Types and distribution of mucous cells of the abalone Haliotis ...

African Journals Online (AJOL)

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2012-05-08

May 8, 2012 ... Key words: Haliotis diversicolor; mucous cells, types, distribution. .... Figure 2. The shape of the mucous cells. O (oval or circle-like); c (cup- like); s ... (J) mucous cells at base of gill filaments, small cells, type II and type III; (K) a ...

Assessing the ecosystem effects of the abalone Haliotis midae from ...

African Journals Online (AJOL)

Assessing the ecosystem effects of the abalone Haliotis midae from its diet and foraging ... midae is commercially exploited and seriously threatened by overfishing. ... of the ecosystem because of associated changes in community structure. ... of this previously abundant herbivore on the south-west coast of South Africa, we ...

Proteomic analysis of muscle between hybrid abalone and parental lines Haliotis gigantea Reeve and Haliotis discus hannai Ino

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Di, G; Luo, X; You, W; Zhao, J; Kong, X; Ke, C

2015-01-01

To understand the potential molecular mechanism of heterosis, protein expression patterns were compared from hybrids of Haliotis gigantea (G) and Haliotis discus hannai (D) using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight/time-of-flight analyses. Expression differences were observed in muscle samples from the four groups with 673±21.0 stained spots for H. discus hannai ♀ × H. discus hannai ♂ (DD), 692±25.6 for H. gigantea ♀ × H. gigantea ♂ (GG), 679±16.2 for H. discus hannai ♀ × H. gigantea ♂ (DG) (F1 hybrid) and 700±19 for H. gigantea ♀ × H. discus hannai ♂ (GD) (F1 hybrid). Different 2-DE image muscle protein spots had a mirrored relationship between purebreds and the F1 hybrid, suggesting that all stained spots in F1 hybrid muscle were on 2-DEs from parents. DD and DG clustered together first, and then clustered with GD, whereas the distance of DD and GG was maximal according to hierarchical cluster analysis. We identified 136 differentially expressed protein spots involved in major biological processes, including energy metabolism and stress response. Most energy metabolism proteins were additive, and stress-induced proteins displayed additivity or over-dominance. In these 136 identified protein spots, hybrid offspring with additivity or over-dominance accounted for 68.38%. Data show that a proteomic approach can provide functional prediction of abalone interspecific hybridization. PMID:25669609

Removal of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests

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Merceron, NR.

2017-01-01

Full Text Available Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L., red squirrels (Sciurus vulgaris L., rats (Rattus sp., and wild boars (Sus scrofa L.. The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems.

Types and distribution of mucous cells of the abalone Haliotis ...

African Journals Online (AJOL)

The types and distribution of mucous cells of Haliotis diversicolorwere observed and analyzed using the alcian blue and periodic acid schiffs (AB-PAS) reaction and histological procedures. According to the color of the mucous cells, they were divided into four types: Type I, pure red; type II, pure blue; type III, purple reddish; ...

Hyperparasitism by the bacteriophage (Caudovirales) infecting Candidatus Xenohaliotis californiensis (Rickettsiales-like prokaryote) parasite of wild abalone Haliotis fulgens and Haliotis corrugata from the Peninsula of Baja California, Mexico.

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Cruz-Flores, Roberto; Cáceres-Martínez, Jorge; Muñoz-Flores, Monserrat; Vásquez-Yeomans, Rebeca; Hernández Rodriguez, Mónica; Ángel Del Río-Portilla, Miguel; Rocha-Olivares, Axayácatl; Castro-Longoria, Ernestina

2016-10-01

Candidatus Xenohaliotis californiensis (CXc) is a Rickettsiales-like prokaryote that is considered the causal agent of Withering Syndrome (WS), a chronic disease of abalone, from the west coast of North America and it is listed by the International Organization for Animal Health (OIE) as a reportable agent due to its pathogenicity. This bacterium in red abalone Haliotis rufescens, black abalone Haliotis cracherodii, and yellow abalone Haliotis corrugata from California, US and Baja California, Mexico has been found to be infected by a bacteriophage. To date, there is no information on the epizootiology of CXc and its bacteriophage in natural populations of abalone; furthermore, it is unknown if the bacteriophage was also present in CXc infecting blue abalone Haliotis fulgens. The objective of this study was to determine the distribution, prevalence and intensity of CXc, as well as to determine the distribution and prevalence of the bacteriophage and to study interactions between host sex and hyperparasitism in blue abalone and yellow abalone. Tissue samples were obtained from seven localities where the commercial capture of wild abalone is carried out. Samplings were conducted throughout the 2012-2013 capture seasons and a total of 182 blue abalone and 170 yellow abalone were obtained. The prevalence and intensity of CXc and the prevalence of the bacteriophage were determined by histology. The identity of CXc was confirmed by PCR, product sequence analysis and in situ hybridization while the identity of the bacteriophage was corroborated by TEM. The prevalence of CXc infected and uninfected by the bacteriophage was 80% in blue abalone and 62% in yellow abalone. Low infection intensities were found in 86% of blue abalone and 82% of yellow abalone. Infection intensity was significantly higher in undifferentiated yellow abalone. The bacteriophage in CXc showed a prevalence of 22% and 31% in blue abalone and yellow abalone respectively. These results show that CXc and

Impacts of the Invasive European Red Ant (Myrmica rubra (L.): Hymenoptera; Formicidae) on a Myrmecochorous System in the Northeastern United States.

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Gammans, Nicola; Drummond, Frank; Groden, Eleanor

2018-05-16

We investigated the impact of an invasive ant species from Europe, Myrmica rubra (L.), on a myrmecochorous system (seeds dispersed by ants) in its invaded range in North America. We assessed: 1) how M. rubra process the myrmecochorous diapsores (seeds and elaiosome as a single dispersal unit transported by ants) in comparison with native ants; 2) its preference for common native and invasive diaspore species relative to native ants; 3) how far they disperse diaspores in the field; and 4) the diaspore removal rate by invertebrates and vertebrates in infested areas compared to noninvaded sites. Field experiments demonstrated higher diaspore removal rates over a 10-min and 24-h period by M. rubra compared to native ants. M. rubra's diaspore dispersal distance was 40% greater compared to native ants. In two of three laboratory studies and one field study, there was no significant difference between the seed species which M. rubra and native ants selected. Our data suggest no long-term deleterious effects of M. rubra's invasion on diaspore dispersal in the Maine plant community that is comprised of both native and invasive species. This implies that M. rubra benefits from the myrmechorous plant species' diaspores by increasing their dispersal range away from the parent plant and potentially reducing seed predation. However, it is not known whether the fact that the native ant fauna and M. rubra are attracted to the same plant species' diaspores creates a high level of competition between the ants with deleterious effects on the native ant community.

Application of near-infrared spectroscopy for the rapid quality assessment of Radix Paeoniae Rubra

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Zhan, Hao; Fang, Jing; Tang, Liying; Yang, Hongjun; Li, Hua; Wang, Zhuju; Yang, Bin; Wu, Hongwei; Fu, Meihong

2017-08-01

Near-infrared (NIR) spectroscopy with multivariate analysis was used to quantify gallic acid, catechin, albiflorin, and paeoniflorin in Radix Paeoniae Rubra, and the feasibility to classify the samples originating from different areas was investigated. A new high-performance liquid chromatography method was developed and validated to analyze gallic acid, catechin, albiflorin, and paeoniflorin in Radix Paeoniae Rubra as the reference. Partial least squares (PLS), principal component regression (PCR), and stepwise multivariate linear regression (SMLR) were performed to calibrate the regression model. Different data pretreatments such as derivatives (1st and 2nd), multiplicative scatter correction, standard normal variate, Savitzky-Golay filter, and Norris derivative filter were applied to remove the systematic errors. The performance of the model was evaluated according to the root mean square of calibration (RMSEC), root mean square error of prediction (RMSEP), root mean square error of cross-validation (RMSECV), and correlation coefficient (r). The results show that compared to PCR and SMLR, PLS had a lower RMSEC, RMSECV, and RMSEP and higher r for all the four analytes. PLS coupled with proper pretreatments showed good performance in both the fitting and predicting results. Furthermore, the original areas of Radix Paeoniae Rubra samples were partly distinguished by principal component analysis. This study shows that NIR with PLS is a reliable, inexpensive, and rapid tool for the quality assessment of Radix Paeoniae Rubra.

Meningitis caused by Rhodotorula rubra in an human immunodeficiency virus infected patient

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Thakur K

2007-01-01

Full Text Available Rhodotorula spp . are common saprophytes but may be responsible for systemic infections in immunocompromised patients. Meningitis caused by Rhodotorula spp. in human immunodeficiency virus (HIV infected patients has been reported only rarely. We present a case of meningitis caused by Rhodotorula rubra in HIV infected patient. The presumptive diagnosis of cryptococcal meningitis was made on the basis of India ink preparation, Gram staining and latex agglutination test (LAT for cryptococcal antigen. The final diagnosis was confirmed by isolation of Rhodotorula rubra from cerebrospinal fluid on culture. LAT was considered false positive. Amphotericin B and 5-fluorocytosine were administered but the patient succumbed to his illness.

15-demethylisoplumieride acid, a new iridoid isolated from the bark of Plumeria rubra and latex of Himatanthus sucuuba; Acido 15-desmetilisoplumierideo, um novo iridoide isolado das cascas de Plumeria rubra e do latex de Himatanthus sucuuba

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Barreto, Alaide de Sa; Amaral, Ana Claudia F. [Fundacao Inst. Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Instituto de Tecnologia em Farmacos -Farmanguinhos. Lab. de Plantas Medicinais e Derivados; Silva, Jefferson Rocha de A. [Universidade Federal do Amazonas, Manaus, AM (Brazil). Dept. de Quimica]. E-mail: jrocha_01@ufam.edu.br; Schripsema, Jan [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, RJ (Brazil). Setor de Quimica de Produtos Naturais; Rezende, Claudia M.; Pinto, Angelo C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica

2007-09-15

Himatanthus sucuuba and Plumeria rubra are used in folk medicine in Brazil to treat various ailments. The isolation of the new iridoid 15-demethylisoplumieride from the bark of Plumeria rubra L. var. acutifolia (Ait) Woodson and latex of Himatanthus sucuuba (Spruce) Woodson is reported. Other iridoid glycosides were obtained from both plants. The structures of these substances were elucidated by spectral analysis and comparison with data already reported. (author)

Effects of Cornus mas L. and Morus rubra L. extracts on penicillin-induced epileptiform activity: an electrophysiological and biochemical study.

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Tubaş, Filiz; Per, Sedat; Taşdemir, Abdulkadir; Bayram, Ayşe Kaçar; Yıldırım, Mehmet; Uzun, Aydın; Saraymen, Recep; Gümüş, Hakan; Elmalı, Ferhan; Per, Hüseyin

2017-01-01

Traditionally, Morus rubra L. (Moraceae) (red mulberry) and Cornus mas L. (Cornacea) (cornelian cherry) fruits are eaten fresh and are also used in marmalades, juices, jam, natural dyes in Turkey and are believed to have beneficial effects in case of multiple health issues such as antipyretic, diarrhea and intestinal parasites. However, the effects of M. rubra and C. mas on epilepsy has not been known. This study evaluates the effects of M. rubra and C. mas extracts on penicillin-induced epileptiform activity. Sixty Wistar rats randomly divided into ten groups (n=6): control, sham, penicillin, penicillin+M. rubra extract (2.5, 5, 10, 20 mg/kg) and penicillin+C. mas extract (2.5, 5, 10 mg/kg). Epileptiform activity was induced by using penicillin (500 IU, i.c.) and electrocorticogram records (150 min) were obtained. Also, biochemical analysis in blood samples were evaluated. According to the electrocorticogram analysis, the effective dose was detected as 10 mg/kg for both C. mas and M. rubra. This dose decreased the spike frequencies of convulsions while amplitude wasn't changed by both substances. In erythrocyte studies, there were significant differences regarding nitric oxide in the control, sham and penicillin groups. There were significant differences regarding malondialdehyde in all groups. In the plasma, there were significant differences among groups regarding xanthine oxidase in the penicillin‑C. mas and penicillin‑M. rubra groups. There were differences regarding malondialdehyde in the penicillin-C. mas and M. rubra-C. mas groups. Both extracts reduced the frequency of epileptiform activity. After administration of the extracts malondialdehyde levels decreased also in both erythrocytes and plasma.

The negative impact of intentionally introduced Quercus rubra L. on a forest community

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Beata Woziwoda

2014-03-01

Full Text Available Some alien woody species used in commercial forestry become invasive and, as invaders, cause major problems in natural and semi-natural ecosystems. However, the deliberate introduction of aliens can bring unintended negative changes also within areas of their cultivation. This paper presents the effects of the intentional introduction of the North-American Quercus rubra in European mixed Scots pine-Pedunculate oak forests (POFs: Querco roboris-Pinetum (W. Mat. 1981 J. Mat. 1988. Phytosociological data from field research combined with GIS data analysis of the current distribution of Northern Red oak in the studied habitat were used to determine the composition and structure of forest communities in plots with and without Q. rubra participation.  The results show that Q. rubra significantly reduces native species richness and abundance, both in old-growth and in secondary (post-agricultural forests. Not one resident vascular plant benefits from the introduction of Northern Red oak and only a few are able to tolerate its co-occurrence. The natural restocking of all native woody species is also strongly limited by this alien tree.  The introduction of Northern Red oak significantly limits the environmental functions of the POF ecosystem and weakens its economic and social aspects. However, its further cultivation is justified from an economic point of view, as the essential function of the studied forests is commercial timber production, and the introduction of this fast growing alien tree supports the provisioning ecosystem services. A clear description of the level of trade-off between the accepted negative and positive effects of the introduction of Q. rubra on forest ecosystem services requires further interdisciplinary studies.

In vitro propagation of northern red oak (Quercus rubra L.)

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G. Vengadesan; Paula M. Pijut

2009-01-01

In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...

Adsorption recovery of thorium(IV) by Myrica rubra tannin and larch tannin immobilized onto collagen fibres

International Nuclear Information System (INIS)

Xuepin Liao; Li Li; Bi Shi

2004-01-01

Novel adsorbents which can concentrate Th(IV) in aqueous solution were prepared by immobilizing Myrica rubra tannin and larch tannin onto collagen fibre matrices. The adsorption capacities of the immobilized tannins to Th(IV) are related to temperature and pH value of the adsorption process. For example, when the initial concentration of Th(IV) was 116.0 mg x l -1 and the immobilized tannin was 100 mg, the adsorption capacities of immobilized Myrica rubra tannin and larch tannin were 55.98 mg Th(IV) x g -1 and 13.19 mg Th(IV) x g -1 , respectively at 303 K, and 73.67 mg Th(IV) x g -1 and 18.19 mg Th(IV) x g -1 at 323 K. It was also found that the higher adsorption capacity was obtained at higher pH value. The adsorption equilibrium data of the immobilized tannins for Th(IV) can be well fitted by the Langmuir model and the mechanism of the adsorption was found to be a chemical adsorption. In general, the adsorption capacity of immobilized Myrica rubra tannin to Th(IV) is significantly higher than that of immobilized larch tannin, probably due to the fact that the B ring of Myrica rubra tannin has a pyrogallol structure which has higher reaction activity with metal ions. The breakthrough point of the adsorption column of immobilized Myrica rubra tannin was at 33 bed volumes for the experimental system. The mass transfer coefficient of adsorption column determined by Adams-Bohart equation was 1.61 x 10 -4 l x mg -1 x min -1 . The adsorption column can be easily regenerated by 0.1 mol x l -1 HNO 3 solution, showing outstanding ability of concentrating Th(IV). (author)

Whole-genome sequencing reveals that Shewanella haliotis Kim et al. 2007 can be considered a later heterotypic synonym of Shewanella algae Simidu et al. 1990.

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Szeinbaum, Nadia; Kellum, Cailin E; Glass, Jennifer B; Janda, J Michael; DiChristina, Thomas J

2018-04-01

Previously, experimental DNA-DNA hybridization (DDH) between Shewanellahaliotis JCM 14758 T and Shewanellaalgae JCM 21037 T had suggested that the two strains could be considered different species, despite minimal phenotypic differences. The recent isolation of Shewanella sp. MN-01, with 99 % 16S rRNA gene identity to S. algae and S. haliotis, revealed a potential taxonomic problem between these two species. In this study, we reassessed the nomenclature of S. haliotis and S. algae using available whole-genome sequences. The whole-genome sequence of S. haliotis JCM 14758 T and ten S. algae strains showed ≥97.7 % average nucleotide identity and >78.9 % digital DDH, clearly above the recommended species thresholds. According to the rules of priority and in view of the results obtained, S. haliotis is to be considered a later heterotypic synonym of S. algae. Because the whole-genome sequence of Shewanella sp. strain MN-01 shares >99 % ANI with S. algae JCM 14758 T , it can be confidently identified as S. algae.

Morphology and molecular phylogeny of Paragorgia rubra sp. nov. (Cnidaria: Octocorallia), a new bubblegum coral species from a seamount in the tropical Western Pacific

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Li, Yang; Zhan, Zifeng; Xu, Kuidong

2017-07-01

A new species of bubblegum coral, Paragorgia rubra sp. nov., discovered from a seamount at a water depth of 373 m near the Yap Trench is studied using morphological and molecular approaches. Paragorgia rubra sp. nov. is the fourth species of the genus found in the tropical Western Pacific. The new gorgonian is red-colored, uniplanar, and measures approximately 530 mm high and 440 mm wide, with autozooids distributed only on one side of the colony. Paragorgia rubra sp. nov. is most similar to P. kaupeka Sánchez, 2005, but differs distinctly in the polyp ovals with large and compound protuberances (vs. small and simple conical protuberances) and the medullar spindles possessing simple conical protuberances (vs. compound protuberances). Moreover, P. rubra sp. nov. differs from P. kaupeka in the smaller length/width ratio of surface radiates (1.53 vs. 1.75). The genetic distance of the mtMutS gene between P. rubra sp. nov. and P. kaupeka is 0.66%, while the intraspecific distances within Paragorgia Milne-Edwards & Haime, 1857 except the species P. regalis complex are no more than 0.5%, further supporting the establishment of the new species. Furthermore, the ITS2 secondary structure of P. rubra sp. nov. is also different from those of congeners. Phylogenetic analyses indicate Paragorgia rubra sp. nov. and P. kaupeka form a clade, which branched early within Paragorgia and diversified approximately 15 Mya.

Anatomical and phenological implications of the relationship between Schinus polygama (Cav.) (Cabrera) and the galling insect Calophya rubra (Blanchard).

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Guedes, L M; Aguilera, N; Ferreira, B G; Becerra, J; Hernández, V; Isaias, R M S

2018-05-01

The success of galling insects could be determined by synchronisation with host plant phenology and climate conditions, ensuring suitable oviposition sites for gall induction and food resources for their survival. The anatomical, histochemical and phenological synchronisation strategies between Calophya rubra (Blanchard) (Hemiptera: Psylloidea) and its host, the evergreen plant Schinus polygama (Cav.) (Cabrera) (Anacardiaceae), in the Mediterranean climate of southern Chile was evaluated and compared to that of the congeneric C. cf. duvauae (Scott) from Brazil and closely related host plant S. engleri in a subtropical climate. Anatomical, histometric, histochemical and vegetative phenology studies of the stem and galls were conducted from June 2015 to December 2016. Based on the anatomical, histometric and histochemical analysis, the conical stem gall traits imply gains over the non-galled stem toward the galling insect survival, but the maintenance of phellem, secretory ducts and pith indicate conservative developmental traits that cannot be manipulated by C. rubra. Our results indicate that the conditions of the Mediterranean climate zone limit C. rubra immature activity during unfavourable periods, probably determining a diapause period and a univoltine life cycle, which are peculiarities of the S. polygama- C. rubra system. The synchronisation between development and seasonality confers peculiarities to the S. polygama- C. rubra system in the Mediterranean climate zone. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

Gustatory perception and metabolic utilization of sugars by Myrmica rubra ant workers

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Boevé, J-L.; Wäckers, F.L.

2003-01-01

The suitability of various nectar and honeydew sugars as a food source for the polyphagous ant species M. rubra (L.) was studied. The sugars used included monosaccharides (fructose, glucose, galactose, mannose, rhamnose), disaccharides (sucrose, maltose, trehalose, melibiose, lactose) and

Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758 (Gastropoda, Haliotidae

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I. Bravo Portela

2012-01-01

Full Text Available The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium.

Welke soort rood zwenkgras (Festuca rubra s.l.) komt voor in de jonge kustduinen van Voorne en die van overig Nederland?

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Freijsen, A.H.J.; Heeres, Els

1972-01-01

By common consent two taxa of Festuca rubra s.l. occur in sandy outer dunes along the N.W. European coasts. Festuca juncifolia St. Amans is considered to be a typical grass of Ammophiladunes. Festuca rubra subsp. arenaria (Osb.) Richt. could be found on almost fixed dunes. The only usable character

Crystallization and preliminary X-ray analysis of the NADPH-dependent 3-quinuclidinone reductase from Rhodotorula rubra

International Nuclear Information System (INIS)

Takeshita, Daijiro; Kataoka, Michihiko; Miyakawa, Takuya; Miyazono, Ken-ichi; Uzura, Atsuko; Nagata, Koji; Shimizu, Sakayu; Tanokura, Masaru

2009-01-01

The NADPH-dependent 3-quinuclidinone reductase from Rhodotorula rubra was expressed, purified, and crystallized and X-ray diffraction data of this crystal were collected to 2.2 Å resolution. (R)-3-Quinuclidinol is a useful compound that is applicable to the synthesis of various pharmaceuticals. The NADPH-dependent carbonyl reductase 3-quinuclidinone reductase from Rhodotorula rubra catalyzes the stereospecific reduction of 3-quinuclidinone to (R)-3-quinuclidinol and is expected to be utilized in industrial production of this alcohol. 3-Quinuclidinone reductase from R. rubra was expressed in Escherichia coli and purified using Ni-affinity and ion-exchange column chromatography. Crystals of the protein were obtained by the sitting-drop vapour-diffusion method using PEG 8000 as the precipitant. The crystals belonged to space group P4 1 2 1 2, with unit-cell parameters a = b = 91.3, c = 265.4 Å, and diffracted X-rays to 2.2 Å resolution. The asymmetric unit contained four molecules of the protein and the solvent content was 48.4%

Influence of papermill sludge on growth of Medicago sativa, Festuca rubra and Agropyron trachycaulum in gold mine tailings: A greenhouse study

International Nuclear Information System (INIS)

Green, Scott; Renault, Sylvie

2008-01-01

A greenhouse study was undertaken to determine the suitability of adding papermill sludge to neutral/alkaline gold mine tailings to improve the establishment of Festuca rubra, Agropyron trachycaulum and Medicago sativa. Festuca rubra root and shoot biomass and A. Trachycaulum shoot biomass were increased with papermill sludge amendment. The addition of papermill sludge and fertilizer drastically increased the shoot and root biomass of M. sativa (20-30 times) while A. trachycaulum and F. rubra showed a more moderate increase in growth. Photosynthetic pigment content of the leaves was higher in papermill sludge treatments than in the treatments without papermill sludge. The organic carbon content, macro-aggregate content and field capacity of the gold mine tailings were increased while the bulk density was decreased by the addition of papermill sludge. This study suggests that addition of papermill sludge and adequate fertilization can alleviate some of the adverse conditions of neutral/alkaline gold mine tailings. - Addition of papermill sludge and adequate fertilization of neutral gold mine tailings increased growth of Medicago sativa, Festuca rubra and Agropyron trachycaulum

The hydrogen peroxide impact on larval settlement and metamorphosis of abalone Haliotis diversicolor supertexta

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Zhang, Xiangjing; Yang, Zhihui; Cai, Zhonghua

2008-08-01

Abalone Haliotis diversicolor supertexta is an important economic mollusk. The settlement and metamorphosis are two critical stages during its development period, which has direct influence on abalone survival and production. The influence of reactive oxygen species (hydrogen peroxide) on abalone embryo and juvenile development were examined in this study. Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide. They had the best performance at 800 μmol/L. The concentration of 1 000 μmol/L or higher was toxic to the larvae, as the larvae could settle down only at benthic diatom plates without complete metamorphosis. In addition, H2O2 adding time was critical to the larval performance. 24h after two-day post-fertilization was proved to be the optimal adding time. In this paper, two action mechanisms of hydrogen peroxide are discussed: (1) hydrogen peroxide has direct toxicity to ciliated cells, thus cause apoptosis; (2) hydrogen peroxide, as a product from catecholamines’ autoxidation process in vivo, can reverse this process to produce neuro-transmitters to induce abalone metamorphosis.

Essential Oil from Myrica rubra Leaves Potentiated Antiproliferative and Prooxidative Effect of Doxorubicin and its Accumulation in Intestinal Cancer Cells.

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Ambrož, Martin; Hanušová, Veronika; Skarka, Adam; Boušová, Iva; Králová, Věra; Langhasová, Lenka; Skálová, Lenka

2016-01-01

Essential oil from the leaves of Myrica rubra, a subtropical Asian fruit tree traditionally used in folk medicines, has a significant antiproliferative effect in several intestinal cancer cell lines. Doxorubicin belongs to the most important cytostatics used in cancer therapy. The present study was designed to evaluate the effects of defined essential oil from M. rubra leaves on efficacy, prooxidative effect, and accumulation of doxorubicin in cancer cell lines and in non-cancerous cells. For this purpose, intestinal adenocarcinoma CaCo2 cells were used. Human fibroblasts (periodontal ligament) and a primary culture of rat hepatocytes served as models of non-cancerous cells. The results showed that the sole essential oil from M. rubra has a strong prooxidative effect in cancer cells while it acts as a mild antioxidant in hepatocytes. Combined with doxorubicin, the essential oil enhanced the antiproliferative and prooxidative effects of doxorubicin in cancer cells. At higher concentrations, synergism of doxorubicin and essential oil from M. rubra was proved. In non-cancerous cells, the essential oil did not affect the toxicity of doxorubicin and the doxorubicin-mediated reactive oxygen species formation. The essential oil increased the intracellular concentration of doxorubicin and enhanced selectively the doxorubicin accumulation in nuclei of cancer cells. Taken together, essential oil from M. rubra leaves could be able to improve the doxorubicin efficacy in cancer cells due to an increased reactive oxygen species production, and the doxorubicin accumulation in nuclei of cancer cells. Georg Thieme Verlag KG Stuttgart · New York.

Immunological changes in response to herpesvirus infection in abalone Haliotis laevigata and Haliotis rubra hybrids.

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Dang, Vinh T; Benkendorff, Kirsten; Corbeil, Serge; Williams, Lynette M; Hoad, John; Crane, Mark St J; Speck, Peter

2013-02-01

Australian abalone production has been affected by outbreaks of abalone viral ganglioneuritis (AVG) caused by a herpesvirus (AbHV). In this study, we undertook experimental transmission trials by immersion to study the abalone immune response to infection with AbHV. Representative cellular and humoural immune parameters of abalone, including total haemocyte count (THC), superoxide anion (SO) and antiviral activity against herpes simplex virus type 1 (HSV-1), were examined in apparently healthy (sub-clinical) and moribund abalone after challenge. In the early infection, sub-clinical stage (days 1-3), THC was found to increase significantly in infected abalone. TaqMan qPCR confirmed 20.5% higher viral load in moribund abalone compared to apparently healthy abalone, indicating that the abundance of AbHV within abalone is linked to their clinical signs. At the clinical stage of infection, THC was significantly lower in moribund abalone, but increased in AbHV-exposed but apparently healthy abalone, in comparison to non-infected controls. SO was reduced in all abalone that were PCR-positive for AbHV. THC and SO level were found to be negatively correlated with the presence of AbHV in abalone, but no effect of AbVH exposure was observed on the haemolymph antiviral activity. These results suggest that abalone mount an initial cellular immune response to AbHV infection, but this response cannot be sustained under high viral loads, leading to mortality. Copyright © 2012 Elsevier Ltd. All rights reserved.

Proteomic profiling of eggs from a hybrid abalone and its parental lines: Haliotis discus hannai Ino and Haliotis gigantea.

Science.gov (United States)

Di, Guilan; Luo, Xuan; Huang, Miaoqin; Chen, Jun; Kong, Xianghui; Miao, Xiulian; Ke, Caihuan

2015-12-01

Proteomic analysis was performed on the eggs of hybrid abalone and their corresponding parental lines. A total of 915 ± 19 stained protein spots were detected from Haliotis discus hannai♀ × H. discus hannai♂ (DD), 935 ± 16 from H. gigantea♀ × H. gigantea♂ (GG) and 923 ± 13 from H. gigantea♀ × H. discus hannai♂ (GD). The spots from DD and GD were clustered together. The distance between DD and GG was maximal by hierarchical cluster analysis. A total of 112 protein gel spots were identified; of these, 59 were abalone proteins. The proteins were involved in major biological processes including energy metabolism, proliferation, apoptosis, signal transduction, immunity, lipid metabolism, electron carrier proteins, protein biosynthesis and decomposition, and cytoskeletal structure. Three of 20 differential expression protein spots involved in energy metabolism exhibited as upregulated in GD, 13 spots exhibited additivity, and four spots exhibited as downregulated in the offspring. Eleven protein spots were expressed at the highest level in DD. The proteins involved in stress responses included superoxide dismutase, peroxiredoxin 6, thioredoxin peroxidase and glutathione-S-transferase. Two of seven differential expression protein spots involved in response to stress exhibited as upregulated in GD, three exhibited additivity, and two exhibited as downregulated. These results might suggest that proteomic approaches are suitable for the analysis of hybrids and the functional prediction of abalone hybridization. © 2015 Stichting International Foundation for Animal Genetics.

Laju Pertumbuhan Kerang Abalon Haliotis squamata Melalui Budidaya IMTA (Integrated Multi Trophic Aquaculture di Pantai Geger, Nusa Dua, Kabupaten Badung, Provinsi Bali

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Heny Hayati

2017-11-01

Full Text Available Abalone is an important non fishery commodity that has high potential value to be developed. Abalone culture still faces some problems, such as, relatively slow growth rate, low survival rate and causing environmental pollution. One of the efforts to tackle the problems, is applying the culture system that is environmental friendly, such as IMTA (Integrated Multitrophic Aquaculture. This research aims to identify the growth rate and survival rate of the abalone (Haliotis squamata and the suitability of chemical and physical environment parameter supporting the integration culture of abalone and seaweed (Gracilaria sp on different stocking density at Geger beach, Nusa Dua, Bali. This research was performed in 45 days using a complete randomized design method that consist of three treatments and three repetition. The result showed that the highet growth rate was on treat ment T3 which consisted of abalone (Haliotis squamata 40 individu and 10 bunches of seaweed (Gracilaria sp 100 grams weight/each individu (0.76%/day, then It followed by T2 treatment that was integrated with 10 bunches of seaweed 50 grams (0.71%/day. The lowest growth rate observed on treatment T1 (control/monoculture which consisted of 40 individu abalone (Haliotis squamata (0.59%/day. The highest survival rate found on treatment T2 (97.5% and followed by treatment T1 as control (94.5%, while the lowest number was found on treatment T3 (83.3%. Physical chemical water quality parameters showed that It supported the growth of both, abalone (Haliotis squamata and seaweed (Gracilaria sp. at Geger Beach, Nusa Dua, Badung Regency, Bali Province.

[Chile's experience with developing abalone (Haliotis spp.) farming: opportunities and challenges].

Science.gov (United States)

Enríquez, R; Villagrán, R

2008-04-01

Intensive abalone farming--specifically of the red abalone (Haliotis rufescens) and the green (or Japanese) abalone (Haliotis discus hannai)--has expanded rapidly in Chile since the late 1990s, and this article presents an overview of the challenges facing the industry and the factors which favour its development. At present, 100% of Chile's abalone enterprises farm the H. rufescens species, owing to its suitability for full-cycle culture. In the analysis of factors that facilitate the development of abalone farming in Chile, those that stand out include the characteristics of the aquatic ecosystem, existing entrepreneurial and professional skills, decisive government support in co-financing scientific and technological projects, infrastructure and associated services to support these development initiatives and a market where prices have remained stable and demand for abalone products has been steady. The greatest challenges facing intensive abalone farming in Chile are providing a constant supply of macroalgae for abalone feed and developing complementary feed, as well as updating current legislation on intensive abalone farming, strengthening producer associations and establishing health certification. The article discusses examples of the impact that native organisms can have on animals introduced into an aquatic ecosystem and the international transmission of agents such as withering syndrome and sabellid polychaete infestation disease, associated with the movement of abalone seeds and broodstock. The article also emphasises the importance of implementing the recommendations of the World Organisation for Animal Health.

Studies upon morhological and biological traits of Festuca rubra, subsp.fallax (Poaceae

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Bogusław Sawicki

2013-12-01

Full Text Available Observation and measurements of some traits of Festuca rubra L., subsp. fallax (Thuill. Hack. ecotypes were made in 1995-1997 using samples selected from natural habitats and collected in Grassland Experimental Station in Sosnowica. High differentiation of traits under study and their correlations were found. Valorized ecotypes are good material for new varieties breeding.

Characterization of genic microsatellite markers derived from expressed sequence tags in Pacific abalone ( Haliotis discus hannai)

Science.gov (United States)

Li, Qi; Shu, Jing; Zhao, Cui; Liu, Shikai; Kong, Lingfeng; Zheng, Xiaodong

2010-01-01

Simple sequence repeat (SSR) markers were developed from the expressed sequence tags (ESTs) of Pacific abalone ( Haliotis discus hannai). Repeat motifs were found in 4.95% of the ESTs at a frequency of one repeat every 10.04 kb of EST sequences, after redundancy elimination. Seventeen polymorphic EST-SSRs were developed. The number of alleles per locus varied from 2-17, with an average of 6.8 alleles per locus. The expected and observed heterozygosities ranged from 0.159 to 0.928 and from 0.132 to 0.922, respectively. Twelve of the 17 loci (70.6%) were successfully amplified in H. diversicolor. Seventeen loci segregated in three families, with three showing the presence of null alleles (17.6%). The adequate level of variability and low frequency of null alleles observed in H. discus hannai, together with the high rate of transportability across Haliotis species, make this set of EST-SSR markers an important tool for comparative mapping, marker-assisted selection, and evolutionary studies, not only in the Pacific abalone, but also in related species.

New ribosome-inactivating proteins with polynucleotide:adenosine glycosidase and antiviral activities from Basella rubra L. and bougainvillea spectabilis Willd.

Science.gov (United States)

Bolognesi, A; Polito, L; Olivieri, F; Valbonesi, P; Barbieri, L; Battelli, M G; Carusi, M V; Benvenuto, E; Del Vecchio Blanco, F; Di Maro, A; Parente, A; Di Loreto, M; Stirpe, F

1997-12-01

New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10(-10) M range, and by various cell lines, with IC50S in the 10(-8)-10(-6) M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237-282) with an LD50 (concentration that is 50% lethal) Bougainvillea spectabilis had an LD50 > 32 mg.kg-1. The N-terminal sequence of the two RIPs from Basella rubra had 80-93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.

The identification of growth lines in abalone shell using a nuclear microprobe

International Nuclear Information System (INIS)

Bettiol, A.A.; Yang, C.; Hawkes, G.P.; Jamieson, D.N.; Malmqvist, K.G.; Day, R.W.

1999-01-01

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn 2+ activated calcium carbonate. In this study we confirm Mn 2+ as the activator in both the spire and growth edge regions of the shell. The sensitivity of ionoluminescence to the co-ordination environment of the Mn 2+ activators in the shell allows for the spatial identification of the calcium carbonate polymorph responsible for the growth lines observed optically. Furthermore the detection and mapping of trace elements such as Mn and Sr with the PIXE technique enables comparisons to be made between calcite and aragonite biomineralized in the wild and under laboratory conditions

The identification of growth lines in abalone shell using a nuclear microprobe

Energy Technology Data Exchange (ETDEWEB)

Bettiol, A.A.; Yang, C.; Hawkes, G.P.; Jamieson, D.N. E-mail: dnj@physics.unimelb.edu.au; Malmqvist, K.G.; Day, R.W

1999-09-02

Ionoluminescence (IL) combined with particle induced X-ray emission (PIXE) imaging has been employed to identify intrinsic growth bands in the spire region, and extrinsic bands at the growth edge of Australian Black-lip abalone shell (Haliotis rubra). Previous studies using optical flood cathodoluminescence, scanning electron microscope cathodoluminescence (SEM-CL) and Raman spectroscopy on samples from the same population suggest that the visible luminescence is due to Mn{sup 2+} activated calcium carbonate. In this study we confirm Mn{sup 2+} as the activator in both the spire and growth edge regions of the shell. The sensitivity of ionoluminescence to the co-ordination environment of the Mn{sup 2+} activators in the shell allows for the spatial identification of the calcium carbonate polymorph responsible for the growth lines observed optically. Furthermore the detection and mapping of trace elements such as Mn and Sr with the PIXE technique enables comparisons to be made between calcite and aragonite biomineralized in the wild and under laboratory conditions.

High resolution electron backscatter diffraction (EBSD) data from calcite biominerals in recent gastropod shells.

Science.gov (United States)

Pérez-Huerta, Alberto; Dauphin, Yannicke; Cuif, Jean Pierre; Cusack, Maggie

2011-04-01

Electron backscatter diffraction (EBSD) is a microscopy technique that reveals in situ crystallographic information. Currently, it is widely used for the characterization of geological materials and in studies of biomineralization. Here, we analyze high resolution EBSD data from biogenic calcite in two mollusk taxa, Concholepas and Haliotis, previously used in the understanding of complex biomineralization and paleoenvironmental studies. Results indicate that Concholepas has less ordered prisms than in Haliotis, and that in Concholepas the level of order is not homogenous in different areas of the shell. Overall, the usefulness of data integration obtained from diffraction intensity and crystallographic orientation maps, and corresponding pole figures, is discussed as well as its application to similar studies. © 2010 Elsevier Ltd. All rights reserved.

Crystallization and preliminary X-ray analysis of the NADPH-dependent 3-quinuclidinone reductase from Rhodotorula rubra

Science.gov (United States)

Takeshita, Daijiro; Kataoka, Michihiko; Miyakawa, Takuya; Miyazono, Ken-ichi; Uzura, Atsuko; Nagata, Koji; Shimizu, Sakayu; Tanokura, Masaru

2009-01-01

(R)-3-Quinuclidinol is a useful compound that is applicable to the synthesis of various pharmaceuticals. The NADPH-dependent carbonyl reductase 3-­quinuclidinone reductase from Rhodotorula rubra catalyzes the stereospecific reduction of 3-quinuclidinone to (R)-3-quinuclidinol and is expected to be utilized in industrial production of this alcohol. 3-Quinuclidinone reductase from R. rubra was expressed in Escherichia coli and purified using Ni-affinity and ion-exchange column chromatography. Crystals of the protein were obtained by the sitting-drop vapour-diffusion method using PEG 8000 as the precipitant. The crystals belonged to space group P41212, with unit-cell parameters a = b = 91.3, c = 265.4 Å, and diffracted X-rays to 2.2 Å resolution. The asymmetric unit contained four molecules of the protein and the solvent content was 48.4%. PMID:19478454

Differentially-Expressed Genes Associated with Faster Growth of the Pacific Abalone, Haliotis discus hannai.

Science.gov (United States)

Choi, Mi-Jin; Kim, Gun-Do; Kim, Jong-Myoung; Lim, Han Kyu

2015-11-18

The Pacific abalone Haliotis discus hannai is used for commercial aquaculture in Korea. We examined the transcriptome of Pacific abalone Haliotis discus hannai siblings using NGS technology to identify genes associated with high growth rates. Pacific abalones grown for 200 days post-fertilization were divided into small-, medium-, and large-size groups with mean weights of 0.26 ± 0.09 g, 1.43 ± 0.405 g, and 5.24 ± 1.09 g, respectively. RNA isolated from the soft tissues of each group was subjected to RNA sequencing. Approximately 1%-3% of the transcripts were differentially expressed in abalones, depending on the growth rate. RT-PCR was carried out on thirty four genes selected to confirm the relative differences in expression detected by RNA sequencing. Six differentially-expressed genes were identified as associated with faster growth of the Pacific abalone. These include five up-regulated genes (including one specific to females) encoding transcripts homologous to incilarin A, perlucin, transforming growth factor-beta-induced protein immunoglobulin-heavy chain 3 (ig-h3), vitelline envelope zona pellucida domain 4, and defensin, and one down-regulated gene encoding tomoregulin in large abalones. Most of the transcripts were expressed predominantly in the hepatopancreas. The genes identified in this study will lead to development of markers for identification of high-growth-rate abalones and female abalones.

Differentially-Expressed Genes Associated with Faster Growth of the Pacific Abalone, Haliotis discus hannai

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Mi-Jin Choi

2015-11-01

Full Text Available The Pacific abalone Haliotis discus hannai is used for commercial aquaculture in Korea. We examined the transcriptome of Pacific abalone Haliotis discus hannai siblings using NGS technology to identify genes associated with high growth rates. Pacific abalones grown for 200 days post-fertilization were divided into small-, medium-, and large-size groups with mean weights of 0.26 ± 0.09 g, 1.43 ± 0.405 g, and 5.24 ± 1.09 g, respectively. RNA isolated from the soft tissues of each group was subjected to RNA sequencing. Approximately 1%–3% of the transcripts were differentially expressed in abalones, depending on the growth rate. RT-PCR was carried out on thirty four genes selected to confirm the relative differences in expression detected by RNA sequencing. Six differentially-expressed genes were identified as associated with faster growth of the Pacific abalone. These include five up-regulated genes (including one specific to females encoding transcripts homologous to incilarin A, perlucin, transforming growth factor-beta-induced protein immunoglobulin-heavy chain 3 (ig-h3, vitelline envelope zona pellucida domain 4, and defensin, and one down-regulated gene encoding tomoregulin in large abalones. Most of the transcripts were expressed predominantly in the hepatopancreas. The genes identified in this study will lead to development of markers for identification of high-growth-rate abalones and female abalones.

In vitro growth of flat aragonite crystals between the layers of the insoluble organic matrix of the abalone Haliotis laevigata

Science.gov (United States)

Gries, Katharina I.; Heinemann, Fabian; Rosenauer, Andreas; Fritz, Monika

2012-11-01

Nacre of abalone shells consists of aragonite platelets and organic material, the so-called organic matrix. During the growth process of the shell the aragonite platelets grow into a scaffold formed by the organic matrix. In this work we tried to mimic this growth process by placing a piece of the insoluble organic matrix (which is a part of the organic matrix) of the abalone Haliotis laevigata in a crystallization device which was flowed through by CaCl2 and NaHCO3 solutions. Using this setup amongst others flat aragonite crystals grow on the insoluble organic matrix. When investigating these crystals in a transmission electron microscope it is possible to recognize similarities to the structure of nacre, like the formation of mineral bridges and growth between layers of the insoluble organic matrix. These similarities are presented in this paper.

The distribution of heavy metals in the red abalone, haliotis rufescens, on the california coast

Energy Technology Data Exchange (ETDEWEB)

Anderlini, V.

1974-01-01

The gills, mantle, digestive gland, and foot muscle of 74 specimens of the red abalone, haliotis rufescens, from five localities on the california coast are analyzed for eight heavy metals. The distribution of these elements in the abalones appears to be non-normal. High lead concentrations in the la jolla-long beach area seem to reflect pollutant inputs; elsewhere lead levels appear to derive from natural sources. (1 graph, 1 map, 31 references, 1 table)

SNP discovery and High Resolution Melting Analysis from massive transcriptome sequencing in the California red abalone Haliotis rufescens.

Science.gov (United States)

Valenzuela-Muñoz, Valentina; Araya-Garay, José Miguel; Gallardo-Escárate, Cristian

2013-06-01

The California red abalone, Haliotis rufescens that belongs to the Haliotidae family, is the largest species of abalone in the world that has sustained the major fishery and aquaculture production in the USA and Mexico. This native mollusk has not been evaluated or assigned a conservation category even though in the last few decades it was heavily exploited until it disappeared in some areas along the California coast. In Chile, the red abalone was introduced in the 1970s from California wild abalone stocks for the purposes of aquaculture. Considering the number of years that the red abalone has been cultivated in Chile crucial genetic information is scarce and critical issues remain unresolved. This study reports and validates novel single nucleotide polymorphisms (SNP) markers for the red abalone H. rufescens using cDNA pyrosequencing. A total of 622 high quality SNPs were identified in 146 sequences with an estimated frequency of 1 SNP each 1000bp. Forty-five SNPs markers with functional information for gene ontology were selected. Of these, 8 were polymorphic among the individuals screened: Heat shock protein 70 (HSP70), vitellogenin (VTG), lysin, alginate lyase enzyme (AL), Glucose-regulated protein 94 (GRP94), fructose-bisphosphate aldolase (FBA), sulfatase 1A precursor (S1AP) and ornithine decarboxylase antizyme (ODC). Two additional sequences were also identified with polymorphisms but no similarities with known proteins were achieved. To validate the putative SNP markers, High Resolution Melting Analysis (HRMA) was conducted in a wild and hatchery-bred population. Additionally, SNP cross-amplifications were tested in two further native abalone species, Haliotis fulgens and Haliotis corrugata. This study provides novel candidate genes that could be used to evaluate loss of genetic diversity due to hatchery selection or inbreeding effects. Copyright © 2013 Elsevier B.V. All rights reserved.

Phenology, dichogamy, and floral synchronization in a northern red oak (Quercus rubra) seed orchard

Science.gov (United States)

Lisa W. Alexander; Keith E. Woeste

2016-01-01

We developed a novel scoring system to assess spring phenology in a northern red oak (Quercus rubra L.) clonal seed orchard. The system was used to score from 304 to 364 ramets for three reproductive seasons and to place clones into early, intermediate, and late phenology classes. Although the absolute number of clones in each phenological class...

Intraspecific Variation in Maximum Ingested Food Size and Body Mass in Varecia rubra and Propithecus coquereli

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Adam Hartstone-Rose

2011-01-01

Full Text Available In a recent study, we quantified the scaling of ingested food size (Vb—the maximum size at which an animal consistently ingests food whole—and found that Vb scaled isometrically between species of captive strepsirrhines. The current study examines the relationship between Vb and body size within species with a focus on the frugivorous Varecia rubra and the folivorous Propithecus coquereli. We found no overlap in Vb between the species (all V. rubra ingested larger pieces of food relative to those eaten by P. coquereli, and least-squares regression of Vb and three different measures of body mass showed no scaling relationship within each species. We believe that this lack of relationship results from the relatively narrow intraspecific body size variation and seemingly patternless individual variation in Vb within species and take this study as further evidence that general scaling questions are best examined interspecifically rather than intraspecifically.

Uptake of technetium from seawater by red abalone Haliotis rufescens

International Nuclear Information System (INIS)

Spies, R.B.

1975-01-01

Technetium accumulation from seawater by the abalone Haliotis rufescens was studied with 95 Tc. Concentration factors, uptake rates, steady state concentrations, and biological half-lives were determined experimentally for whole-body uptake. Whole-body concentration factors ranged from 135 to 205; biological half-life was 60 days. Changes in concentration factors were determined for six tissues during the uptake period. The highest activities were in the order of: digestive gland>gill>kidneys>heart>gonad>columnar muscle. Dead shells accumulated little activity compared to shells of living abalone. Gills and digestive system appear to be the routes of entry. Autoradiography shows that of the muscular tissues the outer edge of the foot and epipodium are the most active and the edible columnar muscle the least active. (author)

Regeneration of red oak (Quercus rubra L.) using shelterwood systems: Ecophysiology, silviculture and management recommendations

Science.gov (United States)

Daniel C. Dey; William C. parker

1996-01-01

There is considerable interest in developing relaible methods for regenerating red oak (Quercus rubra) in Ontario. Traditional silviculture methods have not been successful in maintaining the curent levels of oak growing stock. In this paper, we review the ecology, physiology and reproductive biology of red oak. This discussion stresses the...

Pityriasis Rubra Pilaris In The Indian Scenario

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Sarkar Rashmi

2002-01-01

Full Text Available Pityriasis rubra pilaris (PRP is an uncommon idiopathic papulosqamous disorder characterized by circumscribed follicular keratosis, palmoplantar keratoderma and frequently erythroderma. Seven patients of PRP (five females and two males in the age range of 2 to 50 years seen over a 2-year period are presented with their clinical features, triggering factors, associations and laboratory investigations. The clinical type of PRP was adult onset classical variety in three, juvenile circumscribed variety in two and adult onset atypical variety and juvenile classical variety in one each. The triggering factors were upper respiratory tract infection with nutritional deficiencies in two and folliculitis in one. The histopathology was consistent with PRP in all. Four patients were managed with oral vitamin A while one each was put on methotrexate, etretinate and topical steroids and they showed a good response. More number of cases should be studied over a longer period to substantiate the suggested immunologic mechanism of PRP.

Acantholytic Pityriasis Rubra Pilaris Associated with Imiquimod 3.75% Application

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Natasha Atanaskova Mesinkovska

2011-01-01

Full Text Available Imiquimod is an immunomodulator with both antitumor and antiviral properties. It is currently available in two cream formulations as Aldara (imiquimod 5% and the newly approved Zyclara (imiquimod 3.75%. Imiquimod has been associated with localized erythema, crusting, and scaling at the site of application. However, more severe generalized skin eruptions including erythema multiforme, psoriasis, and hyperpigmentation have been described. The newly approved imiquimod 3.75% cream is a presumably safer alternative due to its lower concentration. This paper describes the development of generalized acantholytic pityriasis rubra pilaris after the treatment of an actinic keratosis on the forehead with imiquimod 3.75% cream.

An analysis of phenotypic selection in natural stands of northern red oak (Quercus rubra L.)

Science.gov (United States)

Jeffery W. Stringer; David B. Wagner; Scott E. Schlarbaum; Daniel B. Houston

1995-01-01

Comparison of growth and stem quality parameters of 19-year-old progeny from superior and comparison trees indicates that rigorous phenotypic selection of trees in natural stands may not be an efficient method of parent tree selection for Quercus rubra L. Total tree height, dbh, number of branches in the butt log, fork height, and number of mainstem...

Comparison of polysaccharides of Haliotis discus hannai and Volutharpa ampullacea perryi by PMP-HPLC-MS(n) analysis upon acid hydrolysis.

Science.gov (United States)

Wang, Hongxu; Zhao, Jun; Li, Dongmei; Wen, Chengrong; Liu, Haiman; Song, Shuang; Zhu, Beiwei

2015-10-13

Haliotis discus hannai Ino (Haliotis) is a highly valued marine shellfish, and it is sometimes replaced by another cheaper Gastropoda mollusk, Volutharpa ampullacea perryi (Volutharpa). Polysaccharides from pleopods, viscera and gonads of these two gastropods were compared by analyzing the mono- and di-saccharides in their acid hydrolysates using high performance liquid chromatography-mass spectrometry (HPLC-MS(n)) after 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization. Disaccharide analysis revealed the distribution of uronic acid-containing polysaccharides (UACPs) in the biological samples. GlcA-(1 → 2)-Man, GlcA-(1 → 3)-GalN, and another disaccharide consisting of a hexuronic acid linked to a hexose were found in the hydrolysates, which indicated the existence of AGSP (abalone gonad sulfated polysaccharide) with the backbone composed of → 2)-α-Man(1 → 4)-β-GlcA(1 → repeating unit, AAP (abalone glycosaminoglycan-like polysaccharide) with the backbone of → 3)-GalNAc-(1 → 2)-GlcA-(1 → 3)-GalNAc-(1 → 4)-GlcA-(1 → repeating unit, and unidentified DS1P containing a hexuronic acid linked to a hexose unit, respectively. As shown by extracted ion chromatograms (XICs), AAP was the only UACP found in pleopods of the two gastropods; gonads and viscera of Haliotis contained DS1P and AGSP, while those of Volutharpa contained DS1P, AGSP as well as AAP. Monosaccharides in the acid hydrolysates were demonstrated in XICs by extracting their corresponding PMP derivative quasi-molecular ions one by one, and the results indicated the similar conclusion to the disaccharide analysis. Therefore, it could be concluded that polysaccharides from pleopods of the two gastropods are very similar, while those from their viscera and gonads differ greatly. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biokinetic behavior of Tc in the red abalone, Haliotis rufescens: a reassessment

International Nuclear Information System (INIS)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1981-01-01

The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments on other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalone exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by the abalone following a single feeding of labeled macroalga, Nereocystis pyrifera, is high (approx. 45%) and loss kinetics are similar to those observed following direct uptake from seawater

Essential oil from Myrica rubra leaves inhibits cancer cell proliferation and induces apoptosis in several human intestinal lines

Czech Academy of Sciences Publication Activity Database

Langhansová, Lenka; Hanusová, V.; Rezek, Jan; Stohanslová, B.; Ambrož, M.; Králová, V.; Vaněk, Tomáš; Lou, J.D.; Yun, Z.L.; Yang, J.; Skálová, L.

2014-01-01

Roč. 59, AUG 2014 (2014), s. 20-26 ISSN 0926-6690 R&D Projects: GA MŠk LH12165 Institutional support: RVO:61389030 Keywords : Myrica rubra * Essential oil * Antiproliferative effect Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.837, year: 2014

Essential Oil from Myrica rubra Leaves Potentiated Antiproliferative and Prooxidative Effect of Doxorubicin and its Accumulation in Intestinal Cancer Cells

Czech Academy of Sciences Publication Activity Database

Ambrož, M.; Hanušová, V.; Skarka, A.; Boušová, I.; Králová, V.; Langhansová, Lenka; Skálová, L.

2016-01-01

Roč. 82, 1/2 (2016), s. 89-96 ISSN 0032-0943 Institutional support: RVO:61389030 Keywords : Myrica rubra * Myricaceae * cytotoxicity Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 2.342, year: 2016

The influence of cultural treatments of the long-term survival and growth of planted Quercus rubra

Science.gov (United States)

James J. Zaczek; Kim C. Steiner

2011-01-01

A northern red oak (Quercus rubra L.) plantation testing 20 nursery stock and planting methods was used to evaluate treatments 3, 6, 10, and 17 years after planting. Survival over all treatments was 92 percent at age 3 and declined to 74 percent, 56 percent, and 39 percent at ages 6, 10, and 17, respectively. At age 17, survival was highest for...

Transcriptome characterization of the South African abalone Haliotis midae using sequencing-by-synthesis

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Roodt-Wilding Rouvay

2011-03-01

Full Text Available Abstract Background Worldwide, the genus Haliotis is represented by 56 extant species and several of these are commercially cultured. Among the six abalone species found in South Africa, Haliotis midae is the only aquacultured species. Despite its economic importance, genomic sequence resources for H. midae, and for abalone in general, are still scarce. Next generation sequencing technologies provide a fast and efficient tool to generate large sequence collections that can be used to characterize the transcriptome and identify expressed genes associated with economically important traits like growth and disease resistance. Results More than 25 million short reads generated by the Illumina Genome Analyzer were de novo assembled in 22,761 contigs with an average size of 260 bp. With a stringent E-value threshold of 10-10, 3,841 contigs (16.8% had a BLAST homologous match against the Genbank non-redundant (NR protein database. Most of these sequences were annotated using the gene ontology (GO and eukaryotic orthologous groups of proteins (KOG databases and assigned to various functional categories. According to annotation results, many gene families involved in immune response were identified. Thousands of simple sequence repeats (SSR and single nucleotide polymorphisms (SNP were detected. Setting stringent parameters to ensure a high probability of amplification, 420 primer pairs in 181 contigs containing SSR loci were designed. Conclusion This data represents the most comprehensive genomic resource for the South African abalone H. midae to date. The amount of assembled sequences demonstrated the utility of the Illumina sequencing technology in the transcriptome characterization of a non-model species. It allowed the development of several markers and the identification of promising candidate genes for future studies on population and functional genomics in H. midae and in other abalone species.

pemeliharaan yuwana abalon (Haliotis squamata TURUNAN F-1 SECARA TERKONTROL DENGAN JENIS pakan BERBEDA

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Bambang Susanto

2016-11-01

Full Text Available Abalon (Haliotis squamata merupakan jenis kekerangan yang mulai dikembangkan untuk dapat memenuhi permintaan pasar. Tingkat pertumbuhan abalon sangat lambat sehingga perlu dilakukan penelitian untuk memacu pertumbuhan. Tujuan penelitian ini adalah untuk mengetahui jenis pakan yang cocok dan dapat memacu pertumbuhan yuwana abalon. Biota uji yang digunakan adalah yuwana abalon dengan ukuran panjang cangkang awal 12,51 ± 1,27 mm, yang ditempatkan dalam wadah plastik berukuran 35 cm x 25 cm x13 cm, diisi dengan kepadatan 25 ekor/wadah. Perlakuan jenis pakan berbeda adalah (A pelet, (B pakan rumput laut (Gracilaria spp., dan (C kombinasi rumput laut dan pelet. Hasil penelitian menunjukkan bahwa pemberian jenis pakan berbeda memberikan pengaruh yang nyata (P<0,05 terhadap tingkat pertumbuhan panjang, lebar cangkang, dan bobot badan yuwana abalon turunan F-1. Abalone (Haliotis squamata is one of shellfish to develop for market demand. The growth of abalone is slow and this experiment was purposed to increase to find out the suitable kinds of feed to promote the growth of abalone juvenile in hatchery. The rearing of abalone juvenile was conducted in plastic boxes size of 35 cm x 25 cm x 13 cm, filled with density of 25 ind./box with initial shell length of 12.51 ± 1.27 mm. The experiment applied different kinds of feed, (A pellet, (B seaweed/Gracilaria spp., and (C combination of seaweed and pellet with three replicates in each treatment. The result of the experiment indicated that different feeding resulted in significant difference (P<0.05 on growth of width and length of shell and body weight abalone juvenile F-1 generation.

Initial characterization of receptors for molecules that induce the settlement and metamorphosis of Haliotis rufescens larvae

International Nuclear Information System (INIS)

Trapido-Rosenthal, H.G.

1985-01-01

Larvae of the marine gastropod mollusc Haliotis refescens are induced to undergo metamorphosis by γ-aminobutyric acid (GABA) and stereochemically related compounds. The most potent of these inducers is (-)-β-(parachlorophenyl)-GABA (baclofen). The inductive response exhibits positive cooperatively, and is subject to both facilitation (up-regulation) and habituation (down-regulation). Facilitation is brought about by diamino acids such as L-diaminopropionic acid (L-DAPA), and is characterized by decreased Hill coefficients (n/sub H/) and concentration requirements (EC 50 ) for inducers. Facilitation does not require the simultaneous presence of facilitating and inducing compounds, and the facilitated state is persistent. Larvae are capable of being up-regulated 2 days before they are capable of undergoing settlement and metamorphosis. Habituation can be brought about by exposure of pre-competent larvae to GABA 4 days prior to the attainment of competence; it is then slowly reversible. Larvae specifically bind tritiated (-)-baclofen in a manner that is saturable with both increasing time of exposure of larvae to, and with increasing concentration of, this compound. Specific binding can be competed for by unlabeled GABA-mimetic inducing molecules; the order of effectiveness of these molecules as competitors for specific binding correlates well with their effectiveness as inducers of metamorphosis. Facilitation of larvae by exposure to diamino acids does not alter their specific binding of tritiated (-)-baclofen. It is concluded from these findings that Haliotis larvae possess receptors for GABA-mimetic compounds

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

Energy Technology Data Exchange (ETDEWEB)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J. (Oregon State Univ., Newport (USA). Marine Science Center)

1982-10-01

The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater.

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

Energy Technology Data Exchange (ETDEWEB)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1982-10-01

The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labelled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, is approximately 45% and loss kinetics are similar to those observed following direct uptake from seawater.

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

International Nuclear Information System (INIS)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1982-01-01

The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater. (author)

Identification and characterization of miRNAs transcriptome in the South African abalone, Haliotis midae.

Science.gov (United States)

Picone, Barbara; Rhode, Clint; Roodt-Wilding, Rouvay

2017-02-01

Aquatic animal diseases are one of the most important limitations to the growth of aquaculture. miRNAs represent an important class of small ncRNAs able to modulate host immune and stress responses. In Mollusca, a large phylum of invertebrates, miRNAs have been identified in several species. The current preliminary study identified known miRNAs from the South African abalone, Haliotis midae. The economic and ecological importance of abalone makes this species a suitable model for studying and understanding stress response in marine gastropods. Furthermore, the identification of miRNA, represents an alternative and powerful tool to combat infectious disease. Copyright © 2016 Elsevier B.V. All rights reserved.

Pityriasis Rubra Pilaris: A Report of Two Cases and Literature Review

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Paravina Mirjana

2015-12-01

Full Text Available Pityriasis rubra pilaris (PRP is an idiopathic inflammatory hyperproliferative chronic dermatosis characterized by: perifollicular coalescing papules with central keratotic acuminate plugs gradually submerged in sheets of erythema; perifollicular erythema with islands of unaffected skin; palmoplantar keratoderma; diffuse desquamation which typically spreads from the head down to the feet. The cause of the condition is unknown, but possible etiological factors include: vitamin A deficiency, trauma, infections, autoimmune mechanisms, and malignancies. Taking into account different age of onset, clinical course, morphology and prognosis, there are six different types of the disease: two in adults (classical and atypical; three in children (classical, circumscribed and atypical; one in individuals infected with human immunodeficiency virus.

Vibrio harveyi Adheres to and Penetrates Tissues of the European Abalone Haliotis tuberculata within the First Hours of Contact

OpenAIRE

Cardinaud, Marion; Barbou, Annaïck; Capitaine, Carole; Bidault, Adeline; Dujon, Antoine Marie; Moraga, Dario; Paillard, Christine

2014-01-01

International audience; Vibrio harveyi is a marine bacterial pathogen responsible for episodic epidemics generally associated with massive mortalities in many marine organisms, including the European abalone Haliotis tuberculata. The aim of this study was to identify the portal of entry and the dynamics of infection of V. harveyi in the European abalone. The results indicate that the duration of contact be-tween V. harveyi and the European abalone influences the mortality rate and precocity. ...

PI3K-AKT signaling pathway is involved in hypoxia/thermal-induced immunosuppression of small abalone Haliotis diversicolor.

Science.gov (United States)

Sun, Yulong; Zhang, Xin; Wang, Guodong; Lin, Shi; Zeng, Xinyang; Wang, Yilei; Zhang, Ziping

2016-12-01

The PI3K-AKT signal pathway has been found to be involved in many important physiological and pathological processes of the innate immune system of vertebrates and invertebrates. In this study, the AKT (HdAKT) and PI3K (HdPI3K) gene of small abalone Haliotis diversicolor were cloned and characterized for the important status of PI3K and AKT protein in PI3K-AKT signaling pathway. The full length cDNAs of HdAKT and HdPI3K are 2126 bp and 6052 bp respectively, encoding proteins of 479 amino acids and 1097 amino acids, respectively. The mRNA expression level of fourteen genes in the PI3K-AKT signaling pathway were detected by quantitative real-time PCR. The results showed that all these fourteen genes were ubiquitously expressed in seven selected tissues. Meanwhile, HdAKT was expressed in haemocytes with the highest expression level (p abalone. The mRNA expression of these genes in gills, haemocytes and hepatopancreas was significantly down-regulated after the Vibrio parahaemolyticus stimulation with environment stimulation (thermal, hypoxia and thermal & hypoxia). These results indicate that the dual/multiple stresses defeat the immune system and lead to immunosuppression in abalone. PI3K-AKT signaling pathway may be involved in hypoxia/thermal-induced immunosuppression of small abalone Haliotis diversicolor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Myrica rubra leaves as a potential source of a dual 5-LOX/COX inhibitor

Czech Academy of Sciences Publication Activity Database

Langhansová, Lenka; Landa, Přemysl; Kutil, Zsófia; Tauchen, Jan; Maršík, Petr; Rezek, Jan; Lou, J.D.; Yun, Z.L.; Vaněk, Tomáš

2017-01-01

Roč. 28, č. 2 (2017), s. 343-353 ISSN 0954-0105 R&D Projects: GA MŠk LH12165; GA ČR(CZ) GA16-07193S Grant - others:OPPK(CZ) CZ.2.16/3.1.00/24014 Institutional support: RVO:61389030 Keywords : in-vitro * antiinflammatory activity * zucc. leaves * 5-lipoxygenase * sieb. * cyclooxygenase * constituents * antioxidants * myricitrin * metabolism * Myrica rubra * anti-inflammatory * cyclooxygenase 1 * cyclooxygenase 2 * 5-lipoxygenase Subject RIV: FR - Pharmacology ; Medidal Chemistry OBOR OECD: Medicinal chemistry Impact factor: 1.392, year: 2016

Anti-inflammatory, antinociceptive, and antipyretic effects of methanol extract of Cariniana rubra stem bark in animal models

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Edson N. Santos

2011-06-01

Full Text Available Cariniana rubra Miers (Lecythidaceae, popularly known as "jequitibá-vermelho'', is a large Brazilian tree whose bark is used in infusion and decoction for the treatment of inflammatory conditions. This study aims to assess the anti-inflammatory, antinociceptive, and antipyretic effects of Cariniana rubra methanolic stem bark extract (EM Cr using experimental animals. Anti-inflammatory activity of EM Cr was tested on carrageenan and dextran-induced rat paw edema, carrageenan-induced pleurisy in rats and acetic acid-increase vascular permeability in mice. Antinociceptive and antipyretic activities were evaluated using acetic acid-induced writhing, formalin and hot-plate tests in mice, as well as brewer's yeast-induced pyrexia in rats. The extract inhibitied carrageenan and dextran-induced edema, reduced exudate volume and leukocyte migration on the carrageenan-induced pleurisy and on the vascular permeability increase induced by acetic acid. The EM Cr inhibited nociception on the acetic acid-induced writhing and in the second phase of formalin test, and decreased rectal temperature. It was, however, inactive against thermal nociception.Phytochemical analysis with EM Cr showed the occurrence of saponins, triterpenes, sterols and phenolic compounds. Phytosterols (β-sitosterol, stigmasterol, pentacyclic triterpenes (α- and β-amyrin as a mixture, arjunolic acid, a phytosterol glycoside (sitosterol 3-O-β-D-glucopyranoside, and triterpenoid saponins (28-β-glucopyranosyl-23-O-acetyl arjunolic acid; 3-O-β-glucopyranosyl arjunolic acid and 28-O-[α-L-Rhamnopyranosyl-(1→2-β-glucopyranosyl]-23- O-acetyl arjunolic acid were the main identified compounds. It can be presumed that EM Cr caused their effects by inhibiting the liberation and/or action of different inflammatory mediators. These findings support the traditional use of Cariniana rubra preparations to treat inflammation.Cariniana rubra Miers (Lecythidaceae, popularmente conhecido como

Genetic diversity and stock identification of small abalone (Haliotis diversicolor) in Taiwan and Japan.

Science.gov (United States)

Hsu, Te-Hua; Gwo, Jin-Chywan

2017-01-01

Small abalone (Haliotis diversicolor) is a commercially valuable species for both fisheries and aquaculture. The production of annual farmed small abalone in Taiwan, once the highest in the world, has dramatically decreased in the past 15 years, and currently, the industry is close to collapse. Understanding the genetic diversity of small abalone and developing stock identification methods will be useful for genetic breeding, restoring collapsed stocks, managing stocks, and preventing illegal trade. We investigated 307 cultured and wild individuals from Taiwan, Japan, and Bali Island (Indonesia) by using the mitochondrial cytochrome c oxidase subunit I (COI) gene. Network analysis of mtDNA COI gene sequences revealed that the individuals collected from Taiwan, Japan, and Indonesia could be identified, and showed significant genetic divergence. In addition, the Indonesian population (Haliotis diversicolor squamata) was significantly different from the other populations and might need to be considered a separate species. We discovered a single nucleotide polymorphism marker in the mtDNA COI gene that can be used to distinguish the Taiwan population from the Japan population. We also developed a polymerase chain reaction-restriction fragment length polymorphism method for rapid detection. Furthermore, we could identify the cultured stocks, wild population, and hybrid stocks by using 6 microsatellites and amplified fragment length polymorphism. This study contributes useful tools for stock identification and the production of high-disease resistant small abalone strains (Japan × Taiwan or Taiwan × Japan). Efforts should be made to avoid unintentional random genetic mixing of the Taiwan population with the Japan population and subsequent breakdown of population differentiation, which impair local adaptation of the Taiwan wild population. Molecular markers revealed a split between the Taiwan and Japan populations, and the existence of a possible barrier to the free

Effects of rigor status during high-pressure processing on the physical qualities of farm-raised abalone (Haliotis rufescens).

Science.gov (United States)

Hughes, Brianna H; Greenberg, Neil J; Yang, Tom C; Skonberg, Denise I

2015-01-01

High-pressure processing (HPP) is used to increase meat safety and shelf-life, with conflicting quality effects depending on rigor status during HPP. In the seafood industry, HPP is used to shuck and pasteurize oysters, but its use on abalones has only been minimally evaluated and the effect of rigor status during HPP on abalone quality has not been reported. Farm-raised abalones (Haliotis rufescens) were divided into 12 HPP treatments and 1 unprocessed control treatment. Treatments were processed pre-rigor or post-rigor at 2 pressures (100 and 300 MPa) and 3 processing times (1, 3, and 5 min). The control was analyzed post-rigor. Uniform plugs were cut from adductor and foot meat for texture profile analysis, shear force, and color analysis. Subsamples were used for scanning electron microscopy of muscle ultrastructure. Texture profile analysis revealed that post-rigor processed abalone was significantly (P abalone meat was more tender than pre-rigor processed meat, and post-rigor processed foot meat was lighter in color than pre-rigor processed foot meat, suggesting that waiting for rigor to resolve prior to processing abalones may improve consumer perceptions of quality and market value. © 2014 Institute of Food Technologists®

Photosynthesis and xanthophyll cycle-mediated photoprotection in leaves of Quercus rubra and Q. alba seedlings of different light environments

Science.gov (United States)

Shi-Jean S. Sung; Dianpeng Xu; Paul P. Kormanik; Clanton C. Black

1997-01-01

Two and three years after the outplanting of 1-0 northern red oak (Quercus rubra, NRO) and white oak (Q. alba, WO) nursery stocks, the highest net photosynthetic rates (Amax) were observed from seedlings growing on a clearcut site, followed by those under a pine stand. Both NRO and WO...

Identification of a female spawn-associated Kazal-type inhibitor from the tropical abalone Haliotis asinina.

Science.gov (United States)

Wang, Tianfang; Nuurai, Parinyaporn; McDougall, Carmel; York, Patrick S; Bose, Utpal; Degnan, Bernard M; Cummins, Scott F

2016-07-01

Abalone (Haliotis) undergoes a period of reproductive maturation, followed by the synchronous release of gametes, called broadcast spawning. Field and laboratory studies have shown that the tropical species Haliotis asinina undergoes a two-week spawning cycle, thus providing an excellent opportunity to investigate the presence of endogenous spawning-associated peptides. In female H. asinina, we have isolated a peptide (5145 Da) whose relative abundance in hemolymph increases substantially just prior to spawning and is still detected using reverse-phase high-performance liquid chromatography chromatograms up to 1-day post-spawn. We have isolated this peptide from female hemolymph as well as samples prepared from the gravid female gonad, and demonstrated through comparative sequence analysis that it contains features characteristic of Kazal-type proteinase inhibitors (KPIs). Has-KPI is expressed specifically within the gonad of adult females. A recombinant Has-KPI was generated using a yeast expression system. The recombinant Has-KPI does not induce premature spawning of female H. asinina when administered intramuscularly. However it displays homomeric aggregations and interaction with at least one mollusc-type neuropeptide (LRDFVamide), suggesting a role for it in regulating neuropeptide endocrine communication. This research provides new understanding of a peptide that can regulate reproductive processes in female abalone, which has the potential to lead to the development of greater control over abalone spawning. The findings also highlight the need to further explore abalone reproduction to clearly define a role for novel spawning-associated peptide in sexual maturation and spawning. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

Root desiccation and drought stress responses of bareroot Quercus rubra seedlings treated with a hydrophilic polymer root dip

Science.gov (United States)

Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

2009-01-01

Root hydrogel, a hydrophilic polymer, has been used to improve transplanting success of bareroot conifer seedlings through effects on water holding capacity. We examined mechanisms by which Terra-sorb Fine Hydrogel reduces damage that occurs when roots of 1-year old, dormant northern red oak (Quercus rubra L.) were subjected to shortterm (1, 3, and 5...

Enzymatic properties and primary structures of two α-amylase isozymes from the Pacific abalone Haliotis discus hannai

OpenAIRE

Kumagai, Yuya; Satoh, Takuya; Inoue, Akira; Ojima, Takao

2013-01-01

Two α-amylase (EC 3.2.1.1) isozymes, HdAmy58 and HdAmy82, with approximate molecular masses of 58 kDa and 82 kDa, respectively, were isolated from the digestive fluid of the Pacific abalone Haliotis discus hannai. Optimal temperatures and pHs for HdAmy58 and HdAmy82 were at 30℃ and 6.7, and 30℃ and 6.1, respectively. Both enzymes similarly degraded starch, glycogen, and maltooligosaccharides larger than maltotriose producing maltose and maltotriose as the major degradation products. However, ...

Improving germination of red elm (Ulmus rubra), gray alder (Alnus incana), and buffaloberry (Shepherdia canadensis) seeds with gibberellic acid

Science.gov (United States)

Brenda Morales; Charles Barden; Cheryl Boyer; Jason Griffin; Lillian Fisher; Joni Thompson

2012-01-01

Red elm (Ulmus rubra), gray alder (Alnus incana), and buffaloberry (Shepherdia canadensis) are considered important plants for many Native American tribes in the United States. Native Americans use these 3 species for a variety of traditional and medicinal purposes. For example, red elm is still the preferred firewood for the cultural ceremonies of several tribes....

Rooting stem cuttings of northern red oak (Quercus rubra L.) utilizing hedged stump sprouts formed on recently felled trees

Science.gov (United States)

Matthew H. Gocke; Daniel J. Robinson

2010-01-01

The ability to root stem cuttings collected from hedged stump sprouts formed on recently felled trees was evaluated for 26 codominant northern red oak (Quercus rubra L.) trees growing in Durham County, NC. Sprouting occurred, the same year as felling, on 23 of the 26 tree stumps and sprout number was significantly and positively correlated with stump diameter. The...

Dry deposition of sulfate to Quercus rubra and Liriodendron tulipifera foliage

International Nuclear Information System (INIS)

Vandenberg, J.J.

1987-01-01

Estimates were made of the rate of dry deposition to red oak (Quercus rubra) and tulip poplar (Liriodendron tulipifera) foliage. In the laboratory, radioactive ammonium sulfate aerosols were generated in an exposure chamber. These aerosols were dry deposited onto leaves that were sequentially washed to examine the efficacy of washing procedures in removal of surface deposits. Over 90% of dry deposited sulfate was removed after a 30 second wash duration. Laboratory procedures also estimated the magnitude of foliar sulfur that leached into leaf wash solutions. The majority of laboratory leaves demonstrated no leaching of sulfur from the internal pool. However, some leaves showed significant sulfur leaching. It was concluded that leaching of internal sulfur was highly leaf specific. This indicated that each leaf used in field experiments needed to be individually examined for leaching

Genome sequence of pacific abalone (Haliotis discus hannai): the first draft genome in family Haliotidae.

Science.gov (United States)

Nam, Bo-Hye; Kwak, Woori; Kim, Young-Ok; Kim, Dong-Gyun; Kong, Hee Jeong; Kim, Woo-Jin; Kang, Jeong-Ha; Park, Jung Youn; An, Cheul Min; Moon, Ji-Young; Park, Choul Ji; Yu, Jae Woong; Yoon, Joon; Seo, Minseok; Kim, Kwondo; Kim, Duk Kyung; Lee, SaetByeol; Sung, Samsun; Lee, Chul; Shin, Younhee; Jung, Myunghee; Kang, Byeong-Chul; Shin, Ga-Hee; Ka, Sojeong; Caetano-Anolles, Kelsey; Cho, Seoae; Kim, Heebal

2017-05-01

Abalones are large marine snails in the family Haliotidae and the genus Haliotis belonging to the class Gastropoda of the phylum Mollusca. The family Haliotidae contains only one genus, Haliotis, and this single genus is known to contain several species of abalone. With 18 additional subspecies, the most comprehensive treatment of Haliotidae considers 56 species valid [ 1 ]. Abalone is an economically important fishery and aquaculture animal that is considered a highly prized seafood delicacy. The total global supply of abalone has increased 5-fold since the 1970s and farm production increased explosively from 50 mt to 103 464 mt in the past 40 years. Additionally, researchers have recently focused on abalone given their reported tumor suppression effect. However, despite the valuable features of this marine animal, no genomic information is available for the Haliotidae family and related research is still limited. To construct the H . discus hannai genome, a total of 580-G base pairs using Illumina and Pacbio platforms were generated with 322-fold coverage based on the 1.8-Gb estimated genome size of H . discus hannai using flow cytometry. The final genome assembly consisted of 1.86 Gb with 35 450 scaffolds (>2 kb). GC content level was 40.51%, and the N50 length of assembled scaffolds was 211 kb. We identified 29 449 genes using Evidence Modeler based on the gene information from ab initio prediction, protein homology with known genes, and transcriptome evidence of RNA-seq. Here we present the first Haliotidae genome, H . discus hannai , with sequencing data, assembly, and gene annotation information. This will be helpful for resolving the lack of genomic information in the Haliotidae family as well as providing more opportunities for understanding gastropod evolution. © The Authors 2017. Published by Oxford University Press.

Influence of overstory density on ecophysiology of red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings in central Ontario shelterwoods

Science.gov (United States)

William C. Parker; Daniel C. Dey

2008-01-01

A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...

Geographic Variation in Festuca rubra L. Ploidy Levels and Systemic Fungal Endophyte Frequencies.

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Serdar Dirihan

Full Text Available Polyploidy and symbiotic Epichloë fungal endophytes are common and heritable characteristics that can facilitate environmental range expansion in grasses. Here we examined geographic patterns of polyploidy and the frequency of fungal endophyte colonized plants in 29 Festuca rubra L. populations from eight geographic sites across latitudes from Spain to northernmost Finland and Greenland. Ploidy seemed to be positively and negatively correlated with latitude and productivity, respectively. However, the correlations were nonlinear; 84% of the plants were hexaploids (2n = 6x = 42, and the positive correlation between ploidy level and latitude is the result of only four populations skewing the data. In the southernmost end of the gradient 86% of the plants were tetraploids (2n = 4x = 28, whereas in the northernmost end of the gradient one population had only octoploid plants (2n = 8x = 56. Endophytes were detected in 22 out of the 29 populations. Endophyte frequencies varied among geographic sites, and populations and habitats within geographic sites irrespective of ploidy, latitude or productivity. The highest overall endophyte frequencies were found in the southernmost end of the gradient, Spain, where 69% of plants harbored endophytes. In northern Finland, endophytes were detected in 30% of grasses but endophyte frequencies varied among populations from 0% to 75%, being higher in meadows compared to riverbanks. The endophytes were detected in 36%, 30% and 27% of the plants in Faroe Islands, Iceland and Switzerland, respectively. Practically all examined plants collected from southern Finland and Greenland were endophyte-free, whereas in other geographic sites endophyte frequencies were highly variable among populations. Common to all populations with high endophyte frequencies is heavy vertebrate grazing. We propose that the detected endophyte frequencies and ploidy levels mirror past distribution history of F. rubra after the last glaciation

De novo characterisation of the greenlip abalone transcriptome (Haliotis laevigata) with a focus on the heat shock protein 70 (HSP70) family.

Science.gov (United States)

Shiel, Brett P; Hall, Nathan E; Cooke, Ira R; Robinson, Nicholas A; Strugnell, Jan M

2015-02-01

Abalone (Haliotis) are economically important molluscs for fisheries and aquaculture industries worldwide. Despite this, genomic resources for abalone and molluscs are still limited. Here we present a description and functional annotation of the greenlip abalone (Haliotis laevigata) transcriptome. We present a focused analysis on the heat shock protein 70 (HSP70) family of genes with putative functions affecting temperature stress and immunity. A total of ~38 million paired end Illumina reads were obtained, resulting in a Trinity assembly of 222,172 contigs with minimum length of 200 base pairs and maximum length of 33 kilobases. The 20,702 contigs were annotated with gene descriptions by BLAST. We created a program to maximise the number of functionally annotated genes, and over 10,000 contigs were assigned Gene ontologies (GO terms). By using CateGOrizer, immunity related GO terms for stressors such as heat, hypoxia, oxidative stress and wounding received the highest counts. Twenty-six contigs with homology to the HSP70 family of genes were identified. Ninety-one putative single-nucleotide polymorphisms were observed in the abalone HSP70 contigs. Eleven of these were considered non-synonymous. The annotated transcriptome described in this study will be a useful basis for future work investigating the genetic response of abalone to stress.

Alteration of foliar flavonoid chemistry induced by enhanced UV-B radiation in field-grown Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii.

Science.gov (United States)

Warren, Jeffrey M; Bassman, John H; Mattinson, D Scott; Fellman, John K; Edwards, Gerald E; Robberecht, Ronald

2002-03-01

Chromatographic analyses of foliage from several tree species illustrate the species-specific effects of UV-B radiation on both quantity and composition of foliar flavonoids. Pinus ponderosa, Quercus rubra and Pseudotsuga menziesii were field-grown under modulated ambient (1x) and enhanced (2x) biologically effective UV-B radiation. Foliage was harvested seasonally over a 3-year period, extracted, purified and the flavonoid fraction applied to a mu Bondapak/C(18) column HPLC system sampling at 254 nm. Total flavonoid concentrations in Quercus rubra foliage were more than twice (leaf area basis) that of the other species; Pseudotsuga menziesii foliage had intermediate levels and P. ponderosa had the lowest concentrations of total flavonoids. No statistically significant UV-B radiation-induced effects were found in total foliar flavonoid concentrations for any species; however, concentrations of specific compounds within each species exhibited significant treatment effects. Higher (but statistically insignificant) levels of flavonoids were induced by UV-B irradiation in 1- and 2-year-old P. ponderosa foliage. Total flavonoid concentrations in 2-year-old needles increased by 50% (1x ambient UV-B radiation) or 70% (2x ambient UV-B radiation) from that of 1-year-old tissue. Foliar flavonoids of Q. rubra under enhanced UV-B radiation tended to shift from early-eluting compounds to less polar flavonoids eluting later. There were no clear patterns of UV-B radiation effects on 1-year-old P. menziesii foliage. However, 2-year-old tissue had slightly higher foliar flavonoids under the 2x UV-B radiation treatment compared to ambient levels. Results suggest that enhanced UV-B radiation will alter foliar flavonoid composition and concentrations in forest tree species, which could impact tissue protection, and ultimately, competition, herbivory or litter decomposition.

Gene expression profiling in respond to TBT exposure in small abalone Haliotis diversicolor.

Science.gov (United States)

Jia, Xiwei; Zou, Zhihua; Wang, Guodong; Wang, Shuhong; Wang, Yilei; Zhang, Ziping

2011-10-01

In this study, we investigated the gene expression profiling of small abalone, Haliotis diversicolor by tributyltin (TBT) exposure using a cDNA microarray containing 2473 unique transcripts. Totally, 107 up-regulated genes and 41 down-regulated genes were found. For further investigation of candidate genes from microarray data and EST analysis, quantitative real-time PCR was performed at 6 h, 24 h, 48 h, 96 h and 192 h TBT exposure. 26 genes were found to be significantly differentially expressed in different time course, 3 of them were unknown. Some gene homologues like cellulose, endo-beta-1,4-glucanase, ferritin subunit 1 and thiolester containing protein II CG7052-PB might be the good biomarker candidate for TBT monitor. The identification of stress response genes and their expression profiles will permit detailed investigation of the defense responses of small abalone genes. Published by Elsevier Ltd.

Evidence of green fluorescent protein and growth hormone expression in red abalone (Haliotis rufescens larvae

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Mancilla-Sánchez Edgar

2017-02-01

Full Text Available The red abalone Haliotis rufescens is a highly appreciated mollusk in the national and international markets. Due to its natural over-exploitation and low growth rate, several genetic improvements were made, however special efforts are needed to increase its production. This study presents transgenic abalone’s larvae expressing green fluorescent protein (GFP fused to Cobia (Rachycentron canadum Growth Hormone (GH using sperm media transgenesis technique (SMT, pAcGFP1-N vector under the control of cytomegalovirus (CMV promoter. Sperms were exposed to three voltages (0.5, 0.75 and 1.0 Kv using a micropulser electroporator (Bio-Rad®. The highest GFP-GH expression average (40% was obtained in abalone larvae at 0.75 v. GFP and GH transgenes were positively detected by PCR, western blot and confocal microscope, respectively.

Philometra rubra (Nematoda: Philometridae) first description of the male from striped bass (Morone saxatilis) and implications for re-introduction of an extirpated population

Czech Academy of Sciences Publication Activity Database

Measures, L.; Moravec, František; Douglas, S.; Lair, S.

2017-01-01

Roč. 95, č. 5 (2017), s. 345-352 ISSN 0008-4301 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Philometra rubra * striped bass * Morone saxatilis * re-introduction * conservation Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 1.347, year: 2016

STIMULASI PERTUMBUHAN JUVENIL ABALON, Haliotis squamata DENGAN PEMBERIAN HORMON REKOMBINAN IKAN rElGH

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Fitriyah Husnul Khotimah

2017-01-01

Full Text Available Masalah yang paling utama dalam budidaya abalon tropis adalah pertumbuhan yang lambat. Penggunaan rElGH (recombinant giant grouper, Epinephelus lanceolatus growth hormone untuk menstimulasi pertumbuhan beberapa spesies ikan sudah dilakukan. Penelitian ini bertujuan untuk menguji akselerasi pertumbuhan juvenil abalon tropis, Haliotis squamata setelah diberi perlakuan perendaman hormon rekombinan ikan kerapu kertang, Epinephelus lanceolatus pada frekuensi yang berbeda. Ada empat perlakuan frekuensi perendaman rElGH yaitu 4, 9, 16 kali, dan tanpa perendaman (kontrol. Masing-masing perlakuan diulang tiga kali. Perendaman dilakukan selama tiga jam, dengan interval waktu empat hari. Kepadatan abalon tropis 100 ekor/L air laut yang mengandung 30 mg rElGH. Wadah untuk perendaman berupa beaker glass yang dilengkapi dengan aerasi. Penelitian dilakukan selama tujuh bulan. Hasil penelitian menunjukkan bahwa abalon tropis yang direndam rElGH dengan frekuensi empat kali menghasilkan pertumbuhan bobot tubuh dan panjang cangkang tertinggi dan berbeda nyata dengan perlakuan lainnya (P<0,05. Sintasan abalon tropis yang diberi perlakuan perendaman hormon rElGH lebih tinggi dibandingkan perlakuan kontrol. The most crucial problem in tropical abalone aquaculture is the slow growth of the species. Studies investigating the use of rElGH (recombinant giant grouper, Epinephelus lanceolatus growth hormone for promoting growth have been performed in various species. This research aimed to examine the growth acceleration of tropical abalone, Haliotis squamata juvenile after being treated in different immersion frequencies of recombinant giant grouper, Epinephelus lanceolatus growth hormone (rElGH. There were four treatments of rElGH immersion frequency: 4, 9, 16 times and without rElGH immersion (control. Each treatment was performed in triplicates. Immersion was performed for 3 hours, at 4-day intervals and a density of 100 tropical abalones in 1 L seawater containing 30

Toxicokinetics and biotransformation of p-nitrophenol in red abalone (Haliotis rufescens)

Energy Technology Data Exchange (ETDEWEB)

TenBrook, Patti L.; Kendall, Shellie M.; Viant, Mark R.; Tjeerdema, Ronald S

2003-02-26

Red abalone (Haliotis rufescens) were exposed to 3.6 {mu}M (0.5 ppm) {sup 14}C-labelled p-nitrophenol (PNP) for 24 h, then were allowed to depurate in clean seawater for another 24 h. Absorption, conditional uptake clearance and elimination rate constants were 0.12{+-}0.04 h{sup -1}, 3.2{+-}1.1 ml g{sup -1} h{sup -1} and 0.05{+-}0.02 h{sup -1}, respectively. The sigmoidal shape of the PNP uptake curve suggests a biphasic process. A whole-organism total concentration factor (TCF) of 2.37{+-}0.07 was determined from equilibrium tissue and water concentrations, with the highest concentration of PNP plus metabolites found in gill tissue (11.8{+-}0.2 nmol g{sup -1}, wet weight). Digestive gland, foot muscle and remaining body tissues accumulated 8.8{+-}0.9, 7.7{+-}0.6 and 7.5{+-}0.6 nmol g{sup -1} radiolabelled residues, respectively. Abalone depurated 91.6% of absorbed PNP within 24 h, of which 87.5{+-}3.1% was unmetabolized parent compound, 13.1{+-}3.1% was p-nitrophenylsulfate, 0.32{+-}0.09% was p-nitroanisole, and 0.14{+-}0.07% was p-acetamidophenol.

PEMATANGAN GONAD INDUK ABALON Haliotis squamata MELALUI PENGELOLAAN PAKAN

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Ibnu Rusdi

2016-11-01

Full Text Available Abalon merupakan hewan yang bersifat herbivora di alam memakan berbagai jenis makroalga. Penelitian ini bertujuan untuk mengetahui pengaruh berbagai makroalga sebagai pakan terhadap perkembangan gonad abalon Haliotis squamata. Dalam penelitian ini diterapkan 4 perlakuan pemberian pakan yaitu: (A Gracilaria sp., (B Ulva sp., (C Sargassum sp., (D Kombinasi Gracilaria sp. + Ulva sp. + Sargassum sp. (rasio 1:1:1. Rancangan yang digunakan adalah rancangan acak lengkap masing-masing dengan 3 ulangan. Induk-induk abalon dipelihara dalam 12 buah kontainer plastik berlubang ukuran 0,58 m x 0,39 m x 0,31 m dan ditempatkan dalam sebuah bak semen ukuran 3 m x 2 m x 1 m. Setiap kontainer berisi abalon sebanyak 10 ekor dengan ukuran awal rata-rata panjang cangkang dan bobot masing-masing 58,9±1,37 mm dan 36,1±4,06 g. Pakan diberikan dengan dosis 15%-20% dari bobot biomassa setiap 2 hari sekali. Pergantian air menggunakan sistem sirkulasi dengan debit 5-6 L/menit. Hasil penelitian menunjukkan bahwa rata-rata pertumbuhan bobot mutlak dan laju pertumbuhan bobot harian berbeda nyata (P<0,05 antar perlakuan. Tingkat kematangan gonad (TKG induk abalon pada hari ke-70 diperoleh TKG-III tertinggi dihasilkan pada perlakuan kombinasi Gracilaria + Ulva sp. + Sargassum sp. (P<0,05. Perlakuan pakan kombinasi Gracilaria sp. + Ulva sp. dan Sargassum sp. terlihat lebih sesuai dalam memacu pematangan gonad induk abalon H. squamata.  Abalone is a herbivorous animal which consumes various kinds of macroalgae in the wild. The aim of the study was to study the effects of various kinds of macroalgae on gonadal maturation of abalone, Haliotis squamata. The experiment applied four kinds of macroalgae i.e.: (A Gracilaria sp.; (B Ulva sp.; (C Sargassum sp.; and (D Combination of Gracilaria sp. + Ulva sp. + Sargassum sp. (ratio 1:1:1 as food for abalone broodstock. The experiment was arranged in complete random design with three replications. One cemented tank of 3 m x 2 m x 1 m in

KARAKTERISASI DAN EVALUASI POPULASI ABALON Haliotis squamata SECARA MOLEKULER, MORFOMETRIK, DAN BIOLOGI

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Gusti Ngurah Permana

2017-10-01

Full Text Available Abalon merupakan salah satu komoditas penting gastropoda laut. Tingginya permintaan abalon ini mengakibatkan menipisnya stok di alam. Oleh karena itu, upaya keberhasilan budidaya abalon perlu didukung oleh jenis unggul. Indikasi awal suatu jenis unggul dapat dilakukan dengan menganalisis potensi genetik yang dimiliki. Penelitian ini dilakukan dengan analisis gen 16S rRNA, karakter morfolologi, dan biologi dianalisis secara deskriptif dengan metode kajian pustaka. Hasil yang diperoleh menunjukkan keragaman inter populasi Haliotis squamata mendeteksi adanya tujuh haplotipe yang terbagi dalam dua kelompok. Penyertaan H. diversicolor sebagai outgroup dalam pengujian memperlihatkan bahwa populasi H. squamata dari Pulau Bali dan beberapa lokasi di Pulau Jawa berada dalam satu kelompok yang terpisah dengan outgroup. Hasil ini kongruen dengan analisis morfometrik terdapat perkembangan pertumbuhan cangkang yang asimetri pada populasi Banten. Pertumbuhan asimetri merupakan indikasi spesifik untuk populasi Banten atau merupakan gejala abnormalitas yang dapat diakibatkan oleh faktor penurunan kualitas genetik atau lingkungan. Karakter biologi terlihat proporsi daging dan gonad berbeda pada populasi Banten dengan indikasi adanya pertumbuhan asimetri. Rasio gonad dan daging populasi Banyuwangi berbeda nyata (P<0,05 dengan populasi lainnya. Abalone is arguably one of the highly valued and sought-after marine gastropods. However, the over-exploitation of this species has exhausted its wild stock. To overcome this challenge, the culture technique and management of this species must be established and continually improved. One of the ways is through producing superior broodstocks. An initial assessment of a genetically superior broodstock can be done using the potential genetic analysis. This recent research employed the analysis to study the species’ 16S rRNA gene. To complement the study, the morphometric and biological characteristics of the species were

KERAGAAN PERTUMBUHAN DAN REPRODUKSI ABALON Haliotis squamata Reeve (1846 TURUNAN KETIGA

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Gusti Ngurah Permana

2018-01-01

Full Text Available Pengamatan pertumbuhan dan reproduksi abalon Haliotis squamata dilakukan di hatcheri Balai Besar Riset Budidaya Laut dan Penyuluhan Perikanan (BBRBLPP Gondol, Bali. Tujuan dari penelitian ini untuk memperoleh informasi tentang keragaan pertumbuhan dan performansi reproduksi abalon turunan ketiga. Induk H. squamata turunan kedua hasil seleksi yang digunakan untuk menghasilkan benih turunan ketiga mempunyai ukuran panjang cangkang 6,5-7,0 cm. Benih dipelihara dalam bak beton berukuran 2,5 m x 1,2 m x 1,0 m yang diberikan feeding plate sebagai substrat penempelan dan dilengkapi dengan sistem aerasi dan sistem air mengalir. Pakan yang diberikan pada awal pemeliharaan adalah diatom jenis Nitzschia sp. dan Melosira sp. yang telah ditumbuhkan terlebih dahulu pada feeding plate sebelum penebaran benih. Benih F-3 dipelihara sampai menjadi calon induk untuk diamati perkembangan reproduksinya. Pengambilan sampel pertumbuhan dilakukan setiap 10 hari. Pengamatan reproduksi dilakukan pada saat abalon mulai tumbuh gonad sampai matang gonad stadia-III. Hasil penelitian menunjukkan bahwa pertumbuhan abalon sangat dipengaruhi ketersediaan pakan pada plate terutama pada hari ke-50. Proporsi jantan-betina abalon F-3 (3,3:1 meningkat dibandingkan dengan F-0 dari alam (2,5:1 menunjukkan ketidakseimbangan jumlah individu yang dapat disebabkan oleh tekanan seleksi. Abalon turunan ketiga pada umur 16 bulan mulai matang gonad dan dapat digunakan sebagai induk untuk pemijahan. Observation on the growth and reproduction development of Haliotis squamata had been undertaken in the hatchery of the Institute for Mariculture Research and Development (IMRAD Gondol, Bali. The research was aimed to study of the growth and reproduction performance of filial-3 abalone in supporting seed production in hatchery. Larvae were obtained from natural spawning of filial-2 abalone broodstock with the length shell of 6.5-7.0 cm in the hatchery. Larvae were reared in 2.5 m x 1.2 m x 1.0 m

Nitrogen fixation and growth response of Alnus Rubra following fertiliztion with urea or biosolids Fixação de nitrogênio e crescimento de Alnus Rubra fertilização com uréia ou biosólidos

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Linda S. Gaulke

2006-08-01

Full Text Available Nitrogen fertilization of forests using biosolids offers a potentially environmentally friendly means to accelerate tree growth. This field study was designed to analyze the effects of nitrogen fertilization on the symbiotic, nitrogen (N-fixing relationship between Alnus rubra Bong. (red alder and Frankia. Anaerobically digested, class B biosolids and synthetic urea (46% N were applied at rates of 140, 280 and 560 kg ha-1 available N to a well-drained, sandy, glacial outwash soil in the Indianola series (mixed, mesic Dystric Xeropsamments. Plots were planted with A. rubra seedlings. At the end of each of two growing seasons trees were harvested and analyzed for the rate of N fixation (as acetylene reduction activity, biomass and foliar N. At year 1, there was no N fixation for trees grown with urea amendments, but control (17 µmol C2H4 g-1 hr-1 and biosolids (26-45 µmol C2H4 g-1 hr-1 trees were fixing N. At the end of year 2, all trees in all treatments were fixing N (7 µmol C2H4 g-1 hr-1, 4-16 µmol C2H4 g-1 hr-1, and 20-29 µmol C2H4 g-1 hr-1 for control, urea and biosolids respectively. Trees grown with biosolids amendments were larger overall (year 1 shoot biomass 10 g, 5 g, and 23 g for control, urea, and biosolids respectively, year 2 shoot biomass 50 g, 51 g, and 190 g for control, urea, and biosolids respectively with higher concentrations of foliar N for both years of the study (year 1 foliar N 26 g kg-1, 27 g kg-1, and 40 g kg-1 for control, urea, and biosolids respectively, year 2 foliar N 17 g kg-1, 19 g kg-1, and 23 g kg-1 for control, urea, and biosolids respectively. Trees grown with urea amendments appeared to use the urea N over Frankia supplied N, whereas the biosolids trees appeared to be able to use both N in biosolids and N from Frankia. The results from this study indicated that the greater growth of A. rubra may have been responsible for the observed higher N demand. Biosolids may have supplied other nutrients to the

Metabolic responses of Haliotis diversicolor to Vibrio parahaemolyticus infection.

Science.gov (United States)

Lu, Jie; Shi, Yanyan; Cai, Shuhui; Feng, Jianghua

2017-01-01

Vibrio parahemolyticus is a devastating bacterial pathogen that often causes outbreak of vibriosis in abalone Haliotis diversicolor. Elucidation of metabolic mechanisms of abalones in responding to V. parahemolyticus infection is essential for controlling the epidemic. In this work, 1 H NMR-based metabolomic techniques along with correlation and network analyses are used to investigate characteristic metabolites, as well as corresponding disturbed pathways in hepatopancreas and gill of H. diversicolor after V. parahemolyticus infection for 48 h. Results indicate that obvious gender- and tissue-specific metabolic responses are induced. Metabolic responses in female abalones are more clearly observed than those in males, which are primarily manifested in the accumulation of branched-chain amino acids and the depletion of organic osmolytes (homarine, betaine and taurine) in the infected gills of female abalones, as well as in the depletion of glutamate, branched-chain and aromatic amino acids in the infected hepatopancreases of female abalones. Moreover, based on major metabolic functions of the characteristic metabolites, we have found that V. parahemolyticus infection not only cause the disturbance in energy metabolism, nucleotide metabolism and osmotic balance, but also induce oxidative stress, immune stress and neurotoxic effect in different tissues with various mechanisms. Our study provides details of metabolic responses of abalones to V. parahemolyticus infection and will shed light on biochemical defence mechanisms of male and female hosts against pathogen infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of chemical cues on larval survival, settlement and metamorphosis of abalone Haliotis asinina

Science.gov (United States)

Wang, Xiaobing; Bai, Yang; Huang, Bo

2010-11-01

Low larval survival, poor settlement, and abnormal metamorphosis are major problems in seed production of donkey-ear abalone Haliotis asinina. We examined the effects of chemical cues including epinephrine, nor-epinephrine, and serotonin on larval survival, settlement, and metamorphosis in order to determine the possibility of using these chemicals to induce the problems. The results show that epinephrine could enhance metamorphosis rate at 10-6 mol/L only but higher concentrations (10-3-10-4 mol/L); and nor-epinephrine could inhibit the performance significantly, and serotonin could increase significantly the performance at a wide-range concentration (10-3-10-6 mol/L). Treatment with serotonin at 10-5 mol/L for 72 hours resulted in the highest settlement rate (42.2%) and survival rate (49.3%), while at 10-4 mol/L for 72 hours resulted in the highest metamorphosis rate (38.8%). Therefore, serotonin may be used as a fast metamorphosis inducer in abalone culture.

[Differences between cold and hot natures of processed Radix ginseng rubra and Panax quinquefolius L. based upon mice temperature tropism].

Science.gov (United States)

Zhang, Xue-Ru; Zhao, Yan-Ling; Wang, Jia-Bo; Zhou, Can-Ping; Liu, Ta-Si; Zhao, Hai-Ping; Ren, Yong-Shen; Yan, Dan; Xiao, Xiao-He

2009-07-28

To establish an objective method to estimate the disparity between the cold and hot natures on the basis of an intrinsic correlation between temperature tropism of mice and the cold and hot natures of Chinese medicines. Male KM mice were randomly divided into 7 groups of 6 each, namely the normal group (NM), the weak model group (WM), the strong model group (SM), the weak model plus Radix ginseng rubra group (WM + RG), the weak model plus Panax quinquefolius L. group (WM + PQ), the strong model plus Radix ginseng rubra group (SM + RG) and the strong model plus Panax quinquefolius L. group (SM +PQ). The specific herbal drugs were administered intragastricly. To induce the weak model, mice were fed with a limited supply of feed and forced to swim in cold water until almost drowning while the strong model induced by feeding a high-protein diet with an unlimited feed access. The doses of Radix ginseng rubra and Panax quinquefolius L. were 35 mg/g of body weight per day (counted by the quantity of crude material) and lasting for seven days. The NM and model groups without dosing were intragastricly administered with physiological saline of the same volume to the dosing groups. The percentage of the remaining time of mouse on a high temperature (40 degrees C) pad to the total monitoring time was recorded by a self-designed intelligent animal behavior monitoring system. Meanwhile, the drinking volume of mice in each group was measured. Immediately after experiment, the activities of Na(+)K(+)-ATPase and superoxide dismutase (SOD) in liver tissue were measured by assay kits of phosphorus and xanthine oxidase methods respectively. The features of deficient and cold symptom, such as fatigue, stagnant weight growth, decreased water intake, cold limbs and tail etc, were observed in WM group. And the features of heat symptom, such as increased weight and water intake, hyperactivity etc, were observed in SM group. The percentage of time that the mouse remained on 40 degrees C

Preliminary genetic linkage map of the abalone Haliotis diversicolor Reeve

Science.gov (United States)

Shi, Yaohua; Guo, Ximing; Gu, Zhifeng; Wang, Aimin; Wang, Yan

2010-05-01

Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio ( P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively.

Involvement of Antizyme Characterized from the Small Abalone Haliotis diversicolor in Gonadal Development.

Science.gov (United States)

Li, Wei-Dong; Huang, Min; Lü, Wen-Gang; Chen, Xiao; Shen, Ming-Hui; Li, Xiang-Min; Wang, Rong-Xia; Ke, Cai-Huan

2015-01-01

The small abalone Haliotis diversicolor is an economically important mollusk that is widely cultivated in Southern China. Gonad precocity may affect the aquaculture of small abalone. Polyamines, which are small cationic molecules essential for cellular proliferation, may affect gonadal development. Ornithine decarboxylase (ODC) and antizyme (AZ) are essential elements of a feedback circuit that regulates cellular polyamines. This paper presents the molecular cloning and characterization of AZ from small abalone. Sequence analysis showed that the cDNA sequence of H. diversicolor AZ (HdiODCAZ) consisted of two overlapping open reading frames (ORFs) and conformed to the +1 frameshift property of the frame. Thin Layer chromatography (TLC) analysis suggested that the expressed protein encoded by +1 ORF2 was the functional AZ that targets ODC to 26S proteasome degradation. The result demonstrated that the expression level of AZ was higher than that of ODC in the ovary of small abalone. In addition, the expression profiles of ODC and AZ at the different development stages of the ovary indicated that these two genes might be involved in the gonadal development of small abalone.

Toxicokinetics and biotransformation of p-nitrophenol in red abalone (Haliotis rufescens)

International Nuclear Information System (INIS)

TenBrook, Patti L.; Kendall, Shellie M.; Viant, Mark R.; Tjeerdema, Ronald S.

2003-01-01

Red abalone (Haliotis rufescens) were exposed to 3.6 μM (0.5 ppm) 14 C-labelled p-nitrophenol (PNP) for 24 h, then were allowed to depurate in clean seawater for another 24 h. Absorption, conditional uptake clearance and elimination rate constants were 0.12±0.04 h -1 , 3.2±1.1 ml g -1 h -1 and 0.05±0.02 h -1 , respectively. The sigmoidal shape of the PNP uptake curve suggests a biphasic process. A whole-organism total concentration factor (TCF) of 2.37±0.07 was determined from equilibrium tissue and water concentrations, with the highest concentration of PNP plus metabolites found in gill tissue (11.8±0.2 nmol g -1 , wet weight). Digestive gland, foot muscle and remaining body tissues accumulated 8.8±0.9, 7.7±0.6 and 7.5±0.6 nmol g -1 radiolabelled residues, respectively. Abalone depurated 91.6% of absorbed PNP within 24 h, of which 87.5±3.1% was unmetabolized parent compound, 13.1±3.1% was p-nitrophenylsulfate, 0.32±0.09% was p-nitroanisole, and 0.14±0.07% was p-acetamidophenol

Fungal endophyte (Epichloë festucae alters the nutrient content of Festuca rubra regardless of water availability.

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Beatriz R Vázquez-de-Aldana

Full Text Available Festuca rubra plants maintain associations with the vertically transmitted fungal endophyte Epichloë festucae. A high prevalence of infected host plants in semiarid grasslands suggests that this association could be mutualistic. We investigated if the Epichloë-endophyte affects the growth and nutrient content of F. rubra plants subjected to drought. Endophyte-infected (E+ and non-infected (E- plants of two half-sib lines (PEN and RAB were subjected to three water availability treatments. Shoot and root biomass, nutrient content, proline, phenolic compounds and fungal alkaloids were measured after the treatments. The effect of the endophyte on shoot and root biomass and dead leaves depended on the plant line. In the PEN line, E+ plants had a greater S:R ratio than E-, but the opposite occurred in RAB. In both plant lines and all water treatments, endophyte-infected plants had greater concentrations of N, P and Zn in shoots and Ca, Mg and Zn in roots than E- plants. On average, E+ plants contained in their shoots more P (62%, Zn (58% and N (19% than E- plants. While the proline in shoots increased in response to water stress, the endophyte did not affect this response. A multivariate analysis showed that endophyte status and plant line impose stronger differences in the performance of the plants than the water stress treatments. Furthermore, differences between PEN and RAB lines seemed to be greater in E- than in E+ plants, suggesting that E+ plants of both lines are more similar than those of their non-infected version. This is probably due to the endophyte producing a similar effect in both plant lines, such as the increase in N, P and Zn in shoots. The remarkable effect of the endophyte in the nutrient balance of the plants could help to explain the high prevalence of infected plants in natural grasslands.

Screening the wetland plant species Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc and comparison with Eriophorum angustifolium and Festuca rubra Merlin

Energy Technology Data Exchange (ETDEWEB)

Matthews, David J. [Wetland Ecology Research Group, Department of Botany, University College Dublin, Belfield, Dublin 4 (Ireland)]. E-mail: davematt00@hotmail.com; Moran, Bridget M. [Wetland Ecology Research Group, Department of Botany, University College Dublin, Belfield, Dublin 4 (Ireland); Otte, Marinus L. [Wetland Ecology Research Group, Department of Botany, University College Dublin, Belfield, Dublin 4 (Ireland)

2005-03-01

Several wetland plant species appear to have constitutive metal tolerance. In previous studies, populations from contaminated and non-contaminated sites of the wetland plants Typha latifolia, Phragmites australis, Glyceria fluitans and Eriophorum angustifolium were found to be tolerant to high concentrations of metals. This study screened three other species of wetland plants: Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc. The degree of tolerance was compared to known zinc-tolerant E. angustifolium and Festuca rubra Merlin. It was found that A. plantago-aquatica and P. arundinacea did not posses innate tolerance to zinc, but that C. rostrata was able to tolerate elevated levels of zinc, at levels comparable to those tolerated by E. angustifolium and F. rubra Merlin. The findings support the theory that some wetland angiosperm species tend to be tolerant to exposure to high levels of metals, regardless of their origin. - Some wetland angiosperms are tolerant to high concentrations of metals, regardless of conditions in the plants' natural habitat.

Screening the wetland plant species Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc and comparison with Eriophorum angustifolium and Festuca rubra Merlin

International Nuclear Information System (INIS)

Matthews, David J.; Moran, Bridget M.; Otte, Marinus L.

2005-01-01

Several wetland plant species appear to have constitutive metal tolerance. In previous studies, populations from contaminated and non-contaminated sites of the wetland plants Typha latifolia, Phragmites australis, Glyceria fluitans and Eriophorum angustifolium were found to be tolerant to high concentrations of metals. This study screened three other species of wetland plants: Alisma plantago-aquatica, Carex rostrata and Phalaris arundinacea for innate tolerance to zinc. The degree of tolerance was compared to known zinc-tolerant E. angustifolium and Festuca rubra Merlin. It was found that A. plantago-aquatica and P. arundinacea did not posses innate tolerance to zinc, but that C. rostrata was able to tolerate elevated levels of zinc, at levels comparable to those tolerated by E. angustifolium and F. rubra Merlin. The findings support the theory that some wetland angiosperm species tend to be tolerant to exposure to high levels of metals, regardless of their origin. - Some wetland angiosperms are tolerant to high concentrations of metals, regardless of conditions in the plants' natural habitat

Anti-Inflammatory Effect of By-Products from Haliotis discus hannai in RAW 264.7 Cells

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Ho-Seok Rho

2015-01-01

Full Text Available Several reports promoted the potential of shellfish due to their ability to act as antioxidant, anti-inflammatory, and antimicrobial agents. Pacific abalone, Haliotis discus hannai viscera is, reported to possess bioactivities such as antioxidative stress and anti-inflammatory. In this study, anti-inflammatory potential of mucus-secreting glands from shell-shucking waste of H. discus hannai was evaluated using RAW 264.7 mouse macrophage cell model. Results indicated that presence of H. discus hannai mucosubstance by-products (AM significantly lowered the nitric oxide (NO production along the expressional suppression of inflammatory mediators such as cytokines TNF-α, IL-1β, and IL-6 and enzymes iNOS and COX-2. Also, AM was shown to increase expression of anti-inflammatory response mediator HO-1. Presence of AM also scavenged the free radicals in vitro. In conclusion, by-products of H. discus hannai are suggested to possess notable anti-inflammatory potential which promotes the possibility of utilization as functional food ingredient.

Comparison of three inert markers in measuring apparent nutrient digestibility of juvenile abalone under different culture condition and temperature regimes

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Nur, K. U.; Adams, L.; Stone, D.; Savva, N.; Adams, M.

2018-03-01

A comparative research using three inert markers, chromic oxide, yttrium and ytterbium to measure the apparent nutrient digestibility of experimental feed in juvenile Hybrid abalone (Haliotis rubra X H. laevigata) and Greenlip abalone (H.laevigata) revealed that apparent digestibility of crude protein (ADCP) measured using yttrium and ytterbium in hybrid abalone were significantly different across the treatments. Protein digestibility measured in experimental tanks was higher than those measured in indoor and outdoor commercial tanks, regardless of inert marker used. Chromic oxide led to overestimated ADCP compared to when measured using yttrium and ytterbium. There were no significant interactions between temperature and inert markers when measuring ADCP and apparent digestibility of gross energy (ADGE). However, there was a significant difference of ADCP amongst inert markers when measured in greenlip abalone cultured at two temperatures. While measurements of ADge calculated using three inert markers shared the same value.

Immunostimulation in the urinary bladder by local application of Nocardia rubra cell wall skeleton preparation (Rubratin) for superficial bladder cancer immunotherapy--a phase I/II study

NARCIS (Netherlands)

de Reijke, T. M.; de Boer, E. C.; Schamhart, D. H.; Kurth, K. H.

1997-01-01

Twelve patients with superficial papillary transitional cell carcinoma of the bladder (pTa, pT1) were treated with six consecutive weekly intravesical instillations of Rubratin (in a dose of 1.5, 3.0, or 4.5 mg), a cell wall skeleton preparation of Nocardia rubra (NCW). The main objective of this

KERAGAAN PERTUMBUHAN DAN VARIASI GENETIK ABALON Haliotis squamata Reeve (1846 HASIL SELEKSI F-1

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Gusti Ngurah Permana

2015-12-01

Full Text Available Produksi benih abalon Haliotis squamata skala massal di hatcheri telah berhasil dilakukan di Balai Besar Penelitian dan Pengembangan Budidaya Laut Gondol, Bali. Permasalahan utama dalam budidaya abalon adalah pertumbuhan yang lambat. Keadaan tersebut diduga karena pengaruh faktor genetik dan lingkungan. Penelitian ini bertujuan mengetahui keragaan pertumbuhan dan variasi genetik abalon tumbuh cepat hasil seleksi individu. Hasil penelitian ini diketahui bahwa pembentukan populasi F-1 mempunyai pertumbuhan yang lebih baik dengan F-1 kontrol. Peningkatan bobot yang dicapai 22,15 g atau 17,93% lebih baik dibandingkan F-1 kontrol. Keragaman genetik F-1 terseleksi yang ditunjukkan dari nilai heterozigositas adalah (Ho. 0,023 terjadi penurunan 21,7% jika dibandingkan F-0. Hal ini dapat terjadi karena hilangnya beberapa allele dalam proses seleksi. Terdapat hubungan antara jumlah heterozigot pada lokus tertentu dengan pertumbuhan abalon. Hasil ini diharapkan dapat mendukung upaya meningkatkan produksi benih yang mempunyai performa fenotipe dan genotipe unggul sehingga dapat mendukung kegiatan budidaya abalon yang berkelanjutan.

INDUCTION SPAWNING FOR THE TROPICAL ABALONE (Haliotis asinina IN THE LABORATORY

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D.E. Djoko Setyono

2006-06-01

Full Text Available The main purpose of this study was to test and understand the effectivity of previous successful treatment to induce spawning in temperate abalone, including the use of hydrogen peroxide, vigorous aeration, desiccation, thermal shock, and UV-irradiated seawater, to induce spawning in the tropical abalone (Haliotis asinina from southern Lombok waters, NTB. Approximately 90% of mature animals conditioned in the laboratory could be spawned successfully. Wild freshly mature broodstock collected in the morning during spring low tide failed to spawn under any treatment tried, while in wild freshly mature broodstock collected in the afternoon during spring low tide, approximately 45% of the males and 37% of the females, spawned successfully under all treatments. Mature animals ready to spawn were usually found creeping up the tanks close to the water surface, and were very active but relaxed, and the foot was soft and flabby. In the laboratory, H. asinina from southern Lombok waters released gametes at night between 11:00 pm and 01:00 am. The conditioned broodstock had average batch fecundity ranged from 50,000 to 435,000 eggs and the freshly caught wild broodstock ranged from 50,000 to 105,000 eggs. Approximately 75% of spawned eggs were found to be ripe and the remaining 25% were unripe. In general, no artificial spawning induction is required to spawn tropical abalone (H. asinina in laboratory (hatchery.

Involvement of Antizyme Characterized from the Small Abalone Haliotis diversicolor in Gonadal Development.

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Wei-Dong Li

Full Text Available The small abalone Haliotis diversicolor is an economically important mollusk that is widely cultivated in Southern China. Gonad precocity may affect the aquaculture of small abalone. Polyamines, which are small cationic molecules essential for cellular proliferation, may affect gonadal development. Ornithine decarboxylase (ODC and antizyme (AZ are essential elements of a feedback circuit that regulates cellular polyamines. This paper presents the molecular cloning and characterization of AZ from small abalone. Sequence analysis showed that the cDNA sequence of H. diversicolor AZ (HdiODCAZ consisted of two overlapping open reading frames (ORFs and conformed to the +1 frameshift property of the frame. Thin Layer chromatography (TLC analysis suggested that the expressed protein encoded by +1 ORF2 was the functional AZ that targets ODC to 26S proteasome degradation. The result demonstrated that the expression level of AZ was higher than that of ODC in the ovary of small abalone. In addition, the expression profiles of ODC and AZ at the different development stages of the ovary indicated that these two genes might be involved in the gonadal development of small abalone.

Effects of dietary menadione on the activity of antioxidant enzymes in abalone, Haliotis discus hannai Ino

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Fu, Jinghua; Xu, Wei; Mai, Kangsen; Zhang, Wenbing; Feng, Xiuni; Liufu, Zhiguo

2012-01-01

A 240-day growth experiment in a re-circulating water system was conducted to investigate the effects of dietary menadione on the growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of juvenile abalone (initial weight: 1.19 ± 0.01 g; shell length: 19.23 ± 0.01 mm) were fed to satiation with 3 semi-purified diets containing 0, 10, and 1 000 mg menadione sodium bisulfite (MSB)/kg, respectively. Results show that there were no significant differences in the rate of weight gain or in the daily increment in shell length of abalone among different treatments. Activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST) and glutathione reductase (GR) in viscera were significantly decreased with dietary menadione. However, activities of these enzymes except for GPX in muscle were increased. Therefore, antioxidant responses of abalone were increased in muscle and decreased in viscera by dietary menadione.

Acute toxicity of live and decomposing green alga Ulva ( Enteromorpha) prolifera to abalone Haliotis discus hannai

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Wang, Chao; Yu, Rencheng; Zhou, Mingjiang

2011-05-01

From 2007 to 2009, large-scale blooms of green algae (the so-called "green tides") occurred every summer in the Yellow Sea, China. In June 2008, huge amounts of floating green algae accumulated along the coast of Qingdao and led to mass mortality of cultured abalone and sea cucumber. However, the mechanism for the mass mortality of cultured animals remains undetermined. This study examined the toxic effects of Ulva ( Enteromorpha) prolifera, the causative species of green tides in the Yellow Sea during the last three years. The acute toxicity of fresh culture medium and decomposing algal effluent of U. prolifera to the cultured abalone Haliotis discus hannai were tested. It was found that both fresh culture medium and decomposing algal effluent had toxic effects to abalone, and decomposing algal effluent was more toxic than fresh culture medium. The acute toxicity of decomposing algal effluent could be attributed to the ammonia and sulfide presented in the effluent, as well as the hypoxia caused by the decomposition process.

Immunostimulation in the urinary bladder by local application of Nocardia rubra cell-wall skeletons (Rubratin) and bacillus Calmette-Guérin as therapy for superficial bladder cancer: a comparative study

NARCIS (Netherlands)

de Boer, E. C.; de Reijke, T. M.; Vos, P. C.; Kurth, K. H.; Schamhart, D. H.

2000-01-01

Twelve patients with superficial bladder cancer were treated with intravesical instillations of Rubratin (ASTA Pharma AG, Frankfurt, Germany), a cell-wall preparation of Nocardia rubra. The objective was to compare the immunostimulating effect of Rubratin with that of bacillus Calmette-Guérin (BCG).

Highly Enantioselective Production of (R-Halohydrins with Whole Cells of Rhodotorula rubra KCh 82 Culture

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Tomasz Janeczko

2014-12-01

Full Text Available Biotransformation of ten α-haloacetophenones in the growing culture of the strain Rhodotorula rubra KCh 82 has been carried out. Nine of the substrates underwent an effective enantioselective reduction to the respective (R-alcohols according to Prelog’s rule, with the exception of 2-chloro-1,2-diphenylethan-1-one that was not transformed by this strain. The expected reduction proceeded without dehalogenation, leading to the respective (R-halohydrins in high yields. The use of this biocatalyst yielded (R-2-bromo-1-phenyl-ethan-1-ol (enantiomeric excess (ee = 97% and its derivatives: 4'-Bromo- (ee = 99%; 4'-Chloro- (ee > 99%; 4'-Methoxy- (ee = 96%; 3'-Methoxy- (ee = 93%; 2'-Methoxy- (ee = 98%. There were also obtained and characterized 2,4'-dichloro-, 2,2',4'-trichloro- and 2-chloro-4'-fluoro-phenyetan-1-ol with >99% of enantiomeric excesses.

Highly enantioselective production of (R)-halohydrins with whole cells of Rhodotorula rubra KCh 82 culture.

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Janeczko, Tomasz; Dymarska, Monika; Kostrzewa-Susłow, Edyta

2014-12-04

Biotransformation of ten α-haloacetophenones in the growing culture of the strain Rhodotorula rubra KCh 82 has been carried out. Nine of the substrates underwent an effective enantioselective reduction to the respective (R)-alcohols according to Prelog's rule, with the exception of 2-chloro-1,2-diphenylethan-1-one that was not transformed by this strain. The expected reduction proceeded without dehalogenation, leading to the respective (R)-halohydrins in high yields. The use of this biocatalyst yielded (R)-2-bromo-1-phenyl-ethan-1-ol (enantiomeric excess (ee) = 97%) and its derivatives: 4'-Bromo- (ee = 99%); 4'-Chloro- (ee > 99%); 4'-Methoxy- (ee = 96%); 3'-Methoxy- (ee = 93%); 2'-Methoxy- (ee = 98%). There were also obtained and characterized 2,4'-dichloro-, 2,2',4'-trichloro- and 2-chloro-4'-fluoro-phenyetan-1-ol with >99% of enantiomeric excesses.

Ustekinumab as an Alternative Treatment Option for Chronic Pityriasis Rubra Pilaris

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Mudit Chowdhary

2015-03-01

Full Text Available Pityriasis rubra pilaris (PRP is an exceptionally rare, chronic inflammatory dermatosis of unknown etiology. Patients classically present with small, follicular keratosis and salmon-colored plaques that begin at the head and neck and slowly progress to widespread erythroderma including the palms and soles. It is difficult to distinguish PRP from other inflammatory dermatoses; however, features that help aid in the diagnosis include ‘islands' of spared skin, orangish hue and typical findings on biopsy. There are no specific guidelines on therapy and treatment options include corticosteroids, vitamin D analogs, retinoids, methotrexate, cyclosporine, azathioprine and tumor necrosis factor alpha antagonists. Unfortunately options are limited for patients when these drugs do not work. We report a case of chronic PRP, refractory to conventional treatment, successfully treated with ustekinumab monotherapy. The patient was treated with 90 mg subcutaneous ustekinumab injections and began to show improvement within only 8 weeks. Long-term control of the disease has been attained without any significant side effects. We report this case to show that ustekinumab can be used as an alternative treatment method for patients with chronic, unremitting PRP. Treatment response is remarkably rapid and the infrequent dosing leads to patient compliance and a significantly improved quality of life.

Isospora cardellinae n. sp. (Apicomplexa: Eimeriidae) from the red warbler Cardellina rubra (Swainson) (Passeriformes: Parulidae) in Mexico.

Science.gov (United States)

Salgado-Miranda, Celene; Medina, Juan Pablo; Zepeda-Velázquez, Andrea Paloma; García-Conejo, Michele; Galindo-Sánchez, Karla Patricia; Janczur, Mariusz Krzysztof; Soriano-Vargas, Edgardo

2016-10-01

A new coccidian species (Protozoa: Apicomplexa: Eimeriidae) collected from the red warbler Cardellina rubra (Swainson) is reported from the Nevado de Toluca National Park, Mexico. Isospora cardellinae n. sp. has subspherical oöcysts, measuring on average 26.6 × 25.4 μm, with smooth, bi-layered wall, c.1.3 μm thick. Micropyle, oöcyst residuum, and polar granule are absent. Sporocysts are ovoidal, measuring on average 19.0 × 12.0 µm, with a knob-like Stieda body, a trapezoidal sub-Stieda body and sporocyst residuum composed of scattered spherules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the fourth description of an isosporoid coccidian infecting a New World warbler.

Diatom diet selectivity by early post-larval abalone Haliotis diversicolor supertexta under hatchery conditions

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Zhang, Yuyu; Gao, Yahui; Liang, Junrong; Chen, Changping; Zhao, Donghai; Li, Xuesong; Li, Yang; Wu, Wenzhong

2010-11-01

Benthic diatoms constitute the primary diet of abalone during their early stages of development. To evaluate the dietary preferences of early post-larval abalone, Haliotis diversicolor supertexta, we analyzed the gut contents of post-larvae that settled on diatom films. We compared the abundance and species diversity of diatom assemblages in the gut to those of the epiphytic diatom assemblages on the attachment films, and identified 40 benthic diatom species in the gut contents of post-larvae 12 to 24 d after settlement. The most abundant taxa in the gut contents were Navicula spp., Amphora copulate, and Amphora coffeaeformis. Navicula spp. accounted for 64.0% of the cell density. In the attachment films, we identified 110 diatom species belonging to 38 genera. Pennate diatoms were the dominant members including the species Amphiprora alata, Cocconeis placentula var. euglypta, Cylindrotheca closterium, Navicula sp. 2, and A. coffeaeformis. Nano-diatoms (abalone seed. The difference of the composition and abundance of diatoms between in the guts and on the biofilms suggests that early post-larval grazing was selective. An early post-larval abalone preferred nano-diatoms and the genera Navicula and Amphora during the month after settlement.

Anticoagulant Activity and Structural Characterization of Polysaccharide from Abalone (Haliotis discus hannai Ino Gonad

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Jun Zhao

2016-06-01

Full Text Available In this study, we aimed at characterizing the structure and the anticoagulant activity of a polysaccharide fraction (AGP33 isolated from the gonads of Haliotis discus hannai Ino. AGP33 was extracted by enzymatic hydrolysis and purified by ion-exchange and gel-filtration chromatography. The backbone fraction of AGP33 (BAGP33, which appeared to contain of mannose, glucose and galactose, was prepared by partial acid hydrolysis. According to methylation and nuclear magnetic resonance (NMR spectroscopy, the backbone of AGP33 was identified as mainly consisting of 1→3-linked, 1→4-linked, and 1→6-linked monosaccharides. AGP33 is a sulfated polysaccharide with sulfates occur at 3-O- and 4-O-positions. It prolonged thromboplastin time (APTT, thrombin time (TT and prothrombin time (PT compared to a saline control solution in a dosage-dependent manner. AGP33 exhibited an extension (p < 0.01 of APTT compared to the saline group at concentrations higher than 5 μg/mL. AGP33 exhibited higher anticoagulant activity than its desulfated product (AGP33-des and BAGP33. The results showed that polysaccharide with higher molecular weight and sulfate content demonstrated greater anticoagulant activity.

Presence of understory shrubs constrains carbon gain in sunflecks by advance-regeneration seedlings: evidence from Quercus Rubra seedling grouwing in understory forest patches with or without evergreen shrubs present

Science.gov (United States)

E.T. Nilsen; T.T. Lei; S.W. Semones

2009-01-01

We investigated whether dynamic photosynthesis of understory Quercus rubra L. (Fagaceae) seedlings can acclimate to the altered pattern of sunflecks in forest patches with Rhododendron maximum L. (Ericaceae), an understory evergreen shrub. Maximum photosynthesis (A) and total CO2 accumulated during lightflecks was greatest for 400-s lightflecks, intermediate for 150-s...

Pyrosequencing of Haliotis diversicolor transcriptomes: insights into early developmental molluscan gene expression.

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Zi-Xia Huang

Full Text Available BACKGROUND: The abalone Haliotis diversicolor is a good model for study of the settlement and metamorphosis, which are widespread marine ecological phenomena. However, information on the global gene backgrounds and gene expression profiles for the early development of abalones is lacking. METHODOLOGY/PRINCIPAL FINDINGS: In this study, eight non-normalized and multiplex barcode-labeled transcriptomes were sequenced using a 454 GS system to cover the early developmental stages of the abalone H. diversicolor. The assembly generated 35,415 unigenes, of which 7,566 were assigned GO terms. A global gene expression profile containing 636 scaffolds/contigs was constructed and was proven reliable using qPCR evaluation. It indicated that there may be existing dramatic phase transitions. Bioprocesses were proposed, including the 'lock system' in mature eggs, the collagen shells of the trochophore larvae and the development of chambered extracellular matrix (ECM structures within the earliest postlarvae. CONCLUSION: This study globally details the first 454 sequencing data for larval stages of H. diversicolor. A basic analysis of the larval transcriptomes and cluster of the gene expression profile indicates that each stage possesses a batch of specific genes that are indispensable during embryonic development, especially during the two-cell, trochophore and early postlarval stages. These data will provide a fundamental resource for future physiological works on abalones, revealing the mechanisms of settlement and metamorphosis at the molecular level.

Proteomic analysis of the organic matrix of the abalone Haliotis asinina calcified shell

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Degnan Bernard M

2010-11-01

Full Text Available Abstract Background The formation of the molluscan shell is regulated to a large extent by a matrix of extracellular macromolecules that are secreted by the shell forming tissue, the mantle. This so called "calcifying matrix" is a complex mixture of proteins and glycoproteins that is assembled and occluded within the mineral phase during the calcification process. While the importance of the calcifying matrix to shell formation has long been appreciated, most of its protein components remain uncharacterised. Results Recent expressed sequence tag (EST investigations of the mantle tissue from the tropical abalone (Haliotis asinina provide an opportunity to further characterise the proteins in the shell by a proteomic approach. In this study, we have identified a total of 14 proteins from distinct calcified layers of the shell. Only two of these proteins have been previously characterised from abalone shells. Among the novel proteins are several glutamine- and methionine-rich motifs and hydrophobic glycine-, alanine- and acidic aspartate-rich domains. In addition, two of the new proteins contained Kunitz-like and WAP (whey acidic protein protease inhibitor domains. Conclusion This is one of the first comprehensive proteomic study of a molluscan shell, and should provide a platform for further characterization of matrix protein functions and interactions.

BRICHOS domain-containing leukocyte cell-derived chemotaxin 1-like cDNA from disk abalone Haliotis discus discus.

Science.gov (United States)

Kim, Yucheol; De Zoysa, Mahanama; Lee, Youngdeuk; Whang, Ilson; Lee, Jehee

2010-11-01

A BRICHOS domain-containing leukocyte cell-derived chemotaxin 1-like cDNA was cloned from the disk abalone (Haliotis discus discus) and designated as AbLECT-1. A full-length (705 bp) of AbLECT-1 cDNA was composed of a 576 bp open reading frame that translates into a putative peptide of 192 amino acids. Deduced amino acid sequence of AbLECT-1 had 15.5- and 27.8% identity and similarity to human LECT-1, respectively. Quantitative real-time PCR analysis results showed that the mRNA of AbLECT-1 was constitutively expressed in abalone hemocytes, gills, mantle, muscle, digestive tract and hepatopancreas in a tissue-specific manner. Moreover, the AbLECT-1 transcription level was induced in hemocytes after challenge with Vibrio alginolyticus, Vibrio parahemolyticus, and Listeria monocytogenes suggesting that it may be involved in immune response reactions in abalone. Copyright 2010 Elsevier Ltd. All rights reserved.

Growth of the European abalone ( Haliotis tuberculata L.) in situ: Seasonality and ageing using stable oxygen isotopes

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Roussel, Sabine; Huchette, Sylvain; Clavier, Jacques; Chauvaud, Laurent

2011-02-01

The ormer, Haliotis tuberculata is the only European abalone species commercially exploited. The determination of growth and age in the wild is an important tool for fisheries and aquaculture management. However, the ageing technique used in the past in the field is unreliable. The stable oxygen isotope composition ( 18O/ 16O) of the shell depends on the temperature and oxygen isotope composition of the ambient sea water. The stable oxygen isotope technique, developed to study paleoclimatological changes in shellfish, was applied to three H. tuberculata specimens collected in north-west Brittany. For the specimens collected, the oxygen isotope ratios of the shell reflected the seasonal cycle in the temperature. From winter-to-winter cycles, estimates of the age and the annual growth increment, ranging from 13 to 55 mm per year were obtained. This study shows that stable oxygen isotopes can be a reliable tool for ageing and growth studies of this abalone species in the wild, and for validating other estimates.

Effects of invasive European fire ants (Myrmica rubra on herring gull (Larus argentatus reproduction.

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Luke E DeFisher

Full Text Available Various invasive ant species have negatively affected reproductive success in birds by disrupting nest site selection, incubation patterns, food supply, and by direct predation on nestlings. Impacts can be particularly severe when non-native ants colonize seabird nesting islands where thousands of birds may nest in high densities on the ground or in burrows or crevices. Here we report on the first documented effects of Myrmica rubra, the European fire ant, on the reproduction of birds in its non-native range. We documented herring gulls (Larus argentatus on Appledore Island, Maine, engaging in more erratic incubation behaviors at nests infested by the ants. Newly-hatched chicks in some nests were swarmed by ants, leading to rapid chick death. Due to high overall rates of chick mortality, survival probabilities did not vary between nests with and without ant activity, however chick growth rates were slower at nests with ants than at ant-free nests. Ant infestation likely leads to longer-term fitness consequences because slower growth rates early in life may ultimately lead to lower post-fledging survival probabilities.

Probabilistic risk assessment of abalone Haliotis diversicolor supertexta exposed to waterborne zinc

International Nuclear Information System (INIS)

Liao Chungmin; Ling Minpei

2004-01-01

This paper describes a risk assessment approach that integrates predicted tissue concentrations of zinc (Zn) with a concentration-response relationship and leads to predictions of survival risk for pond abalone Haliotis diversicolor supertexta as well as to the uncertainties associated with these predictions. The models implemented include a probabilistic bioaccumulation model, which linking biokinetic and consumer-resource models, accounts for Zn exposure profile and a modified Hill model for reconstructing a dose-response profile for abalone exposed to waterborne Zn. The growth risk is assessed by hazard quotients characterized by measured water level and chronic no-observed effect concentration. Our risk analyses for H. diversicolor supertexta reared near Toucheng, Kouhu, and Anping, respectively, in north, central, and south Taiwan region indicate a relatively low likelihood that survival is being affected by waterborne Zn. Expected risks of mortality for abalone were estimated as 0.46 (Toucheng), 0.36 (Kouhu), and 0.29 (Anping). The predicted 90th-percentiles of hazard quotient for potential growth risk were estimated as 1.94 (Toucheng), 0.47 (Kouhu), and 0.51 (Anping). These findings indicate that waterborne Zn exposure poses no significant risk to pond abalone in Kouhu and Anping, yet a relative high growth risk in Toucheng is alarming. Because of a scarcity of toxicity and exposure data, the probabilistic risk assessment was based on very conservative assumptions. - A novel risk assessment method was developed for abalone

Probabilistic risk assessment of abalone Haliotis diversicolor supertexta exposed to waterborne zinc

Energy Technology Data Exchange (ETDEWEB)

Liao Chungmin; Ling Minpei

2004-01-01

This paper describes a risk assessment approach that integrates predicted tissue concentrations of zinc (Zn) with a concentration-response relationship and leads to predictions of survival risk for pond abalone Haliotis diversicolor supertexta as well as to the uncertainties associated with these predictions. The models implemented include a probabilistic bioaccumulation model, which linking biokinetic and consumer-resource models, accounts for Zn exposure profile and a modified Hill model for reconstructing a dose-response profile for abalone exposed to waterborne Zn. The growth risk is assessed by hazard quotients characterized by measured water level and chronic no-observed effect concentration. Our risk analyses for H. diversicolor supertexta reared near Toucheng, Kouhu, and Anping, respectively, in north, central, and south Taiwan region indicate a relatively low likelihood that survival is being affected by waterborne Zn. Expected risks of mortality for abalone were estimated as 0.46 (Toucheng), 0.36 (Kouhu), and 0.29 (Anping). The predicted 90th-percentiles of hazard quotient for potential growth risk were estimated as 1.94 (Toucheng), 0.47 (Kouhu), and 0.51 (Anping). These findings indicate that waterborne Zn exposure poses no significant risk to pond abalone in Kouhu and Anping, yet a relative high growth risk in Toucheng is alarming. Because of a scarcity of toxicity and exposure data, the probabilistic risk assessment was based on very conservative assumptions. - A novel risk assessment method was developed for abalone.

Anti-Coagulant and Anti-Thrombotic Properties of Blacklip Abalone (Haliotis rubra): In Vitro and Animal Studies.

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Suleria, Hafiz Ansar Rasul; Masci, Paul P; Zhao, Kong-Nan; Addepalli, Rama; Chen, Wei; Osborne, Simone A; Gobe, Glenda C

2017-08-04

Sulphated polysaccharides with anti-thrombotic and anti-coagulant activities have been found in various marine biota. In this study, a previously characterised anti-thrombotic and anti-coagulant extract from blacklip abalone was fractionated by anion exchange chromatography (AEC), pooled (on a sulphated polysaccharide basis) and administered to Wistar rats via oral gavage (N = 8) for assessment as an oral therapeutic. To ensure that the preparation had anti-coagulant activity prior to oral administration, it was assessed in rat blood by thromboelastography (TEG) significantly increasing reaction (R) time (or time until clot formation). Following in vitro confirmation of anti-coagulant activity, 40 mg of the preparation was orally administered to rats with blood samples collected at 2, 4, and 6 h post-gavage. Assessment of all blood samples by TEG showed some prolongation of R time from 355 to 380 s after 4 h. Dosing of the post-gavage blood samples with the abalone preparation to confirm anti-thrombotic activity in vitro revealed residual anti-coagulant activity, further suggesting that oral administration did increase anti-coagulant potential in the collected blood but that bioavailability was low. Assessment of tissues and haematological parameters showed no obvious harmful effects of the abalone preparation in animals. In summary, even though oral administration of fractionated and pooled blacklip abalone extract to rats delayed clotting after 4 h, bioavailability of the preparation appeared to be low and may be more appropriate for intravenous administration as an anti-thrombotic or anti-coagulant therapeutic.

Genetic differentiation between fake abalone and genuine Haliotis species using the forensically informative nucleotide sequencing (FINS) method.

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Ha, Wai Y; Reid, David G; Kam, Wan L; Lau, Yuk Y; Sham, Wing C; Tam, Silvia Y K; Sin, Della W M; Mok, Chuen S

2011-05-25

Abalones ( Haliotis species) are a popular delicacy and commonly preserved in dried form either whole or in slices or small pieces for consumption in Asian countries. Driven by the huge profit from trading abalones, dishonest traders may substitute other molluscan species for processed abalone, of which the morphological characteristics are frequently lost in the processed form. For protection of consumer rights and law enforcement against fraud, there is a need for an effective methodology to differentiate between fake and genuine abalone. This paper describes a method (validated according to the international forensic guidelines provided by SWGDAM) for the identification of fake abalone species using forensically informative nucleotide sequence (FINS) analysis. A study of the local market revealed that many claimed "abalone slice" samples on sale are not genuine. The fake abalone samples were found to be either volutids of the genus Cymbium (93%) or the muricid Concholepas concholepas (7%). This is the first report of Cymbium species being used for the preparation and sale as "abalone" in dried sliced form in Hong Kong.

Isolation and identification of lactic acid bacteria from abalone (Haliotis asinina as a potential candidate of probiotic

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YAYAN SOFYAN

2010-01-01

Full Text Available Sarkono, Faturrahman, Sofyan Y. 2010. Isolation and identification of lactic acid bacteria from abalone (Haliotis asinina as a potential candidate of probiotic. Nusantara Bioscience 2: 38-42. The purpose of this study was to isolate, select and characterize lactic acid bacteria (LAB from abalone as a potential candidate probiotic in abalone cultivation system. Selective isolation of LAB performed using de Man Rogosa Sharpe medium. LAB isolate that potential as probiotics was screened. Selection was based on its ability to suppress the growth of pathogenic bacteria, bacterial resistance to acidic conditions and bacterial resistance to bile salts (bile. Further characterization and identification conducted to determine the species. The results showed that two of the ten isolates potential to be developed as probiotic bacteria that have the ability to inhibit several pathogenic bacteria such as Eschericia coli, Bacillus cereus dan Staphylococus aureus, able to grow at acidic condition and bile tolerance during the incubation for 24 hour. Based on the API test kit, the both of isolate identified as members of the species Lactobacillus paracasei ssp. paracasei.

Preparation, characterisation and use for antioxidant oligosaccharides of a cellulase from abalone (Haliotis discus hannai) viscera.

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Tao, Zhi-Peng; Sun, Le-Chang; Qiu, Xu-Jian; Cai, Qiu-Feng; Liu, Guang-Ming; Su, Wen-Jin; Cao, Min-Jie

2016-07-01

In China, abalone (Haliotis discus hannai) production is growing annually. During industrial processing, the viscera, which are abundant of cellulase, are usually discarded or processed into low-value feedstuff. Thus, it is of interest to obtain cellulase from abalone viscera and investigate its application for preparation of functional oligosaccharides. A cellulase was purified from the hepatopancreas of abalone by ammonium sulfate precipitation and two-steps column chromatography. The molecular weight of the cellulase was 45 kDa on SDS-PAGE. Peptide mass fingerprinting analysis yielded 103 amino acid residues, which were identical to cellulases from other species of abalone. Substrate specificity analysis indicated that the cellulase is an endo-1,4-β-glucanase. Hydrolysis of seaweed Porphyra haitanensis polysaccharides by the enzyme produced oligosaccharides with degree of polymerisation of two to four, whose monosaccharide composition was 58% galactose, 4% glucose and 38% xylose. The oligosaccharides revealed 2,2'-diphenyl-1-picrylhydrazyl free radical as well as hydrogen peroxide scavenging activity. It is feasible and meaningful to utilise cellulase from the viscera of abalone for preparation of functional oligosaccharides. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Abalone, Haliotis mariae (Wood, 1828, Hatchery and Seed Production Trials in Oman

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Khalfan M. Al-Rashdi

2008-01-01

Full Text Available Hatchery and seed production trials for the Omani endemic abalone Haliotis mariae were carried out at the land-based Mirbat Abalone Seed Production Station in Oman between 1999 and 2000. The methods developed for broodstock conditioning, induction of spawning and fertilization, larval settlement, and the handling of small juveniles are shown. Abalone collected in the post-monsoon period and held for 2 months matured faster than those collected before the monsoon and held for 6 months. Spawning induction of males and females had 63% and 11% success rates respectively, and the morphology of early larval stages is shown. Survival rates of veliger larvae introduced to settlement plates ranged from 35.9% to 73.7%, but the survival of post-larvae was low at 0.1% to 3.6%. The high mortality rate was attributed to invasions of filamentous green- and coralline algae on settlement plates and occurrence of low quantity of diatoms as food. Juveniles reacted best to 2% ethanol as anaesthetic, dropping off culture plates within 4 min and recovering within 17 min. Cultured abalone reached an average shell length of 52.9 mm over 13 months, which translates to an increment of 4.1 mm.mon-1. The overall conclusion of these preliminary research trials confirms  that H. mariae can be cultured successfully in Oman. Further studies on the standardization of the techniques would help in stock enhancement programmes and commercial farming.

The cross-tissue metabolic response of abalone (Haliotis midae) to functional hypoxia.

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Venter, Leonie; Loots, Du Toit; Mienie, Lodewyk J; Jansen van Rensburg, Peet J; Mason, Shayne; Vosloo, Andre; Lindeque, Jeremie Z

2018-03-23

Functional hypoxia is a stress condition caused by the abalone itself as a result of increased muscle activity, which generally necessitates the employment of anaerobic metabolism if the activity is sustained for prolonged periods. With that being said, abalone are highly reliant on anaerobic metabolism to provide partial compensation for energy production during oxygen-deprived episodes. However, current knowledge on the holistic metabolic response for energy metabolism during functional hypoxia, and the contribution of different metabolic pathways and various abalone tissues towards the overall accumulation of anaerobic end-products in abalone are scarce. Metabolomics analysis of adductor muscle, foot muscle, left gill, right gill, haemolymph and epipodial tissue samples indicated that South African abalone ( Haliotis midae) subjected to functional hypoxia utilises predominantly anaerobic metabolism, and depends on all of the main metabolite classes (proteins, carbohydrates and lipids) for energy supply. Functional hypoxia caused increased levels of anaerobic end-products: lactate, alanopine, tauropine, succinate and alanine. Also, elevation in arginine levels was detected, confirming that abalone use phosphoarginine to generate energy during functional hypoxia. Different tissues showed varied metabolic responses to hypoxia, with functional hypoxia showing excessive changes in the adductor muscle and gills. From this metabolomics investigation, it becomes evident that abalone are metabolically able to produce sufficient amounts of energy when functional hypoxia is experienced. Also, tissue interplay enables the adjustment of H. midae energy requirements as their metabolism shifts from aerobic to anaerobic respiration during functional hypoxia.This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

The cross-tissue metabolic response of abalone (Haliotis midae to functional hypoxia

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Leonie Venter

2018-03-01

Full Text Available Functional hypoxia is a stress condition caused by the abalone itself as a result of increased muscle activity, which generally necessitates the employment of anaerobic metabolism if the activity is sustained for prolonged periods. With that being said, abalone are highly reliant on anaerobic metabolism to provide partial compensation for energy production during oxygen-deprived episodes. However, current knowledge on the holistic metabolic response for energy metabolism during functional hypoxia, and the contribution of different metabolic pathways and various abalone tissues towards the overall accumulation of anaerobic end-products in abalone are scarce. Metabolomics analysis of adductor muscle, foot muscle, left gill, right gill, haemolymph and epipodial tissue samples indicated that South African abalone (Haliotis midae subjected to functional hypoxia utilises predominantly anaerobic metabolism, and depends on all of the main metabolite classes (proteins, carbohydrates and lipids for energy supply. Functional hypoxia caused increased levels of anaerobic end-products: lactate, alanopine, tauropine, succinate and alanine. Also, elevation in arginine levels was detected, confirming that abalone use phosphoarginine to generate energy during functional hypoxia. Different tissues showed varied metabolic responses to hypoxia, with functional hypoxia showing excessive changes in the adductor muscle and gills. From this metabolomics investigation, it becomes evident that abalone are metabolically able to produce sufficient amounts of energy when functional hypoxia is experienced. Also, tissue interplay enables the adjustment of H. midae energy requirements as their metabolism shifts from aerobic to anaerobic respiration during functional hypoxia. This article has an associated First Person interview with the first author of the paper.

Back to America: tracking the origin of European introduced populations of Quercus rubra L.

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Merceron, Nastasia R; Leroy, Thibault; Chancerel, Emilie; Romero-Severson, Jeanne; Borkowski, Daniel S; Ducousso, Alexis; Monty, Arnaud; Porté, Annabel J; Kremer, Antoine

2017-09-01

Quercus rubra has been introduced in Europe since the end of the 17th century. It is widely distributed today across this continent and considered invasive in some countries. Here, we investigated the distribution of genetic diversity of both native and introduced populations with the aim of tracing the origin of introduced populations. A large sampling of 883 individuals from 73 native and 38 European locations were genotyped at 69 SNPs. In the natural range, we found a continuous geographic gradient of variation with a predominant latitudinal component. We explored the existence of ancestral populations by performing Bayesian clustering analysis and found support for two or three ancestral genetic clusters. Approximate Bayesian Computations analyses based on these two or three clusters support recent extensive secondary contacts between them, suggesting that present-day continuous genetic variation resulted from recent admixture. In the introduced range, one main genetic cluster was not recovered in Europe, suggesting that source populations were preferentially located in the northern part of the natural distribution. However, our results cannot refute the introduction of populations from the southern states that did not survive in Europe.

Effects of dietary carbohydrates sources on lipids compositions in abalone, Haliotis discus hannai Ino

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Wang, Weifang; Mai, Kangsen; Zhang, Wenbing; Xu, Wei; Ai, Qinghui; Yao, Chunfeng; Li, Huitao

2009-09-01

A study was conducted to evaluate the effects of dietary carbohydrates on triglyceride, cholesterol and fatty acid concentrations in abalone, Haliotis discus hannai Ino. Six semi-purified diets with different carbohydrates (dextrin, heat-treated wheat starch, wheat starch, corn starch, tapioca starch and potato starch, respectively), all containing a carbohydrate level of 33.5%, were fed to abalone (initial shell length: 29.98 mm ± 0.09 mm; initial weight: 3.42 g ± 0.02 g) for 24 weeks in a recirculation system. The results indicate that serum triglyceride concentrations were significantly ( P abalone fed with dextrin, heat-treated wheat starch and wheat starch than those fed with corn starch, and serum cholesterol concentrations were significantly ( P abalone fed with dextrin, heat-treated wheat starch than those fed with corn starch. Fatty acid C20:4n-6 in the foot muscles were significantly ( P abalone fed with dextrin than those fed with wheat starch, corn starch, tapioca starch and potato starch. Fatty acid C20:4n-6 in hepatopancreas was significantly ( P abalone fed with heat-treated wheat starch than those fed with corn starch, tapioca starch and potato starch. Fatty acid C22:6n-3 in the foot muscles were significantly ( P abalone fed with dextrin and heat-treated wheat starch than those fed with wheat starch and potato starch.

Effects of Multiple Stressors on Red Abalone (Haliotis rufescens) Fertilization Success

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Boch, C. A.; Aalto, E.; De Leo, G.; Litvin, S.; Lovera, C.; Micheli, F.; Woodson, C. B.; Monismith, S. G.; Barry, J. P.

2016-02-01

Acidification, hypoxia, and ocean warming are escalating threats in the world's coastal waters, with potentially severe consequences for marine life and ocean-based economies. In particular, eastern boundary current ecosystems, including the California Current Large Marine Ecosystem (CCLME), are experiencing large-scale declines in pH and dissolved oxygen (DO)—with the latter linked to changes in thermal stratification and shoaling of the oxygen minimum zone. To examine the consequences of ocean acidification and other climate-related changes in oceanographic conditions on nearshore marine populations within the CCLME, we are assessing the potential effects of current and future upwelling-type conditions on the population dynamics of the red abalone (Haliotis rufescens), with a focus on sensitive early life history phases (e.g., fertilization, larval development, and juvenile growth and survival) expected to be important determinants of population dynamics. Here, we present the first experimental results on the impacts of combined exposures of low pH and low DO on abalone fertilization success. Our results show that abalone fertilization success is significantly reduced when the gametes are exposed to a decrease in seawater pH from 8.0 to 7.2. Furthermore, low pH in combination with hypoxic exposure—e.g., a decrease in dissolved oxygen from 6 mg/L DO to 1 mg/L DO—does not further decrease fertilization rates, suggesting a lack of synergistic or additive effects of these multiple stressors on the reduction of fertilization success. Although the focus of this study is to characterize the effects of multiple stressors on the early life history of abalone, the implications of these results are expected to be relevant for a variety of marine taxa with similar reproductive modes.

Surgical and medical management for fractures of the second through fifth metacarpals in a red ruffed lemur (Varecia rubra).

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Cerveny, Shannon N S; Harper, Justin; Voges, Andra; Coke, Rob L

2013-03-01

A 21-yr-old female red ruffed lemur (Varecia rubra) was presented with swelling and disuse of the right manus. Severely displaced fractures of metacarpals II-V were diagnosed radiographically. The fractures were surgically stabilized with intramedullary Kirschner wires attached externally with an acrylic external fixator and a bone plate on the dorsal aspect of metacarpal III. The fractures of metacarpals II-V were predominantly healed on radiographs obtained 12 wk after surgery. However, diffuse disuse osteopenia and phalangeal contracture were present, with possible osteomyelitis. An exercise regimen of the affected hand was initiated due to the incomplete extension of the phalanges. After 4 wk of therapy, the extension of the phalanges had improved and the fractures appeared radiographically to be nearly completely healed. Although metacarpal fractures are common in nonhuman primates, they are reported infrequently in the literature.

Tributyltin toxicity in abalone (Haliotis diversicolor supertexta) assessed by antioxidant enzyme activity, metabolic response, and histopathology.

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Zhou, Jin; Zhu, Xiao-shan; Cai, Zhong-hua

2010-11-15

A toxicity test was performed to investigate the possible harmful effects of tributyltin (TBT) on abalone (Haliotis diversicolor supertexta). Animals were exposed to TBT in a range of environmentally relevant concentrations (2, 10 and 50 ng/L) for 30 days under laboratory conditions. TBT-free conditions were used as control treatments. The activity of antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD), and malondialdehyde (MDA), along with levels of haemolymph metabolites, and hepatopancreas histopathology were analyzed. The results showed that TBT decreased SOD activity, and increased POD level and MDA production in a dose-dependent way, indicating that oxidative injury was induced by TBT. Haemolymph metabolite measurements showed that TBT increased alanine and glutamate levels, and decreased glucose content, which suggested perturbation of energy metabolism. Elevated levels of acetate and pyruvate in the haemolymph indicated partial alteration of lipid metabolism. A decrease in lactate and an increase in succinate, an intermediate of the tricarboxylic acid (TCA) cycle, indicated disturbance of amino acid metabolism. Hepatopancreas tissues also exhibited inflammatory responses characterized by histopathological changes such as cell swelling, granular degeneration, and inflammation. Taken together, these results demonstrated that TBT was a potential toxin with a variety of deleterious effects on abalone. Copyright © 2010 Elsevier B.V. All rights reserved.

Toxic effects of several phthalate esters on the embryos and larvae of abalone Haliotis diversicolor supertexta

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Yang, Zhihui; Zhang, Xiangjing; Cai, Zhonghua

2009-05-01

As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of H. diversicolor supertexta can be used to indicate toxicity of the PAEs.

Quercus rubra-associated ectomycorrhizal fungal communities of disturbed urban sites and mature forests.

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Karpati, Amy S; Handel, Steven N; Dighton, John; Horton, Thomas R

2011-08-01

The presence and quality of the belowground mycorrhizal fungal community could greatly influence plant community structure and host species response. This study tests whether mycorrhizal fungal communities in areas highly impacted by anthropogenic disturbance and urbanization are less species rich or exhibit lower host root colonization rates when compared to those of less disturbed systems. Using a soil bioassay, we sampled the ectomycorrhizal fungal (EMF) communities associating with Quercus rubra (northern red oak) seedlings in soil collected from seven sites: two mature forest reference sites and five urban sites of varying levels of disturbance. Morphological and polymerase chain reaction-restriction fragment length polymorphism analyses of fungi colonizing root tips revealed that colonization rates and fungal species richness were significantly lower on root systems of seedlings grown in disturbed site soils. Analysis of similarity showed that EMF community composition was not significantly different among several urban site soils but did differ significantly between mature forest sites and all but one urban site. We identified a suite of fungal species that occurred across several urban sites. Lack of a diverse community of belowground mutualists could be a constraint on urban plant community development, especially of late-successional woodlands. Analysis of urban EMF communities can add to our understanding of urban plant community structure and should be addressed during ecological assessment before pragmatic decisions to restore habitats are framed.

Desarrollo del ensilado del alga Gracilaria chilensis para la alimentación del abalón rojo Haliotis rufescens

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Alfonso Mardones

2015-05-01

Full Text Available En Chile, el principal insumo usado como alimento para abalones son las algas Gracilaria chilensis y Macrocystis pyrifera. Estas algas experimentan una notable baja de disponibilidad en otoño e invierno, lo cual trae consigo un aumento considerable de los precios, al tener que depender del abastecimiento desde áreas cada vez más alejadas de los centros de cultivo de abalones y, eventualmente, generando impactos ecológicos indirectos en sus poblaciones. El objetivo fue elaborar y evaluar un ensilado del alga G. chilensis para la alimentación de abalón rojo (Haliotis rufescens, determinando la cantidad de lixiviados generados durante el proceso, el cambio en la composición proximal del alga, la preferencia y consumo del abalón rojo de ensilado de G. chilensis. Se logró un producto ensilado de buenas características físicas, químicas y de conservación, así como una buena aceptación por parte del abalón.

Habitat Preferences of Juvenile Abalone (Haliotis mariae Wood, 1828 Along the Dhofar Coast of Oman and Implications for Conservation

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Schalk Willem Petrus de Waal

2012-01-01

Full Text Available Surveys were conducted along the eastern Dhofar coast of Oman to investigate densities and habitat preferences of juvenile Haliotis mariae ( 50 cm Ø, respectively. B values were highest for urchins (6 times that for small boulders, and for boulders <50 cm Ø. B values for boulder habitats decreased as boulder size increased. Urchin utilisation by juvenile abalone as shelter ranged between geographic areas from a minimum of 15.5% to a maximum of 47.6%. The proportion of total habitat that is preferred by more than 97% of juvenile abalone found, including urchins and boulders < 50 cm Ø, comprises 29% of surveyed substratum. While the role urchins play on wild juvenile H. mariae has not proved vital, it is definitely significant. Although juvenile densities are low and are not currently limited by the availability of suitable habitat, it is crucial to identify and conserve those microhabitats that support recruitment of H. mariae. The abundance of these areas should be among the criteria used in selecting protected conservation areas.

Heterosis and combining ability: a diallel cross of three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino

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Deng, Yuewen; Liu, Xiao; Zhang, Guofan; Wu, Fucun

2010-11-01

We conducted a complete diallel cross among three geographically isolated populations of Pacific abalone Haliotis discus hannai Ino to determine the heterosis and the combining ability of growth traits at the spat stage. The three populations were collected from Qingdao (Q) and Dalian (D) in China, and Miyagi (M) in Japan. We measured the shell length, shell width, and total weight. The magnitude of the general combining ability (GCA) variance was more pronounced than the specific combining ability (SCA) variance, which is evidenced by both the ratio of the genetic component in total variation and the GCA/SCA values. The component variances of GCA and SCA were significant for all three traits ( P<0.05), indicating the importance of additive and non-additive genetic effects in determining the expression of these traits. The reciprocal maternal effects (RE) were also significant for these traits ( P<0.05). Our results suggest that population D was the best general combiner in breeding programs to improve growth traits. The DM cross had the highest heterosis values for all three traits.

Feeding preferences and the nutritional value of tropical algae for the abalone Haliotis asinina.

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Alex R Angell

Full Text Available Understanding the feeding preferences of abalone (high-value marine herbivores is integral to new species development in aquaculture because of the expected link between preference and performance. Performance relates directly to the nutritional value of algae--or any feedstock--which in turn is driven by the amino acid content and profile, and specifically the content of the limiting essential amino acids. However, the relationship between feeding preferences, consumption and amino acid content of algae have rarely been simultaneously investigated for abalone, and never for the emerging target species Haliotis asinina. Here we found that the tropical H. asinina had strong and consistent preferences for the red alga Hypnea pannosa and the green alga Ulva flexuosa, but no overarching relationship between protein content (sum of amino acids and preference existed. For example, preferred Hypnea and Ulva had distinctly different protein contents (12.64 vs. 2.99 g 100 g(-1 and the protein-rich Asparagopsis taxiformis (>15 g 100 g(-1 of dry weight was one of the least preferred algae. The limiting amino acid in all algae was methionine, followed by histidine or lysine. Furthermore we demonstrated that preferences can largely be removed using carrageenan as a binder for dried alga, most likely acting as a feeding attractant or stimulant. The apparent decoupling between feeding preference and algal nutritive values may be due to a trade off between nutritive values and grazing deterrence associated with physical and chemical properties.

Feeding Preferences and the Nutritional Value of Tropical Algae for the Abalone Haliotis asinina

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Angell, Alex R.; Pirozzi, Igor; de Nys, Rocky; Paul, Nicholas A.

2012-01-01

Understanding the feeding preferences of abalone (high-value marine herbivores) is integral to new species development in aquaculture because of the expected link between preference and performance. Performance relates directly to the nutritional value of algae – or any feedstock – which in turn is driven by the amino acid content and profile, and specifically the content of the limiting essential amino acids. However, the relationship between feeding preferences, consumption and amino acid content of algae have rarely been simultaneously investigated for abalone, and never for the emerging target species Haliotis asinina. Here we found that the tropical H. asinina had strong and consistent preferences for the red alga Hypnea pannosa and the green alga Ulva flexuosa, but no overarching relationship between protein content (sum of amino acids) and preference existed. For example, preferred Hypnea and Ulva had distinctly different protein contents (12.64 vs. 2.99 g 100 g−1) and the protein-rich Asparagopsis taxiformis (>15 g 100 g−1 of dry weight) was one of the least preferred algae. The limiting amino acid in all algae was methionine, followed by histidine or lysine. Furthermore we demonstrated that preferences can largely be removed using carrageenan as a binder for dried alga, most likely acting as a feeding attractant or stimulant. The apparent decoupling between feeding preference and algal nutritive values may be due to a trade off between nutritive values and grazing deterrence associated with physical and chemical properties. PMID:22719967

Transcriptome Analysis Revealed Changes of Multiple Genes Involved in Haliotis discus hannai Innate Immunity during Vibrio parahemolyticus Infection.

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Nam, Bo-Hye; Jung, Myunghee; Subramaniyam, Sathiyamoorthy; Yoo, Seung-il; Markkandan, Kesavan; Moon, Ji-Young; Kim, Young-Ok; Kim, Dong-Gyun; An, Cheul Min; Shin, Younhee; Jung, Ho-jin; Park, Jun-hyung

2016-01-01

Abalone (Haliotis discus hannai) is one of the most valuable marine aquatic species in Korea, Japan and China. Tremendous exposure to bacterial infection is common in aquaculture environment, especially by Vibrio sp. infections. It's therefore necessary and urgent to understand the mechanism of H. discus hannai host defense against Vibrio parahemolyticus infection. However studies on its immune system are hindered by the lack of genomic resources. In the present study, we sequenced the transcriptome of control and bacterial challenged H. discus hannai tissues. Totally, 138 MB of reference transcriptome were obtained from de novo assembly of 34 GB clean bases from ten different libraries and annotated with the biological terms (GO and KEGG). A total of 10,575 transcripts exhibiting the differentially expression at least one pair of comparison and the functional annotations highlight genes related to immune response, cell adhesion, immune regulators, redox molecules and mitochondrial coding genes. Mostly, these groups of genes were dominated in hemocytes compared to other tissues. This work is a prerequisite for the identification of those physiological traits controlling H. discus hannai ability to survive against Vibrio infection.

Transcriptome Analysis Revealed Changes of Multiple Genes Involved in Haliotis discus hannai Innate Immunity during Vibrio parahemolyticus Infection

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Nam, Bo-Hye; Jung, Myunghee; Subramaniyam, Sathiyamoorthy; Yoo, Seung-il; Markkandan, Kesavan; Moon, Ji-Young; Kim, Young-Ok; Kim, Dong-Gyun; An, Cheul Min; Shin, Younhee; Jung, Ho-jin; Park, Jun-hyung

2016-01-01

Abalone (Haliotis discus hannai) is one of the most valuable marine aquatic species in Korea, Japan and China. Tremendous exposure to bacterial infection is common in aquaculture environment, especially by Vibrio sp. infections. It’s therefore necessary and urgent to understand the mechanism of H. discus hannai host defense against Vibrio parahemolyticus infection. However studies on its immune system are hindered by the lack of genomic resources. In the present study, we sequenced the transcriptome of control and bacterial challenged H. discus hannai tissues. Totally, 138 MB of reference transcriptome were obtained from de novo assembly of 34 GB clean bases from ten different libraries and annotated with the biological terms (GO and KEGG). A total of 10,575 transcripts exhibiting the differentially expression at least one pair of comparison and the functional annotations highlight genes related to immune response, cell adhesion, immune regulators, redox molecules and mitochondrial coding genes. Mostly, these groups of genes were dominated in hemocytes compared to other tissues. This work is a prerequisite for the identification of those physiological traits controlling H. discus hannai ability to survive against Vibrio infection. PMID:27088873

Transcriptome Analysis Revealed Changes of Multiple Genes Involved in Haliotis discus hannai Innate Immunity during Vibrio parahemolyticus Infection.

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Bo-Hye Nam

Full Text Available Abalone (Haliotis discus hannai is one of the most valuable marine aquatic species in Korea, Japan and China. Tremendous exposure to bacterial infection is common in aquaculture environment, especially by Vibrio sp. infections. It's therefore necessary and urgent to understand the mechanism of H. discus hannai host defense against Vibrio parahemolyticus infection. However studies on its immune system are hindered by the lack of genomic resources. In the present study, we sequenced the transcriptome of control and bacterial challenged H. discus hannai tissues. Totally, 138 MB of reference transcriptome were obtained from de novo assembly of 34 GB clean bases from ten different libraries and annotated with the biological terms (GO and KEGG. A total of 10,575 transcripts exhibiting the differentially expression at least one pair of comparison and the functional annotations highlight genes related to immune response, cell adhesion, immune regulators, redox molecules and mitochondrial coding genes. Mostly, these groups of genes were dominated in hemocytes compared to other tissues. This work is a prerequisite for the identification of those physiological traits controlling H. discus hannai ability to survive against Vibrio infection.

Identification and characterization of Vibrio harveyi associated with diseased abalone Haliotis diversicolor.

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Jiang, Qingru; Shi, Liuyang; Ke, Caihuan; You, Weiwei; Zhao, Jing

2013-03-26

Mass mortality of farmed small abalone Haliotis diversicolor occurred in Fujian, China, from 2009 to 2011. Among isolates obtained from moribund abalones, the dominant species AP37 exhibited the strongest virulence. After immersion challenge with 106 CFU ml-1 of AP37, abalone mortalities of 0, 53 and 67% were induced at water temperatures of 20°C, 24°C, and 28°C, respectively. Following intramuscular injection, AP37 showed a low LD50 (median lethal concentration) value of 2.9 × 102 CFU g-1 (colony forming units per gram abalone wet body weight). The LT50 (median lethal time) values were 5.2 h for 1 × 106 CFU abalone-1, 8.4 h for 1 × 105 CFU abalone-1, and 21.5 h for 1 × 104 CFU abalone-1. For further analysis of virulence, AP37 was screened for the production of extracellular factors. The results showed that various factors including presence of flagella and production of extracellular enzymes, such as lipase, phospholipase and haemolysin, could be responsible for pathogenesis. Based on its 16S rRNA gene sequence, strain AP37 showed >98.8% similarity to Vibrio harveyi, V. campbellii, V. parahaemolyticus, V. alginolyticus, V. natriegens and V. rotiferianus, so it could not be identified by this method. However, multi-locus sequence analysis (MLSA) of concatenated sequences, including the rpoD, rctB, gyrB, toxR and pyrH genes, identified strain AP37 as V. harveyi. Phenotypic characters of AP37 were identified by API 20E. In antibiotic susceptibility tests, strain AP37 exhibited susceptibility to 7 antibiotics and resistance to 13. This is the first report of a V. harveyi-related species being linked with the mass mortality of adult abalone H. diversicolor in southern China.

iTRAQ-Based Identification of Proteins Related to Muscle Growth in the Pacific Abalone, Haliotis discus hannai

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Jianfang Huang

2017-10-01

Full Text Available The abalone Haliotis discus hannai is an important aquaculture species that is grown for human consumption. However, little is known of the genetic mechanisms governing muscle growth in this species, particularly with respect to proteomics. The isobaric tag for relative and absolute quantitation (iTRAQ method allows for sensitive and accurate protein quantification. Our study was the first to use iTRAQ-based quantitative proteomics to investigate muscle growth regulation in H. discus hannai. Among the 1904 proteins identified from six samples, 125 proteins were differentially expressed in large specimens of H. discus hannai as compared to small specimens. In the large specimens, 47 proteins were upregulated and 78 were downregulated. Many of the significant Kyoto Encyclopedia of Genes and Genomes (KEGG pathways, including these differentially expressed proteins, were closely related to muscle growth, including apoptosis, thyroid hormone signaling, regulation of the actin cytoskeleton, and viral myocarditis (p < 0.05. Our quantitative real-time polymerase chain reaction (qRT-PCR analyses suggested that the alterations in expression levels observed in the differentially expressed proteins were consistent with the alterations observed in the encoding mRNAs, indicating the repeatability of our proteomic approach. Our findings contribute to the knowledge of the molecular mechanisms of muscle growth in H. discus hannai.

The feasibility of bomb radiocarbon analysis to support an age-at-length relationship for red abalone, Haliotis rufescens Swainson in northern California

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Leaf, R T; Andrews, A H; Cailliet, G M; Brown, T A

2009-01-07

Analysis of bomb generated radiocarbon ({sup 14}C) changes in a red abalone, Haliotis rufescens Swainson shell was used to investigate age-at-length relationships derived from data from a previous multi-year, multi-site tag-recapture study. Shell carbonate was extracted from four successive growth trajectory locations in a single shell with a length of 251 mm MSL. Extraction locations were based on VBGF predictions and chosen to span the initial rise of the {sup 14}C-bomb pulse that is known to have occurred in surface ocean waters during 1958 {+-} 1 y in the northeast Pacific. The close temporal correspondence of the red abalone sample series to regional {Delta}{sup 14}C records demonstrated the utility of the technique for validating age-at-length relationships for the red abalone. The findings provided support for a mean VBGF derived age of 32 y (range 30 to 33 y) for the specimen; however, the analysis of {sup 14}C data indicated that the specimen could be older.

[Effects of simulated acid rain on water physiological characteristics of Myrica rubra seedlings].

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Yaho, Zhao-bin; Jiang, Hong; Yu, Shu-quan; Lu, Mei-juan

2011-08-01

Taking the seedlings of typical subtropical economic tree species Myrica rubra in Zhejiang Province as test materials, a pot experiment was conducted to study their water physiological characteristics under effects of simulated acid rain (pH 2.5 and pH 4.0), with water (pH 5.6) as the control. Season, year, and acid rain all had significant effects on the photosynthetic rate (Pn). Among the treatments, the Pn had a greater difference in summer than in spring and autumn, and was higher in treatment acid rain (pH 4.0). Season, year, acid rain, and the interactions of season and year and of the three factors had significant effects on the stomata conductance (Gs), and also, the Gs had a greater difference among the treatments in summer than in spring and autumn. Acid rain had inhibitory effect on Gs. Season, year, acid rain, and the interactions of season and year and of season and acid rain affected the transpiration rate (Tr) significantly. Same as Pn and Gs, the Tr had a greater difference among the treatments in summer than in spring and autumn. Acid rain (pH 2.5) had the strongest inhibitory effect on Tr. Acid rain and the interactions of season and year and of season and acid rain had significant effects on the water use efficiency (WUE), and acid rain (pH 2.5) had definitely positive effect on the WUE.

Evaluation of in vitro antidiabetic and antioxidant characterizations of Elettaria cardamomum (L.) Maton (Zingiberaceae), Piper cubeba L. f. (Piperaceae), and Plumeria rubra L. (Apocynaceae).

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Ahmed, Afnan Sh; Ahmed, Qamaruddin; Saxena, Anil Kumar; Jamal, Parveen

2017-01-01

Inhibition of intestinal α-amylase and α-glucosidase is an important strategy to regulate diabetes mellitus (DM). Antioxidants from plants are widely regarded in the prevention of diabetes. Fruits of Elettaria cardamomum (L.) Maton (Zingiberaceae) and Piper cubeba L. f. (Piperaceae) and flowers of Plumeria rubra L. (Apocynaceae) are traditionally used to cure DM in different countries. However, the role of these plants has been grossly under reported and is yet to receive proper scientific evaluation with respect to understand their traditional role in the management of diabetes especially as digestive enzymes inhibitors. Hence, methanol and aqueous extracts of the aforementioned plants were evaluated for their in vitro α-glucosidase and α-amylase inhibition at 1 mg/mL and quantification of their antioxidant properties (DPPH, FRAP tests, total phenolic and total flavonoids contents). In vitro optimization studies for the extracts were also performed to enhance in vitro biological activities. The % inhibition of α-glucosidase by the aqueous extracts of the fruits of E. cardamomum, P. cubeba and flowers of P. rubra were 10.41 (0.03), 95.19 (0.01), and -2.92 (0.03), while the methanol extracts exhibited % inhibition 13.73 (0.02), 92.77 (0.01), and -0.98 (0.01), respectively. The % inhibition of α-amylase by the aqueous extracts were 82.99 (0.01), 64.35 (0.01), and 20.28 (0.02), while the methanol extracts displayed % inhibition 39.93 (0.01), 31.06 (0.02), and 39.40 (0.01), respectively. Aqueous extracts displayed good in vitro antidiabetic and antioxidant activities. Moreover, in vitro optimization experiments helped to increase the α-glucosidase inhibitory activity of E. cardamomum. Our findings further justify the traditional claims of these plants as folk medicines to manage diabetes, however, through digestive enzymes inhibition effect.

Phytochemical Content of Some Black (Morus nigra L. and Purple (Morus rubra L. Mulberry Genotypes

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Murat Tosun

2010-01-01

Full Text Available Bright black (Morus nigra and purple mulberry (Morus rubra are particularly desirable fruits in Turkey. More recently, the interest in these bright black and purple mulberry fruits has also increased because of the popularization of healthy properties of these fruits. The study was carried out in 2008 aiming to determine the antioxidant activity (ferric reducing ability of plasma, FRAP, total phenolic, total anthocyanin, mineral, soluble solid, vitamin C, and total acid content of four black and four purple mulberry genotypes grown in Turkey. The results show that black mulberry genotypes have a higher bioactive content than purple mulberry genotypes. The average total phenolic content and total anthocyanins of black mulberry genotypes were 2149 μg of gallic acid equivalent (GAE per g and 719 μg of cyanidin 3-glucoside equivalent (Cy 3-glu per g of fresh mass. In purple mulberry, these values were for GAE 1690 μg/g and for Cy 3-glu 109 μg/g on fresh mass basis. The average antioxidant activity of black mulberry genotypes was also found to be higher than that of the purple ones according to FRAP assay (Trolox equivalent (TE per fresh mass of black and purple mulberries was 13.35 and 6.87 μmol/g, respectively.

Amplified fragment length polymorphism analysis to assess crossover interference and homozygosity in gynogenetic diploid Pacific abalone (Haliotis discus hannai).

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Nie, H-T; Li, Q; Kong, L-F

2014-06-01

Recombination analysis in gynogenetic diploids is a powerful tool for assessing the degree of inbreeding, investigating crossover events and understanding chiasma interference during meiosis. To estimate the marker-centromere recombination rate, the inheritance pattern of 654 amplified fragment length polymorphism (AFLP) markers was examined in the 72-h veliger larvae of two meiogynogenetic diploid families in the Pacific abalone (Haliotis discus hannai). The second-division segregation frequency (y) of the AFLP loci ranged from 0.00 to 0.96, with 23.9% of loci showing y-values higher than 0.67, evidencing the existence of interference. The average recombination frequency across the 654 AFLP loci was 0.45, allowing estimation of the fixation index of 0.55, indicating that meiotic gynogenesis could provide an effective means of rapid inbreeding in the Pacific abalone. The AFLP loci have a small proportion (4.4%) of y-values greater than 0.90, suggesting that a relatively low or intermediate degree of chiasma interference occurred in the abalone chromosomes. The information obtained in this study will enhance our understanding of the abalone genome and will be useful for genetic studies in the species. © 2014 Stichting International Foundation for Animal Genetics.

Evaluation of de novo assembly technique in the South African abalone Haliotis midae transcriptome: A comparison from Illumina and 454 systems

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Barbara Picone

2016-12-01

Full Text Available Next generation sequencing platforms have recently been used to rapidly characterize transcriptome sequences from a number of non-model organisms. The present study compares two of the most frequently used platforms, the Roche 454-pyrosequencing and the Illumina sequencing-by-synthesis (SBS, on the same RNA sample obtained from an intertidal gastropod mollusc species, Haliotis midae. All the sequencing reads were deposited in the Short Read Archive (SRA database are retrievable under the accession number [SRR071314 (Illumina Genome Analyzer II] and [SRR1737738, SRR1737737, SRR1737735, SRR1737734 (454 GS FLX] in the SRA database of NCBI. Three transcriptomes, composed of either pure 454 or Illumina reads or a mixture of read types (Hybrid, were assembled using CLC Genomics Workbench software. Illumina assemblies performed the best de novo transcriptome characterization in terms of contig length, whereas the 454 assemblies tended to improve the complete assembly of gene transcripts. Both the Hybrid and Illumina assemblies produced longer contigs covering more of the transcriptome than 454 assemblies. However, the addition of 454 significantly increased the number of genes annotated.

Predicting the distribution of commercially important invertebrate stocks under future climate.

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Bayden D Russell

Full Text Available The future management of commercially exploited species is challenging because techniques used to predict the future distribution of stocks under climate change are currently inadequate. We projected the future distribution and abundance of two commercially harvested abalone species (blacklip abalone, Haliotis rubra and greenlip abalone, H. laevigata inhabiting coastal South Australia, using multiple species distribution models (SDM and for decadal time slices through to 2100. Projections are based on two contrasting global greenhouse gas emissions scenarios. The SDMs identified August (winter Sea Surface Temperature (SST as the best descriptor of abundance and forecast that warming of winter temperatures under both scenarios may be beneficial to both species by allowing increased abundance and expansion into previously uninhabited coasts. This range expansion is unlikely to be realised, however, as projected warming of March SST is projected to exceed temperatures which cause up to 10-fold increases in juvenile mortality. By linking fine-resolution forecasts of sea surface temperature under different climate change scenarios to SDMs and physiological experiments, we provide a practical first approximation of the potential impact of climate-induced change on two species of marine invertebrates in the same fishery.

Marine environmental impact assessment of abalone, Haliotis discus hannai, cage farm in Wan-do, Republic of Korea

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Oh, Hyun-Taik; Jung, Rae-Hong; Cho, Yoon-Sik; Hwang, Dong-Woon; Yi, Yong-Min

2015-12-01

To assess the marine environmental impacts of abalone, Haliotis discus hannai, cage farms in Wan-do, we monitored the benthic environment on top of the sediment underneath cage farm stations and reference stations. We applied two methods for this assessment. One was the A- and B-investigation of the MOM system (Modeling-On fish farm-Monitoring) developed in Norway. The other was a general environmental monitoring method which is widely used. In this study, we found benthic animals in all samples that belonged to condition 1 which were based on group 1(presence of macrofauna) of the B-investigation method. The values of redox potential (group 2-pH, redox potential) in all samples were above +65 mV belonging to condition 1. Based on sensory results (group 3-gas, color, odor, thickness of deposits), five out of seven experiment samples showed condition 1 while stations 2 and 7 showed condition 2, which have been cultured for 10 years in semi-closed waters. As group 2 takes precedence over group 3, the level of the conditions for B-investigation results consequently showed condition 1 in all stations. We found that pollutants and trace metals in the sediment underneath cage farms were lower than the pollution standard. This led us to conclude that the environmental impacts of the cage farms in this study were not significant.

Long-term lead accumulation in abalone (Haliotis spp. ) fed on lead-treated brown algae (Egregia laevigata)

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Stewart, J; Schulz-Baldes, M

1976-01-01

In this study we assessed the amount of lead accumulated in the body of a grazing mollusc by transfer from its algal food in laboratory experiments, and compared these results with the amounts found in naturally occurring molluscs and seaweed. Near La Jolla, California (USA), where the concentration of lead in seawater is probably less than 0.08 ..mu..g 1/sup -1/, most of the naturally occurring Egregia laevigata contains less than 0.4 ..mu..g Pb g/sup -1/ wet weight. The total body masses, without shells, of juvenile Haliotis rufescens fed on this seaweed for 3 to 6 months showed similar concentrations. When, however, E. laevigata is placed for 1 to 6 days in seawater to which lead has been added (0.1 or 1.0 mg 1/sup -1/) both the seaweed and the abalone subsequently fed with it accumulate proportionally larger amounts of lead. After 6 months, young abalone fed on E. laevigata pretreated with 1.0 mg Pb 1/sup -1/ accumulated up to 21 ..mu..g Pb g/sup -1/ wet weight. This amount of lead had no apparent consequences on the growth or activity of the molluscs. Analyses of 6 different organs from adult abalone showed that the lead was selectively concentrated in the digestive gland. In the foot (muscle tissue), which is the part normally consumed by humans, only negligible amounts were found.

Genetic Characterization of Five Hatchery Populations of the Pacific Abalone (Haliotis discus hannai Using Microsatellite Markers

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Jeong-In Myeong

2011-07-01

Full Text Available The Pacific abalone, Haliotis discus hannai, is a popular food in Eastern Asia. Aquacultural production of this species has increased because of recent resource declines, the growing consumption, and ongoing government-operated stock release programs. Therefore, the genetic characterization of hatchery populations is necessary to maintain the genetic diversity of this species and to develop more effective aquaculture practices. We analyzed the genetic structures of five cultured populations in Korea using six microsatellite markers. The number of alleles per locus ranged from 15 to 64, with an average of 23.5. The mean observed and expected heterozygosities were 0.797 and 0.904, respectively. The inbreeding coefficient FIS ranged from 0.054 to 0.184 (mean FIS = 0.121 ± 0.056. The genetic differentiation across all populations was low but significant (overall FST = 0.009, P < 0.01. Pairwise multilocus FST tests, estimates of genetic distance, and phylogenetic and principal component analyses did not show a consistent relationship between geographic and genetic distances. These results could reflect extensive aquaculture, the exchange of breeds and eggs between hatcheries and/or genetic drift due to intensive breeding practices. Thus, for optimal resource management, the genetic variation of hatchery stocks should be monitored and inbreeding controlled within the abalone stocks that are being released every year. This genetic information will be useful for the management of both H. discus hannai fisheries and the aquaculture industry.

Construction of the BAC Library of Small Abalone (Haliotis diversicolor) for Gene Screening and Genome Characterization.

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Jiang, Likun; You, Weiwei; Zhang, Xiaojun; Xu, Jian; Jiang, Yanliang; Wang, Kai; Zhao, Zixia; Chen, Baohua; Zhao, Yunfeng; Mahboob, Shahid; Al-Ghanim, Khalid A; Ke, Caihuan; Xu, Peng

2016-02-01

The small abalone (Haliotis diversicolor) is one of the most important aquaculture species in East Asia. To facilitate gene cloning and characterization, genome analysis, and genetic breeding of it, we constructed a large-insert bacterial artificial chromosome (BAC) library, which is an important genetic tool for advanced genetics and genomics research. The small abalone BAC library includes 92,610 clones with an average insert size of 120 Kb, equivalent to approximately 7.6× of the small abalone genome. We set up three-dimensional pools and super pools of 18,432 BAC clones for target gene screening using PCR method. To assess the approach, we screened 12 target genes in these 18,432 BAC clones and identified 16 positive BAC clones. Eight positive BAC clones were then sequenced and assembled with the next generation sequencing platform. The assembled contigs representing these 8 BAC clones spanned 928 Kb of the small abalone genome, providing the first batch of genome sequences for genome evaluation and characterization. The average GC content of small abalone genome was estimated as 40.33%. A total of 21 protein-coding genes, including 7 target genes, were annotated into the 8 BACs, which proved the feasibility of PCR screening approach with three-dimensional pools in small abalone BAC library. One hundred fifty microsatellite loci were also identified from the sequences for marker development in the future. The BAC library and clone pools provided valuable resources and tools for genetic breeding and conservation of H. diversicolor.

Variation in rates of early development in Haliotis asinina generate competent larvae of different ages

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Jackson Daniel J

2012-02-01

Full Text Available Abstract Introduction Inter-specific comparisons of metazoan developmental mechanisms have provided a wealth of data concerning the evolution of body form and the generation of morphological novelty. Conversely, studies of intra-specific variation in developmental programs are far fewer. Variation in the rate of development may be an advantage to the many marine invertebrates that posses a biphasic life cycle, where fitness commonly requires the recruitment of planktonically dispersing larvae to patchily distributed benthic environments. Results We have characterised differences in the rate of development between individuals originating from a synchronised fertilisation event in the tropical abalone Haliotis asinina, a broadcast spawning lecithotrophic vetigastropod. We observed significant differences in the time taken to complete early developmental events (time taken to complete third cleavage and to hatch from the vitelline envelope, mid-larval events (variation in larval shell development and late larval events (the acquisition of competence to respond to a metamorphosis inducing cue. We also provide estimates of the variation in maternally provided energy reserves that suggest maternal provisioning is unlikely to explain the majority of the variation in developmental rate we report here. Conclusions Significant differences in the rates of development exist both within and between cohorts of synchronously fertilised H. asinina gametes. These differences can be detected shortly after fertilisation and generate larvae of increasingly divergent development states. We discuss the significance of our results within an ecological context, the adaptive significance of mechanisms that might maintain this variation, and potential sources of this variation.

Nitric oxide is not a negative regulator of metamorphic induction in the abalone Haliotis asinina

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Nobuo eUeda

2014-07-01

Full Text Available Nitric oxide (NO is a second messenger molecule synthesized by the enzyme nitric oxide synthase (NOS that requires the molecular chaperone heat shock protein 90 (HSP90 for normal enzymatic activity. Past studies have revealed that both NO and HSP90 act as negative regulators (repressors of metamorphosis in a diverse range of marine invertebrates, including several molluscan species. Here, we test the role of NO in the metamorphic induction of a vetigastropod mollusc, the tropical abalone Haliotis asinina. Specifically, we 1 test the effects of NO-manipulating pharmacological agents, 2 measure the temporal expression of NOS and HSP90 genes through metamorphosis, and 3 assess the spatial expression of NOS and HSP90 in larvae. We find that inhibition of NOS reduces rates of metamorphosis, indicating that NO facilitates, rather than represses, induction of metamorphosis in H. asinina. The marked increase in NOS expression in putative sensory cells localized to the anterior foot of competent larvae is consistent with NO as an inductive molecule for metamorphosis. In contrast to NOS, HSP90 transcript abundance decreases at competence and there is no evidence of NOS and HSP90 transcript co-localization. This study provides the first evidence of NO as an inductive facilitator of molluscan metamorphosis. Our experimental data suggest that NO modulates signals derived from live inductive substrates via the larval foot to regulate metamorphosis. Inter-specific comparisons of spatial NOS expression in molluscs suggest that the localized pattern of NOS or its protein product is related to the regulatory action of NO in metamorphosis.

Biomineral repair of abalone shell apertures.

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Cusack, Maggie; Guo, Dujiao; Chung, Peter; Kamenos, Nicholas A

2013-08-01

The shell of the gastropod mollusc, abalone, is comprised of nacre with an outer prismatic layer that is composed of either calcite or aragonite or both, depending on the species. A striking characteristic of the abalone shell is the row of apertures along the dorsal margin. As the organism and shell grow, new apertures are formed and the preceding ones are filled in. Detailed investigations, using electron backscatter diffraction, of the infill in three species of abalone: Haliotis asinina, Haliotis gigantea and Haliotis rufescens reveals that, like the shell, the infill is composed mainly of nacre with an outer prismatic layer. The infill prismatic layer has identical mineralogy as the original shell prismatic layer. In H. asinina and H. gigantea, the prismatic layer of the shell and infill are made of aragonite while in H. rufescens both are composed of calcite. Abalone builds the infill material with the same high level of biological control, replicating the structure, mineralogy and crystallographic orientation as for the shell. The infill of abalone apertures presents us with insight into what is, effectively, shell repair. Copyright © 2013 Elsevier Inc. All rights reserved.

Nitrogen fixation and growth response of Alnus rubra amended with low and high metal content biosolids Crescimento e fixação de nitrogênio por Alnus rubra cultivado sob fertilização com biosólidos com altos e baixos teores de metais

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Linda S. Gaulke

2006-08-01

Full Text Available Forest application of biosolids offers a potential environmentally friendly alternative to landfilling. This two-year investigation was designed to analyze the effects of elevated soil metal concentration resulting from the land application of biosolids on the symbiotic, nitrogen (N fixing relationship between Alnus rubra Bong. (red alder and Frankia. High metal biosolids and a modern-day composted biosolid applied at high loading rates of 250, 500, and 1000 Mg ha-1, were used to represent a worst-case scenario for metal contamination. The high metal biosolids were obtained before the current regulations were formulated and had been lagooned prior to use in this study. Total cadmium (Cd, lead (Pb and zinc (Zn in the high metal biosolids were 45, 958, and 2623 mg kg-1 respectively. These metal concentrations are above current regulatory limits in the US. The compost was made using biosolids that are currently produced and had Cd, Pb and Zn of 0.8, 20 and 160 mg kg-1 respectively. Trees were harvested and analyzed for rate of N fixation (as measured by acetylene reduction activity, biomass, and foliar metals. Soils were analyzed for available N, total carbon and N, pH and total Cd, Pb and Zn. Rates of N fixation were not affected by soil amendment. In year 2, shoot biomass of trees grown in both the compost and high metal amendments were higher than the control. Shoot biomass increased with increasing amount of compost amendments, but decreased with increasing amount of high metal amendments. There was no relationship between soil metal concentration and plant biomass. Foliar Cd and Pb were below detection for all trees and foliar Zn increased with increasing amount of both compost and high metal amendment, with concentrations of 249 mg kg-1 for trees grown in the compost amendment and 279 mg kg-1 for the high metal amendment. The results from this study indicate that the growth of A. rubra benefited from both types of biosolids used in the study

Effect of drying process assisted by high-pressure impregnation on protein quality and digestibility in red abalone (Haliotis rufescens).

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Cepero-Betancourt, Yamira; Oliva-Moresco, Patricio; Pasten-Contreras, Alexis; Tabilo-Munizaga, Gipsy; Pérez-Won, Mario; Moreno-Osorio, Luis; Lemus-Mondaca, Roberto

2017-10-01

Abalone (Haliotis spp.) is an exotic seafood product recognized as a protein source of high biological value. Traditional methods used to preserve foods such as drying technology can affect their nutritional quality (protein quality and digestibility). A 28-day rat feeding study was conducted to evaluate the effects of the drying process assisted by high-pressure impregnation (HPI) (350, 450, and 500 MPa × 5 min) on chemical proximate and amino acid compositions and nutritional parameters, such as protein efficiency ratio (PER), true digestibility (TD), net protein ratio, and protein digestibility corrected amino acid score (PDCAAS) of dried abalone. The HPI-assisted drying process ensured excellent protein quality based on PER values, regardless of the pressure level. At 350 and 500 MPa, the HPI-assisted drying process had no negative effect on TD and PDCAAS then, based on nutritional parameters analysed, we recommend HPI-assisted drying process at 350 MPa × 5 min as the best process condition to dry abalone. Variations in nutritional parameters compared to casein protein were observed; nevertheless, the high protein quality and digestibility of HPI-assisted dried abalones were maintained to satisfy the metabolic demands of human beings.

Alternative Splicing Profile and Sex-Preferential Gene Expression in the Female and Male Pacific Abalone Haliotis discus hannai.

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Kim, Mi Ae; Rhee, Jae-Sung; Kim, Tae Ha; Lee, Jung Sick; Choi, Ah-Young; Choi, Beom-Soon; Choi, Ik-Young; Sohn, Young Chang

2017-03-09

In order to characterize the female or male transcriptome of the Pacific abalone and further increase genomic resources, we sequenced the mRNA of full-length complementary DNA (cDNA) libraries derived from pooled tissues of female and male Haliotis discus hannai by employing the Iso-Seq protocol of the PacBio RSII platform. We successfully assembled whole full-length cDNA sequences and constructed a transcriptome database that included isoform information. After clustering, a total of 15,110 and 12,145 genes that coded for proteins were identified in female and male abalones, respectively. A total of 13,057 putative orthologs were retained from each transcriptome in abalones. Overall Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analyzed in each database showed a similar composition between sexes. In addition, a total of 519 and 391 isoforms were genome-widely identified with at least two isoforms from female and male transcriptome databases. We found that the number of isoforms and their alternatively spliced patterns are variable and sex-dependent. This information represents the first significant contribution to sex-preferential genomic resources of the Pacific abalone. The availability of whole female and male transcriptome database and their isoform information will be useful to improve our understanding of molecular responses and also for the analysis of population dynamics in the Pacific abalone.

Alternative Splicing Profile and Sex-Preferential Gene Expression in the Female and Male Pacific Abalone Haliotis discus hannai

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Mi Ae Kim

2017-03-01

Full Text Available In order to characterize the female or male transcriptome of the Pacific abalone and further increase genomic resources, we sequenced the mRNA of full-length complementary DNA (cDNA libraries derived from pooled tissues of female and male Haliotis discus hannai by employing the Iso-Seq protocol of the PacBio RSII platform. We successfully assembled whole full-length cDNA sequences and constructed a transcriptome database that included isoform information. After clustering, a total of 15,110 and 12,145 genes that coded for proteins were identified in female and male abalones, respectively. A total of 13,057 putative orthologs were retained from each transcriptome in abalones. Overall Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes (KEGG pathways analyzed in each database showed a similar composition between sexes. In addition, a total of 519 and 391 isoforms were genome-widely identified with at least two isoforms from female and male transcriptome databases. We found that the number of isoforms and their alternatively spliced patterns are variable and sex-dependent. This information represents the first significant contribution to sex-preferential genomic resources of the Pacific abalone. The availability of whole female and male transcriptome database and their isoform information will be useful to improve our understanding of molecular responses and also for the analysis of population dynamics in the Pacific abalone.

Splice variants of perlucin from Haliotis laevigata modulate the crystallisation of CaCO3.

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Tanja Dodenhof

Full Text Available Perlucin is one of the proteins of the organic matrix of nacre (mother of pearl playing an important role in biomineralisation. This nacreous layer can be predominately found in the mollusc lineages and is most intensively studied as a compound of the shell of the marine Australian abalone Haliotis laevigata. A more detailed analysis of Perlucin will elucidate some of the still unknown processes in the complex interplay of the organic/inorganic compounds involved in the formation of nacre as a very interesting composite material not only from a life science-based point of view. Within this study we discovered three unknown Perlucin splice variants of the Australian abalone H. laevigata. The amplified cDNAs vary from 562 to 815 base pairs and the resulting translation products differ predominantly in the absence or presence of a varying number of a 10 mer peptide C-terminal repeat. The splice variants could further be confirmed by matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-ToF MS analysis as endogenous Perlucin, purified from decalcified abalone shell. Interestingly, we observed that the different variants expressed as maltose-binding protein (MBP fusion proteins in E. coli showed strong differences in their influence on precipitating CaCO3 and that these differences might be due to a splice variant-specific formation of large protein aggregates influenced by the number of the 10 mer peptide repeats. Our results are evidence for a more complex situation with respect to Perlucin functional regulation by demonstrating that Perlucin splice variants modulate the crystallisation of calcium carbonate. The identification of differentially behaving Perlucin variants may open a completely new perspective for the field of nacre biomineralisation.

Feeding, growth, and survival of post-larval abalone Haliotis asinina on different benthic diatoms

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Emmanuel C. Capinpin, Jr.

2007-12-01

Full Text Available The feeding behavior, digestive efficiency, growth, and survival of post-larval abalone Haliotis asininafed with 5 species of locally isolated benthic diatom strains (Navicula mollis, N. ramosissima, Stauroneissp., Pleurosigma sp., and Cocconeis sp. were examined in the laboratory. Two 15-day feeding trialsusing 1 mm post-larvae were conducted. No significant differences were observed in sizes of post-larvalabalone after 15 days in all diatom treatments (P>0.05. However, in both trials, Cocconeis sp. resulted inhigh survival rates (88.9±5.6% and 80.0±20.0% for Trials 1 and 2, respectively. Cocconeis sp. wasefficiently digested by post-larval abalone, with most of the cells being ruptured during ingestion and/orpassage through the gut. One diatom strain, Pleurosigma sp., resulted to a high survival but producedthe slowest growth rate (<10 ìm.d-1 SL. It was probably not ingested easily during the experiment due toits large size or mobility. For the other diatom strains, N. mollis and N. ramosissima, most cells passedthrough the gut with the cells left intact. Stauroneis sp. is highly digestible, but did not result to highsurvival, although the remaining live post-larval abalone fed on this diatom as well as on N. mollis grewfaster during the second week of both feeding trials. N. ramosissima resulted to poorest survival rate(<10% due to its poor digestibility. Only Cocconeis sp. showed a fairly high growth rate, digestionefficiency, and survival rate. N. mollis which gave a fairly high survival rate and Stauroneis may be addedtowards the later stages of post-larval rearing as well as other large diatoms. The digestion efficiency ofdiatom strains is considered an important factor determining its dietary value, but other factors may alsobe important such as volume contents, biochemical composition, and other physical characteristics.

Molecular cloning and characterization of prohormone convertase 1 gene in abalone (Haliotis diversicolor supertexta).

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Zhou, Jin; Cai, Zhong-hua

2010-03-01

Prohormone convertases (PCs) are calcium-dependent serine endoproteases of the subtilisin family that play a key role in the posttranslational processing of precursors for bioactive peptides. In this study, the cDNA of PC1 from abalone (Haliotis diversicolor supertexta) was cloned and sequenced. The PC1 cDNA consisted of 2216 bp with an open reading frame of 2010 bp encoding a 670 amino acid peptide. Comparative structural analysis revealed that abalone PC1 shared high similarity and identity with most PC counterparts. The profile of deduced peptide of PC1 was composed of an N-terminal signal peptide, a prosegment domain, a catalytic domain and a P domain, which were common in many species. Sequence analysis indicated that the abalone PC1 was highly conserved in catalytic domain, including three conserved serine catalytic signatures that comprised a catalytic triad active center. Also conserved were the potential cleavage site for release of the mature peptide, a cognate integrin binding site RGD in P domain, and four cysteine residues involved in forming an intrachain disulfide bridge. To further investigate the functions of PC1 in abalone, real-time quantitative PCR was performed to determine the expression level of this gene at three different reproduction stages (i.e. pre-, during- and post-breeding). Results indicated that PC1 was expressed throughout the three stages but the expression levels varied with the timepoints and different tissues in abalone. The expression levels of PC1 in digestive gland were much higher than those of the gonad. In female abalone, the expression of PC1 was higher at pre-breeding and during-breeding stages (Pabalone reproduction process (e.g. spawning or sperming). PC1 is a potential prohormone processing enzyme and it may play a critical role in abalone physiological processes related to reproduction. 2009 Elsevier Inc. All rights reserved.

Nocardia rubra cell-wall skeleton promotes CD4+ T cell activation and drives Th1 immune response.

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Wang, Guangchuan; Wu, Jie; Miao, Miao; Dou, Heng; Nan, Ning; Shi, Mingsheng; Yu, Guang; Shan, Fengping

2017-08-01

Several lines of evidences have shown that Nocardia rubra cell wall skeleton (Nr-CWS) has immunoregulatory and anti-tumor activities. However, there is no information about the effect of Nr-CWS on CD4 + T cells. The aim of this study was to explore the effect of Nr-CWS on the phenotype and function of CD4 + T cells. Our results of in vitro experiments showed that Nr-CWS could significantly up-regulate the expression of CD69 and CD25 on CD4 + T cells, promote the proliferation of CD4 + T cells, increase the production of IFN-γ, TNF-α and IL-2 in the supernatants, but has no significant effect on the apoptosis and death of CD4 + T cells. Results of in vivo experiments showed that Nr-CWS could promote the proliferation of CD4 + T cells, and increase the production of IL-2, IFN-γ and TNF-α (Th1 type cytokines). These data suggest that Nr-CWS can enhance the activation of CD4 + T cells, promote the proliferation of CD4 + T cells and the differentiation of CD4 + T cells to Th1 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural characterization and expression analysis of a beta-thymosin homologue (Tβ) in disk abalone, Haliotis discus discus.

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Kasthuri, Saranya Revathy; Premachandra, H K A; Umasuthan, Navaneethaiyer; Whang, Ilson; Lee, Jehee

2013-09-15

Repertoires of proteins and small peptides play numerous physiological roles as hormones, antimicrobial peptides, and cellular signaling factors. The beta-thymosins are a group of small acidic peptides involved in processes such as actin sequestration, neuronal development, wound healing, tissue repair, and angiogenesis. Recent characterization of the beta thymosins as immunological regulators in invertebrates led to our identification and characterization of a beta-thymosin homologue (Tβ) from Haliotis discus discus. The cDNA possessed an ORF of 132 bp encoding a protein of 44 amino acids with a molecular mass of 4977 Da. The amino acid sequence shows high identity with another molluskan beta-thymosin and has a characteristic actin binding motif (LKKTET) and glutamyl donors. Phylogenetic analysis showed a close relationship with molluskan homologues, as well as its distinct identity and common ancestral origin. Genomic analysis revealed a 3 exon-2 intron structure similar to the other homologues. In silico promoter analysis also revealed significant transcription factor binding sites, providing evidence for the expression of this gene under different cellular conditions, including stress or pathogenic attack. Tissue distribution profiling revealed a ubiquitous presence in all the examined tissues, but with the highest expression in mantle and hemocyte. Immune challenge with lipopolysaccharide, poly I:C and Vibrio parahemolyticus induced beta-thymosin expression in gill and hemocytes, affirming an immune-related role in invertebrates. Copyright © 2013 Elsevier B.V. All rights reserved.

Biomedical evaluation of free-ranging red ruffed lemurs (Varecia rubra) within the Masoala National Park, Madagascar.

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Dutton, Christopher J; Junge, Randall E; Louis, Edward E

2008-03-01

Complete health assessments were performed on 22 adult red ruffed lemurs (Varecia rubra), comprising nine males and 13 females, found within the Masoala National Park in northeast Madagascar. Each animal was anesthetized using tiletamine and zolazepam and underwent a thorough physical examination, including measurement of its weight and vital signs; blood collection for hematology, plasma total protein concentration, serum chemistries, fat-soluble vitamins, trace minerals, assessment of iron metabolism, toxoplasmosis serology, viral serologies, and examination for hemoparasites; fecal collection for bacterial culture and parasite examination; and collection of a representative number of any ectoparasites. Comparison of blood values with those of captive lemurs demonstrated a number of significant differences thought to be associated with physiologic state (e.g., reproductive stage and stress), hydration, and diet. There was no evidence of serious infectious diseases, and hemoparasites were not detected. The enteric flora appeared unremarkable; however, results may have been skewed toward more cold-tolerant bacteria. The fecal parasite burden was low. Lemurostrongylus spp. was identified in two of the lemurs, and there were moderate numbers of Laelapidae mites present on approximately one third of the lemurs. This study demonstrated the substantial amount of data that can be collected from free-ranging populations, considered invaluable in the management of captive populations, in reducing the incidence of captivity-related diseases, and in the risk assessment associated with reintroduction programs.

Ferritin from the Pacific abalone Haliotis discus hannai: Analysis of cDNA sequence, expression, and activity.

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Qiu, Reng; Kan, Yunchao; Li, Dandan

2016-02-01

Ferritin plays an important role in iron homeostasis due to its ability to bind and sequester large amounts of iron. In this study, the gene encoding a ferritin (HdhFer2) was cloned from Pacific abalone (Haliotis discus hannai). The full-length cDNA of HdhFer2 contains a 5'-UTR of 121 bp, an ORF of 516 bp, and a 3'-UTR of 252 bp with a polyadenylation signal sequence of AATAAA and a poly(A) tail. It also contains a 31 bp iron-responsive element (IRE) in the 5'-UTR position, which is conserved in many ferritins. HdhFer2 consists of 171 amino acid residues with a predicted molecular weight (MW) ∼19.8 kDa and a theoretical isoelectric point (PI) of 4.84. The deduced amino acid sequence of HdhFer2 contains two ferritin iron-binding region signatures (IBRSs). HdhFer2 mRNA was detected in a wide range of tissues and was dominantly expressed in the gill. Infection with the bacterial pathogen Vibrio anguillarum significantly upregulated HdhFer2 expression in a time-dependent manner. Recombinant HdhFer2 (rHdhFer2) purified from Escherichia coli was able to bind ferrous iron in a concentration-dependent manner. In summary, these results suggest that HdhFer2 is a crucial protein in the iron-withholding defense system, and plays an important role in the innate immune response of abalone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of air-temperature and diet composition on the drying process of pellets for japanese abalone (Haliotis discus hannai feeding

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Antonio Vega-Gálvez

2011-09-01

Full Text Available The aim of this research was to study the effect of air-temperature and diet composition on the mass transfer kinetics during the drying process of pellets used for Japanese Abalone (Haliotis discus hannai feeding. In the experimental design, three temperatures were used for convective drying, as well as three different diet compositions (Diets A, B and C, in which the amount of fishmeal, spirulin, algae, fish oil and cornstarch varied. The water diffusion coefficient of the pellets was determined using the equation of Fick's second law, which resulted in values between 0.84-1.94×10-10 m²/s. The drying kinetics was modeled using Page, Modified Page, Root of time, Exponential, Logarithmic, Two-Terms, Modified Henderson-Pabis and Weibull models. In addition, two new models, referred to as 'Proposed' models 1 and 2, were used to simulate this process. According to the statistical tests applied, the models that best fitted the experimental data were Modified Henderson-Pabis, Weibull and Proposed model 2, respectively. Bifactorial analysis of variance ANOVA showed that Diet A (fishmeal 44%, spirulin 9%, fish oil 1% and cornstarch 36% presented the highest diffusion coefficient values, which were favored by the temperature increase in the drying process.

Genomic Characterization of a Novel Phage Found in Black Abalone (Haliotis cracherodii) Infected with Withering Syndrome

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Closek, C. J.; Langevin, S.; Burge, C. A.; Crosson, L.; White, S.; Friedman, C. S.

2016-02-01

Withering syndrome (WS), caused by the bacterium Candidatus Xenohaliotis californiensis, a Rickettsia-like organism (RLO), infects many species of abalone. Black abalone (Haliotis cracherodii), one of two endangered species of abalone, has experienced high population losses along the California coast due to WS. Recently, we observed reduced pathogenicity and mortality events in RLO-infected abalone when a novel bacteriophage (phage) was also present. To better understand phage-bacterium dynamics and develop more informative diagnostic tools, we sequenced the genome of the novel phage associated with the RLO responsible for WS. Metagenomic sequencing libraries were prepared with extracted genomic DNA from two experimentally infected H. cracherodii and phage sequences were enriched using hydroxyapatite chromatography normalization. Normalized libraries were individually barcoded and sequenced with Illumina MiSeq. Raw sequence reads were processed using VIrominer and de novo assembly produced one single phage-like contig (35.7Kb) from the experimentally infected abalone. This highly divergent genome had closest homology with a virus associated with abalone shriveling syndrome (SS). Of the 34 predicted ORFs, overlapping homology with the SS virus ranged from 20-72%, demonstrating the phage sequenced is genetically distinct from any known phage. The phage-like sequences represented a significant portion of the total reads sequenced ( 2 million of the 12 million paired-end reads; 17%) and we obtained 94,000X coverage across the novel phage genome. Beyond characterization of this novel phage, which appears to reduce pathogenicity of the RLO, the genome enabled us to develop quantitative PCR and in situ hybridization assays as diagnostic tools. These tools allow us to detect and quantify this phage in the endangered H. cracherodii.

Cathepsin L is an immune-related protein in Pacific abalone (Haliotis discus hannai)--Purification and characterization.

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Shen, Jian-Dong; Cai, Qiu-Feng; Yan, Long-Jie; Du, Cui-Hong; Liu, Guang-Ming; Su, Wen-Jin; Ke, Caihuan; Cao, Min-Jie

2015-12-01

Cathepsin L, an immune-related protein, was purified from the hepatopancreas of Pacific abalone (Haliotis discus hannai) by ammonium sulfate precipitation and column chromatographies of SP-Sepharose and Sephacryl S-200 HR. Purified cathepsin L appeared as two bands with molecular masses of 28.0 and 28.5 kDa (namely cathepsin La and Lb) on SDS-PAGE under reducing conditions, suggesting that it is a glycoprotein. Peptide mass fingerprinting (PMF) analysis revealed that peptide fragments of 95 amino acid residues was high similarity to cathepsin L of pearl oyster (Pinctada fucata). The optimal temperature and pH of cathepsin L were 35 °C and pH 5.5. Cathepsin L was particularly inhibited by cysteine proteinase inhibitors of E-64 and leupeptin, while it was activated by metalloproteinase inhibitors EDTA and EGTA. The full-length cathepsin L cDNA was further cloned from the hepatopancreas by rapid PCR amplification of cDNA ends (RACE). The open reading frame of the enzyme was 981 bp, encoding 327 amino acid residues, with a conserved catalytic triad (Cys134, His273 and Asn293), a potential N-glycosylation site and conserved ERFNIN, GNYD, and GCGG motifs, which are characteristics of cathepsin L. Western blot and proteinase activity analysis revealed that the expression and enzyme activity of cathepsin L were significantly up-regulated in hepatopancreas at 8 h following Vibrio parahaemolyticus infection, demonstrating that cathepsin L is involved in the innate immune system of abalone. Our present study for the first time reported the purification, characterization, molecular cloning, and tissue expression of cathepsin L in abalone. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reduced translocation of current photosynthate precedes changes in gas exchange for Quercus rubra seedlings under flooding stress.

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Sloan, Joshua L; Islam, M Anisul; Jacobs, Douglass F

2016-01-01

Northern red oak (Quercus rubra L.) seedlings are frequently planted on suboptimal sites in their native range in North America, subjecting them to environmental stresses, such as flooding, for which they may not be well adapted. Members of the genus Quercus exhibit a wide range of responses to flooding, and responses of northern red oak to flooding remain inadequately described. To better understand the physiological effects of root system inundation in post-transplant northern red oak seedlings and the effects of flooding on endogenous patterns of resource allocation within the plant, we observed the effects of short-term flooding initiated at the linear shoot growth stage on net photosynthetic rates, dark respiration, chlorophyll fluorescence (Fv/Fm) and translocation of (13)C-labeled current photosynthate. Downward translocation of current photosynthate declined after 4 days of flooding and was the first measured physiological response to flooding; net photosynthetic rates decreased and dark respiration rates increased after 7 days of flooding. Short-term flooding did not affect maximal potential efficiency of photosystem II (Fv/Fm). The finding that decreased downward translocation of (13)C-labeled current photosynthate preceded reduced net photosynthesis and increased dark respiration during flooding suggests the occurrence of sink-limited photosynthesis under these conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Transcriptome-Wide Single Nucleotide Polymorphisms (SNPs for Abalone (Haliotis midae: Validation and Application Using GoldenGate Medium-Throughput Genotyping Assays

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Rouvay Roodt-Wilding

2013-09-01

Full Text Available Haliotis midae is one of the most valuable commercial abalone species in the world, but is highly vulnerable, due to exploitation, habitat destruction and predation. In order to preserve wild and cultured stocks, genetic management and improvement of the species has become crucial. Fundamental to this is the availability and employment of molecular markers, such as microsatellites and Single Nucleotide Polymorphisms (SNPs . Transcriptome sequences generated through sequencing-by-synthesis technology were utilized for the in vitro and in silico identification of 505 putative SNPs from a total of 316 selected contigs. A subset of 234 SNPs were further validated and characterized in wild and cultured abalone using two Illumina GoldenGate genotyping assays. Combined with VeraCode technology, this genotyping platform yielded a 65%−69% conversion rate (percentage polymorphic markers with a global genotyping success rate of 76%−85% and provided a viable means for validating SNP markers in a non-model species. The utility of 31 of the validated SNPs in population structure analysis was confirmed, while a large number of SNPs (174 were shown to be informative and are, thus, good candidates for linkage map construction. The non-synonymous SNPs (50 located in coding regions of genes that showed similarities with known proteins will also be useful for genetic applications, such as the marker-assisted selection of genes of relevance to abalone aquaculture.

Transcriptome-wide single nucleotide polymorphisms (SNPs) for abalone (Haliotis midae): validation and application using GoldenGate medium-throughput genotyping assays.

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Bester-Van Der Merwe, Aletta; Blaauw, Sonja; Du Plessis, Jana; Roodt-Wilding, Rouvay

2013-09-23

Haliotis midae is one of the most valuable commercial abalone species in the world, but is highly vulnerable, due to exploitation, habitat destruction and predation. In order to preserve wild and cultured stocks, genetic management and improvement of the species has become crucial. Fundamental to this is the availability and employment of molecular markers, such as microsatellites and single nucleotide (SNPs). Transcriptome sequences generated through sequencing-by-synthesis technology were utilized for the in vitro and in silico identification of 505 putative SNPs from a total of 316 selected contigs. A subset of 234 SNPs were further validated and characterized in wild and cultured abalone using two Illumina GoldenGate genotyping assays. Combined with VeraCode technology, this genotyping platform yielded a 65%-69% conversion rate (percentage polymorphic markers) with a global genotyping success rate of 76%-85% and provided a viable means for validating SNP markers in a non-model species. The utility of 31 of the validated SNPs in population structure analysis was confirmed, while a large number of SNPs (174) were shown to be informative and are, thus, good candidates for linkage map construction. The non-synonymous SNPs (50) located in coding regions of genes that showed similarities with known proteins will also be useful for genetic applications, such as the marker-assisted selection of genes of relevance to abalone aquaculture.

Physiological Adjustments of Leaf Respiration to Atmospheric Warming in Betula alleghaniensis and Quercus rubra

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Vollmar, A.; Gunderson, C.

2006-01-01

Global air temperatures are predicted to rise 1° to 4.5° Celsius by the year 2100. This climatic change is expected to have a great effect on the succession and migration of temperate deciduous forest species. Most physiologically based models of forest response to climatic change focus on the ecosystems as a whole instead of on individual tree species, assuming that the effects of warming on respiration are generally the same for each species, and that processes can not adjust to a changing climate. Experimental data suggest that physiological adjustments are possible, but there is a lack of data in deciduous species. In order to correctly model the effects of climate change on temperate species, species-specific respiration acclimation (adjustment) to rising temperatures is being determined in this experiment. Two temperate deciduous tree species Betula alleghaniensis (BA) and Quercus rubra (QR) were grown over a span of four years in open-top chambers and subjected to two different temperature treatments; ambient and ambient plus 4° Celsius (E4). Between 0530 hours and 1100 hours, respiration was measured over a range of leaf temperatures on several comparable, fully expanded leaves in each treatment. Circular punches were taken from the leaves and dried at 60°C to determine leaf mass per area (LMA). Respiration rates at a common temperature decreased by 15-18% in both species, and the entire resperation versus temperature curve shifted by at least 4°C, indicating a large degree of physiological acclimation. Foliar mass per area decreased with increasing growth temperature for both species. It can be concluded that there is a relationship between leaf respiration and foliar mass as it relates to respiratory acclimation, and that these two species had similar patterns of adjustment to warming.

Effects of temperature and salinity on survival, growth and DNA methylation of juvenile Pacific abalone, Haliotis discus hannai Ino

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Kong, Ning; Liu, Xiao; Li, Junyuan; Mu, Wendan; Lian, Jianwu; Xue, Yanjie; Li, Qi

2017-09-01

Temperature and salinity are two of the most potent abiotic factors influencing marine mollusks. In this study, we investigated the individual and combined effects of temperature and salinity on the survival and growth of juvenile Pacific abalone, Haliotis discus hannai Ino, and also examined the DNA methylation alteration that may underpin the phenotypic variation of abalone exposed to different rearing conditions. The single-factor data showed that the suitable ranges of temperature and salinity were 16-28°C at a constant salinity of 32, and 24-40 at a constant temperature of 20°C, respectively. The two-factor data indicated that both survival and growth were significantly affected by temperature, salinity and their interaction. The optimal temperature-salinity combination for juveniles was 23-25°C and 30-36. To explore environment-induced DNA methylation alteration, the methylation-sensitive amplified polymorphism (MSAP) technique was used to analyze the genomic methylation profiles of abalone reared in optimal and adverse conditions. Neither temperature nor salinity induced evident changes in the global methylation level, but 67 and 63 differentially methylated loci were identified in temperature and salinity treatments, respectively. The between-group eigen analysis also showed that both temperature and salinity could induce epigenetic differentiation in H. discus hannai Ino. The results of our study provide optimal rearing conditions for juvenile H. discus hannai Ino, and represent the first step toward revealing the epigenetic regulatory mechanism of abalone in response to thermal and salt stresses.

Acclimation-dependent expression of heat shock protein 70 in Pacific abalone ( Haliotis discus hannai Ino) and its acute response to thermal exposure

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Li, Jiaqi; He, Qingguo; Sun, Hui; Liu, Xiao

2012-01-01

Heat shock protein 70 (Hsp70) is one important member of heat shock protein (Hsp) family that is responsible for various stresses, especially thermal stress. Here we examined the response of Hsp70 gene to both chronic and acute thermal exposure in Pacific abalone ( Haliotis discus hannai Ino). For the chronic exposure, abalones were maintained at 8, 12, 20, and 30°C for four months and their mRNA levels were measured. The highest mRNA level of Hsp70 gene relative to actin gene was detected in the 30°C-acclimated group, followed by the 8°C-acclimated group and then the 12°C- and 20°C-acclimated groups. After the long-term acclimation, gills from each of the above acclimation groups were dissected and exposed to different temperatures between 8°C and 38°C for 30 min. Hsp70 expression in gills acclimated to different temperatures responded differentially to the same temperature exposure. The incubation temperature that induced maximum Hsp70 mRNA expression was higher in the higher temperature acclimation groups than lower temperature groups. Pacific abalones could alter the expression pattern of Hsp70 gene according to environmental thermal conditions, through which they deal with the stress of thermal variations.

Marked changes in neuropeptide expression accompany broadcast spawnings in the gastropod Haliotis asinina

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York Patrick S

2012-05-01

Full Text Available Abstract Introduction A huge diversity of marine species reproduce by synchronously spawning their gametes into the water column. Although this species-specific event typically occurs in a particular season, the precise time and day of spawning often can not be predicted. There is little understanding of how the environment (e.g. water temperature, day length, tidal and lunar cycle regulates a population’s reproductive physiology to synchronise a spawning event. The Indo-Pacific tropical abalone, Haliotis asinina, has a highly predictable spawning cycle, where individuals release gametes on the evenings of spring high tides on new and full moons during the warmer half of the year. These calculable spawning events uniquely allow for the analysis of the molecular and cellular processes underlying reproduction. Here we characterise neuropeptides produced in H. asinina ganglia that are known in egg-laying molluscs to control vital aspects of reproduction. Results We demonstrate that genes encoding APGWamide, myomodulin, the putative proctolin homologue whitnin, FMRFamide, a schistosomin-like peptide (SLP, a molluscan insulin-related peptide (MIP and a haliotid growth-associated peptide (HGAP all are differentially expressed in the anterior ganglia during the two week spawning cycle in both male and female abalone. Each gene has a unique and sex-specific expression profile. Despite these differences, expression levels in most of the genes peak at or within 12 h of the spawning event. In contrast, lowest levels of transcript abundance typically occurs 36 h before and 24 h after spawning, with differences in peak and low expression levels being most pronounced in genes orthologous to known molluscan reproduction neuromodulators. Conclusions Exploiting the predictable semi-lunar spawning cycle of the gastropod H. asinina, we have identified a suite of evolutionarily-conserved, mollusc-specific and rapidly-evolving neuropeptides that appear to

Epipodial Tentacle Gene Expression and Predetermined Resilience to Summer Mortality in the Commercially Important Greenlip Abalone, Haliotis laevigata.

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Shiel, Brett P; Hall, Nathan E; Cooke, Ira R; Robinson, Nicholas A; Strugnell, Jan M

2017-04-01

"Summer mortality" is a phenomenon that occurs during warm water temperature spikes that results in the mass mortality of many ecologically and economically important mollusks such as abalone. This study aimed to determine whether the baseline gene expression of abalone before a laboratory-induced summer mortality event was associated with resilience to summer mortality. Tentacle transcriptomes of 35 greenlip abalone (Haliotis laevigata) were sequenced prior to the animals being exposed to an increase in water temperature-simulating conditions which have previously resulted in summer mortality. Abalone derived from three source locations with different environmental conditions were categorized as susceptible or resistant to summer mortality depending on whether they died or survived after the water temperature was increased. We detected two genes showing significantly higher expression in resilient abalone relative to susceptible abalone prior to the laboratory-induced summer mortality event. One of these genes was annotated through the NCBI non-redundant protein database using BLASTX to an anemone (Exaiptasia pallida) Transposon Ty3-G Gag Pol polyprotein. Distinct gene expression signatures were also found between resilient and susceptible abalone depending on the population origin, which may suggest divergence in local adaptation mechanisms for resilience. Many of these genes have been suggested to be involved in antioxidant and immune-related functions. The identification of these genes and their functional roles have enhanced our understanding of processes that may contribute to summer mortality in abalone. Our study supports the hypothesis that prestress gene expression signatures are indicative of the likelihood of summer mortality.

Molecular characterization and expression analysis of a heat shock protein 90 gene from disk abalone (Haliotis discus).

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Wang, Ning; Whang, Ilson; Lee, Jae-Seong; Lee, Jehee

2011-06-01

Heat shock protein 90s (hsp90s) are chaperones that contribute to the proper folding of cellular proteins and help animals cope with the cellular protein damages in stress conditions. In this study, an hsp90 gene was isolated from disc abalone (Haliotis discus). The complete nucleotide sequence of the hsp90 gene contains an open reading frame of 2,184 base pairs, encoding an 84 kDa protein. Disk abalone hsp90 shares high sequence similarity with other hsp90 family proteins. Although the phylogenetic analysis did not classify it into the hsp90α group, the inductivity of this gene was confirmed by heat shock and lipopolysaccharide (LPS) challenge test. Disk abalone hsp90 gene displayed a rapid and reversible induction response to both an exposure of typical heat shock and the LPS challenge. Once given the sublethal heat shock treatment, the transcription of disk abalone hsp90 gene was significantly up-regulated. With a recovery of 12 h, the transcription of disk abalone hsp90 gene gradually attenuated to the control level. These observations reflected the feedback regulation of abalone heat shock responses faithfully. In response to LPS challenge, the transcription of disk abalone hsp90 gene was significantly increased within 2 h and it approached maximum induction at 4 h later and recovered finally the reference level in 24 h. Take all together, the cloning and expression analysis of disk abalone hsp90 gene provided useful molecular information of abalone responses in stress conditions and potential ways to monitor the chronic stressors in abalone culture environments and diagnose the animal health status.

Identification of normalization factors for quantitative real-time RT-PCR analysis of gene expression in Pacific abalone Haliotis discus hannai

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Qiu, Reng; Sun, Boguang; Fang, Shasha; Sun, Li; Liu, Xiao

2013-03-01

Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is widely used in studies of gene expression. In most of these studies, housekeeping genes are used as internal references without validation. To identify appropriate reference genes for qRT-PCR in Pacific abalone Haliotis discus hannai, we examined the transcription stability of six housekeeping genes in abalone tissues in the presence and absence of bacterial infection. For this purpose, abalone were infected with the bacterial pathogen Vibrio anguillarum for 12 h and 48 h. The mRNA levels of the housekeeping genes in five tissues (digestive glands, foot muscle, gill, hemocyte, and mantle) were determined by qRT-PCR. The PCR data was subsequently analyzed with the geNorm and NormFinder algorithms. The results show that in the absence of bacterial infection, elongation factor-1-alpha and beta-actin were the most stably expressed genes in all tissues, and thus are suitable as cross-tissue type normalization factors. However, we did not identify any universal reference genes post infection because the most stable genes varied between tissue types. Furthermore, for most tissues, the optimal reference genes identified by both algorithms at 12 h and 48 h post-infection differed. These results indicate that bacterial infection induced significant changes in the expression of abalone housekeeping genes in a manner that is dependent on tissue type and duration of infection. As a result, different normalization factors must be used for different tissues at different infection points.

Vibrio harveyi adheres to and penetrates tissues of the European abalone Haliotis tuberculata within the first hours of contact.

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Cardinaud, Marion; Barbou, Annaïck; Capitaine, Carole; Bidault, Adeline; Dujon, Antoine Marie; Moraga, Dario; Paillard, Christine

2014-10-01

Vibrio harveyi is a marine bacterial pathogen responsible for episodic epidemics generally associated with massive mortalities in many marine organisms, including the European abalone Haliotis tuberculata. The aim of this study was to identify the portal of entry and the dynamics of infection of V. harveyi in the European abalone. The results indicate that the duration of contact between V. harveyi and the European abalone influences the mortality rate and precocity. Immediately after contact, the epithelial and mucosal area situated between the gills and the hypobranchial gland was colonized by V. harveyi. Real-time PCR analyses and culture quantification of a green fluorescent protein-tagged strain of V. harveyi in abalone tissues revealed a high density of bacteria adhering to and then penetrating the whole gill-hypobranchial gland tissue after 1 h of contact. V. harveyi was also detected in the hemolymph of a significant number of European abalones after 3 h of contact. In conclusion, this article shows that a TaqMan real-time PCR assay is a powerful and useful technique for the detection of a marine pathogen such as V. harveyi in mollusk tissue and for the study of its infection dynamics. Thus, we have revealed that the adhesion and then the penetration of V. harveyi in European abalone organs begin in the first hours of contact. We also hypothesize that the portal of entry of V. harveyi in the European abalone is the area situated between the gills and the hypobranchial gland. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Influences of DMP on the fertilization process and subsequent embryogenesis of abalone (Haliotis diversicolor supertexta by gametes exposure.

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Jin Zhou

Full Text Available Di-methyl phthalate (DMP, a typical endocrine disrupting chemical (EDC, is ubiquitously distributed in aquatic environments; yet studies regarding its impact on gametes and the resulting effects on embryogenesis in marine gastropods are relatively scarce. In this study, the influences of DMP on the gametes and subsequent developmental process of abalone (Haliotis diversicolor supertexta, a representative marine benthic gastropod were assessed. Newborn abalone eggs and sperm were exposed separately to different DMP concentrations (1, 10 or 100 ppb for 60 min. At the end-point of exposure, the DMP-treated eggs and sperm were collected for analysis of their ultra-structures, ATPase activities and total lipid levels, and the fertilized gametes (embryos were collected to monitor related reproductive parameters (fertilization rate, abnormal development rate and hatching success rate. Treatment with DMP did not significantly alter the structure or total lipid content of eggs at any of the doses tested. Hatching failures and morphological abnormalities were only observed with the highest dose of DMP (100 ppb. However, DMP exposure did suppress sperm ATPase activities and affect the morphological character of their mitochondria. DMP-treated sperm exhibited dose-dependent decreases in fertilization efficiency, morphogenesis and hatchability. Relatively obvious toxicological effects were observed when both sperm and eggs were exposed to DMP. Furthermore, RT-PCR results indicate that treatment of gametes with DMP changed the expression patterns of physiologically-regulated genes (cyp3a, 17β-HSD-11 and 17β-HSD-12 in subsequent embryogenesis. Taken together, this study proofed that pre-fertilization exposure of abalone eggs, sperm or both to DMP adversely affects the fertilization process and subsequent embryogenesis.

Responses of primary cultured haemocytes from the marine gastropod Haliotis tuberculata under 10-day exposure to cadmium chloride

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Latire, Thomas; Le Pabic, Charles; Mottin, Elmina; Mottier, Antoine; Costil, Katherine; Koueta, Noussithe; Lebel, Jean-Marc [UMR 100 IFREMER ' Physiologie et Ecophysiologie des Mollusques Marins' - IFR 146 ICORE - IBFA - Universite de Caen Basse-Normandie, Campus 1, Science C, Esplanade de la Paix, 14032 Caen cedex (France); Serpentini, Antoine, E-mail: antoine.serpentini@unicaen.fr [UMR 100 IFREMER ' Physiologie et Ecophysiologie des Mollusques Marins' - IFR 146 ICORE - IBFA - Universite de Caen Basse-Normandie, Campus 1, Science C, Esplanade de la Paix, 14032 Caen cedex (France)

2012-03-15

Among metals, cadmium, a non-essential element, is an important pollutant that is released into aquatic environments. Due to its persistence and bioaccumulation, this metal has been shown to exert immunological effects on organisms. The objective of the present study was to investigate the in vitro effects of cadmium chloride using a haemocyte primary culture from the European abalone, Haliotis tuberculata. Most studies have maintained viable haemocytes in vitro for periods ranging from several hours to several days during acute exposures. Few investigations have reported the effects of metals using longer in vitro exposures, which are more realistic with regard to mimicking environmental conditions. In this study, we exposed abalone haemocytes to concentrations from 0.5 to 50,000 {mu}g L{sup -1} of CdCl{sub 2} for 10 days. The effects of cadmium chloride were reflected in a significant decrease in the number of viable cells and morphological modifications in a concentration-dependent manner beginning at a concentration of 500 {mu}g L{sup -1} as well as in some physiological processes, such as phagocytotic activity and the number of lysosome-positive cells. In contrast, phenoloxidase (PO) activity and reactive oxygen species (ROS) production were increased beginning at a concentration of 5 {mu}g L{sup -1}, which is consistent with environmental concentrations in polluted sites. For PO activity and ROS production, maximally 9-fold and 130% inductions, respectively, were recorded under the highest dose. These results thus indicate that cadmium chloride alters immune parameters of abalone haemocytes and that the long-term (10 days) primary culture system used here represents a suitable, sensitive in vitro model for assessing cytotoxic responses.

Responses of primary cultured haemocytes from the marine gastropod Haliotis tuberculata under 10-day exposure to cadmium chloride

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Latire, Thomas; Le Pabic, Charles; Mottin, Elmina; Mottier, Antoine; Costil, Katherine; Koueta, Noussithé; Lebel, Jean-Marc; Serpentini, Antoine

2012-01-01

Among metals, cadmium, a non-essential element, is an important pollutant that is released into aquatic environments. Due to its persistence and bioaccumulation, this metal has been shown to exert immunological effects on organisms. The objective of the present study was to investigate the in vitro effects of cadmium chloride using a haemocyte primary culture from the European abalone, Haliotis tuberculata. Most studies have maintained viable haemocytes in vitro for periods ranging from several hours to several days during acute exposures. Few investigations have reported the effects of metals using longer in vitro exposures, which are more realistic with regard to mimicking environmental conditions. In this study, we exposed abalone haemocytes to concentrations from 0.5 to 50,000 μg L −1 of CdCl 2 for 10 days. The effects of cadmium chloride were reflected in a significant decrease in the number of viable cells and morphological modifications in a concentration-dependent manner beginning at a concentration of 500 μg L −1 as well as in some physiological processes, such as phagocytotic activity and the number of lysosome-positive cells. In contrast, phenoloxidase (PO) activity and reactive oxygen species (ROS) production were increased beginning at a concentration of 5 μg L −1 , which is consistent with environmental concentrations in polluted sites. For PO activity and ROS production, maximally 9-fold and 130% inductions, respectively, were recorded under the highest dose. These results thus indicate that cadmium chloride alters immune parameters of abalone haemocytes and that the long-term (10 days) primary culture system used here represents a suitable, sensitive in vitro model for assessing cytotoxic responses.

Effect of antiaggregants on the in vitro viability, cell count and stability of abalone (Haliotis iris) haemocytes.

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Grandiosa, Roffi; Bouwman, Mai-Louise; Young, Tim; Mérien, Fabrice; Alfaro, Andrea C

2018-07-01

The ability to successfully prepare and preserve haemocyte cells for microscopy and flow cytometry is critical for the investigation of animal immune systems. In this study, we observed the total cell count, in vitro viability and stability of New Zealand black-footed abalone (Haliotis iris) haemocytes with different antiaggregants and handling protocols. Haemocyte stability was evaluated by direct observation of haemocytes under the microscope and calculating the aggregation index. Haemocyte counts and viability were measured via flow cytometry and tested for the effect of different antiaggregants (Alsever's solution at three concentrations, and specialised blood collection tubes containing lithium heparin and K 2 EDTA) at different temperatures and storage times. Results showed that Alsever's solution is an effective antiaggregant at haemolymph:antiaggregant dilution ratios of 1:1, 1:2 and 1:3. Lithium heparin was ineffective as an antiaggregant, whereas K 2 EDTA was similarly as effective as Alsever's solution. The influence of different mixing techniques (vortex, pipetting and flipping) were subsequently tested using the K 2 EDTA Microtainer ® tubes, revealing that proper mixing should be performed immediately. High cell viability can be achieved by mixing samples by either 10 s of vortexing (1000 rpm), 10 times pipetting or 20 times flipping. The in vitro storage of abalone haemocytes in AS and K 2 EDTA as antiaggregants at ambient room temperature was highly effective for up to 24 h (75-85% viability; 0.05-0.15 aggregation index) and is recommended for haemocyte studies in H. iris. Utilization of K 2 EDTA Microtainer ® tubes were advantageous since they are more cost effective compared to Alsever's solution, and samples can be prepared more efficiently. Copyright © 2018. Published by Elsevier Ltd.

Uptake, distribution and depuration of paralytic shellfish toxins from Alexandrium minutum in Australian greenlip abalone, Haliotis laevigata.

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Dowsett, Natalie; Hallegraeff, Gustaaf; van Ruth, Paul; van Ginkel, Roel; McNabb, Paul; Hay, Brenda; O'Connor, Wayne; Kiermeier, Andreas; Deveney, Marty; McLeod, Catherine

2011-07-01

Farmed greenlip abalone Haliotis laevigata were fed commercial seaweed-based food pellets or feed pellets supplemented with 8 × 10⁵ Alexandrium minutum dinoflagellate cells g⁻¹ (containing 12 ± 3.0 μg STX-equivalent 100 g⁻¹, which was mainly GTX-1,4) every second day for 50 days. Exposure of abalone to PST supplemented feed for 50 days did not affect behaviour or survival but saw accumulation of up to 1.6 μg STX-equivalent 100 g⁻¹ in the abalone foot tissue (muscle, mouth without oesophagus and epipodial fringe), which is ∼50 times lower than the maximum permissible limit (80 μg 100 g⁻¹ tissue) for PSTs in molluscan shellfish. The PST levels in the foot were reduced to 0.48 μg STX-equivalent 100 g⁻¹ after scrubbing and removal of the pigment surrounding the epithelium of the epipodial fringe (confirmed by both HPLC and LC-MS/MS). Thus, scrubbing the epipodial fringe, a common procedure during commercial abalone canning, reduced PST levels by ∼70%. Only trace levels of PSTs were detected in the viscera (stomach, gut, heart, gonad, gills and mantle) of the abalone. A toxin reduction of approximately 73% was observed in STX-contaminated abalone held in clean water and fed uncontaminated food over 50 days. The low level of PST uptake when abalone were exposed to high numbers of A. minutum cells over a prolonged period may indicate a low risk of PSP poisoning to humans from the consumption of H. laevigata that has been exposed to a bloom of potentially toxic A. minutum in Australia. Further research is required to establish if non-dietary accumulation can result in significant levels of PSTs in abalone. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Exploring Spatiotemporal Trends in Commercial Fishing Effort of an Abalone Fishing Zone: A GIS-Based Hotspot Model

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Jalali, M. Ali; Ierodiaconou, Daniel; Gorfine, Harry; Monk, Jacquomo; Rattray, Alex

2015-01-01

Assessing patterns of fisheries activity at a scale related to resource exploitation has received particular attention in recent times. However, acquiring data about the distribution and spatiotemporal allocation of catch and fishing effort in small scale benthic fisheries remains challenging. Here, we used GIS-based spatio-statistical models to investigate the footprint of commercial diving events on blacklip abalone (Haliotis rubra) stocks along the south-west coast of Victoria, Australia from 2008 to 2011. Using abalone catch data matched with GPS location we found catch per unit of fishing effort (CPUE) was not uniformly spatially and temporally distributed across the study area. Spatial autocorrelation and hotspot analysis revealed significant spatiotemporal clusters of CPUE (with distance thresholds of 100’s of meters) among years, indicating the presence of CPUE hotspots focused on specific reefs. Cumulative hotspot maps indicated that certain reef complexes were consistently targeted across years but with varying intensity, however often a relatively small proportion of the full reef extent was targeted. Integrating CPUE with remotely-sensed light detection and ranging (LiDAR) derived bathymetry data using generalized additive mixed model corroborated that fishing pressure primarily coincided with shallow, rugose and complex components of reef structures. This study demonstrates that a geospatial approach is efficient in detecting patterns and trends in commercial fishing effort and its association with seafloor characteristics. PMID:25992800

Exploring Spatiotemporal Trends in Commercial Fishing Effort of an Abalone Fishing Zone: A GIS-Based Hotspot Model.

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M Ali Jalali

Full Text Available Assessing patterns of fisheries activity at a scale related to resource exploitation has received particular attention in recent times. However, acquiring data about the distribution and spatiotemporal allocation of catch and fishing effort in small scale benthic fisheries remains challenging. Here, we used GIS-based spatio-statistical models to investigate the footprint of commercial diving events on blacklip abalone (Haliotis rubra stocks along the south-west coast of Victoria, Australia from 2008 to 2011. Using abalone catch data matched with GPS location we found catch per unit of fishing effort (CPUE was not uniformly spatially and temporally distributed across the study area. Spatial autocorrelation and hotspot analysis revealed significant spatiotemporal clusters of CPUE (with distance thresholds of 100's of meters among years, indicating the presence of CPUE hotspots focused on specific reefs. Cumulative hotspot maps indicated that certain reef complexes were consistently targeted across years but with varying intensity, however often a relatively small proportion of the full reef extent was targeted. Integrating CPUE with remotely-sensed light detection and ranging (LiDAR derived bathymetry data using generalized additive mixed model corroborated that fishing pressure primarily coincided with shallow, rugose and complex components of reef structures. This study demonstrates that a geospatial approach is efficient in detecting patterns and trends in commercial fishing effort and its association with seafloor characteristics.

Effects of a range-expanding sea urchin on behaviour of commercially fished abalone.

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Strain, Elisabeth M A; Johnson, Craig R; Thomson, Russell J

2013-01-01

Global climate change has resulted in a southerly range expansion of the habitat modifying sea urchin Centrostephanus rodgersii to the east coast of Tasmania, Australia. Various studies have suggested that this urchin outcompetes black-lipped abalone (Haliotis rubra) for resources, but experiments elucidating the mechanisms are lacking. We outline a new framework involving experimental manipulations and Markov chain and Pareto modelling to examine the effects of interspecific competition between urchins and abalone and the effect of intraspecific competition in abalone, assessed as effects on behaviour. Manipulations of abalone densities had no detectable effect on urchin behavioural transitions, movement patterns or resightability through time. In contrast, additions of urchins resulted in abalone shifting microhabitats from exposed to sheltered positions, an increase in the proportion of mobile abalone, and declines in abalone resightability through time relative to controls without the urchins. Our results support the hypothesis of asymmetrical competitive interactions between urchins and abalone. The introduction of urchins to intact algal beds causes abalone to flee and seek shelter in cryptic microhabitat which will negatively impact both their accessibility to such microhabitats, and productivity of the abalone fishery, and will potentially affect their growth and survival, while the presence of the abalone has no detectable effect on the urchin. Our approach involving field-based experiments and modelling could be used to test the effects of other invasive species on native species behaviour.

Abalone Hemocyanin Blocks the Entry of Herpes Simplex Virus 1 into Cells: a Potential New Antiviral Strategy

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Talaei Zanjani, Negar; Miranda-Saksena, Monica; Valtchev, Peter; Hueston, Linda; Diefenbach, Eve; Sairi, Fareed; Gomes, Vincent G.

2015-01-01

A marine-derived compound, abalone hemocyanin, from Haliotis rubra was shown to have a unique mechanism of antiviral activity against herpes simplex virus 1 (HSV-1) infections. In vitro assays demonstrated the dose-dependent and inhibitory effect of purified hemocyanin against HSV-1 infection in Vero cells with a 50% effective dose (ED50) of 40 to 50 nM and no significant toxicity. In addition, hemocyanin specifically inhibited viral attachment and entry by binding selectively to the viral surface glycoproteins gD, gB, and gC, probably by mimicking their receptors. However, hemocyanin had no effect on postentry events and did not block infection by binding to cellular receptors for HSV. By the use of different mutants of gD and gB and a competitive heparin binding assay, both protein charge and conformation were shown to be the driving forces of the interaction between hemocyanin and viral glycoproteins. These findings also suggested that hemocyanin may have different motifs for binding to each of the viral glycoproteins B and D. The dimer subunit of hemocyanin with a 10-fold-smaller molecular mass exhibited similar binding to viral surface glycoproteins, showing that the observed inhibition did not require the entire multimer. Therefore, a small hemocyanin analogue could serve as a new antiviral candidate for HSV infections. PMID:26643336

Identification of differentially expressed reproductive and metabolic proteins in the female abalone (Haliotis laevigata) gonad following artificial induction of spawning.

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Mendoza-Porras, Omar; Botwright, Natasha A; Reverter, Antonio; Cook, Mathew T; Harris, James O; Wijffels, Gene; Colgrave, Michelle L

2017-12-01

Inefficient control of temperate abalone spawning prevents pair-wise breeding and production of abalone with highly marketable traits. Traditionally, abalone farmers have used a combination of UV irradiation and application of temperature gradients to the tank water to artificially induce spawning. Proteins are known to regulate crucial processes such as respiration, muscle contraction, feeding, growth and reproduction. Spawning as a pre-requisite of abalone reproduction is likely to be regulated, in part, by endogenous proteins. A first step in elucidating the mechanisms that regulate spawning is to identify which proteins are directly involved during spawning. The present study examined protein expression following traditional spawning induction in the Haliotis laevigata female. Gonads were collected from abalone in the following physiological states: (1) spawning; (2) post-spawning; and (3) failed-to-spawn. Differential protein abundance was initially assessed using two-dimensional difference in-gel electrophoresis coupled with mass spectrometry for protein identification. A number of reproductive proteins such as vitellogenin, vitelline envelope zona pellucida domain 29 and prohibitin, and metabolic proteins such as thioredoxin peroxidase, superoxide dismutase and heat shock proteins were identified. Differences in protein abundance levels between physiological states were further assessed using scheduled multiple reaction monitoring mass spectrometry. Positive associations were observed between the abundance of specific proteins, such as heat shock cognate 70 and peroxiredoxin 6, and the propensity or failure to spawn in abalone. These findings have contributed to better understand both the effects of oxidative and heat stress over abalone physiology and their influence on abalone spawning. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Dietary effects of marine food intake on intestinal and hepatic enzyme activities in rats.

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González, M; Caride, B; Lamas, A; Taboada, C

2001-03-01

Dietary effects of two diets high in protein from two marine species (Haliotis tuberculata and Anemonia viridis) as compared to a high-quality patron protein such as casein (or casein supplemented with olive oil) on intestinal and hepatic enzymes were studied. After 23 days, the two marine species as diet compared to casein increased the disaccharidase and alkaline phosphatase activities. Feeding Haliotis tuberculata meal produced a decrease on intestinal leucine aminopeptidase activity. The hepatic gamma-glutamyltranspeptidase activity decreased slightly in animals fed Haliotis tuberculata meal. Supplementation of casein with olive oil tended to decrease the intestinal and hepatic enzyme activity.

Involvement of clip-domain serine protease in the anti-Vibrio immune response of abalone (Haliotis discus hannai)-Molecular cloning, characterization and functional analysis.

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Hu, Jian-Jian; Chen, Yu-Lei; Duan, Xue-Kun; Jin, Teng-Chuan; Li, Yue; Zhang, Ling-Jing; Liu, Guang-Ming; Cao, Min-Jie

2018-01-01

Vibrio parahemolyticus (V. parahemolyticus) is a major pathogen for abalone, an important economical shellfish in coastal area of China. There is little known about the abalone innate immune system against pathogen infection. Clip-domain serine proteases (cSPs) are increasingly recognized to play important roles in host immune defense in invertebrates. In this study, we cloned a cSP (Hdh-cSP) from abalone (Haliotis discus hannai). We found out that Hdh-cSP was widely expressed in multiple tissues of abalone, with highest level in the immune-like organ, hepatopancreas. V. parahemolyticus infection induced significantly elevated expression of Hdh-cSP in addition to better-characterized innate immune component genes including Rel/NF-κB, allograft inflammatory factor (ALInFa), macrophage expressed protein (MEP) and caspase-8. Importantly, the silencing of Hdh-cSP reduced the expression of these genes, suggesting that Hdh-cSP was an upstream regulatory factor in V. parahemolyticus infection. Further analysis showed that apoptosis of hemocytes was inhibited when the transcription of Hdh-cSP was knocked down, suggesting that Hdh-cSP participated in cell apoptosis by regulation of caspase 8 expression in V. parahemolyticus infection. Therefore, our study established an important role of cSP in the innate immunity against V. parahemolyticus infection in abalone. Copyright © 2017 Elsevier Ltd. All rights reserved.

The immune response of Taiwan abalone Haliotis diversicolor supertexta and its susceptibility to Vibrio parahaemolyticus at different salinity levels.

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Cheng, Winton; Juang, Feng-Ming; Chen, Jiann-Chu

2004-03-01

Addition of NaCl at 2.5% to 3.5% to tryptic soy broth (TSB) significantly increased the growth of Vibrio parahaemolyticus. Taiwan abalone Haliotis diversicolor supertexta held in 30 per thousand seawater were injected with V. parahaemolyticus grown in TSB containing NaCl at 0.5, 1.5, 2.5, 3.5 and 4.5% at a dose of 1.6 x 10(5)colony-forming units (cfu) abalone(-1). After 48 h, the cumulative mortality was significantly higher for the abalone challenged with V. parahaemolyticus grown in 2.5% than those grown in 0.5 and 1.5% NaCl. In other experiments, abalones held in 30 per thousand seawater were injected with TSB-grown V. parahaemolyticus (1.6 x 10(5)cfu abalone(-1)), and then transferred to 20, 25, 30 and 35 per thousand seawater. All abalones held in 20 per thousand were killed in 48 h. The mortality of V. parahaemolyticus-injected abalone held in 30 per thousand was significantly lower over 24-120 h. Abalone held in 30 per thousand seawater and then transferred to 20, 25, 30 and 35 per thousand were examined for THC (total haemocyte count), phenoloxidase activity, respiratory burst, phagocytic activity and clearance efficiency of V. parahemolyticus after 24 and 72 h. The THC increased directly related with salinity levels. Phenoloxidase activity, respiratory burst, phagocytic activity and clearance efficiency of V. parahaemolyticus decreased significantly for the abalone in 20, 25 and 35 per thousand. It is concluded that the abalone transferred from 30 per thousand to 20, 25 and 35 per thousand had reduced immune ability and decreased resistance against V. parahaemolyticus infection.

Cytogenetic analysis and chromosomal characteristics of the polymorphic 18S rDNA of Haliotis discus hannai from Fujian, China.

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Haishan Wang

Full Text Available We report on novel chromosomal characteristics of Haliotis discus hannai from a breeding population at Fujian, China. The karyotypes of H. discus hannai we obtained from an abalone farm include a common type 2n = 36 = 10M + 8SM (82% and two rare types 2n = 36 = 11M + 7SM (14% and 2n = 36 = 10M + 7SM + 1ST (4%. The results of silver staining showed that the NORs of H. discus hannai were usually located terminally on the long arms of chromosome pairs 14 and 17, NORs were also sometimes located terminally on the short arms of other chromosomes, either metacentric or submetacentric pairs. The number of Ag-nucleoli ranged from 2 to 8, and the mean number was 3.61 ± 0.93. Among the scored interphase cells, 41% had 3 detectable nucleoli and 37% had 4 nucleoli. The 18S rDNA FISH result is the first report of the location of 18S rDNA genes in H. discus hannai. The 18S rDNA locations were highly polymorphic in this species. Copies of the gene were observed in the terminal of long or/and short arms of submetacentric or/and metacentric chromosomes. Using FISH with probe for vertebrate-like telomeric sequences (CCCTAA3 displayed positive green FITC signals at telomere regions of all analyzed chromosome types. We found about 7% of chromosomes had breaks in prophase. A special form of nucleolus not previously described from H. discus hannai was observed in some interphase cells. It consists of many small silver-stained nucleoli gathered together to form a larger nucleolus and may correspond to prenucleolar bodies.

Beta-1,3-1,6-glucan modulate the non-specific immune response to enhance the survival in the Vibrio alginolyticus infection of Taiwan abalone (Haliotis diversicolor supertexta).

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Wu, Yu-Sheng; Tseng, Tzu-Yu; Nan, Fan-Hua

2016-07-01

This research aims to investigate the non-specific immune response of Taiwan abalone (Haliotis diversicolor supertexta) which was treated with the beta-1,3-1,6-glucan to be observed in the survival impact after the Vibrio alginolyticus infection. The non-specific immune and physiological response of superoxide anion radical (O2(-)), phenoloxidase (PO), phagocytic index (PI), phagocytic rate (PR) and lucigenin-chemiluminescence for reactive oxygen intermediates (ROIs) were enhanced via in-vitro experiment. In the in-vivo experiment, the observed data presented that the haemolymph lysate supernatant (HLS), superoxide dismutase (SOD), glutamate oxalacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) were not significant enhanced, but the total haemocyte count (THC), O2(-), PO, phagocytic index (PI), phagocytic ratio (PR) and other parameters of immune were significantly promoted after treated with beta-1,3-1,6-glucan. In the challenge experiment, the survival rates of abalone in the 40 and 80 μl/ml groups of beta-1,3-1,6-glucan were observed from 6.67% up to 33.33% and 36.67% after injection with Vibrio alginolyticus, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kazal-type proteinase inhibitor from disk abalone (Haliotis discus discus): molecular characterization and transcriptional response upon immune stimulation.

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Wickramaarachchi, W D Niroshana; De Zoysa, Mahanama; Whang, Ilson; Wan, Qiang; Lee, Jehee

2013-09-01

Proteinases and proteinase inhibitors are involved in several biological and physiological processes in all multicellular organisms. Proteinase inhibitors play a key role in regulating the activity of the respective proteinases. Among serine proteinase inhibitors, kazal-type proteinase inhibitors (KPIs) are widely found in mammals, avians, and a variety of invertebrates. In this study, we describe the identification of a kazal-type serine proteinase inhibitor (Ab-KPI) from the disk abalone, Haliotis discus discus, which is presumably involved in innate immunity. The full-length cDNA of Ab-KPI includes 600 bp nucleotides with an open reading frame (ORF) encoding a polypeptide of 143 amino acids. The deduced amino acid sequence of Ab-KPI contains a putative 17-amino acid signal peptide and two tandem kazal domains with high similarity to other kazal-type SPIs. Each kazal domain consists of reactive site (P1) residue containing a leucine (L), and a threonine (T) located in the second amino acid position after the second conserved cysteine of each domain. Temporal expression of Ab-KPI was assessed by real time quantitative PCR in hemocytes and mantle tissue following bacterial and viral hemorrhagic septicemia virus (VHSV) challenge, and tissue injury. At 6 h post-bacterial and -VHSV challenge, Ab-KPI expression in hemocytes was increased 14-fold and 4-fold, respectively, compared to control samples. The highest up-regulations upon tissue injury were shown at 9 h and 12 h in hemocytes and mantle, respectively. The transcriptional modulation of Ab-KPI following bacterial and viral challenges and tissue injury indicates that it might be involved in immune defense as well as wound healing process in abalone. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of dietary lipid on the growth, fatty acid composition and Δ5 Fads expression of abalone ( Haliotis discus hannai Ino) hepatopancreas

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Li, Mingzhu; Mai, Kangsen; Ai, Qinghui; He, Gen; Xu, Wei; Zhang, Wenbing; Zhang, Yanjiao; Zhou, Huihui; Liufu, Zhiguo

2015-04-01

This study investigated the effect of dietary lipid on the growth, fatty acid composition and Δ5 fatty acyl desaturase genes ( Fads) expression of juvenile abalone ( Haliotis discus hannai Ino) hepatopancreas. Six purified diets were formulated to contain tripalmitin (TP), olive oil (OO, 72.87% 18:1n-9), grape seed oil (GO, 68.67% 18:2n-6), linseed oil (LO, 70.48% 18:3n-3), ARA oil (AO, 41.81% ARA) or EPA oil (EO, 44.09% EPA and 23.67% DAH). No significant difference in survival rate was observed among abalone fed with different diets. Weight gain rate ( WGR) and daily growth rate of shell length ( DGR SL) were significantly increased in abalone fed with diets containing OO, AO and EO, but decreased in abalone fed with LO diet ( P abalone fed with GO than those fed with TP, OO, LO and EO ( P abalone fed with LO was significantly higher than those in abalone fed with TP, OO, GO and AO ( P abalone fed with OO. The expression of Δ5 Fads in hepatopancreas of abalone was enhanced by high concentration of 18:3n-3 and suppressed by dietary LC-PUFAs; however it was not affected by dietary high concentration of 18:1n-9 or 18:2n-6. These results provided valuable information for understanding the synthesis of LC-PUFAs and nutritional regulation of Δ5 Fads expression in abalone.

AKTIVITAS ENZIM KOMERSIAL, EKSTRAK KASAR ENZIM DARI VISCERA KEONG MAS (Pila polita, ABALON (Haliotis asinina, DAN BEKICOT (Achatina fulica UNTUK LISIS JARINGAN RUMPUT LAUT Kappaphycus alvarezii PADA KULTUR PROTOPLAS

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Sri Redjeki Hesti Mulyaningrum

2008-12-01

Full Text Available Dalam usaha perbaikan kualitas bibit rumput laut Kappaphycus alvarezii dilakukan kultur protoplas dengan isolasi protoplas menggunakan enzim. Untuk mendapatkan sumber enzim yang ekonomis sebagai alternatif pengganti enzim komersial dan untuk mengetahui perbandingan konsentrasi enzim komersial yang optimum agar menghasilkan jumlah protoplas yang maksimum, dilakukan karakterisasi terhadap enzim dari berbagai sumber. Aktivitas ekstrak kasar enzim dari viscera bekicot (Achatina fulica tidak berbeda nyata dengan enzim komersial (P>0,05 dengan aktivitas sebesar 0,729 unit/mL; enzim komersial 0,354 unit/mL; ekstrak kasar enzim dari viscera keong mas (Pila polita 0,048 unit/mL; dan ekstrak kasar enzim dari viscera abalon (Haliotis asinina 0,014 unit/mL. Perbandingan enzim komersial yang optimum adalah 2:1 menghasilkan protoplas sebanyak 1,26 x 108 sel/mL; kemudian 1:2 dengan jumlah protoplas 1,22 x 108 sel/mL; perbandingan 1:1 menghasilkan protoplas sebanyak 8,36 x 107 sel/mL; perbandingan 0:1 menghasilkan protoplas sebanyak 6,33 x 107 sel/mL; dan perbandingan 1:0 menghasilkan protoplas sebanyak 9,55 x 106 sel/mL. Rumput laut asal Takalar memiliki protoplas dengan kepadatan tertinggi sebesar 3,7 x 108 sel/mL. Effort to improve the quality of seaweed seed Kappaphycus alvarezii has been done by protoplast culture with protoplast isolation using enzyme. To find out economical enzyme sources as alternatives to substitute the expensive commercial enzyme and to determine the optimum concentration ratio of commercial enzyme to produce maximum amount of protoplast, characterization was executed to several potential sources. Activity of crude extract enzyme from viscera of garden snail (Achatina fulica was not significantly different with commercial enzyme (P>0.05 it was 0.729 unit/mL, commercial enzyme 0.354 unit/mL activity; crude extract enzyme from viscera of golden snail (Pila polita 0.048 unit/mL activity and crude extract enzyme from viscera of abalone

Характеристика водного обмена листьев Quercus robur L. и Quercus rubra L. в чистых и смешанных группах

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Анастасия КРИВОРУЧКО

2017-06-01

Full Text Available The peculiarities of water metabolism of the leaves of English oak (Quercus robur L. and red oak (Quercus rubra L. in pure and mixed groups were examined. Twelve-year-old forest plantations of both species on an area of 1.6 ha were the object of study. It was found that in both pure and mixed groups the leaves of Q. robur are characterized by more intense transpiration than Q. rubra. The joint growth of these species, on the whole, leads to a more active evaporation of water by Q. robur leaves than in the single-species groups. The leaves of Q. rubra in two-species groups lose less or the same amount of water in the transpiration process as in the single-species groups. The leaves of Q. rubra having a higher water storage capacity in both variants are characterized by a more uniform and stable daily course of transpiration. As a result of the joint growth, the water deficit in the leaves of Q. rubra increased in July and September compared to the pure groups. The differences in the leaves of Q. robur between the two studied sites are unreliable. The obtained data indicate the absence of an explicit negative mutual influence between the species on the water metabolism indices of their leaves. Реферат. Изучены особенности водного обмена листьев дуба обыкновенного (Quercus robur L. и дуба красного (Quercus rubra L. в чистых и смешанных группах. Объектами исследования были 12-летние лесные культуры обоих видов, площадью 1,6 га. Установлено, что как в чистых, так и в смешанных группах листья Q. robur характеризуются более интенсивной транспирацией в сравнении с Q. rubra. Совместный рост этих видов приводит, в целом, к более �

Anti-allergic effects of a nonameric peptide isolated from the intestine gastrointestinal digests of abalone (Haliotis discus hannai) in activated HMC-1 human mast cells.

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Ko, Seok-Chun; Lee, Dae-Sung; Park, Won Sun; Yoo, Jong Su; Yim, Mi-Jin; Qian, Zhong-Ji; Lee, Chang-Min; Oh, Junghwan; Jung, Won-Kyo; Choi, Il-Whan

2016-01-01

The aim of the present study was to examine whether the intestine gastrointestinal (GI) digests of abalone [Haliotis discus hannai (H. discus hannai)] modulate inflammatory responses and to elucidate the mechanisms involved. The GI digests of the abalone intestines were fractionated into fractions I (>10 kDa), II (5-10 kDa) and Ⅲ (abalone intestine GI digests (AIGIDs), fraction Ⅲ inhibited the passive cutaneous anaphylaxis (PCA) reaction in mice. Subsequently, a bioactive peptide [abalone intestine GI digest peptide (AIGIDP)] isolated from fraction Ⅲ was determined to be 1175.2 Da, and the amino acid sequence was found to be PFNQGTFAS. We noted that the purified nonameric peptide (AIGIDP) attenuated the phorbol‑12‑myristate 13-acetate plus calcium ionophore A23187 (PMACI)-induced histamine release and the production of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in human mast cells (HMC-1 cells). In addition, we also noted that AIGIDP inhibited the PMACI‑induced activation of nuclear factor‑κB (NF-κB) by suppressing IκBα phosphorylation and that it suppressed the production of cytokines by decreasing the phosphorylation of JNK. The findings of our study indicate that AIGIDP exerts a modulatory, anti-allergic effect on mast cell-mediated inflammatory diseases.

Stabilization of metals in acidic mine spoil with amendments and red fescue (Festuca rubra L.) growth.

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Simon, László

2005-12-01

Stabilization of metals with amendments and red fescue (Festuca rubra, cv. Keszthelyi 2) growth was studied on an acidic and phytotoxic mine spoil (pH(KCl) 3.20-3.26; Cd 7.1 mg kg(-1), Cu 120 mg kg(-1), Pb 2154 mg kg(-1) and Zn 605 mg kg(-1)) from Gyöngyösoroszi, Hungary in a pot experiment. Raising the pH above 5.0 by lime (CaCO(3)), and supplementing with 40 mg kg(-1)nitrogen (NH(4)NO(3)) made this material suitable for plant growth. All cultures were limed with 0.5% (m/m) CaCO(3) (treatment 1), which was combined with 5% (m/m) municipal sewage sludge compost (treatment 2), 5% (m/m) peat (treatment 3), 7.5% (m/m) natural zeolite (clinoptilolite) (treatment 4), and 0.5 (m/m) KH(2)PO(4) (treatment 5). Treatments 1-5 were combined with each other (treatment 6). After 60 days of red fescue growth, pH of the limed mine spoil decreased in all cultures units. Application of peat caused the highest pH decrease (1.15), while decrease of pH was less than 0.23 in treatments 2, 5 or 6. Application of lime significantly reduced concentrations of metals in the 'plant available' fraction of mine spoil compared to non-limed mine spoil. Amendments added to limed mine spoil changed variously the ratio of Cd, Cu, Pb and Zn in exchangeable or 'plant available' fractions, differently influencing the phytoavailability of these metals. Most of the metals were captured in the roots of test plants. Treatment 2 caused the appearance of less Cd in shoots (spoil, however the application of 0.5 phosphate was less favourable. Liming, application of amendments and growth of red fescue can stabilize metals in acidic and phytotoxic mine spoil, and by phytostabilization they can reduce the risk of metal contamination of the food chain.

Effects of a range-expanding sea urchin on behaviour of commercially fished abalone.

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Elisabeth M A Strain

Full Text Available Global climate change has resulted in a southerly range expansion of the habitat modifying sea urchin Centrostephanus rodgersii to the east coast of Tasmania, Australia. Various studies have suggested that this urchin outcompetes black-lipped abalone (Haliotis rubra for resources, but experiments elucidating the mechanisms are lacking.We outline a new framework involving experimental manipulations and Markov chain and Pareto modelling to examine the effects of interspecific competition between urchins and abalone and the effect of intraspecific competition in abalone, assessed as effects on behaviour. Manipulations of abalone densities had no detectable effect on urchin behavioural transitions, movement patterns or resightability through time. In contrast, additions of urchins resulted in abalone shifting microhabitats from exposed to sheltered positions, an increase in the proportion of mobile abalone, and declines in abalone resightability through time relative to controls without the urchins. Our results support the hypothesis of asymmetrical competitive interactions between urchins and abalone.The introduction of urchins to intact algal beds causes abalone to flee and seek shelter in cryptic microhabitat which will negatively impact both their accessibility to such microhabitats, and productivity of the abalone fishery, and will potentially affect their growth and survival, while the presence of the abalone has no detectable effect on the urchin. Our approach involving field-based experiments and modelling could be used to test the effects of other invasive species on native species behaviour.

Antibacterial activity and immune responses of a molluscan macrophage expressed gene-1 from disk abalone, Haliotis discus discus.

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Bathige, S D N K; Umasuthan, Navaneethaiyer; Whang, Ilson; Lim, Bong-Soo; Won, Seung Hwan; Lee, Jehee

2014-08-01

The membrane-attack complex/perforin (MACPF) domain-containing proteins play an important role in the innate immune response against invading microbial pathogens. In the current study, a member of the MACPF domain-containing proteins, macrophage expressed gene-1 (MPEG1) encoding 730 amino acids with the theoretical molecular mass of 79.6 kDa and an isoelectric point (pI) of 6.49 was characterized from disk abalone Haliotis discus discus (AbMPEG1). We found that the characteristic MACPF domain (Val(131)-Tyr(348)) and transmembrane segment (Ala(669)-Ile(691)) of AbMPEG1 are located in the N- and C-terminal ends of the protein, respectively. Ortholog comparison revealed that AbMPEG1 has the highest sequence identity with its pink abalone counterpart, while sequences identities of greater than 90% were observed with MPEG1 members from other abalone species. Likewise, the furin cleavage site KRRRK was highly conserved in all abalone species, but not in other species investigated. We identified an intron-less genomic sequence within disk abalone AbMPEG1, which was similar to other mammalian, avian, and reptilian counterparts. Transcription factor binding sites, which are important for immune responses, were identified in the 5'-flanking region of AbMPEG1. qPCR revealed AbMPEG1 transcripts are present in every tissues examined, with the highest expression level occurring in mantle tissue. Significant up-regulation of AbMPEG1 transcript levels was observed in hemocytes and gill tissues following challenges with pathogens (Vibrio parahemolyticus, Listeria monocytogenes and viral hemorrhagic septicemia virus) as well as pathogen-associated molecular patterns (PAMPs: lipopolysaccharides and poly I:C immunostimulant). Finally, the antibacterial activity of the MACPF domain was characterized against Gram-negative and -positive bacteria using a recombinant peptide. Taken together, these results indicate that the biological significance of the AbMPEG1 gene includes a role in

Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens

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Brokordt, Katherina B.; González, Roxana C.; Farías, William J.; Winkler, Federico M.

2015-01-01

Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs) are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h 2) and the additive genetic coefficient of variation (CV A) of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes) and extracellular (serum) protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R), the h 2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h 2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CV A of 13.3–16.2% in young adults and of 2.7–8.1% in pre-harvest adults. Thus, despite its low h 2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals. PMID

Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens.

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Katherina B Brokordt

Full Text Available Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h2 and the additive genetic coefficient of variation (CVA of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes and extracellular (serum protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R, the h2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CVA of 13.3-16.2% in young adults and of 2.7-8.1% in pre-harvest adults. Thus, despite its low h2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals.

Structural and functional characterization of a novel molluskan ortholog of TRAF and TNF receptor-associated protein from disk abalone (Haliotis discus discus).

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Lee, Youngdeuk; Elvitigala, Don Anushka Sandaruwan; Whang, Ilson; Lee, Sukkyoung; Kim, Hyowon; Zoysa, Mahanama De; Oh, Chulhong; Kang, Do-Hyung; Lee, Jehee

2014-09-01

Immune signaling cascades have an indispensable role in the host defense of almost all the organisms. Tumor necrosis factor (TNF) signaling is considered as a prominent signaling pathway in vertebrate as well as invertebrate species. Within the signaling cascade, TNF receptor-associated factor (TRAF) and TNF receptor-associated protein (TTRAP) has been shown to have a crucial role in the modulation of immune signaling in animals. Here, we attempted to characterize a novel molluskan ortholog of TTRAP (AbTTRAP) from disk abalone (Haliotis discus discus) and analyzed its expression levels under pathogenic stress. The complete coding sequence of AbTTRAP consisted of 1071 nucleotides, coding for a 357 amino acid peptide, with a predicted molecular mass of 40 kDa. According to our in-silico analysis, AbTTRAP resembled the typical TTRAP domain architecture, including a 5'-tyrosyl DNA phosphodiesterase domain. Moreover, phylogenetic analysis revealed its common ancestral invertebrate origin, where AbTTRAP was clustered with molluskan counterparts. Quantitative real time PCR showed universally distributed expression of AbTTRAP in selected tissues of abalone, from which more prominent expression was detected in hemocytes. Upon stimulation with two pathogen-derived mitogens, lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (poly I:C), transcript levels of AbTTRAP in hemocytes and gill tissues were differentially modulated with time. In addition, the recombinant protein of AbTTRAP exhibited prominent endonuclease activity against abalone genomic DNA, which was enhanced by the presence of Mg(2+) in the medium. Collectively, these results reinforce the existence of the TNF signaling cascade in mollusks like disk abalone, further implicating the putative regulatory behavior of TTRAP in invertebrate host pathology. Copyright © 2014 Elsevier Ltd. All rights reserved.

Use of ionizing radiation in grass breeding. I

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Indruch, I.; Svetlik, V.; Ligocki, J.

1980-01-01

Two subspecies of F. rubra occurring in natural localities of north-east Moravia (CSSR) in the Beskydy Mts. were used. In Festuca rubra L. ssp. genuina grandiflora (Hack.) 2n=8x=56, F. rubra represented a model species used for testing the effects of both acute and chronic gamma irradiation. In Festuca rubra L. ssp. vulgaris (Gaud.) Hay 2n=6x=42, new breeding was realized with success. The effects on important features of grasses were identical in both cases. The extension of combining abilities is especially important because it allows the production of forms less frequent in natural populations. (author)

The Effect of Pleistocene Climate Fluctuations on Distribution of European Abalone (Haliotis tuberculata), Revealed by Combined Mitochondrial and Nuclear Marker Analyses.

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Roussel, Valérie; Van Wormhoudt, Alain

2017-04-01

The genetic differentiation among the populations of the European abalone Haliotis tuberculata was investigated using different markers to better understand the evolutionary history and exchanges between populations. Three markers were used: mitochondrial cytochrome oxidase I (COI), the sperm lysin nuclear gene, and eight nuclear microsatellites. These markers present different characteristics concerning mutation rate and inheritance, which provided complementary information about abalone history and gene diversity. Genetic diversity and relationships among subspecies were calculated from a sample of approximately 500 individuals, collected from 17 different locations in the north-eastern Atlantic Ocean, Macaronesia, and Mediterranean Sea. COI marker was used to explore the phylogeny of the species with a network analysis and two phylogenetic methods. The analysis revealed 18 major haplotypes grouped into two distinct clades with a pairwise sequence divergence up to 3.5 %. These clades do not correspond to subspecies but revealed many contacts along Atlantic coast during the Pleistocene interglaciations. The sperm lysin gene analysis separated two different subtaxa: one associated to Macaronesian islands, and the other to all other populations. Moreover, a small population of the northern subtaxon was isolated in the Adriatic Sea-probably before the separation of the two lineages-and evolved independently. Microsatellites were analyzed by different genetics methods, including the Bayesian clustering method and migration patterns analysis. It revealed genetically distinct microsatellite patterns among populations from Mediterranean Sea, Brittany and Normandy, Morocco, and Canary and Balearic islands. Gene flow is asymmetric among the regions; the Azores and the Canary Islands are particularly isolated and have low effective population sizes. Our results support the hypothesis that climate changes since the Pleistocene glaciations have played a major role in the

Evaluation of reference genes for RT-qPCR study in abalone Haliotis discus hannai during heavy metal overload stress

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Sang Yoon Lee

2016-06-01

Full Text Available Abstract Background The evaluation of suitable reference genes as normalization controls is a prerequisite requirement for launching quantitative reverse transcription-PCR (RT-qPCR-based expression study. In order to select the stable reference genes in abalone Haliotis discus hannai tissues (gill and hepatopancreas under heavy metal exposure conditions (Cu, Zn, and Cd, 12 potential candidate housekeeping genes were subjected to expression stability based on the comprehensive ranking while integrating four different statistical algorithms (geNorm, NormFinder, BestKeeper, and ΔCT method. Results Expression stability in the gill subset was determined as RPL7 > RPL8 > ACTB > RPL3 > PPIB > RPL7A > EF1A > RPL4 > GAPDH > RPL5 > UBE2 > B-TU. On the other hand, the ranking in the subset for hepatopancreas was RPL7 > RPL3 > RPL8 > ACTB > RPL4 > EF1A > RPL5 > RPL7A > B-TU > UBE2 > PPIB > GAPDH. The pairwise variation assessed by the geNorm program indicates that two reference genes could be sufficient for accurate normalization in both gill and hepatopancreas subsets. Overall, both gill and hepatopancreas subsets recommended ribosomal protein genes (particularly RPL7 as stable references, whereas traditional housekeepers such as β-tubulin (B-TU and glyceraldehyde-3-phosphate dehydrogenase (GAPDH genes were ranked as unstable genes. The validation of reference gene selection was confirmed with the quantitative assay of MT transcripts. Conclusions The present analysis showed the importance of validating reference genes with multiple algorithmic approaches to select genes that are truly stable. Our results indicate that expression stability of a given reference gene could not always have consensus across tissue types. The data from this study could be a good guide for the future design of RT-qPCR studies with respect to metal regulation/detoxification and other related

A Study of Vegetation Development in Relation to Age of River Stabilization Structures Along a Channelized Segment of the Missouri River.

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1975-01-25

s.ame time period, the first shrub species begin to appear in the sites. Ulmus rubra ( slippery elm ), Celtis occidentalis (hackberry), and Platanus...boxelder), Ulmus americana (American elm ), Ulmus rubra ( slippery elm ), Fra:inus pennsyl- vanica (green ash), and Juglans nigra (black walnut). These may...be replaced by Tilia americana (basswood), the Ulmus americana (American elm ) and Ulmus rubra ( slippery elm ) remaining as co- dominants. Weaver (1960

Differential effects of Radix Paeoniae Rubra (Chishao on cytokine and chemokine expression inducible by mycobacteria

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Li James

2011-03-01

Full Text Available Abstract Background Upon initial infection with mycobacteria, macrophages secrete multiple cytokines and chemokines, including interleukin-6 (IL-6, IL-8 and tumor necrosis factor-α (TNF-α, to mediate host immune responses against the pathogen. Mycobacteria also induce the production of IL-10 via PKR activation in primary human monocytes and macrophages. As an anti-inflammatory cytokine, over-expression of IL-10 may contribute to mycobacterial evasion of the host immunity. Radix Paeoniae Rubra (RPR, Chishao, a Chinese medicinal herb with potentials of anti-inflammatory, hepatoprotective and neuroprotective effects, is used to treat tuberculosis. This study investigates the immunoregulatory effects of RPR on primary human blood macrophages (PBMac during mycobacterial infection. Methods The interaction of Bacillus Calmette-Guerin (BCG with PBMac was used as an experimental model. A series of procedures involving solvent extraction and fractionation were used to isolate bioactive constituents in RPR. RPR-EA-S1, a fraction with potent immunoregulatory effects was obtained with a bioactivity guided fractionation scheme. PBMac were treated with crude RPR extracts or RPR-EA-S1 before BCG stimulation. The expression levels of IL-6, IL-8, IL-10 and TNF-α were measured by qPCR and ELISA. Western blotting was used to determine the effects of RPR-EA-S1 on signaling kinases and transcriptional factors in the BCG-activated PBMac. Results In BCG-stimulated macrophages, crude RPR extracts and fraction RPR-EA-S1 specifically inhibited IL-10 production while enhanced IL-8 expression at both mRNA and protein levels without affecting the expressions of IL-6 and TNF-α. Inhibition of BCG-induced IL-10 expression by RPR-EA-S1 occurred in a dose- and time-dependent manner. RPR-EA-S1 did not affect the phosphorylation of cellular protein kinases including MAPK, Akt and GSK3β. Instead, it suppressed the degradation of IκBα in the cytoplasm and inhibited the

Draft Genome of Scalindua rubra, Obtained from the Interface Above the Discovery Deep Brine in the Red Sea, Sheds Light on Potential Salt Adaptation Strategies in Anammox Bacteria.

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Speth, Daan R; Lagkouvardos, Ilias; Wang, Yong; Qian, Pei-Yuan; Dutilh, Bas E; Jetten, Mike S M

2017-07-01

Several recent studies have indicated that members of the phylum Planctomycetes are abundantly present at the brine-seawater interface (BSI) above multiple brine pools in the Red Sea. Planctomycetes include bacteria capable of anaerobic ammonium oxidation (anammox). Here, we investigated the possibility of anammox at BSI sites using metagenomic shotgun sequencing of DNA obtained from the BSI above the Discovery Deep brine pool. Analysis of sequencing reads matching the 16S rRNA and hzsA genes confirmed presence of anammox bacteria of the genus Scalindua. Phylogenetic analysis of the 16S rRNA gene indicated that this Scalindua sp. belongs to a distinct group, separate from the anammox bacteria in the seawater column, that contains mostly sequences retrieved from high-salt environments. Using coverage- and composition-based binning, we extracted and assembled the draft genome of the dominant anammox bacterium. Comparative genomic analysis indicated that this Scalindua species uses compatible solutes for osmoadaptation, in contrast to other marine anammox bacteria that likely use a salt-in strategy. We propose the name Candidatus Scalindua rubra for this novel species, alluding to its discovery in the Red Sea.

Genomic characterization and expression profiles upon bacterial infection of a novel cystatin B homologue from disk abalone (Haliotis discus discus).

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Premachandra, H K A; Wan, Qiang; Elvitigala, Don Anushka Sandaruwan; De Zoysa, Mahanama; Choi, Cheol Young; Whang, Ilson; Lee, Jehee

2012-12-01

Cystatins are a large family of cysteine proteinase inhibitors which are involved in diverse biological and pathological processes. In the present study, we identified a gene related to cystatin superfamily, AbCyt B, from disk abalone Haliotis discus discus by expressed sequence tag (EST) analysis and BAC library screening. The complete cDNA sequence of AbCyt B is comprised of 1967 nucleotides with a 306 bp open reading frame (ORF) encoding for 101 amino acids. The amino acid sequence consists of a single cystatin-like domain, which has a cysteine proteinase inhibitor signature, a conserved Gly in N-terminal region, QVVAG motif and a variant of PW motif. No signal peptide, disulfide bonds or carbohydrate side chains were identified. Analysis of deduced amino acid sequence revealed that AbCyt B shares up to 44.7% identity and 65.7% similarity with the cystatin B genes from other organisms. The genomic sequence of AbCyt B is approximately 8.4 Kb, consisting of three exons and two introns. Phylogenetic tree analysis showed that AbCyt B was closely related to the cystatin B from pacific oyster (Crassostrea gigas) under the family 1.Functional analysis of recombinant AbCyt B protein exhibited inhibitory activity against the papain, with almost 84% inhibition at a concentration of 3.5 μmol/L. In tissue expression analysis, AbCyt B transcripts were expressed abundantly in the hemocyte, gill, mantle, and digestive tract, while weakly in muscle, testis, and hepatopancreas. After the immune challenge with Vibrio parahemolyticus, the AbCyt B showed significant (P<0.05) up-regulation of relative mRNA expression in gill and hemocytes at 24 and 6 h of post infection, respectively. These results collectively suggest that AbCyst B is a potent inhibitor of cysteine proteinases and is also potentially involved in immune responses against invading bacterial pathogens in abalone. Copyright © 2012 Elsevier Ltd. All rights reserved.

Coordinated regulation of anthocyanin biosynthesis in Chinese bayberry (Myrica rubra) fruit by a R2R3 MYB transcription factor.

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Niu, Shan-Shan; Xu, Chang-Jie; Zhang, Wang-Shu; Zhang, Bo; Li, Xian; Lin-Wang, Kui; Ferguson, Ian B; Allan, Andrew C; Chen, Kun-Song

2010-03-01

Chinese bayberry (Myrica rubra) is a fruit crop with cultivars producing fruit ranging from white (Shuijing, SJ) to red (Dongkui, DK) and dark red-purple (Biqi, BQ), as a result of different levels of anthocyanin accumulation. Genes encoding the anthocyanin biosynthesis enzymes chalcone synthase, chalcone isomerase, flavanone 3-hydroxylase (F3H), flavonoid 3'-hydroxylase (F3'H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS) and UDPglucose: flavonoid 3-O-glucosyltransferase (UFGT), as well as MrMYB1, a R2R3 MYB transcription factor homologous to known activators of anthocyanin biosynthesis, were isolated from ripe fruit of BQ. Differences in mRNA abundance of MrF3H, MrF3'H, MrDFR1, MrANS and MrUFGT were highly correlated with differential accumulation of anthocyanins between cultivars, suggesting coordinated regulation by transcription factors. The transcript level of MrMYB1 was strongly associated with the anthocyanin content in ripe fruit of the three cultivars, as well as different anthocyanin containing tissues of BQ fruit. Fruit bagging strongly inhibited anthocyanin accumulation in fruit as well as the expression of all anthocyanin biosynthetic genes and MrMYB1. Overexpression of MrMYB1 stimulated both anthocyanin accumulation and activated an Arabidopsis-DFR promoter in tobacco (Nicotiana tabacum). MrMYB1d, an allele with a 1 bp deletion at nucleotide 30 of coding sequence, was observed in SJ and DK fruit, suggesting that a nonsense mutation of the MYB1 protein may be responsible for no or low expression of MYB1 in the white and red fruit. These results show that coordinated expression of multiple biosynthetic genes is involved in anthocyanin accumulation in Chinese bayberry fruit, and this is regulated by MrMYB1.

Effects of tributyltin and benzo[a]pyrene on the immune-associated activities of hemocytes and recovery responses in the gastropod abalone, Haliotis diversicolor.

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Gopalakrishnan, Singaram; Huang, Wei-Bin; Wang, Qiang-Wei; Wu, Man-Li; Liu, Jie; Wang, Ke-Jian

2011-08-01

Our previous study reports that short-term exposure to sublethal concentrations of benzo[a]pyrene (BaP) induces immunomodulation in the gastropod abalone, Haliotis diversicolor. In the present study, it was further observed that long-term chronic exposure to sublethal concentrations of BaP modulated the immunocompetence of abalones in terms of the change in activity of the antioxidant and immune associated parameters tested. In addition, the effect of tributyltin (TBT), another important genotoxicant in the aquatic environment, was investigated. Exposure of abalones to sublethal concentrations of TBT and BaP for 21 days resulted in significant decrease of total hemocyte count, phagocytosis, membrane stability and lysozyme activity. Conversely induction of extra and intra cellular superoxide generation, nitric oxide, nitric oxide synthase and myeloperoxidase activity was present when the abalones were exposed to TBT and BaP. Most of the immune associated parameters tested showed clear time dependent response to both toxicants. Within 14 days after the 21 day exposure to BaP, recovery was observed as evidenced by most of the parameters returning to their normal level. However, no recovery was observed within 14 days after the 21 day exposure to TBT as evidenced by continued elevation of intra cellular superoxide and nitrite production and decrease in THC, membrane stability and lysozyme activity. This suggested a prolonged TBT-induced impact on the immune reaction and possibly more damage than that caused by BaP. Overall the results suggest that chronic exposure to sublethal concentrations of TBT or BaP causes modulations in the immunocompetence of abalones with most of the immune associated parameters tested being stimulated, and this might be harmful to the host. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of the dietary administration of sodium alginate on the immune responses and disease resistance of Taiwan abalone, Haliotis diversicolor supertexta.

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Cheng, Winton; Yu, Jyun-Sian

2013-03-01

Sodium alginate extracted from brown algae was reported to enhance the immune response and resistance of fish and shrimp. In this study, survival rates of the abalone, Haliotis diversicolor supertexta, against Vibrio parahaemolyticus, and its non-specific immune parameters such as the total haemocyte count (THC), phenoloxidase (PO) activity, respiratory bursts, superoxide dismutase (SOD) activity, phagocytic activity, and clearance efficiency to V. parahaemolyticus by H. diversicolor supertexta were determined when abalone (4.5 ± 0.4 g) were fed diets containing sodium alginate at 0, 1.0, 2.0, and 3.0 g kg⁻¹. Abalone fed a diet containing sodium alginate at 2.0 and 3.0 g kg⁻¹ for 14 days and at 1.0 g kg⁻¹ for 21 days had significantly higher survival rates than those fed the control diet after challenge with V. parahaemolyticus. The relative survival percentages of abalone fed the 1.0, 2.0, and 3.0 g kg⁻¹ sodium alginate-containing diets for 14 and 21 days were 16.1%, 40.0%, and 48.0%, and 63.6%, 27.3% and 22.6%, respectively. The PO activity, respiratory bursts, SOD activity, and phagocytic activity and clearance efficiency of V. parahaemolyticus of abalone fed the sodium alginate-containing diets at 1.0, 2.0, and 3.0 g kg⁻¹ were significantly higher than those of abalone fed the control diet for 14 days. After 21 days, the PO activity, respiratory bursts, SOD activity, and phagocytic activity and clearance efficiency of V. parahaemolyticus by abalone fed the sodium alginate-containing diet at 1.0 g kg⁻¹ were significantly higher than those of abalone fed the other diets. It was concluded that sodium alginate can be used as an immunostimulant for abalone through dietary administration to enhance immune responses of abalone and resistance against V. parahaemolyticus, which were related to the dose and timing of administration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Antimicrobial and Antitumor Activities of Novel Peptides Derived from the Lipopolysaccharide- and β-1,3-Glucan Binding Protein of the Pacific Abalone Haliotis discus hannai

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Bo-Hye Nam

2016-12-01

Full Text Available Antimicrobial peptides are a pivotal component of the invertebrate innate immune system. In this study, we identified a lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP gene from the pacific abalone Haliotis discus hannai (HDH, which is involved in the pattern recognition mechanism and plays avital role in the defense mechanism of invertebrates immune system. The HDH-LGBP cDNA consisted of a 1263-bp open reading frame (ORF encoding a polypeptide of 420 amino acids, with a 20-amino-acid signal sequence. The molecular mass of the protein portion was 45.5 kDa, and the predicted isoelectric point of the mature protein was 4.93. Characteristic potential polysaccharide binding motif, glucanase motif, and β-glucan recognition motif were identified in the LGBP of HDH. We used its polysaccharide-binding motif sequence to design two novel antimicrobial peptide analogs (HDH-LGBP-A1 and HDH-LGBP-A2. By substituting a positively charged amino acid and amidation at the C-terminus, the pI and net charge of the HDH-LGBP increased, and the proteins formed an α-helical structure. The HDH-LGBP analogs exhibited antibacterial and antifungal activity, with minimal effective concentrations ranging from 0.008 to 2.2 μg/mL. Additionally, both were toxic against human cervix (HeLa, lung (A549, and colon (HCT 116 carcinoma cell lines but not much on human umbilical vein cell (HUVEC. Fluorescence-activated cell sorter (FACS analysis showed that HDH-LGBP analogs disturb the cancer cell membrane and cause apoptotic cell death. These results suggest the use of HDH-LGBP analogs as multifunctional drugs.

Environmental Assessment for the Aeromedical Evacuation Formal Training Unit, Wright-Patterson Air Force Base

Science.gov (United States)

2012-05-01

pennsylvanica), White Ash (Fraxinus americana), Shingle Oak (Quercus imbricaria), Northern Red Oak (Quercus rubra), Slippery Elm (Ulmus rubra...American Elm (Ulmus americana), Eastern Cottonwood (Populus deltoides), Silver Maple (Acer saccharinum), Sassafras (Sassafras albidum), Post Oak (Quercus

Effects of ocean acidification with pCO2 diurnal fluctuations on survival and larval shell formation of Ezo abalone, Haliotis discus hannai.

Science.gov (United States)

Onitsuka, Toshihiro; Takami, Hideki; Muraoka, Daisuke; Matsumoto, Yukio; Nakatsubo, Ayumi; Kimura, Ryo; Ono, Tsuneo; Nojiri, Yukihiro

2018-03-01

This study assessed the effects of constant and diurnally fluctuating pCO 2 on development and shell formation of larval abalone Haliotis discus hannai. The larvae was exposed to different pCO 2 conditions; constant [450, 800, or 1200 μatm in the first experiment (Exp. I), 450 or 780 μatm in the second experiment (Exp. II)] or diurnally fluctuating pCO 2 (800 ± 400 or 1200 ± 400 μatm in Exp. I, 450 ± 80, 780 ± 200 or 780 ± 400 μatm in Exp. II). Mortality, malformation rates or shell length of larval abalone were not significantly different among the 450, 800, and 800 ± 400 μatm pCO 2 treatments. Meanwhile, significantly higher malformation rates and smaller shells were detected in the 1200 and 1200 ± 400 μatm pCO 2 treatments than in the 450 μatm pCO 2 treatment. The negative impacts were greater in the 1200 ± 400 μatm than in the 1200 μatm. Shell length and malformation rate of larval abalone were related with aragonite saturation state (Ω-aragonite) in experimental seawater, and greatly changed around 1.1 of Ω-aragonite which corresponded to 1000-1300 μatm pCO 2 . These results indicate that there is a pCO 2 threshold associated with Ω-aragonite in the seawater, and that pCO 2 fluctuations produce additional negative impacts on abalone when above the threshold. Clear relationships were detected between abalone fitness and the integrated pCO 2 value over the threshold, indicating that the effects of OA on development and shell formation of larval abalone can be determined by intensity and time of exposure to pCO 2 over the threshold. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of novel polymorphic microsatellite loci identified in the Korean Pacific Abalone (Haliotis diversicolor supertexta (Haliotidae)) in the genetic characterization of wild and released populations.

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An, Hye Suck; Lee, Jang Wook; Hong, Seong Wan

2012-01-01

The small abalone, Haliotis diversicolor supertexta, of the family Haliotidae, is one of the most important species of marine shellfish in eastern Asia. Over the past few decades, this species has drastically declined in Korea. Thus, hatchery-bred seeds have been released into natural coastal areas to compensate for the reduced fishery resources. However, information on the genetic background of the small abalone is scarce. In this study, 20 polymorphic microsatellite DNA markers were identified using next-generation sequencing techniques and used to compare allelic variation between wild and released abalone populations in Korea. Using high-throughput genomic sequencing, a total of 1516 (2.26%; average length of 385 bp) reads containing simple sequence repeats were obtained from 86,011 raw reads. Among the 99 loci screened, 28 amplified successfully, and 20 were polymorphic. When comparing allelic variation between wild and released abalone populations, a total of 243 different alleles were observed, with 18.7 alleles per locus. High genetic diversity (mean heterozygosity = 0.81; mean allelic number = 15.5) was observed in both populations. A statistical analysis of the fixation index (F(ST)) and analysis of molecular variance (AMOVA) indicated limited genetic differences between the two populations (F(ST) = 0.002, p > 0.05). Although no significant reductions in the genetic diversity were found in the released population compared with the wild population (p > 0.05), the genetic diversity parameters revealed that the seeds released for stock abundance had a different genetic composition. These differences are likely a result of hatchery selection and inbreeding. Additionally, all the primer pair sets were effectively amplified in another congeneric species, H. diversicolor diversicolor, indicating that these primers are useful for both abalone species. These microsatellite loci may be valuable for future aquaculture and population genetic studies aimed at

Leaf anatomical changes in Populus trichocarpa, Quercus rubra, Pseudotsuga menziesii and Pinus ponderosa exposed to enhanced ultraviolet-B radiation

International Nuclear Information System (INIS)

Nagel, L.M.; Bassman, J.H.; Edwards, G.E.; Robberecht, R.; Franceshi, V.R.

1998-01-01

Leaf anatomical characteristics are important in determining the degree of injury sustained when plants are exposed to natural and enhanced levels of ultraviolet-B (UV-B) radiation (280–320 nm). The degree to which leaf anatomy can adapt to the increasing levels of UV-B radiation reaching the earth's surface is poorly understood in most tree species. We examined four tree species, representing a wide range of leaf anatomical characteristics, to determine responses of leaf area, specific leaf weight, and leaf tissue parameters after exposure to ambient and enhanced levels of UV-B radiation. Seedlings were grown in a greenhouse with photosynthetically active radiation of 39 mol m −2 day −1 and under one of three daily irradiances of biologically effective UV-B radiation (UV-BBE) supplied for 10 h per day: (1) approximate ambient level received at Pullman, Washington on June 21 (1 x ); two times ambient (2 x ), or three times ambient (3 x ). We hypothesized the response of each species to UV-B radiation would be related to inherent anatomical differences. We found that the conifers responded anatomically to nearly an equal degree as the broad-leaved trees, but that different tissues were involved. Populus trichocarpa, an indeterminate broadleaf species, showed significantly thicker palisade parenchyma in recently mature leaves at the 3 x level and in older leaves under the 2 x level. In addition, individual leaf area was generally greater with increased UV-B irradiance. Quercus rubra, a semi-determinate broadleaf species, exhibited significantly thicker palisade parenchyma at the 2 x and 3 x levels as compared to controls. Psuedotsuga menziesii, an evergreen coniferous species with bifacially flattened needles, and Pinus ponderosa, an evergreen coniferous species with a complete hypodermis, showed no significant change in leaf area or specific leaf weight under enhanced UV-B radiation. Epidermal thickness was unchanged in P. menziesii. However, P. ponderosa

Nacre in Abalone Shell: Organic and Inorganic Components and their effects to the Formation and Mechanical Properties

Science.gov (United States)

Lopez, Maria Isabel

Abalone nacre is a natural composite that exhibits exceptional mechanical properties due to its organization that extends to various levels of hierarchy. Most of the toughness has been attributed by nacre's third level of hierarchy which entitles a brick and mortar structure consisting of the CaCO3 tiles and organic interlayers. However, there are other important components that are vital to the structure and strength of red abalone nacre. The process of formation of red abalone (Haliotis rufescens) nacre following periods of growth interruption, taking into consideration important environmental factors (access to food and temperature) and to employ high-magnification characterization techniques (scanning electron microscopy and transmission electron microscopy) to better understand how the soft tissue (e.g. epithelium and organic membrane) influences the mechanism of growth. The structure-property relationship of red abalone (Haliotis rufescens) nacre, focusing in the individual constituents (isolated mineral and isolated organic component) and comparing that to the integrated structure. Mechanical tests such as, tensile tests, microscratch, and nanoindentation is performed on the isolated organic constituent and the isolated mineral of red abalone shell. Specimens are characterized by SEM to verify the toughening and deformation mechanisms. Results obtained from the isolated mineral validate the importance of the organic constituent as the mechanical properties decline greatly as the organic component is removed. This approach forms a general picture of the mechanical response of the organic interlayers and growth bands and their effect on the toughness of the abalone nacre. These results are significant to understand the important characteristics of abalone nacre, such as the structure and mechanical properties, and an attempt to aid in improving the latest attempts to produce novel nacre-inspired materials.

Two duplicated chicken-type lysozyme genes in disc abalone Haliotis discus discus: molecular aspects in relevance to structure, genomic organization, mRNA expression and bacteriolytic function.

Science.gov (United States)

Umasuthan, Navaneethaiyer; Bathige, S D N K; Kasthuri, Saranya Revathy; Wan, Qiang; Whang, Ilson; Lee, Jehee

2013-08-01

Lysozymes are crucial antibacterial proteins that are associated with catalytic cleavage of peptidoglycan and subsequent bacteriolysis. The present study describes the identification of two lysozyme genes from disc abalone Haliotis discus discus and their characterization at sequence-, genomic-, transcriptional- and functional-levels. Two cDNAs and BAC clones bearing lysozyme genes were isolated from abalone transcriptome and BAC genomic libraries, respectively and sequences were determined. Corresponding deduced amino acid sequences harbored a chicken-type lysozyme (LysC) family profile and exhibited conserved characteristics of LysC family members including active residues (Glu and Asp) and GS(S/T)DYGIFQINS motif suggested that they are LysC counterparts in disc abalone and designated as abLysC1 and abLysC2. While abLysC1 represented the homolog recently reported in Ezo abalone [1], abLysC2 shared significant identity with LysC homologs. Unlike other vertebrate LysCs, coding sequence of abLysCs were distributed within five exons interrupted by four introns. Both abLysCs revealed a broader mRNA distribution with highest levels in mantle (abLysC1) and hepatopancreas (abLysC2) suggesting their likely main role in defense and digestion, respectively. Investigation of temporal transcriptional profiles post-LPS and -pathogen challenges revealed induced-responses of abLysCs in gills and hemocytes. The in vitro muramidase activity of purified recombinant (r) abLysCs proteins was evaluated, and findings indicated that they are active in acidic pH range (3.5-6.5) and over a broad temperature range (20-60 °C) and influenced by ionic strength. When the antibacterial spectra of (r)abLysCs were examined, they displayed differential activities against both Gram positive and Gram negative strains providing evidence for their involvement in bacteriolytic function in abalone physiology. Copyright © 2013 Elsevier Ltd. All rights reserved.

The effect of heat waves, elevated [CO2 ] and low soil water availability on northern red oak (Quercus rubra L.) seedlings.

Science.gov (United States)

Bauweraerts, Ingvar; Wertin, Timothy M; Ameye, Maarten; McGuire, Mary Anne; Teskey, Robert O; Steppe, Kathy

2013-02-01

The frequency and intensity of heat waves are predicted to increase. This study investigates whether heat waves would have the same impact as a constant increase in temperature with the same heat sum, and whether there would be any interactive effects of elevated [CO2 ] and soil moisture content. We grew Quercus rubra seedlings in treatment chambers maintained at either ambient or elevated [CO2 ] (380 or 700 μmol CO2 mol(-1) ) with temperature treatments of ambient, ambient +3 °C, moderate heat wave (+6 °C every other week) or severe heat wave (+12 °C every fourth week) temperatures. Averaged over a 4-week period, and the entire growing season, the three elevated temperature treatments had the same average temperature and heat sum. Half the seedlings were watered to a soil water content near field capacity, half to about 50% of this value. Foliar gas exchange measurements were performed morning and afternoon (9:00 and 15:00 hours) before, during and after an applied heat wave in August 2010. Biomass accumulation was measured after five heat wave cycles. Under ambient [CO2 ] and well-watered conditions, biomass accumulation was highest in the +3 °C treatment, intermediate in the +6 °C heat wave and lowest in the +12 °C heat wave treatment. This response was mitigated by elevated [CO2 ]. Low soil moisture significantly decreased net photosynthesis (Anet ) and biomass in all [CO2 ] and temperature treatments. The +12 °C heat wave reduced afternoon Anet by 23% in ambient [CO2 ]. Although this reduction was relatively greater under elevated [CO2 ], Anet values during this heat wave were still 34% higher than under ambient [CO2 ]. We concluded that heat waves affected biomass growth differently than the same amount of heat applied uniformly over the growing season, and that the plant response to heat waves also depends on [CO2 ] and soil moisture conditions. © 2012 Blackwell Publishing Ltd.

Effects of waterborne Cu and Cd on anti-oxidative response, lipid peroxidation and heavy metals accumulation in abalone Haliotis discus hannai ino

Science.gov (United States)

Lei, Yanju; Zhang, Wenbing; Xu, Wei; Zhang, Yanjiao; Zhou, Huihui; Mai, Kangsen

2015-06-01

The aim of this study was to compare the effects of waterborne copper (Cu) and cadmium (Cd) on survival, anti-oxidative response, lipid peroxidation and metal accumulation in abalone Haliotis discus hannai. Experimental animals (initial weight: 7.49 g ± 0.01 g) were exposed to graded concentrations of waterborne Cu (0.02, 0.04, 0.06, 0.08 mg L-1) or Cd (0.025, 0.05, 0.25, 0.5 mg L-1) for 28 days, respectively. Activities of the anti-oxidative enzymes (catalase, CAT; superoxide dismutase, SOD; glutathione peroxidases, GPx; glutathione S-transferase, GST), contents of the reduced glutathione (GSH) and malondiadehyde (MDA) in the hepatopancreas, and metal accumulation in hepatopancreas and muscles were analyzed after 0, 1, 3, 6, 10, 15, 21, 28 days of metal exposure, respectively. Results showed that 0.04 mg L-1, 0.06 mg L--1 and 0.08 mg L-1 Cu caused 100% death of abalone on the 21st, 10th and 6th day, respectively. However, no dead abalone was found during the 28-day waterborne Cd exposure at all experimental concentrations. Generally, activities of SOD and GST in hepatopancreas under all Cu concentrations followed a decrease trend as the exposure time prolonged. However, these activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Activities of CAT in all Cu exposure treatments were higher than those in the control. These activities were firstly increased and then decreased to the control level and increased again during Cd exposure. Contents of MDA in hepatopancreas in all Cu treatments significantly increased first and then decreased to the control level. However, the MDA contents in hepatopancreas were not significantly changed during the 28-day Cd exposure. The metals accumulation in both hepatopancreas and muscles of abalone significantly increased with the increase of waterborne metals concentration and exposure time. These results indicated that H. discus hannai has a positive anti-oxidative defense

Evaluation of the grass mixture (Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp.) as Sb phyto-stabilizer in tailings and Sb-rich soils.

Science.gov (United States)

Aurora Armienta, M.; Beltrán-Villavicencio, Margarita; Ruiz-Villalobos, Carlos E.; Labastida, Israel; Ceniceros, Nora; Cruz, Olivia; Aguayo, Alejandra

2017-04-01

Green house experiments were carried out to evaluate the growth and Sb assimilation of a grass assemblage: Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp, in tailings and Sb-rich soils. Tailings and soil samples were obtained at the Mexican historical mining zone of Zimapán, Central México. More than 6 tailings impoundments are located at the town outskirts and constitute a contamination source from windblown and waterborne deposit on soils, besides acid mine drainage. Four substrates were used in the experiments: 100% tailings, 20% tailings + 80% soil, 50% tailings + 50% soil , and a soil sample far from tailings as a background. Concentrations of Sb ranged from 310 mg/kg to 413 mg/kg in tailings. A pH of 7.43, 1.27% organic matter, and high concentrations of N, K and P indicated adequate conditions for plant growth. The grass assemblage was raised during 21 days as indicated by OECD (Organisation for Economic Co-operation and Development) Guideline 208 Terrestrial Plant Test: Seedling Emergence and Seedling Growth Test. The highest Sb concentrations were measured in plants grown on tailings with 139 mg/kg in the aerial part and 883 mg/kg in roots. Concentrations of Sb decreased as the proportion of tailings diminished with 22.1 mg/kg in the aerial part and 10 mg/kg in roots corresponding to the plants grown in the 20 % tailings + 80% soil . Bioaccumulation (BAC) and bioconcentration factors (BF) of plants grown on tailings (BAC= 0.42, BCF=3.93) indicated their suitability as a phyto-stabilization option. The grass mixture may be thus applied to control windblown particulate tailings taking advantage to their tolerance to high Sb levels.

Stem rust (Puccinia graminis ssp. graminicola Urban its hosts and harmfulness in grasses grown for seed

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Maria Prończuk

2013-12-01

Full Text Available Stem rust development on four species of grasses was studied in field experiments conducted at Radzików in 1997-2001. Population of Puccinia graminis ssp. graminicola from different hosts was characterised and their harmfulness for grass grown for seed was estimated. The materials for study were ecotypes and strains of Lolium perenne, Festuca rubra, Poa pratensis and Deschampsia caespitosa collected in breeding nursery and cultivars and strains of L.perenne, F.rubra, P.pratensis cultivated for seed. It was found that the changes in environmental conditions during last years influenced earlier occurrence of stem rust on grasses in Poland. All examined species were the host of P.graminis ssp. graminicola, however the period of infection of particular hosts were different. L.perenne and D.caespitosa were infected in early summer but F.rubra and P.pratensis in late summer or in the autumn. Morphological analysis of spores of P.graminis ssp. graminicola have shoved significant differences between populations obtained from L.perenne and D.caespitosa. Some differences were found between populations from F.rubra and P.pratensis also, but they need more study. Every year occurrence of stem rust on L.perenne and D.caespitosa and its relation with spring temperature in Radzików indicated that populations of patogen could overwinter in local turf. Incidental appearance of stem rust on F.rubra and P.pratensis in centre of Poland allowed to suppose that spores of these forms might be transfer by wind from other regions. The investigation revealed that stem rust can be dangerous for L.perenne grown for seed when infection occurs at flowering time. It has been established that infection of F.rubra and P.pratensis in autumn should not be disregarded. Damages of leaves by P.graminis ssp. graminicola substantially limited plant heading in the next year.

A Regional Guidebook for Applying the Hydrogeomorphic Approach to the Functional Assessment of Forested Wetlands in Alluvial Valleys of East Texas

Science.gov (United States)

2010-10-01

plant species as the low-gradient riverine subclass. However, species such as American elm (Ulmus americana), slippery elm (Ulmus rubra), winged elm ...americana American elm Ulmus crassifolia cedar elm Ulmus rubra slippery elm Ulmus spp. elm Viburnum nudum possumhaw Vitis rotundifolia muscadine...laurel oak (Q. laurifolia), Shumard oak (Q. shumardii), elms (Ulmus sp.), sweetgum (Liquidambar styraciflua), southern magnolia (Magnolia

Case report

African Journals Online (AJOL)

raoul

21 sept. 2011 ... Pityriasis rubra pilaris and HIV infection. J Am Acad Dermatol. 1991; 24:703-705. This article on PubMed. 4. Sharma S, Weiss GR, Paulger B. Pityriasis rubra pilaris as an initial presentation of hepatocellular carcinoma. Dermatology. 1997; 194. (2):166-7. This article on PubMed. 5. Polat M, Lenk N, Ustun H, ...

Dietary ascorbic acid modulates the expression profile of stress protein genes in hepatopancreas of adult Pacific abalone Haliotis discus hannai Ino.

Science.gov (United States)

Wu, Chenglong; Wang, Jia; Xu, Wei; Zhang, Wenbing; Mai, Kangsen

2014-12-01

This study was conducted to investigate the effects of dietary ascorbic acid (AA) on transcriptional expression patterns of antioxidant proteins, heat shock proteins (HSP) and nuclear factor kappa B (NF-κB) in the hepatopancreas of Pacific abalone Haliotis discus hannai Ino (initial average length: 84.36 ± 0.24 mm) using real-time quantitative PCR assays. L-ascorbyl-2-molyphosphate (LAMP) was added to the basal diet to formulate four experimental diets containing 0.0, 70.3, 829.8 and 4967.5 mg AA equivalent kg(-1) diets, respectively. Each diet was fed to triplicate groups of adult abalone in acrylic tanks (200 L) in a flow-through seawater system. Each tank was stocked with 15 abalone. Animals were fed once daily (17:00) to apparent satiation for 24 weeks. The results showed that the dietary AA (70.3 mg kg(-1)) could significantly up-regulate the expression levels of Cu/Zn superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), feritin (FT) and heat shock protein 26 (HSP26) in the hepatopancreas of abalone in this treatment compared to the controls. However, the expression levels of Mn-SOD, glutathione peroxidase (GPX), thioredoxin peroxidase (TPx), selenium-binding protein (SEBP), HSP70 and HSP90 were significantly down-regulated. Compared with those in the group with 70.3 mg kg(-1) dietary AA, the expression levels of CAT, GST and HSP26 were decreased in abalone fed with very high dietary AA (4967.5 mg kg(-1)). In addition, significant up-regulations of expression levels of Mn-SOD, GPX, TPx, SEBP, FT, HSP70, HSP90 and NF-κB were observed in abalone fed with apparently excessive dietary AA (829.8 and 4967.5 mg kg(-1)) as compared to those fed 70.3 mg kg(-1) dietary AA. These findings showed that dietary AA influenced the expression levels of antioxidant proteins, heat shock proteins and NF-κB in the hepatopancreas of abalone at transcriptional level. Levels of dietary AA that appeared adequate (70.3 mg kg(-1)) reduced the oxidative stress

Detection and localisation of the abalone probiotic Vibrio midae SY9 and its extracellular protease, VmproA, within the digestive tract of the South African abalone, Haliotis midae.

Directory of Open Access Journals (Sweden)

Robert J Huddy

Full Text Available Probiotics have been widely reported to increase the growth rate of commercially important fish and shellfish by enhancing the digestion of ingested feed through the production of extracellular enzymes such as proteases and alginases. In order to investigate this further, the objective of this study was to localise the bacterial probiont Vibrio midae SY9 and one of the extracellular proteases it produces in the digestive tract of the South African abalone Haliotis midae. This was accomplished by inserting a promotorless gfp gene into the chromosome of the bacterium which was incorporated in an artificial, fishmeal-based abalone feed. In situ histological comparison of abalone fed either a basal diet or the basal diet supplemented with V. midae SY9::Tn10.52 using a cocktail of DNA probes to the gfp gene localised the probiont to the crop/stomach and intestinal regions of the H. midae digestive tract. Generally, the ingested probiotic bacterium occurred in association with feed and particulate matter within the crop/stomach and intestinal regions, as well as adhered to the wall of the crop/stomach. Histological immunohistochemical examination using polyclonal anti-VmproA antibodies localised an extracellular protease produced by V. midae SY9 to the H. midae crop/stomach and intestine where it appeared to be associated with feed and/or other particulate matter in the abalone gut. Thus the data suggests that V. midae SY9 colonises and/or adheres to the mucous lining of the abalone gut. Furthermore, the close association observed between the bacterium, its extracellular protease and ingested feed particles supports the theory that V. midae SY9 elevates in situ digestive enzyme levels and thus enhances feed digestion in farmed abalone.

Detection and localisation of the abalone probiotic Vibrio midae SY9 and its extracellular protease, VmproA, within the digestive tract of the South African abalone, Haliotis midae.

Science.gov (United States)

Huddy, Robert J; Coyne, Vernon E

2014-01-01

Probiotics have been widely reported to increase the growth rate of commercially important fish and shellfish by enhancing the digestion of ingested feed through the production of extracellular enzymes such as proteases and alginases. In order to investigate this further, the objective of this study was to localise the bacterial probiont Vibrio midae SY9 and one of the extracellular proteases it produces in the digestive tract of the South African abalone Haliotis midae. This was accomplished by inserting a promotorless gfp gene into the chromosome of the bacterium which was incorporated in an artificial, fishmeal-based abalone feed. In situ histological comparison of abalone fed either a basal diet or the basal diet supplemented with V. midae SY9::Tn10.52 using a cocktail of DNA probes to the gfp gene localised the probiont to the crop/stomach and intestinal regions of the H. midae digestive tract. Generally, the ingested probiotic bacterium occurred in association with feed and particulate matter within the crop/stomach and intestinal regions, as well as adhered to the wall of the crop/stomach. Histological immunohistochemical examination using polyclonal anti-VmproA antibodies localised an extracellular protease produced by V. midae SY9 to the H. midae crop/stomach and intestine where it appeared to be associated with feed and/or other particulate matter in the abalone gut. Thus the data suggests that V. midae SY9 colonises and/or adheres to the mucous lining of the abalone gut. Furthermore, the close association observed between the bacterium, its extracellular protease and ingested feed particles supports the theory that V. midae SY9 elevates in situ digestive enzyme levels and thus enhances feed digestion in farmed abalone.

Environmental research - development of the material balance of oak tree ecosystems on quaternary spoil bank substrates of coal mines; Umweltforschung - Entwicklung des Stoffhaushaltes von Eichenoekosystemen auf quartaeren Kippsubstraten des Braunkohlenbergbaues

Energy Technology Data Exchange (ETDEWEB)

Katzur, J.; Knoche, D.

2000-07-01

Investigations have shown that even the very first forest generation on spoil banks already have high vitality. However, it is well known that pioneering terrestrial ecosystems have a high water and material turnover dynamics which will quickly influence the soil at that site but is not an indication of the development of a stable ecosystem. Long-term measurements were therefore made in oak forest ecosystems on quaternary spoil bank sands in order to achieve a quantification (Boxberg: Q. rubra L., 2 years; Kleinleipisch: Q. rubra L., 21 years; Annahuetter: Q. rubra L., 63 years). The results were compared with a virgin soil reference site (Neusorgefeld: Q. rubra L., 41 years). [German] Seit Jahrzehnten praegen Braunkohlentagebaue das Landschaftsbild und den Wasserhaushalt der Niederlausitz. Bislang wurden ca. 770 km{sup 2} ueberwiegend forstlich genutzter Flaechen devastiert und auf 2.100 km{sup 2} rund 9,5 Mrd. m{sup 3} statischer Grundwasservorraete entnommen. Im Zuge der seit 1990 drastisch verringerten Kohlefoerderung und forcierten Bergbausanierung erreicht die Rekultivierungsflaeche zwischenzeitlich rund 450 km{sup 2}, wobei die forstliche Folgenutzung mit 60% der Flaeche dominiert. Zahlreiche wachstumskundliche Untersuchungen belegen, dass sich bereits in der ersten Waldgeneration auf Kippe wuechsige und vitale Bestaende etablieren. Vegetations- und ertragskundliche Parameter wie z.B. Artenzusammensetzung, Naehrstoffversorgung, laufender Zuwachs oder Vorratshaltung sind jedoch per se noch keine hinreichenden Kriterien zur Einschaetzung der Entwicklungsdynamik und damit des angestrebten Rekultivierungserfolgs. Bekannterweise zeichnen sich im Aufbau befindliche terrestrische Oekosysteme generell durch eine ausgepraegte Wasser- und Stoffdynamik aus, welche im Zuge bodengenetischer Prozesse meist eine rasche Standortveraenderung bewirkt. Da das Standortpotential zum Rekultivierungszeitpunkt nicht prognostiziert werden kann, ist offen, ob sich bereits in der

Vegetation in the Flood Plain Adjacent to the Mississippi River between Cairo, Illinois, and St. Paul, Minnesota, and in the Flood Plain of the Illinois River between Grafton, Illinois, and Chicago, and the Possible Impacts That Will Result from the Construction of L & D 26 and the Associated Increase in Barge Traffic,

Science.gov (United States)

1975-01-20

and pecan ( Carya illinoensis ). In the southernmost region of the study area (i.e., Alexander and Union counties, Illinois), swamp cottonwood is a...ash (Fraxinus lanceolata), pecan ( Carya illinoensis ), box elder (Acer negundo), and red mulberry (Morus rubra). Shrubs occurring in the Silver Maple...americana), green ash (Fraxinus lanceolata), pecan ( Carya illinoensis ), sugarberry (Celtis laevigata), and red mulberry (Morus rubra). Also

The toxic dinoflagellate Dinophysis acuminata harbors permanent chloroplasts of cryptomomad prigin, not kleptochloroplasts

DEFF Research Database (Denmark)

Garcia, Lydia; Moestrup, Øjvind; Hansen, Per Juel

2010-01-01

of Dinophysis acuminata was established by feeding it the phototrophic ciliate Mesodinium rubrum (= Myrionecta rubra), which again was fed the cryptophyte Teleaulax amphioxeia. Molecular analysis comprising the nucleomorph LSU and two chloroplast markers (tufA gene and a fragment from the end of 16S r......DNA to the beginning of 23S rDNA) resulted in identical sequences for the three organisms. Yet, transmission electron microscopy of the three organisms revealed that several chloroplast features separated D. acuminata from both T. amphioxeia and M. rubrum. The thylakoid arrangement, the number of membranes around...

Hierarchical super-structure identified by polarized light microscopy, electron microscopy and nanoindentation: Implications for the limits of biological control over the growth mode of abalone sea shells

Directory of Open Access Journals (Sweden)

Schneider Andreas S

2012-09-01

Full Text Available Abstract Background Mollusc shells are commonly investigated using high-resolution imaging techniques based on cryo-fixation. Less detailed information is available regarding the light-optical properties. Sea shells of Haliotis pulcherina were embedded for polishing in defined orientations in order to investigate the interface between prismatic calcite and nacreous aragonite by standard materialographic methods. A polished thin section of the interface was prepared with a defined thickness of 60 μm for quantitative birefringence analysis using polarized light and LC-PolScope microscopy. Scanning electron microscopy images were obtained for comparison. In order to study structural-mechanical relationships, nanoindentation experiments were performed. Results Incident light microscopy revealed a super-structure in semi-transparent regions of the polished cross-section under a defined angle. This super-structure is not visible in transmitted birefringence analysis due to the blurred polarization of small nacre platelets and numerous organic interfaces. The relative orientation and homogeneity of calcite prisms was directly identified, some of them with their optical axes exactly normal to the imaging plane. Co-oriented "prism colonies" were identified by polarized light analyses. The nacreous super-structure was also visualized by secondary electron imaging under defined angles. The domains of the super-structure were interpreted to consist of crystallographically aligned platelet stacks. Nanoindentation experiments showed that mechanical properties changed with the same periodicity as the domain size. Conclusions In this study, we have demonstrated that insights into the growth mechanisms of nacre can be obtained by conventional light-optical methods. For example, we observed super-structures formed by co-oriented nacre platelets as previously identified using X-ray Photo-electron Emission Microscopy (X-PEEM [Gilbert et al., Journal of the

Study on the Effects of Diverting Water into Upper Burnt Pocket, Navigation Pool Number 18, Illinois and A Field Test of the Regression Simulation Model Previously Developed on Navigation Pool Number 8.

Science.gov (United States)

1981-03-01

latifolia L. Commuon Cattail ULMACEAE Celtis occidentalis L. Hackberry Ulmus rubra Muhl. Slippery Elm Ulmus americana L. American Elm URTICACEAE...Populus deltoides Marsh. Cottonwood Celtis occidentalis L. Hackberry Ulmus rubra Muhl. Slippery Elm Ulmus americana L. American Elm *Dominant or most...Cryptochironomus sn. Tnta - Tanytarsus sp. Phys - Physa sp. Crcl n Crytoclido elm sp. Epio - Epoicocladius sp. Trun - Truncilla sp, Elnf - Einfeldia sp. Eusi

In vivo synthesis of nanomaterials in plants: location of silver nanoparticles and plant metabolism

Science.gov (United States)

Marchiol, Luca; Mattiello, Alessandro; Pošćić, Filip; Giordano, Cristiana; Musetti, Rita

2014-03-01

Metallic nanoparticles (MeNPs) can be formed in living plants by reduction of the metal ions absorbed as soluble salts. It is very likely that plant metabolism has an important role in MeNP biosynthesis. The in vivo formation of silver nanoparticles (AgNPs) was observed in Brassica juncea, Festuca rubra and Medicago sativa. Plants were grown in Hoagland's solution for 30 days and then exposed for 24 h to a solution of 1,000 ppm AgNO3. In the leaf extracts of control plants, the concentrations of glucose, fructose, ascorbic acid, citric acid and total polyphenols were determined. Total Ag content in plant fractions was determined by inductively coupled plasma atomic emission spectroscopy. Despite the short exposure time, the Ag uptake and translocation to plant leaves was very high, reaching 6,156 and 2,459 mg kg-1 in B. juncea and F. rubra, respectively. Ultrastructural analysis was performed by transmission electron microscopy (TEM), and AgNPs were detected by TEM X-ray microanalysis. TEM images of plant fractions showed the in vivo formation of AgNPs in the roots, stems and leaves of the plants. In the roots, AgNPs were present in the cortical parenchymal cells, on the cell wall of the xylem vessels and in regions corresponding to the pits. In leaf tissues, AgNPs of different sizes and shapes were located close to the cell wall, as well as in the cytoplasm and within chloroplasts. AgNPs were not observed in the phloem of the three plant species. This is the first report of AgNP synthesis in living plants of F. rubra. The contents of reducing sugars and antioxidant compounds, proposed as being involved in the biosynthesis of AgNPs, were quite different between the species, thus suggesting that it is unlikely that a single substance is responsible for this process.

Haliotis diversicolor supertexta

African Journals Online (AJOL)

Jane

2011-08-03

Aug 3, 2011 ... production in the world including Australia, China, Japan,. Korea, Mexico ... reverse transcribed to synthesize first strand cDNA at 42°C for 1 h. Then first ... cDNA clones, a SMART cDNA library was constructed. Total RNA with ...

Haliotis tuberculata hemocyanin (HtH): analysis of oligomeric stability of HtH1 and HtH2, and comparison with keyhole limpet hemocyanin KLH1 and KLH2.

Science.gov (United States)

Harris, J R; Scheffler, D; Gebauer, W; Lehnert, R; Markl, J

2000-12-01

The multimeric/higher oligomeric states of the two isoforms of Haliotis tuberculata hemocyanin (HtH1 and HtH2) have been assessed by transmission electron microscopy (TEM) of negatively stained specimens, for comparison with previously published structural data from keyhole limpet hemocyanin (KLH1 and KLH2) [see Harris, J.R., Gebauer, W., Guderian, F.U., Markl, J., 1997a. Keyhole limpet hemocyanin (KLH), I: Reassociation from Immucothel followed by separation of KLH1 and KLH2. Micron, 28, 31-41; Harris, J.R., Gebauer, W., Söhngen, S.M., Nermut, M.V., Markl, J., 1997b. Keyhole limpet hemocyanin (KLH). II: Characteristic reassociation properties of purified KLH1 and KLH2. Micron, 28, 43-56; Harris, J.R., Gebauer, W., Adrian, M., Markl, J., 1998. Keyhole limpet hemocyanin (KLH): Slow in vitro reassociation of KLH1 and KLH2 from Immucothel. Micron, 29, 329-339]. In purified samples of both HtH isoforms, the hollow cylindrical ca 8MDa didecamer predominates together with a small number of decamers, but tri- and longer multidecamers are detectable only in the HtH2. The stability of the two HtH isoforms under varying ionic conditions have been monitored, thereby enabling conditions for the production of stable decamers to be established. The ability of these decamers to reform multimers in the presence of 10 and 100mM concentrations of calcium and magnesium ions in Tris-HCl buffer (pH 7.4), and also of individual HtH1 and HtH2 subunits (produced by pH 9.6 dissociation in glycine-NaOH buffer), to reassociate in the presence of calcium and magnesium ions, has been assessed. For the HtH1 decamers, the predominant multimeric product is the didecamer at 10 and 100mM calcium and magnesium concentrations, whereas for the HtH2 decamers, large numbers of multidecamers are produced, with the reaction proceeding more completely at the higher calcium and magnesium concentration. With the HtH1 subunit, reassociation in the presence of 10 and 100mM calcium and magnesium ions yielded

Application of Novel Polymorphic Microsatellite Loci Identified in the Korean Pacific Abalone (Haliotis diversicolor supertexta (Haliotidae in the Genetic Characterization of Wild and Released Populations

Directory of Open Access Journals (Sweden)

Seong Wan Hong

2012-08-01

Full Text Available The small abalone, Haliotis diversicolor supertexta, of the family Haliotidae, is one of the most important species of marine shellfish in eastern Asia. Over the past few decades, this species has drastically declined in Korea. Thus, hatchery-bred seeds have been released into natural coastal areas to compensate for the reduced fishery resources. However, information on the genetic background of the small abalone is scarce. In this study, 20 polymorphic microsatellite DNA markers were identified using next-generation sequencing techniques and used to compare allelic variation between wild and released abalone populations in Korea. Using high-throughput genomic sequencing, a total of 1516 (2.26%; average length of 385 bp reads containing simple sequence repeats were obtained from 86,011 raw reads. Among the 99 loci screened, 28 amplified successfully, and 20 were polymorphic. When comparing allelic variation between wild and released abalone populations, a total of 243 different alleles were observed, with 18.7 alleles per locus. High genetic diversity (mean heterozygosity = 0.81; mean allelic number = 15.5 was observed in both populations. A statistical analysis of the fixation index (F_ST and analysis of molecular variance (AMOVA indicated limited genetic differences between the two populations (F_ST = 0.002, p > 0.05. Although no significant reductions in the genetic diversity were found in the released population compared with the wild population (p > 0.05, the genetic diversity parameters revealed that the seeds released for stock abundance had a different genetic composition. These differences are likely a result of hatchery selection and inbreeding. Additionally, all the primer pair sets were effectively amplified in another congeneric species, H. diversicolor diversicolor, indicating that these primers are useful for both abalone species. These microsatellite loci

Vegetation Evaluation and Recommendations: Dredge Material Placement Areas and Adjacent Lands, Kaskaskia River Navigation Project, New Athens to Fayetteville.

Science.gov (United States)

1981-06-03

cottonwood), Salix interior (sandbar willow), Salix nigra (black willow), and Ulmus rubra * ( slippery elm ) . Somewhat drier sites with a predominance of fine...Dutch Elm Disease. *Ulmus rubra Muhl. SLIPPERY ELM . Common tree in floodplain woods; also occasional in DMP. *Valerianella radiata (L.) Dufr. CORN... elm ), Carya tomentosa (mocker- nut hickory), and Quercus bicolor (swamp white oak). Shrubs and woody vines play a major role in the ecology of these

First insight into the heritable variation of the resistance to infection with the bacteria causing the withering syndrome disease in Haliotis rufescens abalone.

Science.gov (United States)

Brokordt, Katherina; González, Roxana; Farías, William; Winkler, Federico E; Lohrmann, Karin B

2017-11-01

Withering syndrome disease has experienced worldwide spread in the last decade. This fatal disease for abalone is produced by a rickettsia-like organism (WS-RLO), the bacterium "Candidatus Xenohaliotis californiensis". To evaluate the potential of the red abalone (Haliotis rufescens) to improve its resistance to infection by WS-RLO, the additive genetic component in the variation of this trait was estimated. For this, the variation in infection intensity with WS-RLOs and WS-RLOv (phage-infected RLOs) was analyzed in 56 families of full-sibs maintained for three years in a host-parasite cohabitation aquaculture system. A WS-RLO prevalence of 65% was observed in the analysed population; and from the total WS-RLO inclusions 60% were hyperparasited with the phage (WS-RLOv). The decrease in the food ingestion rate was the sole negative effect associated with increasing WS-RLO intensity of infection, suggesting that the high level of WS-RLOv load may have diminished the symptoms of WS disease in the analyzed abalones. The estimated heritabilities were moderate to mid, but significant, varying from 0.21 to 0.23 and 0.36 for WS-RLO and WS-RLOv infections, respectively. This suggests that variation in resistance to infection with WS-RLO may respond to selection in the evaluated red abalone population. Estimated response to selection (G) for the level of infection by WS-RLO indicated that if the 10% of red abalone with the lowest infection level is selected as broodstock, a 90% reduction in the intensity of infection in the progeny can be expected, even with the lowest estimation of heritability (h 2 =0.21). This strong response would be also due to the large phenotypic variance of this trait. Strong positive correlations, both phenotypic and genotypic, were observed between infection intensities with WS-RLO and WS-RLOv, indicating that selection to increase resistance to one of the types of RLOs will affect resistance in the other in the same direction. This is the first

Molecular identification and functional analysis of two variants of myeloid differentiation factor 88 (MyD88) from disk abalone (Haliotis discus discus).

Science.gov (United States)

Priyathilaka, Thanthrige Thiunuwan; Bathige, S D N K; Lee, Seongdo; Lee, Jehee

2018-02-01

Myeloid differentiation factor 88 (MyD88) is a crucial adaptor protein of the Toll-like receptor (TLR)- and interleukin 1 receptor-mediated signaling pathways and is involved in a diverse array of inflammatory responses via NF-κB activation. In the present study, two MyD88 variants were identified from disk abalone (Haliotis discus discus) and designated AbMyD88-2 and AbMyD88-X. The deduced AbMyD88-2 and AbMyD88-X comprised 433 and 354 amino acids with predicted molecular masses of 48.85 kDa and 40.17 kDa, respectively. AbMyD88-2 and AbMyD88-X possessed typical MyD88 domain structural features including an N-terminal death domain (DD) and C-terminal toll interleukin 1 receptor (TIR) domain similar to those in mammals. Expression analysis of AbMyD88-2 and AbMyD88-X mRNA at different early embryonic developmental stages of abalone by qPCR revealed that their constitutive expression at all developmental stages analyzed with the considerably higher values at the 16-cell (AbMyD88-2) and morula stages (AbMyD88-X). In unchallenged disk abalones, AbMyD88-2 was highly expressed in muscles, while AbMyD88-X mRNA was predominantly transcribed in hemocytes. Moreover, AbMyD88-2 and AbMyD88-X mRNA were differentially modulated in abalone hemocytes after a challenge with live bacteria (Vibrio parahaemolyticus, Listeria monocytogenes), virus (viral hemorrhagic septicemia virus), and pathogen-associated molecular patterns (lipopolysaccharides and Poly I:C). Overexpression of AbMyD88-2 and AbMyD88-X in HEK293T cells induced the activation of the NF-κB promoter. AbMyD88-2 and AbMyD88-X involvement in inflammatory responses was characterized by their overexpression in RAW264.7 murine macrophage cells. These results revealed comparatively higher NO (Nitric oxide) production, induction of inflammatory mediator genes (iNOS and COX2), and proinflammatory genes (IL1β, IL6 and TNFα) expression in abalone MyD88s-overexpressing cells than in mock control in the presence or absence of LPS

Post Gliphosate treatments establishment of some grasses

OpenAIRE

Ioan ROTAR; Mariana RUSU; Fl. PRICA

1997-01-01

The sward dominated by Festuca rubra/Agrostis tenuis was treated to reduce the Nardus component and others weed by spraying with Gliphosate. Treatments were applied in the autumn of 1993. In the spring of 1994 a mixture of Phleum pratense, Fesuca rubra, Dactylis glomerata, Trifolium repens and Lotus corniculatus was oversown. Establishment of each species and botanical composition of the pasture were measured over the next three years. Nardus and weed was largely replaced by Phleum/Festuca mi...

Molecular characterization of kappa class glutathione S-transferase from the disk abalone (Haliotis discus discus) and changes in expression following immune and stress challenges.

Science.gov (United States)

Sandamalika, W M Gayashani; Priyathilaka, Thanthrige Thiunuwan; Liyanage, D S; Lee, Sukkyoung; Lim, Han-Kyu; Lee, Jehee

2018-06-01

Glutathione S-transferase (GST; EC 2.5.1.18) isoenzymes represent a complex group of proteins that are involved in phase II detoxification in several organisms. In this study, GST kappa (GSTκ) from the disk abalone (Haliotis discus discus; AbGSTκ) was characterized at both the transcriptional and functional levels to determine its potential capacity to perform as a detoxification agent under conditions of different stress. The predicted AbGSTκ protein consists of 227 amino acids, with a predicted molecular weight of 25.6 kDa and a theoretical isoelectric point (pI) of 7.78. In silico analysis reveals that AbGSTκ is a disulfide bond formation protein A (DsbA), consisting of a thioredoxin domain, GSH binding sites (G-sites), and a catalytic residue. In contrast, no hydrophobic ligand binding site (H-site), or signal peptides, were detected. AbGSTκ showed the highest sequence identity with the orthologue from pufferfish (Takifugu obscurus) (60.0%). In a phylogenetic tree, AbGSTκ clustered closely together with other fish GSTκs, and was evolutionarily distanced from other cytosolic GSTs. The predicted three-dimensional structure clearly demonstrates that the dimer adopts a butterfly-like shape. A tissue distribution analysis revealed that GSTκ was highly expressed in the digestive tract, suggesting it has detoxification ability. Depending on the tissue and time, AbGSTκ showed different expression patterns, and levels of expression, following challenge of the abalone with immune stimulants. Enzyme kinetics of the purified recombinant proteins demonstrated its conjugating ability using 1-Chloro-2,4-dinitrobenzene (CDNB) and glutathione (GSH) as substrates, and suggested it has a low affinity for both substrates. The optimum temperature and pH for the rAbGSTκ GSH: CDNB conjugating activity were found to be 35 °C and pH 8, respectively indicating that the abalone is well adapted to a wide range of environmental conditions. Cibacron blue (100 μM) was

Abalone R&D at AQD

OpenAIRE

Castanos, Milagros T.

1997-01-01

Details are given of the results of research conducted at the SEAFDEC Aquaculture Department on abalone (Haliotis asinina). The following areas are covered: reproductive biology; induced spawning; raising abalone in the hatchery; and, cage culture trials.

A Novel Aldo-Keto Reductase, HdRed, from the Pacific Abalone Haliotis discus hannai, Which Reduces Alginate-derived 4-Deoxy-L-erythro-5-hexoseulose Uronic Acid to 2-Keto-3-deoxy-D-gluconate.

Science.gov (United States)

Mochizuki, Shogo; Nishiyama, Ryuji; Inoue, Akira; Ojima, Takao

2015-12-25

Abalone feeds on brown seaweeds and digests seaweeds' alginate with alginate lyases (EC 4.2.2.3). However, it has been unclear whether the end product of alginate lyases (i.e. unsaturated monouronate-derived 4-deoxy-L-erythro-5-hexoseulose uronic acid (DEH)) is assimilated by abalone itself, because DEH cannot be metabolized via the Embden-Meyerhof pathway of animals. Under these circumstances, we recently noticed the occurrence of an NADPH-dependent reductase, which reduced DEH to 2-keto-3-deoxy-D-gluconate, in hepatopancreas extract of the pacific abalone Haliotis discus hannai. In the present study, we characterized this enzyme to some extent. The DEH reductase, named HdRed in the present study, could be purified from the acetone-dried powder of hepatopancreas by ammonium sulfate fractionation followed by conventional column chromatographies. HdRed showed a single band of ∼ 40 kDa on SDS-PAGE and reduced DEH to 2-keto-3-deoxy-D-gluconate with an optimal temperature and pH at around 50 °C and 7.0, respectively. HdRed exhibited no appreciable activity toward 28 authentic compounds, including aldehyde, aldose, ketose, α-keto-acid, uronic acid, deoxy sugar, sugar alcohol, carboxylic acid, ketone, and ester. The amino acid sequence of 371 residues of HdRed deduced from the cDNA showed 18-60% identities to those of aldo-keto reductase (AKR) superfamily enzymes, such as human aldose reductase, halophilic bacterium reductase, and sea hare norsolorinic acid (a polyketide derivative) reductase-like protein. Catalytic residues and cofactor binding residues known in AKR superfamily enzymes were fairly well conserved in HdRed. Phylogenetic analysis for HdRed and AKR superfamily enzymes indicated that HdRed is an AKR belonging to a novel family. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

A Novel Aldo-Keto Reductase, HdRed, from the Pacific Abalone Haliotis discus hannai, Which Reduces Alginate-derived 4-Deoxy-l-erythro-5-hexoseulose Uronic Acid to 2-Keto-3-deoxy-d-gluconate*

Science.gov (United States)

Mochizuki, Shogo; Nishiyama, Ryuji; Inoue, Akira; Ojima, Takao

2015-01-01

Abalone feeds on brown seaweeds and digests seaweeds' alginate with alginate lyases (EC 4.2.2.3). However, it has been unclear whether the end product of alginate lyases (i.e. unsaturated monouronate-derived 4-deoxy-l-erythro-5-hexoseulose uronic acid (DEH)) is assimilated by abalone itself, because DEH cannot be metabolized via the Embden-Meyerhof pathway of animals. Under these circumstances, we recently noticed the occurrence of an NADPH-dependent reductase, which reduced DEH to 2-keto-3-deoxy-d-gluconate, in hepatopancreas extract of the pacific abalone Haliotis discus hannai. In the present study, we characterized this enzyme to some extent. The DEH reductase, named HdRed in the present study, could be purified from the acetone-dried powder of hepatopancreas by ammonium sulfate fractionation followed by conventional column chromatographies. HdRed showed a single band of ∼40 kDa on SDS-PAGE and reduced DEH to 2-keto-3-deoxy-d-gluconate with an optimal temperature and pH at around 50 °C and 7.0, respectively. HdRed exhibited no appreciable activity toward 28 authentic compounds, including aldehyde, aldose, ketose, α-keto-acid, uronic acid, deoxy sugar, sugar alcohol, carboxylic acid, ketone, and ester. The amino acid sequence of 371 residues of HdRed deduced from the cDNA showed 18–60% identities to those of aldo-keto reductase (AKR) superfamily enzymes, such as human aldose reductase, halophilic bacterium reductase, and sea hare norsolorinic acid (a polyketide derivative) reductase-like protein. Catalytic residues and cofactor binding residues known in AKR superfamily enzymes were fairly well conserved in HdRed. Phylogenetic analysis for HdRed and AKR superfamily enzymes indicated that HdRed is an AKR belonging to a novel family. PMID:26555267

Adoption of parasitic Maculinea alcon caterpillars (Lepidoptera : Lycaenidae) by three Myrmica ant species

DEFF Research Database (Denmark)

Als, Thomas Damm; Nash, David Richard; Boomsma, J. J.

2001-01-01

Maculinea butterflies are parasites of Myrmica ant nests. The Alcon blue, Maculinea alcon, is unusual in that it parasitizes the nests of several Myrmica species, using M. rubra, M. ruginodis and M. scabrinodis as hosts in different parts of Europe. In Denmark it uses M. rubra and M. ruginodis....... alcon from three populations differing in their host use to laboratory nests of all three recorded host ant species collected from each of the M. alcon populations. We measured the attractiveness of the caterpillars to their host ants as the time taken for them to be adopted by each ant colony....... Caterpillars from all populations took longer to be adopted to M. scabrinodis nests than to nests of the other two ant species. Adoption times to M. rubra and M. ruginodis colonies differed: caterpillars from each of the two populations that used a single host species were adopted most quickly by that species...

Field evaluation of in situ remediation of a heavy metal contaminated soil using lime and red-mud

Energy Technology Data Exchange (ETDEWEB)

Gray, C.W. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Dunham, S.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Dennis, P.G. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); Zhao, F.J. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom); McGrath, S.P. [Agriculture and the Environment Division, Rothamsted Research, Harpenden, Herts AL5 2JQ (United Kingdom)]. E-mail: steve.mcgrath@bbsrc.ac.uk

2006-08-15

We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil.

Field evaluation of in situ remediation of a heavy metal contaminated soil using lime and red-mud

International Nuclear Information System (INIS)

Gray, C.W.; Dunham, S.J.; Dennis, P.G.; Zhao, F.J.; McGrath, S.P.

2006-01-01

We evaluated the effectiveness of lime and red mud (by-product of aluminium manufacturing) to reduce metal availability to Festuca rubra and to allow re-vegetation on a highly contaminated brown-field site. Application of both lime and red mud (at 3 or 5%) increased soil pH and decreased metal availability. Festuca rubra failed to establish in the control plots, but grew to a near complete vegetative cover on the amended plots. The most effective treatment in decreasing grass metal concentrations in the first year was 5% red mud, but by year two all amendments were equally effective. In an additional pot experiment, P application in combination with red mud or lime decreased the Pb concentration, but not total uptake of Pb in Festuca rubra compared to red mud alone. The results show that both red mud and lime can be used to remediate a heavily contaminated acid soil to allow re-vegetation. - Red mud was effective in immobilising heavy metals in soil

Molecular identification and functional delineation of a glutathione reductase homolog from disk abalone (Haliotis discus discus): Insights as a potent player in host antioxidant defense.

Science.gov (United States)

Herath, H M L P B; Wickramasinghe, P D S U; Bathige, S D N K; Jayasooriya, R G P T; Kim, Gi-Young; Park, Myoung Ae; Kim, Chul; Lee, Jehee

2017-01-01

Glutathione reductase (GSR) is an enzyme that catalyzes the biochemical conversion of oxidized glutathione (GSSG) into the reduced form (GSH). Since the ratio between the two forms of glutathione (GSH/GSSG) is important for the optimal function of GSH to act as an antioxidant against H 2 O 2 , the contribution of GSR as an enzymatic regulatory agent to maintain the proper ratio is essential. Abalones are marine mollusks that frequently encounter environmental factors that can trigger the overproduction of reactive oxygen species (ROS) such as H 2 O 2 . Therefore, we conducted the current study to reveal the molecular and functional properties of a GSR homolog in the disk abalone, Haliotis discus discus. The identified cDNA sequence (2325 bp) has a 1356 bp long open reading frame (ORF), coding for a 909 bp long amino acid sequence, which harbors a pyridine nucleotide-disulfide oxidoreductase domain (171-246 aa), a pyridine nucleotide-disulfide oxidoreductase dimerization domain, and a NAD(P)(+)-binding Rossmann fold superfamily signature domain. Four functional residues: the FAD binding site, glutathione binding site, NADPH binding motif, and assembly domain were identified to be conserved among the other species. The recombinant abalone GSR (rAbGSR) exhibited detectable activity in a standard glutathione reductase activity assay. The optimum pH and optimal temperature for the reaction were found to be 7.0 and 50 °C, respectively, while the ionic strength of the medium had no effect. The enzymatic reaction was vastly inhibited by Cu +2 and Cd +2 ions. A considerable effect of cellular protection was detected with a disk diffusion assay conducted with rAbGSR. Moreover, an MTT assay and flow cytometry confirmed the significance of the protective role of rAbGSR in cell function. Furthermore, AbGSR was found to be ubiquitously distributed in different types of abalone tissues. AbGSR mRNA expression was significantly upregulated in response to three immune challenges

Dicty_cDB: Contig-U03408-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available ec... 40 0.095 2 ( EF634883 ) Pristionchus pauli small subunit ribosomal protei... 42 0.25 2 ( EH361767 ) NP...Haliotis discus discus ribosomal p... 46 4e-04 EF634883_1( EF634883 |pid:none) Pristionchus pauli small subu

Volatile Constituents of Three Myrsine L. Species from Brazil

Directory of Open Access Journals (Sweden)

Arthur L. Corrêa

2017-01-01

Full Text Available The chemical compositions of the essential oils obtained by hydrodistillation from the aerial parts of Myrsine rubra, Myrsine gardneriana and Myrsine parvifolia and the fruits of Myrsine parvifolia were elucidated by a combination of GC and GC-MS analyses. The main constituents of the native M. parvifolia were caryophyllene oxide (14.4%, β-caryophyllene (12.6% and γ-Muurolene (7.9% of the leaves oil and β-caryophyllene (11.7%, δ-Cadinene (7.1% of the fruit oil. The volatile oil of the endemic M. rubra leaves was dominated by β-caryophyllene (17.2%, γ-Muurolene (11.1%, Germacrene B (10.0%. The essential oil of the native M. gardneriana leaves was characterized by β-caryophyllene (18.0%, γ-Muurolene (8.4%. These three Myrsine species are similar in the dominance of sesquiterpenes. By contrast, monoterpenes were found only in the volatile oil from the fruits of M. parvifolia. To the best of our knowledge, this study is the first report on the volatile constituents of M. rubra, M. gardneriana, M. parvifolia.

Ecophysiological and biochemical traits of three herbaceous plants growing on the disposed coal combustion fly ash of different weathering stage

Directory of Open Access Journals (Sweden)

Gajić Gordana

2013-01-01

Full Text Available The ecophysiological and biochemical traits of Calamagrostis epigejos (Roth. Festuca rubra L. and Oenothera biennis L. growing on two fly ash lagoons of different weathering stage (L1-3 years and L2-11 years of the “Nikola Tesla- A” thermoelectric plant (Obrenovac, Serbia were studied. Species-dependent variations were observed at the L1 lagoon; the greatest vitality (Fv/Fm and Fm/Fo followed by higher photopigment and total phenolic contents were measured in O. biennis in relation to C. epigejos (p<0.001 and F. rubra (p<0.001. At the L2 site, higher vitality was found in O. biennis (p<0.001 and F. rubra (p<0.01 compared to C. epigejos. O. biennis had the highest photosynthetic capacity. The results obtained in this study indicate that all examined species maintained a level of photosynthesis that allowed them to survive and grow under the stressful conditions in ash lagoons, albeit with lower than optimal success. [Projekat Ministarstva nauke Republike Srbije, br. 173018

EPR and IR spectral investigations on some leafy vegetables of Indian origin

Science.gov (United States)

Prasuna, C. P. Lakshmi; Chakradhar, R. P. S.; Rao, J. L.; Gopal, N. O.

2009-09-01

EPR spectral investigations have been carried out on four edible leafy vegetables of India, which are used as dietary component in day to day life. In Rumex vesicarius leaf sample, EPR spectral investigations at different temperatures indicate the presence of anti-ferromagnetically coupled Mn(IV)-Mn(IV) complexes. EPR spectra of Trigonella foenum graecum show the presence of Mn ions in multivalent state and Fe 3+ ions in rhombic symmetry. EPR spectra of Basella rubra indicate the presence of Mn(IV)-O-Mn(IV) type complexes. The EPR spectra of Basella rubra have been studied at different temperatures. It is found that the spin population for the resonance signal at g = 2.06 obeys the Boltzmann distribution law. The EPR spectra of Moringa oliefera leaves show the presence of Mn 2+ ions. Radiation induced changes in free radical of this sample have also been studied. The FT-IR spectra of Basella rubra and Moringa oliefera leaves show the evidences for the protein matrix bands and those corresponding to carboxylic C dbnd O bonds.

Electron/electron acoustic instability

International Nuclear Information System (INIS)

Gary, S.P.

1987-01-01

The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

The distribution of the West Coast rock lobster Jasus lalandii ranges ...

African Journals Online (AJOL)

spamer

Key words: abalone Haliotis midae, Jasus lalandii, predation, sea urchins. * Formerly Marine Biology Research Institute, Zoology Department, University of Cape Town, Rondebosch 7701, South Africa; now. 1/19 Alpha Road, Prospect 5082, South Australia. † Formerly Marine Biology Research Institute; now SARDI Aquatic ...

Population structure and growth of polydorid polychaetes that infest ...

African Journals Online (AJOL)

Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a ...

Exploring basic biochemical constituents in the body tissues of ...

African Journals Online (AJOL)

Feeding regime did not influence susceptibility to mass loss during export. Animal age influenced the biochemical composition and export performance of abalone. Keywords: abalone; aquaculture; feeds; Haliotis midae; live export; mass loss; tissue biochemical constituents. African Journal of Marine Science 2010, 32(1): ...

75 FR 29316 - Marine Mammals; File No. 13599

Science.gov (United States)

2010-05-25

...; fax (301) 713-0376; and Southeast Region, NMFS, 263 13th Avenue South, Saint Petersburg, Florida 33701... the Chief, Permits, Conservation and Education Division, at the address listed above. Comments may... black abalone (Haliotis cracherodii). In compliance with the National Environmental Policy Act of 1969...

Generation and analysis of cDNA library from lipopolysaccharide ...

African Journals Online (AJOL)

These immune-related genes include cytidine deaminase, ferritin, nonmuscle myosin essential light chain, cytochrome c oxidase subunit I, CD63 antigen-like protein and lysosomal-associated transmembrane protein. This study may contribute to the understanding of the immune mechanism of gastropod abalone Haliotis ...

Electronics and electronic systems

CERN Document Server

Olsen, George H

1987-01-01

Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

Electrons, Electronic Publishing, and Electronic Display.

Science.gov (United States)

Brownrigg, Edwin B.; Lynch, Clifford A.

1985-01-01

Provides a perspective on electronic publishing by distinguishing between "Newtonian" publishing and "quantum-mechanical" publishing. Highlights include media and publishing, works delivered through electronic media, electronic publishing and the printed word, management of intellectual property, and recent copyright-law issues…

皱纹盘鲍（Haliotis discus hannai）肠道潜在益生菌的筛选及对幼鲍生长的影响*%SELECTION OF POTENTIAL PROBIOTICS FROM ABALONE INTESTIONAL AND THEIR EFFECTS ON GROWTH OF JUVENILE SMALL ABALONE HALIOTIS DISCUS HANNAI

Institute of Scientific and Technical Information of China (English)

姜海峰; 刘小林; 常亚青; 冷晓飞; 李丹; 王高学

2013-01-01

　　采用体外实验筛选益生菌结合16S rDNA序列分析法,从124株不具有溶血作用的皱纹盘鲍(Haliotis discus hannai)肠道细菌中筛选得到5株潜在益生菌并进行了分子鉴定,进一步对5株潜在益生菌进行了安全性实验及体内饲喂实验。结果表明,2株具有拮抗哈维弧菌和灿烂弧菌能力的潜在益生菌分别被鉴定为Shewanella sp.(WA64)和Shewanella sp.(WA65),一株产海藻酸酶和淀粉酶的潜在益生菌被鉴定为Vibrio sp.(WA51),产蛋白酶潜在益生菌被鉴定为 Bacillus sp.(FA12),产琼脂酶潜在益生菌被鉴定为Tamlana sp.(FA86)；安全性实验表明5株潜在益生菌在107cfu/ml下对皱纹盘鲍没有明显的毒害作用；通过体内饲喂实验发现,潜在益生菌 WA64、WA65的复合作用能够显著提高幼鲍增重率和存活率(P<0.05),并在生产条件下能够明显降低幼鲍的死亡量。经抗生素敏感性实验, WA64菌株对15种抗生素均敏感或中度敏感, WA65菌株仅对庆大霉素和链霉素2种抗生素产生耐药。%Five strains of potential probiotics isolated from 124 non-hemolysis strains of the GI of abalone in vitro were identified by 16S rDNA sequence analysis. In addition, pathogenicity and feeding experiment were conducted. Results show that Strain WA64 and WA65 which exhibit inhibitory effects against Vibrio harveyi, Vibrio splendidus are identified as Shewanella;WA51 produced amylase and alginase is identified as Vibrio;FA123 produced protease is identified as Ba-cillus; FA86 produced agarase is identified as Tamlana. Potential probiotics are safe to abalone under 107cfu/ml. Feeding experiment showed the weight gain ratio and survival rate were significantly increased in treatment supplemented with WA64 and WA65 (P<0.05). Furthermore, the effects of WA64 and WA65 in pilot scale trials show the mortality of juvenile small abalone decreases obviously. Antibiotic sensitivity assays revealed that strain WA64 was sensitive or

Disposition of two names in Almeidea (Rutaceae Disposição de dois nomes em Almeidea (Rutaceae

Directory of Open Access Journals (Sweden)

Milton Groppo

2010-12-01

Full Text Available Examination of type specimens at the P herbarium showed that Almeidea longifolia A. St.-Hil. (Rutaceae is an illegitimate substitute name for A. affinis A. St.-Hil. The latter name is proposed here as a heterotypic synonym of A. rubra A. St.-Hil.O estudo dos tipos nomenclatórios no herbário P mostrou que Almeidea longifolia A. St.-Hil. (Rutaceae é um nome substituto ilegítimo de Almeidea affinis A. St.-Hil., e este último nome é aqui considerado sinônimo heterotípico de A. rubra A. St.-Hil.

Electron-electron Bremsstrahlung for bound target electrons

International Nuclear Information System (INIS)

Haug, E.

2008-01-01

For the process of electron-electron (e-e) Bremsstrahlung the momentum and energy distributions of the recoiling electrons are calculated in the laboratory frame. In order to get the differential cross section and the photon spectrum for target electrons which are bound to an atom, these formulae are multiplied by the incoherent scattering function and numerically integrated over the recoil energy. The effect of atomic binding is most pronounced at low energies of the incident electrons and for target atoms of high atomic numbers. The results are compared to those of previous calculations. (authors)

Polycythemia vera

Science.gov (United States)

Primary polycythemia; Polycythemia rubra vera; Myeloproliferative disorder; Erythremia; Splenomegalic polycythemia; Vaquez's disease; Osler's disease; Polycythemia with chronic cyanosis; Erythrocytosis ...

Nutritional value of the marine invertebrates Anemonia viridis and Haliothis tuberculata and effects on serum cholesterol concentration in ratsopen star

Science.gov (United States)

Gonzalez, M; Caride, B; Lamas, A; Taboada, C

2001-09-01

The purpose of this study was to determine the nutritional value of diets with protein from two marine species (Haliotis tuberculata and Anemonia viridis) as compared to a high-quality protein reference based on casein or casein supplemented with olive oil. We also investigated the effects of these diets on serum lipid levels. Male rats were fed these diets for 23 days. Protein quality indicators (true digestibility, net protein utilization, biological value) were similar to those obtained for casein-based feeds except for lower true digestibility and net protein utilization values for the Anemonia viridis feed. HDL-cholesterol level was significantly higher (p < 0.05) in the groups fed marine species or casein supplemented with olive oil than in the casein group. Total-cholesterol level was higher in the group fed Haliotis tuberculata fed than in the other groups. These results suggest that these marine species are a good protein source, and that they may have positive effects on serum cholesterol level.

Interplay between electron-phonon and electron-electron interactions

International Nuclear Information System (INIS)

Roesch, O.; Gunnarsson, O.; Han, J.E.; Crespi, V.H.

2005-01-01

We discuss the interplay between electron-electron and electron-phonon interactions for alkali-doped fullerides and high temperature superconductors. Due to the similarity of the electron and phonon energy scales, retardation effects are small for fullerides. This raises questions about the origin of superconductivity, since retardation effects are believed to be crucial for reducing effects of the Coulomb repulsion in conventional superconductors. We demonstrate that by treating the electron-electron and electron-phonon interactions on an equal footing, superconductivity can be understood in terms of a local pairing. The Jahn-Teller character of the important phonons in fullerides plays a crucial role for this result. To describe effects of phonons in cuprates, we derive a t-J model with phonons from the three-band model. Using exact diagonalization for small clusters, we find that the anomalous softening of the half-breathing phonon as well as its doping dependence can be explained. By comparing the solution of the t-J model with the Hartree-Fock approximation for the three-band model, we address results obtained in the local-density approximation for cuprates. We find that genuine many-body results, due to the interplay between the electron-electron and electron-phonon interactions, play an important role for the the results in the t-J model. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Recobrimentos e períodos de armazenamento na conservação pós-colheita de estacas de cordiline (Cordyline rubra Hügel

Directory of Open Access Journals (Sweden)

Nelson Mamoru Sakamoto

2011-10-01

Full Text Available O Brasil possui grande potencial exportador de flores e plantas ornamentais, e o emprego de técnicas simples de armazenamento poderia viabilizar o transporte por modais que não o aéreo, reduzindo custos, podendo prolongar a vida útil dos produtos. Este trabalho compara cinco tipos de recobrimento em estacas de Cordyline rubra Hügel (película amilácea, pasta de parafina no ápice, pasta de parafina no ápice e vermiculita umedecida na base, saco plástico ou sem recobrimento e diferentes períodos de armazenamento (30, 60, 90 ou 120 dias, a fim de reduzir sua atividade biológica, perda de água e ataque de patógenos. Foi escolhida esta espécie por ser muito apreciada como planta ornamental pela beleza de suas folhas e exportada na forma de estacas de diferentes tamanhos. O experimento foi conduzido nas dependências do Departamento de Produção Vegetal da Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, no município de Piracicaba, Estado de São Paulo. Foram utilizadas 300 estacas com 30 cm de comprimento por 3 cm de diâmetro. Cada tratamento foi composto por 15 estacas pré-tratadas (tipos de recobrimento, submetidas a períodos de armazenamento (30, 60, 90 ou 120 dias sob refrigeração e temperatura ambiente, totalizando 60 estacas. Após o armazenamento, foram cortados 3 cm da base de cada estaca, em seguida, tratadas com ácido indolbutírico a 10.000 mg/L e colocadas em leito de enraizamento de areia grossa. Após 90 dias, foram avaliados os seguintes parâmetros: porcentagem de desenvolvimento, número e massa fresca e seca de brotos e raízes. Observou-se que os menores períodos de armazenamento proporcionam melhor desenvolvimento das estacas. Os tipos de recobrimento que melhor conservaram as estacas, em ordem decrescente de resultados, foram o saco plástico, parafina no ápice e vermiculita umedecida na base, parafina no ápice, película de amido e sem recobrimento. Conclui-se que o m

Crystal orientations in nacreous layers of organic-inorganic biocomposites

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Woo, E-mail: jacklee@kaist.ac.kr [Department of Chemical and Biomolecular Engineering, KAIST, Daejeon (Korea, Republic of)

2009-09-15

Abalone shell comprises a bio-composite material, combining the properties of inorganic calcite intergrown with organic nacre. This paper reports about the microstructure of this composite. By examining the Kikuchi patterns obtained for nacre (Haliotis discus hannai) using transmission electron microscopy, we have shown that the tiles within nacre have specific orientations. The stereographic projection spheres for the tiles of nacre can be divided into two main types, namely a right oriented region and a left oriented region with respect to the c axis as a reference plane (001). The cluster character of nacre can be explained in terms of the growth mechanism of the 'Christmas tree' pattern. The orientation of the c-axis in the nacreous layer is elucidated for the first time. We demonstrate the use of the soluble protein obtained from the tiles of nacre in in vitro calcium carbonate crystallization.

Crystal orientations in nacreous layers of organic-inorganic biocomposites

International Nuclear Information System (INIS)

Lee, Seung Woo

2009-01-01

Abalone shell comprises a bio-composite material, combining the properties of inorganic calcite intergrown with organic nacre. This paper reports about the microstructure of this composite. By examining the Kikuchi patterns obtained for nacre (Haliotis discus hannai) using transmission electron microscopy, we have shown that the tiles within nacre have specific orientations. The stereographic projection spheres for the tiles of nacre can be divided into two main types, namely a right oriented region and a left oriented region with respect to the c axis as a reference plane (001). The cluster character of nacre can be explained in terms of the growth mechanism of the 'Christmas tree' pattern. The orientation of the c-axis in the nacreous layer is elucidated for the first time. We demonstrate the use of the soluble protein obtained from the tiles of nacre in in vitro calcium carbonate crystallization.

Electronic emission and electron guns

International Nuclear Information System (INIS)

Roy, Amitava

2010-01-01

This paper reviews the process of electron emission from metal surface. Although electrons move freely in conductors like metals, they normally do not leave the metal without some manipulation. In fact, heating and bombardment are the two primary ways in which electrons are emitted through the use of a heating element behind the cathode (termed thermionic emission) or as a result of bombardment with a beam of electrons, ions, or metastable atoms (termed secondary emission). Another important emission mechanism called Explosive Electron Emission (EEE) is also often used in various High Voltage Pulse Power Systems to generate very high current (few hundreds of kA) pulsed electron beams. The electron gun is the device in that it shoots off a continuous (or pulsed) stream of electrons. A brief idea about the evolution of the electron gun components and their basis of functioning are also discussed. (author)

Towards adaptive approaches to management of the South African ...

African Journals Online (AJOL)

The South African abalone Haliotis midae resource is widely perceived as being under threat of overexploitation as a result of increased poaching. In this paper, reservations are expressed about using catch per unit effort as the sole index of abundance when assessing this fishery, particularly because of the highly ...

Born-Oppenheimer Dynamics, Electronic Friction, and the Inclusion of Electron-Electron Interactions

Science.gov (United States)

Dou, Wenjie; Miao, Gaohan; Subotnik, Joseph E.

2017-07-01

We present a universal expression for the electronic friction as felt by a set of classical nuclear degrees of freedom (DOFs) coupled to a manifold of quantum electronic DOFs; no assumptions are made regarding the nature of the electronic Hamiltonian and electron-electron repulsions are allowed. Our derivation is based on a quantum-classical Liouville equation for the coupled electronic-nuclear motion, followed by an adiabatic approximation whereby electronic transitions are assumed to equilibrate faster than nuclear movement. The resulting form of friction is completely general, but does reduce to previously published expressions for the quadratic Hamiltonian (i.e., Hamiltonians without electronic correlation). At equilibrium, the second fluctuation-dissipation theorem is satisfied and the frictional matrix is symmetric. To demonstrate the importance of electron-electron correlation, we study electronic friction within the Anderson-Holstein model, where a proper treatment of electron-electron interactions shows signatures of a Kondo resonance and a mean-field treatment is completely inadequate.

Determining inhibition effects of some aromatic compounds on peroxidase enzyme purified from white and red cabbage

Energy Technology Data Exchange (ETDEWEB)

Öztekin, Aykut, E-mail: aoztekin@agri.edu.tr [Ataturk University, Science Faculty, Department of Chemistry, 25240-Erzurum (Turkey); Agri Ibrahim Cecen University Faculty of Arts and Sciences, Department of Chemistry, 04100-Agri (Turkey); Almaz, Züleyha, E-mail: zturkoglu-2344@hotmail.com [Ataturk University, Science Faculty, Department of Chemistry, 25240-Erzurum (Turkey); Mus Alparslan University Faculty of Sciences, Department of Moleculer Biology, 49250-Mus (Turkey); Özdemir, Hasan, E-mail: hozdemir@atauni.edu.tr [Ataturk University, Science Faculty, Department of Chemistry, 25240-Erzurum (Turkey)

2016-04-18

Peroxidases (E.C.1.11.1.7) catalyze the one electron oxidation of wide range of substrates. They are used in synthesis reaction, removal of peroxide from industrial wastes, clinical biochemistry and immunoassays. In this study, the white cabbage (Brassica Oleracea var. capitata f. alba) and red cabbage (Brassica oleracea L. var. capitata f. rubra) peroxidase enzymes were purified for investigation of inhibitory effect of some aromatic compounds on these enzymes. IC{sub 50} values and Ki constants were calculated for the molecules of 6-Amino nicotinic hydrazide, 6-Amino-5-bromo nicotinic hydrazide, 2-Amino-5-hydroxy benzohydrazide, 4-Amino-3-hydroxy benzohydrazide on purified enzymes and inhibition type of these molecules were determined. (This research was supported by Ataturk University. Project Number: BAP-2015/98).

Determining inhibition effects of some aromatic compounds on peroxidase enzyme purified from white and red cabbage

Science.gov (United States)

Öztekin, Aykut; Almaz, Züleyha; Özdemir, Hasan

2016-04-01

Peroxidases (E.C.1.11.1.7) catalyze the one electron oxidation of wide range of substrates. They are used in synthesis reaction, removal of peroxide from industrial wastes, clinical biochemistry and immunoassays. In this study, the white cabbage (Brassica Oleracea var. capitata f. alba) and red cabbage (Brassica oleracea L. var. capitata f. rubra) peroxidase enzymes were purified for investigation of inhibitory effect of some aromatic compounds on these enzymes. IC50 values and Ki constants were calculated for the molecules of 6-Amino nicotinic hydrazide, 6-Amino-5-bromo nicotinic hydrazide, 2-Amino-5-hydroxy benzohydrazide, 4-Amino-3-hydroxy benzohydrazide on purified enzymes and inhibition type of these molecules were determined. (This research was supported by Ataturk University. Project Number: BAP-2015/98).

Determining inhibition effects of some aromatic compounds on peroxidase enzyme purified from white and red cabbage

International Nuclear Information System (INIS)

Öztekin, Aykut; Almaz, Züleyha; Özdemir, Hasan

2016-01-01

Peroxidases (E.C.1.11.1.7) catalyze the one electron oxidation of wide range of substrates. They are used in synthesis reaction, removal of peroxide from industrial wastes, clinical biochemistry and immunoassays. In this study, the white cabbage (Brassica Oleracea var. capitata f. alba) and red cabbage (Brassica oleracea L. var. capitata f. rubra) peroxidase enzymes were purified for investigation of inhibitory effect of some aromatic compounds on these enzymes. IC_5_0 values and Ki constants were calculated for the molecules of 6-Amino nicotinic hydrazide, 6-Amino-5-bromo nicotinic hydrazide, 2-Amino-5-hydroxy benzohydrazide, 4-Amino-3-hydroxy benzohydrazide on purified enzymes and inhibition type of these molecules were determined. (This research was supported by Ataturk University. Project Number: BAP-2015/98).

Reprint of: Growth of nacre in abalone: Seasonal and feeding effects

Energy Technology Data Exchange (ETDEWEB)

Lopez, M.I., E-mail: mil032@ucsd.edu; Chen, P.Y.; McKittrick, J.; Meyers, M.A.

2011-05-10

The processes of aggregation of mineral and organic materials to the growing surfaces in red abalone (Haliotis rufescens) are analyzed. The flat pearl implantation method is used to observe the transient stages of calcium carbonate deposition, the structure of the organic interlayer, and the steady-state growth of aragonite tiles. The morphology of the organic interlayer is characterized by scanning electron microscopy. These results enable a realistic depiction of the formation of the terraced cones that comprise the principal biomineralization mechanism in this gastropod. In all cases, the growth initiated through spherulites, followed by tile formation. The transient stage with spherulitic formation was shorter at higher temperature; this is indicative of a greater activity of the animal at 21 deg. C. The growth rate in a normally fed gastropod was found to be higher compared with one provided with limited food. The effect of water temperature (seasonal) was also established, with growth proceeding faster in the summer (T {approx} 21 deg. C) than in winter (15 deg. C). The structures of the organic interlayer and of the epithelium are revealed by scanning electron microscopy.

Growth of nacre in abalone: Seasonal and feeding effects

International Nuclear Information System (INIS)

Lopez, M.I.; Chen, P.Y.; McKittrick, J.; Meyers, M.A.

2011-01-01

The processes of aggregation of mineral and organic materials to the growing surfaces in red abalone (Haliotis rufescens) are analyzed. The flat pearl implantation method is used to observe the transient stages of calcium carbonate deposition, the structure of the organic interlayer, and the steady-state growth of aragonite tiles. The morphology of the organic interlayer is characterized by scanning electron microscopy. These results enable a realistic depiction of the formation of the terraced cones that comprise the principal biomineralization mechanism in this gastropod. In all cases, the growth initiated through spherulites, followed by tile formation. The transient stage with spherulitic formation was shorter at higher temperature; this is indicative of a greater activity of the animal at 21 deg. C. The growth rate in a normally fed gastropod was found to be higher compared with one provided with limited food. The effect of water temperature (seasonal) was also established, with growth proceeding faster in the summer (T ∼ 21 deg. C) than in winter (15 deg. C). The structures of the organic interlayer and of the epithelium are revealed by scanning electron microscopy.

Reprint of: Growth of nacre in abalone: Seasonal and feeding effects

International Nuclear Information System (INIS)

Lopez, M.I.; Chen, P.Y.; McKittrick, J.; Meyers, M.A.

2011-01-01

The processes of aggregation of mineral and organic materials to the growing surfaces in red abalone (Haliotis rufescens) are analyzed. The flat pearl implantation method is used to observe the transient stages of calcium carbonate deposition, the structure of the organic interlayer, and the steady-state growth of aragonite tiles. The morphology of the organic interlayer is characterized by scanning electron microscopy. These results enable a realistic depiction of the formation of the terraced cones that comprise the principal biomineralization mechanism in this gastropod. In all cases, the growth initiated through spherulites, followed by tile formation. The transient stage with spherulitic formation was shorter at higher temperature; this is indicative of a greater activity of the animal at 21 deg. C. The growth rate in a normally fed gastropod was found to be higher compared with one provided with limited food. The effect of water temperature (seasonal) was also established, with growth proceeding faster in the summer (T ∼ 21 deg. C) than in winter (15 deg. C). The structures of the organic interlayer and of the epithelium are revealed by scanning electron microscopy.

Growth of nacre in abalone: Seasonal and feeding effects

Energy Technology Data Exchange (ETDEWEB)

Lopez, M.I., E-mail: mil032@ucsd.edu; Chen, P.Y.; McKittrick, J.; Meyers, M.A.

2011-03-12

The processes of aggregation of mineral and organic materials to the growing surfaces in red abalone (Haliotis rufescens) are analyzed. The flat pearl implantation method is used to observe the transient stages of calcium carbonate deposition, the structure of the organic interlayer, and the steady-state growth of aragonite tiles. The morphology of the organic interlayer is characterized by scanning electron microscopy. These results enable a realistic depiction of the formation of the terraced cones that comprise the principal biomineralization mechanism in this gastropod. In all cases, the growth initiated through spherulites, followed by tile formation. The transient stage with spherulitic formation was shorter at higher temperature; this is indicative of a greater activity of the animal at 21 deg. C. The growth rate in a normally fed gastropod was found to be higher compared with one provided with limited food. The effect of water temperature (seasonal) was also established, with growth proceeding faster in the summer (T {approx} 21 deg. C) than in winter (15 deg. C). The structures of the organic interlayer and of the epithelium are revealed by scanning electron microscopy.

A decade of illegal fishing in Table Mountain National Park (2000 ...

African Journals Online (AJOL)

Illegal fishing activities are reported to be on the increase in South Africa, including in its marine protected areas (MPAs). Research is presented on the nature and the scale of illegal fishing in Table Mountain National Park (TMNP) by analysing the numbers of abalone Haliotis midae and West Coast rock lobster Jasus ...

Integrated culture of silver kob Argyrosomus inodorus and ...

African Journals Online (AJOL)

South African abalone Haliotis midae farms utilise large volumes of seawater (c. 500–1 500 l s–1) and produce relatively dilute effluents that are potentially suitable for the integrated culture of other species. To test this hypothesis, a marine finfish, silver kob Argyrosomus inodorus, and a detritivorous polychaete, bloodworm ...

Effect of nitrogen fertilization, grass species and cultivar on sod production on Valkeasuo peat bog - a case study

Directory of Open Access Journals (Sweden)

Perttu Virkajärvi

1997-09-01

Full Text Available As part of a research project concerning the agricultural utilization of cut-away peat bogs, a sod production experiment was conducted at Valkeasuo, Tohmajärvi, in 1990-1993. The aim of the experiment was to study the effect of nitrogen and choice of cultivar on sod production and sod quality on peat bogs. The N fertilization rates were 50, 100 and 150kg ha-1. The Poa pratensis cultivars were ‘Conni’, ‘Cynthia’, ‘Haga’ and ‘Julia’, the Festuca rubra cultivars were ‘Center’, ‘Juliska’, ‘Koket’ and ‘Näpsä’ and the Agrostis capillaris cultivar was ‘Rasti’. Two mixtures of P. pratensis/F. rubra and one of A. capillaris/F. rubra imitated commercial sod products. Increasing of N fertilization from 50 kg up to 150 kg ha-1 a had positive effect on general the quality of sod as well as on the green cover before and after transplanting. It increased the thatch formation. The positive effect of N on the number of tillers and green cover in the year following transplanting was dependent on the species and the cultivar. Species and cultivar affected all measured variables excluding thatch formation. Generally, the P. pratensis cultivars tested suited better for sod production than cultivars of F. rubra, but there were clear differences between cultivars within species as well. Although the soil was infertile, the contents of Ca, K, Mg, P, Cu, Fe, Mn, Mo and Zn in the herbage samples were within normal range. The botanical purity was high, which supports the hypothesis that the absence of seed bank of weeds on peat bogs immediately after harvesting the peat can be utilized.

Study of pathophysiology of pulmonary circulation in polycythemia using scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Fujii, Tadashige; Tanaka, Masao; Takeda, Tadashi; Kawashima, Akira; Kubo, Keiji; Kobayashi, Toshio; Handa, Kenjiro; Yoshimura, Kazuhiko (Shinshu Univ., Matsumoto, Nagano (Japan). Faculty of Medicine)

1993-09-01

In order to evaluate the pathophysiology of pulmonary circulation in polycythemia, Tl-201 myocardial scintigraphy and perfusion lung scintigraphy with 99m-Tc-MAA were performed in 19 cases of polycythemia including polycythemia rubra vera and in 11 cases of secondary polycythemia due to pulmonary diseases. Tl-201 lung uptake, right ventricular visualization and pulmonary perfusion impairment were studied. In the 19 cases, Tl-201 lung uptake was observed in all cases and 54.5% of them showed moderate lung uptake. The grade of right ventricular visualization was moderate in one case and slight in 16 cases; right ventricular hypertrophy was shown in 89.5% of all cases by Tl-201 scintigraphy, only one of which showed right ventricular hypertrophy on electrocardiography. Abnormalities of lung perfusion consisted of scattered small areas of hypoperfusion in 36.8%, peripheral hypoperfusion in 78.9% and uneven distribution of pulmonary perfusion in 94.7%. The degree of hypoperfusion was slightly related to decrease in FEV 1.0%, V25 and PaO[sub 2] and increase in circulating blood volume and peripheral red blood cell counts. Abnormalities of pulmonary function consisted of increased RV/TLC in 50.0%, increased CV/VC in 35.7% and decreased V25 in 36.8%. Arterial blood gases showed hypoxemia in 57.1%, the degree of which was slightly related to increase in RV/TLC and CV/VC and decrease in V25. Cases of secondary polycythemia due to pulmonary diseases showed more marked right ventricular visualization, pulmonary perfusion impairment and abnormalities of various kinds of pulmonary function than polycythemia rubra vera cases. It seems to be important to evaluate the pathophysiology of pulmonary circulation in polycythemia rubra vera as well as secondary polycythemia due to cardio-pulmonary diseases, because pulmonary perfusion impairment and moderate right ventricular visualization are observed frequently in polycythemia rubra vera. (author).

Study of pathophysiology of pulmonary circulation in polycythemia using scintigraphy

International Nuclear Information System (INIS)

Fujii, Tadashige; Tanaka, Masao; Takeda, Tadashi; Kawashima, Akira; Kubo, Keiji; Kobayashi, Toshio; Handa, Kenjiro; Yoshimura, Kazuhiko

1993-01-01

In order to evaluate the pathophysiology of pulmonary circulation in polycythemia, Tl-201 myocardial scintigraphy and perfusion lung scintigraphy with 99m-Tc-MAA were performed in 19 cases of polycythemia including polycythemia rubra vera and in 11 cases of secondary polycythemia due to pulmonary diseases. Tl-201 lung uptake, right ventricular visualization and pulmonary perfusion impairment were studied. In the 19 cases, Tl-201 lung uptake was observed in all cases and 54.5% of them showed moderate lung uptake. The grade of right ventricular visualization was moderate in one case and slight in 16 cases; right ventricular hypertrophy was shown in 89.5% of all cases by Tl-201 scintigraphy, only one of which showed right ventricular hypertrophy on electrocardiography. Abnormalities of lung perfusion consisted of scattered small areas of hypoperfusion in 36.8%, peripheral hypoperfusion in 78.9% and uneven distribution of pulmonary perfusion in 94.7%. The degree of hypoperfusion was slightly related to decrease in FEV 1.0%, V25 and PaO 2 and increase in circulating blood volume and peripheral red blood cell counts. Abnormalities of pulmonary function consisted of increased RV/TLC in 50.0%, increased CV/VC in 35.7% and decreased V25 in 36.8%. Arterial blood gases showed hypoxemia in 57.1%, the degree of which was slightly related to increase in RV/TLC and CV/VC and decrease in V25. Cases of secondary polycythemia due to pulmonary diseases showed more marked right ventricular visualization, pulmonary perfusion impairment and abnormalities of various kinds of pulmonary function than polycythemia rubra vera cases. It seems to be important to evaluate the pathophysiology of pulmonary circulation in polycythemia rubra vera as well as secondary polycythemia due to cardio-pulmonary diseases, because pulmonary perfusion impairment and moderate right ventricular visualization are observed frequently in polycythemia rubra vera. (author)

A Rapid and Efficient Screening Method for Antibacterial Compound-Producing Bacteria.

Science.gov (United States)

Hettiarachchi, Sachithra; Lee, Su-Jin; Lee, Youngdeuk; Kwon, Young-Kyung; De Zoysa, Mahanama; Moon, Song; Jo, Eunyoung; Kim, Taeho; Kang, Do-Hyung; Heo, Soo-Jin; Oh, Chulhong

2017-08-28

Antibacterial compounds are widely used in the treatment of human and animal diseases. The overuse of antibiotics has led to a rapid rise in the prevalence of drug-resistant bacteria, making the development of new antibacterial compounds essential. This study focused on developing a fast and easy method for identifying marine bacteria that produce antibiotic compounds. Eight randomly selected marine target bacterial species ( Agrococcus terreus, Bacillus algicola, Mesoflavibacter zeaxanthinifaciens, Pseudoalteromonas flavipulchra, P. peptidolytica, P. piscicida, P. rubra , and Zunongwangia atlantica ) were tested for production of antibacterial compounds against four strains of test bacteria ( B. cereus, B. subtilis, Halomonas smyrnensis , and Vibrio alginolyticus ). Colony picking was used as the primary screening method. Clear zones were observed around colonies of P. flavipulchra, P. peptidolytica, P. piscicida , and P. rubra tested against B. cereus, B. subtilis , and H. smyrnensis . The efficiency of colony scraping and broth culture methods for antimicrobial compound extraction was also compared using a disk diffusion assay. P. peptidolytica, P. piscicida , and P. rubra showed antagonistic activity against H. smyrnensis, B. cereus , and B. subtilis , respectively, only in the colony scraping method. Our results show that colony picking and colony scraping are effective, quick, and easy methods of screening for antibacterial compound-producing bacteria.

Effective electron-electron and electron-phonon interactions in the Hubbard-Holstein model

International Nuclear Information System (INIS)

Aprea, G.; Di Castro, C.; Grilli, M. . E-mail marco.grilli@roma1.infn.it; Lorenzana, J.

2006-01-01

We investigate the interplay between the electron-electron and the electron-phonon interaction in the Hubbard-Holstein model. We implement the flow-equation method to investigate within this model the effect of correlation on the electron-phonon effective coupling and, conversely, the effect of phonons in the effective electron-electron interaction. Using this technique we obtain analytical momentum-dependent expressions for the effective couplings and we study their behavior for different physical regimes. In agreement with other works on this subject, we find that the electron-electron attraction mediated by phonons in the presence of Hubbard repulsion is peaked at low transferred momenta. The role of the characteristic energies involved is also analyzed

Electron-electron coincidence spectroscopies at surfaces

International Nuclear Information System (INIS)

Stefani, G.; Iacobucci, S.; Ruocco, A.; Gotter, R.

2002-01-01

In the past 20 years, a steadily increasing number of electron-electron coincidence experiments on atoms and molecules have contributed to a deeper understanding of electron-electron correlation effects. In more recent years this technique has been extended to the study of solid surfaces. This class of one photon IN two electrons OUT experiments will be discussed with an emphasis on grazing incidence geometry, that is expected to be particularly suited for studying surfaces. The crucial question of which is the dominant mechanism that leads to ejection of pairs of electron from the surface will be addressed. It will be shown that, depending on the kinematics chosen, the correlated behaviour of the pairs of electrons detected might be singled out from independent particle one

Common indoor and outdoor aero-allergens in South Africa

African Journals Online (AJOL)

Aero-allergens in South Africa that are also encountered around the world are listed in Table I. In addition to this wide range of common aero-allergens, South Africans are also exposed to a full range of food allergens, some of which, e.g. perlemoen (Haliotis midae) and other seafood allergens, are unique to this region.

Short Communication Effects of heavy metals on the development ...

African Journals Online (AJOL)

Despite a growing abalone Haliotis midae industry in South Africa, few studies have measured the effects of heavy metals on larval survival and growth in the face of recent increases in marine pollution. The aim of this study was to quantify the effect of copper on survival and zinc on development of H. midae larvae. Larvae ...

Electron distribution function in electron-beam-excited plasmas

International Nuclear Information System (INIS)

Brau, C.A.

1976-01-01

In monatomic plasmas excited by high-intensity relativistic electron beams, the electron secondary distribution function is dominated by elastic electron-electron collisions at low electron energies and by inelastic electron-atom collisions at high electron energies (above the excitation threshold). Under these conditions, the total rate of excitation by inelastic collisions is limited by the rate at which electron-electron collisions relax the distribution function in the neighborhood of the excitation threshold. To describe this effect quantitatively, an approximate analytic solution of the electron Boltzmann equation is obtained, including both electron-electron and inelastic collisions. The result provides a simple formula for the total rate of excitation

Hard electronics; Hard electronics

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

76 FR 66954 - Endangered Species; Receipt of Applications for Permit

Science.gov (United States)

2011-10-28

...). black lemur (Eulemur macaco). brown lemur (Eulemur fulvus). black and white ruffed lemur (Varecia...). black and white ruffed lemur (Varecia variagata). red ruffed lemur (Varecia rubra). black lemur (Eulemur...

Electron radiography

Science.gov (United States)

Merrill, Frank E.; Morris, Christopher

2005-05-17

A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

Effect of activated sludge culture conditions on Waxberry wastewater

Science.gov (United States)

Shi, Liang; He, Lingfeng; Zhang, Yongli

2018-03-01

Treated activated sludge is suitable for the treatment of wastewater. Biochemical method is used to treat the wastewater, and the influence of time on the COD index is investigated. The results showed that time had a significant effect on COD, and then affected the performance of activated sludge. Under different time, according to the order of time from short to long, COD decreases in turn. Under the action of activated sludge, the degradation of myrica rubra wastewater samples, after 25 h aeration for 96 h, the effect is better. Under this condition, the COD value was reduced at 72 mg/L, and the COD removal efficiency of myrica rubra wastewater was up to 93.39 %, and reached the two level discharge standard of municipal wastewater treatment.

Electron transfer from electronic excited states to sub-vacuum electron traps in amorphous ice

International Nuclear Information System (INIS)

Vichnevetski, E.; Bass, A.D.; Sanche, L.

2000-01-01

We investigate the electron stimulated yield of electronically excited argon atoms (Ar * ) from monolayer quantities of Ar deposited onto thin films of amorphous ice. Two peaks of narrow width ( - electron-exciton complex into exciton states, by the transfer of an electron into a sub-vacuum electron state within the ice film. However, the 10.7 eV feature is shifted to lower energy since electron attachment to Ar occurs within small pores of amorphous ice. In this case, the excess electron is transferred into an electron trap below the conduction band of the ice layer

Monte Carlo study of electron relaxation in graphene with spin polarized, degenerate electron gas in presence of electron-electron scattering

Science.gov (United States)

Borowik, Piotr; Thobel, Jean-Luc; Adamowicz, Leszek

2017-12-01

The Monte Carlo simulation method is applied to study the relaxation of excited electrons in monolayer graphene. The presence of spin polarized background electrons population, with density corresponding to highly degenerate conditions is assumed. Formulas of electron-electron scattering rates, which properly account for electrons presence in two energetically degenerate, inequivalent valleys in this material are presented. The electron relaxation process can be divided into two phases: thermalization and cooling, which can be clearly distinguished when examining the standard deviation of electron energy distribution. The influence of the exchange effect in interactions between electrons with parallel spins is shown to be important only in transient conditions, especially during the thermalization phase.

An invasive slug exploits an ant-seed dispersal mutualism.

Science.gov (United States)

Meadley Dunphy, Shannon A; Prior, Kirsten M; Frederickson, Megan E

2016-05-01

Plant-animal mutualisms, such as seed dispersal, are often vulnerable to disruption by invasive species. Here, we show for the first time how a non-ant invasive species negatively affects seed dispersal by ants. We examined the effects of several animal species that co-occur in a temperate deciduous forest-including native and invasive seed-dispersing ants (Aphaenogaster rudis and Myrmica rubra, respectively), an invasive slug (Arion subfuscus), and native rodents-on a native myrmecochorous plant, Asarum canadense. We experimentally manipulated ant, slug, and rodent access to seed depots and measured seed removal. We also video-recorded depots to determine which other taxa interact with seeds. We found that A. rudis was the main disperser of seeds and that A. subfuscus consumed elaiosomes without dispersing seeds. Rodent visitation was rare, and rodent exclusion had no significant effect on seed or elaiosome removal. We then used data obtained from laboratory and field mesocosm experiments to determine how elaiosome robbing by A. subfuscus affects seed dispersal by A. rudis and M. rubra. We found that elaiosome robbing by slugs reduced seed dispersal by ants, especially in mesocosms with A. rudis, which picks up seeds more slowly than M. rubra. Taken together, our results show that elaiosome robbing by an invasive slug reduces seed dispersal by ants, suggesting that invasive slugs can have profound negative effects on seed dispersal mutualisms.

Electron attachment cross sections obtained from electron attachment spectroscopy

International Nuclear Information System (INIS)

Popp, P.; Baumbach, J.I.; Leonhardt, J.W.; Mothes, S.

1988-01-01

Electron capture detectors have a high sensitivity for substances with high thermal electron attachment cross sections. The electron attachment spectroscopy makes it possible to change the mean electron energy in such a way that the maximum for dissociative electron attachment is reached. Thus, best operation modes of the detection system as well as significant dependencies of electron attachment coefficients are available. Cross sections for electron attachment as a function of the electron energy are obtained with the knowledge of electron energy distribution functions from Boltzmann equation analysis by a special computer code. A disadvantage of this electron attachment spectroscopy is the superposition of space charge effects due to the decrease of the electron drift velocity with increasing mean electron energy. These influences are discussed. (author)

Electron beam effects in auger electron spectroscopy and scanning electron microscopy

International Nuclear Information System (INIS)

Fontaine, J.M.; Duraud, J.P.; Le Gressus, C.

1979-01-01

Electron beam effects on Si(100) and 5% Fe/Cr alloy samples have been studied by measurements of the secondary electron yield delta, determination of the surface composition by Auger electron spectroscopy and imaging with scanning electron microscopy. Variations of delta as a function of the accelerating voltage Esub(p) (0.5 -9 Torr has no effect on technological samples covered with their reaction layers; the sensitivities to the beam depend rather on the earlier mechanical, thermal and chemical treatment of the surfaces. (author)

The effect of electron-electron interaction induced dephasing on electronic transport in graphene nanoribbons

Energy Technology Data Exchange (ETDEWEB)

Kahnoj, Sina Soleimani; Touski, Shoeib Babaee [School of Electrical and Computer Engineering, University of Tehran, P.O. Box 14395-515, Tehran (Iran, Islamic Republic of); Pourfath, Mahdi, E-mail: pourfath@ut.ac.ir, E-mail: pourfath@iue.tuwien.ac.at [School of Electrical and Computer Engineering, University of Tehran, P.O. Box 14395-515, Tehran (Iran, Islamic Republic of); Institute for Microelectronics, TU Wien, Gusshausstrasse 27–29/E360, 1040 Vienna (Austria)

2014-09-08

The effect of dephasing induced by electron-electron interaction on electronic transport in graphene nanoribbons is theoretically investigated. In the presence of disorder in graphene nanoribbons, wavefunction of electrons can set up standing waves along the channel and the conductance exponentially decreases with the ribbon's length. Employing the non-equilibrium Green's function formalism along with an accurate model for describing the dephasing induced by electron-electron interaction, we show that this kind of interaction prevents localization and transport of electrons remains in the diffusive regime where the conductance is inversely proportional to the ribbon's length.

Electron Beam Generation in Tevatron Electron Lenses

International Nuclear Information System (INIS)

Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.

2006-01-01

New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices

Electron beam generation in Tevatron electron lenses

International Nuclear Information System (INIS)

Kamerdzhiev, V.; Kuznetsov, G.; Shiltsev, V.; Solyak, N.; Tiunov, M.

2006-01-01

New type of high perveance electron guns with convex cathode has been developed. Three guns described in this article are built to provide transverse electron current density distributions needed for Electron Lenses for beam-beam compensation in the Tevatron collider. The current distribution can be controlled either by the gun geometry or by voltage on a special control electrode located near cathode. We present the designs of the guns and report results of beam measurements on the test bench. Because of their high current density and low transverse temperature of electrons, electron guns of this type can be used in electron cooling and beam-beam compensation devices

Dietary effect of silage type and combination with camelina seed on ...

African Journals Online (AJOL)

Daniel

2015-02-07

Feb 7, 2015 ... 57% Dactylis glomerata, 10% Phleum pratense, 8% Poa pratensis, 7% Festuca rubra, .... may be attributed to microbial protein synthesis being energetically more efficient on ..... Association of Official Analytical Chemists, Inc.

Electronic technology

International Nuclear Information System (INIS)

Kim, Jin Su

2010-07-01

This book is composed of five chapters, which introduces electronic technology about understanding of electronic, electronic component, radio, electronic application, communication technology, semiconductor on its basic, free electron and hole, intrinsic semiconductor and semiconductor element, Diode such as PN junction diode, characteristic of junction diode, rectifier circuit and smoothing circuit, transistor on structure of transistor, characteristic of transistor and common emitter circuit, electronic application about electronic equipment, communication technology and education, robot technology and high electronic technology.

The Electron

Energy Technology Data Exchange (ETDEWEB)

Thomson, George

1972-01-01

Electrons are elementary particles of atoms that revolve around and outside the nucleus and have a negative charge. This booklet discusses how electrons relate to electricity, some applications of electrons, electrons as waves, electrons in atoms and solids, the electron microscope, among other things.

Determination of the electron-electron collisional frequency by means of plasma electron spectroscopy

International Nuclear Information System (INIS)

Kolokolov, N.B.; Kudryavtsev, A.A.; Romanenko, V.A.

1989-01-01

Methods of controlling fast part of electron distribution function (DF) in nonlocal regime of current-free plasma are suggested and realized. Artificially created step in DF fast part has a simple link with frequencies of electron-electron and elastic electron-atom collisions that may be defined in the corresponding experiments

Electron beam-plasma interaction and electron-acoustic solitary waves in a plasma with suprathermal electrons

Science.gov (United States)

Danehkar, A.

2018-06-01

Suprathermal electrons and inertial drifting electrons, so called electron beam, are crucial to the nonlinear dynamics of electrostatic solitary waves observed in several astrophysical plasmas. In this paper, the propagation of electron-acoustic solitary waves (EAWs) is investigated in a collisionless, unmagnetized plasma consisting of cool inertial background electrons, hot suprathermal electrons (modeled by a κ-type distribution), and stationary ions. The plasma is penetrated by a cool electron beam component. A linear dispersion relation is derived to describe small-amplitude wave structures that shows a weak dependence of the phase speed on the electron beam velocity and density. A (Sagdeev-type) pseudopotential approach is employed to obtain the existence domain of large-amplitude solitary waves, and investigate how their nonlinear structures depend on the kinematic and physical properties of the electron beam and the suprathermality (described by κ) of the hot electrons. The results indicate that the electron beam can largely alter the EAWs, but can only produce negative polarity solitary waves in this model. While the electron beam co-propagates with the solitary waves, the soliton existence domain (Mach number range) becomes narrower (nearly down to nil) with increasing the beam speed and the beam-to-hot electron temperature ratio, and decreasing the beam-to-cool electron density ratio in high suprathermality (low κ). It is found that the electric potential amplitude largely declines with increasing the beam speed and the beam-to-cool electron density ratio for co-propagating solitary waves, but is slightly decreased by raising the beam-to-hot electron temperature ratio.

The Variable Effect of Polyploidization on the Phenotype in Escallonia.

Science.gov (United States)

Denaeghel, Hanne E R; Van Laere, Katrijn; Leus, Leen; Lootens, Peter; Van Huylenbroeck, Johan; Van Labeke, Marie-Christine

2018-01-01

To induce new variation within the Escallonia genus, chromosome doubling was performed in E. rubra, E. rosea , and E. illinita , three important species within this genus of mainly evergreen woody ornamental species. Obtained tetraploids and diploid controls were analyzed for rooting capacity, leaf and flower characteristics, and plant architecture using image analysis and cold tolerance. In the present study, a breeders' collection of 23 accessions was characterized cytogenetically and described morphologically. All analyzed species and cultivars were diploid (2n = 2x = 24), with exception of E. pendula , a tetraploid. Today, breeding in Escallonia is limited to lucky finds in seedling populations and few efforts in interspecific hybridization. Three selected Escallonia species underwent an in vitro chromosome doubling with both oryzalin and trifluralin applied as either a continuous or shock treatment. The treatments successfully induced polyploids in all three species. Image analysis revealed that tetraploid E. rosea had decreased shoot length (from 3.8 to 1.3 cm), higher circularity and more dense growth habit compared to diploids. No significant changes in cold tolerance were seen. Tetraploid E. illinita did not differ in shoot length, but an increased outgrowth of axillary buds on the main axis led to denser plants. For tetraploid E. rubra , an increase in plant height (from 4.9 to 5.5 cm) was observed together with a large decrease in circularity and density due to a more polar outgrowth of branches on the main axis. E. rubra tetraploids bore larger flowers than diploids and had an increased cold tolerance (from -7.7 to -11.8°C). Leaf width and area of tetraploids increased for both E. illinita and E. rubra , while a decrease was seen in E. rosea genotypes. For all three species, the rooting capacity of the tetraploids did not differ from the diploids. We conclude that the effect of polyploidization on Escallonia was highly variable and species dependent.

Comparison of the digestibility of abalone (Haliotis discus hannai) produced by four different processing treatments%四种加工方式对皱纹盘鲍制品消化特性的影响

Institute of Scientific and Technical Information of China (English)

万楚君; 游银川; 翁凌; 张凌晶; 刘光明; 曹敏杰

2017-01-01

为了探讨不同加工方式对皱纹盘鲍制品消化特性的影响,分析了生鲜、煮制、罐制和干制4种方式对鲍鱼肌肉蛋白在消化酶作用下的分解情况.利用模拟胃肠液消化及SDS-PAGE比较分析不同加工方式对鲍鱼肌肉消化特性的影响,并通过扫描电镜观察4种加工方式下鲍鱼肌肉组织微观结构的差异.结果显示,与生鲜鲍鱼相比,经煮制的鲍鱼较易被消化,罐制加工产品最易被消化,而干制鲍鱼最难被消化.不同加工方式对鲍鱼肌肉的组织结构有较大影响.进一步对不同皱纹盘鲍制品模拟胃肠液消化终产物的生物活性进行研究,发现它们对血管紧张素转换酶(ACE)的抑制活性(IC50)依次为罐制(464.2μg/mL)<干制(665.4μg/mL)<煮制(775.7μg/mL)<生鲜(803.9μg/mL).研究表明,不同加工方式对鲍鱼制品在机体内的消化特性及产物对ACE抑制活性存在差异,为优化鲍鱼制品生产加工提供了一定的参考.%In order to know the effect of different processing methods on protein digestion of abalone (Haliotis discus hannai), the effects of four processing methods including raw, boiling, canning, and drying on the digestibility of abalone muscular proteins were investigated. Simulated gastric fluid (SGF) as well as simulated intestinal fluid (SIF) was used to study the effects ofin vitro digestion. The products were evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Scanning electronic microscopy (SEM) was used to observe the differences in the fiber of the four products. The results showed that the digestibility of proteins in canned abalone was the highest among the four processing methods. Proteins from dried abalone were most resistant to digestion both in SGF and SIF. The four processing methods revealed different fiber structures under SEM. Furthermore, the angiotensin-I converting enzyme (ACE) inhibitory activity of the digested products exhibited the

Laser Imaging Polarimetry of Nacre.

Science.gov (United States)

Jones, Joshua A; Metzler, Rebecca A; D'Addario, Anthony J; Burgess, Carrie; Regan, Brian; Spano, Samantha; Cvarch, Ben A; Galvez, Enrique J

2018-03-25

Nacre is a complex biomaterial made of aragonite-tablet bricks and organic mortar that is considerably resilient against breakage. Nacre has been studied with a wide range of laboratory techniques, leading to understanding key fundamentals, and informing the creation of bio-inspired materials. In this article we present an optical polarimetric technique to investigate nacre, taking advantage of the translucence and birefringence of its micro-components. We focus our study on three classes of mollusks that have nacreous shells: bivalve (Pinctada fucata), gastropod (Haliotis asisina and Haliotis rufescens) and cephalopod (Nautilus pompilius). We sent polarized light from a laser through thin samples of nacre and did imaging polarimetry of the transmitted light. We observed clear distinctions between the structures of bivalve and gastropod, due to the spatial variation of their birefringence. The patterns for cephalopod were more similar to bivalve than gastropod. Bleaching of the samples disrupted the transmitted light. Subsequent refilling of the bivalve and gastropod nacre samples with oil produced optical patterns similar to those of unbleached samples. In cephalopod samples we found that bleaching produced irreversible changes in the optical pattern. This article is protected by copyright. All rights reserved.

杨梅叶水溶性提取物的抗氧化、抗菌活性与防腐应用

Czech Academy of Sciences Publication Activity Database

君酸, 杨.; 云酸, 朱.; 清酸, 吴.; 洁酸, 尹.; Langhansová, Lenka; Vaněk, Tomáš; 生酸, 高.

2014-01-01

Roč. 28, č. 2 (2014), s. 198-202 ISSN 1006-2513 Institutional support: RVO:61389030 Keywords : Myrica rubra leaf * antioxidation * antisepsis Subject RIV: EF - Botanics http://d.g.wanfangdata.com.cn/Periodical_zgsptjj201402029.aspx

Electronic Government and Electronic Participation

NARCIS (Netherlands)

Tambouris, E; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K; Gascó, M; Klievink, A.J.; Lindgren, I; Milano, M; Panagiotopoulos, P; Pardo, T.A.; Parycek, P; Sæbø, Ø

2016-01-01

Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies.This book presents papers from the 14th International Federation for Information

Electronic Government and Electronic Participation

NARCIS (Netherlands)

Tambouris, E.; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K.; Gascó, M.; Klievink, A.J.; Lindgren, I.; Milano, M.; Panagiotopoulos, P.; Pardo, T.A.; Parycek, P.; Sæbø, O.

2015-01-01

Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies. This book presents papers from the 14th International Federation for Information

Electron detector

International Nuclear Information System (INIS)

Hashimoto, H.; Mogami, A.

1975-01-01

A device for measuring electron densities at a given energy level in an electron beam or the like having strong background noise, for example, in the detection of Auger electric energy spectrums is described. An electron analyzer passes electrons at the given energy level and at the same time electrons of at least one adjacent energy level. Detecting means associated therewith produce signals indicative of the densities of the electrons at each energy level and combine these signals to produce a signal indicative of the density of the electrons of the given energy level absent background noise

Electron-electron interactions in artificial graphene

Science.gov (United States)

Rasanen, Esa

2013-03-01

Recent advances in the creation and modulation of graphenelike systems are introducing a science of ``designer Dirac materials.'' In its original definition, artificial graphene is a man-made nanostructure that consists of identical potential wells (quantum dots) arranged in an adjustable honeycomb lattice in the two-dimensional electron gas. As our ability to control the quality of artificial graphene samples improves, so grows the need for an accurate theory of its electronic properties, including the effects of electron-electron interactions. Here we determine those effects on the band structure and on the emergence of Dirac points, and discuss future investigations and challenges in this field.

Decal electronics for printed high performance cmos electronic systems

KAUST Repository

Hussain, Muhammad Mustafa

2017-11-23

High performance complementary metal oxide semiconductor (CMOS) electronics are critical for any full-fledged electronic system. However, state-of-the-art CMOS electronics are rigid and bulky making them unusable for flexible electronic applications. While there exist bulk material reduction methods to flex them, such thinned CMOS electronics are fragile and vulnerable to handling for high throughput manufacturing. Here, we show a fusion of a CMOS technology compatible fabrication process for flexible CMOS electronics, with inkjet and conductive cellulose based interconnects, followed by additive manufacturing (i.e. 3D printing based packaging) and finally roll-to-roll printing of packaged decal electronics (thin film transistors based circuit components and sensors) focusing on printed high performance flexible electronic systems. This work provides the most pragmatic route for packaged flexible electronic systems for wide ranging applications.

Electron-beam-induced-current and active secondary-electron voltage-contrast with aberration-corrected electron probes

Energy Technology Data Exchange (ETDEWEB)

Han, Myung-Geun, E-mail: mghan@bnl.gov [Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Garlow, Joseph A. [Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Materials Science and Engineering Department, Stony Brook University, Stony Brook, NY 11794 (United States); Marshall, Matthew S.J.; Tiano, Amanda L. [Department of Chemistry, Stony Brook University, Stony Brook, NY 11974 (United States); Wong, Stanislaus S. [Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Department of Chemistry, Stony Brook University, Stony Brook, NY 11974 (United States); Cheong, Sang-Wook [Department of Physics and Astronomy, Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ 08854 (United States); Walker, Frederick J.; Ahn, Charles H. [Department of Applied Physics and Center for Research on Interface Structures and Phenomena, Yale University, New Haven, CT 06520 (United States); Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06520 (United States); Zhu, Yimei [Condensed Matter Physics & Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2017-05-15

Highlights: • Electron-beam-induced-current (EBIC) and active secondary-electron voltage-contrast (SE-VC) are demonstrated in STEM mode combined with in situ electrical biasing in a TEM. • Electrostatic potential maps in ferroelectric thin films, multiferroic nanowires, and single crystals obtained by off-axis electron holography were compared with EBIC and SE-VC data. • Simultaneous EBIC and active SE-VC performed with atomic resolution STEM are demonstrated. - Abstract: The ability to map out electrostatic potentials in materials is critical for the development and the design of nanoscale electronic and spintronic devices in modern industry. Electron holography has been an important tool for revealing electric and magnetic field distributions in microelectronics and magnetic-based memory devices, however, its utility is hindered by several practical constraints, such as charging artifacts and limitations in sensitivity and in field of view. In this article, we report electron-beam-induced-current (EBIC) and secondary-electron voltage-contrast (SE-VC) with an aberration-corrected electron probe in a transmission electron microscope (TEM), as complementary techniques to electron holography, to measure electric fields and surface potentials, respectively. These two techniques were applied to ferroelectric thin films, multiferroic nanowires, and single crystals. Electrostatic potential maps obtained by off-axis electron holography were compared with EBIC and SE-VC to show that these techniques can be used as a complementary approach to validate quantitative results obtained from electron holography analysis.

Electronic Commerce and Electronic Business

Indian Academy of Sciences (India)

R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

This special issue is motivated by the recent upsurge of research activity in the areas of electronic commerce and electronic business both in India and all over the world. The current ... Monte Carlo methods for pricing financial options are then.

Electron optical characteristics of a concave electrostatic electron mirror for a scanning electron microscope

International Nuclear Information System (INIS)

Hamarat, R.T.; Witzani, J.; Hoerl, E.M.

1984-08-01

Numerical computer calculations are used to explore the design characteristics of a concave electrostatic electron mirror for a mirror attachment for a conventional scanning electron microscope or an instrument designed totally as a scanning electron mirror microscope. The electron paths of a number of set-ups are calculated and drawn graphically in order to find the optimum shape and dimensions of the mirror geometry. This optimum configuration turns out to be the transition configuration between two cases of electron path deflection, towards the optical axis of the system and away from it. (Author)

Electronic processes in organic electronics bridging nanostructure, electronic states and device properties

CERN Document Server

Kudo, Kazuhiro; Nakayama, Takashi; Ueno, Nobuo

2015-01-01

The book covers a variety of studies of organic semiconductors, from fundamental electronic states to device applications, including theoretical studies. Furthermore, innovative experimental techniques, e.g., ultrahigh sensitivity photoelectron spectroscopy, photoelectron yield spectroscopy, spin-resolved scanning tunneling microscopy (STM), and a material processing method with optical-vortex and polarization-vortex lasers, are introduced. As this book is intended to serve as a textbook for a graduate level course or as reference material for researchers in organic electronics and nanoscience from electronic states, fundamental science that is necessary to understand the research is described. It does not duplicate the books already written on organic electronics, but focuses mainly on electronic properties that arise from the nature of organic semiconductors (molecular solids). The new experimental methods introduced in this book are applicable to various materials (e.g., metals, inorganic and organic mater...

Decal electronics for printed high performance cmos electronic systems

KAUST Repository

Hussain, Muhammad Mustafa; Sevilla, Galo Torres; Cordero, Marlon Diaz; Kutbee, Arwa T.

2017-01-01

High performance complementary metal oxide semiconductor (CMOS) electronics are critical for any full-fledged electronic system. However, state-of-the-art CMOS electronics are rigid and bulky making them unusable for flexible electronic applications

Precession mechanism of spin relaxation at frequent electron-electron collisions

CERN Document Server

Glazov, M M

2002-01-01

It is shown that the spin relaxation mechanism in the two-dimensional electron gas, is controlled not only through the electron pulse relaxation processes, determining the mobility, but through the electron-electron collisions as well. It is decided to use the kinetic equation, describing the electron spin mixing in the k-space, for determining the spin relaxation time tau sub s at frequent electron-electron collisions. The tau sub s time is calculated for the nondegenerated electron gas both with an account and with no account of the exchange interaction

Practical electronics handbook

CERN Document Server

Sinclair, Ian R

2013-01-01

Practical Electronics Handbook, Third Edition provides the frequently used and highly applicable principles of electronics and electronic circuits.The book contains relevant information in electronics. The topics discussed in the text include passive and active discrete components; linear and digital I.C.s; microprocessors and microprocessor systems; digital-analogue conversions; computer aids in electronics design; and electronic hardware components.Electronic circuit constructors, service engineers, electronic design engineers, and anyone with an interest in electronics will find the book ve

Composition quantification of electron-transparent samples by backscattered electron imaging in scanning electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Müller, E., E-mail: erich.mueller@kit.edu; Gerthsen, D.

2017-02-15

The contrast of backscattered electron (BSE) images in scanning electron microscopy (SEM) depends on material parameters which can be exploited for composition quantification if some information on the material system is available. As an example, the In-concentration in thin In{sub x}Ga{sub 1−x}As layers embedded in a GaAs matrix is analyzed in this work. The spatial resolution of the technique is improved by using thin electron-transparent specimens instead of bulk samples. Although the BSEs are detected in a comparably small angular range by an annular semiconductor detector, the image intensity can be evaluated to determine the composition and local thickness of the specimen. The measured intensities are calibrated within one single image to eliminate the influence of the detection and amplification system. Quantification is performed by comparison of experimental and calculated data. Instead of using time-consuming Monte-Carlo simulations, an analytical model is applied for BSE-intensity calculations which considers single electron scattering and electron diffusion. - Highlights: • Sample thickness and composition are quantified by backscattered electron imaging. • A thin sample is used to achieve spatial resolution of few nanometers. • Calculations are carried out with a time-saving electron diffusion model. • Small differences in atomic number and density detected at low electron energies.

Nonlinear electron-acoustic rogue waves in electron-beam plasma system with non-thermal hot electrons

Science.gov (United States)

Elwakil, S. A.; El-hanbaly, A. M.; Elgarayh, A.; El-Shewy, E. K.; Kassem, A. I.

2014-11-01

The properties of nonlinear electron-acoustic rogue waves have been investigated in an unmagnetized collisionless four-component plasma system consisting of a cold electron fluid, non-thermal hot electrons obeying a non-thermal distribution, an electron beam and stationary ions. It is found that the basic set of fluid equations is reduced to a nonlinear Schrodinger equation. The dependence of rogue wave profiles on the electron beam and energetic population parameter are discussed. The results of the present investigation may be applicable in auroral zone plasma.

Electron-cyclotron-resonant-heated electron distribution functions

International Nuclear Information System (INIS)

Matsuda, Y.; Nevins, W.M.; Cohen, R.H.

1981-01-01

Recent studies at Lawrence Livermore National Laboratory (LLNL) with a bounce-averaged Fokker-Planck code indicate that the energetic electron tail formed by electron-cyclotron resonant heating (ECRH) at the second harmonic is not Maxwellian. We present the results of our bounce-averaged Fokker-Planck code along with some simple analytic models of hot-electron distribution functions

Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

International Nuclear Information System (INIS)

Seletskiy, Sergey M.; Rochester U.

2005-01-01

Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the first cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cooling. The Recycler Electron Cooler (REC) is the key component of the Tevatron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV carrying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 (micro)rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible. Chapter 1 is an introduction where I describe briefly the theory and the history of electron cooling, and derive the requirements to the quality of electron beam and requirements to the basic parameters of the Recycler Electron Cooler. Chapter 2 is devoted to the theoretical consideration of the motion of electrons in the cooling section, description of the cooling section and of the measurement of the magnetic fields. In Chapter 3 I consider different factors that increase the effective electron angle in the cooling section and suggest certain algorithms for the suppression of parasitic angles. Chapter 4 is devoted to the measurements of the energy of the electron beam. In the concluding Chapter 5 I review

Double differential distributions of electron emission in ion-atom and electron-atom collisions using an electron spectrometer

International Nuclear Information System (INIS)

Misra, Deepankar; Thulasiram, K.V.; Fernandes, W.; Kelkar, Aditya H.; Kadhane, U.; Kumar, Ajay; Singh, Yeshpal; Gulyas, L.; Tribedi, Lokesh C.

2009-01-01

We study electron emission from atoms and molecules in collisions with fast electrons and heavy ions (C 6+ ). The soft collision electrons (SE), two center electron emission (TCEE), the binary encounter (BE) events and the KLL Auger lines along with the elastically scattered peaks (in electron collisions) are studied using a hemispherical electrostatic electron analyzer. The details of the measurements along with description of the spectrometer and data acquisition system are given. The angular distributions of the low energy (few eV) electrons in soft collisions and the binary encounter electrons at keV energies are compared with quantum mechanical models based on the first Born (B1) and the continuum distorted wave-Eikonal initial state approximation (CDW-EIS).

VIRTUAL ELECTRONIC COMPONENTS OF THE ELECTRONIC EQUIPMENT

Directory of Open Access Journals (Sweden)

E. Lazarevich

2013-01-01

Full Text Available The article is present new idea of the creation, developments and improvements of the electronic equipment of complex systems by means of the virtual electronic components. The idea of the virtual electronic components is a presentation and perception of the creation and developments of the equipment on two forming: real – in the manner of standard marketed block of the intellectual property and image – in the manner of virtual component. The real component in most cases slows the development of the electronic equipment. The imaginary component is the «locomotive» of development of the electronic equipment. The Imaginary component contains the scientific has brushed against developer. The scientific has brushed against developer reveals of itself in the manner of virtual component on the modern level of the design rates of microelectronics.

A new stage of nuclear electronics-particle electronics

International Nuclear Information System (INIS)

Xi Deming

1987-01-01

The rapid development of high energy physics experiments has pushed the nuclear electronics to a new stage, i.e. the particle electronics. In this paper the background, main features and recent trends of the particle electronics are expounded

Electron transport effects in ion induced electron emission

Energy Technology Data Exchange (ETDEWEB)

Dubus, A. [Universite Libre de Bruxelles, Service de Metrologie Nucleaire (CP 165/84), 50 av. FD Roosevelt, B-1050 Brussels (Belgium)]. E-mail: adubus@ulb.ac.be; Pauly, N. [Universite Libre de Bruxelles, Service de Metrologie Nucleaire (CP 165/84), 50 av. FD Roosevelt, B-1050 Brussels (Belgium); Roesler, M. [Karl-Pokern-Str. 12, D-12587 Berlin (Germany)

2007-03-15

Ion induced electron emission (IIEE) is usually described as a three-step process, i.e. electron excitation by the incident projectile, electron transport (and multiplication) and electron escape through the potential barrier at the surface. In many cases, the first step of the process has been carefully described. The second step of the process, i.e. electron transport and multiplication, has often been treated in a very rough way, a simple decreasing exponential law being sometimes used. It is precisely the aim of the present work to show the importance of a correct description of electron transport and multiplication in a theoretical calculation of IIEE. A short overview of the electron transport models developed for IIEE is given in this work. The so-called 'Infinite medium slowing-down model' often used in recent works is evaluated by means of Monte Carlo simulations. In particular, the importance of considering correctly the semi-infinite character of the medium and the boundary condition at the vacuum-medium interface is discussed. Quantities like the electron escape depth are also briefly discussed. This evaluation has been performed in the particular case of protons (25keV

Studying electron-PAG interactions using electron-induced fluorescence

Science.gov (United States)

Narasimhan, Amrit; Grzeskowiak, Steven; Ostrander, Jonathan; Schad, Jonathon; Rebeyev, Eliran; Neisser, Mark; Ocola, Leonidas E.; Denbeaux, Gregory; Brainard, Robert L.

2016-03-01

In extreme ultraviolet (EUV) lithography, 92 eV photons are used to expose photoresists. Typical EUV resists are organic-based and chemically amplified using photoacid generators (PAGs). Upon exposure, PAGs produce acids which catalyze reactions that result in changes in solubility. In EUV lithography, photo- and secondary electrons (energies of 10- 80 eV) play a large role in PAG acid-production. Several mechanisms for electron-PAG interactions (e.g. electron trapping, and hole-initiated chemistry) have been proposed. The aim of this study is to explore another mechanism - internal excitation - in which a bound PAG electron can be excited by receiving energy from another energetic electron, causing a reaction that produces acid. This paper explores the mechanism of internal excitation through the analogous process of electron-induced fluorescence, in which an electron loses energy by transferring that energy to a molecule and that molecule emits a photon rather than decomposing. We will show and quantify electron-induced fluorescence of several fluorophores in polymer films to mimic resist materials, and use this information to refine our proposed mechanism. Relationships between the molecular structure of fluorophores and fluorescent quantum yield may aid in the development of novel PAGs for EUV lithography.

Electron-electron Thomas peak in fast transfer ionization

International Nuclear Information System (INIS)

Tolmanov, S. G.; McGuire, J. H.

2000-01-01

''Thomas process'' is a name used for a family of singular two-step processes that can lead to electron transfer. The Thomas process of the ''second kind,'' occurring in reactions with both transfer and ionization, utilizes the e-e scattering in the second step, so this Thomas process requires the dynamics of the electron-electron interaction. We calculate numerically the second order element of an S matrix and corresponding cross sections for the transfer ionization process. We find that the position and shape of the Thomas peak depend on both electron-electron and the electron-nucleus interaction. Also the direct and exchange amplitudes are equal at the peak position. We test the peaking approximation used for transfer ionization. Our results can be compared to experimental results for p + +He→H+He 2+ +e - . (c) 2000 The American Physical Society

Electron Tree

DEFF Research Database (Denmark)

Appelt, Ane L; Rønde, Heidi S

2013-01-01

The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

Electronic Raman response in electron-doped cuprate superconductors

International Nuclear Information System (INIS)

Geng Zhihao; Feng Shiping

2012-01-01

The electronic Raman response in the electron-doped cuprate superconductors is studied based on the t-t'-J model. It is shown that although the domelike shape of the doping dependent peak energy in the B 2g symmetry is a common feature for both electron-doped and hole-doped cuprate superconductors, there are pronounced deviations from a cubic response in the B 2g channel and a linear response in the B 2g channel for the electron-doped case in the low energy limit. It is also shown that these pronounced deviations are mainly caused by a nonmonotonic d-wave gap in the electron-doped cuprate superconductors.

Spectroscopy of electron irradiated polymers in electron microscope

International Nuclear Information System (INIS)

Faraj, S.H.; Salih, S.M.

1981-01-01

The damage induced by energetic electrons in the course of irradiation of polymers in a transmission electron microscope was investigated spectroscopically. Damage on the molecular level has been detected at very low exposure doses. These effects have been induced by electron doses less than that received by the specimen when it is situated at its usual place of the specimen stage in the electron microscope by a factor of 1,000. (author)

Interactions among soil biology, nutrition, and performance of actinorhizal plant species in the H.J. Andrews Experimental Forest of Oregon.

Science.gov (United States)

N.S. Rojas; D.A. Perry; C.Y. Li; L.M. Ganio

2002-01-01

The study examined the effect of Frankia, macronutrients, micronutrients, mycorrhizal fungi, and plant-growth-promoting fluorescent Pseudomonas sp. on total biomass, nodule weight, and nitrogen fixation of red aider (Alnus rubra) and snowbrush (Ceanothus velutinus) under greenhouse conditions. The soil...

Electron spectroscopy in the fundamental process of electron-nucleus bremsstrahlung

International Nuclear Information System (INIS)

Hillenbrand, Pierre-Michel

2013-07-01

Within the scope of this thesis the fundamental process of electron-nucleus bremsstrahlung was studied in inverse kinematics at the Experimental Storage Ring ESR at GSI. For the system U 88+ + N 2 at 90 MeV/u it was shown, that by using inverse kinematics coincidence measurements between the scattered electron and the emitted photon can be performed for the case, in which the incoming electron transfers almost all of its kinetic energy onto the emitted photon. The sensitivity to the fundamental process could be achieved by measuring triple differential cross sections as a function of the emission angle of the photon and the scattered electron as well as the energy of the scattered electron. The optics of the magnetic electron spectrometer used were thoroughly revised and optimized to the experimental requirements. Analyzing different coincidences in this collision system, it was possible to determine the contributions to the electron distribution arising from radiative electron capture to the projectile continuum, nonradiative electron capture to the projectile continuum, and electron loss to the projectile continuum. The experimental results of each of these processes were compared to theoretical calculations. The electron spectra for the radiative and the nonradiative electron capture to continuum clearly reproduce the opposite asymmetry predicted by theory. Furthermore electron spectra for collisions of U 28+ with different gases were measured.

`Twisted' electrons

Science.gov (United States)

Larocque, Hugo; Kaminer, Ido; Grillo, Vincenzo; Leuchs, Gerd; Padgett, Miles J.; Boyd, Robert W.; Segev, Mordechai; Karimi, Ebrahim

2018-04-01

Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron's charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons.

The electron

International Nuclear Information System (INIS)

Hestenes, David; Weingartshofer, Antonio

1991-01-01

The stupendous successes of the Dirac equation and quantum electro-dynamics have established the electron as the best understood of the fundamental constituents of matter. Nevertheless, physicists agree that the electron still has secrets to reveal. Moreover, powerful new theoretical and experimental tools for probing those secrets have been sharpened during the last decade. This workshop was organized to bring theorists and experimentalists together to discuss their common goal of knowing the electron. Present state and future prospects for progress toward that goal are here described. The theoretical papers encompass a wide range of views on the electron. Several argue that the 'Zitter-bewegung' is more than a mathematical peculiarity of the Dirac equation, that it may well be a real physical phenomenon and worthy of serious study, theoretically and experimentally. Besides generating the electron spin and magnetic moment, the 'Zitterbewegung' may be a vital clue to electron structure and self-interaction. Some of the papers employ a radical new formulation of the Dirac theory which reveals a hidden geo-metric structure in the theory that supports a 'Zitterbewegung' inter-pretation. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. First, techniques for confining single electrons for long term study have led to the most accurate measurements of the electron magnetic moment. Second, the interaction of high intensity laser fields with atoms and electrons have revealed striking new phenomena such as multiphoton ionization. refs.; figs.; tabs

Basic electronics

CERN Document Server

Holbrook, Harold D

1971-01-01

Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

Electron-electron scattering and mobilities in semiconductors and quantum wells

International Nuclear Information System (INIS)

Lyo, S.K.

1986-01-01

The effect of electron-electron scattering on the mobility in semiconductors and semiconductor quantum wells is examined. A general exact formula is derived for the mobility, when the electron-electron collision rate is much faster than other scattering rates such as those by ionized impurities and phonons. In this limit, the transport relaxation rate is independent of the carrier's energy and contributions to the inverse mobility from individual scattering mechanism add up. The mobility becomes significantly reduced from its value in the absence of electron-electron scattering. When the collision rates are not necessarily dominated by electron-electron scattering, the mobility is calculated by the Kohler-Sondheimer variational method in the presence of ionized-impurity scattering and acoustic-phonon scattering in a nondegenerate two-dimensional quantum well

Modified Monte Carlo method for study of electron transport in degenerate electron gas in the presence of electron-electron interactions, application to graphene

Science.gov (United States)

Borowik, Piotr; Thobel, Jean-Luc; Adamowicz, Leszek

2017-07-01

Standard computational methods used to take account of the Pauli Exclusion Principle into Monte Carlo (MC) simulations of electron transport in semiconductors may give unphysical results in low field regime, where obtained electron distribution function takes values exceeding unity. Modified algorithms were already proposed and allow to correctly account for electron scattering on phonons or impurities. Present paper extends this approach and proposes improved simulation scheme allowing including Pauli exclusion principle for electron-electron (e-e) scattering into MC simulations. Simulations with significantly reduced computational cost recreate correct values of the electron distribution function. Proposed algorithm is applied to study transport properties of degenerate electrons in graphene with e-e interactions. This required adapting the treatment of e-e scattering in the case of linear band dispersion relation. Hence, this part of the simulation algorithm is described in details.

Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

Energy Technology Data Exchange (ETDEWEB)

Seletskiy, Sergei M. [Univ. of Rochester, NY (United States)

2005-01-01

Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the ¯rst cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cool- ing. The Recycler Electron Cooler (REC) is the key component of the Teva- tron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV car- rying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 ¹rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible.

Microfluidic electronics.

Science.gov (United States)

Cheng, Shi; Wu, Zhigang

2012-08-21

Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

Electron-electron collision effects on the bremsstrahlung emission in Lorentzian plasmas

International Nuclear Information System (INIS)

Jung, Young-Dae; Kato, Daiji

2009-01-01

Electron-electron collision effects on the electron-ion bremsstrahlung process are investigated in Lorentzian plasmas. The effective electron-ion interaction potential is obtained by including the far-field terms caused by electron-electron collisions with an effective Debye length in Lorentzian plasmas. The bremsstrahlung radiation cross section is obtained as a function of the electron energy, photon energy, collision frequency, spectral index and Debye length using the Born approximation for the initial and final states of the projectile electron. It is shown that the non-Maxwellian character suppresses the bremsstrahlung radiation cross section. It is also shown that the electron-electron collision effect enhances the bremsstrahlung emission spectrum. In addition, the bremsstrahlung radiation cross section decreases with an increase in the plasma temperature.

Electron-photon and electron-electron interactions in the presence of strong electromagnetic fields

International Nuclear Information System (INIS)

Surzhykov, A.; Fritzsche, S.; Stoehlker, Th.

2010-01-01

During the last decade, photon emission from highly-charged, heavy ions has been in the focus of intense studies at the GSI accelerator and storage ring facility in Darmstadt. These studies have revealed unique information about the electron-electron and electron-photon interactions in the presence of extremely strong nuclear fields. Apart from the radiative electron capture processes, characteristic photon emission following collisional excitation of projectile ions has also attracted much interest. In this contribution, we summarize the recent theoretical studies on the production of excited ionic states and their subsequent radiative decay. We will pay special attention to the angular and polarization properties of Kα emission from helium-like ions produced by means of dielectronic recombination. The results obtained for this (resonant) capture process will be compared with the theoretical predictions for the characteristic X-rays following Coulomb excitation and radiative recombination of few-electron, heavy ions. Work is supported by Helmholtz Association and GSl under the project VH-NG--421. (author)

Sticker electronics

KAUST Repository

Hussain, Muhammad Mustafa

2017-09-08

Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces. The stickers can be wrappable, placed on surfaces, glued on walls or mirrors or wood or stone, and have electronics (112, 122, 132) which may or may not be ultrathin. Packaging for the electronic sticker can use polymer on cellulose manufacturing and/or three dimensional (3-D) printing. The electronic stickers may provide lighting capability, sensing capability, and/or recharging capabilities.

Electronic Commerce

Directory of Open Access Journals (Sweden)

Slavko Đerić

2016-12-01

Full Text Available Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks, including the Internet. Electronic commerce is not limited just to buying and selling, but it also includes all pre-sales and after-sales ongoing activities along the supply chain. Introducing electronic commerce, using the Internet and Web services in business, realizes the way to a completely new type of economy - internet economy.

Observation of the two-electron cusp in atomic collisions. Evidence for strong electron-electron correlation

International Nuclear Information System (INIS)

Sarkadi, L.; Orban, A.

2007-01-01

Complete text of publication follows. In this report we present experimental data for a process when two electrons with velocity vectors equal to that of the projectile are emitted from collisions. By observing the two electron cusp the study of the threshold phenomenon for two-electron break-up is possible. It is a particularly interesting question whether the outgoing charged projectile can attract the two repulsing electrons so strongly that the two-electron cusp is formed. If it is so, a further question arises: Are the two electrons correlated in the final state as it is predicted by the Wannier theory? The experiments have been done at the 1 MeV VdG accelerator of ATOMKI using our TOF spectrometer. The first measurements clearly showed the formation of the two-electron cusp and signature of the electron correlation in 200 keV He 0 +He collisions. These promising results motivated us to carry out the experiment at 100 keV beam energy where the coincidence count rate is still reasonable but the energy resolution is better. For an acceptable data acquisition time we improved our data acquisition and data processing system for triple coincidence measurements. In Fig. 1a we present our measured relative fourfold differential cross section (FDCS) that shows strong electron correlation. For a comparison, in Fig. 1b we displayed the contour plot for uncorrelated electron pair emission. These latter data were synthesized artificially, generating the energies of the electron pairs from two independent double coincidence experiments. In both figures the distributions are characterized by two ridges. In Fig. 1b the ridges are perpendicular straight lines (E 1 = E 2 .13.6 eV). As a result of the correlation, the ridges in Fig. 1a are distorted in such a way that they have a joint straight-line section following the line E 1 + E 2 = 27.2 eV. This means that the electron pairs in the vicinity of the cusp maximum are emitted with a center of- mass velocity equal to that of

Electronics and Information

Institute of Scientific and Technical Information of China (English)

无

2008-01-01

@@ Previously founded as CCPITMachinery and Electronics Sub-council and CCOIC Machinery and Electronics Chamber of Corn-merce in June, 1988, CCPIT Electronics Sub-Council and CCOIC Electronics Chamber of Commerce were established in May, 1993, and then renamed as CCPIT Electronics and Information Industry Sub-council and CCOIC Electronics and Infor-mation Industry Chamber of Commerce (CCPITECC) in September 1999.

Spontaneous and stimulated emission induced by an electron, electron bunch, and electron beam in a plasma

International Nuclear Information System (INIS)

Kuzelev, M V; Rukhadze, A A

2008-01-01

Two fundamental mechanisms - the Cherenkov effect and anomalous Doppler effect - underlying the emission by an electron during its superluminal motion in medium are considered. Cherenkov emission induced by a single electron and a small electron bunch is spontaneous. In the course of spontaneous Cherenkov emission, the translational motion of an electron is slowed down and the radiation energy grows linearly with time. As the number of radiating electrons increases, Cherenkov emission becomes stimulated. Stimulated Cherenkov emission represents a resonance beam instability. This emission process is accompanied by longitudinal electron bunching in the beam or by the breaking of an electron bunch into smaller bunches, in which case the radiation energy grows exponentially with time. In terms of the longitudinal size L e of the electron bunch there is a transition region λ e 0 -1 between the spontaneous and stimulated Cherenkov effects, where λ is the average radiation wavelength, and δ 0 is the dimensionless (in units of the radiation frequency) growth rate of the Cherenkov beam instability. The range to the left of this region is dominated by spontaneous emission, whereas the range to the right of this region is dominated by stimulated emission. In contrast to the Vavilov-Cherenkov effect, the anomalous Doppler effect should always (even for a single electron) be considered as stimulated, because it can only be explained by accounting for the reverse action of the radiation field on the moving electron. During stimulated emission in conditions where anomalous Doppler effect shows itself, an electron is slowed down and spins up; in this case, the radiation energy grows exponentially with time. (reviews of topical problems)

Looking for the ants: selection of oviposition sites by two myrmecophilous butterfly species

NARCIS (Netherlands)

Wynhoff, I.; Grutters, M.; Langevelde, van F.

2008-01-01

Obligate myrmecophilous butterfly species, such as Maculinea teleius and M. nausithous that hibernate as caterpillar in nests of the ant species Myrmica scabrinodis and M. rubra respectively, have narrowly defined habitat requirements. One would expect that these butterflies are able to select for

Evaluation of Methods for Physical Characterization of the Fine Particle Emissions from Two Residential Wood Combustion Appliances

Science.gov (United States)

The fine particulate matter (PM) emissions from a U. S. certified non-catalytic wood stove and a zero clearance fireplace burning Quercus rubra L. (northern red oak) and Pseudotsuga menziesii (Douglas fir) cordwood each at two different moisture levels were determined. Emission t...

High perveance electron gun for the electron cooling system

International Nuclear Information System (INIS)

Korotaev, Yu.; Meshkov, I.; Petrov, A.; Sidorin, A.; Smirnov, A.; Syresin, E.; Titkova, I.

2000-01-01

The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 μA/V 3/2 , Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual)

High perveance electron gun for the electron cooling system

CERN Document Server

Korotaev, Yu V; Petrov, A; Sidorin, A; Smirnov, A; Syresin, E M; Titkova, I

2000-01-01

The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 mu A/V sup 3 sup / sup 2 , Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual).

Study of single-electron excitations by electron microscopy

International Nuclear Information System (INIS)

Craven, A.J.; Gibson, J.M.; Howie, A.; Spalding, D.R.

1978-01-01

The inelastic scattering of fast electrons by the excitation of L-shell electrons at a stacking fault in silicon has been studied with a scanning transmission electron microscope. It was found that the bright-field stacking fault contrast is preserved in the filtered L-shell-loss signal at 100 eV. This result is discussed in terms of the delocalization of the excitation mechanism. It is concluded that localization effects will typically become significant only for energy transfers greater than 1 keV from a fast electron of energy 80 keV. (author)

Syringe injectable electronics

Science.gov (United States)

Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M.

2015-01-01

Seamless and minimally-invasive three-dimensional (3D) interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating syringe injection and subsequent unfolding of submicrometer-thick, centimeter-scale macroporous mesh electronics through needles with a diameter as small as 100 micrometers. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with > 90% device yield. We demonstrate several applications of syringe injectable electronics as a general approach for interpenetrating flexible electronics with 3D structures, including (i) monitoring of internal mechanical strains in polymer cavities, (ii) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (iii) in vivo multiplexed neural recording. Moreover, syringe injection enables delivery of flexible electronics through a rigid shell, delivery of large volume flexible electronics that can fill internal cavities and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics. PMID:26053995

Electronic Nose and Electronic Tongue

Science.gov (United States)

Bhattacharyya, Nabarun; Bandhopadhyay, Rajib

Human beings have five senses, namely, vision, hearing, touch, smell and taste. The sensors for vision, hearing and touch have been developed for several years. The need for sensors capable of mimicking the senses of smell and taste have been felt only recently in food industry, environmental monitoring and several industrial applications. In the ever-widening horizon of frontier research in the field of electronics and advanced computing, emergence of electronic nose (E-Nose) and electronic tongue (E-Tongue) have been drawing attention of scientists and technologists for more than a decade. By intelligent integration of multitudes of technologies like chemometrics, microelectronics and advanced soft computing, human olfaction has been successfully mimicked by such new techniques called machine olfaction (Pearce et al. 2002). But the very essence of such research and development efforts has centered on development of customized electronic nose and electronic tongue solutions specific to individual applications. In fact, research trends as of date clearly points to the fact that a machine olfaction system as versatile, universal and broadband as human nose and human tongue may not be feasible in the decades to come. But application specific solutions may definitely be demonstrated and commercialized by modulation in sensor design and fine-tuning the soft computing solutions. This chapter deals with theory, developments of E-Nose and E-Tongue technology and their applications. Also a succinct account of future trends of R&D efforts in this field with an objective of establishing co-relation between machine olfaction and human perception has been included.

A theory of electron baths: One-electron system dynamics

International Nuclear Information System (INIS)

McDowell, H.K.

1992-01-01

The second-quantized, many-electron, atomic, and molecular Hamiltonian is partitioned both by the identity or labeling of the spin orbitals and by the dynamics of the spin orbitals into a system coupled to a bath. The electron bath is treated by a molecular time scale generalized Langevin equation approach designed to include one-electron dynamics in the system dynamics. The bath is formulated as an equivalent chain of spin orbitals through the introduction of equivalent-chain annihilation and creation operators. Both the dynamics and the quantum grand canonical statistical properties of the electron bath are examined. Two versions for the statistical properties of the bath are pursued. Using a weak bath assumption, a bath statistical average is defined which allows one to achieve a reduced dynamics description of the electron system which is coupled to the electron bath. In a strong bath assumption effective Hamiltonians are obtained which reproduce the dynamics of the bath and which lead to the same results as found in the weak bath assumption. The effective (but exact) Hamiltonian is found to be a one-electron Hamiltonian. A reduced dynamics equation of motion for the system population matrix is derived and found to agree with a previous version. This equation of motion is useful for studying electron transfer in the system when coupled to an electron bath

Treatment of foods with 'soft-electrons' (low-energy electrons)

International Nuclear Information System (INIS)

Hayashi, Toru; Todoriki, Setsuko

2003-01-01

Electrons with energies of 300 keV or lower were defined as soft-electrons'. Soft-electrons can eradicate microorganisms residing on the surface of grains, pulses, spices, dehydrated vegetables, tea leaves and seeds, and reduce their microbial loads to levels lower than 10 CFU/g with little quality deterioration. Soft-electrons can inactivate insect pests infesting grains and pulses and inhibit sprouting of potatoes. (author)

Appalachian hardwood stump sprouts are potential sawlog crop trees. Research note NE-299. [Oak, maple, linden, cherry trees

Energy Technology Data Exchange (ETDEWEB)

Lanson, N.I.

1976-01-01

Dbh and height of 8- and 12-year-old coppice shoots and the number of live shoots were recorded for 736 stumps at least 12 inches in diameter of Liriodendron tulipifera, Prunus serotina, Quercus rubra, Acer rubrum, and Tilia americana in north-central West Virgina. Of the 8-year-old shoots, T. americana had the greatest number of live stems/stump (16.8) and the greatest number of potential crop trees (dominant or co-dominant shoots attached to the stump not more than 6 inches above the ground), averaging 2.5 stems/stump. The average numbers of potential crop trees/stump were similar at 8 and 12 year. At 12 years, at least 88% of stumps of each species had at least one stem of groundline origin with no forks below 25 feet were 84% for L. tulipifera, 59% for Q rubra, 73% for A. rubrum, and 65% for P. Serotina.

Antimicrobial Activity Investigation on Wuyiencin Fractions of Different Polarity

Directory of Open Access Journals (Sweden)

Zengjie Cui

2010-04-01

Full Text Available The aim of this study was to evaluate the antimicrobial activity of Wuyiencin fractions with different polarities against six indicator microorganisms: Rhodotorula rubra, Bacillus subtilis, Bacillus megaterium, Escherichia coli, Cladosporium fulvum and Staphylococcus aureus. The fermentation broth of Wuyiencin was submitted to AB-8 macroporous adsorptive resin and fractionated with solvents of different polarity. The fraction eluted with water had remarkably antimicrobial activity against all the microorganisms investigated except for C. fulvum and S. aureus (MIC ≤ 0.0625 mg/mL, probably due to the presence of active components. The fraction eluted with methanol showed potential antimicrobial activity against all the test microorganisms except for R.rubra, with MIC values of0.5 and 2 mg/mL. In conclusion, fractions eluted with water and methanol, respectively, represent the main active-part of Wuyiencin, and could be emphasized for agricultural applications in the future.

Compact femtosecond electron diffractometer with 100 keV electron bunches approaching the single-electron pulse duration limit

International Nuclear Information System (INIS)

Waldecker, Lutz; Bertoni, Roman; Ernstorfer, Ralph

2015-01-01

We present the design and implementation of a highly compact femtosecond electron diffractometer working at electron energies up to 100 keV. We use a multi-body particle tracing code to simulate electron bunch propagation through the setup and to calculate pulse durations at the sample position. Our simulations show that electron bunches containing few thousands of electrons per bunch are only weakly broadened by space-charge effects and their pulse duration is thus close to the one of a single-electron wavepacket. With our compact setup, we can create electron bunches containing up to 5000 electrons with a pulse duration below 100 fs on the sample. We use the diffractometer to track the energy transfer from photoexcited electrons to the lattice in a thin film of titanium. This process takes place on the timescale of few-hundred femtoseconds and a fully equilibrated state is reached within 1 ps

Electron backscattering for process control in electron beam welding

International Nuclear Information System (INIS)

Ardenne, T. von; Panzer, S.

1983-01-01

A number of solutions to the automation of electron beam welding is presented. On the basis of electron backscattering a complex system of process control has been developed. It allows an enlarged imaging of the material's surface, improved adjustment of the beam focusing and definite focus positioning. Furthermore, both manual and automated positioning of the electron beam before and during the welding process has become possible. Monitoring of the welding process for meeting standard welding requirements can be achieved with the aid of a control quantity derived from the results of electronic evaluation of the high-frequency electron backscattering

Electron transfer reactions

CERN Document Server

Cannon, R D

2013-01-01

Electron Transfer Reactions deals with the mechanisms of electron transfer reactions between metal ions in solution, as well as the electron exchange between atoms or molecules in either the gaseous or solid state. The book is divided into three parts. Part 1 covers the electron transfer between atoms and molecules in the gas state. Part 2 tackles the reaction paths of oxidation states and binuclear intermediates, as well as the mechanisms of electron transfer. Part 3 discusses the theories and models of the electron transfer process; theories and experiments involving bridged electron transfe

Understand electronics

CERN Document Server

Bishop, Owen

2013-01-01

Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

Electronic Commerce

OpenAIRE

Slavko Đerić

2016-01-01

Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks...

Photon and electron collimator effects on electron output and abutting segments in energy modulated electron therapy

International Nuclear Information System (INIS)

Olofsson, Lennart; Karlsson, Magnus G.; Karlsson, Mikael

2005-01-01

In energy modulated electron therapy a large fraction of the segments will be arranged as abutting segments where inhomogeneities in segment matching regions must be kept as small as possible. Furthermore, the output variation between different segments should be minimized and must in all cases be well predicted. For electron therapy with add-on collimators, both the electron MLC (eMLC) and the photon MLC (xMLC) contribute to these effects when an xMLC tracking technique is utilized to reduce the x-ray induced leakage. Two add-on electron collimator geometries have been analyzed using Monte Carlo simulations: One isocentric eMLC geometry with an isocentric clearance of 35 cm and air or helium in the treatment head, and one conventional proximity geometry with a clearance of 5 cm and air in the treatment head. The electron fluence output for 22.5 MeV electrons is not significantly affected by the xMLC if the shielding margins are larger than 2-3 cm. For small field sizes and 9.6 MeV electrons, the isocentric design with helium in the treatment head or shielding margins larger than 3 cm is needed to avoid a reduced electron output. Dose inhomogeneity in the matching region of electron segments is, in general, small when collimator positions are adjusted to account for divergence in the field. The effect of xMLC tracking on the electron output can be made negligible while still obtaining a substantially reduced x-ray leakage contribution. Collimator scattering effects do not interfere significantly when abutting beam techniques are properly applied

Equation satisfied by electron-electron mutual Coulomb repulsion energy density functional

OpenAIRE

Joubert, Daniel P.

2011-01-01

The electron-electron mutual Coulomb repulsion energy density functional satisfies an equation that links functionals and functional derivatives at N-electron and (N-1)-electron densities for densities determined from the same adiabatic scaled external potential for the N-electron system.

Electronic Publishing.

Science.gov (United States)

Lancaster, F. W.

1989-01-01

Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

Modification of calcite crystal growth by abalone shell proteins: an atomic force microscope study.

OpenAIRE

Walters, D A; Smith, B L; Belcher, A M; Paloczi, G T; Stucky, G D; Morse, D E; Hansma, P K

1997-01-01

A family of soluble proteins from the shell of Haliotis rufescens was introduced over a growing calcite crystal being scanned in situ by an atomic force microscope (AFM). Atomic step edges on the crystal surface were altered in shape and speed of growth by the proteins. Proteins attached nonuniformly to the surface, indicating different interactions with crystallographically different step edges. The observed changes were consistent with the habit modification induced by this family of protei...

Manipulations of adult density and juvenile habitat quality in Northern Abalone stock restoration

OpenAIRE

DeFreitas, Bart Andre

2005-01-01

Wild abalone populations throughout the world have declined dramatically over the past 40 years due primarily to market demands for the mollusc's edible foot. Northern abalone (Haliotis kamtschatkana), the only abalone species occurring in British Columbia (B.C.), is widely thought to be threatened by potential population collapse as a result of low adult densities that impair reproductive potential. This study examined the hypothesis that the abundance of wild northern abalone populations ar...

Innate resistance of New Zealand paua to abalone viral ganglioneuritis.

Science.gov (United States)

Corbeil, Serge; McColl, Kenneth A; Williams, Lynette M; Slater, Joanne; Crane, Mark St J

2017-06-01

The susceptibility of New Zealand paua (Haliotis iris) to infection by abalone herpesvirus (Haliotid herpesvirus 1; HaHV) and to the disease abalone viral ganglioneuritis (AVG) was determined. Infection challenges performed by intra-muscular injection and by immersion in infectious water containing HaHV demonstrated that New Zealand paua were highly resistant to infection by Haliotid herpesvirus 1 and were fully resistant to the disease AVG. Copyright © 2017 Elsevier Inc. All rights reserved.

Syringe-injectable electronics.

Science.gov (United States)

Liu, Jia; Fu, Tian-Ming; Cheng, Zengguang; Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M

2015-07-01

Seamless and minimally invasive three-dimensional interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating the syringe injection (and subsequent unfolding) of sub-micrometre-thick, centimetre-scale macroporous mesh electronics through needles with a diameter as small as 100 μm. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with >90% device yield. We demonstrate several applications of syringe-injectable electronics as a general approach for interpenetrating flexible electronics with three-dimensional structures, including (1) monitoring internal mechanical strains in polymer cavities, (2) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (3) in vivo multiplexed neural recording. Moreover, syringe injection enables the delivery of flexible electronics through a rigid shell, the delivery of large-volume flexible electronics that can fill internal cavities, and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics.

Electronic excitation of Na atom by electron impact

International Nuclear Information System (INIS)

Bielschowsky, C.E.; Souza, G.G.B. de; Lucas, C.A.; Nogueira, J.C.

1988-01-01

Electronic excitation of the 3s-3p transition in the Na atom was studied by intermediate energy electron impact spectroscopy. Differential Cross Sections (DCS) and Generalized Oscillator Strenghts (GOS) were determined experimentally for 1 KeV electrons. Theoretical results within the First Born Approximation as well as Glauber theory, were also performed. (A.C.A.S.) [pt

Highly efficient electron gun with a single-atom electron source

International Nuclear Information System (INIS)

Ishikawa, Tsuyoshi; Urata, Tomohiro; Cho, Boklae; Rokuta, Eiji; Oshima, Chuhei; Terui, Yoshinori; Saito, Hidekazu; Yonezawa, Akira; Tsong, Tien T.

2007-01-01

The authors have demonstrated highly collimated electron-beam emission from a practical electron gun with a single-atom electron source; ∼80% of the total emission current entered the electron optics. This ratio was two or three orders of magnitude higher than those of the conventional electron sources such as a cold field emission gun and a Zr/O/W Schottky gun. At the pressure of less than 1x10 -9 Pa, the authors observed stable emission of 20 nA, which generates the specimen current of 5 pA required for scanning electron microscopes

Electron-electron interaction in p-SiGe/Ge quantum wells

International Nuclear Information System (INIS)

Roessner, Benjamin; Kaenel, Hans von; Chrastina, Daniel; Isella, Giovanni; Batlogg, Bertram

2005-01-01

The temperature dependent magnetoresistance of high mobility p-SiGe/Ge quantum wells is studied with hole densities ranging from 1.7 to 5.9 x 10 11 cm -2 . At magnetic fields below the onset of quantum oscillations that reflect the high mobility values (up to 75000 cm 2 /Vs), we observe the clear signatures of electron-electron interaction. We compare our experiment with the theory of electron-electron interaction including the Zeeman band splitting. The observed magnetoresistance is well explained as a superposition of band structure induced positive magnetoresistance and the negative magntoresistance due to the electron-electron interaction effect

Electron-electron interactions in disordered systems

CERN Document Server

Efros, AL

1985-01-01

``Electron-Electron Interactions in Disordered Systems'' deals with the interplay of disorder and the Coulomb interaction. Prominent experts give state-of-the-art reviews of the theoretical and experimental work in this field and make it clear that the interplay of the two effects is essential, especially in low-dimensional systems.

Narrow electron injector for ballistic electron spectroscopy

International Nuclear Information System (INIS)

Kast, M.; Pacher, C.; Strasser, G.; Gornik, E.

2001-01-01

A three-terminal hot electron transistor is used to measure the normal energy distribution of ballistic electrons generated by an electron injector utilizing an improved injector design. A triple barrier resonant tunneling diode with a rectangular transmission function acts as a narrow (1 meV) energy filter. An asymmetric energy distribution with its maximum on the high-energy side with a full width at half maximum of ΔE inj =10 meV is derived. [copyright] 2001 American Institute of Physics

Temperature Dependence of the Spin-Hall Conductivity of a Two-Dimensional Impure Rashba Electron Gas in the Presence of Electron-Phonon and Electron-Electron Interactions

Science.gov (United States)

Yavari, H.; Mokhtari, M.; Bayervand, A.

2015-03-01

Based on Kubo's linear response formalism, temperature dependence of the spin-Hall conductivity of a two-dimensional impure (magnetic and nonmagnetic impurities) Rashba electron gas in the presence of electron-electron and electron-phonon interactions is analyzed theoretically. We will show that the temperature dependence of the spin-Hall conductivity is determined by the relaxation rates due to these interactions. At low temperature, the elastic lifetimes ( and are determined by magnetic and nonmagnetic impurity concentrations which are independent of the temperature, while the inelastic lifetimes ( and related to the electron-electron and electron-phonon interactions, decrease when the temperature increases. We will also show that since the spin-Hall conductivity is sensitive to temperature, we can distinguish the intrinsic and extrinsic contributions.

Analytical local electron-electron interaction model potentials for atoms

International Nuclear Information System (INIS)

Neugebauer, Johannes; Reiher, Markus; Hinze, Juergen

2002-01-01

Analytical local potentials for modeling the electron-electron interaction in an atom reduce significantly the computational effort in electronic structure calculations. The development of such potentials has a long history, but some promising ideas have not yet been taken into account for further improvements. We determine a local electron-electron interaction potential akin to those suggested by Green et al. [Phys. Rev. 184, 1 (1969)], which are widely used in atom-ion scattering calculations, electron-capture processes, and electronic structure calculations. Generalized Yukawa-type model potentials are introduced. This leads, however, to shell-dependent local potentials, because the origin behavior of such potentials is different for different shells as has been explicated analytically [J. Neugebauer, M. Reiher, and J. Hinze, Phys. Rev. A 65, 032518 (2002)]. It is found that the parameters that characterize these local potentials can be interpolated and extrapolated reliably for different nuclear charges and different numbers of electrons. The analytical behavior of the corresponding localized Hartree-Fock potentials at the origin and at long distances is utilized in order to reduce the number of fit parameters. It turns out that the shell-dependent form of Green's potential, which we also derive, yields results of comparable accuracy using only one shell-dependent parameter

Extracting electron backscattering coefficients from backscattered electron micrographs

International Nuclear Information System (INIS)

Zupanic, F.

2010-01-01

Electron backscattering micrographs possess the so-called Z-contrast, carrying information about the chemical compositions of phases present in microstructures. The intensity at a particular point in the backscattered electron micrograph is proportional to the signal detected at a corresponding point in the scan raster, which is, in turn, proportional to the electron backscattering coefficient of a phase at that point. This article introduces a simple method for extracting the electron backscattering coefficients of phases present in the microstructure, from the backscattered electron micrographs. This method is able to convert the micrograph's greyscale to the backscattering-coefficient-scale. The prerequisite involves the known backscattering coefficients for two phases in the micrograph. In this way, backscattering coefficients of other phases can be determined. The method is unable to determine the chemical compositions of phases or the presence of an element only from analysing the backscattered electron micrograph. Nevertheless, this method was found to be very powerful when combined with energy dispersive spectroscopy, and the calculations of backscattering coefficients. - Research Highlights: →A simple method for extracting the electron backscattering coefficients →The prerequisite is known backscattering coefficients for two phases →The information is complementary to the EDS-results. →This method is especially useful when a phase contains a light element (H, Li, Be, and B)

PIC simulation of the electron-ion collision effects on suprathermal electrons

International Nuclear Information System (INIS)

Wu Yanqing; Han Shensheng

2000-01-01

The generation and transportation of suprathermal electrons are important to both traditional ICF scheme and 'Fast Ignition' scheme. The author discusses the effects of electron-ion collision on the generation and transportation of the suprathermal electrons by parametric instability. It indicates that the weak electron-ion term in the PIC simulation results in the enhancement of the collisional absorption and increase of the hot electron temperature and reduction in the maximum electrostatic field amplitude while wave breaking. Therefore the energy and distribution of the suprathermal electrons are changed. They are distributed more close to the phase velocity of the electrostatic wave than the case without electron-ion collision term. The electron-ion collision enhances the self-consistent field and impedes the suprathermal electron transportation. These factors also reduce the suprathermal electron energy. In addition, the authors discuss the effect of initial condition on PIC simulation to ensure that the results are correct

Spin Relaxation in GaAs: Importance of Electron-Electron Interactions

Directory of Open Access Journals (Sweden)

Gionni Marchetti

2014-04-01

Full Text Available We study spin relaxation in n-type bulk GaAs, due to the Dyakonov–Perel mechanism, using ensemble Monte Carlo methods. Our results confirm that spin relaxation time increases with the electronic density in the regime of moderate electronic concentrations and high temperature. We show that the electron-electron scattering in the non-degenerate regime significantly slows down spin relaxation. This result supports predictions by Glazov and Ivchenko. Most importantly, our findings highlight the importance of many-body interactions for spin dynamics: we show that only by properly taking into account electron-electron interactions within the simulations, results for the spin relaxation time—with respect to both electron density and temperature—will reach good quantitative agreement with corresponding experimental data. Our calculations contain no fitting parameters.

Secondary mineralization in carious lesions of human dentin. Electron-probe, electron microscope, and electron diffraction studies

Energy Technology Data Exchange (ETDEWEB)

Ogiwara, H [Tokyo Dental Coll. (Japan)

1975-02-01

Dentinal carious lesions having a remineralized surface layer were studied by means electron-probe microanalysis, electron microscopy, electron diffraction. As the results of electron-probe study, F, Mg, and Na were found to be distributed mainly in the remineralized surface layer and S in the decalcified region where decreases in Ca, P, and Mg concentration were usually observed. The decrease in Mg concentration always started earlier than that of Ca and P concentration. Electron microscope and electron diffraction studies revealed that apatic crystals in the remineralized surface layer were much larger than those in the intact dentin. Although they were less conspicuous, crystals in the decalcified region also were larger than those in the intact region. Dentinal tubules, occluded by many crystals, were frequently seen during the observations. Crystals in the tubules varied in morphology, showing granular, needle, rhomboid, and tabular shapes. By means of electron diffraction, the granular- or needle-shaped crystals were identified as apatite and the rhomboid-shaped crystals as whitlockite. Some of the tabular-shaped crystals appeared to be cotacalcium phosphate.

Electronic components

CERN Document Server

Colwell, Morris A

1976-01-01

Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

Ion- and electron-acoustic solitons in two-electron temperature space plasmas

International Nuclear Information System (INIS)

Lakhina, G. S.; Kakad, A. P.; Singh, S. V.; Verheest, F.

2008-01-01

Properties of ion- and electron-acoustic solitons are investigated in an unmagnetized multicomponent plasma system consisting of cold and hot electrons and hot ions using the Sagdeev pseudopotential technique. The analysis is based on fluid equations and the Poisson equation. Solitary wave solutions are found when the Mach numbers exceed some critical values. The critical Mach numbers for the ion-acoustic solitons are found to be smaller than those for electron-acoustic solitons for a given set of plasma parameters. The critical Mach numbers of ion-acoustic solitons increase with the increase of hot electron temperature and the decrease of cold electron density. On the other hand, the critical Mach numbers of electron-acoustic solitons increase with the increase of the cold electron density as well as the hot electron temperature. The ion-acoustic solitons have positive potentials for the parameters considered. However, the electron-acoustic solitons have positive or negative potentials depending whether the fractional cold electron density with respect to the ion density is greater or less than a certain critical value. Further, the amplitudes of both the ion- and electron-acoustic solitons increase with the increase of the hot electron temperature. Possible application of this model to electrostatic solitary waves observed on the auroral field lines by the Viking spacecraft is discussed

Virulence, sporulation, and elicitin production in three clonal lineages of Phytophthora ramorum

Science.gov (United States)

Phytophthora ramorum populations are clonal and consist of three lineages. Recent studies have shown that the clonal lineages may have varying degrees of aggressiveness on some host species, such as Quercus rubra. In this study, we examined virulence, sporulation and elicitin production of five P. ...

Aluminum solubility and mobility in relation to organic carbon in surface soils affected by six tree species of the northeastern United States

NARCIS (Netherlands)

Dijkstra, F.A.; Fitzhugh, R.D.

2003-01-01

We compared Al solubility and mobility in surface soils among six tree species (sugar maple [Acer saccharum], white ash [Fraxinus americana], red maple [Acer rubrum, L.], American beech [Fagus grandifolia, Ehrh.], red oak [Quercus rubra, L.], and hemlock [Tsuga canadensis, Carr.]) in a mixed

Spatial variation in population dynamics of Sitka mice in floodplain forests.

Science.gov (United States)

T.A. Hanley; J.C. Barnard

1999-01-01

Population dynamics and demography of the Sitka mouse, Peromyscus keeni sitkensis, were studied by mark-recapture live-trapping over a 4-year period in four floodplain and upland forest habitats: old-growth Sitka spruce (Picea sitchensis) floodplain; red alder (Alnus rubra) floodplain; beaver-pond...

Developing Biomass Equations for Western Hemlock and Red Alder Trees in Western Oregon Forests

Science.gov (United States)

Krishna Poudel; Hailemariam Temesgen

2016-01-01

Biomass estimates are required for reporting carbon, assessing feedstock availability, and assessing forest fire threat. We developed diameter- and height-based biomass equations for Western hemlock (Tsuga heterophylla (Raf.) Sarg.) and red alder (Alnus rubra Bong.) trees in Western Oregon. A system of component biomass...

Search of yeast-like fungi in some lakes of the Tucholski Landscape Park (NW Poland

Directory of Open Access Journals (Sweden)

Anna Rózga

2014-08-01

Full Text Available The occurrence of pathogenic yeast-like fungi was determined in the catchment of the Suska and Raciąska Struga. Fourteen strains of fungi from 3 genera were isolated: Candida inconspicua, C. lambica, C. glabrata, Rhodotorula rubra, Rh. glutinls and Trichosporon capitatum.

Diffusive scattering of electrons by electron holes around injection fronts

Science.gov (United States)

Vasko, I. Y.; Agapitov, O. V.; Mozer, F. S.; Artemyev, A. V.; Krasnoselskikh, V. V.; Bonnell, J. W.

2017-03-01

Van Allen Probes have detected nonlinear electrostatic spikes around injection fronts in the outer radiation belt. These spikes include electron holes (EH), double layers, and more complicated solitary waves. We show that EHs can efficiently scatter electrons due to their substantial transverse electric fields. Although the electron scattering driven by EHs is diffusive, it cannot be evaluated via the standard quasi-linear theory. We derive analytical formulas describing local electron scattering by a single EH and verify them via test particle simulations. We show that the most efficiently scattered are gyroresonant electrons (crossing EH on a time scale comparable to the local electron gyroperiod). We compute bounce-averaged diffusion coefficients and demonstrate their dependence on the EH spatial distribution (latitudinal extent and spatial filling factor) and individual EH parameters (amplitude of electrostatic potential, velocity, and spatial scales). We show that EHs can drive pitch angle scattering of ≲5 keV electrons at rates 10-2-10-4 s-1 and, hence, can contribute to electron losses and conjugated diffuse aurora brightenings. The momentum and pitch angle scattering rates can be comparable, so that EHs can also provide efficient electron heating. The scattering rates driven by EHs at L shells L ˜ 5-8 are comparable to those due to chorus waves and may exceed those due to electron cyclotron harmonics.

Pseudogap in the Eliashberg approach based on electron-phonon and electron-electron-phonon interaction

Energy Technology Data Exchange (ETDEWEB)

Szczesniak, R. [Institute of Physics, Czestochowa University of Technology (Poland); Institute of Physics, Jan Dlugosz University in Czestochowa (Poland); Durajski, A.P.; Duda, A.M. [Institute of Physics, Czestochowa University of Technology (Poland)

2017-04-15

The properties of the superconducting and the anomalous normal state were described by using the Eliashberg method. The pairing mechanism was reproduced with the help of the Hamiltonian, which models the electron-phonon and the electron-electron-phonon interaction (EEPh). The set of the Eliashberg equations, which determines the order parameter function (φ), the wave function renormalization factor (Z), and the energy shift function (χ), was derived. It was proven that for the sufficiently large values of the EEPh potential, the doping dependence of the order parameter (φ/Z) has the analogous course to that observed experimentally in cuprates. The energy gap in the electron density of states is induced by Z and χ - the contribution from φ is negligible. The electron density of states possesses the characteristic asymmetric form and the pseudogap is observed above the critical temperature. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Carbon Nanotube Electron Gun

Science.gov (United States)

Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

2013-01-01

An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

Molecular electron affinities

International Nuclear Information System (INIS)

Fukuda, E.K.

1983-01-01

Molecular electron affinities have historically been difficult quantities to measure accurately. These difficulties arise from differences in structure between the ion and neutral as well as the existence of excited negative ion states. To circumvent these problems, relative electron affinities were determined in this dissertation by studying equilibrium electron transfer reactions using a pulsed ion cyclotron resonance (ICR) spectrometer. Direct measurement of ion and neutral concentrations for reactions of the general type, A - + B = B - + A, allow calculation of the equilibrium constant and, therefore, the free energy change. The free energy difference is related to the difference in electron affinities between A and B. A relative electron affinity scale covering a range of about 45 kcal/mol was constructed with various substituted p-benzoquinones, nitrobenzenes, anhydrides, and benzophenones. To assign absolute electron affinities, various species with accurately known electron affinities are tied to the scale via ion-cyclotron double resonance bracketing techniques. After the relative scale is anchored to these species with well-known electron affinities, the scale is then used as a check on other electron affinity values as well as generating new electron affinity values. Many discrepancies were found between the electron affinities measured using the ICR technique and previous literature determinations

Nonambipolar electron source

International Nuclear Information System (INIS)

Longmier, B.; Baalrud, S.; Hershkowitz, N.

2006-01-01

A radio frequency (rf) plasma-based electron source that does not rely on electron emission at a cathode surface has been constructed. All of the random electron flux incident on an exit aperture is extracted through an electron sheath resulting in total nonambipolar flow within the device when the ratio of the ion loss area to the electron loss area is approximately equal to the square root of the ratio of the ion mass to the electron mass, and the ion sheath potential drop at the chamber walls is much larger than T e /e. The nonambipolar electron source (NES) has an axisymmetric magnetic field of 100 G at the extraction aperture that results in a uniform plasma potential across the aperture, allowing the extraction of all the incident electron flux without the use of grids. A prototype NES has produced 15 A of continuous electron current, using 15 SCCM (SCCM denotes cubic centimeter per minute at STP) Ar, 1200 W rf power at 13.56 MHz, and 6 times gas utilization. Alternatively 8 A of electron current can be produced, using 3 SCCM Ar at 1200 W rf and 20 times gas utilization. NES could replace hollow cathode electron sources in a wide variety of applications

Electron-plasmon model in the electron liquid theory

Directory of Open Access Journals (Sweden)

M.V.Vavrukh

2005-01-01

Full Text Available Here we propose an accurate approach to the description of the electron liquid model in the electron and plasmon terms. Our ideas in the present paper are close to the conception of the collective variables which was developed in the papers of Bohm and Pines. However we use another body of mathematics in the transition to the expanded space of variable particles and plasmons realized by the transition operator. It is evident that in the Random Phase Approximation (RPA, the model which consists of two interactive subsystems of electrons and plasmons is equivalent to the electron liquid model with Coulomb interaction.

Polymer electronics

CERN Document Server

Hsin-Fei, Meng

2013-01-01

Polymer semiconductor is the only semiconductor that can be processed in solution. Electronics made by these flexible materials have many advantages such as large-area solution process, low cost, and high performance. Researchers and companies are increasingly dedicating time and money in polymer electronics. This book focuses on the fundamental materials and device physics of polymer electronics. It describes polymer light-emitting diodes, polymer field-effect transistors, organic vertical transistors, polymer solar cells, and many applications based on polymer electronics. The book also disc

A direct electron detector for time-resolved MeV electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Vecchione, T.; Denes, P.; Jobe, R. K.; Johnson, I. J.; Joseph, J. M.; Li, R. K.; Perazzo, A.; Shen, X.; Wang, X. J.; Weathersby, S. P.; Yang, J.; Zhang, D.

2017-03-01

The introduction of direct electron detectors enabled the structural biology revolution of cryogenic electron microscopy. Direct electron detectors are now expected to have a similarly dramatic impact on time-resolved MeV electron microscopy, particularly by enabling both spatial and temporal jitter correction. Here we report on the commissioning of a direct electron detector for time-resolved MeV electron microscopy. The direct electron detector demonstrated MeV single electron sensitivity and is capable of recording megapixel images at 180 Hz. The detector has a 15-bit dynamic range, better than 30-μmμm spatial resolution and less than 20 analogue-to-digital converter count RMS pixel noise. The unique capabilities of the direct electron detector and the data analysis required to take advantage of these capabilities are presented. The technical challenges associated with generating and processing large amounts of data are also discussed.

Coherent Electron Focussing in a Two-Dimensional Electron Gas.

NARCIS (Netherlands)

Houten, H. van; Wees, B.J. van; Mooij, J.E.; Beenakker, C.W.J.; Williamson, J.G.; Foxon, C.T.

1988-01-01

The first experimental realization of ballistic point contacts in a two-dimensional electron gas for the study of transverse electron focussing by a magnetic field is reported. Multiple peaks associated with skipping orbits of electrons reflected specularly by the channel boundary are observed. At

A study on the secondary electrons in a clinical electron beam

International Nuclear Information System (INIS)

Krithivas, G.; Rao, S.N.

1989-01-01

The central axis dose of a 12 MeV clinical electron beam is investigated in terms of an axial component due to primary electrons in the central ray and a lateral component due to secondary electrons originating from multiple scattering of electrons in the off-axis rays. To this effect secondary electron fluence measurements in a polystyrene medium irradiated with a collimated beam are made with a sensitive diode detector. This leads to a construction of secondary electron depth-dose profiles for beam sizes of diameters ranging from 1.7 to 17.4 cm. The results indicate that the lateral electrons account for 25% of the dose in the therapeutic region. For these electrons, the depth of dose maximum is correlated with diffusion depth and maximum lateral excursion in the medium. Dose component due to backscatter electrons at depths is also investigated using a thin-window parallel-plate ion chamber. The role of lateral and backscatter electrons in characterising central axis per cent depth-dose is discussed. (author)

Electronics for dummies

CERN Document Server

Shamieh

2015-01-01

Explore the basic concepts of electronics, build your electronics workbench, and begin creating fun electronics projects right away! Electronics For Dummies, 3rd Edition is your guide to the world of electronics. Spanning circuitry, wiring, robotics, transmitters, amplifiers, and more, this book demystifies electricity basics and beyond. The third edition offers new content revised to reflect the latest advancements in the electronics field, and it offers full color project examples to spark your creativity and inspire you to put your new skills to use! Packed with projects that can be comple

Electron holography

CERN Document Server

Tonomura, Akira

1993-01-01

Holography was devised for breaking through the resolution limit of electron microscopes The advent of a "coherent" field emission electron beam has enabled the use of Electron Holography in various areas of magnetic domain structures observation, fluxon observation in superconductors, and fundamental experiments in physics which have been inaccessible using other techniques After examining the fundamentals of electron holography and its applications to the afore mentioned fields, a detailed discussion of the Aharonov-Bohm effect and the related experiments is presented Many photographs and illustrations are included to elucidate the text

Comprehensive analysis of electron correlations in three-electron atoms

International Nuclear Information System (INIS)

Morishita, T.; Lin, C.D.

1999-01-01

We study the electron correlations in singly, doubly, and triply excited states of a three-electron atom. While electron correlation in general is weak for singly excited states, correlation plays major roles in determining the characteristics of doubly and triply excited states. Using the adiabatic approximation in hyperspherical coordinates, we show that the distinction between singly, doubly, and triply excited states is determined by the radial correlations, while finer distinctions within doubly or triply excited states lie in the angular correlations. Partial projections of the body-fixed frame wave functions are used to demonstrate the characteristic nodal surfaces which provide clues to the energy ordering of the states. We show that doubly excited states of a three-electron atom exhibit correlations that are similar to the doubly excited states of a two-electron atom. For the triply excited states, we show that the motion of the three electrons resemble approximately that of a symmetric top. copyright 1999 The American Physical Society

Advanced electron beam techniques

International Nuclear Information System (INIS)

Hirotsu, Yoshihiko; Yoshida, Yoichi

2007-01-01

After 100 years from the time of discovery of electron, we now have many applications of electron beam in science and technology. In this report, we review two important applications of electron beam: electron microscopy and pulsed-electron beam. Advanced electron microscopy techniques to investigate atomic and electronic structures, and pulsed-electron beam for investigating time-resolved structural change are described. (author)

Effects of electron-electron interactions on electronic transport in disordered systems

International Nuclear Information System (INIS)

Foley, Simon Timothy

2002-01-01

This thesis is concerned with the role of electron-electron interactions on electronic transport in disordered systems. We first consider a novel non-linear sigma model in order to microscopically treat the effects of disorder and electronic interaction. We successfully reproduce the perturbative results for the zero-bias anomaly and the interaction correction to the conductivity in a weakly disordered system, and discuss possible directions for future work. Secondly we consider the fluctuations of the dephasing rate for a closed diffusive and quantum dot system. Using the Keldysh technique we derive an expression for the inelastic scattering rate with which we self-consistently obtain the fluctuations in the dephasing rate. For the diffusive regime we find the relative fluctuations is given by F ∼ (L φ /L) 2 /g 2 , where g is the dimensionless conductance, L φ is the dephasing length and L is the sample size. For the quantum dot regime we find a perturbative divergence due to the presence of the zero mode. By mapping divergent diagrams to those for the two-level correlation function, we conjecture the existence of an exact relation between the two. Finally we discuss the consequences of this relation. (author)

Characteristics of trapped electrons and electron traps in single crystals

International Nuclear Information System (INIS)

Budzinski, E.E.; Potter, W.R.; Potienko, G.; Box, H.C.

1979-01-01

Two additional carbohydrates are reported whose crystal structures trap electrons intermolecularly in single crystals x irradiated at low temperature, namely sucrose and rhamnose. Five carbohydrate and polyhydroxy compounds are now known which exhibit this phenomenon. The following characteristics of the phenomenon were investigated: (1) the hyperfine couplings of the electron with protons of the polarized hydroxy groups forming the trap; (2) the distances between these protons and the trapped electron; (3) the spin density of the electron at the protons and (4) the relative stabilities of the electron trapped in various crystal structures

Electron-electron scattering in linear transport in two-dimensional systems

DEFF Research Database (Denmark)

Hu, Ben Yu-Kuang; Flensberg, Karsten

1996-01-01

We describe a method for numerically incorporating electron-electron scattering in quantum wells for small deviations of the distribution function from equilibrium, within the framework of the Boltzmann equation. For a given temperature T and density n, a symmetric matrix needs to be evaluated only...... once, and henceforth it can be used to describe electron-electron scattering in any Boltzmann equation linear-response calculation for that particular T and n. Using this method, we calculate the distribution function and mobility for electrons in a quantum well, including full finite...

Terahertz Plasma Waves in Two Dimensional Quantum Electron Gas with Electron Scattering

International Nuclear Information System (INIS)

Zhang Liping

2015-01-01

We investigate the Terahertz (THz) plasma waves in a two-dimensional (2D) electron gas in a nanometer field effect transistor (FET) with quantum effects, the electron scattering, the thermal motion of electrons and electron exchange-correlation. We find that, while the electron scattering, the wave number along y direction and the electron exchange-correlation suppress the radiation power, but the thermal motion of electrons and the quantum effects can amplify the radiation power. The radiation frequency decreases with electron exchange-correlation contributions, but increases with quantum effects, the wave number along y direction and thermal motion of electrons. It is worth mentioning that the electron scattering has scarce influence on the radiation frequency. These properties could be of great help to the realization of practical THz plasma oscillations in nanometer FET. (paper)

Oblique electron cyclotron emission for electron distribution studies (invited)

International Nuclear Information System (INIS)

Preische, S.; Efthimion, P.C.; Kaye, S.M.

1997-01-01

Electron cyclotron emission (ECE) at an oblique angle to the magnetic field provides a means of probing the electron distribution function both in energy and physical space through changes in and constraints on the relativistic electron cyclotron resonance condition. Diagnostics based on this Doppler shifted resonance are able to study a variety of electron distributions through changes in the location of the resonance in physical or energy space accomplished by changes in the viewing angle and frequency, and the magnetic field. For the case of observation across a changing magnetic field, such as across the tokamak midplane, the constraint on the resonance condition for real solutions to the dispersion relation can constrain the physical location of optically thin emission. A new Oblique ECE diagnostic was installed and operated on the PBX-M tokamak for the study of energetic electrons during lower hybrid current drive. It has a view 33 degree with respect to perpendicular in the tokamak midplane, receives second harmonic X-mode emission, and is constrained to receive single pass emission by SiC viewing dumps on the tokamak walls. Spatial localization of optically thin emission from superthermal electrons (50 endash 100 keV) was obtained by observation of emission upshifted from a thermal cyclotron harmonic. The localized measurements of the electron energy distribution and the superthermal density profile made by this diagnostic demonstrate its potential to study the spatial transport of energetic electrons on fast magnetohydrodynamic time scales or anomalous diffusion time scales. Oblique ECE can also be used to study electron distributions that may have a slight deviation from a Maxwellian by localizing the emission in energy space. (Abstract Truncated)

Electron microscopy of boron carbide before and after electron irradiation

International Nuclear Information System (INIS)

Stoto, T.; Zuppiroli, L.; Beauvy, M.; Athanassiadis, T.

1984-06-01

The microstructure of boron carbide has been studied by electron microscopy and related to the composition of the material. After electron irradiations in an usual transmission electron microscope and in a high voltage electron microscope at different temperatures and fluxes no change of these microstructures have been observed but a sputtering of the surface of the samples, which has been studied quantitatively [fr

Electron Cyclotron Resonances in Electron Cloud Dynamics

International Nuclear Information System (INIS)

Celata, Christine; Celata, C.M.; Furman, Miguel A.; Vay, J.-L.; Yu, Jennifer W.

2008-01-01

We report a previously unknown resonance for electron cloud dynamics. The 2D simulation code 'POSINST' was used to study the electron cloud buildup at different z positions in the International Linear Collider positron damping ring wiggler. An electron equilibrium density enhancement of up to a factor of 3 was found at magnetic field values for which the bunch frequency is an integral multiple of the electron cyclotron frequency. At low magnetic fields the effects of the resonance are prominent, but when B exceeds ∼(2 pi mec/(elb)), with lb = bunch length, effects of the resonance disappear. Thus short bunches and low B fields are required for observing the effect. The reason for the B field dependence, an explanation of the dynamics, and the results of the 2D simulations and of a single-particle tracking code used to elucidate details of the dynamics are discussed

Role of electron-electron interactions in the RKKY theory of magnetism

International Nuclear Information System (INIS)

Cooke, J.F.

1978-10-01

The theory of magnetism in heavy rare earth metals is based on the RKKY theory. In this formalism the indirect exchange interaction between the local 4f spins is mediated by the conduction electrons. When carried to second order in the 4f-conduction electron interaction, traditional perturbation theory leads to a Heisenberg-like interaction between the local spins which depends on the electronic energy bands and 4f-conduction electron exchange matrix elements. This derivation neglects the detailed behavior of electron-electron interaction within the conduction band, which is known to be important in metallic systems. By using an equation of motion method, an expression for the inelastic neutron scattering cross-section has been derived which includes, in an approximate way, this electron-electron interaction. The results of this calculation indicate that spin-wave peaks can be broadened and shifted if the spin-wave band lies near the conduction electron Stoner continuum. The origin of this effect is similar to that found in itinerant electron systems where the spin-wave band actually intersects the Stoner continuum, resulting in the disappearance of the spin-wave mode

Role of electron-electron interactions in the RKKY theory of magnetism

International Nuclear Information System (INIS)

Cooke, J.F.

1979-01-01

The theory of magnetism in heavy rare earth metals is based on the RKKY theory. In this formalism the indirect exchange interaction between the local 4f spins is mediated by the conduction electrons. When carried to second order in the 4f-conduction electron interaction, traditional pertubation theory leads to a Heisenberg-like interaction between the local spins which depends on the electronic energy bands and 4f-conduction electron exchange matrix elements. This derivation neglects the detailed behavior of electron-electron interaction within the conduction band, which is known to be important in metallic systems. By using an equation of motion method, an expression for the inelastic neutron scattering cross-section has been derived which includes, in an approximate way, this electron-electron interaction. The results of this calculation indicate that spin-wave peaks can be broadened and shifted if the spin-wave band lies near the conduction electron Stoner continuum. The origin of this effect is similar to that found in itinerant electron systems where the spin-wave band actually intersects the Stoner continuum, resulting in the disappearance of the spin-wave mode

Electron acoustic solitary waves in unmagnetized two electron population dense plasmas

International Nuclear Information System (INIS)

Mahmood, S.; Masood, W.

2008-01-01

The electron acoustic solitary waves are studied in unmagnetized two population electron quantum plasmas. The quantum hydrodynamic model is employed with the Sagdeev potential approach to describe the arbitrary amplitude electron acoustic waves in a two electron population dense Fermi plasma. It is found that hot electron density hump structures are formed in the subsonic region in such type of quantum plasmas. The wave amplitude as well as the width of the soliton are increased with the increase of percentage presence of cold (thinly populated) electrons in a multicomponent quantum plasma. It is found that an increase in quantum diffraction parameter broadens the nonlinear structure. Furthermore, the amplitude of the nonlinear electron acoustic wave is found to increase with the decrease in Mach number. The numerical results are also presented to understand the formation of solitons in two electron population Fermi plasmas.

Advances in imaging and electron physics the scanning transmission electron microscope

CERN Document Server

Hawkes, Peter W

2009-01-01

Advances in Imaging and Electron Physics merges two long-running serials--Advances in Electronics and Electron Physics and Advances in Optical and Electron Microscopy. This series features extended articles on the physics of electron devices (especially semiconductor devices), particle optics at high and low energies, microlithography, image science and digital image processing, electromagnetic wave propagation, electron microscopy, and the computing methods used in all these domains.  This particular volume presents several timely articles on the scanning transmission electron microscope. Updated with contributions from leading international scholars and industry experts Discusses hot topic areas and presents current and future research trends Provides an invaluable reference and guide for physicists, engineers and mathematicians.

Attractive electron correlation in wide band gap semiconductors by electron-photon interaction

International Nuclear Information System (INIS)

Takeda, Hiroyuki; Yoshino, Katsumi

2004-01-01

We theoretically demonstrate attractive electron correlation in wide band gap semiconductors by electron-photon interaction. At low temperature, wavevectors of electromagnetic waves absorbed in wide band gap semiconductors cannot be neglected for wavevectors of electron waves; that is, electromagnetic waves affect the movements of electrons. In particular, attractive interaction occurs between two electrons when one electron changes from a valence band to a conduction band and the other electron changes from a conduction band to a valence band

Electronic Publishing or Electronic Information Handling?

Science.gov (United States)

Heck, A.

The current dramatic evolution in information technology is bringing major modifications in the way scientists communicate. The concept of 'electronic publishing' is too restrictive and has often different, sometimes conflicting, interpretations. It is thus giving way to the broader notion of 'electronic information handling' encompassing the diverse types of information, the different media, as well as the various communication methodologies and technologies. New problems and challenges result also from this new information culture, especially on legal, ethical, and educational grounds. The procedures for validating 'published material' and for evaluating scientific activities will have to be adjusted too. 'Fluid' information is becoming a common concept. Electronic publishing cannot be conceived without link to knowledge bases nor without intelligent information retrieval tools.

Theoretical study of the interplay of electron-electron interaction and disorder

International Nuclear Information System (INIS)

Brezini, A.; Behilil, S.

1988-10-01

A disordered Hubbard model with diagonal disorder is used to investigate the electron localization effects associated with both disorder and electron-electron interaction. Extensive results are reported on the ground state properties and compared to other theories. Two regimes have been found: when the electron-electron interaction u is greater than the disorder parameter w and when u < w. (author). 18 refs, 4 figs

Defining Electron Bifurcation in the Electron-Transferring Flavoprotein Family.

Science.gov (United States)

Garcia Costas, Amaya M; Poudel, Saroj; Miller, Anne-Frances; Schut, Gerrit J; Ledbetter, Rhesa N; Fixen, Kathryn R; Seefeldt, Lance C; Adams, Michael W W; Harwood, Caroline S; Boyd, Eric S; Peters, John W

2017-11-01

Electron bifurcation is the coupling of exergonic and endergonic redox reactions to simultaneously generate (or utilize) low- and high-potential electrons. It is the third recognized form of energy conservation in biology and was recently described for select electron-transferring flavoproteins (Etfs). Etfs are flavin-containing heterodimers best known for donating electrons derived from fatty acid and amino acid oxidation to an electron transfer respiratory chain via Etf-quinone oxidoreductase. Canonical examples contain a flavin adenine dinucleotide (FAD) that is involved in electron transfer, as well as a non-redox-active AMP. However, Etfs demonstrated to bifurcate electrons contain a second FAD in place of the AMP. To expand our understanding of the functional variety and metabolic significance of Etfs and to identify amino acid sequence motifs that potentially enable electron bifurcation, we compiled 1,314 Etf protein sequences from genome sequence databases and subjected them to informatic and structural analyses. Etfs were identified in diverse archaea and bacteria, and they clustered into five distinct well-supported groups, based on their amino acid sequences. Gene neighborhood analyses indicated that these Etf group designations largely correspond to putative differences in functionality. Etfs with the demonstrated ability to bifurcate were found to form one group, suggesting that distinct conserved amino acid sequence motifs enable this capability. Indeed, structural modeling and sequence alignments revealed that identifying residues occur in the NADH- and FAD-binding regions of bifurcating Etfs. Collectively, a new classification scheme for Etf proteins that delineates putative bifurcating versus nonbifurcating members is presented and suggests that Etf-mediated bifurcation is associated with surprisingly diverse enzymes. IMPORTANCE Electron bifurcation has recently been recognized as an electron transfer mechanism used by microorganisms to maximize

Effects of electron-electron interactions on the electron distribution function of a plasma in the presence of an external electric field

International Nuclear Information System (INIS)

Molinari, V.G.; Pizzio, F.; Spiga, G.

1979-01-01

The electron distribution function, the electron temperature and some transport parameters (electrical conductivity and energy flow coefficient) are obtained starting from the nonlinear Boltzmann equation for a plasma under the action of an external electric field. The Fokker-Planck approximation is used for electron-electron and electron-ion interactions. The effects of electron-electron collisions are studied for different values of collision frequencies and electric field. (author)

Electron-excited molecule interactions

International Nuclear Information System (INIS)

Christophorou, L.G.; Tennessee Univ., Knoxville, TN

1991-01-01

In this paper the limited but significant knowledge to date on electron scattering from vibrationally/rotationally excited molecules and electron scattering from and electron impact ionization of electronically excited molecules is briefly summarized and discussed. The profound effects of the internal energy content of a molecule on its electron attachment properties are highlighted focusing in particular on electron attachment to vibrationally/rotationally and to electronically excited molecules. The limited knowledge to date on electron-excited molecule interactions clearly shows that the cross sections for certain electron-molecule collision processes can be very different from those involving ground state molecules. For example, optically enhanced electron attachment studies have shown that electron attachment to electronically excited molecules can occur with cross sections 10 6 to 10 7 times larger compared to ground state molecules. The study of electron-excited molecule interactions offers many experimental and theoretical challenges and opportunities and is both of fundamental and technological significance. 54 refs., 15 figs

Variability of crossreactivity of IgE antibodies to group I and V allergens in eight grass pollen species

NARCIS (Netherlands)

van Ree, R.; Driessen, M. N.; van Leeuwen, W. A.; Stapel, S. O.; Aalberse, R. C.

1992-01-01

Crossreactivity to Dactylis glomerata, Festuca rubra, Phleum pratense, Anthoxanthum odoratum, Secale cereale, Zea mays, and Phragmites communis of IgE antibodies against Lol p I or Lol p V was investigated by means of RAST-inhibition. Within a group of sera the degree of crossreactivity was

Long-term above-ground biomass production in a red oak-pecan agroforestry system

Science.gov (United States)

Agroforestry systems have widely been recognized for their potential to foster long-term carbon sequestration in woody perennials. This study aims to determine the above-ground biomass in a 16-year-old red oak (Quercus rubra) - pecan (Carya illinoinensis) silvopastoral planting (141 and 53 trees ha-...

Elm genetic diversity and hybridization in the presence of Dutch elm disease

Science.gov (United States)

Johanne Brunet; Raymond P. Guries

2017-01-01

The impact of Dutch elm disease (DED) on the genetic diversity of slippery elm (Ulmus rubra) is summarized and its potential impact on the genetic diversity of other North American native elms, American elm (U. americana), rock elm (U. thomasii), winged elm (U. alata), cedar elm (

Phylloplane bacteria increase the negative impact of food limitation on insect fitness

NARCIS (Netherlands)

Olson, Grant L.; Myers, Judith H.; Hemerik, Lia; Cory, Jenny S.

2017-01-01

1. When populations of herbivorous insects increase in density, they can alter the quantity or quality of their food. The impacts of diet-related stressors on insect fitness have been investigated singly, but not simultaneously. 2. Foliage quantity and quality of red alder, Alnus rubra, were

Impact of soil nematodes on salt-marsh plants : a pilot experiment

NARCIS (Netherlands)

Dormann, CF; van der Wal, R

2001-01-01

We tested whether the removal of nematodes by means of nematicide application changed plant performance or influenced plant competition. The study involved the two common plant species Artemisia maritima and Festuca rubra growing in intact sods collected from a temperate salt marsh. Half of the sods

Neighborhood effects and genetic structure in a clonal grass: The role of the spatial structure of the environment

Czech Academy of Sciences Publication Activity Database

Herben, Tomáš; Hara, T.; Hadincová, Věroslava; Krahulec, František; Pecháčková, Sylvie; Skálová, Hana; Suzuki, J. I.

2001-01-01

Roč. 16, - (2001), s. 1-11 ISSN 0913-557x R&D Projects: GA ČR GA206/98/1533; GA ČR GA206/99/0889 Institutional research plan: CEZ:AV0Z6005908 Keywords : environmental heterogeneity * Festuca rubra * plasticity Subject RIV: EF - Botanics

Managing succession in conifer plantations: converting young red pine (Pinus resinosa Ait.) plantations to native forest types by thinning and underplantiing

Science.gov (United States)

William C. Parker; Ken A. Elliott; Daniel C. Dey; Eric Boysen; Steven G. Newmaster

2001-01-01

The effects of thinning on growth and survival of white pine (Pinus strobus L.), white ash (Fraxinus americana L.), and red oak (Quercus rubra L.), and understory plant diversity were examined in a young red pine (Pinus resinosa Ait.) plantation. Five years after thinning, seedling diameter,...

Small-scale shifting mosaics of two dominant grassland species: the possible role of soil-borne pathogens

NARCIS (Netherlands)

Olff, H.; Hoorens, B.; De Goede, R.G.M.; Van der Putten, W.H.; Gleichman, J.M.

2000-01-01

We analyzed the dynamics of dominant plant species in a grazed grassland over 17 years, and investigated whether local shifts in these dominant species, leading to vegetation mosaics, could be attributed to interactions between plants and soil-borne pathogens. We found that Festuca rubra and Carer

Small-scale shifting mosaics of two dominant grassland species : the possible role of soil-borne pathogens

NARCIS (Netherlands)

Olff, H.; Hoorens, B.; Goede, R.G.M. de; Putten, W.H. van der; Gleichman, J.M.

2000-01-01

We analyzed the dynamics of dominant plant species in a grazed grassland over 17 years, and investigated whether local shifts in these dominant species, leading to vegetation mosaics, could be attributed to interactions between plants and soil-borne pathogens. We found that Festuca rubra and Carex

Do chestnut, northern red, and white oak germinant seedlings respond similary to light treatments? II. Gas exchange and chlorophyll responses

Science.gov (United States)

Joanne Rebbeck; Amy Scherzer; Kurt. Gottschalk

2012-01-01

Understanding differences in physiological and growth strategies in low-light environments among upland oak species may help managers address the challenges of oaks' poor regeneration. Gas exchange and chlorophyll content were measured for northern red oak (Quercus rubra L.), chestnut oak (Quercus prinus L.), and white oak (...

Edge-glued panels from Alaska hardwoods: retail manager perspectives

Science.gov (United States)

David Nicholls; Matthew Bumgardner; Valerie Barber

2010-01-01

In Alaska, red alder (Alnus rubra Bong.) and paper birch (Betula papyrifera Marsh.) are both lesser-known hardwoods grown, harvested, and manufactured into appearance products, with potential for increased utilization. The production of edgeglued panels from red alder and paper birch offers one expansion opportunity for wood...

Case report

African Journals Online (AJOL)

raoul

2010-08-09

Aug 9, 2010 ... sclerodactyly with finger flexion contractures and digital tuft loss (Figure 1). ... such as Vitamin A and its derivatives [30], methotrexate and cyclosporine ... Desquamation from the parts covered with hair. ... Shvili D, David M, Mimouni M. Childhood-onset pityriasis rubra pilaris with immunologic abnormalities.

Environmental Assessment for BRAC Facilities and Remote Field Training Site, Wright-Patterson Air Force Base

Science.gov (United States)

2008-03-01

survey (BHE, 2001). Radio tracking of these two bats confirmed the presence of a maternity colony in a dead slippery elm (Ulmus rubra) in a woodlot...The most common trees observed were black walnut (Juglans nigra), elm (Ulmus spp.), eastern cottonwood, willow, ash (Fraxinus americana), sycamore

Not only the butterflies: managing ants on road verges to benefit Phengaris (Maculinea) butterflies

NARCIS (Netherlands)

Wynhoff, I.; Gestel, van R.; Swaay, van C.; Langevelde, van F.

2011-01-01

Obligate myrmecophilic butterfly species, such as Phengaris (Maculinea) teleius and P. nausithous, have narrow habitat requirements. Living as a caterpillar in the nests of the ant species Myrmica scabrinodis and M. rubra, respectively, they can only survive on sites with both host ants and the host

Seeing with electrons

International Nuclear Information System (INIS)

Nellist, P.

2006-01-01

Commercially available lens correctors are extending the reach of electron microscopes to unprecedented atomic scales, as Peter Nellist describes. The electron microscope was invented in 1933 and is based on the principle that electrons have a wavelength that is inversely proportional to their momentum. There are two basic types: transmission electron microscopes and scanning electron microscopes, plus a hybrid of the two. The lenses in an electron microscope are provided by electromagnetic fields, but they suffer from spherical aberration. The addition of octupole and quadrupole corrector fields has improved the resolution of the electron microscope to better than 0.1 nm in the last decade. The next step is to correct for chromatic aberration, after which the resolution of the microscope will probably be limited by the size of the atom itself. (U.K.)

Introduction to electronics

CERN Multimedia

CERN. Geneva

2005-01-01

Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

Multiple electron generation in a sea of electronic states

Science.gov (United States)

Witzel, Wayne; Shabaev, Andrew; Efros, Alexander; Hellberg, Carl; Verne, Jacobs

2009-03-01

In traditional bulk semiconductor photovoltaics (PVs), each photon may excite a single electron-hole, wasting excess energy beyond the band-gap as heat. In nanocrystals, multiple excitons can be generated from a single photon, enhancing the PV current. Multiple electron generation (MEG) may result from Coulombic interactions of the confined electrons. Previous investigations have been based on incomplete or over-simplified electronic-state representations. We present results of quantum simulations that include hundreds of thousands of configuration states and show how the complex dynamics, even in a closed electronic system, yields a saturated MEG effect on a femtosecond timescale. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Electron collision cross sections and electron swarm parameters for gas molecules

International Nuclear Information System (INIS)

Hayashi, Makoto

1986-01-01

Elastic and inelastic electron collision cross sections for molecules which interest in radiation research have been determined from available electron beam and electron swarm data by utilizing the Boltzmann equation and Monte Carlo simulation method. Electron drift velocity data which interest in radiation Pysics have been discussed and some calculated results of electron drift velocity data for CF 4 and CF 4 -inert gases mixtures will be presented. (author)

Electronic payment systems

OpenAIRE

Mláka, Michal

2010-01-01

This bachelor thesis analysis issue of electronic payment systems. It discusses their use for payments on the internet and sending funds via e-mail. The first part is devoted to the theoretical definition and legislation of the issuance of electronic money and activities of electronic money institutions. The main part of the work clearly focuses on the use of e-wallets, which is an integral part of electronic payment systems. E-wallet of electronic payment system Moneybookers is considered as...

Wigner-like crystallization of Anderson-localized electron systems with low electron densities

CERN Document Server

Slutskin, A A; Pepper, M

2002-01-01

We consider an electron system under conditions of strong Anderson localization, taking into account interelectron long-range Coulomb repulsion. We establish that at sufficiently low electron densities and sufficiently low temperatures the Coulomb electron interaction brings about ordering of the Anderson-localized electrons into a structure that is close to an ideal (Wigner) crystal lattice, provided the dimension of the system is > 1. This Anderson-Wigner glass (AWG) is a new macroscopic electron state that, on the one hand, is beyond the conventional Fermi glass concept, and on the other hand, qualitatively differs from the known 'plain' Wigner glass (inherent in self-localized electron systems) in that the random slight electron displacements from the ideal crystal sites essentially depend on the electron density. With increasing electron density the AWG is found to turn into the plain Wigner glass or Fermi glass, depending on the width of the random spread of the electron levels. It is shown that the res...

Excess electrons in methanol clusters: Beyond the one-electron picture

Science.gov (United States)

Pohl, Gábor; Mones, Letif; Turi, László

2016-10-01

We performed a series of comparative quantum chemical calculations on various size negatively charged methanol clusters, ("separators=" CH 3 OH ) n - . The clusters are examined in their optimized geometries (n = 2-4), and in geometries taken from mixed quantum-classical molecular dynamics simulations at finite temperature (n = 2-128). These latter structures model potential electron binding sites in methanol clusters and in bulk methanol. In particular, we compute the vertical detachment energy (VDE) of an excess electron from increasing size methanol cluster anions using quantum chemical computations at various levels of theory including a one-electron pseudopotential model, several density functional theory (DFT) based methods, MP2 and coupled-cluster CCSD(T) calculations. The results suggest that at least four methanol molecules are needed to bind an excess electron on a hydrogen bonded methanol chain in a dipole bound state. Larger methanol clusters are able to form stronger interactions with an excess electron. The two simulated excess electron binding motifs in methanol clusters, interior and surface states, correlate well with distinct, experimentally found VDE tendencies with size. Interior states in a solvent cavity are stabilized significantly stronger than electron states on cluster surfaces. Although we find that all the examined quantum chemistry methods more or less overestimate the strength of the experimental excess electron stabilization, MP2, LC-BLYP, and BHandHLYP methods with diffuse basis sets provide a significantly better estimate of the VDE than traditional DFT methods (BLYP, B3LYP, X3LYP, PBE0). A comparison to the better performing many electron methods indicates that the examined one-electron pseudopotential can be reasonably used in simulations for systems of larger size.

Electron dose rate and photon contamination in electron arc therapy

International Nuclear Information System (INIS)

Pla, M.; Podgorsak, E.B.; Pla, C.

1989-01-01

The electron dose rate at the depth of dose maximum dmax and the photon contamination are discussed as a function of several parameters of the rotational electron beam. A pseudoarc technique with an angular increment of 10 degrees and a constant number of monitor units per each stationary electron field was used in our experiments. The electron dose rate is defined as the electron dose at a given point in phantom divided by the number of monitor units given for any one stationary electron beam. For a given depth of isocenter di the electron dose rates at dmax are linearly dependent on the nominal field width w, while for a given w the dose rates are inversely proportional to di. The dose rates for rotational electron beams with different di are related through the inverse square law provided that the two beams have (di,w) combinations which give the same characteristic angle beta. The photon dose at the isocenter depends on the arc angle alpha, field width w, and isocenter depth di. For constant w and di the photon dose at isocenter is proportional to alpha, for constant alpha and w it is proportional to di, and for constant alpha and di it is inversely proportional to w. The w and di dependence implies that for the same alpha the photon dose at the isocenter is inversely proportional to the electron dose rate at dmax

Power Electronics

DEFF Research Database (Denmark)

Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

2008-01-01

is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

Electron Emission from Ultra-Large Area MOS Electron Emitters

DEFF Research Database (Denmark)

Thomsen, Lasse Bjørchmar; Nielsen, Gunver; Vendelbo, Søren Bastholm

2009-01-01

Ultralarge metal-oxide-semiconductor (MOS) devices with an active oxide area of 1 cm2 have been fabricated for use as electron emitters. The MOS structures consist of a Si substrate, a SiO2 tunnel barrier (~5 nm), a Ti wetting layer (3–10 Å), and a Au top layer (5–60 nm). Electron emission from...... layer is varied from 3 to 10 Å which changes the emission efficiency by more than one order of magnitude. The apparent mean free path of ~5 eV electrons in Au is found to be 52 Å. Deposition of Cs on the Au film increased the electron emission efficiency to 4.3% at 4 V by lowering the work function....... Electron emission under high pressures (up to 2 bars) of Ar was observed. ©2009 American Vacuum Society...

Comparative analysis of the terms "electronic commerce" and "electronic business"

OpenAIRE

Kavaliauskienė, Virginija; Šarapovas, Tadas

2002-01-01

Establishing the terms that clearly and consistently describe growing and dynamic networked economy is a critical first step toward further analysis and evaluation of electronic commerce and electronic business processes. Electronic commerce is making an impact on the ways that purchasing activities are being conducted. Much of the early literature on this subject was very speculative. However, the growth of e-commerce has enabled more observations to be made of the use of electronic business...

Electron-electron interaction and transfer ionization in fast ion-atom collisions

International Nuclear Information System (INIS)

Voitkiv, A B

2008-01-01

Recently it was pointed out that electron capture occurring in fast ion-atom collisions can proceed via a mechanism which earlier was not considered. In the present paper we study this mechanism in more detail. Similarly as in radiative capture, where the electron transfer occurs due to the interaction with the radiation field and proceeds via emission of a photon, within this mechanism the electron capture is caused by the interaction with another atomic electron leading mainly to the emission of the latter. In contrast to the electron-electron Thomas capture, this electron-electron (E-E) mechanism is basically a first-order one having similarities to the kinematic and radiative capture channels. It also possesses important differences with the latter two. Leading to transfer ionization, this first-order capture mechanism results in the electron emission mainly in the direction opposite to the motion of the projectile ion. The same, although less pronounced, feature is also characteristic for the momenta of the target recoil ions produced via this mechanism. It is also shown that the action of the E-E mechanism is clearly seen in recent experimental data on the transfer ionization in fast proton-helium collisions.

Determination of electron temperature and electron density in ...

African Journals Online (AJOL)

It is seen that the electron temperature increases from 5.8 × 102 oK to 7.83 × 104 oK as the pd is reduced from 130mm Hg × mm to 60 mm Hg × mm for argon. The electron densities increases from 2.8 × 1011/cm3 to 3.2 × 1011 /cm3 for the same variation of pds. For air the electron temperature increases from 3.6 × 104 oK to ...

Optimising electron microscopy experiment through electron optics simulation

Energy Technology Data Exchange (ETDEWEB)

Kubo, Y. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France); Hitachi High-Technologies Corporation, 882, Ichige, Hitachinaka, Ibaraki 312-8504 (Japan); Gatel, C.; Snoeck, E. [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France); Houdellier, F., E-mail: florent.houdellier@cemes.fr [CEMES-CNRS, 29 Rue Jeanne Marvig, 31055 Toulouse France (France)

2017-04-15

We developed a new type of electron trajectories simulation inside a complete model of a modern transmission electron microscope (TEM). Our model incorporates the precise and real design of each element constituting a TEM, i.e. the field emission (FE) cathode, the extraction optic and acceleration stages of a 300 kV cold field emission gun, the illumination lenses, the objective lens, the intermediate and projection lenses. Full trajectories can be computed using magnetically saturated or non-saturated round lenses, magnetic deflectors and even non-cylindrical symmetry elements like electrostatic biprism. This multi-scale model gathers nanometer size components (FE tip) with parts of meter length (illumination and projection systems). We demonstrate that non-trivial TEM experiments requiring specific and complex optical configurations can be simulated and optimized prior to any experiment using such model. We show that all the currents set in all optical elements of the simulated column can be implemented in the real column (I2TEM in CEMES) and used as starting alignment for the requested experiment. We argue that the combination of such complete electron trajectory simulations in the whole TEM column with automatic optimization of the microscope parameters for optimal experimental data (images, diffraction, spectra) allows drastically simplifying the implementation of complex experiments in TEM and will facilitate the development of advanced use of the electron microscope in the near future. - Highlights: • Using dedicated electron optics software, we calculate full electrons trajectories inside a modern transmission electron microscope. • We have determined how to deal with multi-scale electron optics elements like high voltage cold field emission source. • W • e have succeed to model both weak and strong magnetic lenses whether in saturated or unsaturated conditions as well as electrostatic biprism and magnetic deflectors. • We have applied this model

Optimising electron microscopy experiment through electron optics simulation

International Nuclear Information System (INIS)

Kubo, Y.; Gatel, C.; Snoeck, E.; Houdellier, F.

2017-01-01

We developed a new type of electron trajectories simulation inside a complete model of a modern transmission electron microscope (TEM). Our model incorporates the precise and real design of each element constituting a TEM, i.e. the field emission (FE) cathode, the extraction optic and acceleration stages of a 300 kV cold field emission gun, the illumination lenses, the objective lens, the intermediate and projection lenses. Full trajectories can be computed using magnetically saturated or non-saturated round lenses, magnetic deflectors and even non-cylindrical symmetry elements like electrostatic biprism. This multi-scale model gathers nanometer size components (FE tip) with parts of meter length (illumination and projection systems). We demonstrate that non-trivial TEM experiments requiring specific and complex optical configurations can be simulated and optimized prior to any experiment using such model. We show that all the currents set in all optical elements of the simulated column can be implemented in the real column (I2TEM in CEMES) and used as starting alignment for the requested experiment. We argue that the combination of such complete electron trajectory simulations in the whole TEM column with automatic optimization of the microscope parameters for optimal experimental data (images, diffraction, spectra) allows drastically simplifying the implementation of complex experiments in TEM and will facilitate the development of advanced use of the electron microscope in the near future. - Highlights: • Using dedicated electron optics software, we calculate full electrons trajectories inside a modern transmission electron microscope. • We have determined how to deal with multi-scale electron optics elements like high voltage cold field emission source. • W • e have succeed to model both weak and strong magnetic lenses whether in saturated or unsaturated conditions as well as electrostatic biprism and magnetic deflectors. • We have applied this model

Lead-Free Electronics: Impact for Space Electronics

Science.gov (United States)

Sampson, Michael J.

2010-01-01

Pb is used as a constituent in solder alloys used to connect and attach electronic parts to printed wiring boards (PWBs). Similar Pbbearing alloys are electroplated or hot dipped onto the terminations of electronic parts to protect the terminations and make them solderable. Changing to Pb-free solders and termination finishes has introduced significant technical challenges into the supply chain. Tin/lead (Sn/Pb) alloys have been the solders of choice for electronics for more than 50 years. Pb-free solder alloys are available but there is not a plug-in replacement for 60/40 or 63/37 (Sn/Pb) alloys, which have been the industry workhorses.

Observation of electron plasma waves in plasma of two-temperature electrons

International Nuclear Information System (INIS)

Ikezawa, Shunjiro; Nakamura, Yoshiharu.

1981-01-01

Propagation of electron plasma waves in a large and unmagnetized plasma containing two Maxwellian distributions of electrons is studied experimentally. Two kinds of plasma sources which supply electrons of different temperature are used. The temperature ratio is about 3 and the density ratio of hot to cool electrons is varied from 0 to 0.5. A small contamination of hot electrons enhances the Landau damping of the principal mode known as the Bohm-Gross mode. When the density of hot electrons is larger than about 0.2, two modes are observed. The results agree with theoretical dispersion relations when excitation efficiencies of the modes are considered. (author)

Electron energy and electron trajectories in an inverse free-electron laser accelerator based on a novel electrostatic wiggler

Science.gov (United States)

Nikrah, M.; Jafari, S.

2016-06-01

We expand here a theory of a high-gradient laser-excited electron accelerator based on an inverse free-electron laser (inverse-FEL), but with innovations in the structure and design. The electrostatic wiggler used in our scheme, namely termed the Paul wiggler, is generated by segmented cylindrical electrodes with applied oscillatory voltages {{V}\\text{osc}}(t) over {{90}\\circ} segments. The inverse-FEL interaction can be described by the equations that govern the electron motion in the combined fields of both the laser pulse and Paul wiggler field. A numerical study of electron energy and electron trajectories has been made using the fourth-order Runge-Kutta method. The results indicate that the electron attains a considerable energy at short distances in this device. It is found that if the electron has got sufficient suitable wiggler amplitude intensities, it can not only gain higher energy in longer distances, but also can retain it even after the passing of the laser pulse. In addition, the results reveal that the electron energy gains different peaks for different initial axial velocities, so that a suitable small initial axial velocity of e-beam produces substantially high energy gain. With regard to the transverse confinement of the electron beam in a Paul wiggler, there is no applied axial guide magnetic field in this device.

Plasmaspheric electron content

International Nuclear Information System (INIS)

Hartmann, G.K.

1978-01-01

Measurements of the plasmaspheric electron content are reviewed with particular reference to the ATS-6 radio beacon experiment. From the review, it appears likely that measurement of the plasmaspheric electron content is the only one capable of monitoring electron fluxes continuously between L 1 and L 2. Some recent important results deduced from plasmaspheric electron content measurements are discussed

A 20 keV electron gun system for the electron irradiation experiments

International Nuclear Information System (INIS)

Mahapatra, S.K.; Dhole, S.D.; Bhoraskar, V.N.

2005-01-01

An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 μA. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure ∼10 -7 mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours

A 20 keV electron gun system for the electron irradiation experiments

Energy Technology Data Exchange (ETDEWEB)

Mahapatra, S.K. [Department of Physics, University of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, University of Pune, Pune 411007 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411007 (India)]. E-mail: vnb@physics.unipune.ernet.in

2005-01-01

An electron gun consisting of cathode, focusing electrode, control electrode and anode has been designed and fabricated for the electron irradiation experiments. This electron gun can provide electrons of any energy over the range 1-20 keV, with current upto 50 {mu}A. This electron gun and a Faraday cup are mounted in the cylindrical chamber. The samples are fixed on the Faraday cup and irradiated with electrons at a pressure {approx}10{sup -7} mbar. The special features of this electron gun system are that, at any electron energy above 1 keV, the electron beam diameter can be varied from 5 to 120 mm on the Faraday cup mounted at a distance of 200 mm from the anode in the chamber. The variation in the electron current over the beam spot of 120 mm diameter is less than 15% and the beam current stability is better than 5%. This system is being used for studying the irradiation effects of 1-20 keV energy electrons on the space quality materials in which the irradiation time may vary from a few tens of seconds to hours.

Effect of electron beam on the properties of electron-acoustic rogue waves

Science.gov (United States)

El-Shewy, E. K.; Elwakil, S. A.; El-Hanbaly, A. M.; Kassem, A. I.

2015-04-01

The properties of nonlinear electron-acoustic rogue waves have been investigated in an unmagnetized collisionless four-component plasma system consisting of a cold electron fluid, Maxwellian hot electrons, an electron beam and stationary ions. It is found that the basic set of fluid equations is reduced to a nonlinear Schrodinger equation. The dependence of rogue wave profiles and the associated electric field on the carrier wave number, normalized density of hot electron and electron beam, relative cold electron temperature and relative beam temperature are discussed. The results of the present investigation may be applicable in auroral zone plasma.

Electron cooling and recombination experiments with an adiabatically expanded electron beam

International Nuclear Information System (INIS)

Pastuszka, S.; Heidelberg Univ.; Schramm, U.; Heidelberg Univ.; Grieser, M.; Heidelberg Univ.; Broude, C.; Heidelberg Univ.; Grimm, R.; Heidelberg Univ.; Habs, D.; Heidelberg Univ.; Kenntner, J.; Heidelberg Univ.; Miesner, H.J.; Heidelberg Univ.; Schuessler, T.; Heidelberg Univ.; Schwalm, D.; Heidelberg Univ.; Wolf, A.; Heidelberg Univ.

1996-01-01

Magnetically guided electron beams with transverse temperatures reduced with respect to the cathode temperature by a factor of more than 7 were realized in the electron cooling device of the heavy-ion storage ring TSR and the effect of the reduced transverse temperature in recombination and electron cooling experiments was studied. Measured dielectronic recombination resonances at low relative energy and spectra of laser-stimulated recombination indicate that transverse electron temperatures of about 17 meV have been obtained at cathode temperatures of about 110 meV. The temperature dependence of the spontaneous electron-ion recombination rate during electron cooling was investigated and found to follow the inverse square-root law expected from the theory of radiative recombination, although the measured absolute rates are higher than predicted. A new method based on analyzing the intensity of the fluorescence light emitted during simultaneous laser and electron cooling is used to measure the longitudinal electron cooling force in a range of relative velocities extending over two orders of magnitude (10 5 -10 7 cm/s). The results confirm the occurrence of 'magnetized electron cooling' also at the reduced transverse temperature and show that, compared to earlier measurements at the high transverse temperature, the cooling force increases by about a factor of 2; a considerably larger increase by a factor of ∼5 would be expected if 'magnetized electron cooling' would not exist. (orig.)

Electronic structure of elements and compounds and electronic phases of solids

International Nuclear Information System (INIS)

Nadykto, B.A.

2000-01-01

The paper reviews technique and computed energies for various electronic states of many-electron multiply charged ions, molecular ions, and electronic phases of solids. The model used allows computation of the state energy for free many-electron multiply charged ions with relative accuracy ∼10 -4 suitable for analysis of spectroscopy data

Three-dimensional nanofabrication by electron-beam-induced deposition using 200-keV electrons in scanning transmission electron microscope

International Nuclear Information System (INIS)

Liu, Z.Q.; Mitsuishi, K.; Furuya, K.

2005-01-01

Attempts were made to fabricate three-dimensional nanostructures on and out of a substrate by electron-beam-induced deposition in a 200-kV scanning transmission electron microscope. Structures with parallel wires over the substrate surface were difficult to fabricate due to the direct deposition of wires on both top and bottom surfaces of the substrate. Within the penetration depth of the incident electron beam, nanotweezers were fabricated by moving the electron beam beyond different substrate layers. Combining the deposition of self-supporting wires and self-standing tips, complicated three-dimensional doll-like, flag-like, and gate-like nanostructures that extend out of the substrate were successfully fabricated with one-step or multi-step scans of the electron beam. Effects of coarsening, nucleation, and distortion during electron-beam-induced deposition are discussed. (orig.)

Secondary electron emission yield in the limit of low electron energy

CERN Document Server

Andronov, A.N.; Kaganovich, I.D.; Startsev, E.A.; Raitses, Y.; Demidov, V.I.

2013-04-22

Secondary electron emission (SEE) from solids plays an important role in many areas of science and technology.1 In recent years, there has been renewed interest in the experimental and theoretical studies of SEE. A recent study proposed that the reflectivity of very low energy electrons from solid surface approaches unity in the limit of zero electron energy2,3,4, If this was indeed the case, this effect would have profound implications on the formation of electron clouds in particle accelerators,2-4 plasma measurements with electrostatic Langmuir probes, and operation of Hall plasma thrusters for spacecraft propulsion5,6. It appears that, the proposed high electron reflectivity at low electron energies contradicts to numerous previous experimental studies of the secondary electron emission7. The goal of this note is to discuss possible causes of these contradictions.

Electron spectroscopy

International Nuclear Information System (INIS)

Hegde, M.S.

1979-01-01

An introduction to the various techniques in electron spectroscopy is presented. These techniques include: (1) UV Photoelectron spectroscopy, (2) X-ray Photoelectron spectroscopy, (3) Auger electron spectroscopy, (4) Electron energy loss spectroscopy, (5) Penning ionization spectroscopy and (6) Ion neutralization spectroscopy. The radiations used in each technique, the basis of the technique and the special information obtained in structure determination in atoms and molecules by each technique are summarised. (A.K.)

Response of northern red oak, black walnut, and white ash seedlings to various levels of simulated summer deer browsing

Science.gov (United States)

Robert C. Morrissey; Douglass F. Jacobs; John R. Seifert

2008-01-01

Understanding the response of tree seedlings to browsing by white-tailed deer (Odocoileus virginianus Zimmerman) is critical to the management of high value hardwood plantations in the Central Hardwood Forest Region. One-year-old black walnut (Juglans nigra L.), northern red oak (Quercus rubra L.), and white ash...

Temporal development of vegetation and geomorphology in a man-made beach-dune system by natural processes

DEFF Research Database (Denmark)

Vestergaard, Peter

2006-01-01

with F. rubra and the invasive alien Rosa rugosa. It was concluded, that the main trends in the geomorphological and vegetational development of the man-made beach-dune system is similar to the development in natural dunes. In the future, further accretion and seaward dune formation may be expected...

Development of northern red oak rooted cutting and enrichment planting systems

Science.gov (United States)

Matthew H. Gocke; Jamie Schuler; Daniel J. Robison; Barry Goldfarb

2005-01-01

Enrichment planting may provide an efficient means to establish elite northern red oak (Quercus rubra L.) genotypes in recently harvested natural forests. However, planting northern red oak (NRO) seedlings into natural stands has proven difficult in the past, especially when competition and other stress factors are not controlled.

Responses of northern red oak seedlings to lime and deer exclosure fencing in Pennsylvania

Science.gov (United States)

Robert P. Long; Patrick H. Brose; Stephen B. Horsley

2012-01-01

In Pennsylvania, two hypotheses compete to explain the chronic oak (Quercus spp.) regeneration problem: excessive deer browsing and soil cation depletion. We tested these hypotheses by evaluating the effect of forest liming and deer exclosure fencing on northern red oak (Quercus rubra L.) seedling growth and nutrition in five...

Polycythemia Vera

Science.gov (United States)

... Polycythemia Vera Also known as What Is Polycythemia vera (POL-e-si-THEE-me-ah VAY-rah or VE- ... MY-e-lo-PATH-ik) polycythemia Myeloproliferative (MY-e-lo-pro-LIF-er-ah-tiv) disorder Osler disease Polycythemia rubra vera Polycythemia with chronic cyanosis (SI-ah-NO-sis) ...

Environmental Assessment for Physical Fitness Center Tinker Air Force Base, Oklahoma

Science.gov (United States)

2010-04-01

Tinker AFB contains such species as American elm (Ulmus Americana), slippery elm (Ulmus rubra), hackberry (Celtis spp.), and cottonwood (Poplus...The other two major drainages on the Base are Elm Creek and Hog Creek, both of which flow south off Base and join the Little River. The on-Base

Elevated CO2 compensates for water stress in northern red oak

Science.gov (United States)

Patricia T. Tomlinson; Paul D. Anderson

1996-01-01

Global climate change models predict decreased rainfall in association with elevated CO2 in the western Lakes States region. Currently, the western edge of northern red oak (Quercus rubra L.) distribution coincides with the most xeric conditions of its ecological range. Decreased rainfall and water availability could alter...

杨梅叶水溶性提取物的抗氧化、抗菌活性 与防腐应用

Czech Academy of Sciences Publication Activity Database

Jun, Y.; Li-yun, Z.; Jun-qing, W.; Jie, Y.; Langhansová, Lenka; Vaněk, Tomáš; Yong-sheng, G.; Ji-dong, L.

-, č. 2 (2014), s. 198-202 ISSN 1006-2513 R&D Projects: GA MŠk LH12165 Institutional support: RVO:61389030 Keywords : Myrica rubra leaf * antioxidation * antimicrobial Subject RIV: FR - Pharmacology ; Medidal Chemistry http://caod.oriprobe.com/articles/42399762/Antioxidant_antimicrobial_and_antisepsis_properties_of_the_water_solub.htm