oysters. During storage, proportion of Pseudomonas increased significantly and reached 73% at the end of storage, while Vibrionaceae preserved a level of approximate 20%. Wide-spectrum antibacterial property of chitosan against the bacteria isolated from oysters was discovered, and chitosan concentration of 5.0 g/L was eventually determined for application in oyster preservation. Based on microbiological analysis, biochemical indices determination and sensory evaluation, shelf-life of oysters stored at 5+/-1 degrees C was determined. Data showed that chitosan treatment extended the shelf-life of oysters from 8-9 days to 14-15 days.

  3. High cone-angle x-ray computed micro-tomography with 186 GigaVoxel datasets

    NASA Astrophysics Data System (ADS)

    Myers, Glenn R.; Latham, Shane J.; Kingston, Andrew M.; Kolomazník, Jan; Krajíček, Václav; Krupka, TomáÅ.¡; Varslot, Trond K.; Sheppard, Adrian P.

    2016-10-01

    X-ray computed micro-tomography systems are able to collect data with sub-micron resolution. This high- resolution imaging has many applications but is particularly important in the study of porous materials, where the sub-micron structure can dictate large-scale physical properties (e.g. carbonates, shales, or human bone). Sample preparation and mounting become diffiult for these materials below 2mm diameter: consequently, a typical ultra-micro-CT reconstruction volume (with sub-micron resolution) will be around 3k x 3k x 10k voxels, with some reconstructions becoming much larger. In this paper, we discuss the hardware (MPI-parallel CPU/GPU) and software (python/C++/CUDA) tools used at the ANU CTlab to reconstruct 186 GigaVoxel datasets.

  4. Whole transcriptome profiling of successful immune response to Vibrio infections in the oyster Crassostrea gigas by digital gene expression analysis.

    PubMed

    de Lorgeril, Julien; Zenagui, Reda; Rosa, Rafael D; Piquemal, David; Bachère, Evelyne

    2011-01-01

    The cultivated Pacific oyster Crassostrea gigas has suffered for decades large scale summer mortality phenomenon resulting from the interaction between the environment parameters, the oyster physiological and/or genetic status and the presence of pathogenic microorganisms including Vibrio species. To obtain a general picture of the molecular mechanisms implicated in C. gigas immune responsiveness to circumvent Vibrio infections, we have developed the first deep sequencing study of the transcriptome of hemocytes, the immunocompetent cells. Using Digital Gene Expression (DGE), we generated a transcript catalog of up-regulated genes from oysters surviving infection with virulent Vibrio strains (Vibrio splendidus LGP32 and V. aestuarianus LPi 02/41) compared to an avirulent one, V. tasmaniensis LMG 20012(T). For that an original experimental infection protocol was developed in which only animals that were able to survive infections were considered for the DGE approach. We report the identification of cellular and immune functions that characterize the oyster capability to survive pathogenic Vibrio infections. Functional annotations highlight genes related to signal transduction of immune response, cell adhesion and communication as well as cellular processes and defence mechanisms of phagocytosis, actin cytosqueleton reorganization, cell trafficking and autophagy, but also antioxidant and anti-apoptotic reactions. In addition, quantitative PCR analysis reveals the first identification of pathogen-specific signatures in oyster gene regulation, which opens the way for in depth molecular studies of oyster-pathogen interaction and pathogenesis. This work is a prerequisite for the identification of those physiological traits controlling oyster capacity to survive a Vibrio infection and, subsequently, for a better understanding of the phenomenon of summer mortality.

  5. Upregulating Nrf2-dependent antioxidant defenses in Pacific oysters Crassostrea gigas: Investigating the Nrf2/Keap1 pathway in bivalves.

    PubMed

    Danielli, Naissa Maria; Trevisan, Rafael; Mello, Danielle Ferraz; Fischer, Kelvis; Deconto, Vanessa Schadeck; da Silva Acosta, Daiane; Bianchini, Adalto; Bainy, Afonso Celso Dias; Dafre, Alcir Luiz

    2017-05-01

    Analysis of the Pacific oyster Crassostrea gigas annotated genome revealed genes with conserved sequences belonging to typical cap 'n' collar Nrf2 domain, a major player in antioxidant protection, and domains belonging to Nrf2 cytoplasmic repressor (Keap1), but little is known about Nrf2/Keap1 induction in bivalves. C. gigas were exposed to waterborne 10 and 30μM curcumin, a known inducer of the mammalian Nrf2. Curcumin disappeared from the seawater after 10h, and accumulated in the gills (10h) and digestive gland (10-96h). A clear induction of glutathione (GSH)-related antioxidant defenses was observed at 96h in the gills of curcumin exposed animals (10 and 30μM), including GSH levels, and the activity of glutathione reductase (GR), glutathione peroxidase (GPx), and glutathione S-transferase (GST). This response was completely absent in the digestive gland, in line with the idea that bivalve gills act as a major site for antioxidant protection under acute exposure. The relative mRNA levels coding glutamate-cysteine ligase, GR, GPx2 and GSTpi were clearly induced by curcumin treatment (30μM, 24h). Curcumin pre-treatment for 96h increased oyster resistance to cumene hydroperoxide, but neither Nrf2 nor Keap1 genes were modulated by curcumin. However, the conserved sequences belonging to typical Nrf2 and Keap1 domains, and the notorious induction of antioxidant defense-related genes known to be controlled by Nrf2 in mammals, indicates a functional Nrf2/Keap1 pathway in bivalves, and curcumin seems to be a new tool to investigate the antioxidant response in bivalves.

  6. Effects of low-dose exposure to pesticide mixture on physiological responses of the Pacific oyster, Crassostrea gigas.

    PubMed

    Geret, F; Burgeot, T; Haure, J; Gagnaire, B; Renault, T; Communal, P Y; Samain, J F

    2013-12-01

    This study investigated the effects on the physiology of Pacific oyster, Crassostrea gigas, of a mixture of pesticides containing 0.8 μg L(-1) alachlor, 0.6 μg L(-1) metolachlor, 0.7 μg L(-1) atrazine, 0.6 μg L(-1) terbuthylazine, 0.5 μg L(-1) diuron, 0.6 μg L(-1) fosetyl aluminum, 0.05 μg L(-1) carbaryl, and 0.7 μg L(-1) glyphosate for a total concentration of 4.55 μg L(-1) . The total nominal concentration of pesticides mixture corresponds to the pesticide concentrations in the shellfish culture area of the Marennes-Oleron basin. Two varieties of C. gigas were selected on the foreshore, based on their characteristics in terms of resistance to summer mortality, to assess the effects of the pesticide mixture after 7 days of exposure under controlled conditions. The early effects of the mixture were assessed using enzyme biomarkers of nitrogen metabolism (GS, glutamine synthetase), detoxification metabolism (GST, glutathione S-transferase), and oxidative stress (CAT, catalase). Sublethal effects on hemocyte parameters (phagocytosis and esterase activity) and DNA damages (DNA adducts) were also measured. Changes in metabolic activities were characterized by increases in GS, GST, and CAT levels on the first day of exposure for the "resistant" oysters and after 3-7 days of exposure for the "susceptible" oysters. The formation of DNA adducts was detected after 7 days of exposure. The percentage of hemocyte esterase-positive cells was reduced in the resistant oysters, as was the hemocyte phagocytic capacity in both oyster varieties after 7 days of exposure to the pesticide mixture. This study highlights the need to consider the low doses and the mixture of pesticides to evaluate the effects of these molecules on organisms.

  7. Utilising caging techniques to investigate metal assimilation in Nucella lapillus, Mytilus edulis and Crassostrea gigas at three Irish coastal locations

    NASA Astrophysics Data System (ADS)

    Giltrap, Michelle; Macken, Ailbhe; Davoren, Maria; McGovern, Evin; Foley, Barry; Larsen, Martin; White, Jonathan; McHugh, Brendan

    2013-11-01

    Pollution by metals has been of increasing concern for a number of decades but at present, the mechanism of metal accumulation in sentinel species is not fully understood and further studies are required for environmental risk assessment of metals in aquatic environments. The use of caging techniques has proven to be useful for assessment of water quality in coastal and estuarine environments. This study investigates the application of caging techniques for monitoring uptake of 20 elements [Li, Na, Mg, Al, P, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, As, Sb, Pb, Hg, Cd and Zn] in three marine species namely Nucella lapillus, Mytilus edulis and Crassostrea gigas. Stable isotopes were used to determine predatory effects and also used for modelling metal uptake in test species and to track nutrient assimilation. Metal levels were monitored at three different coastal locations, namely Dublin Bay, Dunmore East and Omey Island over 18 weeks. Significant differences in concentrations of Mn, Co and Zn between mussels and oysters were found. Correlations between cadmium levels in N. lapillus and δ13C and δ15N suggest dietary influences in Cd uptake. Levels of Zn were highest in C. gigas compared to the other two species and levels of Zn were most elevated at the Dunmore East site. Copper levels were more elevated in all test species at both Dublin Bay and Dunmore East. Mercury was raised in all species at Dunmore East compared to the other two sites. Biotic accumulation of metals in the test species demonstrates that caging techniques can provide a valid tool for biomonitoring in metal impacted areas.

  8. Whole Transcriptome Profiling of Successful Immune Response to Vibrio Infections in the Oyster Crassostrea gigas by Digital Gene Expression Analysis

    PubMed Central

    de Lorgeril, Julien; Zenagui, Reda; Rosa, Rafael D.; Piquemal, David; Bachère, Evelyne

    2011-01-01

    The cultivated Pacific oyster Crassostrea gigas has suffered for decades large scale summer mortality phenomenon resulting from the interaction between the environment parameters, the oyster physiological and/or genetic status and the presence of pathogenic microorganisms including Vibrio species. To obtain a general picture of the molecular mechanisms implicated in C. gigas immune responsiveness to circumvent Vibrio infections, we have developed the first deep sequencing study of the transcriptome of hemocytes, the immunocompetent cells. Using Digital Gene Expression (DGE), we generated a transcript catalog of up-regulated genes from oysters surviving infection with virulent Vibrio strains (Vibrio splendidus LGP32 and V. aestuarianus LPi 02/41) compared to an avirulent one, V. tasmaniensis LMG 20012T. For that an original experimental infection protocol was developed in which only animals that were able to survive infections were considered for the DGE approach. We report the identification of cellular and immune functions that characterize the oyster capability to survive pathogenic Vibrio infections. Functional annotations highlight genes related to signal transduction of immune response, cell adhesion and communication as well as cellular processes and defence mechanisms of phagocytosis, actin cytosqueleton reorganization, cell trafficking and autophagy, but also antioxidant and anti-apoptotic reactions. In addition, quantitative PCR analysis reveals the first identification of pathogen-specific signatures in oyster gene regulation, which opens the way for in depth molecular studies of oyster-pathogen interaction and pathogenesis. This work is a prerequisite for the identification of those physiological traits controlling oyster capacity to survive a Vibrio infection and, subsequently, for a better understanding of the phenomenon of summer mortality. PMID:21829707

  9. Effects of Antifouling Biocides on Molecular and Biochemical Defense System in the Gill of the Pacific Oyster Crassostrea gigas

    PubMed Central

    Park, Mi Seon; Kim, Young Dae; Kim, Bo-Mi; Kim, Youn-Jung; Kim, Jang Kyun; Rhee, Jae-Sung

    2016-01-01

    Antifouling biocides such as organotin compounds and their alternatives are potent toxicants in marine ecosystems. In this study, we employed several molecular and biochemical response systems of the Pacific oyster Crassostrea gigas to understand a potential mode of action of antifouling biocides (i.e. tributyltin (TBT), diuron and irgarol) after exposure to different concentrations (0.01, 0.1, and 1 μg L-1) for 96 h. As a result, all the three antifouling biocides strongly induced the antioxidant defense system. TBT reduced both enzymatic activity and mRNA expression of Na+/K+-ATPase and acetylcholinesterase (AChE). Lower levels of both Na+/K+-ATPase activity and AChE mRNA expression were observed in the diuron-exposed oysters compared to the control, while the irgarol treatment reduced only the transcriptional expression of AChE gene. We also analyzed transcript profile of heat shock protein (Hsp) superfamily in same experimental conditions. All antifouling biocides tested in this study significantly modulated mRNA expression of Hsp superfamily with strong induction of Hsp70 family. Taken together, overall results indicate that representative organotin TBT and alternatives have potential hazardous effects on the gill of C. gigas within relatively short time period. Our results also suggest that analyzing a series of molecular and biochemical parameters can be a way of understanding and uncovering the mode of action of emerging antifouling biocides. In particular, it was revealed that Pacific oysters have different sensitivities depend on the antifouling biocides. PMID:28006823

  10. Jumbo squid (Dosidicus gigas) mantle collagen: extraction, characterization, and potential application in the preparation of chitosan-collagen biofilms.

    PubMed

    Uriarte-Montoya, Mario Hiram; Arias-Moscoso, Joe Luis; Plascencia-Jatomea, Maribel; Santacruz-Ortega, Hisila; Rouzaud-Sández, Ofelia; Cardenas-Lopez, Jose Luis; Marquez-Rios, Enrique; Ezquerra-Brauer, Josafat Marina

    2010-06-01

    Collagen-based biomaterials have been widely used due to its binding capabilities. However the properties and potential use of new collagen sources are still under investigation. Fish by-products are an excellent source of collagen. Thus, acid-soluble collagen (ASC) was extracted, and biochemical and physicochemically characterized from one under-utilized specie, jumbo squid (Dosidicus gigas). In addition, commercial chitosan (95-50%)-ASC (5-50%) blend films were successfully prepared by casting, and characterized by infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The molecular masses of the ASC subunits were about 190kDa, 110kDa, and 97kDa, the content of proline and hydroxyproline was 10.9% and 2.8%, respectively. The FT-IR and nuclear magnetic resonance spectra ((1)H NMR) confirmed collagen peptidic crosslinks, and one endothermic peak was found at 119 degrees C. The FT-IR spectrum showed that chitosan and ASC remain linked into the films mainly due to hydrogen bonding. The 85:15 (chitosan:ASC) ratio was selected for its thermal and mechanical analyses. The thermograms of this film indicated the presence of two peaks, one at 87-98 degrees C and the other at 142-182 degrees C. The chitosan:ASC blend produced a transparent and brittle film, with high percentage of elongation at break, and low tensile strength in comparison to chitosan films. D. gigas mantle might be useful as a new source of plasticizer agent in the preparation of biofilms in composites with chitosan.

  11. Comparative responses of sperm cells and embryos of Pacific oyster (Crassostrea gigas) to exposure to metolachlor and its degradation products.

    PubMed

    Mai, Huong; Gonzalez, Patrice; Pardon, Patrick; Tapie, Nathalie; Budzinski, Hélène; Cachot, Jérôme; Morin, Bénédicte

    2014-02-01

    Metolachlor is one of the most intensively used chloroacetanilide herbicides in agriculture. Consequently, it has been frequently detected in coastal waters as well as its major degradation products, metolachlor ethane sulfonic acid (MESA) and metolachlor oxanilic acid (MOA) which are encountered at higher concentrations than metolachlor. Although a few studies of metolachlor toxicity have been conducted on marine organisms, little is known about the environmental toxicity of metolachlor degradation products. In this study, the deleterious effects of metolachlor and its degradation products on spermatozoa and embryos of Crassostrea gigas have been compared using biomarkers of developmental defects, DNA damage and gene transcription levels. After 24h exposure, significant increases in the percentage of abnormal D-larvae and DNA damage were observed from 0.01 μg L(-1) for S-metolachlor and 0.1 μg L(-1) for MESA and MOA. Results showed that S-metolachlor was more embryotoxic and genotoxic than its degradation products. Oyster sperm was also very sensitive to metolachlor exposure and followed the pattern: metolachlor (0.01 μg L(-1))>MOA (0.1 μg L(-1))>MESA (1 μg L(-1)). Metolachlor and MESA mainly triggered variations in the transcription level of genes encoding proteins involved in oxidative stress responses (mitochondrial superoxide dismutase and catalase). Overall, no significant variation in transcription levels could be detected in C. gigas embryos exposed to MOA. This study demonstrates that metolachlor and its main degradation products have the potential to impact several steps of oyster development and therefore recruitment in coastal areas exposed to chronic inputs of pesticides.

  12. The second bactericidal permeability increasing protein (BPI) and its revelation of the gene duplication in the Pacific oyster, Crassostrea gigas.

    PubMed

    Zhang, Yang; He, Xiaocui; Li, Xiaomei; Fu, Dingkun; Chen, Jinhui; Yu, Ziniu

    2011-03-01

    A novel homolog of BPI was cloned from the hemocyte cDNA of Crassostrea gigas and designed as Cg-BPI2, which share the highest sequence identity with the well-known Cg-BPI (designed as Cg-BPI1). The complete cDNA of Cg-BPI2 included an open reading frame (ORF) of 1440 bp, and 3' and 5' untranslated regions (UTR's) of 49 bp and 166 bp, respectively. The ORF encoded a putative protein of 479 amino acids with predicted 22-aa hydrophobic signal peptide. The phylogenetic analysis showed that one of the gene duplications could have resulted in the emergence of two homologs of BPI in oysters, which probably might have occurred after the gastropod-bivalve divergence. Furthermore, molecular modeling analysis showed that both Cg-BPIs are similar to a highly extended boomerang like shape of human BPI, consisting of an N- and C-terminal barrel and a central β-sheet. Comparison of the electrostatic surface potentials revealed that surfaces of Cg-BPI2 have more intense positive charge than that of human BPI and the Cg-BPI1. The recombinant N-terminal barrel domain showed a high affinity to LPS and can effectively kill Gram-negative bacteria. The mRNAs of two Cg-BPIs were observed in all tissues examined with the highest expression in gills. The mRNAs expression profiles in response to bacterial challenge revealed that they were inducible under infection, but with a distinct and complementary expression patterns between Cg-BPI1 and Cg-BPI2. Our findings of this second BPI gene demonstrated presence of its gene duplication for the first time in invertebrate and it appears to be one of effective LPS-binding AMPs in elimination of Gram-negative pathogens C. gigas.

  13. Effect of 4-nonylphenol on the immune response of the Pacific oyster Crassostrea gigas following bacterial infection with Vibrio campbellii.

    PubMed

    Hart, Courtney E; Lauth, Michael J; Hunter, Cassidy S; Krasny, Brennan R; Hardy, Kristin M

    2016-11-01

    The xenoestrogen 4-nonylphenol (NP) is a ubiquitous aquatic pollutant and has been shown to impair reproduction, development, growth and, more recently, immune function in marine invertebrates. We investigated the effects of short-term (7 d) exposure to low (2 μg l(-1)) and high (100 μg l(-1)) levels of NP on cellular and humoral elements of the innate immune response of Crassostrea gigas to a bacterial challenge. To this end, we measured 1) total hemocyte counts (THC), 2) relative transcript abundance of ten immune-related genes (defh1, defh2, bigdef1, bigdef2, bpi, lysozyme-1, galectin, C-type lectin 2, timp, and transglutaminase) in the hemocytes, gill and mantle, and 3) hemolymph plasma lysozyme activity, following experimental Vibrio campbellii infection. Both low and high levels of NP were found to repress a bacteria-induced increase in THC observed in the control oysters. While several genes were differentially expressed following bacterial introduction (bigdef2, bpi, lysozyme-1, timp, transglutaminase), only two genes (bpi in the hemocytes, transglutaminase in the mantle) exhibited a different bacteria-induced expression profile following NP exposure, relative to the control oysters. Independently of infection-status, exposure to NP also altered mRNA transcript abundance of several genes (bpi, galectin, C-type lectin 2) in naïve, saline-injected oysters. Finally, plasma lysozyme activity levels were significantly higher in low dose NP-treated oysters (both naïve and bacteria challenged) relative to control oysters. Combined, these results suggest that exposure to ecologically-relevant (low) and extreme (high) levels of NP can alter both cellular and humoral elements of the innate immune response in C. gigas, an aquaculture species of global economic importance.

  14. Characterization of chitinase-like proteins (Cg-Clp1 and Cg-Clp2) involved in immune defence of the mollusc Crassostrea gigas.

    PubMed

    Badariotti, Fabien; Lelong, Christophe; Dubos, Marie-Pierre; Favrel, Pascal

    2007-07-01

    Chitinase-like proteins have been identified in insects and mammals as nonenzymatic members of the glycoside hydrolase family 18. Recently, the first molluscan chitinase-like protein, named Crassostrea gigas (Cg)-Clp1, was shown to control the proliferation and synthesis of extracellular matrix components of mammalian chondrocytes. However, the precise physiological roles of Cg-Clp1 in oysters remain unknown. Here, we report the cloning and the characterization of a new chitinase-like protein (Cg-Clp2) from the oyster Crassostrea gigas. Gene expression profiles monitored by quantitative RT-PCR in adult tissues and through development support its involvement in tissue growth and remodelling. Both Cg-Clp1- and Cg-Clp2-encoding genes were transcriptionally stimulated in haemocytes in response to bacterial lipopolysaccharide challenge, strongly suggesting that these two close paralogous genes play a role in oyster immunity.

  15. Organochlorine compounds in blue mussels, Mytilus edulis, and Pacific oysters, Crassostrea gigas, from seven sites in the Lower Saxonian Wadden Sea, Southern North Sea.

    PubMed

    Dörr, Barbara; Liebezeit, Gerd

    2009-12-01

    Blue mussels (Mytilus edulis) and Pacific oysters (Crassostrea gigas) collected at seven locations in the Lower Saxonian Wadden Sea in January and February 2007 were analysed for organochlorine compounds. Contaminants were present in all samples, albeit with variable amounts and composition. The highest values were found in the Jade Bay. Congener PCB 153 was the contaminant which had the highest content of all organochlorines tested (475.75-937.39 ng/g lipid). DDT was detected in one sample only while DDD and DDE were found in all samples, the latter with contents up to 351.34 ng/g lipid. No clear differentiation could be made in terms of accumulation of organochlorines for M. edulis and C. gigas. Comparison with data from 2001 to 2006 showed an increase in 2007, which may be due to the different season the samples were taken.

  16. Effects of In Vitro Exposure to Diarrheic Toxin Producer Prorocentrum lima on Gene Expressions Related to Cell Cycle Regulation and Immune Response in Crassostrea gigas

    PubMed Central

    de Jesús Romero-Geraldo, Reyna; García-Lagunas, Norma; Hernández-Saavedra, Norma Yolanda

    2014-01-01

    Background Crassostrea gigas accumulates diarrheic shellfish toxins (DSP) associated to Prorocentrum lima of which Okadaic acid (OA) causes specific inhibitions of serine and threonine phosphatases 1 and 2A. Its toxic effects have been extensively reported in bivalve mollusks at cellular and physiological levels, but genomic approaches have been scarcely studied. Methodology/Principal Findings Acute and sub-chronic exposure effects of P. lima were investigated on farmed juvenile C. gigas (3–5 mm). The Pacific oysters were fed with three dinoflagellate concentrations: 0.3, 3, and 30×103 cells mL−1 along with a nontoxic control diet of Isochrysis galbana. The effects of P. lima on C. gigas were followed by analyzing expression levels of a total of four genes, three involved in cell cycle regulation and one in immune response by polymerase chain reaction and real time quantitative PCR, where changes in time and cell concentration were found. The highest expression levels were found in oysters fed 3×103 cells mL−1 at 168 h for the cycle regulator p21 protein (9 fold), chromatin assembly factor 1 p55 subunit (8 fold), elongation factor 2 (2 fold), and lipopolysaccharide/β-1, 3 glucan binding protein (13 fold above base line). Additionally, the transcript level of all the genes decreased in oysters fed wich the mixed diet 30×103 cells mL−1 of dinoflagellate after 72 h and was lowest in the chromatin assembly factor 1 p55 subunit (0.9 fold below baseline). Conclusions On C. gigas the whole cell ingestion of P lima caused a clear mRNA modulation expression of the genes involved in cell cycle regulation and immune system. Over-expression could be related to DNA damage, disturbances in cell cycle continuity, probably a genotoxic effect, as well as an activation of its innate immune system as first line of defense. PMID:24825133

  17. A comparison of fishery biology of jumbo flying squid, Dosidicus gigas outside three Exclusive Economic Zones in the Eastern Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Liu, Bilin; Chen, Xinjun; Yi, Qian

    2013-05-01

    Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones (EEZs) of various countries due to its commercial and ecological importance, limited biological information is available from waters outside these EEZs. In this paper, we examined D. gigas fishery biology from waters outside Chilean, Peruvian and Costa Rican EEZs, based on the fishery data collected by Chinese jigging vessels during 2006 to 2010. The dominant mantle lengths of D. gigas were 350-450 mm, 250-400 mm and 250-350 mm outside Chilean, Peruvian and Costa Rican EEZs, respectively. Size structure analysis show that a medium-sized group existed mostly in the waters outside the Chilean and Peruvian EEZs, whereas a small-sized group occurred mainly in the waters outside the Costa Rican EEZ. The longevity of the squid outside the Costa Rican EEZ was less than 10 months, while most of those outside Chilean and Peruvian EEZs were about 1-1.5 years and very few large individuals were 1.5-2 years old. A higher percentage of mature individuals existed outside Costa Rican EEZ implying the region as a potential spawning ground, while lower proportions of mature squid outside the Peruvian and Chilean EEZs indicated that spawning may be occurring outside our study area. Spatial differences in sizes at maturity of the squid are thought to be result from different environmental factors especially different temperature and nutrition among the three areas. Stomach-content analysis showed that cannibalism was important in the diet of D. gigas. Stress generated by jigging may increase the incidence of cannibalism.

  18. Expression patterns indicate that BMP2/4 and Chordin, not BMP5-8 and Gremlin, mediate dorsal-ventral patterning in the mollusk Crassostrea gigas.

    PubMed

    Tan, Sujian; Huan, Pin; Liu, Baozhong

    2016-12-16

    Though several bilaterian animals use a conserved BMP2/4-Chordin antagonism to pattern the dorsal-ventral (DV) axis, the only lophotrochozoan species in which early DV patterning has been studied to date, the leech Helobdella robusta, appears to employ BMP5-8 and Gremlin. These findings call into question the conservation of a common DV patterning mechanism among bilaterian animals. To explore whether the unusual DV patterning mechanism in H. robusta is also used in other lophotrochozoan species, we investigated the expression of orthologous genes in the early embryo of a bivalve mollusk, Crassostrea gigas. Searching of the genome and phylogenetic analysis revealed that C. gigas possesses single orthologs of BMP2/4, Chordin, and BMP5-8 and no Gremlin homolog. Whole mount in situ hybridization revealed mRNA localization of BMP2/4 and Chordin on the opposite sides of embryos, suggesting the potential involvement of a BMP2/4-Chordin antagonism in DV patterning in this species. Furthermore, universal BMP5-8 expression and the absence of a Gremlin homolog in the C. gigas genome called into question any major contribution by BMP5-8 and Gremlin to early DV patterning in this species. Additionally, we identified seven genes showing asymmetric expression along the DV axis, providing further insight into DV patterning in C. gigas. We present the first report of a Chordin gene in a lophotrochozoan species and of the opposite expression of BMP2/4 (dorsal) and Chordin (ventral) along the D/V axis of a lophotrochozoan embryo. The findings of this study further the knowledge of axis formation in lophotrochozoan species and provide insight into the evolution of the animal DV patterning mechanism.

  19. Development of genomic microsatellite multiplex PCR using dye-labeled universal primer and its validation in pedigree analysis of Pacific oyster ( Crassostrea gigas)

    NASA Astrophysics Data System (ADS)

    Liu, Ting; Li, Qi; Song, Junlin; Yu, Hong

    2017-02-01

    There is an increasing requirement for traceability of aquaculture products, both for consumer protection and for food safety. There are high error rates in the conventional traceability systems depending on physical labels. Genetic traceability technique depending on DNA-based tracking system can overcome this problem. Genealogy information is essential for genetic traceability, and microsatellite DNA marker is a good choice for pedigree analysis. As increasing genotyping throughput of microsatellites, microsatellite multiplex PCR has become a fast and cost-effective technique. As a commercially important cultured aquatic species, Pacific oyster Crassostrea gigas has the highest global production. The objective of this study was to develop microsatellite multiplex PCR panels with dye-labeled universal primer for pedigree analysis in C. gigas, and these multiplex PCRs were validated using 12 full-sib families with known pedigrees. Here we developed six informative multiplex PCRs using 18 genomic microsatellites in C. gigas. Each multiplex panel contained a single universal primer M13(-21) used as a tail on each locus-specific forward primer and a single universal primer M13(-21) labeled with fluorophores. The polymorphisms of the markers were moderate, with an average of 10.3 alleles per locus and average polymorphic information content of 0.740. The observed heterozygosity per locus ranged from 0.492 to 0.822. Cervus simulations revealed that the six panels would still be of great value when massive families were analysed. Pedigree analysis of real offspring demonstrated that 100% of the offspring were unambiguously allocated to their parents when two multiplex PCRs were used. The six sets of multiplex PCRs can be an important tool for tracing cultured individuals, population genetic analysis, and selective breeding program in C. gigas.

  20. Arsenic and arsenic species in cultured oyster (Crassostrea gigas and C. corteziensis) from coastal lagoons of the SE Gulf of California, Mexico.

    PubMed

    Bergés-Tiznado, Magdalena E; Páez-Osuna, Federico; Notti, Alessandra; Regoli, Francesco

    2013-01-01

    The aim of this study was to evaluate the bioavailability of arsenic (As) through cultured oyster Crassostrea gigas and Crassostrea corteziensis from four coastal lagoons (SE Gulf of California). Organisms were collected in two seasons (rainy and dry season), and they were analyzed for total arsenic and chemical speciation of this element. The concentrations of As in oyster soft tissue fluctuated between 5.44 and 9.56 μg/g for rainy season and 6.46 and 8.33 μg/g for dry season (dry weight) in C. gigas. In C. corteziensis, the As concentrations were <5 μg/g for both seasons (dry weight). Arsenic speciation indicated arsenobetaine as the major arseno-compound accounting for 43.2-76.3 % of total content of As. Lower contributions were obtained for non-extractable As (11.3-17.5 %) and other molecules such as arsenocholine and methyl-arsonate (<5 %). Inorganic arsenic was detectable in only two samples, at concentrations lower than <0.1 μg/g. These As data are the first generated for these mollusks in NW Mexico and indicate that C. gigas and C. corteziensis farmed in this area are safe for human consumption in terms of arseno-compounds.

  1. Causes and effects of a highly successful marine invasion: Case-study of the introduced Pacific oyster Crassostrea gigas in continental NW European estuaries

    NASA Astrophysics Data System (ADS)

    Troost, Karin

    2010-10-01

    Since the 1960's, the Pacific oyster Crassostrea gigas has been introduced for mariculture at several locations within NW Europe. The oyster established itself everywhere and expanded rapidly throughout the receiving ecosystems, forming extensive and dense reef structures. It became clear that the Pacific oyster induced major changes in NW European estuaries. This paper reviews the causes of the Pacific oyster's remarkably successful establishment and spread in The Netherlands and neighbouring countries, and includes a comprehensive review of consequences for the receiving communities. Ecosystem engineering by C. gigas and a relative lack of natural enemies in receiving ecosystems are identified as the most important characteristics facilitating the invader's successful establishment and expansion. The Pacific oyster's large filtration capacity and eco-engineering characteristics induced many changes in receiving ecosystems. Different estuaries are affected differently; in the Dutch Oosterschelde estuary expanding stocks saturate the carrying capacity whereas in the Wadden Sea no such problems exist. In general, the Pacific oyster seems to fit well within continental NW European estuarine ecosystems and there is no evidence that the invader outcompetes native bivalves. C. gigas induces changes in plankton composition, habitat heterogeneity and biodiversity, carrying capacity, food webs and parasite life cycles. The case of the Pacific oyster in NW European estuaries is only one example in an increasing series of biological invasions mediated by human activities. This case-study will contribute to further elucidating general mechanisms in marine invasions; invasions that sometimes appear a threat, but can also contribute to ecological complexity.

  2. Horizontal movements, vertical-habitat utilization and diet of the jumbo squid ( Dosidicus gigas) in the Pacific Ocean off Baja California Sur, Mexico

    NASA Astrophysics Data System (ADS)

    Bazzino, Gastón; Gilly, William F.; Markaida, Unai; Salinas-Zavala, César A.; Ramos-Castillejos, Jorge

    2010-07-01

    We deployed four pop-up archival-transmitting (PAT) tags on jumbo squid ( Dosidicus gigas) collected in the Pacific Ocean off the main entrance to Magdalena Bay on the Baja California peninsula in June 2005. This is the first successful deployment of PAT tags on jumbo squid in an area outside the Gulf of California. Summary data were obtained through the ARGOS satellite system for three of the tags; the fourth tag was physically recovered. All of the tagged squid tended to remain on the shallow continental shelf for several days after tagging and then moved offshore into deeper water. Three of the four squid appeared to migrate in a general southerly direction while the fourth remained offshore of Magdalena Bay. All of the squid spent most daylight hours at depths that were associated with the hypoxic oxygen minimum layer, and at night they spent a majority of time in the upper 50 m of the water column. Stomach content analysis and tag temperature-depth data during the first days after tagging revealed that the squid were feeding on pelagic red crabs ( Pleuroncodes planipes) and several larger, neritic fishes over the continental shelf off Magdalena Bay during a seasonal nearshore upwelling. Comparison of our results with those previously collected in the Gulf of California reveal that Dosidicus gigas can vary its behavior and diet to suit local environmental conditions. This adaptability is likely to be an important factor in the ability of D. gigas to invade and colonize new areas.

  3. Effects of heavy metals on the expression of a zinc-inducible metallothionein-III gene and antioxidant enzyme activities in Crassostrea gigas.

    PubMed

    Cong, Ming; Wu, Huifeng; Liu, Xiaoli; Zhao, Jianmin; Wang, Xuan; Lv, Jiasen; Hou, Lin

    2012-10-01

    Sequestration by metallothioneins and antioxidant defense are two kinds of important defense mechanisms employed by mollusks to minimize adverse effects caused by heavy metal contaminants in marine environment. In the present study, a novel metallothionein gene, CgMT-III, was cloned from Crassostrea gigas, consisting of eighteen conserved cysteine residues and encoding a MT III-like protein with two tandem β domains. The expression level of CgMT-III transcript induced by zinc was much higher than that induced by cadmium exposure. It suggested that CgMT-III was perhaps mainly involved in homeostatic control of zinc metabolism, which was distinct from previously identified MTs in C. gigas. Among the tested antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), SOD and GPx showed varying up-regulations in a tissue-specific manner, while CAT activities were inhibited in both gill and hepatopancreas from C. gigas exposed to heavy metals. It can be inferred that CgMT-III was mainly involved in zinc homeostasis, and CgMT-III gene together with CAT enzyme could be potential biomarkers to indicate heavy metal, especially zinc pollution in marine organisms.

  4. Benefits of oxygen incorporation in atomic laminates

    NASA Astrophysics Data System (ADS)

    Dahlqvist, Martin

    2016-04-01

    Atomic laminates such as MAX phases benefit from the addition of oxygen in many ways, from the formation of a protective oxide surface layer with self-healing capabilities when cracks form to the tuning of anisotropic conductivity. In this paper oxygen incorporation and vacancy formation in M 2AlC (M  =  Ti, V, Cr) MAX phases have been studied using first-principles calculations where the focus is on phase stability and electronic structure for different oxygen and/or vacancy configurations. Oxygen prefers different lattice sites depending on M-element and this can be correlated to the number of available non-bonding M d-electrons. In Ti2AlC, oxygen substitutes carbon while in Cr2AlC it is located interstitially within the Al-layer. I predict that oxygen incorporation in Ti2AlC stabilizes the material, which explains the experimentally observed 12.5 at% oxygen (x  =  0.5) in Ti2Al(C1-x O x ). In addition, it is also possible to use oxygen to stabilize the hypothetical Zr2AlC and Hf2AlC. Hence, oxygen incorporation may be beneficial in many ways. Not only can it make a material more stable, but it also can act as a reservoir for internal self-healing with shorter diffusion paths.

  5. Acetyl-l-carnitine restores synaptic transmission and enhances the inducibility of stable LTP after oxygen-glucose deprivation.

    PubMed

    Kocsis, Kitti; Frank, Rita; Szabó, József; Knapp, Levente; Kis, Zsolt; Farkas, Tamás; Vécsei, László; Toldi, József

    2016-09-22

    Hypoxic circumstances result in functional and structural impairments of the brain. Oxygen-glucose deprivation (OGD) on hippocampal slices is a technique widely used to investigate the consequences of ischemic stroke and the potential neuroprotective effects of different drugs. Acetyl-l-carnitine (ALC) is a naturally occurring substance in the body, and it can therefore be administered safely even in relatively high doses. In previous experiments, ALC pretreatment proved to be effective against global hypoperfusion. In the present study, we investigated whether ALC can be protective in an OGD model. We are not aware of any earlier study in which the long-term potentiation (LTP) function on hippocampal slices was measured after OGD. Therefore, we set out to determine whether an effective ALC concentration has an effect on synaptic plasticity after OGD in the hippocampal CA1 subfield of rats. A further aim was to investigate the mechanism underlying the protective effect of this compound. The experiments revealed that ALC is neuroprotective against OGD in a dose-dependent manner, which is manifested not only in the regeneration of the impaired synaptic transmission after the OGD, but also in the inducibility and stability of the LTP. In the case of the most effective concentration of ALC (500μM), use of a phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) revealed that the PI3K/Akt signaling pathway has a key role in the restoration of the synaptic transmission and plasticity reached by ALC treatment.

  6. Acetyl-L-carnitine and oxaloacetate in post-treatment against LTP impairment in a rat ischemia model. An in vitro electrophysiological study.

    PubMed

    Kocsis, K; Knapp, L; Mészáros, J; Kis, Z; Farkas, T; Vécsei, L; Toldi, J

    2015-06-01

    A high proportion of research relating to cerebral ischemia focuses on neuroprotection. The application of compounds normally present in the organism is popular, because they do not greatly influence the synaptic activity by receptor modulation, and can be administered without serious side effects. Oxaloacetate (OxAc) and acetyl-L-carnitine (ALC) are such favorable endogenous molecules. ALC can exert a protective effect by improving the energy state of the neurons under ischemic conditions. A promising neuroprotective strategy is glutamate scavenging, which can be achieved by the intravenous administration of OxAc. This study involved the possible protective effects of ALC and OxAc in different post-treatment protocols against long-term potentiation (LTP) impairment. Ischemia was induced in rats by 2-vessel occlusion, which led to a decreased LTP relative to the control group. High-dose (200 mg/kg) ALC or OxAc post-treatment resulted in a higher potentiation relative to the 2VO group, but it did not reach the control level, whereas low-dose ALC (100 mg/kg) in combination with OxAc completely restored the LTP function. Many previous studies have concluded that ALC can be protective only as pretreatment. The strategy described here reveals that ALC can also be neuroprotective when utilized as post-treatment against ischemia.

  7. Acetyl-l-carnitine prevents serotonin-induced behavioural sensitization and dishabituation in Hirudo medicinalis.

    PubMed

    Traina, Giovanna; Ristori, Chiara; Brunelli, Marcello; Scuri, Rossana

    2013-09-15

    Several studies suggest that acetyl-l-carnitine (ALC) might influence learning processes. Along this line of investigation, we have previously shown that ALC impaired sensitization and dishabituation induced by nociceptive stimulation of the dorsal skin of the leech Hirudo medicinalis, in the behavioural paradigm of the swim induction (SI). In previous works we showed that 5HT was involved in both sensitization and dishabituation of SI acting through the second messenger cAMP. In this work, we have reported that for given doses and temporal ranges ALC was able to block sensitization and to impair dishabituation mimicked by the injection of 5-HT or 8Br-cAMP, a membrane permeable analogue of cAMP. Our results show that a single treatment with 2mM ALC was the most effective concentration to block the onset of sensitization induced by 5-HT injection and its major effects occurred 11 days after ALC treatment. 2mM ALC also blocked sensitization induced by 8Br-cAMP injection, whereas, ALC did not completely abolish dishabituation induced by 5-HT or 8Br-cAMP injection at the tested concentrations and at every time point.

  8. Low blood lymphocyte count at 30 days post transplant predicts worse acute GVHD and survival but not relapse in a large retrospective cohort.

    PubMed

    Gul, Z; Van Meter, E; Abidi, M; Ditah, I; Abdul-Hussein, M; Deol, A; Ayash, L; Lum, L G; Waller, E K; Ratanatharathorn, V; Uberti, J; Al-Kadhimi, Z

    2015-03-01

    Multiple reports have shown that low absolute lymphocyte count at day 30 (ALC30) after allogeneic hematopoietic SCT (AHSCT) is associated with higher risk of disease relapse and worse OS. However, these reports included heterogeneous populations with different grafts and GVHD prophylaxis. Therefore, we retrospectively evaluated the association of ALC30 with transplant outcomes in a cohort of 381 consecutive patients who underwent AHSCT between 2005 and 2010 and received T-replete PBSC grafts and Tacrolimus/Mycophenolate combination as GVHD prophylaxis. Median follow-up was 57 months. Lower ALC30 (⩽400 × 10(6)/L) was associated with lower OS and increased nonrelapse mortality (NRM) for the whole cohort as well as for recipients of SD and UD grafts separately. Lower ALC30 was associated with more severe acute GVHD (aGVHD; III-IV) for the entire cohort as well as for the SD and UD groups. No association was found between lower ALC30 and relapse. Pretransplant factors associated with lower ALC30 were: unrelated donors; HLA mismatch; older donors; lower recipient age; and lower CD34+ cell dose. In this large retrospective study, ALC30⩽400 × 10(6)/L was associated with worse OS, increased NRM and severe aGVHD.

  9. Acetyl-L-carnitine ameliorates mitochondrial dysfunction following contusion spinal cord injury.

    PubMed

    Patel, Samir P; Sullivan, Patrick G; Lyttle, Travis S; Rabchevsky, Alexander G

    2010-07-01

    In the present study, we evaluated the therapeutic efficacy of acetyl-l-carnitine (ALC) administration on mitochondrial dysfunction following tenth thoracic level contusion spinal cord injury (SCI) in rats. Initial results from experiments in vitro with naïve mitochondria showed that, in the absence of pyruvate, ALC can be used as an alternative substrate for mitochondrial respiration. Additionally, when added in vitro to mitochondria isolated from 24 h injured cords, ALC restored respiration rates to normal levels. For administration studies in vivo, injured rats were given i.p. injections of saline (vehicle) or ALC (300 mg/kg) at 15, 30 or 60 min post-injury, followed by one booster after 6 h. Mitochondria were isolated 24 h post-injury and assessed for respiration rates, activities of NADH dehydrogenase, cytochrome c oxidase and pyruvate dehydrogenase. SCI significantly (p < 0.05) decreased respiration rates and activities of all enzyme complexes, but ALC treatment significantly (p < 0.05) maintained mitochondrial respiration and enzyme activities compared with vehicle treatment. Critically, ALC administration in vivo at 15 min and 6 h post-injury versus vehicle, followed once daily for 7 days, significantly (p < 0.05) spared gray matter. In summary, ALC treatment maintains mitochondrial bioenergetics following contusion SCI and, thus, holds great potential as a neuroprotective therapy for acute SCI.

  10. Characterizing absolute lymphocyte count profiles in dimethyl fumarate–treated patients with MS

    PubMed Central

    Chan, Andrew; Gold, Ralf; Phillips, J. Theodore; Selmaj, Krzysztof; Chang, Ih; Novas, Mark; Rana, Jitesh; Marantz, Jing L.

    2016-01-01

    Abstract Background: Delayed-release dimethyl fumarate (DMF), indicated for the treatment of patients with relapsing-remitting multiple sclerosis (MS), is a disease-modifying therapy with potential immunomodulatory and neuroprotective effects. In clinical trials, DMF was associated with reduced white blood cell and absolute lymphocyte counts. Current US prescribing information recommends obtaining a complete blood count, including absolute lymphocyte count (ALC), before initiating and during DMF treatment. Methods: We conducted an integrated analysis of phase 2b/3/long-term extension studies of DMF in MS (N = 2,470) to characterize ALC profiles. Results: Mean ALCs decreased by 30% during the first year and then plateaued, remaining above the lower limit of normal (LLN). Among patients treated ≥6 months (N = 2,099), 2.2% experienced ALCs <500 mm3 persisting ≥6 months. ALCs remained ≥LLN in 84% and 76% of patients during the first 6 and 12 months, respectively; of these, 0.1% and 0%, respectively, developed ALCs <500 mm3 persisting ≥6 months at any time. Evidence of ALC improvement following DMF discontinuation was observed. DMF efficacy was not substantially different in patients with and without lymphopenia. Conclusion: Lymphocyte monitoring provides effective means for early identification of patients at risk for developing severe, prolonged lymphopenia. PMID:27347439

  11. Chronic cigarette smoking in alcohol dependence: associations with cortical thickness and N-acetylaspartate levels in the extended brain reward system.

    PubMed

    Durazzo, Timothy C; Mon, Anderson; Gazdzinski, Stefan; Meyerhoff, Dieter J

    2013-03-01

    Chronic smoking in alcohol dependence is associated with abnormalities in brain morphology and metabolite levels in large lobar regions (e.g. frontal lobe). Here, we evaluated if these abnormalities are specifically apparent in several cortical and select subcortical components of the extended brain reward system (BRS), a network that is critically involved in the development and maintenance of all forms of addictive disorders. We studied 33 non-smoking and 43 smoking alcohol-dependent individuals (ALC) with 1 week of abstinence and 42 non-smoking Controls. At 1.5 Tesla, we obtained regional measures of cortical thickness and N-acetylaspartate (NAA; a surrogate marker of neuronal integrity) concentration in major components of the BRS as well as the corresponding measures throughout the cortex. Smoking ALC and non-smoking ALC demonstrated decreased thickness compared with Controls in the dorsolateral prefrontal cortex (DLPFC), insula, orbitofrontal cortex (OFC), the total BRS, total frontal cortex and global cortex. Smoking ALC had significantly decreased thickness compared to non-smoking ALC in the ACC, insula, the total BRS and total frontal cortex. Smoking ALC had also lower NAA concentrations than both non-smoking ALC and Controls in the DLPFC, insula, superior corona radiata and the total BRS. Alcohol consumption and common medical and psychiatric co-morbidities did not mediate differences between smoking and non-smoking ALC. This dual modality magnetic resonance (MR) study indicated that chronic smoking in ALC was associated with significant cortical thinning and NAA abnormalities in anterior brain regions that are implicated in the development and maintenance of addictive disorders.

  12. White matter fiber compromise contributes differentially to attention and emotion processing impairment in alcoholism, HIV-infection, and their comorbidity.

    PubMed

    Schulte, T; Müller-Oehring, E M; Sullivan, E V; Pfefferbaum, A

    2012-10-01

    Alcoholism (ALC) and HIV-1 infection (HIV) each affects emotional and attentional processes and integrity of brain white matter fibers likely contributing to functional compromise. The highly prevalent ALC+HIV comorbidity may exacerbate compromise. We used diffusion tensor imaging (DTI) and an emotional Stroop Match-to-Sample task in 19 ALC, 16 HIV, 15 ALC+HIV, and 15 control participants to investigate whether disruption of fiber system integrity accounts for compromised attentional and emotional processing. The task required matching a cue color to that of an emotional word with faces appearing between the color cue and the Stroop word in half of the trials. Nonmatched cue-word color pairs assessed selective attention, and face-word pairs assessed emotion. Relative to controls, DTI-based fiber tracking revealed lower inferior longitudinal fasciculus (ilf) integrity in HIV and ALC+HIV and lower uncinate fasciculus (uf) integrity in all three patient groups. Controls exhibited Stroop effects to positive face-word emotion, and greater interference was related to greater callosal, cingulum and ilf integrity. By contrast, HIV showed greater interference from negative Stroop words during color-nonmatch trials, correlating with greater uf compromise. For face trials, ALC and ALC+HIV showed greater Stroop-word interference, correlating with lower cingulate and callosal integrity. Thus, in HIV, conflict resolution was diminished when challenging conditions usurped resources needed to manage interference from negative emotion and to disengage attention from wrongly cued colors (nonmatch). In ALC and ALC+HIV, poorer callosal integrity was related to enhanced emotional interference suggesting curtailed interhemispheric exchange needed between preferentially right-hemispheric emotion and left-hemispheric Stroop-word functions.

  13. The final spawning ground of Tachypleus gigas (Müller, 1785) on the east Peninsular Malaysia is at risk: a call for action.

    PubMed

    Nelson, Bryan Raveen; Satyanarayana, Behara; Moh, Julia Hwei Zhong; Ikhwanuddin, Mhd; Chatterji, Anil; Shaharom, Faizah

    2016-01-01

    Tanjung Selongor and Pantai Balok (State Pahang) are the only two places known for spawning activity of the Malaysian horseshoe crab - Tachypleus gigas (Müller, 1785) on the east coast of Peninsular Malaysia. While the former beach has been disturbed by several anthropogenic activities that ultimately brought an end to the spawning activity of T. gigas, the status of the latter remains uncertain. In the present study, the spawning behavior of T. gigas at Pantai Balok (Sites I-III) was observed over a period of thirty six months, in three phases, between 2009 and 2013. Every year, the crab's nesting activity was found to be high during Southwest monsoon (May-September) followed by Northeast (November-March) and Inter monsoon (April and October) periods. In the meantime, the number of female T. gigas in 2009-2010 (Phase-1) was higher (38 crabs) than in 2010-2011 (Phase-2: 7 crabs) and 2012-2013 (Phase-3: 9 crabs) for which both increased overexploitation (for edible and fishmeal preparations) as well as anthropogenic disturbances in the vicinity (sand mining since 2009, land reclamation for wave breaker/parking lot constructions in 2011 and fishing jetty construction in 2013) are responsible. In this context, the physical infrastructure developments have altered the sediment close to nesting sites to be dominated by fine sand (2.5Xφ ) with moderately-well sorted (0.6-0.7σφ), very-coarse skewed (-2.4SKφ), and extremely leptokurtic (12.6Kφ) properties. Also, increased concentrations of Cadmium (from 4.2 to 13.6 mg kg(-1)) and Selenium (from 11.5 to 23.3 mg kg(-1)) in the sediment, and Sulphide (from 21 to 28 µg l(-1)) in the water were observed. In relation to the monsoonal changes affecting sheltered beach topography and sediment flux, the spawning crabs have shown a seasonal nest shifting behaviour in-between Sites I-III during 2009-2011. However, in 2012-2013, the crabs were mostly restricted to the areas (i.e., Sites I and II) with high oxygen (5.5-8.0 mg l

  14. The final spawning ground of Tachypleus gigas (Müller, 1785) on the east Peninsular Malaysia is at risk: a call for action

    PubMed Central

    Moh, Julia Hwei Zhong; Ikhwanuddin, Mhd; Chatterji, Anil; Shaharom, Faizah

    2016-01-01

    Tanjung Selongor and Pantai Balok (State Pahang) are the only two places known for spawning activity of the Malaysian horseshoe crab - Tachypleus gigas (Müller, 1785) on the east coast of Peninsular Malaysia. While the former beach has been disturbed by several anthropogenic activities that ultimately brought an end to the spawning activity of T. gigas, the status of the latter remains uncertain. In the present study, the spawning behavior of T. gigas at Pantai Balok (Sites I-III) was observed over a period of thirty six months, in three phases, between 2009 and 2013. Every year, the crab’s nesting activity was found to be high during Southwest monsoon (May–September) followed by Northeast (November–March) and Inter monsoon (April and October) periods. In the meantime, the number of female T. gigas in 2009–2010 (Phase-1) was higher (38 crabs) than in 2010–2011 (Phase-2: 7 crabs) and 2012–2013 (Phase-3: 9 crabs) for which both increased overexploitation (for edible and fishmeal preparations) as well as anthropogenic disturbances in the vicinity (sand mining since 2009, land reclamation for wave breaker/parking lot constructions in 2011 and fishing jetty construction in 2013) are responsible. In this context, the physical infrastructure developments have altered the sediment close to nesting sites to be dominated by fine sand (2.5Xφ ) with moderately-well sorted (0.6–0.7σφ), very-coarse skewed (−2.4SKφ), and extremely leptokurtic (12.6Kφ) properties. Also, increased concentrations of Cadmium (from 4.2 to 13.6 mg kg−1) and Selenium (from 11.5 to 23.3 mg kg−1) in the sediment, and Sulphide (from 21 to 28 µg l−1) in the water were observed. In relation to the monsoonal changes affecting sheltered beach topography and sediment flux, the spawning crabs have shown a seasonal nest shifting behaviour in-between Sites I-III during 2009–2011. However, in 2012–2013, the crabs were mostly restricted to the areas (i.e., Sites I and II) with high

  15. Metabolic physiology of the Humboldt squid, Dosidicus gigas: Implications for vertical migration in a pronounced oxygen minimum zone

    NASA Astrophysics Data System (ADS)

    Rosa, Rui; Seibel, Brad A.

    2010-07-01

    The Humboldt (or jumbo) squid, Dosidicus gigas, is an active predator endemic to the Eastern Pacific that undergoes diel vertical migrations into a pronounced oxygen minimum layer (OML). Here, we investigate the physiological mechanisms that facilitate these migrations and assess the associated costs and benefits. Exposure to hypoxic conditions equivalent to those found in the OML (∼10 μM O 2 at 10 °C) led to a significant reduction in the squid’s routine metabolic rate (RMR), from 8.9 to 1.6 μmol O 2 g -1 h -1 ( p < 0.05), and a concomitant increase in mantle muscle octopine levels (from 0.50 to 5.24 μmol g -1 tissue, p < 0.05). Enhanced glycolitic ATP production accounted for only 7.0% and 2.8% at 10 °C and 20 °C, respectively, of the energy deficit that resulted from the decline in aerobic respiration. The observed metabolic suppression presumably extends survival time in the OML by conserving the finite stores of fermentable substrate and avoiding the accumulation of the deleterious anaerobic end products in the tissues. RMR increased significantly with temperature ( p < 0.05), from 8.9 (at 10 °C) to 49.85 μmol O 2 g -1 h -1 (at 25 °C) which yielded a Q10 of 2.0 between 10 and 20 °C and 7.9 between 20 and 25 °C ( p < 0.05). These results suggest that 25 °C, although within the normal surface temperature range in the Gulf of California, is outside this species’ normal temperature range. By following the scattering layer into oxygen-enriched shallow water at night, D. gigas may repay any oxygen debt accumulated during the daytime. The dive to deeper water may minimize exposure to stressful surface temperatures when most prey have migrated to depth during the daytime. The physiological and ecological strategies demonstrated here may have facilitated the recent range expansion of this species into northern waters where expanding hypoxic zones prohibit competing top predators.

  16. Effects of glyphosate-based herbicides on embryo-larval development and metamorphosis in the Pacific oyster, Crassostrea gigas.

    PubMed

    Mottier, Antoine; Kientz-Bouchart, Valérie; Serpentini, Antoine; Lebel, Jean Marc; Jha, Awadhesh N; Costil, Katherine

    2013-03-15

    Pesticides may be involved in oyster summer mortality events, not necessarily as a single causative agent but as an additional stressor. In this context, the present study aimed to assess the toxicity of glyphosate, its by-product, aminomethylphosphonic acid (AMPA) and two commercial formulations, Roundup Express(®) (R(EX)) and Roundup Allées et Terrasses(®) (R(AT)), containing glyphosate as the active ingredient, on the early life stages of the Pacific oyster, Crassostrea gigas. The embryotoxicity of these chemicals were quantified by considering both the rates of abnormalities and the arrested development or types of abnormalities in D-shaped larvae after 48 h exposure. The success of metamorphosis was examined in pediveliger larvae exposed for 24 h. Experiments involving both endpoints included range finding experiments for herbicide concentrations ranging from 0.1 to 100,000 μg L(-1). This range was then narrowed down in order to determine precise EC(50) values. Actual concentrations of the herbicide were determined at the beginning and after 48 h (embryotoxicity) and 24 h (metamorphosis) to evaluate the potential temporal variation in the concentrations. During embryo-larval development, no mortalities were recorded at any of the concentrations of glyphosate and AMPA, whereas no embryos or D-shaped larvae could be observed after exposure to 10,000 μg L(-1) of R(EX) or R(AT). Compared with the controls, no effects on embryo-larval development were recorded between 0.1 and 1000 μg L(-1), regardless of the chemical tested. Above a threshold, which varied according to the chemical used, the gradient of herbicide concentrations correlated with a gradient of severity of abnormality ranging from normal larvae to arrested development (an "old embryo" stage). The EC(50) values were 28,315 and 40,617 μg L(-1) for glyphosate and its metabolite, respectively, but much lowered values of 1133 and 1675 μg L(-1) for R(EX) and R(AT), respectively. Metamorphosis tests

  17. Contractor Logistics Support in the U.S. Air Force

    DTIC Science & Technology

    2009-01-01

    the Sacramento ALC at McClellan AFB . After the BRAC Commission voted in FY 1995 to close McClellan , the Air Force chose CLS for the F-117. The... Sacramento ALC at McClellan AFB would also have been the depot for the F-22. The original sustainment plan for organic sup- port was premised on a fleet of...major depots until the Base Realignment and Closure (BRAC) Commission in 1995 recommended closure of two ALCs.1 Kelly and McClellan AFBs closed in

  18. Real power regulation for the utility power grid via responsive loads

    DOEpatents

    McIntyre, Timothy J [Knoxville, TN; Kirby, Brendan J [Knoxville, TN; Kisner, Roger A

    2009-05-19

    A system for dynamically managing an electrical power system that determines measures of performance and control criteria for the electric power system, collects at least one automatic generation control (AGC) input parameter to at least one AGC module and at least one automatic load control (ALC) input parameter to at least one ALC module, calculates AGC control signals and loads as resources (LAR) control signals in response to said measures of performance and control criteria, propagates AGC control signals to power generating units in response to control logic in AGC modules, and propagates LAR control signals to at least one LAR in response to control logic in ALC modules.

  19. Effects of dietary α-lipoic acid, acetyl-l-carnitine, and sex on antioxidative ability, energy, and lipid metabolism in broilers.

    PubMed

    Jia, R; Bao, Y H; Zhang, Y; Ji, C; Zhao, L H; Zhang, J Y; Gao, C Q; Ma, Q G

    2014-11-01

    An experiment was conducted to evaluate the effects of dietary α-lipoic acid (LA), acetyl-l-carnitine (ALC), and sex on antioxidative ability, energy, and lipid metabolism in broilers. A total of 972 one-day-old broilers with equal sex were randomly assigned in a 3 × 3 × 2 factorial design using 3 LA, 3 ALC levels, and 2 sexes (6 replications, 9 birds/replication). The LA and ALC levels were 0, 50, and 100 mg/kg, respectively. Results showed that increased LA or ALC resulted in increased total antioxidant capacity and superoxide dismutase (SOD) and glutathione peroxidase (GSH-