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Sample records for broadly conserved crustacean

  1. Environmental sex determination in the branchiopod crustacean Daphnia magna: deep conservation of a Doublesex gene in the sex-determining pathway.

    Directory of Open Access Journals (Sweden)

    Yasuhiko Kato

    2011-03-01

    Full Text Available Sex-determining mechanisms are diverse among animal lineages and can be broadly divided into two major categories: genetic and environmental. In contrast to genetic sex determination (GSD, little is known about the molecular mechanisms underlying environmental sex determination (ESD. The Doublesex (Dsx genes play an important role in controlling sexual dimorphism in genetic sex-determining organisms such as nematodes, insects, and vertebrates. Here we report the identification of two Dsx genes from Daphnia magna, a freshwater branchiopod crustacean that parthenogenetically produces males in response to environmental cues. One of these genes, designated DapmaDsx1, is responsible for the male trait development when expressed during environmental sex determination. The domain organization of DapmaDsx1 was similar to that of Dsx from insects, which are thought to be the sister group of branchiopod crustaceans. Intriguingly, the molecular basis for sexually dimorphic expression of DapmaDsx1 is different from that of insects. Rather than being regulated sex-specifically at the level of pre-mRNA splicing in the coding region, DapmaDsx1 exhibits sexually dimorphic differences in the abundance of its transcripts. During embryogenesis, expression of DapmaDsx1 was increased only in males and its transcripts were primarily detected in male-specific structures. Knock-down of DapmaDsx1 in male embryos resulted in the production of female traits including ovarian maturation, whereas ectopic expression of DapmaDsx1 in female embryos resulted in the development of male-like phenotypes. Expression patterns of another D. magna Dsx gene, DapmaDsx2, were similar to those of DapmaDsx1, but silencing and overexpression of this gene did not induce any clear phenotypic changes. These results establish DapmaDsx1 as a key regulator of the male phenotype. Our findings reveal how ESD is implemented by selective expression of a fundamental genetic component that is

  2. Sequence Conservation and Sexually Dimorphic Expression of the Ftz-F1 Gene in the Crustacean Daphnia magna

    OpenAIRE

    Nur Syafiqah Mohamad Ishak; Yasuhiko Kato; Tomoaki Matsuura; Hajime Watanabe

    2016-01-01

    Identifying the genes required for environmental sex determination is important for understanding the evolution of diverse sex determination mechanisms in animals. Orthologs of Drosophila orphan receptor Fushi tarazu factor-1 (Ftz-F1) are known to function in genetic sex determination. In contrast, their roles in environmental sex determination remain unknown. In this study, we have cloned and characterized the Ftz-F1 ortholog in the branchiopod crustacean Daphnia magna, which produces males ...

  3. Sequence Conservation and Sexually Dimorphic Expression of the Ftz-F1 Gene in the Crustacean Daphnia magna.

    Directory of Open Access Journals (Sweden)

    Nur Syafiqah Mohamad Ishak

    Full Text Available Identifying the genes required for environmental sex determination is important for understanding the evolution of diverse sex determination mechanisms in animals. Orthologs of Drosophila orphan receptor Fushi tarazu factor-1 (Ftz-F1 are known to function in genetic sex determination. In contrast, their roles in environmental sex determination remain unknown. In this study, we have cloned and characterized the Ftz-F1 ortholog in the branchiopod crustacean Daphnia magna, which produces males in response to environmental stimuli. Similar to that observed in Drosophila, D. magna Ftz-F1 (DapmaFtz-F1 produces two splicing variants, αFtz-F1 and βFtz-F1, which encode 699 and 777 amino acids, respectively. Both isoforms share a DNA-binding domain, a ligand-binding domain, and an AF-2 activation domain and differ only at the A/B domain. The phylogenetic position and genomic structure of DapmaFtz-F1 suggested that this gene has diverged from an ancestral gene common to branchiopod crustacean and insect Ftz-F1 genes. qRT-PCR showed that at the one cell and gastrulation stages, both DapmaFtz-F1 isoforms are two-fold more abundant in males than in females. In addition, in later stages, their sexual dimorphic expressions were maintained in spite of reduced expression. Time-lapse imaging of DapmaFtz-F1 RNAi embryos was performed in H2B-GFP expressing transgenic Daphnia, demonstrating that development of the RNAi embryos slowed down after the gastrulation stage and stopped at 30-48 h after ovulation. DapmaFtz-F1 shows high homology to insect Ftz-F1 orthologs based on its amino acid sequence and exon-intron organization. The sexually dimorphic expression of DapmaFtz-F1 suggests that it plays a role in environmental sex determination of D. magna.

  4. Sequence Conservation and Sexually Dimorphic Expression of the Ftz-F1 Gene in the Crustacean Daphnia magna

    Science.gov (United States)

    Mohamad Ishak, Nur Syafiqah; Kato, Yasuhiko; Matsuura, Tomoaki; Watanabe, Hajime

    2016-01-01

    Identifying the genes required for environmental sex determination is important for understanding the evolution of diverse sex determination mechanisms in animals. Orthologs of Drosophila orphan receptor Fushi tarazu factor-1 (Ftz-F1) are known to function in genetic sex determination. In contrast, their roles in environmental sex determination remain unknown. In this study, we have cloned and characterized the Ftz-F1 ortholog in the branchiopod crustacean Daphnia magna, which produces males in response to environmental stimuli. Similar to that observed in Drosophila, D. magna Ftz-F1 (DapmaFtz-F1) produces two splicing variants, αFtz-F1 and βFtz-F1, which encode 699 and 777 amino acids, respectively. Both isoforms share a DNA-binding domain, a ligand-binding domain, and an AF-2 activation domain and differ only at the A/B domain. The phylogenetic position and genomic structure of DapmaFtz-F1 suggested that this gene has diverged from an ancestral gene common to branchiopod crustacean and insect Ftz-F1 genes. qRT-PCR showed that at the one cell and gastrulation stages, both DapmaFtz-F1 isoforms are two-fold more abundant in males than in females. In addition, in later stages, their sexual dimorphic expressions were maintained in spite of reduced expression. Time-lapse imaging of DapmaFtz-F1 RNAi embryos was performed in H2B-GFP expressing transgenic Daphnia, demonstrating that development of the RNAi embryos slowed down after the gastrulation stage and stopped at 30–48 h after ovulation. DapmaFtz-F1 shows high homology to insect Ftz-F1 orthologs based on its amino acid sequence and exon-intron organization. The sexually dimorphic expression of DapmaFtz-F1 suggests that it plays a role in environmental sex determination of D. magna. PMID:27138373

  5. How a low tissue O2 strategy could be conserved in early crustaceans: the example of the podocopid ostracods.

    Science.gov (United States)

    Corbari, Laure; Carbonel, Pierre; Massabuau, Jean-Charles

    2004-12-01

    An adaptation strategy whereby O(2) partial pressure, P(O(2)), in the tissues is maintained within a low, narrow range of 1-3 kPa, largely independent of the inspired P(O(2)), has been reported in water- and air-breathing poikilotherms and in homeotherms. Based on the postulate that this basic cellular mechanism has been established since the early stages of evolution, it has been hypothesized that it could be the consequence of an early adaptation strategy to maintain cellular oxygenation within the same low and primitive range. To test this hypothesis we studied the basic mechanisms of oxygen regulation in podocopid ostracods, minute crustaceans that have existed on earth for at least 500 million years. Podocopids lack any regulatory mechanism for adapting their ventilation to cope with changes in water oxygenation, and instead adjust their tissue oxygenation status by migrating through the O(2) gradient to sediment layers where the P(O(2)) of the water is 3-5 kPa. Experimental manipulation of the O(2) profile induced their vertical migration to follow this precise water P(O(2)) and demonstrates the existence of a regulation strategy. This strategy must be associated with the lower P(O(2)) values within the animal's carapace valves, showing that podocopids can actively regulate their tissue P(O(2)) at constant but even lower values than the water. In conclusion, the low tissue P(O(2)) strategy could have existed in early crustaceans and, by extension, in early animals. PMID:15557027

  6. Antimicrobial peptides in crustaceans

    OpenAIRE

    RD Rosa; MA Barracco

    2010-01-01

    Crustaceans are a large and diverse invertebrate animal group that mounts a complex and efficient innate immune response against a variety of microorganisms. The crustacean immune system is primarily related to cellular responses and the production and release of important immune effectors into the hemolymph. Antimicrobial proteins and/or peptides (AMPs) are key components of innate immunity and are widespread in nature, from bacteria to vertebrate animals. In crustaceans, 15 distinct AMP fam...

  7. Identification of protective and broadly conserved vaccine antigens from the genome of extraintestinal pathogenic Escherichia coli.

    Science.gov (United States)

    Moriel, Danilo Gomes; Bertoldi, Isabella; Spagnuolo, Angela; Marchi, Sara; Rosini, Roberto; Nesta, Barbara; Pastorello, Ilaria; Corea, Vanja A Mariani; Torricelli, Giulia; Cartocci, Elena; Savino, Silvana; Scarselli, Maria; Dobrindt, Ulrich; Hacker, Jörg; Tettelin, Hervé; Tallon, Luke J; Sullivan, Steven; Wieler, Lothar H; Ewers, Christa; Pickard, Derek; Dougan, Gordon; Fontana, Maria Rita; Rappuoli, Rino; Pizza, Mariagrazia; Serino, Laura

    2010-05-18

    Extraintestinal pathogenic Escherichia coli (ExPEC) are a common cause of disease in both mammals and birds. A vaccine to prevent such infections would be desirable given the increasing antibiotic resistance of these bacteria. We have determined the genome sequence of ExPEC IHE3034 (ST95) isolated from a case of neonatal meningitis and compared this to available genome sequences of other ExPEC strains and a few nonpathogenic E. coli. We found 19 genomic islands present in the genome of IHE3034, which are absent in the nonpathogenic E. coli isolates. By using subtractive reverse vaccinology we identified 230 antigens present in ExPEC but absent (or present with low similarity) in nonpathogenic strains. Nine antigens were protective in a mouse challenge model. Some of them were also present in other pathogenic non-ExPEC strains, suggesting that a broadly protective E. coli vaccine may be possible. The gene encoding the most protective antigen was detected in most of the E. coli isolates, highly conserved in sequence and found to be exported by a type II secretion system which seems to be nonfunctional in nonpathogenic strains. PMID:20439758

  8. Antimicrobial peptides in crustaceans

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    RD Rosa

    2010-11-01

    Full Text Available Crustaceans are a large and diverse invertebrate animal group that mounts a complex and efficient innate immune response against a variety of microorganisms. The crustacean immune system is primarily related to cellular responses and the production and release of important immune effectors into the hemolymph. Antimicrobial proteins and/or peptides (AMPs are key components of innate immunity and are widespread in nature, from bacteria to vertebrate animals. In crustaceans, 15 distinct AMP families are currently recognized, although the great majority (14 families comes from members of the order Decapoda. Crustacean AMPs are generally cationic, gene-encoded molecules that are mainly produced by circulating immune-competent cells (hemocytes or are derived from unrelated proteins primarily involved in other biological functions. In this review, we tentatively classified the crustacean AMPs into four main groups based on their amino acid composition, structural features and multi-functionality. We also attempted to summarize the current knowledge on their implication both in an efficient response to microbial infections and in crustacean survival.

  9. Source size conserving broad band monochromators of fixed exit geometry for high energy synchrotron radiation

    International Nuclear Information System (INIS)

    The degradation of the effective source size by energy tunable, fixed exit, broad band monochromators for high energy synchrotron radiation (40-100 keV) is measured to be below 2 μrad. Two monochromator schemes consisting of either two bent Laue crystals or two SiGe gradient crystals in a non-dispersive setting are characterized. The relative energy bandwidth is about 0.1% and reflectivities are above 80%. The source size broadening and band widths are found to be in agreement with predictions by a kinematical model

  10. Current models broadly neglect specific needs of biodiversity conservation in protected areas under climate change

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    Moloney Kirk A

    2011-05-01

    Full Text Available Abstract Background Protected areas are the most common and important instrument for the conservation of biological diversity and are called for under the United Nations' Convention on Biological Diversity. Growing human population densities, intensified land-use, invasive species and increasing habitat fragmentation threaten ecosystems worldwide and protected areas are often the only refuge for endangered species. Climate change is posing an additional threat that may also impact ecosystems currently under protection. Therefore, it is of crucial importance to include the potential impact of climate change when designing future nature conservation strategies and implementing protected area management. This approach would go beyond reactive crisis management and, by necessity, would include anticipatory risk assessments. One avenue for doing so is being provided by simulation models that take advantage of the increase in computing capacity and performance that has occurred over the last two decades. Here we review the literature to determine the state-of-the-art in modeling terrestrial protected areas under climate change, with the aim of evaluating and detecting trends and gaps in the current approaches being employed, as well as to provide a useful overview and guidelines for future research. Results Most studies apply statistical, bioclimatic envelope models and focus primarily on plant species as compared to other taxa. Very few studies utilize a mechanistic, process-based approach and none examine biotic interactions like predation and competition. Important factors like land-use, habitat fragmentation, invasion and dispersal are rarely incorporated, restricting the informative value of the resulting predictions considerably. Conclusion The general impression that emerges is that biodiversity conservation in protected areas could benefit from the application of modern modeling approaches to a greater extent than is currently reflected in the

  11. Hox genes and study of Hox genes in crustacean

    Institute of Scientific and Technical Information of China (English)

    HOU Lin; CHEN Zhijuan; XU Mingyu; LIN Shengguo; WANG Lu

    2004-01-01

    Homeobox genes have been discovered in many species. These genes are known to play a major role in specifying regional identity along the anterior-posterior axis of animals from a wide range of phyla.The products of the homeotic genes are a set of evolutionarily conserved transcription factors that control elaborate developmental processes and specify cell fates in metazoans. Crustacean, presenting a variety of body plans not encountered in any other class or phylum of the Metazoa, has been shown to possess a single set of homologous Hox genes like insect. The ancestral crustacean Hox gene complex comprised ten genes: eight homologous to the hometic Hox genes and two related to nonhomeotic genes presented within the insect Hox complexes. The crustacean in particular exhibits an abundant diversity segment specialization and tagmosis. This morphological diversity relates to the Hox genes. In crustacean body plan, different Hox genes control different segments and tagmosis.

  12. Identification of broadly conserved cross-species protective Leishmania antigen and its responding CD4+ T cells.

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    Mou, Zhirong; Li, Jintao; Boussoffara, Thouraya; Kishi, Hiroyuki; Hamana, Hiroshi; Ezzati, Peyman; Hu, Chuanmin; Yi, Weijing; Liu, Dong; Khadem, Forough; Okwor, Ifeoma; Jia, Ping; Shitaoka, Kiyomi; Wang, Shufeng; Ndao, Momar; Petersen, Christine; Chen, Jianping; Rafati, Sima; Louzir, Hechmi; Muraguchi, Atsushi; Wilkins, John A; Uzonna, Jude E

    2015-10-21

    There is currently no clinically effective vaccine against leishmaniasis because of poor understanding of the antigens that elicit dominant T cell immunity. Using proteomics and cellular immunology, we identified a dominant naturally processed peptide (PEPCK335-351) derived from Leishmania glycosomal phosphoenolpyruvate carboxykinase (PEPCK). PEPCK was conserved in all pathogenic Leishmania, expressed in glycosomes of promastigotes and amastigotes, and elicited strong CD4(+) T cell responses in infected mice and humans. I-A(b)-PEPCK335-351 tetramer identified protective Leishmania-specific CD4(+) T cells at a clonal level, which comprised ~20% of all Leishmania-reactive CD4(+) T cells at the peak of infection. PEPCK335-351-specific CD4(+) T cells were oligoclonal in their T cell receptor usage, produced polyfunctional cytokines (interleukin-2, interferon-γ, and tumor necrosis factor), and underwent expansion, effector activities, contraction, and stable maintenance after lesion resolution. Vaccination with PEPCK peptide, DNA expressing full-length PEPCK, or rPEPCK induced strong durable cross-species protection in both resistant and susceptible mice. The effectiveness and durability of protection in vaccinated mice support the development of a broadly cross-species protective vaccine against different forms of leishmaniasis by targeting PEPCK. PMID:26491077

  13. Ionotropic crustacean olfactory receptors.

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    Elizabeth A Corey

    Full Text Available The nature of the olfactory receptor in crustaceans, a major group of arthropods, has remained elusive. We report that spiny lobsters, Panulirus argus, express ionotropic receptors (IRs, the insect chemosensory variants of ionotropic glutamate receptors. Unlike insects IRs, which are expressed in a specific subset of olfactory cells, two lobster IR subunits are expressed in most, if not all, lobster olfactory receptor neurons (ORNs, as confirmed by antibody labeling and in situ hybridization. Ligand-specific ORN responses visualized by calcium imaging are consistent with a restricted expression pattern found for other potential subunits, suggesting that cell-specific expression of uncommon IR subunits determines the ligand sensitivity of individual cells. IRs are the only type of olfactory receptor that we have detected in spiny lobster olfactory tissue, suggesting that they likely mediate olfactory signaling. Given long-standing evidence for G protein-mediated signaling in activation of lobster ORNs, this finding raises the interesting specter that IRs act in concert with second messenger-mediated signaling.

  14. IDENTIFICATION OF NICOTINAMIDE MONONUCLEOTIDE DEAMIDASE OF THE BACTERIAL PYRIDINE NUCLEOTIDE CYCLE REVEALS A NOVEL BROADLY CONSERVED AMIDOHYDROLASE FAMILY

    Energy Technology Data Exchange (ETDEWEB)

    Galeazzi, Luca; Bocci, Paolo; Amici, Adolfo; Brunetti, Lucia; Ruggieri, Silverio; Romine, Margaret F.; Reed, Samantha B.; Osterman, Andrei; Rodionov, Dmitry A.; Sorci, Leonardo; Raffaelli, Nadia

    2011-09-27

    The pyridine nucleotide cycle (PNC) is a network of salvage and recycling routes maintaining homeostasis of NAD(P) cofactor pool in the cell. Nicotinamide mononucleotide (NMN) deamidase (EC 3.5.1.42), one of the key enzymes of the bacterial PNC was originally described in Enterobacteria, but the corresponding gene eluded identification for over 30 years. A genomics-based reconstruction of NAD metabolism across hundreds bacterial species suggested that NMN deamidase reaction is the only possible way of nicotinamide salvage in the marine bacterium Shewanella oneidensis. This prediction was verified via purification of native NMN deamidase from S. oneidensis followed by the identification of the respective gene, termed pncC. Enzymatic characterization of the PncC protein, as well as phenotype analysis of deletion mutants, confirmed its proposed biochemical and physiological function in S. oneidensis. Of the three PncC homologs present in E. coli, NMN deamidase activity was confirmed only for the recombinant purified product of the ygaD gene. A comparative analysis at the level of sequence and three dimensional structure, which is available for one of the PncC family member, shows no homology with any previously described amidohydrolases. Multiple alignment analysis of functional and non functional PncC homologs, together with NMN docking experiments, allowed us to tentatively identify the active site area and conserved residues therein. An observed broad phylogenomic distribution of predicted functional PncCs in bacterial kingdom is consistent with a possible role in detoxification of NMN, resulting from NAD utilization by DNA ligase.

  15. Broad-Spectrum Antiviral Activity of Small Interfering RNA Targeting the Conserved RNA Termini of Lassa Virus▿

    OpenAIRE

    Müller, Stefanie; Günther, Stephan

    2007-01-01

    Small interfering RNAs targeting the conserved RNA termini upstream of NP and L gene were found to reduce reporter gene expression from Lassa virus replicon and Lassa virus mRNA expression construct and to inhibit replication of different Lassa virus strains, lymphocytic choriomeningitis virus, and Mopeia virus in cell culture.

  16. Hemolymph proteins in marine crustaceans

    Institute of Scientific and Technical Information of China (English)

    W Sylvester Fredrick; S Ravichandran

    2012-01-01

    This study is done with the aim to bring together the various antimicrobial peptides that are present in the crustacean hemolymph and their sources along with its characteristics. Invertebrates lack immune systems that involve antigen-antibody reactions and do not have an immune memory, therefore most invertebrate species show no evidence of acquired immunity. Crustaceans possess an open circulatory system, where nutrients, oxygen, hormones, and cells are distributed in the hemolymph. They lack adaptive immune system and rely exclusively on their innate immune mechanisms that include both cellular and humoral responses. Antimicrobial peptides and proteins form an important means of host defense in eukaryotes. In addition to their role as endogenous antibiotics, antimicrobial peptides have functions in inflammation, wound repair and regulation of the adaptive immune system. Over the past several years, many antimicrobial peptides have been found and characterized in crabs.

  17. Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins

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    Denong Wang

    2015-03-01

    Full Text Available Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA, for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV, and human cytomegalovirus (HCMV. In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn. These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.

  18. Targeting highly conserved 3'-untranslated region of pecluviruses for sensitive broad-spectrum detection and quantitation by RT-PCR and assessment of phylogenetic relationships.

    Science.gov (United States)

    Dieryck, B; Delfosse, P; Reddy, A S; Bragard, C

    2010-11-01

    The 3'-end region of many virus isolates has been shown to possess conserved sequences in addition to the presence of numerous genomic and subgenomic RNAs. Utilizing these sequences, a broad-spectrum reverse transcription-polymerase chain reaction protocol has been developed to detect all the known Indian peanut clump virus and Peanut clump virus isolates, that cause peanut clump diseases in West Africa and India. The primers were targeted at the highly conserved 3'-untranslated regions of the PCV RNA-1 and RNA-2. The conservation was confirmed by sequencing these untranslated regions of RNA-1 for six isolates and RNA-2 for one isolate. The conserved structure of the RNA-1 and RNA-2 was observed and the importance of this region for the virus survival was confirmed. The primers were also designed for virus quantitation using a Taqman(®)-based real-time RT-PCR. The use of RT-PCR and real-time quantitative RT-PCR improved the sensitivity of PCV detection compared to ELISA. RT-PCR also led to the detection of IPCV and PCV on two new natural hosts: Oldenlandia aspera and Vigna subterranea. Real-time RT-PCR is considered to be an ideal tool for identifying resistant sources to both IPCV and PCV. PMID:20723565

  19. Feeding and Digestion in Larval Decapod Crustaceans

    OpenAIRE

    KUMLU, Metin

    1999-01-01

    This paper reviews the latest findings in larval feeding and digestion of decapod crustacean larvae. The live feeds and manufactured feeds are discussed in relation with the digestive capability of various decapod crustacean larvae. Although some larvae such as penaeid shrimps are successfully cultured on artifical diets, most of lar-val decapod crustaceans are still heavily dependent on live organisms as food (i. e. micro-algae, Arte-mia). Studies with free-living nematodes as an altern...

  20. Decapod crustacean chelipeds: an overview

    Indian Academy of Sciences (India)

    Pitchaimuthu Mariappan; Chellam Balasundaram; Barbara Schmitz

    2000-09-01

    The structure, growth, differentiation and function of crustacean chelipeds are reviewed. In many decapod crustaceans growth of chelae is isometric with allometry level reaching unity till the puberty moult. Afterwards the same trend continues in females, while in males there is a marked spurt in the level of allometry accompanied by a sudden increase in the relative size of chelae. Subsequently they are differentiated morphologically into crusher and cutter making them heterochelous and sexually dimorphic. Of the two, the major chela is used during agonistic encounters while the minor is used for prey capture and grooming. Various biotic and abiotic factors exert a negative effect on cheliped growth. The dimorphic growth pattern of chelae can be adversely affected by factors such as parasitic infection and substrate conditions. Display patterns of chelipeds have an important role in agonistic and aggressive interactions. Of the five pairs of pereiopods, the chelae are versatile organs of offence and defence which also make them the most vulnerable for autotomy. Regeneration of the autotomized chelipeds imposes an additional energy demand called “regeneration load” on the incumbent, altering energy allocation for somatic and/or reproductive processes. Partial withdrawal of chelae leading to incomplete exuviation is reported for the first time in the laboratory and field in Macrobrachium species.

  1. A vaccine encoding conserved promiscuous HIV CD4 epitopes induces broad T cell responses in mice transgenic to multiple common HLA class II molecules.

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    Susan Pereira Ribeiro

    Full Text Available Current HIV vaccine approaches are focused on immunogens encoding whole HIV antigenic proteins that mainly elicit cytotoxic CD8+ responses. Mounting evidence points toward a critical role for CD4+ T cells in the control of immunodeficiency virus replication, probably due to cognate help. Vaccine-induced CD4+ T cell responses might, therefore, have a protective effect in HIV replication. In addition, successful vaccines may have to elicit responses to multiple epitopes in a high proportion of vaccinees, to match the highly variable circulating strains of HIV. Using rational vaccine design, we developed a DNA vaccine encoding 18 algorithm-selected conserved, "promiscuous" (multiple HLA-DR-binding B-subtype HIV CD4 epitopes - previously found to be frequently recognized by HIV-infected patients. We assessed the ability of the vaccine to induce broad T cell responses in the context of multiple HLA class II molecules using different strains of HLA class II- transgenic mice (-DR2, -DR4, -DQ6 and -DQ8. Mice displayed CD4+ and CD8+ T cell responses of significant breadth and magnitude, and 16 out of the 18 encoded epitopes were recognized. By virtue of inducing broad responses against conserved CD4+ T cell epitopes that can be recognized in the context of widely diverse, common HLA class II alleles, this vaccine concept may cope both with HIV genetic variability and increased population coverage. The vaccine may thus be a source of cognate help for HIV-specific CD8+ T cells elicited by conventional immunogens, in a wide proportion of vaccinees.

  2. Biomineralizations: insights and prospects from crustaceans

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    Gilles Luquet

    2012-03-01

    Full Text Available For growing, crustaceans have to molt cyclically because of the presence of a rigid exoskeleton. Most of the crustaceans harden their cuticle not only by sclerotization, like all the arthropods, but also by calcification. All the physiology of crustaceans, including the calcification process, is then linked to molting cycles. This means for these animals to find regularly a source of calcium ions quickly available just after ecdysis. The sources of calcium used are diverse, ranging from the environment where the animals live to endogenous calcium deposits cyclically elaborated by some of them. As a result, crustaceans are submitted to an important and energetically demanding calcium turnover throughout their life. The mineralization process occurs by precipitation of calcium carbonate within an organic matrix network of chitin-proteins fibers. Both crystalline and stabilized amorphous polymorphs of calcium carbonate are found in crustacean biominerals. Furthermore, Crustacea is the only phylum of animals able to elaborate and resorb periodically calcified structures. Notably for these two previous reasons, crustaceans are more and more extensively studied and considered as models of choice in the biomineralization research area.

  3. Conserved synthetic peptides from the hemagglutinin of influenza viruses induce broad humoral and T-cell responses in a pig model.

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    Júlia Vergara-Alert

    Full Text Available Outbreaks involving either H5N1 or H1N1 influenza viruses (IV have recently become an increasing threat to cause potential pandemics. Pigs have an important role in this aspect. As reflected in the 2009 human H1N1 pandemia, they may act as a vehicle for mixing and generating new assortments of viruses potentially pathogenic to animals and humans. Lack of universal vaccines against the highly variable influenza virus forces scientists to continuously design vaccines à la carte, which is an expensive and risky practice overall when dealing with virulent strains. Therefore, we focused our efforts on developing a broadly protective influenza vaccine based on the Informational Spectrum Method (ISM. This theoretical prediction allows the selection of highly conserved peptide sequences from within the hemagglutinin subunit 1 protein (HA1 from either H5 or H1 viruses which are located in the flanking region of the HA binding site and with the potential to elicit broader immune responses than conventional vaccines. Confirming the theoretical predictions, immunization of conventional farm pigs with the synthetic peptides induced humoral responses in every single pig. The fact that the induced antibodies were able to recognize in vitro heterologous influenza viruses such as the pandemic H1N1 virus (pH1N1, two swine influenza field isolates (SwH1N1 and SwH3N2 and a H5N1 highly pathogenic avian virus, confirm the broad recognition of the antibodies induced. Unexpectedly, all pigs also showed T-cell responses that not only recognized the specific peptides, but also the pH1N1 virus. Finally, a partial effect on the kinetics of virus clearance was observed after the intranasal infection with the pH1N1 virus, setting forth the groundwork for the design of peptide-based vaccines against influenza viruses. Further insights into the understanding of the mechanisms involved in the protection afforded will be necessary to optimize future vaccine formulations.

  4. Intersite epibiosis characterization on dominant mangrove crustacean species from Malaysia

    NARCIS (Netherlands)

    Fernandez-Leborans, G.; Hanamura, Y.; Siow, R.; Chee, P.-E.

    2009-01-01

    Epibiosis was studied in dominant mangrove crustacean species in several areas in Malaysia. The observed basibionts were the crustaceans Mesopodopsis orientalis, Acetes japonicus, Acetes sibogae, Acetes indicus and Fenneropenaeus merguiensis and the epibionts found were the protozoan ciliates Acinet

  5. Carotenoids in Aquaculture: Fish and Crustaceans

    Science.gov (United States)

    Bjerkeng, Bjorn

    This Chapter deals with selected topics on the use of carotenoids for colouration in aquaculture and incudes examples from ecological studies which support our understanding of functions and actions of carotenoids and colouration in fishes and crustaceans. Animal colours may be physical or structural in origin [1], e.g. Tyndall blues and iridescent diffraction colours, or they may be due to pigments, including carotenoids (Chapter 10).

  6. De novo assembly and characterization of a maternal and developmental transcriptome for the emerging model crustacean Parhyale hawaiensis

    Directory of Open Access Journals (Sweden)

    Zeng Victor

    2011-11-01

    Full Text Available Abstract Background Arthropods are the most diverse animal phylum, but their genomic resources are relatively few. While the genome of the branchiopod Daphnia pulex is now available, no other large-scale crustacean genomic resources are available for comparison. In particular, genomic resources are lacking for the most tractable laboratory model of crustacean development, the amphipod Parhyale hawaiensis. Insight into shared and divergent characters of crustacean genomes will facilitate interpretation of future developmental, biomedical, and ecological research using crustacean models. Results To generate a transcriptome enriched for maternally provided and zygotically transcribed developmental genes, we created cDNA from ovaries and embryos of P. hawaiensis. Using 454 pyrosequencing, we sequenced over 1.1 billion bases of this cDNA, and assembled them de novo to create, to our knowledge, the second largest crustacean genomic resource to date. We found an unusually high proportion of C2H2 zinc finger-containing transcripts, as has also been reported for the genome of the pea aphid Acyrthosiphon pisum. Consistent with previous reports, we detected trans-spliced transcripts, but found that they did not noticeably impact transcriptome assembly. Our assembly products yielded 19,067 unique BLAST hits against nr (E-value cutoff e-10. These included over 400 predicted transcripts with significant similarity to D. pulex sequences but not to sequences of any other animal. Annotation of several hundred genes revealed P. hawaiensis homologues of genes involved in development, gametogenesis, and a majority of the members of six major conserved metazoan signaling pathways. Conclusions The amphipod P. hawaiensis has higher transcript complexity than known insect transcriptomes, and trans-splicing does not appear to be a major contributor to this complexity. We discuss the importance of a reliable comparative genomic framework within which to consider findings

  7. Nuclear Magnetic Resonance Solution Structures of Lacticin Q and Aureocin A53 Reveal a Structural Motif Conserved among Leaderless Bacteriocins with Broad-Spectrum Activity.

    Science.gov (United States)

    Acedo, Jeella Z; van Belkum, Marco J; Lohans, Christopher T; Towle, Kaitlyn M; Miskolzie, Mark; Vederas, John C

    2016-02-01

    Lacticin Q (LnqQ) and aureocin A53 (AucA) are leaderless bacteriocins from Lactococcus lactis QU5 and Staphylococcus aureus A53, respectively. These bacteriocins are characterized by the absence of an N-terminal leader sequence and are active against a broad range of Gram-positive bacteria. LnqQ and AucA consist of 53 and 51 amino acids, respectively, and have 47% identical sequences. In this study, their three-dimensional structures were elucidated using solution nuclear magnetic resonance and were shown to consist of four α-helices that assume a very similar compact, globular overall fold (root-mean-square deviation of 1.7 Å) with a highly cationic surface and a hydrophobic core. The structures of LnqQ and AucA resemble the shorter two-component leaderless bacteriocins, enterocins 7A and 7B, despite having low levels of sequence identity. Homology modeling revealed that the observed structural motif may be shared among leaderless bacteriocins with broad-spectrum activity against Gram-positive organisms. The elucidated structures of LnqQ and AucA also exhibit some resemblance to circular bacteriocins. Despite their similar overall fold, inhibition studies showed that LnqQ and AucA have different antimicrobial potency against the Gram-positive strains tested, suggesting that sequence disparities play a crucial role in their mechanisms of action. PMID:26771761

  8. A human antibody recognizing a conserved epitope of H5 hemagglutinin broadly neutralizes highly pathogenic avian influenza H5N1 viruses.

    Science.gov (United States)

    Hu, Hongxing; Voss, Jarrod; Zhang, Guoliang; Buchy, Philippi; Zuo, Teng; Wang, Lulan; Wang, Feng; Zhou, Fan; Wang, Guiqing; Tsai, Cheguo; Calder, Lesley; Gamblin, Steve J; Zhang, Linqi; Deubel, Vincent; Zhou, Boping; Skehel, John J; Zhou, Paul

    2012-03-01

    Influenza A virus infection is a persistent threat to public health worldwide due to its ability to evade immune surveillance through rapid genetic drift and shift. Current vaccines against influenza A virus provide immunity to viral isolates that are similar to vaccine strains. High-affinity neutralizing antibodies against conserved epitopes could provide immunity to diverse influenza virus strains and protection against future pandemic viruses. In this study, by using a highly sensitive H5N1 pseudotype-based neutralization assay to screen human monoclonal antibodies produced by memory B cells from an H5N1-infected individual and molecular cloning techniques, we developed three fully human monoclonal antibodies. Among them, antibody 65C6 exhibited potent neutralization activity against all H5 clades and subclades except for subclade 7.2 and prophylactic and therapeutic efficacy against highly pathogenic avian influenza H5N1 viruses in mice. Studies on hemagglutinin (HA)-antibody complexes by electron microscopy and epitope mapping indicate that antibody 65C6 binds to a conformational epitope comprising amino acid residues at positions 118, 121, 161, 164, and 167 (according to mature H5 numbering) on the tip of the membrane-distal globular domain of HA. Thus, we conclude that antibody 65C6 recognizes a neutralization epitope in the globular head of HA that is conserved among almost all divergent H5N1 influenza stains. PMID:22238297

  9. Conservation = Conservation

    OpenAIRE

    Daget, Jacques; Gaigher, I.C.; Ssentongo, G.W.

    1988-01-01

    African freshwater fishes are endangered by over exploitation of live fish for aquarists and for exports, intensive fishing of species with low resilience, introduction of exotic species, pollution, general environmental modification by man. Therefore, to ensure conservation to fish species, it is necessary to increase basic knowledge in order to provide guidelines and a scientific basis for conservation measures. The three main lines for the development of a fish conservation policy are publ...

  10. Ultraviolet filters in stomatopod crustaceans: diversity, ecology and evolution.

    Science.gov (United States)

    Bok, Michael J; Porter, Megan L; Cronin, Thomas W

    2015-07-01

    Stomatopod crustaceans employ unique ultraviolet (UV) optical filters in order to tune the spectral sensitivities of their UV-sensitive photoreceptors. In the stomatopod species Neogonodactylus oerstedii, we previously found four filter types, produced by five distinct mycosporine-like amino acid pigments in the crystalline cones of their specialized midband ommatidial facets. This UV-spectral tuning array produces receptors with at least six distinct spectral sensitivities, despite expressing only two visual pigments. Here, we present a broad survey of these UV filters across the stomatopod order, examining their spectral absorption properties in 21 species from seven families in four superfamilies. We found that UV filters are present in three of the four superfamilies, and evolutionary character reconstruction implies that at least one class of UV filter was present in the ancestor of all modern stomatopods. Additionally, postlarval stomatopods were observed to produce the UV filters simultaneously alongside development of the adult eye. The absorbance properties of the filters are consistent within a species; however, between species we found a great deal of diversity, both in the number of filters and in their spectral absorbance characteristics. This diversity correlates with the habitat depth ranges of these species, suggesting that species living in shallow, UV-rich environments may tune their UV spectral sensitivities more aggressively. We also found additional, previously unrecognized UV filter types in the crystalline cones of the peripheral eye regions of some species, indicating the possibility for even greater stomatopod visual complexity than previously thought. PMID:25964422

  11. Calcium phosphate mineralization is widely applied in crustacean mandibles

    OpenAIRE

    Shmuel Bentov; Aflalo, Eliahu D.; Jenny Tynyakov; Lilah Glazer; Amir Sagi

    2016-01-01

    Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, crayfishes, prawns and shrimps) shifted toward the formation of calcium phosphate as the main mineral at specified locations of the mandibular teeth. In these structures, calcium phosphate is not merely co-precipitated with the bulk calcium carbonate but rather creates speciali...

  12. Alien terrestrial crustaceans (Isopods and Amphipods). Chapter 7.1

    OpenAIRE

    Pierre-Olivier Cochard; Ferenc Vilisics; Emmanuel Sechet

    2010-01-01

    A total of 17 terrestrial crustacean species aliens to Europe of which 13 isopods (woodlice) and 4 amphipods (lawn shrimps) have established on the continent. In addition, 21 species native to Europe were introduced in a European region to which they are not native. The establishment of alien crustacean species in Europe slowly increased during the 20th century without any marked changes during the recent decades. Almost all species alien to Europe originate from sub-tropical or tropical ar...

  13. Structure-activity relationship of crustacean peptide hormones.

    Science.gov (United States)

    Katayama, Hidekazu

    2016-04-01

    In crustaceans, various physiological events, such as molting, vitellogenesis, and sex differentiation, are regulated by peptide hormones. To understanding the functional sites of these hormones, many structure-activity relationship (SAR) studies have been published. In this review, the author focuses the SAR of crustacean hyperglycemic hormone-family peptides and androgenic gland hormone and describes the detailed results of our and other research groups. The future perspectives will be also discussed. PMID:26624010

  14. Outlining eicosanoid biosynthesis in the crustacean Daphnia

    Directory of Open Access Journals (Sweden)

    Timmermans Martijn JTN

    2008-07-01

    Full Text Available Abstract Background Eicosanoids are biologically active, oxygenated metabolites of three C20 polyunsaturated fatty acids. They act as signalling molecules within the autocrine or paracrine system in both vertebrates and invertebrates mainly functioning as important mediators in reproduction, the immune system and ion transport. The biosynthesis of eicosanoids has been intensively studied in mammals and it is known that they are synthesised from the fatty acid, arachidonic acid, through either the cyclooxygenase (COX pathway; the lipoxygenase (LOX pathway; or the cytochrome P450 epoxygenase pathway. However, little is still known about the synthesis and structure of the pathway in invertebrates. Results Here, we show transcriptomic evidence from Daphnia magna (Crustacea: Branchiopoda together with a bioinformatic analysis of the D. pulex genome providing insight on the role of eicosanoids in these crustaceans as well as outlining a putative pathway of eicosanoid biosynthesis. Daphnia appear only to have one copy of the gene encoding the key enzyme COX, and phylogenetic analysis reveals that the predicted protein sequence of Daphnia COX clusters with other invertebrates. There is no current evidence of an epoxygenase pathway in Daphnia; however, LOX products are most certainly synthesised in daphnids. Conclusion We have outlined the structure of eicosanoid biosynthesis in Daphnia, a key genus in freshwater ecosystems. Improved knowledge of the function and synthesis of eicosanoids in Daphnia and other invertebrates could have important implications for several areas within ecology. This provisional overview of daphnid eicosanoid biosynthesis provides a guide on where to focus future research activities in this area.

  15. Behavioural indicators of pain in crustacean decapods

    Directory of Open Access Journals (Sweden)

    Francesca Gherardi

    2009-12-01

    Full Text Available Whether invertebrates are able or not to experience pain is a highly controversial issue. An operative way to solve such a controversy might be to investigate their responses to potentially noxious stimuli and to collect evidence of their behavioural complexities as proxies of cognitive capacities. The principle of argument-by-analogy can be then applied to these data: the behaviour displayed by invertebrates is compared with that of "higher" animals, its similarity denoting the former's capacity to have analogous experiences. Here, the author discusses some examples, extracted from the literature on crustacean decapods, that pinpoint their nature of "sentient" animals. This review, however, also shows that research is still scanty in the field. The studies that examine the potential links between stress responses and pain experience are few, and the several papers that help elucidate cognitive abilities in decapods have been limited to a few taxa and are not specifically directed to the question of "sentience". On the contrary, also in the light of the expected revision of the current EU legislation in the matter, more scientific efforts should be expended on exploring the issue of pain experience in invertebrates.

  16. Crustacean hyperglycemic hormone (cHH as a modulator of aggression in crustacean decapods.

    Directory of Open Access Journals (Sweden)

    Laura Aquiloni

    Full Text Available Biogenic amines, particularly serotonin, are recognised to play an important role in controlling the aggression of invertebrates, whereas the effect of neurohormones is still underexplored. The crustacean Hyperglycemic Hormone (cHH is a multifunctional member of the eyestalk neuropeptide family. We expect that this neuropeptide influences aggression either directly, by controlling its expression, or indirectly, by mobilizing the energetic stores needed for the increased activity of an animal. Our study aims at testing such an influence and the possible reversion of hierarchies in the red swamp crayfish, Procambarus clarkii, as a model organism. Three types of pairs of similarly sized males were formed: (1 'control pairs' (CP, n = 8: both individuals were injected with a phosphate saline solution (PBS; (2 'reinforced pairs' (RP, n = 9: the alpha alone was injected with native cHH, and the beta with PBS; (3 'inverted pairs' (IP, n = 9: the opposite of (2. We found that, independently of the crayfish's prior social experience, cHH injections induced (i the expression of dominance behaviour, (ii higher glycemic levels, and (iii lower time spent motionless. In CP and RP, fight intensity decreased with the establishment of dominance. On the contrary, in IP, betas became increasingly likely to initiate and escalate fights and, consequently, increased their dominance till a temporary reversal of the hierarchy. Our results demonstrate, for the first time, that, similarly to serotonin, cHH enhances individual aggression, up to reverse, although transitorily, the hierarchical rank. New research perspectives are thus opened in our intriguing effort of understanding the role of cHH in the modulation of agonistic behaviour in crustaceans.

  17. Computational analysis of molt-inhibiting hormone from selected crustaceans.

    Science.gov (United States)

    C, Kumaraswamy Naidu; Y, Suneetha; P, Sreenivasula Reddy

    2013-12-01

    Molt-inhibiting hormone (MIH) is a principal endocrine hormone regulating the growth in crustaceans. In total, nine MIH peptide sequences representing members of the family Penaeidae (Penaeus monodon, Litopenaeus vannamei, Marsupenaeus japonicus), Portunidae (Portunus trituberculatus, Charybdis japonica, Charybdis feriata), Cambaridae (Procambarus bouvieri), Parastacidae (Cherax quadricarinatus) and Varunidae (Eriocheir sinensis) were selected for our study. In order to develop a structure based phylogeny, predict functionally important regions and to define stability changes upon single site mutations, the 3D structure of MIH for the crustaceans were built by using homology modeling based on the known structure of MIH from M. japonicus (1J0T). Structure based phylogeny showed a close relationship between P. bouvieri and C. japonica. ConSurf server analysis showed that the residues Cys(8), Arg(15), Cys(25), Asp(27), Cys(28), Asn(30), Arg(33), Cys(41), Cys(45), Phe(51), and Cys(54) may be functionally significant among the MIH of crustaceans. Single amino acid substitutions 'Y' and 'G' at the positions 71 and 72 of the MIH C-terminal region showed an alteration in the stability indicating that a change in this region may alter the function of MIH. In conclusion, we proposed a computational approach to analyze the structure, phylogeny and stability of MIH from crustaceans. PMID:24041714

  18. Modelling gastric evacuation in gadoids feeding on crustaceans.

    Science.gov (United States)

    Andersen, N G; Chabot, D; Couturier, C S

    2016-05-01

    A mechanistic, prey surface-dependent model was expanded to describe the course and rate of gastric evacuation in predatory fishes feeding on crustacean prey with robust exoskeletons. This was accomplished by adding a layer of higher resistance to the digestive processes outside the inner softer parts of a prey cylinder abstraction and splitting up the prey evacuation into two stages: an initial stage where the exoskeleton is cracked and a second where the prey remains are digested and evacuated. The model was parameterized for crustaceans with different levels of armour fed to Atlantic cod Gadus morhua or whiting Merlangius merlangus and recovered from the stomachs at different post-prandial times. The prey species were krill Meganyctiphanes norvegica; shrimps and prawns Crangon crangon, Pandalus borealis, Pandalus montagui and Eualus macilentus; crabs Liocarcinus depurator and Chionoecetes opilio. In accordance with the apparent intraspecific isometric relationship between exoskeleton mass and total body mass, the model described stage duration and rate of evacuation of the crustacean prey independently of meal and prey sizes. The duration of the first stage increased (0-33 h) and the evacuation rate of both stages decreased (by a half) with increasing level of the crustacean armament in terms of chitin and ash. A common, interspecific parameterization of the model within each of the categories krill, shrimp and crab can probably be used if the contents of chitin and ash are similar among prey species per prey category. The model offers a simple way for estimating evacuation rates from stomach content data in order to obtain food consumption rates of wild fishes, provided that information about digestion stage of crustacean prey is available. PMID:27170110

  19. High sequence variability among hemocyte-specific Kazal-type proteinase inhibitors in decapod crustaceans.

    Science.gov (United States)

    Cerenius, Lage; Liu, Haipeng; Zhang, Yanjiao; Rimphanitchayakit, Vichien; Tassanakajon, Anchalee; Gunnar Andersson, M; Söderhäll, Kenneth; Söderhäll, Irene

    2010-01-01

    Crustacean hemocytes were found to produce a large number of transcripts coding for Kazal-type proteinase inhibitors (KPIs). A detailed study performed with the crayfish Pacifastacus leniusculus and the shrimp Penaeus monodon revealed the presence of at least 26 and 20 different Kazal domains from the hemocyte KPIs, respectively. Comparisons with KPIs from other taxa indicate that the sequences of these domains evolve rapidly. A few conserved positions, e.g. six invariant cysteines were present in all domain sequences whereas the position of P1 amino acid, a determinant for substrate specificity, varied highly. A study with a single crayfish animal suggested that even at the individual level considerable sequence variability among hemocyte KPIs produced exist. Expression analysis of four crayfish KPI transcripts in hematopoietic tissue cells and different hemocyte types suggest that some of these KPIs are likely to be involved in hematopoiesis or hemocyte release as they were produced in particular hemocyte types or maturation stages only. PMID:19715720

  20. Detection of tropomyosin and determination of proteins in crustacean oils.

    Science.gov (United States)

    Vang, Birthe; Mæhre, Hanne K; Jensen, Ida-J; Olsen, Ragnar L

    2013-11-01

    Tropomyosin is known to be the main allergen in crustaceans and the objective of this study was to investigate if this protein could be detected in commercial crustacean oils from Antarctic krill (Euphausia superba) and the zooplankton Calanus finmarchicus. We also examined the possibility of determining the protein content in the oils by direct amino acid analysis. Western blotting showed that a commercial antibody against shrimp tropomyosin cross-reacted with a protein of similar size in Antarctic krill and C. finmarchicus. The protein tentatively identified as tropomyosin, was also detected in krill oil products, but not in oils from C. finmarchicus. The acetone-heptane method used for extracting proteins in the oils is however not optimal. Other extraction methods should therefore be considered when investigating the presence of allergenic proteins in oils. Direct amino acid analysis on oils should be further explored as a method for determining the total amount of proteins present. PMID:23768329

  1. Crustaceans as a model for microgravity-induced muscle atrophy

    Science.gov (United States)

    Mykles, D. L.

    Atrophy of skeletal muscles is a serious problem in a microgravity environment. It is hypothesized that the unloading of postural muscles, which no longer must resist gravity force, causes an accelerated breakdown of contractile proteins, resulting in a reduction in muscle mass and strength. A crustacean model using the land crab, Gecarcinus lateralis, to assess the effects of spaceflight on protein metabolism is presented. The model is compared to a developmentally-regulated atrophy in which a premolt reduction in muscle mass allows the withdrawal of the large claws at molt. The biochemical mechanisms underlying protein breakdown involves both Ca^2+-dependent and multicatalytic proteolytic enzymes. Crustacean claw muscle can be used to determine the interactions between shortening and unloading at the molecular level.

  2. The role of lysosomal cysteine proteases in crustacean immune response

    Directory of Open Access Journals (Sweden)

    FL Garcia-Carreño

    2014-04-01

    Full Text Available Over the long course of evolution and under the selective pressure exerted by pathogens and parasites, animals have selectively fixed a number of defense mechanisms against the constant attack of intruders. The immune response represents a key component to optimize the biological fitness of individuals. Two decades ago, prevention and control of diseases in crustacean aquaculture systems were considered priorities in most shrimp-producing countries, but knowledge was scarce and various pathogens have severely affected aquaculture development around the world. Scientific contributions have improved our understanding of the crustacean immune response. Several studies confirm the central role played by proteases in the immune response of animals, and the cooperative interaction of these enzymes in a wide variety of organisms is well known. This review summarizes the current information regarding the role of cysteine proteases in the immune system of Crustacea and points to aspects that are needed to provide a better integration of our knowledge.

  3. Alien terrestrial crustaceans (Isopods and Amphipods. Chapter 7.1

    Directory of Open Access Journals (Sweden)

    Pierre-Olivier Cochard

    2010-07-01

    Full Text Available A total of 17 terrestrial crustacean species aliens to Europe of which 13 isopods (woodlice and 4 amphipods (lawn shrimps have established on the continent. In addition, 21 species native to Europe were introduced in a European region to which they are not native. The establishment of alien crustacean species in Europe slowly increased during the 20th century without any marked changes during the recent decades. Almost all species alien to Europe originate from sub-tropical or tropical areas. Most of the initial introductions were recorded in greenhouses, botanical gardens and urban parks, probably associated with passive transport of soil, plants or compost. Alien woodlice are still confined to urban habitats. Natural habitats have only been colonized by three amphipod species in the family Talitridade.

  4. Contributions of larval biology to crustacean research: a review

    OpenAIRE

    Anger, Klaus

    2006-01-01

    Many aquatic crustaceans pass through a complex life cycle comprising a benthic juvenile-adult and a pelagic larval phase. In the study of aquatic ecology, meroplanktonic larvae are therefore considered as principal components of benthic-pelagic coupling processes. As a consequence of radical transitions of life style, larvae differ from conspecific adults in their ecology, behaviour, nutrition, morphology, and physiology. Ontogenetic changes of these traits, as well as carry-over effects of ...

  5. Evolution and development in cave animals: from fish to crustaceans

    OpenAIRE

    Protas, Meredith; Jeffery, William R.

    2012-01-01

    Cave animals are excellent models to study the general principles of evolution as well as the mechanisms of adaptation to a novel environment: the perpetual darkness of caves. In this article, two of the major model systems used to study the evolution and development (evo–devo) of cave animals are described: the teleost fish Astyanax mexicanus and the isopod crustacean Asellus aquaticus. The ways in which these animals match the major attributes expected of an evo–devo cave animal model syste...

  6. SHELF LIFE OF THAWED CRUSTACEANS TREATED WITH SULPHITES

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    G. Smaldone

    2011-04-01

    Full Text Available The quality of fish and fish products is closely related to their freshness. Aim of this research was to evaluate the shelf life of thawed crustaceans (Aristeomorpha foliacea and Nefrops norvegicus which had been treated with sulphites and frozen on board. Organoleptic characteristics and microbiological and chemical parameters were judged favourably up to day 6 and 7 for the shrimps and Norway lobsters, respectively.

  7. Biological Studies on groundwater Crustaceans in Southwest Anatolia, Turkey

    OpenAIRE

    Könemann, Stefan

    1997-01-01

    In 1987 a major biospeleogical expedition, ‘Speleo Nederland’, was carried out along the coastal Taurus mountains in southwest Anatolia (Turkey). ‘Speleo Nederland’ was focused on collecting the fauna of caves, wells, subterranean waterflows, and the interstices of marine gravel beaches. The special yield of stygobiont crustaceans, predominantly amphipods of the genus Bogidiella, promised to serve as an interesting case study to the colonization of inland groundwater by marine organisms. Now,...

  8. The Feeding Morphology and Ecology of Stomatopod Crustaceans

    OpenAIRE

    Devries, Maya Susanna

    2012-01-01

    The paradigm that animals with specialized feeding morphology consume specific prey types is central to current understanding of ecological and evolutionary processes seen in nature. Mantis shrimp, or stomatopod crustaceans, are often hailed as having highly specialized feeding morphology; their raptorial appendages produce among the fastest, most powerful strikes ever reported in the animal kingdom, allowing species to capture fast-moving prey or to crush hard-shelled prey. While all stoma...

  9. Decapod crustaceans from the Paleocene of Central Texas, USA

    OpenAIRE

    Adam Armstrong; Torrey Nyborg; Gale A. Bishop; Àlex Ossó-Morales; Vega, Francisco J.

    2009-01-01

    Fourteen species of decapods crustaceans are described from a single locality near Mexia, Texas, where Paleocene sediments of the Mexia Clay Member of the Wills Point Formation crop out. The species are represented by Hoploparia sp., Linuparus wilcoxensis Rathbun, 1935, an unnamed paguroid, Kierionopsis nodosa Davidson, 1966, Pithonoton cardwelli new species, Caloxanthus sp., Macroacaena johnsoni (Rathbun, 1935), new combination, Raninoides bournei (Rathbun, 1928), R. treldenaesensis (Collins...

  10. Toxicity of five anilines to crustaceans, protozoa and bacteria

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    MARILIIS SIHTMÄE

    2010-09-01

    Full Text Available Aromatic amines (anilines and related derivates are an important class of environmental pollutants that can be released to the aquatic environment as industrial effluents or as breakdown products of pesticides and dyes. The toxicity of aniline, 2-chloroaniline, 3-chloroaniline, 4-chloroaniline and 3,5-dichloroaniline towards a multitrophic test battery comprised of bacteria Aliivibrio fischeri (formerly Vibrio fischeri, a ciliated protozoan Tetrahymena thermophila and two crustaceans (Daphnia magna and Thamnocephalus platyurus were investigated. Under the applied test conditions, the toxicity of the anilines notably varied among the test species. The bacteria and protozoa were much less sensitive towards the anilines than the crustaceans: EC50 values 13–403 mg L-1 versus 0.13–15.2 mg L-1. No general tendency between toxicity and the chemical structure of the anilines (the degree of chloro-substitution and the position of the chloro-substituents was found in the case of all the tested aquatic species. The replacement of the artificial test medium (ATM by the river water remarkably decreased the toxicity of anilines to crustaceans but not to protozoa. This research is part of the EU 6th Framework Integrated Project OSIRIS, in which ecotoxicogenomic studies of anilines (e.g., for Daphnia magna will also be performed that may help to clarify the mechanisms of toxicity of different anilines.

  11. Crustacean fauna of a mussel cultivated raft system in the Black Sea

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    Murat Sezgin

    2013-06-01

    Full Text Available The aim of the current study was to make a faunistic analysis of the crustaceans associated with cultivated mussels grown on ropes. Mussel samples from 30 cm ropes were collected from rope-grown mussel beds by hand. The crustacean fauna associated with mussel population were quantified. The density of crustacean fauna associated with mussels was significantly greater within rope-grown mussel assemblages than on other biotopes around.

  12. The First Complete Mitochondrial Genome Sequences for Stomatopod Crustaceans: Implications for Phylogeny

    Energy Technology Data Exchange (ETDEWEB)

    Swinstrom, Kirsten; Caldwell, Roy; Fourcade, H. Matthew; Boore, Jeffrey L.

    2005-09-07

    We report the first complete mitochondrial genome sequences of stomatopods and compare their features to each other and to those of other crustaceans. Phylogenetic analyses of the concatenated mitochondrial protein-coding sequences were used to explore relationships within the Stomatopoda, within the malacostracan crustaceans, and among crustaceans and insects. Although these analyses support the monophyly of both Malacostraca and, within it, Stomatopoda, it also confirms the view of a paraphyletic Crustacea, with Malacostraca being more closely related to insects than to the branchiopod crustaceans.

  13. The 2010 Broad Prize

    Science.gov (United States)

    Education Digest: Essential Readings Condensed for Quick Review, 2011

    2011-01-01

    A new data analysis, based on data collected as part of The Broad Prize process, provides insights into which large urban school districts in the United States are doing the best job of educating traditionally disadvantaged groups: African-American, Hispanics, and low-income students. Since 2002, The Eli and Edythe Broad Foundation has awarded The…

  14. The impact of pathogens on exploited populations of decapod crustaceans.

    Science.gov (United States)

    Shields, Jeffrey D

    2012-06-01

    Several crustacean fisheries have experienced significant outbreaks of disease that have damaged their industries. Not only do fisheries suffer from direct losses to pathogens, such as disease-induced mortalities or reduced product value, but they can also incur indirect losses such as stunting, castration, and increased risk of predation. In some cases, the indirect losses can be substantial, yet they are often overlooked by the fishing industry as their primary focus is on recruits to the fishery, and not on the affected juvenile pre-recruits. Low levels of pathogens are to be expected in natural populations of commercial species, but baseline data on the prevalence and intensity of even the most common agents is often lacking. It is important to establish baselines for two reasons. First, it is important to know what pathogens exist in heavily exploited populations so as to gauge their potential to damage the industry; and second, during outbreaks, it is important to know whether an outbreak is a newly emergent event or whether it is a component of a cyclical phenomenon. Pathogens frequently act in concert with environmental stressors, and a variety of stressors have contributed to outbreaks of emerging agents in crustacean fisheries. Pollution, poor water quality, hypoxia, temperature extremes, and overexploitation have all been implicated as stressors in various outbreaks. This review focuses on epidemic diseases of commercially fished crustaceans. Outbreaks in cultured stocks are not covered. Disease epizootics have occurred in fished populations of crayfish and shrimp but they are less well known than the issues arising from extensive aquaculture of these species. PMID:22434001

  15. MIO-PLIOCENE CRUSTACEANS FROM THE CANARY ISLANDS, SPAIN

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    JUAN FRANCISCO BETANCORT

    2014-11-01

    Full Text Available There are few previous references to fossil crustaceans for the Neogene marine layers of the Canary Islands (Spain. The Mio-Pliocene marine sedimentary layers in the eastern islands (Gran Canaria, Fuerteventura and Lanzarote were previously characterised by the presence of numerous fossil fauna, mainly anthozoans and molluscs, which correspond to an equatorial-typepalaeoclimate, warmer than the present climate. This Mio-Pliocene transition dated between 9.3 and 4.1 Ma. In this paper, 12 fossil crustacean taxa are identified and classified, including decapods and barnacles: Balanus concavus Bronn, 1831, Balanus spongicola Brown, 1827, Balanus perforatus Bruguière, 1789, Chenolobia testudinaria Linnè, 1767, Tetraclita cf. rubescens Darwin, 1854, Callianassa matsoni Rathbun, 1935, Callianassa sp., Upogebia sp, Eriphia aff. verrucosa (Forskal, 1775 , Maja sp., Scylla michelini Milne-Edwards, 1861 and Ocypode sp. Some of these taxa mean new references for the Atlantic islands and the North African Atlantic and definitely enlarge the palaeographic distribution of Neogene crustaceans beyond the Mediterranean region, extending it to the North Atlantic. Particularly significant are the presence of Tetraclita cf. rubescens ,this being the first reported fossil occurrence of this barnacle outside the North America Pacific coasts, and Chenolobia testudinaria , indicating for the first time the existence of marine turtles in these islands during the Neogene. These results are coherent with previous research hypothesising the existence of a flow of surface water between the Pacific and Atlantic in the Mio-Pliocene transition (Central American Seaway, CAS which explains the arrival of organisms, in larval stage, from Central America to the Canary Islands.

  16. Molecular, Biochemical, and Dietary Regulation Features of α-Amylase in a Carnivorous Crustacean, the Spiny Lobster Panulirus argus

    Science.gov (United States)

    Martos-Sitcha, Juan Antonio; Perdomo-Morales, Rolando; Casuso, Antonio; Montero-Alejo, Vivian; García-Galano, Tsai; Martínez-Rodríguez, Gonzalo; Mancera, Juan Miguel

    2016-01-01

    Alpha-amylases are ubiquitously distributed throughout microbials, plants and animals. It is widely accepted that omnivorous crustaceans have higher α-amylase activity and number of isoforms than carnivorous, but contradictory results have been obtained in some species, and carnivorous crustaceans have been less studied. In addition, the physiological meaning of α-amylase polymorphism in crustaceans is not well understood. In this work we studied α-amylase in a carnivorous lobster at the gene, transcript, and protein levels. It was showed that α-amylase isoenzyme composition (i.e., phenotype) in lobster determines carbohydrate digestion efficiency. Most frequent α-amylase phenotype has the lowest digestion efficiency, suggesting this is a favoured trait. We revealed that gene and intron loss have occurred in lobster α-amylase, thus lobsters express a single 1830 bp cDNA encoding a highly conserved protein with 513 amino acids. This protein gives rise to two isoenzymes in some individuals by glycosylation but not by limited proteolysis. Only the glycosylated isoenzyme could be purified by chromatography, with biochemical features similar to other animal amylases. High carbohydrate content in diet down-regulates α-amylase gene expression in lobster. However, high α-amylase activity occurs in lobster gastric juice irrespective of diet and was proposed to function as an early sensor of the carbohydrate content of diet to regulate further gene expression. We concluded that gene/isoenzyme simplicity, post-translational modifications and low Km, coupled with a tight regulation of gene expression, have arose during evolution of α-amylase in the carnivorous lobster to control excessive carbohydrate digestion in the presence of an active α-amylase. PMID:27391425

  17. Decapod crustaceans associated with an artificial reef (Adriatic Sea

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    A. SANTELLI

    2013-07-01

    Full Text Available The aim of this study is to increase the knowledge on the distribution of decapod crustaceans associated with an artificial reef positioned on sandy-mud bottoms in the central Adriatic Sea. The reef is constituted of concrete modules assembled in pyramids and concrete poles. Hard and soft bottom samples were collected from 2001, just after reef construction, to 2005 (4 surveys per year. Regarding the soft seabed, three sites close to a pyramid, three inside the reef area at a distance of 10-15 m from the structures, and three 200 m outside the reef (control sites were randomly sampled during each survey. At the same time, three pyramids (vertical and horizontal walls and three poles were also investigated. After taxonomical analysis, decapod crustaceans were analysed using abundance and species richness. Sites and years were compared using a balanced, fixed effect, 2-way ANOVA and PERMANOVA. In addition, SIMPER analysis was performed to identify those species typifying each community inhabiting both the soft bottom and the artificial substrates. The results showed that the artificial reef induced an increase in both abundance and diversity of the decapods of the natural habitat. In fact, man-made substrates may offer new available space for biological colonization and allow the settlement of new species usually living on hard bottoms, thus increasing the complexity of the original benthic communities.

  18. Behavioral plasticity, behavioral syndromes and animal personality in crustacean decapods: An imperfect map is better than no map

    Institute of Scientific and Technical Information of China (English)

    Francesca GHERARDI; Laura AQUILONI; Elena TRICARICO

    2012-01-01

    Despite their key role as model organisms in many behavioral studies,crustacean decapods have been only slightly touched upon by the recent surge of scientific interest in animal personality.Only seven articles investigated the issue in a handful of species among hermit crabs,crabs,and crayfish.Obviously,a limited number of publications does not mean that personality is rare in decapods.On the contrary,few studies might be the result of a form of reluctance by behavioral ecologists to deal with such a phenomenon in these and other invertebrates.This reluctance contrasts with the enthusiasm shown in tackling the behavioral plasticity issue.Here we discuss the possible theoretical and methodological difficulties raised by applying the animal personality perspective to decapods and analyze implications of personality studies for their ecology,conservation,and welfare.By highlighting gaps in knowledge and directions of future research,our intention is to increase scientific emphasis on the issue.

  19. Endocrine regulation of the reproduction in crustaceans: Identification of potential targets for toxicants and environmental contaminants

    Czech Academy of Sciences Publication Activity Database

    Mazurová, E.; Hilscherová, Klára; Triebskorn, R.; Kohler, H.R.; Maršálek, Blahoslav; Bláha, Luděk

    2008-01-01

    Roč. 63, č. 2 (2008), s. 139-150. ISSN 0006-3088 Institutional research plan: CEZ:AV0Z60050516 Keywords : crustaceans * reproduction * endocrine disruption Subject RIV: EF - Botanics Impact factor: 0.406, year: 2008

  20. THE INFLUENCE OF INSECT JUVENILE HORMONE AGONISTTS ON METAMORPHOSIS AND REPRODUCTION IN ESTUARINE CRUSTACEANS

    Science.gov (United States)

    Comparative developmental and reproductive studies were performed on several species of estuarine crustaceans in response to three juvenile hormone agonists (JHAs) (methoprene, fenoxycarb, and pyriproxyfen). Larval development of the grass shrimp, Palaemonetes pugio, was greater ...

  1. Seasonal succession of crustacean zooplankton in Wular Lake of the Kashmir Himalaya

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    Shah Javaid Ahmad

    2013-01-01

    Full Text Available The present study was undertaken on Wular Lake, a Ramsar Site in Kashmir Himalaya, to study the seasonal succession of crustacean zooplankton from September 2010 to August 2011. A total of 42 crustacean taxa belonging to Cladocera (23, Copepoda (16 and Ostracoda (3 were identified at five different sampling sites. Among the crustaceans, Cladocera was numerically the most dominant group at sites III, IV and V, followed by Copepoda at sites I and II. On an average basis total crustacean density ranged from 416 ind./l in winter to 1567.6 ind./l in summer. On the basis of Sorensen’s similarity index, study sites IV and V showed close similarity (88.13%.

  2. Global diversity of marine isopods (except Asellota and crustacean symbionts.

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    Gary C B Poore

    Full Text Available The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10-1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species

  3. Global diversity of marine isopods (except Asellota and crustacean symbionts).

    Science.gov (United States)

    Poore, Gary C B; Bruce, Niel L

    2012-01-01

    The crustacean order Isopoda (excluding Asellota, crustacean symbionts and freshwater taxa) comprise 3154 described marine species in 379 genera in 37 families according to the WoRMS catalogue. The history of taxonomic discovery over the last two centuries is reviewed. Although a well defined order with the Peracarida, their relationship to other orders is not yet resolved but systematics of the major subordinal taxa is relatively well understood. Isopods range in size from less than 1 mm to Bathynomus giganteus at 365 mm long. They inhabit all marine habitats down to 7280 m depth but with few doubtful exceptions species have restricted biogeographic and bathymetric ranges. Four feeding categories are recognised as much on the basis of anecdotal evidence as hard data: detritus feeders and browsers, carnivores, parasites, and filter feeders. Notable among these are the Cymothooidea that range from predators and scavengers to external blood-sucking micropredators and parasites. Isopods brood 10-1600 eggs depending on individual species. Strong sexual dimorphism is characteristic of several families, notably in Gnathiidae where sessile males live with a harem of females while juvenile praniza stages are ectoparasites of fish. Protandry is known in Cymothoidae and protogyny in Anthuroidea. Some Paranthuridae are neotenous. About half of all coastal, shelf and upper bathyal species have been recorded in the MEOW temperate realms, 40% in tropical regions and the remainder in polar seas. The greatest concentration of temperate species is in Australasia; more have been recorded from temperate North Pacific than the North Atlantic. Of tropical regions, the Central Indo-Pacific is home to more species any other region. Isopods are decidedly asymmetrical latitudinally with 1.35 times as many species in temperate Southern Hemisphere than the temperate North Atlantic and northern Pacific, and almost four times as many Antarctic as Arctic species. More species are known from the

  4. Application of the Westerschelde response models to fish and macro-crustacean data from the Oosterschelde

    OpenAIRE

    Hostens, K.

    2003-01-01

    The aim of this study is to test the applicability of the statistical models, which were developed to predict fish and macro-crustacean responses to the environmental conditions in the Westerschelde estuary (Chapter 6). For this, a data set from the Oosterschelde was used. The probability of occurrence and the prediction of abundance of several dermersal fish and macro-crustaceans in reponse to four environmental variables (salinity, temperature, dissolved oxygen concentration and turbidity) ...

  5. White spot syndrome virus infection: Threat to crustacean biodiversity in Vembanad Lake, India

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    Toms C. Joseph

    2015-09-01

    Full Text Available The Vembanad Lake located on the south-west coast of India, an ecological hotspot is the nursing ground of many economically important crustaceans. The prevalence of white spot syndrome virus (WSSV among crustaceans from farmed, estuarine and marine environments surrounding the Vembanad Lake, India was detected using PCR. A total of 308 samples from aquaculture ponds consisting of six species of crustaceans collected from five different farms were tested for the presence of WSSV. Of these, 67% were found to carry the virus. A total of 258 samples of crustaceans from the Cochin backwater system that forms a part of the Vembanad lake viz., Metapenaeus dobsoni, Metapenaeus monoceros, Penaeus monodon and Penaeus indicus were found to contain WSSV in 62% of the samples. Fifteen species of crustaceans caught from the seas off Cochin were also screened for the presence of WSSV. Out of these, twelve species had WSSV incidence levels ranging from 6–23%. WSSV was not detected from three species of deep sea crustaceans tested. The black tiger shrimp, Penaeus monodon had the highest incidence of WSSV among the species screened in farmed, estuarine and marine environments.

  6. Neocaridina denticulata: A Decapod Crustacean Model for Functional Genomics.

    Science.gov (United States)

    Mykles, Donald L; Hui, Jerome H L

    2015-11-01

    A decapod crustacean model is needed for understanding the molecular mechanisms underlying physiological processes, such as reproduction, sex determination, molting and growth, immunity, regeneration, and response to stress. Criteria for selection are: life-history traits, adult size, availability and ease of culture, and genomics and genetic manipulation. Three freshwater species are considered: cherry shrimp, Neocaridina denticulata; red swamp crayfish, Procambarus clarkii; and redclaw crayfish, Cherax quadricarinatus. All three are readily available, reproduce year round, and grow rapidly. The crayfish species require more space for culture than does N. denticulata. The transparent cuticle of cherry shrimp provides for direct assessment of reproductive status, stage of molt, and tissue-specific expression of reporter genes, and facilitates screening of mutations affecting phenotype. Moreover, a preliminary genome of N. denticulata is available and efforts toward complete genome sequencing and transcriptome sequencing have been initiated. Neocaridina denticulata possesses the best combination of traits that make it most suitable as a model for functional genomics. The next step is to obtain the complete genome sequence and to develop molecular technologies for the screening of mutants and for manipulating tissue-specific gene expression. PMID:26002561

  7. A shape-anisotropic reflective polarizer in a stomatopod crustacean

    Science.gov (United States)

    Jordan, Thomas M.; Wilby, David; Chiou, Tsyr-Huei; Feller, Kathryn D.; Caldwell, Roy L.; Cronin, Thomas W.; Roberts, Nicholas W.

    2016-01-01

    Many biophotonic structures have their spectral properties of reflection ‘tuned’ using the (zeroth-order) Bragg criteria for phase constructive interference. This is associated with a periodicity, or distribution of periodicities, parallel to the direction of illumination. The polarization properties of these reflections are, however, typically constrained by the dimensional symmetry and intrinsic dielectric properties of the biological materials. Here we report a linearly polarizing reflector in a stomatopod crustacean that consists of 6–8 layers of hollow, ovoid vesicles with principal axes of ~550 nm, ~250 nm and ~150 nm. The reflection of unpolarized normally incident light is blue/green in colour with maximum reflectance wavelength of 520 nm and a degree of polarization greater than 0.6 over most of the visible spectrum. We demonstrate that the polarizing reflection can be explained by a resonant coupling with the first-order, in-plane, Bragg harmonics. These harmonics are associated with a distribution of periodicities perpendicular to the direction of illumination, and, due to the shape-anisotropy of the vesicles, are different for each linear polarization mode. This control and tuning of the polarization of the reflection using shape-anisotropic hollow scatterers is unlike any optical structure previously described and could provide a new design pathway for polarization-tunability in man-made photonic devices. PMID:26883448

  8. Experimental investigation of crustacean swimming with variation of limb structures

    Science.gov (United States)

    Lai, Hong Kuan; Samaee, Milad; Donnell, Geoffrey; Santhanakrishnan, Arvind; Guy, Robert; Lewis, Timothy

    2015-11-01

    Crustaceans such as crayfish and krill swim by rhythmically paddling a set of four to five limbs (known as swimmerets or pleopods) originating from their abdomen. The limb motion in these animals has been observed to follow tail-to-head metachronal wave pattern with an approximate quarter-period inter-limb phase difference. The goal of this study is to investigate the hydrodynamics of this swimming mechanism as a function of inter-limb phase difference, inclusion of hinges in the limbs, and Reynolds number (Re). 2D PIV measurements were conducted on a scaled robotic model of metachronal paddling, consisting of a rectangular tank fitted with stepper motors coupled to a four-bar linkage that actuated four paddles immersed in water-glycerin fluid medium. The inter-limb phase difference was varied from 0% (synchronous paddling) through 50% across Re range of O(10-1000). Two types of limb models were used, including a simple flat plate and a `split-paddle' structure with two flat plates connected halfway with hinges. The results of the study show that limb models with hinges generated increased horizontal (thrust-producing direction) fluid velocity compared to the simple flat plate paddles, suggesting that asymmetry between power and return strokes is important to augment thrust.

  9. Identification of a divergent environmental DNA sequence clade using the phylogeny of gregarine parasites (Apicomplexa from crustacean hosts.

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    Sonja Rueckert

    Full Text Available BACKGROUND: Environmental SSU rDNA surveys have significantly improved our understanding of microeukaryotic diversity. Many of the sequences acquired using this approach are closely related to lineages previously characterized at both morphological and molecular levels, making interpretation of these data relatively straightforward. Some sequences, by contrast, appear to be phylogenetic orphans and are sometimes inferred to represent "novel lineages" of unknown cellular identity. Consequently, interpretation of environmental DNA surveys of cellular diversity rely on an adequately comprehensive database of DNA sequences derived from identified species. Several major taxa of microeukaryotes, however, are still very poorly represented in these databases, and this is especially true for diverse groups of single-celled parasites, such as gregarine apicomplexans. METHODOLOGY/PRINCIPAL FINDINGS: This study attempts to address this paucity of dna sequence data by characterizing four different gregarine species, isolated from the intestines of crustaceans, at both morphological and molecular levels: Thiriotia pugettiae sp. n. from the graceful kelp crab (Pugettia gracilis, Cephaloidophora cf. communis from two different species of barnacles (Balanus glandula and B. balanus, Heliospora cf. longissima from two different species of freshwater amphipods (Eulimnogammarus verrucosus and E. vittatus, and Heliospora caprellae comb. n. from a skeleton shrimp (Caprella alaskana. SSU rDNA sequences were acquired from isolates of these gregarine species and added to a global apicomplexan alignment containing all major groups of gregarines characterized so far. Molecular phylogenetic analyses of these data demonstrated that all of the gregarines collected from crustacean hosts formed a very strongly supported clade with 48 previously unidentified environmental DNA sequences. CONCLUSIONS/SIGNIFICANCE: This expanded molecular phylogenetic context enabled us to

  10. CHHBP: a newly identified receptor of crustacean hyperglycemic hormone.

    Science.gov (United States)

    Li, Ran; Tian, Jin-Ze; Zhuang, Cui-Heng; Zhang, Yi-Chen; Geng, Xu-Yun; Zhu, Li-Na; Sun, Jin-Sheng

    2016-04-15

    Crustacean hyperglycemic hormone (CHH) is a neurohormone found only in arthropods that plays a pivotal role in the regulation of hemolymph glucose levels, molting and stress responses. Although it was determined that a membrane guanylyl cyclase (GC) acts as the CHH receptor in the Y-organ during ecdysteroidogenesis, the identity of the CHH receptor in the hepatopancreas has not been established. In this study, we identified CHH binding protein (CHHBP), as a potential receptor by screening the annotated unigenes from the transcriptome of ITALIC! Eriocheir sinensis, after removal of the eyestalk. Analysis of the binding affinity between CHH and CHHBP provided direct evidence that CHH interacts with CHHBP in a specific binding mode. Subsequent analysis showed that CHHBP is expressed primarily in the hepatopancreas where it localizes to the cell membrane. In addition, real-time PCR analysis showed that ITALIC! CHHBPtranscript levels gradually increase in the hepatopancreas following eyestalk ablation. RNAi-mediated suppression of ITALIC! CHHBPexpression resulted in decreased glucose levels. Furthermore, the reduction of blood glucose induced by ITALIC! CHHBPRNAi reached the same level as that observed in the eyestalk ablation group, suggesting that CHHBP is involved in glucose metabolism regulated by CHH. In addition, compared with the control group, injection of CHH was unable to rescue the decreased glucose levels in ITALIC! CHHBPRNAi crabs. CHH induced transport of 2-NBDG to the outside of cells, with indispensable assistance from CHHBP. Taken together, these findings suggest that CHHBP acts as one type of the primary signal processor of CHH-mediated regulation of cellular glucose metabolism. PMID:26896539

  11. Extended parental care in crustaceans: an update Cuidado parental extendido en crustáceos: conocimiento actual

    Directory of Open Access Journals (Sweden)

    MARTIN THIEL

    2003-06-01

    increase in dispersal distances of crustaceans with XPC via rafting, surpassing that of crustaceans with pelagic larvae. Since crustaceans with XPC may be particularly susceptible to changing environmental conditions, especially in the terrestrial environment where populations are often small and locally restricted, conservation of biodiversity should focus on these (and other invertebrate species with XPCMuchas especies de crustáceos presentan cuidado parental extendido (XPC, donde individuos juveniles completamente desarrollados son cuidados por los padres. En la presente contribución se revisa el conocimiento actual del XPC, sus consecuencias y además se identifican tópicos importantes para ser investigados en el futuro. Los crustáceos que presentan XPC pueden ser encontrados en ambientes marinos, límnicos y terrestres, pero el XPC es más conspicuo y aparentemente más común en el ambiente terrestre. En todas las especies analizadas, las hembras desarrollan las principales tareas relacionadas con el XPC. Crustáceos que portan sus juveniles en alguna estructura del cuerpo (i.e. marsupio durante el XPC liberan a estos tempranamente, mientras que las especies que habitan refugios pueden albergar a sus crías incluso cuando éstas alcanzan estadios tardíos de desarrollo, o bien, la adultez. Además de proveer un microhabitat adecuado y seguro para las crías, las madres comparten el alimento con, limpian y/o defienden activamente a sus juveniles. Entre los beneficios más importantes del XPC figura el incremento de las tasas de crecimiento y sobrevivencia de los juveniles. El XPC puede producir conflictos entre las crías o entre los padres y sus crías, especialmente durante la etapa tardía del XPC, cuando algunos recursos (alimento y espacio pueden llegar a ser aún más limitantes. De manera similar, debido a la proximidad y frecuente interacción entre padres y crías, epibiontes (e.g., parásitos pueden ser transferidos desde los padres hacia los juveniles

  12. [Diversity and faunal analysis of crustaceans in Potatso National Park, Shangri-La, China].

    Science.gov (United States)

    Shu, Shu-Sen; Chen, Fei-Zhou; Yang, Jun-Xing; Yang, Xiao-Jun; Chen, Xiao-Yong

    2013-06-01

    Potatso National Park was the first national park in mainland China, preceded by the earlier Bitahai Nature Reserve. Located in the northwest of Yunnan and on the southeast of Qinghai-Tibet plateau, Potatso is a typical low latitude and high elevation wetland nature reserve, with large areas of coniferous forest around alpine lakes and both wetland and water area ecosystems. In August, 2011, we undertook a survey of crustaceans in the park, sampling lakes, ponds, streams, and rivers throughout Potatso. We found a total of 29 species (including varieties) belonging to 24 genera and 11 families. Notable discoveries include Parartemiopsis sp, Arctodiaptomus parvispinus and Simocephalus congener, which are the first examples of these species to be recorded in China. Likewise, Gammarus bitaensis is a unique crustacean found only in Potatso National Park and Thermocyclops dumonti and Gammarus paucispinus are both endemic species to northwestern Yunnan. The overall faunal characteristics of crustaceans in the park also revealed several things about Potatso: (1) Cosmopolitan and Palaearctic elements reach 48.27% and 37.93%, clearly showing the Palaearctic element as the dominant fauna; (2) most of the crustacean, such as Arctodiaptomus parvispinus and Gammarus, are typical alpine types, confirming that Potatso has feature typical of alpine and plateau fauna; and (3) the proportion of endemic and rare crustacean species in Potatso National Park is approximately 10%, suggesting that the Potatso National Park in particular and the northwest of Yunnan in general have a unique geological and evolutionary history. PMID:23775996

  13. Surviving environmental stress: the role of betaine aldehyde dehydrogenase in marine crustaceans

    Directory of Open Access Journals (Sweden)

    NA Stephens-Camacho

    2015-02-01

    Full Text Available Betaine aldehyde dehydrogenase (BADH belongs to the aldehyde dehydrogenases (ALDH family, an ancestral group of enzymes responsible for aldehyde detoxification in several organisms. The BADH enzyme catalyzes the irreversible oxidation of betaine aldehyde to glycine betaine (GB an important osmoptrotector and osmoregulator accumulated in response to cellular osmotic stress. The BADH enzymes have been extensively described in terrestrial organisms, but information in marine crustaceans remains scarce. Research on crustacean stress-adaptive capacity to environmental stressors relates GB accumulation in response to salinity variations. Although GB de novo synthesis is confirmed on crustaceans, its metabolic pathways and regulation mechanism are unexplored. In this work, the state of the knowledge of betaine aldehyde dehydrogenase enzymes in marine crustaceans is summarized, as a mechanism to overcome the deleterious effects of changes in temperature, salinity and dissolved oxygen concentration in seawater. The purpose of this review is to provide a more comprehensive overview to set the basis for exploring novel functions and properties of BADHs on the response of crustaceans to environmental stress.

  14. Scale-dependent analysis of an otter-crustacean system in Argentinean Patagonia

    Science.gov (United States)

    Cassini, Marcelo H.; Fasola, Laura; Chehébar, Claudio; MacDonald, David W.

    2009-05-01

    The Southern river otter or ‘huillin’, Lontra provocax, is an endangered species endemic of the Andean Patagonian region of Argentina and Chile. It feeds almost exclusively on the genera of macro-crustacea: Aegla and Sammastacus. The aim of this study was to analyse the role of food availability on the huillin’s distribution using a scale-dependent analysis of crustacean and otter distributions. We compared the distributions of otters and macro-crustaceans along a north-south regional gradient, between river basins of northern Patagonia, in an altitudinal gradient within a river basin, and between habitat types within a lake. We investigated the distribution of otters by sign surveys along lake shores, river banks and marine coasts, and of crustaceans using surveys in the water, undigested remains in mink ( Mustela vison) scats, presence of external skeletons at the waterside and through interviews with local people. Our results show that there were heterogeneities in the distributions of macro-crustaceans at four scales and these were generally reflected in the distributions of freshwater otters. We conclude that the main factor limiting the distributions of L. provocax in freshwater environments is the availability of macro-crustaceans. This paper shows how scale-dependent type analyses of population distribution serves as a method for identifying key environmental factors for species for which the use of long-term demographies is unfeasible.

  15. Anticholinesterase effect of eserine (physostigmine in fish and crustacean species

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    José M. Monserrat

    2001-03-01

    Full Text Available The kinetic characteristic (Km of cholinesterase from the crab Chasmagnathus granulata, the shrimp Farfantepenaeus paulensis and the fish Odontesthes bonaeriensis were compared and correlated with the anticholinesterasic effect of eserine (physostigmine. For the crustaceans, the estimated Km values were about 5-8 times higher than that estimated for the fish (0.04 mM. In the crab and the shrimp, the concentration of eserine which inhibited 50% of cholinesterase activity (IC50 was estimated as 5.33x10-4 and 4.33x10-4 mM, respectively. In both cases, it was significantly higher (P As caraterísticas cinéticas (Km de colinesterases do caranguejo Chasmagnathus granulata, o camarão Farfantepenaeus paulensis e o peixe Odontesthes bonaeriensis foram comparadas e correlacionadas com os efeitos anticolinesterásicos da eserina (fisostigmina. Nos crustáceos, o valores estimados de Km foram aproximadamente 5-8 vezes maiores do que aquele estimado para a espécie de peixe (0.04 mM. No caranguejo e camarão, a concentração de eserina que inibiu 50% da atividade colinesterásica (CI50 foi estimada em 5.33x10-4 e 4.33x10-4 mM, respectivamente. Estes valores foram significativamente maiores (P < 0.05 que aquele estimado para as larvas de peixes (7.43x10-5 mM. Um valor de Km mais elevado poderia refletir uma menor afinidade da colinesterase pelo seu substrato natural, acetilcolina, ou análogos tais como inseticidas carbamatos e fosforados. Se a CI50 para eserina é considerada como um índice da susceptibilidade da enzima a inibição por inseticidas, logo a colinesterase de larvas de peixes poderiam ser uma ferramenta mais útil no monitoramento de inseticidas do que aquelas das espécies de crustáceos.

  16. Using DNA Barcoding and Standardized Sampling to Compare Geographic and Habitat Differentiation of Crustaceans: A Hawaiian Islands Example

    Directory of Open Access Journals (Sweden)

    M. Julian Caley

    2011-09-01

    Full Text Available Recently, the Census of Marine Life has explored methods to assess coral reef diversity by combining standardized sampling (to permit comparison across sites with molecular techniques (to make rapid counts of species possible. To date, this approach has been applied across geographically broad scales (seven sites spanning the Indian, Pacific and Atlantic Oceans, focusing on similar habitats at all sites (10–12 m forereef. Here we examine crustacean spatial diversity patterns for a single atoll, comparing results for four sites (comprising forereef, backreef, and lagoon habitats at French Frigate Shoals (FFS, Northwestern Hawaiian Islands, Hawaii, USA, within the Papahanaumokuakea Marine National Monument. The Bray-Curtis index of similarity across these habitats at FFS was the same or greater than the similarity between similar habitats on Heron Island and Lizard Island in the Great Barrier Reef and much greater than similarity between more widely separated localities in the Indo-Pacific Ocean (e.g., Ningaloo, Moorea, French Polynesia or the Line Islands. These results imply that, at least for shallow reefs, sampling multiple locations versus sampling multiple habitats within a site maximizes the rate at which we can converge on the best global estimate of coral reef biodiversity.

  17. Trophic transfer of differently coated zinc oxide nanoparticles using crustaceans (Daphnia magna) and zebrafish (Danio rerio)

    DEFF Research Database (Denmark)

    Skjolding, Lars Michael; Winther-Nielsen, M.; Baun, Anders

    ecotoxicity of ZnO NP and to our knowledge the bioaccumulation behavior in regards to difference in functionalization of ZnO NP has not been studied previously. In this study, experiments with trophic transfer using crustaceans (Daphnia magna) as food source for zebrafish (Danio rerio) was carried out to test...

  18. Decapod crustaceans from the Neogene of the Caribbean: diversity, distribution and prospectus

    NARCIS (Netherlands)

    Collins, J.S.H.; Portell, R.W.; Donovan, S.K.

    2009-01-01

    The Neogene decapod crustaceans are reviewed from Aruba, Bonaire and Curaçao, Anguilla, Barbados, Carriacou, Costa Rica, Cuba, Florida, Hispaniola (Haiti and Dominican Republic), Jamaica, Mexico, Panama, Puerto Rico, St. Kitts, Tintamare Island, Trinidad and Venezuela. The most widely distributed ta

  19. Zoological detective stories: the case of the facetotectan crustacean life cycle

    OpenAIRE

    Scholtz, Gerhard

    2008-01-01

    The reconstruction of complete animal life cycles is sometimes a considerable problem, even though the knowledge of the full life cycle may have far-reaching evolutionary implications. A new study published in BMC Biology on artificially induced metamorphosis in an enigmatic crustacean group that was only known from larval stages sheds new light on the evolution of parasitism.

  20. PCBs, PCDD/Fs and PBDEs in crustaceans from different French coastal sites

    Energy Technology Data Exchange (ETDEWEB)

    Bodin, N.; Abarnou, A. [IFREMER, Brest (France); Defour, S.; Fraisse, D. [CARSO, Lyon (France)

    2004-09-15

    There is very few information on the presence of persistent organo-halogenated contaminants in crustaceans from the French coast. A previous report pointed out high levels of dioxins in seafood marketed in France, particularly in large crustaceans. However, these data were very limited and the dioxin concentrations were reported on a fat basis. In this paper new data on PCBs, PCDD/Fs and PBDEs in crustaceans will be discussed. Our first objective was to obtain an estimation of the concentration ranges of those contaminants in large crustaceans from the French coast. For that purpose, three areas were selected: the first one in the Bay of Seine, the others along the Brittany coast. According to results obtained within the French marine pollution monitoring programme (RNO), these sites are assumed to represent very opposite situations: on the one hand the coasts of Brittany which are very little contaminated by such man-made contaminants of industrial origin, on the other hand the Bay of Seine where highest PCB levels are currently measured in mussels and other species living close to the Seine Estuary. The second objective was to contribute to a better understanding of the factors acting on the distribution of these contaminants. Our approach is based on a detailed examination and comparison of the contaminant fingerprints in biological tissues according to either the origin of the samples, or the type of species in relation with their trophic position, feeding mode or metabolising capacities.

  1. Integrating Hot and Cool Intelligences: Thinking Broadly about Broad Abilities

    Directory of Open Access Journals (Sweden)

    W. Joel Schneider

    2016-01-01

    Full Text Available Although results from factor-analytic studies of the broad, second-stratum abilities of human intelligence have been fairly consistent for decades, the list of broad abilities is far from complete, much less understood. We propose criteria by which the list of broad abilities could be amended and envision alternatives for how our understanding of the hot intelligences (abilities involving emotionally-salient information and cool intelligences (abilities involving perceptual processing and logical reasoning might be integrated into a coherent theoretical framework.

  2. Infertility in a marine crustacean: have we been ignoring pollution impacts on male invertebrates?

    Science.gov (United States)

    Yang, Gongda; Kille, Peter; Ford, Alex T

    2008-06-01

    Invertebrate infertility has been under-explored as a potential ecological issue or biomarker of stress within ecotoxicology. To date, the majority of studies focussing on contaminant induced infertility have centred on vertebrate groups. This study aimed to address the question whether industrial pollution has the ability to influence the sperm counts and testicular morphology of male amphipod, Echinogammarus marinus (Leach). In addition, the sperm counts of normal and intersex specimens were compared to assess the potential impact of a crustacean with a disrupted endocrine system. Specimens of E. marinus were collected at one industrially impacted (Inverkeithing) and two reference (Thurso and Loch Fleet) sites along the north and eastern coasts of Scotland. Significantly higher sperm counts ( approximately 20%) were observed from normal males collected from reference sites compared to the industrially impacted site. Higher proportions (30%) of intersex specimens were observed at the industrially impacted site compared to 17 and 6% male intersexuality observed at Thurso and Loch Fleet, respectively. Intersex male specimens from Thurso had lower mean sperm counts ( approximately 15%) than normal male specimens, however, this result was not significant (P=0.089). No significant differences in sperm counts were observed between normal and intersex males at Inverkeithing. Our results indicate that industrial pollution does have the potential to affect the sperm counts of male crustaceans. Whether the quality of sperm in Crustacea from contaminated sites is also compromised or whether this is an endocrine mediated effect is yet to be confirmed. To date, many of the studies of endocrine disruption in crustaceans have, surprisingly, focussed on female fecundity parameters, growth and moulting despite many of the vertebrate studies initially focussing on the male gender. Whether this could be an ecological issue needs to be addressed through further field and laboratory

  3. Transboundary movement of shrimp viruses in crustaceans and their products: a special risk?

    Science.gov (United States)

    Jones, Brian

    2012-06-01

    Shrimp and shrimp products form the most valuable internationally traded fisheries commodity, and the volumes are huge, estimated to be about 3.6 million tonnes. However, despite the existence under the General Agreement on Tariffs and Trade, of the Sanitary and Phytosanitary Measures (SPS Agreement) and the activities of the World Organisation for Animal Health (OIE), viral shrimp epizootics have spread and continue to spread, affecting world production. Though most attention has focussed on the movement of live shrimp product, the spread of new and emerging diseases through other crustaceans and their nonviable products is of increasing concern. The risks associated with the unrestricted movement of nonviable product will be outlined and measures that can be taken to mitigate the risk are discussed. Ultimately, for crustacean diseases, the paradigm under which the OIE has operated for the past 80 years needs to change. PMID:22434004

  4. Selfing in a malacostracan crustacean: why a tanaidacean but not decapods

    Science.gov (United States)

    Kakui, Keiichi; Hiruta, Chizue

    2013-09-01

    The crustacean class Malacostraca, with over 22,000 species, includes commercially important members, such as crabs, shrimps, and lobsters. A few simultaneous hermaphrodites are known in this group, but self-fertilization was unknown. Here we show, through microscopy and breeding experiments, that the simultaneously hermaphroditic malacostracan Apseudes sp. (order Tanaidacea) can self-fertilize; individuals reared in isolation become hermaphroditic via a male-like phase and produce eggs that develop into fertile adults. Although selfing occurs in crustaceans like the Branchiopoda, in which simultaneous hermaphrodites have the sex ducts united, in decapods the separation of gonadal ducts and gonopores, specialized mating organs, and complex mating behavior appear to have constrained the evolution of selfing. In contrast, in most tanaidaceans, sperm is released externally by a male and reaches the eggs in the female brood pouch, where fertilization occurs. This mode of fertilization permitted Apseudes sp. to achieve selfing without large modifications in morphology or behavior.

  5. Effects of temperature and salinity on the development of the amphipod crustacean Eogammarus sinensis

    Science.gov (United States)

    Xue, Suyan; Fang, Jianguang; Zhang, Jihong; Jiang, Zengjie; Mao, Yuze; Zhao, Fazhen

    2013-09-01

    The amphipod crustacean Eogammarus sinensis has useful features that make it suitable for use in the aquaculture of fish and large decapod crustaceans. In this study, we investigated the effects of temperature and salinity on the development, fecundity, survival, and growth rate of E. sinensis. The results show that temperature significantly affected E. sinensis development, but salinity. As temperature increased, the duration of E. sinensis embryonic development decreased. Fecundity was affected significantly by temperature and the combination of temperature and salinity, but by salinity alone. In addition, high temperatures accelerated E. sinensis juvenile growth rates, whereas high salinity reduced it. Therefore, our data suggest that E. sinensis tolerates a wide range of salinities and that temperature has more significant effects than salinity on the embryonic development, fecundity, and growth of E. sinensis. Our results shall be useful for mass production of this species for use in aquaculture.

  6. Vertical distribution, composition, and abundance of crustacean zooplankton in the offshore waters of Lake Michigan

    International Nuclear Information System (INIS)

    During 1975, zooplankton samples were collected on eight cruises (April to November) in the southern basin of Lake Michigan. Four stations in the northern basin were also sampled in January during a cruise aboard the USCGC Westwind. One of the goals of this study was to quantitatively estimate the standing crop of herbivorous crustacean zooplankton in units that would represent their functional roles as consumers of phytoplankton

  7. Aspects of the ecology of the crustacean zooplankton in the Sanyati Basin, Lake Kariba

    OpenAIRE

    Marshall, B.E.

    1980-01-01

    Investigations on the zooplankton in Lake Kariba were carried out as part of a broader programme investigating components of the sardine, Limnothrissa miodon, food chain and factors affecting their productivity. This report deals mainly with the crustacean zooplankton, Bosmina longirostris and Mesocyclops leuckarti, which are the most important species in the sardine's diet. Factors which influence the number and distribution of the zooplankton are discussed. The relationship between the zoop...

  8. Multidisciplinary study of trophic diversity and functional role of amphipod crustaceans associated to Posidonia oceanica meadows

    OpenAIRE

    Michel, Loïc

    2011-01-01

    Posidonia oceanica is the most abundant seagrass of the Mediterranean Sea. It can cover extensive areas with monospecific formations, called meadows. These meadows, whose extent is estimated to about 40,000 km2, are critical features of the Mediterranean coastal zones. Moreover, they shelter important biomass and biodiversity of vagile invertebrates. Among these invertebrates, amphipod crustaceans are, alongside gastropod mollusks and polychaete annelids, one of the dominant groups. Amphip...

  9. Genotyping of white spot syndrome virus on wild and farm crustaceans from Sonora, Mexico

    OpenAIRE

    González-Galaviz José Reyes; Rodriguez-Anaya Libia Zulema; Molina-Garza Zinnia Judith; Ibarra-Gámez José Cuauhtémoc; Galaviz-Silva Lucio

    2013-01-01

    White spot syndrome is a viral disease affecting wild and farm crustaceans that serve as reservoirs. Previous reports have demonstrated high genomic variation in WSS viruses (WSSV) isolated from distinct geographical regions. In this study, we collected wild shrimps (Litopenaeus stylirostris), crabs (Callinectes arcuatus) and farmed shrimp (L. vannamei) in Sonora, Mexico, between 2008 and 2010. DNA was extracted, and the variable regions and transposase genes were subjected to PCR and s...

  10. Stranding and mortality of pelagic crustaceans in the western Indian Ocean

    OpenAIRE

    Romanov, E.V.; Potier, Michel; Anderson, R.C.; Quod, J. P.; Ménard, Frédéric; Sattar, S.A.; Hogarth, P.

    2015-01-01

    Recent observations of unusual mass stranding and mortality of two Indian Ocean crustacean species, the swimming crab Charybdis smithii and the mantis shrimp Natosquilla investigatoris, are documented and analysed. Strandings of C. smithii were observed for the first time in the equatorial Indian Ocean, the main area of its pelagic distribution. Strandings of mantis shrimps are reported from throughout the western Indian Ocean; occurrences of mass stranding in the Maldives Archipelago mark an...

  11. Decapod crustaceans from the Neogene of the Caribbean: diversity, distribution and prospectus

    OpenAIRE

    Collins, J.S.H.; Portell, R.W.; Donovan, S.K.

    2009-01-01

    The Neogene decapod crustaceans are reviewed from Aruba, Bonaire and Curaçao, Anguilla, Barbados, Carriacou, Costa Rica, Cuba, Florida, Hispaniola (Haiti and Dominican Republic), Jamaica, Mexico, Panama, Puerto Rico, St. Kitts, Tintamare Island, Trinidad and Venezuela. The most widely distributed taxa, both stratigraphically and geographically, are callianassids and Calappa (both with easily identifiable dactyli), and portunids. The latter include eleven genera in the study area; of these, Ca...

  12. Use of brine shrimp, Artemia spp., in larval crustacean nutrition: a review

    OpenAIRE

    Sorgeloos, P.; Coutteau, P.; Dhert, Ph.; Merchie, G.; Lavens, P.

    1998-01-01

    Because of convenience in production and their suitable biochemical composition, brine shrimp Artemia spp. nauplii have been adopted as a standard diet in the commercial larviculture of several crustacean species. The nutritional value of Artemia, however, is not constant, but varies both geographically and temporally. During the past decade both the causes of Artemia nutritional variability and methods to improve poor-quality Artemia have been identified. Enriching Artemia spp. with emulsifi...

  13. Variation in egg and larval quality in various fish and crustacean species

    OpenAIRE

    Lavens, P.; Sorgeloos, P

    1991-01-01

    It is generally accepted, that a major constraint in the further development of marine fish and crustacean aquaculture, is the variable quality of eggs and larvae used for the hatchery-production of fry. Nonetheless, valid criteria to evaluate optimal egg quality have not been identified yet. Instead, particular indicators, are used, e.g. the fertilization and hatching rate, overall culture success during the first rearing period, etc., but these are not totally objective because hatchery-spe...

  14. Molecular identification of a Drosophila G protein-coupled receptor specific for crustacean cardioactive peptide

    DEFF Research Database (Denmark)

    Cazzamali, Giuseppe; Hauser, Frank; Kobberup, Sune;

    2003-01-01

    The Drosophila Genome Project website (www.flybase.org) contains the sequence of an annotated gene (CG6111) expected to code for a G protein-coupled receptor. We have cloned this receptor and found that its gene was not correctly predicted, because an annotated neighbouring gene (CG14547) was als...... head. Furthermore, we identified a gene sequence in the genomic database from the malaria mosquito Anopheles gambiae that very likely codes for a crustacean cardioactive peptide receptor....

  15. Prevalence of Colacium vesiculosum (Colaciales: Euglenophyceae on planktonic crustaceans in a subtropical shallow lake of Argentina

    Directory of Open Access Journals (Sweden)

    Yolanda Zalocar

    2011-09-01

    Full Text Available Colacium vesiculosum (Euglenophyceae is an epibiont common on planktonic microcrustaceans of continental waters. The interaction between epibionts and substrate organisms is not very well known, particularly in subtropical environments of South America. In the present work, we analyzed the prevalence, density, biomass and attachment sites of C. vesiculosum on planktonic microcrustaceans from Paiva Lake, a subtropical lake of Argentina. With the aim to evaluate whether epibionts affect the filtering rates of Notodiaptomus spiniger, the dominant planktonic crustacean, we carried out bioassays using phytoplankton <53µm. Crustaceans were sampled using a PVC tube (1.2m long and 10cm in diameter, filtering 50L of water through a 53µm-mesh. Microcrustaceans were counted in Bogorov chambers under a stereoscopic microscope. The infested organisms were separated and observed with a photonic microscope to determine density and biovolume of epibionts, by analyzing their distribution on the exoskeleton. The prevalence of C. vesiculosum was higher in adult crustaceans than in their larvae and juveniles. The most infested group was that of calanoid copepods, related to their high density. The attachment sites on the exoskeleton were found to be the portions of the body which have a higher probability of encounter with epibionts during locomotion and feeding, i.e., antennae and thoracic legs in copepods, and thoracic legs and postabdomen in cladocerans. The similar values found in the filtering rate of infested and uninfested individuals of N. spiniger and the constant prevalence (<40% of epibiont algae, suggest that C. vesiculosum does not condition the life of planktonic crustaceans of Paiva Lake. Rev. Biol. Trop. 59 (3: 1295-1306. Epub 2011 September 01.

  16. 3D elemental imaging of the crustacean Ceriodaphnia by means of SR confocal micro-XRF

    OpenAIRE

    De Samber, Björn; Evens, Roel; Boone, Matthieu; De Schamphelaere, Karel; Van Hoorebeke, Luc; Janssen, Colin; Falkenberg, Gerald; Appel, Karen; Vincze, Laszlo

    2011-01-01

    Daphnia is a freshwater crustacean (0.2-5 mm height) used for investigating the toxic effects of toxins (e.g. metals) on an ecosystem. Synchrotron radiation based micro X-ray fluorescence (SR micro-XRF) allows the investigation of the trace level metal distribution within these organisms in an essentially non-destructive manner. Several two-dimensional (2D), computed tomography (CT) and confocal micro-XRF experiments under conventional and cryogenic environments have been performed on Daphnia...

  17. Evaluation of Paracentrotus lividus (Lamarck, 1816) exotrophic larvae as live feed for marine decapod crustacean larvae

    OpenAIRE

    Repolho, Tiago Filipe Baptista da Rosa, 1974-

    2012-01-01

    Tese de doutoramento, Biologia (Biologia Marinha e Aquacultura), Universidade de Lisboa, Faculdade de Ciências, 2012 In the present study, we have evaluated 4‐arm exotrophic larvae of sea urchin Paracentrotus lividus (Echinodermata: Echinoidea) as live feed in marine decapod crustacean larviculture, in comparison to Artemia spp. naupliar stages, a commonly used live prey in marine hatcheries. We therefore investigated several key parameters to assess the potential of P. lividus plutei as l...

  18. Organochlorinated contaminants in decapod crustaceans from the coasts of Brittany and Normandy (France)

    OpenAIRE

    Bodin, Nathalie; Abarnou, Alain; Le Guellec, Anne-marie; Loizeau, Veronique; Philippon, Xavier

    2007-01-01

    The contamination and distribution of organ ochlorinated compounds were considered in three crustacean species (edible crab, Cancer pagurus; spider crab, Maja brachydactyla; velvet swimming crab, Necora puber) from five sites along the coasts of Brittany and Normandy (Western and North-Western France). PCBs (16 single congeners), pp'-DDE and HCB were measured in hepatopancreas, gonads and muscle: in all, 175 samples were analysed. The spider crab was the only species found in the five samplin...

  19. Crustacean zooplankton species richness in Chilean lakes and ponds (23°-51°S)

    OpenAIRE

    Patricio De los Ríos-Escalante

    2013-01-01

    Chilean inland-water ecosystems are characterized by their low species-level biodiversity. This study analyses available data on surface area, maximum depth, conductivity, chlorophyll-α concentration, and zooplankton crustacean species number in lakes and ponds between 23° and 51°S. The study uses multiple regression analysis to identify the potential factors affecting the species number. The partial correlation analysis indicated a direct significant correlation between chlorophyll-α concent...

  20. The Evolution of Social Monogamy and Biparental Care in Stomatopod Crustaceans

    OpenAIRE

    Wright, Mary Louisa

    2013-01-01

    ABSTRACTThe Evolution of Social Monogamy and Biparental Care in Stomatopod CrustaceansBy Mary Louisa WrightDoctor of Philosophy in Integrative BiologyUniversity of California, BerkeleyProfessor Roy L. Caldwell, Chair Although social monogamy and biparental care have been extensively studied in birds, mammals, and fish, the evolutionary origins and maintenance of these phenomena are not well-understood, particularly in invertebrate taxa. The evolution of social monogamy is of interest because ...

  1. Algal Diet of Small-Bodied Crustacean Zooplankton in a Cyanobacteria-Dominated Eutrophic Lake

    Science.gov (United States)

    Tõnno, Ilmar; Agasild, Helen; Kõiv, Toomas; Freiberg, Rene; Nõges, Peeter; Nõges, Tiina

    2016-01-01

    Small-bodied cladocerans and cyclopoid copepods are becoming increasingly dominant over large crustacean zooplankton in eutrophic waters where they often coexist with cyanobacterial blooms. However, relatively little is known about their algal diet preferences. We studied grazing selectivity of small crustaceans (the cyclopoid copepods Mesocyclops leuckarti, Thermocyclops oithonoides, Cyclops kolensis, and the cladocerans Daphnia cucullata, Chydorus sphaericus, Bosmina spp.) by liquid chromatographic analyses of phytoplankton marker pigments in the shallow, highly eutrophic Lake Võrtsjärv (Estonia) during a seasonal cycle. Copepods (mainly C. kolensis) preferably consumed cryptophytes (identified by the marker pigment alloxanthin in gut contents) during colder periods, while they preferred small non-filamentous diatoms and green algae (identified mainly by diatoxanthin and lutein, respectively) from May to September. All studied cladoceran species showed highest selectivity towards colonial cyanobacteria (identified by canthaxanthin). For small C. sphaericus, commonly occuring in the pelagic zone of eutrophic lakes, colonial cyanobacteria can be their major food source, supporting their coexistence with cyanobacterial blooms. Pigments characteristic of filamentous cyanobacteria and diatoms (zeaxanthin and fucoxanthin, respectively), algae dominating in Võrtsjärv, were also found in the grazers’ diet but were generally avoided by the crustaceans commonly dominating the zooplankton assemblage. Together these results suggest that the co-occurring small-bodied cyclopoid and cladoceran species have markedly different algal diets and that the cladocera represent the main trophic link transferring cyanobacterial carbon to the food web in a highly eutrophic lake. PMID:27124652

  2. Conservation Value

    OpenAIRE

    Tisdell, Clement A.

    2010-01-01

    This paper outlines the significance of the concept of conservation value and discusses ways in which it is determined paying attention to views stemming from utilitarian ethics and from deontological ethics. The importance of user costs in relation to economic decisions about the conservation and use of natural resources is emphasised. Particular attention is given to competing views about the importance of conserving natural resources in order to achieve economic sustainability. This then l...

  3. Broad Diphotons from Narrow States

    CERN Document Server

    An, Haipeng; Zhang, Yue

    2015-01-01

    ATLAS and CMS have each reported a modest diphoton excess consistent with the decay of a broad resonance at ~ 750 GeV. We show how this signal can arise in a weakly coupled theory comprised solely of narrow width particles. In particular, if the decaying particle is produced off-shell, then the associated diphoton resonance will have a broad, adjustable width. We present simplified models which explain the diphoton excess through the three-body decay of a scalar or fermion. Our minimal ultraviolet completion is a weakly coupled and renormalizable theory of a singlet scalar plus a heavy vector-like quark and lepton. The smoking gun of this mechanism is an asymmetric diphoton peak recoiling against missing transverse energy, jets, or leptons.

  4. Cochlear microphonic broad tuning curves

    Science.gov (United States)

    Ayat, Mohammad; Teal, Paul D.; Searchfield, Grant D.; Razali, Najwani

    2015-12-01

    It is known that the cochlear microphonic voltage exhibits much broader tuning than does the basilar membrane motion. The most commonly used explanation for this is that when an electrode is inserted at a particular point inside the scala media, the microphonic potentials of neighbouring hair cells have different phases, leading to cancelation at the electrodes location. In situ recording of functioning outer hair cells (OHCs) for investigating this hypothesis is exceptionally difficult. Therefore, to investigate the discrepancy between the tuning curves of the basilar membrane and those of the cochlear microphonic, and the effect of phase cancellation of adjacent hair cells on the broadness of the cochlear microphonic tuning curves, we use an electromechanical model of the cochlea to devise an experiment. We explore the effect of adjacent hair cells (i.e., longitudinal phase cancellation) on the broadness of the cochlear microphonic tuning curves in different locations. The results of the experiment indicate that active longitudinal coupling (i.e., coupling with active adjacent outer hair cells) only slightly changes the broadness of the CM tuning curves. The results also demonstrate that there is a π phase difference between the potentials produced by the hair bundle and the soma near the place associated with the characteristic frequency based on place-frequency maps (i.e., the best place). We suggest that the transversal phase cancellation (caused by the phase difference between the hair bundle and the soma) plays a far more important role than longitudinal phase cancellation in the broadness of the cochlear microphonic tuning curves. Moreover, by increasing the modelled longitudinal resistance resulting the cochlear microphonic curves exhibiting sharper tuning. The results of the simulations suggest that the passive network of the organ of Corti determines the phase difference between the hair bundle and soma, and hence determines the sharpness of the

  5. Creative Conservation Communication

    Science.gov (United States)

    Houston, Jason

    2015-04-01

    I am a fellow with the International League of Conservation photographers (iLCP) and have been focused on photographing conservation dynamics at the intersection of social and environmental issues for a decade. Subjects have included traditional concerns such as deforestation, water conservation, endangered species, and fisheries. However, I rarely make photographs of the traditional nature, wildlife, landscapes, or environmental atrocities that most people think of when they think about environmentalism. Instead, I photograph people and how they live on the planet, as I believe passionately that without also considering social and cultural concerns, we will not be able to effectively and sustainably do conservation work or achieve positive environmental change. My presentation will share recent photography projects on forest conservation in Indonesian Borneo and fisheries management in Central America where I used a 'stakeholder profile-based' process to broadly survey the complexity of the issues while also making personal connections for these projects' diverse audiences. Through these case studies I will explore the opportunities and challenges of combining the authenticity, accuracy, and scientific validity of journalistic and documentary work with the emotional impact of the conventions of art and storytelling.

  6. Apolipocrustacein, formerly vitellogenin, is the major egg yolk precursor protein in decapod crustaceans and is homologous to insect apolipophorin II/I and vertebrate apolipoprotein B

    Directory of Open Access Journals (Sweden)

    Lubzens Esther

    2007-01-01

    Full Text Available Abstract Background In animals, the biogenesis of some lipoprotein classes requires members of the ancient large lipid transfer protein (LLTP superfamily, including the cytosolic large subunit of microsomal triglyceride transfer protein (MTP, vertebrate apolipoprotein B (apoB, vitellogenin (Vtg, and insect apolipophorin II/I precursor (apoLp-II/I. In most oviparous species, Vtg, a large glycolipoprotein, is the main egg yolk precursor protein. Results This report clarifies the phylogenetic relationships of LLTP superfamily members and classifies them into three families and their related subfamilies. This means that the generic term Vtg is no longer a functional term, but is rather based on phylogenetic/structural criteria. In addition, we determined that the main egg yolk precursor protein of decapod crustaceans show an overall greater sequence similarity with apoLp-II/I than other LLTP, including Vtgs. This close association is supported by the phylogenetic analysis, i.e. neighbor-joining, maximum likelihood and Bayesian inference methods, of conserved sequence motifs and the presence of three common conserved domains: an N-terminal large lipid transfer module marker for LLTP, a DUF1081 domain of unknown function in their central region exclusively shared with apoLp-II/I and apoB, and a von Willebrand-factor type D domain at their C-terminal end. Additionally, they share a conserved functional subtilisin-like endoprotease cleavage site with apoLp-II/I, in a similar location. Conclusion The structural and phylogenetic data presented indicate that the major egg yolk precursor protein of decapod crustaceans is surprisingly closely related to insect apoLp-II/I and vertebrate apoB and should be known as apolipocrustacein (apoCr rather than Vtg. These LLTP may arise from an ancient duplication event leading to paralogs of Vtg sequences. The presence of LLTP homologs in one genome may facilitate redundancy, e.g. involvement in lipid metabolism and as

  7. Crustaceans from a tropical estuarine sand-mud flat, Pacific, Costa Rica, (1984-1988) revisited

    OpenAIRE

    José A. Vargas-Zamora; Jeffrey A. Sibaja-Cordero; Rita Vargas-Castillo

    2012-01-01

    The availability of data sets for time periods of more than a year is scarce for tropical environments. Advances in hardware and software speed-up the re-analysis of old data sets and facilitates the description of population oscillations. Using recent taxonomic literature and software we have updated and re-analized the information on crustacean diversity and population fluctuations from a set of cores collected at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Pacific coast of Cos...

  8. Barremian decapod crustaceans from Serre de Bleyton (Drôme, SE France)

    Science.gov (United States)

    Hyžný, Matúš; Kroh, Andreas

    2015-01-01

    Based on mostly small-sized isolated cheliped fingers, a new decapod crustacean assemblage is described from the Barremian of Serre de Bleyton (Drôme, SE France). The assemblage is composed mostly of representatives of the crab family Dynomenidae. In addition, remains of astacidean lobsters, axiidean shrimps, paguroid hermit crabs and brachyurous crabs of the families Necrocarcinidae and ?Cenomanocarcinidae occur in low numbers. Graptocarcinus moosleitneri (Dynomenidae) and ?Paranecrocarcinus schloegli (Necrocarcinidae) are introduced as new species. They both exhibit presence of multi-setal pores on dactyli that are interpreted as parts of a sieving mechanism used in feeding. The stratigraphic range of Graptocarcinus is extended herein to the Barremian. PMID:26097276

  9. Seasonal structure of the fish and crustacean community of the Zeeschelde estuary

    OpenAIRE

    J. Maes

    2000-01-01

    Fish and crustaceans were sampled for 1 year in the upper reaches of a temperate estuary characterized by high turbidity and a tidal range of up to 5 m. Samples were taken in the cooling-water circuit of the Doel Nuclear Power station (Zeeschelde, Belgium). Between July 1994 and June 1995, 55 fish species, two shrimp species and four crab species were recorded. The fish community was composed of 36 marine species, 16 freshwater species and three diadromous species. Shrimps, Gobiidae and Clupe...

  10. Seasonal patterns in the fish and crustacean community of a turbid temperate estuary (Zeeschelde Estuary, Belgium)

    OpenAIRE

    J. Maes; Taillieu, A.; Damme, P.A. van; Cottenie, K.; Ollevier, F.P.

    1998-01-01

    Fish and crustaceans were sampled for 1 year in the upper reaches of a temperate estuary characterized by high turbidity and a tidal range of up to 5 m. Samples were taken in the cooling-water circuit of the Doel Nuclear Power station (Zeeschelde, Belgium). Between July 1994 and June 1995, 55 fish species, two shrimp species and four crab species were recorded. The fish community was composed of 36 marine species, 16 freshwater species and three diadromous species. Shrimps, Gobiidae and Clupe...

  11. Detrimental effect of CO2-driven seawater acidification on a crustacean brine shrimp, Artemia sinica.

    Science.gov (United States)

    Zheng, Chao-qun; Jeswin, Joseph; Shen, Kai-li; Lablche, Meghan; Wang, Ke-jian; Liu, Hai-peng

    2015-03-01

    The effects of the decline in ocean pH, termed as ocean acidification due to the elevated carbon dioxide in the atmosphere, on calcifying organisms such as marine crustacean are unclear. To understand the possible effects of ocean acidification on the physiological responses of a marine model crustacean brine shrimp, Artemia sinica, three groups of the cysts or animals were raised at different pH levels (8.2 as control; 7.8 and 7.6 as acidification stress according to the predictions for the end of this century and next century accordingly) for 24 h or two weeks, respectively, followed by examination of their hatching success, morphological appearance such as deformity and microstructure of animal body, growth (i.e. body length), survival rate, expression of selected genes (involved in development, immunity and cellular activity etc), and biological activity of several key enzymes (participated in antioxidant responses and physiological reactions etc). Our results clearly demonstrated that the cysts hatching rate, growth at late stage of acidification stress, and animal survival rate of brine shrimp were all reduced due to lower pH level (7.6 & 7.8) on comparison to the control group (pH 8.2), but no obvious change in deformity or microstructure of brine shrimp was present under these acidification stress by microscopy observation and section analysis. In addition, the animals subjected to a lower pH level of seawater underwent changes on their gene expressions, including Spätzle, MyD88, Notch, Gram-negative bacteria binding protein, prophenoloxidase, Apoptosis inhibitor 5, Trachealess, Caveolin-1 and Cyclin K. Meanwhile, several key enzyme activities, including superoxide dismutase, catalase, peroxidase, alkaline phosphatase and acid phosphatase, were also affected by acidified seawater stress. Taken together, our findings supports the idea that CO2-driven seawater acidification indeed has a detrimental effect, in case of hatching success, growth and survival, on

  12. Experimental mineralization of crustacean eggs leads to surprising tissue conservation: new implications for the fossilization of Precambrian-Cambrian embryos

    Directory of Open Access Journals (Sweden)

    D. Hippler

    2011-12-01

    Full Text Available Phosphatized globular microfossils from the Ediacaran and Lower Cambrian of South China represent an impressive record of early animal evolution and development, however their affinity based on putative embryonic metazoan, bacterial and inorganic features is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are therefore crucial for a reliable interpretation of their phylogenetic position. Taphonomic experiments on eggs of the marbled crayfish indicate a close link between early mineralization and rapid anaerobic decay of the endochorional envelope, producing different preservational stages of degradation resembling the various decay stages observed in the fossil record. Stabilization of the spherical morphology was achieved by pre-heating of the eggs. Complete surface mineralization occurred under reduced conditions within one to two weeks, with fine-grained brushite (CaHPO4·2H2O over calcite as the dominating mineral phase. Although the endochorional envelope was not preserved, experiments resulted in exceptional preservation of the embryonic tissue at the cellular level. Thus our findings suggest that the mechanisms of decay, preservation of surface structures, and mineral replacement in the experiment and during fossilization of Cambrian embryos were likely operating at a similar rationale.

  13. Experimental mineralization of crustacean eggs leads to surprising tissue conservation: new implications for the fossilization of Precambrian-Cambrian embryos

    Science.gov (United States)

    Hippler, D.; Hu, N.; Steiner, M.; Scholtz, G.; Franz, G.

    2011-12-01

    Phosphatized globular microfossils from the Ediacaran and Lower Cambrian of South China represent an impressive record of early animal evolution and development, however their affinity based on putative embryonic metazoan, bacterial and inorganic features is strongly debated. Understanding key processes and conditions that cause exceptional egg and embryo preservation and fossilization are therefore crucial for a reliable interpretation of their phylogenetic position. Taphonomic experiments on eggs of the marbled crayfish indicate a close link between early mineralization and rapid anaerobic decay of the endochorional envelope, producing different preservational stages of degradation resembling the various decay stages observed in the fossil record. Stabilization of the spherical morphology was achieved by pre-heating of the eggs. Complete surface mineralization occurred under reduced conditions within one to two weeks, with fine-grained brushite (CaHPO4·2H2O) over calcite as the dominating mineral phase. Although the endochorional envelope was not preserved, experiments resulted in exceptional preservation of the embryonic tissue at the cellular level. Thus our findings suggest that the mechanisms of decay, preservation of surface structures, and mineral replacement in the experiment and during fossilization of Cambrian embryos were likely operating at a similar rationale.

  14. Reshaping conservation

    DEFF Research Database (Denmark)

    Funder, Mikkel; Danielsen, Finn; Ngaga, Yonika;

    2013-01-01

    members strengthen the monitoring practices to their advantage, and to some extent move them beyond the reach of government agencies and conservation and development practitioners. This has led to outcomes that are of greater social and strategic value to communities than the original 'planned' benefits......, although the monitoring scheme has also to some extent become dominated by local 'conservation elites' who negotiate the terrain between the state and other community members. Our findings suggest that we need to move beyond simplistic assumptions of community strategies and incentives in participatory...... conservation and allow for more adaptive and politically explicit governance spaces in protected area management....

  15. Ghost imaging with broad distance

    Institute of Scientific and Technical Information of China (English)

    段德洋; 张路; 杜少将; 夏云杰

    2015-01-01

    We present a scheme that is able to achieve the ghost imaging with broad distance. The physical nature of our scheme is that the different wavelength beams are separated in free space by an optical media according to the slow light or dispersion principle. Meanwhile, the equality of the optical distance of the two light arms is not violated. The photon correlation is achieved by the rotating ground glass plate (RGGP) and spatial light modulator (SLM), respectively. Our work shows that a monochromic ghost image can be obtained in the case of RGGP. More importantly, the position (or distance) of the object can be ascertained by the color of the image. Thus, the imaging and ranging processes are combined as one process for the first time to the best of our knowledge. In the case of SLM, we can obtain a colored image regardless of where the object is.

  16. Unconventional Approach for Demineralization of Deproteinized Crustacean Shells for Chitin Production

    Directory of Open Access Journals (Sweden)

    N. S. Mahmoud

    2007-01-01

    Full Text Available Chitin is a versatile environmentally friendly modern material. It has a wide range of applications in areas such as water treatment, pulp and paper, biomedical devices and therapies, cosmetics, membrane technology and biotechnology and food applications. Crustacean waste is the most important chitin source for commercial use. Demineralization is an important step in the chitin purification process from crustacean waste. The conventional method of demineralization includes the use of strong acid (commonly HCl that harms the physiochemical properties of chitin, results in a harmful effluent wastewater and increases the cost of chitin purification process. The current study proposes the use of organic acids (lactic and acetic produced by cheese whey fermentation to demineralize microbially deproteinized shrimp shells. The effects of acid type, demineralization condition, retention time and shells to acid ratio were investigated. The study showed that the effectiveness of using lactic and/or acetic acids for demineralization of shrimp shells was comparable to that of using hydrochloric acid. Using organic acids for demineralization is a promising concept, since organic acids are less harmful to the environment, can preserve the characteristics of the purified chitin and can be produced from low cost biomass such as cheese whey. In addition, the resulted organic salts from the demineralization process can be used as a food preservative and/or an environmentally friendly de-icing/anti-icing agents.

  17. Insights into ecological and reproductive aspects of two cryptogenic peracarid crustaceans of the Argentinian coast

    Directory of Open Access Journals (Sweden)

    Anna Fricke

    2015-09-01

    Full Text Available AbstractPeracarid crustaceans belong to the most important agglomerating macrofauna in sedimentary habitats. The amphipod Monocorophium insidiosumCRAWFORD, 1937 and the tanaid Tanais dulongii AUDOUIN, 1926 are listed as invasive species. In the present study, we investigated the ecology of M. insidiosum and T. aff. dulongii from the Argentinian coast. Both crustaceans were breeding under laboratory conditions to study their fecundity and growth. Additionally their behavior and potential interspecific relations have been investigated in four different laboratory experiments. We evaluated tube building capabilities (experiment 1, and tested gender specific responses of M. insdiosum to the presence of empty (experiments 2 and 3, and inhabited T. aff. dulongii tubes (experiment 4. Our results showed high fecundity (three generations within four weeks and growth rates (duplication of body lengths in two weeks for M. insidiosum. Two tube construction strategies were distinguished: a tube changing behavior for the amphipod M. insidiosum, showing greater construction activity for females, and tube keeping behavior for T. aff. dulongii. Overall, tanaid tubes were frequently claimed by M. insidiosum, demonstrating a close interspecific relationship and resulting in decreased sediment aggregating activity. In the light of our observations it may be affirmed that these invasive species are probably frequently distributed along the Patagonian Atlantic coast and will still spread in future.

  18. Ghost imaging with broad distance

    Science.gov (United States)

    Duan, De-Yang; Zhang, Lu; Du, Shao-Jiang; Xia, Yun-Jie

    2015-10-01

    We present a scheme that is able to achieve the ghost imaging with broad distance. The physical nature of our scheme is that the different wavelength beams are separated in free space by an optical media according to the slow light or dispersion principle. Meanwhile, the equality of the optical distance of the two light arms is not violated. The photon correlation is achieved by the rotating ground glass plate (RGGP) and spatial light modulator (SLM), respectively. Our work shows that a monochromic ghost image can be obtained in the case of RGGP. More importantly, the position (or distance) of the object can be ascertained by the color of the image. Thus, the imaging and ranging processes are combined as one process for the first time to the best of our knowledge. In the case of SLM, we can obtain a colored image regardless of where the object is. Project supported by the National Natural Science Foundation of China (Grant Nos. 61178012, 11204156, 11304179, and 11247240), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant Nos. 20133705110001 and 20123705120002), the Scientific Research Foundation for Outstanding Young Scientists of Shandong Province, China (Grant No. BS2013DX034), and the Natural Science Foundation of Shandong Province, China (Grant No. ZR2012FQ024).

  19. Hypothesis for heritable, anti-viral immunity in crustaceans and insects

    Directory of Open Access Journals (Sweden)

    Flegel Timothy W

    2009-09-01

    Full Text Available Abstract Background It is known that crustaceans and insects can persistently carry one or more viral pathogens at low levels, without signs of disease. They may transmit them to their offspring or to naïve individuals, often with lethal consequences. The underlying molecular mechanisms have not been elucidated, but the process has been called viral accommodation. Since tolerance to one virus does not confer tolerance to another, tolerance is pathogen-specific, so the requirement for a specific pathogen response mechanism (memory was included in the original viral accommodation concept. Later, it was hypothesized that specific responses were based on the presence of viruses in persistent infections. However, recent developments suggest that specific responses may be based on viral sequences inserted into the host genome. Presentation of the hypothesis Non-retroviral fragments of both RNA and DNA viruses have been found in insect and crustacean genomes. In addition, reverse-transcriptase (RT and integrase (IN sequences are also common in their genomes. It is hypothesized that shrimp and other arthropods use these RT to recognize "foreign" mRNA of both RNA and DNA viruses and use the integrases (IN to randomly insert short cDNA sequences into their genomes. By chance, some of these sequences result in production of immunospecific RNA (imRNA capable of stimulating RNAi that suppresses viral propagation. Individuals with protective inserts would pass these on to the next generation, together with similar protective inserts for other viruses that could be amalgamated rapidly in individual offspring by random assortment of chromosomes. The most successful individuals would be environmentally selected from billions of offspring. Conclusion This hypothesis for immunity based on an imRNA generation mechanism fits with the general principle of invertebrate immunity based on a non-host, "pattern recognition" process. If proven correct, understanding the

  20. [Conservation Units.

    Science.gov (United States)

    Texas Education Agency, Austin.

    Each of the six instructional units deals with one aspect of conservation: forests, water, rangeland, minerals (petroleum), and soil. The area of the elementary school curriculum with which each correlates is indicated. Lists of general and specific objectives are followed by suggested teaching procedures, including ideas for introducing the…

  1. Creative conservation

    NARCIS (Netherlands)

    Bentham, Roelof J.

    1968-01-01

    The increasing exploitation of our natural resources, the unlimited occupation of ever more new areas, and the intensification of land-use, make it necessary for us to expand the concept of conservation. But we also need to reconsider that concept itself. For the changing conditions in the present-d

  2. Generalising Conservativity

    OpenAIRE

    Zuber, Richard

    2010-01-01

    A constraint on functions from sets and relations to sets is studied. This constraint is a generalisation of the constraint of conservativity known from the study of generalised quantifiers in natural languages. It is suggested that this generalised constraint constitutes a semantic universal

  3. Controlling of crustacean zooplankton reproduction in biological activated carbon (BAC) filters by strengthen operation and management of conventional process

    Institute of Scientific and Technical Information of China (English)

    LIU Li-jun; ZHANG Jin-song; LI Xiao-wei; HE Jun-guo

    2010-01-01

    To counter the mass reproduction and penetration of crustacean zooplankton in Biological Activated Carbon (BAC) filters which may result in the presence of organisms in potable water and water pollution,this paper analyzed the factors affecting organisms' reproduction in BAC filters.A comparative study was performed on the density and composition of crustacean zooplankton of the concerned water treatment units of two advanced water plants (Plant A and B) which with the same raw water and the same treatment technique in southern China.The results obtained show that the crustaceans' density and composition was very different between the sand filtered water of Plant A and Plant B.which Harpacticoida bred sharply in the sediment tanks and penetrated sand filter into BAC falters was the primary reason of crustaceans reproduce in BAC filters of Plant A.For prevention of the organisms reproduction in BAC,some strengthen measures was taken including pre-chlorination,cleaning coagulation tanks and sediment tanks completely,increasing sludge disposal frequency to stop organisms enter BAC filters,and the finished water quality was improved and enhanced.

  4. 77 FR 50144 - Broad Stakeholder Survey

    Science.gov (United States)

    2012-08-20

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 60-day... comments concerning the Broad Stakeholder Survey. DATES: Comments are encouraged and will be accepted until... across the Nation. The Broad Stakeholder Survey is designed to gather stakeholder feedback on...

  5. 76 FR 34087 - Broad Stakeholder Survey

    Science.gov (United States)

    2011-06-10

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 60-day... comments concerning the Broad Stakeholder Survey. DATES: Comments are encouraged and will be accepted until.... The Broad Stakeholder Survey is designed to gather stakeholder feedback on the effectiveness of...

  6. 78 FR 20119 - Broad Stakeholder Survey

    Science.gov (United States)

    2013-04-03

    ... SECURITY Broad Stakeholder Survey AGENCY: National Protection and Programs Directorate, DHS. ACTION: 30-day... soliciting comments concerning the Broad Stakeholder Survey. DHS previously published this ICR in the Federal... responders across the Nation. The Broad Stakeholder Survey is designed to gather stakeholder feedback on...

  7. Conservation status of Chinese species: (2) Invertebrates.

    Science.gov (United States)

    Xie, Yan; Wang, Sung

    2007-06-01

    A total of 2441 invertebrate species were evaluated using the IUCN Red List Criteria and Regional Guidelines. Approximately 30 experts were involved in this project, which covered a wide range of species, including jellyfish, corals, planarians, snails, mollusks, bivalves, decapods, benthic crustaceans, arachnids (spiders, scorpions), butterflies, moths, beetles, sea cucumbers, sea urchins, sea stars, acorn worms and lancelets. In general, invertebrate species in China were found to be severely threatened, with 0.9% being critically endangered, 13.44% endangered and 20.63% vulnerable. All species of hermatypic corals and planarians are threatened. More than 80% of evaluated species face serious threat due to habitat destruction by coral collection, logging, non-woody vegetation collection, timber plantations, non-timber plantations, extraction and/or livestock. Other threats are intrinsic factors, harvesting by humans, alien invasive species and pollution. The main intrinsic factors contributing to the high levels of threat are limited dispersal and restricted range. No conservation measures have been taken for 70% of the threatened invertebrates evaluated. Existing conservation measures include: strengthening of national and international legislation (Convention on International Trade in Endangered Species of Wild Fauna and Flora), increasing public awareness, studying population trends/monitoring, and establishment of protected areas. The major conservation measure employed is strengthening of policies. Relative to the situation worldwide (2006 IUCN Red List), there is little information available about invertebrate extinctions in China. PMID:21396022

  8. Genotyping of white spot syndrome virus on wild and farm crustaceans from Sonora, Mexico

    Directory of Open Access Journals (Sweden)

    González-Galaviz José Reyes

    2013-01-01

    Full Text Available White spot syndrome is a viral disease affecting wild and farm crustaceans that serve as reservoirs. Previous reports have demonstrated high genomic variation in WSS viruses (WSSV isolated from distinct geographical regions. In this study, we collected wild shrimps (Litopenaeus stylirostris, crabs (Callinectes arcuatus and farmed shrimp (L. vannamei in Sonora, Mexico, between 2008 and 2010. DNA was extracted, and the variable regions and transposase genes were subjected to PCR and sequencing. Compared to strains of WSSV from other sites, Mexican samples exhibited a distinct number of repeat units (RUs in ORF94, ORF75 and ORF125, which ranged between 1-11, 3-15, and 8-11 RUs respectively, and a unique single nucleotide polymorphism (SNP at position 48 of ORF94. A total of six Mexican genotypes were found in organism from shrimp farm and natural environment.

  9. Environmental impact of oil exploration on the crustacean zooplankton of osse river, southern nigeria

    International Nuclear Information System (INIS)

    The impact of crude oil exploration on the crustacean zooplankton of Osse River, Edo State (Nigeria) was investigated at five sites between July 2000 and June 2002. Cladocera accounted for 60.85% of the total number of organisms collected from all the five stations, while Copepoda contributed 39.15%. Chydoridae, the only cladoceran family was represented by 11- taxa of two subfamilies, Aloninae (7) and Chydorinae (4). The overall abundance of Cladocera was significantly different (P < 0.05) among the stations. A posteriori Duncan Multiple Range (DMR) test showed that the abundance of Cladocera was significantly higher (P < 0.05) in 3 stations, whereas, Copepod abundance was significantly higher (P < 0.05) in 2 stations. The diversity indices revealed the highest and the lowest taxa richness, while Shannon-Wiener and Evenness indices were higher in 3 stations. The temporal dynamics revealed higher faunal abundance during the dry season. (author)

  10. Assessment of radionuclide concentration in three crustaceans species of the bay of Bengal

    International Nuclear Information System (INIS)

    The natural (226Ra, 228Th, 232Th and 40K) and anthropogenic (137Cs) radionuclides concentrations in three crustaceans species (Penaeus monodon, Metapenaeus monoceros and Panulirus versicolor), collected from the bay of Bengal, were determined with an aim of assessing any internal radiation hazard due to consumption of the shell fishes and establishing a database for radioactivity levels of the species. Very low level of radioactivity was observed in all the species. The average activity of 226Ra observed in P. monodon was 1.21 ± 0.27 Bq kg-1 fw; in M. monoceros was 0.70 ±0.08 Bq kg-1 fw, and in Panulirus versicolor was 1.04 ± 0.09 Bq kg-1 fw. The activity of 232Th observed in these species was 1.30 ± 0.37, 0.76 ± 0.34 and 1.32 ± 0.70 Bq kg-1 fw, and 228Th was 0.55 ± 0.26, 0.31 ± 0.14 and 0.74 ± 0.22 Bq kg-1 fw, respectively. The average activity of 40K observed in these species was 12.56 ± 1.18, 6.38 ±1.02 and 10.07 ± 1.52 Bq kg-1 fw, respectively. The activity of radiocaesium (137Cs) was below detection limit. The results indicate that the natural and artificial radionuclides observed in three crustaceans species are safe for human health. A significant relationship was observed between 226Ra and 232Th in both the P. monodon (r = 0.839, p ≤ 0.05, df = 4) and the Panulirus versicolor (r = 0.906, p ≤ 0.05, df = 4). (authors)

  11. Self-Assembled, Iridescent, Crustacean-Mimetic Nanocomposites with Tailored Periodicity and Layered Cuticular Structure.

    Science.gov (United States)

    Wang, Baochun; Walther, Andreas

    2015-11-24

    Natural high-performance materials inspire the pursuit of ordered hard/soft nanocomposite structures at high fractions of reinforcements and with balanced molecular interactions. Herein, we develop a facile, waterborne self-assembly pathway to mimic the multiscale cuticle structure of the crustacean armor by combining hard reinforcing cellulose nanocrystals (CNCs) with soft poly(vinyl alcohol) (PVA). We show iridescent CNC nanocomposites with cholesteric liquid-crystal structure, in which different helical pitches and photonic band gaps can be realized by varying the CNC/PVA ratio. We further show that multilayered crustacean-mimetic materials with tailored periodicity and layered cuticular structure can be obtained by sequential preparation pathways. The transition from a cholesteric to a disordered structure occurs for a critical polymer concentration. Correspondingly, we find a transition from stiff and strong mechanical behavior to materials with increasing ductility. Crack propagation studies using scanning electron microscopy visualize the different crack growth and toughening mechanisms inside cholesteric nanocomposites as a function of the interstitial polymer content for the first time. Different extents of crack deflection, layered delamination, ligament bridging, and constrained microcracking can be observed. Drawing of highly plasticized films sheds light on the mechanistic details of the transition from a cholesteric/chiral nematic to a nematic structure. The study demonstrates how self-assembly of biobased CNCs in combination with suitable polymers can be used to replicate a hierarchical biological structure and how future design of these ordered multifunctional nanocomposites can be optimized by understanding mechanistic details of deformation and fracture. PMID:26372330

  12. Characterization of a type-I crustin with broad-spectrum antimicrobial activity from red swamp crayfish Procambarus clarkii.

    Science.gov (United States)

    Liu, Ning; Zhang, Ran-Ran; Fan, Zhen-Xu; Zhao, Xiao-Fan; Wang, Xian-Wei; Wang, Jin-Xing

    2016-08-01

    Crustins are a family of antimicrobial peptides mainly identified in crustaceans and characterized by a whey acidic protein (WAP) domain and an additional glycine-, cysteine-, or proline-rich region. In this study, we identified and characterized PcCru, a new crustin isolated from red swamp crayfish Procambarus clarkii. The open reading frame of PcCru was 333 base pairs long and encoded a 110-residue polypeptide, which contained a signal peptide, a cysteine-rich region, and a WAP domain. The architecture and phylogenetic analysis suggested that PcCru was a new member of the type-I crustin family. PcCru was highly expressed in hemocytes and was significantly induced by viral and bacterial stimulations at both the translational and transcriptional levels. The titer of PcCru in circulating plasma was also increased considerably by bacterial challenge. Recombinant PcCru from both prokaryotic and eukaryotic expression systems were generated, and the proteins exhibited broad-spectrum antimicrobial activity. Furthermore, PcCru protected crayfish from infection by pathogenic bacteria Aeromonas hydrophila in vivo. This study provided new information emphasizing the important role of the crustin family in the crustacean antibacterial immune response. PMID:27021077

  13. Crustaceans from a tropical estuarine sand-mud flat, Pacific, Costa Rica, (1984-1988 revisited

    Directory of Open Access Journals (Sweden)

    José A. Vargas-Zamora

    2012-12-01

    Full Text Available The availability of data sets for time periods of more than a year is scarce for tropical environments. Advances in hardware and software speed-up the re-analysis of old data sets and facilitates the description of population oscillations. Using recent taxonomic literature and software we have updated and re-analized the information on crustacean diversity and population fluctuations from a set of cores collected at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Pacific coast of Costa Rica (1984-1988. A total of 112 morphological species of macroinvertebrates was found, of which 29 were crustaceans. Taxonomic problems, maily with the peracarids, prevented the identification of a group of species. The abundance patterns of the crab Pinnixa valerii, the ostracod Cyprideis pacifica, and the cumacean Coricuma nicoyensis were analized with the Generalized Additive Models of the free software R. The models evidenced a variety of population oscillations during the sampling period. These oscillations probably included perturbations induced by external factors, like the strong red tide events of 1985. In additon, early on 1984 the populations might have been at an altered state due to the inpact of El Niño 1982-83. Thus, the oscillations observed during the study period departed from the expected seasonality (dry vs rainy pattern and are thus considered atypical for this tropical estuarine tidal-flat. Crustacean diversity and population peaks were within the range of examples found in worldwide literature. However, abundances of the cumacean C. nicoyensis, an endemic species, are the highest reported for a tropical estuary. Comparative data from tropical tidal flat crustaceans continues to be scarce. Crustaceans (total vs groups had population changes in response to the deployment of predator exclusion cages during the dry and rainy seasons of 1985. Temporal and spatial patchiness characterized the abundances of P. valeri, C. pacifica and C

  14. The ubiquity of conservative translations

    CERN Document Server

    Jeřábek, Emil

    2011-01-01

    We study the notion of conservative translation between logics introduced by Feitosa and D'Ottaviano. We show that classical propositional logic (CPC) is universal in the sense that every finitary consequence relation over a countable set of formulas can be conservatively translated into CPC. The translation is computable if the consequence relation is decidable. More generally, we show that one can take instead of CPC a broad class of logics (extensions of a certain fragment of full Lambek calculus FL) including most nonclassical logics studied in the literature, hence in a sense, (almost) any two reasonable deductive systems can be conservatively translated into each other. We also provide some counterexamples, in particular the paraconsistent logic LP is not universal.

  15. Ingestion and selection of suprabenthic crustaceans by small-sized fishes in a lower saltmarsh system

    Directory of Open Access Journals (Sweden)

    Yoko Wakabara

    1996-01-01

    Full Text Available This study was performed in the lower saltmarsh system of the Arrozal, in the Cananéia lagoon estuarine region (25º02'S - 47º56'W, Brazil. Suprabenthic fauna was surveyed Wlth a small sledge and fishes were captured with casting and set nets to analyse: crustacean fauna as food for local fish species; difference in the diet at different times of the year; if there is diet overlap between species and the feeding behaviour of the species analysed. The fauna of Arrozal is poor in species, dominated mainly by Metamysidopsis alongata atlantica, Acartia lilljeborgi, Atylus minikoi, decapod larvae, and reveals a strong seasonal variation. The fishes were ali camivorous with suprabenthic crustacean as their main food resource. Seasonal changes in food supply are also reflected in the diet. Of the 12 flSh species collected six were opportunistlc feeders whereas six others were selective feeders. Food overlap value of 0.08 for ali of the fish community indicates an almost completely distinct food niches. The increased overlapping of summer food between Cathorops spixii and species of Group 11 and between Oligoplites sp and species of Group I seems to have two different explanations: 1 the mmIDishing of food supply for species feeding on benthic originated suprabenthic crustaceans and 2 overabundance of planktonic forms of suprabenthos as well as a period of high feeding activity of fishes with such diet.O presente estudo foi realizado no infralitoral contíguo à marisma, na Ponta do Arrozal, região estuarina lagunar de Cananéia (25º02'S - 47º56'W, Brasil. A fauna suprabêntica foi amostrada com uma pequena draga e os peixes capturados com tarrafa e rede de espera, com a finalidade de analisar: a composição de espécies dos crustáceos suprabênticos como itens alimentares dos peixes; diferenças na dieta em diferentes época do ano; se ocorre sobreposição alimentar entre as espécies e o comportamento alimentar: das espécies de peixes

  16. Distributional patterns of decapod crustaceans in the circum-Mediterranean area during the Oligo-Miocene

    Science.gov (United States)

    Hyžný, Matúš

    2015-04-01

    During the Oligocene and Miocene, the circum-Mediterranean area was a complex network of (mostly) shallow marine basins. Significant biogeographic differentiation of this area has been documented (Harzhauser et al. 2007), mainly during the Miocene, when connections between Proto-Mediterranean, Paratethys and Proto-Indo-West Pacific were intermittently opening and closing. These seaways allowed migration of marine faunas. Distributional patterns has so far been discussed for several different animal groups, especially for molluscs (e.g. Studencka et al. 1998; Harzhauser et al. 2002, 2003, 2007). To test these patterns with decapod crustaceans, a database has been compiled including all previously published Oligocene and Miocene decapod occurrences and newly gathered data from examined material deposited in the institutional collections. Decapod associations have been significant components of marine habitats since the Mesozoic times with ever-increasing importance throughout the Cenozoic. Müller (1979) argued that brachyuran decapods are among the best zoogeographical indicators. Although decapods were used as such indicators before (e.g. Schweitzer 2001; Feldmann & Schweitzer 2006), no detailed analysis of the circum-Mediterranean taxa has been conducted so far. Based on proposed anti-estuarine circulation pattern, decapods originated in the Proto-Mediterranean, and migrated both into the North Sea and the Paratethys. Moreover, during the Early Miocene the Rhine Graben served as a connection between the North Sea and the Paratethys which enabled faunal exchange. The Middle Miocene Proto-Mediterranean and Paratethys decapod assemblages as taken together were relatively homogeneous, although distinct due to increasing rate of endemites in the Paratethys during the Miocene. The research has been supported by FWF: Lise Meitner Program M 1544-B25. References Feldmann R.M. & Schweitzer C.E. 2006: Paleobiogeography of Southern Hemisphere decapod Crustacea. J. Paleontol

  17. Cuticular Biominerals of the Terrestrial Crustacean Oniscus asellus (Isopoda, Linnaeus 1758)

    Science.gov (United States)

    Mergelsberg, S. T.; Mukhopadhyay, B.; Dove, P. M.

    2013-12-01

    Biomineralization is a phenomenon observed in many eukaryotic organisms and evidence suggests this process began relatively early in the evolution of multicellular life (Marin F et al. 1996). Crustaceans form a large fraction of all eukaryotic biomineralizers by incorporating calcium carbonate (CaCO3) into their cuticle. Terrestrial species are challenged in their production of CaCO3 by the absence of calcium-rich waters. To cope with this limitation, the terrestrial crustacean Oniscus asellus recycles up to 80% (Auzou G 1953) of its total calcium during the molting process. This feat is accomplished by separate molting of the front and back cuticle, with temporary storage of the calcium carbonate as amorphous calcium carbonate (ACC) in the front half (Ziegler A 1997). These processes infer a highly efficient and regulated mechanism for biomineralization that is most likely orchestrated by a myriad of proteins (Ziegler A et al. 2012). Until recently, investigations of biomineralization were largely directed toward understanding morphology and large-scale chemistry of the minerals, ignoring the mechanistic roles of biomacromolecules in mineralization processes. More recent work suggests a high involvement of these compounds on the formation of biominerals and, in some cases, the specific polymorphs thereof (Keene EC et al. 2010). This study focuses on identifying the components of the biological mineralization matrix at each stage of the process. Using chemical demineralization of the stored ACC, all biomacromolecules can be separated and purified for subsequent analysis by MALDI-TOF mass spectrometry. To link the localized biochemistry more intimately to the polymorph of calcium carbonate that forms in the animal, the inorganic phase (';the mineral') will be monitored at each life stage using XRD and TEM. This analysis will reveal the organic components of a very precise biomineralization mechanism and may shed insight on its evolutionary origin. References: Marin

  18. Differential expression profiling of components associated with exoskeletal hardening in crustaceans

    Directory of Open Access Journals (Sweden)

    Kuballa Anna V

    2008-12-01

    Full Text Available Abstract Background Exoskeletal hardening in crustaceans can be attributed to mineralization and sclerotization of the organic matrix. Glycoproteins have been implicated in the calcification process of many matrices. Sclerotization, on the other hand, is catalysed by phenoloxidases, which also play a role in melanization and the immunological response in arthropods. Custom cDNA microarrays from Portunus pelagicus were used to identify genes possibly associated with the activation pathways involved in these processes. Results Two genes potentially involved in the recognition of glycosylation, the C-type lectin receptor and the mannose-binding protein, were found to display molt cycle-related differential expression profiles. C-type lectin receptor up-regulation was found to coincide with periods associated with new uncalcified cuticle formation, while the up-regulation of mannose-binding protein occurred only in the post-molt stage, during which calcification takes place, implicating both in the regulation of calcification. Genes presumed to be involved in the phenoloxidase activation pathway that facilitates sclerotization also displayed molt cycle-related differential expression profiles. Members of the serine protease superfamily, trypsin-like and chymotrypsin-like, were up-regulated in the intermolt stage when compared to post-molt, while trypsin-like was also up-regulated in pre-molt compared to ecdysis. Additionally, up-regulation in pre- and intermolt stages was observed by transcripts encoding other phenoloxidase activators including the putative antibacterial protein carcinin-like, and clotting protein precursor-like. Furthermore, hemocyanin, itself with phenoloxidase activity, displayed an identical expression pattern to that of the phenoloxidase activators, i.e. up-regulation in pre- and intermolt. Conclusion Cuticle hardening in crustaceans is a complex process that is precisely timed to occur in the post-molt stage of the molt cycle

  19. Measuring and incorporating vulnerability into conservation planning.

    Science.gov (United States)

    Wilson, Kerrie; Pressey, Robert L; Newton, Adrian; Burgman, Mark; Possingham, Hugh; Weston, Chris

    2005-05-01

    Conservation planning is the process of locating and designing conservation areas to promote the persistence of biodiversity in situ. To do this, conservation areas must be able to mitigate at least some of the proximate threats to biodiversity. Information on threatening processes and the relative vulnerability of areas and natural features to these processes is therefore crucial for effective conservation planning. However, measuring and incorporating vulnerability into conservation planning have been problematic. We develop a conceptual framework of the role of vulnerability assessments in conservation planning and propose a definition of vulnerability that incorporates three dimensions: exposure, intensity, and impact. We review and categorize methods for assessing the vulnerability of areas and the features they contain and identify the relative strengths and weaknesses of each broad approach. Our review highlights the need for further development and evaluation of approaches to assess vulnerability and for comparisons of their relative effectiveness. PMID:15920667

  20. Broad Prize: Do the Successes Spread?

    Science.gov (United States)

    Samuels, Christina A.

    2011-01-01

    When the Broad Prize for Urban Education was created in 2002, billionaire philanthropist Eli Broad said he hoped the awards, in addition to rewarding high-performing school districts, would foster healthy competition; boost the prestige of urban education, long viewed as dysfunctional; and showcase best practices. Over the 10 years the prize has…

  1. Scientific Opinion on the safety and efficacy of synthetic astaxanthin as feed additive for salmon and trout, other fish, ornamental fish, crustaceans and ornamental birds

    OpenAIRE

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)

    2014-01-01

    Astaxanthin is a pigmenting carotenoid occurring naturally in plankton, crustaceans and fish. The astaxanthin under assessment is of synthetic origin. The FEEDAP Panel considers synthetic astaxanthin safe for salmonids up to 100 mg/kg complete diet. The conclusion on the safety of astaxanthin for salmonids can be extrapolated to other fish and ornamental fish at the same dose. Dietary concentrations of up to 100 mg astaxanthin/kg feed are safe for crustaceans. The FEEDAP Panel could not concl...

  2. A long-term study on crustacean plankton of a shallow tropical lake: the role of invertebrate predation

    Directory of Open Access Journals (Sweden)

    Marlene S. Arcifa

    2015-06-01

    Full Text Available The primary factor that governs the size and species composition of zooplankton is still a controversial issue and temperature is considered the main factor responsible for latitudinal differences. In waters with a narrow temperature range, such as in the tropics, predation may be a more important factor. Nearly three decades of intermittent studies of the crustacean plankton in a shallow tropical lake revealed that the main event that led to their restructuring was the appearance of a second predator, the water mite Krendowskia sp. The new predator and larvae of the dipteran Chaoborus brasiliensis Theobald exerted a combined, although asymmetrical effect on microcrustaceans. The period when the mite was detected was followed by the restructuring of the crustacean plankton community. Predation by these two invertebrates emerged as the factor responsible for community changes, involving an increased contribution of copepods and decreases in the relative abundance of smaller cladoceran species. In the short term, the mite caused a decrease in species richness and the annual mean instantaneous composition of cladocerans, a predominance of large-sized species (Daphnia ambigua Scourfield and Daphnia gessneri Herbst and the virtual disappearance of small species (e.g., Bosmina tubicen Brehm. The long-term impact resulted in increased species richness and the dominance of large and medium-sized cladocerans, such as D. gessneri and Ceriodaphnia richardi Sars. The larger body size of three cladocerans, the two Daphnia species and B. tubicen, in the long term, may be a response to the dominant predator, Chaoborus. The seasonal variation in the predator abundance, mainly Chaoborus larvae, allowed the prey to recover during the cool season. The copepods Tropocyclops prasinus meridionalis (Fischer and Thermocyclops decipiens Kiefer were less affected by predation than the cladocerans; their contribution to the crustacean plankton increased 12-28% after the

  3. Distribution of relic crustaceans in the deep lakes of Karelia in connection with geological features of the region

    OpenAIRE

    Kalinkina Nataliya Mikhailovna

    2015-01-01

    The geographical location of deep-water lakes in Karelia was analyzed using the correlation and regression analysis methods. It was shown that the position of lakes is confined to the Central Karelian zone of active faults extending to the northwest. The connection between the deep-water lakes location and Central Karelian fault zone was confirmed statistically. In deep lakes of Karelia there exist relic crustaceans, that is associated with low temperature in bottom water layers in the summer...

  4. Multidisciplinary study of the trophic diversity and functional role of amphipod crustaceans associated to Posidonia oceanica meadows

    OpenAIRE

    Michel, Loïc; Lepoint, Gilles; Gobert, Sylvie; Dauby, Patrick

    2009-01-01

    Posidonia oceanica is a seagrass endemic to the Mediterranean Sea, and is able to form large monospecific areas, called meadows. These meadows are critical features of the Mediterranean coastal zones, and are of great ecologic and economic importance. Posidonia oceanica meadows shelter high biomasses and biodiversities of amphipod crustaceans. In other temperate meadows, such as Atlantic Zostera marina meadows, the amphipods play an important part in the functioning of the ecosystem, notab...

  5. Changes in the non-crustacean zooplankton community in the middle Adriatic Sea during the Eastern Mediterranean Transient

    OpenAIRE

    Batistić, Mirna; Garić, Rade; MOROVIĆ, Mira

    2016-01-01

    Background and Purpose: Here we presented changes in the non-crustacean zooplankton community in the years characterized by the large scale changes in the thermohaline circulation in the East Mediterranean known as the Eastern Mediterranean transient (EMT) and stronger inflow of colder and less saline Modified Atlantic Water (MAW) into the Adriatic Sea. Material and Method: Monthly samplings from February 1995 to February 1996, were performed at fixed station Stončica near the Island of V...

  6. Size influence in zonation patterns in fishes and crustaceans from deep- water communities of the Western Mediterranean

    OpenAIRE

    Morales-Nin, Beatriz; Maynou, Francesc; Sardà, Francisco; Cartes, Joan Enric; Moranta, Joan; Massutí, Enric; Company, Joan B.; Rotllant, Guiomar; Bozzano, Anna; Stefanescu, Constantino

    2003-01-01

    Information was collected over two seasons on the depth distribution of the deep-water fishes and decapod crustaceans to the southwest of the Balearic Islands. The data were analysed to compared the intensity of faunal change with depth to individual size, measured as mean individual weight, both within and between fish and decapods. The results are discussed on the light of the biological characteristics of the populations studied. We conclude that there are complex distributions of mean wei...

  7. Lyme disease and conservation

    Science.gov (United States)

    Ginsberg, H.

    1994-01-01

    Lyme disease is a tick-borne illness that is wide-spread in North America, especially in the northeastern and northcentral United States. This disease could negatively influence efforts to conserve natural populations in two ways: (1) the disease could directly affect wild animal health; and (2) tick control efforts could adversely affect natural populations and communities. Lyme disease affects several domestic animals, but symptoms have been reported in only a few wild species. Direct effects of Lyme disease on wild animal populations have not been reported, but the disease should be considered as a possible cause in cases of unexplained population declines in endemic areas. Methods available to manage ticks and Lyme disease include human self-protection techniques, manipulation of habitats and hosts species populations, biological control, and pesticide applications. The diversity of available techniques allows selection of approaches to minimize environmental effects by (1) emphasizing personal protection techniques, (2) carefully targeting management efforts to maximize efficiency, and (3) integrating environmentally benign techniques to improve management while avoiding broad-scale environmentally destructive approaches. The environmental effects of Lyme disease depend, to a large extent, on the methods chosen to minimize human exposure to infected ticks. Conservation biologists can help design tick management programs that effectively lower the incidence of human Lyme disease while simultaneously minimizing negative effects on natural populations.

  8. Dormant stages of crustaceans as a mechanism of propagation in the extreme and unpredictable environment in the Crimean hypersaline lakes

    Science.gov (United States)

    Shadrin, Nickolai V.; Anufriieva, Elena V.; Amat, Francisco; Eremin, Oleg Yu.

    2015-11-01

    A pool of dormant stages of planktonic organisms in saline lakes is a substantial component in the plankton communities; we need to take it into account to understand plankton dynamics. Hypersaline water bodies in Crimea, the largest peninsula in the Black Sea, constitute a very characteristic and peculiar habitat type in the region. We examined the presence of crustacean resting stages in sediments of dried up sites of the Crimean hypersaline lakes. Sediment samples were taken in 9 different lakes. Experiments performed on the hatching of these resting stages showed the presence of Moina salina (Cladocera), parthenogenetic Artemia and Artemia urmiana (Anostraca), Eucypris mareotica ( inflata) (Ostracoda), and Cletocamptus retrogressus (Harpacticoida). Comparing the experimental results obtained with clean dried brine shrimp cysts and those kept in sediment samples, it was noted that clean cysts hatched much faster than those from sediments did. Some components in bottom sediments slow down and desynchronize hatching from resting eggs in different groups of crustaceans. The sediments of different lakes inhibited the nauplii output from Artemia and ostracod resting eggs to different degrees. More data are needed before we can discuss the reasons of this inhibition. The nonsynchronous output of active stages from the bottom resting ones may be an adaptation that allows crustacean species to exist in extreme and unpredictably changing environments, avoiding the risk that all may emerge at once under unsuitable conditions.

  9. Constructing Conservation Impact: Understanding Monitoring and Evaluation in Conservation NGOs

    Directory of Open Access Journals (Sweden)

    Catherine Benson Wahlén

    2014-01-01

    Full Text Available A growing number of scholars critically examine large conservation organisations to explore organisational intentions, practices, and outcomes. In parallel, other scholars have problematised audit cultures, suggesting that these seemingly good practices of evaluation and measurement are not neutral and instead have consequences for governance and power. This article combines literature on conservation NGOs, organisational theory, and audit culture to study the inner workings of conservation and to understand the construction of effectiveness and impact. I draw on semi-structured interviews to examine how a large, international conservation organisation, which I term the World Conservation Organisation (WCO; a pseudonym, coordinates monitoring and evaluation (M&E processes among its international, national, and local offices. I find individual staff within WCO make varying assumptions about the M&E policies and place different values on M&E, which results in different institutional logics towards M&E and a broader organisational failure to measure progress and reflect upon outcomes. The findings also show difficulties in translating broad organisational goals into specific project activities, underscoring tensions in implementation and limitations in M&E practice. I also find that organisational and managerial pressure to report success is greater than donor pressure, a finding that expands understandings of NGO-donor dynamics.

  10. Heading which way? Y-maze chemical assays: not all crustaceans are alike

    Science.gov (United States)

    Kenning, Matthes; Lehmann, Philipp; Lindström, Magnus; Harzsch, Steffen

    2015-09-01

    In a world full of chemicals, many crustaceans rely on elaborate olfactory systems to guide behaviors related to finding food or to assess the presence of conspecifics and predators. We analyzed the responses of the isopod Saduria entomon to a range of stimuli by which the animal is likely to encounter in its natural habitat using a Y-maze bioassay. In order to document the efficiency of the experimental design, the same bioassay was used to test the behavior of the crayfish Procambarus fallax whose ability to track odors is well documented. The crayfish performed well in the Y-maze and were able to locate the source of a food-related odor with high fidelity. The isopod S. entomon reacted indifferently or with aversion to most of the stimuli applied. In 1800 trials, only four out of 15 different stimuli yielded statistically significant results, and only one odorant was found to be significantly attractive. The findings raise several questions whether the stimuli presented and/or the experimental setup used represents an ecologically relevant situation for S. entomon. In each instance, our experiments illustrate that established methods cannot be readily transferred from one species to another.

  11. Tellurium-speciation in seawater and accumulation by marine phytoplankton and crustaceans

    International Nuclear Information System (INIS)

    Experiments were performed to determine the speciation of tellurium (using 129mTe as a radiotracer) in seawater and the extent of its accumulation by cultures of marine phytoplankton and crustaceans. Tellurite Te(IV) added to distilled water and to sterile filtered seawater was gradually transformed to the tellurate Te(VI) form, whereas Te(IV) tracer added to phytoplankton cultures was almost instantaneously transformed to a neutral form. Accumulation of radiotracer by phytoplankton (Dunaliella tertiolecta and Thallassiosira pseudonana) was moderate and for Dunaliella was greater in static cultures than in those which were actively dividing. Equilibrium concentration factors of 20 and 8 were established respectively after up to seven days' exposure of the herbivorous brine shrimp (Artemia salina) to labelled seawater with and without added phytoplankton. The loss of radionuclide upon transfer to uncontaminated running seawater was extensive and complete after one day, indicating that no true assimilation occurred. Transfer of radioactivity from Artemia salina to a predator, the Monaco shrimp (Lysmata seticaudata), was not observed. (author)

  12. The trophic importance of algal turfs for coral reef fishes: the crustacean link

    Science.gov (United States)

    Kramer, M. J.; Bellwood, O.; Bellwood, D. R.

    2013-06-01

    On coral reefs, the epilithic algal matrix (EAM) is widely recognised as an important resource for herbivorous and detritivorous fishes. In comparison, little is known of the interaction between benthic carnivores and the EAM, despite the abundance of Crustacea within the EAM. The trophic importance of the EAM to fishes was investigated in Pioneer Bay, Orpheus Island, Great Barrier Reef. Fish densities were quantified using visual and clove oil censuses, and gut content analyses conducted on abundant fish species. Crustaceans were found to be an important dietary category, contributing between 49.5 and 100 % of the gut contents, with harpacticoid copepods being the dominant component. Of the benthic carnivores, the goby Eviota zebrina was found to consume the most harpacticoids with a mean of 249 copepods m-2 day-1. This represents approximately 0.1 % of the available harpacticoid population in the EAM. In a striking comparison, herbivorous parrotfishes were estimated to consume over 12,000 harpacticoids m-2 day-1, over 27 times more than all benthic carnivores surveyed, representing approximately 5.3 % of the available harpacticoid copepod population each day. The high consumption of harpacticoid copepods by benthic carnivores and parrotfishes indicates that harpacticoids form an important trophic link between the EAM and higher trophic levels on coral reefs.

  13. Fitness and virulence of a bacterial endoparasite in an environmentally stressed crustacean host.

    Science.gov (United States)

    Coors, Anja; De Meester, Luc

    2011-01-01

    Host-parasite interactions are shaped by the co-evolutionary arms race of parasite virulence, transmission success as well as host resistance and recovery. The virulence and fitness of parasites may depend on host condition, which is mediated, for instance, by host energy constraints. Here, we investigated to what extent stress imposed by predation threat and environmental pollutants influences host-parasite interactions. We challenged the crustacean host Daphnia magna with the sterilizing bacterial endoparasite Pasteuria ramosa and simultaneously exposed the host to fish kairomones, the pesticide carbaryl or both stressors. While parasite virulence, measured as impact on host mortality and sterilization, increased markedly after short-term pesticide exposure, it was not influenced by predation threat. Parasite fitness, measured in terms of produced transmission stages, decreased both in fish and pesticide treatments. This effect was much stronger under predation threat than carbaryl exposure, and was attributable to reduced somatic growth of the host, presumably resulting in fewer resources for parasite development. While the indirect impact of both stressors on spore loads provides evidence for host condition-dependent parasite fitness, the finding of increased virulence only under carbaryl exposure indicates a stronger physiological impact of the neurotoxic chemical compared with the effect of a non-toxic fish kairomone. PMID:20663250

  14. Reproduction recovery of the crustacean Daphnia magna after chronic exposure to ibuprofen.

    Science.gov (United States)

    Hayashi, Yuya; Heckmann, Lars-Henrik; Callaghan, Amanda; Sibly, Richard M

    2008-05-01

    In mammals, the pharmaceutical ibuprofen (IB), a non-steroidal anti-inflammatory drug, primarily functions by reversibly inhibiting the cyclooxygenase (COX) pathway in the synthesis of eicosanoids (e.g. prostaglandins). Previous studies suggest that IB may act in a similar manner to interrupt production of eicosanoids reducing reproduction in the model crustacean Daphnia magna. On this basis withdrawal of IB should lead to the recovery of D. magna reproduction. Here we test whether the effect of IB is reversible in D. magna, as it is in mammals, by observing reproduction recovery following chronic exposure. D. magna (5-days old) were exposed to a range of IB concentrations (0, 20, 40 and 80 mg l(-1)) for 10 days followed by a 10 day recovery period in uncontaminated water. During the exposure period, individuals exposed to higher concentrations produced significantly fewer offspring. Thereafter, IB-stressed individuals produced offspring faster during recovery, having similar average population growth rates (PGR) (1.15-1.28) to controls by the end of the test. It appears that maternal daphnids are susceptible to IB during egg maturation. This is the first recorded recovery of reproduction in aquatic invertebrates that suffered reproductive inhibition during chronic exposure to a chemical stressor. Our results suggest a possible theory behind the compensatory fecundity that we referred to as 'catch-up reproduction'. PMID:18214676

  15. Behaviour of fish by-catch in the mouth of a crustacean trawl.

    Science.gov (United States)

    Queirolo, D; Gaete, E; Montenegro, I; Soriguer, M C; Erzini, K

    2012-06-01

    The behaviour of fish by-catch was recorded and characterized by in situ observations in the mouth of a crustacean trawl using an underwater camera system with artificial light, at depths between 106 and 461 m, along the central coast of Chile. The groups or species studied were rattails (family Macrouridae), Chilean hake Merluccius gayi gayi, sharks (orders Carcharhiniformes and Squaliformes), skates (family Rajidae), flatfishes (genus Hippoglossina) and small benthopelagic and demersal fishes (orders Osmeriformes, Stomiiformes, Gadiformes, Ophidiiformes and Perciformes). The fish behaviour was categorized in terms of (1) position in the water column, (2) initial orientation with respect to the trawl, (3) locomotion and (4) swimming speed with respect to the trawl. Rattails, sharks, skates and flatfishes were passive in response to the trawl and showed similar behavioural patterns, with most fishes observed sitting or touching the bottom with no swimming or other activity. Merluccius gayi gayi was the most active species, displaying a wide combination of behavioural responses when the trawl approached. This species showed several behavioural patterns, mainly characterized by swimming forward at variable speed. A fraction of small bentho-pelagic and demersal fishes also showed an active behaviour but always at lower speed than the trawl. The species-specific differences in behaviour in the mouth of the trawl suggest that improvements at the level of the footrope can be made to reduce by-catch, especially of passive species. PMID:22650431

  16. Description of two new associated infaunal decapod crustaceans (Axianassidae and Alpheidae from the tropical eastern Pacific

    Directory of Open Access Journals (Sweden)

    Arthur Anker

    2015-08-01

    Full Text Available Two new species of infaunal decapod crustaceans are described based on material collected in Bahía Málaga, Pacific coast of Colombia, in 2009. The mud-shrimp Axianassa darrylfelderi sp. nov. (Axianassidae appears to be most closely related to A. australis Rodrigues & Shimizu, 1992, A. canalis Kensley & Heard, 1990, and A. jamaicensis Kensley & Heard, 1990. The new species may be distinguished from each of them by a combination of morphological features, mainly on the uropodal exopod, antennal acicle, third maxilliped and first pleonite. The shrimp Leptalpheus canterakintzi sp. nov. (Alpheidae, associated with burrows of A. darrylfelderi sp. nov., undoubtedly represents the eastern Pacific sister species of the western Atlantic L. axianassae Dworschak & Coelho, 1999, which lives exclusively in burrows of A. australis. The two species are reliably distinguishable only by the proportions of the merus and propodus of the third pereiopod. Leptalpheus azuero Anker, 2011, previously known only from the Pacific coast of Panama, is reported for the first time from Bahía Málaga, Colombia.

  17. A 365-Million-Year-Old Freshwater Community Reveals Morphological and Ecological Stasis in Branchiopod Crustaceans.

    Science.gov (United States)

    Gueriau, Pierre; Rabet, Nicolas; Clément, Gaël; Lagebro, Linda; Vannier, Jean; Briggs, Derek E G; Charbonnier, Sylvain; Olive, Sébastien; Béthoux, Olivier

    2016-02-01

    Branchiopod crustaceans are represented by fairy, tadpole, and clam shrimps (Anostraca, Notostraca, Laevicaudata, Spinicaudata), which typically inhabit temporary freshwater bodies, and water fleas (Cladoceromorpha), which live in all kinds of freshwater and occasionally marine environments [1, 2]. The earliest branchiopods occur in the Cambrian, where they are represented by complete body fossils from Sweden such as Rehbachiella kinnekullensis [3] and isolated mandibles preserved as small carbonaceous fossils [4-6] from Canada. The earliest known continental branchiopods are associated with hot spring environments [7] represented by the Early Devonian Rhynie Chert of Scotland (410 million years ago) and include possible stem-group or crown-group Anostraca, Notostraca, and clam shrimps or Cladoceromorpha [8-10], which differ morphologically from their modern counterparts [1, 2, 11]. Here we report the discovery of an ephemeral pool branchiopod community from the 365-million-year-old Strud locality of Belgium. It is characterized by new anostracans and spinicaudatans, closely resembling extant species, and the earliest notostracan, Strudops goldenbergi [12]. These branchiopods released resting eggs into the sediment in a manner similar to their modern representatives [1, 2]. We infer that this reproductive strategy was critical to overcoming environmental constraints such as seasonal desiccation imposed by living on land. The pioneer colonization of ephemeral freshwater pools by branchiopods in the Devonian was followed by remarkable ecological and morphological stasis that persists to the present day. PMID:26776738

  18. Transforming nanostructured chitin from crustacean waste into beneficial health products: a must for our society

    Directory of Open Access Journals (Sweden)

    Morganti P

    2011-12-01

    Full Text Available P Morganti1, G Morganti2, A Morganti3,41Department of Dermatology, Second University of Naples, Naples, Italy; 2Centre of Nanoscience, Mavi Sud s.r.l, Aprilia, Italy; 3Max Planck Institute for Intellectual Property and Competition Law, Munich, Germany; 4Lextray, Milan, ItalyAbstract: Chitin, obtained principally from crustacean waste, is a sugar-like polymer that is available at low cost. It has been shown to be bio- and ecocompatible, and has a very low level of toxicity. Recently, it has become possible to industrially produce pure chitin crystals, named "chitin nanofibrils" (CN for their needle-like shape and nanostructured average size (240 × 5 × 7 nm. Due to their specific chemical and physical characteristics, CN may have a range of industrial applications, from its use in biomedical products and biomimetic cosmetics, to biotextiles and health foods. At present, world offshore disposal of this natural waste material is around 250 billion tons per year. It is an underutilized resource and has the potential to supply a wide range of useful products if suitably recycled, thus contributing to sustainable growth and a greener economy.Keywords: chitin nanofibrils, biomimetic cosmetics, biomedical products, food, nanotechnology, waste

  19. Crystallization and X-ray diffraction studies of crustacean proliferating cell nuclear antigen

    International Nuclear Information System (INIS)

    Proliferating cell nuclear antigen from Litopenaeus vannamei was recombinantly expressed, purified and crystallized. Diffraction data were obtained and processed to 3 Å. Proliferating cell nuclear antigen (PCNA), a member of the sliding clamp family of proteins, interacts specifically with DNA replication and repair proteins through a small peptide motif called the PCNA-interacting protein or PIP box. PCNA is recognized as one of the key proteins involved in DNA metabolism. In the present study, the recombinant PCNA from Litopenaeus vannamei (LvPCNA) was heterologously overexpressed and purified using metal ion-affinity chromatography. Crystals suitable for diffraction grew overnight using the hanging-drop vapour-diffusion method. LvPCNA crystals belong to space group C2 with unit-cell parameters a = 144.6, b = 83.4, c = 74.3 Å, β = 117.6°. One data set was processed to 3 Å resolution, with an overall Rmeas of 0.09 and a completeness of 93.3%. Initial phases were obtained by molecular replacement using a homology model of LvPCNA as the search model. Refinement and structural analysis are underway. This report is the first successful crystallographic analysis of a marine crustacean decapod shrimp (L. vannamei) proliferating cell nuclear antigen

  20. Ovary and embryo proteogenomic dataset revealing diversity of vitellogenins in the crustacean Gammarus fossarum.

    Science.gov (United States)

    Trapp, Judith; Gaillard, Jean-Charles; Chaumot, Arnaud; Geffard, Olivier; Pible, Olivier; Armengaud, Jean

    2016-09-01

    Ovaries and embryos from sexually mature Gammarus fossarum were sampled at different stages of the reproductive cycle. The soluble proteome was extracted for five biological replicates and samples were subjected to trypsin digestion. The resulting peptides were analyzed by high resolution tandem mass spectrometry with a LTQ-Orbitrap XL instrument. The MS/MS spectra were assigned with a previously described RNAseq-derived G. fossarum database. The proteins highlighted by proteogenomics were monitored and their abundance kinetics over the different stages revealed a large panel of vitellogenins. Criteria were i) accumulation during oogenesis, ii) decrease during embryogenesis, iii) classified as female-specific, and iv) sequence similarity and phylogenetic analysis. The data accompanying the manuscript describing the database searches and comparative analysis ("High-throughput proteome dynamics for discovery of key proteins in sentinel species: unsuspected vitellogenins diversity in the crustacean Gammarus fossarum" by Trapp et al. [1]) have been deposited to the ProteomeXchange via the PRIDE repository with identifiers PRIDE: PXD001002. PMID:27547807

  1. Endangered cave crustacean could be water quality indicator in Illinois Karst Region

    Science.gov (United States)

    Showstrack, Randy

    Some of the rolling, rural countryside of southwestern Illinois has become just a 20-minute commute from the sprawling city of St. Louis, Missouri, across the Mississippi River, now that newly built roads have opened up the landscape. But as more houses rise in rapidly developing bedroom communities, increasing levels of coliform bacteria—probably originating from septic systems and livestock—are being found in the groundwater. Trace amounts of pesticides, including atrazine, also are present.These contaminants, in large enough quantities, can pollute groundwater and cause public health problems. They also appear to be responsible for the decreased habitat and population of a little-known cave-dwelling crustacean, the Illinois Cave Amphipod (Gammarus acherondytes), a tailless shrimp that can grow up to 20 mm in length and that swims in underground streams in cave dark zones. Decreased dissolved oxygen content in the streams, resulting from land development activities that can cause faster surface runoff, also may affect the amphipod.

  2. Seaweed, fish and Crustaceans as bioindicators for {sup 99}Tc released to marine environment[Radioecology

    Energy Technology Data Exchange (ETDEWEB)

    Jerpetjoen, A.; Oughton, D.; Skipperud, l. [Norwegian Univ. of Life Sciences, Dept. of Plant and Environmental Sciences, Aas (Norway)

    2006-04-15

    Along the Norwegian coast, {sup 99}Tc discharged from nuclear installations is found in seaweed, Crustaceans and fish. The activity concentrations of {sup 99}Tc in seaweed peaked around July 2002, giving a concentration ratio (CF) for the stems up to 121 m{sup 3}/Kg. The CF in different marine organisms differs between species, and within species; however, the CF is found to be highest for lobster, 4210 and 3755 m{sup 3}/Kg in the Irish Sea and 68 to 158 m{sup 3}/Kg along the Norwegian coast. {sup 99}Tc activity concentrations in Crabs from the Norwegian coast ranged from 0.12 to 0.61 Bq/kg giving CF's in Crab ranging from 0.24 to 1.22 m{sup 3}/Kg. Salmon filet collected from Norwegian fish farms showed CF levels ranging from 0.21 to 1.39 m{sup 3}/Kg, whereas Herring showed CF values of 0.08 and 0.16 m{sup 3}/Kg. Overall the data varies a lot, which is a problem when measuring natural organisms. Habitat, growth, and eating habits are among many different factors influencing the uptake of {sup 99}Tc. Further investigation on CF and how {sup 99}Tc are obtained by different species in the marine environment, and also different organs of the organisms, is needed. (au)

  3. Birth, survival and differentiation of neurons in an adult crustacean brain.

    Science.gov (United States)

    Kim, Youngmi Faith; Sandeman, David C; Benton, Jeanne L; Beltz, Barbara S

    2014-06-01

    Life-long neurogenesis is a characteristic feature of many vertebrate and invertebrate species. In decapod crustaceans, new neurons are added throughout life to two cell clusters containing local (cluster 9) and projection (cluster 10) interneurons in the olfactory pathway. Adult-born neurons in clusters 9 and 10 in crayfish have the anatomical properties and chemistry of mature neurons by 6 months after birth. Here we use 5-bromo-2'-deoxyuridine (BrdU) incorporation to pulse label mitotically active cells in these cell clusters, followed by a survival time of up to 8 months, during which crayfish (Cherax destructor) were sacrificed at intervals and the numbers of BrdU-labeled cells quantified. We find a decrease in the numbers of BrdU-labeled cells in cell cluster 10 between the first and second weeks following BrdU exposure, suggesting a period of cell death shortly after proliferation. Additional delayed cell divisions in both cell clusters are indicated by increases in labeled cells long after the BrdU clearing time. The differentiation time of these cells into neurons was defined by detection of the first immunoreactivity for the transmitter SIFamide in cluster 10 BrdU-labeled cells, which begins at 4 weeks after BrdU labeling; the numbers of SIFamide-labeled cells continues to increase over the following month. Experiments testing whether proliferation and survival of Cluster 10 cells are influenced by locomotor activity provided no evidence of a correlation between activity levels and cell proliferation, but suggest a strong influence of locomotor activity on cell survival. PMID:24339155

  4. A new view of insect-crustacean relationships I. Inferences from neural cladistics and comparative neuroanatomy.

    Science.gov (United States)

    Strausfeld, Nicholas J; Andrew, David R

    2011-05-01

    Traditional hypotheses regarding the relationships of the major arthropod lineages focus on suites of comparable characters, often those that address features of the exoskeleton. However, because of the enormous morphological variety among arthropods, external characters may lead to ambiguities of interpretation and definition, particularly when species have undergone evolutionary simplification and reversal. Here we present the results of a cladistic analysis using morphological characters associated with brains and central nervous systems, based on the evidence that cerebral organization is generally robust over geological time. Well-resolved, strongly supported phylogenies were obtained from a neuromorphological character set representing a variety of discrete neuroanatomical traits. Phylogenetic hypotheses from this analysis support many accepted relationships, including monophyletic Chelicerata, Myriapoda, and Hexapoda, paraphyletic Crustacea and the union of Hexapoda and Crustacea (Tetraconata). They also support Mandibulata (Myriapoda + Tetraconata). One problematic result, which can be explained by symplesiomorphies that are likely to have evolved in deep time, is the inability to resolve Onychophora as a taxon distinct from Arthropoda. Crucially, neuronal cladistics supports the heterodox conclusion that both Hexapoda and Malacostraca are derived from a common ancestor that possessed a suite of discrete neural centers comprising an elaborate brain. Remipedes and copepods, both resolved as basal to Branchiopoda share a neural ground pattern with Malacostraca. These findings distinguish Hexapoda (Insecta) from Branchiopoda, which is the sister group of the clade Malacostraca + Hexapoda. The present study resolves branchiopod crustaceans as descendents of an ancestor with a complex brain, which means that they have evolved secondary simplification and the loss or reduction of numerous neural systems. PMID:21333750

  5. Fine structure and optical properties of biological polarizers in crustaceans and cephalopods

    Science.gov (United States)

    Chiou, Tsyr-Huei; Caldwell, Roy L.; Hanlon, Roger T.; Cronin, Thomas W.

    2008-04-01

    The lighting of the underwater environment is constantly changing due to attenuation by water, scattering by suspended particles, as well as the refraction and reflection caused by the surface waves. These factors pose a great challenge for marine animals which communicate through visual signals, especially those based on color. To escape this problem, certain cephalopod mollusks and stomatopod crustaceans utilize the polarization properties of light. While the mechanisms behind the polarization vision of these two animal groups are similar, several distinctive types of polarizers (i.e. the structure producing the signal) have been found in these animals. To gain a better knowledge of how these polarizers function, we studied the relationships between fine structures and optical properties of four types of polarizers found in cephalopods and stomatopods. Although all the polarizers share a somewhat similar spectral range, around 450- 550 nm, the reflectance properties of the signals and the mechanisms used to produce them have dramatic differences. In cephalopods, stack-plates polarizers produce the polarization patterns found on the arms and around their eyes. In stomatopods, we have found one type of beam-splitting polarizer based on photonic structures and two absorptive polarizer types based on dichroic molecules. These stomatopod polarizers may be found on various appendages, and on the cuticle covering dorsal or lateral sides of the animal. Since the efficiencies of all these polarizer types are somewhat sensitive to the change of illumination and viewing angle, how these animals compensate with different behaviors or fine structural features of the polarizer also varies.

  6. Organochlorinated contaminants in decapod crustaceans from the coasts of Brittany and Normandy (France).

    Science.gov (United States)

    Bodin, N; Abarnou, A; Le Guellec, A-M; Loizeau, V; Philippon, X

    2007-04-01

    The contamination and distribution of organochlorinated compounds were considered in three crustacean species (edible crab, Cancer pagurus; spider crab, Maja brachydactyla; velvet swimming crab, Necora puber) from five sites along the coasts of Brittany and Normandy (Western and North-Western France). PCBs (16 single congeners), pp'-DDE and HCB were measured in hepatopancreas, gonads and muscle: in all, 175 samples were analysed. The spider crab was the only species found in the five sampling sites, thus enabling comparison between areas. Specimens from Antifer were much more contaminated (summation operator 16 PCBs in hepatopancreas=2000-4000 ng g(-1) dry weight) than those from other sites (50-1000 ng g(-1) d.w.). Among all the three species, the spider crab appeared more contaminated by PCBs than the edible crab, by a factor 2-3, probably in relation with specific differences in their life cycle. There was no difference due to the gender of the species. Within the different analysed tissues, contamination levels increased from muscle to gonads and hepatopancreas in relation with the fat content. A very similar PCB composition was observed in all samples, PCB fingerprints being characterised by the relative importance of the more persistent PCB congeners: CB153, 138, 180, 187, and 118. Finally, these results were compared to recent food regulations first of maximum marker PCB intake and secondly of maximum dioxin-like PCB intake. By considering the muscle, all samples were far below the regulatory limits; for hepatopancreas and gonads, however, some samples were unfit for human consumption. PMID:17223177

  7. Response of rotifer functional groups to changing trophic state and crustacean community

    Directory of Open Access Journals (Sweden)

    Marina MANCA

    2011-08-01

    Full Text Available Information based on taxon-based indices is species-specific while information gained from function-based research can give a comprehensive view of ecosystem processes. We applied the guild-ratio, an index based on the proportion of functional groups of rotifers (i.e. microphagous and raptorial species, on a long-term data set of Lago Maggiore. By applying seasonal trend decomposition based on smoothing techniques and non-metrical multidimensional scaling, we assessed the response of rotifer functional groups to changes in trophic state and climate. While the taxon-based indices showed smooth changes, the function-based index showed a dramatic shift from a raptorial to a microphagous dominance, with a back-shift to raptorial dominance starting in 2000. The seasonal peak of microphagous and raptorial dry weight was clearly separated in the pre-eutrophication period. When mesotrophic conditions prevailed both peaks overlapped, only to be separated again with re-oligotrophication. We attributed these alterations of rotifer functional groups to changes in competition with crustacean zooplankton and to decreased phytoplankton algal abundance and size while altered seasonality in functional groups could be related to inter-group competition for food. We hypothesise that the effects of trophic state (i.e. altered phytoplankton and climate (i.e. altered cladoceran community were transferred across trophic levels to rotifer functional groups. Our study highlights that functional groups are valid instruments for illustrating unifying principles in ecology through a better understanding of ecosystem processes and the interrelationship between trophic levels.

  8. Genome anatomy of the gastrointestinal pathogen, Vibrio parahaemolyticus of crustacean origin.

    Science.gov (United States)

    Tiruvayipati, Suma; Bhassu, Subha; Kumar, Narender; Baddam, Ramani; Shaik, Sabiha; Gurindapalli, Anil Kumar; Thong, Kwai Lin; Ahmed, Niyaz

    2013-01-01

    Vibrio parahaemolyticus, an important human pathogen, is associated with gastroenteritis and transmitted through partially cooked seafood. It has become a major concern in the production and trade of marine food products. The prevalence of potentially virulent and pathogenic V. parahaemolyticus in raw seafood is of public health significance. Here we describe the genome sequence of a V. parahaemolyticus isolate of crustacean origin which was cultured from prawns in 2008 in Selangor, Malaysia (isolate PCV08-7). The next generation sequencing and analysis revealed that the genome of isolate PCV08-7 has closest similarity to that of V. parahaemolyticus RIMD2210633. However, there are certain unique features of the PCV08-7 genome such as the absence of TDH-related hemolysin (TRH), and the presence of HU-alpha insertion. The genome of isolate PCV08-7 encodes a thermostable direct hemolysin (TDH), an important virulence factor that classifies PCV08-7 isolate to be a serovariant of O3:K6 strain. Apart from these, we observed that there is certain pattern of genetic rearrangements that makes V. parahaemolyticus PCV08-7 a non-pandemic clone. We present detailed genome statistics and important genetic features of this bacterium and discuss how its survival, adaptation and virulence in marine and terrestrial hosts can be understood through the genomic blueprint and that the availability of genome sequence entailing this important Malaysian isolate would likely enhance our understanding of the epidemiology, evolution and transmission of foodborne Vibrios in Malaysia and elsewhere. PMID:24330647

  9. Exoskeleton anchoring to tendon cells and muscles in molting isopod crustaceans

    Directory of Open Access Journals (Sweden)

    Nada Žnidaršič

    2012-03-01

    Full Text Available Specialized mechanical connection between exoskeleton and underlying muscles in arthropods is a complex network of interconnected matrix constituents, junctions and associated cytoskeletal elements, which provides prominent mechanical attachment of the epidermis to the cuticle and transmits muscle tensions to the exoskeleton. This linkage involves anchoring of the complex extracellular matrix composing the cuticle to the apical membrane of tendon cells and linking of tendon cells to muscles basally. The ultrastructural arhitecture of these attachment complexes during molting is an important issue in relation to integument integrity maintenance in the course of cuticle replacement and in relation to movement ability. The aim of this work was to determine the ultrastructural organization of exoskeleton – muscles attachment complexes in the molting terrestrial isopod crustaceans, in the stage when integumental epithelium is covered by both, the newly forming cuticle and the old detached cuticle. We show that the old exoskeleton is extensively mechanically connected to the underlying epithelium in the regions of muscle attachment sites by massive arrays of fibers in adult premolt Ligia italica and in prehatching embryos and premolt marsupial mancas of Porcellio scaber. Fibers expand from the tendon cells, traverse the new cuticle and ecdysal space and protrude into the distal layers of the detached cuticle. They likely serve as final anchoring sites before exuviation and may be involved in animal movements in this stage. Tendon cells in the prehatching embryo and in marsupial mancas display a substantial apicobasally oriented transcellular arrays of microtubules, evidently engaged in myotendinous junctions and in apical anchoring of the cuticular matrix. The structural framework of musculoskeletal linkage is basically established in described intramarsupial developmental stages, suggesting its involvement in animal motility within the marsupium.

  10. Conservation Lands and Preserves, Private - Conservation Wells

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The conservation well layer identifies the permitted surface location of oil and gas conservation wells that have not been plugged. These include active, regulatory...

  11. BROAD PHONEME CLASSIFICATION USING SIGNAL BASED FEATURES

    Directory of Open Access Journals (Sweden)

    Deekshitha G

    2014-12-01

    Full Text Available Speech is the most efficient and popular means of human communication Speech is produced as a sequence of phonemes. Phoneme recognition is the first step performed by automatic speech recognition system. The state-of-the-art recognizers use mel-frequency cepstral coefficients (MFCC features derived through short time analysis, for which the recognition accuracy is limited. Instead of this, here broad phoneme classification is achieved using features derived directly from the speech at the signal level itself. Broad phoneme classes include vowels, nasals, fricatives, stops, approximants and silence. The features identified useful for broad phoneme classification are voiced/unvoiced decision, zero crossing rate (ZCR, short time energy, most dominant frequency, energy in most dominant frequency, spectral flatness measure and first three formants. Features derived from short time frames of training speech are used to train a multilayer feedforward neural network based classifier with manually marked class label as output and classification accuracy is then tested. Later this broad phoneme classifier is used for broad syllable structure prediction which is useful for applications such as automatic speech recognition and automatic language identification.

  12. Giant Broad Line Regions in Dwarf Seyferts

    CERN Document Server

    Devereux, Nick

    2015-01-01

    High angular resolution spectroscopy obtained with the Hubble Space Telescope (HST) has revealed a remarkable population of galaxies hosting dwarf Seyfert nuclei with an unusually large broad-line region (BLR). These objects are remarkable for two reasons. Firstly, the size of the BLR can, in some cases, rival those seen in the most luminous quasars. Secondly, the size of the BLR is not correlated with the central continuum luminosity, an observation that distinguishes them from their reverberating counterparts. Collectively, these early results suggest that non-reverberating dwarf Seyferts are a heterogeneous group and not simply scaled versions of each other. Careful inspection reveals broad H Balmer emission lines with single peaks, double peaks, and a combination of the two, suggesting that the broad emission lines are produced in kinematically distinct regions centered on the black hole (BH). Because the gravitational field strength is already known for these objects, by virtue of knowing their BH mass, ...

  13. An androgenic gland membrane-anchored gene associated with the crustacean insulin-like androgenic gland hormone.

    Science.gov (United States)

    Rosen, Ohad; Manor, Rivka; Weil, Simy; Aflalo, Eliahu D; Bakhrat, Anna; Abdu, Uri; Sagi, Amir

    2013-06-01

    Crustacean male sexual differentiation is governed by the androgenic gland (AG) and specifically by the secreted insulin-like AG hormone (IAG), thus far identified in several decapod species including the Australian red claw crayfish Cherax quadricarinatus (termed Cq-IAG). While a few insulin-like AG genes have been identified in crustaceans, other AG-specific genes have not been documented until now. In the present study, we describe the recent identification of a non-IAG AG-specific transcript obtained from the C. quadricarinatus AG cDNA library. This transcript, termed C. quadricarinatus membrane-anchored AG-specific factor (Cq-MAG), was fully sequenced and found to encode a putative product of 189 amino acids including a signal anchoring peptide. Expression of a recombinant GFP fusion protein lacking the signal anchor encoding sequence dramatically affected recombinant protein localization pattern. While the expression of the deleterious fusion protein was observed throughout most of the cell, the native GFP::Cq-MAG fusion protein was observed mainly surrounding the periphery of the nucleus, demonstrating an endoplasmic reticulum (ER)-like localization pattern. Moreover, co-expression of the wild-type Cq-MAG (fused to GFP) and the Cq-IAG hormone revealed that these peptides indeed co-localize. This study is the first to report a protein specifically associated with the insulin-like AG hormone in addition to the finding of another AG-specific transcript in crustaceans. Previous knowledge suggests that insulin/insulin-like factor secretion involves tissue-specific transcripts and membrane-anchored proteins. In this regard, Cq-MAG's tissue specificity, anchoring properties and intracellular co-localization with Cq-IAG suggest that it may play a role in the processing and secretion of this insulin-like AG hormone. PMID:23470660

  14. Single and multi-gene phylogeny of Hepatospora (Microsporidia) - a generalist pathogen of farmed and wild crustacean hosts.

    Science.gov (United States)

    Bateman, K S; Wiredu-Boakye, D; Kerr, R; Williams, B A P; Stentiford, G D

    2016-07-01

    Almost half of all known microsporidian taxa infect aquatic animals. Of these, many cause disease in arthropods. Hepatospora, a recently erected genus, infects epithelial cells of the hepatopancreas of wild and farmed decapod crustaceans. We isolated Hepatospora spp. from three different crustacean hosts, inhabiting different habitats and niches; marine edible crab (Cancer pagurus), estuarine and freshwater Chinese mitten crab (Eriocheir sinensis) and the marine mussel symbiont pea crab (Pinnotheres pisum). Isolates were initially compared using histology and electron microscopy revealing variation in size, polar filament arrangement and nuclear development. However, sequence analysis of the partial SSU rDNA gene could not distinguish between the isolates (~99% similarity). In an attempt to resolve the relationship between Hepatospora isolated from E. sinensis and C. pagurus, six additional gene sequences were mined from on-going unpublished genome projects (RNA polymerase, arginyl tRNA synthetase, prolyl tRNA synthetase, chitin synthase, beta tubulin and heat shock protein 70). Primers were designed based on the above gene sequences to analyse Hepatospora isolated from pea crab. Despite application of gene sequences to concatenated phylogenies, we were unable to discriminate Hepatospora isolates obtained from these hosts and concluded that they likely represent a single species or, at least subspecies thereof. In this instance, concatenated phylogenetic analysis supported the SSU-based phylogeny, and further, demonstrated that microsporidian taxonomies based upon morphology alone are unreliable, even at the level of the species. Our data, together with description of H. eriocheir in Asian crab farms, reveal a preponderance for microvariants of this parasite to infect the gut of a wide array of decapods crustacean hosts and the potential for Hepatospora to exist as a cline across wide geographies and habitats. PMID:27001103

  15. BIODIVERSITY AND BIOGEOGRAPHY OF FRESHWATER CRUSTACEANS (DECAPODA: NATANTIA FROM VANUATU, A COMPARISON WITH FIJI AND NEW CALEDONIA.

    Directory of Open Access Journals (Sweden)

    MARQUET G.

    2002-01-01

    Full Text Available This is the first comprehensive study of freshwater decapoda crustaceans from Vanuatu. Of the nineteen species collected during this study, eighteen appear to be new records for the archipelago. However none of these species is endemic to Vanuatu, nine having a Pacific distribution and ten an Indo-Pacific distribution. Half of the species recorded were widely distributed in Vanuatu, whereas the others were more restricted. A comparison is made with the freshwater decapoda fauna of the two neighbouring archipelagoes namely, those of Fiji and New Caledonia, which have already been thoroughly surveyed.

  16. Narrow and broad senses on salinity scale

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The narrow sense and applicable limit of Practical Salinity Scale 1978 (PSS78) and volumetric titration using silver nitrate to measure the salinity of non-conservative oceanwater are discussed.The salinity obtained by electrical conductivity method and chlorinity salinity method obviously deviates from the absolute salinity (SA). The Density Salinity Scale (DSS98) proposed by the writers can be extensively used in conservative and non-conservative water samples.The merits of the density salinity scale are as follows,(1) The Density Salinity Scale is only related to seawater mass and its buoyant effect, and is not influenced by the variation in seawater composition, and therefore, has high reliability, and repeatability for salinity determination.(2) The salinity values measured by the DSS98 have a conservative property. For oceanwater samples the salinity values are the same as those determined by the PSS78; for non-conservative water samples (e.g. samples from industrial sources), the salinity values are close to the absolute salinity values in comparison with those measured by the PSS78 and the Knudsen method.(3)For a solution with given solute mass, the solution concentration can be converted into the corresponding salinity by the Density Salinity Scale using the expansion coefficient of the solution and the calibration coefficient of the partial molar volume of the solute.

  17. Plasma Redshift in the Broad Line Region

    CERN Document Server

    Hansen, Peter M

    2013-01-01

    Astronomical properties of the broad line emission region (BLR) of active galactic nuclei (AGN) and quasi-stellar objects (QSO) are used to formulate a model of dynamic and electromagnetic scattering characteristics. The results of this modeling show that the observed redshift of these objects may be more complex than that from recession alone due to ionization or plasma effects.

  18. Broad resonances and beta-decay

    DEFF Research Database (Denmark)

    Riisager, K.; Fynbo, H. O. U.; Hyldegaard, S.;

    2015-01-01

    Beta-decay into broad resonances gives a distorted lineshape in the observed energy spectrum. Part of the distortion arises from the phase space factor, but we show that the beta-decay matrix element may also contribute. Based on a schematic model for p-wave continuum neutron states it is argued...

  19. Comparative cation dependency of sugar transport by crustacean hepatopancreas and intestine

    Directory of Open Access Journals (Sweden)

    Ada Duka

    2014-06-01

    Full Text Available Glucose is transported in crustacean hepatopancreas and intestine by Na+-dependent co-transport, while Na+-dependent D-fructose influx has only been described for the hepatopancreas. It is still unclear if the two sugars are independently transported by two distinct cation-dependent co-transporter carrier systems. In this study, lobster (Homarus americanus hepatopancreas brush border membrane vesicles (BBMV were used to characterize, in detail, the cation-dependency of both D-[3H]-glucose and D-[3H]-fructose influxes, while in vitro perfused intestines were employed to determine the nature of cation-dependent sugar transport across this organ. Over the sodium concentration range of 0–100 mM, both [3H]-glucose and [3H]-fructose influxes (0.1 mM; 1 min uptakes by hepatopancreatic BBMV were hyperbolic functions of [Na+]. [3H]-glucose and [3H]-fructose influxes by hepatopancreatic BBMV over a potassium concentration range of 15–100 mM were hyperbolic functions of [K+]. Both sugars displayed significant (p<0.01 Na+/K+-dependent and cation-independent uptake processes. Transepithelial 25 µM [3H]-glucose and [3H]-fructose fluxes across lobster intestine over luminal sodium and potassium concentration ranges of 0–50 mM and 5–100 mM, respectively, were hyperbolic functions of luminal [Na+] and [K+]. As with hepatopancreatic sugar transport, transepithelial intestinal sugar transport exhibited both significant (p<0.01 Na+/K+-dependent and cation-independent processes. Results suggest that both D-glucose and D-fructose are transported by a single SGLT-type carrier in each organ with sodium being the “preferred”, high affinity, cation for both sugars in the hepatopancreas, and potassium being the “preferred”, high affinity, cation for both sugars in the intestine.

  20. A review of crustacean sensitivity to high amplitude underwater noise: Data needs for effective risk assessment in relation to UK commercial species.

    Science.gov (United States)

    Edmonds, Nathan J; Firmin, Christopher J; Goldsmith, Denise; Faulkner, Rebecca C; Wood, Daniel T

    2016-07-15

    High amplitude anthropogenic noise is associated with adverse impacts among a variety of organisms but detailed species-specific knowledge is lacking in relation to effects upon crustaceans. Brown crab (Cancer pagurus), European lobster (Homarus gammarus) and Norway lobster (Nephrops norvegicus) together represent the most valuable commercial fishery in the UK (Defra, 2014). Critical evaluation of literature reveals physiological sensitivity to underwater noise among N. norvegicus and closely related crustacean species, including juvenile stages. Current evidence supports physiological sensitivity to local, particle motion effects of sound production in particular. Derivation of correlative relationships between the introduction of high amplitude impulsive noise and crustacean distribution/abundance is hindered by the coarse resolution of available data at the present time. Future priorities for research are identified and argument for enhanced monitoring under current legislative frameworks outlined. PMID:27210557

  1. Experimental whole-lake increase of dissolved organic carbon concentration produces unexpected increase in crustacean zooplankton density.

    Science.gov (United States)

    Kelly, Patrick T; Craig, Nicola; Solomon, Christopher T; Weidel, Brian C; Zwart, Jacob A; Jones, Stuart E

    2016-08-01

    The observed pattern of lake browning, or increased terrestrial dissolved organic carbon (DOC) concentration, across the northern hemisphere has amplified the importance of understanding how consumer productivity varies with DOC concentration. Results from comparative studies suggest these increased DOC concentrations may reduce crustacean zooplankton productivity due to reductions in resource quality and volume of suitable habitat. Although these spatial comparisons provide an expectation for the response of zooplankton productivity as DOC concentration increases, we still have an incomplete understanding of how zooplankton respond to temporal increases in DOC concentration within a single system. As such, we used a whole-lake manipulation, in which DOC concentration was increased from 8 to 11 mg L(-1) in one basin of a manipulated lake, to test the hypothesis that crustacean zooplankton production should subsequently decrease. In contrast to the spatially derived expectation of sharp DOC-mediated decline, we observed a small increase in zooplankton densities in response to our experimental increase in DOC concentration of the treatment basin. This was due to significant increases in gross primary production and resource quality (lower seston carbon-to-phosphorus ratio; C:P). These results demonstrate that temporal changes in lake characteristics due to increased DOC may impact zooplankton in ways that differ from those observed in spatial surveys. We also identified significant interannual variability across our study region, which highlights potential difficulty in detecting temporal responses of organism abundances to gradual environmental change (e.g., browning). PMID:26919470

  2. Suitability of the clonal marbled crayfish for biogerontological research: a review and perspective, with remarks on some further crustaceans.

    Science.gov (United States)

    Vogt, Günter

    2010-12-01

    This article examines the suitability of the parthenogenetic marbled crayfish for research on ageing and longevity. The marbled crayfish is an emerging laboratory model for development, epigenetics and toxicology that produces up to 400 genetically identical siblings per batch. It is easily cultured, has an adult size of 4-9 cm, a generation time of 6-7 months and a life span of 2-3 years. Experimental data and biological peculiarities like isogenicity, direct development, indeterminate growth, high regeneration capacity and negligible senescence suggest that the marbled crayfish is particularly suitable to investigate the dependency of ageing and longevity from non-genetic factors such as stochastic developmental variation, allocation of metabolic resources, damage and repair, caloric restriction and social stress. It is also well applicable to examine alterations of the epigenetic code with increasing age and to identify mechanisms that keep stem cells active until old age. As a representative of the sparsely investigated crustaceans and of animals with indeterminate growth and extended brood care the marbled crayfish may even contribute to evolutionary theories of ageing and longevity. Some relatives are recommended as substitutes for investigation of topics, for which the marbled crayfish is less suitable like genetics of ageing and achievement of life spans of decades under conditions of low food and low temperature. Research on ageing in the marbled crayfish and its relatives is of practical relevance for crustacean fisheries and aquaculture and may offer starting points for the development of novel anti-ageing interventions in humans. PMID:20582627

  3. Seasonal and Spatial Patterns of an Epibenthic Decapod Crustacean Assemblage in North-west Atlantic Continental Shelf Waters

    Science.gov (United States)

    Viscido, S. V.; Stearns, D. E.; Able, K. W.

    1997-09-01

    To examine seasonal and spatial patterns in a mobile marine assemblage, monthly samples were taken in triplicate with a 2-m beam trawl (6-mm mesh) at three separate stations (landward of the ridge, on the ridge top, and seaward of the ridge). The assemblage was of epibenthic decapod crustaceans, and was situated at a north-west Atlantic continental shelf, sandy ridge site. The assemblage was composed of nine species and was extremely variable over time and space. The sevenspine bay shrimp (Crangon septemspinosa), the Atlantic rock crab (Cancer irroratus), the spider crab (Libinia emarginata) and the lady crab (Ovalipes ocellatus) were the numerical dominants, comprising >98% of all decapods collected. Three of these species (C. septemspinosa,C. irroratus,L. emarginata) exhibited marked spatial heterogeneity in abundance, with many fewer found on the ridge top than at either of the other two stations.Ovalipes ocellatuswas not as spatially variable.Crangonshowed two clear peaks, in spring and fall, as didLibinia, but neither appeared to use the site as a nursery area.Ovalipes ocellatusandC. irroratuseach showed a single peak of very small individuals in the summer and appeared to use this site for settlement. Komolgorov-Smirnov tests, analysis of variance and cluster analysis showed much less difference in assemblage structure between the landward and seaward stations than was demonstrated between either station and the ridge top. The presence of the sand ridge had a clear impact on the abundance and distribution of local decapod crustacean populations.

  4. Fatty acid patterns of Southern Ocean shelf and deep sea peracarid crustaceans and a possible food source, foraminiferans

    Science.gov (United States)

    Würzberg, Laura; Peters, Janna; Brandt, Angelika

    2011-10-01

    In order to investigate the diversity of diet composition in macrobenthic peracarid crustaceans from the Antarctic shelf and deep sea, the fatty acid (FA) composition of different species belonging to the orders Isopoda, Amphipoda, Cumacea and Tanaidacea was analysed. Multivariate analyses of the FA composition confirmed general differences between the orders, but also distinct differences within these orders. To gain information on the origin of the FAs found, the potential food sources sediment, POM and foraminiferans were included in the study. Most of the analysed amphipod species displayed high 18:1( n-9)-18:1( n-7) ratios, widely used as an indicator for a carnivorous component in the diet. Cumaceans were characterised by increased phytoplankton FA markers such as 20:5( n-3) (up to 29% of total FAs), suggesting a diet based on phytodetritus. High values of the FA 20:4( n-6) were found in some munnopsid isopods (up to 21% of total FAs) and some tanaidacean species (up to 19% of total FAs). 20:4( n-6) also occurred in high proportions in some foraminiferan samples (up to 21% of total fatty acids), but not in sediment and POM, possibly indicating the ingestion of foraminiferans by some peracarid crustaceans.

  5. Experimental whole-lake increase of dissolved organic carbon concentration produces unexpected increase in crustacean zooplankton density

    Science.gov (United States)

    Kelly, Patrick T.; Craig, Nicola; Solomon, Christopher T.; Weidel, Brian C.; Zwart, Jacob A.; Jones, Stuart E.

    2016-01-01

    The observed pattern of lake browning, or increased terrestrial dissolved organic carbon (DOC) concentration, across the northern hemisphere has amplified the importance of understanding how consumer productivity varies with DOC concentration. Results from comparative studies suggest these increased DOC concentrations may reduce crustacean zooplankton productivity due to reductions in resource quality and volume of suitable habitat. Although these spatial comparisons provide an expectation for the response of zooplankton productivity as DOC concentration increases, we still have an incomplete understanding of how zooplankton respond to temporal increases in DOC concentration within a single system. As such, we used a whole-lake manipulation, in which DOC concentration was increased from 8 to 11 mg L−1 in one basin of a manipulated lake, to test the hypothesis that crustacean zooplankton production should subsequently decrease. In contrast to the spatially derived expectation of sharp DOC-mediated decline, we observed a small increase in zooplankton densities in response to our experimental increase in DOC concentration of the treatment basin. This was due to significant increases in gross primary production and resource quality (lower seston carbon-to-phosphorus ratio; C:P). These results demonstrate that temporal changes in lake characteristics due to increased DOC may impact zooplankton in ways that differ from those observed in spatial surveys. We also identified significant interannual variability across our study region, which highlights potential difficulty in detecting temporal responses of organism abundances to gradual environmental change (e.g., browning).

  6. Crustaceans associated with Cnidaria, Bivalvia, Echinoidea and Pisces at São Tomé and Príncipe islands.

    Directory of Open Access Journals (Sweden)

    Wirtz, P.

    2008-01-01

    Full Text Available Symbiotic crustaceans were searched for at sea anemones (Actiniaria, encrusting anemones (Zoantharia, horny coral (Gorgonaria, black coral (Antipatharia, bivalves (Bivalvia, and sea urchins (Echinoidea at São Tomé and Príncipe Islands (Gulf of Guinea, eastern central Atlantic. Sixteen species of crustaceans were found in association with these invertebrate hosts; eleven of them were new records for the area and two species, belonging to the genera Hippolyte and Heteromysis, were new for science. The thalassinid Axiopsis serratifrons was occasionally associated with an undescribed species of gobiid fish.

  7. The Engineering of Optical Conservative Force

    CERN Document Server

    Du, Junjie; Ding, Kun; Du, Guiqiang; Lin, Zhifang; Chan, C T; Ng, Jack

    2015-01-01

    Optical forces have been fruitfully applied in a broad variety of areas that not only span the traditional scientific fields such as physics, chemistry, and biology, but also in more applied fields. It is customary and useful to split the optical force into the (conservative) gradient force and the (non-conservative) scattering and absorption force. These forces are different in attributes. The ability to tailor them will open great potential in fundamental optics and practical applications. Here, we present an analytical and a numerical approach to calculate these forces, and, with these tools, we create a fairly general class of 2D conservative optical force field. In general, particles immersed in an optical force do not obey equilibrium statistical mechanics, making the analysis complicated. With conservative forces, these issues are resolved.

  8. Flow over an Erodible Broad Crested Weir

    Directory of Open Access Journals (Sweden)

    Dr. K. C.Sahu

    2015-01-01

    Full Text Available The overtopping flow of water over an earthen embankment causes erosion of soil from its surfaces and the eroded surface of the embankment acts as a Broad crest weir. But the longitudinal profile of the weir goes on changing with time of erosion. Hence crest height of the weir goes changing in accelerated flow condition. In this paper, the discharge equation for this type of flow situation is established for different types of soils used in the embankment. Then, the experiments have been carried out as the analogous rigid beds of the captured eroded profiles at any time of erosion of the broad crested weir to compare the discharge equation and to study the energy loss in dislodging the soil from the surface of the weir and transporting them down stream.

  9. Broad line regions in Seyfert-1 galaxies

    International Nuclear Information System (INIS)

    To reproduce observed emission profiles of Seyfert galaxies, rotation in an accretion disk has been proposed. In this thesis, the profiles emitted by such an accretion disk are investigated. Detailed comparison with the observed profiles yields that a considerable fraction can be fitted with a power-law function, as predicted by the model. The author analyzes a series of high quality spectra of Seyfert galaxies, obtained with the 2.5m telescope at Las Campanas. He presents detailed analyses of two objects: Mkn335 and Akn120. In both cases, strong evidence is presented for the presence of two separate broad line zones. These zones are identified with an accretion disk and an outflowing wind. The disk contains gas with very high densities and emits predominantly the lower ionization lines. He reports on the discovery of very broad wings beneath the strong forbidden line 5007. (Auth.)

  10. Broad iron lines in Active Galactic Nuclei

    CERN Document Server

    Fabian, A C; Reynolds, C S; Young, A J

    2000-01-01

    An intrinsically narrow line emitted by an accretion disk around a black hole appears broadened and skewed as a result of the Doppler effect and gravitational redshift. The fluorescent iron line in the X-ray band at 6.4-6.9keV is the strongest such line and is seen in the X-ray spectrum of many active galactic nuclei and, in particular, Seyfert galaxies. It is an important diagnostic with which to study the geometry and other properties of the accretion flow very close to the central black hole. The broad iron line indicates the presence of a standard thin accretion disk in those objects, often seen at low inclination. The broad iron line has opened up strong gravitational effects around black holes to observational study with wide-reaching consequences for both astrophysics and physics.

  11. 7 CFR 12.23 - Conservation plans and conservation systems.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Conservation plans and conservation systems. 12.23... CONSERVATION Highly Erodible Land Conservation § 12.23 Conservation plans and conservation systems. (a) Use of field office technical guide. A conservation plan or conservation system developed for the purposes...

  12. Fourier evaluation of broad Moessbauer spectra

    International Nuclear Information System (INIS)

    It is shown by the Fourier analysis of broad Moessbauer spectra that the even part of the distribution of the dominant hyperfine interaction (hyperfine field or quadrupole splitting) can be obtained directly without using least-square fitting procedures. Also the odd part of this distribution correlated with other hyperfine parameters (e.g. isomer shift) can be directly determined. Examples for amorphous magnetic and paramagnetic iron-based alloys are presented. (author)

  13. A Broad View of Macroeconomic Stability

    OpenAIRE

    José Antonio Ocampo

    2005-01-01

    This paper recommends a broad concept of macroeconomic stability, whereby “sound macroeconomic frameworks” include not only price stability and sound fiscal policies, but also a well-functioning real economy, sustainable debt ratios and healthy public and private sector balance sheets. These multiple dimensions imply using multiple policy instruments. The paper elaborates a framework for developing countries that involves active use of counter-cyclical macroeconomic policies (exchange rate, m...

  14. Crx broadly modulates the pineal transcriptome

    OpenAIRE

    Rovsing, Louise; Clokie, Samuel; Bustos, Diego M.; Rohde, Kristian; Steven L Coon; Litman, Thomas; Rath, Martin F.; Møller, Morten; Klein, David C.

    2011-01-01

    Cone-rod homeobox (Crx) encodes Crx, a transcription factor expressed selectively in retinal photoreceptors and pinealocytes, the major cell type of the pineal gland. Here, the influence of Crx on the mammalian pineal gland was studied by light and electron microscopy and by use of microarray and qRTPCR technology, thereby extending previous studies on selected genes (Furukawa et al. 1999). Deletion of Crx was not found to alter pineal morphology, but was found to broadly modulate the mouse p...

  15. Relativistic redshifts in quasar broad lines

    International Nuclear Information System (INIS)

    The broad emission lines commonly seen in quasar spectra have velocity widths of a few percent of the speed of light, so special- and general-relativistic effects have a significant influence on the line profile. We have determined the redshift of the broad Hβ line in the quasar rest frame (determined from the core component of the [O III] line) for over 20,000 quasars from the Sloan Digital Sky Survey Data Release 7 quasar catalog. The mean redshift as a function of line width is approximately consistent with the relativistic redshift that is expected if the line originates in a randomly oriented Keplerian disk that is obscured when the inclination of the disk to the line of sight exceeds ∼30°-45°, consistent with simple active galactic nucleus unification schemes. This result also implies that the net line-of-sight inflow/outflow velocities in the broad-line region are much less than the Keplerian velocity when averaged over a large sample of quasars with a given line width.

  16. Relativistic redshifts in quasar broad lines

    CERN Document Server

    Tremaine, Scott; Liu, Xin; Loeb, Abraham

    2014-01-01

    The broad emission lines commonly seen in quasar spectra have velocity widths of a few per cent of the speed of light, so special- and general-relativistic effects have a significant influence on the line profile. We have determined the redshift of the broad H-beta line in the quasar rest frame (determined from the core component of the [OIII] line) for over 20,000 quasars from the Sloan Digital Sky Survey DR7 quasar catalog. The mean redshift as a function of line width is approximately consistent with the relativistic redshift that is expected if the line originates in a randomly oriented Keplerian disk that is obscured when the inclination of the disk to the line of sight exceeds ~30-45 degrees, consistent with simple AGN unification schemes. This result also implies that the net line-of-sight inflow/outflow velocities in the broad-line region are much less than the Keplerian velocity when averaged over a large sample of quasars with a given line width.

  17. Identification and Characterization of a Highly Conserved Crenarchaeal Protein Lysine Methyltransferase with Broad Substrate Specificity

    OpenAIRE

    Chu, Yindi; Zhang, Zhenfeng; Wang, Qian; Luo, Yuanming; Huang, Li

    2012-01-01

    Protein lysine methylation occurs extensively in the Crenarchaeota, a major kingdom in the Archaea. However, the enzymes responsible for this type of posttranslational modification have not been found. Here we report the identification and characterization of the first crenarchaeal protein lysine methyltransferase, designated aKMT, from the hyperthermophilic crenarchaeon Sulfolobus islandicus. The enzyme was capable of transferring methyl groups to selected lysine residues in a substrate prot...

  18. Change in Species Diversity during Recovering Process of Evergreen Broad-leaved Fo rest

    Institute of Scientific and Technical Information of China (English)

    WenYuanguang; LiuShirong; ChenFang; HeTatping; LiangHongwen

    2005-01-01

    Evergreen broad-leaved forest is one of the most important vegetation types in China. Because of the human activities, evergreen broad-leaved forest has been destroyed extensively, leading to degraded ecosystem. It is urgent to conserve and restore these natural forests in China.tn this paper, the tendency and rate of species diversity restoration of the evergreen broad-lea ved forest in Darning Mountain has been studied. The main results are as follows:(a) in subtropical mid-mountain area, species diversity in degraded evergreen broad-leaved forest can be restored. Through analyzing b diversity index of communities in different time and space, it was found that the species composition of communities tend to be the same as that in the zonal evergreen broad-leaved forest. (b) The restoration rate of evergreen broad-leaved forest was very fast. Planting Chinese fir after clear-cutting and controlled burning of the forest 178 species appeared in a 60Om2, sample area after 20 years"" natural recovering. Among these species, 58 were tree layer and the height of community reached 18m, The survey suggested that it would take only 20 years for the degraded forest to develop into community composed of light demanding broad-leaved pioneer trees and rain-tolerance broad-leaved trees, and it need another 40-80 years to reach the stage consisting of min-tulerance evergreen broad-leaved trees, (c) Species number increased quickly at the early stage (2-20 years) during vegetation recovering process toward the climax, and decreased at the min-stage (50-60 years ), then maintained a relatively stable level at the late-stage (over 150 years).

  19. Monthly variation in crustacean assemblage (decapod and stomatopod) and its relationships with environmental variables in Laizhou Bay, China

    Science.gov (United States)

    Wu, Qiang; Wang, Jun; Zhang, Bo; Chen, Ruisheng; Jin, Xianshi

    2016-04-01

    In this study, we investigated the community structure of crustaceans (decapod and stomatopod) inhabiting the sandy mud bottoms of Laizhou Bay (northeastern China) monthly from May 2011 to April 2012. Investigation was stopped from December 2011 to February 2012 because of the extreme weather and sea ice. A total of 205,057 specimens belonging to 31 species (shrimp, 15; crab, 15; and stomatopod, 1) were collected in 148 hauls. From 2011 to 2012, Oratosquilla oratoria was the dominant biomass species (47.80%), followed by Charybdis japonica (15.49%), Alpheus japonicas (12.61%), Portunus trituberculatus (6.46%), and Crangon spp. (4.19%). Crangon spp. was the most dominant species by individual (32.55%). O. oratoria was the most-frequently encountered species (81.76%), followed by Palaemon gravieri (70.95%), C. japonica (65.54%), A. japonicas (62.16%), and P. trituberculatus (54.73%). The biomass density increased from August to September 2011 and decreased from March 2012 to April 2012. The dynamics of the ecological indices evolve in a similar manner, with high values of diversity and evenness and rich species from May to June 2011 and low values from September to October 2011. O. oratoria, C. japonica, and P. trituberculatus differed by biomass data between groups I (samples obtained from September to October 2011) and II (samples in other months). These species contributed more than 70% to the similarity of the crustacean community structure. Furthermore, the subsets of environmental variables that best matched the crustacean-assemblage structure were as follows: water depth (WD) in summer (June to August); sea surface temperature (SST), dissolved oxygen (DO), and WD in autumn (September to November); and DO, salinity, and WD in spring (March to May). The calculated correlation coefficients and significance level were higher in the period of July to August 2011 than in other months. Comparing 2011 to 2012 with 1982 to 1983, the species composition remained stable

  20. A Review of Some Basic Parasite Diseases in Culture Fisheries Flagellids, Dinoflagellides and Ichthyophthriasis, Ichtyobodiasis, Coccidiosis Trichodiniasis, Heminthiasis, Hirudinea Infestation, Crustacean Parsite and Ciliates

    OpenAIRE

    J.F.N. Abowei; O.F. Briyai; S.E. Bassey

    2011-01-01

    A review some basic parasite diseases in fish: flagellids, dinoflagellides and ichthyophthriasis in African fish was carried out to educate fish culturist and the private sector on some challenges faced in culture fisheries. Some common parasite diseases: Ichtyobodiasis, Coccidiosis, Ichtyopthiariasis, Trichodiniasis, Heminthiasis, Crustacean parasite, Hirudinea infestation, Flagellates and Ciliates, Taxonomy and diagnosis, Life cycle and biology, Epizootiology, pathology, control, Infections...

  1. Broad spectrum antibiotic compounds and use thereof

    Energy Technology Data Exchange (ETDEWEB)

    Koglin, Alexander; Strieker, Matthias

    2016-07-05

    The discovery of a non-ribosomal peptide synthetase (NRPS) gene cluster in the genome of Clostridium thermocellum that produces a secondary metabolite that is assembled outside of the host membrane is described. Also described is the identification of homologous NRPS gene clusters from several additional microorganisms. The secondary metabolites produced by the NRPS gene clusters exhibit broad spectrum antibiotic activity. Thus, antibiotic compounds produced by the NRPS gene clusters, and analogs thereof, their use for inhibiting bacterial growth, and methods of making the antibiotic compounds are described.

  2. Paradoxes in Biodiversity Conservation

    OpenAIRE

    David Pearce

    2005-01-01

    Biodiversity is important for human wellbeing, but it is declining. Measures to conserve biodiversity are essential but may be a waste of effort if several paradoxes are not addressed. The highest levels of diversity are in nations least able to practise effective conservation. The flow of funds to international biodiversity conservation appears trivial when compared to the scale of biodiversity loss. International agreements may not actually protect or conserve more than what would have been...

  3. Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

    Directory of Open Access Journals (Sweden)

    Chadanat Noonin

    Full Text Available Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS, bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish and Tenebrio molitor larvae (mealworm. The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the

  4. Conservation Action Handbook.

    Science.gov (United States)

    National Rifle Association, Washington, DC.

    Conservation problems are identified, with some suggestions for action. General areas covered are: Wildlife Conservation, Soil Conservation, Clean Water, Air Pollution Action, and Outdoor Recreation Action. Appendices list private organizations or agencies concerned with natural resource use and/or management, congressional committees considering…

  5. Stochastic Conservation Laws?

    CERN Document Server

    Sidharth, B G

    1998-01-01

    We examine conservation laws, typically the conservation of linear momentum, in the light of a recent successful formulation of fermions as Kerr-Newman type Black Holes, which are created fluctuationally from a background Zero Point Field. We conclude that these conservation laws are to be taken in the spirit of thermodynamic laws.

  6. Conservation in Physics.

    Science.gov (United States)

    Finkel, Edward

    1991-01-01

    Discussed is the physical concept of conservation as it is framed within the laws of conservation of mass, of momentum, and of energy. The derivation of Ohm's Law as a generalization of the relationship between the observed measurements of voltage and current serves as the exemplar of how conservation theories are formed. (JJK)

  7. Waterfowl populations of conservation concern: learning from diverse challenges, models, and conservation strategies

    Science.gov (United States)

    Austin, Jane E.; Slattery, Stuart; Clark, Robert G.

    2014-01-01

    There are 30 threatened or endangered species of waterfowl worldwide, and several sub-populations are also threatened. Some of these species occur in North America, and others there are also of conservation concern due to declining population trends and their importance to hunters. Here we review conservation initiatives being undertaken for several of these latter species, along with conservation measures in place in Europe, to seek common themes and approaches that could be useful in developing broad conservation guidelines. While focal species may vary in their life histories, population threats and geopolitical context, most conservation efforts have used a systematic approach to understand factors limiting populations and o identify possible management or policy actions. This approach generally includes a priori identification of plausible hypotheses about population declines or status, incorporation of hypotheses into conceptual or quantitative planning models, and the use of some form of structured decision making and adaptive management to develop and implement conservation actions in the face of many uncertainties. A climate of collaboration among jurisdictions sharing these birds is important to the success of a conservation or management programme. The structured conservation approach exemplified herein provides an opportunity to involve stakeholders at all planning stages, allows for all views to be examined and incorporated into model structures, and yields a format for improved communication, cooperation and learning, which may ultimately be one of the greatest benefits of this strategy.

  8. Exactly conservative integrators

    Energy Technology Data Exchange (ETDEWEB)

    Shadwick, B.A.; Bowman, J.C.; Morrison, P.J.

    1995-07-19

    Traditional numerical discretizations of conservative systems generically yield an artificial secular drift of any nonlinear invariants. In this work we present an explicit nontraditional algorithm that exactly conserves invariants. We illustrate the general method by applying it to the Three-Wave truncation of the Euler equations, the Volterra-Lotka predator-prey model, and the Kepler problem. We discuss our method in the context of symplectic (phase space conserving) integration methods as well as nonsymplectic conservative methods. We comment on the application of our method to general conservative systems.

  9. Exactly conservation integrators

    Energy Technology Data Exchange (ETDEWEB)

    Shadwick, B.A.; Bowman, J.C.; Morrison, P.J. [Univ. of Texas, Austin, TX (United States)

    1999-03-01

    Traditional explicit numerical discretizations of conservative systems generically predict artificial secular drifts of any nonlinear invariants. In this work the authors present a general approach for developing explicit nontraditional algorithms that conserve such invariants exactly. They illustrate the method by applying it to the three-wave truncation of the Euler equations, the Lotka-Volterra predator-prey model, and the Kepler problem. The ideas are discussed in the context of symplectic (phase-space-conserving) integration methods as well as nonsymplectic conservative methods. They comment on the application of the method to general conservative systems.

  10. A broad view of model validation

    International Nuclear Information System (INIS)

    The safety assessment of a nuclear waste repository requires the use of models. Such models need to be validated to ensure, as much as possible, that they are a good representation of the actual processes occurring in the real system. In this paper we attempt to take a broad view by reviewing step by step the modeling process and bringing out the need to validating every step of this process. This model validation includes not only comparison of modeling results with data from selected experiments, but also evaluation of procedures for the construction of conceptual models and calculational models as well as methodologies for studying data and parameter correlation. The need for advancing basic scientific knowledge in related fields, for multiple assessment groups, and for presenting our modeling efforts in open literature to public scrutiny is also emphasized. 16 refs

  11. Buildup factors for broad gamma beams

    International Nuclear Information System (INIS)

    The paper deals with buildup factors for the photon number and the exposure in broad conical beams penetrating through iron slabs. Using the Monte Carlo method, the dependence on the thickness of the slabs is calculated for various geometrical configurations of the 137Cs radiation source, the slab and the detector. The same dependence has also been measured for 137Cs and 60Co. The results show the dependence of the buildup factor B on the collimation angle α (B increases with increasing α), on the distance a between the source and the slab (B increases with increasing a), and on the distance b between the detector and the slab (B decreases with increasing b). Comparison of the obtained results with those from model configurations shows that in the latter case errors may range up to nearly 100%. (author)

  12. Broad-band acoustic hyperbolic metamaterial

    CERN Document Server

    Shen, Chen; Sui, Ni; Wang, Wenqi; Cummer, Steven A; Jing, Yun

    2015-01-01

    Acoustic metamaterials (AMMs) are engineered materials, made from subwavelength structures, that exhibit useful or unusual constitutive properties. There has been intense research interest in AMMs since its first realization in 2000 by Liu et al. A number of functionalities and applications have been proposed and achieved using AMMs. Hyperbolic metamaterials are one of the most important types of metamaterials due to their extreme anisotropy and numerous possible applications, including negative refraction, backward waves, spatial filtering, and subwavelength imaging. Although the importance of acoustic hyperbolic metamaterials (AHMMs) as a tool for achieving full control of acoustic waves is substantial, the realization of a broad-band and truly hyperbolic AMM has not been reported so far. Here, we demonstrate the design and experimental characterization of a broadband AHMM that operates between 1.0 kHz and 2.5 kHz.

  13. Crx broadly modulates the pineal transcriptome

    DEFF Research Database (Denmark)

    Rovsing, Louise; Clokie, Samuel; Bustos, Diego M;

    2011-01-01

    microarray and qRTPCR technology, thereby extending previous studies on selected genes (Furukawa et al. 1999). Deletion of Crx was not found to alter pineal morphology, but was found to broadly modulate the mouse pineal transcriptome, characterized by a > 2-fold down-regulation of 543 genes and a > 2-fold up-regulation...... of 745 genes (p < 0.05). Of these, one of the most highly up-regulated (18-fold) was Hoxc4, a member of the Hox gene family, members of which are known to control gene expression cascades. During a 24-h period, a set of 51 genes exhibited differential day/night expression in pineal glands of wild...... influences differential night/day gene expression in this tissue. Some effects of Crx deletion on the pineal transcriptome might be mediated by Hoxc4 up-regulation....

  14. Magnetohydrodynamic stability of broad line region clouds

    CERN Document Server

    Krause, Martin; Burkert, Andreas

    2012-01-01

    Hydrodynamic stability has been a longstanding issue for the cloud model of the broad line region in active galactic nuclei. We argue that the clouds may be gravitationally bound to the supermassive black hole. If true, stabilisation by thermal pressure alone becomes even more difficult. We further argue that if magnetic fields should be present in such clouds at a level that could affect the stability properties, they need to be strong enough to compete with the radiation pressure on the cloud. This would imply magnetic field values of a few Gauss for a sample of Active Galactic Nuclei we draw from the literature. We then investigate the effect of several magnetic configurations on cloud stability in axi-symmetric magnetohydrodynamic simulations. For a purely azimuthal magnetic field which provides the dominant pressure support, the cloud first gets compressed by the opposing radiative and gravitational forces. The pressure inside the cloud then increases, and it expands vertically. Kelvin-Helmholtz and colu...

  15. Connectivity of neutral networks and structural conservation in protein evolution

    OpenAIRE

    Bastolla, Ugo; Porto, Markus; Roman, H. Eduardo; Vendruscolo, Michele

    2001-01-01

    Protein structures are much more conserved than sequences during evolution. Based on this observation, we investigate the consequences of structural conservation on protein evolution. We study seven of the most studied protein folds, finding out that an extended neutral network in sequence space is associated to each of them. Within our model, neutral evolution leads to a non-Poissonian substitution process, due to the broad distribution of connectivities in neutral networks. The observation ...

  16. Consumer energy conservation policies and programs in the Netherlands

    International Nuclear Information System (INIS)

    This report presents an overview of consumer energy conservation policies and programs in the Netherlands and analyses them in terms of program objectives, conservation strategies, program instruments, context elements, and impacts on energy consumption, on consumers' lifestyles and on the environment. Part 1 briefly outlines the energy situation in the Netherlands. Diversification of energy sources and conservation of energy use are the main themes of Dutch energy policy. Controversial issues are the export volume of natural gas and the acceptability of nuclear energy. Part 2 describes and evaluates a number of consumer energy conservation programs. A broad range of programs is presented, including governmental programs (mass media compaigns, the national insulation program), initiatives from consumer organizations and environmental groups, as well as projects on the community level. Part 3 summarizes the main findings and suggests some policy recommendations. The climate of opinion in the Netherlands appears to be quite favorable towards energy conservation. The commitment to conserve, however, is not very strong. Given the broad variety of conservation programs the necessity of coordination is emphasized. As consumers tend to be weakly represented in the program agencies, it is recommended to extend or introduce their participation. Particular attention is given to the lack of evaluation studies. Usually, program impacts are unknown. The desirability of utilizing community level indicators in the assessment of energy conservation policy is underlined. (orig.)

  17. Neutralization of low energy broad ion beam

    International Nuclear Information System (INIS)

    The paper is devoted to experimental and theoretical investigation of a low energy broad ion beam space charge and current compensation and ion-beam plasma (IBP), which would be created in transport space of the beam. The beam had cylindrical symmetry. The continuous uniform and hole tube like ion beams are used in the experiments. Different channels of electron appearing have been investigated for cases of neutralization due to secondary γ-electrons from the target and by electrons from glow cathode-neutralizer with metal or dielectric target. Results of neutralizing electrons energy distributions function measurements are presented as well as dependences of electron temperature and self-consisted plasma potential vs. beam parameters, ambient gas pressure, neutralizer parameters. Role of the thermoelectrons and dependence of IBP parameters on neutralizer area, location and potential are discussed. Significant role in neutralization of spatial collisional processes has been revealed even in neutralization by thermocathode. On the base of the experimental results self-consistent theoretical model have been developed, which describes the behavior of intense ion beam passing through the neutral gas at low pressure within conductive walls. The collisionless approach is used which means absence of collisional relaxation of the beam. This theory is used to derive the plasma potential and electron temperature within the beam

  18. Econometric modelling of conservation

    International Nuclear Information System (INIS)

    The issue of energy conservation in general, and conservation in the natural gas markets in particular, has recently had a much lower profile than in the past, when energy prices were significantly higher and energy costs composed a much larger proportion of industrial operating costs than today. The recent downward trend in energy prices has diverted attention away from this issue. In the face of expected significant real price increases, increasing pressure from environmental groups, and directives on the part of regulator authorities, conservation is once again becoming a topic of consideration in the energy industry. From the point of view of gas demand forecasting, conservation has received too little attention. The intentions of this paper are to establish the need for forecasting conservation in the natural gas utility sector, and to construct a model of industrial demand which incorporates conservation and is appropriate for use as a forecasting tool

  19. Conservation: Toward firmer ground

    Science.gov (United States)

    1975-01-01

    The following aspects of energy conservation were discussed: conservation history and goals, conservation modes, conservation accounting-criteria, and a method to overcome obstacles. The conservation modes tested fall into one of the following categories: reduced energy consumption, increased efficiency of energy utilization, or substitution of one or more forms of energy for another which is in shorter supply or in some sense thought to be of more value. The conservation accounting criteria include net energy reduction, economic, and technical criteria. A method to overcome obstacles includes (approaches such as: direct personal impact (life style, income, security, aspiration), an element of crisis, large scale involvement of environmental, safety, and health issues, connections to big government, big business, big politics, involvement of known and speculative science and technology, appeal to moral and ethical standards, the transient nature of opportunities to correct the system.

  20. Financing Biodiversity Conservation

    OpenAIRE

    Ricardo Bayón; J. Steven Lovink; Wouter J. Veening

    2000-01-01

    Financing the conservation and sustainable use of biodiversity has been called one of the greatest challenges. At the heart of this challenge lies the low financial and political value which is often assigned to biodiversity and the resulting lack of financial mechanisms for conservation and sustainable use. This report provides an overview of existing and experimental financing mechanisms that can be used to encourage the conservation and sustainable use of biodiversity. To help to better un...

  1. Preliminary study of sperm chromatin characteristics of the brachyuran crab Maja brachydactyla. Histones and nucleosome-like structures in decapod crustacean sperm nuclei previously described without SNBPs.

    Science.gov (United States)

    Kurtz, K; Ausió, J; Chiva, M

    2009-10-01

    An interesting characteristic of decapod crustacean sperm nuclei is that they do not contain highly packaged chromatin. In the present study we re-examine the presence of DNA-interacting proteins in sperm nuclei of the brachyuran Maja brachydactyla. Although previous reports have indicated that, unlike the majority of sperm cells, DNA of decapod sperm is not organized by basic proteins, in this work we show that: (1) histones are present in sperm of M. brachydactyla; (2) histones are associated with sperm DNA; (3) histone H3 appears in lower proportions than the other core histones, while histone H2B appears in higher proportions; and (4) histone H3 in sperm nuclei is acetylated. This work complements a previous study of sperm histones of Cancer pagurus and supports the suggestion that decapod crustacean sperm chromatin deserves further attention. PMID:19324386

  2. Broad spectrum anthelmintic potential of Cassia plants

    Institute of Scientific and Technical Information of China (English)

    Suman Kundu; Saptarshi Roy; Larisha Mawkhleing Lyndem

    2014-01-01

    Objective: To study the in vitro anthelmintic efficacy of Cassia alata (C. alata), Cassia(C. angustifolia) and Cassia occidentalis (C. occidentalis). angustifolia Methods: Crude ethanol extract from leaves of the three plants were prepared in rotary evaporator and different concentrations (10, 20 and 40 mg/mL) of leaf extracts were used for treatment on different representatives of helminthes (Heterakis gallinarum, Raillietina tetragona and Catatropis sp.) from domestic fowl (Gallus gallus domesticus). Loss of motility and death were monitored frequently.Results: C. alata showed early paralysis in all worms treated followed by C. angustifolia. C. occidentalis in combination with C. alata together caused early paralysis in all treated worms than the combination of C. alata with C. angustfolia. While Heterakis gallinarum in control survived for (81.33±2.07) h, treated worms lost their motility at (5.71±0.10) h, (6.60±0.86) h and (13.95±0.43) h with C. angustifolia, C. alata and C. occidentalis respectively at a concentration of 40 mg/mL which showed better efficacy than albendazole. Catatropis sp. survival period was (26.49±1.38) h in control, but with plant treatment, it lost its motility in just (0.57±0.08) h, (1.00±0.12) h and (1.47±0.40) h at 40 mg/mL concentration of C. alata, C. angustifolia and C. occidentalis respectively.Raillietina tetragona on the other hand became paralysed at (1.68±0.27) h, (2.95±0.29) h and (4.13±0.31) h with above concentrations treated with three plants respectively, however in control it survived up to (81.93±4.71) h.Conclusions:This present study indicated broad spectrum vermifugal activity of all plants tested.

  3. Microlensing of Quasar Broad Emission Lines: Constraints on Broad Line Region Size

    CERN Document Server

    Guerras, E; Jimenez-Vicente, J; Kochanek, C S; Muñoz, J A; Falco, E; Motta, V

    2012-01-01

    We measure the differential microlensing of the broad emission lines between 18 quasar image pairs in 16 gravitational lenses. We find that high ionization lines such as CIV are more strongly microlensed than low ionization lines, indicating that the high ionization line emission regions are more compact. If we statistically model the distribution of microlensing magnifications, we obtain estimates for the broad line region radius of 24 (-15/+22) and 55 (-35/+150) light-days (90% confidence) for the high and low ionization lines, respectively. When the sample is divided attending to quasar luminosity, we find that the line emission regions of more luminous quasars are larger, with a slope consistent with the expected scaling from photoionization models. Our estimates also agree well with the results from local reveberation mapping studies.

  4. Validation, automatic generation and use of broad phonetic transcriptions

    NARCIS (Netherlands)

    Bael, Cristophe Patrick Jan Van

    2007-01-01

    Broad phonetic transcriptions represent the pronunciation of words as strings of characters from specifically designed symbol sets. In everyday life, broad phonetic transcriptions are often used as aids to pronounce (foreign) words. In addition, broad phonetic transcriptions are often used for lingu

  5. Structural basis of hepatitis C virus neutralization by broadly neutralizing antibody HCV1

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Leopold; Giang, Erick; Robbins, Justin B.; Stanfield, Robyn L.; Burton, Dennis R.; Wilson, Ian A.; Law, Mansun (Scripps)

    2012-10-29

    Hepatitis C virus (HCV) infects more than 2% of the global population and is a leading cause of liver cirrhosis, hepatocellular carcinoma, and end-stage liver diseases. Circulating HCV is genetically diverse, and therefore a broadly effective vaccine must target conserved T- and B-cell epitopes of the virus. Human mAb HCV1 has broad neutralizing activity against HCV isolates from at least four major genotypes and protects in the chimpanzee model from primary HCV challenge. The antibody targets a conserved antigenic site (residues 412-423) on the virus E2 envelope glycoprotein. Two crystal structures of HCV1 Fab in complex with an epitope peptide at 1.8-{angstrom} resolution reveal that the epitope is a {beta}-hairpin displaying a hydrophilic face and a hydrophobic face on opposing sides of the hairpin. The antibody predominantly interacts with E2 residues Leu{sup 413} and Trp{sup 420} on the hydrophobic face of the epitope, thus providing an explanation for how HCV isolates bearing mutations at Asn{sup 415} on the same binding face escape neutralization by this antibody. The results provide structural information for a neutralizing epitope on the HCV E2 glycoprotein and should help guide rational design of HCV immunogens to elicit similar broadly neutralizing antibodies through vaccination.

  6. Non-target effects of the insecticide methoprene on molting in the estuarine crustacean Neomysis integer (Crustacea: Mysidacea)

    OpenAIRE

    Ghekiere, A.; Verslycke, T.; Fockedey, N.; Janssen, C.R.

    2006-01-01

    Ecdysteroids, the molting hormones in crustaceans and other arthropods, play a crucial role in the control of growth, reproduction and embryogenesis of these organisms. Insecticides are often designed to target specific endocrine-regulated functions such as molting and larval development such as methoprene, a juvenile hormone analogue.The aim of this study was to examine the effects of methoprene on molting in a non-target species, the estuarine mysid Neomysis integer (Crustacea: Mysidacea). ...

  7. The First Venomous Crustacean Revealed by Transcriptomics and Functional Morphology: Remipede Venom Glands Express a Unique Toxin Cocktail Dominated by Enzymes and a Neurotoxin

    OpenAIRE

    Reumont, von; Blanke, Alexander; Richter, Sandy; Alvarez, Fernando; Bleidorn, Christoph; Jenner, Ronald A.

    2013-01-01

    Animal venoms have evolved many times. Venomous species are especially common in three of the four main groups of arthropods (Chelicerata, Myriapoda, and Hexapoda), which together represent tens of thousands of species of venomous spiders, scorpions, centipedes, and hymenopterans. Surprisingly, despite their great diversity of body plans, there is no unambiguous evidence that any crustacean is venomous. We provide the first conclusive evidence that the aquatic, blind, and cave-dwelling remipe...

  8. Temporal and spatial changes of crustaceans in mixed eelgrass beds, Zostera marina L. and Z. noltii Hornem., at the Sinop peninsula coast (the southern Black Sea, Turkey)

    OpenAIRE

    KARAÇUHA, Melek ERSOY; SEZGİN, M.; DAĞLI, Ertan

    2009-01-01

    This research was carried out to determine the macrobenthic crustacean species associated with mixed eelgrass beds (Zostera marina and Z. noltii) occurring in the upper-infralittoral zone of the Sinop peninsula coast (the southern Black Sea, Turkey) and their bioecolological features. From June 2004 to April 2005, investigations were seasonally performed at the depths of 2-4 m at 6 different stations chosen on the Sinop peninsula coast. As a result of the study, a total of 7057 individuals be...

  9. Long-term responses of sandy beach crustaceans to the effects of coastal armouring after the 2010 Maule earthquake in South Central Chile

    Science.gov (United States)

    Rodil, Iván F.; Jaramillo, Eduardo; Acuña, Emilio; Manzano, Mario; Velasquez, Carlos

    2016-02-01

    Earthquakes and tsunamis are large physical disturbances frequently striking the coast of Chile with dramatic effects on intertidal habitats. Armouring structures built as societal responses to beach erosion and shoreline retreat are also responsible of coastal squeeze and habitat loss. The ecological implications of interactions between coastal armouring and earthquakes have recently started to be studied for beach ecosystems. How long interactive impacts persist is still unclear because monitoring after disturbance generally extends for a few months. During five years after the Maule earthquake (South Central Chile, February 27th 2010) we monitored the variability in population abundances of the most common crustacean inhabitants of different beach zones (i.e. upper, medium, and lower intertidal) at two armoured (one concrete seawall and one rocky revetment) and one unarmoured sites along the sandy beach of Llico. Beach morphology changed after the earthquake-mediated uplift, restoring upper- and mid-shore armoured levels that were rapidly colonized by typical crustacean species. However, post-earthquake increasing human activities affected the colonization process of sandy beach crustaceans in front of the seawall. Lower-shore crab Emerita analoga was the less affected by armouring structures, and it was the only crustacean species present at the three sites before and after the earthquake. This study shows that field sampling carried out promptly after major disturbances, and monitoring of the affected sites long after the disturbance is gone are effective approaches to increase the knowledge on the interactive effects of large-scale natural phenomena and artificial defences on beach ecology.

  10. Metabotropic glutamate receptor agonists modify the pyloric output of the crustacean stomatogastric ganglion.

    Science.gov (United States)

    Pérez-Acevedo, Nivia L; Krenz, Wulf D

    2005-11-16

    We have studied the effects of groups I, II, and III metabotropic glutamate receptor (mGluR) agonists and antagonists on pyloric activity in the stomatogastric ganglion (STG) of the Caribbean spiny lobster Panulirus argus. We have found that agonists for all three groups of mGluRs modify the pyloric output. The group I agonist, l-quisqualic acid (l-QA), activated the pyloric central pattern generator (CPG). When the pyloric rhythm was partially suppressed by sucrose-block of input fibers in the stomatogastric nerve (stn), l-QA accelerated the rhythmic activity. In addition, the number of spike discharges was increased in pyloric motoneurons: pyloric (PY), and lateral pyloric (LP). In completely blocked preparations, a slow pyloric rhythm was initiated by l-QA. Groups II and III agonists exerted an inhibitory effect on pyloric activity. The group II agonist, (2S,1'S,2'S)-2-(Carboxycyclopropyl)glycine (L-CCG-I), decreased both the frequency of the pyloric rhythm and the number of spike discharges in the motoneurons: ventricular dilator (VD), PY, and LP. The effects of L-CCG-I were dose-dependent. The group III agonist, l-(+)-2-Amino-4-phosphonobutyric acid (l-AP4), slightly decreased the frequency of the pyloric rhythm and suppressed spike discharges in the VD neuron. All effects of mGluR agonists were reversible. The effect of l-QA was blocked by the broad spectrum mGluR antagonist (S)-Methyl-4-carboxyphenylglycine (MCPG). The inhibitory effect of L-CCG-I was prevented by MCPG and by the group II/III mGluR antagonist (RS)-alpha-Methyl-4-phosphonophenylglycine (MPPG), and was partially blocked by the group II mGluR antagonist (RS)-1-amino-5-phosphonoindan-1-carboxylic acid (APICA). The inhibitory effect of l-AP4 was blocked by MPPG and partially blocked by APICA. PMID:16256086

  11. On the Brain of a Crustacean: A Morphological Analysis of CaMKII Expression and Its Relation to Sensory and Motor Pathways

    Science.gov (United States)

    Ammar, Dib; Nazari, Evelise M.

    2013-01-01

    Calcium/calmodulin kinase II (CaMKII) is a Ca2+-activated enzyme that is abundant in vertebrate and invertebrate brains. However, its characterization is poorly addressed in the nervous system of crustaceans, and, to our knowledge, no studies have determined the microanatomical location of CaMKII in a crustacean species. In this study, we found labeling of CaMKII in the eyestalk and brain of the prawn Macrobrachium acanthurus, by means of immunohistochemistry and Western blotting. Antibodies against neuron (ß tubulin III), glutamate receptor (GluA1), and FMRFamide were used in order to further characterize the CaMKII-labeled cells in the brain. In the eyestalk, strong labeling with CaMKII was observed in the photoreceptors. These cells, especially in the rhabdom, were also reactive to anti-ß tubulin III, whereas the pigment cells were labeled with anti-CaMKII. GluA1 co-located with CaMKII in the photoreceptors. Also, CaMKII appeared in the same sites as FMRFamide in the deutocerebrum, including the olfactory lobe, and in the tritocerebrum, specifically in the antennular neuropil, indicating that the synaptic areas in these regions may be related to sensory-motor processing. In the brain, the identification of cells and regions that express CaMKII contributes to the understanding of the processing of neural connections and the modulating role of CaMKII in decapod crustaceans. PMID:23741406

  12. On exactly conservative integrators

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, J.C. [Max-Planck-Inst. fuer Plasmaphysik, Garching (Germany); Shadwick, B.A. [Univ. of California, Berkeley, CA (United States). Dept. of Physics; Morrison, P.J. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies

    1997-06-01

    Traditional explicit numerical discretizations of conservative systems generically predict artificial secular drifts of nonlinear invariants. These algorithms are based on polynomial functions of the time step. The authors discuss a general approach for developing explicit algorithms that conserve such invariants exactly. They illustrate the method by applying it to the truncated two-dimensional Euler equations.

  13. Biodiversity Conservation in Asia

    OpenAIRE

    Dale Squires

    2014-01-01

    Asian's remarkable economic growth brought many benefits but also fuelled threats to its ecosystems and biodiversity. Economic growth brings biodiversity threats but also conservation opportunities. Continued biodiversity loss is inevitable, but the types, areas and rates of biodiversity loss are not. Prioritising biodiversity conservation, tempered by what is tractable, remains a high priority. Policy and market distortions and failures significantly underprice biodiversity, undermine ecosys...

  14. Creative Soil Conservation

    Science.gov (United States)

    Smith, Martha

    2010-01-01

    Take plant lessons outdoors with this engaging and inquiry-based activity in which third-grade students learn how to apply soil conservation methods to growing plants. They also collect data and draw conclusions about the effectiveness of their method of soil conservation. An added benefit to this activity is that the third-grade students played…

  15. Conservation in transportation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-05-30

    A nationwide examination was made of grassroots energy conservation programs related to transportation. Information compiled from civic groups, trade associations, and corporations is included on driver awareness/mass transit; travel; and ride sharing. It is concluded that a willingness by the public to cooperate in transportation energy conservation exists and should be exploited. (LCL)

  16. Introducing Conservation of Momentum

    Science.gov (United States)

    Brunt, Marjorie; Brunt, Geoff

    2013-01-01

    The teaching of the principle of conservation of linear momentum is considered (ages 15 + ). From the principle, the momenta of two masses in an isolated system are considered. Sketch graphs of the momenta make Newton's laws appear obvious. Examples using different collision conditions are considered. Conservation of momentum is considered…

  17. Broad-Spectrum Solution-Processed Photovoltaics

    Science.gov (United States)

    Ip, Alexander Halley

    High global demand for energy coupled with dwindling fossil fuel supply has driven the development of sustainable energy sources such as solar photovoltaics. Emerging solar technologies aim for low-cost, solution-processable materials which would allow wide deployment. Colloidal quantum dots (CQDs) are such a materials system which exhibits the ability to absorb across the entire solar spectrum, including in the infrared where many technologies cannot harvest photons. However, due to their nanocrystalline nature, CQDs are susceptible to surface-associated electronic traps which greatly inhibit performance. In this thesis, surface engineering of CQDs is presented through a combined ligand approach which improves the passivation of surface trap states. A metal halide treatment is found to passivate quantum dot surfaces in solution, while bifunctional organic ligands produce a dense film in solid state. This approach reduced midgap trap states fivefold compared with conventional passivation strategies and led to solar cells with a record certified 7.0% power conversion efficiency. The effect of this process on the electronic structure is studied through photoelectron spectroscopy. It is found that while the halide provides deep trap passivation, the nature of the metal cation on the CQD surface affects the density of band tail states. This effect is explored further through a wide survey of materials, and it is found that the coordination ability of the metal cation is responsible for the suppression of shallow traps. With this understanding of CQD surface passivation, broad spectral usage is then explored through a study of visible-absorbing organolead halide perovskite materials as well as narrow-bandgap CQD solar cells. Control over growth conditions and modification of electrode interfaces resulted in efficient perovskite devices with effective usages of visible photons. For infrared-absorbing CQDs, it is found that, in addition to providing surface trap

  18. Betaproteobacteria Limnohabitans strains increase fecundity in the crustacean Daphnia magna: symbiotic relationship between major bacterioplankton and zooplankton in freshwater ecosystem.

    Science.gov (United States)

    Peerakietkhajorn, Saranya; Kato, Yasuhiko; Kasalický, Vojtěch; Matsuura, Tomoaki; Watanabe, Hajime

    2016-09-01

    How symbioses between bacteria and aquatic animals influence food webs in freshwater ecosystems is a fundamental question in ecology. We investigated symbiosis between a crustacean zooplankton Daphnia magna and its dominant bacterial symbiont Limnohabitans, an abundant and globally distributed freshwater Betaproteobacteria. Aposymbiotic juvenile Daphnia were prepared and exposed to any of four Limnohabitans sp. - Limnohabitans strains DM1, 2KL-3, 2KL-7 and Limnohabitans planktonicus strain II-D5, all previously found in D. magna digestive tract or culture. Re-infected Daphnia were cultured until they produced the first clutch of juveniles. Limnohabitans strain DM1 and L. planktonicus strain II-D5 successfully re-infected Daphnia through single exposure at the first instar juvenile stage. In contrast to aposymbiotic Daphnia that produced non-viable juveniles, re-infected Daphnia produced viable juveniles and increased fecundity to levels of that of symbiotic Daphnia. Re-infected Daphnia did not increase their number of eggs nor growth rates. Limnohabitans strains 2KL-7 and 2KL-3 could not recover fecundity even in multiple exposures during culture. This study shows the functional evidence demonstrating that a single bacterium Limnohabitans regulates fecundity of the consumer Daphnia through symbiosis. Our results indicated that symbiotic relationship between major bacterioplankton and zooplankton is important for maintaining the population of zooplankton in freshwater ecosystems. PMID:26014379

  19. Crustacean fishery with bottom traps in an area of the southern Tyrrhenian Sea: species composition, abundance and biomass

    Directory of Open Access Journals (Sweden)

    L. CASTRIOTA

    2012-12-01

    Full Text Available The north-eastern coast of Sicily is characterized by deep, steep bottoms, not easily exploitable by trawl fishery. In this area few fishermen use bottom traps to catch shrimps and Norway lobsters. Our studies were aimed at identifying the species’ composition, abundance and biomass of crustaceans exploitable by bottom traps in this area. Monthly samples over one year were obtained from two lines of 30 baited traps each, at depths between 100 and 500 m. One line was placed in an area usually exploited by this fishery; the other line was used in the unexploited deepest bottoms. Trapped specimens were counted and weighed. ANOVA test, post hoc multiple comparisons and Student’s t test were applied on abundance and biomass data, for testing differences between areas, among seasons and species. During 22 fishing days, 23 species characteristic of the bathyal mud assemblage were caught, 8 of which were not considered commercial. Plesionika edwardsii was the most important species, recorded in the whole bathymetric range investigated; Nephrops norvegicus was significantly higher in terms of biomass in the unexploited area. The discard, of slight importance, was mostly represented by the crab Liocarcinus depurator. Spring season yielded the best catches in both areas, showing the highest values for both abundance and biomass

  20. Investigation of signaling molecules and metabolites found in crustacean hemolymph via in vivo microdialysis using a multifaceted mass spectrometric platform.

    Science.gov (United States)

    Jiang, Shan; Liang, Zhidan; Hao, Ling; Li, Lingjun

    2016-04-01

    Neurotransmitters (NTs) are endogenous signaling molecules that play an important role in regulating various physiological processes in animals. Detection of these chemical messengers is often challenging due to their low concentration levels and fast degradation rate in vitro. In order to address these challenges, herein we employed in vivo microdialysis (MD) sampling to study NTs in the crustacean model Cancer borealis. Multifaceted separation tools, such as CE and ion mobility mass spectrometry (MS) were utilized in this work. Small molecules were separated by different mechanisms and detected by MALDI mass spectrometric imaging (MALDI-MSI). Performance of this separation-based MSI platform was also compared to LC-ESI-MS. By utilizing both MALDI and ESI-MS, a total of 208 small molecule NTs and metabolites were identified, of which 39 were identified as signaling molecules secreted in vivo. In addition, the inherent property of sub microscale sample consumption using CE enables shorter time of MD sample collection. Temporal resolution of MD was improved by approximately tenfold compared to LC-ESI-MS, indicating the significant advantage of applying separation-assisted MALDI-MS imaging platform. PMID:26691021

  1. Direct evidence of the cyclooxygenase pathway of prostaglandin synthesis in arthropods: genetic and biochemical characterization of two crustacean cyclooxygenases.

    Science.gov (United States)

    Varvas, Külliki; Kurg, Reet; Hansen, Kristella; Järving, Reet; Järving, Ivar; Valmsen, Karin; Lõhelaid, Helike; Samel, Nigulas

    2009-12-01

    Prostaglandins, well-known lipid mediators in vertebrate animals, have also shown to play certain regulatory roles in insects and other arthropods acting on reproduction, immune system and ion transport. However, knowledge of their biosynthetic pathways in arthropods is lacking. In the present study, we report the cloning and expression of cyclooxygenase (COX) from amphipod crustaceans Gammarus spp and Caprella spp. The amphipod COX proteins contain key residues shown to be important for cyclooxygenase and peroxidase activities. Differently from all other known cyclooxygenases the N-terminal signal sequence of amphipod enzymes is not cleaved during protein expression in mammalian cells. The C-terminus of amphipod COX is shorter than that of mammalian isoforms and lacks the KDEL(STEL)-type endoplasmic reticulum retention/retrieval signal. Despite that, amphipod COX proteins are N-glycosylated and locate similarly to the vertebrate COX on the endoplasmic reticulum and nuclear envelope. Both amphipod COX mRNAs encode functional cyclooxygenases that catalyze the transformation of arachidonic acid into prostaglandins. Using bioinformatic analysis we identified a COX-like gene from the human body louse Pediculus humanus corporis genome that encodes a protein with about 30% sequence identity with human COX-1 and COX-2. Although the COX gene is known to be absent from genomes of Drosophila sp., Aedes aegypti, Bombyx mori, and other insects, our studies establish the existence of the COX gene in certain lineages within the insect world. PMID:19854273

  2. Taxocenosis of mollusks and crustaceans on roots of Rhizophora mangle (Rhizophoraceae at Cispatá Bay, Córdoba, Colombia

    Directory of Open Access Journals (Sweden)

    Jorge Alexander Quirós R

    2013-05-01

    Full Text Available Despite the existing knowledge on the ecology of mangroves at Cispatá Bay, few studies have focused on the association of invertebrates on red mangrove roots, so between December 2010 and September 2011, it was characterized taxocenosis of mollusks and crustaceans on roots of Rhizophora mangle in two study sites at Cispatá Bay, Colombia. For the collections of biological material were randomly taken three red mangrove roots with a diameter. Mollusks and crustaceans were obtained from the root surface with a scraping knife then were removed and fixed in 10 % formalin for later identification to species using specialized taxonomic keys. Of the 12289 individuals collected in the four samples, 10470 belonged to the phylumMollusca (85,2 % and the remaining 1819 to subphylum Crustacea (14,8 %. For mollusks were identified 14 species distributed in 11 families and two classes; Bivalvia and Gastropoda. For crustaceans were identified 24 species distributed in 16 families and four orders; Sessillia, Decapoda, Isopoda and Amphipoda. In both sectors sampling Mytella charruana, Balanus eburneusand Crassostrea rhizophorae were the most important species in terms of abundance, however mollusks like M. charruana and B. eburneus have a great ability to adapt and adjust to changing hydroclimatic, which was reflected in the dominance of these species in the sector with the greatest influence Sinu River. The presence of crustaceans Petrolisthes armatus and Aratus pisonii in the sector with more proximity to the Caribbean Sea indicate that are species with great mobility and physiological adaptation mechanisms.TAXOCENOSIS DE MOLUSCOS Y CRUSTÁCEOS EN RAÍCESDE Rhizophora mangle (RHIZOPHORACEAEEN LA BAHÍA DE CISPATÁ, CÓRDOBA, COLOMBIAA pesar del conocimiento existente sobre la ecología de los manglares en la bahía de Cispatá, pocos estudios han sido enfocados en invertebrados asociados a las raíces del mangle rojo. Entre diciembre 2010 y

  3. Taphonomy and diversity of Middle Miocene decapod crustaceans from the Novohrad-Nógrad Basin, Slovakia, with remarks on palaeobiography

    Science.gov (United States)

    Hyžný, Matúš; Hudáčková, Natália; Szalma, Štefan

    2016-01-01

    Decapod crustacean assemblages from the Middle Miocene (lower ‘Badenian’=Langhian) volcanoclastic Plášťovce Beds (Sebechleby Formation) in the Slovakian part of the Novohrad-Nógrad Basin comprise five species in five families (Callianassidae, Laomediidae, Munididae, Cancridae and Retroplumidae) and are dominated by the cancrid crab Tasadia carniolica (Bittner, 1884). Munida sp. constitutes the first record of this genus from Slovakia and the second from the European Neogene. Burrowing shrimp (Jaxea kuemeli Bachmayer, 1954) are associated with burrows tentatively attributed to this species. The occurrence of Retropluma slovenica Gašparič & Hyžný, 2014, previously recorded from the Lower Miocene of Slovenia, extends both the geographical distribution and stratigraphical range of the species. Differential decapod diversity at four localities in the Plášťovce area can be explained by collecting bias and palaeoenvironmental factors. The palaeosetting is interpreted as a muddy-bottom, nearshore zone with a water depth of approximately 100 m. Abundant articulated crabs suggest rapid burial. Third maxillipeds in open posture in some specimens may indicate respiratory stress of the animals, suggesting episodic events of rapid volcanoclastic flows responsible for killing crabs and promoting their preservation. Species composition of the decapod fauna of the Plášťovce Beds further strengthens similarities with Miocene faunas from the North Sea Basin.

  4. Status of selected bottomfish and crustacean species in Prince William Sound following the Exxon Valdez oil spill

    International Nuclear Information System (INIS)

    Exposure and possible adverse effects of the Exxon Valdez oil spill (EVOS) at depth were studied between 1989 and 1991 on several species of crustaceans, molluscs, and finfish that are characterized by ontogenetic shifts in distribution from meroplanktonic larvae to benthic and demersal juveniles and adults. The authors approach was to search for (1) evidence of exposure to Exxon Valdez crude oil (EVC) at depth (generally between 20 to 150 m) and (2) measurable perturbations at both the individual and population levels. Primary species targeted were Tanner crab (Chionoecetes bairdi), several pandalid shrimps (Pandalus platyceros, P. hypsinotus, P. borealis), flathead sole (Hippoglossoides elassodon), and several bivalves including scallops (Chlamys rubida) and infaunal clams (Nuculana, Yoldia, and Macoma spp.). The survey design provided a comparison between variables measured in oiled bays around Knight Island and non-oiled bays at other locations within Prince William Sound. Polycyclic aromatic hydrocarbons (PAHs) of petrogenic origin were measured in all bays sampled in this study and levels of PAHs derived from EVC were elevated in the oiled bays following the spill, yet attenuated to less than 200 ng/g sediment by 1991. 95 refs., 22 figs., 6 tabs

  5. Paradigms for parasite conservation.

    Science.gov (United States)

    Dougherty, Eric R; Carlson, Colin J; Bueno, Veronica M; Burgio, Kevin R; Cizauskas, Carrie A; Clements, Christopher F; Seidel, Dana P; Harris, Nyeema C

    2016-08-01

    Parasitic species, which depend directly on host species for their survival, represent a major regulatory force in ecosystems and a significant component of Earth's biodiversity. Yet the negative impacts of parasites observed at the host level have motivated a conservation paradigm of eradication, moving us farther from attainment of taxonomically unbiased conservation goals. Despite a growing body of literature highlighting the importance of parasite-inclusive conservation, most parasite species remain understudied, underfunded, and underappreciated. We argue the protection of parasitic biodiversity requires a paradigm shift in the perception and valuation of their role as consumer species, similar to that of apex predators in the mid-20th century. Beyond recognizing parasites as vital trophic regulators, existing tools available to conservation practitioners should explicitly account for the unique threats facing dependent species. We built upon concepts from epidemiology and economics (e.g., host-density threshold and cost-benefit analysis) to devise novel metrics of margin of error and minimum investment for parasite conservation. We define margin of error as the risk of accidental host extinction from misestimating equilibrium population sizes and predicted oscillations, while minimum investment represents the cost associated with conserving the additional hosts required to maintain viable parasite populations. This framework will aid in the identification of readily conserved parasites that present minimal health risks. To establish parasite conservation, we propose an extension of population viability analysis for host-parasite assemblages to assess extinction risk. In the direst cases, ex situ breeding programs for parasites should be evaluated to maximize success without undermining host protection. Though parasitic species pose a considerable conservation challenge, adaptations to conservation tools will help protect parasite biodiversity in the face of

  6. Conservation by design.

    Science.gov (United States)

    Root-Bernstein, Meredith; Ladle, Richard J

    2010-10-01

    Conservation researchers are increasingly aware of the need to conduct interdisciplinary research and to engage nonscientists in practical applications of conservation biology. But so far, industrial designers have been left out of such collaboration and outreach efforts. Conservation of wildlife often depends on products such as nest boxes, feeders, barriers, and corridors, all of which have a designed component that is frequently overlooked. Furthermore, many products are adopted without testing on short or long time scales. We argue that the design of products for conservation, and hence their functionality, effectiveness, and value, can be improved through collaboration with industrial designers. We see four key benefits that can arise from interactions with industrial designers: improvement of product quality and value, innovation and improvement in functionality of products, harmonization of conservation products with local values, and development of a psychological biomimesis approach to design. The role of industrial designers in conservation projects would be to improve factors such as product durability, affordability, functionality, and aesthetic appeal to local people. Designers can also help to create multiple product options whose success can be tested in the field. We propose that collaborations with industrial designers can contribute to the development of improvements to existing products and innovations in the practice of animal conservation. PMID:20408866

  7. A Potent and Broad Neutralizing Antibody Recognizes and Penetrates the HIV Glycan Shield

    Energy Technology Data Exchange (ETDEWEB)

    Pejchal, Robert; Doores, Katie J.; Walker, Laura M.; Khayat, Reza; Huang, Po-Ssu; Wang, Sheng-Kai; Stanfield, Robyn L.; Julien, Jean-Philippe; Ramos, Alejandra; Crispin, Max; Depetris, Rafael; Katpally, Umesh; Marozsan, Andre; Cupo, Albert; Maloveste, Sebastien; Liu, Yan; McBride, Ryan; Ito, Yukishige; Sanders, Rogier W.; Ogohara, Cassandra; Paulson, James C.; Feizi, Ten; Scanlan, Christopher N.; Wong, Chi-Huey; Moore, John P.; Olson, William C.; Ward, Andrew B.; Poignard, Pascal; Schief, William R.; Burton, Dennis R.; Wilson, Ian A. (UWASH); (Progenics); (ICL); (Weill-Med); (NIH); (JSTA); (Scripps); (Oxford)

    2015-10-15

    The HIV envelope (Env) protein gp120 is protected from antibody recognition by a dense glycan shield. However, several of the recently identified PGT broadly neutralizing antibodies appear to interact directly with the HIV glycan coat. Crystal structures of antigen-binding fragments (Fabs) PGT 127 and 128 with Man{sub 9} at 1.65 and 1.29 angstrom resolution, respectively, and glycan binding data delineate a specific high mannose-binding site. Fab PGT 128 complexed with a fully glycosylated gp120 outer domain at 3.25 angstroms reveals that the antibody penetrates the glycan shield and recognizes two conserved glycans as well as a short {beta}-strand segment of the gp120 V3 loop, accounting for its high binding affinity and broad specificify. Furthermore, our data suggest that the high neutralization potency of PGT 127 and 128 immunoglobulin Gs may be mediated by cross-linking Env trimers on the viral surface.

  8. Building for energy conservation

    Energy Technology Data Exchange (ETDEWEB)

    O' Callaghan, P.W.

    1978-01-01

    The need to conserve energy, how energy may be saved, and thermal energy conservation in buildings are discussed in the introductory chapter. Heat gains and losses, fluid flow, convective heat transfer, and radiative heat transfer are covered in chapter 2, fundamentals. Thermal comfort, climate, heat losses from buildings, heat gains to buildings, thermal network analysis, energy thrift, secondary effects, waste heat recovery, and altenative energy sources are subjects covered in chapters 3 to 11. The final chapter, prospectus for the future, covers discussions on areas where energy should be saved, total energy, energy management, energy accounting, and practicing energy conservation. (MCW)

  9. Transport and conservation laws

    OpenAIRE

    Zotos, X.; F. Naef; Prelovsek, P.

    1996-01-01

    We study the lowest order conservation laws in one-dimensional (1D) integrable quantum many-body models (IQM) as the Heisenberg spin 1/2 chain, the Hubbard and t-J model. We show that the energy current is closely related to the first conservation law in these models and therefore the thermal transport coefficients are anomalous. Using an inequality on the time decay of current correlations we show how the existence of conserved quantities implies a finite charge stiffness (weight of the zero...

  10. Inhibitors of cellular kinases with broad-spectrum antiviral activity for hemorrhagic fever viruses.

    Science.gov (United States)

    Mohr, Emma L; McMullan, Laura K; Lo, Michael K; Spengler, Jessica R; Bergeron, Éric; Albariño, César G; Shrivastava-Ranjan, Punya; Chiang, Cheng-Feng; Nichol, Stuart T; Spiropoulou, Christina F; Flint, Mike

    2015-08-01

    Host cell kinases are important for the replication of a number of hemorrhagic fever viruses. We tested a panel of kinase inhibitors for their ability to block the replication of multiple hemorrhagic fever viruses. OSU-03012 inhibited the replication of Lassa, Ebola, Marburg and Nipah viruses, whereas BIBX 1382 dihydrochloride inhibited Lassa, Ebola and Marburg viruses. BIBX 1382 blocked both Lassa and Ebola virus glycoprotein-dependent cell entry. These compounds may be used as tools to understand conserved virus-host interactions, and implicate host cell kinases that may be targets for broad spectrum therapeutic intervention. PMID:25986249

  11. The constancy of gene conservation across divergent bacterial orders

    Directory of Open Access Journals (Sweden)

    Ackermann Martin

    2009-01-01

    Full Text Available Abstract Background Orthologous genes are frequently presumed to perform similar functions. However, outside of model organisms, this is rarely tested. One means of inferring changes in function is if there are changes in the level of gene conservation and selective constraint. Here we compare levels of gene conservation across three bacterial groups to test for changes in gene functionality. Findings The level of gene conservation for different orthologous genes is highly correlated across clades, even for highly divergent groups of bacteria. These correlations do not arise from broad differences in gene functionality (e.g. informational genes vs. metabolic genes, but instead seem to result from very specific differences in gene function. Furthermore, these functional differences appear to be maintained over very long periods of time. Conclusion These results suggest that even over broad time scales, most bacterial genes are under a nearly constant level of purifying selection, and that bacterial evolution is thus dominated by selective and functional stasis.

  12. Metro Conservation Corridors

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Metro Conservation Corridors (MeCC) grow out of the natural resource analysis work done by the DNR in the late '90's, documented in the Metro Greenprint...

  13. Reasons to Conserve Nature.

    Science.gov (United States)

    Pearson, Richard G

    2016-05-01

    Is it sufficient to base arguments for conservation on the intrinsic value of nature, regardless of the services and economic benefits that biodiversity provides for humans? This question underlies much recent debate that has been at times acrimonious and has led to calls for a more inclusive approach to conservation. Yet melding different ideologies within a unified conceptual framework has proven difficult. Here I describe an approach that recognizes the importance of the level of biological organization and spatial extent in determining the strength of alternative arguments for why we should conserve nature. I argue that the framework helps reconcile contrasting viewpoints and brings clarity to when different conservation management approaches (for instance, regulation versus monetary valuation) are most appropriate. PMID:26936225

  14. Landscape Conservation Cooperatives

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Landscape Conservation Cooperatives (LCCs) are public-private partnerships composed of states, tribes, federal agencies, non-governmental organizations,...

  15. Hearing Conservation Team

    Data.gov (United States)

    Federal Laboratory Consortium — The Hearing Conservation Team focuses on ways to identify the early stages of noise-induced damage to the human ear. Our current research involves the evaluation of...

  16. Fundamentals of conservation in the Southwest

    Energy Technology Data Exchange (ETDEWEB)

    Leopold, A.

    The author discusses mineral and organic wealth in the Southwest as an economic resource. Their value is affected more or less by that idea or method of development broadly called conservation. With the exception of coal, the mineral wealth of the southwest, from the standpoint of an economic foundation for society, is exhaustible. The coal available in the area will probably always be handicapped by long hauls and the absence of water. The organic resources, mainly farms, ranges, forests, waters, and water powers, are in a rundown condition. The author concludes that the deterioration of the fundamental resources - land and water - is in the nature of permanent destruction; the process is also seen to be cumulative and gaining in momentum every year. To explore the deterioration, the author discusses the climate and the delicate balance of the fragile ecosystem of the southwest. He concludes the analysis with a discussion of the moral issues involved, specifically the morality of conservation. (SAC)

  17. Energy conservation indicators. 1982 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Belzer, D.B.

    1982-09-01

    A series of Energy Conservation Indicators were developed for the Department of Energy to assist in the evaluation of current and proposed conservation strategies. As descriptive statistics that signify current conditions and trends related to efficiency of energy use, indicators provide a way of measuring, monitoring, or inferring actual responses by consumers in markets for energy services. Related sets of indicators are presented in some 40 one-page indicator summaries. Indicators are shown graphically, followed by several paragraphs that explain their derivation and highlight key findings. Indicators are classified according to broad end-use sectors: Aggregate (economy), Residential, Commercial, Industrial, Transportation and Electric Utilities. In most cases annual time series information is presented covering the period 1960 through 1981.

  18. Conservation Kickstart- Catalyzing Conservation Initiatives Worldwide

    Science.gov (United States)

    Treinish, G.

    2014-12-01

    Adventurers and Scientists for Conservation (ASC) is a nonprofit organization that collects environmental data to catalyze conservation initiatives worldwide. Adventure athletes have the skills and motivation to reach the most remote corners of the world. ASC utilizes those skills to provide the scientific community with data while providing the outdoor community with purpose beyond the personal high of reaching a summit or rowing across an ocean. We carefully select projects, choosing partnerships that will maximize the impact of ASC volunteers. Each project must have a clear path to a tangible conservation outcome and demonstrate a clear need for our brand of volunteers. We partner with government agencies, universities, and independant reseachers to kickstart data collection efforts around the world. Last year, through a partnership with the Olympic National Forest, 20 volunteers from the Seattle area set up and monitored camera traps in an effort to survey for costal Pacific marten. Our work led to the species' listing as "critically imperiled" with NatureServe. A partnership with the inaugural Great Pacific Race, engaging trans-Pacific rowing teams, searched for microplastics in the Pacific Ocean as part of our ongoing microplastics campaign. In a multi-year partnership with the American Prairie Reserve (APR), ASC volunteer crews live and work on the Reserve collecting wildlife data year round. The data we obtain directly informs the Reserve's wildlife management decisions. On this project, our crews have safely and effectively navigated temperature extremes from -30 degrees to 100+ degrees while traveling in a remote location. We are currently scouting projects in the Okavango Delta of Botswana and the rainforest of Suriname where we will be able to cover large amounts of area in a short periord of time. ASC is at the crossroads of the adventure and coservation science communities. Our approach of answering specific questions by using highly skilled and

  19. Overview of energy-conservation research opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Hopp, W.J.; Hauser, S.G.; Hane, G.J.; Gurwell, W.E.; Bird, S.P.; Cliff, W.C.; Williford, R.E.; Williams, T.A.; Ashton, W.B.

    1981-12-01

    This document is a study of research opportunities that are important to developing advanced technologies for efficient energy use. The study's purpose is to describe a wide array of attractive technical areas from which specific research and development programs could be implemented. Research areas are presented for potential application in each of the major end-use sectors. The study develops and applies a systematic approach to identifying and screening applied energy conservation research opportunities. To broadly cover the energy end-use sectors, this study develops useful information relating to the areas where federally-funded applied research will most likely play an important role in promoting energy conservation. This study is not designed to produce a detailed agenda of specific recommended research activities. The general information presented allows uniform comparisons of disparate research areas and as such provides the basis for formulating a cost-effective, comprehensive federal-applied energy conservation research strategy. Chapter 2 discusses the various methodologies that have been used in the past to identify research opportunities and details the approach used here. In Chapters 3, 4, and 5 the methodology is applied to the buildings, transportation, and industrial end-use sectors and the opportunities for applied research in these sectors are discussed.Chapter 6 synthesizes the results of the previous three chapters to give a comprehensive picture of applied energy conservation research opportunities across all end-use sectors and presents the conclusions to the report.

  20. Brain architecture in the terrestrial hermit crab Coenobita clypeatus (Anomura, Coenobitidae, a crustacean with a good aerial sense of smell

    Directory of Open Access Journals (Sweden)

    Hansson Bill S

    2008-06-01

    Full Text Available Abstract Background During the evolutionary radiation of Crustacea, several lineages in this taxon convergently succeeded in meeting the physiological challenges connected to establishing a fully terrestrial life style. These physiological adaptations include the need for sensory organs of terrestrial species to function in air rather than in water. Previous behavioral and neuroethological studies have provided solid evidence that the land hermit crabs (Coenobitidae, Anomura are a group of crustaceans that have evolved a good sense of aerial olfaction during the conquest of land. We wanted to study the central olfactory processing areas in the brains of these organisms and to that end analyzed the brain of Coenobita clypeatus (Herbst, 1791; Anomura, Coenobitidae, a fully terrestrial tropical hermit crab, by immunohistochemistry against synaptic proteins, serotonin, FMRFamide-related peptides, and glutamine synthetase. Results The primary olfactory centers in this species dominate the brain and are composed of many elongate olfactory glomeruli. The secondary olfactory centers that receive an input from olfactory projection neurons are almost equally large as the olfactory lobes and are organized into parallel neuropil lamellae. The architecture of the optic neuropils and those areas associated with antenna two suggest that C. clypeatus has visual and mechanosensory skills that are comparable to those of marine Crustacea. Conclusion In parallel to previous behavioral findings of a good sense of aerial olfaction in C. clypeatus, our results indicate that in fact their central olfactory pathway is most prominent, indicating that olfaction is a major sensory modality that these brains process. Interestingly, the secondary olfactory neuropils of insects, the mushroom bodies, also display a layered structure (vertical and medial lobes, superficially similar to the lamellae in the secondary olfactory centers of C. clypeatus. More detailed analyses with

  1. Fatty acids in six small pelagic fish species and their crustacean prey from the mindanao sea, southern Philippines.

    Science.gov (United States)

    Metillo, Ephrime Bicoy; Aspiras-Eya, Anna Arlene

    2014-08-01

    Fatty acids are important in human health and useful in the analysis of the marine food web, however information on tropical pelagic organisms is scarce. Six zooplanktivorous small pelagic fish species (Decapterus kurroides, Decapterus macarellus, Selar crumenophthalmus, Sardinella lemuru, Spratilloides gracilis and Stolephorus insularis) and four of their zooplanktonic crustacean prey [three sergestoid species (Acetes erythraeus, Acetes intermedius and Lucifer penicillifer) and one calanoid copepod (Acartia erythraea)] were collected from the Mindanao Sea, and their fatty acids were profiled. The resulting profiles revealed 17 fatty acids that were specific to certain species and 9 {myristic acid [C14:0], palmitic acid [C16:0], stearic acid [C18:0]; palmitoleic acid [C16:1], oleic acid [C18:1n9c], linoleic acid [C18:2n6c], linolenic acid [C18:3n3], eicosapentaenoic acid (EPA) [C20:5n3] and docosahexaenoic acid (DHA) [C22:6n3]} that were common to all species. Cluster analysis and non-metric multidimensional scaling (NMDS) of fatty acids indicate a high similarity in profiles in all species, but separate fish and zooplankton clusters were obtained. Mackerel species (D. macarellus, D. kurroides and S. crumenophthalmus) had concentrations of total n-3 fatty acids that match those of their Acetes prey. The copepod A. erythraea and the sergestoid L. penicillifer exhibited the lowest values of the EPA:DHA ratio, which was most likely due to their phytoplanktivorous feeding habits, but the occurrence of the highest values of the ratio in Acetes suggests the inclusion of plant detritus in their diet. DHA values appear to affirm the trophic link among copepod, Lucifer, Acetes and mackerel species. PMID:25210591

  2. Using strategic foresight to assess conservation opportunity.

    Science.gov (United States)

    Cook, Carly N; Wintle, Bonnie C; Aldrich, Stephen C; Wintle, Brendan A

    2014-12-01

    The nature of conservation challenges can foster a reactive, rather than proactive approach to decision making. Failure to anticipate problems before they escalate results in the need for more costly and time-consuming solutions. Proactive conservation requires forward-looking approaches to decision making that consider possible futures without being overly constrained by the past. Strategic foresight provides a structured process for considering the most desirable future and for mapping the most efficient and effective approaches to promoting that future with tools that facilitate creative thinking. The process involves 6 steps: setting the scope, collecting inputs, analyzing signals, interpreting the information, determining how to act, and implementing the outcomes. Strategic foresight is ideal for seeking, recognizing, and realizing conservation opportunities because it explicitly encourages a broad-minded, forward-looking perspective on an issue. Despite its potential value, the foresight process is rarely used to address conservation issues, and previous attempts have generally failed to influence policy. We present the strategic foresight process as it can be used for proactive conservation planning, describing some of the key tools in the foresight tool kit and how they can be used to identify and exploit different types of conservation opportunities. Scanning is an important tool for collecting and organizing diverse streams of information and can be used to recognize new opportunities and those that could be created. Scenario planning explores how current trends, drivers of change, and key uncertainties might influence the future and can be used to identify barriers to opportunities. Backcasting is used to map out a path to a goal and can determine how to remove barriers to opportunities. We highlight how the foresight process was used to identify conservation opportunities during the development of a strategic plan to address climate change in New York

  3. Hydrology and Conservation Ecology

    Science.gov (United States)

    Narayanan, M.

    2006-12-01

    Responses to change in the behavior of ecological systems are largely governed by interactions at different levels. Research is essential and is to be necessarily designed to gain insights into various interactions at the community level. Sustainable resource management is only possible if conservation of biodiversity can be accomplished by properly using the knowledge discovered. It is well known that the United States Department of Agriculture provides technical information, resources, and data necessary to assist the researchers in addressing their conservation needs. Conservation aims to protect, preserve and conserve the earth's natural resources. These include, but not limited to the conservation of soil, water, minerals, air, plants and all living beings. The United States Department of Agriculture also encourages farmers and ranchers to voluntarily address threats to soil and water. Protection of wetlands and wildlife habitat has been on the radar screen of conservation experts for a very long time. The main objective has always been to help farmers and landowners conform and comply with federal and state environmental laws. During the implementation phase, farmers should be encouraged to make beneficial, cost-effective changes to methods of irrigation systems. In some cases, the hydrologic regime of the project area can be thought of as principally an issue of river flow regimes for floodplain forests. In this presentation, the author tries to focus on the impact of hydrology and conservation ecology on global warming. He also discusses the impact of hydrology and conservation ecology global air concerns such as greenhouse gas concentrations in the atmosphere. References: Chow, V. T, D. R. Maidment, and L. W. Mays. 1988. Applied Hydrology. McGraw-Hill, Inc. U.S. Soil Conservation Service. Technical Release 55: Urban Hydrology for Small Watersheds. USDA (U.S. Department of Agriculture). June 1986. Lehner, B. and P. Döll (2004). Development and validation

  4. Ensamble de crustáceos bentónicos en un lago salino tropical Benthic crustaceans assemblage in a tropical, saline lake

    Directory of Open Access Journals (Sweden)

    Ma. del Carmen Hernández

    2010-10-01

    Full Text Available El presente trabajo reconoce la composición, estructura y distribución espacial del ensamble de crustáceos bentónicos de Alchichica, un lago salino tropical ubicado en el extremo oriental del altiplano mexicano. El lago presenta una riqueza taxonómica de crustáceos bentónicos compuesta por 1 anfípodo (Hyalella azteca, 1 isópodo (Caecidotea williamsi y 2 ostrácodos (Limnocythere inopinata y Candona sp.. Comparada con otros lagos tropicales, la riqueza de especies es reducida. A pesar de lo anterior, es importante mencionar el grado elevado de endemismo representado por C. williamsi, recientemente descrita para el lago Alchichica; adicionalmente, es factible que tanto Candona como H. azteca sean especies nuevas y endémicas del lago. Los crustáceos bentónicos se distribuyen desde la zona litoral hasta la zona más profunda del lago (62 m con abundancias y riqueza taxonómica variables. Los ostrácodos fueron los crustáceos que con mayor frecuencia se recolectaron en el lago, en la zona litoral, en el talud, y en la zona profunda de la que son habitantes exclusivos. Los anfípodos constituyeron el segundo grupo en abundancia de la zona litoral y talud y estuvieron ausentes en la zona profunda. Los isópodos sólo se encuentran asociados a los depósitos de tufa, hábitat característico del lago que se extiende a lo largo del talud, por lo que con las técnicas de muestreo tradicional empleadas en el presente estudio no fueron capturados. En este ensamble de crustáceos predominan las especies de desarrollo directo y con posiciones tróficas que incluyen componentes herbívoros (H. azteca, omnívoros (C. williamsi y bacterívoros (L. inopinata y Candona sp..This work acknowledges the composition, structure and spatial distribution of the benthic crustaceans assemblage of Alchichica, a tropical saline lake located in the easternmost portion of the Mexican highlands. The benthic crustaceans' assemblage was comprised by 1 amphipod

  5. The Data Conservancy

    Science.gov (United States)

    Choudhury, S.; Duerr, R. E.

    2009-12-01

    NSF's Sustainable Digital Data Preservation and Access Network Partners program is an ambitious attempt to integrate a wide variety of expertise and infrastructure into a network for providing "reliable digital preservation, access, integration, and analysis capabilities for science." One of the first two DataNet award recipients, the Data Conservancy, is itself a network of widely diverse partners led by the libraries at the Johns Hopkins University. The Data Conservancy is built on existing exemplar scientific projects, communities, and virtual organizations that have deep engagement with their user communities, and extensive experience with large-scale distributed system development. Data Conservancy members embrace a shared vision that data curation is not an end, but rather a means to collect, organize, validate, and preserve data needed to address the grand research challenges that face society. Data Conservancy members holdings encompass the entire range of earth, life, and space science data. New to the Data Conservancy is the concept that University libraries will be part of the distributed network of data centers and that data science will become a path in the library and information science curricula. As noted by Winston Tabb (JHU Dean of Libraries) "Data Centers are the new library stacks."

  6. Scientific Opinion on the safety and efficacy of synthetic astaxanthin as feed additive for salmon and trout, other fish, ornamental fish, crustaceans and ornamental birds

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-06-01

    Full Text Available Astaxanthin is a pigmenting carotenoid occurring naturally in plankton, crustaceans and fish. The astaxanthin under assessment is of synthetic origin. The FEEDAP Panel considers synthetic astaxanthin safe for salmonids up to 100 mg/kg complete diet. The conclusion on the safety of astaxanthin for salmonids can be extrapolated to other fish and ornamental fish at the same dose. Dietary concentrations of up to 100 mg astaxanthin/kg feed are safe for crustaceans. The FEEDAP Panel could not conclude on the safety of astaxanthin for ornamental birds. Based on a BMDL10 of 3.4 mg/kg bw per day (calculated for liver hypertrophy in female rat in a carcinogenicity study and applying an uncertainty factor of 100, it is possible to set an ADI of 0.034 mg ATX/kg bw (equivalent to 2.0 mg ATX per 60 kg person per day.  The use of astaxanthin up to the maximum permitted dietary level for salmon and trout is of no concern for the safety of the consumer. As some formulations of astaxanthin may be dusty, and in the absence of data on inhalation toxicity, it is prudent to regard astaxanthin-containing additives as being potentially hazardous by inhalation. In the absence of any information on irritancy to skin or eyes or on skin sensitisation, astaxanthin-containing additives should be regarded as hazardous by exposure to skin or eyes. The FEEDAP Panel considers that the use of synthetic astaxanthin (100 mg astaxanthin/kg fish feed does not pose a significant additional risk to the environment compared with natural astaxanthin. Astaxanthin is efficacious in colouring the flesh of salmonids and the epidermis of crustaceans. Astaxanthin is efficacious in pigmenting the flesh of food-producing fish other than salmonids and the skin of ornamental fish. No conclusion can be made on the efficacy of oral astaxanthin in pigmenting the plumage of ornamental birds.

  7. Broad Niche Overlap between Invasive Nile Tilapia Oreochromis niloticus and Indigenous Congenerics in Southern Africa: Should We be Concerned?

    OpenAIRE

    Tsungai A. Zengeya; Anthony J. Booth; Chimimba, Christian T

    2015-01-01

    This study developed niche models for the native ranges of Oreochromis andersonii, O. mortimeri, and O. mossambicus, and assessed how much of their range is climatically suitable for the establishment of O. niloticus, and then reviewed the conservation implications for indigenous congenerics as a result of overlap with O. niloticus based on documented congeneric interactions. The predicted potential geographical range of O. niloticus reveals a broad climatic suitability over most of southern...

  8. Governance principles for wildlife conservation in the 21st century

    Science.gov (United States)

    Decker, Daniel; Smith, Christian; Forstchen, Ann; Hare, Darragh; Pomeranz, Emily; Doyle-Capitman, Catherine; Schuler, Krysten; Organ, John

    2016-01-01

    Wildlife conservation is losing ground in the U.S. for many reasons. The net effect is declines in species and habitat. To address this trend, the wildlife conservation institution (i.e., all customs, practices, organizations and agencies, policies, and laws with respect to wildlife) must adapt to contemporary social–ecological conditions. Adaptation could be supported by clear guidelines reflecting contemporary expectations for wildlife governance. We combine elements of public trust thinking and good governance to produce a broad set of wildlife governance principles. These principles represent guidance for ecologically and socially responsible wildlife conservation. They address persistent, systemic problems and, if adopted, will bring the institution into line with modern expectations for governance of public natural resources. Implementation will require changes in values, objectives, and processes of the wildlife conservation institution. These changes may be difficult, but promise improved wildlife conservation outcomes and increased support for conservation. We introduce challenges and opportunities associated with the principles, and encourage dialogue about them among scientists, practitioners, and other leaders in U.S. wildlife conservation. The principles alone will not change the course of conservation for the better, but may be necessary for such change to occur.

  9. Optimal conservation outcomes require both restoration and protection.

    Science.gov (United States)

    Possingham, Hugh P; Bode, Michael; Klein, Carissa J

    2015-01-01

    Conservation outcomes are principally achieved through the protection of intact habitat or the restoration of degraded habitat. Restoration is generally considered a lower priority action than protection because protection is thought to provide superior outcomes, at lower costs, without the time delay required for restoration. Yet while it is broadly accepted that protected intact habitat safeguards more biodiversity and generates greater ecosystem services per unit area than restored habitat, conservation lacks a theory that can coherently compare the relative outcomes of the two actions. We use a dynamic landscape model to integrate these two actions into a unified conservation theory of protection and restoration. Using nonlinear benefit functions, we show that both actions are crucial components of a conservation strategy that seeks to optimise either biodiversity conservation or ecosystem services provision. In contrast to conservation orthodoxy, in some circumstances, restoration should be strongly preferred to protection. The relative priority of protection and restoration depends on their costs and also on the different time lags that are inherent to both protection and restoration. We derive a simple and easy-to-interpret heuristic that integrates these factors into a single equation that applies equally to biodiversity conservation and ecosystem service objectives. We use two examples to illustrate the theory: bird conservation in tropical rainforests and coastal defence provided by mangrove forests. PMID:25625277

  10. Sampling of fish and crustaceans at the cooling water intake of an estuarine power plant: a comparison with stow net fishery

    OpenAIRE

    J. Maes; Pas, J.; Taillieu, A.; Damme, P.A. van; Ollevier, F.P.

    2001-01-01

    Fish and crustaceans were sampled in November 1995 in the cooling water intake of the nuclear power plant Doel (Zeeschelde Estuary, Belgium) and by stow nets, to determine possible differences in species abundance, species biomass, and mean species length between the two methods. A total of 39 species were caught, 32 by stow net and 33 at the intake, with 26 species being caught by both methods. The abundance and biomass were several times higher at the intake than in the stow net samples. Al...

  11. The lunar-tide cycle viewed by crustacean and mollusc gatherers in the State of Paraíba, Northeast Brazil and their influence in collection attitudes

    Directory of Open Access Journals (Sweden)

    Alves Rômulo RN

    2006-01-01

    Full Text Available Abstract Traditional human communities have a wide knowledge of their environment. Collection of animals in estuarine and coastal areas are directly influenced by tidal cycles. The aim of this study is to evaluate the understanding of the tides associated with the lunar cycle held by people who gather crustaceans and molluscs in the State of Paraiba. The empirical knowledge of 20 crab gatherers and 30 mollusc gatherers was recorded through open interviews and structured questionnaires. The results showed that the gatherers have an accurate comprehension of tidal phenomenon based on their exploitation of natural resources, which perpetuates through generations.

  12. 239+240Pu and 137Cs concentrations in fish, cephalopods, crustaceans, shellfish, and algae collected around the Japanese coast in the early 1990s

    International Nuclear Information System (INIS)

    Marine organisms, i.e. fish, cephalopods, crustaceans, shellfish, and algae, were collected in the early 1990s along the Sea of Japan coast and the Japanese Pacific coast and analyzed for their 239+240Pu and 137Cs concentrations. The 239+240Pu concentrations in muscle of fish were below 0.4 mBq/kg wet wt. and the lowest among the analyzed marine organisms. Most 137Cs concentrations in muscle of fish ranged from 100 to 300 mBq/kg wet wt. Higher concentrations of 239+240Pu, ranging from 1.6 to 5.7 mBq/kg wet wt., were observed in viscera of cephalopods than in their muscle. The 239+240Pu concentrations in whole soft tissues of bivalves varied approximately one order of magnitude from 0.8 to 6.1 mBq/kg wet wt., while 137Cs concentrations had little variation, being approximately 60 mBq/kg wet wt. The 239+240Pu concentrations in algae had a wide variation, ranging from 1.7 to 42.3 mBq/kg wet wt., and were higher than those of the other marine organisms. No statistically significant difference in mean concentrations of 239+240Pu was detected among the whole soft tissues of bivalves, viscera of cephalopods and crustaceans, and whole bodies of cephalopods and crustaceans within the 95% confidence limit. The mean concentrations of 137Cs became higher in the order, cephalopods and crustaceans and bivalves, algae, viscera of fish, muscles of fish. The mean concentrations of 239+240Pu were comparable for algae collected along the Japan Sea coast and the Pacific coast. Furthermore, the difference in mean concentrations of 137Cs in algae between the Japan Sea coast and the Pacific coast was not statistically significant within the 95% confidence limit. These results can be considered to indicate no definite influence from radioactive dumping into the Japan Sea by the former USSR and Russia with respect to radioactive pollution of marine organisms collected along the Japanese coast

  13. Conservation reaches new heights.

    Science.gov (United States)

    Pepall, J; Khanal, P

    1992-10-01

    The conservation program with the management assistance of the Woodlands Mountain Institute in 2 contiguous parks, the Mount Everest National Park in Nepal and the Qomolangma Nature Reserve in China, in 2 countries is described. The focus is on conservation of the complex ecosystem with sustainable development by showing local people how to benefit from the park without environmental damage. Cultural diversity is as important as biological diversity. The area has been designated by UNESCO as a World Heritage Site with the "last pure ecological seed" of the Himalayas. The regional geography and culture are presented. Population growth has impacted natural resources through overgrazing, cultivation of marginal land, and deforestation; future plans to build a dam and road bordering the nature reserve pose other threats. Proposed management plans for the Makalu-Barun Nature Park (established in November 1991) and Conservation Area include a division of the park into nature reserve areas free of human activity, protected areas which permit traditional land use, and special sites and trail for tourists and religious pilgrims. The conservation area will act as a buffer for the park and provide economic opportunities; further subdivisions include land use for biodiversity protection, community forest and pasture, agroforestry, and agriculture and settlement. Efforts will be made to increase the welfare of women and local people; proposed projects include the introduction of higher milk-producing animals for stall feeding. Also proposed is a cultural and natural history museum. 70% of the project's resources will be directed to local community participation in consultation and park maintenance. The project is a model of how conservation and protection of natural resources can coexist with local economic development and participation; an integration of preservation of biological diversity, mountain wisdom, and the value of local people as resources for conservation. PMID

  14. Information, conservation and retrieval

    Energy Technology Data Exchange (ETDEWEB)

    Eng, T. [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Norberg, E. [National Swedish Archives, Stockholm (Sweden); Torbacke, J. [Stockholm Univ. (Sweden). Dept. of History; Jensen, M. [Swedish Radiation Protection Inst., Stockholm (Sweden)

    1996-12-01

    The seminar took place on the Swedish ship for transportation of radioactive wastes, M/S Sigyn, which at summer time is used for exhibitions. The seminar treated items related to general information needs in society and questions related to radioactive waste, i.e. how knowledge about a waste repository should be passed on to future generations. Three contributions are contained in the report from the seminar and are indexed separately: `Active preservation - otherwise no achieves`; `The conservation and dissemination of information - A democratic issue`; and, `Conservation and retrieval of information - Elements of a strategy to inform future societies about nuclear waste repositories`.

  15. Information, conservation and retrieval

    International Nuclear Information System (INIS)

    The seminar took place on the Swedish ship for transportation of radioactive wastes, M/S Sigyn, which at summer time is used for exhibitions. The seminar treated items related to general information needs in society and questions related to radioactive waste, i.e. how knowledge about a waste repository should be passed on to future generations. Three contributions are contained in the report from the seminar and are indexed separately: 'Active preservation - otherwise no achieves'; 'The conservation and dissemination of information - A democratic issue'; and, 'Conservation and retrieval of information - Elements of a strategy to inform future societies about nuclear waste repositories'

  16. Elicitation of broadly neutralizing influenza antibodies in animals with previous influenza exposure.

    Science.gov (United States)

    Wei, Chih-Jen; Yassine, Hadi M; McTamney, Patrick M; Gall, Jason G D; Whittle, James R R; Boyington, Jeffrey C; Nabel, Gary J

    2012-08-15

    The immune system responds to influenza infection by producing neutralizing antibodies to the viral surface protein, hemagglutinin (HA), which regularly changes its antigenic structure. Antibodies that target the highly conserved stem region of HA neutralize diverse influenza viruses and can be elicited through vaccination in animals and humans. Efforts to develop universal influenza vaccines have focused on strategies to elicit such antibodies; however, the concern has been raised that previous influenza immunity may abrogate the induction of such broadly protective antibodies. We show here that prime-boost immunization can induce broadly neutralizing antibody responses in influenza-immune mice and ferrets that were previously infected or vaccinated. HA stem-directed antibodies were elicited in mice primed with a DNA vaccine and boosted with inactivated vaccine from H1N1 A/New Caledonia/20/1999 (1999 NC) HA regardless of preexposure. Similarly, gene-based vaccination with replication-defective adenovirus 28 (rAd28) and 5 (rAd5) vectors encoding 1999 NC HA elicited stem-directed neutralizing antibodies and conferred protection against unmatched 1934 and 2007 H1N1 virus challenge in influenza-immune ferrets. Indeed, previous exposure to certain strains could enhance immunogenicity: The strongest HA stem-directed immune response was observed in ferrets previously infected with a divergent 1934 H1N1 virus. These findings suggest that broadly neutralizing antibodies against the conserved stem region of HA can be elicited through vaccination despite previous influenza exposure, which supports the feasibility of developing stem-directed universal influenza vaccines for humans. PMID:22896678

  17. Targeting an Essential GTPase Obg for the Development of Broad-Spectrum Antibiotics.

    Science.gov (United States)

    Bonventre, Josephine A; Zielke, Ryszard A; Korotkov, Konstantin V; Sikora, Aleksandra E

    2016-01-01

    A promising new drug target for the development of novel broad-spectrum antibiotics is the highly conserved small GTPase Obg (YhbZ, CgtA), a protein essential for the survival of all bacteria including Neisseria gonorrhoeae (GC). GC is the agent of gonorrhea, a prevalent sexually transmitted disease resulting in serious consequences on reproductive and neonatal health. A preventive anti-gonorrhea vaccine does not exist, and options for effective antibiotic treatments are increasingly limited. To address the dire need for alternative antimicrobial strategies, we have designed and optimized a 384-well GTPase assay to identify inhibitors of Obg using as a model Obg protein from GC, ObgGC. The assay was validated with a pilot screen of 40,000 compounds and achieved an average Z' value of 0.58 ± 0.02, which suggests a robust assay amenable to high-throughput screening. We developed secondary assessments for identified lead compounds that utilize the interaction between ObgGC and fluorescent guanine nucleotide analogs, mant-GTP and mant-GDP, and an ObgGC variant with multiple alterations in the G-domains that prevent nucleotide binding. To evaluate the broad-spectrum potential of ObgGC inhibitors, Obg proteins of Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus were assessed using the colorimetric and fluorescence-based activity assays. These approaches can be useful in identifying broad-spectrum Obg inhibitors and advancing the therapeutic battle against multidrug resistant bacteria. PMID:26848972

  18. Two Escape Mechanisms of Influenza A Virus to a Broadly Neutralizing Stalk-Binding Antibody

    Science.gov (United States)

    Chai, Ning; Swem, Lee R.; Reichelt, Mike; Chen-Harris, Haiyin; Luis, Elizabeth; Park, Summer; Fouts, Ashley; Lupardus, Patrick; Wu, Thomas D.; Li, Olga; McBride, Jacqueline; Lawrence, Michael; Xu, Min; Tan, Man-Wah

    2016-01-01

    Broadly neutralizing antibodies targeting the stalk region of influenza A virus (IAV) hemagglutinin (HA) are effective in blocking virus infection both in vitro and in vivo. The highly conserved epitopes recognized by these antibodies are critical for the membrane fusion function of HA and therefore less likely to be permissive for virus mutational escape. Here we report three resistant viruses of the A/Perth/16/2009 strain that were selected in the presence of a broadly neutralizing stalk-binding antibody. The three resistant viruses harbor three different mutations in the HA stalk: (1) Gln387Lys; (2) Asp391Tyr; (3) Asp391Gly. The Gln387Lys mutation completely abolishes binding of the antibody to the HA stalk epitope. The other two mutations, Asp391Tyr and Asp391Gly, do not affect antibody binding at neutral pH and only slightly reduce binding at low pH. Interestingly, they enhance the fusion ability of the HA, representing a novel mechanism that allows productive membrane fusion even in the presence of antibody and hence virus escape from antibody neutralization. Therefore, these mutations illustrate two different resistance mechanisms used by IAV to escape broadly neutralizing stalk-binding antibodies. Compared to the wild type virus, the resistant viruses release fewer progeny viral particles during replication and are more sensitive to Tamiflu, suggesting reduced viral fitness. PMID:27351973

  19. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    Energy Technology Data Exchange (ETDEWEB)

    Kubota-Koketsu, Ritsuko; Mizuta, Hiroyuki [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Oshita, Masatoshi; Ideno, Shoji [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Yunoki, Mikihiro [Osaka Research Laboratory, Benesis Corporation, Yodogawa-ku, Osaka 532-6505 (Japan); Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan); Kuhara, Motoki [Ina Laboratory, Medical and Biological Laboratories Corporation, Ltd., Ina, Nagano 396-0002 (Japan); Yamamoto, Naomasa [Department of Biochemistry, School of Pharmaceutical Sciences, Ohu University, Koriyama, Fukushima 963-8611 (Japan); Okuno, Yoshinobu [Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Kanonji, Kagawa 768-0061 (Japan); Ikuta, Kazuyoshi, E-mail: ikuta@biken.osaka-u.ac.jp [Department of Virology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871 (Japan)

    2009-09-11

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  20. Broad neutralizing human monoclonal antibodies against influenza virus from vaccinated healthy donors

    International Nuclear Information System (INIS)

    Human monoclonal antibodies (HuMAbs) prepared from patients with viral infections could provide information on human epitopes important for the development of vaccines as well as potential therapeutic applications. Through the fusion of peripheral blood mononuclear cells from a total of five influenza-vaccinated volunteers, with newly developed murine-human chimera fusion partner cells, named SPYMEG, we obtained 10 hybridoma clones stably producing anti-influenza virus antibodies: one for influenza A H1N1, four for influenza A H3N2 and five for influenza B. Surprisingly, most of the HuMAbs showed broad reactivity within subtype and four (two for H3N2 and two for B) showed broad neutralizing ability. Importantly, epitope mapping revealed that the two broad neutralizing antibodies to H3N2 derived from different donors recognized the same epitope located underneath the receptor-binding site of the hemagglutinin globular region that is highly conserved among H3N2 strains.

  1. "Conservative" views of abortion.

    Science.gov (United States)

    Devine, P E

    1997-01-01

    The introduction to this essay, which presents and defends the "conservative" position on abortion, explains that this position holds that 1) abortion is wrong because it destroys the fetus; 2) the fetus has full personhood from conception (or very near conception); 3) abortion is only justified under special circumstances, such as when the pregnancy poses a threat to the woman's life; and 4) these conclusions should be reflected in law and public policy. Part 2 sets forth the moral foundations for this position. The third part considers the status of the fetus and reviews the various arguments that have been forwarded to resolve the question, such as the species principle, the potentiality principle, the sentience principle, and the conventionalist principle. Part 4 applies the conservative position to problems posed by hard cases, determines that abortion is a form of homicide from two weeks after fertilization (at the latest), reviews circumstances in which various legal definitions of homicide are applicable, argues for the denial of abortion funding by the state, and notes that violent militancy is not the appropriate response to a belief that abortion should be illegal. Section 5 refutes objections to the conservative position based on the fact that some opponents of abortion also oppose contraception, based on feminist ideals, and based on calls for religious freedom in a pluralistic society. In conclusion, the labels applied to the abortion debate are examined, and it is suggested that "communitarian" is the best term for the conservative position. PMID:12348327

  2. Deficiencies in Water Conservancy

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Recent droughts and floods show the fragility of China’s water conservancy capabilities Be it extreme flooding or severe droughts,China has yet to find a stable middle ground concerning its water supply.These disasters,primarily in the Yangtze

  3. Foundry energy conservation workbook

    Energy Technology Data Exchange (ETDEWEB)

    None

    1990-10-01

    This report discusses methods for promoting energy conservation in foundries. Use of electric power, natural gas, and coke are evaluated. Waste heat recovery systems are considered. Energy consumption in the specific processes of electric melting, natural gas melting, heat treatments, ladle melting, and coke fuel melting is described. An example energy analysis is included. (GHH)

  4. Foundry energy conservation workbook

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-31

    This report discusses methods for promoting energy conservation in foundries. Use of electric power, natural gas, and coke are evaluated. Waste heat recovery systems are considered. Energy consumption in the specific processes of electric melting, natural gas melting, heat treatments, ladle melting, and coke fuel melting is described. An example energy analysis is included. (GHH)

  5. Conservation and gene banking

    Science.gov (United States)

    Plant conservation has several objectives the main ones include safeguarding our food supply, preserving crop wild relatives for breeding and selection of new cultivars, providing material for industrial and pharmaceutical uses and preserving the beauty and diversity of our flora for generations to ...

  6. Energy Conservation Simplified

    Science.gov (United States)

    Hecht, Eugene

    2008-01-01

    The standard formulation of energy conservation involves the subsidiary ideas of kinetic energy ("KE"), work ("W"), thermal energy, internal energy, and a half-dozen different kinds of potential energy ("PE"): elastic, chemical, nuclear, gravitational, and so forth. These quantities came to be recognized during the centuries over which the…

  7. Communities, Cameras, and Conservation

    Science.gov (United States)

    Patterson, Barbara

    2012-01-01

    Communities, Cameras, and Conservation (CCC) is the most exciting and valuable program the author has seen in her 30 years of teaching field science courses. In this citizen science project, students and community volunteers collect data on mountain lions ("Puma concolor") at four natural areas and public parks along the Front Range of Colorado.…

  8. Politics of Conservation

    OpenAIRE

    Ansari, Mohammad Amin

    2009-01-01

    The thesis explores the relationship between politics of state and environmental governance in North-Eastern India.Foucault's idea of art of governmentality has been appled to understand the environmental conservation practices in India. environmental governance in North-Eastern India

  9. Oncoplastic breast conserving surgery

    OpenAIRE

    Mansfield, Lucy; Agrawal, Avi; Cutress, Ramsey I.

    2013-01-01

    Oncoplastic breast conserving surgery is a fundamental component of the repertoire for the management of breast cancer. It facilitates removal of large volumes of breast tissue, and can improve cosmetic outcomes and patient satisfaction whilst maintaining good oncological principles, reducing re-excision and mastectomy rates and assisting in adjuvant radiotherapy planning.

  10. Introduction to conservative mastectomies

    OpenAIRE

    Rancati, Alberto; Gercovich, F. Gustavo

    2015-01-01

    Conservative mastectomy (CM) has become an established alternative in the treatment of breast cancer, offering by different techniques a good cosmetic outcome, as well as oncologic control. The different options to achieve these goals are presented. Oncoplastic treatment of breast cancer needs planning and knowledge of well-established plastic surgery techniques.

  11. Ultra-broad bandwidth parametric amplification at degeneracy.

    Science.gov (United States)

    Limpert, J; Aguergaray, C; Montant, S; Manek-Hönninger, I; Petit, S; Descamps, D; Cormier, E; Salin, F

    2005-09-19

    We report on a novel approach of ultra-broad bandwidth parametric amplification around degeneracy. A bandwidth of up to 400 nm centered around 800 nm is amplified in a BBO crystal by using chirped pump pulses with a bandwitdth as broad as 10 nm. A supercontinuum signal is generated in a microstructured fiber, having to first order a quadratic chirp, which is necessary to ensure temporal overlap of the interacting waves over this broad bandwidth. Furthermore, we discuss the potential of this approach for an octave-spanning parametric amplification. PMID:19498762

  12. [Abundance and richness of mollusks and crustaceans associated to the submerged roots of red mangrove (Rhizophora mangle) at Bocaripo Lagoon, Sucre, Venezuela].

    Science.gov (United States)

    Cedeño, Jennellis; Jiménez Prieto, Mayré; Pereda, Luisana; Allen, Thays

    2010-10-01

    Mangrove roots are important habitats for many species. The abundance and richness of mollusks and crustaceans associated with the roots demerged of Rhizophora mangle was studied. The samples were gathered between February 2005 and January 2006, in Bocaripo lagoon, north coast of Sucre state, Venezuela. Five stations were established inside the lagoon; on every station two roots were chosen at random, put in plastic bags and scraped. The associated organisms were separated by taxa and fixed in 10% formaldehyde. One thousand ninety two specimens of mollusks, distributed in two classes: Bivalve and Gastropod were collected. Bivalve was the most abundant with 943 individuals. The most representative family was Mytilidae with 6 species, being Musculus lateralis the dominant species. The crustaceans were represented by 372 organisms, belonging to the class Malacostraca, where Panopeus herbstii (169 ind.) was the most abundant species. The families Panopeidae, Porcellanidae and Majidae had the highest number of species. Maximum abundance was in February (224 ind.), with a richness of 25 species and the minimums in November (45 ind.) and a richness of 12 species. The stations 1 and 5 presented the major abundance and richness of organisms, which could be related to environmental conditions favorable, as the major availability of microhabitats and nourishing offer; on the contrary the station 4, presented a more inhospitable environment, due to the high values in the salinity and temperature, which contributes with the minor abundance and richness of the present species. PMID:21302531

  13. Using biochemical markers to assess the effects of imposed temperature stress on freshwater decapod crustaceans: Cherax quadricarinatus as a test case.

    Science.gov (United States)

    Bone, J W P; Renshaw, G M C; Furse, J M; Wild, C H

    2015-04-01

    The effects of thermal stress can impact negatively on the abundance and distribution of temperature-sensitive species, particularly freshwater crustaceans. This study investigated the effects of thermal stress on physiological and biochemical parameters at five treatment temperatures resulting in minimal (25 °C), moderate (27, 29 °C) or severe (31, 33 °C) thermal stress in the common tropical freshwater crayfish Cherax quadricarinatus. The aim was to develop a suite of stress-sensitive assays to use on threatened populations of freshwater crustaceans, particularly those restricted to cooler temperatures and only found in high altitude refugia. Significant increases in indicators of oxidative and metabolic stress were observed at 29 °C and were elevated further at 33 °C. After a 50-day acclimation to an imposed temperature stress, significant changes in the level of total glutathione, total lipids, muscular protein, total haemocyte count, lipid peroxidation and protein carbonyls were observed between treatments while superoxide dismutase activity and haemolymph protein concentrations did not change. The data provided proof of concept that measuring key biochemical responses to high temperature can provide a means of contrasting the level of thermal stress experienced between individuals of the same species adapted to different temperatures. The methods developed are expected to be of use in research on wild populations of other freshwater poikilothermic organisms, particularly those susceptible to increased environmental temperatures associated with climate change. PMID:25528146

  14. A study of the uptake and toxicity of some stable and radioactive pollutants in marine organisms: antimony, silver, cobalt and strontium in mollusks, crustaceans and teleosts

    International Nuclear Information System (INIS)

    Qualitative and quantitative results following direct aquatic contamination of mollusks, crustaceans and teleosts by 125Sb, 110Ag, 60Co, 85Sr are reported. The effects of a number of biotic and abiotic parameters on the contamination of the various organisms and the distribution and elimination of the radionuclides in the tissues were investigated. The transfer of sup(110m)Ag, 60Co and 125Sb was studied in several benthic food chains. The transfer factor (F.T.) between a given trophic level and the initial environment (seawater) was determined as well as various physiological parameters (percentages ingested, assimilated, eliminated via the feces or urine and/or the gills. Elimination and tissue uptake were followed in mollusks and crustaceans. The consequences of contamination by stable and radioactive pollutants on plants and animals were considered. Acute (lethal) toxicity of various metals or metalloids on marine organisms were quantified. More sensitive sublethal tests considering physiological functions or behaviour were used. Irradiation doses to experiment animals were calculated, showing the importance of the (internal or external distribution of radionuclides and individual geometries on the total exposure dose

  15. Silencing two main isoforms of crustacean hyperglycemic hormone (CHH induces compensatory expression of two CHH-like transcripts in the red swamp crayfish Procambarus clarkii

    Directory of Open Access Journals (Sweden)

    C Manfrin

    2015-01-01

    Full Text Available RNA interference has frequently been applied to modulate gene function in organisms. With the aim of creating new autocidal methods based on neuro-endocrine disruptors for invasive populations of Procambarus clarkii, we silenced the Crustacean Hyperglycemic Hormone (CHH by injecting the corresponding dsRNA. CHH is a pleiotropic hormone that primarily regulates the mobilization of energy reserves and plays a pivotal role in stress responses. Here, we describe two experiments aimed at testing whether CHH silencing significantly alters important physiological aspects. The first experiment investigates the effects of CHH silencing at the glycemic and transcriptomic level in the eyestalk. The second experiment explores the long-term effects of CHH silencing and the effects on mortality and moulting rates. Osmotic deficits and mortality were recorded in specimens injected with CHH dsRNA, whilst controls were injected with GFP dsRNA. After 20 days, despite still silenced for CHH, individuals that survived recovered a strong hyperglycemic response after serotonin injection due to the compensatory effect of two peptides belonging to the crustacean neurohormone CHH protein family

  16. Broad Spectrum Sanitizing Wipes with Food Additives Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcide proposes to develop novel multipurpose non-toxic sanitizing wipes that are aqueous based, have shelf life of 3-5 years, have broad spectrum microbicidal...

  17. AGN Broad Line Regions Scale with Bolometric Luminosity

    CERN Document Server

    Trippe, Sascha

    2015-01-01

    The masses of supermassive black holes in active galactic nuclei (AGN) can be derived spectroscopically via virial mass estimators based on selected broad optical/ultraviolet emission lines. These estimates commonly use the line width as a proxy for the gas speed and the monochromatic continuum luminosity as a proxy for the radius of the broad line region. However, if the size of the broad line region scales with bolometric rather than monochromatic AGN luminosity, mass estimates based on different emission lines will show a systematic discrepancy which is a function of the color of the AGN continuum. This has actually been observed in mass estimates based on H-alpha / H-beta and C IV lines, indicating that AGN broad line regions indeed scale with bolometric luminosity. Given that this effect seems to have been overlooked as yet, currently used single-epoch mass estimates are likely to be biased.

  18. Packaging and Performance of 980nm Broad Area Semiconductor Lasers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    High power broad area semiconductor lasers have found increasing applications in pumping of solid state laser systems and fiber amplifiers, frequency doubling, medical systems and material processing.Packaging including the assembly design, process and thermal management, has a significant impact on the optical performance and reliability of a high power broad area laser. In this paper, we introduce the package structures and assembling process of 980nm broad area lasers and report the performances including output power, thermal behavior and far fields.We will report two types of high power broad area laser assemblies.One is a microchannel liquid cooled assembly and the other is a conduction cooled CT-mount assembly. Optical powers of 15W and 10W were achieved from a 980nm broad area laser with a 120 μ m stripe width in a microchannel liquid cooled assembly and conduction cooled CT-mount assembly, respectively.Furthermore,a high power of 6.5W out of fiber was demonstrated from a pigtailed, fully packaged butterfly-type module without TEC (Thermoelectric cooler).The measurement results showed that thermal management is the key in not only improving output power, but also significantly improving beam divergence and far field distribution.The results also showed that the die attach solder can significant impact the reliability of high power broad area lasers and that indium solder is not suitable for high power laser applications due to electromigration at high current densities and high temperatures.

  19. Selling Conservation? Scientific Legitimacy and the Commodification of Conservation Tourism

    Directory of Open Access Journals (Sweden)

    Jon Sadler

    2009-06-01

    Full Text Available Conservation tourism is a rapidly growing subsector of ecotourism that engages paying volunteers as active participants in conservation projects. Once the preserve of charities, the sector now hosts a proliferation of private companies seeking to make money by selling international conservation work to tourists as a commodity. The commodification of conservation depends upon balancing the scientific legitimacy of projects against the need to offer desirable tourist experiences. Drawing on interviews with UK tour operators and their counterparts in South Africa who run the conservation projects, we explore the transnational geography of commercial conservation tourism, charting how scientific legitimacy is constructed and negotiated within the industry. Although conservation tourism makes trade-offs between scientific rigor and neoliberal market logic, it is a partial and plural process that resists simple categorization. We conclude by considering the difference that commodification makes to conservation science, and vice versa.

  20. Mining and nature conservation

    International Nuclear Information System (INIS)

    To an increasing degree the permissibility of mining projects is coming under the purview of nature conservation law. This field of law owes its current prominence largely to the amended Federal Nature Conservation Law and the recurrent effects of the communal habitat protection guidelines on mining operations. This has had momentous consequences for all sectors of the mining industry. The same applies to the rehabilitation of areas formerly used for mining, a very visible example of which is the remediation of former Wismut mines. This congress report on the Third Colloquium on Mining and Environmental Protection and the Tenth Aachen Environmental Meeting contains examples of rehabilitation measures that have been successfully implemented in various branches of mining

  1. Promoting household energy conservation

    International Nuclear Information System (INIS)

    It is commonly assumed that households must change their behaviour to reduce the problems caused by increasing levels of fossil energy use. Strategies for behaviour change will be more effective if they target the most important causes of the behaviour in question. Therefore, this paper first discusses the factors influencing household energy use. Three barriers to fossil fuel energy conservation are discussed: insufficient knowledge of effective ways to reduce household energy use, the low priority and high costs of energy savings, and the lack of feasible alternatives. Next, the paper elaborates on the effectiveness and acceptability of strategies aimed to promote household energy savings. Informational strategies aimed at changing individuals' knowledge, perceptions, cognitions, motivations and norms, as well as structural strategies aimed at changing the context in which decisions are made, are discussed. This paper focuses on the psychological literature on household energy conservation, which mostly examined the effects of informational strategies. Finally, this paper lists important topics for future research

  2. Metrology and Energy Conservation

    Institute of Scientific and Technical Information of China (English)

    Xuan Xiang

    2006-01-01

    @@ May 20 is World Metrology Day and the theme of this year is "Metrology and Energy Conservation." Energy is not only a vital issue for China, but also for the world. In order to implement Proposal of the CPC Central Committee on the 11th Five-Year Program for National Economic and Social Development, the government bulletin of 5th Plenary Session of the 16th CPC Central Committee announced that "there shall be marked improvement on resource utilization; the energy consumption for unit GDP shall cut 20%, water consumption of unit industrial added value drop 30%... and the recycle ratio of industrial solid wastes shall raise by 60%." These are key targets of economic development during the 11th five-year program. To make full use of metrology for energy conservation and energy utilization, the competent metrology department of Chinese Goyernment advanced metrology program in light of China's energy status.

  3. Three strategies for conservation

    Science.gov (United States)

    1975-01-01

    The three strategies considered as energy conservation oriented were given: national energy conservation, electrification, and diversification. The first one applies to the near term period (now-1985), the second one to the mid term (1985-2000), and the third one to the far term (2000- ). The rest of this section was focussed on the near term period. The following proposed actions were considered: (1) roll back the price of newly discovered oil, (2) force conversion of many power plants from gas and oil to coal, (3) freeze gasoline production for three years at 1972 levels, (4) mandate automobile mileage requirements, (5) require industry to improve energy efficiency, and (6) require manufacture of household appliances with greater efficiency. Each of these six actions was described and discussed in more detail.

  4. Conservation of Architectural Heritage

    OpenAIRE

    Quintero, mario Santana; Blake, Bill; Eppich, Rand

    2007-01-01

    Currently, a wide range of digital sensors for capturing our architectural heritage are available. They offer the opportunity to acquire large sets of information in a relatively short time. These sensors include digital photography (photogrammetry-scaled rectified photography), total stations, laser scanners, high-resolution panoramic devices, etc. A lot of effort has been put in the application of these tools in the field of conservation, however a significant gap exists between the informa...

  5. How conservation scientists work

    OpenAIRE

    Grace, Marcus; Hare, Tony

    2008-01-01

    Being a conservation scientist is not easy. Some may regard it as a ‘soft’ science, and yet it necessarily draws on many other fields of cutting-edge science, such as genetics, ecology, climatology, and behavioural and reproductive science. But these scientists also find themselves working under a wide range of political, socio-economic, and cultural pressures. They often need to make tough, rapid decisions and therefore tread a difficult path between science and society.

  6. Conservative delta hedging

    OpenAIRE

    Mykland, Per Aslak

    2000-01-01

    It is common to have interval predictions for volatilities and other quantities governing securities prices. The purpose of this paper is to provide an exact method for converting such intervals into arbitrage based prices of financial derivatives or industrial or contractual options.We call this procedure conservative delta hedging. The proposed approach will permit an institution’s management a greater oversight of its exposure to risk.

  7. Redshift and Energy Conservation

    OpenAIRE

    Macleod, Alasdair

    2004-01-01

    It has always been considered a serious error to treat the cosmological redshift as a Doppler velocity effect rather than the result of space expansion. It is demonstrated here that in practical terms this is not the case, and that the apparent distance - redshift relation derived from a Doppler interpretation is reasonably consistent with supernova data (though not as good as the standard model with dark energy). The normal Doppler effect is examined in detail and shown to conserve energy as...

  8. Swedish national and local government programs for conservation of energy in buildings

    Science.gov (United States)

    Klingberg, T.; Broechner, J.; Engebeck, L.; Ericsson, C.; Hirn, O.

    A broad scope of subjects within the area of promotion of energy conservation is treated. The Swedish institutional system for building, housing and energy is briefly described. The national energy conservation goal is presented and discussed. Different government measures to promote energy conservation, such as the building codes and the loans and grants system, are described and some questions are raised. Some essays deal with informational programs and training of energy advisors. The conflict between energy aspects and architectural qualities is discussed. Finally, a case-study of energy conservation in three Swedish municipalities is summarized and the activities - and non-activities - of the local authorities are analyzed.

  9. Making conservation research more relevant for conservation practitioners

    NARCIS (Netherlands)

    Laurance, W.F.; Koster, H.; Grooten, M.; Anderson, A.B.; Zuidema, P.A.; Zwick, S.; Zagt, R.J.; Lynam, A.J.; Linkie, M.; Anten, N.P.R.

    2012-01-01

    Conservation scientists and practitioners share many of the same goals. Yet in a majority of cases, we argue, research conducted by academic conservation scientists actually makes surprisingly few direct contributions to environmental conservation. We illustrate how researchers can increase the util

  10. Urban conservation agriculture with vegetables

    OpenAIRE

    D.I.A. Edralin; Kieu, L.N.; TRAN, D; Creason, S.; Manuel R. Reyes

    2014-01-01

    This poster describes the implementation of a project to promote vegetable gardening with conservation agriculture in urban schools. LTRA-12 (Conservation agriculture for food security in Cambodia and the Philippines)

  11. 76 FR 22785 - Wetland Conservation

    Science.gov (United States)

    2011-04-25

    ... 7 CFR Part 12 RIN 0578-AA58 Wetland Conservation AGENCY: Office of the Secretary, United States... concerning the Natural Resources Conservation Service's (NRCS) coordination responsibilities. DATES..., Director, Ecological Sciences Division, U.S. Department of Agriculture, Natural Resources...

  12. Conservation genetics of Iberian raptors

    OpenAIRE

    Martinez–Cruz, B.

    2011-01-01

    In this paper I provide an overview of conservation genetics and describe the management actions in the wild that can benefit from conservation genetic studies. I describe the genetic factors of risk for the survival of wild species, the consequences of loss of genetic diversity, inbreeding and outbreeding depression, and the use of genetic tools to delimitate units of conservation. Then I introduce the most common applications of conservation genetics in the management of wild populations. I...

  13. Conservation genetics of Iberian raptors

    OpenAIRE

    Martínez-Cruz, Begoña

    2011-01-01

    [EN] In this paper I provide an overview of conservation genetics and describe the management actions in the wild that can benefit from conservation genetic studies. I describe the genetic factors of risk for the survival of wild species, the consequences of loss of genetic diversity, inbreeding and outbreeding depression, and the use of genetic tools to delimitate units of conservation. Then I introduce the most common applications of conservation genetics in the management of wild populatio...

  14. Bid Optimization in Broad-Match Ad auctions

    CERN Document Server

    Even-dar, Eyal; Mirrokni, Vahab; Muthukrishnan, S; Nadav, Uri

    2009-01-01

    Ad auctions in sponsored search support ``broad match'' that allows an advertiser to target a large number of queries while bidding only on a limited number. While giving more expressiveness to advertisers, this feature makes it challenging to optimize bids to maximize their returns: choosing to bid on a query as a broad match because it provides high profit results in one bidding for related queries which may yield low or even negative profits. We abstract and study the complexity of the {\\em bid optimization problem} which is to determine an advertiser's bids on a subset of keywords (possibly using broad match) so that her profit is maximized. In the query language model when the advertiser is allowed to bid on all queries as broad match, we present an linear programming (LP)-based polynomial-time algorithm that gets the optimal profit. In the model in which an advertiser can only bid on keywords, ie., a subset of keywords as an exact or broad match, we show that this problem is not approximable within any ...

  15. Cell lineage analysis of the mandibular segment of the amphipod Orchestia cavimana reveals that the crustacean paragnaths are sternal outgrowths and not limbs

    Directory of Open Access Journals (Sweden)

    Scholtz Gerhard

    2006-12-01

    Full Text Available Abstract The question of arthropod head segmentation has become one of the central issues in Evolutionary Developmental Biology. The number of theories pertaining to head segments progressively enlarges, old concepts have been revitalized, and nearly every conceivable composition of the arthropod head has at some point received discussion. One contentious issue involves a characteristic mouthpart in crustaceans – the lower lips or the so-called paragnaths. The paragnaths build the posterior border of the mouth region antagonistic to the upper lip – the labrum. We show here the development of the appendage-like structures in the mandibular region of the amphipod crustacean Orchestia cavimana at a high level of cellular resolution. The embryos are examined during development of the mouthparts using in vivo labeling. An invariant cell division pattern of the mandibular segment was detected by 4D-microscopy and a preliminary model for pattern of the first cleavages in the mandibular region created. With this indispensable precondition single ectodermal cells of the grid-like pattern were labeled with DiI – a lipophilic fluorescent dye – to trace cell lineages and determine the clonal composition of the developing mouthparts, especially the mandibular segment. From our data it is evident that the paragnaths are sternal outgrowths of the mandible segment. The assumption of the limb nature of paragnaths and the presence of an additional head segment between the mandibular and the second antennal segments are clearly refuted by our data. Our results show the power of cell lineage and clonal analyses for inferences on the nature, origin and thus homology of morphological structures. With this kind of investigation morphological and gene expression data can be complemented. We discuss notable similarities of paragnath anlagen to those of the hypopharynx complex in myriapods and hexapods. The fact that both structures grow out as two lateral buds

  16. Induction of broadly neutralizing H1N1 influenza antibodies by vaccination.

    Science.gov (United States)

    Wei, Chih-Jen; Boyington, Jeffrey C; McTamney, Patrick M; Kong, Wing-Pui; Pearce, Melissa B; Xu, Ling; Andersen, Hanne; Rao, Srinivas; Tumpey, Terrence M; Yang, Zhi-Yong; Nabel, Gary J

    2010-08-27

    The rapid dissemination of the 2009 pandemic influenza virus underscores the need for universal influenza vaccines that elicit protective immunity to diverse viral strains. Here, we show that vaccination with plasmid DNA encoding H1N1 influenza hemagglutinin (HA) and boosting with seasonal vaccine or replication-defective adenovirus 5 vector encoding HA stimulated the production of broadly neutralizing influenza antibodies. This prime/boost combination increased the neutralization of diverse H1N1 strains dating from 1934 to 2007 as compared to either component alone and conferred protection against divergent H1N1 viruses in mice and ferrets. These antibodies were directed to the conserved stem region of HA and were also elicited in nonhuman primates. Cross-neutralization of H1N1 subtypes elicited by this approach provides a basis for the development of a universal influenza vaccine for humans. PMID:20647428

  17. Energy conservation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Courtright, H.A. [Electric Power Research Inst., Palo Alto, CA (United States)

    1993-12-31

    The conservation of energy through the efficiency improvement of existing end-uses and the development of new technologies to replace less efficient systems is an important component of the overall effort to reduce greenhouse gases which may contribute to global climate change. Even though uncertainties exist on the degree and causes of global warming, efficiency improvements in end-use applications remain in the best interest of utilities, their customers and society because efficiency improvements not only reduce environmental exposures but also contribute to industrial productivity, business cost reductions and consumer savings in energy costs.

  18. Integrating Agriculture and Conservation

    Science.gov (United States)

    Vandever, Mark W.

    2010-01-01

    The USGS produces the needed science-based information to guide management actions and policy decisions that support wildlife habitat and other environmental services compatible with USDA conservation goals and farm operations. The Policy Analysis and Science Assistance Branch of the Fort Collins Science Center (FORT) has conducted research involving a national landowner survey and numerous short- and long-term evaluations regarding vegetation responses to land management practices. This research helps land and resource managers to make informed decisions and resolve resource management conflicts.

  19. New electromagnetic conservation laws

    International Nuclear Information System (INIS)

    The Chevreton superenergy tensor was introduced in 1964 as a counterpart, for electromagnetic fields, of the well-known Bel-Robinson tensor of the gravitational field. We here prove the unnoticed facts that, in the absence of electromagnetic currents, Chevreton's tensor (i) is completely symmetric, and (ii) has a trace-free divergence if the Einstein-Maxwell equations hold. It follows that the trace of the Chevreton tensor is a rank-2, symmetric, trace-free, conserved tensor, which is different from the energy-momentum tensor, and nonetheless can be constructed for any test Maxwell field or any Einstein-Maxwell spacetime

  20. Hearing Conservation Live #2430

    Energy Technology Data Exchange (ETDEWEB)

    Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    Occupational hearing loss is one of the most common work-related illnesses in the United States (US). From 22 to 30 million US workers are exposed to hazardous noise levels at work, and 25% of these workers will develop permanent hearing loss. Hearing loss from noise is slow and painless, and you can have a disability before you notice it. This course presents the hazards associated with workplace noise, the purpose and elements of the Los Alamos National Laboratory (LANL) Hearing Conservation Program (HCP), and controls that are available to reduce your exposure to hazardous levels of noise.

  1. Use of Sindbis virus-mediated RNA interference to demonstrate a conserved role of Broad-Complex in insect metamorphosis

    Czech Academy of Sciences Publication Activity Database

    Uhlířová, Miroslava; Foy, B. D.; Beaty, B. J.; Olson, K. E.; Riddiford, L. M.; Jindra, Marek

    2003-01-01

    Roč. 100, č. 26 (2003), s. 15607-15612. ISSN 0027-8424 R&D Projects: GA AV ČR IAA5007305 Institutional research plan: CEZ:AV0Z5007907 Keywords : Green fluorescent protein-steroid-hormone ecdysone Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 10.272, year: 2003

  2. Structural Basis for Recognition of Human Enterovirus 71 by a Bivalent Broadly Neutralizing Monoclonal Antibody.

    Science.gov (United States)

    Ye, Xiaohua; Fan, Chen; Ku, Zhiqiang; Zuo, Teng; Kong, Liangliang; Zhang, Chao; Shi, Jinping; Liu, Qingwei; Chen, Tan; Zhang, Yingyi; Jiang, Wen; Zhang, Linqi; Huang, Zhong; Cong, Yao

    2016-03-01

    Enterovirus 71 (EV71) is the main pathogen responsible for hand, foot and mouth disease with severe neurological complications and even death in young children. We have recently identified a highly potent anti-EV71 neutralizing monoclonal antibody, termed D5. Here we investigated the structural basis for recognition of EV71 by the antibody D5. Four three-dimensional structures of EV71 particles in complex with IgG or Fab of D5 were reconstructed by cryo-electron microscopy (cryo-EM) single particle analysis all at subnanometer resolutions. The most critical EV71 mature virion-Fab structure was resolved to a resolution of 4.8 Å, which is rare in cryo-EM studies of virus-antibody complex so far. The structures reveal a bivalent binding pattern of D5 antibody across the icosahedral 2-fold axis on mature virion, suggesting that D5 binding may rigidify virions to prevent their conformational changes required for subsequent RNA release. Moreover, we also identified that the complementary determining region 3 (CDR3) of D5 heavy chain directly interacts with the extremely conserved VP1 GH-loop of EV71, which was validated by biochemical and virological assays. We further showed that D5 is indeed able to neutralize a variety of EV71 genotypes and strains. Moreover, D5 could potently confer protection in a mouse model of EV71 infection. Since the conserved VP1 GH-loop is involved in EV71 binding with its uncoating receptor, the scavenger receptor class B, member 2 (SCARB2), the broadly neutralizing ability of D5 might attribute to its inhibition of EV71 from binding SCARB2. Altogether, our results elucidate the structural basis for the binding and neutralization of EV71 by the broadly neutralizing antibody D5, thereby enhancing our understanding of antibody-based protection against EV71 infection. PMID:26938634

  3. Structural Basis for Recognition of Human Enterovirus 71 by a Bivalent Broadly Neutralizing Monoclonal Antibody.

    Directory of Open Access Journals (Sweden)

    Xiaohua Ye

    2016-03-01

    Full Text Available Enterovirus 71 (EV71 is the main pathogen responsible for hand, foot and mouth disease with severe neurological complications and even death in young children. We have recently identified a highly potent anti-EV71 neutralizing monoclonal antibody, termed D5. Here we investigated the structural basis for recognition of EV71 by the antibody D5. Four three-dimensional structures of EV71 particles in complex with IgG or Fab of D5 were reconstructed by cryo-electron microscopy (cryo-EM single particle analysis all at subnanometer resolutions. The most critical EV71 mature virion-Fab structure was resolved to a resolution of 4.8 Å, which is rare in cryo-EM studies of virus-antibody complex so far. The structures reveal a bivalent binding pattern of D5 antibody across the icosahedral 2-fold axis on mature virion, suggesting that D5 binding may rigidify virions to prevent their conformational changes required for subsequent RNA release. Moreover, we also identified that the complementary determining region 3 (CDR3 of D5 heavy chain directly interacts with the extremely conserved VP1 GH-loop of EV71, which was validated by biochemical and virological assays. We further showed that D5 is indeed able to neutralize a variety of EV71 genotypes and strains. Moreover, D5 could potently confer protection in a mouse model of EV71 infection. Since the conserved VP1 GH-loop is involved in EV71 binding with its uncoating receptor, the scavenger receptor class B, member 2 (SCARB2, the broadly neutralizing ability of D5 might attribute to its inhibition of EV71 from binding SCARB2. Altogether, our results elucidate the structural basis for the binding and neutralization of EV71 by the broadly neutralizing antibody D5, thereby enhancing our understanding of antibody-based protection against EV71 infection.

  4. The sub-millimeter properties of broad absorption line quasars

    OpenAIRE

    Willott, Chris J.; Rawlings, Steve; Grimes, Jennifer A.

    2003-01-01

    We have carried out the first systematic survey of the sub-millimeter properties of broad absorption line (BAL) quasars. 30 BAL quasars drawn from a homogeneously selected sample from the Sloan Digital Sky Survey at redshifts 2 3 sigma significance. The far-infrared luminosities of these quasars are > 10^{13} L_solar. There is no correlation of sub-millimeter flux with either the strength of the broad absorption feature or with absolute magnitude in our sample. We compare the sub-millimeter f...

  5. Analysis of fuel system technology for broad property fuels

    Science.gov (United States)

    Coffinberry, G. A.

    1984-01-01

    An analytical study was performed in order to assess relative performance and economic factors involved with alternative advanced fuel systems for future commercial aircraft operating with broad property fuels. Significant results, with emphasis on design practicality from the engine manufacturer' standpoint, are highlighted. Several advanced fuel systems were modeled to determine as accurately as possible the relative merits of each system from the standpoint of compatibility with broad property fuel. Freezing point, thermal stability, and lubricity were key property issues. A computer model was formulated to determine the investment incentive for each system. Results are given.

  6. Broad-band hard X-ray reflectors

    DEFF Research Database (Denmark)

    Joensen, K.D.; Gorenstein, P.; Hoghoj, P.;

    1997-01-01

    Interest in optics for hard X-ray broad-band application is growing. In this paper, we compare the hard X-ray (20-100 keV) reflectivity obtained with an energy-dispersive reflectometer, of a standard commercial gold thin-film with that of a 600 bilayer W/Si X-ray supermirror. The reflectivity of...... that of the gold, Various other design options are discussed, and we conclude that continued interest in the X-ray supermirror for broad-band hard X-ray applications is warranted....

  7. Development of broad-view camera unit for laparoscopic surgery.

    Science.gov (United States)

    Kawahara, Tomohiro; Takaki, Takeshi; Ishii, Idaku; Okajima, Masazumi

    2009-01-01

    A disadvantage of laparoscopic surgery is the narrow operative field provided by the endoscope camera. This paper describes a newly developed broad-view camera unit for use with the Broad-View Camera System, which is capable of providing a wider view of the internal organs during laparoscopic surgery. The developed camera unit is composed of a miniature color CMOS camera, an indwelling needle, and an extra-thin connector. The specific design of the camera unit and the method for positioning it are shown. The performance of the camera unit has been confirmed through basic and animal experiments. PMID:19963983

  8. Conserved upstream open reading frames in higher plants

    Directory of Open Access Journals (Sweden)

    Schultz Carolyn J

    2008-07-01

    Full Text Available Abstract Background Upstream open reading frames (uORFs can down-regulate the translation of the main open reading frame (mORF through two broad mechanisms: ribosomal stalling and reducing reinitiation efficiency. In distantly related plants, such as rice and Arabidopsis, it has been found that conserved uORFs are rare in these transcriptomes with approximately 100 loci. It is unclear how prevalent conserved uORFs are in closely related plants. Results We used a homology-based approach to identify conserved uORFs in five cereals (monocots that could potentially regulate translation. Our approach used a modified reciprocal best hit method to identify putative orthologous sequences that were then analysed by a comparative R-nomics program called uORFSCAN to find conserved uORFs. Conclusion This research identified new genes that may be controlled at the level of translation by conserved uORFs. We report that conserved uORFs are rare (

  9. Whereto with institutions and governance challenges in African wildlife conservation?

    Science.gov (United States)

    Muchapondwa, Edwin; Stage, Jesper

    2015-09-01

    African wildlife conservation has been transformed, shifting from a traditional, state-managed government approach to a broader governance approach with a wide range of actors designing and implementing wildlife policy. The most widely popularized approach has been that of community-managed nature conservancies. The knowledge of how institutions function in relation to humans and their use of the environment is critical to the design and implementation of effective conservation. This paper seeks to review the institutional and governance challenges faced in wildlife conservation in southern and eastern Africa. We discuss two different sets of challenges related to the shift in conservation practices: the practical implementation of wildlife governance, and the capacity of current governance structures to capture and distribute economic benefits from wildlife. To some extent, the issues raised by the new policies must be resolved through theoretical and empirical research addressed at wildlife conservation per se. However, many of these issues apply more broadly to a wide range of policy arenas and countries where similar policy shifts have taken place.

  10. Bonneville Power Administration`s Commercial Sector Conservation Market.

    Energy Technology Data Exchange (ETDEWEB)

    Gordan, Frederick M. [Pacific Energy Associates, Inc. (United States)

    1992-11-10

    Bonneville has, as part of its resource plan, accepted targets for commercial conservation which are quite ambitious. To meet these targets, Bonneville will need to acquire as much cost-effective conservation as possible over the next twelve years. With this in mind, this document explores the relative importance of different commercial market segments and the types of assistance each market needs to install as many cost-effective conservation measures in as many buildings as possible. This document reviews Bonneville`s marketing environment and position, and suggests goals for commercial sector conservation marketing at Bonneville. Then it presents a broad market segmentation and series of additional demographic analyses. These analyses assess what groups of consumers Bonneville must reach to achieve most of the commercial conservation potential and what is needed to reach them. A final section reviews the success of Bonneville programs at reaching various markets. The market segmentation identifies different types of consumers and opportunities which would require distinct program approaches. Four large market segments are identified that have distinct program needs. Then four ``building life-cycle events`` are identified which provide important conservation opportunities and also require distinct program services. This creates a matrix of 16 cells which delineate distinct needs for program marketing. Each of the four key market segments manages at least 20% of the Region`s commercial floorspace.

  11. Selling energy conservation.

    Science.gov (United States)

    Hinrichsen, D

    1995-01-01

    This article concerns the Organization of the Petroleum Exporting Countries (OPEC) crisis and its impact on energy efficiency measures in the US. In 1985, when the OPEC collapsed, the US government had avoided the need to construct 350 gigawatts of new electric capacity. The most successful efficiency improvements, especially in household appliances and equipment, lighting and tightened energy efficiency standards in new buildings, resulted from the OPEC event. The real innovation of that time was the change in profit rules for utilities. This revolution and the way some US utilities view energy have not caught on elsewhere. Despite the initiative toward improving energy efficiency in homes, offices and industries, the change has been slow. Partly to blame are the big development banks, which pointed out that short-term conservation and efficiency measures could save at least 15% of the total energy demand without the need for major investment. The benefits of energy conservation was shown during the oil shock when per capita energy consumption fell by 5% in the member states of the Organization of Economic Cooperation and Development, while the per capita gross domestic product grew by a third. There has been a decrease in energy expenditure worldwide, and the scope for further energy savings is enormous, but governments need to recognize and seize the opportunity. PMID:12295818

  12. Integrable viscous conservation laws

    Science.gov (United States)

    Arsie, Alessandro; Lorenzoni, Paolo; Moro, Antonio

    2015-06-01

    We propose an extension of the Dubrovin-Zhang perturbative approach to the study of normal forms for non-Hamiltonian integrable scalar conservation laws. The explicit computation of the first few corrections leads to the conjecture that such normal forms are parameterized by one single functional parameter, named the viscous central invariant. A constant valued viscous central invariant corresponds to the well-known Burgers hierarchy. The case of a linear viscous central invariant provides a viscous analog of the Camassa-Holm equation, that formerly appeared as a reduction of two-component Hamiltonian integrable systems. We write explicitly the negative and positive hierarchy associated with this equation and prove the integrability showing that they can be mapped respectively into the heat hierarchy and its negative counterpart, named the Klein-Gordon hierarchy. A local well-posedness theorem for periodic initial data is also proven. We show how transport equations can be used to effectively construct asymptotic solutions via an extension of the quasi-Miura map that preserves the initial datum. The method is alternative to the method of the string equation for Hamiltonian conservation laws and naturally extends to the viscous case. Using these tools we derive the viscous analog of the Painlevé I2 equation that describes the universal behaviour of the solution at the critical point of gradient catastrophe.

  13. Chronic toxicity of contaminated sediments on reproduction and histopathology of the crustacean Gammarus fossarum and relationship with the chemical contamination and in vitro effects

    Energy Technology Data Exchange (ETDEWEB)

    Mazurova, Edita; Hilscherova, Klara; Sidlova-Stepankova, Tereza; Blaha, Ludek [Faculty of Science, RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk Univ., Brno (Czech Republic); Koehler, Heinz R. [Animal Physiological Ecology, Univ. of Tuebingen (Germany); Triebskorn, Rita [Steinbeis-Transfer Center for Ecotoxicology and Ecophysiology, Rottenburg (Germany); Jungmann, Dirk [Inst. of Hydrobiology, Dresden Univ. of Tech. (Germany); Giesy, John P. [Dept. of Veterinary Biomedical Sciences and Toxicology Centre, Univ. of Saskatchewan, Saskatoon (Canada); Zoology Dept., National Food Safety and Toxicology Center, and Center for Integrative Toxicology Center, and Center for Integrative Toxicology, Michigan State Univ., East Lansing, MI (United States); Biology and Chemistry Dept., City Univ. of Hong Kong, Kowloon, Hong Kong (China); School of the Environment, Nanjing Univ. (China)

    2010-04-15

    The aim of the present study was to investigate possible relationships between the sediment contaminants and the occurrence of intersex in situ. Two of the studied sediments were from polluted sites with increased occurrence of intersex crustaceans (Lake Pilnok, black coal mining area in the Czech Republic, inhabited by the crayfish Pontastacus leptodactylus population with 18% of intersex; creek Lockwitzbach in Germany with Gammarus fossarum population with about 7% of intersex). Materials and methods Sediments were studied by a combined approach that included (1) determination of concentrations of metals and traditionally analyzed organic pollutants such as polychlorinated biphenyls, pesticides, and polycyclic aromatic hydrocarbons (PAHs); (2) examination of the in vitro potencies to activate aryl hydrocarbon (AhR), estrogen (ER), and androgen receptor-mediated responses; and (3) in vivo whole sediment exposures during a 12-week reproduction toxicity study with benthic amphipod G. fossarum. (orig.)

  14. Deep-Sea decapod crustaceans (Caridea, Polychelida, Anomura and Brachyura) collected from the Nikko Seamounts, Mariana Arc, using a remotely operated vehicle "Hyper-Dolphin".

    Science.gov (United States)

    Komai, Tomoyuki; Tsuchida, Shinji

    2014-01-01

    Samples and images of deep-water benthic decapod crustaceans were collected from the Nikko Seamounts, Mariana Arc, at depths of 520-680 m, by using the remotely operate vehicle "Hyper-Dolphin", equipped with a high definition camera, digital camera, manipulators and slurp gun (suction sampler). The following seven species were collected, of which three are new to science: Plesionika unicolor n. sp. (Caridea: Pandalidae), Homeryon armarium Galil, 2000 (Polychelida: Polychelidae), Eumunida nikko n. sp. (Anomura: Eumunididae), Michelopagurus limatulus (Henderson, 1888) (Anomura: Paguridae), Galilia petricola n. sp. (Brachyura: Leucosiidae), Cyrtomaia micronesica Richer de Forges & Ng, 2007 (Brachyura: Inachidae), and Progeryon mus Ng & Guinot, 1999 (Brachyura: Progeryonidae). Affinities of these three new species are discussed. All but H. armarium are recorded from the Japanese Exclusive Economic Zone for the first time. Brief notes on ecology and/or behavior are given for each species. PMID:24870636

  15. Partners in amphibian and reptile conservation 2013 annual report

    Science.gov (United States)

    Conrad, Paulette M., (Edited By); Weir, Linda A.; Nanjappa, Priya

    2014-01-01

    Partners in Amphibian and Reptile Conservation (PARC) was established in 1999 to address the widespread declines, extinctions, and range reductions of amphibians and reptiles, with a focus on conservation of taxa and habitats in North America. Amphibians and reptiles are affected by a broad range of human activities, both as incidental effects of habitat alteration and direct effect from overexploitation; these animals are also challenged by the perception that amphibians and reptiles are either dangerous or of little environmental or economic value. However, PARC members understand these taxa are important parts of our natural an cultural heritage and they serve important roles in ecosystems throughout the world. With many amphibians and reptiles classified as threatened with extinction, conservation of these animals has never been more important.

  16. A horizon scan for species conservation by zoos and aquariums.

    Science.gov (United States)

    Gusset, Markus; Fa, John E; Sutherland, William J

    2014-01-01

    We conducted the first horizon scan for zoos and aquariums to identify the 10 most important emerging issues for species conservation. This involved input from more than 100 experts from both the wider conservation community and the world zoo and aquarium community. Some of the issues are globally important: diseases, zoonoses, and biosecurity issues; new (communication) technologies; global water shortage and food insecurity; developing economies and markets for wildlife consumption; changes in wildlife population dynamics; and political instability and conflicts. Other issues are more specific to zoos and aquariums: need for extractive reserves; space shortage in zoos and aquariums; need for metapopulation management; and demand for caring of more species in zoos and aquariums. We also identified some broad approaches to these issues. Addressing the emerging issues identified in our horizon scan will further increase the contribution of the world zoo and aquarium community to global biodiversity conservation. PMID:25065560

  17. Nucleotide Base Variation of Blast Disease Resistance Gene Pi33 in Rice Selected Broad Genetic Background

    Directory of Open Access Journals (Sweden)

    DWINITA WIKAN UTAMI

    2011-09-01

    Full Text Available Rice is one of the most important crops for human beings, thus increasing productivity are continually persecuted. Blast disease can reduce the rate of productivity of rice cultivation. Therefore, the program of blast disease-resistant varieties needs to do effectively. One of broad-spectrum blast disease-resistant gene is Pi33. This study was aimed to identify the variation in the sequence of nucleotide bases of Pi33 gene in five interspesific lines which derived from Bio46 (IR64/Oryza rufipogon and CT13432 crossing. DNA of five rice lines were amplified using the spesific primer for Pi33, G1010. Amplification results purified through Exonuclease 1 and Shrimp Alkaline Phosphatase protocols. Labelling using fluorescent dyes done before sequencing nucleotide base using CEQ8000 instrument. The results showed that lines number 28 showed introgesion of the three control parent genome (subspecies of Indica, subspecies of Japonica, and O. rufipogon while the Lines number 79, 136, and 143 were identical to Indica genome. Strain number 195 was identical to Japonica genome. These broad genetic background lines promise as durable performance to attack the expansion of the dynamic nature of the pathogen to blast. The result of ortholog sequence analysis found conserved nucleotide base sequence (CAGCAGCC which involved in heterotrimeric G-protein group. This protein has role as plant receptor for recognizing pathogen elicitor in interaction of rice and blast pathogen.

  18. Fast symplectic mapping and long-term stability near broad resonances

    International Nuclear Information System (INIS)

    Fast symplectic mapping, based on a canonical generator of the full-turn map in polar coordinates (I, Φ), is a powerful tool to study long-term stability in large hadron storage rings. Accurate maps for realistic lattices can be constructed in a few hours on a workstation computer, and can be iterated to follow orbits for 107 turns in less than 4 hours. Orbits of the map can also be used in a non-perturbative construction of quasi-invariant actions. By bounding the small changes in quasi-invariants along many short orbits, one can derive conservative estimates of survival time for long orbits, for any initial condition in a region of phase space. A first quasi-invariant vector, J, arises from a canonical transformation (1, Φ) → (J, Ψ), based on interpolation of invariant tori surrounding the origin. The variation of J is relatively large near a broad resonance. In such a region a second canonical transformation, associated with pendulum-like motion in appropriate variables, is required to produce a good quasi-invariant. This quasi-invariant is used to set a long-term bound on motion near a broad, large-amplitude resonance in a realistic model of the Large Hadron Collider (LHC). Interesting general properties of the pseudo-pendulum motion are studied

  19. The molecular basis for the broad substrate specificity of human sulfotransferase 1A1.

    Directory of Open Access Journals (Sweden)

    Ilana Berger

    Full Text Available Cytosolic sulfotransferases (SULTs are mammalian enzymes that detoxify a wide variety of chemicals through the addition of a sulfate group. Despite extensive research, the molecular basis for the broad specificity of SULTs is still not understood. Here, structural, protein engineering and kinetic approaches were employed to obtain deep understanding of the molecular basis for the broad specificity, catalytic activity and substrate inhibition of SULT1A1. We have determined five new structures of SULT1A1 in complex with different acceptors, and utilized a directed evolution approach to generate SULT1A1 mutants with enhanced thermostability and increased catalytic activity. We found that active site plasticity enables binding of different acceptors and identified dramatic structural changes in the SULT1A1 active site leading to the binding of a second acceptor molecule in a conserved yet non-productive manner. Our combined approach highlights the dominant role of SULT1A1 structural flexibility in controlling the specificity and activity of this enzyme.

  20. Broadly Neutralizing Alphavirus Antibodies Bind an Epitope on E2 and Inhibit Entry and Egress.

    Science.gov (United States)

    Fox, Julie M; Long, Feng; Edeling, Melissa A; Lin, Hueylie; van Duijl-Richter, Mareike K S; Fong, Rachel H; Kahle, Kristen M; Smit, Jolanda M; Jin, Jing; Simmons, Graham; Doranz, Benjamin J; Crowe, James E; Fremont, Daved H; Rossmann, Michael G; Diamond, Michael S

    2015-11-19

    We screened a panel of mouse and human monoclonal antibodies (MAbs) against chikungunya virus and identified several with inhibitory activity against multiple alphaviruses. Passive transfer of broadly neutralizing MAbs protected mice against infection by chikungunya, Mayaro, and O'nyong'nyong alphaviruses. Using alanine-scanning mutagenesis, loss-of-function recombinant proteins and viruses, and multiple functional assays, we determined that broadly neutralizing MAbs block multiple steps in the viral lifecycle, including entry and egress, and bind to a conserved epitope on the B domain of the E2 glycoprotein. A 16 Å resolution cryo-electron microscopy structure of a Fab fragment bound to CHIKV E2 B domain provided an explanation for its neutralizing activity. Binding to the B domain was associated with repositioning of the A domain of E2 that enabled cross-linking of neighboring spikes. Our results suggest that B domain antigenic determinants could be targeted for vaccine or antibody therapeutic development against multiple alphaviruses of global concern. PMID:26553503

  1. Assessment of radionuclide concentration in three crustaceans species of the bay of Bengal; Mesure de la concentration de radionucleides dans trois especes de crustaces du golfe du Bengale

    Energy Technology Data Exchange (ETDEWEB)

    Hasan, C.K.; Zafar, M. [Chittagong Univ., Institute of Marine Sciences (Bangladesh); Chowdhury, M.I.; Kamal, M. [Radioactivity Testing and Monitoring Laboratory, Bangladesh Atomic Energy Commission, Chittagong (Bangladesh)

    2006-10-15

    The natural ({sup 226}Ra, {sup 228}Th, {sup 232}Th and {sup 40}K) and anthropogenic ({sup 137}Cs) radionuclides concentrations in three crustaceans species (Penaeus monodon, Metapenaeus monoceros and Panulirus versicolor), collected from the bay of Bengal, were determined with an aim of assessing any internal radiation hazard due to consumption of the shell fishes and establishing a database for radioactivity levels of the species. Very low level of radioactivity was observed in all the species. The average activity of {sup 226}Ra observed in P. monodon was 1.21 {+-} 0.27 Bq kg{sup -1} fw; in M. monoceros was 0.70 {+-}0.08 Bq kg{sup -1} fw, and in Panulirus versicolor was 1.04 {+-} 0.09 Bq kg{sup -1} fw. The activity of {sup 232}Th observed in these species was 1.30 {+-} 0.37, 0.76 {+-} 0.34 and 1.32 {+-} 0.70 Bq kg{sup -1} fw, and {sup 228}Th was 0.55 {+-} 0.26, 0.31 {+-} 0.14 and 0.74 {+-} 0.22 Bq kg{sup -1} fw, respectively. The average activity of {sup 40}K observed in these species was 12.56 {+-} 1.18, 6.38 {+-}1.02 and 10.07 {+-} 1.52 Bq kg{sup -1} fw, respectively. The activity of radiocaesium ({sup 137}Cs) was below detection limit. The results indicate that the natural and artificial radionuclides observed in three crustaceans species are safe for human health. A significant relationship was observed between {sup 226}Ra and {sup 232}Th in both the P. monodon (r = 0.839, p {<=} 0.05, df = 4) and the Panulirus versicolor (r = 0.906, p {<=} 0.05, df = 4). (authors)

  2. Crecimiento en crustáceos decápodos: resultados de investigaciones realizadas en Argentina Growth of decapod crustaceans: results of research made on Argentine species

    Directory of Open Access Journals (Sweden)

    Ana M. Petriella

    1997-01-01

    Full Text Available trabajo se refiere a los aspectos biológicos del crecimiento y a los métodos empleados para estudiar el aumento de tamaño en los crustáceos Decápodos del mar epicontinental argentino. Primeramente se reseñan los mecanismos endócrinos que controlan y desencadenan la muda. Luego se describen las características distintivas del crecimiento en los crustáceos, que se produce en forma discontinua y sujeto a las sucesivas mudas (cambio del exoesqueleto. Se mencionan los métodos usados por distintos autores, especialmente los referidos a especies argentinas, incluyendo algunos de los métodos cuantitativos empleados en Argentina para analizar el crecimiento. Se presentan ejemplos sobre el dimorfismo sexual y caracteres sexuales secundarios permanentes o transitorios relacionados con el ciclo reproductivo de algunas especies. Finalmente, se destaca la influencia de las condiciones ambientales (temperatura, salinidad, contaminación y de otros factores tales como la nutrición, la pérdida de apéndices y el parasitismo sobre el crecimientoThe paper deals with the aspect related to the growth and methods used to estimate the size and weight increment of the Decapod crustaceans in the Argentine Sea (Southwest Atlantic Ocean. At first are mentioned the endocrine mechanism which promote and control the molting cycle. Comments are made on the characteristcs of the discontinuous growth in crustaceans, depending on successive moults, i.e. changes of the exoskeleton. Details are given of the methods used by different authors, especially those on argentine species, including some methods quantitative of analysis of growth. Examples are given for sexual dimorphism and secondary sexual characters, permanent or transitory, which are related to the reproductive cycle in some species. Finally, influences of environmental conditions on growth are reviewed: temperature, ligth, salinity, pressure, pollution and other factor related to nutrition, limb loss, and

  3. Transcriptome dynamics of a broad host-range cyanophage and its hosts.

    Science.gov (United States)

    Doron, Shany; Fedida, Ayalla; Hernández-Prieto, Miguel A; Sabehi, Gazalah; Karunker, Iris; Stazic, Damir; Feingersch, Roi; Steglich, Claudia; Futschik, Matthias; Lindell, Debbie; Sorek, Rotem

    2016-06-01

    Cyanobacteria are highly abundant in the oceans and are constantly exposed to lytic viruses. The T4-like cyanomyoviruses are abundant in the marine environment and have broad host-ranges relative to other cyanophages. It is currently unknown whether broad host-range phages specifically tailor their infection program for each host, or employ the same program irrespective of the host infected. Also unknown is how different hosts respond to infection by the same phage. Here we used microarray and RNA-seq analyses to investigate the interaction between the Syn9 T4-like cyanophage and three phylogenetically, ecologically and genomically distinct marine Synechococcus strains: WH7803, WH8102 and WH8109. Strikingly, Syn9 led a nearly identical infection and transcriptional program in all three hosts. Different to previous assumptions for T4-like cyanophages, three temporally regulated gene expression classes were observed. Furthermore, a novel regulatory element controlled early-gene transcription, and host-like promoters drove middle gene transcription, different to the regulatory paradigm for T4. Similar results were found for the P-TIM40 phage during infection of Prochlorococcus NATL2A. Moreover, genomic and metagenomic analyses indicate that these regulatory elements are abundant and conserved among T4-like cyanophages. In contrast to the near-identical transcriptional program employed by Syn9, host responses to infection involved host-specific genes primarily located in hypervariable genomic islands, substantiating islands as a major axis of phage-cyanobacteria interactions. Our findings suggest that the ability of broad host-range phages to infect multiple hosts is more likely dependent on the effectiveness of host defense strategies than on differential tailoring of the infection process by the phage. PMID:26623542

  4. Broad-Band Spectroscopy of Hercules X-1 with Suzaku

    Science.gov (United States)

    Asami, Fumi; Enoto, Teruaki; Iwakiri, Wataru; Yamada, Shin'ya; Tamagawa, Toru; Mihara, Tatehiro; Nagase, Fumiaki

    2014-01-01

    Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4- 100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.

  5. Document understanding for a broad class of documents

    NARCIS (Netherlands)

    Aiello, Marco; Monz, Christof; Todoran, Leon; Worring, Marcel

    2002-01-01

    We present a document analysis system able to assign logical labels and extract the reading order in a broad set of documents. All information sources, from geometric features and spatial relations to the textual features and content are employed in the analysis. To deal effectively with these infor

  6. Broad-Area Laser Diode With Fiber-Optic Injection

    Science.gov (United States)

    Hazel, Geoffrey; Mead, Patricia; Davis, Christopher; Cornwell, Donald

    1992-01-01

    Fiber-optic injection-locked broad-area laser diode features single-mode output via fiber-optic injection and serves as compact, rugged, high-power near-infrared source. Useful in free-space and fiber-optic communication links, as communication-receiver preamplifier, and pump source for solid-state lasers.

  7. Silver Nanoparticles with Broad Multiband Linear Optical Absorption

    KAUST Repository

    Bakr, Osman M.

    2009-07-06

    A simple one-pot method produces silver nanoparticles coated with aryl thiols that show intense, broad nonplasmonic optical properties. The synthesis works with many aryl-thiol capping ligands, including water-soluble 4-mercaptobenzoic acid. The nanoparticles produced show linear absorption that is broader, stronger, and more structured than most conventional organic and inorganic dyes.

  8. Children and trauma : a broad perspective on exposure and recovery

    NARCIS (Netherlands)

    Alisic, E.

    2011-01-01

    The purpose of this dissertation was to generate a broad overview of children’s exposure to and recovery from trauma in order to promote theory building and the design of prevention and intervention activities. First, a general population study was conducted in 1770 primary school children. They fil

  9. Dusty origin of the Broad Line Region in active galaxies

    CERN Document Server

    Czerny, Bozena; Kaluzny, Janusz; Maity, Ishita

    2012-01-01

    The most characteristic property of active galaxies, including quasars, are prominent broad emission lines. I will discuss an interesting possibility that dust is responsible for this phenomenon. The dust is known to be present in quasars in the form of a dusty/molecular torus which results in complexity of the appearance of active galaxies. However, this dust is located further from the black hole than the Broad Line Region. We propose that the dust is present also closer in and it is actually responsible for formation of the broad emission lines. The argument is based on determination of the temperature of the disk atmosphere underlying the Broad Line Region: it is close to 1000 K, independently from the black hole mass and accretion rate of the object. The mechanism is simple and universal but leads to a considerable complexity of the active nucleus surrounding. The understanding the formation of BLR opens a way to use it reliably - in combination with reverberation measurement of its size - as standard ca...

  10. Highly conserved influenza A virus epitope sequences as candidates of H3N2 flu vaccine targets.

    Science.gov (United States)

    Wu, Ko-Wen; Chien, Chih-Yi; Li, Shiao-Wen; King, Chwan-Chuen; Chang, Chuan-Hsiung

    2012-08-01

    This study focused on identifying the conserved epitopes in a single subtype A (H3N2)-as candidates for vaccine targets. We identified a total of 32 conserved epitopes in four viral proteins [22 HA, 4PB1, 3 NA, 3 NP]. Evaluation of conserved epitopes in coverage during 1968-2010 revealed that (1) 12 HA conserved epitopes were highly present in the circulating viruses; (2) the remaining 10 HA conserved epitopes appeared with lower percentage but a significantly increasing trend after 1989 [p<0.001]; and (3) the conserved epitopes in NA, NP and PB1 are also highly frequent in wild-type viruses. These conserved epitopes also covered an extremely high percentage of the 16 vaccine strains during the 42 year period. The identification of highly conserved epitopes using our approach can also be applied to develop broad-spectrum vaccines. PMID:22698979

  11. Putting beta-diversity on the map: broad-scale congruence and coincidence in the extremes.

    Directory of Open Access Journals (Sweden)

    Meghan W McKnight

    2007-10-01

    Full Text Available Beta-diversity, the change in species composition between places, is a critical but poorly understood component of biological diversity. Patterns of beta-diversity provide information central to many ecological and evolutionary questions, as well as to conservation planning. Yet beta-diversity is rarely studied across large extents, and the degree of similarity of patterns among taxa at such scales remains untested. To our knowledge, this is the first broad-scale analysis of cross-taxon congruence in beta-diversity, and introduces a new method to map beta-diversity continuously across regions. Congruence between amphibian, bird, and mammal beta-diversity in the Western Hemisphere varies with both geographic location and spatial extent. We demonstrate that areas of high beta-diversity for the three taxa largely coincide, but areas of low beta-diversity exhibit little overlap. These findings suggest that similar processes lead to high levels of differentiation in amphibian, bird, and mammal assemblages, while the ecological and biogeographic factors influencing homogeneity in vertebrate assemblages vary. Knowledge of beta-diversity congruence can help formulate hypotheses about the mechanisms governing regional diversity patterns and should inform conservation, especially as threat from global climate change increases.

  12. Steps toward broad-spectrum therapeutics: discovering virulence-associated genes present in diverse human pathogens

    Directory of Open Access Journals (Sweden)

    de Rochefort Anna

    2009-10-01

    Full Text Available Abstract Background New and improved antimicrobial countermeasures are urgently needed to counteract increased resistance to existing antimicrobial treatments and to combat currently untreatable or new emerging infectious diseases. We demonstrate that computational comparative genomics, together with experimental screening, can identify potential generic (i.e., conserved across multiple pathogen species and novel virulence-associated genes that may serve as targets for broad-spectrum countermeasures. Results Using phylogenetic profiles of protein clusters from completed microbial genome sequences, we identified seventeen protein candidates that are common to diverse human pathogens and absent or uncommon in non-pathogens. Mutants of 13 of these candidates were successfully generated in Yersinia pseudotuberculosis and the potential role of the proteins in virulence was assayed in an animal model. Six candidate proteins are suggested to be involved in the virulence of Y. pseudotuberculosis, none of which have previously been implicated in the virulence of Y. pseudotuberculosis and three have no record of involvement in the virulence of any bacteria. Conclusion This work demonstrates a strategy for the identification of potential virulence factors that are conserved across a number of human pathogenic bacterial species, confirming the usefulness of this tool.

  13. Supply Curves of Conserved Energy

    Energy Technology Data Exchange (ETDEWEB)

    Meier, Alan Kevin

    1982-05-01

    Supply curves of conserved energy provide an accounting framework that expresses the potential for energy conservation. The economic worthiness of a conservation measure is expressed in terms of the cost of conserved energy, and a measure is considered economical when the cost of conserved energy is less than the price of the energy it replaces. A supply curve of conserved energy is independent of energy prices; however, the economical reserves of conserved energy will depend on energy prices. Double-counting of energy savings and error propagation are common problems when estimating conservation potentials, but supply curves minimize these difficulties and make their consequences predictable. The sensitivity of the cost of conserved energy is examined, as are variations in the optimal investment strategy in response to changes in inputs. Guidelines are presented for predicting the consequences of such changes. The conservation supply curve concept can be applied to peak power, water, pollution, and other markets where consumers demand a service rather than a particular good.

  14. Information conservation and retrieval

    International Nuclear Information System (INIS)

    In this paper preliminary suggestions are given for the type of documents to be kept in a long term archive for radioactive waste. The time scale relevant for various documents is also given. It is pointed out that waste management may gain from an early identification of documents to be part of a waste archive. For the state, whose responsibility it may be necessary to think in terms of a much longer time span than is normally considered for archives. Experts in the fields of law, social science, philosophy and theory of science have been consulted for their ideas on improving strategies of record conservation and availability and to put existing strategies into perspective. Their comments are presented

  15. Conservative Noise Filters

    Directory of Open Access Journals (Sweden)

    Mona M.Jamjoom

    2016-05-01

    Full Text Available Noisy training data have a huge negative impact on machine learning algorithms. Noise-filtering algorithms have been proposed to eliminate such noisy instances. In this work, we empirically show that the most popular noise-filtering algorithms have a large False Positive (FP error rate. In other words, these noise filters mistakenly identify genuine instances as outliers and eliminate them. Therefore, we propose more conservative outlier identification criteria that improve the FP error rate and, thus, the performance of the noise filters. With the new filter, an instance is eliminated if and only if it is misclassified by a mutual decision of Naïve Bayesian (NB classifier and the original filtering criteria being used. The number of genuine instances that are incorrectly eliminated is reduced as a result, thereby improving the classification accuracy.

  16. Superradiance and flux conservation

    Science.gov (United States)

    Boonserm, Petarpa; Ngampitipan, Tritos; Visser, Matt

    2014-09-01

    The theoretical foundations of the phenomenon known as superradiance still continue to attract considerable attention. Despite many valiant attempts at pedagogically clear presentations, the effect nevertheless still continues to generate some significant confusion. Part of the confusion arises from the fact that superradiance in a quantum field theory context is not the same as superradiance (superfluorescence) in some condensed matter contexts; part of the confusion arises from traditional but sometimes awkward normalization conventions, and part is due to sometimes unnecessary confusion between fluxes and probabilities. We shall argue that the key point underlying the effect is flux conservation (and, in the presence of dissipation, a controlled amount of flux nonconservation), and that attempting to phrase things in terms of reflection and transmission probabilities only works in the absence of superradiance. To help clarify the situation we present a simple exactly solvable toy model exhibiting both superradiance and damping.

  17. Gap Analysis and Conservation Network for Freshwater Wetlands in Central Yangtze Ecoregion

    OpenAIRE

    Li Xiaowen; Zhuge Haijin; Mengdi Li

    2013-01-01

    The Central Yangtze Ecoregion contains a large area of internationally important freshwater wetlands and supports a huge number of endangered waterbirds; however, these unique wetlands and the biodiversity they support are under the constant threats of human development pressures, and the prevailing conservation strategies generated based on the local scale cannot adequately be used as guidelines for ecoregion-based conservation initiatives for Central Yangtze at the broad scale. This paper a...

  18. Symmetry, conservation laws, and theoretical particle physics

    Science.gov (United States)

    Krumins, Andris Visvaldis

    In this work, we trace the role of symmetry throughout the history of theoretical particle physics, paying particular attention to the role of group theory, the formal mathematics of symmetry. After an analysis of the role of conservation laws and invariance in the theory of general relativity, we move on to Weyl's gauge theory of 1918, which was developed within the context of general relativity as an attempt to unify gravitation and electromagnetism. Weyl was trying to exploit an invariance of scale, and although his theory was experimentally refuted, it provided a formulation of the conservation of charge. After the advent of quantum mechanics, gauge theory was reinterpreted by London as an invariance of the wave-function. Weyl and Wigner studied group theory in the context of quantum mechanics, but the broadness of its application had yet to be appreciated. Symmetry was soon exploited in the nuclear interactions, however, and we examine the events leading to the discovery of SU(2) of isotopic spin. We analyze how the discovery of strangeness was linked to the generalization of SU(2) to SU(3), and also how it led to a differentiation between the strong interactions, which conserve isotopic spin and strangeness, and the weak interactions, which violate these conservation laws, along with the conservation of parity. Yang and Mills were impressed with gauge invariance, and in 1954, they took the bold step of imposing it upon the Lagrangian of the strong interactions, forcing the introduction of three new gauge fields. There was a problem, however, because although the short-range of the strong interactions implied that these gauge bosons should be massive, they needed to be massless in order to preserve gauge invariance. In addition, efforts were made to extend Yang-Mills theory to the weak interactions, but they also faced the same zero-mass problem. This problem was finally solved in 1967, when Weinberg and Salam showed how gauge boson masses could be generated

  19. Conserving connectivity: some lessons from mountain lions in southern California.

    Science.gov (United States)

    Morrison, Scott A; Boyce, Walter M

    2009-04-01

    Habitat corridors can be essential for persistence of wildlife populations in fragmented landscapes. Although much research has focused on identifying species and places critical for conservation action, the conservation literature contains surprisingly few examples of corridors that actually have been protected and so provides little guidance for moving from planning through implementation. We examined a case study from southern California that combines monitoring of radio-collared mountain lions (Puma concolor) with an assessment of land-protection efforts to illustrate lessons learned while attempting to maintain ecological connectivity in a rapidly urbanizing landscape. As in many places, conservation scientists have provided science-based maps of where conservation efforts should focus. But implementing corridors is a business decision based not solely on ecological information but also on cost, opportunity cost, investment risk, and other feasibility considerations. Here, the type and pattern of development is such that key connections will be lost unless they are explicitly protected. Keeping pace with conversion, however, has been difficult, especially because conservation efforts have been limited to traditional parcel-by-parcel land-protection techniques. The challenges of and trade-offs in implementation make it clear that in southern California, connectivity cannot be bought one parcel at a time. Effective land-use plans and policies that incorporate conservation principles, such as California's Natural Communities Conservation Planning program, are needed to support the retention of landscape permeability. Lessons from this study have broad application, especially as a precautionary tale for places where such extensive and intensive development has not yet occurred. Given how limiting resources are for biodiversity conservation, conservationists must be disciplined about where and how they attempt corridor protection: in rapidly fragmenting landscapes

  20. Conservative Evolution, Sustainability, and Culture

    OpenAIRE

    Náray-Szabó, Gábor

    2014-01-01

    In his article "Conservative Evolution, Sustainability, and Culture" Gábor Náray-Szabó argues that evolution is conservative in the sense that throughout the history of the universe old constructs like elementary particles, amino acids, and living cells remained conserved while the world evolved/evolves in complexity. A similar process can be observed in cultural evolution as components of society and culture continue to evolve. Considering the increasing pressure on natural resources by mate...

  1. Conservation agriculture and ecosystem services

    OpenAIRE

    Dillaha, Theo A.; Cheryl B. Heatwole Shenk; Moore, Keith M.

    2010-01-01

    Conservation agriculture has many agricultural and food security benefits. In addition, conservation agriculture has potential on- and off-site ecosystem service benefits that are the focus of this paper. Ecosystem services provided by conservation agriculture fall into three main categories: provisioning services such as increased food production; regulating services such as carbon sequestration and climate regulation, reducing losses of soil, pesticides, nutrients and other potential contam...

  2. Priorities for global felid conservation.

    Science.gov (United States)

    Dickman, Amy J; Hinks, Amy E; Macdonald, Ewan A; Burnham, Dawn; Macdonald, David W

    2015-06-01

    Conservation resources are limited, necessitating prioritization of species and locations for action. Most prioritization approaches are based solely on biologically relevant characteristics of taxa or areas and ignore geopolitical realities. Doing so risks a poor return on conservation investment due to nonbiological factors, such as economic or political instability. We considered felids, a taxon which attracts intense conservation attention, to demonstrate a new approach that incorporates both intrinsic species traits and geopolitical characteristics of countries. We developed conservation priority scores for wild felids based on their International Union for Conservation of Nature status, body mass, habitat, range within protected area, evolutionary distinctiveness, and conservation umbrella potential. We used published data on governance, economics and welfare, human population pressures, and conservation policy to assign conservation-likelihood scores to 142 felid-hosting countries. We identified 71 countries as high priorities (above median) for felid conservation. These countries collectively encompassed all 36 felid species and supported an average of 96% of each species' range. Of these countries, 60.6% had below-average conservation-likelihood scores, which indicated these countries are relatively risky conservation investments. Governance was the most common factor limiting conservation likelihood. It was the major contributor to below-median likelihood scores for 62.5% of the 32 felid species occurring in lower-likelihood countries. Governance was followed by economics for which scores were below median for 25% of these species. An average of 58% of species' ranges occurred in 43 higher-priority lower-likelihood countries. Human population pressure was second to governance as a limiting factor when accounting for percentage of species' ranges in each country. As conservation likelihood decreases, it will be increasingly important to identify relevant

  3. Flow characteristics at trapezoidal broad-crested side weir

    Directory of Open Access Journals (Sweden)

    Říha Jaromír

    2015-06-01

    Full Text Available Broad-crested side weirs have been the subject of numerous hydraulic studies; however, the flow field at the weir crest and in front of the weir in the approach channel still has not been fully described. Also, the discharge coefficient of broad-crested side weirs, whether slightly inclined towards the stream or lateral, still has yet to be clearly determined. Experimental research was carried out to describe the flow characteristics at low Froude numbers in the approach flow channel for various combinations of in- and overflow discharges. Three side weir types with different oblique angles were studied. Their flow characteristics and discharge coefficients were analyzed and assessed based on the results obtained from extensive measurements performed on a hydraulic model. The empirical relation between the angle of side weir obliqueness, Froude numbers in the up- and downstream channels, and the coefficient of obliqueness was derived.

  4. Experimental evaluation of combustor concepts for burning broad property fuels

    Science.gov (United States)

    Kasper, J. M.; Ekstedt, E. E.; Dodds, W. J.; Shayeson, M. W.

    1980-01-01

    A baseline CF6-50 combustor and three advanced combustor designs were evaluated to determine the effects of combustor design on operational characteristics using broad property fuels. Three fuels were used in each test: Jet A, a broad property 13% hydrogen fuel, and a 12% hydrogen fuel blend. Testing was performed in a sector rig at true cruise and simulated takeoff conditions for the CF6-50 engine cycle. The advanced combustors (all double annular, lean dome designs) generally exhibited lower metal temperatures, exhaust emissions, and carbon buildup than the baseline CF6-50 combustor. The sensitivities of emissions and metal temperatures to fuel hydrogen content were also generally lower for the advanced designs. The most promising advanced design used premixing tubes in the main stage. This design was chosen for additional testing in which fuel/air ratio, reference velocity, and fuel flow split were varied.

  5. Broad-band characteristics of circular button pickups

    International Nuclear Information System (INIS)

    A broad-band.theory of the circular button pickup is presented. Expressions for the longitudinal and transverse transfer impedance of a pair of such pickups are derived in the frequency domain. The broad-band expressions are shown to reduce to the standard electrostatic transfer functions for wavelengths large compared to the button diameter. The theory is shown to be in reasonable agreement with measurements performed on standard LEP button electrodes. In particular, the theory explains a resonance in the response of the LEP buttons which made them unsuitable, in standard form, for their intended application as pickups in the LBL Advanced Light Source feedback system. The buttons were modified to suppress the resonance and subsequently incorporated into the feedback system

  6. Spectral Decomposition of Broad-Line AGNs and Host Galaxies

    CERN Document Server

    Vanden Berk, Daniel E; Yip, C W; Schneider, D P; Connolly, A J; Burton, R E; Jester, S; Hall, P B; Szalay, A S; Brinkmann, J; Berk, Daniel E. Vanden; Shen, Jiajian; Yip, Ching-Wa; Schneider, Donald P.; Connolly, Andrew J.; Burton, Ross E.; Jester, Sebastian; Hall, Patrick B.; Szalay, Alex S.; Brinkmann, John

    2005-01-01

    Using an eigenspectrum decomposition technique, we separate the host galaxy from the broad line active galactic nucleus (AGN) in a set of 4666 spectra from the Sloan Digital Sky Survey (SDSS), from redshifts near zero up to about 0.75. The decomposition technique uses separate sets of galaxy and quasar eigenspectra to efficiently and reliably separate the AGN and host spectroscopic components. The technique accurately reproduces the host galaxy spectrum, its contributing fraction, and its classification. We show how the accuracy of the decomposition depends upon S/N, host galaxy fraction, and the galaxy class. Based on the eigencoefficients, the sample of SDSS broad-line AGN host galaxies spans a wide range of spectral types, but the distribution differs significantly from inactive galaxies. In particular, post-starburst activity appears to be much more common among AGN host galaxies. The luminosities of the hosts are much higher than expected for normal early-type galaxies, and their colors become increasing...

  7. Diverse Broad Line Region Kinematic Signatures From Reverberation Mapping

    CERN Document Server

    Denney, K D; Pogge, R W; Adair, A; Atlee, D W; Au-Yong, K; Bentz, M C; Bird, J C; Brokofsky, D J; Chisholm, E; Comins, M L; Dietrich, M; Doroshenko, V T; Eastman, J D; Efimov, Y S; Ewald, S; Ferbey, S; Gaskell, C M; Hedrick, C H; Jackson, K; Klimanov, S A; Klimek, E S; Kruse, A K; Ladéroute, A; Lamb, J B; Leighly, K; Minezaki, T; Nazarov, S V; Onken, C A; Petersen, E A; Peterson, P; Poindexter, S; Sakata, Y; Schlesinger, K J; Sergeev, S G; Skolski, N; Stieglitz, L; Tobin, J J; Unterborn, C; Vestergaard, M; Watkins, A E; Watson, L C; Yoshii, Y

    2009-01-01

    A detailed analysis of the data from a high sampling rate, multi-month reverberation mapping campaign, undertaken primarily at MDM Observatory with supporting observations from telescopes around the world, reveals that the Hbeta emission region within the broad line regions (BLRs) of several nearby AGNs exhibit a variety of kinematic behaviors. While the primary goal of this campaign was to obtain either new or improved Hbeta reverberation lag measurements for several relatively low luminosity AGNs (presented in a separate work), we were also able to unambiguously reconstruct velocity-resolved reverberation signals from a subset of our targets. Through high cadence spectroscopic monitoring of the optical continuum and broad Hbeta emission line variations observed in the nuclear regions of NGC 3227, NGC 3516, and NGC 5548, we clearly see evidence for outflowing, infalling, and virialized BLR gas motions, respectively.

  8. Quasar Cartography: from Black Hole to Broad Line Region Scales

    CERN Document Server

    Chelouche, Doron

    2013-01-01

    A generalized approach to reverberation mapping (RM) is presented, which is applicable to broad- and narrow-band photometric data, as well as to spectroscopic observations. It is based on multivariate correlation analysis techniques and, in its present implementation, is able to identify reverberating signals across the accretion disk and the broad line region (BLR) of active galactic nuclei (AGN). Statistical tests are defined to assess the significance of time-delay measurements using this approach, and the limitations of the adopted formalism are discussed. It is shown how additional constraints on some of the parameters of the problem may be incorporated into the analysis thereby leading to improved results. When applied to a sample of 14 Seyfert 1 galaxies having good-quality high-cadence photometric data, accretion disk scales and BLR sizes are simultaneously determined, on a case-by-case basis, in most objects. The BLR scales deduced here are in good agreement with the findings of independent spectrosc...

  9. Broad-scale spatial pattern of forest landscape types in the Guiana Shield

    Science.gov (United States)

    Gond, Valéry; Freycon, Vincent; Molino, Jean-François; Brunaux, Olivier; Ingrassia, Florent; Joubert, Pierre; Pekel, Jean-François; Prévost, Marie-Françoise; Thierron, Viviane; Trombe, Pierre-Julien; Sabatier, Daniel

    2011-06-01

    Detecting broad scale spatial patterns across the South American rainforest biome is still a major challenge. Although several countries do possess their own, more or less detailed land-cover map, these are based on classifications that appear largely discordant from a country to another. Up to now, continental scale remote sensing studies failed to fill this gap. They mostly result in crude representations of the rainforest biome as a single, uniform vegetation class, in contrast with open vegetations. A few studies identified broad scale spatial patterns, but only when they managed to map a particular forest characteristic such as biomass. The main objective of this study is to identify, characterize and map distinct forest landscape types within the evergreen lowland rainforest at the sub-continental scale of the Guiana Shield (north-east tropical South-America 10° North-2° South; 66° West-50° West). This study is based on the analysis of a 1-year daily data set (from January 1st to December 31st, 2000) from the VEGETATION sensor onboard the SPOT-4 satellite (1-km spatial resolution). We interpreted remotely sensed landscape classes (RSLC) from field and high resolution remote sensing data of 21 sites in French Guiana. We cross-analyzed remote sensing data, field observations and environmental data using multivariate analysis. We obtained 33 remotely sensed landscape classes (RSLC) among which five forest-RSLC representing 78% of the forested area. The latter were classified as different broad forest landscape types according to a gradient of canopy openness. Their mapping revealed a new and meaningful broad-scale spatial pattern of forest landscape types. At the scale of the Guiana Shield, we observed a spatial patterns similarity between climatic and forest landscape types. The two most open forest-RSLCs were observed mainly within the north-west to south-east dry belt. The three other forest-RSLCs were observed in wetter and less anthropized areas

  10. Series of broad resonances in atomic three-body systems

    CERN Document Server

    Diaz, D; Hu, C -Y

    2016-01-01

    We re-examine the series of resonances found earlier in atomic three-body systems by solving the Faddeev-Merkuriev integral equations. These resonances are rather broad and line-up at each threshold with gradually increasing gaps, the same way for all thresholds and irrespective of the spatial symmetry. We relate these resonances to the Gailitis mechanism, which is a consequence of the polarization potential.

  11. Broad Absorption Line Quasar catalogues with Supervised Neural Networks

    International Nuclear Information System (INIS)

    We have applied a Learning Vector Quantization (LVQ) algorithm to SDSS DR5 quasar spectra in order to create a large catalogue of broad absorption line quasars (BALQSOs). We first discuss the problems with BALQSO catalogues constructed using the conventional balnicity and/or absorption indices (BI and AI), and then describe the supervised LVQ network we have trained to recognise BALQSOs. The resulting BALQSO catalogue should be substantially more robust and complete than BI-or AI-based ones.

  12. Polarization properties of broad absorption line QSOs : new statistical clues

    OpenAIRE

    H. Lamy; Hutsemekers, Damien

    2004-01-01

    We report the results of several statistical tests performed on a large sample of 139 broad absorption line (BAL) QSOs with good quality optical spectra and/or optical polarization data. Correlations between ten optical indices and the polarization degree p[SUB]0[/SUB] are systematically searched for. We find six significant non-trivial correlations. In order to identify the most important correlations, we perform a principal component analysis with a sample of 30 BAL QSOs and eight quantitie...

  13. The broad spectrum revisited: Evidence from plant remains

    OpenAIRE

    Weiss, Ehud; Wetterstrom, Wilma; Nadel, Dani; Bar-Yosef, Ofer

    2004-01-01

    The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73–100] “broad spectrum revolution” (BSR) hypothesis, which posits that the...

  14. Flow structure in front of the broad-crested weir

    Directory of Open Access Journals (Sweden)

    Zachoval Zbyněk

    2015-01-01

    Full Text Available The paper deals with research focused on description of flow structure in front of broad-crested weir. Based on experimental measurement, the flow structure in front of the weir (the recirculation zone of flow and tornado vortices and flow structure on the weir crest has been described. The determined flow character has been simulated using numerical model and based on comparing results the suitable model of turbulence has been recommended.

  15. Using the occupational personality questionnaire (OPQ) for measuring broad traits

    OpenAIRE

    Deléne Visser; J. M. Du Toit

    2004-01-01

    The widespread acceptance of the Big Five model implies that personality consists of relatively independent dimensions that form a taxonomy whereby individual differences may be explained. The purpose of this study was to investigate whether the subscales of an established personality inventory that measures narrow traits of personality, the Occupational Personality Questionnaire (OPQ), could be reduced meaningfully to fit a broad factor model within a South African context. The OPQ 5.2 conce...

  16. Ecological restoration of southwestern ponderosa pine ecosystems: A broad perspective

    OpenAIRE

    Allen, C. D.; Savage, M.; Falk, D. A.; Suckling, K. F.; Swetnam, T.W.; Schulke, T.; Stacey, P. B.; Morgan, P.; Hoffman, M; Klingel, J. T.

    2002-01-01

    The purpose of this paper is to promote a broad and flexible perspective on ecological restoration of Southwestern (U.S.) ponderosa pine forests. Ponderosa pine forests in the region have been radically altered by Euro-American land uses, including livestock grazing, fire suppression, and logging. Dense thickets of young trees now abound, old-growth and biodiversity have declined, and human and ecological communities are increasingly vulnerable to destructive crown fires. A consensus has emer...

  17. Broad spectrum antiangiogenic treatment for ocular neovascular diseases.

    Directory of Open Access Journals (Sweden)

    Ofra Benny

    Full Text Available UNLABELLED: Pathological neovascularization is a hallmark of late stage neovascular (wet age-related macular degeneration (AMD and the leading cause of blindness in people over the age of 50 in the western world. The treatments focus on suppression of choroidal neovascularization (CNV, while current approved therapies are limited to inhibiting vascular endothelial growth factor (VEGF exclusively. However, this treatment does not address the underlying cause of AMD, and the loss of VEGF's neuroprotective can be a potential side effect. Therapy which targets the key processes in AMD, the pathological neovascularization, vessel leakage and inflammation could bring a major shift in the approach to disease treatment and prevention. In this study we have demonstrated the efficacy of such broad spectrum antiangiogenic therapy on mouse model of AMD. METHODS AND FINDINGS: Lodamin, a polymeric formulation of TNP-470, is a potent broad-spectrum antiangiogenic drug. Lodamin significantly reduced key processes involved in AMD progression as demonstrated in mice and rats. Its suppressive effects on angiogenesis, vascular leakage and inflammation were studied in a wide array of assays including; a Matrigel, delayed-type hypersensitivity (DTH, Miles assay, laser-induced CNV and corneal micropocket assay. Lodamin significantly suppressed the secretion of various pro-inflammatory cytokines in the CNV lesion including monocyte chemotactic protein-1 (MCP-1/Ccl2. Importantly, Lodamin was found to regress established CNV lesions, unlike soluble fms-like tyrosine kinase-1 (sFlk-1. The drug was found to be safe in mice and have little toxicity as demonstrated by electroretinography (ERG assessing retinal and by histology. CONCLUSIONS: Lodamin, a polymer formulation of TNP-470, was identified as a first in its class, broad-spectrum antiangiogenic drug that can be administered orally or locally to treat corneal and retinal neovascularization. Several unique properties

  18. Monetary Policy and the Credit Channel, Broad and Narrow

    OpenAIRE

    Torben W. Hendricks; Bernd Kempa

    2011-01-01

    Two variants of the credit channel of monetary policy transmission can be distinguished: a narrow bank lending channel, measured in terms of the supply of bank loans, and a broad credit channel focusing on the external finance premium in credit markets. In this paper, both variants of the credit channel are identified by applying Markov-switching models on US bank lending and interest rate data. We find the credit channel to be particularly potent during periods of financial distress, such as...

  19. Overview of the Illumina Sequencing Platform at the Broad Institute

    OpenAIRE

    Connolly, K.

    2011-01-01

    The constant increase in quality and quantity of Next-Generation sequencing data necessitates a parallel growth in sample preparation and a scalable tracking system. The Broad Institute's Illumina Sequencing Platform handles a variety of applications and comprises Illumina's latest hardware, software and kit releases, and a high-throughput sample preparation process. With our automated sample preparation and QC processes, we have been able to meet our increased capacity goals of up to 3,840 l...

  20. Hybrid grating reflector with high reflectivity and broad bandwidth

    DEFF Research Database (Denmark)

    Taghizadeh, Alireza; Park, Gyeong Cheol; Mørk, Jesper; Chung, Il-Sug

    2014-01-01

    We suggest a new type of grating reflector denoted hybrid grating (HG) which shows large reflectivity in a broad wavelength range and has a structure suitable for realizing a vertical cavity laser with ultra-small modal volume. The properties of the grating reflector are investigated numerically......). By using an active III-V layer, a laser can be realized where the gain region is integrated into the mirror itself...

  1. Does the light and broad $\\sigma$(500) exist?

    CERN Document Server

    Törnqvist, N A

    1999-01-01

    The lightest scalar and pseudoscalar nonets are discussed within the framework of the broken U3$\\times$U3 linear sigma model, and it is shown that already at the tree level this model works remarkably well predicting scalar masses and couplings not far from present experimental values, when all parameters are fixed from the pseudoscalar masses and decay constants. It is argued that this strongly suggests that the light and very broad $\\sigma$ resonance exists near 500 MeV.

  2. The Interplay of Biology and the Environment Broadly Defined

    OpenAIRE

    Diamond, Adele

    2009-01-01

    This special section of Developmental Psychology contains articles on the interplay of biology and the environment, broadly defined, that have the potential to change or challenge how developmental psychologists think. Topics include how experience affects gene expression; how genes affect how the environment is experienced and what effect the environment has; interactions between the environment and the presence or absence of early brain damage; motor neurons and the understanding of others’...

  3. High-throughput discovery of broad-spectrum peptide antibiotics

    OpenAIRE

    Rathinakumar, Ramesh; Wimley, William C.

    2010-01-01

    Membrane-permeabilizing peptide antibiotics are an underutilized weapon in the battle against drug-resistant microorganisms. This is true, in part, because of the bottleneck caused by the lack of explicit design principles and the paucity of simple high-throughput methods for selection. In this work, we characterize the requirements for broad-spectrum antimicrobial activity by membrane permeabilization and find that different microbial membranes have very different susceptibilities to permeab...

  4. Mapping plant functional types over broad mountainous regions

    OpenAIRE

    Danlu Cai; Yanning Guan; Shan Guo; Chunyan Zhang; Klaus Fraedrich

    2014-01-01

    Research on global climate change requires plant functional type (PFT) products. Although several PFT mapping procedures for remote sensing imagery are being used, none of them appears to be specifically designed to map and evaluate PFTs over broad mountainous areas which are highly relevant regions to identify and analyze the response of natural ecosystems. We present a methodology for generating soft classifications of PFTs from remotely sensed time series that are based on a hierarchical s...

  5. Biodiversity inhibits parasites: Broad evidence for the dilution effect

    OpenAIRE

    Civitello, David J.; Cohen, Jeremy; Fatima, Hiba; Halstead, Neal T.; Liriano, Josue; McMahon, Taegan A.; Ortega, C. Nicole; Sauer, Erin Louise; Sehgal, Tanya; Young, Suzanne; Rohr, Jason R.

    2015-01-01

    The dilution effect hypothesis suggests that diverse ecological communities limit disease spread via several mechanisms. Therefore, biodiversity losses could worsen epidemics that harm humans and wildlife. However, there is contentious debate over whether the hypothesis applies broadly, especially for parasites that infect humans. We address this fundamental question with a formal meta-analysis of >200 assessments relating biodiversity to disease in >60 host–parasite systems. We find overwhel...

  6. Oxygen consumption of rats with broad intestinal resection

    OpenAIRE

    Luz J.; Griggio M.A.; Fagundes D.J.; Araújo R.M.; Marcondes W.

    2000-01-01

    The study was performed to investigate possible alterations in oxygen consumption in an animal model with broad intestinal resection. Oxygen consumption and the thermal effect of a short meal were measured in rats subjected to short bowel syndrome. Four groups of rats were used. Group I was the control group, group II was sham operated, group III was submitted to 80% jejunum-ileum resection, and group IV was submitted to 80% jejunum-ileum resection with colon interposition. Ninety days after ...

  7. Shareholder, stakeholder-owner or broad stakeholder maximization

    DEFF Research Database (Denmark)

    Mygind, Niels

    2004-01-01

    including the shareholders of a company. Although it may be the ultimate goal for Corporate Social Responsibility to achieve this kind of maximization, broad stakeholder maximization is quite difficult to give a precise definition. There is no one-dimensional measure to add different stakeholder benefits...... defined by other stakeholders' interests. These constraints vary for dif-ferent stakeholder owners and new standards for Corporate Social Responsibility and more active political consumers will strengthen these constraints....

  8. On the geometry of broad emission region in quasars

    CERN Document Server

    Decarli, R; Treves, A; Falomo, R

    2008-01-01

    We study the geometry of the Hbeta broad emission region by comparing the M_BH values derived from Hbeta through the virial relation with those obtained from the host galaxy luminosity in a sample of 36 low redshift (z around 0.3) quasars. This comparison lets us infer the geometrical factor f needed to de-project the line-of-sight velocity component of the emitting gas. The wide range of f values we found, together with the strong dependence of f on the observed line width, suggests that a disc-like model for the broad line region is preferable to an isotropic model, both for radio loud and radio quiet quasars. We examined similar observations of the CIV line and found no correlation in the width of the two lines. Our results indicate that an inflated disc broad line region, in which the Carbon line is emitted in a flat disc while Hbeta is produced in a geometrically thick region, can account for the observed differences in the width and shape of the two emission lines.

  9. Identification of the Broad Solar Emission Features Near 117 nm

    CERN Document Server

    Avrett, E H; Loeser, R; Avrett, Eugene H.; Kurucz, Robert L.; Loeser, Rudolf

    2006-01-01

    Wilhelm et al. have recently called attention to the unidentified broad emission features near 117 nm in the solar spectrum. They discuss the observed properties of these features in detail but do not identify the source of this emission. We show that the broad autoionizing transitions of neutral sulfur are responsible for these emission features. Autoionizing lines of \\ion{S}{i} occur throughout the spectrum between Lyman alpha and the Lyman limit. Sulfur is a normal contributor to stellar spectra. We use non-LTE chromospheric model calculations with line data from the Kurucz 2004 \\ion{S}{i} line list to simulate the solar spectrum in the range 116 to 118 nm. We compare the results with SUMER disk-center observations from Curdt et al. and limb observations from Wilhelm et al. Our calculations generally agree with the SUMER observations of the broad autoionizing \\ion{S}{i} emission features, the narrow \\ion{S}{i} emission lines, and the continuum in this wavelength region, and agree with basic characteristics...

  10. Broad-line Balmer Decrements in Blue Active Galactic Nuclei

    CERN Document Server

    Dong, Xiaobo; Wang, Jianguo; Yuan, Weimin; Zhou, Hongyan; Dai, Haifeng; Zhang, Kai

    2007-01-01

    We have investigated the broad-line Balmer decrements (Halpha/Hbeta) for a large, homogeneous sample of Seyfert 1 galaxies and QSOs using spectroscopic data obtained in the Sloan Digital Sky Survey. The sample, drawn from the Fourth Data Release, comprises 446 low redshift (z < 0.35) active galactic nuclei (AGN) that have blue optical continua as indicated by the spectral slopes in order to minimize the effect of dust extinction. We find that (i) the distribution of the intrinsic broad-line Halpha/Hbeta ratio can be well described by log-Gaussian, with a peak at Halpha/Hbeta=3.06 and a standard deviation of about 0.03 dex only; (ii) the Balmer decrement does not correlate with AGN properties such as luminosity, accretion rate, and continuum slope, etc.; (iii) on average, the Balmer decrements are found to be only slightly larger in radio-loud sources (3.37) and sources having double-peaked emission-line profiles (3.27) compared to the rest of the sample. We therefore suggest that the broad-line Halpha/Hbet...

  11. Building for energy conservation

    Energy Technology Data Exchange (ETDEWEB)

    Burberry, P.

    1978-01-01

    Ways in which buildings may be designed to increase thermal efficiency are discussed, giving first of all examples of thermal design in relation to climate. How the building itself may be designed to take advantage of solar energy and the ways in which heat loss takes place are described; the effect of design variables such as siting, volume, and insulation is shown. The book also reviews the development of thermal regulations for health and comfort and, more recently, energy conservation. It discusses the possitilities and difficulties of legislation for energy saving. The UK regulations are given in detail together with descriptions of the FHA and ASHRAE recommendations for the USA and the lastest Scandinavian norms. The author argues that no significant cost need be involved in many of the aspects of thermal design, e.g., shape and fenestration; and that these factors should automatically be taken into account by designers. Even existing buildings can be adapted in various respects to save energy consumption. The book concludes with an explanation of calculation methods for U-values, heat loss, plant sizing, seasonal heat requirements, and other procedures, amply illustrated with tables and graphs.

  12. A checklist for ecological management of landscapes for conservation.

    Science.gov (United States)

    Lindenmayer, David; Hobbs, Richard J; Montague-Drake, Rebecca; Alexandra, Jason; Bennett, Andrew; Burgman, Mark; Cale, Peter; Calhoun, Aram; Cramer, Viki; Cullen, Peter; Driscoll, Don; Fahrig, Lenore; Fischer, Joern; Franklin, Jerry; Haila, Yrjo; Hunter, Malcolm; Gibbons, Philip; Lake, Sam; Luck, Gary; MacGregor, Chris; McIntyre, Sue; Nally, Ralph Mac; Manning, Adrian; Miller, James; Mooney, Hal; Noss, Reed; Possingham, Hugh; Saunders, Denis; Schmiegelow, Fiona; Scott, Michael; Simberloff, Dan; Sisk, Tom; Tabor, Gary; Walker, Brian; Wiens, John; Woinarski, John; Zavaleta, Erika

    2008-01-01

    The management of landscapes for biological conservation and ecologically sustainable natural resource use are crucial global issues. Research for over two decades has resulted in a large literature, yet there is little consensus on the applicability or even the existence of general principles or broad considerations that could guide landscape conservation. We assess six major themes in the ecology and conservation of landscapes. We identify 13 important issues that need to be considered in developing approaches to landscape conservation. They include recognizing the importance of landscape mosaics (including the integration of terrestrial and aquatic areas), recognizing interactions between vegetation cover and vegetation configuration, using an appropriate landscape conceptual model, maintaining the capacity to recover from disturbance and managing landscapes in an adaptive framework. These considerations are influenced by landscape context, species assemblages and management goals and do not translate directly into on-the-ground management guidelines but they should be recognized by researchers and resource managers when developing guidelines for specific cases. Two crucial overarching issues are: (i) a clearly articulated vision for landscape conservation and (ii) quantifiable objectives that offer unambiguous signposts for measuring progress. PMID:17927771

  13. Relativistic dynamics without conservation laws

    OpenAIRE

    Rothenstein, Bernhard; Popescu, Stefan

    2006-01-01

    We show that relativistic dynamics can be approached without using conservation laws (conservation of momentum, of energy and of the centre of mass). Our approach avoids collisions that are not easy to teach without mnemonic aids. The derivations are based on the principle of relativity and on its direct consequence, the addition law of relativistic velocities.

  14. African Conservation Tillage Network Website

    OpenAIRE

    African Conservation Tillage Network (ACT)

    2009-01-01

    Metadata only record Maintained by the African Conservation Tillage Network (ACT), this website provides information on Conservation Agriculture in an African context and gathered by stakeholders (NGOs) native to the continent. Resources on projects, practices, reports, and training courses are provided.

  15. Orchid conservation: making the links.

    Science.gov (United States)

    Fay, Michael F; Pailler, Thierry; Dixon, Kingsley W

    2015-09-01

    Orchidaceae, one of the largest families of flowering plants, present particular challenges for conservation, due in great part to their often complex interactions with mycorrhizal fungi, pollinators and host trees. In this Highlight, we present seven papers focusing on orchids and their interactions and other factors relating to their conservation. PMID:26311710

  16. Concluding Remarks on River Conservation

    OpenAIRE

    Elosegi, Arturo; Sabater, Sergi; Boulton, Andrew

    2013-01-01

    We have pragmatic and ethical obligations to conserve rivers and their biodiversity. This chapter outlines how and why river conservation is important. To make a difference, we must act as individuals and groups, using water wisely and protecting vulnerable assets such as water quality, riparian zones and aquatic biodiversity

  17. Comparative Analysis of Two Broad-Range PCR Assays for Pathogen Detection in Positive-Blood-Culture Bottles: PCR–High-Resolution Melting Analysis versus PCR-Mass Spectrometry

    OpenAIRE

    Jeng, Kevin; Gaydos, Charlotte A; Blyn, Lawrence B.; Yang, Samuel; Won, Helen; Matthews, Heather; Toleno, Donna; Hsieh, Yu-Hsiang; Carroll, Karen C.; Hardick, Justin; Masek, Billy; Kecojevic, Alexander; Sampath, Rangarajan; Peterson, Stephen; Rothman, Richard E.

    2012-01-01

    Detection of pathogens in bloodstream infections is important for directing antimicrobial treatment, but current culture-based approaches can be problematic. Broad-range PCR assays which target conserved genomic motifs for postamplification amplicon analysis permit detection of sepsis-causing pathogens. Comparison of different broad-range assays is important for informing future implementation strategies. In this study, we compared positive-blood-culture bottles processed by PCR coupled to hi...

  18. Conservation business: sustaining Africa's future

    Directory of Open Access Journals (Sweden)

    I.P. Sonnekus

    2001-07-01

    Full Text Available Protected areas in Africa are threatened by a lack of funds to conduct their work effectively and by extremely poor communities that surround their resource-rich areas. We believe that conservation staff suffer from mental blocks. They assume that business and profitability reflect unethical processes that destroy natural resources. We developed a workshop process that allows conservationists to integrate entrepreneurial thinking with conservation principles and ethics. We measured perceptions both before and after such a workshop to assess the impact of the process. The process assisted conservationists at the Southern African Wildlife College to develop the integrated mental frameworks that are required to develop conservation into a sustainable business. The group internalised the new mental framework, whereby conservation and business, when integrated in an ethical manner, are viewed as virtually synonymous. The group also identified many innovative ways in which they could derive sustainable income from their natural resources while simultaneously achieving their conservation objectives.

  19. Is international conservation aid enough?

    Science.gov (United States)

    Law, Elizabeth A.

    2016-02-01

    Bare et al (2015 Environ. Res. Lett. 10 125010) ask an important question: is international conservation enough? Since the 1990’s international conservation donors have spent over 3.4 billion on biodiversity conservation related projects in sub-Saharan Africa. Both donors and recipients have a right to know if this is effective. Surprisingly, this question is rarely asked. It is a difficult question—involving many rival social, environmental, and economic explanations. Bare, Kauffman and Miller uncover some interesting associations, supporting existing hypotheses and proposing their own: that conservation aid alone is insufficient to mitigate drivers of deforestation (and in some cases may even exacerbate forest loss). This controversial result warrants further investigation—but what is needed now is nuance and robustness in further analyses, to have more confidence in the critique and it’s implications for international conservation aid.

  20. Optimal Conservation of Migratory Species

    Science.gov (United States)

    Martin, Tara G.; Chadès, Iadine; Arcese, Peter; Marra, Peter P.; Possingham, Hugh P.; Norris, D. Ryan

    2007-01-01

    Background Migratory animals comprise a significant portion of biodiversity worldwide with annual investment for their conservation exceeding several billion dollars. Designing effective conservation plans presents enormous challenges. Migratory species are influenced by multiple events across land and sea–regions that are often separated by thousands of kilometres and span international borders. To date, conservation strategies for migratory species fail to take into account how migratory animals are spatially connected between different periods of the annual cycle (i.e. migratory connectivity) bringing into question the utility and efficiency of current conservation efforts. Methodology/Principal Findings Here, we report the first framework for determining an optimal conservation strategy for a migratory species. Employing a decision theoretic approach using dynamic optimization, we address the problem of how to allocate resources for habitat conservation for a Neotropical-Nearctic migratory bird, the American redstart Setophaga ruticilla, whose winter habitat is under threat. Our first conservation strategy used the acquisition of winter habitat based on land cost, relative bird density, and the rate of habitat loss to maximize the abundance of birds on the wintering grounds. Our second strategy maximized bird abundance across the entire range of the species by adding the constraint of maintaining a minimum percentage of birds within each breeding region in North America using information on migratory connectivity as estimated from stable-hydrogen isotopes in feathers. We show that failure to take into account migratory connectivity may doom some regional populations to extinction, whereas including information on migratory connectivity results in the protection of the species across its entire range. Conclusions/Significance We demonstrate that conservation strategies for migratory animals depend critically upon two factors: knowledge of migratory

  1. Stable isotope ratios reveal food source of benthic fish and crustaceans along a gradient of trophic status in the East China Sea

    Science.gov (United States)

    Chang, Ni-Na; Shiao, Jen-Chieh; Gong, Gwo-Ching; Kao, Shuh-Ji; Hsieh, Chih-hao

    2014-08-01

    The East China Sea (ECS) receives large quantities of particulate organic matter (POM) and inorganic nutrients transported from the Changjiang (Yangtze River), which have produced high productivity in the northwestern ECS. This study evaluated potential contributions of terrigenous POM (allochthonous food source) and nutrient-induced marine production (autochthonous source) to the ECS benthic ecosystem by analyzing stable isotopic compositions of phytoplankton, zooplankton, benthic crustaceans and fish. Benthic consumers exhibited δ13C values similar to those of their autochthonous food sources (i.e., phytoplankton and zooplankton), revealing their major reliance on marine production. In contrast, the δ13C values of benthic fish (-19.6‰ to -13.5‰) and crustaceans (-18.9‰ to -15.0‰) were much higher than that of terrigenous POM (-25.7‰), which generally accounted for less than 20% of the most fish diet. Phytoplankton and zooplankton generally exhibited higher δ13C values at eutrophic and highly productive inshore sites than at oligotrophic offshore sites. This enrichment of inshore δ13C values was mainly attributed to lower photosynthetic fractionation during algal blooms, an effect that was further enhanced during flood period of the Changjiang. The δ13C values of demersal fish assemblages were also significantly higher at inshore sites and decreased seaward. However, fish δ15N values and their estimated trophic levels showed relatively small spatial variation. The disproportionate variations in δ13C and δ15N values suggested that the enriched C isotopic signatures derived from an elevated δ13C baseline of the inshore food web instead of trophic enrichment of the isotopic ratios. The significantly positive correlations between concentrations of chlorophyll a and nutrients versus fish δ13C provided further evidence for the use of pelagic algal bloom materials by inshore consumers. The isotopic and oceanographic survey data suggested that

  2. Distribución y abundancia de crustáceos en humedales de Tabasco, México Abundance and distribution of crustaceans in wetlands of Tabasco

    Directory of Open Access Journals (Sweden)

    Everardo Barba

    2010-10-01

    Full Text Available El estado de Tabasco presenta una compleja y alta diversidad de humedales que incluye tipos palustres (20.72%, costeros (3.93%, lacustres (1.74% y ribereños (1.37%, los cuales cubren el 27% del territorio estatal. La diversidad faunística en estos ambientes comprende invertebrados y vertebrados, donde la mayor parte de los registros son de especies de interés comercial. Se presenta el inventario de crustáceos recolectados desde 2003 hasta la fecha en las subregiones Sierra, Ríos y Pantanos. La recolección fue diurna, en 14 localidades (ambientes lóticos y lénticos, mediante nucleador y draga para la infauna, y arrastres con diferentes artes para la epifauna. Se obtuvieron 2 370 organismos que pertenecen a 4 órdenes, 15 familias, 17 géneros y 17 especies. Las especies más abundantes fueron Discapseudes holthuisi Bacescu y Gutu, 1975 (62%, Macrobrachium acanthurus (Wiegmann, 1836 (12%, Leptochirus sp. Zaddach, 1844 (8% y Palaemonetes vulgaris (Say, 1818 (7%, sumando el 89% del total. El 67% de la abundancia correspondió a la infauna y el 33% a la epifauna. El 81% de los crustáceos se capturaron en sistemas lénticos y el resto en sistemas lóticos. Este trabajo contribuye con nuevos registros de crustáceos en humedales de Tabasco.The state of Tabasco is characterised by complex and diverse wetlands of different types: palustrine (20.72%, coastal (3.93%, lacustrine (1.74% and riverine (1.37%, covering 27% of its surface. Faunal diversity of these wetlands includes invertebrates and vertebrates, most of the available records come from species with commercial importance. The list of crustaceans collected from 2003 to date in the subregions Sierra, Ríos and Pantanos, is presented. The sampling at 14 localities was diurnal (lotic and lentic environments, using cores and dredges for the infauna and different nets for epifauna. A total of 2 370 organisms belonging to 4 orders, 15 families, 17 genera and 17 species, was obtained. The most

  3. Comparison of bioassays using the anostracan crustaceans Artemia salina and Thamnocephalus platyurus for plant extract toxicity screening Comparação de bioensaios com os crustáceos Artemia salina e Thamnocephalus platyurus para abordagem de extratos de plantas com toxicidade

    OpenAIRE

    Pablo Mayorga; Karen R. Pérez; Sully M. Cruz; Armando Cáceres

    2010-01-01

    Three lethality bioassays, using the salt-water crustacean Artemia salina Leach, Artemiidae, (conventional 96 microwell plate test and the Artoxkit M microbiotest) and the freshwater crustacean Thamnocephalus platyurus Packard, Thamnocephalidae, (Thamnotoxkit F microbiotest), were compared using extracts of ten Guatemalan plant species. It was previously observed that five of them have anti-Artemia activity. These were: Solanum americanum Mill., Solanaceae, Gliricidia sepium (Jacq.) Kunth ex ...

  4. Broad Iron Lines in AGN and X-ray Binaries

    OpenAIRE

    Fabian, A.C.

    2004-01-01

    Several AGN and black hole X-ray binaries show a clear very broad iron line which is strong evidence that the black holes are rapidly spinning. Detailed analysis of these objects shows that the emission line is not significantly affected by absorption and that the source variability is principally due to variation in amplitude of a power-law. Underlying this is a much less variable, relativistically-smeared, reflection-dominated, component which carries the imprint of strong gravity at a few ...

  5. Spectropolarimetry of Radio-Selected Broad Absorption Line Quasars

    OpenAIRE

    DiPompeo, M. A.; Brotherton, M. S.; Becker, R. H.; Tran, H. D.; Gregg, M. D.; White, R L; Laurent-Muehleisen, S. A.

    2010-01-01

    We report spectropolarimetry of 30 radio-selected broad absorption line (BAL) quasars with the Keck Observatory, 25 from the sample of Becker et al. (2000). Both high and low-ionization BAL quasars are represented, with redshifts ranging from 0.5 to 2.5. The spectropolarimetric properties of radio-selected BAL quasars are very similar to those of radio-quiet BAL quasars: a sizeable fraction (20%) show large continuum polarization (2-10%) usually rising toward short wavelengths, emission lines...

  6. Polar Outflows in Six Broad Absorption Line Quasars

    OpenAIRE

    Zhou, Hongyan; Wang, Tinggui; Wang, Huiyuan; Wang, Junxian; Yuan, Weimin; Lu, Yu

    2005-01-01

    Using the radio observations by FIRST and NVSS, we build a sample of 151 radio variable quasars selected from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3). Six (probably another two) among them are classified as broad absorption line (BAL) quasars, with radio flux variations of a few 10 percent within 1.5-5 years. Such large amplitudes of the variations imply brightness temperatures much higher than the inverse Compton limits (10$^{12}$ K) in all the BAL quasars, suggesting the pres...

  7. New focal plane detector system for the broad range spectrometer

    International Nuclear Information System (INIS)

    A focal plane detector system consisting of a vertical drift chamber, parallel plate avalanche counters, and an ionization chamber with segmented anodes has been installed in the Broad Range Spectrometer at the Holifield Facility at Oak Ridge. The system, which has been designed for use with light-heavy ions with energies ranging from 10 to 25 MeV/amu, has a position resolution of approx. 0.1 mm, a scattering angle resolution of approx. 3 mrad, and a mass resolution of approx. 1/60

  8. Broadly tunable quasi-phase-matching in nonlinear metamaterials

    International Nuclear Information System (INIS)

    The ability to tune the quasi-phase-matching (QPM) frequency is a highly desirable though lacking feature of many nonlinear devices. To this end, we consider QPM in a special class of active nonlinear metamaterials (MMs), whose properties can be controlled postfabrication. By application of a tunable, periodic perturbation in the linear susceptibility (magnetic or electric) of a MM, a single nonlinear device can be constructed to operate over an exceedingly broad bandwidth. We propose a nonlinear MM for QPM second-order harmonic generation at terahertz frequencies, predicted to have a tunable bandwidth of over 100%.

  9. Broad spectrum assessment of the epitope fluctuation--Immunogenicity hypothesis.

    Science.gov (United States)

    Grosch, Jason S; Yang, Jing; Shen, Alice; Sereda, Yuriy V; Ortoleva, Peter J

    2015-11-01

    Prediction of immunogenicity is a substantial barrier in vaccine design. Here, a molecular dynamics approach to assessing the immunogenicity of nanoparticles based on structure is presented. Molecular properties of epitopes on nonenveloped viral particles are quantified via a set of metrics. One such metric, epitope fluctuation (and implied flexibility), is shown to be inversely correlated with immunogenicity for each of a broad spectrum of nonenveloped viruses. The molecular metrics and experimentally determined immunogenicities for these viruses are archived in the open-source vaccine computer-aided design database. Results indicate the promise of computer-aided vaccine design to bring greater efficiency to traditional lab-based vaccine discovery approaches. PMID:26187254

  10. Earthquake response considerations of broad liquid storage tanks

    Science.gov (United States)

    Cambra, F. J.

    1982-11-01

    The influences of tank geometry and foundation stiffness variation on the simulated seismic structural response of a model broad tank are discussed. An empirical method for describing tank bottom plate uplift geometry is proposed which recognizes radial catenary force and foundation stiffness. Axial symmetric lift, static tilt and dynamic shaking table tests were performed in the University of California, Berkeley, earthquake simulator laboratory. A structural geometric survey of a 63 ft - 10 inches tall by 289 ft - 6 inches diameter crude oil storage tank was conducted to establish a comparative base by which to evaluate the model tank eccentricities.

  11. Antiviral drug discovery: broad-spectrum drugs from nature.

    OpenAIRE

    Martinez, J P; Sasse, F; Brönstrup, M; Diez, J; Meyerhans, A

    2015-01-01

    Covering: up to April 2014. The development of drugs with broad-spectrum antiviral activities is a long pursued goal in drug discovery. It has been shown that blocking co-opted host-factors abrogates the replication of many viruses, yet the development of such host-targeting drugs has been met with scepticism mainly due to toxicity issues and poor translation to in vivo models. With the advent of new and more powerful screening assays and prediction tools, the idea of a drug that can efficien...

  12. Report on broad reconsiderations. Part 1. Energy and Climate

    International Nuclear Information System (INIS)

    In twenty policy areas various working groups have studied variants that can lead to a 20% budget cut in the government budgets of the Netherlands, which must be realized in 2015. The aim of the reconsiderations is to use less government means to realize the same results, or even better results if possible. The broad reconsideration in the field of energy and climate focuses on the expenditure for renewable energy and energy efficiency, mitigating (inter)national climate policy and fiscal benefits. This report addresses six policy variants.

  13. The role of participant learning in community conservation in the Arabuko-Sokoke Forest, Kenya

    Directory of Open Access Journals (Sweden)

    A John Sinclair

    2011-01-01

    Full Text Available While the community conservation approach has gained broad acceptance, questions regarding its effectiveness persist. Many of the changes that community conservation projects seek to impart among participants correspond with their values and attitudes. This paper proposes the use of transformative learning as one of the measures of the success of a community conservation project in terms of promoting learning that leads to significant changes in a participant′s values and attitudes. Using the ASSETS programme in coastal Kenya as a case study, we focused on participant learning and the extent to which such learning resulted in a more positive attitude towards conservation of the Arabuko-Sokoke Forest. Participation in ASSETS resulted in instrumental learning and communicative learning, as described in the transformative learning theory. Findings show that participation in ASSETS led to a variety of learning outcomes, such as learning new information about the forest, and learning to question local cultural norms and speak out for conservation.

  14. Conserving one earth -a look at world conservation

    Directory of Open Access Journals (Sweden)

    F. Vollmar

    1977-01-01

    Full Text Available It is a great pleasure to join in this symposium held on the occasion of the 50th Anniversary of the National Parks Board of South Africa. I am deeply honoured to have been entrusted with presenting the Keynote Address to the symposium, which brings together those responsible for conservation in southern Africa, and I come here representing both the World Wildlife Fund and its sister organisation IUCN, the Interna- tional Union for Conservation of Nature and Natural Resources. Having considered contents of the programme before us, I have felt it appropriate to talk on the subject of "Conserving One Earth". First I wish to look at our Earth as we find it today and then discuss the role of conservation both as a tool for wise development and in ensuring that wild things and wild places can continue to contribute to our quality of life.

  15. Conservation Lands and Preserves, Private - Volusia County Conservation Corridor

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Volusia Conservation Corridor (VCC) is a mosaic of contiguous parcels of land, approximately 55,000 acres in size, which sits essentially in the middle of the...

  16. A patient presenting with a perivascular epithelioid cell tumor in the broad ligament: a case report

    Directory of Open Access Journals (Sweden)

    Ross Claire

    2011-08-01

    Full Text Available Abstract Introduction Perivascular epithelioid cell tumors are a family of rare mesenchymal tumors composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. They can originate in any visceral organ or soft tissue and include a range of lesions such as angiomyolipoma, clear cell 'sugar' tumor of the lung, lymphangioleiomyomatosis and clear cell myomelanocytic tumors of the falciparum ligament/ligament teres. Due to their rarity and varied sites and presentation, management of these tumors remains highly challenging. Case Presentation A 46-year-old para 2 Caucasian woman initially presented to the general surgeons at our hospital in North West London with abdominal pain. Laparoscopy revealed a right broad ligament hematoma, which was thought to be iatrogenic in origin, from insertion of the Veress needle at the time of surgery, and was managed conservatively. Upon her re-presentation two months later with severe pain, ultrasound scanning revealed the hematoma had increased in size and she underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histology results from necrotic tissue from the hematoma led to a diagnosis of perivascular epithelioid cell tumor. She was then referred to a tertiary oncology center, where she underwent several further operations in an attempt to debulk the tumor for symptomatic relief of her pain, with limited success. She is now taking the immunosuppressive drug sirolimus, which has produced a modest reduction in tumor size. She is now 47 months on from initial presentation. Conclusions A literature search has revealed only six other case reports of broad ligament perivascular epithelioid cell tumors, with varied presentations and management. The longest duration of follow-up was 21 months. Only five other cases of perivascular epithelioid cell tumor managed with sirolimus have been reported. We therefore feel that this report highlights some of the

  17. An evolutionary analysis of flightin reveals a conserved motif unique and widespread in Pancrustacea.

    Science.gov (United States)

    Soto-Adames, Felipe N; Alvarez-Ortiz, Pedro; Vigoreaux, Jim O

    2014-01-01

    Flightin is a thick filament protein that in Drosophila melanogaster is uniquely expressed in the asynchronous, indirect flight muscles (IFM). Flightin is required for the structure and function of the IFM and is indispensable for flight in Drosophila. Given the importance of flight acquisition in the evolutionary history of insects, here we study the phylogeny and distribution of flightin. Flightin was identified in 69 species of hexapods in classes Collembola (springtails), Protura, Diplura, and insect orders Thysanura (silverfish), Dictyoptera (roaches), Orthoptera (grasshoppers), Pthiraptera (lice), Hemiptera (true bugs), Coleoptera (beetles), Neuroptera (green lacewing), Hymenoptera (bees, ants, and wasps), Lepidoptera (moths), and Diptera (flies and mosquitoes). Flightin was also found in 14 species of crustaceans in orders Anostraca (water flea), Cladocera (brine shrimp), Isopoda (pill bugs), Amphipoda (scuds, sideswimmers), and Decapoda (lobsters, crabs, and shrimps). Flightin was not identified in representatives of chelicerates, myriapods, or any species outside Pancrustacea (Tetraconata, sensu Dohle). Alignment of amino acid sequences revealed a conserved region of 52 amino acids, referred herein as WYR, that is bound by strictly conserved tryptophan (W) and arginine (R) and an intervening sequence with a high content of tyrosines (Y). This motif has no homologs in GenBank or PROSITE and is unique to flightin and paraflightin, a putative flightin paralog identified in decapods. A third motif of unclear affinities to pancrustacean WYR was observed in chelicerates. Phylogenetic analysis of amino acid sequences of the conserved motif suggests that paraflightin originated before the divergence of amphipods, isopods, and decapods. We conclude that flightin originated de novo in the ancestor of Pancrustacea > 500 MYA, well before the divergence of insects (~400 MYA) and the origin of flight (~325 MYA), and that its IFM-specific function in Drosophila is a more

  18. Do private conservation activities match science-based conservation priorities?

    Directory of Open Access Journals (Sweden)

    Jonathan R B Fisher

    Full Text Available BACKGROUND: Private land conservation is an essential strategy for biodiversity protection in the USA, where half of the federally listed species have at least 80% of their habitat on private lands. We investigated the alignment between private land protection conducted by the world's largest land trust (The Nature Conservancy and the science driven identification of priority areas for conservation. This represents the first quantitative assessment of the influence of defining priority areas on the land acquisitions of a conservation non-governmental organization (NGO. METHODOLOGY/PRINCIPAL FINDINGS: The lands acquired by The Nature Conservancy (TNC were analyzed using GIS to determine to what extent they were in areas defined as priorities for conservation. The spatial analysis of TNC lands was broken up into land known to be acquired in the last five years, five to ten years ago, prior to ten years ago, and anytime during the last sixty years (including previous sets of data plus acquisitions lacking a date. For the entire history of TNC the proportion of TNC lands within the priority areas was 74%. Prior to 10 years ago it was 80%, 5-10 years ago it was 76%, and in the last five years it was 81%. Conservation easements were found to have lower alignment with priority areas (64% than outright fee simple acquisitions (86%. CONCLUSIONS/SIGNIFICANCE: Overall the location of lands acquired was found to be well aligned with the priority areas. Since there was comparable alignment in lands acquired before and after formalized conservation planning had been implemented as a standard operating procedure, this analysis did not find evidence that defining priority areas has influenced land acquisition decisions.

  19. The conservation of orbital symmetry

    CERN Document Server

    Woodward, R B

    2013-01-01

    The Conservation of Orbital Symmetry examines the principle of conservation of orbital symmetry and its use. The central content of the principle was that reactions occur readily when there is congruence between orbital symmetry characteristics of reactants and products, and only with difficulty when that congruence does not obtain-or to put it more succinctly, orbital symmetry is conserved in concerted reaction. This principle is expected to endure, whatever the language in which it may be couched, or whatever greater precision may be developed in its application and extension. The book ope

  20. Climate, Carbon, Conservation and Communities

    Energy Technology Data Exchange (ETDEWEB)

    Vaugn, Kit; Brickell, Emily [WWF-UK (United Kingdom); Roe, Dilys; Reid, Hannah; Elliot, Jo

    2007-07-01

    The growing market for carbon offers great opportunities for linking greenhouse gas mitigation with conservation of forests and biodiversity, and the generation of local livelihoods. For these combined objectives to be achieved, strong governance is needed along with institutions that ensure poor people win, rather than lose out, from the new challenges posed by climate change. This briefing paper explores the opportunities from and limitations to carbon-based funds for conservation and development. It highlights mechanisms that may help secure benefits for climate, conservation and communities.

  1. Value basis for conservation policy

    Energy Technology Data Exchange (ETDEWEB)

    Leiss, W.

    1981-01-01

    This paper is a case study in attempting to apply a particular value (caring) to the domain of social policy, specifically resource conservation policy. The argument is that our consumer society erodes the social basis for the development by individuals of a sense of well-being and personal identity, and that a conservation ethic based on the concept of caring could provide a foundation in practical morality and public policy for a viable sense of well-being. Conservation, then, goes beyond eliminating wasteful consumption to encompass a public commitment that can further economic and social goals. 11 references.

  2. Local Responses to Participatory Conservation in Annapurna Conservation Area, Nepal

    Science.gov (United States)

    Khadka, Damodar; Nepal, Sanjay K.

    2010-02-01

    Biodiversity conservation has undergone a profound change in philosophy, policies and management approaches over the last forty years. The traditional top-down approach to nature protection has been widely criticized for failing to include critical social elements in management practices, and is being gradually replaced by a slew of participatory strategies under the rubric of bottom-up conservation. The new approach recognizes local communities as key partners in wildlife management and seeks their participation in social development and biodiversity conservation. However, every social context is different in its structure and functions, and in the way social groups respond to calls for participation. In order to gain a better understanding of the approach and the barriers encountered in its implementation, a questionnaire survey of 188 households was employed in the communities of the Upper Mustang extension of Annapurna Conservation Area (ACA) in Nepal. The study provides a comparative analysis of community participation and its barriers between Non-Tourist (NT) and Tourist (TV) villages. The results revealed important differences between the two groups in terms of their participation in community programs, barriers to participation, and perception of benefits from participation. Owing to their distinct spatial, demographic and attitudinal differences, the two village groups have their own sets of needs, values and motivation factors which cannot be generalized and treated as such. The research clearly identifies the need for the conservation agency to be creative in devising strategies and initiatives appropriate to specific social groups so as to optimize their input in participatory conservation.

  3. Discrimination of ionic species from broad-beam ion sources

    International Nuclear Information System (INIS)

    The performance of a broad-beam, three-grid, ion extraction system incorporating radio frequency (RF) mass discrimination was investigated experimentally. This testing demonstrated that the system, based on a modified single-stage Bennett mass spectrometer, can discriminate between ionic species having about a 2-to-1 mass ratio while producing a broad-beam of ions with low kinetic energy (less than 15 eV). Testing was conducted using either argon and krypton ions or atomic and diatomic oxygen ions. A simple one-dimensional model, which ignores magnetic field and space-charge effects, was developed to predict the species separation capabilities as well as the kinetic energies of the extracted ions. The experimental results correlated well with the model predictions. This RF mass discrimination system can be used in applications where both atomic and diatomic ions are produced, but a beam of only one of the species is desired. An example of such an application is a 5 eV atomic oxygen source. This source would produce a beam of atomic oxygen with 5 eV kinetic energy, which would be directed onto a material specimen, to simulate the interaction between the surface of a satellite and the rarefied atmosphere encountered in low-Earth orbit

  4. Peculiar Broad Absorption Line Quasars found in DPOSS

    CERN Document Server

    Brunner, R J; Djorgovski, S G; Gal, R R; Mahabal, A A; Lopes, P A A; De Carvalho, R R; Odewahn, S C; Castro, S; Thompson, D; Chaffee, F; Darling, J; Desai, V; Brunner, Robert J.; Hall, Patrick B.

    2003-01-01

    With the recent release of large (i.e., > hundred million objects), well-calibrated photometric surveys, such as DPOSS, 2MASS, and SDSS, spectroscopic identification of important targets is no longer a simple issue. In order to enhance the returns from a spectroscopic survey, candidate sources are often preferentially selected to be of interest, such as brown dwarfs or high redshift quasars. This approach, while useful for targeted projects, risks missing new or unusual species. We have, as a result, taken the alternative path of spectroscopically identifying interesting sources with the sole criterion being that they are in low density areas of the g - r and r - i color-space defined by the DPOSS survey. In this paper, we present three peculiar broad absorption line quasars that were discovered during this spectroscopic survey, demonstrating the efficacy of this approach. PSS J0052+2405 is an Iron LoBAL quasar at a redshift z = 2.4512 with very broad absorption from many species. PSS J0141+3334 is a reddened...

  5. Spectral decomposition of broad-line agns and host galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Vanden Berk, Daniel E.; Shen, Jiajian; /Penn State U., Astron. Astrophys.; Yip, Ching-Wa; /Pittsburgh U.; Schneider, Donald P.; /Penn State U., Astron. Astrophys.; Connolly,; /Pittsburgh U.; Burton, Ross E.; /Pittsburgh U. /Case Western Reserve U.; Jester, Sebastian; /Fermilab; Hall, Patrick B.; /York U., Canada; Szalay, Alex S.; /Johns Hopkins; Brinkmann, John; /Apache Point Observ.

    2005-09-01

    Using an eigenspectrum decomposition technique, we separate the host galaxy from the broad line active galactic nucleus (AGN) in a set of 4666 spectra from the Sloan Digital Sky Survey (SDSS), from redshifts near zero up to about 0.75. The decomposition technique uses separate sets of galaxy and quasar eigenspectra to efficiently and reliably separate the AGN and host spectroscopic components. The technique accurately reproduces the host galaxy spectrum, its contributing fraction, and its classification. We show how the accuracy of the decomposition depends upon S/N, host galaxy fraction, and the galaxy class. Based on the eigencoefficients, the sample of SDSS broad-line AGN host galaxies spans a wide range of spectral types, but the distribution differs significantly from inactive galaxies. In particular, post-starburst activity appears to be much more common among AGN host galaxies. The luminosities of the hosts are much higher than expected for normal early-type galaxies, and their colors become increasingly bluer than early-type galaxies with increasing host luminosity. Most of the AGNs with detected hosts are emitting at between 1% and 10% of their estimated Eddington luminosities, but the sensitivity of the technique usually does not extend to the Eddington limit. There are mild correlations among the AGN and host galaxy eigencoefficients, possibly indicating a link between recent star formation and the onset of AGN activity. The catalog of spectral reconstruction parameters is available as an electronic table.

  6. Automatic and controlled processing and the Broad Autism Phenotype.

    Science.gov (United States)

    Camodeca, Amy; Voelker, Sylvia

    2016-01-30

    Research related to verbal fluency in the Broad Autism Phenotype (BAP) is limited and dated, but generally suggests intact abilities in the context of weaknesses in other areas of executive function (Hughes et al., 1999; Wong et al., 2006; Delorme et al., 2007). Controlled processing, the generation of search strategies after initial, automated responses are exhausted (Spat, 2013), has yet to be investigated in the BAP, and may be evidenced in verbal fluency tasks. One hundred twenty-nine participants completed the Delis-Kaplan Executive Function System Verbal Fluency test (D-KEFS; Delis et al., 2001) and the Broad Autism Phenotype Questionnaire (BAPQ; Hurley et al., 2007). The BAP group (n=53) produced significantly fewer total words during the 2nd 15" interval compared to the Non-BAP (n=76) group. Partial correlations indicated similar relations between verbal fluency variables for each group. Regression analyses predicting 2nd 15" interval scores suggested differentiation between controlled and automatic processing skills in both groups. Results suggest adequate automatic processing, but slowed development of controlled processing strategies in the BAP, and provide evidence for similar underlying cognitive constructs for both groups. Controlled processing was predictive of Block Design score for Non-BAP participants, and was predictive of Pragmatic Language score on the BAPQ for BAP participants. These results are similar to past research related to strengths and weaknesses in the BAP, respectively, and suggest that controlled processing strategy use may be required in instances of weak lower-level skills. PMID:26652842

  7. Broad-band solar bursts of the spike type

    International Nuclear Information System (INIS)

    Observations of high-resolution dynamic spectra of solar broad-band spike bursts (BSB), consisting of the instantaneous brightening of the continuum in the entire spectrograph range of 175-235 MHz, are reported. In noise storms events of the BSB type are rarely encountered and have the form of individual bursts with an average duration of 0.1-0.2 sec or groups of such bursts connected with type III bursts at lower frequencies. Series of aperiodic BSB structures unconnected with type III bursts and observed together with one-second pulsations and fiber bursts, predominate in type IV bursts. In noise storms BSB bursts can be emitted by electrons accelerated instantaneously as a result of the reconnection of magnetic fields, both in a small source (about 10 to the 8th cm) with a broad velocity dispersion and in an extended source (about 5 x 10 to the 9th cm). Structures of the BSB type in type IV bursts may be the result of the scattering of Langmuir waves on whistlers in a large height range. 30 references

  8. Broad-band solar bursts of the spike type

    Energy Technology Data Exchange (ETDEWEB)

    Bakunin, L.M.; Chernov, G.P.

    1985-10-01

    Observations of high-resolution dynamic spectra of solar broad-band spike bursts (BSB), consisting of the instantaneous brightening of the continuum in the entire spectrograph range of 175-235 MHz, are reported. In noise storms events of the BSB type are rarely encountered and have the form of individual bursts with an average duration of 0.1-0.2 sec or groups of such bursts connected with type III bursts at lower frequencies. Series of aperiodic BSB structures unconnected with type III bursts and observed together with one-second pulsations and fiber bursts, predominate in type IV bursts. In noise storms BSB bursts can be emitted by electrons accelerated instantaneously as a result of the reconnection of magnetic fields, both in a small source (about 10 to the 8th cm) with a broad velocity dispersion and in an extended source (about 5 x 10 to the 9th cm). Structures of the BSB type in type IV bursts may be the result of the scattering of Langmuir waves on whistlers in a large height range. 30 references.

  9. Broad spectrum microarray for fingerprint-based bacterial species identification

    Directory of Open Access Journals (Sweden)

    Frey Jürg E

    2010-02-01

    Full Text Available Abstract Background Microarrays are powerful tools for DNA-based molecular diagnostics and identification of pathogens. Most target a limited range of organisms and are based on only one or a very few genes for specific identification. Such microarrays are limited to organisms for which specific probes are available, and often have difficulty discriminating closely related taxa. We have developed an alternative broad-spectrum microarray that employs hybridisation fingerprints generated by high-density anonymous markers distributed over the entire genome for identification based on comparison to a reference database. Results A high-density microarray carrying 95,000 unique 13-mer probes was designed. Optimized methods were developed to deliver reproducible hybridisation patterns that enabled confident discrimination of bacteria at the species, subspecies, and strain levels. High correlation coefficients were achieved between replicates. A sub-selection of 12,071 probes, determined by ANOVA and class prediction analysis, enabled the discrimination of all samples in our panel. Mismatch probe hybridisation was observed but was found to have no effect on the discriminatory capacity of our system. Conclusions These results indicate the potential of our genome chip for reliable identification of a wide range of bacterial taxa at the subspecies level without laborious prior sequencing and probe design. With its high resolution capacity, our proof-of-principle chip demonstrates great potential as a tool for molecular diagnostics of broad taxonomic groups.

  10. Effect of gamma irradiation on antinutritional factors in broad bean

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the level of antinutritional factors (trypsin inhibitor (TI), phytic acid and oligosaccharides) of broad bean was investigated. The seeds were subjected to gamma irradiation at 0, 2.5, 5, 7.5 and 10 kGy, respectively using cobalt-60 gamma radiation with a dose rate 2.37 kGy/h. TI activity was reduced by 4.5%, 6.7%, 8.5% and 9.2% at 2.5, 5, 7.5 and 10 kGy, respectively. Meanwhile, irradiation at 10.2, 12.3, 15.4 and 18.2 kGy reduced the phytic acid content. The flatulence causing oligosaccharides were decreased as the radiation dose increased. The chemical composition (protein, oil, ash and total carbohydrates) of the tested seeds was determined. Gamma radiation seems to be a good procedure to improve the quality of broad bean from the nutritional point of view

  11. Effect of gamma irradiation on antinutritional factors in broad bean

    Science.gov (United States)

    Al-Kaisey, Mahdi T.; Alwan, Abdul-Kader H.; Mohammad, Manal H.; Saeed, Amjed H.

    2003-06-01

    The effect of gamma irradiation on the level of antinutritional factors (trypsin inhibitor (TI), phytic acid and oligosaccharides) of broad bean was investigated. The seeds were subjected to gamma irradiation at 0, 2.5, 5, 7.5 and 10 kGy, respectively using cobalt-60 gamma radiation with a dose rate 2.37 kGy/h. TI activity was reduced by 4.5%, 6.7%, 8.5% and 9.2% at 2.5, 5, 7.5 and 10 kGy, respectively. Meanwhile, irradiation at 10.2, 12.3, 15.4 and 18.2 kGy reduced the phytic acid content. The flatulence causing oligosaccharides were decreased as the radiation dose increased. The chemical composition (protein, oil, ash and total carbohydrates) of the tested seeds was determined. Gamma radiation seems to be a good procedure to improve the quality of broad bean from the nutritional point of view.

  12. Involvement of the crustacean hyperglycemic hormone (CHH) in the physiological compensation of the freshwater crayfish Cherax quadricarinatus to low temperature and high salinity stress.

    Science.gov (United States)

    Prymaczok, Natalia C; Pasqualino, Valeria M; Viau, Verónica E; Rodríguez, Enrique M; Medesani, Daniel A

    2016-02-01

    This study was aimed at determining the role of the crustacean hyperglycemic hormone (CHH) in the physiological compensation to both saline and thermal stress, in the freshwater crayfish Cherax quadricarinatus. By determining the expression of the CHH gene in the eyestalk of juvenile crayfish, we found that maximal induction of CHH was induced at high salinity (10 g/L) and low temperature (20 °C). In order to investigate the role of CHH in the physiological compensation to such stressful conditions, recombinant CHH was supplied to stressed animals. CHH-injected crayfish showed increased hemolymphatic levels of glucose, in accordance with a significant utilization of glycogen reserves from the hepatopancreas. Furthermore, CHH administration allowed stressed animals to regulate hemolymphatic sodium and potassium at more constant levels than controls. Taken together, these results suggest a relevant role of CHH in increasing the energy available intended for processes involved in the physiological compensation of C. quadricarinatus to both saline and thermal stress. PMID:26660884

  13. Concentrations and compositions of organochlorine contaminants in sediments, soils, crustaceans, fishes and birds collected from Lake Tai, Hangzhou Bay and Shanghai city region, China

    International Nuclear Information System (INIS)

    Contamination by persistent organochlorines (OCs), such as DDTs, hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) were examined in sediments, soils, fishes, crustaceans, birds, and aquaculture feed from Lake Tai, Hangzhou Bay, and in the vicinity of Shanghai city in China during 2000 and 2001. OCs were detected in all samples analyzed, and DDT and its metabolites were the predominant contaminants in most sediments, soils and biota. Concentrations of p,p'-DDT and ratio of p,p'-DDT to ΣDDTs were significantly higher in marine fishes than those in freshwater fishes. While the use of DDTs has been officially banned in China since 1983, these results indicate a recent input of technical DDTs into the marine environment around Hangzhou Bay. Comparison of organochlorine concentrations in fishes collected from Lake Tai and Hangzhou Bay suggests the presence of local sources of HCHs, chlordanes and PCBs at Lake Tai. Higher proportions of penta- and hexa-PCB congeners in fishes at Lake Tai may suggest the use of highly chlorinated PCB product, such as PCB5, around this lake. To our knowledge, this is a first comprehensive study to examine the present status of organochlorine contamination in various environmental media, such as sediments, soils and wildlife, in China. - Elevated concentrations of DDTs were detected in sediments, soils, and wildlife collected from China

  14. History and sensitivity comparison of two standard whole-sediment toxicity tests with crustaceans: the amphipod Hyalella azteca and the ostracod Heterocypris incongruens microbiotest

    Directory of Open Access Journals (Sweden)

    De Cooman W.

    2015-01-01

    Full Text Available The review first details the development of the test procedures with Hyalella azteca which historically emerged as one of the recommended test species for whole-sediment assays and its gradual standardization and endorsement by national and international organizations. The sensitivity and precision of the H. azteca test for application on chemicals and on real world sediments is discussed. The review subsequently addresses the development of the whole sediment microbiotest with the ostracod crustacean Heterocypris incongruens with larvae of this test species hatched from dormant eggs (cysts, rendering this assay stock culture/maintenance free. The application of the 6-day ostracod microbiotest on sediments in Canada and in Belgium is discussed, as well as its endorsement by the ISO subsequent to an extensive international interlaboratory ring test. The sensitivity of the amphipod and ostracod tests is compared by data from studies in which both assays were applied in parallel. A comparison of more than 1000 ostracod/amphipod data pairs of a 12-year river sediment monitoring study in Flanders/Belgium confirmed that both whole-sediment assays have a similar sensitivity and that the 6-day ostracod microbiotest is a valuable and cost-effective alternative to the 10−14 day amphipod test for evaluation of the toxic hazard of polluted sediments.

  15. Putative pacemakers in the eyestalk and brain of the crayfish Procambarus clarkii show circadian oscillations in levels of mRNA for crustacean hyperglycemic hormone.

    Directory of Open Access Journals (Sweden)

    Janikua Nelson-Mora

    Full Text Available Crustacean hyperglycemic hormone (CHH synthesizing cells in the optic lobe, one of the pacemakers of the circadian system, have been shown to be present in crayfish. However, the presence of CHH in the central brain, another putative pacemaker of the multi-oscillatory circadian system, of this decapod and its circadian transcription in the optic lobe and brain have yet to be explored. Therefore, using qualitative and quantitative PCR, we isolated and cloned a CHH mRNA fragment from two putative pacemakers of the multi-oscillatory circadian system of Procambarus clarkii, the optic lobe and the central brain. This CHH transcript synchronized to daily light-dark cycles and oscillated under dark, constant conditions demonstrating statistically significant daily and circadian rhythms in both structures. Furthermore, to investigate the presence of the peptide in the central brain of this decapod, we used immunohistochemical methods. Confocal microscopy revealed the presence of CHH-IR in fibers and cells of the protocerebral and tritocerebal clusters and neuropiles, particularly in some neurons located in clusters 6, 14, 15 and 17. The presence of CHH positive neurons in structures of P. clarkii where clock proteins have been reported suggests a relationship between the circadian clockwork and CHH. This work provides new insights into the circadian regulation of CHH, a pleiotropic hormone that regulates many physiological processes such as glucose metabolism and osmoregulatory responses to stress.

  16. EXPOSURE ASSESSMENT TO FOOD CONTAMINANTS ON EDIBLE FISH, CLAMS AND CRUSTACEANS IN A COASTAL ENVIRONMENT FACING A MINING AND INDUSTRIAL AREA IN SARDINIA (SULCIS-IGLESIENTE

    Directory of Open Access Journals (Sweden)

    P.L. Piras

    2011-08-01

    Full Text Available The risk assessment following exposure of the local population to the consumption of fishery products caught in the Boi Cerbus lagoon, located in country of Portoscuso (Sardinia, followed the phase of sampling, analysis and data-collection “site-specific”. Overall, the fishery products samples are part of the following zoological groups: fish (grey mullets, soles and gobies, bivalve (cockles and crustaceans (crabs. It was also agreed that further investigation were implemented in a targeted way, directing attention to critical issues that emerged from the first phase, represented by heavy metals such as Cadmium, Lead, Mercury and the (metalloid Arsenic that, for the purposes of food safety, are still contaminants with high concern for the potential impact on human health. For the risk analysis through food intake, three different procedures for exposure assessment were considered: the regulation by law, the assessment according to US-EPA approach and the assessment according to EU harmonized method. For a wider opportunity for exposure assessment through ingestion of food from contaminated areas, also for their risk management, a single approach to the risk analysis is not be considered sufficient.

  17. Trophic transfer of trace metals from the polychaete worm Nereis diversicolor to the polychaete N. virens and the decapod crustacean Palaemonetes varians

    Science.gov (United States)

    Rainbow, P.S.; Poirier, L.; Smith, B.D.; Brix, K.V.; Luoma, S.N.

    2006-01-01

    Diet is an important exposure route for the uptake of trace metals by aquatic invertebrates, with trace metal trophic transfer depending on 2 stages - assimilation and subsequent accumulation by the predator. This study investigated the trophic transfer of trace metals from the sediment-dwelling polychaete worm Nereis diversicolor from metal-rich estuarine sediments in southwestern UK to 2 predators - another polychaete N. virens (Cu, Zn, Pb, Cd, Fe) and the decapod crustacean Palaemonetes varians (Cu, Zn, Pb, Cd, Fe, Ag, As, Mn). N. virens showed net accumulation of Cu, Zn, Pb and Cd from the prey; accumulation increased with increasing prey concentration, but a coefficient of trophic transfer decreased with increasing prey concentration, probably because a higher proportion of accumulated metal in the prey is bound in less trophically available (insoluble) detoxified forms. The trace metal accumulation patterns of P. varians apparently restricted significant net accumulation of metals from the diet of N. diversicolor to just Cd. There was significant mortality of the decapods fed on the diets of metal-rich worms. Metal-rich invertebrates that have accumulated metals from the rich historical store in the sediments of particular SW England estuaries can potentially pass these metals along food chains, with accumulation and total food chain transfer depending on the metal assimilation efficiencies and accumulation patterns of the animal at each trophic level. This trophic transfer may be significant enough to have ecotoxicological effects. ?? Inter-Research 2006.

  18. Public and Conservation Trust Lands

    Data.gov (United States)

    California Department of Resources — A 1:100,000 polygon features class representing public, conservation and trust land ownership in the state of California. Developed for the California Resources...

  19. Ergodicity of conservative communication networks

    OpenAIRE

    Botvich, Dmitri D.; Zamyatin, A. A.

    1992-01-01

    Projet MEVAL We analyze a communication network with several types of calls. For a wide class of conservative service disciplines, we give ergodicity criteria. Exponentially fast convergence to steady state is also proved.

  20. Contests In Conservation and Horticulture

    Science.gov (United States)

    Jones, Richard D.

    1977-01-01

    Growing interest in conservation and horticulture in New York State has caused the addition of these specialized areas to the annual statewide agricultural education contests. Contest categories in both areas are listed. (MF)

  1. Diversity in conserved genes in tomato

    Directory of Open Access Journals (Sweden)

    Liu Jia

    2007-12-01

    Full Text Available Abstract Background Tomato has excellent genetic and genomic resources including a broad set of Expressed Sequence Tag (EST data and high-density genetic maps. In addition, emerging physical maps and bacterial artificial clone sequence data serve as template to investigate genetic variation within the cultivated germplasm pool with the goal to manipulate agriculturally important traits. Unfortunately, the nearly exclusive focus of resource development on interspecific populations for genetic analyses and diversity studies has left a void in our understanding of genotypic variation within tomato breeding programs that focus on intra-specific populations. We describe the results of a study to identify nucleotide variation within tomato breeding germplasm and mapping parents for a set of conserved single-copy ESTs that are orthologous between tomato and Arabidopsis. Results Using a pooled sequencing strategy, 967 tomato transcripts were screened for polymorphism in 12 tomato lines. Although intron position was conserved, intron lengths were 2-fold larger in tomato than in Arabidopsis. A total of 1,487 single nucleotide polymorphisms and 282 insertion/deletions were identified, of which 579 and 206 were polymorphic in breeding germplasm, respectively. Fresh market and processing germplasm were clearly divergent, as were Solanum lycopersicum var. cerasiformae and Solanum pimpinellifolium, tomato's closest relatives. The polymorphisms identified serve as marker resources for tomato. The COS is also applicable to other Solanaceae crops. Conclusions The results from this research enabled significant progress towards bridging the gap between genetic and genomic resources developed for populations derived from wide crosses and those applicable to intra-specific crosses for breeding in tomato.

  2. Diversity in conserved genes in tomato

    Science.gov (United States)

    Van Deynze, Allen; Stoffel, Kevin; Buell, C Robin; Kozik, Alexander; Liu, Jia; van der Knaap, Esther; Francis, David

    2007-01-01

    Background Tomato has excellent genetic and genomic resources including a broad set of Expressed Sequence Tag (EST) data and high-density genetic maps. In addition, emerging physical maps and bacterial artificial clone sequence data serve as template to investigate genetic variation within the cultivated germplasm pool with the goal to manipulate agriculturally important traits. Unfortunately, the nearly exclusive focus of resource development on interspecific populations for genetic analyses and diversity studies has left a void in our understanding of genotypic variation within tomato breeding programs that focus on intra-specific populations. We describe the results of a study to identify nucleotide variation within tomato breeding germplasm and mapping parents for a set of conserved single-copy ESTs that are orthologous between tomato and Arabidopsis. Results Using a pooled sequencing strategy, 967 tomato transcripts were screened for polymorphism in 12 tomato lines. Although intron position was conserved, intron lengths were 2-fold larger in tomato than in Arabidopsis. A total of 1,487 single nucleotide polymorphisms and 282 insertion/deletions were identified, of which 579 and 206 were polymorphic in breeding germplasm, respectively. Fresh market and processing germplasm were clearly divergent, as were Solanum lycopersicum var. cerasiformae and Solanum pimpinellifolium, tomato's closest relatives. The polymorphisms identified serve as marker resources for tomato. The COS is also applicable to other Solanaceae crops. Conclusions The results from this research enabled significant progress towards bridging the gap between genetic and genomic resources developed for populations derived from wide crosses and those applicable to intra-specific crosses for breeding in tomato. PMID:18088428

  3. Fundamental Constants and Conservation Laws

    OpenAIRE

    Roh, Heui-Seol

    2001-01-01

    This work describes underlying features of the universe such as fundamental constants and cosmological parameters, conservation laws, baryon and lepton asymmetries, etc. in the context of local gauge theories for fundamental forces under the constraint of the flat universe. Conservation laws for fundamental forces are related to gauge theories for fundamental forces, their resulting fundamental constants are quantitatively analyzed, and their possible violations at different energy scales are...

  4. Linearization of conservative nonlinear oscillators

    International Nuclear Information System (INIS)

    A linearization method of the nonlinear differential equation for conservative nonlinear oscillators is analysed and discussed. This scheme is based on the Chebyshev series expansion of the restoring force which allows us to obtain a frequency-amplitude relation which is valid not only for small but also for large amplitudes and, sometimes, for the complete range of oscillation amplitudes. Some conservative nonlinear oscillators are analysed to illustrate the usefulness and effectiveness of the technique

  5. Genomic toolboxes for conservation biologists

    OpenAIRE

    Angeloni, F.; Wagemaker, N.; Vergeer, P.; Ouborg, N.J.

    2011-01-01

    Conservation genetics is expanding its research horizon with a genomic approach, by incorporating the modern techniques of next-generation sequencing (NGS). Application of NGS overcomes many limitations of conservation genetics. First, NGS allows for genome-wide screening of markers, which may lead to a more representative estimation of genetic variation within and between populations. Second, NGS allows for distinction between neutral and non-neutral markers. By screening populations on thou...

  6. Pseudospin Conserving Shell Model Interactions

    OpenAIRE

    Ginocchio, Joseph N.

    2010-01-01

    Pseudospin symmetry is approximately conserved in nuclei. Normally shell model interactions are written in terms of spin an orbital angular momentum operators, not in terms of pseudospin and pseudo-orbital angular momentum operators. We determine the shell model interactions which conserve pseudospin symmetry and pseudo-orbital angular momentum symmetry and write them in terms of spin and orbital angular momentum operators including the tensor interaction. We show that, although the tensor in...

  7. Conservation laws of helical flows

    OpenAIRE

    Kelbin, Olga

    2015-01-01

    Helically symmetric flows are present in many technical devices such as wind turbine, combustion chamber and marine propeller. The understanding of the nature of this type of flow can be useful to describe such phenomena like a vortex breakdown. The aim of this thesis is the analytical investigation of helically symmetric flows in terms of conservation laws. After finding the conservation laws one is able to use the obtained theoretical results in order to construct exact solut...

  8. Growth Equation with Conservation Law

    OpenAIRE

    Lauritsen, Kent Baekgaard

    1995-01-01

    A growth equation with a generalized conservation law characterized by an integral kernel is introduced. The equation contains the Kardar-Parisi-Zhang, Sun-Guo-Grant, and Molecular-Beam Epitaxy growth equations as special cases and allows for a unified investigation of growth equations. From a dynamic renormalization-group analysis critical exponents and universality classes are determined for growth models with a conservation law.

  9. Conservation and the botanist effect

    DEFF Research Database (Denmark)

    Ahrends, Antje; Rahbek, Carsten; Bulling, Mark T.;

    2011-01-01

    practical training in tropical plant identification record both more species and more species of conservation concern (20 more species, two more endemic and one more threatened species per 250 specimens) than untrained botanists. Training and the number of person-days in the field explained 96% of the...... of botanists and in the provisioning of good facilities would substantially increase recording efficiency and data reliability, thereby improving conservation planning and implementation on the ground....

  10. Environment Education for Ecosystem Conservation

    OpenAIRE

    Ramachandra, TV

    2007-01-01

    Conservation of natural resources through sustainable ecosystem management and development is the key to our secured future. The management of ecosystem involves inventorying and monitoring, and applying integrated technologies, methodologies and interdisciplinary approaches for its conservation. Hence, now it is even more critical than ever before for the humans to be environmentally literate. To realise this vision, both ecological and environmental education must become a fundamental part ...

  11. 77 FR 74167 - Information Collection Request: Highly Erodible Land Conservation and Wetland Conservation

    Science.gov (United States)

    2012-12-13

    ... Farm Service Agency Information Collection Request: Highly Erodible Land Conservation and Wetland Conservation AGENCIES: Farm Service Agency, USDA. ACTION: Notice; request for comments. SUMMARY: In accordance... associated with Highly Erodible Land Conservation and Wetland Conservation certification requirements....

  12. 77 FR 32381 - Energy Conservation Program: Energy Conservation Standards for Residential Clothes Washers

    Science.gov (United States)

    2012-05-31

    ... and 430 RIN 1904-AB90 Energy Conservation Program: Energy Conservation Standards for Residential...: Proposed rule. SUMMARY: The Energy Policy and Conservation Act of 1975 (EPCA), as amended, prescribes energy conservation standards for various consumer products and certain commercial and...

  13. Targeted gene flow for conservation.

    Science.gov (United States)

    Kelly, Ella; Phillips, Ben L

    2016-04-01

    Anthropogenic threats often impose strong selection on affected populations, causing rapid evolutionary responses. Unfortunately, these adaptive responses are rarely harnessed for conservation. We suggest that conservation managers pay close attention to adaptive processes and geographic variation, with an eye to using them for conservation goals. Translocating pre-adapted individuals into recipient populations is currently considered a potentially important management tool in the face of climate change. Targeted gene flow, which involves moving individuals with favorable traits to areas where these traits would have a conservation benefit, could have a much broader application in conservation. Across a species' range there may be long-standing geographic variation in traits or variation may have rapidly developed in response to a threatening process. Targeted gene flow could be used to promote natural resistance to threats to increase species resilience. We suggest that targeted gene flow is a currently underappreciated strategy in conservation that has applications ranging from the management of invasive species and their impacts to controlling the impact and virulence of pathogens. PMID:26332195

  14. Conservation genetics of Iberian raptors

    Directory of Open Access Journals (Sweden)

    Martinez–Cruz, B.

    2011-12-01

    Full Text Available In this paper I provide an overview of conservation genetics and describe the management actions in the wild that can benefit from conservation genetic studies. I describe the genetic factors of risk for the survival of wild species, the consequences of loss of genetic diversity, inbreeding and outbreeding depression, and the use of genetic tools to delimitate units of conservation. Then I introduce the most common applications of conservation genetics in the management of wild populations. In a second part of the paper I review the conservation genetic studies carried on the Iberian raptors. I introduce several studies on the Spanish imperial eagle, the bearded vulture, the black vulture and the red kite that were carried out using autosomal microsatellite markers and mitochondrial DNA (mtDNA sequencing. I describe studies on the lesser kestrel and Egyptian vulture that additionally applied major histocompatibility complex (MHC markers, with the purpose of incorporating the study of non–neutral variation. For every species I explain how these studies can be and/or are applied in the strategy of conservation in the wild.

  15. The crucial contribution of veterinarians to conservation biology.

    Science.gov (United States)

    Reading, Richard P; Kenny, David E; Fitzgerald, Kevin T

    2013-11-01

    Conservation biology is a relatively new (began in the 1980s), value-based discipline predicated on the belief that biological diversity-from genes to populations to species to communities to ecosystems-is good and extinction is bad. Conservation biology grew from the recognition that the Earth has entered its sixth great extinction event, one that differs from previous great extinctions in that a single species-Homo sapiens-has caused this biodiversity crisis. A diverse, interacting set of variables drive current extinctions. As such, to succeed, conservation efforts usually require broad-based, interdisciplinary approaches. Conservationists increasingly recognize the importance of contributions by veterinary science, among many other disciplines, to collaborative efforts aimed at stemming the loss of biodiversity. We argue that, to improve success rates, many wildlife conservation programs must incorporate veterinarians as part of an interdisciplinary team to assess and address problems. Ideally, veterinarians who participate in conservation would receive specialized training and be willing to work as partners as part of a larger team of experts who effectively integrate their work rather than work independently (i.e., work as interdisciplinary, as opposed to multidisciplinary, teams, respectively). In our opinion, the most successful and productive projects involve interdisciplinary teams involving both biological and nonbiological specialists. Some researchers hold multiple degrees in biology and veterinary medicine or the biological and social sciences. These experts can often offer unique insight. We see at least 3 major areas in which veterinarians can immediately offer great assistance to conservation efforts: (1) participation in wildlife capture and immobilization, (2) leadership or assistance in addressing wildlife health issues, and (3) leadership or assistance in addressing wildlife disease issues, including using wildlife as sentinels to identify new

  16. Maximizing the ecological contribution of conservation banks

    OpenAIRE

    Bunn, DA; Moyle, PB; Johnson, CK

    2014-01-01

    In 1995, California established the first conservation banking program in the United States to provide a new financial mechanism to conserve wildlife and natural communities in rapidly developing regions. Conservation banks are lands protected and managed for conservation of species of concern. Developers may purchase species credits from a conservation bank to offset adverse impacts of development at another site. Conservation banks facilitate pooling of mitigation resources from multiple de...

  17. METALLOCENE POLYETHYLENES WITH BROAD OR BIMODAL MOLECULAR WEIGHT DISTRIBUTION

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Seven new binuclear titanocenes with different linking bridges, unsubstituted or substituted on the Cp rings, were synthesized and tested for their effect on ethylene polymerization in the presence of MAO. The polyethylenes thus obtained had broad MWD or even bimodal GPC curves, as compared with that from two reference mononuclear titanocenes. This is explained by the difference in degree of steric hindrance around the active center sites imposed by the bulky substituted ligands assuming different configurations in the rotation of the catalyst molecules. Lower polymerization temperatures alleviate the effect of these configuration differences, as reflected in change in MW and -Mw/-Mn. This effect is not caused by decomposition or disproportionation of the binuclear titanocenes as evidenced by the stability of the catalyst.

  18. Study of Coda Qc According to Broad Band Seismic Data

    International Nuclear Information System (INIS)

    The coda wave attenuation quality factor Qc at the Javakheti plateau and at the area located at the north of Tbilisi from 11 local earthquakes recorded by broad band seismograph have been estimated. The Qc was estimated using the single-scattering attenuation model in the frequency range from 0.62 to 40 Hz. The analyzed events were recorded at epicentral distances up to 80 km and their magnitudes vary from 2.5 to 4.3. In the north of Tbilisi we found that Qc=(100±15)f0.6 in the indicated frequency range and Qc=(100±15)f0.4 for the Javakheti Plateau in the frequency range from 40 to 10 Hz. (author)

  19. Radio Structures of Compact Quasars with Broad Absorption Lines

    Science.gov (United States)

    Kunert-Bajraszewska, Magdalena; Gawroński, Marcin P.

    2010-05-01

    Broad absorption lines (BALs), seen in a small fraction of both the radio-quiet and radio-loud quasar populations, are probably caused by the outflow of gas with high velocities and are part of the accretion process. The presence of BALs is due to a geometrical effect and/or it is connected with the quasar evolution. Using the final release of FIRST survey combined with a catalog of BAL QSOs from SDSS/DR3, we have constructed a new sample of compact radio-loud BAL QSOs, which constitutes the majority of radio-loud BAL QSOs. The main goal of this project is to study the origin of BALs by analysis of the BAL QSOs radio morphology, orientation, and jet evolution using the European VLBI Network (EVN) at 1.6 GHz and the Very Long Baseline Array (VLBA) at 5 and 8.4 GHz.

  20. Method for detection and imaging over a broad spectral range

    Science.gov (United States)

    Yefremenko, Volodymyr; Gordiyenko, Eduard; Pishko, legal representative, Olga; Novosad, Valentyn; Pishko, deceased; Vitalii

    2007-09-25

    A method of controlling the coordinate sensitivity in a superconducting microbolometer employs localized light, heating or magnetic field effects to form normal or mixed state regions on a superconducting film and to control the spatial location. Electron beam lithography and wet chemical etching were applied as pattern transfer processes in epitaxial Y--Ba--Cu--O films. Two different sensor designs were tested: (i) a 3 millimeter long and 40 micrometer wide stripe and (ii) a 1.25 millimeters long, and 50 micron wide meandering-like structure. Scanning the laser beam along the stripe leads to physical displacement of the sensitive area, and, therefore, may be used as a basis for imaging over a broad spectral range. Forming the superconducting film as a meandering structure provides the equivalent of a two-dimensional detector array. Advantages of this approach are simplicity of detector fabrication, and simplicity of the read-out process requiring only two electrical terminals.

  1. Optimization of the geometry of broad energy germanium detectors

    International Nuclear Information System (INIS)

    Broad energy germanium (BEGe) detectors are employed in many different scientific experiments and widely used in industrial applications. A circular contact is implanted on a base of the cylindrical shaped detector. This circular contact is used as a read out electrode and is surrounded by a passivated groove that separates it from the high voltage electrode, which spans over the remaining surface. The size of the read out electrode and the groove geometry are assumed to have a major impact onto the energy resolution, pulse shape discrimination and energy threshold. To quantify the impact of the detectors geometry on its performance, the read out contacts size of two BEGe detectors was modified several times. The geometry of the detector was optimized prior to each reprocessing step through the use of simulations. For each configuration, the detectors performance was analysed through distinct measurements. Some general consideration about analysis tools, simulation libraries and first results of this study are presented in this talk.

  2. Engineering broadly neutralizing antibodies for HIV prevention and therapy.

    Science.gov (United States)

    Hua, Casey K; Ackerman, Margaret E

    2016-08-01

    A combination of advances spanning from isolation to delivery of potent HIV-specific antibodies has begun to revolutionize understandings of antibody-mediated antiviral activity. As a result, the set of broadly neutralizing and highly protective antibodies has grown in number, diversity, potency, and breadth of viral recognition and neutralization. These antibodies are now being further enhanced by rational engineering of their anti-HIV activities and coupled to cutting edge gene delivery and strategies to optimize their pharmacokinetics and biodistribution. As a result, the prospects for clinical use of HIV-specific antibodies to treat, clear, and prevent HIV infection are gaining momentum. Here we discuss the diverse methods whereby antibodies are being optimized for neutralization potency and breadth, biodistribution, pharmacokinetics, and effector function with the aim of revolutionizing HIV treatment and prevention options. PMID:26827912

  3. Broad carbon monoxide line wings near T Tauri stars

    International Nuclear Information System (INIS)

    We report observations of carbon monoxide (CO) toward 26 T Tauri stars and related objects. In 19 of these objects, broad CO line wings of intensity > or approx. =0.1 K were detected, implying mass outflow is a common phenomenon in T Tauri stars. The velocity width (full width) of the wings ranges from 10 to 80 km s-1 and clusters around 25 km s-1. In general, the line wings are asymmetric with respect to the line core and the sense of asymmetry varies among sources. In the case of T Tauri, which has the broadest wing detected in these sources, the sense of wing asymmetry varies with position and may be due to source geometry

  4. Viroid Intercellular Trafficking: RNA Motifs, Cellular Factors and Broad Impacts

    Directory of Open Access Journals (Sweden)

    Ryuta Takeda

    2009-09-01

    Full Text Available Viroids are noncoding RNAs that infect plants. In order to establish systemic infection, these RNAs must traffic from an initially infected host cell into neighboring cells and ultimately throughout a whole plant. Recent studies have identified structural motifs in a viroid that are required for trafficking, enabling further studies on the mechanisms of their function. Some cellular proteins interact with viroids in vivo and may play a role in viroid trafficking, which can now be directly tested by using a virus-induced gene silencing system that functions efficiently in plant species from which these factors were identified. This review discusses these recent advances, unanswered questions and the use of viroid infection as an highly productive model to elucidate mechanisms of RNA trafficking that is of broad biological significance.

  5. Broad beam and narrow beam attenuation in Lipowitz's metal.

    Science.gov (United States)

    el-Khatib, E E; Podgorsak, E B; Pla, C

    1987-01-01

    Attenuation properties of Lipowitz's metal have been studied for narrow and broad beams of cobalt-60 gamma rays and 4-10 MV x-rays. The measured transmitted fraction for geometries used in radiotherapy depends on the field size and depth of measurement. Therefore a calculation of dose for partially attenuated beams based on narrow beam attenuation coefficients can cause large errors in dosimetry. Our simple calculation of transmitted fractions based on primary attenuation and scattered radiation agrees quite well with the measured data for therapeutic geometries. Also given is a table for linear, mass attenuation, and mass energy absorption coefficients of Lipowitz's metal in the photon energy range from 10 keV to 10 MeV. PMID:3104738

  6. Optimization of the geometry of broad energy germanium detectors

    Energy Technology Data Exchange (ETDEWEB)

    Salathe, Marco [Max Planck Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

    2015-07-01

    Broad energy germanium (BEGe) detectors are employed in many different scientific experiments and widely used in industrial applications. A circular contact is implanted on a base of the cylindrical shaped detector. This circular contact is used as a read out electrode and is surrounded by a passivated groove that separates it from the high voltage electrode, which spans over the remaining surface. The size of the read out electrode and the groove geometry are assumed to have a major impact onto the energy resolution, pulse shape discrimination and energy threshold. To quantify the impact of the detectors geometry on its performance, the read out contacts size of two BEGe detectors was modified several times. The geometry of the detector was optimized prior to each reprocessing step through the use of simulations. For each configuration, the detectors performance was analysed through distinct measurements. Some general consideration about analysis tools, simulation libraries and first results of this study are presented in this talk.

  7. Oxysterols: An emerging class of broad spectrum antiviral effectors.

    Science.gov (United States)

    Lembo, David; Cagno, Valeria; Civra, Andrea; Poli, Giuseppe

    2016-06-01

    Oxysterols are a family of cholesterol oxidation derivatives that contain an additional hydroxyl, epoxide or ketone group in the sterol nucleus and/or a hydroxyl group in the side chain. The majority of oxysterols in the blood are of endogenous origin, derived from cholesterol via either enzymatic or non-enzymatic mechanisms. A large number of reports demonstrate multiple physiological roles of specific oxysterols. One such role is the inhibition of viral replication. This biochemical/biological property was first characterised against a number of viruses endowed with an external lipid membrane (enveloped viruses), although antiviral activity has since been observed in relation to several non-enveloped viruses. In the present paper, we review the recent findings about the broad antiviral activity of oxysterols against enveloped and non-enveloped human viral pathogens, and provide an overview of their putative antiviral mechnism(s). PMID:27086126

  8. Genetically Engineered Broad-Spectrum Disease Resistance in Tomato

    Science.gov (United States)

    Oldroyd, Giles E. D.; Staskawicz, Brian J.

    1998-08-01

    Resistance in tomato to the bacterial pathogen Pseudomonas syringae pathovar tomato requires Pto and Prf. Mutations that eliminate Prf show a loss of both Pto resistance and sensitivity to the organophosphate insecticide fenthion, suggesting that Prf controls both phenotypes. Herein, we report that the overexpression of Prf leads to enhanced resistance to a number of normally virulent bacterial and viral pathogens and leads to increased sensitivity to fenthion. These plants express levels of salicylic acid comparable to plants induced for systemic acquired resistance (SAR) and constitutively express pathogenesis related genes. These results suggest that the overexpression of Prf activates the Pto and Fen pathways in a pathogen-independent manner and leads to the activation of SAR. Transgene-induced SAR has implications for the generation of broad spectrum disease resistance in agricultural crop plants.

  9. Outflow and hot dust emission in broad absorption line quasars

    International Nuclear Information System (INIS)

    We have investigated a sample of 2099 broad absorption line (BAL) quasars with z = 1.7-2.2 built from the Sloan Digital Sky Survey Data Release Seven and the Wide-field Infrared Survey. This sample is collected from two BAL quasar samples in the literature and is refined by our new algorithm. Correlations of outflow velocity and strength with a hot dust indicator (βNIR) and other quasar physical parameters—such as an Eddington ratio, luminosity, and a UV continuum slope—are explored in order to figure out which parameters drive outflows. Here βNIR is the near-infrared continuum slope, which is a good indicator of the amount of hot dust emission relative to the accretion disk emission. We confirm previous findings that outflow properties moderately or weakly depend on the Eddington ratio, UV slope, and luminosity. For the first time, we report moderate and significant correlations of outflow strength and velocity with βNIR in BAL quasars. It is consistent with the behavior of blueshifted broad emission lines in non-BAL quasars. The statistical analysis and composite spectra study both reveal that outflow strength and velocity are more strongly correlated with βNIR than the Eddington ratio, luminosity, and UV slope. In particular, the composites show that the entire C IV absorption profile shifts blueward and broadens as βNIR increases, while the Eddington ratio and UV slope only affect the high and low velocity part of outflows, respectively. We discuss several potential processes and suggest that the dusty outflow scenario, i.e., that dust is intrinsic to outflows and may contribute to the outflow acceleration, is most likely.

  10. Correlation between degradation and broadness of the transition in CICC

    Science.gov (United States)

    Martovetsky, Nicolai

    2013-10-01

    Cable in conduit conductor (CICC) performance is characterized in terms of relationships involving the electric field (E), voltage (V), temperature (T), current (I), magnetic field (B) and strain. Development of the electrical field in the V-T or V-I transitions in CICCs is exponential. These transitions plotted in the coordinates log E versus T or log E versus I look like straight lines. ITER Nb3Sn CICCs show degradation of properties versus load cycles that could be attributed to plastic deformation of the Nb3Sn strands or fracture of the superconducting filaments. The degradation is expressed in terms of the reduction of the current sharing temperature Tcs or critical current Ic, respectively. It was noticed long ago that degradation is accompanied by a significant broadening of the V-T or V-I transition, that looks like a change in the slope in the semi-log coordinate plot. This paper presents some systematic observations of correlations between the critical parameters and broadness of the transition in many CICCs. In most cases, the broadness of the transition seems to be a more sensitive indicator of the conductor damage even in cases where Tcs degradation is not clearly seen. Tcs degradation typically becomes obvious later in the cycling, especially after warm-up and following cool-down and more cycling. In some cases, a CICC manifests temporary or even a permanent growth of Tcs with load cycles, especially in the latest measurements of the CS conductors with short twist pitches. A possible mechanism of degradation that allows qualitative explanation of this phenomenon is discussed and is supported by the voltage measurements on the cable in the TFUS1 sample with the voltage taps penetrating the jacket to the cable.

  11. Evaluating local benefits from conservation in Nepal's Annapurna Conservation Area.

    Science.gov (United States)

    Spiteri, Arian; Nepal, Sanjay K

    2008-09-01

    Protected areas are integral to the global effort to conserve biodiversity, and, over the past two decades, protected area managers have begun to recognize that conservation objectives are next to impossible to achieve without considering the needs and concerns of local communities. Incentive-based programs (IBPs) have become a favored approach to protected area management, geared at fostering local stewardship by delivering benefits tied to conservation to local people. Effective IBPs require benefits to accrue to and be recognized by those experiencing the greatest consequences as a result of the protected area, and those likely to continue extractive activities if their livelihood needs are compromised. This research examines dispersal of IBP benefits, as perceived by local residents in Nepal's Annapurna Conservation Area. Results reported here are based on questionnaire interviews with 188 households conducted between September and December 2004. Results indicate that local residents primarily identify benefits from social development activities, provisions for resource extraction, and economic opportunities. Overall, benefits have been dispersed equally to households in villages on and off the main tourist route, and regardless of a household's participation in tourism. However, benefits are not effectively targeted to poorer residents, those highly dependent on natural resources, and those experiencing the most crop damage and livestock loss from protected wildlife. This article provides several suggestions for improving the delivery of conservation incentives. PMID:18458999

  12. Agricultural Set-aside Programs and Grassland Birds: Insights from Broad-scale Population Trends

    Directory of Open Access Journals (Sweden)

    S. Riffell

    2008-10-01

    Full Text Available The Conservation Reserve Program (CRP is a voluntary set-aside program in the United States designed to amelioratesoil erosion, control crop overproduction, enhance water quality, and provide wildlife habitat by replacing crops with other forms of land cover. Because CRP includes primarily grass habitats, it has great potential to benefitdeclining North American grassland bird populations. We looked at the change in national and state population trends of grassland birds and related changes to cover-specific CRP variables (previous research grouped all CRP practices. Changes in national trends after the initiation of the CRP were inconclusive, but we observed signficant bird-CRP relations at the state level. Most bird-CRP relations were positive, except for some species associated with habitats that CRP replaced. Practice- and configuration-specific CRP variables were related to grassland bird trends, rather than a generic measure of all CRP types combined. Considering all CRP land as a single, distinct habitat type may obscure actual relations between birds and set-aside characteristics. Understanding and predictingthe effects of set-aside programs (like CRP or agri-environment schemes on grassland birds is complex and difficult. Because available broad-scale datasets are less than adequate, studies should be conducted at a variety of spatial and temporal scales.

  13. Structures of the Zika Virus Envelope Protein and Its Complex with a Flavivirus Broadly Protective Antibody.

    Science.gov (United States)

    Dai, Lianpan; Song, Jian; Lu, Xishan; Deng, Yong-Qiang; Musyoki, Abednego Moki; Cheng, Huijun; Zhang, Yanfang; Yuan, Yuan; Song, Hao; Haywood, Joel; Xiao, Haixia; Yan, Jinghua; Shi, Yi; Qin, Cheng-Feng; Qi, Jianxun; Gao, George F

    2016-05-11

    Zika virus (ZIKV), a mosquito-borne flavivirus, is a current global public health concern. The flavivirus envelope (E) glycoprotein is responsible for virus entry and represents a major target of neutralizing antibodies for other flaviviruses. Here, we report the structures of ZIKV E protein at 2.0 Å and in complex with a flavivirus broadly neutralizing murine antibody 2A10G6 at 3.0 Å. ZIKV-E resembles all the known flavivirus E structures but contains a unique, positively charged patch adjacent to the fusion loop region of the juxtaposed monomer, which may influence host attachment. The ZIKV-E-2A10G6 complex structure reveals antibody recognition of a highly conserved fusion loop. 2A10G6 binds to ZIKV-E with high affinity in vitro and neutralizes currently circulating ZIKV strains in vitro and in mice. The E protein fusion loop epitope represents a potential candidate for therapeutic antibodies against ZIKV. PMID:27158114

  14. Development of Broad-Spectrum Halomethyl Ketone Inhibitors Against Coronavirus Main Protease 3CL(pro)

    Energy Technology Data Exchange (ETDEWEB)

    Bacha,U.; Barilla, J.; Gabelli, S.; Kiso, Y.; Amzel, L.; Freire, E.

    2008-01-01

    Coronaviruses comprise a large group of RNA viruses with diverse host specificity. The emergence of highly pathogenic strains like the SARS coronavirus (SARS-CoV), and the discovery of two new coronaviruses, NL-63 and HKU1, corroborates the high rate of mutation and recombination that have enabled them to cross species barriers and infect novel hosts. For that reason, the development of broad-spectrum antivirals that are effective against several members of this family is highly desirable. This goal can be accomplished by designing inhibitors against a target, such as the main protease 3CLpro (Mpro), which is highly conserved among all coronaviruses. Here 3CLpro derived from the SARS-CoV was used as the primary target to identify a new class of inhibitors containing a halomethyl ketone warhead. The compounds are highly potent against SARS 3CLpro with Ki's as low as 300 nm. The crystal structure of the complex of one of the compounds with 3CLpro indicates that this inhibitor forms a thioether linkage between the halomethyl carbon of the warhead and the catalytic Cys 145. Furthermore, Structure Activity Relationship (SAR) studies of these compounds have led to the identification of a pharmacophore that accurately defines the essential molecular features required for the high affinity.

  15. Evidence for a conserved CCAP-signaling pathway controlling ecdysis in a hemimetabolous insect, Rhodnius prolixus

    Directory of Open Access Journals (Sweden)

    Do Hee eLee

    2013-11-01

    Full Text Available A vital feature in the success of Ecdysozoa is their ability to shed their exoskeleton (a process called ecdysis such that they can grow or change their morphology. In holometabolous insects, these behaviours are orchestrated by the sequential actions of neuropeptides, one of which is crustacean cardioactive peptide (CCAP. Little is known about the control of ecdysis in hemimetabolous insects. Here, we report that CCAP is essential for successful ecdysis in the hemimetabolous insect, Rhodnius prolixus; the vector of Chagas disease. The first indication of CCAP’s involvement in ecdysis was the observation of decreased staining intensity of CCAP-containing neurons immediately following ecdysis, indicative of the release of CCAP. The critical importance of the CCAP signaling pathway was further demonstrated by knockdown (as determined by qPCR and immunohistochemistry of the CCAP and CCAPR transcripts utilizing dsRNA. This technique reduced the staining intensity of CCAP-containing neurons, and knocked down the transcript levels by up to 92%, with lethal consequences to the insect. Insects with these transcripts knocked down had very high mortality (up to 84%, typically at the expected time of the ecdysis sequence, or had ecdysis extremely delayed. This is the first report of the susceptibility of R. prolixus to dsRNA knockdown of neuropeptide and receptor transcripts, and the data clearly demonstrates the conserved nature of the CCAP signaling pathway in ecdysis between holometabolous and hemimetabolous insects.

  16. Water Conservation and Water Storage

    Science.gov (United States)

    Narayanan, M.

    2014-12-01

    Water storage can be a viable part of the solution to water conservation. This means that we should include reservoirs. Regardless, one should evaluate all aspects of water conservation principles. Recent drought in California indicates that there is an urgent need to re-visit the techniques used to maintain the water supply-chain mechanism in the entire state. We all recognize the fact that fish and wildlife depend on the streams, rivers and wetlands for survival. It is a well-known fact that there is an immediate need to provide solid protection to all these resources. Laws and regulations should help meet the needs of natural systems. Farmers may be forced to drilling wells deeper than ever. But, they will be eventually depleting groundwater reserves. Needless to say that birds, fish and wildlife cannot access these groundwater table. California is talking a lot about conservation. Unfortunately, the conservation efforts have not established a strong visible hold. The Environmental Protection Agency has a plan called E2PLAN (Narayanan, 2012). It is EPA's plan for achieving energy and environmental performance, leadership, accountability, and carbon neutrality. In June 2011, the EPA published a comprehensive, multi-year planning document called Strategic Sustainability Performance Plan. The author has previously reported these in detail at the 2012 AGU fall meeting. References: Ziegler, Jay (15 JUNE 2014). The Conversation: Water conservation efforts aren't taking hold, but there are encouraging signs. THE SACRAMENTO BEE. California. Narayanan, Mysore. (2012). The Importance of Water Conservation in the 21st Century. 72nd AGU International Conference. Eos Transactions: American Geophysical Union, Vol. 92, No. 56, Fall Meeting Supplement, 2012. H31I - 1255.http://www.sacbee.com/2014/06/15/6479862/jay-ziegler-water-conservation.html#storylink=cpy

  17. High-Resolution Genuinely Multidimensional Solution of Conservation Laws by the Space-Time Conservation Element and Solution Element Method

    Science.gov (United States)

    Himansu, Ananda; Chang, Sin-Chung; Yu, Sheng-Tao; Wang, Xiao-Yen; Loh, Ching-Yuen; Jorgenson, Philip C. E.

    1999-01-01

    In this overview paper, we review the basic principles of the method of space-time conservation element and solution element for solving the conservation laws in one and two spatial dimensions. The present method is developed on the basis of local and global flux conservation in a space-time domain, in which space and time are treated in a unified manner. In contrast to the modern upwind schemes, the approach here does not use the Riemann solver and the reconstruction procedure as the building blocks. The drawbacks of the upwind approach, such as the difficulty of rationally extending the 1D scalar approach to systems of equations and particularly to multiple dimensions is here contrasted with the uniformity and ease of generalization of the Conservation Element and Solution Element (CE/SE) 1D scalar schemes to systems of equations and to multiple spatial dimensions. The assured compatibility with the simplest type of unstructured meshes, and the uniquely simple nonreflecting boundary conditions of the present method are also discussed. The present approach has yielded high-resolution shocks, rarefaction waves, acoustic waves, vortices, ZND detonation waves, and shock/acoustic waves/vortices interactions. Moreover, since no directional splitting is employed, numerical resolution of two-dimensional calculations is comparable to that of the one-dimensional calculations. Some sample applications displaying the strengths and broad applicability of the CE/SE method are reviewed.

  18. Conserved Endonuclease Function of Hantavirus L Polymerase

    Directory of Open Access Journals (Sweden)

    Sylvia Rothenberger

    2016-05-01

    Full Text Available Hantaviruses are important emerging pathogens belonging to the Bunyaviridae family. Like other segmented negative strand RNA viruses, the RNA-dependent RNA polymerase (RdRp also known as L protein of hantaviruses lacks an intrinsic “capping activity”. Hantaviruses therefore employ a “cap snatching” strategy acquiring short 5′ RNA sequences bearing 5′cap structures by endonucleolytic cleavage from host cell transcripts. The viral endonuclease activity implicated in cap snatching of hantaviruses has been mapped to the N-terminal domain of the L protein. Using a combination of molecular modeling and structure–function analysis we confirm and extend these findings providing evidence for high conservation of the L endonuclease between Old and New World hantaviruses. Recombinant hantavirus L endonuclease showed catalytic activity and a defined cation preference shared by other viral endonucleases. Based on the previously reported remarkably high activity of hantavirus L endonuclease, we established a cell-based assay for the hantavirus endonuclase function. The robustness of the assay and its high-throughput compatible format makes it suitable for small molecule drug screens to identify novel inhibitors of hantavirus endonuclease. Based on the high degree of similarity to RdRp endonucleases, some candidate inhibitors may be broadly active against hantaviruses and other emerging human pathogenic Bunyaviruses.

  19. Conserved Endonuclease Function of Hantavirus L Polymerase.

    Science.gov (United States)

    Rothenberger, Sylvia; Torriani, Giulia; Johansson, Maria U; Kunz, Stefan; Engler, Olivier

    2016-01-01

    Hantaviruses are important emerging pathogens belonging to the Bunyaviridae family. Like other segmented negative strand RNA viruses, the RNA-dependent RNA polymerase (RdRp) also known as L protein of hantaviruses lacks an intrinsic "capping activity". Hantaviruses therefore employ a "cap snatching" strategy acquiring short 5' RNA sequences bearing 5'cap structures by endonucleolytic cleavage from host cell transcripts. The viral endonuclease activity implicated in cap snatching of hantaviruses has been mapped to the N-terminal domain of the L protein. Using a combination of molecular modeling and structure-function analysis we confirm and extend these findings providing evidence for high conservation of the L endonuclease between Old and New World hantaviruses. Recombinant hantavirus L endonuclease showed catalytic activity and a defined cation preference shared by other viral endonucleases. Based on the previously reported remarkably high activity of hantavirus L endonuclease, we established a cell-based assay for the hantavirus endonuclase function. The robustness of the assay and its high-throughput compatible format makes it suitable for small molecule drug screens to identify novel inhibitors of hantavirus endonuclease. Based on the high degree of similarity to RdRp endonucleases, some candidate inhibitors may be broadly active against hantaviruses and other emerging human pathogenic Bunyaviruses. PMID:27144576

  20. Decentralizing conservation and diversifying livelihoods within Kanchenjunga Conservation Area, Nepal.

    Science.gov (United States)

    Parker, Pete; Thapa, Brijesh; Jacob, Aerin

    2015-12-01

    To alleviate poverty and enhance conservation in resource dependent communities, managers must identify existing livelihood strategies and the associated factors that impede household access to livelihood assets. Researchers increasingly advocate reallocating management power from exclusionary central institutions to a decentralized system of management based on local and inclusive participation. However, it is yet to be shown if decentralizing conservation leads to diversified livelihoods within a protected area. The purpose of this study was to identify and assess factors affecting household livelihood diversification within Nepal's Kanchenjunga Conservation Area Project, the first protected area in Asia to decentralize conservation. We randomly surveyed 25% of Kanchenjunga households to assess household socioeconomic and demographic characteristics and access to livelihood assets. We used a cluster analysis with the ten most common income generating activities (both on- and off-farm) to group the strategies households use to diversify livelihoods, and a multinomial logistic regression to identify predictors of livelihood diversification. We found four distinct groups of household livelihood strategies with a range of diversification that directly corresponded to household income. The predictors of livelihood diversification were more related to pre-existing socioeconomic and demographic factors (e.g., more landholdings and livestock, fewer dependents, receiving remittances) than activities sponsored by decentralizing conservation (e.g., microcredit, training, education, interaction with project staff). Taken together, our findings indicate that without direct policies to target marginalized groups, decentralized conservation in Kanchenjunga will continue to exclude marginalized groups, limiting a household's ability to diversify their livelihood and perpetuating their dependence on natural resources. PMID:26363256

  1. The Conservation Status and Conservation Strategy of Picea neoveitchii

    Institute of Scientific and Technical Information of China (English)

    Zhang Deshun; Kim Yongshik; Mike Maunder; Li Xiufen

    2006-01-01

    Picea neoveitchii is an endemic species in China. It had been listed as an endangered species in red data books. It scatters in several locations of south slope of the Qinling Mountain of China. Upon reviewing the related literature, discussing with leading scholars on gymnosperm, ecology and plant conservation, the field survey was carried out in four locations. There are eleven mature individuals and two seedlings surviving in its natural habitats. With the survey of quadrat method in four locations, related community index were calculated such as relative important value (RIV), species richness,similarity index, diversity index and evenness index etc.The community could be sorted and characterized as three groups based on the community parameters. The analysis of vegetation table elucidates that Picea neoveitchii is a dominant species with low grouping rate in most surveyed sites.The RAPD analysis shows target species has intraspecific genetic variability. The estimation of Shannon's phenotypic diversity index (Ho) also explains the difference of genetic variations of different locations.Due to the lack of enough knowledge and professional guide of conservation biological perspective,Picea neoveitchii had been clear-cut for timber production. The extent of occurrence and area of occupancy declined rapidly from 1950s to 1990s.According to the Conservation Category guideline proposed by the World Conservation Union, the conservation status of Picea neoveitchii was reevaluated as Critically Endangered (CR) B2b C2a D. Upon research in areas of ecology, molecular biology, cluster analysis of environmental parameters, a practical conservation strategy is recommended in this research.

  2. Virilization of the Broad Line Region in Active Galactic Nuclei - connection between shifts and widths of broad emission lines

    CERN Document Server

    Jonic, Sanja; Ilic, Dragana; Popovic, Luka C

    2016-01-01

    We investigate the virilization of the emission lines Hbeta and Mg II in the sample of 287 Type 1 Active Galactic Nuclei taken from the Sloan Digital Sky Survey database. We explore the connections between the intrinsic line shifts and full widths at different levels of maximal intensity. We found that: (i) Hbeta seems to be a good virial estimator of black hole masses, and an intrinsic redshift of Hbeta is dominantly caused by the gravitational effect, (ii) there is an anti-correlation between the redshift and width of the wings of the Mg II line, (iii) the broad Mg II line can be used as virial estimator only at 50% of the maximal intensity, while the widths and intrinsic shifts of the line wings can not be used for this purpose.

  3. Survey to determine the adequacy of existing conserved areas in relation to vegetation types. A preliminary report.

    Directory of Open Access Journals (Sweden)

    D. Edwards

    1974-07-01

    Full Text Available The report is a broad survey of the conservation status of South African vegetation. Data and maps show the distribution and total areas of conserved lands by the various conservation agencies, the size structure of nature reserves, the areas and percentages of conserved areas in relation to the 70 veld types and seven main vegetation types into which South Africa was divided by Acocks (1953, and important conservation requirements in the Bantu Homelands. Major conservation deficiencies lie in the Karoo and Karroid Bushveld and Grassland Types of vegetation, where 42 veld types have none or virtually no conservation, and in the Tropical Bush and Savanna Types to which-belong nine of the 10 remaining veld types extremely lacking in conservation. Additional reserves are needed' to conserve certain important and local ecosystems and species in the remaining 18 veld types, especially the Sclerophyllous Bush (Macchia or Fynbos and Temperate and Transitional Forest and Scrub Types, and in certain Coastal Tropical Forest and Thornveld Types. Apart from minor deficiencies, the conservation status is outstanding for six of these 18 veld types (up to 47 per cent under conservation, and very good for another six veld types.

  4. Techniques in molecular spectroscopy: from broad bandwidth to high resolution

    Science.gov (United States)

    Cossel, Kevin C.

    This thesis presents a range of different experiments all seeking to extended the capabilities of molecular spectroscopy and enable new applications. The new technique of cavity-enhanced direct frequency comb spectroscopy (CE-DFCS) provides a unique combination of broad bandwidth, high resolution, and high sensitivity that can be useful for a wide range of applications. Previous demonstrations of CE-DFCS were confined to the visible or near-infrared and operated over a limited bandwidth: for many applications it is desirable to increase the spectral coverage and to extend to the mid-infrared where strong, fundamental vibrational modes of molecules occur. There are several key requirements for CE-DFCS: a frequency comb source that provides broad bandwidth and high resolution, an optical cavity for high sensitivity, and a detection system capable of multiplex detection of the comb spectrum transmitted through the cavity. We first discuss comb sources with emphasis on the coherence properties of spectral broadening in nonlinear fiber and the development of a high-power frequency comb source in the mid-infrared based on an optical-parametric oscillator (OPO). To take advantage of this new mid-infrared comb source for spectroscopy, we also discuss the development of a rapid-scan Fourier-transform spectrometer (FTS). We then discuss the first demonstration of CE-DFCS with spectrally broadened light from a highly nonlinear fiber with the application to measurements of impurities in semiconductor manufacturing gases. We also cover our efforts towards extending CE-DFCS to the mid-infrared using the mid-infrared OPO and FTS to measure ppb levels of various gases important for breath analysis and atmospheric chemistry and highlight some future applications of this system. In addition to the study of neutral molecules, broad-bandwidth and high-resolution spectra of molecular ions are useful for astrochemistry where many of the observed molecules are ionic, for studying

  5. Gap Analysis and Conservation Network for Freshwater Wetlands in Central Yangtze Ecoregion

    Directory of Open Access Journals (Sweden)

    Li Xiaowen

    2013-01-01

    Full Text Available The Central Yangtze Ecoregion contains a large area of internationally important freshwater wetlands and supports a huge number of endangered waterbirds; however, these unique wetlands and the biodiversity they support are under the constant threats of human development pressures, and the prevailing conservation strategies generated based on the local scale cannot adequately be used as guidelines for ecoregion-based conservation initiatives for Central Yangtze at the broad scale. This paper aims at establishing and optimizing an ecological network for freshwater wetland conservation in the Central Yangtze Ecoregion based on large-scale gap analysis. A group of focal species and GIS-based extrapolation technique were employed to identify the potential habitats and conservation gaps, and the optimized conservation network was then established by combining existing protective system and identified conservation gaps. Our results show that only 23.49% of the potential habitats of the focal species have been included in the existing nature reserves in the Central Yangtze Ecoregion. To effectively conserve over 80% of the potential habitats for the focal species by optimizing the existing conservation network for the freshwater wetlands in Central Yangtze Ecoregion, it is necessary to establish new wetland nature reserves in 22 county units across Hubei, Anhui, and Jiangxi provinces.

  6. Conservative regularization of compressible flow

    CERN Document Server

    Krishnaswami, Govind S; Thyagaraja, Anantanarayanan

    2015-01-01

    Ideal Eulerian flow may develop singularities in vorticity w. Navier-Stokes viscosity provides a dissipative regularization. We find a local, conservative regularization - lambda^2 w times curl(w) of compressible flow and compressible MHD: a three dimensional analogue of the KdV regularization of the one dimensional kinematic wave equation. The regulator lambda is a field subject to the constitutive relation lambda^2 rho = constant. Lambda is like a position-dependent mean-free path. Our regularization preserves Galilean, parity and time-reversal symmetries. We identify locally conserved energy, helicity, linear and angular momenta and boundary conditions ensuring their global conservation. Enstrophy is shown to remain bounded. A swirl velocity field is identified, which transports w/rho and B/rho generalizing the Kelvin-Helmholtz and Alfven theorems. A Hamiltonian and Poisson bracket formulation is given. The regularized equations are used to model a rotating vortex, channel flow, plane flow, a plane vortex ...

  7. The Conservation of Panel paintings

    DEFF Research Database (Denmark)

    imperative to strengthen scientific research into the production methods, ageing and future behaviour of panel paintings, being an intricate interplay between different materials. A deeper understanding of the processes that adversely affect panel paintings over time will contribute to the improved care and...... damage caused by unstable environmental conditions. Unfortunately, past structural interventions often caused significant damage due to insufficient knowledge of the behaviour of the wood panels, glue and paint layers. Over the last fifty years, the field has developed treatment strategies based on...... interdisciplinary collaboration and on the knowledge of specialist conservators. Most current conservation protocols rely on empirical knowledge of conservators and are not necessarily based on a scientific understanding of the nature and behaviour of wood and paint layers. In order to move the field forward, it is...

  8. Community Forestry and Forest Conservation

    DEFF Research Database (Denmark)

    Milhøj, Anders; Casse, Thorkil

    2011-01-01

    This paper is a meta-study of local forest management experiences in developing countries drawn from a review of 56 case-studies presented in 52 papers. Many case-studies report positive links between community forestry and forest conservation. In international organizations and NGOs there is a...... generally accepted agreement that collective management (community forestry) will yield success in forest conservation. However, the claim is seldom rigorously examined. We suggest to have a review of the literature and to propose a first step to a test of the claim in order to reach a first generalization...... as to the success of community forestry in forest conservation. The review of the literature is the first step towards such an examination, enabling us to make some initial generalizations for further research. In the present paper, a statistical test is performed and the claim is found wanting. The...

  9. Quality control in breast conservation

    International Nuclear Information System (INIS)

    Over the past 15 years, breast conservation has become an accepted option for treatment of Stages I and II carcinoma of the breast; in this practice in 1991, more than 80% of these patients were treated in this manner. A surgical procedure to excise the primary lesion and to dissect the axilla is generally required to prepare patients for breast conservation, concurrently maximizing esthetic appearance of the breast, minimizing the risk of local recurrence and providing appropriate information for recommendations concerning adjuvant therapy. The volume of breast tissue to be removed, significance of findings at surgical margins, and extent of the axillary dissection are all somewhat controversial subjects. Based upon a personal series of almost 800 patients undergoing breast conservation, observations that reflect the findings from this experience may be shared. (author)

  10. Where has all our research gone? A 20-year assessment of the peer-reviewed wildlife conservation literature

    OpenAIRE

    Cronin, Drew Timothy; Owens, Jake R; Choi, Halle; Hromada, Steven; Malhotra, Rumaan; Roser, Faith; Bergl, Richard

    2014-01-01

    We conducted a review of the wildlife conservation literature to identify broad trends in the publishing record and focal areas of research over the past 20 years. A total of 5,853 papers were reviewed with an emphasis on decadal changes between 1993, 2002, and 2012. For each paper we identified the journal and common keywords, and also determined the research scope, conservation issues and applications, and geographic focus. We found that both the numer of journals publishing in the field, a...

  11. Biological effects of the anti-parasitic chemotherapeutant emamectin benzoate on a non-target crustacean, the spot prawn (Pandalus platyceros Brandt, 1851) under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Veldhoen, Nik [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, Stn CSC, Victoria, BC, V8W 3P6 (Canada); Ikonomou, Michael G. [Institute of Ocean Sciences, Fisheries and Oceans Canada, 9860 West Saanich Road, P.O. Box 6000, Sidney, BC, V8L 4B2 (Canada); Buday, Craig [Pacific Environmental Science Centre, Environment Canada, 2645 Dollarton Highway, North Vancouver, BC, V7H 1V2 (Canada); Jordan, Jameson; Rehaume, Vicki; Cabecinha, Melissa [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, Stn CSC, Victoria, BC, V8W 3P6 (Canada); Dubetz, Cory; Chamberlain, Jon [Institute of Ocean Sciences, Fisheries and Oceans Canada, 9860 West Saanich Road, P.O. Box 6000, Sidney, BC, V8L 4B2 (Canada); Pittroff, Sabrina; Vallee, Kurtis [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, Stn CSC, Victoria, BC, V8W 3P6 (Canada); Aggelen, Graham van [Pacific Environmental Science Centre, Environment Canada, 2645 Dollarton Highway, North Vancouver, BC, V7H 1V2 (Canada); Helbing, Caren C., E-mail: chelbing@uvic.ca [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055, Stn CSC, Victoria, BC, V8W 3P6 (Canada)

    2012-02-15

    The potential impact of commercial salmon aquaculture along the coast of British Columbia on the health of non-target marine wildlife is of growing concern. In the current initiative, the biological effects on gene expression within spot prawn (Pandalus platyceros) exposed to the sea lice controlling agent, emamectin benzoate (EB; 0.1-4.8 mg/kg sediment), were investigated. A mean sediment/water partitioning coefficient (K{sub p}) was determined to be 21.81 and significant levels of EB were detected in the tail muscle tissue in all exposed animals. Animals selected for the experiment did not have eggs and were of similar weight. Significant mortality was observed within 8 days of EB treatment at concentrations between 0.1 and 0.8 mg/kg and there was no effect of EB on molting. Twelve spot prawn cDNA sequences were isolated from the tail muscle either by directed cloning or subtractive hybridization of control versus EB exposed tissues. Three of the transcripts most affected by EB exposure matched sequences encoding the 60S ribosomal protein L22, spliceosome RNA helicase WM6/UAP56, and the intracellular signal mediator histidine triad nucleotide binding protein 1 suggesting that translation, transcription regulation, and apoptosis pathways were impacted. The mRNA encoding the molting enzyme, {beta}-N-acetylglucosaminidase, was not affected by EB treatment. However, the expression of this transcript was extremely variable making it unsuitable for effects assessment. The results suggest that short-term exposure to EB can impact biological processes within this non-target crustacean.

  12. Recommended reporting standards for test accuracy studies of infectious diseases of finfish, amphibians, molluscs and crustaceans: the STRADAS-aquatic checklist.

    Science.gov (United States)

    Gardner, Ian A; Whittington, Richard J; Caraguel, Charles G B; Hick, Paul; Moody, Nicholas J G; Corbeil, Serge; Garver, Kyle A; Warg, Janet V; Arzul, Isabelle; Purcell, Maureen K; Crane, Mark St J; Waltzek, Thomas B; Olesen, Niels J; Gallardo Lagno, Alicia

    2016-02-25

    Complete and transparent reporting of key elements of diagnostic accuracy studies for infectious diseases in cultured and wild aquatic animals benefits end-users of these tests, enabling the rational design of surveillance programs, the assessment of test results from clinical cases and comparisons of diagnostic test performance. Based on deficiencies in the Standards for Reporting of Diagnostic Accuracy (STARD) guidelines identified in a prior finfish study (Gardner et al. 2014), we adapted the Standards for Reporting of Animal Diagnostic Accuracy Studies-paratuberculosis (STRADAS-paraTB) checklist of 25 reporting items to increase their relevance to finfish, amphibians, molluscs, and crustaceans and provided examples and explanations for each item. The checklist, known as STRADAS-aquatic, was developed and refined by an expert group of 14 transdisciplinary scientists with experience in test evaluation studies using field and experimental samples, in operation of reference laboratories for aquatic animal pathogens, and in development of international aquatic animal health policy. The main changes to the STRADAS-paraTB checklist were to nomenclature related to the species, the addition of guidelines for experimental challenge studies, and the designation of some items as relevant only to experimental studies and ante-mortem tests. We believe that adoption of these guidelines will improve reporting of primary studies of test accuracy for aquatic animal diseases and facilitate assessment of their fitness-for-purpose. Given the importance of diagnostic tests to underpin the Sanitary and Phytosanitary agreement of the World Trade Organization, the principles outlined in this paper should be applied to other World Organisation for Animal Health (OIE)-relevant species. PMID:26912041

  13. Neurogenesis in the central olfactory pathway of adult decapod crustaceans: development of the neurogenic niche in the brains of procambarid crayfish

    Directory of Open Access Journals (Sweden)

    Sintoni Silvia

    2012-01-01

    Full Text Available Abstract Background In the decapod crustacean brain, neurogenesis persists throughout the animal's life. After embryogenesis, the central olfactory pathway integrates newborn olfactory local and projection interneurons that replace old neurons or expand the existing population. In crayfish, these neurons are the descendants of precursor cells residing in a neurogenic niche. In this paper, the development of the niche was documented by monitoring proliferating cells with S-phase-specific markers combined with immunohistochemical, dye-injection and pulse-chase experiments. Results Between the end of embryogenesis and throughout the first post-embryonic stage (POI, a defined transverse band of mitotically active cells (which we will term 'the deutocerebral proliferative system' (DPS appears. Just prior to hatching and in parallel with the formation of the DPS, the anlagen of the niche appears, closely associated with the vasculature. When the hatchling molts to the second post-embryonic stage (POII, the DPS differentiates into the lateral (LPZ and medial (MPZ proliferative zones. The LPZ and MPZ are characterized by a high number of mitotically active cells from the beginning of post-embryonic life; in contrast, the developing niche contains only very few dividing cells, a characteristic that persists in the adult organism. Conclusions Our data suggest that the LPZ and MPZ are largely responsible for the production of new neurons in the early post-embryonic stages, and that the neurogenic niche in the beginning plays a subordinate role. However, as the neuroblasts in the proliferation zones disappear during early post-embryonic life, the neuronal precursors in the niche gradually become the dominant and only mechanism for the generation of new neurons in the adult brain.

  14. Decapod crustaceans from the state of Ceará, northeastern Brazil: an updated checklist of marine and estuarine species, with 23 new records.

    Science.gov (United States)

    Pachelle, Paulo P G; Anker, Arthur; Mendes, Cecili B; Bezerra, Luis E A

    2016-01-01

    The present study is the first major assessment of the marine decapod fauna of Ceará, northeastern Brazil, since contributions of J. Fausto-Filho in the 1960s-1970s. A fully updated checklist of all decapod crustaceans occurring in marine and estuarine habitats of Ceará is provided, based on literature records, specimens held in two carcinological collections of the Universidade Federal do Ceará (UFC), and material collected mainly by the authors between 2011 and 2014. A total of 337 decapod species are listed, distributed among the following taxa: Achelata (8 species), Anomura (42 species), Astacidea (1 species), Axiidea (11 species), Brachyura (162 species), Caridea (83 species), Dendrobranchiata (20 species), Gebiidea (9 species), and Stenopodidea (1 species). Among them, 23 species represent new records for Ceará, with 14 species, viz. Alpheus peasei (Armstrong, 1940), A. thomasi Hendrix & Gore, 1973, Ambidexter symmetricus Manning & Chace, 1971, Axianassa australis Rodrigues & Shimizu, 1992, Biffarius biformis (Biffar, 1971), B. fragilis (Biffar, 1970), Leptalpheus axianassae Dworschak & Coelho, 1999, L. forceps Williams, 1965, Lysmata bahia Rhyne & Lin, 2006, L. intermedia (Kingsley, 1878), Merhippolyte americana Holthuis, 1961, Neocallichirus maryae Karasawa, 2004, Ogyrides hayi Williams, 1981, and Typton carneus Holthuis, 1951, now having Ceará as the northern-most limit in their distribution range along the Brazilian coastline. One shrimp species, Lysmata lipkei Okuno & Fiedler, 2010, which was also found in the state of Rio Grande do Norte, possibly represents an invasive taxon in Brazil and the western Atlantic, originating from the Indo-West Pacific. Alpheus buckupi Almeida, Terossi, Araújo-Silva & Mantelatto, 2013, previously recorded from Ceará based on a colour photograph, is confirmed from this state, with specimens from several new localities. A few doubtful records from Ceará are briefly discussed. Colour photographs are provided for most

  15. Biological effects of the anti-parasitic chemotherapeutant emamectin benzoate on a non-target crustacean, the spot prawn (Pandalus platyceros Brandt, 1851) under laboratory conditions

    International Nuclear Information System (INIS)

    The potential impact of commercial salmon aquaculture along the coast of British Columbia on the health of non-target marine wildlife is of growing concern. In the current initiative, the biological effects on gene expression within spot prawn (Pandalus platyceros) exposed to the sea lice controlling agent, emamectin benzoate (EB; 0.1–4.8 mg/kg sediment), were investigated. A mean sediment/water partitioning coefficient (Kp) was determined to be 21.81 and significant levels of EB were detected in the tail muscle tissue in all exposed animals. Animals selected for the experiment did not have eggs and were of similar weight. Significant mortality was observed within 8 days of EB treatment at concentrations between 0.1 and 0.8 mg/kg and there was no effect of EB on molting. Twelve spot prawn cDNA sequences were isolated from the tail muscle either by directed cloning or subtractive hybridization of control versus EB exposed tissues. Three of the transcripts most affected by EB exposure matched sequences encoding the 60S ribosomal protein L22, spliceosome RNA helicase WM6/UAP56, and the intracellular signal mediator histidine triad nucleotide binding protein 1 suggesting that translation, transcription regulation, and apoptosis pathways were impacted. The mRNA encoding the molting enzyme, β-N-acetylglucosaminidase, was not affected by EB treatment. However, the expression of this transcript was extremely variable making it unsuitable for effects assessment. The results suggest that short-term exposure to EB can impact biological processes within this non-target crustacean.

  16. The community of deep-sea decapod crustaceans between 175 and 2600 m in submarine canyons of a volcanic oceanic island (central-eastern Atlantic)

    Science.gov (United States)

    Pajuelo, José G.; Triay-Portella, Raül; Santana, José I.; González, José A.

    2015-11-01

    The community structure and faunal composition of deep-sea decapod crustaceans in submarine canyons on the slope off Gran Canaria Island (Canary Islands, central-eastern Atlantic) were investigated. Samples were collected during five research cruises (115 stations) at depths between 175 and 2554 m. A total of 26387 decapod specimens, belonging to 24 families and 38 species, were collected with traps. A cluster analysis of the stations showed four distinct assemblages: (i) in the transition area between shelf and slope (175-302 m); (ii) on the upper slope (361-789 m); (iii) on the middle slope (803-1973 m); and iv) on the lower slope (2011-2554 m). The deep-sea decapod fauna of the Canary Islands is dominated by shrimp of the family Pandalidae, which make up more than 23% of the species. Within the Pandalidae, species of the genus Plesionika stand out as those of greatest abundance on the island slope. The greatest diversity of species was located on the upper slope. The standardized mean abundance and mean biomass for the transition zone between the shelf and slope and for the upper slope were nearly 5 times greater in abundance and 4 times greater in biomass than those estimated for the middle slope, and nearly 53 and 29 times greater for the lower slope, indicating a lower abundance and biomass at the shallower part of the insular slope. The mean weight per individual showed an increasing pattern with depth and an inverse pattern with the bottom temperature and salinity. The existence of depth boundaries around the Canary Islands is known to be closely linked to oceanographic conditions, determined by the water masses present in this archipelago explaining the discontinuities observed at depths of 800 and 2000 m. The boundary observed inside the bathymetric region of the Eastern North Atlantic Central Water can be related with the transition zone between the shelf and the slope of the island.

  17. Quantification of emerging micropollutants in an amphipod crustacean by nanoliquid chromatography coupled to mass spectrometry using multiple reaction monitoring cubed mode.

    Science.gov (United States)

    Sordet, Martin; Berlioz-Barbier, Alexandra; Buleté, Audrey; Garric, Jeanne; Vulliet, Emmanuelle

    2016-07-22

    An innovative analytical method has been developed to quantify the bioaccumulation in an amphipod crustacean (Gammarus fossarum) of three micropollutants regarded as anthropic-pollution markers: carbamazepine, oxazepam, and testosterone. A liquid-liquid extraction assisted by salts, known as QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) was miniaturised and optimised, so it could be adapted to the low mass samples (approximatively 5mg dry weight). For this same reason and in order to obtain good sensitivity, ultra-trace analyses were carried out by means of nanoliquid chromatography. A preconcentration system by on-column trapping was optimised to increase the injection volume. In order to improve both sensitivity and selectivity, the multiple reaction monitoring cubed mode analyses (MRM(3)) were carried out, validated and compared to the classic MRM. To the best of our knowledge, this is the first time that MRM(3) is coupled to nanoliquid chromatography for the analysis and detection of organic micropollutants <300Da. The optimised extraction method exhibited recoveries superior to 80%. The limits of quantification of the target compounds were 0.3, 0.7 and 4.7ng/g (wet weight) for oxazepam, carbamazepine and testosterone, respectively and the limits of detection were 0.1, 0.3 and 2.2ng/g (wet weight), respectively. The intra- and inter-day precisions were inferior to 7.7% and 10.9%, respectively, for the three levels of concentration tested. The analytical strategy developed allowed to obtain limits of quantification lower than 1ng/g (wet weight) and to establish the kinetic bioconcentration of contaminants within G. fossarum. PMID:27324621

  18. Fermion number conservation isn't fermion conservation

    International Nuclear Information System (INIS)

    A nonperturbative regularization of the Standard Model may have a superficially undesirable exact global U(1) symmetry corresponding to exact fermion number conservation. We argue that such a formulation can still have the desired physics of fermion nonconservation, i.e. fermion particle creation and annihilation by sphaleron transitions. We illustrate our reasoning in massless axial QED in 1+1 dimensions. (orig.)

  19. Backyard Conservation: Bringing Conservation from the Countryside to Your Backyard.

    Science.gov (United States)

    Wildlife Habitat Council, Silver Spring, MD.

    This guide highlights 10 conservation activities, adapted from farms and ranches, that can be used in the backyard. Each activity provides background information and instructions on how to complete the activity. The activities concern: (1) tree planting; (2) wildlife habitat; (3) backyard ponds; (4) nutrient management; (5) terracing; (6) water…

  20. Delayed metamorphosis in decapod crustaceans: evidence and consequences Retraso de la metamorfosis en crustáceos decápodos: evidencias y consecuencias

    Directory of Open Access Journals (Sweden)

    PAULINA GEBAUER

    2003-06-01

    Full Text Available Most marine invertebrate species exhibit a complex life cycle including a planktonic larval phase and a benthic juvenile-adult phase. Metamorphosis and settlement are the links between these phases of development. In many species, metamorphosis is triggered by specific chemical and/or physical cues, mainly associated with the adult habitat. In the absence of such cues, competent larvae can delay their metamorphosis by a few days to several months. Most investigations on the delay of metamorphosis have been realised on sessile or sedentary species. In relation to mobile decapod crustaceans, the number of such studies is low, probably because the members of this group retain their mobility after metamorphosis, and hence, may depend less on enviromental cues for the induction of settlement and metamorphosis. Nevertheless, the larvae of some decapod species have been shown to depend on metamorphosis-stimulating cues. These include special types of substrates, physical or chemical traits of particular (e.g., estuarine water bodies, as well as odors from conspecific or congeneric adults. The capacity for delay is, in the decapod species studied so far, limited and may normally end with spontaneous metamorphosis. An extended time of larval development presents the advantage of enhancing the probability for locating a suitable habitat, but it may imply, as a disadvantage, a reduction of juvenile growth or survival and a prolonged development time preceding benthic life. This paper reviews the available evidence for delayed metamorphosis in decapod crustaceans, indentifed cues, the importance of larval age at the time of contact with a cue, and costs of delayed metamorphosis. Additionally, we propose new frontiers for future investigations on delayed metamorphosis in decapod crustaceans, including the molecular identification of chemical cues, the identification of the stage(s of the moulting cycle that is or are sensitive to such cues, the study of