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Sample records for metamorphosis biological

  1. Biological factors controlling developmental duration, growth and metamorphosis of the larval green toad, Bufo viridis viridis

    Directory of Open Access Journals (Sweden)

    Gamal A. Bekhet

    2014-05-01

    Full Text Available The present study in a controlled laboratory setting provided important insights into both the degree of plasticity and the proximal environmental cues operating in the response of green toad tadpoles to pond drying, food level. It was concluded that timing of metamorphosis and size at metamorphosis were highly affected by pond duration. The effects of pond desiccation are reflected by shorter developmental duration and smaller size at metamorphosis as a result of increased crowding in the shallow tanks than tadpoles in the deep tanks. Bufo viridis raised on high food supplements grew faster than those raised on low food in low or high population density. In the tanks with decreased water and food levels, the tadpoles accelerate development and metamorphose earlier than tadpoles in higher food and water levels. The obtained data revealed that tadpoles grew faster under conditions of high population density than low one in either high or low food levels. Actual density had limited but significant effects on tadpole size and development. It also suggested that density regulation, acting on the tadpole stage, may be present in the population but was of less short-term importance than abiotic factors. Environmentally induced variation in developmental rates translated to changes in relative hind leg length. Hind leg length plasticity was positively correlated with growth rate plasticity. Finally, documenting the recent results of this study, B. viridis breed in temporary ponds and exhibited plasticity in developmental duration and growth rate in response to a change in water level.

  2. Metamorphosis in Craniiformea revisited

    DEFF Research Database (Denmark)

    Altenburger, Andreas; Wanninger, Andreas; Holmer, Lars E.

    2013-01-01

    We revisited the brachiopod fold hypothesis and investigated metamorphosis in the craniiform brachiopod Novocrania anomala. Larval development is lecithotrophic and the dorsal (brachial) valve is secreted by dorsal epithelia. We found that the juvenile ventral valve, which consists only of a thin....... We show that the “brachiopod fold hypothesis,” which argues that brachiopods are transversely “folded” across the ontogenetic anterior–posterior axis, should be rejected at least with respect to the craniiforms. The data now suggest that the Craniiformea may be a derived group within......), such as a through-gut and missing hinge articulation, may thus be secondarily derived characters of the Craniiformea within the Rhynchonelliformea....

  3. Transformations of Aortic Arches During Metamorphosis of the Spade-Foot Toad, Pelobates fuscus

    Czech Academy of Sciences Publication Activity Database

    Majorová, H.; Roček, Zbyněk

    2004-01-01

    Roč. 260, č. 3 (2004), s. 309 ISSN 0362-2525. [International Congress of Vertebrate Morphology /7./. 27.07.2004-01.08.2004, Boca Raton] Keywords : Anura * Circulatory System * Metamorphosis Subject RIV: EA - Cell Biology

  4. The phylogeny of amphibian metamorphosis.

    Science.gov (United States)

    Reiss, John O

    2002-01-01

    Frogs have one of the most extreme metamorphoses among vertebrates. How did this metamorphosis evolve? By combining the methods previously proposed by Mabee and Humphries (1993) and Velhagen (1997), I develop a phylogenetic method suited for rigorous analysis of this question. In a preliminary analysis using 12 transformation sequence characters and 36 associated event sequence characters, all drawn from the osteology of the skull, the evolution of metamorphosis is traced on an assumed phylogeny. This phylogeny has lissamphibians (frogs, salamanders, and caecilians) monophyletic, with frogs the sister group of salamanders. Successive outgroups used are temnospondyls and discosauriscids, both of which are fossil groups for which ontogenetic data are available. In the reconstruction of character evolution, an unambiguous change (synapomorphy) along the branch leading to lissamphibians is a delay in the lengthening of the maxilla until metamorphosis, in accordance with my previous suggestion (Reiss, 1996). However, widening of the interpterygoid vacuity does not appear as a synapomophy of lissamphibians, due to variation in the character states in the outgroups. From a more theoretical perspective, the reconstructed evolution of amphibian metamorphosis involves examples of heterochrony, through the shift of ancestral premetamorphic events to the metamorphic period, caenogenesis, through the origin of new larval features, and terminal addition, through the origin of new adult features. Other changes don't readily fit these categories. This preliminary study provides evidence that metamorphic changes in frogs arose as further modifications of changes unique to lissamphibians, as well as a new method by which such questions can be examined.

  5. Amphibian haematology: Metamorphosis-related changes in blood cells

    DEFF Research Database (Denmark)

    Rosenkilde, Per; Sørensen, Inger; Ussing, Anne Phaff

    1995-01-01

    Zoofysiologi, Amphibian metamorphosis, Haematology, Immunosuppression, Immunological Tolerance, Protozoan Infection, metamorfose, springpadder, ontogenese, halepadder.......Zoofysiologi, Amphibian metamorphosis, Haematology, Immunosuppression, Immunological Tolerance, Protozoan Infection, metamorfose, springpadder, ontogenese, halepadder....

  6. Mechanisms of tail resorption during anuran metamorphosis.

    Science.gov (United States)

    Nakai, Yuya; Nakajima, Keisuke; Yaoita, Yoshio

    2017-09-26

    Amphibian metamorphosis has historically attracted a good deal of scientific attention owing to its dramatic nature and easy observability. However, the genetic mechanisms of amphibian metamorphosis have not been thoroughly examined using modern techniques such as gene cloning, DNA sequencing, polymerase chain reaction or genomic editing. Here, we review the current state of knowledge regarding molecular mechanisms underlying tadpole tail resorption.

  7. Metamorphosis

    DEFF Research Database (Denmark)

    Parigi, Dario

    2015-01-01

    the constructional logic of reciprocal structures within the Grasshopper parametric design environment, and the KRS algorithm, a software for the design of free form kinetic reciprocal structure, both developed by the author, and coupled with structural form finding processes. The pavilion incorporates novel digital...

  8. Metamorphosis

    Science.gov (United States)

    Balch, Stephen H.

    2012-01-01

    One thing history's torrent appears to be sweeping away is, ironically, the study of its most productive wellspring, Western civilization. "The Vanishing West", a report the National Association of Scholars released in May 2011, documents the extent of this vanishing. The traditional Western civilization survey requirement, commonplace only…

  9. Posthuman Metamorphosis: Narrative and Systems, New

    Directory of Open Access Journals (Sweden)

    Elke D'hoker

    2009-10-01

    Full Text Available Review of Bruce Clarke, Posthuman Metamorphosis: Narrative and Systems, New
    York: Fordham University Press, 2008. 242 pages.
    978-0-8232-2580-8 (hardback
    978-0-8232-2581-5 (paperback

  10. Juvenile hormone resistance gene Methoprene-tolerant controls entry into metamorphosis in the beetle Tribolium castaneum

    Czech Academy of Sciences Publication Activity Database

    Konopová, Barbora; Jindra, Marek

    2007-01-01

    Roč. 104, - (2007), s. 10488-10493 ISSN 0027-8424 R&D Projects: GA AV ČR IAA5007305; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z50070508 Keywords : insect metamorphosis * postembryonic development * endocryne regulation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.598, year: 2007

  11. Structural Elements in Franz Kafka's "The Metamorphosis."

    Science.gov (United States)

    Johnson, Scott

    1993-01-01

    Notes that Kafka's "The Metamorphosis" is not only a masterpiece of modern literature but also a work that exemplifies many ideas of structural family therapy. Examines how Kafka's novella embodies concepts such as parentified children, enmeshment, intergenerational boundaries, coalitions and triangles, structural dysfunction, and…

  12. Broad-Complex acts downstream of Met in juvenile hormone signaling to coordinate primitive holometabolan metamorphosis

    Czech Academy of Sciences Publication Activity Database

    Konopová, Barbora; Jindra, Marek

    2008-01-01

    Roč. 135, č. 3 (2008), s. 559-568 ISSN 0950-1991 R&D Projects: GA ČR(CZ) GA204/07/1032; GA AV ČR IAA5007305; GA MŠk LC07032 Institutional research plan: CEZ:AV0Z50070508 Keywords : metamorphosis * juvenile hormone * broad-complex Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.812, year: 2008

  13. Proteomics insights: proteins related to larval attachment and metamorphosis of marine invertebrates

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2014-10-31

    The transition in an animal from a pelagic larval stage to a sessile benthic juvenile typically requires major morphological and behavioral changes. Larval competency, attachment and initiation of metamorphosis are thought to be regulated by intrinsic chemical signals and specific sets of proteins. However, the molecular mechanisms that regulate larval attachment and metamorphosis in marine invertebrates have yet to be fully elucidated. Despite the many challenges associated with analysis of the larvae proteome, recent proteomic technologies have been used to address specific questions in larval developmental biology. These and other molecular studies have generated substantial amount of information of the proteins and molecular pathways involved in larval attachment and metamorphosis. Furthermore, the results of these studies have shown that systematic changes in protein expression patterns and post-translational modifications (PTMs) are crucial for the transition from larva to juvenile. The degeneration of larval tissues is mediated by protein degradation, while the development of juvenile organs may require PTM. In terms of application, the identified proteins may serve as targets for antifouling compounds, and biomarkers for environmental stressors. In this review we highlight the strengths and limitations of proteomic tools in the context of the study of marine invertebrate larval biology.

  14. Phosphoproteome analysis during larval development and metamorphosis in the spionid polychaete Pseudopolydora vexillosa

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2011-05-25

    Background: The metamorphosis of the spionid polychaete Pseudopolydora vexillosa includes spontaneous settlement onto soft-bottom habitats and morphogenesis that can be completed in a very short time. A previous study on the total changes to the proteome during the various developmental stages of P. vexillosa suggested that little or no de novo protein synthesis occurs during metamorphosis. In this study, we used multicolor fluorescence detection of proteins in 2-D gels for differential analysis of proteins and phosphoproteins to reveal the dynamics of post-translational modification proteins in this species. A combination of affinity chromatography, 2D-PAGE, and mass spectrometry was used to identify the phosphoproteins in pre-competent larvae, competent larvae, and newly metamorphosed juveniles. Results: We reproducibly detected 210, 492, and 172 phosphoproteins in pre-competent larvae, competent larvae, and newly metamorphosed juveniles, respectively. The highest percentage of phosphorylation was observed during the competent larval stage. About 64 stage-specific phosphoprotein spots were detected in the competent stage, and 32 phosphoproteins were found to be significantly differentially expressed in the three stages. We identified 38 phosphoproteins, 10 of which were differentially expressed during metamorphosis. These phosphoproteins belonged to six categories of biological processes: (1) development, (2) cell differentiation and integrity, (3) transcription and translation, (4) metabolism, (5) protein-protein interaction and proteolysis, and (6) receptors and enzymes. Conclusion: This is the first study to report changes in phosphoprotein expression patterns during the metamorphosis of the marine polychaete P. vexillosa. The higher degree of phosphorylation during the process of attaining competence to settle and metamorphose may be due to fast morphological transitions regulated by various mechanisms. Our data are consistent with previous studies showing a

  15. The genetic covariance between life cycle stages separated by metamorphosis.

    Science.gov (United States)

    Aguirre, J David; Blows, Mark W; Marshall, Dustin J

    2014-08-07

    Metamorphosis is common in animals, yet the genetic associations between life cycle stages are poorly understood. Given the radical changes that occur at metamorphosis, selection may differ before and after metamorphosis, and the extent that genetic associations between pre- and post-metamorphic traits constrain evolutionary change is a subject of considerable interest. In some instances, metamorphosis may allow the genetic decoupling of life cycle stages, whereas in others, metamorphosis could allow complementary responses to selection across the life cycle. Using a diallel breeding design, we measured viability at four ontogenetic stages (embryo, larval, juvenile and adult viability), in the ascidian Ciona intestinalis and examined the orientation of additive genetic variation with respect to the metamorphic boundary. We found support for one eigenvector of G: (gobsmax ), which contrasted larval viability against embryo viability and juvenile viability. Target matrix rotation confirmed that while gobsmax shows genetic associations can extend beyond metamorphosis, there is still considerable scope for decoupled phenotypic evolution. Therefore, although genetic associations across metamorphosis could limit that range of phenotypes that are attainable, traits on either side of the metamorphic boundary are capable of some independent evolutionary change in response to the divergent conditions encountered during each life cycle stage. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  16. Metamorphosis of a butterfly-associated bacterial community.

    Directory of Open Access Journals (Sweden)

    Tobin J Hammer

    Full Text Available Butterflies are charismatic insects that have long been a focus of biological research. They are also habitats for microorganisms, yet these microbial symbionts are little-studied, despite their likely importance to butterfly ecology and evolution. In particular, the diversity and composition of the microbial communities inhabiting adult butterflies remain uncharacterized, and it is unknown how the larval (caterpillar and adult microbiota compare. To address these knowledge gaps, we used Illumina sequencing of 16S rRNA genes from internal bacterial communities associated with multiple life stages of the neotropical butterfly Heliconius erato. We found that the leaf-chewing larvae and nectar- and pollen-feeding adults of H. erato contain markedly distinct bacterial communities, a pattern presumably rooted in their distinct diets. Larvae and adult butterflies host relatively small and similar numbers of bacterial phylotypes, but few are common to both stages. The larval microbiota clearly simplifies and reorganizes during metamorphosis; thus, structural changes in a butterfly's bacterial community parallel those in its own morphology. We furthermore identify specific bacterial taxa that may mediate larval and adult feeding biology in Heliconius and other butterflies. Although male and female Heliconius adults differ in reproductive physiology and degree of pollen feeding, bacterial communities associated with H. erato are not sexually dimorphic. Lastly, we show that captive and wild individuals host different microbiota, a finding that may have important implications for the relevance of experimental studies using captive butterflies.

  17. Metamorphosis of a butterfly-associated bacterial community.

    Science.gov (United States)

    Hammer, Tobin J; McMillan, W Owen; Fierer, Noah

    2014-01-01

    Butterflies are charismatic insects that have long been a focus of biological research. They are also habitats for microorganisms, yet these microbial symbionts are little-studied, despite their likely importance to butterfly ecology and evolution. In particular, the diversity and composition of the microbial communities inhabiting adult butterflies remain uncharacterized, and it is unknown how the larval (caterpillar) and adult microbiota compare. To address these knowledge gaps, we used Illumina sequencing of 16S rRNA genes from internal bacterial communities associated with multiple life stages of the neotropical butterfly Heliconius erato. We found that the leaf-chewing larvae and nectar- and pollen-feeding adults of H. erato contain markedly distinct bacterial communities, a pattern presumably rooted in their distinct diets. Larvae and adult butterflies host relatively small and similar numbers of bacterial phylotypes, but few are common to both stages. The larval microbiota clearly simplifies and reorganizes during metamorphosis; thus, structural changes in a butterfly's bacterial community parallel those in its own morphology. We furthermore identify specific bacterial taxa that may mediate larval and adult feeding biology in Heliconius and other butterflies. Although male and female Heliconius adults differ in reproductive physiology and degree of pollen feeding, bacterial communities associated with H. erato are not sexually dimorphic. Lastly, we show that captive and wild individuals host different microbiota, a finding that may have important implications for the relevance of experimental studies using captive butterflies.

  18. 3D Object Metamorphosis with Pseudo Metameshes

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    MOCANU, B.

    2015-02-01

    Full Text Available In this paper we introduce a novel framework for 3D object metamorphosis, represented by closed triangular meshes. The systems returns a high quality transition sequence, smooth and gradual, that is visual pleasant and consistent to both source and target topologies. The method starts by parameterizing both the source and the target model to a common domain (the unit sphere. Then, the features selected from the two models are aligned by applying the CTPS C2a radial basis functions. We demonstrate how the selected approach can create valid warping by deforming the models embedded into the parametric domain. In the final stage, we propose and validate a novel algorithm to construct a pseudo-supermesh able to approximate both, the source and target 3D objects. By using the pseudo-supermesh we developed a morphing transition consistent with respect to both geometry and topology of the 3D models.

  19. A role for Taiman in insect metamorphosis.

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    Jesus Lozano

    2014-10-01

    Full Text Available Recent studies in vitro have reported that the Methoprene-tolerant (Met and Taiman (Tai complex is the functional receptor of juvenile hormone (JH. Experiments in vivo of Met depletion have confirmed this factor's role in JH signal transduction, however, there is no equivalent data regarding Tai because its depletion in larval or nymphal stages of the beetle Tribolium castaneum and the bug Pyrrhocoris apterus results in 100% mortality. We have discovered that the cockroach Blattella germanica possesses four Tai isoforms resulting from the combination of two indels in the C-terminal region of the sequence. The presence of one equivalent indel-1 in Tai sequences in T. castaneum and other species suggests that Tai isoforms may be common in insects. Concomitant depletion of all four Tai isoforms in B. germanica resulted in 100% mortality, but when only the insertion 1 (IN-1 isoforms were depleted, mortality was significantly reduced and about half of the specimens experienced precocious adult development. This shows that Tai isoforms containing IN-1 are involved in transducing the JH signal that represses metamorphosis. Reporter assays indicated that both T. castaneum Tai isoforms, one that contains the IN-1 and another that does not (DEL-1 activated a JH response element (kJHRE in Krüppel homolog 1 in conjunction with Met and JH. The results indicate that Tai is involved in the molecular mechanisms that repress metamorphosis, at least in B. germanica, and highlight the importance of distinguishing Tai isoforms when studying the functions of this transcription factor in development and other processes.

  20. Metamorphosis of the landlocked sea lamprey, Petromyzon marinus

    Science.gov (United States)

    Manion, Patrick J.; Stauffer, Thomas M.

    1970-01-01

    The external metamorphosis of the sea lamprey was divided into four stages, based primarily on the condition of the mouth: mouth reduced, mouth fused, mouth enclosed, and mouth elongated. During metamorphosis, the eye enlarged greatly, the snout and mouth region changed from a fleshy hood enclosing a sieve apparatus to a large sucking disc, the nasopore membrane and the branchial area shrank, the branchiopores changed in shape, the general color changed from dark brown and yellow to an intense blue-black dorsally and white ventrally, and the total length increased. Metamorphosis began in early to mid-July and did not take place after August. The duration of external metamorphosis was about 3 months for lampreys transforming under natural conditions. The mean lengths of metamorphosing lampreys from tributaries of lakes Superior and Michigan were 145 and 136 mm, respectively.

  1. The Concept of Metamorphosis and its Metaphors - Possible and Impossible Transformations of Life; Metamorphosis in Children's Literature

    Science.gov (United States)

    Bruguière, Catherine; Perru, Olivier; Charles, Frédéric

    2018-03-01

    The article examines a number of links between the metaphorical uses of the concept of metamorphosis in literature and the various changes of the meaning of the concept that took place at the beginning of the modern scientific age between the 17th and 19th centuries, a period during which the notion of metamorphosis resurfaced in conflict with evolutionist thinking. We present the extent to which the concept of animal metamorphosis, the object of multiple redefinitions over the course of this historical period, became the vector of a very strong metaphorical meaning, which emerged in the literature of the period and survives to this day in certain children's storybooks belonging to what we term the genre of "realistic fiction". We intend, from a pedagogical standpoint, to identify which specific attributes of these metaphors exist in those storybooks, and to gauge the extent to which those attributes contradict the scientific characteristics and fictional representations of the concept of metamorphosis.

  2. The Insect Neuropeptide PTTH Activates Receptor Tyrosine Kinase Torso to Initiate Metamorphosis

    DEFF Research Database (Denmark)

    Rewitz, Kim; Yamanaka, Naoki; Gilbert, Lawrence

    2009-01-01

    Holometabolous insects undergo complete metamorphosis to become sexually mature adults. Metamorphosis is initiated by brain-derived prothoracicotropic hormone (PTTH), which stimulates the production of the molting hormone ecdysone via an incompletely defined signaling pathway. Here we demonstrate...

  3. Career Pathways And Youth Metamorphosis Into Area Boys In ...

    African Journals Online (AJOL)

    Youth metamorphosis into area boys was found within structural forces including family disorganization, academic failure and poor career orientation. Unexpectedly, obedience to patron-client agencies ... Keywords: Deprivation, Social Mobility, Gangs, Deviance, Lagos African Journal for the Psychological Study of Social ...

  4. The Metamorphosis of Bourgeoisie Politics in a Modern Nigerian ...

    African Journals Online (AJOL)

    The Nigerian military class turned into Bourgeoisie class has credibility problems in the Nigerian state and politics. The paper interrogates their metamorphosis and masquerading character as ploy to delay the people-oriented revolution. The just-concluded PDP party primaries and secondary elections are evidence that ...

  5. Density-dependent growth and metamorphosis in the larval bronze ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 28; Issue 4. Density-dependent growth and metamorphosis in the larval bronze frog Rana temporalis is influenced by genetic relatedness of the cohort. S Girish S K Saidapur. Articles Volume 28 Issue 4 June 2003 pp 489-496 ...

  6. Density-dependent growth and metamorphosis in the larval bronze ...

    Indian Academy of Sciences (India)

    Unknown

    [Girish S and Saidapur S K 2002 Density-dependent growth and metamorphosis in the larval bronze frog Rana temporalis is influenced by genetic relatedness of the ... kin interaction during larval development in anurans seems to vary with the ... leaves were cut into small pieces of uniform size before boiling. Ten grams of ...

  7. Elemental concentration in mealworm beetle (Tenebrio molitor L.) during metamorphosis.

    Science.gov (United States)

    Simon, Edina; Baranyai, Edina; Braun, Mihály; Fábián, István; Tóthmérész, Béla

    2013-07-01

    Mealworm beetles have been used in numerous experiments as bioindicators. The aim of our experiment was to study the elemental composition in three larvae, pupae and first and second generation adult stages during their life cycle. We selected 180 larvae from a genetically similar population and put them in three groups, in two boxes (60 larvae in each box). Larvae were fed with mashed potato made of the same quality and quantity of potato powder. Then, we selected 10 individuals from each stage to the elemental analysis, using the ICP-OES method. The following elements were analysed in the studied stages: Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr and Zn. The results of principal component analysis demonstrated that based on elemental composition, different stages were separated with each other, but in the cases of the three larvae stages, high overlap was found. The results of the GLM ANOVA showed significant differences between the different stages of metamorphosis-based elemental composition. Our results show that the calcium and magnesium were found in a relatively high concentration, while the iron and zinc may be essential elements during the metamorphosis. Our results also show that in insect, the concentration of sodium was higher than in the pupa which may cause by hemolymph. We also demonstrated that the metamorphosis has an effect on the concentration of elements. Our study shows that in the different stages of insects, there are significant changes in the elemental composition of different stages of insects during their metamorphosis.

  8. The Mechanisms of the Ecdysone Pulses that Cause Metamorphosis

    DEFF Research Database (Denmark)

    Møller, Morten Erik

    of ecdysone biosynthesis, necessary for the generation of the temporally defined pulse prior to the metamorphosis. We found that ecdysone works back on the PG itself through its receptor, EcR, to regulate the expression of the transcription factor broad isoform Z4 (br-Z4), which in turn regulates...

  9. Troponin T isoform expression is modulated during Atlantic Halibut metamorphosis

    Directory of Open Access Journals (Sweden)

    Llewellyn Lynda

    2007-06-01

    Full Text Available Abstract Background Flatfish metamorphosis is a thyroid hormone (TH driven process which leads to a dramatic change from a symmetrical larva to an asymmetrical juvenile. The effect of THs on muscle and in particular muscle sarcomer protein genes is largely unexplored in fish. The change in Troponin T (TnT, a pivotal protein in the assembly of skeletal muscles sarcomeres and a modulator of calcium driven muscle contraction, during flatfish metamophosis is studied. Results In the present study five cDNAs for halibut TnT genes were cloned; three were splice variants arising from a single fast TnT (fTnT gene; a fourth encoded a novel teleost specific fTnT-like cDNA (AfTnT expressed exclusively in slow muscle and the fifth encoded the teleost specific sTnT2. THs modified the expression of halibut fTnT isoforms which changed from predominantly basic to acidic isoforms during natural and T4 induced metamorphosis. In contrast, expression of red muscle specific genes, AfTnT and sTnT2, did not change during natural metamorphosis or after T4 treatment. Prior to and after metamorphosis no change in the dorso-ventral symmetry or temporal-spatial expression pattern of TnT genes and muscle fibre organization occurred in halibut musculature. Conclusion Muscle organisation in halibut remains symmetrical even after metamorphosis suggesting TH driven changes are associated with molecular adaptations. We hypothesize that species specific differences in TnT gene expression in teleosts underlies different larval muscle developmental programs which better adapts them to the specific ecological constraints.

  10. Ouro proteins are not essential to tail regression during Xenopus tropicalis metamorphosis.

    Science.gov (United States)

    Nakai, Yuya; Nakajima, Keisuke; Robert, Jacques; Yaoita, Yoshio

    2016-03-01

    Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within 3 days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-knockout tadpoles expressed a very low level of mRNA transcribed from a targeted ouro gene, an undetectable level of Ouro protein encoded by a target gene and a scarcely detectable level of the other Ouro protein from the untargeted ouro gene in tail skin. Furthermore, congenital athymic frogs were produced by Foxn1 gene modification. Flow cytometry analysis showed that mutant frogs lacked splenic CD8(+) T cells, which play a major role in cytotoxic reaction. Furthermore, T-cell-dependent skin allograft rejection was dramatically impaired in mutant frogs. None of the knockout tadpoles showed any significant delay in the process of tail shortening during the climax of metamorphosis, which shows that Ouro proteins are not essential to tail regression at least in Xenopus tropicalis and argues against the immunological rejection model. © 2016 The Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  11. Macromolecular metamorphosis via stimulus-induced transformations of polymer architecture.

    Science.gov (United States)

    Sun, Hao; Kabb, Christopher P; Dai, Yuqiong; Hill, Megan R; Ghiviriga, Ion; Bapat, Abhijeet P; Sumerlin, Brent S

    2017-08-01

    Macromolecular architecture plays a pivotal role in determining the properties of polymers. When designing polymers for specific applications, it is not only the size of a macromolecule that must be considered, but also its shape. In most cases, the topology of a polymer is a static feature that is inalterable once synthesized. Using reversible-covalent chemistry to prompt the disconnection of chemical bonds and the formation of new linkages in situ, we report polymers that undergo dramatic topological transformations via a process we term macromolecular metamorphosis. Utilizing this technique, a linear amphiphilic block copolymer or hyperbranched polymer undergoes 'metamorphosis' into comb, star and hydrophobic block copolymer architectures. This approach was extended to include a macroscopic gel which transitioned from a densely and covalently crosslinked network to one with larger distances between the covalent crosslinks when heated. These architectural transformations present an entirely new approach to 'smart' materials.

  12. Macromolecular metamorphosis via stimulus-induced transformations of polymer architecture

    Science.gov (United States)

    Sun, Hao; Kabb, Christopher P.; Dai, Yuqiong; Hill, Megan R.; Ghiviriga, Ion; Bapat, Abhijeet P.; Sumerlin, Brent S.

    2017-08-01

    Macromolecular architecture plays a pivotal role in determining the properties of polymers. When designing polymers for specific applications, it is not only the size of a macromolecule that must be considered, but also its shape. In most cases, the topology of a polymer is a static feature that is inalterable once synthesized. Using reversible-covalent chemistry to prompt the disconnection of chemical bonds and the formation of new linkages in situ, we report polymers that undergo dramatic topological transformations via a process we term macromolecular metamorphosis. Utilizing this technique, a linear amphiphilic block copolymer or hyperbranched polymer undergoes 'metamorphosis' into comb, star and hydrophobic block copolymer architectures. This approach was extended to include a macroscopic gel which transitioned from a densely and covalently crosslinked network to one with larger distances between the covalent crosslinks when heated. These architectural transformations present an entirely new approach to 'smart' materials.

  13. Midgut morphological changes and autophagy during metamorphosis in sand flies.

    Science.gov (United States)

    Malta, Juliana; Heerman, Matthew; Weng, Ju Lin; Fernandes, Kenner M; Martins, Gustavo Ferreira; Ramalho-Ortigão, Marcelo

    2017-06-01

    During metamorphosis, holometabolous insects undergo significant remodeling of their midgut and become able to cope with changes in dietary requirements between larval and adult stages. At this stage, insects must be able to manage and recycle available food resources in order to develop fully into adults, especially when no nutrients are acquired from the environment. Autophagy has been previously suggested to play a crucial role during metamorphosis of the mosquito. Here, we investigate the overall morphological changes of the midgut of the sand fly during metamorphosis and assess the expression profiles of the autophagy-related genes ATG1, ATG6, and ATG8, which are associated with various steps of the autophagic process. Morphological changes in the midgut start during the fourth larval instar, with epithelial degeneration followed by remodeling via the differentiation of regenerative cells in pre-pupal and pupal stages. The changes in the midgut epithelium are paired with the up-regulation of ATG1, ATG6 and ATG8 during the larva-adult transition. Vein, a putative epidermal growth factor involved in regulating epithelial midgut regeneration, is also up-regulated. Autophagy has further been confirmed in sand flies via the presence of autophagosomes residing within the cytoplasmic compartment of the pupal stages. An understanding of the underlying mechanisms of this process should aid the future management of this neglected tropical vector.

  14. Human Development X: Explanation of Macroevolution — Top-Down Evolution Materializes Consciousness. The Origin of Metamorphosis

    Directory of Open Access Journals (Sweden)

    Tyge Dahl Hermansen

    2006-01-01

    Full Text Available In this paper, we first give a short discussion of the macroevolution viewing life as information-directed, complex, dynamic systems. On this basis, we give our explanation of the origin of life and discuss the top-down evolution of molecules, proteins, and macroevolution. We discuss these subjects according to our new holistic biological paradigm. In view of this, we discuss the macroevolution of the organism, the species, the biosphere, and human society. After this, we discuss the shift in evolution from natural selection to a new proposed process of nature called the “metamorphous top-down” evolution. We discuss the capability of the evolutionary shift to govern some of the processes that lead to the formation of new species. We discuss the mechanisms we think are behind this proposed shift in evolution and conclude that this event is able to explain the huge biological diversity of nature in combination with evolutionary natural selection. We also discuss this event of nature as an isolated, but integrated, part of the universe. We propose the most important genetic and biochemical process that we think is behind the evolutionary shift as a complicated symbiosis of mechanisms leading to metamorphosis in all biological individuals, from bacteria to humans. The energetic superorbital that manifests the consciousness governs all these processes through quantum chemical activity. This is the key to evolutionary shift through the consciousness, and we propose to call this process “adult human metamorphosis”.

  15. The thyroid gland and thyroid hormones in sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis.

    Science.gov (United States)

    Schnitzler, Joseph G; Klaren, Peter H M; Mariavelle, Emeline; Das, Krishna

    2016-04-01

    The sheepshead minnow is widely used in ecotoxicological studies that only recently have begun to focus on disruption of the thyroid axis by xenobiotics and endocrine disrupting compounds. However, reference levels of the thyroid prohormone thyroxine (T4) and biologically active hormone 3,5,3'-triiodothyronine (T3) and their developmental patterns are unknown. This study set out to describe the ontogeny and morphology of the thyroid gland in sheepshead minnow, and to correlate these with whole-body concentrations of thyroid hormones during early development and metamorphosis. Eggs were collected by natural spawning in our laboratory. T4 and T3 were extracted from embryos, larvae and juveniles and an enzyme-linked immunoassay was used to measure whole-body hormone levels. Length and body mass, hatching success, gross morphology, thyroid hormone levels and histology were measured. The onset of metamorphosis at 12-day post-hatching coincided with surges in whole-body T4 and T3 concentrations. Thyroid follicles were first observed in pre-metamorphic larvae at hatching and were detected exclusively in the subpharyngeal region, surrounding the ventral aorta. Follicle size and thyrocyte epithelial cell heights varied during development, indicating fluctuations in thyroid hormone synthesis activity. The increase in the whole-body T3/T4 ratio was indicative of an increase in outer ring deiodination activity. This study establishes a baseline for thyroid hormones in sheepshead minnows, which will be useful for the understanding of thyroid hormone functions and in future studies of thyroid toxicants in this species.

  16. Making REF is Making Politics: Memories of an Editorial Metamorphosis

    Directory of Open Access Journals (Sweden)

    Luzinete Simões Minella

    2008-01-01

    Full Text Available This article focuses on the new editorial model launched in Revista Estudos Feministas in 2002, that is, three years after its installation in Universidade Federal de Santa Catarina (UFSC. While firstly detailing the memories of such metamorphosis, the text refers to the transitions of REF’s editorship format, to the purposes and criteria of the new structure, as well as the meanings of the team expansion in relation to some national and international feminist publications. Eventually the article briefly discusses the advantages and challenges implicated in this new editorial policy.

  17. Induction of Metamorphosis of Larvae of the Green Sea Urchin, Strongylocentrotus droebachiensis, by Coralline Red Algae.

    Science.gov (United States)

    Pearce, C M; Scheibling, R E

    1990-12-01

    The coralline red algae, Lithothamnion glaciale, Phymatolithon laevigatum, P. rugulosum, and Corallina officinalis, induced >85% of laboratory-reared larvae of Strongylocentrotus droebachiensis to metamorphose. Larvae must contact live L. glaciale or its spores for metamorphosis to occur; the inducer is not sensed in the water column. However, aqueous extracts of L. glaciale can induce metamorphosis, suggesting that the inducing factor is chemical. Neither ashed nor boiled L. glaciale induces metamorphosis, indicating that the factor is heat-labile and that thigmotaxis, per se, is not important in the response. The amino-acid, γ-aminobutyric acid (GABA), which induces settlement of other marine invertebrate larvae, also induces significant rates of metamorphosis of S. droebachiensis at concentrations ≥ 10-4 M. A reduction (with antibiotics) in the number of live bacteria on the surface of L. glaciale does not affect the rate of metamorphosis of larvae.

  18. The reasons of metamorphosis and abundance of Kabylian vernacular houses

    Directory of Open Access Journals (Sweden)

    Walid Hamma

    2018-06-01

    Full Text Available Kabylia suffers from the abundance of its ancient villages and the metamorphosis of its traditional houses, which has led to a very advanced degradation and a loss of the authenticity of its old constructions. To understand the phenomenon of exodus, the reasons for its abundant villages and the remodeling of historical buildings, we adopted two approaches, the first is sociological through the use of questionnaire and the second is architectural through use of the method of morphological analysis. After survey, we first highlighted the reasons for the abundant which are economic at 74.89%, educational at 17.00%, social at 4.05%, political at 3.23% and religious at 0.83%. Then, the reasons for the metamorphosis of Kabyle houses, which are structural at 25.20%, functional at 31.70%, spatial at 34.95%, aesthetics at 4.06%, thermal insulation at 2.43% and sound insulation at 1.62%. Finally, the architectural parts changed are the structure at 69.10%, the materials at 13.01%, the roof at 98.37%, the facade at 39.02%, the decoration at 45.52%, the operation at 82.92%, the spaces at 85.63%, the area at 85.63% Thermal insulation at 13.82%, noise insulation at 7.31% and carpentry at 96.74%.

  19. Pigment Cell Progenitors in Zebrafish Remain Multipotent through Metamorphosis.

    Science.gov (United States)

    Singh, Ajeet Pratap; Dinwiddie, April; Mahalwar, Prateek; Schach, Ursula; Linker, Claudia; Irion, Uwe; Nüsslein-Volhard, Christiane

    2016-08-08

    The neural crest is a transient, multipotent embryonic cell population in vertebrates giving rise to diverse cell types in adults via intermediate progenitors. The in vivo cell-fate potential and lineage segregation of these postembryonic progenitors is poorly understood, and it is unknown if and when the progenitors become fate restricted. We investigate the fate restriction in the neural crest-derived stem cells and intermediate progenitors in zebrafish, which give rise to three distinct adult pigment cell types: melanophores, iridophores, and xanthophores. By inducing clones in sox10-expressing cells, we trace and quantitatively compare the pigment cell progenitors at four stages, from embryogenesis to metamorphosis. At all stages, a large fraction of the progenitors are multipotent. These multipotent progenitors have a high proliferation ability, which diminishes with fate restriction. We suggest that multipotency of the nerve-associated progenitors lasting into metamorphosis may have facilitated the evolution of adult-specific traits in vertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Proteomic analysis during larval development and metamorphosis of the spionid polychaete Pseudopolydora vexillosa

    KAUST Repository

    Mok, Flora SY

    2009-12-14

    Background: While the larval-juvenile transition (metamorphosis) in the spionid polychaete Pseudopolydora vexillosa involves gradual morphological changes and does not require substantial development of juvenile organs, the opposite occurs in the barnacle Balanus amphitrite. We hypothesized that the proteome changes during metamorphosis in the spionids are less drastic than that in the barnacles. To test this, proteomes of pre-competent larvae, competent larvae (ready to metamorphose), and juveniles of P. vexillosa were compared using 2-dimensional gel electrophoresis (2-DE), and they were then compared to those of the barnacle.Results: Unlike the significant changes found during barnacle metamorphosis, proteomes of competent P. vexillosa larvae were more similar to those of their juveniles. Pre-competent larvae had significantly fewer protein spots (384 spots), while both competent larvae and juveniles expressed about 660 protein spots each. Proteins up-regulated during competence identified by MALDI-TOF/TOF analysis included a molecular chaperon (calreticulin), a signal transduction regulator (tyrosin activation protein), and a tissue-remodeling enzyme (metallopeptidase).Conclusions: This was the first time to study the protein expression patterns during the metamorphosis of a marine polychaete and to compare the proteomes of marine invertebrates that have different levels of morphological changes during metamorphosis. The findings provide promising initial steps towards the development of a proteome database for marine invertebrate metamorphosis, thus deciphering the possible mechanisms underlying larval metamorphosis in non-model marine organisms. © 2009 Mok et al; licensee BioMed Central Ltd.

  1. Kafka's Writing Machine: Metamorphosis in the Penal Colony

    Directory of Open Access Journals (Sweden)

    Arnold Weinstein

    1982-09-01

    Full Text Available Kafka's "In the Penal Colony" is a problematic story, largely because of the conflicting interpretations it has received: does its famous machine dispense grace or torture? Is Kafka giving us a parable of Old vs. New Law? How does the "liberal" explorer or the "liberal" reader assess the Officer's impassioned pleading for the Machine and the kind of justice it serves? A strange kind of coherence emerges, however, when one focusses on the central unifying motif of the story: understanding. The tale itself is little more than the Officer's desperate effort to make the explorer-reader understand; the machine itself makes its victim understand the nature of justice. Language is, of course, a primary vehicle for understanding, and Kafka's story dramatizes two radically opposed languages: verbal and physical. All efforts to bridge the distance between people, between matter and spirit, seem to fail, at least insofar as spoken language is concerned; the machine's mission is to create physical language, an unmediated script which is the reality of which it speaks. By writing the crime onto and into the flesh of the criminal, the machine offers a sublime and frightening figure of "visceral knowledge," of the open self as the opened self. By entering into the machine himself, the Officer undergoes the classic Kafka metamorphosis: he becomes the prisoner, and he thereby suffers knowledge. The entire parable may be seen as an illustration of the writer's yearning for a language so potent that the reader would experience, "in the flesh," the writer's words. Kafka's own narrative techniques aim at precisely such a metamorphosis in the reader.

  2. Thyroid Histopathology Assessments for the Amphibian Metamorphosis Assay to Detect Thyroid-active Substances

    Science.gov (United States)

    In support of an Organization for Economic Cooperation and Development (OECD) Amphibian Metamorphosis Assay (AMA) Test Guideline for the detection of substances that interact with the hypothalamic-pituitary-thyroid axis, a document was developed that provides a standardized appro...

  3. Hindemith: Symphonic Metamorphosis on Themes of Carl Maria von Weber / Jonathan Swain

    Index Scriptorium Estoniae

    Swain, Jonathan

    1990-01-01

    Uuest heliplaadist "Hindemith: Symphonic Metamorphosis on Themes of Carl Maria von Weber, Mathis der Maler - Symphony, Nobilissima visione - suite. Atlanta Symphony Orchestra, Yoel Levi" Telarc/ Conifer CD 80 195

  4. Signatures of natural selection between life cycle stages separated by metamorphosis in European eel

    DEFF Research Database (Denmark)

    Pujolar, J.M.; Jacobsen, M.W.; Bekkevold, Dorte

    2015-01-01

    Species showing complex life cycles provide excellent opportunities to study the genetic associations between life cycle stages, as selective pressures may differ before and after metamorphosis. The European eel presents a complex life cycle with two metamorphoses, a first metamorphosis from larvae...... into glass eels (juvenile stage) and a second metamorphosis into silver eels (adult stage). We tested the hypothesis that different genes and gene pathways will be under selection at different life stages when comparing the genetic associations between glass eels and silver eels. Results: We used two sets...... supports the adaptive decoupling hypothesis for the benefits of metamorphosis. Partitioning the life cycle into discrete morphological phases may be overall beneficial since it allows the different life stages to respond independently to their unique selection pressures. This might translate into a more...

  5. Relevance of biofilm bacteria in modulating the larval metamorphosis of Balanus amphitrite

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Anil, A.C.; Raghukumar, S.

    that the water borne and the surface associated cues from the bacteria function differentially in mediating larval metamorphosis. Understanding the complexities involved in such interactions and identification of the factors governing them would be a step ahead....

  6. Increased Larval Density Induces Accelerated Metamorphosis Independently of Growth Rate in the FrogRana sphenocephala.

    Science.gov (United States)

    Richter, Janel; Martin, Lincoln; Beachy, Christopher K

    2009-01-01

    We grew larval Rana sphenocephala at different densities but maintained equal mean growth rates among density treatments (via equal per capita food levels) to test the hypothesis that larval density can influence metamorphic timing independently of larval growth rate. Tadpoles at high density metamorphosed earlier than tadpoles at low density despite growing at similar rates. Food reductions did not accelerate metamorphosis. These results support the hypothesis that density can be a sufficient cue to initiate metamorphosis independently of growth rate.

  7. The heterochronic gene Lin28 regulates amphibian metamorphosis through disturbance of thyroid hormone function.

    Science.gov (United States)

    Faunes, Fernando; Gundermann, Daniel G; Muñoz, Rosana; Bruno, Renzo; Larraín, Juan

    2017-05-15

    Metamorphosis is a classic example of developmental transition, which involves important morphological and physiological changes that prepare the organism for the adult life. It has been very well established that amphibian metamorphosis is mainly controlled by Thyroid Hormone (TH). Here, we show that the heterochronic gene Lin28 is downregulated during Xenopus laevis metamorphosis. Lin28 overexpression before activation of TH signaling delays metamorphosis and inhibits the expression of TH target genes. The delay in metamorphosis is rescued by incubation with exogenous TH, indicating that Lin28 works upstream or parallel to TH. High-throughput analyses performed before any delay on metamorphosis or change in TH signaling showed that overexpression of Lin28 reduces transcript levels of several hormones secreted by the pituitary, including the Thyroid-Stimulating Hormone (TSH), and regulates the expression of proteins involved in TH transport, metabolism and signaling, showing that Lin28 disrupts TH function at different levels. Our data demonstrates that the role of Lin28 in controlling developmental transitions is evolutionary conserved and establishes a functional interaction between Lin28 and thyroid hormone function introducing a new regulatory step in perinatal development with implications for our understanding of endocrine disorders. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Evolution of Ecdysis and Metamorphosis in Arthropods: The Rise of Regulation of Juvenile Hormone.

    Science.gov (United States)

    Cheong, Sam P S; Huang, Juan; Bendena, William G; Tobe, Stephen S; Hui, Jerome H L

    2015-11-01

    Arthropods are the most successful group of animals, and are found in diverse habitats; they account for more than 80% of described animal species. A rigid exoskeleton is a common feature that is shared across the different groups of arthropods. The exoskeleton offers protection and is shed between developmental stages via a unique evolutionarily conserved process known as molting/ecdysis. Molting is triggered by steroid hormones, the ecdysteroids, and the regulation of their biosynthesis has long been proposed as a contributor to the success of arthropods during evolution. Nevertheless, how novelties arose that contributed to the diversifications of arthropods remain unclear. Juvenile hormones (JHs) are sequiterpenoids that were thought to be unique to insects, modulating the timing of metamorphosis in conjunction with the actions of ecdysteroids. Here, we revisit the old question of "the role that the sesquiterpenoids play in arthropod evolution" with a focus on the neglected non-insect arthropods. We hypothesize that the sesquiterpenoid, methyl farnesoate (MF), had already established regulatory functions in the last common ancestor of arthropods, and the difference in the regulation of biosynthesis and degradation of sesquiterpenoids, such as MF and JH, was another major driving force in the successful radiation of insects. © The Author 2015. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

  9. Stress and serial adult metamorphosis: Multiple roles for the stress axis in socially regulated sex change

    Directory of Open Access Journals (Sweden)

    Tessa K Solomon-Lane

    2013-11-01

    Full Text Available Socially regulated sex change in teleost fishes is a striking example of social status information regulating biological function in the service of reproductive success. The establishment of social dominance in sex changing species is translated into a cascade of changes in behavior, physiology, neuroendocrine function, and morphology that transforms a female into a male, or vice versa. The hypothalamic-pituitary-interrenal axis (HPI, homologous to HP-adrenal axis in mammals and birds has been hypothesized to play a mechanistic role linking status to sex change. The HPA/I axis responds to environmental stressors by integrating relevant external and internal cues and coordinating biological responses including changes in behavior, energetics, physiology, and morphology (i.e., metamorphosis. Through actions of both corticotropin-releasing factor and glucocorticoids (GCs, the HPA/I axis has been implicated in processes central to sex change, including the regulation of agonistic behavior, social status, energetic investment, and life history transitions. In this paper, we review the hypothesized roles of the HPA/I axis in the regulation of sex change and how those hypotheses have been tested to date. We include original data on sex change in the bluebanded goby (Lythyrpnus dalli, a highly social fish capable of bidirectional sex change. We then propose a model for HPA/I involvement in sex change and discuss how these ideas might be tested in the future. Understanding the regulation of sex change has the potential to elucidate evolutionarily conserved mechanisms responsible for translating pertinent information about the environment into coordinated biological changes along multiple body axes.

  10. The Paradigm of Decline-Metamorphosis-Rebirth in Fine Arts

    Directory of Open Access Journals (Sweden)

    Tine Germ

    2015-12-01

    Full Text Available The triad of decline-metamorphosis-rebirth constantly reappears in the history of civilisation, it is current in all historical periods and cultural environments, in different areas and the most diverse contexts. Its manifestations are countless and the same is true of its interpretations. They are especially frequent in the area of art, because the evolutionary model, grounded in the idea of cyclic development comes very handy for explanations and illustrations which seek to present complicated things in a simple and clear way. The history of art, mainly in the 19th century, advocated a tripartite development of art which seeks greater perfection and maturity and reaches its peak just to be then inevitably followed by a decline in artistic originality and power. Already for some time now the evolutionary model has been shown too ineffective in addressing scholarly questions, especially due to oversimplification and a priori classification of subject matter which cannot possibly be classified. The perception that the art of the Early Renaissance was a preliminary period for more mature and accomplished achievements of High Renaissance which at some point began to lose its drive and went into decline either by repeating outmoded forms or their decomposition, is not only naive, but simply wrong and represents a misunderstanding of the essence of art. In much the same way it would be equally wrong to label in advance the early works of a certain artist as not-mature-yet or possessing less artistic authenticity.

  11. Glitches: The Exact Quantum Signatures of Pulsars Metamorphosis

    Science.gov (United States)

    Hujeirat, A. A.

    2018-03-01

    The observed recurrence of glitches in pulsars and neutron stars carries rich information about the evolution of their internal structures. In this article, I show that the glitch-events observed in pulsars are exact quantum signatures for their metamorphosis into dark super-baryons (SBs), whose interiors are made of purely incompressible superconducting gluon-quark superfluids. Here the quantum nuclear shell model is adopted to describe the permitted energy levels of the SB, which are assumed to be identical to the discrete spinning rates Ω_{SB} that SBs are allowed to rotate with. Accordingly, a glitch-event corresponds to a prompt spin-down of the superconducting SB from one energy level to the next, thereby expelling a certain number of vortices, which in turn spins up the ambient medium. The process is provoked mainly by the negative torque of the ambient dissipative nuclear fluid and by a universal scalar field φ at the background of a supranuclear dense matter. As dictated by the Onsager-Feynman equation, the prompt spin-down must be associated with increase of the dimensions of the embryonic SB to finally convert the entire pulsar into SB-Objects on the scale of Gyrs. Based on our calculations, a Vela-like pulsar should display billions of glitches during its lifetime, before it metamorphoses entirely into a maximally compact SB-object and disappears from our observational windows. The present model predicts the mass of SBs and ΔΩ/Ω in young pulsars to be relatively lower than their older counterparts

  12. Metamorphosis and neoteny: alternative pathways in an extinct amphibian clade.

    Science.gov (United States)

    Schoch, Rainer R; Fröbisch, Nadia B

    2006-07-01

    The Branchiosauridae was a clade of small amphibians from the Permo-Carboniferous with an overall salamander-like appearance. The clade is distinguished by an extraordinary fossil record that comprises hundreds of well-preserved specimens, representing a wide range of ontogenetic stages. Branchiosaurids had external gills and weakly ossified skeletons, and due to this larval appearance their status as neotenic (perennibranchiate) forms has long been accepted. Despite their extensive fossil record large specimens with an adult morphology appeared to be lacking altogether, but recently two adult specimens were identified in a rich sample of Apateon gracilis collected in the 19th century from a locality near Dresden, Saxony. These specimens are unique among branchiosaurids in showing a high level of ossification, including bones that have never been reported in a branchiosaur. These highlight the successive formation of features believed to indicate terrestrial locomotion, as well as feeding on larger prey items. Moreover, these transformations occurred in a small time window (whereas the degree of size increase is used as a proxy of time) and the degree of concentration of developmental events in branchiosaurids is unique among tetrapods outside the lissamphibians. These specimens are compared with large adults of the neotenic branchiosaurid Apateon caducus from the Saar-Nahe Basin, which despite their larger body size lack the features found in the adult A. gracilis specimens. These specimens give new insight into patterns of metamorphosis (morphological transformation) in branchiosaurids that are believed to be correlated to a change of habitat, and clearly show that different life-history pathways comparable to those of modern salamanders were already established in this Paleozoic clade.

  13. Do effects of mercury in larval amphibians persist after metamorphosis?

    Science.gov (United States)

    Todd, Brian D; Willson, John D; Bergeron, Christine M; Hopkins, William A

    2012-01-01

    Despite widespread concern about the role of environmental contaminants in global amphibian declines, and evidence that post-metamorphic life stages contribute disproportionately to amphibian population dynamics, most studies in amphibian ecotoxicology focus on larval life stages. Studies that focus solely on early life stages may miss important effects of contaminant exposure, such as latent effects that manifest some time after previous exposure. Moreover, it is often assumed that effects observed in amphibian larvae will persist to affect survival or reproduction later in life. We used terrestrial enclosures to determine whether exposure to mercury (Hg) through maternal transfer and/or larval diet had any adverse effects in post-metamorphic American toads (Bufo americanus). We found a 5% difference in size at metamorphosis that was attributed to maternal Hg exposure persisted for 1 year in the terrestrial environment, resulting in a 7% difference at the conclusion of the study. Although patterns of survival differed among treatments through time, we found no overall difference in survival after 1 year. We also found no evidence of emergent latent effects in the terrestrial toads that could be attributed to earlier exposure. Our results indicate that adverse effects of maternal Hg exposure that were observed in larval amphibians may persist to affect later terrestrial life stages but that no novel adverse effects developed when animals were raised in a semi-natural environment. Moreover, we found no evidence of persistent effects of dietary Hg exposure in larvae, highlighting a need for greater focus on maternal effects in amphibian ecotoxicology. Finally, we suggest an increase in the use of longitudinal studies to better understand contaminant impacts to amphibian populations via effects in both aquatic and terrestrial life stages.

  14. Biology

    Indian Academy of Sciences (India)

    I am particularly happy that the Academy is bringing out this document by Professor M S. Valiathan on Ayurvedic Biology. It is an effort to place before the scientific community, especially that of India, the unique scientific opportunities that arise out of viewing Ayurveda from the perspective of contemporary science, its tools ...

  15. The insect neuropeptide PTTH activates receptor tyrosine kinase torso to initiate metamorphosis.

    Science.gov (United States)

    Rewitz, Kim F; Yamanaka, Naoki; Gilbert, Lawrence I; O'Connor, Michael B

    2009-12-04

    Holometabolous insects undergo complete metamorphosis to become sexually mature adults. Metamorphosis is initiated by brain-derived prothoracicotropic hormone (PTTH), which stimulates the production of the molting hormone ecdysone via an incompletely defined signaling pathway. Here we demonstrate that Torso, a receptor tyrosine kinase that regulates embryonic terminal cell fate in Drosophila, is the PTTH receptor. Trunk, the embryonic Torso ligand, is related to PTTH, and ectopic expression of PTTH in the embryo partially rescues trunk mutants. In larvae, torso is expressed specifically in the prothoracic gland (PG), and its loss phenocopies the removal of PTTH. The activation of Torso by PTTH stimulates extracellular signal-regulated kinase (ERK) phosphorylation, and the loss of ERK in the PG phenocopies the loss of PTTH and Torso. We conclude that PTTH initiates metamorphosis by activation of the Torso/ERK pathway.

  16. [Modulating effect of weak combined magnetic fields on duration of mealworm beetle Tenebrio molitor metamorphosis stage].

    Science.gov (United States)

    Novikov, V V; Sheĭman, I M; Iablokova, E V; Fesenko, E E

    2014-01-01

    It is shown that an exposure of pupae of the mealworm beetle Tenebrio molitor to the combined static (42 μT) and very weak alternating (250 nT) magnetic fields exerts different influence, depending on the frequency of the alternating magnetic field, on duration of metamorphosis processes in these insects. For instance, an exposure of pupae to weak combined magnetic fields, adjusted to the frequency of ion cyclotron resonance for glutaminic acid (4,4 Hz), stimulates metamorphosis process--a transitional stage from pupae to imago lasts shorter. An inhibiting effect was observed when adjusted to the frequency of ion cyclotron resonance for Ca2 (32,2 Hz). At some frequencies this effect is not seen. For instance, an exposure at a frequency of ion cyclotron resonance for K+ (16,5 Hz) exerts no noticeable effect on the duration of the pupal metamorphosis stage.

  17. Cloning and stage-specific expression of CK-M1 gene during metamorphosis of Japanese flounder, Paralichthys olivaceus

    Science.gov (United States)

    Chen, Yanjie; Zhang, Quanqi; Qi, Jie; Wang, Zhigang; Wang, Xubo; Sun, Yeying; Zhong, Qiwang; Li, Shuo; Li, Chunmei

    2010-05-01

    The symmetrical body of flatfish larvae changes dramatically into an asymmetrical form after metamorphosis. The molecular mechanisms responsible for this change are poorly understood. As an initial step to clarify these mechanisms, we used representational difference analysis of cDNA for the identification of genes active during metamorphosis in the Japanese flounder, Paralichthys olicaceus. One of the up-regulated genes was identified as creatine kinase muscle type 1 (CK-M1). Sequence analysis of CK-M1 revealed that it spanned 1 708 bp and encoded a protein of 382 amino acids. The overall amino acid sequence of the CK-M1 was highly conserved with those of other organisms. CK-M1 was expressed in adult fish tissues, including skeletal muscle, intestine and gill. Whole mount in-situ hybridization showed that the enhanced expression of CK-M1 expanded from the head to the whole body of larvae as metamorphosis progressed. Quantitative analysis revealed stage-specific high expression of CK-M1 during metamorphosis. The expression level of CK-M1 increased initially and peaked at metamorphosis, decreased afterward, and finally returned to the pre-metamorphosis level. This stage-specific expression pattern suggested strongly that CK-M1 was related to metamorphosis in the Japanese flounder. Its specific role in metamorphosis requires further study.

  18. Structural and functional maturation of skin during metamorphosis in the Atlantic halibut (Hippoglossus hippoglossus)

    KAUST Repository

    Alves, Ricardo N.

    2018-02-20

    To establish if the developmental changes in the primary barrier and osmoregulatory capacity of Atlantic halibut skin are modified during metamorphosis, histological, histochemical, gene expression and electrophysiological measurements were made. The morphology of the ocular and abocular skin started to diverge during the metamorphic climax and ocular skin appeared thicker and more stratified. Neutral mucins were the main glycoproteins produced by the goblet cells in skin during metamorphosis. Moreover, the number of goblet cells producing neutral mucins increased during metamorphosis and asymmetry in their abundance was observed between ocular and abocular skin. The increase in goblet cell number and their asymmetric abundance in skin was concomitant with the period that thyroid hormones (THs) increase and suggests that they may be under the control of these hormones. Several mucin transcripts were identified in metamorphosing halibut transcriptomes and Muc18 and Muc5AC were characteristic of the body skin. Na+, K+-ATPase positive (NKA) cells were observed in skin of all metamorphic stages but their number significantly decreased with the onset of metamorphosis. No asymmetry was observed between ocular and abocular skin in NKA cells. The morphological changes observed were linked to modified skin barrier function as revealed by modifications in its electrophysiological properties. However, the maturation of the skin functional characteristics preceded structural maturation and occurred at stage 8 prior to the metamorphic climax. Treatment of Atlantic halibut with the THs disrupter methimazole (MMI) affected the number of goblet cells producing neutral mucins and the NKA cells. The present study reveals that the asymmetric development of the skin in Atlantic halibut is TH sensitive and is associated with metamorphosis and that this barrier’s functional properties mature earlier and are independent of metamorphosis.

  19. Precocious metamorphosis in the juvenile hormone-deficient mutant of the silkworm, Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Takaaki Daimon

    Full Text Available Insect molting and metamorphosis are intricately governed by two hormones, ecdysteroids and juvenile hormones (JHs. JHs prevent precocious metamorphosis and allow the larva to undergo multiple rounds of molting until it attains the proper size for metamorphosis. In the silkworm, Bombyx mori, several "moltinism" mutations have been identified that exhibit variations in the number of larval molts; however, none of them have been characterized molecularly. Here we report the identification and characterization of the gene responsible for the dimolting (mod mutant that undergoes precocious metamorphosis with fewer larval-larval molts. We show that the mod mutation results in complete loss of JHs in the larval hemolymph and that the mutant phenotype can be rescued by topical application of a JH analog. We performed positional cloning of mod and found a null mutation in the cytochrome P450 gene CYP15C1 in the mod allele. We also demonstrated that CYP15C1 is specifically expressed in the corpus allatum, an endocrine organ that synthesizes and secretes JHs. Furthermore, a biochemical experiment showed that CYP15C1 epoxidizes farnesoic acid to JH acid in a highly stereospecific manner. Precocious metamorphosis of mod larvae was rescued when the wild-type allele of CYP15C1 was expressed in transgenic mod larvae using the GAL4/UAS system. Our data therefore reveal that CYP15C1 is the gene responsible for the mod mutation and is essential for JH biosynthesis. Remarkably, precocious larval-pupal transition in mod larvae does not occur in the first or second instar, suggesting that authentic epoxidized JHs are not essential in very young larvae of B. mori. Our identification of a JH-deficient mutant in this model insect will lead to a greater understanding of the molecular basis of the hormonal control of development and metamorphosis.

  20. Triclosan exposure alters postembryonic development in a Pacific tree frog (Pseudacris regilla) Amphibian Metamorphosis Assay (TREEMA)

    International Nuclear Information System (INIS)

    Marlatt, Vicki L.; Veldhoen, Nik; Lo, Bonnie P.; Bakker, Dannika; Rehaume, Vicki; Vallée, Kurtis; Haberl, Maxine; Shang, Dayue; Aggelen, Graham C. van; Skirrow, Rachel C.; Elphick, James R.; Helbing, Caren C.

    2013-01-01

    The Amphibian Metamorphosis Assay (AMA), developed for Xenopus laevis, is designed to identify chemicals that disrupt thyroid hormone (TH)-mediated biological processes. We adapted the AMA for use on an ecologically-relevant North American species, the Pacific tree frog (Pseudacris regilla), and applied molecular endpoints to evaluate the effects of the antibacterial agent, triclosan (TCS). Premetamorphic (Gosner stage 26–28) tadpoles were immersed for 21 days in solvent control, 1.5 μg/L thyroxine (T 4 ), 0.3, 3 and 30 μg/L (nominal) TCS, or combined T 4 /TCS treatments. Exposure effects were scored by morphometric (developmental stage, wet weight, and body, snout-vent and hindlimb lengths) and molecular (mRNA abundance using quantitative real time polymerase chain reaction) criteria. T 4 treatment alone accelerated development concomitant with altered levels of TH receptors α and β, proliferating cell nuclear antigen, and gelatinase B mRNAs in the brain and tail. We observed TCS-induced perturbations in all of the molecular and morphological endpoints indicating that TCS exposure disrupts coordination of postembryonic tadpole development. Clear alterations in molecular endpoints were evident at day 2 whereas the earliest morphological effects appeared at day 4 and were most evident at day 21. Although TCS alone (3 and 30 μg/L) was protective against tadpole mortality, this protection was lost in the presence of T 4 . The Pacific tree frog is the most sensitive species examined to date displaying disruption of TH-mediated development by a common antimicrobial agent.

  1. Triclosan exposure alters postembryonic development in a Pacific tree frog (Pseudacris regilla) Amphibian Metamorphosis Assay (TREEMA)

    Energy Technology Data Exchange (ETDEWEB)

    Marlatt, Vicki L. [Nautilus Environmental, 8864 Commerce Court, Burnaby, B.C. V5A 4N7 (Canada); Veldhoen, Nik [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, B.C. V8W 3P6 (Canada); Lo, Bonnie P. [Nautilus Environmental, 8864 Commerce Court, Burnaby, B.C. V5A 4N7 (Canada); Bakker, Dannika; Rehaume, Vicki; Vallee, Kurtis [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, B.C. V8W 3P6 (Canada); Haberl, Maxine; Shang, Dayue; Aggelen, Graham C. van; Skirrow, Rachel C. [Pacific and Yukon Laboratory for Environmental Testing, Emergencies Operational Analytical Laboratories and Research Support Division, Environment Canada, 2645 Dollarton Highway, North Vancouver, B.C. V7H 1B1 (Canada); Elphick, James R. [Nautilus Environmental, 8864 Commerce Court, Burnaby, B.C. V5A 4N7 (Canada); Helbing, Caren C., E-mail: chelbing@uvic.ca [Department of Biochemistry and Microbiology, University of Victoria, P.O. Box 3055 Stn CSC, Victoria, B.C. V8W 3P6 (Canada)

    2013-01-15

    The Amphibian Metamorphosis Assay (AMA), developed for Xenopus laevis, is designed to identify chemicals that disrupt thyroid hormone (TH)-mediated biological processes. We adapted the AMA for use on an ecologically-relevant North American species, the Pacific tree frog (Pseudacris regilla), and applied molecular endpoints to evaluate the effects of the antibacterial agent, triclosan (TCS). Premetamorphic (Gosner stage 26-28) tadpoles were immersed for 21 days in solvent control, 1.5 {mu}g/L thyroxine (T{sub 4}), 0.3, 3 and 30 {mu}g/L (nominal) TCS, or combined T{sub 4}/TCS treatments. Exposure effects were scored by morphometric (developmental stage, wet weight, and body, snout-vent and hindlimb lengths) and molecular (mRNA abundance using quantitative real time polymerase chain reaction) criteria. T{sub 4} treatment alone accelerated development concomitant with altered levels of TH receptors {alpha} and {beta}, proliferating cell nuclear antigen, and gelatinase B mRNAs in the brain and tail. We observed TCS-induced perturbations in all of the molecular and morphological endpoints indicating that TCS exposure disrupts coordination of postembryonic tadpole development. Clear alterations in molecular endpoints were evident at day 2 whereas the earliest morphological effects appeared at day 4 and were most evident at day 21. Although TCS alone (3 and 30 {mu}g/L) was protective against tadpole mortality, this protection was lost in the presence of T{sub 4}. The Pacific tree frog is the most sensitive species examined to date displaying disruption of TH-mediated development by a common antimicrobial agent.

  2. Delayed metamorphosis and recurrence of bacterial infection in irradiated Rana clamitans tadpoles

    International Nuclear Information System (INIS)

    Hart, D.R.

    1982-03-01

    X-ray doses of 5 and 10 Gy (1 Gy/min) given to premetamorphic Green Frog (Rana clamitans) tadpoles delayed their metamorphosis relative to unirradiated controls. Previous pathogenic bacterial infections recurred in irradiated animals prior to metamorphic climax. Limited mortality occurred during metamorphic climax, 80-105 days after irradiation

  3. Quantitative proteomics identify molecular targets that are crucial in larval settlement and metamorphosis of bugula neritina

    KAUST Repository

    Zhang, Huoming

    2011-01-07

    The marine invertebrate Bugula neritina has a biphasic life cycle that consists of a swimming larval stage and a sessile juvenile and adult stage. The attachment of larvae to the substratum and their subsequent metamorphosis have crucial ecological consequences. Despite many studies on this species, little is known about the molecular mechanism of these processes. Here, we report a comparative study of swimming larvae and metamorphosing individuals at 4 and 24 h postattachment using label-free quantitative proteomics. We identified more than 1100 proteins at each stage, 61 of which were differentially expressed. Specifically, proteins involved in energy metabolism and structural molecules were generally down-regulated, whereas proteins involved in transcription and translation, the extracellular matrix, and calcification were strongly up-regulated during metamorphosis. Many tightly regulated novel proteins were also identified. Subsequent analysis of the temporal and spatial expressions of some of the proteins and an assay of their functions indicated that they may have key roles in metamorphosis of B. neritina. These findings not only provide molecular evidence with which to elucidate the substantial changes in morphology and physiology that occur during larval attachment and metamorphosis but also identify potential targets for antifouling treatment. © 2011 American Chemical Society.

  4. Characterization and expression of calmodulin gene during larval settlement and metamorphosis of the polychaete Hydroides elegans

    KAUST Repository

    Chen, Zhangfan

    2012-08-01

    The polychaete . Hydroides elegans (Serpulidae, Lophotrochozoa) is a problematic marine fouling organism in most tropical and subtropical coastal environment. Competent larvae of . H. elegans undergo the transition from the swimming larval stage to the sessile juvenile stage with substantial morphological, physiological, and behavior changes. This transition is often referred to as larval settlement and metamorphosis. In this study, we examined the possible involvement of calmodulin (CaM) - a multifunctional calcium metabolism regulator, in the larval settlement and metamorphosis of . H. elegans. A full-length . CaM cDNA was successfully cloned from . H. elegans (. He-CaM) and it contained an open reading frame of 450. bp, encoding 149 amino acid residues. It was highly expressed in 12. h post-metamorphic juveniles, and remained high in adults. . In situ hybridization conducted in competent larvae and juveniles revealed that . He-CaM gene was continuously expressed in the putative growth zones, branchial rudiments, and collar region, suggesting that . He-CaM might be involved in tissue differentiation and development. Our subsequent bioassay revealed that the CaM inhibitor W7 could effectively inhibit larval settlement and metamorphosis, and cause some morphological defects of unsettled larvae. In conclusion, our results revealed that CaM has important functions in the larval settlement and metamorphosis of . H. elegans. © 2012 Elsevier Inc..

  5. Control of Pituitary Thyroid-stimulating Hormone Synthesis and Secretion by Thyroid Hormones during Xenopus Metamorphosis

    Science.gov (United States)

    Serum thyroid hormone (TH) concentrations in anuran larvae rise rapidly during metamorphosis. Such a rise in an adult anuran would inevitably trigger a negative feedback response resulting in decreased synthesis and secretion of thyroid-stimulating hormone (TSH) by the pituitary....

  6. A phosphoproteomics approach to elucidate neuropeptide signal transduction controlling insect metamorphosis

    DEFF Research Database (Denmark)

    Rewitz, Kim F; Larsen, Martin R; Lobner-Olesen, Anders

    2009-01-01

    In insects, the neuropeptide prothoracicotropic hormone (PTTH) stimulates production of ecdysone (E) in the prothoracic glands (PGs). E is the precursor of the principal steroid hormone, 20-hydroxyecdysone (20E), that is responsible for eliciting molting and metamorphosis. In this study, we used ...

  7. Stable isotope enrichment in laboratory ant colonies: effects of colony age, metamorphosis, diet, and fat storage

    Science.gov (United States)

    Ecologists use stable isotopes to infer diets and trophic levels of animals in food webs, yet some assumptions underlying these inferences have not been thoroughly tested. We used laboratory-reared colonies of Solenopsis invicta Buren (Formicidae: Solenopsidini) to test the effects of metamorphosis,...

  8. Exploration and metamorphosis in Balanus amphitrite Darwin (Cirripedia ; Thoracica) cyprids: significance of sugars and adult extract

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Anil, A; Raghukumar, S.

    metamorphosis than the non-treated cyprids at 10-8M, whereas cyprids treated with the other LCA specific sugar (D-glucose) showed an inhibitory effect in the absence of AE. This result implies the involvement of D-mannose moieties of AE in the settlement...

  9. Influence of bacterial exopolymers, conspecific adult extract and salinity on the cyprid metamorphosis of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Anil, A.C.; Khandeparker, R.

    The influence of bacterial exopolymers and conspecific adult extract of Balanus amphitrite on metamorphosis of cyprid larvae at different salinities has been evaluated through laboratory assay. The bacterial exopolymers (epm) extracted from...

  10. Using bacterial extract along with differential gene expression in Acropora millepora larvae to decouple the processes of attachment and metamorphosis.

    Directory of Open Access Journals (Sweden)

    Nachshon Siboni

    Full Text Available Biofilms of the bacterium Pseudoalteromonas induce metamorphosis of acroporid coral larvae. The bacterial metabolite tetrabromopyrrole (TBP, isolated from an extract of Pseudoalteromonas sp. associated with the crustose coralline alga (CCA Neogoniolithon fosliei, induced coral larval metamorphosis (100% with little or no attachment (0-2%. To better understand the molecular events and mechanisms underpinning the induction of Acropora millepora larval metamorphosis, including cell proliferation, apoptosis, differentiation, migration, adhesion and biomineralisation, two novel coral gene expression assays were implemented. These involved the use of reverse-transcriptase quantitative PCR (RT-qPCR and employed 47 genes of interest (GOI, selected based on putative roles in the processes of settlement and metamorphosis. Substantial differences in transcriptomic responses of GOI were detected following incubation of A. millepora larvae with a threshold concentration and 10-fold elevated concentration of TBP-containing extracts of Pseudoalteromonas sp. The notable and relatively abrupt changes of the larval body structure during metamorphosis correlated, at the molecular level, with significant differences (p<0.05 in gene expression profiles of 24 GOI, 12 hours post exposure. Fourteen of those GOI also presented differences in expression (p<0.05 following exposure to the threshold concentration of bacterial TBP-containing extract. The specificity of the bacterial TBP-containing extract to induce the metamorphic stage in A. millepora larvae without attachment, using a robust, low cost, accurate, ecologically relevant and highly reproducible RT-qPCR assay, allowed partially decoupling of the transcriptomic processes of attachment and metamorphosis. The bacterial TBP-containing extract provided a unique opportunity to monitor the regulation of genes exclusively involved in the process of metamorphosis, contrasting previous gene expression studies that

  11. Dependency on de novo protein synthesis and proteomic changes during metamorphosis of the marine bryozoan Bugula neritina

    KAUST Repository

    Wong, Yue Him

    2010-05-24

    Background: Metamorphosis in the bryozoan Bugula neritina (Linne) includes an initial phase of rapid morphological rearrangement followed by a gradual phase of morphogenesis. We hypothesized that the first phase may be independent of de novo synthesis of proteins and, instead, involves post-translational modifications of existing proteins, providing a simple mechanism to quickly initiate metamorphosis. To test our hypothesis, we challenged B. neritina larvae with transcription and translation inhibitors. Furthermore, we employed 2D gel electrophoresis to characterize changes in the phosphoproteome and proteome during early metamorphosis. Differentially expressed proteins were identified by liquid chromatography tandem mass spectrometry and their gene expression patterns were profiled using semi-quantitative real time PCR.Results: When larvae were incubated with transcription and translation inhibitors, metamorphosis initiated through the first phase but did not complete. We found a significant down-regulation of 60 protein spots and the percentage of phosphoprotein spots decreased from 15% in the larval stage to12% during early metamorphosis. Two proteins--the mitochondrial processing peptidase beta subunit and severin--were abundantly expressed and phosphorylated in the larval stage, but down-regulated during metamorphosis. MPPbeta and severin were also down-regulated on the gene expression level.Conclusions: The initial morphogenetic changes that led to attachment of B. neritina did not depend on de novo protein synthesis, but the subsequent gradual morphogenesis did. This is the first time that the mitochondrial processing peptidase beta subunit or severin have been shown to be down-regulated on both gene and protein expression levels during the metamorphosis of B. neritina. Future studies employing immunohistochemistry to reveal the expression locality of these two proteins during metamorphosis should provide further evidence of the involvement of these two

  12. Are the anticipatory pathways in lecithotrophic larvae that delay metamorphosis adaptations? (A review).

    Science.gov (United States)

    Freeman, Gary

    2012-01-01

    During anticipatory development in lecithotrophic larvae that delay metamorphosis, the growth and differentiation of features of the adult action system continue to develop at a slow pace even though they do not become functional. After metamorphosis occurs, the larger size and advanced development of these components may allow juveniles to initially grow at a faster rate than they normally would. Anticipatory development has been demonstrated in archeogastropods, some solitary ascidians and a hydrozoan. In the gastropod Haliotis and the hydrozoan Phialidium anticipatory development increases the initial growth rate of juveniles. In Haliotis and ascidians all of the larvae of a given female that live long enough exhibit anticipatory development. In Phialidium, the ability of a given female to produce larvae that can exhibit anticipatory development is a maternal polymorphic character. In Haliotis and solitary ascidians that exhibit anticipatory development, it appears to be a slower version of the rapid developmental changes that occur in parts of the adult action system at metamorphosis. In Phialidium, developmental changes in relative sizes of the different presumptive regions of the polyp are slowly altered prior to and independently of metamorphosis. Anticipatory development is not linked to the decrease in the size or nutrient reserves of older larvae but to the length of their larval period. From an evolutionary perspective, the mechanisms that operate during anticipatory development are probably of adaptive significance for lecithotrophic larvae of species that spend variable amounts of time in the water column because of a patchy distribution of appropriate settlement cues. The developmental mechanisms that underlie anticipatory development may have been used during the transition from lecithotrophy to planktotrophy. © 2012 Wiley Periodicals, Inc.

  13. Control of target gene specificity during metamorphosis by the steroid response gene E93

    OpenAIRE

    Mou, Xiaochun; Duncan, Dianne M.; Baehrecke, Eric H.; Duncan, Ian

    2012-01-01

    Hormonal control of sexual maturation is a common feature in animal development. A particularly dramatic example is the metamorphosis of insects, in which pulses of the steroid hormone ecdysone drive the wholesale transformation of the larva into an adult. The mechanisms responsible for this transformation are not well understood. Work in Drosophila indicates that the larval and adult forms are patterned by the same underlying sets of developmental regulators, but it is not understood how the...

  14. Ouro proteins are not essential to tail regression during Xenopus tropicalis metamorphosis

    OpenAIRE

    Nakai, Yuya; Nakajima, Keisuke; Robert, Jacques; Yaoita, Yoshio

    2016-01-01

    Tail regression is one of the most prominent transformations observed during anuran metamorphosis. A tadpole tail that is twice as long as the tadpole trunk nearly disappears within three days in Xenopus tropicalis. Several years ago, it was proposed that this phenomenon is driven by an immunological rejection of larval-skin-specific antigens, Ouro proteins. We generated ouro-knockout tadpoles using the TALEN method to reexamine this immunological rejection model. Both the ouro1- and ouro2-kn...

  15. Organocatalytic Stereoconvergent Synthesis of α-CF3Amides: Triketopiperazines and Their Heterocyclic Metamorphosis.

    Science.gov (United States)

    Foster, Robert W; Lenz, Eva N; Simpkins, Nigel S; Stead, Darren

    2017-07-03

    The highly enantioselective alkylation of α-CF 3 enolates, generated from triketopiperazines, has been accomplished through use of a bifunctional thiourea organocatalyst to facilitate 1,4-addition to varied enone acceptors. On treatment with appropriate nitrogen nucleophiles, the chiral triketopiperazine products undergo a metamorphosis, to provide novel fused heterocyclic lactams such as extended pyrazolopyrimidines. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Signatures of natural selection between life cycle stages separated by metamorphosis in European eel.

    Science.gov (United States)

    Pujolar, J M; Jacobsen, M W; Bekkevold, D; Lobón-Cervià, J; Jónsson, B; Bernatchez, L; Hansen, M M

    2015-08-13

    Species showing complex life cycles provide excellent opportunities to study the genetic associations between life cycle stages, as selective pressures may differ before and after metamorphosis. The European eel presents a complex life cycle with two metamorphoses, a first metamorphosis from larvae into glass eels (juvenile stage) and a second metamorphosis into silver eels (adult stage). We tested the hypothesis that different genes and gene pathways will be under selection at different life stages when comparing the genetic associations between glass eels and silver eels. We used two sets of markers to test for selection: first, we genotyped individuals using a panel of 80 coding-gene single nucleotide polymorphisms (SNPs) developed in American eel; second, we investigated selection at the genome level using a total of 153,423 RAD-sequencing generated SNPs widely distributed across the genome. Using the RAD approach, outlier tests identified a total of 2413 (1.57%) potentially selected SNPs. Functional annotation analysis identified signal transduction pathways as the most over-represented group of genes, including MAPK/Erk signalling, calcium signalling and GnRH (gonadotropin-releasing hormone) signalling. Many of the over-represented pathways were related to growth, while others could result from the different conditions that eels inhabit during their life cycle. The observation of different genes and gene pathways under selection when comparing glass eels vs. silver eels supports the adaptive decoupling hypothesis for the benefits of metamorphosis. Partitioning the life cycle into discrete morphological phases may be overall beneficial since it allows the different life stages to respond independently to their unique selection pressures. This might translate into a more effective use of food and niche resources and/or performance of phase-specific tasks (e.g. feeding in the case of glass eels, migrating and reproducing in the case of silver eels).

  17. Larval development and metamorphosis of the deep-sea cidaroid urchin Cidaris blakei.

    Science.gov (United States)

    Bennett, Kathleen C; Young, Craig M; Emlet, Richard B

    2012-04-01

    Cidaroids, one of the two major sister clades of sea urchins, first appeared during the lower Permian (ca. 270 mya) and are considered to represent the primitive form of all living echinoids. This study of Cidaris blakei, a deep-sea cidaroid urchin with planktotrophic larvae, provides a description of development from fertilization through early juvenile stages and is the first report of a deep-sea urchin reared through metamorphosis. C. blakei resembles other cidaroids in its lack of a cohesive hyaline layer, the absence of an amniotic invagination for juvenile rudiment formation, and the presence of spines with a single morphotype at metamorphosis. C. blakei differed from other cidaroids in the presence of an apical tuft, the extent of fenestration of postoral skeletal rods, the shape of juvenile spines, and an extended (14-day) lecithotrophic stage prior to development of a complete gut. The development of C. blakei, 120 days from fertilization to metamorphosis, was protracted relative to that of shallow-water cidaroids. Preliminary work on temperature tolerances suggests that C. blakei larvae would be unable to survive the warmer temperatures higher in the water column and are therefore unable to vertically migrate.

  18. Differential expression of proteins and phosphoproteins during larval metamorphosis of the polychaete Capitella sp. I

    Directory of Open Access Journals (Sweden)

    Qian Pei-Yuan

    2011-09-01

    Full Text Available Abstract Background The spontaneous metamorphosis of the polychaete Capitella sp. I larvae into juveniles requires minor morphological changes, including segment formation, body elongation, and loss of cilia. In this study, we investigated changes in the expression patterns of both proteins and phosphoproteins during the transition from larvae to juveniles in this species. We used two-dimensional gel electrophoresis (2-DE followed by multiplex fluorescent staining and MALDI-TOF mass spectrometry analysis to identify the differentially expressed proteins as well as the protein and phosphoprotein profiles of both competent larvae and juveniles. Results Twenty-three differentially expressed proteins were identified in the two developmental stages. Expression patterns of two of those proteins were examined at the protein level by Western blot analysis while seven were further studied at the mRNA level by real-time PCR. Results showed that proteins related to cell division, cell migration, energy storage and oxidative stress were plentifully expressed in the competent larvae; in contrast, proteins involved in oxidative metabolism and transcriptional regulation were abundantly expressed in the juveniles. Conclusion It is likely that these differentially expressed proteins are involved in regulating the larval metamorphosis process and can be used as protein markers for studying molecular mechanisms associated with larval metamorphosis in polychaetes.

  19. The uptake of 14C-glycine to Bufo vulgaris formosus (Boulenger) larva at metamorphosis

    International Nuclear Information System (INIS)

    Hasegawa, Hitoshi; Tanaka, Haruo; Ishiguro, Shigeru; Nonoyama, Kiyoshi; Nakagawa, Harumi.

    1981-01-01

    With the eggs of Bufo vulgaris formosus (Boulenger) immediately after fertilization, the larvae in the 50 ml solution containing 1 ml of 14 C-glycine were developed to the end of metamorphosis. Measurements were made on the length of body, tail, fore limb and hind leg through the stages of tail degeneration and vestige. The radioactivity of the cut off fore limbs, hind legs, tails and head trunks was measured with a scintillation counter, and the 10 μ sections of the samples were used for autoradiography. The larvae uptook orally 14 C-glycine to the organs of cell tissues. On the basis of the reports of the autolysis of tails and the activation of lysosome enzyme in metamorphosis and on the uptake of 14 C-leucine and 14 C-proline to four legs by other workers, and on the present results, the free amino acids formed from the autolysis of tails were utilized for the recomposition of organ protein synthesis in the metamorphosis of the amphibians. (J.P.N.)

  20. The Metamorphosis of the Victim of Crime: From Crime to Culture and the Implications for Justice

    Directory of Open Access Journals (Sweden)

    Sandra Walklate

    2016-12-01

    Full Text Available Beck (2015: 81 observes, metamorphosis ‘is proceeding latently, behind the mind walls of unintended side effects, which are being constructed as ‘natural’ and ‘self-evident’. Thus Beck’s concept of metamorphosis conceives of social change as unnoticed and unacknowledged. Such change is evident in the contemporary ever present invocation of the ‘victim’ in a wide range of different, crime-soaked circumstances. This paper is concerned to explore this metamorphosis of the ‘victim’ in reflecting on two narratives: the victim narrative and the trauma narrative. The contemporary conflation of these two narratives has led Agamben (1999: 13 to suggest that policy has proceeded as if ‘“testis” (the testimony of a person as a third party in a trial or a law suit can be conflated with “superstes” (a person who has lived through something and can thereby bear witness to it’. The paper makes the case that this conflation has consequences for understandings of justice.

  1. Effects of depleted uranium on survival, growth, and metamorphosis in the african clawed frog (Xenopus laevis)

    Science.gov (United States)

    Mitchell, S.E.; Caldwell, C.A.; Gonzales, G.; Gould, W.R.; Arimoto, R.

    2005-01-01

    Embryos (stage 8-47, Nieuwkoop and Faber) of the African clawed frog (Xenopus laevis) were subjected to water-borne depleted uranium (DU) concentrations that ranged from 4.8 to 77.7 mg/Lusing an acute 96-h frog embryo teratogenesis assay-Xenopus (FETAX). In a chronic 64-d assay, X. laevis (from embryo through metamorphosis; stages 8-66) were subjected to concentrations of DU that ranged from 6.2 to 54.3 mg/L Our results indicate DU is a non teratogenic metal. No effects on mortality, malformations, or growth were observed in the 96-h FETAX with concentrations of DU that ranged from 4.8 to 77.7 mg/L From stage 8 to stage 47, X. laevis tadpoles do not actively feed and the gills are not well developed. Thus, uptake of DU was reduced despite exposure to elevated concentrations. The 64-d assay resulted in no concentration response for either mortality or malformations; however, a delay in metamorphosis was observed in tadpoles subjected to elevated DU concentrations (from 13.1 to 54.3 mg/L) compared to tadpoles in both the well-water control and reference. The delay in metamorphosis was likely due to increasing body burden of DU that ranged from 0.98 to 2.82 mg/kg. Copyright?? Taylor & Francis Inc.

  2. Differential expression of proteins and phosphoproteins during larval metamorphosis of the polychaete Capitella sp. I

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2011-09-03

    Background: The spontaneous metamorphosis of the polychaete Capitella sp. I larvae into juveniles requires minor morphological changes, including segment formation, body elongation, and loss of cilia. In this study, we investigated changes in the expression patterns of both proteins and phosphoproteins during the transition from larvae to juveniles in this species. We used two-dimensional gel electrophoresis (2-DE) followed by multiplex fluorescent staining and MALDI-TOF mass spectrometry analysis to identify the differentially expressed proteins as well as the protein and phosphoprotein profiles of both competent larvae and juveniles.Results: Twenty-three differentially expressed proteins were identified in the two developmental stages. Expression patterns of two of those proteins were examined at the protein level by Western blot analysis while seven were further studied at the mRNA level by real-time PCR. Results showed that proteins related to cell division, cell migration, energy storage and oxidative stress were plentifully expressed in the competent larvae; in contrast, proteins involved in oxidative metabolism and transcriptional regulation were abundantly expressed in the juveniles.Conclusion: It is likely that these differentially expressed proteins are involved in regulating the larval metamorphosis process and can be used as protein markers for studying molecular mechanisms associated with larval metamorphosis in polychaetes. © 2011 Chandramouli et al; licensee BioMed Central Ltd.

  3. Involvement of wnt signaling pathways in the metamorphosis of the bryozoan bugula neritina

    KAUST Repository

    Wong, Yue Him

    2012-03-20

    In this study, we analyzed the metamorphosis of the marine bryozoan Bugula neritina. We observed the morphogenesis of the ancestrula. We defined three distinct pre-ancestrula stages based on the anatomy of the developing polypide and the overall morphology of pre-ancestrula. We then used an annotation based enrichment analysis tool to analyze the B. neritina transcriptome and identified over-representation of genes related to Wnt signaling pathways, suggesting its involvement in metamorphosis. Finally, we studied the temporal-spatial gene expression studies of several Wnt pathway genes. We found that one of the Wnt ligand, BnWnt10, was expressed spatially opposite to the Wnt antagonist BnsFRP within the blastemas, which is the presumptive polypide. Down-stream components of the canonical Wnt signaling pathway were exclusively expressed in the blastemas. Bn?catenin and BnFz5/8 were exclusively expressed in the blastemas throughout the metamorphosis. Based on the genes expression patterns, we propose that BnWnt10 and BnsFRP may relate to the patterning of the polypide, in which the two genes served as positional signals and contributed to the polarization of the blastemas. Another Wnt ligand, BnWnt6, was expressed in the apical part of the pre-ancestrula epidermis. Overall, our findings suggest that the Wnt signaling pathway may be important to the pattern formation of polypide and the development of epidermis. © 2012 Wong et al.

  4. FMAj: a tool for high content analysis of muscle dynamics in Drosophila metamorphosis

    Science.gov (United States)

    2014-01-01

    Background During metamorphosis in Drosophila melanogaster, larval muscles undergo two different developmental fates; one population is removed by cell death, while the other persistent subset undergoes morphological remodeling and survives to adulthood. Thanks to the ability to perform live imaging of muscle development in transparent pupae and the power of genetics, metamorphosis in Drosophila can be used as a model to study the regulation of skeletal muscle mass. However, time-lapse microscopy generates sizeable image data that require new tools for high throughput image analysis. Results We performed targeted gene perturbation in muscles and acquired 3D time-series images of muscles in metamorphosis using laser scanning confocal microscopy. To quantify the phenotypic effects of gene perturbations, we designed the Fly Muscle Analysis tool (FMAj) which is based on the ImageJ and MySQL frameworks for image processing and data storage, respectively. The image analysis pipeline of FMAj contains three modules. The first module assists in adding annotations to time-lapse datasets, such as genotypes, experimental parameters and temporal reference points, which are used to compare different datasets. The second module performs segmentation and feature extraction of muscle cells and nuclei. Users can provide annotations to the detected objects, such as muscle identities and anatomical information. The third module performs comparative quantitative analysis of muscle phenotypes. We applied our tool to the phenotypic characterization of two atrophy related genes that were silenced by RNA interference. Reduction of Drosophila Tor (Target of Rapamycin) expression resulted in enhanced atrophy compared to control, while inhibition of the autophagy factor Atg9 caused suppression of atrophy and enlarged muscle fibers of abnormal morphology. FMAj enabled us to monitor the progression of atrophic and hypertrophic phenotypes of individual muscles throughout metamorphosis

  5. Control of target gene specificity during metamorphosis by the steroid response gene E93

    Science.gov (United States)

    Mou, Xiaochun; Duncan, Dianne M.; Baehrecke, Eric H.; Duncan, Ian

    2012-01-01

    Hormonal control of sexual maturation is a common feature in animal development. A particularly dramatic example is the metamorphosis of insects, in which pulses of the steroid hormone ecdysone drive the wholesale transformation of the larva into an adult. The mechanisms responsible for this transformation are not well understood. Work in Drosophila indicates that the larval and adult forms are patterned by the same underlying sets of developmental regulators, but it is not understood how the same regulators pattern two distinct forms. Recent studies indicate that this ability is facilitated by a global change in the responsiveness of target genes during metamorphosis. Here we show that this shift is controlled in part by the ecdysone-induced transcription factor E93. Although long considered a dedicated regulator of larval cell death, we find that E93 is expressed widely in adult cells at the pupal stage and is required for many patterning processes at this time. To understand the role of E93 in adult patterning, we focused on a simple E93-dependent process, the induction of the Dll gene within bract cells of the pupal leg by EGF receptor signaling. In this system, we show that E93 functions to cause Dll to become responsive to EGF receptor signaling. We demonstrate that E93 is both necessary and sufficient for directing this switch. E93 likely controls the responsiveness of many other target genes because it is required broadly for patterning during metamorphosis. The wide conservation of E93 orthologs suggests that similar mechanisms control life-cycle transitions in other organisms, including vertebrates. PMID:22308414

  6. Control of target gene specificity during metamorphosis by the steroid response gene E93.

    Science.gov (United States)

    Mou, Xiaochun; Duncan, Dianne M; Baehrecke, Eric H; Duncan, Ian

    2012-02-21

    Hormonal control of sexual maturation is a common feature in animal development. A particularly dramatic example is the metamorphosis of insects, in which pulses of the steroid hormone ecdysone drive the wholesale transformation of the larva into an adult. The mechanisms responsible for this transformation are not well understood. Work in Drosophila indicates that the larval and adult forms are patterned by the same underlying sets of developmental regulators, but it is not understood how the same regulators pattern two distinct forms. Recent studies indicate that this ability is facilitated by a global change in the responsiveness of target genes during metamorphosis. Here we show that this shift is controlled in part by the ecdysone-induced transcription factor E93. Although long considered a dedicated regulator of larval cell death, we find that E93 is expressed widely in adult cells at the pupal stage and is required for many patterning processes at this time. To understand the role of E93 in adult patterning, we focused on a simple E93-dependent process, the induction of the Dll gene within bract cells of the pupal leg by EGF receptor signaling. In this system, we show that E93 functions to cause Dll to become responsive to EGF receptor signaling. We demonstrate that E93 is both necessary and sufficient for directing this switch. E93 likely controls the responsiveness of many other target genes because it is required broadly for patterning during metamorphosis. The wide conservation of E93 orthologs suggests that similar mechanisms control life-cycle transitions in other organisms, including vertebrates.

  7. Turbine sound may influence the metamorphosis behaviour of estuarine crab megalopae.

    Directory of Open Access Journals (Sweden)

    Matthew K Pine

    Full Text Available It is now widely accepted that a shift towards renewable energy production is needed in order to avoid further anthropogenically induced climate change. The ocean provides a largely untapped source of renewable energy. As a result, harvesting electrical power from the wind and tides has sparked immense government and commercial interest but with relatively little detailed understanding of the potential environmental impacts. This study investigated how the sound emitted from an underwater tidal turbine and an offshore wind turbine would influence the settlement and metamorphosis of the pelagic larvae of estuarine brachyuran crabs which are ubiquitous in most coastal habitats. In a laboratory experiment the median time to metamorphosis (TTM for the megalopae of the crabs Austrohelice crassa and Hemigrapsus crenulatus was significantly increased by at least 18 h when exposed to either tidal turbine or sea-based wind turbine sound, compared to silent control treatments. Contrastingly, when either species were subjected to natural habitat sound, observed median TTM decreased by approximately 21-31% compared to silent control treatments, 38-47% compared to tidal turbine sound treatments, and 46-60% compared to wind turbine sound treatments. A lack of difference in median TTM in A. crassa between two different source levels of tidal turbine sound suggests the frequency composition of turbine sound is more relevant in explaining such responses rather than sound intensity. These results show that estuarine mudflat sound mediates natural metamorphosis behaviour in two common species of estuarine crabs, and that exposure to continuous turbine sound interferes with this natural process. These results raise concerns about the potential ecological impacts of sound generated by renewable energy generation systems placed in the nearshore environment.

  8. Common and distinct roles of juvenile hormone signaling genes in metamorphosis of holometabolous and hemimetabolous insects.

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    Barbora Konopova

    Full Text Available Insect larvae metamorphose to winged and reproductive adults either directly (hemimetaboly or through an intermediary pupal stage (holometaboly. In either case juvenile hormone (JH prevents metamorphosis until a larva has attained an appropriate phase of development. In holometabolous insects, JH acts through its putative receptor Methoprene-tolerant (Met to regulate Krüppel-homolog 1 (Kr-h1 and Broad-Complex (BR-C genes. While Met and Kr-h1 prevent precocious metamorphosis in pre-final larval instars, BR-C specifies the pupal stage. How JH signaling operates in hemimetabolous insects is poorly understood. Here, we compare the function of Met, Kr-h1 and BR-C genes in the two types of insects. Using systemic RNAi in the hemimetabolous true bug, Pyrrhocoris apterus, we show that Met conveys the JH signal to prevent premature metamorphosis by maintaining high expression of Kr-h1. Knockdown of either Met or Kr-h1 (but not of BR-C in penultimate-instar Pyrrhocoris larvae causes precocious development of adult color pattern, wings and genitalia. A natural fall of Kr-h1 expression in the last larval instar normally permits adult development, and treatment with an exogenous JH mimic methoprene at this time requires both Met and Kr-h1 to block the adult program and induce an extra larval instar. Met and Kr-h1 therefore serve as JH-dependent repressors of deleterious precocious metamorphic changes in both hemimetabolous and holometabolous juveniles, whereas BR-C has been recruited for a new role in specifying the holometabolous pupa. These results show that despite considerable evolutionary distance, insects with diverse developmental strategies employ a common-core JH signaling pathway to commit to adult morphogenesis.

  9. Turbine Sound May Influence the Metamorphosis Behaviour of Estuarine Crab Megalopae

    Science.gov (United States)

    Pine, Matthew K.; Jeffs, Andrew G.; Radford, Craig A.

    2012-01-01

    It is now widely accepted that a shift towards renewable energy production is needed in order to avoid further anthropogenically induced climate change. The ocean provides a largely untapped source of renewable energy. As a result, harvesting electrical power from the wind and tides has sparked immense government and commercial interest but with relatively little detailed understanding of the potential environmental impacts. This study investigated how the sound emitted from an underwater tidal turbine and an offshore wind turbine would influence the settlement and metamorphosis of the pelagic larvae of estuarine brachyuran crabs which are ubiquitous in most coastal habitats. In a laboratory experiment the median time to metamorphosis (TTM) for the megalopae of the crabs Austrohelice crassa and Hemigrapsus crenulatus was significantly increased by at least 18 h when exposed to either tidal turbine or sea-based wind turbine sound, compared to silent control treatments. Contrastingly, when either species were subjected to natural habitat sound, observed median TTM decreased by approximately 21–31% compared to silent control treatments, 38–47% compared to tidal turbine sound treatments, and 46–60% compared to wind turbine sound treatments. A lack of difference in median TTM in A. crassa between two different source levels of tidal turbine sound suggests the frequency composition of turbine sound is more relevant in explaining such responses rather than sound intensity. These results show that estuarine mudflat sound mediates natural metamorphosis behaviour in two common species of estuarine crabs, and that exposure to continuous turbine sound interferes with this natural process. These results raise concerns about the potential ecological impacts of sound generated by renewable energy generation systems placed in the nearshore environment. PMID:23240063

  10. Post-embryonic transcriptomes of the prawn Macrobrachium rosenbergii: multigenic succession through metamorphosis.

    Directory of Open Access Journals (Sweden)

    Tomer Ventura

    Full Text Available Like many metazoans, the freshwater prawn Macrobrachium rosenbergii begins its post-embryonic life with a set of morphologically distinct planktonic larval stages, followed by a benthic post-larval stage during which the maturing organism differs from the larvae both ecologically and physiologically. Understanding of the molecular basis underlying morphogenesis in crustaceans is limited to the observation that methyl farnesoate, the non-epoxidated form of the insect juvenile hormone, acts as the active crustacean juvenoid. Molt steroids were also linked to morphogenesis and several other molecular pathways, such as Hedgehog and Wnt, are known to underlie morphogenesis in all metazoans examined and, as such, are thought to do the same in crustaceans. Using next generation sequencing, we deep-sequenced the transcriptomes of several larval and post-larval stages. De novo assembly, followed by bioinformatics analysis, revealed that many novel transcripts are over-expressed in either larvae- or post-larvae-stage prawn, shedding light on the molecular basis underlying M. rosenbergii metamorphosis. Fast larval molting rates and periodic morphological changes were reflected in over-expression of transcripts annotated to the cell cycle, DNA replication and morphogenic pathways (i.e., Hedgehog and Wnt. Further characterization of transcripts assigned to morphogenic pathways by real-time RT-PCR reconfirmed their over-expression in larvae, albeit with a more complex expression pattern when examined in the individual developmental stages. The expression level of an orthologue of cytochrome P450, 15A1, known to epoxidize methyl farnesoate in insects, was increased in the late larval and early post-larval stages, in accordance with the role of methyl farnesoate in crustacean metamorphosis. This study exemplifies the applicability of a high-throughput sequencing approach for studying complex traits, including metamorphosis, providing new insight into this

  11. Histone acetylation mediates epigenetic regulation of transcriptional reprogramming in insects during metamorphosis, wounding and infection

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    Mukherjee Krishnendu

    2012-10-01

    Full Text Available Abstract Background Gene expression in eukaryotes is regulated by histone acetylation/deacetylation, an epigenetic process mediated by histone acetyltransferases (HATs and histone deacetylases (HDACs whose opposing activities are tightly regulated. The acetylation of histones by HATs increases DNA accessibility and promotes gene expression, whereas the removal of acetyl groups by HDACs has the opposite effect. Results We explored the role of HDACs and HATs in epigenetic reprogramming during metamorphosis, wounding and infection in the lepidopteran model host Galleria mellonella. We measured the expression of genes encoding components of HATs and HDACs to monitor the transcriptional activity of each enzyme complex and found that both enzymes were upregulated during pupation. Specific HAT inhibitors were able to postpone pupation and to reduce insect survival following wounding, whereas HDAC inhibitors accelerated pupation and increased survival. The administration of HDAC inhibitors modulated the expression of effector genes with key roles in tissue remodeling (matrix metalloproteinase, the regulation of sepsis (inhibitor of metalloproteinases from insects and host defense (antimicrobial peptides, and simultaneously induced HAT activity, suggesting that histone acetylation is regulated by a feedback mechanism. We also discovered that both the entomopathogenic fungus Metarhizium anisopliae and the human bacterial pathogen Listeria monocytogenes can delay metamorphosis in G. mellonella by skewing the HDAC/HAT balance. Conclusions Our study provides for the first evidence that pathogenic bacteria can interfere with the regulation of HDACs and HATs in insects which appear to manipulate host immunity and development. We conclude that histone acetylation/deacetylation in insects mediates transcriptional reprogramming during metamorphosis and in response to wounding and infection.

  12. Spatial pattern analysis of nuclear migration in remodelled muscles during Drosophila metamorphosis.

    Science.gov (United States)

    Kuleesha; Feng, Lin; Wasser, Martin

    2017-07-10

    Many human muscle wasting diseases are associated with abnormal nuclear localization. During metamorphosis in Drosophila melanogaster, multi-nucleated larval dorsal abdominal muscles either undergo cell death or are remodeled to temporary adult muscles. Muscle remodeling is associated with anti-polar nuclear migration and atrophy during early pupation followed by polar migration and muscle growth during late pupation. Muscle remodeling is a useful model to study genes involved in myonuclear migration. Previously, we showed that loss of Cathepsin-L inhibited anti-polar movements, while knockdown of autophagy-related genes affected nuclear positioning along the medial axis in late metamorphosis. To compare the phenotypic effects of gene perturbations on nuclear migration more objectively, we developed new descriptors of myonuclear distribution. To obtain nuclear pattern features, we designed an algorithm to detect and track nuclear regions inside live muscles. Nuclear tracks were used to distinguish between fast moving nuclei associated with fragments of dead muscles (sarcolytes) and slow-moving nuclei inside remodelled muscles. Nuclear spatial pattern features, such as longitudinal (lonNS) and lateral nuclear spread (latNS), allowed us to compare nuclear migration during muscle remodelling in different genetic backgrounds. Anti-polar migration leads to a lonNS decrease. As expected, lack of myonuclear migration caused by the loss of Cp1 was correlated with a significantly lower lonNS decrease. Unexpectedly, the decrease in lonNS was significantly enhanced by Atg9, Atg5 and Atg18 silencing, indicating that the loss of autophagy promotes the migration and clustering of nuclei. Loss of autophagy also caused a scattering of nuclei along the lateral axis, leading to a two-row as opposed to single row distribution in control muscles. Increased latNS resulting from knockdown of Atg9 and Atg18 was correlated with increased muscle diameter, suggesting that the wider muscle

  13. The ontogeny of choanocyte chambers during metamorphosis in the demosponge Amphimedon queenslandica

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    Shunsuke Sogabe

    2016-03-01

    Full Text Available Abstract Background The aquiferous body plan of poriferans revolves around internal chambers comprised of choanocytes, a cell type structurally similar to choanoflagellates. These choanocyte chambers perform a range of physiological and developmental functions, including the capture of food and the generation of stem cells. Despite the increasing interest for choanocytes as sponge stem cells, there is limited knowledge on the development of choanocyte chambers. Using a combination of cell lineage tracing, antibody staining and EdU labeling, here we examine the development of choanocytes and the chambers they comprise during metamorphosis in the marine demosponge Amphimedon queenslandica. Results Lineage-tracing experiments show that larval epithelial cells transform into mesenchymal pluripotent stem cells, resembling archeocytes, within 24 h of initiating metamorphosis. By 36 h, some of these labeled archeocyte-like cells have differentiated into choanocytes that will form the first postlarval choanocyte chambers. Non-labeled cells also contribute to these primary choanocyte chambers, consistent with these chambers being a chimera of multiple transdifferentiated larval cell types and not the proliferation of a single choanocyte precursor. Moreover, cell proliferation assays demonstrate that, following the initial formation of choanocyte chambers, chambers grow at least partially by the proliferation of choanocytes within the chamber, although recruitment of individual cells into established chambers also appears to occur. EdU labeling of postlarvae and juveniles reveals that choanocyte chambers are the primary location of cell proliferation during metamorphosis. Conclusion Our results show that multiple larval cell lineages typically contribute to formation of individual choanocyte chambers at metamorphosis, contrary to previous reports in other species that show sponge choanocyte chambers form clonally. Choanocytes in postlarval and juvenile

  14. AESTHETICS OF OPPOSITION: THE POLITICS OF METAMORPHOSIS IN GERALD VIZENOR’S BEARHEART

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    Seyed Mohammad Marandi

    2014-09-01

    Full Text Available The Chippewa novelist Gerald Vizenor puts across his interconnected politico-philosophical notions of “survivance” and “terminal creeds” in his early novel, Bearheart. To do so, Vizenor implemented some of the aesthetic strategies of magical realism. He filled his novel with an excessive amount of bizarrely sexual and violent scenes—which turn out to be magical—in order to “upset” the established standards of normality. Moreover, he used American Indian mythic folktales of transformation and metamorphosis, a magical realist technique, to re-shape the cultural and tribal identity in Bearheart’s modernized context.

  15. Involvement of a novel p38 mitogen-activated protein kinase in larval metamorphosis of the polychaete Hydroides elegans (Haswell)

    KAUST Repository

    Wang, Hao

    2010-04-19

    Hydroides elegans is a common marine fouling organism in most tropical and subtropical waters. The life cycle of H. elegans includes a planktonic larval stage in which swimming larvae normally take 5 days to attain competency to settle. Larval metamorphosis marks the beginning of its benthic life; however, the endogenous molecular mechanisms that regulate metamorphosis remain largely unknown. In this study, a PCR-based suppressive subtractive hybridization (SSH) library was constructed to screen the genes expressed in competent larvae but not in precompetent larvae. Among the transcripts isolated from the library, 21 significantly matched sequences in the GenBank. Many of these isolated transcripts have putative roles in the reactive oxygen species (ROS) signal transduction pathway or in response to ROS stress. A putative novel p38 mitogen-activated protein kinase (MAPK), which was also isolated with SSH screen, was then cloned and characterized. The MAPK inhibitors assay showed that both p38 MAPK inhibitors SB202190 and SB203580 effectively inhibited the biofilm-induced metamorphosis of H. elegans. A cell stressors assay showed that H2O2 effectively induced larval metamorphosis of H. elegans, but the inductivity of H2O2 was also inhibited by both SB inhibitors. The catalase assay showed that the catalase could effetely inhibit H. elegans larvae from responding to inductive biofilm. These results showed that the p38 MAPK-dependent pathway plays critical role in controlling larval metamorphosis of the marine polychaete H. elegans, and the reactive oxygen radicals produced by biofilm could be the cue inducing larval metamorphosis. © 2010 Wiley-Liss, Inc.

  16. Studies on the regulation of anuran metamorphosis by thyroid hormones and prolactin

    International Nuclear Information System (INIS)

    Ray, L.B.

    1985-01-01

    Resorption of the tail of the anuran larva during metamorphosis is induced by the thyroid hormones. In contrast, the pituitary hormone prolactin favors growth of the tail fin and inhibits resorption. The present investigations were designed to explore the mechanisms by which the thyroid hormones and prolactin bring about their cellular effects. Incubation of explants of tail fin with derivatives of cAMP was shown to inhibit T 4 -induced resorption of explants in a manner similar to that of prolactin. Likewise, inhibition of phosphodiesterases also inhibited resorption. Prolactin, however, failed to alter the levels of cAMP in cultured explants of tail fin. Although cAMP antagonizes the resorptive effects of T 4 , prolactin apparently does not act by elevating cellular levels of that cyclic nucleotide. Newly synthesized proteins from explants of tail fin were examined by isotopical labeling followed by two-dimensional gel electrophoresis and fluorography. Incorporation of 35 S-methionine into four proteins was increased within 8 to 48 hours after exposure of explants to T 4 . Three of the same proteins appeared to be synthesized more rapidly in explants of fin from tadpoles at metamorphic climax than in fin from tadpoles of premetamorphic stages. These results indicate that treatment of explants with T 4 or elevation of endogenous levels of thyroid hormones during spontaneous metamorphosis increased the relative rates of synthesis of several proteins. Those proteins are potentially involved in initiating the effects of T 4 which lead to cell death and resorption of the tail

  17. Post-embryonic larval development and metamorphosis of the hydroid Eudendrium racemosum (Cavolini) (Hydrozoa, Cnidaria)

    Science.gov (United States)

    Sommer, C.

    1990-09-01

    The morphology and histology of the planula larva of Eudendrium racemosum (Cavolini) and its metamorphosis into the primary polyp are described from light microscopic observations. The planula hatches as a differentiated gastrula. During the lecithotrophic larval period, large ectodermal mucous cells, embedded between epitheliomuscular cells, secrete a sticky slime. Two granulated cell types occur in the ectoderm that are interpreted as secretory and sensorynervous cells, but might also be representatives of only one cell type with a multiple function. The entoderm consists of yolk-storing gastrodermal cells, digestive gland cells, interstitial cells, cnidoblasts, and premature cnidocytes. The larva starts metamorphosis by affixing its blunt aboral pole to a substratum. While the planula flattens down, the mucous cells penetrate the mesolamella and migrate through the entoderm into the gastral cavity where they are lysed. Subsequently, interstitial cells, cnidoblasts, and premature cnidocytes migrate in the opposite direction, i.e. from entoderm to ectoderm. Then, the polypoid body organization, comprising head (hydranth), stem and foot, all covered by peridermal secretion, becomes recognisable. An oral constriction divides the hypostomal portion of the gastral cavity from the stomachic portion. Within the hypostomal entoderm, cells containing secretory granules differentiate. Following growth and the multiplication of tentacles, the head periderm disappears. A ring of gland cells differentiates at the hydranth's base. The positioning of cnidae in the tentacle ectoderm, penetration of the mouth opening and the multiplication of digestive gland cells enable the polyp to change from lecithotrophic to planktotrophic nutrition.

  18. CIRCADIAN METAMORPHOSIS IN THE URBAN LANDSCAPE FROM THE COMPLEX EPISTEMOLOGY METAMORFOSIS

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    Richard Cardona

    2011-04-01

    Full Text Available This work seeks to define a theoretical position that allows establishing another vision of the urban phenomenon as a concept of the bio being - anthropologic-cibercultural that lives and simultaneously it recreates the urban landscape, taking events and urban transformations happened during the day and the night. For it one proposes as point of item the definition of the poly-temporality concept from Edgar Morín (1998, of the duration and simultaneity of Bergson (2004, then ends in the matter of the circadian cycles, that is to say during a period of 24 hours, and the transformations both in morphology and in activities that happen in the urban contemporary landscape. In the definition of metamorphosis it splits of the position of Edgar Morín (2010 while the metamorphosis like alternative of redefinition of routes towards a healthy and ethical way of building economic - social and political solutions, which has direct inference in the urban phenomenon

  19. A new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Chung-Davidson, Yu-Wen; Davidson, Peter J.; Scott, Anne M.; Walaszczyk, Erin J.; Brant, Cory O.; Buchinger, Tyler; Johnson, Nicholas S.; Li, Weiming

    2014-01-01

    Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.

  20. A eukaryotic initiation factor 5C is upregulated during metamorphosis in the cotton bollworm, Helicoverpa armigera.

    Science.gov (United States)

    Dong, Du-Juan; Wang, Jin-Xing; Zhao, Xiao-Fan

    2009-03-08

    The orthologs of eukaryotic initiation factor 5C (eIF5C) are essential to the initiation of protein translation, and their regulation during development is not well known. A cDNA encoding a polypeptide of 419 amino acids containing an N-terminal leucine zipper motif and a C-terminal eIF5C domain was cloned from metamorphic larvae of Helicoverpa armigera. It was subsequently named Ha-eIF5C. Quantitative real-time PCR (QRT-PCR) revealed a high expression of the mRNA of Ha-eIF5C in the head-thorax, integument, midgut, and fat body during metamorphosis. Immunohistochemistry suggested that Ha-eIF5C was distributed into both the cytoplasm and the nucleus in the midgut, fat body and integument. Ha-eIF5C expression was upregulated by 20-hydroxyecdysone (20E). Furthermore, the transcription of Ha-eIF5C was down regulated after silencing of ecdysteroid receptor (EcR) or Ultraspiracle protein (USP) by RNAi. These results suggested that during metamorphosis of the cotton bollworm, Ha-eIF5C was upregulated by 20E through the EcR and USP transcription factors.

  1. A eukaryotic initiation factor 5C is upregulated during metamorphosis in the cotton bollworm, Helicoverpa armigera

    Directory of Open Access Journals (Sweden)

    Zhao Xiao-Fan

    2009-03-01

    Full Text Available Abstract Background The orthologs of eukaryotic initiation factor 5C (eIF5C are essential to the initiation of protein translation, and their regulation during development is not well known. Results A cDNA encoding a polypeptide of 419 amino acids containing an N-terminal leucine zipper motif and a C-terminal eIF5C domain was cloned from metamorphic larvae of Helicoverpa armigera. It was subsequently named Ha-eIF5C. Quantitative real-time PCR (QRT-PCR revealed a high expression of the mRNA of Ha-eIF5C in the head-thorax, integument, midgut, and fat body during metamorphosis. Immunohistochemistry suggested that Ha-eIF5C was distributed into both the cytoplasm and the nucleus in the midgut, fat body and integument. Ha-eIF5C expression was upregulated by 20-hydroxyecdysone (20E. Furthermore, the transcription of Ha-eIF5C was down regulated after silencing of ecdysteroid receptor (EcR or Ultraspiracle protein (USP by RNAi. Conclusion These results suggested that during metamorphosis of the cotton bollworm, Ha-eIF5C was upregulated by 20E through the EcR and USP transcription factors.

  2. The evolution of amphibian metamorphosis: insights based on the transformation of the aortic arches of Pelobates fuscus (Anura)

    Czech Academy of Sciences Publication Activity Database

    Kolesová, H.; Lametschwandtner, A.; Roček, Zbyněk

    2007-01-01

    Roč. 210, č. 4 (2007), s. 379-393 ISSN 0021-8782 Institutional research plan: CEZ:AV0Z30130516 Keywords : Anura * circulatory system * development * evolution * metamorphosis Subject RIV: EG - Zoology Impact factor: 2.547, year: 2007

  3. Effects of environmental factors on growth, survival, and metamorphosis of geoduck clam (Panopea japonica A. Adams, 1850 larvae

    Directory of Open Access Journals (Sweden)

    Zhongming Huo

    2017-11-01

    Full Text Available A series of experiments were conducted to evaluate the effects of temperature, salinity, diet, and stocking density on the growth, survival, and metamorphosis of geoduck clam Panopea japonica larvae. The larvae all died at a temperature of 22 °C after day 12, suggesting that the larvae of P. japonica could not survive when the temperature was higher than 22 °C. P. japonica could be incubated at 19 °C for the fast growth, high survival and metamorphosis of larvae. The embryos all died when the salinity was below 25 ppt. The larvae showed poor survival when the salinity was below 25 ppt, with all larvae dying before day 12, suggesting that larvae are sensitive to low salinity. The optimum salinity for the growth, survival and metamorphosis of larvae was 32 ppt. The use of a mixture of Isochrysis galbana and Nitzschia closterium (1:1 as a food source for the P. japonica larvae improved their growth, survival, and metamorphosis. A density of 20 individuals/ml appeared to be optimal for normal D-larvae of Panopea japonica, and 3–9 larvae/ml was optimal for the growth and survival of the P. japonica larvae raised in the hatchery.

  4. Stellar Metamorphosis:

    Science.gov (United States)

    2002-01-01

    [TOP LEFT AND RIGHT] The Hubble Space Telescope's Wide Field and Planetary Camera 2 has captured images of the birth of two planetary nebulae as they emerge from wrappings of gas and dust, like butterflies breaking out of their cocoons. These images highlight a fleeting phase in the stellar burnout process, occurring just before dying stars are transformed into planetary nebulae. The left-hand image is the Cotton Candy nebula, IRAS 17150-3224; the right-hand image, the Silkworm nebula, IRAS 17441-2411. Called proto-planetary nebulae, these dying stars have been caught in a transition phase between a red giant and a planetary nebula. This phase is only about 1,000 years long, very short in comparison to the 1 billion-year lifetime of a star. These images provide the earliest snapshots of the transition process. Studying images of proto-planetary nebulae is important to understanding the process of star death. A star begins to die when it has exhausted its thermonuclear fuel - hydrogen and helium. The star then becomes bright and cool (red giant phase) and swells to several tens of times its normal size. It begins puffing thin shells of gas off into space. These shells become the star's cocoon. In the Hubble images, the shells are the concentric rings seen around each nebula. But the images also reveal the nebulae breaking out from those shells. The butterfly-like wings of gas and dust are a common shape of planetary nebulae. Such butterfly shapes are created by the 'interacting winds' process, in which a more recent 'fast wind' - material propelled by radiation from the hot central star - punches a hole in the cocoon, allowing the nebula to emerge. (This 'interacting wind' theory was first proposed by Dr. Sun Kwok to explain the origin of planetary nebulae, and has been subsequently proven successful in explaining their shapes.) The nebulae are being illuminated by light from the invisible central star, which is then reflected toward us. We are viewing the nebulae edge-on, where the direct starlight is blocked by the dusty cocoon. Otherwise, the starlight would overwhelm the nebular light, making it very difficult to see the butterfly-shaped nebula. In a few hundred years, intense ultraviolet radiation from the central star will energize the surrounding gas, causing it to glow brightly, and a planetary nebula is born. These observations were made with the Wide Field and Planetary Camera 2 using three filters: yellow-green, blue, and near-infrared. The images were taken in 1997 by Sun Kwok and in 1996 by Matt Bobrowsky. Credits: Sun Kwok and Kate Su (University of Calgary), Bruce Hrivnak (Valparaiso University), and NASA ----------------- The Hubble Space Telescope Sees Remarkable Structure in the Heart of a Planetary Nebula [BOTTOM LEFT AND RIGHT] This Wide Field and Planetary Camera 2 image of NGC 6818 shows two distinct layers of gas (with dust): a spherical outer region and a brighter, vase-shaped interior 'bubble.' Astronomers believe that a fast wind - material propelled by radiation from the hot central star - is creating the inner elongated shape. The central star of the planetary nebula appears as a tiny blue dot. The material in the wind is traveling so fast that it smashes through older, slower-moving stellar debris, causing a 'blowout' at both ends of the bubble (lower right and upper left). This nebula looks like a twin of NGC 3918, another planetary nebula that has been observed by the Hubble telescope. The structure of NGC 3918 is remarkably similar to that of NGC 6818. It has an outer spherical envelope and an inner, brighter, elongated bubble. A fast-moving wind also appears to have created an orifice at one end (bottom right-hand corner) of the inner bubble. There are even faint wisps of material that were probably blown out of this hole. In the opposite direction (top left-hand corner), there is a protrusion that seems on the verge of breaking through to form a hole. By finding and studying such similar objects, astronomers hope to learn crucial details about the evolutionary history of planetary nebulae. The Hubble telescope observation was taken March 10, 1997. This picture is a composite of images taken with three filters that are representative of the true colors of the object. Two of these are, respectively, in the light of a red and a blue spectral line of hydrogen - the major constituent of the nebula. The third image is in the light of a luminous green line due to doubly ionized oxygen. NGC 6818 is about 6,000 light-years away in the constellation Sagittarius. The nebula has a diameter of about 0.5 light-years. Credits: Robert Rubin (NASA Ames Research Center), Reginald Dufour and Matt Browning (Rice University), Patrick Harrington (University of Maryland), and NASA

  5. Flux metamorphosis

    International Nuclear Information System (INIS)

    Bais, F.A.

    1980-01-01

    Some consequences of a non-abelian fundamental group π 1 (G/H) are investigated in the context of spontaneously broken gauge theories. Vortices associated with elements of π 1 (G/H) which do not commute cannot pass through each other, without remaining attached. Various simple models featuring this phenomenon are presented. A rather general method for generating the relevant ansaetze for the fields is given as well. (orig.)

  6. Survival and metamorphosis rate of swimming crab Portunus pelagicus larvae with the use of phytoecdysteroid in the artificial feed

    Directory of Open Access Journals (Sweden)

    Andi Nikhlani

    2017-07-01

    Full Text Available ABSTRACT The survival rate of blue swimming crabs and the larval metamorphosis processes are still low in hatcheries. The objective of this study was to evaluate the effects of different phytoecdysteroids doses on both the survival and the rate of Blue swimmer crab larvae metamorphosis. The study consisted of four different phytoecdysteroids treatments, namely: control (0 mg/100 g of feed, 1 mg/100 g of feed, 2 mg/100 g of feed, and 4 mg/100 g of feed. Each treatment was replicated three times. The survival rate of the larvae was analyzed through analysis of variance, while the rate of larval metamorphosis was descriptively analyzed. The results showed that the dose of phytoecdysteroid of 2 mg/100 g of artificial feed resulted in the highest survival and the fastest metamorphosis speed of crab larvae for zoea-2 and zoea-3, and the dose of 4 mg/100 g of artificial feed for stadia megalopa and crablet. Keywords: phytoecdysteroids, survival rate, metamorphosis, blue swimming crab  ABSTRAK Kelangsungan hidup rajungan dalam pembenihan masih rendah, dan proses metamorfosis larva masih lambat. Tujuan penelitian ini adalah untuk mengevaluasi pengaruh pemberian fitoekdisteroid dosis berbeda terhadap kelangsungan hidup dan kecepatan metamorfosis larva rajungan. Penelitian ini terdiri atas empat perlakuan dosis fitoekdisteroid yang berbeda, yaitu: kontrol (0 mg/100 g pakan, 1 mg/100 g pakan, 2 mg/100 g pakan, dan 4 mg/100 g pakan dengan masing-masing perlakuan dilakukan tiga kali ulangan. Kelangsungan hidup larva dianalisis menggunakan analisis sidik ragam, sedangkan kecepatan metamorfosis larva dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa dosis fitoekdisteroid sebanyak 2 mg/100 g pakan buatan menghasilkan kelangsungan hidup tertinggi dan proses metamorfosis larva rajungan tercepat untuk stadia zoea-2 dan zoea-3, serta  dosis 4 mg/100 g pakan buatan untuk stadia megalopa dan crablet. Kata kunci: fitoekdisteroid, kelangsungan

  7. Metabolomic insights into the effects of thyroid hormone on Rana [Lithobates] catesbeiana metamorphosis using whole-body Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging (MALDI-MSI).

    Science.gov (United States)

    Luehr, Teesha C; Koide, Emily M; Wang, Xiaodong; Han, Jun; Borchers, Christoph H; Helbing, Caren C

    2018-02-19

    Anuran metamorphosis involves the transformation of an aquatic tadpole into a juvenile frog. This process is completely dependent upon thyroid hormones (THs). Although much research has been focused on changes in gene expression programs during this postembryonic developmental period, transitions in the metabolic profiles are relatively poorly understood. Matrix Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging (MALDI-MSI) is a technique that generates highly multiplexed mass spectra while retaining spatial location information on a thin tissue section. Reconstructed ion heat maps are correlated with morphology of the tissue section for biological interpretation. The present study is the first to use whole-body MALDI-MSI on tadpoles to gain insights into anuran metamorphosis. Approximately 1000 features were detected in each of five tissues examined (brain, eye, liver, notochord, and tail muscle) from premetamorphic North American bullfrog (Rana [Lithobates] catesbeiana) tadpoles. Of these detected metabolites, 1700 were unique and 136 were significantly affected by exposure to 50 nM thyroxine for 48 h. Of the significantly-affected metabolites, 64 features were tentatively identified using the MassTRIX annotation tool. All tissues revealed changes in lipophilic compounds including phosphatidylcholines, phosphatidylinositols, phosphatidylglycerols, phosphatidylethanolamines, and phosphatidylserines. These lipophilic compounds made up the largest portion of significantly-affected metabolites indicating that lipid signaling is a major target of TH action in frog tadpoles. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Changes in carbon and nitrogen stable isotopes of chironomid larvae during growth, starvation and metamorphosis.

    Science.gov (United States)

    Doi, Hideyuki; Kikuchi, Eisuke; Takagi, Shigeto; Shikano, Shuichi

    2007-01-01

    We conducted experiments to determine isotope changes in the deposit-feeding chironomid larvae Chironomus acerbiphilus during feeding, starvation and metamorphosis. Isotope changes in chironomid larvae occurred mainly during growth and rarely afterward. This finding indicates that chironomid isotope turnover mainly occurs in conjunction with growth and suggests that chironomid larvae only break down newly assimilated food for energy during periods of no growth. Chironomid delta(13)C values significantly increased throughout the starvation experiment, indicating that chironomids preferentially break down components with lower delta(13)C content during starvation. We found significant changes in chironomid isotope ratios ((15)N enrichment) during pupation. This evidence suggests that the physiological condition of animals (such as during an active growth phase or pre- or post-molting) is important to their stable isotope ratios.

  9. Narrative Metamorphosis Through Images: The Case of Opening Miniatures in the Estoire del

    Directory of Open Access Journals (Sweden)

    Miha Zor

    2015-12-01

    Full Text Available The article deals with pictorial metamorphosis in the opening pages of two early 14th-century manuscripts of the Estoire del saint Graal. Firstly, the episodes depicted are analysed iconographically and formally. Secondly, it explores how pictorial narrative is established in the multi-compartmentalised miniature, that is how the images are linked internally in order to convey a narrative that has its beginning and its ending. Thirdly, it is shown how the images in the opening miniature communicate with other miniatures in the manuscript and how the course of interpretation, signaled by the opening miniature, is succeeded and confirmed by the selection of episodes which are subsequently depicted, as well as by the way in which the episodes depicted are pictorially interpreted.

  10. Towards cosmopolitan middle-range theorizing: A metamorphosis in the practice of social theory?

    DEFF Research Database (Denmark)

    Blok, Anders

    2015-01-01

    Over the years, Ulrich Beck has established himself as an important sociologist due in large part to the imaginative and skillful way in which he has continuously added new conceptual bricks to his theoretical edifice and cosmopolitan vision. His work at the present juncture is no exception......, spurred as it is by the urgency of responding to the global risks of climate change via reworking key categories of social theory. More strongly than existing notions of world risk society and second modernity, his new concept of metamorphosis (‘Verwandlung’) captures the way contemporary social upheavals...... imply a fundamental transformation in our very coordinates of social change, in the face of as-yet uncertain collective futures. Likewise, as Beck propounds in this issue of Current Sociology, the concept of emancipatory catastrophism starkly underlines the core moral ambiguity of global risks: (future...

  11. Detritus Quality and Locality Determines Survival and Mass, but Not Export, of Wood Frogs at Metamorphosis.

    Science.gov (United States)

    Milanovich, Joseph R; Barrett, Kyle; Crawford, John A

    2016-01-01

    Single-site experiments have demonstrated detritus quality in wetlands can have strongly negative, neutral, and even positive influences on wildlife. However, an examination of the influence of detritus quality across several regions is lacking and can provide information on whether impacts from variation in detritus quality are consistent across species with wide ranges. To address this gap in regional studies we examined effects of emergent and allochthonous detritus of different nutrient qualities on amphibians and assessed a mechanism that may contribute to potential impacts. We used aquatic mesocosms to raise wood frogs (Rana sylvatica) from two regions of the United States with whole plants from purple loosestrife (Lythrum salicaria), leaf litter from native hardwood trees, and a mixture of both. We examined several metrics of amphibian fitness and life history, including survival, number of days to metamorphosis, and size at metamorphosis. Further, we quantified whether the effects of detritus type could translate to variation in anuran biomass or standing stock of nitrogen or phosphorus export. Our results show detritus with high nutrient quality (purple loosestrife) negatively influenced survival of wood frogs, but increased size of metamorphic individuals in two different regions of the United States. Despite the decrease in survival, the increase in size of post-metamorphic anurans raised with high quality detritus resulted in anuran biomass and standing stock of N and P export being similar across treatments at both locations. These results further demonstrate the role of plant quality in shaping wetland ecosystem dynamics, and represent the first demonstration that effects are consistent within species across ecoregional boundaries.

  12. Differential gene expression at coral settlement and metamorphosis--a subtractive hybridization study.

    Directory of Open Access Journals (Sweden)

    David C Hayward

    Full Text Available BACKGROUND: A successful metamorphosis from a planktonic larva to a settled polyp, which under favorable conditions will establish a future colony, is critical for the survival of corals. However, in contrast to the situation in other animals, e.g., frogs and insects, little is known about the molecular basis of coral metamorphosis. We have begun to redress this situation with previous microarray studies, but there is still a great deal to learn. In the present paper we have utilized a different technology, subtractive hybridization, to characterize genes differentially expressed across this developmental transition and to compare the success of this method to microarray. METHODOLOGY/PRINCIPAL FINDINGS: Suppressive subtractive hybridization (SSH was used to identify two pools of transcripts from the coral, Acropora millepora. One is enriched for transcripts expressed at higher levels at the pre-settlement stage, and the other for transcripts expressed at higher levels at the post-settlement stage. Virtual northern blots were used to demonstrate the efficacy of the subtractive hybridization technique. Both pools contain transcripts coding for proteins in various functional classes but transcriptional regulatory proteins were represented more frequently in the post-settlement pool. Approximately 18% of the transcripts showed no significant similarity to any other sequence on the public databases. Transcripts of particular interest were further characterized by in situ hybridization, which showed that many are regulated spatially as well as temporally. Notably, many transcripts exhibit axially restricted expression patterns that correlate with the pool from which they were isolated. Several transcripts are expressed in patterns consistent with a role in calcification. CONCLUSIONS: We have characterized over 200 transcripts that are differentially expressed between the planula larva and post-settlement polyp of the coral, Acropora millepora

  13. Factors regulating the production of different inducers in Pseudomonas aeruginosa with reference to larval metamorphosis in Balanus amphitrite

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Anil, A.C.; Raghukumar, S.

    and other environmental stimuli; hence, the behavioral and morphogenetic responses may be trig- gered by different inducers (Rodriguez et al. 1993). Settlement and metamorphosis are shown to be con- trolled by larval sensory recognition, which transduces... the external signals into signals within the organism (Pawlik 1992). Field and laboratory studies have shown that barna- cle cyprids prefer to metamorphose on or near con- specifics. The responsible settlement pheromone or positive cue has been recognized...

  14. Compromised metamorphosis and thyroid hormone changes in wood frogs (Lithobates sylvaticus) raised on reclaimed wetlands on the Athabasca oil sands

    International Nuclear Information System (INIS)

    Hersikorn, Blair D.; Smits, Judit E.G.

    2011-01-01

    The wet landscape approach to oil sands tailings reclamation in the Athabasca Oil Sands region involves creating wetlands from fluid tailings in mined-out pits. We measured time to metamorphosis, thyroid hormone status, and detoxification enzyme (EROD) induction in Wood frog (Lithobates sylvaticus) tadpoles raised on reclaimed oil sands wetlands of different ages [young (≤7 yr) vs. old (>7 yr)] and compared data with tadpoles raised on reference (control) wetlands. Metamorphosis was delayed or never occurred in tadpoles raised in young tailings; those exposed to older tailings developed similarly to those in reference wetlands. Thyroid hormone disruption likely played an important role in the metamorphosis delay as the T3:T4 ratio was lowest in tadpoles raised in young, tailings-affected wetlands. Our findings suggest tailings wetlands become less toxic with age, and that these amphibians will be able to complete their life cycle in tailing wetlands that have sufficiently detoxified with age. - This work provides guidance for reclamation of oil sands tailings and shows the usefulness of frogs and caging studies in environmental toxicology.

  15. Melipona quadrifasciata (Hymenoptera: Apidae) fat body persists through metamorphosis with a few apoptotic cells and an increased autophagy.

    Science.gov (United States)

    Santos, Douglas Elias; Azevedo, Dihego Oliveira; Campos, Lúcio Antônio Oliveira; Zanuncio, José Cola; Serrão, José Eduardo

    2015-03-01

    Fat body, typically comprising trophocytes, provides energy during metamorphosis. The fat body can be renewed once the larval phase is complete or recycled and relocated to form the fat body of the adult insect. This study aims to identify the class of programmed cell death that occurs within the fat body cells during the metamorphosis of the stingless bee Melipona quadrifasciata. Using immunodetection techniques, the fat body of the post-defecating larvae and the white-, pink-, brown-, and black-eyed pupae were tested for cleaved caspase-3 and DNA integrity, followed by ultrastructural analysis and identification of autophagy using RT-PCR for the Atg1 gene. The fat body of M. quadrifasciata showed some apoptotic cells positive for cleaved caspase-3, although without DNA fragmentation. During development, the fat body cells revealed an increased number of mitochondria and free ribosomes, in addition to higher amounts of autophagy Atg1 mRNA, than that of the pupae. The fat body of M. quadrifasciata showed few cells which underwent apoptosis, but there was evidence of increased autophagy at the completion of the larval stage. All together, these data show that some fat body cells persist during metamorphosis in the stingless bee M. quadrifasciata.

  16. Dynamics and regulation of glycolysis-tricarboxylic acid metabolism in the midgut of Spodoptera litura during metamorphosis.

    Science.gov (United States)

    Hu, D; Luo, W; Fan, L F; Liu, F L; Gu, J; Deng, H M; Zhang, C; Huang, L H; Feng, Q L

    2016-04-01

    Significant changes usually take place in the internal metabolism of insects during metamorphosis. The glycolysis-tricarboxylic acid (glycolysis-TCA) pathway is important for energy metabolism. To elucidate its dynamics, the mRNA levels of genes involved in this pathway were examined in the midgut of Spodoptera litura during metamorphosis, and the pyruvate content was quantified. The expression patterns of these genes in response to starvation were examined, and the interaction between protein phosphatase 1 (PP1) and phosphofructokinase (PFK) was studied. The results revealed that the expression or activities of most glycolytic enzymes was down-regulated in prepupae and then recovered in some degree in pupae, and all TCA-related genes were remarkably suppressed in both the prepupae and pupae. Pyruvate was enriched in the pupal midgut. Taken together, these results suggest that insects decrease both glycolysis and TCA in prepupae to save energy and then up-regulate glycolysis but down-regulate TCA in pupae to increase the supply of intermediates for construction of new organs. The expression of all these genes were down-regulated by starvation, indicating that non-feeding during metamorphosis may be a regulator of glycolysis-TCA pathway in the midgut. Importantly, interaction between PP1 and PFK was identified and is suggested to be involved in the regulation of glycolysis. © 2015 The Royal Entomological Society.

  17. Kafka: a metamorfose para os direitos humanos / Kafka: metamorphosis to human rights

    Directory of Open Access Journals (Sweden)

    Leilane Serratine Grubba

    2011-12-01

    Full Text Available Resumo O artigo tem por objeto o Direito e a Literatura. Mais precisamente, objetiva vislumbrar a possibilidade de uma intersecção entre os campos cognitivos do Direito e da Literatura, para compreender a dignidade humana à luz da obra artístico-literária A metamorfose, de Franz Kafka. Assim, em primeiro lugar, o texto centrou-se na possibilidade do diálogo entre as dimensões do Direito e da Arte, essencialmente a Literatura. Como toda grande obra de arte, o livro analisado contém em seu seio uma semente de ruptura e de proposta de movimento criador. Permite aos seus leitores uma abertura de consciência ao novo, a vislumbrar mundos diversos, a pensar transformações dos espaços socioculturais. Assim, no segundo momento, a partir da ideia de que as grandes obras de arte permitem uma análise da sociedade concreta e imanente, o texto centrou-se na investigação da trama literária. Por fim, a partir da história narrada por Kafka e das críticas dos valores da sociedade presentes no texto, principalmente a anulação do sujeito – transformado em animal – partiu-se para a possibilidade de se pensar uma mudança, visando à dignidade humana no mundo contemporâneo, marcado pelo totalitarismo. Palavras-chave: Direito, Literatura, Dignidade Humana, Kafka, Metamorfose Abstract The article focuses on the Law and Literature. More precisely, it aims to glimpse the possibility of an intersection between the cognitive fields of law and literature, in order to understand human dignity in light of the artistic and literary work The Metamorphosis by Franz Kafka. Thus, first, the text centered on the possibility of dialogue between the dimensions of the law of the literature. Like any great work of art, the book analyzed contains in its bosom a seed burst and proposing creative movement. Allows its readers an opening of the new consciousness, a glimpse of different worlds, thinking sociocultural transformations of spaces. Thus, the second time

  18. Threshold Spaces Reconfiguration: On Pinocchio’s Metamorphosis, Between Collodi and Comencini

    Directory of Open Access Journals (Sweden)

    Pier Paolo Argiolas

    2011-06-01

    Full Text Available Metamorphosis is a threshold infringement marking the passage to a new configuration; an intersemiotic translation is also a threshold infringement and a code one. In the comparison between Collodi’s Le avventure di Pinocchio to Luigi Comencini’s 1972 TV adaptation of the same title, and taking into account three further threshold-spaces – intercodical (technical, chronological (historical, and interpretative (ethical-artistic –, this study aims to interpret the filmic adaptation, based on the addition to the original fabula of metamorphic stages which were not in the source-text: the reversible transformations of Pinocchio the puppet in Pinocchio the boy. Recurrent metamorphoses become narrative plot, associated with a moral meaning; denying Collodi’s narrative gratuitousness and dialectics of disorientation/re-collocation, Comencini replaces these interpretative bets with inferential intuitions connected to an ethical code. Furthermore, the comparison of the TV adaptation with the source-text allows for a clarification of some unresolved or ambigous passages of the latter, casting new light right on the metamorphic nature of Collodi’s Pinocchio.

  19. Phylogenetic distribution of extant richness suggests metamorphosis is a key innovation driving diversification in insects.

    Directory of Open Access Journals (Sweden)

    James L Rainford

    Full Text Available Insects and their six-legged relatives (Hexapoda comprise more than half of all described species and dominate terrestrial and freshwater ecosystems. Understanding the macroevolutionary processes generating this richness requires a historical perspective, but the fossil record of hexapods is patchy and incomplete. Dated molecular phylogenies provide an alternative perspective on divergence times and have been combined with birth-death models to infer patterns of diversification across a range of taxonomic groups. Here we generate a dated phylogeny of hexapod families, based on previously published sequence data and literature derived constraints, in order to identify the broad pattern of macroevolutionary changes responsible for the composition of the extant hexapod fauna. The most prominent increase in diversification identified is associated with the origin of complete metamorphosis, confirming this as a key innovation in promoting insect diversity. Subsequent reductions are recovered for several groups previously identified as having a higher fossil diversity during the Mesozoic. In addition, a number of recently derived taxa are found to have radiated following the development of flowering plant (angiosperm floras during the mid-Cretaceous. These results reveal that the composition of the modern hexapod fauna is a product of a key developmental innovation, combined with multiple and varied evolutionary responses to environmental changes from the mid Cretaceous floral transition onward.

  20. Phylogenetic Distribution of Extant Richness Suggests Metamorphosis Is a Key Innovation Driving Diversification in Insects

    Science.gov (United States)

    Rainford, James L.; Hofreiter, Michael; Nicholson, David B.; Mayhew, Peter J.

    2014-01-01

    Insects and their six-legged relatives (Hexapoda) comprise more than half of all described species and dominate terrestrial and freshwater ecosystems. Understanding the macroevolutionary processes generating this richness requires a historical perspective, but the fossil record of hexapods is patchy and incomplete. Dated molecular phylogenies provide an alternative perspective on divergence times and have been combined with birth-death models to infer patterns of diversification across a range of taxonomic groups. Here we generate a dated phylogeny of hexapod families, based on previously published sequence data and literature derived constraints, in order to identify the broad pattern of macroevolutionary changes responsible for the composition of the extant hexapod fauna. The most prominent increase in diversification identified is associated with the origin of complete metamorphosis, confirming this as a key innovation in promoting insect diversity. Subsequent reductions are recovered for several groups previously identified as having a higher fossil diversity during the Mesozoic. In addition, a number of recently derived taxa are found to have radiated following the development of flowering plant (angiosperm) floras during the mid-Cretaceous. These results reveal that the composition of the modern hexapod fauna is a product of a key developmental innovation, combined with multiple and varied evolutionary responses to environmental changes from the mid Cretaceous floral transition onward. PMID:25275450

  1. Triiodothyronine (T3) action on aquatic locomotor behavior during metamorphosis of the bullfrog Rana catesbeiana.

    Science.gov (United States)

    Fernández-Mongil, Marisabel; Venza, Celia J; Rivera, Amelia; Lasalde-Dominicci, José A; Burggren, Warren; Rojas, Legier V

    2009-01-01

    Thyroid hormones--particularly triiodothyronine, T3--play a critical role in the morphological transformations comprising metamorphosis in larval bullfrogs (Rana catesbeiana). Traditional staging criteria for anuran larvae incompletely distinguish physiological and behavioral changes during growth. We therefore first developed a new parameter to describe larval growth, the developmental index (DI), which is simply the ratio between the tail length of the larva and its head diameter. Using the DI we were able to identify two distinct populations classifying the larvae during growth along a continuous linear scale with a cutoff value of DI at 2.8. Classification based on the DI, used in this study, proved an effective complement to existing classifications based on developmental staging into pre- or pro-metamorphic stages. Exposure to T3 in the water induced a rapid (beginning within 5 min) and significant decrease (approximately 20-40%) in locomotor activity, measured as total distance traversed and velocity. The largest decrease occurred in more developed larvae (DI or =2.8). We discuss the significance of the possible role of an apoptotic volume decrease at the level of the neuromuscular junction.

  2. Development of tectal connectivity across metamorphosis in the bullfrog (Rana catesbeiana).

    Science.gov (United States)

    Horowitz, Seth S; Simmons, Andrea Megela

    2010-01-01

    In the bullfrog (Rana catesbeiana), the process of metamorphosis culminates in the appearance of new visual and visuomotor behaviors reflective of the emergence of binocular vision and visually-guided prey capture behaviors as the animal transitions to life on land. Using several different neuroanatomical tracers, we examined the substrates that may underlie these behavioral changes by tracing the afferent and efferent connectivity of the midbrain optic tectum across metamorphic development. Intratectal, tectotoral, tectotegmental, tectobulbar, and tecto-thalamic tracts exhibit similar trajectories of neurobiotin fiber label across the developmental span from early larval tadpoles to adults. Developmental variability was apparent primarily in intensity and distribution of cell and puncta label in target nuclei. Combined injections of cholera toxin subunit β and Phaseolus vulgaris leucoagglutinin consistently label cell bodies, puncta, or fiber segments bilaterally in midbrain targets including the pretectal gray, laminar nucleus of the torus semicircularis, and the nucleus of the medial longitudinal fasciculus. Developmentally stable label was observed bilaterally in medullary targets including the medial vestibular nucleus, lateral vestibular nucleus, and reticular gray, and in forebrain targets including the posterior and ventromedial nuclei of the thalamus. The nucleus isthmi, cerebellum, lateral line nuclei, medial septum, ventral striatum, and medial pallium show more developmentally variable patterns of connectivity. Our results suggest that even during larval development, the optic tectum contains substrates for integration of visual with auditory, vestibular, and somatosensory cues, as well as for guidance of motivated behaviors. Copyright © 2011 S. Karger AG, Basel.

  3. Suitability of golf course ponds for amphibian metamorphosis when bullfrogs are removed.

    Science.gov (United States)

    Boone, Michelle D; Semlitsch, Raymond D; Mosby, Cory

    2008-02-01

    Managing areas designed for human recreation so that they are compatible with natural amphibian populations can reduce the negative impacts of habitat destruction. We examined the potential for amphibians to complete larval development in golf course ponds in the presence or absence of overwintered bullfrog tadpoles (Rana catesbeiana), which are frequently found in permanent, human-made ponds. We reared larval American toads (Bufo americanus), southern leopard frogs (R. sphenocephala), and spotted salamanders (Ambystoma maculatum) with 0 or 5 overwintered bullfrog tadpoles in field enclosures located in ponds on golf courses or in experimental wetlands at a reference site. Survival to metamorphosis of American toads, southern leopard frogs, and spotted salamanders was greater in ponds on golf courses than at reference sites. We attributed this increased survival to low abundance of insect predators in golf course ponds. The presence of overwintered bullfrogs, however, reduced the survival of American toads, southern leopard frogs, and spotted salamanders reared in golf course ponds, indicating that the suitability of the aquatic habitats for these species partly depended on the biotic community present. Our results suggest that ponds in human recreational areas should be managed by maintaining intermediate hydroperiods, which will reduce the presence of bullfrog tadpoles and predators, such as fish, and which may allow native amphibian assemblages to flourish.

  4. Heteropathogenic virulence and phylogeny reveal phased pathogenic metamorphosis in Escherichia coli O2:H6.

    Science.gov (United States)

    Bielaszewska, Martina; Schiller, Roswitha; Lammers, Lydia; Bauwens, Andreas; Fruth, Angelika; Middendorf, Barbara; Schmidt, M Alexander; Tarr, Phillip I; Dobrindt, Ulrich; Karch, Helge; Mellmann, Alexander

    2014-03-01

    Extraintestinal pathogenic and intestinal pathogenic (diarrheagenic) Escherichia coli differ phylogenetically and by virulence profiles. Classic theory teaches simple linear descent in this species, where non-pathogens acquire virulence traits and emerge as pathogens. However, diarrheagenic Shiga toxin-producing E. coli (STEC) O2:H6 not only possess and express virulence factors associated with diarrheagenic and uropathogenic E. coli but also cause diarrhea and urinary tract infections. These organisms are phylogenetically positioned between members of an intestinal pathogenic group (STEC) and extraintestinal pathogenic E. coli. STEC O2:H6 is, therefore, a 'heteropathogen,' and the first such hybrid virulent E. coli identified. The phylogeny of these E. coli and the repertoire of virulence traits they possess compel consideration of an alternate view of pathogen emergence, whereby one pathogroup of E. coli undergoes phased metamorphosis into another. By understanding the evolutionary mechanisms of bacterial pathogens, rational strategies for counteracting their detrimental effects on humans can be developed.

  5. The role of low levels of juvenile hormone Esterase in the metamorphosis of Manduca sexta

    Directory of Open Access Journals (Sweden)

    M.H. Browder

    2001-10-01

    Full Text Available The activity of juvenile hormone esterase (JHE in feeding fifth instar larvae of Manduca sexta increases gradually with larval weight and rises to a peak after larvae pass the critical weight when juvenile hormone secretion ceases. Starvation of larvae of Manduca sexta (L. that had exceeded the critical weight inhibited peak levels of JHE, but did not delay entry into the wandering stage when larvae leave the plant in search of a pupation site. This suggests that peak levels of JHE may not be essential for the normal timing of metamorphosis. Starved larvae pupated normally, indicating the peak of JHE was not necessary for a morphologically normal pupation. Treatments of larvae with the selective JHE inhibitor O-ethyl-S-phenyl phosphoramidothiolate (EPPAT that began immediately after larvae achieved the critical weight (6.0 to 6.5 grams for our strain of Manduca delayed entry into the wandering stage. By contrast, EPPAT treatment of larvae at weights above 8.0g had no effect on the subsequent timing of the onset of wandering. Therefore, although the normal timing of the onset of wandering does not require peak levels of JHE, it requires low to moderate levels of JHE to be present until larvae reach a weight of about 8.0g.

  6. Thematic, conceptual and iconic metamorphosis: the construction of a morphological history epistemological method

    Directory of Open Access Journals (Sweden)

    Maurício de Carvalho Ramos

    2015-12-01

    Full Text Available In this essay, I propose the construction of an epistemological historical method through a morphological perspective. That involves the elaboration of a genetic rational process of conceptualization in which problems, themes and concepts organize in historical expressions increasingly more objective and determinated. Such expressions should be articulated generating a continuum of metamorphosis of a concept or conceptual core. This continuum should be capable of conferring intelligibility for scientific culture units without restrictions of spatial, temporal and conceptual amplitude. The connection of morphological and historical components that I propose is based on the results as well as the method used by Carlo Ginzburg in Myths, emblems and signs, especially in High and low: the theme of forbidden knowledge in the sixteenth and seventeenth centuries. After presenting a characterization of the minimal components of the historical epistemological method, I will start to incorporate elements of Ginsburg’s historical morphology through a dialogue in which I’ll try to understand how the author proceeds methodically and conceptually in his investigation. Finally, through a preliminary study of an alchemical emblem in which Hermes is the central figure, I will make a morphological experiment of application of this procedure to the scope of the scientific culture of chemistry

  7. Effects of cadmium, estradiol-17β and their interaction on gonadal condition and metamorphosis of male and female African clawed frog, Xenopus laevis

    Science.gov (United States)

    Sharma, Bibek; Patino, Reynaldo

    2010-01-01

    To assess interaction effects between cadmium (Cd, a putative xenoestrogen) and estradiol-17?? (E2) on sex differentiation and metamorphosis, Xenopus laevis were exposed to solvent-control (0.005% ethanol), Cd (10 ??g L-1), E2 (1 ??g L-1), or Cd and E2 (Cd + E2) in FETAX medium from fertilization to 75 d postfertilization. Each treatment was applied to four aquaria, each with 30 fertilized eggs. Mortality was recorded and animals were sampled as they completed metamorphosis (Nieuwkoop and Faber stage 66). Gonadal sex of individuals (including tadpoles ???NF stage 55 at day 75) was determined gross-morphologically and used to compute sex ratios. Time course and percent completion of metamorphosis, snout-vent length (SVL), hindlimb length (HLL) and weight were analyzed for each gender separately. Survival rates did not differ among treatments. The E2 and Cd + E2 treatments significantly skewed sex ratios towards females; however, no sex-ratio differences were observed between the control and Cd treatments or between the E2 and Cd + E2 treatments. Time course of metamorphosis was generally delayed and percent completion of metamorphosis was generally reduced in males and females exposed to Cd, E2 or their combination compared to control animals. In males, but not females, the effect of Cd + E2 was greater than that of individual chemicals. Weight at completion of metamorphosis was reduced only in females and only by the Cd + E2 treatment. In conclusion, although Cd at an environmentally relevant concentration did not exhibit direct or indirect feminizing effects in Xenopus tadpoles, the metal and E2 both had similar inhibitory effects on metamorphosis that were of greater magnitude in males than females.

  8. Effects of cadmium, estradiol-17beta and their interaction on gonadal condition and metamorphosis of male and female African clawed frog, Xenopus laevis

    Science.gov (United States)

    Sharma, Bibek; Patino, Reynaldo

    2010-01-01

    To assess interaction effects between cadmium (Cd, a putative xenoestrogen) and estradiol-17beta (E(2)) on sex differentiation and metamorphosis, Xenopus laevis were exposed to solvent-control (0.005% ethanol), Cd (10microgL(-1)), E(2) (1microgL(-1)), or Cd and E(2) (Cd+E(2)) in FETAX medium from fertilization to 75d postfertilization. Each treatment was applied to four aquaria, each with 30 fertilized eggs. Mortality was recorded and animals were sampled as they completed metamorphosis (Nieuwkoop and Faber stage 66). Gonadal sex of individuals (including >or= tadpoles NF stage 55 at day 75) was determined gross-morphologically and used to compute sex ratios. Time course and percent completion of metamorphosis, snout-vent length (SVL), hindlimb length (HLL) and weight were analyzed for each gender separately. Survival rates did not differ among treatments. The E(2) and Cd+E(2) treatments significantly skewed sex ratios towards females; however, no sex-ratio differences were observed between the control and Cd treatments or between the E(2) and Cd+E(2) treatments. Time course of metamorphosis was generally delayed and percent completion of metamorphosis was generally reduced in males and females exposed to Cd, E(2) or their combination compared to control animals. In males, but not females, the effect of Cd+E(2) was greater than that of individual chemicals. Weight at completion of metamorphosis was reduced only in females and only by the Cd+E(2) treatment. In conclusion, although Cd at an environmentally relevant concentration did not exhibit direct or indirect feminizing effects in Xenopus tadpoles, the metal and E(2) both had similar inhibitory effects on metamorphosis that were of greater magnitude in males than females.

  9. Survival and metamorphosis of larval sea lamprey (Petromyzon marinus) residing in Lakes Michigan and Huron near river mouths

    Science.gov (United States)

    Johnson, Nicholas S.; Brenden, Travis O.; Swink, William D.; Lipps, Mathew A.

    2016-01-01

    Although population demographics of larval lampreys in streams have been studied extensively, demographics in lake environments have not. Here, we estimated survival and rates of metamorphosis for larval sea lamprey (Petromyzon marinus) populations residing in the Great Lakes near river mouths (hereafter termed lentic areas). Tagged larvae were stocked and a Bayesian multi-state tag-recovery model was used to investigate population parameters associated with tag recovery, including survival and metamorphosis probabilities. Compared to previous studies of larvae in streams, larval growth in lentic areas was substantially slower (Brody growth coefficient = 0.00132; estimate based on the recovery of six tagged larvae), survival was slightly greater (annual survival = 63%), and the length at which 50% of the larvae would be expected to metamorphose was substantially shorter (126 mm). Stochastic simulations were used to estimate the production of parasitic stage (juvenile) sea lamprey from a hypothetical population of larvae in a lentic environment. Production of juvenile sea lamprey was substantial because, even though larval growth in these environments was slow relative to stream environments, survival was high and length at metamorphosis was less. However, estimated production of juvenile sea lamprey was less for the lentic environment than for similar simulations for river environments where larvae grew faster. In circumstances where the cost to kill a larva with lampricide was equal and control funds are limited, sea lamprey control effort may be best directed toward larvae in streams with fast-growing larvae, because stream-produced larvae will most likely contribute to juvenile sea lamprey populations.

  10. Effects of hydroperiod duration on survival, developmental rate, and size at metamorphosis in boreal chorus frog tadpoles (Pseudacris maculata)

    Science.gov (United States)

    Amburgey, Staci; Funk, W. Chris; Murphy, Melanie; Muths, Erin

    2012-01-01

    Understanding the relationship between climate-driven habitat conditions and survival is key to preserving biodiversity in the face of rapid climate change. Hydroperiod—the length of time water is in a wetland—is a critical limiting habitat variable for amphibians as larvae must metamorphose before ponds dry. Changes in precipitation and temperature patterns are affecting hydroperiod globally, but the impact of these changes on amphibian persistence is poorly understood. We studied the responses of Boreal Chorus Frog (Pseudacris maculata) tadpoles to simulated hydroperiods (i.e., water level reductions) in the laboratory using individuals collected from ponds spanning a range of natural hydroperiods (Colorado Front Range, USA). To assess the effects of experimental hydroperiod reduction, we measured mortality, time to metamorphosis, and size at metamorphosis. We found that tadpoles grew at rates reflecting the hydroperiods of their native ponds, regardless of experimental treatment. Tadpoles from permanent ponds metamorphosed faster than those from ephemeral ponds across all experimental treatments, a pattern which may represent a predation selection gradient or countergradient variation in developmental rates. Size at metamorphosis did not vary across experimental treatments. Mortality was low overall but varied with pond of origin. Our results suggest that adaptation to local hydroperiod and/or predation and temperature conditions is important in P. maculata. Moreover, the lack of a plastic response to reduced hydroperiods suggests that P. maculata may not be able to metamorphose quickly enough to escape drying ponds. These results have important implications for amphibian persistence in ponds predicted to dry more quickly due to rapid climate change.

  11. Transcriptome and quantitative proteome analysis reveals molecular processes associated with larval metamorphosis in the polychaete pseudopolydora vexillosa

    KAUST Repository

    Chandramouli, Kondethimmanahalli

    2013-03-01

    Larval growth of the polychaete worm Pseudopolydora vexillosa involves the formation of segment-specific structures. When larvae attain competency to settle, they discard swimming chaetae and secrete mucus. The larvae build tubes around themselves and metamorphose into benthic juveniles. Understanding the molecular processes, which regulate this complex and unique transition, remains a major challenge because of the limited molecular information available. To improve this situation, we conducted high-throughput RNA sequencing and quantitative proteome analysis of the larval stages of P. vexillosa. Based on gene ontology (GO) analysis, transcripts related to cellular and metabolic processes, binding, and catalytic activities were highly represented during larval-adult transition. Mitogen-activated protein kinase (MAPK), calcium-signaling, Wnt/β-catenin, and notch signaling metabolic pathways were enriched in transcriptome data. Quantitative proteomics identified 107 differentially expressed proteins in three distinct larval stages. Fourteen and 53 proteins exhibited specific differential expression during competency and metamorphosis, respectively. Dramatic up-regulation of proteins involved in signaling, metabolism, and cytoskeleton functions were found during the larval-juvenile transition. Several proteins involved in cell signaling, cytoskeleton and metabolism were up-regulated, whereas proteins related to transcription and oxidative phosphorylation were down-regulated during competency. The integration of high-throughput RNA sequencing and quantitative proteomics allowed a global scale analysis of larval transcripts/proteins associated molecular processes in the metamorphosis of polychaete worms. Further, transcriptomic and proteomic insights provide a new direction to understand the fundamental mechanisms that regulate larval metamorphosis in polychaetes. © 2013 American Chemical Society.

  12. Effects of cadmium on growth, metamorphosis and gonadal sex differentiation in tadpoles of the African clawed frog, Xenopus laevis

    Science.gov (United States)

    Sharma, Bibek; Patino, Reynaldo

    2009-01-01

    Xenopus laevis larvae were exposed to cadmium (Cd) at 0, 1, 8. 85 or 860 mu g L(-1) in FETAX medium from 0 to 86 d postfertilization. Premetamorphic tadpoles were sampled on day 3 1; pre and prometamorphic tadpoles on day 49; and frogs (NF stage 66) between days 50 and 86. Survival, snout-vent length (SVL), tail length, total length, hindlimb length (HLL), initiation of metamorphic climax, size at and completion of metamorphosis, and gonadal condition and sex ratio (assessed histologically) were determined. Survival was unaffected by Cd until day 49, but increased mortality was observed after day 49 at 860 mu g Cd L(-1). On day 31, when tadpoles were in early premetamorphosis, inhibitory effects on tadpole growth were observed only at 860 mu g Cd L(-1). On day 49, when most tadpoles where in late premetamorphosis/early prometamorphosis, reductions in SVL, HLL and total length were observed at 8 and 860 but not 85 mu g L(-1), thus creating a U-shaped size distribution at 0-85 mu g Cd L(-1). However, this U-shaped size pattern was not evident in postmetamorphic individuals. In fact, frog size at completion of metamorphosis was slightly smaller at 85 mu g Cd L(-1) relative to control animals. These observations confirmed a recent report of a Cd concentration-dependent bimodal growth pattern in late-premetamorphic Xenopus tadpoles, but also showed that growth responses to varying Cd concentrations change with development. The fraction of animals initiating or completing metamorphosis during days 50-86 was reduced in a Cd concentration-dependent manner. Testicular histology and population sex ratios were unaffected by Cd suggesting that, unlike mammals, Cd is not strongly estrogenic in Xenopus tadpoles.

  13. 2D Gel-Based Multiplexed Proteomic Analysis during Larval Development and Metamorphosis of the Biofouling Polychaete Tubeworm Hydroides elegans

    KAUST Repository

    Zhang, Yu

    2010-09-03

    Larval settlement and metamorphosis of a common biofouling polychaete worm, Hydroides elegans, involve remarkable structural and physiological changes during this pelagic to sessile habitat shift. The endogenous protein molecules and post-translational modifications that drive this larval transition process are not only of interest to ecologists but also to the antifouling paint industry, which aims to control the settlement of this biofouling species on man-made structures (e.g., ship hulls). On the basis of our recent proteomic studies, we hypothesize that rapid larval settlement of H. elegans could be mediated through changes in phosphorylation status of proteins rather than extensive de novo synthesis of proteins. To test this hypothesis, 2D gel-based multiplexed proteomics technology was used to monitor the changes in protein expression and phosphorylation status during larval development and metamorphosis of H. elegans. The protein expression profiles of larvae before and after they reached competency to attach and metamorphose were similar in terms of major proteins, but the percentage of phosphorylated proteins increased from 41% to 49% after competency. Notably, both the protein and phosphoprotein profiles of the metamorphosed individuals (adult) were distinctly different from that of the larvae, with only 40% of the proteins phosphorylated in the adult stage. The intensity ratio of all phosphoprotein spots to all total protein spots was also the highest in the competent larval stage. Overall, our results indicated that the level of protein phosphorylation might play a crucial role in the initiation of larval settlement and metamorphosis. © 2010 American Chemical Society.

  14. RNA interference of a trehalose-6-phosphate synthase gene reveals its roles during larval-pupal metamorphosis in Bactrocera minax (Diptera: Tephritidae).

    Science.gov (United States)

    Xiong, Ke-Cai; Wang, Jia; Li, Jia-Hao; Deng, Yu-Qing; Pu, Po; Fan, Huan; Liu, Ying-Hong

    2016-01-01

    Trehalose is the major blood sugar in insects, which plays a crucial role as an instant source of energy and the starting substrate for chitin biosynthesis. In insects, trehalose is synthesized by catalysis of an important enzyme, trehalose-6-phosphate synthase (TPS). In the present study, a trehalose-6-phosphate synthase gene from Bactrocera minax (BmTPS) was cloned and characterized. BmTPS contained an open reading frame of 2445 nucleotides encoding a protein of 814 amino acids with a predicted molecular weight of 92.05kDa. BmTPS was detectable in all developmental stages of Bactrocera minax and expressed higher in the final- (third-) instar larvae. Tissue-specific expression patterns of BmTPS showed that it was mainly expressed in the fat body. The 20-hydroxyecdysone (20E) induced the expression of BmTPS and three genes in the chitin biosynthesis pathway. Moreover, injection of double-stranded RNA into third-instar larvae successfully silenced the transcription of BmTPS in B. minax, and thereby decreased the activity of TPS and trehalose content. Additionally, silencing of BmTPS inhibited the expression of three key genes in the chitin biosynthesis pathway and exhibited 52% death and abnormal phenotypes. The findings demonstrate that BmTPS is indispensable for larval-pupal metamorphosis. Besides, the establishment of RNAi experimental system in B. minax would lay a solid foundation for further investigation of molecular biology and physiology of this pest. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Molecular cloning of a preprohormone from sea anemones containing numerous copies of a metamorphosis-inducing neuropeptide: a likely role for dipeptidyl aminopeptidase in neuropeptide precursor processing

    DEFF Research Database (Denmark)

    Leviev, I; Grimmelikhuijzen, C J

    1995-01-01

    the precursor protein for this metamorphosis-inducing neuropeptide from sea anemones. The precursor protein is 514-amino acid residues long and contains 10 copies of the immature, authentic neuropeptide (Gln-Gln-Pro-Gly-Leu-Trp-Gly). All neuropeptide copies are preceded by Xaa-Pro or Xaa-Ala sequences...... a polyp, a medusa, and a planula larva stage. Recently, a neuropeptide, sea anemones that induces metamorphosis in a hydroid planula larva to become a hydropolyp [Leitz, T., Morand, K. & Mann, M. (1994) Dev. Biol. 163, 440-446]. Here, we have cloned...

  16. Geographic variation in host fish use and larval metamorphosis for the endangered dwarf wedgemussel

    Science.gov (United States)

    White, Barbara (St. John); Ferreri, C. Paola; Lellis, William A.; Wicklow, Barry J.; Cole, Jeffrey C.

    2017-01-01

    Host fishes play a crucial role in survival and dispersal of freshwater mussels (Unionoida), particularly rare unionids at conservation risk. Intraspecific variation in host use is not well understood for many mussels, including the endangered dwarf wedgemussel (Alasmidonta heterodon) in the USA.Host suitability of 33 fish species for dwarf wedgemussel glochidia (larvae) from the Delaware and Connecticut river basins was tested in laboratory experiments over 9 years. Relative suitability of three different populations of a single host fish, the tessellated darter (Etheostoma olmstedi), from locations in the Connecticut, Delaware, and Susquehanna river basins, was also tested.Connecticut River basin A. heterodon metamorphosed into juvenile mussels on tessellated darter, slimy sculpin (Cottus cognatus), and Atlantic salmon (Salmo salar) parr. Delaware River basin mussels metamorphosed using these three species, as well as brown trout (Salmo trutta), banded killifish (Fundulus diaphanus), mottled sculpin (Cottus bairdii), striped bass (Morone saxatilis), and shield darter (Percina peltata). Atlantic salmon, striped bass, and sculpins were highly effective hosts, frequently generating 5+ juveniles per fish (JPF) and metamorphosis success (MS; proportion of attaching larvae that successfully metamorphose) ≥ 0.4, and producing juveniles in repeated trials.In experiments on tessellated darters, mean JPF and MS values decreased as isolation between the mussel source (Connecticut River) and each fish source increased; mean JPF = 10.45, 6.85, 4.14, and mean MS = 0.50, 0.41, and 0.34 in Connecticut, Delaware, and Susquehanna river darters, respectively. Host suitability of individual darters was highly variable (JPF = 2–11; MS = 0.20–1.0).The results show that mussel–host fish compatibility in A. heterodon differs among Atlantic coastal rivers, and suggest that hosts including anadromous Atlantic salmon and striped bass may help sustain A. heterodon in parts of

  17. Heritage of the romantic philosophy in post-Linnaean botany Reichenbach's reception of Goethe's metamorphosis of plants as a methodological and philosophical framework.

    Science.gov (United States)

    Robin, Nicolas

    2011-01-01

    This paper demonstrates the importance of the reception and development of Goethe's metamorphosis of plants as a methodological and philosophical framework in the history of botanical theories. It proposes a focus on the textbooks written by the German botanist Ludwig Reichenbach and his first attempt to use Goethe's idea of metamorphosis of plants as fundamental to his natural system of plants published under the title 'Botany for Women', in German Botanik für Damen (1828). In this book, Reichenbach paid particular attention to Goethe's sensitive views on the essence of nature; he regarded Goethe's idea of metamorphosis in the plant kingdom as an ideal model to interpret connections of natural phenomena, in particular as a conceptual frame for a natural system. Furthermore, he aimed to develop the philosophical statement of the metamorphosis, in which he called for nature-philosophical conceptions in order to materialize his representation of plant "affinities," and of a kind of "ontogeny" of the whole plant kingdom. This paper demonstrates that, between speculative views and empirical attempts, the extent to which Reichenbach actually belonged to a new "school" of thought, which left its mark on the history and philosophy of botany.

  18. Renaissance Epyllions: A Comparative Reading of Christopher Marlowe's "Hero and Leander," Thomas Lodge's "Scylla's Metamorphosis" and Francis Beaumont's "Salmacis and Hermaphroditus"

    Science.gov (United States)

    Mahmoudi, Yazdan

    2016-01-01

    The present paper is supposed to compare and contrast three of these masterpieces written the Renaissance period. The epyllions under study are Christopher Marlowe's "Hero and Leander," Thomas Lodge's "Scylla's Metamorphosis" and Francis Beaumont's "Salmacis and Hermaphroditus." Bush believes that "the influence…

  19. [Light and electron microscopy analysis of the differentiation of oropharyngeal epithelium in Salamandra salamandra (L.) during metamorphosis (Urodela:Salamandridae)].

    Science.gov (United States)

    Clemen, G

    1985-01-01

    During metamorphosis the oropharyngeal-epithelium of Salamandra salamandra consists of cells partly with features typical for larvae partly with these characteristic for metamorphosed animals. In the stratum intermedium cells which in larvae develop to secreting non-ciliated pavement cells become precursors of ciliated cells. During this process mucus granulus were discharged and cells develop cilia. Cells of deepe layers stop the production of mucus granules; those granules, which are already present, disintegrate. Furthermore, new types of goblet cells (type 2 and 3 according to Clemen, 1984) arise. Goblet cells of older larvae (typ 1) are to be found nearly unchanged in metamorphosed animals. Older goblet cells degenerate. In the stratum superficiale during transformation of pavement cells to ciliated cells discharge of mucus and ciliogenesis run parallely. Some of the pavement cells, however, degenerate. The stratum basale remains unaltered.

  20. Distribution of BDE-99 and effects on metamorphosis of BDE-99 and -47 after oral exposure in Xenopus tropicalis

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Gunnar [Division of Pathology, Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7028, SE-750 07 Uppsala (Sweden) and Centre for Reproductive Biology in Uppsala (CRU), P.O. Box 7054, SE-750 07 Uppsala (Sweden)]. E-mail: gunnar.carlsson@bvf.slu.se; Kulkarni, Pushkar [Division of Pathology, Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7028, SE-750 07 Uppsala (Sweden); Larsson, Pia [Division of Pathology, Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7028, SE-750 07 Uppsala (Sweden); Norrgren, Leif [Division of Pathology, Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, P.O. Box 7028, SE-750 07 Uppsala (Sweden); Centre for Reproductive Biology in Uppsala (CRU), P.O. Box 7054, SE-750 07 Uppsala (Sweden)

    2007-08-15

    The high concentrations of polybrominated diphenylethers (PBDEs) in the environment have raised the need for generating more information about the impact of these substances on animals. To study the distribution of {sup 14}C-labelled 2,2',4,4',5-pentabromodiphenyl ether ({sup 14}C-BDE-99) in Xenopus tropicalis (West African clawed frog) {sup 14}C-BDE-99 was administered by dietary exposure to tadpoles at stage 54 or to juvenile frogs at stage 66. Whole-body autoradiography and liquid scintillation counting were used to examine the distribution of the substance at different survival times. Further, X. tropicalis tadpoles were dietarily exposed to the PBDE congeners BDE-47 and BDE-99 to study the effects on metamorphosis process. Measurements like body weight, body length, hind limb length and developmental stage as well as histological measurements on thyroid glands were performed after 14 days of exposure. Autoradiograms revealed high concentrations and long term retention of {sup 14}C-BDE-99 in adipose tissue and melanin in frogs exposed both as tadpoles and juveniles. Further, a difference in uptake was recorded between the exposures at stages 54 and 66, implying that the juvenile frogs have higher uptake and more prolonged retention of the chemical than the tadpoles. Hind limb length was reduced in tadpoles dietarily exposed to 1 mg/g feed of both BDE congeners. This was associated with reduced body weight and body length for BDE-47, suggesting general toxicity. Tadpoles exposed to BDE-99 also showed lower developmental stage but no effects on body weight or body length, suggesting possible thyroid hormone disruption. Higher concentrations of both congeners caused increased mortality. Thus, it can be concluded that in the present study, BDE-99 was retained for a longer period in the juvenile frogs than in metamorphosing tadpoles and that BDE-99 had an impact on X. tropicalis metamorphosis that might be of thyroid disrupting origin.

  1. Distribution of BDE-99 and effects on metamorphosis of BDE-99 and -47 after oral exposure in Xenopus tropicalis

    International Nuclear Information System (INIS)

    Carlsson, Gunnar; Kulkarni, Pushkar; Larsson, Pia; Norrgren, Leif

    2007-01-01

    The high concentrations of polybrominated diphenylethers (PBDEs) in the environment have raised the need for generating more information about the impact of these substances on animals. To study the distribution of 14 C-labelled 2,2',4,4',5-pentabromodiphenyl ether ( 14 C-BDE-99) in Xenopus tropicalis (West African clawed frog) 14 C-BDE-99 was administered by dietary exposure to tadpoles at stage 54 or to juvenile frogs at stage 66. Whole-body autoradiography and liquid scintillation counting were used to examine the distribution of the substance at different survival times. Further, X. tropicalis tadpoles were dietarily exposed to the PBDE congeners BDE-47 and BDE-99 to study the effects on metamorphosis process. Measurements like body weight, body length, hind limb length and developmental stage as well as histological measurements on thyroid glands were performed after 14 days of exposure. Autoradiograms revealed high concentrations and long term retention of 14 C-BDE-99 in adipose tissue and melanin in frogs exposed both as tadpoles and juveniles. Further, a difference in uptake was recorded between the exposures at stages 54 and 66, implying that the juvenile frogs have higher uptake and more prolonged retention of the chemical than the tadpoles. Hind limb length was reduced in tadpoles dietarily exposed to 1 mg/g feed of both BDE congeners. This was associated with reduced body weight and body length for BDE-47, suggesting general toxicity. Tadpoles exposed to BDE-99 also showed lower developmental stage but no effects on body weight or body length, suggesting possible thyroid hormone disruption. Higher concentrations of both congeners caused increased mortality. Thus, it can be concluded that in the present study, BDE-99 was retained for a longer period in the juvenile frogs than in metamorphosing tadpoles and that BDE-99 had an impact on X. tropicalis metamorphosis that might be of thyroid disrupting origin

  2. RNAi-mediated knockdown of SPOOK reduces ecdysteroid titers and causes precocious metamorphosis in the desert locust Schistocerca gregaria.

    Science.gov (United States)

    Sugahara, Ryohei; Tanaka, Seiji; Shiotsuki, Takahiro

    2017-09-01

    The Halloween gene SPOOK (SPO) is involved in the production of the active metabolite of ecdysteroid, 20-hydroxyecdysone (20E), in insects. A previous study showed that RNAi-mediated knockdown of SPO in Schistocerca gregaria last instar nymphs markedly reduced the hemolymph 20E titer, but did not affect metamorphosis. In the present study, the effects of SPO interference on development were re-examined in this locust. Injections of SPO double-stranded RNA (dsSPO) into nymphs at mid and late instars significantly delayed nymphal development and interfered with molting. The 20E levels of dsSPO-treated nymphs were generally low, with a delayed, small peak, suggesting that disturbance of the 20E levels caused the above developmental abnormalities. A small proportion of the dsSPO-injected nymphs metamorphosed precociously, producing adults and adultoids. Precocious adults were characterized by small body size, short wings with abbreviated venation, and normal reproductive activity. Fourth instar nymphs that precociously metamorphosed at the following instar exhibited temporal expression patterns of ecdysone-induced protein 93F and the juvenile hormone (JH) early-inducible gene Krüppel homolog 1 similar to those observed at the last instar in normal nymphs. Adultoids displayed mating behavior and adultoid females developed eggs, but never laid eggs. JH injection around the expected time of the 20E peak in the dsSPO-injected nymphs completely inhibited the appearance of adultoids, suggesting that appearance of adultoids might be due to a reduced titer of JH rather than of 20E. These results suggest that SPO plays an important role in controlling morphogenesis, metamorphosis, and reproduction in S. gregaria. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Mitochondrial iron supply is required for the developmental pulse of ecdysone biosynthesis that initiates metamorphosis in Drosophila melanogaster.

    Science.gov (United States)

    Llorens, Jose V; Metzendorf, Christoph; Missirlis, Fanis; Lind, Maria I

    2015-12-01

    Synthesis of ecdysone, the key hormone that signals the termination of larval growth and the initiation of metamorphosis in insects, is carried out in the prothoracic gland by an array of iron-containing cytochrome P450s, encoded by the halloween genes. Interference, either with iron-sulfur cluster biogenesis in the prothoracic gland or with the ferredoxins that supply electrons for steroidogenesis, causes a block in ecdysone synthesis and developmental arrest in the third instar larval stage. Here we show that mutants in Drosophila mitoferrin (dmfrn), the gene encoding a mitochondrial carrier protein implicated in mitochondrial iron import, fail to grow and initiate metamorphosis under dietary iron depletion or when ferritin function is partially compromised. In mutant dmfrn larvae reared under iron replete conditions, the expression of halloween genes is increased and 20-hydroxyecdysone (20E), the active form of ecdysone, is synthesized. In contrast, addition of an iron chelator to the diet of mutant dmfrn larvae disrupts 20E synthesis. Dietary addition of 20E has little effect on the growth defects, but enables approximately one-third of the iron-deprived dmfrn larvae to successfully turn into pupae and, in a smaller percentage, into adults. This partial rescue is not observed with dietary supply of ecdysone's precursor 7-dehydrocholesterol, a precursor in the ecdysone biosynthetic pathway. The findings reported here support the notion that a physiological supply of mitochondrial iron for the synthesis of iron-sulfur clusters and heme is required in the prothoracic glands of insect larvae for steroidogenesis. Furthermore, mitochondrial iron is also essential for normal larval growth.

  4. Larval development and post-settlement metamorphosis of the barnacle Balanus albicostatus Pilsbry and the serpulid polychaete Pomatoleios kraussii Baird: Impact of a commonly used antifouling biocide, Irgarol 1051

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; Desai, D.V.; Shirayama, Y.

    Nauplii that survived to the cyprid instar stage when reared in the presence of Irgarol 1051 showed prolonged instar and total naupliar duration when compared to the controls The post-settlement metamorphosis of cyprids significantly varied with Irgarol...

  5. Significance of biofilm proteins in modulating cyprid metamorphosis of Balanus amphitrite (Cirripedia: Thoracica)

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, L.; KrishnaKumar, S.

    and cleaned using nylon brush to remove all the epiphytes. Equal weight/volume of deionized, RO pure water was used to crush the adults using a pestle and mortar. Subsequently, the mixture was centrifuged at 12 000 x g for 5 min. The supernatant... Marine Biology and Ecology, 313, 191-209. Desai D.V., Anil A.C. (2004) The impact of food type, temperature and starvation on the larval development of Balanus amphitrite Darwin (Cirripedia: Thoracica). Journal of Experimental Marine Biology...

  6. The effects of dexamethasone (DXM) and vitamin A on the growth and metamorphosis of gamma irradiated, thyroxine induced Bufo melanostictus tadpoles

    International Nuclear Information System (INIS)

    Ahmad, M.; Haider, N.; Siddiqui, R.Q.R.

    1980-01-01

    This study deals with the effects of vitamin A and dexamethasone (DXM) on the metamorphosis of irradiated tadpoles. Results indicate that hypervitaminosis A depresses the metamorphosing action of thyroxine for several days. On the contrary, dexamethasone accelerates the action of exogenous thyroxine on tadpoles. Thus present data suggest that DXM supresses STH synthesis and promotes TSH secretion. Moreover, muscle appears to be its target tissue and DXM seems to promote the proteolytic digestion of the larval tail. (author)

  7. Fish larval recruitment to reefs is a thyroid hormone-mediated metamorphosis sensitive to the pesticide chlorpyrifos

    Science.gov (United States)

    Lambert, Anne; François, Loïc; Barth, Paul; Gillet, Benjamin; Hughes, Sandrine; Piganeau, Gwenaël; Leulier, Francois; Viriot, Laurent

    2017-01-01

    Larval recruitment, the transition of pelagic larvae into reef-associated juveniles, is a critical step for the resilience of marine fish populations but its molecular control is unknown. Here, we investigate whether thyroid-hormones (TH) and their receptors (TR) coordinate the larval recruitment of the coral-reef-fish Acanthurus triostegus. We demonstrate an increase of TH-levels and TR-expressions in pelagic-larvae, followed by a decrease in recruiting juveniles. We generalize these observations in four other coral reef-fish species. Treatments with TH or TR-antagonist, as well as relocation to the open-ocean, disturb A. triostegus larvae transformation and grazing activity. Likewise, chlorpyrifos, a pesticide often encountered in coral-reefs, impairs A. triostegus TH-levels, transformation, and grazing activity, hence diminishing this herbivore’s ability to control the spread of reef-algae. Larval recruitment therefore corresponds to a TH-controlled metamorphosis, sensitive to endocrine disruption. This provides a framework to understand how larval recruitment, critical to reef-ecosystems maintenance, is altered by anthropogenic stressors. PMID:29083300

  8. Effects of trophic level and metamorphosis on discrimination of hydrogen isotopes in a plant-herbivore system

    Science.gov (United States)

    Peters, Jacob M.; Wolf, Nathan; Stricker, Craig A.; Collier, Timothy R.; Martinez del Rio, Carlos

    2012-01-01

    The use of stable isotopes in ecological studies requires that we know the magnitude of discrimination factors between consumer and element sources. The causes of variation in discrimination factors for carbon and nitrogen have been relatively well studied. In contrast, the discrimination factors for hydrogen have rarely been measured. We grew cabbage looper caterpillars (Trichoplusia ni) on cabbage (Brassica oleracea) plants irrigated with four treatments of deuterium-enriched water (δD = -131, -88, -48, and -2‰, respectively), allowing some of them to reach adulthood as moths. Tissue δD values of plants, caterpillars, and moths were linearly correlated with the isotopic composition of irrigation water. However, the slope of these relationships was less than 1, and hence, discrimination factors depended on the δD value of irrigation water. We hypothesize that this dependence is an artifact of growing plants in an environment with a common atmospheric δD value. Both caterpillars and moths were significantly enriched in deuterium relative to plants by ~45‰ and 23‰ respectively, but the moths had lower tissue to plant discrimination factors than did the caterpillars. If the trophic enrichment documented here is universal, δD values must be accounted for in geographic assignment studies. The isotopic value of carbon was transferred more or less faithfully across trophic levels, but δ15N values increased from plants to insects and we observed significant non-trophic 15N enrichment in the metamorphosis from larvae to adult.

  9. Effects of trophic level and metamorphosis on discrimination of hydrogen isotopes in a plant-herbivore system.

    Directory of Open Access Journals (Sweden)

    Jacob M Peters

    Full Text Available The use of stable isotopes in ecological studies requires that we know the magnitude of discrimination factors between consumer and element sources. The causes of variation in discrimination factors for carbon and nitrogen have been relatively well studied. In contrast, the discrimination factors for hydrogen have rarely been measured. We grew cabbage looper caterpillars (Trichoplusia ni on cabbage (Brassica oleracea plants irrigated with four treatments of deuterium-enriched water (δD = -131, -88, -48, and -2‰, respectively, allowing some of them to reach adulthood as moths. Tissue δD values of plants, caterpillars, and moths were linearly correlated with the isotopic composition of irrigation water. However, the slope of these relationships was less than 1, and hence, discrimination factors depended on the δD value of irrigation water. We hypothesize that this dependence is an artifact of growing plants in an environment with a common atmospheric δD value. Both caterpillars and moths were significantly enriched in deuterium relative to plants by ∼45‰ and 23‰ respectively, but the moths had lower tissue to plant discrimination factors than did the caterpillars. If the trophic enrichment documented here is universal, δD values must be accounted for in geographic assignment studies. The isotopic value of carbon was transferred more or less faithfully across trophic levels, but δ(15N values increased from plants to insects and we observed significant non-trophic (15N enrichment in the metamorphosis from larvae to adult.

  10. Differential Survival among Batches of Atlantic Cod (Gadus morhua L. from Fertilisation through to Post-Metamorphosis.

    Directory of Open Access Journals (Sweden)

    Petra E Petersen

    Full Text Available Aquaculture production of cod has decreased from over 20,000 tonnes in 2009 to less than 2,000 tonnes in 2014 and the industry faces many challenges, one of which is high and unpredictably variable mortality rates in the early life stages. Hence, full-cycle farming with hatchery produced juveniles is still considered unprofitable compared to fisheries and on-growing of wild cod. In the present study, potential batch differences in progeny survival of wild-caught, hatchery-spawned Faroe Bank cod (Gadus morhua L. were investigated at two defined periods during early life history; i the embryo stage (60 day degrees post fertilisation and ii the fry stage (110 days post hatch, post metamorphosis. The fry stage experiment was conducted in three replicates (N = 300 per replicate, and a panel of three polymorphic microsatellite markers was used for parental analysis. Mean survival rate at the embryo stage was 69% (± 20% SD. Survival was positively associated with egg diameter (P < 0.01, explaining 90% of the variation in egg survival rates. The data were too scarce to conclude either way concerning a possible correlation between survival rates between the two periods (P < 0.10. Offspring from three batches (from a total of eight dominated in the fry stage, contributing over 90% of the progeny, and results were consistent over all three replicate tanks. The skewed batch representation observed may be of relevance to the effective management of selective breeding programmes for cod.

  11. Drosophila motor neuron retraction during metamorphosis is mediated by inputs from TGF-β/BMP signaling and orphan nuclear receptors.

    Directory of Open Access Journals (Sweden)

    Ana Boulanger

    Full Text Available Larval motor neurons remodel during Drosophila neuro-muscular junction dismantling at metamorphosis. In this study, we describe the motor neuron retraction as opposed to degeneration based on the early disappearance of β-Spectrin and the continuing presence of Tubulin. By blocking cell dynamics with a dominant-negative form of Dynamin, we show that phagocytes have a key role in this process. Importantly, we show the presence of peripheral glial cells close to the neuro-muscular junction that retracts before the motor neuron. We show also that in muscle, expression of EcR-B1 encoding the steroid hormone receptor required for postsynaptic dismantling, is under the control of the ftz-f1/Hr39 orphan nuclear receptor pathway but not the TGF-β signaling pathway. In the motor neuron, activation of EcR-B1 expression by the two parallel pathways (TGF-β signaling and nuclear receptor triggers axon retraction. We propose that a signal from a TGF-β family ligand is produced by the dismantling muscle (postsynapse compartment and received by the motor neuron (presynaptic compartment resulting in motor neuron retraction. The requirement of the two pathways in the motor neuron provides a molecular explanation for the instructive role of the postsynapse degradation on motor neuron retraction. This mechanism insures the temporality of the two processes and prevents motor neuron pruning before postsynaptic degradation.

  12. Russian comparative embryology takes form: a conceptual metamorphosis toward "evo-devo".

    Science.gov (United States)

    Mikhailov, Alexander T

    2012-01-01

    This essay recapitulates major paths followed by the Russian tradition of what we refer to today as evolutionary developmental biology ("evo-devo"). The article addresses several questions regarding the conceptual history of evolutionary embryological thought in its particularly Russian perspective: (1) the assertion by the St. Petersburg academician Wolff regarding the possible connections between environmental modifications during morphogenesis and the "transformation" of species, (2) the discovery of shared "principles" underlying animal development by von Baer, (3) the experimental expression of Baer's principles by Kowalevsky and Mechnikoff, (4) Severtsov's theory of phylembryogenesis, (5) Filatov's approach to the study of evolution using comparative "developmental mechanics", and (6) Shmalgausen's concept of "stabilizing" selection as an attempt to elucidate the evolution of developmental mechanisms. The focus on comparative evolutionary embryology, which was established by Kowalevsky and Mechnikoff, still continues to be popular in present-day "evo-devo" research in Russia. © 2012 Wiley Periodicals, Inc.

  13. Quantum top secret. The solution of the quantum puzzle. Metamorphosis of a picture of world

    International Nuclear Information System (INIS)

    Wingert, M.

    2008-01-01

    Many physicists believe that because of unexplained causes, which must anyway be concerned with the quantum puzzle and the mysterious consciousness, it would be no more possible to understand the real structure of the reality - this subtle smiling of the nature, which irritates the physicists since 100 years and the disturbed the theoretical physics so much that they threw the towel. Since nature is considered as absurd, strange, and crazy - and quantum theory as very complicated. But in reality the basic experiments are of a touching simplicity, which seems only completely unintelligible in the picture of world of mechanics. For these experiments show that the concept of body of mechanics and the body conceptions of the thinking cannot at all match the structure of nature. If this is objectively taken notice of without doubting on the existence of a reality, the experiments show the real, unveiled face of the nature. Light and matter must then consist of fields, which can themselves divide by non-mechanical way, so with wholeness, comparable only with cell division and branching processes in biology. Either it is completely crazy - or the only logic interpretation, which hitherto only no physicist risked to think. For these experiments disprove the atom and elementary-particle hypothesis, the picture of world of mechanics, and also the quantum-mechanical interpretation - and indeed uniquely. This knowledge could break the Gordian knot, solve the quantum puzzle, and also give away the secret of the thinking spirit

  14. Larval settlement and spat recovery rates of the oyster Crassostrea brasiliana (Lamarck, 1819) using different systems to induce metamorphosis.

    Science.gov (United States)

    Silveira, R C; Silva, F C; Gomes, C H M; Ferreira, J F; Melo, C M R

    2011-05-01

    This study aimed at the assessment, in the laboratory, of the larval settlement and spat recovery rates of oysters of the species Crassostrea brasiliana using plastic collectors, epinephrine (C9H13NO3 C4H6O6) and shell powder in settlement tanks. Polypropylene was used attached to bamboo frames. The material was chosen due to its pliability--that favours the spat detachment. Two experiments were carried out; the first between February and April 2008, and the second between November and December 2008 at the Marine Mussel Laboratory of Santa Catarina Federal University (Laboratório de Moluscos Marinhos da Universidade Federal de Santa Catarina). In the first experiment, the scratched plastic collectors were tested consorting them with shell powder; on the second, the plastic collectors were tested consorted with shell powder, only shell powder and epinephrine as the metamorphosis stimulator. The quantification was carried out of the larvae settled in the plastic collectors, and of the recovery and integrity of the spats after their detachment. The first experiment has shown a recovery rate of 48.83% of the spats in comparison with the D larvae used. From this percentage, 4.9% settled in the plastic collectors and 43.93% in shell powder. The second experiment revealed 55.78% regarding the settled spats in comparison with the total of larvae used (using epinephrine), 78.62% in the treatment with the collector plus shell powder and 58.33% in the treatment only with shell powder. Thus, the use of the collector plus shell powder resulted in a greater spat recovery when compared to the other treatments.

  15. Fitness Effects of Chlorpyrifos in the Damselfly Enallagma cyathigerum Strongly Depend upon Temperature and Food Level and Can Bridge Metamorphosis.

    Directory of Open Access Journals (Sweden)

    Lizanne Janssens

    Full Text Available Interactions between pollutants and suboptimal environmental conditions can have severe consequences for the toxicity of pollutants, yet are still poorly understood. To identify patterns across environmental conditions and across fitness-related variables we exposed Enallagma cyathigerum damselfly larvae to the pesticide chlorpyrifos at two food levels or at two temperatures and quantified four fitness-related variables (larval survival, development time, mass at emergence and adult cold resistance. Food level and temperature did not affect survival in the absence of the pesticide, yet the pesticide reduced survival only at the high temperature. Animals reacted to the pesticide by accelerating their development but only at the high food level and at the low temperature; at the low food level, however, pesticide exposure resulted in a slower development. Chlorpyrifos exposure resulted in smaller adults except in animals reared at the high food level. Animals reared at the low food level and at the low temperature had a higher cold resistance which was not affected by the pesticide. In summary our study highlight that combined effects of exposure to chlorpyrifos and the two environmental conditions (i were mostly interactive and sometimes even reversed in comparison with the effect of the environmental condition in isolation, (ii strongly differed depending on the fitness-related variable under study, (iii were not always predictable based on the effect of the environmental condition in isolation, and (iv bridged metamorphosis depending on which environmental condition was combined with the pesticide thereby potentially carrying over from aquatic to terrestrial ecosystems. These findings are relevant when extrapolating results of laboratory tests done under ideal environmental conditions to natural communities.

  16. Masks and metamorphosis of female creativity - Doll by Milena Pavlović Barili

    Directory of Open Access Journals (Sweden)

    Jovičić Petrija

    2015-01-01

    Full Text Available The paper analyzes the painting Doll by Milena Pavlović Barili in the context of anthropology, fine arts and feminist studies. Phantasmic figures in the painting are discussed as symbols of transformation, gender and sexual identity tittuping, and their scenic “masking” as a platform for finding comprehensive creative personality, ironizing biological “specialization of females”. The name Doll suggests pondering about gender roles, because a doll is a must toy for girls, thus preparing them for motherhood and housework; in addition, it also carries a status of (beautiful an object manipulated in men's world. Attaching a male head onto the ”Doll’s” body can be seen as a form of revolt and struggle to overcome inferior position. On one hand, the male head, with its size and audacity pushes into the background body /object doll-girl, while on the other hand, the head as a symbol of "men’s intelligence" provides subjectivity to the "doll" and the desired superiority in the world of male dominance. The Doll, with the characteristics of male power, simultaneously conceals and highlights the vulnerability and social marginalization of femininity. At the same time, in the desire for self-realization, the doll can fall into the trap of imitating men-- the struggle to gain power, but also could mean a recognition of one’s own/ female inadequacy and inferior position. However, the male’s naked body, deprived of the face and hands - and hence subjectivity and activity -is turned into a (beautiful object and pushed into the background, emphasizing the ambiguity of the relationship of "male" and "female" position and hence opening up the possibility of various interpretations of the painting within the theory of gender, sexuality and creativity. [Projekat Ministarstva nauke Republike Srbije, br. 47016: Interdisciplinarno istraživanje kulturnog i jezičkog nasleđa Srbije. Izrada multimedijalnog internet-portala Pojmovnik srpske kulture

  17. Franz Kafka’s story The metamorphosis in the light of the theory of intentional object in Franz Brentano and Anton Marty

    Directory of Open Access Journals (Sweden)

    Sonia KAMIŃSKA

    2015-06-01

    Full Text Available How does it feel to be a worm? No doubt, it feels Kafkaesque. The metamorphosis (1915 is a story of an ordinary man, Gregor Samsa, who wakes up one morning as an ungeheures Ungeziefer or ‘giant vermin’. Is this only a bodily change, or has his mind been transformed as well? And how do the people around him cope with this transformation? In this paper, I am going to examine these issues by using tools from Franz Brentano’s (1838–1917 and Anton Marty’s (1847–1914 philosophy of mind and language. Rumour has it that Kafka’s stories were not only products of his own troubled soul, but were also profoundly influenced by the work of these two philosophers. In my paper, I will cover the following issues: the influence of Franz Brentano on Anton Marty and a fortiori on Franz Kafka (1883–1924, who was Marty’s student in Prague (and in this way, saying something about the School of Brentano; Brentano’s and Marty’s theory of correct and incorrect emotions, and its traces in Kafka’s The metamorphosis; Marty’s philosophy of language and communication as reflected in Kafka’s writings; and Brentano’s reism in comparison to Kafka’s nominalism, on the basis of Roberto Calasso’s interpretation of Kafka.

  18. Anticipation of Artemia sp. supply in the larviculture of the barber goby Elacatinus figaro (Gobiidae: Teleostei influenced growth, metamorphosis and alkaline protease activity

    Directory of Open Access Journals (Sweden)

    Maria Fernanda da Silva-Souza

    2015-09-01

    Full Text Available The barber goby Elacatinus figaro is considered endangered due to overexploitation by the ornamental industry. Farming marine ornamental fishes, especially the threatened ones, can be one of the measures to minimize the pressure on the natural stocks. Among the priority issues for their production is the determination of the most appropriate feeding management. The feeding protocol commonly used in the larviculture of barber goby, when the start of Artemia sp. offer occurred at the 18th DAH (days after hatching (treatment T18, was modified, by anticipating brine shrimp supply in 6 days (treatment T12. Alkaline proteases activity, growth and metamorphosis of larvae were evaluated in both protocols. Juveniles at T12 showed higher weight (0.04 ± 0.001 g and lower activity of total alkaline proteases (1.3 ± 0.2 mU mg-1 protein compared to T18 (0.02 ± 0.001 g; 2.8 ± 0.4 mU mg-1 protein, respectively. With anticipation of brine shrimp, the commencing and end of larval transformation was observed earlier (at 24 and 34 DAH, respectively in comparison to those with the supply of Artemia sp. at 18 DAH (27 and 41 DAH, respectively. Thus, the Artemia sp. anticipation was beneficial during the larviculture of the barber goby, considering that larvae reached metamorphosis earlier.

  19. The Metaphoros metamorphosis

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    In the last issue of the Bulletin, the Director-General announced the name of the winner of the architectural competition for the design of the sections of the CERN site adjacent to the route de Meyrin. In this issue, we invite you to take a detailed look at the winning project.   The route de Meyrin, between the Globe (on the right) and the Reception (behind the giant screen), as designed by Studio Bürgi. (Photo: Studio Bürgi sis - Camorino). "Metaphoros" is the name of the winning project submitted by the Ticino architects' office Studio Bürgi in the competition for the design of the sections of the CERN site adjacent to the route de Meyrin. “Metaphoros is derived from the Greek,” explains Paolo Bürgi, the landscape architect who heads the project. “It conveys the idea of transport, travel and communication, which are some of CERN’s defining characteristics!” The aim of the Meta...

  20. The Paranal Metamorphosis

    Science.gov (United States)

    2000-12-01

    Some years ago, the Paranal mountain was still a remote and inhospitable site, some 12 km from the Pacific Coast in the dry Atacama desert in northern Chile. Few aircraft passengers flying along that coast would notice anything particular about this peak, except perhaps that it was one of the tallest in the steep coastal mountain range. Already in the early 1960's, pioneer astronomers crossed this desolate region in search of suitable sites for future observatories. One of them, Jürgen Stock , did notice the Paranal peak as a possible candidate. However, without any water in this extremely dry area, how could any people, even hardy scientists, ever live up there? He then went on to discover La Silla, where ESO decided to build its first observatory in 1964. ESO presence at Paranal from 1983 In the beginning of the 1980's, when the main construction phase at La Silla was over, ESO launched a thorough search for the best possible site for the next-generation telescope, already then known as the "Very Large Telescope", or VLT. During this campaign, the Paranal mountain was visited by a small search troupe from this organisation, including the ESO Director General (1975 - 1987), Lo Woltjer . The first test measurements indicated a great potential for astronomical observations, both in term of clear nights and low humidity, the latter being particularly important for infrared observations. From 1983, ESO maintained a small site testing station at the top of Paranal. The meteorological conditions were registered around the clock and the atmospheric transparency and stability were recorded each night. At that time, the mountain Vizcachas, a site near ESO's first observatory, La Silla, and some 600 km further south, was also considered a possible site for the VLT. The data from the two sites were therefore carefully compared over a period of several years. Paranal becomes the site for the VLT Following the decision in December 1987 by the ESO Council to embark upon the VLT Project (with Massimo Tarenghi as Project Manager), Paranal was chosen as the site in 1991. In the meantime, the Chilean Government had resolved to donate an area of approx. 700 km 2 around this mountain to ESO, and construction work started the same year. The left photo shows Paranal at this stage. The development of Paranal included much blasting and heavy earthwork; about 350,000 m 3 of rock had to be moved to achieve a flat platform of sufficient size to house the various components of the VLT and, in particular, the spacious VLT Interferometer. The situation, right after this work, is depicted in the middle photo from 1994. An operational observatory The construction at Paranal progressed at high speed. It is hard to believe that just four years later, "First Light" was achieved with the first 8.2-m telescope, ANTU, in May 1998. Then followed KUEYEN (March 1999), MELIPAL (January 2000) and YEPUN (September 2000). The first two telescopes have now been "taken over" by the astronomers and Paranal has become an operational observatory with Roberto Gilmozzi as Director. Large numbers of scientists in the ESO member countries, and even more within international collaborations, are busy producing exciting research results, now increasingly visible in the world's professional journals and some of which are announced in the ESO Press Releases. The other two will soon be equipped with high-quality astronomical instruments; the first will be VIMOS at MELIPAL in the beginning of 2001. Both telescopes will become fully available to the astronomical community in the course of 2001. And now the VLT Interferometer... The next decisive step will happen already in early 2001, when the VLT Interferometer is expected to see "First Fringes", the equivalent of "First Light" for this type of facility. This is when two small "siderostats" on the Paranal platform will track and capture the light from one and the same (bright) star, directing the two beams towards the underground Interferometric Laboratory via a series of intermediate mirrors. Here, the critical technical elements are the "delay lines" in the Interferometric Tunnel, cf. ESO Press Photos 26a-e/00.They have already undergone the first tests with very positive results, so the ESO staff is in a confident mood. Later in 2001, two of the 8.2-m Unit Telescopes will be coupled and interferometric test observations will be made on faint celestial objects. In the next years, the three movable 1.8-m Auxiliary Telescopes will be installed on the Paranal "railroad" and the VLT Interferometer will progressively enter into full operation. From a lonely mountain top to the world's foremost optical/infrared astronomical observatory, Paranal has indeed come a long way! This is the caption to ESO PR Photo 36/00 . It may be reproduced, if credit is given to the European Southern Observatory.

  1. Effects of CFT Legumine (5% Rotenone) on tadpole survival and metamorphosis of Chiricahua leopard frogs Lithobates chiricahuensis, Northern leopard frogs L. pipiens, and American bullfrogs L. catesbeianus

    Science.gov (United States)

    Alvarez, Guillermo; Caldwell, Colleen A.; Kruse, Carter G.

    2017-01-01

    Amphibians may experience collateral effects if exposed to CFT Legumine (5% rotenone), a piscicide that is used to remove invasive fish. A series of 48-h static toxicity tests assessed the acute effects of CFT Legumine on multi-aged tadpoles of the federally listed Chiricahua leopard frog Lithobates chiricahuensis, the widespread northern leopard frog L. pipiens, and the increasingly invasive American bullfrog L. catesbeianus. At the earliest Gosner stages (GS 21–25), Chiricahua leopard frogs were more sensitive to CFT Legumine (median lethal concentration [LC50] = 0.41–0.58 mg/L) than American bullfrogs (LC50 = 0.63–0.69 mg/L) and northern leopard frogs (LC50 = 0.91 and 1.17 mg/L). As tadpoles developed (i.e., increase in GS), their sensitivity to rotenone decreased. In a separate series of 48-h static nonrenewal toxicity tests, tadpoles (GS 21–25 and GS 31–36) of all three species were exposed to piscicidal concentrations of CFT Legumine (0.5, 1.0, and 2.0 mg/L) to assess postexposure effects on metamorphosis. In survivors of all three species at both life stages, the time to tail resorption was nearly doubled in comparison with that of controls. For example, mid-age (GS 31–36) Chiricahua leopard frog tadpoles required 210.7 h to complete tail resorption, whereas controls required 108.5 h. However, because tail resorption is a relatively short period in metamorphosis, the total duration of development (days from posthatch to complete metamorphosis) and the final weight did not differ in either age-group surviving nominal concentrations of 0.5-, 1.0-, and 2.0-mg/L CFT Legumine relative to controls. This research demonstrates that the CFT Legumine concentrations commonly used in field applications to remove unwanted fish could result in considerable mortality of the earliest stages of Lithobates species. In addition to acute lethality, piscicide treatments may result in delayed tail resorption, which places the tadpoles at risk by increasing

  2. Systems Biology

    Indian Academy of Sciences (India)

    IAS Admin

    Systems biology seeks to study biological systems as a whole, contrary to the reductionist approach that has dominated biology. Such a view of biological systems emanating from strong foundations of molecular level understanding of the individual components in terms of their form, function and interactions is promising to ...

  3. Molecular cloning of a preprohormone from sea anemones containing numerous copies of a metamorphosis-inducing neuropeptide: a likely role for dipeptidyl aminopeptidase in neuropeptide precursor processing

    DEFF Research Database (Denmark)

    Leviev, I; Grimmelikhuijzen, C J

    1995-01-01

    cleavage sites, and therefore, are also likely to be produced from the precursor. Thus, there are at least 37 closely related neuropeptides localized on the precursor protein, making this precursor one of the most productive preprohormones known so far. This report also shows that unusual processing sites......Neuropeptides are an important group of hormones mediating or modulating neuronal communication. Neuropeptides are especially abundant in evolutionarily "old" nervous systems, such as those of cnidarians, the lowest animal group having a nervous system. Cnidarians often have a life cycle including...... the precursor protein for this metamorphosis-inducing neuropeptide from sea anemones. The precursor protein is 514-amino acid residues long and contains 10 copies of the immature, authentic neuropeptide (Gln-Gln-Pro-Gly-Leu-Trp-Gly). All neuropeptide copies are preceded by Xaa-Pro or Xaa-Ala sequences...

  4. Chemical induction in mangrove crab megalopae, Ucides cordatus (Ucididae): Do young recruits emit metamorphosis-triggering odours as do conspecific adults?

    Science.gov (United States)

    Simith, Darlan de Jesus de Brito; Abrunhosa, Fernando Araújo; Diele, Karen

    2013-10-01

    In many brachyuran species, including the mangrove crab Ucides cordatus, water-soluble chemicals (odours) emitted by adult residents trigger metamorphosis of megalopae, probably facilitating habitat selection and settlement near conspecific crab population. New field findings revealed that early benthic crab stages co-inhabit burrows of both juveniles and adults of U. cordatus which raised the question whether megalopae are also stimulated by sexually immature juveniles. Therefore, we tested in an experimental laboratory study the hypothesis that small benthic recruits and older juveniles also emit metamorphosis-stimulating odours as do conspecific adult crabs. U. cordatus megalopae were cultivated in eight conspecific odour-treatments containing seawater previously conditioned with crabs of different carapace widths (CW 0.15-5.0 cm) and in a control treatment with filtered seawater not conditioned with crabs. In all odour-treatments, including those with small immature crabs, the percentage of metamorphosed larvae was significantly higher (≥74%) and the average development was shorter (15.8-19.3 days) than in the control group, where only 30% moulted after 25.6 ± 6.6 days of megalopal development. In addition, megalopae developed 2.7 days faster when exposed to odours from young and older juveniles compared to those larvae kept in contact with odours from conspecific adults. Our results clearly demonstrate that the emission of metamorphic odours in U. cordatus is independent of size/age or sexual maturity. The responsiveness of megalopae to chemicals emitted by resident crabs of varying ages should aid the natural recovery of U. cordatus populations in areas significantly affected by size-selective fishery where only large conspecific adults are harvested.

  5. Biological computation

    CERN Document Server

    Lamm, Ehud

    2011-01-01

    Introduction and Biological BackgroundBiological ComputationThe Influence of Biology on Mathematics-Historical ExamplesBiological IntroductionModels and Simulations Cellular Automata Biological BackgroundThe Game of Life General Definition of Cellular Automata One-Dimensional AutomataExamples of Cellular AutomataComparison with a Continuous Mathematical Model Computational UniversalitySelf-Replication Pseudo Code Evolutionary ComputationEvolutionary Biology and Evolutionary ComputationGenetic AlgorithmsExample ApplicationsAnalysis of the Behavior of Genetic AlgorithmsLamarckian Evolution Genet

  6. Interaction between Drosophila bZIP proteins Atf3 and Jun prevents replacement of epithelial cells during metamorphosis

    Czech Academy of Sciences Publication Activity Database

    Sekyrová, Petra; Bohmann, D.; Jindra, Marek; Uhlířová, M.

    2010-01-01

    Roč. 137, č. 1 (2010), s. 141-150 ISSN 0950-1991 R&D Projects: GA MŠk 2B06129 Institutional research plan: CEZ:AV0Z50070508 Keywords : epithelial cell replacement * cell adhesion * epidermis Subject RIV: EA - Cell Biology Impact factor: 6.898, year: 2010

  7. 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

  8. Systems Biology

    Energy Technology Data Exchange (ETDEWEB)

    Wiley, H S.

    2006-06-01

    The biology revolution over the last 50 years has been driven by the ascendancy of molecular biology. This was enthusiastically embraced by most biologists because it took us into increasingly familiar territory. It took mysterious processes, such as the replication of genetic material and assigned them parts that could be readily understood by the human mind. When we think of ''molecular machines'' as being the underlying basis of life, we are using a paradigm derived from everyday experience. However, the price that we paid was a relentless drive towards reductionism and the attendant balkanization of biology. Now along comes ''systems biology'' that promises us a solution to the problem of ''knowing more and more about less and less''. Unlike molecular biology, systems biology appears to be taking us into unfamiliar intellectual territory, such as statistics, mathematics and computer modeling. Not surprisingly, systems biology has met with widespread skepticism and resistance. Why do we need systems biology anyway and how does this new area of research promise to change the face of biology in the next couple of decades?

  9. Biological therapeutics

    National Research Council Canada - National Science Library

    Greenstein, Ben; Brook, Daniel A

    2011-01-01

    This introductory textbook covers all the main categories of biological medicines, including vaccines, hormonal preparations, drugs for rheumatoid arthritis and other connective tissue diseases, drugs...

  10. Controls on fluvial metamorphosis during global warming at the Paleocene-Eocene boundary (56 Ma) in Spain: extreme droughts, extreme floods or both?

    Science.gov (United States)

    Castelltort, Sebastien; Chen, Chen; Guerit, Laure; Foreman, Brady; Paola, Chris; Adatte, Thierry

    2017-04-01

    How does global warming change the frequency and intensity of extreme weather events? The response to this question is partly preserved in the geological record. 56 Ma ago, global temperatures increased during the Paleocene-Eocene Thermal Maximum (PETM), leading to a major biotic turnover, but how this event affected the nature of extreme events remains unknown. On several continents, fluvial systems with sinuous channels within fine-grained floodplains suddenly transformed at the P-E boundary into apparently coarser-grained braid plains with frequent lateral migrations, washing their muddy floodplains to the seas. This landscape transformation has been related to aridification and intensification of precipitation allowing transport of coarser material as a result of P-E global warming, with important implications for predicting the consequences of current global change. Here we test this hypothesis by quantifying the magnitude of grain size change and flow depth at a representative P-E locality in Northern Spain. We find that the size of pebbles in transport and flow depth remained similar to, or even smaller than, pre-PETM conditions. This suggests that, if more seasonal and extreme precipitation occurred, they are not necessarily borne out in the predicted deeper flow depths and coarser grain sizes, but rather trigger a shift to multiple active channels. However, an alternative or complementary explanation may rest in pollen data found in coeval marine records and which document a dramatic vegetation shift from permanent conifer forests prior to the crisis into periodic vegetation in brief periods of rain during the hyperthermal episode. Such change induced by long periods of intense droughts, could have enhanced erodibility of channel banks by decreasing root-controlled cohesion of fine-grained floodplains and interfluves, promoting their lateral mobility and the observed fluvial metamorphosis. Thus, although water is regarded as the main agent sculpting

  11. Is synthetic biology mechanical biology?

    Science.gov (United States)

    Holm, Sune

    2015-12-01

    A widespread and influential characterization of synthetic biology emphasizes that synthetic biology is the application of engineering principles to living systems. Furthermore, there is a strong tendency to express the engineering approach to organisms in terms of what seems to be an ontological claim: organisms are machines. In the paper I investigate the ontological and heuristic significance of the machine analogy in synthetic biology. I argue that the use of the machine analogy and the aim of producing rationally designed organisms does not necessarily imply a commitment to mechanical biology. The ideal of applying engineering principles to biology is best understood as expressing recognition of the machine-unlikeness of natural organisms and the limits of human cognition. The paper suggests an interpretation of the identification of organisms with machines in synthetic biology according to which it expresses a strategy for representing, understanding, and constructing living systems that are more machine-like than natural organisms.

  12. Mesoscopic biology

    Indian Academy of Sciences (India)

    Abstract. In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. ... National Center for Biological Sciences, Tata Institute of Fundamental Research, UAS-GKVK Campus, Bangalore 560 065, India ...

  13. Computational biology

    DEFF Research Database (Denmark)

    Hartmann, Lars Røeboe; Jones, Neil; Simonsen, Jakob Grue

    2011-01-01

    Computation via biological devices has been the subject of close scrutiny since von Neumann’s early work some 60 years ago. In spite of the many relevant works in this field, the notion of programming biological devices seems to be, at best, ill-defined. While many devices are claimed or proved t...

  14. Mesoscopic biology

    Indian Academy of Sciences (India)

    In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in biological ...

  15. Effects of metamorphosis and captivity on the in vitro sensitivity of thyroid glands from the tiger salamander, Ambystoma tigrinum, to bovine thyrotropin

    International Nuclear Information System (INIS)

    Norman, M.F.; Norris, D.O.

    1987-01-01

    The sensitivity of thyroid glands from the tiger salamander, Ambystoma tigrinum, to bovine thyrotropin (bTSH) was tested in vitro. Thyroids were taken from subjects representing metamorphic stages I (premetamorphic larvae), II (onset of climax), and VII (completion of gill resorption), as well as from captivity control larvae. Exogenous TSH reduced the cumulative uptake of 125 I in vitro by thyroids from stage I larvae after 24 and 48 hr. The capacity of thyroids to release thyroxine (T4) in vitro was used subsequently as a measure of their responsiveness to TSH. Baseline levels of T4 release in vitro were variable but did not differ significantly among developmental stages. A low dose of bTSH (5 X 10(-6) IU/ml) did not increase in vitro T4 release compared with that of controls. A larger dose (5 X 10(-4) IU/ml) caused greater increases in T4 release from thyroids of stage II and VII subjects than from those of controls. This dose produced only a small response by thyroids from captivity-control subjects. The results suggest that the thyroids of Ambystoma increase in their capacity to respond to TSH during the process of metamorphosis

  16. Essential role of grim-led programmed cell death for the establishment of corazonin-producing peptidergic nervous system during embryogenesis and metamorphosis in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Gyunghee Lee

    2013-01-01

    In Drosophila melanogaster, combinatorial activities of four death genes, head involution defective (hid, reaper (rpr, grim, and sickle (skl, have been known to play crucial roles in the developmentally regulated programmed cell death (PCD of various tissues. However, different expression patterns of the death genes also suggest distinct functions played by each. During early metamorphosis, a great number of larval neurons unfit for adult life style are removed by PCD. Among them are eight pairs of corazonin-expressing larval peptidergic neurons in the ventral nerve cord (vCrz. To reveal death genes responsible for the PCD of vCrz neurons, we examined extant and recently available mutations as well as RNA interference that disrupt functions of single or multiple death genes. We found grim as a chief proapoptotic gene and skl and rpr as minor ones. The function of grim is also required for PCD of the mitotic sibling cells of the vCrz neuronal precursors (EW3-sib during embryonic neurogenesis. An intergenic region between grim and rpr, which, it has been suggested, may enhance expression of three death genes in embryonic neuroblasts, appears to play a role for the vCrz PCD, but not for the EW3-sib cell death. The death of vCrz neurons and EW3-sib is triggered by ecdysone and the Notch signaling pathway, respectively, suggesting distinct regulatory mechanisms of grim expression in a cell- and developmental stage-specific manner.

  17. Mitosis and cell death in the optic lobes of workers, queens and drones of the honey bee (Apis mellifera) during metamorphosis.

    Science.gov (United States)

    Roat, Thaisa Cristina; Landim, Carminda da Cruz

    2010-09-01

    Colonies of the honey bee, Apis mellifera, consist of males and two female castes: workers and queens. The castes and males from A. mellifera have a distinct morphology, physiology and behaviour that correlate with their roles in the society and are characterized by some brain polymorphisms. Compound eyes are one of the characteristics that differ among the castes and sexes. A. mellifera is a holometabolous insect; therefore, the development of adult organs during metamorphosis, which will produce these differences, requires the precise coordination of three main programmed cellular processes: proliferation, differentiation and death. These processes take place simultaneously during pupation. Our purpose was to investigate cell division and death in the optic lobes (OL) of workers, queens and males during pupation to identify how the differences in the compound eyes in adults of these classes are achieved. The results showed that OL differentiation follows a similar pattern in the three classes of individuals studied, without structural differences in their development. The main non-structural differences involve cell division, mortality rates and timing. The results suggest a modelling of the brain during differentiation, which contributes to the specific functions of each individual class.

  18. Fazer a REF é fazer política: memórias de uma metamorfose editorial Making REF is making politics: memories of an editorial metamorphosis

    Directory of Open Access Journals (Sweden)

    Luzinete Simões Minella

    2008-04-01

    Full Text Available Este artigo pretende refletir sobre o novo modelo editorial inaugurado na Revista Estudos Feministas em 2002, ou seja, três anos após a sua instalação na Universidade Federal de Santa Catarina (UFSC. Ao elaborar as memórias dessa metamorfose, nos primeiros itens, refiro-me às transições do formato da editoria da REF, às razões e aos critérios da sua nova estruturação, bem como aos significados da expansão da equipe diante da situação de algumas publicações feministas nacionais e internacionais. No último item elaboro um breve balanço das vantagens e dos desafios implicados nessa nova política editorial.This article focuses on the new editorial model launched in Revista Estudos Feministas in 2002, that is, three years after its installation in Universidade Federal de Santa Catarina (UFSC. While firstly detailing the memories of such metamorphosis, the text refers to the transitions of REF's editorship format, to the purposes and criteria of the new structure, as well as the meanings of the team expansion in relation to some national and international feminist publications. Eventually the article briefly discusses the advantages and challenges implicated in this new editorial policy.

  19. Quantum Biology

    Directory of Open Access Journals (Sweden)

    Alessandro Sergi

    2009-06-01

    Full Text Available A critical assessment of the recent developmentsof molecular biology is presented.The thesis that they do not lead to a conceptualunderstanding of life and biological systems is defended.Maturana and Varela's concept of autopoiesis is briefly sketchedand its logical circularity avoided by postulatingthe existence of underlying living processes,entailing amplification from the microscopic to the macroscopic scale,with increasing complexity in the passage from one scale to the other.Following such a line of thought, the currently accepted model of condensed matter, which is based on electrostatics and short-ranged forces,is criticized. It is suggested that the correct interpretationof quantum dispersion forces (van der Waals, hydrogen bonding, and so onas quantum coherence effects hints at the necessity of includinglong-ranged forces (or mechanisms for them incondensed matter theories of biological processes.Some quantum effects in biology are reviewedand quantum mechanics is acknowledged as conceptually important to biology since withoutit most (if not all of the biological structuresand signalling processes would not even exist. Moreover, it is suggested that long-rangequantum coherent dynamics, including electron polarization,may be invoked to explain signal amplificationprocess in biological systems in general.

  20. Biological Oceanography

    Science.gov (United States)

    Dyhrman, Sonya

    2004-10-01

    The ocean is arguably the largest habitat on the planet, and it houses an astounding array of life, from microbes to whales. As a testament to this diversity and its importance, the discipline of biological oceanography spans studies of all levels of biological organization, from that of single genes, to organisms, to their population dynamics. Biological oceanography also includes studies on how organisms interact with, and contribute to, essential global processes. Students of biological oceanography are often as comfortable looking at satellite images as they are electron micrographs. This diversity of perspective begins the textbook Biological Oceanography, with cover graphics including a Coastal Zone Color Scanner image representing chlorophyll concentration, an electron micrograph of a dinoflagellate, and a photograph of a copepod. These images instantly capture the reader's attention and illustrate some of the different scales on which budding oceanographers are required to think. Having taught a core graduate course in biological oceanography for many years, Charlie Miller has used his lecture notes as the genesis for this book. The text covers the subject of biological oceanography in a manner that is targeted to introductory graduate students, but it would also be appropriate for advanced undergraduates.

  1. Biological Pathways

    Science.gov (United States)

    Skip to main content Biological Pathways Fact Sheet Enter Search Term(s): Español Research Funding An Overview Bioinformatics Current Grants Education and Training Funding Extramural Research News Features ...

  2. Biological preconcentrator

    Science.gov (United States)

    Manginell, Ronald P [Albuquerque, NM; Bunker, Bruce C [Albuquerque, NM; Huber, Dale L [Albuquerque, NM

    2008-09-09

    A biological preconcentrator comprises a stimulus-responsive active film on a stimulus-producing microfabricated platform. The active film can comprise a thermally switchable polymer film that can be used to selectively absorb and desorb proteins from a protein mixture. The biological microfabricated platform can comprise a thin membrane suspended on a substrate with an integral resistive heater and/or thermoelectric cooler for thermal switching of the active polymer film disposed on the membrane. The active polymer film can comprise hydrogel-like polymers, such as poly(ethylene oxide) or poly(n-isopropylacrylamide), that are tethered to the membrane. The biological preconcentrator can be fabricated with semiconductor materials and technologies.

  3. Human development I: Twenty Fundamental Problems of Biology, Medicine, and Neuro-Psychology Related to Biological Information

    Directory of Open Access Journals (Sweden)

    Tyge Dahl Hermansen

    2006-01-01

    Full Text Available In a new series of papers, we address a number of unsolved problems in biology today. First of all, the unsolved enigma concerning how the differentiation from a single zygote to an adult individual happens has been object for severe research for decades. By uncovering a new holistic biological paradigm that introduces an energetic-informational interpretation of reality as a new way to experience biology, these papers will try to solve the problems connected with the events of biological ontogenesis involving a fractal hierarchy, from a single cell to the function of the human brain. The problems discussed are interpreted within the frames of a universe of roomy fractal structures containing energetic patterns that are able to deliver biological information. We think biological organization is guided by energetic changes on the level of quantum mechanics, interacting with the intention that again guides the energetic conformation of the fractal structures to gain disorders or healthiness. Furthermore, we introduce two new concepts: “metamorphous top down” evolution and “adult human metamorphosis”. The first is a new evolutionary theory involving metamorphosis as a main concept of evolution. The last is tightly linked to the evolutionary principle and explains how human self-recovery is governed. Other subjects of special interest that we shall look deeper into are the immunological self-nonself discrimination, the structure and function of the human brain, the etiology and salutogenesis of mental and somatic diseases, and the structure of the consciousness of a human being. We shall criticize Szentagothai’s model for the modulated structure of the human cerebral cortex and Jerne’s theory of the immunological regulatory anti-idiotypic network.

  4. Biological rhythms

    Science.gov (United States)

    Halberg, F.

    1975-01-01

    An overview is given of basic features of biological rhythms. The classification of periodic behavior of physical and psychological characteristics as circadian, circannual, diurnal, and ultradian is discussed, and the notion of relativistic time as it applies in biology is examined. Special attention is given to circadian rhythms which are dependent on the adrenocortical cycle. The need for adequate understanding of circadian variations in the basic physiological indicators of an individual (heart rate, body temperature, systolic and diastolic blood pressure, etc.) to ensure the effectiveness of prophylactic and therapeutic measures is stressed.

  5. The regulatory role of the NO/cGMP signal transduction cascade during larval attachment and metamorphosis of the barnacle Balanus (=Amphibalanus) amphitrite

    KAUST Repository

    Zhang, Y.

    2012-08-01

    The barnacle Balanus amphitrite is among the most dominant fouling species on intertidal rocky shores in tropical and subtropical areas and is thus a target organism in antifouling research. After being released from adults, the swimming nauplius undertakes six molting cycles and then transforms into a cyprid. Using paired antennules, a competent cyprid actively explores and selects a suitable substratum for attachment and metamorphosis (collectively known as settlement). This selection process involves the reception of exogenous signals and subsequent endogenous signal transduction. To investigate the involvement of nitric oxide (NO) and cyclic GMP (cGMP) during larval settlement of B. amphitrite, we examined the effects of an NO donor and an NO scavenger, two nitric oxide synthase (NOS) inhibitors and a soluble guanylyl cyclase (sGC) inhibitor on settling cyprids. We found that the NO donor sodium nitroprusside (SNP) inhibited larval settlement in a dose-dependent manner. In contrast, both the NO scavenger carboxy-PTIO and the NOS inhibitors aminoguanidine hemisulfate (AGH) and S-methylisothiourea sulfate (SMIS) significantly accelerated larval settlement. Suppression of the downstream guanylyl cyclase (GC) activity using a GC-selective inhibitor ODQ could also significantly accelerate larval settlement. Interestingly, the settlement inhibition effects of SNP could be attenuated by ODQ at all concentrations tested. In the developmental expression profiling of NOS and sGC, the lowest expression of both genes was detected in the cyprid stage, a crucial stage for the larval decision to attach and metamorphose. In summary, we concluded that NO regulates larval settlement via mediating downstream cGMP signaling.

  6. Effects of the glyphosate-based herbicide Roundup WeatherMax® on metamorphosis of wood frogs (Lithobates sylvaticus) in natural wetlands.

    Science.gov (United States)

    Lanctôt, C; Robertson, C; Navarro-Martín, L; Edge, C; Melvin, S D; Houlahan, J; Trudeau, V L

    2013-09-15

    Amphibian tadpoles develop in aquatic environments where they are susceptible to the effects of pesticides and other environmental contaminants. Glyphosate-based herbicides are currently the most commonly used herbicide in the world and have been shown to affect survival and development of tadpoles under laboratory and mesocosm conditions. In the present study, whole wetland manipulations were used to determine if exposure to an agriculturally relevant application of Roundup WeatherMax(®), a herbicide formulation containing the potassium salt of glyphosate and an undisclosed surfactant, influences the development of wood frog tadpoles (Lithobates sylvaticus) under natural conditions. Wetlands were divided in half with an impermeable curtain so that each wetland contained a treatment and control side. Tadpoles were exposed to two pulses of this herbicide at an environmentally realistic concentration (ERC, 0.21 mg acid equivalent (a.e.)/L) and the predicted maximum environmental concentration (PMEC, 2.89 mg a.e./L), after which abundance, growth, development, and mRNA levels of genes involved in tadpole metamorphosis were measured. Results present little evidence that exposure to this herbicide affects abundance, growth and development of wood frog tadpoles. As part of the Long-term Experimental Wetlands Area (LEWA) project, this research demonstrates that typical agricultural use of Roundup WeatherMax(®) poses minimal risk to larval amphibian development. However, our gene expression data (mRNA levels) suggests that glyphosate-based herbicides have the potential to alter hormonal pathways during tadpole development. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Marine Biology

    Science.gov (United States)

    Dewees, Christopher M.; Hooper, Jon K.

    1976-01-01

    A variety of informational material for a course in marine biology or oceanology at the secondary level is presented. Among the topics discussed are: food webs and pyramids, planktonic blooms, marine life, plankton nets, food chains, phytoplankton, zooplankton, larval plankton and filter feeders. (BT)

  8. Mesoscopic biology

    Indian Academy of Sciences (India)

    Abstract. In this paper we present a qualitative outlook of mesoscopic biology where the typical length scale is of the order of nanometers and the energy scales comparable to thermal energy. Novel biomolecular machines, governed by coded information at the level of DNA and proteins, operate at these length scales in ...

  9. Scaffolded biology.

    Science.gov (United States)

    Minelli, Alessandro

    2016-09-01

    Descriptions and interpretations of the natural world are dominated by dichotomies such as organism vs. environment, nature vs. nurture, genetic vs. epigenetic, but in the last couple of decades strong dissatisfaction with those partitions has been repeatedly voiced and a number of alternative perspectives have been suggested, from perspectives such as Dawkins' extended phenotype, Turner's extended organism, Oyama's Developmental Systems Theory and Odling-Smee's niche construction theory. Last in time is the description of biological phenomena in terms of hybrids between an organism (scaffolded system) and a living or non-living scaffold, forming unit systems to study processes such as reproduction and development. As scaffold, eventually, we can define any resource used by the biological system, especially in development and reproduction, without incorporating it as happens in the case of resources fueling metabolism. Addressing biological systems as functionally scaffolded systems may help pointing to functional relationships that can impart temporal marking to the developmental process and thus explain its irreversibility; revisiting the boundary between development and metabolism and also regeneration phenomena, by suggesting a conceptual framework within which to investigate phenomena of regular hypermorphic regeneration such as characteristic of deer antlers; fixing a periodization of development in terms of the times at which a scaffolding relationship begins or is terminated; and promoting plant galls to legitimate study objects of developmental biology.

  10. Biological digestion

    International Nuclear Information System (INIS)

    Rosevear, A.

    1988-01-01

    This paper discusses the biological degradation of non-radioactive organic material occurring in radioactive wastes. The biochemical steps are often performed using microbes or isolated enzymes in combination with chemical steps and the aim is to oxidise the carbon, hydrogen, nitrogen and sulphur to their respective oxides. (U.K.)

  11. Biology Notes.

    Science.gov (United States)

    School Science Review, 1981

    1981-01-01

    Outlines a variety of laboratory procedures, techniques, and materials including construction of a survey frame for field biology, a simple tidal system, isolation and applications of plant protoplasts, tropisms, teaching lung structure, and a key to statistical methods for biologists. (DS)

  12. Ancestor of the new archetypal biology: Goethe's dynamic typology as a model for contemporary evolutionary developmental biology.

    Science.gov (United States)

    Riegner, Mark F

    2013-12-01

    As understood historically, typological thinking has no place in evolutionary biology since its conceptual framework is viewed as incompatible with population thinking. In this article, I propose that what I describe as dynamic typological thinking has been confused with, and has been overshadowed by, a static form of typological thinking. This conflation results from an inability to grasp dynamic typological thinking due to the overlooked requirement to engage our cognitive activity in an unfamiliar way. Thus, analytical thinking alone is unsuited to comprehend the nature of dynamic typological thinking. Over 200 years ago, J. W. von Goethe, in his Metamorphosis of Plants (1790) and other writings, introduced a dynamic form of typological thinking that has been traditionally misunderstood and misrepresented. I describe in detail Goethe's phenomenological methodology and its contemporary value in understanding morphological patterns in living organisms. Furthermore, contrary to the implications of static typological thinking, dynamic typological thinking is perfectly compatible with evolutionary dynamics and, if rightly understood, can contribute significantly to the still emerging field of evolutionary developmental biology (evo-devo). Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Biologic Scaffolds.

    Science.gov (United States)

    Costa, Alessandra; Naranjo, Juan Diego; Londono, Ricardo; Badylak, Stephen F

    2017-09-01

    Biologic scaffold materials composed of allogeneic or xenogeneic extracellular matrix are commonly used for the repair and functional reconstruction of injured and missing tissues. These naturally occurring bioscaffolds are manufactured by the removal of the cellular content from source tissues while preserving the structural and functional molecular units of the remaining extracellular matrix (ECM). The mechanisms by which these bioscaffolds facilitate constructive remodeling and favorable clinical outcomes include release or creation of effector molecules that recruit endogenous stem/progenitor cells to the site of scaffold placement and modulation of the innate immune response, specifically the activation of an anti-inflammatory macrophage phenotype. The methods by which ECM biologic scaffolds are prepared, the current understanding of in vivo scaffold remodeling, and the associated clinical outcomes are discussed in this article. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  14. Biological radioprotector

    International Nuclear Information System (INIS)

    Stefanescu, Ioan; Titescu, Gheorghe; Tamaian, Radu; Haulica, Ion; Bild, Walther

    2002-01-01

    According to the patent description, the biological radioprotector is deuterium depleted water, DDW, produced by vacuum distillation with an isotopic content lower than natural value. It appears as such or in a mixture with natural water and carbon dioxide. It can be used for preventing and reducing the ionizing radiation effects upon humans or animal organisms, exposed therapeutically, professionally or accidentally to radiation. The most significant advantage of using DDW as biological radioprotector results from its way of administration. Indeed no one of the radioprotectors currently used today can be orally administrated, what reduces the patients' compliance to prophylactic administrations. The biological radioprotector is an unnoxious product obtained from natural water, which can be administrated as food additive instead of drinking water. Dose modification factor is according to initial estimates around 1.9, what is a remarkable feature when one takes into account that the product is toxicity-free and side effect-free and can be administrated prophylactically as a food additive. A net radioprotective action of the deuterium depletion was evidenced experimentally in laboratory animals (rats) hydrated with DDW of 30 ppm D/(D+H) concentration as compared with normally hydrated control animals. Knowing the effects of irradiation and mechanisms of the acute radiation disease as well as the effects of administration of radiomimetic chemicals upon cellular lines of fast cell division, it appears that the effects of administrating DDW result from stimulation of the immunity system. In conclusion, the biological radioprotector DDW presents the following advantages: - it is obtained from natural products without toxicity; - it is easy to be administrated as a food additive, replacing the drinking water; - besides radioprotective effects, the product has also immunostimulative and antitumoral effects

  15. Crusts: biological

    Science.gov (United States)

    Belnap, Jayne; Elias, Scott A.

    2013-01-01

    Biological soil crusts, a community of cyanobacteria, lichens, mosses, and fungi, are an essential part of dryland ecosystems. They are critical in the stabilization of soils, protecting them from wind and water erosion. Similarly, these soil surface communities also stabilized soils on early Earth, allowing vascular plants to establish. They contribute nitrogen and carbon to otherwise relatively infertile dryland soils, and have a strong influence on hydrologic cycles. Their presence can also influence vascular plant establishment and nutrition.

  16. Marine biology

    International Nuclear Information System (INIS)

    Thurman, H.V.; Webber, H.H.

    1984-01-01

    This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the nature of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index

  17. An evaluation of 2,4-dichlorophenoxyacetic acid in the Amphibian Metamorphosis Assay and the Fish Short-Term Reproduction Assay.

    Science.gov (United States)

    Coady, Katherine; Marino, Troy; Thomas, Johnson; Sosinski, Lindsay; Neal, Barbara; Hammond, Larry

    2013-04-01

    2,4-Dichlorophenoxyacetic acid (2,4-D) was evaluated in both the Amphibian Metamorphosis Assay (AMA) and the Fish Short Term Reproduction Assay (FSTRA). In the AMA, tadpoles were exposed to mean measured 2,4-D concentrations of 0 (water control), 0.273, 3.24, 38.0 and 113 mg acid equivalents (ae)/L for either seven or 21 days. In the FSTRA, fathead minnows were exposed to mean measured 2,4-D concentrations of 0 (water control), 0.245, 3.14, 34.0, and 96.5 mg ae/L for 21 days. The respective concentrations of 2,4-D were not overtly toxic to either Xenopus laevis tadpoles or fathead minnows (Pimephales promelas). In the AMA, there were no signs of either advanced or delayed development, asynchronous development, or significant histopathological effects of the thyroid gland among 2,4-D exposed tadpoles evaluated on either day seven or day 21 of the exposure. Therefore, following the AMA decision logic, 2,4-D is considered "likely thyroid inactive" in the AMA with a No Observable Effect Concentration (NOEC) of 113 mg ae 2,4-D/L. In the FSTRA, there were no significant differences between control and 2,4-D exposed fish in regard to fertility, wet weight, length, gonado-somatic indices, tubercle scores, or blood plasma concentrations of vitellogenin. Furthermore, there were no treatment-related histopathologic changes in the testes or ovaries in any 2,4-D exposed group. The only significant effect was a decrease in fecundity among fish exposed to 96.5 mg ae 2,4-D/L. The cause of the reduced fecundity at the highest concentration of 2,4-D tested in the assay was most likely due to a generalized stress response in the fish, and not due to a specific endocrine mode of action of 2,4-D. Based on fish reproduction, the NOEC in the FSTRA was 34.0 mg ae 2,4-D/L. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. The B vitamins nicotinamide (B3) and riboflavin (B2) stimulate metamorphosis in larvae of the deposit-feeding polychaete Capitella teleta: implications for a sensory ligand-gated ion channel.

    Science.gov (United States)

    Burns, Robert T; Pechenik, Jan A; Biggers, William J; Scavo, Gia; Lehman, Christopher

    2014-01-01

    Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1-2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae.

  19. Biological biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Jorge-Herrero, E. [Servicio de Cirugia Experimental. Clinica Puerta de Hierro, Madrid (Spain)

    1997-05-01

    There are a number of situations in which substances of biological origin are employed as biomaterials. Most of them are macromolecules derived from isolated connective tissue or the connective tissue itself in membrane form, in both cases, the tissue can be used in its natural form or be chemically treated. In other cases, certain blood vessels can be chemically pretreated and used as vascular prostheses. Proteins such as albumin, collagen and fibrinogen are employed to coat vascular prostheses. Certain polysaccharides have also been tested for use in controlled drug release systems. Likewise, a number of tissues, such as dura mater, bovine pericardium, procine valves and human valves, are used in the preparation of cardiac prostheses. We also use veins from animals or humans in arterial replacement. In none of these cases are the tissues employed dissimilar to the native tissues as they have been chemically modified, becoming a new bio material with different physical and biochemical properties. In short, we find that natural products are being utilized as biomaterials and must be considered as such; thus, it is necessary to study both their chemicobiological and physicomechanical properties. In the present report, we review the current applications, problems and future prospects of some of these biological biomaterials. (Author) 84 refs.

  20. Biological effects

    International Nuclear Information System (INIS)

    Trott, K.R.

    1973-01-01

    Following an introduction into the field of cellular radiation effect considering the most important experimental results, the biological significance of the colony formation ability is brought out. The inactivation concept of stem cells does not only prove to be good, according to the present results, in the interpretation of the pathogenesis of acute radiation effects on moult tissue, it also enables chronicle radiation injuries to be interpreted through changes in the fibrous part of the organs. Radiation therapy of tumours can also be explained to a large extent by the radiation effect on the unlimited reproductiveness of tumour cells. The more or less similar dose effect curves for healthy and tumour tissue in practice lead to intermittent irradiation. The dependence of the intermittent doses and intervals on factors such as Elkind recovery, synchronisation, redistribution, reoxygenation, repopulation and regeneration are reviewed. (ORU/LH) [de

  1. The metamorphosis of amphibian toxicogenomics

    Directory of Open Access Journals (Sweden)

    Caren eHelbing

    2012-03-01

    Full Text Available Amphibians are important vertebrates in toxicology often representing both aquatic and terrestrial forms within the life history of the same species. Of the thousands of species, only two have substantial genomics resources: the recently published genome of the Pipid, Xenopus (Silurana tropicalis, and transcript information (and ongoing genome sequencing project of Xenopus laevis. However, many more species representative of regional ecological niches and life strategies are used in toxicology worldwide. Since Xenopus species diverged from the most populous frog family, the Ranidae, ~200 million years ago, there are notable differences between them and the even more distant Caudates (salamanders and Caecilians. These differences include genome size, gene composition, and extent of polyploidization. Application of toxicogenomics to amphibians requires the mobilization of resources and expertise to develop de novo sequence assemblies and analysis strategies for a broader range of amphibian species. The present mini-review will present the advances in toxicogenomics as pertains to amphibians with particular emphasis upon the development and use of genomic techniques (inclusive of transcriptomics, proteomics, and metabolomics and the challenges inherent therein.

  2. The societal metamorphosis of energy

    Energy Technology Data Exchange (ETDEWEB)

    Forscher, F.

    1986-01-01

    This paper proposes that in its largest dimension, energy management will help to bring about needed morphogenic readjustment. The individual, the private sector, and the government, in all their decisions everywhere, must include the concept of energy. Energy management must, in effect, become a subconscious habit of each of us, like the time of day is a subconscious state of mind.

  3. The Metamorphosis by K. (12)

    CERN Multimedia

    CERN Bulletin

    2012-01-01

    In the last issue of the Bulletin we reported on the first run of the new NA62 experiment. In this issue, we go behind the scenes to take a look at the production of the experiment's new kaon beam.   The start of the K12 beam line as seen during the installation of the shielding. 10-2, 10-3, 10-4, 10-5, 10-6 mbar… send in the protons! Since Thursday 1 November, the P42 beam line of the SPS has once again been sending protons to the beryllium target to produce the K12 kaon beam line eagerly awaited by the NA62 collaboration. This was no trivial matter! The first step was to clear the decks by dismantling the entire H10 beam line and NA60 experiment, as well as most of the NA48 experiment - representing some 1000 tonnes of equipment in total! Next came the complete renovation of the infrastructure, which dated back to 1979. The operation called on the expertise of virtually all branches of the EN and GS departments, as well as the Radiation Protection group: from ...

  4. Museum metamorphosis à la mode

    DEFF Research Database (Denmark)

    Baggesen, Rikke Haller

    2014-01-01

    museum practices correspond to the logic of fashion. Where Foucault once described museums as heterochronias; places representing an ’other-time’, museums now strive to be both of their time and in time with the Zeitgeist. As a consequence, they must keep up with the speedy cycles of technological...... advancements and cultural change, and not only deliver, but also stoke the desire for, novel experiences. The paper explores the current vogue for fashion exhibitions as a case in point, arguing that this trend serves to promote the museum as fashionably current, but can also support novel formats for cultural...

  5. The Metamorphosis of School Design.

    Science.gov (United States)

    Hill, Franklin

    1998-01-01

    Discusses ways that schools can evolve to support new teaching and learning paradigms into the new millennium. Argues that 21st-century schools will be smaller, cheaper, and more efficient; simply constructed; revenue generators that are privately financed; integrated with social, governmental, and business entities; will provide multiple,…

  6. Creating biological nanomaterials using synthetic biology.

    Science.gov (United States)

    Rice, MaryJoe K; Ruder, Warren C

    2014-02-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  7. Creating biological nanomaterials using synthetic biology

    International Nuclear Information System (INIS)

    Rice, MaryJoe K; Ruder, Warren C

    2014-01-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems. (review)

  8. Biological effects of radiation

    International Nuclear Information System (INIS)

    2013-01-01

    This fourth chapter presents: cell structure and metabolism; radiation interaction with biological tissues; steps of the production of biological effect of radiation; radiosensitivity of tissues; classification of biological effects; reversibility, transmissivity and influence factors; pre-natal biological effects; biological effects in therapy and syndrome of acute irradiation

  9. Teleology and its constitutive role for biology as the science of organized systems in nature.

    Science.gov (United States)

    Toepfer, Georg

    2012-03-01

    'Nothing in biology makes sense, except in the light of teleology'. This could be the first sentence in a textbook about the methodology of biology. The fundamental concepts in biology, e.g. 'organism' and 'ecosystem', are only intelligible given a teleological framework. Since early modern times, teleology has often been considered methodologically unscientific. With the acceptance of evolutionary theory, one popular strategy for accommodating teleological reasoning was to explain it by reference to selection in the past: functions were reconstructed as 'selected effects'. But the theory of evolution obviously presupposes the existence of organisms as organized and regulated, i.e. functional systems. Therefore, evolutionary theory cannot provide the foundation for teleology. The underlying reason for the central methodological role of teleology in biology is not its potential to offer particular forms of (evolutionary) explanations for the presence of parts, but rather an ontological one: organisms and other basic biological entities do not exist as physical bodies do, as amounts of matter with a definite form. Rather, they are dynamic systems in stable equilibrium; despite changes of their matter and form (in metabolism and metamorphosis) they maintain their identity. What remains constant in these kinds of systems is their 'organization', i.e. the causal pattern of interdependence of parts with certain effects of each part being relevant for the working of the system. Teleological analysis consists in the identification of these system-relevant effects and at the same time of the system as a whole. Therefore, the identity of biological systems cannot be specified without teleological reasoning. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Extra-intestinal localization of Goussia sp (Apicomplexa) oocysts in Rana dalmatina (Anura: Ranidae), and the fate of infection after metamorphosis

    Czech Academy of Sciences Publication Activity Database

    Jirků, M.; Modrý, David

    2006-01-01

    Roč. 70, č. 3 (2006), s. 237-241 ISSN 0177-5103 R&D Projects: GA ČR GA206/03/1544; GA ČR GD524/03/H133 Institutional research plan: CEZ:AV0Z60220518 Keywords : Goussia * Rana * Coccidia Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.509, year: 2006

  11. Dyneins: structure, biology and disease

    National Research Council Canada - National Science Library

    King, Stephen M

    2012-01-01

    .... From bench to bedside, Dynein: Structure, Biology and Disease offers research on fundamental cellular processes to researchers and clinicians across developmental biology, cell biology, molecular biology, biophysics, biomedicine...

  12. Learning Biology by Designing

    Science.gov (United States)

    Janssen, Fred; Waarlo, Arend Jan

    2010-01-01

    According to a century-old tradition in biological thinking, organisms can be considered as being optimally designed. In modern biology this idea still has great heuristic value. In evolutionary biology a so-called design heuristic has been formulated which provides guidance to researchers in the generation of knowledge about biological systems.…

  13. Biological conversion system

    Science.gov (United States)

    Scott, C.D.

    A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

  14. [Biogeography: geography or biology?].

    Science.gov (United States)

    Kafanov, A I

    2009-01-01

    General biogeography is an interdisciplinary science, which combines geographic and biological aspects constituting two distinct research fields: biological geography and geographic biology. These fields differ in the nature of their objects of study, employ different methods and represent Earth sciences and biological sciences, respectively. It is suggested therefore that the classification codes for research fields and the state professional education standard should be revised.

  15. Neuroendocrine gene expression reveals a decrease in dopamine D2B receptor with no changes in GnRH system during prepubertal metamorphosis of silvering in wild Japanese eel.

    Science.gov (United States)

    Jeng, Shan-Ru; Yueh, Wen-Shiun; Pen, Yi-Ting; Lee, Yan-Horn; Chen, Guan-Ru; Dufour, Sylvie; Chang, Ching-Fong

    2014-09-15

    Silvering is a prepubertal metamorphosis preparing the eel to the oceanic reproductive migration. A moderate gonad development occurs during this metamorphosis from the sedentary yellow stage to the migratory silver stage. The aim of this study was to elucidate the molecular aspects of various endocrine parameters of BPG axis at different ovarian developmental stages in wild yellow and silver female Japanese eels. The GSI of the sampled female eels ranged between 0.18 and 2.3%, corresponding to yellow, pre-silver and silver stages. Gonad histology showed changes from previtellogenic oocytes in yellow eels to early vitellogenic oocytes in silver eels. Both serum E2 and T concentrations significantly increased with ovarian development indicating a significant activation of steroidogenesis during silvering. In agreement with previous studies, significant increases in pituitary gonadotropin beta subunits FSH-β and LH-β transcripts were also measured by qPCR, supporting that the activation of pituitary gonadotropin expression is likely responsible for the significant ovarian development observed during silvering. We investigated for the first time the possible brain neuroendocrine mechanisms involved in the activation of the pituitary gonadotropic function during silvering. By analyzing the expression of genes representative of the stimulatory GnRH control and the inhibitory dopaminergic control. The transcript levels of mGnRH and the three GnRH receptors did not change in the brain and pituitary between yellow and silver stages, suggesting that gene expression of the GnRH system is not significantly activated during silvering. The brain transcript levels of tyrosine hydroxylase, limiting enzyme of DA synthesis did not change during silvering, indicating that the DA synthesis activity was maintained. In contrast, a significant decrease in DA-D2B receptor expression in the forebrain and pituitary was observed, with no changes in DA-D2A receptor. The decrease in the

  16. For a dialectic of metamorphosis: the new public and the kaleidoscopic museum Por uma dialética da metamorfose: o novo público e o museu caleidoscópico

    Directory of Open Access Journals (Sweden)

    Christine Ferreira Azzi

    2008-11-01

    Full Text Available The article discusses the dialogue established between the young public and museums, analyzing the contemporaneity of traditional museum discourse. In the light of concepts such as sharing of the sensitive, dialectal images, metamorphosis of artwork and cyberspace, developed by the theoreticians Jacques Rancière, Georges Didi-Huberman, André Malraux and Pierre Lévy, my intention is to question the potential interaction and production of senses exploited, or not, in museum spaces. O artigo põe em cena o diálogo estabelecido pela relação entre público jovem e museus, analisando a contemporaneidade do discurso museológico tradicional. À luz de conceitos como partilha do sensível, imagens dialéticas, metamorfose da obra de arte e ciberespaço, desenvolvidos respectivamente pelos teóricos André Malraux, Georges Didi-Huberman, Jacques Rancière e Pierre Lévy, pretende-se interrogar o potencial de interação e de produção de sentidos utilizado, ou não, pelo espaço museal.

  17. Advances in Biological Science.

    Science.gov (United States)

    Oppenheimer, Steven B.; And Others

    1988-01-01

    Reviews major developments in areas that are at the cutting edge of biological research. Areas include: human anti-cancer gene, recombinant DNA techniques for the detection of Huntington disease carriers, and marine biology. (CW)

  18. Biological basis of detoxication

    National Research Council Canada - National Science Library

    Caldwell, John; Jakoby, William B

    1983-01-01

    This volume considers that premise that most of the major patterns of biological conversion of foreign compounds are known and may have predictive value in assessing the biological course for novel compounds...

  19. Biology of Blood

    Science.gov (United States)

    ... switch to the Professional version Home Blood Disorders Biology of Blood Overview of Blood Resources In This ... Version. DOCTORS: Click here for the Professional Version Biology of Blood Overview of Blood Components of Blood ...

  20. Biological Races in Humans

    OpenAIRE

    Templeton, Alan R.

    2013-01-01

    Races may exist in humans in a cultural sense, but biological concepts of race are needed to access their reality in a non-species-specific manner and to see if cultural categories correspond to biological categories within humans. Modern biological concepts of race can be implemented objectively with molecular genetic data through hypothesis-testing. Genetic data sets are used to see if biological races exist in humans and in our closest evolutionary relative, the chimpanzee. Using the two m...

  1. Biological Age Predictors

    OpenAIRE

    Jylh?v?, Juulia; Pedersen, Nancy L.; H?gg, Sara

    2017-01-01

    The search for reliable indicators of biological age, rather than chronological age, has been ongoing for over three decades, and until recently, largely without success. Advances in the fields of molecular biology have increased the variety of potential candidate biomarkers that may be considered as biological age predictors. In this review, we summarize current state-of-the-art findings considering six potential types of biological age predictors: epigenetic clocks, telomere length, transcr...

  2. Biological Water or Rather Water in Biology?

    Czech Academy of Sciences Publication Activity Database

    Jungwirth, Pavel

    2015-01-01

    Roč. 6, č. 13 (2015), s. 2449-2451 ISSN 1948-7185 Institutional support: RVO:61388963 Keywords : biological water * protein * interface Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 8.539, year: 2015

  3. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Evolutionary Biology Today - The Domain of Evolutionary Biology ... Keywords. Evolution; natural selection; biodiversity; fitness; adaptation. Author Affiliations. Amitabh Joshi1. Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research P.Box 6436, Jakkur Bangalore 560 065, India.

  4. Biology Myth-Killers

    Science.gov (United States)

    Lampert, Evan

    2014-01-01

    "Biology Myth-Killers" is an activity designed to identify and correct common misconceptions for high school and college introductory biology courses. Students identify common myths, which double as biology misconceptions, and use appropriate sources to share the "truth" about the myths. This learner-centered activity is a fun…

  5. Designing synthetic biology.

    Science.gov (United States)

    Agapakis, Christina M

    2014-03-21

    Synthetic biology is frequently defined as the application of engineering design principles to biology. Such principles are intended to streamline the practice of biological engineering, to shorten the time required to design, build, and test synthetic gene networks. This streamlining of iterative design cycles can facilitate the future construction of biological systems for a range of applications in the production of fuels, foods, materials, and medicines. The promise of these potential applications as well as the emphasis on design has prompted critical reflection on synthetic biology from design theorists and practicing designers from many fields, who can bring valuable perspectives to the discipline. While interdisciplinary connections between biologists and engineers have built synthetic biology via the science and the technology of biology, interdisciplinary collaboration with artists, designers, and social theorists can provide insight on the connections between technology and society. Such collaborations can open up new avenues and new principles for research and design, as well as shed new light on the challenging context-dependence-both biological and social-that face living technologies at many scales. This review is inspired by the session titled "Design and Synthetic Biology: Connecting People and Technology" at Synthetic Biology 6.0 and covers a range of literature on design practice in synthetic biology and beyond. Critical engagement with how design is used to shape the discipline opens up new possibilities for how we might design the future of synthetic biology.

  6. Biological Therapies for Cancer

    Science.gov (United States)

    ... Page What is biological therapy? What is the immune system and what role does it have in biological therapy for cancer? ... trials (research studies involving people). What is the immune system and what role does it have in biological therapy for cancer? ...

  7. Synthetic biological networks

    International Nuclear Information System (INIS)

    Archer, Eric; Süel, Gürol M

    2013-01-01

    Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics. (review article)

  8. Biological Control in Agroecosystems

    Science.gov (United States)

    Batra, Suzanne W. T.

    1982-01-01

    Living organisms are used as biological pest control agents in (i) classical biological control, primarily for permanent control of introduced perennial weed pests or introduced pests of perennial crops; (ii) augmentative biological control, for temporary control of native or introduced pests of annual crops grown in monoculture; and (iii) conservative or natural control, in which the agroecosystem is managed to maximize the effect of native or introduced biological control agents. The effectiveness of biological control can be improved if it is based on adequate ecological information and theory, and if it is integrated with other pest management practices.

  9. Quantum biological information theory

    CERN Document Server

    Djordjevic, Ivan B

    2016-01-01

    This book is a self-contained, tutorial-based introduction to quantum information theory and quantum biology. It serves as a single-source reference to the topic for researchers in bioengineering, communications engineering, electrical engineering, applied mathematics, biology, computer science, and physics. The book provides all the essential principles of the quantum biological information theory required to describe the quantum information transfer from DNA to proteins, the sources of genetic noise and genetic errors as well as their effects. Integrates quantum information and quantum biology concepts; Assumes only knowledge of basic concepts of vector algebra at undergraduate level; Provides a thorough introduction to basic concepts of quantum information processing, quantum information theory, and quantum biology; Includes in-depth discussion of the quantum biological channel modelling, quantum biological channel capacity calculation, quantum models of aging, quantum models of evolution, quantum models o...

  10. Standard biological parts knowledgebase.

    Science.gov (United States)

    Galdzicki, Michal; Rodriguez, Cesar; Chandran, Deepak; Sauro, Herbert M; Gennari, John H

    2011-02-24

    We have created the Knowledgebase of Standard Biological Parts (SBPkb) as a publically accessible Semantic Web resource for synthetic biology (sbolstandard.org). The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts (partsregistry.org). SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL), a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  11. Biologic fatigue in psoriasis.

    Science.gov (United States)

    Levin, Ethan C; Gupta, Rishu; Brown, Gabrielle; Malakouti, Mona; Koo, John

    2014-02-01

    Over the past 15 years, biologic medications have greatly advanced psoriasis therapy. However, these medications may lose their efficacy after long-term use, a concept known as biologic fatigue. We sought to review the available data on biologic fatigue in psoriasis and identify strategies to help clinicians optimally manage patients on biologic medications in order to minimize biologic fatigue. We reviewed phase III clinical trials for the biologic medications used to treat psoriasis and performed a PubMed search for the literature that assessed the loss of response to biologic therapy. In phase III clinical trials of biologic therapies for the treatment of psoriasis, 20-32% of patients lost their PASI-75 response during 0.8-3.9 years of follow-up. A study using infliximab reported the highest percentage of patients who lost their response (32%) over the shortest time-period (0.8 years). Although not consistently reported across all studies, the presence of antidrug antibodies was associated with the loss of response to treatment with infliximab and adalimumab. Biologic fatigue may be most frequent in those patients using infliximab. Further studies are needed to identify risk factors associated with biologic fatigue and to develop meaningful antidrug antibody assays.

  12. Standard biological parts knowledgebase.

    Directory of Open Access Journals (Sweden)

    Michal Galdzicki

    2011-02-01

    Full Text Available We have created the Knowledgebase of Standard Biological Parts (SBPkb as a publically accessible Semantic Web resource for synthetic biology (sbolstandard.org. The SBPkb allows researchers to query and retrieve standard biological parts for research and use in synthetic biology. Its initial version includes all of the information about parts stored in the Registry of Standard Biological Parts (partsregistry.org. SBPkb transforms this information so that it is computable, using our semantic framework for synthetic biology parts. This framework, known as SBOL-semantic, was built as part of the Synthetic Biology Open Language (SBOL, a project of the Synthetic Biology Data Exchange Group. SBOL-semantic represents commonly used synthetic biology entities, and its purpose is to improve the distribution and exchange of descriptions of biological parts. In this paper, we describe the data, our methods for transformation to SBPkb, and finally, we demonstrate the value of our knowledgebase with a set of sample queries. We use RDF technology and SPARQL queries to retrieve candidate "promoter" parts that are known to be both negatively and positively regulated. This method provides new web based data access to perform searches for parts that are not currently possible.

  13. Molecular characterization and expression analysis of five different elongation factor 1 alpha genes in the flatfish Senegalese sole (Solea senegalensis Kaup: Differential gene expression and thyroid hormones dependence during metamorphosis

    Directory of Open Access Journals (Sweden)

    Manchado Manuel

    2008-01-01

    Full Text Available Abstract Background Eukaryotic elongation factor 1 alpha (eEF1A is one of the four subunits composing eukaryotic translation elongation factor 1. It catalyzes the binding of aminoacyl-tRNA to the A-site of the ribosome in a GTP-dependent manner during protein synthesis, although it also seems to play a role in other non-translational processes. Currently, little information is still available about its expression profile and regulation during flatfish metamorphosis. With regard to this, Senegalese sole (Solea senegalensis is a commercially important flatfish in which eEF1A gene remains to be characterized. Results The development of large-scale genomics of Senegalese sole has facilitated the identification of five different eEF1A genes, referred to as SseEF1A1, SseEF1A2, SseEF1A3, SseEF1A4, and Sse42Sp50. Main characteristics and sequence identities with other fish and mammalian eEF1As are described. Phylogenetic and tissue expression analyses allowed for the identification of SseEF1A1 and SseEF1A2 as the Senegalese sole counterparts of mammalian eEF1A1 and eEF1A2, respectively, and of Sse42Sp50 as the ortholog of Xenopus laevis and teleost 42Sp50 gene. The other two elongation factors, SseEF1A3 and SseEF1A4, represent novel genes that are mainly expressed in gills and skin. The expression profile of the five genes was also studied during larval development, revealing different behaviours. To study the possible regulation of SseEF1A gene expressions by thyroid hormones (THs, larvae were exposed to the goitrogen thiourea (TU. TU-treated larvae exhibited lower SseEF1A4 mRNA levels than untreated controls at both 11 and 15 days after treatment, whereas transcripts of the other four genes remained relatively unchanged. Moreover, addition of exogenous T4 hormone to TU-treated larvae increased significantly the steady-state levels of SseEF1A4 with respect to untreated controls, demonstrating that its expression is up-regulated by THs. Conclusion We

  14. Effects of larval crowding on development time, survival and weight at metamorphosis in Aedes aegypti (Diptera: Culicidae Efectos del hacinamiento larval en el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis de Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Arnaldo Maciá

    2009-06-01

    Full Text Available The effects of larval crowding on survival, weight at metamorphosis and development time were assessed in the dengue mosquito, Aedes aegypti L., under a controlled environment. Larval cohorts were bred at 7 different densities (4, 8, 16, 32, 64, 128 and 256 larvae / 175 ml pot, while keeping constant water volume and food amount and quality, under controlled temperature and photoperiod. Natural detritus, mainly leaves, obtained from containers naturally colonized by A. aegypti, were used as a source of nutrients for larvae. Development time, mortality, mass at metamorphosis, and total biomass were recorded for each density. Development time ranged from 4 to 23 days in males, and from 5 to 24 in females, whereby larvae took longer to develop at 64 (females and 128 (males larvae per recipient. At high densities there was a male-biased sex proportion. At densities equal to or higher than 0.4 larvae/ml (0.32 larvae/cm² there was an increase of mortality. An inverse relationship between larval density and pupal weight was detected. Biomass per individual reached asymptotic values of about 1 mg/individual at a density of 128 individuals/pot (0.64 larvae/cm². This experiment shows that this southern strain of A. aegypti is sensitive to crowding in small containers.Los efectos del hacinamiento larval sobre el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis fueron estudiados en el mosquito del dengue, Aedes aegypti L., en el laboratorio. Se criaron cohortes de larvas en 7 densidades (4, 8, 16, 32, 64, 128 y 256 larvas/ recipiente de 175 ml mientras se mantuvo constante el volumen de agua y la calidad y cantidad de alimento, bajo fotoperíodo y temperatura controlados. Se usaron detritos naturales, principalmente hojas, obtenidos de contenedores colonizados naturalmente por A. aegypti como fuente de nutrientes para las larvas. En cada densidad se registraron el tiempo de desarrollo, la mortalidad, el peso en la metamorfosis y la

  15. REAL MUSEUM, IMAGINARY MUSEUM: REFLECTIONS ON THE CONCEPT OF THE MUSEUM AS A STAGE FOR METAMORPHOSIS = MUSEO REAL, MUSEO IMAGINARIO: REFLEXIONES EN TORNO AL CONCEPTO DE MUSEO COMO ESCENARIO DE METAMORFOSIS

    Directory of Open Access Journals (Sweden)

    Elena Marcén Guillén

    2014-02-01

    Full Text Available Ever since its inception as public institution in the 18th century, the museum has favoured several interpretations of the work of art, alterations that imply both a change in its semantic and a revision of the very same concept of art. These metamorphoses take place not only within the confined walls of the traditional museum but also in many wall-less museums. Approaches such as the imaginary museum, virtual and endless repertoire of pieces of art, open countless perspectives to how the museums are perceived as containers of the western memory. This paper focuses on the role of the museum as metamorphosis scenery through the thoughts of artists, writers and intellectuals that have felt attracted to this question since the dawn of the museum.Desde sus inicios como institución pública en el siglo XVIII, el museo ha propiciado diversas interpretaciones de la obra de arte, que entrañan tanto un cambio en la semántica del objeto artístico como una revisión del concepto mismo de arte. Estas metamorfosis se producen no solo en el ámbito físico del museo tradicional sino también en las múltiples variedades del museo sin muros. Planteamientos como el del museo imaginario, repertorio virtual e inacabable de obras de arte, abren innumerables perspectivas en lo que se refiere a la institución museística como receptáculo de la memoria occidental. El presente artículo plantea un recorrido por el papel del museo como escenario de metamorfosis a través de las reflexiones de artistas, literatos e intelectuales que se han sentido atraídos por esta sugerente cuestión desde los albores de la institución museística.

  16. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  17. Biological tracer method

    Science.gov (United States)

    Strong-Gunderson, Janet M.; Palumbo, Anthony V.

    1998-01-01

    The present invention is a biological tracer method for characterizing the movement of a material through a medium, comprising the steps of: introducing a biological tracer comprising a microorganism having ice nucleating activity into a medium; collecting at least one sample of the medium from a point removed from the introduction point; and analyzing the sample for the presence of the biological tracer. The present invention is also a method for using a biological tracer as a label for material identification by introducing a biological tracer having ice nucleating activity into a material, collecting a sample of a portion of the labelled material and analyzing the sample for the presence of the biological tracer.

  18. Plant synthetic biology.

    Science.gov (United States)

    Liu, Wusheng; Stewart, C Neal

    2015-05-01

    Plant synthetic biology is an emerging field that combines engineering principles with plant biology toward the design and production of new devices. This emerging field should play an important role in future agriculture for traditional crop improvement, but also in enabling novel bioproduction in plants. In this review we discuss the design cycles of synthetic biology as well as key engineering principles, genetic parts, and computational tools that can be utilized in plant synthetic biology. Some pioneering examples are offered as a demonstration of how synthetic biology can be used to modify plants for specific purposes. These include synthetic sensors, synthetic metabolic pathways, and synthetic genomes. We also speculate about the future of synthetic biology of plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Biological detector and method

    Science.gov (United States)

    Sillerud, Laurel; Alam, Todd M; McDowell, Andrew F

    2013-02-26

    A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.

  20. Biological Water Quality Criteria

    Science.gov (United States)

    Page contains links to Technical Documents pertaining to Biological Water Quality Criteria, including, technical assistance documents for states, tribes and territories, program overviews, and case studies.

  1. Space Synthetic Biology (SSB)

    Data.gov (United States)

    National Aeronautics and Space Administration — This project focused on employing advanced biological engineering and bioelectrochemical reactor systems to increase life support loop closure and in situ resource...

  2. Systems Biology of Metabolism.

    Science.gov (United States)

    Nielsen, Jens

    2017-06-20

    Metabolism is highly complex and involves thousands of different connected reactions; it is therefore necessary to use mathematical models for holistic studies. The use of mathematical models in biology is referred to as systems biology. In this review, the principles of systems biology are described, and two different types of mathematical models used for studying metabolism are discussed: kinetic models and genome-scale metabolic models. The use of different omics technologies, including transcriptomics, proteomics, metabolomics, and fluxomics, for studying metabolism is presented. Finally, the application of systems biology for analyzing global regulatory structures, engineering the metabolism of cell factories, and analyzing human diseases is discussed.

  3. Biological Clocks & Circadian Rhythms

    Science.gov (United States)

    Robertson, Laura; Jones, M. Gail

    2009-01-01

    The study of biological clocks and circadian rhythms is an excellent way to address the inquiry strand in the National Science Education Standards (NSES) (NRC 1996). Students can study these everyday phenomena by designing experiments, gathering and analyzing data, and generating new experiments. As students explore biological clocks and circadian…

  4. Biologic Patterns of Disability.

    Science.gov (United States)

    Granger, Carl V.; Linn, Richard T.

    2000-01-01

    Describes the use of Rasch analysis to elucidate biological patterns of disability present in the functional ability of persons undergoing medical rehabilitation. Uses two measures, one for inpatients and one for outpatients, to illustrate the approach and provides examples of some biological patterns of disability associated with specific types…

  5. Archives: Tropical Freshwater Biology

    African Journals Online (AJOL)

    Items 1 - 23 of 23 ... Archives: Tropical Freshwater Biology. Journal Home > Archives: Tropical Freshwater Biology. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 23 of 23 Items ...

  6. Advances in radiation biology

    International Nuclear Information System (INIS)

    Lett, J.T.; Ehmann, U.K.; Cox, A.B.

    1987-01-01

    The classical period of radiation biology is coming to a close. Such change always occurs at a time when the ideas and concepts that promoted the burgeoning of an infant science are no longer adequate. This volume covers a number of areas in which new ideas and research are playing a vital role, including cellular radiation sensitivity, radioactive waste disposal, and space radiation biology

  7. Psoriasis : implications of biologics

    NARCIS (Netherlands)

    Lecluse, L.L.A.

    2010-01-01

    Since the end of 2004 several specific immunomodulating therapies: ‘biologic response modifiers’ or ‘biologics’ have been registered for moderate to severe psoriasis in Europe. This thesis is considering the implications of the introduction of the biologics for psoriasis patients, focusing on safety

  8. Tropical Freshwater Biology

    African Journals Online (AJOL)

    Tropical Freshwater Biology promotes the publication of scientific contributions in the field of freshwater biology in the tropical and subtropical regions of the world. One issue is published annually but this number may be increased. Original research papers and short communications on any aspect of tropical freshwater ...

  9. Experimenting with Mathematical Biology

    Science.gov (United States)

    Sanft, Rebecca; Walter, Anne

    2016-01-01

    St. Olaf College recently added a Mathematical Biology concentration to its curriculum. The core course, Mathematics of Biology, was redesigned to include a wet laboratory. The lab classes required students to collect data and implement the essential modeling techniques of formulation, implementation, validation, and analysis. The four labs…

  10. Physics and biology

    International Nuclear Information System (INIS)

    Frauenfelder, H.

    1988-01-01

    The author points out that the coupling between physics and biology is becoming closer as time goes on. He tries to show that physical studies on biological systems not only yield insight into biology but also provide results of interest to physics. Biological systems are extremly complex system. Ideally one would like to understand the behavior of such systems in terms of the behavior of its constituent atoms. Since in small organisms this may be 10 20 atoms, it is clear these are not simple many-body systems. He reviews the basic elements of cells and then considers the broader questions of structure, complexity, and function, which must be looked at on levels from the cell to the organism. Despite the vast amount of observational material already in existence, biophysics and biological physics are only at a beginning. We can expect that physics will continue to interact strongly with biology. Actually, the connection also includes chemistry and mathematics. New tools that become available in physics will continue to be applied to biological problems. We can expect that the flow of information will not be one way; biological systems will provide new information on many old and new parts of physics, from reaction theory and transport phenomena to complexity, cooperativity, and nonlinear processes

  11. Integrated Biological Control

    International Nuclear Information System (INIS)

    JOHNSON, A.R.

    2002-01-01

    Biological control is any activity taken to prevent, limit, clean up, or remediate potential environmental, health and safety, or workplace quality impacts from plants, animals, or microorganisms. At Hanford the principal emphasis of biological control is to prevent the transport of radioactive contamination by biological vectors (plants, animals, or microorganisms), and where necessary, control and clean up resulting contamination. Other aspects of biological control at Hanford include industrial weed control (e.g.; tumbleweeds), noxious weed control (invasive, non-native plant species), and pest control (undesirable animals such as rodents and stinging insects; and microorganisms such as molds that adversely affect the quality of the workplace environment). Biological control activities may be either preventive (apriori) or in response to existing contamination spread (aposteriori). Surveillance activities, including ground, vegetation, flying insect, and other surveys, and apriori control actions, such as herbicide spraying and placing biological barriers, are important in preventing radioactive contamination spread. If surveillance discovers that biological vectors have spread radioactive contamination, aposteriori control measures, such as fixing contamination, followed by cleanup and removal of the contamination to an approved disposal location are typical response functions. In some cases remediation following the contamination cleanup and removal is necessary. Biological control activities for industrial weeds, noxious weeds and pests have similar modes of prevention and response

  12. Biological sample collector

    Science.gov (United States)

    Murphy, Gloria A [French Camp, CA

    2010-09-07

    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  13. Frontiers in mathematical biology

    CERN Document Server

    1994-01-01

    Volume 100, which is the final volume of the LNBM series serves to commemorate the acievements in two decades of this influential collection of books in mathematical biology. The contributions, by the leading mathematical biologists, survey the state of the art in the subject, and offer speculative, philosophical and critical analyses of the key issues confronting the field. The papers address fundamental issues in cell and molecular biology, organismal biology, evolutionary biology, population ecology, community and ecosystem ecology, and applied biology, plus the explicit and implicit mathematical challenges. Cross-cuttting issues involve the problem of variation among units in nonlinear systems, and the related problems of the interactions among phenomena across scales of space, time and organizational complexity.

  14. Biological Age Predictors

    Directory of Open Access Journals (Sweden)

    Juulia Jylhävä

    2017-07-01

    Full Text Available The search for reliable indicators of biological age, rather than chronological age, has been ongoing for over three decades, and until recently, largely without success. Advances in the fields of molecular biology have increased the variety of potential candidate biomarkers that may be considered as biological age predictors. In this review, we summarize current state-of-the-art findings considering six potential types of biological age predictors: epigenetic clocks, telomere length, transcriptomic predictors, proteomic predictors, metabolomics-based predictors, and composite biomarker predictors. Promising developments consider multiple combinations of these various types of predictors, which may shed light on the aging process and provide further understanding of what contributes to healthy aging. Thus far, the most promising, new biological age predictor is the epigenetic clock; however its true value as a biomarker of aging requires longitudinal confirmation.

  15. Mammalian Synthetic Biology: Engineering Biological Systems.

    Science.gov (United States)

    Black, Joshua B; Perez-Pinera, Pablo; Gersbach, Charles A

    2017-06-21

    The programming of new functions into mammalian cells has tremendous application in research and medicine. Continued improvements in the capacity to sequence and synthesize DNA have rapidly increased our understanding of mechanisms of gene function and regulation on a genome-wide scale and have expanded the set of genetic components available for programming cell biology. The invention of new research tools, including targetable DNA-binding systems such as CRISPR/Cas9 and sensor-actuator devices that can recognize and respond to diverse chemical, mechanical, and optical inputs, has enabled precise control of complex cellular behaviors at unprecedented spatial and temporal resolution. These tools have been critical for the expansion of synthetic biology techniques from prokaryotic and lower eukaryotic hosts to mammalian systems. Recent progress in the development of genome and epigenome editing tools and in the engineering of designer cells with programmable genetic circuits is expanding approaches to prevent, diagnose, and treat disease and to establish personalized theranostic strategies for next-generation medicines. This review summarizes the development of these enabling technologies and their application to transforming mammalian synthetic biology into a distinct field in research and medicine.

  16. Managing biological diversity

    Science.gov (United States)

    Samson, Fred B.; Knopf, Fritz L.

    1993-01-01

    Biological diversity is the variety of life and accompanying ecological processes (Off. Technol. Assess. 1987, Wilcove and Samson 1987, Keystone 1991). Conservation of biological diversity is a major environmental issue (Wilson 1988, Counc. Environ. Quality 1991). The health and future of the earth's ecological systems (Lubchenco et al. 1991), global climate change (Botkin 1990), and an ever-increasing rate in loss of species, communities, and ecological systems (Myers 1990) are among issues drawing biological diversity to the mainstream of conservation worldwide (Int. Union Conserv. Nat. and Nat. Resour. [IUCN] et al. 1991). The legal mandate for conserving biological diversity is now in place (Carlson 1988, Doremus 1991). More than 19 federal laws govern the use of biological resources in the United States (Rein 1991). The proposed National Biological Diversity Conservation and Environmental Research Act (H.R. 585 and S.58) notes the need for a national biological diversity policy, would create a national center for biological diversity research, and recommends a federal interagency strategy for ecosystem conservation. There are, however, hard choices ahead for the conservation of biological diversity, and biologists are grappling with how to set priorities in research and management (Roberts 1988). We sense disillusion among field biologists and managers relative to how to operationally approach the seemingly overwhelming charge of conserving biological diversity. Biologists also need to respond to critics like Hunt (1991) who suggest a tree farm has more biological diversity than an equal area of old-growth forest. At present, science has played only a minor role in the conservation of biological diversity (Weston 1992) with no unified approach available to evaluate strategies and programs that address the quality and quantity of biological diversity (Murphy 1990, Erwin 1992). Although actions to conserve biological diversity need to be clearly defined by

  17. A timeless biology.

    Science.gov (United States)

    Tozzi, Arturo; Peters, James F; Chafin, Clifford; De Falco, Domenico; Torday, John S

    2018-05-01

    Contrary to claims that physics is timeless while biology is time-dependent, we take the opposite standpoint: physical systems' dynamics are constrained by the arrow of time, while living assemblies are time-independent. Indeed, the concepts of "constraints" and "displacements" shed new light on the role of continuous time flow in life evolution, allowing us to sketch a physical gauge theory for biological systems in long timescales. In the very short timescales of biological systems' individual lives, time looks like "frozen" and "fixed", so that the second law of thermodynamics is momentarily wrecked. The global symmetries (standing for biological constrained trajectories, i.e. the energetic gradient flows dictated by the second law of thermodynamics in long timescales) are broken by local "displacements" where time is held constant, i.e., modifications occurring in living systems. Such displacements stand for brief local forces, able to temporarily "break" the cosmic increase in entropy. The force able to restore the symmetries (called "gauge field") stands for the very long timescales of biological evolution. Therefore, at the very low speeds of life evolution, time is no longer one of the four phase space coordinates of a spacetime Universe: it becomes just a gauge field superimposed to three-dimensional biological systems. We discuss the implications in biology: when assessing living beings, the underrated role of isolated "spatial" modifications needs to be emphasized, living apart the evolutionary role of time. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Noise in biological circuits.

    Science.gov (United States)

    Simpson, Michael L; Cox, Chris D; Allen, Michael S; McCollum, James M; Dar, Roy D; Karig, David K; Cooke, John F

    2009-01-01

    Noise biology focuses on the sources, processing, and biological consequences of the inherent stochastic fluctuations in molecular transitions or interactions that control cellular behavior. These fluctuations are especially pronounced in small systems where the magnitudes of the fluctuations approach or exceed the mean value of the molecular population. Noise biology is an essential component of nanomedicine where the communication of information is across a boundary that separates small synthetic and biological systems that are bound by their size to reside in environments of large fluctuations. Here we review the fundamentals of the computational, analytical, and experimental approaches to noise biology. We review results that show that the competition between the benefits of low noise and those of low population has resulted in the evolution of genetic system architectures that produce an uneven distribution of stochasticity across the molecular components of cells and, in some cases, use noise to drive biological function. We review the exact and approximate approaches to gene circuit noise analysis and simulation, and review many of the key experimental results obtained using flow cytometry and time-lapse fluorescent microscopy. In addition, we consider the probative value of noise with a discussion of using measured noise properties to elucidate the structure and function of the underlying gene circuit. We conclude with a discussion of the frontiers of and significant future challenges for noise biology. (c) 2009 John Wiley & Sons, Inc.

  19. Neutron in biology

    International Nuclear Information System (INIS)

    Niimura, Nobuo

    1997-01-01

    Neutron in biology can provide an experimental method of directly locating relationship of proteins and DNA. However, there are relatively few experimental study of such objects since it takes a lot of time to collect a sufficient number of Bragg reflections and inelastic spectra due to the low flux of neutron illuminating the sample. Since a next generation neutron source of JAERI will be 5MW spallation neutron source and its effective neutron flux will be 10 2 to 10 3 times higher than the one of JRR-3M, neutron in biology will open a completely new world for structural biology. (author)

  20. ERLN Biological Focus Area

    Science.gov (United States)

    The Environmental Response Laboratory Network supports the goal to increase national capacity for biological analysis of environmental samples. This includes methods development and verification, technology transfer, and collaboration with USDA, FERN, CDC.

  1. Biological and Pharmacological properties

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Biological and Pharmacological properties. NOEA inhibits Ceramidase. Anandamide inhibits gap junction conductance and reduces sperm fertilizing capacity. Endogenous ligands for Cannabinoid receptors (anandamide and NPEA). Antibacterial and antiviral ...

  2. Synthetic Biological Membrane (SBM)

    Data.gov (United States)

    National Aeronautics and Space Administration — The ultimate goal of the Synthetic Biological Membrane project is to develop a new type of membrane that will enable the wastewater treatment system required on...

  3. EDITORIAL: Physical Biology

    Science.gov (United States)

    Roscoe, Jane

    2004-06-01

    Physical Biology is a new peer-reviewed publication from Institute of Physics Publishing. Launched in 2004, the journal will foster the integration of biology with the traditionally more quantitative fields of physics, chemistry, computer science and other math-based disciplines. Its primary aim is to further the understanding of biological systems at all levels of complexity, ranging from the role of structure and dynamics of a single molecule to cellular networks and organisms. The journal encourages the development of a new biology-driven physics based on the extraordinary and increasingly rich data arising in biology, and provides research directions for those involved in the creation of novel bio-engineered systems. Physical Biology will publish a stimulating combination of full length research articles, communications, perspectives, reviews and tutorials from a wide range of disciplines covering topics such as: Single-molecule studies and nanobiotechnology Molecular interactions and protein folding Charge transfer and photobiology Ion channels; structure, function and ion regulation Molecular motors and force generation Subcellular processes Biological networks and neural systems Modeling aspects of molecular and cell biology Cell-cell signaling and interaction Biological patterns and development Evolutionary processes Novel tools and methods in physical biology Experts in the areas encompassed by the journal's scope have been appointed to the Editorial Scientific Committee and the composition of the Committee will be updated regularly to reflect the developments in this new and exciting field. Physical Biology is free online to everyone in 2004; you are invited to take advantage of this offer by visiting the journal homepage at http://physbio.iop.org This special print edition of Physical Biology is a combination of issues 1 and 2 of this electronic-only journal and it brings together an impressive range of articles in the fields covered, including a popular

  4. The Biology of Behaviour.

    Science.gov (United States)

    Broom, D. M.

    1981-01-01

    Discusses topics to aid in understanding animal behavior, including the value of the biological approach to psychology, functional systems, optimality and fitness, universality of environmental effects on behavior, and evolution of social behavior. (DS)

  5. Large Pelagics Biological Survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Large Pelagics Biological Survey (LPBS) collects additional length and weight information and body parts such as otoliths, caudal vertebrae, dorsal spines, and...

  6. Fishery Biology Database (AGDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basic biological data are the foundation on which all assessments of fisheries resources are built. These include parameters such as the size and age composition of...

  7. Mechanical Biological Treatment

    DEFF Research Database (Denmark)

    Bilitewski, B-; Oros, Christiane; Christensen, Thomas Højlund

    2011-01-01

    The basic processes and technologies of composting and anaerobic digestion, as described in the previous chapters, are usually used for specific or source-separated organic waste flows. However, in the 1990s mechanical biological waste treatment technologies (MBT) were developed for unsorted...... or residual waste (after some recyclables removed at the source). The concept was originally to reduce the amount of waste going to landfill, but MBT technologies are today also seen as plants recovering fuel as well as material fractions. As the name suggests the technology combines mechanical treatment...... technologies (screens, sieves, magnets, etc.) with biological technologies (composting, anaerobic digestion). Two main technologies are available: Mechanical biological pretreatment (MBP), which first removes an RDF fraction and then biologically treats the remaining waste before most of it is landfilled...

  8. Study of biological compartments

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da

    1976-01-01

    The several types of biological compartments are studied such as monocompartmental system, one-compartment balanced system irreversible fluxes, two closed compartment system, three compartment systems, catenary systems and mammilary systems [pt

  9. Enhanced Biological Sampling Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a database of a variety of biological, reproductive, and energetic data collected from fish on the continental shelf in the northwest Atlantic Ocean. Species...

  10. Hammond Bay Biological Station

    Data.gov (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  11. Laboratory of Biological Modeling

    Data.gov (United States)

    Federal Laboratory Consortium — The Laboratory of Biological Modeling is defined by both its methodologies and its areas of application. We use mathematical modeling in many forms and apply it to a...

  12. Insecticides and Biological Control

    Science.gov (United States)

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  13. Standardization in synthetic biology.

    Science.gov (United States)

    Müller, Kristian M; Arndt, Katja M

    2012-01-01

    Synthetic Biology is founded on the idea that complex biological systems are built most effectively when the task is divided in abstracted layers and all required components are readily available and well-described. This requires interdisciplinary collaboration at several levels and a common understanding of the functioning of each component. Standardization of the physical composition and the description of each part is required as well as a controlled vocabulary to aid design and ensure interoperability. Here, we describe standardization initiatives from several disciplines, which can contribute to Synthetic Biology. We provide examples of the concerted standardization efforts of the BioBricks Foundation comprising the request for comments (RFC) and the Registry of Standardized Biological parts as well as the international Genetically Engineered Machine (iGEM) competition.

  14. Nutritional Systems Biology

    DEFF Research Database (Denmark)

    Jensen, Kasper

    and network biology has the potential to increase our understanding of how small molecules affect metabolic pathways and homeostasis, how this perturbation changes at the disease state, and to what extent individual genotypes contribute to this. A fruitful strategy in approaching and exploring the field...... biology research. The paper also shows as a proof-of-concept that a systems biology approach to diet is meaningful and demonstrates some basic principles on how to work with diet systematic. The second chapter of this thesis we developed the resource NutriChem v1.0. A foodchemical database linking...... sites of diet on the disease pathway. We propose a framework for interrogating the critical targets in colon cancer process and identifying plant-based dietary interventions as important modifiers using a systems chemical biology approach. The fifth chapter of the thesis is on discovering of novel anti...

  15. Coordination Compounds in Biology

    Indian Academy of Sciences (India)

    . Some of the other important examples are chlorophyll, haemoglobin, myoglobin and cytochromes. The common feature in .... Biochemical Function (in vivo Studies). B. 12 functions in biological systems as a coenzyme. That is, it binds.

  16. Human papillomavirus molecular biology.

    Science.gov (United States)

    Harden, Mallory E; Munger, Karl

    Human papillomaviruses are small DNA viruses with a tropism for squamous epithelia. A unique aspect of human papillomavirus molecular biology involves dependence on the differentiation status of the host epithelial cell to complete the viral lifecycle. A small group of these viruses are the etiologic agents of several types of human cancers, including oral and anogenital tract carcinomas. This review focuses on the basic molecular biology of human papillomaviruses. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Graphs in molecular biology

    Directory of Open Access Journals (Sweden)

    Falcon Seth

    2007-09-01

    Full Text Available Abstract Graph theoretical concepts are useful for the description and analysis of interactions and relationships in biological systems. We give a brief introduction into some of the concepts and their areas of application in molecular biology. We discuss software that is available through the Bioconductor project and present a simple example application to the integration of a protein-protein interaction and a co-expression network.

  18. Molecular Biology Database List.

    Science.gov (United States)

    Burks, C

    1999-01-01

    Molecular Biology Database List (MBDL) includes brief descriptions and pointers to Web sites for the various databases described in this issue as well as other Web sites presenting data sets relevant to molecular biology. This information is compiled into a list (http://www.oup.co.uk/nar/Volume_27/Issue_01/summary/ gkc105_gml.html) which includes links both to source Web sites and to on-line versions of articles describing the databases. PMID:9847130

  19. Teaching systems biology.

    Science.gov (United States)

    Alves, R; Vilaprinyo, E; Sorribas, A

    2011-03-01

    Advances in systems biology are increasingly dependent upon the integration of various types of data and different methodologies to reconstruct how cells work at the systemic level. Thus, teams with a varied array of expertise and people with interdisciplinary training are needed. So far this training was thought to be more productive if aimed at the Masters or PhD level. At this level, multiple specialised and in-depth courses on the different subject matters of systems biology are taught to already well-prepared students. This approach is mostly based on the recognition that systems biology requires a wide background that is hard to find in undergraduate students. Nevertheless, and given the importance of the field, the authors argue that exposition of undergraduate students to the methods and paradigms of systems biology would be advantageous. Here they present and discuss a successful experiment in teaching systems biology to third year undergraduate biotechnology students at the University of Lleida in Spain. The authors' experience, together with that from others, argues for the adequateness of teaching systems biology at the undergraduate level. [Includes supplementary material].

  20. Developmental biology, the stem cell of biological disciplines.

    Science.gov (United States)

    Gilbert, Scott F

    2017-12-01

    Developmental biology (including embryology) is proposed as "the stem cell of biological disciplines." Genetics, cell biology, oncology, immunology, evolutionary mechanisms, neurobiology, and systems biology each has its ancestry in developmental biology. Moreover, developmental biology continues to roll on, budding off more disciplines, while retaining its own identity. While its descendant disciplines differentiate into sciences with a restricted set of paradigms, examples, and techniques, developmental biology remains vigorous, pluripotent, and relatively undifferentiated. In many disciplines, especially in evolutionary biology and oncology, the developmental perspective is being reasserted as an important research program.

  1. Development trend of radiation biology research-systems radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2010-01-01

    Radiation biology research has past 80 years. We have known much more about fundamentals, processes and results of biology effects induced by radiation and various factors that influence biology effects wide and deep, however many old and new scientific problems occurring in the field of radiation biology research remain to be illustrated. To explore and figure these scientific problems need systemic concept, methods and multi dimension view on the base of considerations of complexity of biology system, diversity of biology response, temporal and spatial process of biological effects during occurrence, and complex feed back network of biological regulations. (authors)

  2. Understanding Biological Regulation Through Synthetic Biology.

    Science.gov (United States)

    Bashor, Caleb J; Collins, James J

    2018-03-16

    Engineering synthetic gene regulatory circuits proceeds through iterative cycles of design, building, and testing. Initial circuit designs must rely on often-incomplete models of regulation established by fields of reductive inquiry-biochemistry and molecular and systems biology. As differences in designed and experimentally observed circuit behavior are inevitably encountered, investigated, and resolved, each turn of the engineering cycle can force a resynthesis in understanding of natural network function. Here, we outline research that uses the process of gene circuit engineering to advance biological discovery. Synthetic gene circuit engineering research has not only refined our understanding of cellular regulation but furnished biologists with a toolkit that can be directed at natural systems to exact precision manipulation of network structure. As we discuss, using circuit engineering to predictively reorganize, rewire, and reconstruct cellular regulation serves as the ultimate means of testing and understanding how cellular phenotype emerges from systems-level network function. Expected final online publication date for the Annual Review of Biophysics Volume 47 is May 20, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  3. Biological process linkage networks.

    Directory of Open Access Journals (Sweden)

    Dikla Dotan-Cohen

    Full Text Available The traditional approach to studying complex biological networks is based on the identification of interactions between internal components of signaling or metabolic pathways. By comparison, little is known about interactions between higher order biological systems, such as biological pathways and processes. We propose a methodology for gleaning patterns of interactions between biological processes by analyzing protein-protein interactions, transcriptional co-expression and genetic interactions. At the heart of the methodology are the concept of Linked Processes and the resultant network of biological processes, the Process Linkage Network (PLN.We construct, catalogue, and analyze different types of PLNs derived from different data sources and different species. When applied to the Gene Ontology, many of the resulting links connect processes that are distant from each other in the hierarchy, even though the connection makes eminent sense biologically. Some others, however, carry an element of surprise and may reflect mechanisms that are unique to the organism under investigation. In this aspect our method complements the link structure between processes inherent in the Gene Ontology, which by its very nature is species-independent. As a practical application of the linkage of processes we demonstrate that it can be effectively used in protein function prediction, having the power to increase both the coverage and the accuracy of predictions, when carefully integrated into prediction methods.Our approach constitutes a promising new direction towards understanding the higher levels of organization of the cell as a system which should help current efforts to re-engineer ontologies and improve our ability to predict which proteins are involved in specific biological processes.

  4. Biological Effects of Ionizing Radiation

    Science.gov (United States)

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  5. Biological Effects of Radiation

    International Nuclear Information System (INIS)

    Jatau, B.D.; Garba, N.N.; Yusuf, A.M.; Yamusa, Y. A.; Musa, Y.

    2013-01-01

    In earlier studies, researchers aimed a single particle at the nucleus of the cell where DNA is located. Eighty percent of the cells shot through the nucleus survived. This contradicts the belief that if radiation slams through the nucleus, the cell will die. But the bad news is that the surviving cells contained mutations. Cells have a great capacity to repair DNA, but they cannot do it perfectly. The damage left behind in these studies from a single particle of alpha radiation doubled the damage that is already there. This proved, beyond a shadow of doubt, those there biological effects occur as a result of exposure to radiation, Radiation is harmful to living tissue because of its ionizing power in matter. This ionization can damage living cells directly, by breaking the chemical bonds of important biological molecules (particularly DNA), or indirectly, by creating chemical radicals from water molecules in the cells, which can then attack the biological molecules chemically. At some extent these molecules are repaired by natural biological processes, however, the effectiveness of this repair depends on the extent of the damage. The interaction of ionizing with the human body, arising either from external sources outside the body or from internal contamination of the body by radioactive materials, leads to the biological effects which may later show up as a clinical symptoms. Basically, this formed the baseline of this research to serve as a yardstick for creating awareness about radiation and its resulting effects.

  6. Stochastic Methods in Biology

    CERN Document Server

    Kallianpur, Gopinath; Hida, Takeyuki

    1987-01-01

    The use of probabilistic methods in the biological sciences has been so well established by now that mathematical biology is regarded by many as a distinct dis­ cipline with its own repertoire of techniques. The purpose of the Workshop on sto­ chastic methods in biology held at Nagoya University during the week of July 8-12, 1985, was to enable biologists and probabilists from Japan and the U. S. to discuss the latest developments in their respective fields and to exchange ideas on the ap­ plicability of the more recent developments in stochastic process theory to problems in biology. Eighteen papers were presented at the Workshop and have been grouped under the following headings: I. Population genetics (five papers) II. Measure valued diffusion processes related to population genetics (three papers) III. Neurophysiology (two papers) IV. Fluctuation in living cells (two papers) V. Mathematical methods related to other problems in biology, epidemiology, population dynamics, etc. (six papers) An important f...

  7. Relations between Intuitive Biological Thinking and Biological Misconceptions in Biology Majors and Nonmajors

    Science.gov (United States)

    Coley, John D.; Tanner, Kimberly

    2015-01-01

    Research and theory development in cognitive psychology and science education research remain largely isolated. Biology education researchers have documented persistent scientifically inaccurate ideas, often termed "misconceptions," among biology students across biological domains. In parallel, cognitive and developmental psychologists…

  8. Wireless Biological Electronic Sensors.

    Science.gov (United States)

    Cui, Yue

    2017-10-09

    The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

  9. Biological therapy of psoriasis

    Directory of Open Access Journals (Sweden)

    Sivamani Raja

    2010-01-01

    Full Text Available The treatment of psoriasis has undergone a revolution with the advent of biologic therapies, including infliximab, etanercept, adalimumab, efalizumab, and alefacept. These medications are designed to target specific components of the immune system and are a major technological advancement over traditional immunosuppressive medications. These usually being well tolerated are being found useful in a growing number of immune-mediated diseases, psoriasis being just one example. The newest biologic, ustekinumab, is directed against the p40 subunit of the IL-12 and IL-23 cytokines. It has provided a new avenue of therapy for an array of T-cell-mediated diseases. Biologics are generally safe; however, there has been concern over the risk of lymphoma with use of these agents. All anti-TNF-α agents have been associated with a variety of serious and "routine" opportunistic infections.

  10. Multiscale Biological Materials

    DEFF Research Database (Denmark)

    Frølich, Simon

    materials are characterized by their hierarchical and composite design, where features with sizes ranging from nanometers to centimeters provide the basis for the functionality of the material. Understanding of biological materials is, while very interesting from a basic research perspective, also valuable...... as inspiration for the development of new materials for medical and technological applications. In order to successfully mimic biological materials we must first have a thorough understanding of their design. As such, the purpose of the characterization of biological materials can be defined as the establishment...... mineral and the organic matrix in biomineralized calcite. High resolution powder diffraction was used to study how calcite in chalk, coccoliths, and mollusk shell is affected by the co-existent organic matrix. The calcified attachment organ in the saddle oyster, Anomia simplex serves as a brilliant...

  11. Topics in mathematical biology

    CERN Document Server

    Hadeler, Karl Peter

    2017-01-01

    This book analyzes the impact of quiescent phases on biological models. Quiescence arises, for example, when moving individuals stop moving, hunting predators take a rest, infected individuals are isolated, or cells enter the quiescent compartment of the cell cycle. In the first chapter of Topics in Mathematical Biology general principles about coupled and quiescent systems are derived, including results on shrinking periodic orbits and stabilization of oscillations via quiescence. In subsequent chapters classical biological models are presented in detail and challenged by the introduction of quiescence. These models include delay equations, demographic models, age structured models, Lotka-Volterra systems, replicator systems, genetic models, game theory, Nash equilibria, evolutionary stable strategies, ecological models, epidemiological models, random walks and reaction-diffusion models. In each case we find new and interesting results such as stability of fixed points and/or periodic orbits, excitability...

  12. Biological Soft Robotics.

    Science.gov (United States)

    Feinberg, Adam W

    2015-01-01

    In nature, nanometer-scale molecular motors are used to generate force within cells for diverse processes from transcription and transport to muscle contraction. This adaptability and scalability across wide temporal, spatial, and force regimes have spurred the development of biological soft robotic systems that seek to mimic and extend these capabilities. This review describes how molecular motors are hierarchically organized into larger-scale structures in order to provide a basic understanding of how these systems work in nature and the complexity and functionality we hope to replicate in biological soft robotics. These span the subcellular scale to macroscale, and this article focuses on the integration of biological components with synthetic materials, coupled with bioinspired robotic design. Key examples include nanoscale molecular motor-powered actuators, microscale bacteria-controlled devices, and macroscale muscle-powered robots that grasp, walk, and swim. Finally, the current challenges and future opportunities in the field are addressed.

  13. Informing biological design by integration of systems and synthetic biology.

    Science.gov (United States)

    Smolke, Christina D; Silver, Pamela A

    2011-03-18

    Synthetic biology aims to make the engineering of biology faster and more predictable. In contrast, systems biology focuses on the interaction of myriad components and how these give rise to the dynamic and complex behavior of biological systems. Here, we examine the synergies between these two fields. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Digital biology and chemistry.

    Science.gov (United States)

    Witters, Daan; Sun, Bing; Begolo, Stefano; Rodriguez-Manzano, Jesus; Robles, Whitney; Ismagilov, Rustem F

    2014-09-07

    This account examines developments in "digital" biology and chemistry within the context of microfluidics, from a personal perspective. Using microfluidics as a frame of reference, we identify two areas of research within digital biology and chemistry that are of special interest: (i) the study of systems that switch between discrete states in response to changes in chemical concentration of signals, and (ii) the study of single biological entities such as molecules or cells. In particular, microfluidics accelerates analysis of switching systems (i.e., those that exhibit a sharp change in output over a narrow range of input) by enabling monitoring of multiple reactions in parallel over a range of concentrations of signals. Conversely, such switching systems can be used to create new kinds of microfluidic detection systems that provide "analog-to-digital" signal conversion and logic. Microfluidic compartmentalization technologies for studying and isolating single entities can be used to reconstruct and understand cellular processes, study interactions between single biological entities, and examine the intrinsic heterogeneity of populations of molecules, cells, or organisms. Furthermore, compartmentalization of single cells or molecules in "digital" microfluidic experiments can induce switching in a range of reaction systems to enable sensitive detection of cells or biomolecules, such as with digital ELISA or digital PCR. This "digitizing" offers advantages in terms of robustness, assay design, and simplicity because quantitative information can be obtained with qualitative measurements. While digital formats have been shown to improve the robustness of existing chemistries, we anticipate that in the future they will enable new chemistries to be used for quantitative measurements, and that digital biology and chemistry will continue to provide further opportunities for measuring biomolecules, understanding natural systems more deeply, and advancing molecular and

  15. Biological radiolesions and repair

    International Nuclear Information System (INIS)

    Laskowski, W.

    1981-01-01

    In 7 chapters, the book answers the following questions: 1) What reactions are induced in biological matter by absorption of radiation energy. 2) In what parts of the cell do the radiation-induced reactions with detectable biological effects occur. 3) In which way are these cell components changed by different qualities of radiation. 4) What are the cell mechanisms by which radiation-induced changes can be repaired. 5) What is the importance of these repair processes for man, his life and evolution. At the end of each chapter, there is a bibliography of relevant publications in this field. (orig./MG) [de

  16. Neutron structural biology

    International Nuclear Information System (INIS)

    Niimura, Nobuo

    1999-01-01

    Neutron structural biology will be one of the most important fields in the life sciences which will interest human beings in the 21st century because neutrons can provide not only the position of hydrogen atoms in biological macromolecules but also the dynamic molecular motion of hydrogen atoms and water molecules. However, there are only a few examples experimentally determined at present because of the lack of neutron source intensity. Next generation neutron source scheduled in JAERI (Performance of which is 100 times better than that of JRR-3M) opens the life science of the 21st century. (author)

  17. Introduction to radiation biology

    International Nuclear Information System (INIS)

    Gensicke, F.

    1977-01-01

    The textbook is written with special regard to radiation protection of man. It shall enable the reader to assess the potential radiation risks to living organisms and lead him to an insight into radiation protection measures. The following topics are covered: physical fundamentals of ionizing radiations; physical and chemical fundamentals of biological radiation effects; radiation effects on cells, organs, organ systems, and whole animal organisms focussing on mammals and man; modification of radiation effects; chemical radiation protection; therapy of radiation injuries; radionuclide kinetics; biological radiation effects in connection with radiation hazards and with the limitation of radiation exposure. It is intended for vocational education of medical personnel

  18. Metamorphosis: Phases of UF{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, R.H. [Department of Energy, Oak Ridge, TN (United States)

    1991-12-31

    A 15-minute videotape is presented. The subject matter is 150 grams of UF{sub 6} sealed in a glass tube. Close-up views show the UF{sub 6} as phase changes are effected by the addition or removal of heat from the closed system. The solid-to-liquid transition is shown as heat is added, both slowly and rapidly. The solid phases which result from freezing and from desublimation are contrasted. In the solid state, uranium hexafluoride is a nearly-white, dense crystalline solid. The appearance of this solid depends on whether it is formed by freezing from the liquid or by desublimation from the vapor phase. If frozen from the liquid, the solid particles take the form of irregularly shaped coarse grains, while the solid product of desublimation tends to be a rather formless mass without individually distinguishable particles. The changes in state are presented in terms of the UF{sub 6} phase diagram.

  19. [Popular science: metamorphosis of knowledge in film].

    Science.gov (United States)

    Tanner, Jakob

    2009-01-01

    Far from being merely a medium of simplification and conveyance of scientific facts, motion pictures exhibit an important epistemic function. On the one hand, the medium film is itself a product of research in various fields, on the other hand, it retroacts on perception and problem-solving in science, thereby influencing and changing research practices. The paper aims at describing these reciprocal effects and synergies by discussing two examples: first by the film "The principles of Einstein's theory of relativity", first released in Germany in 1922, second by the film "Mathematical image of the struggle for life", produced in 1937 for the inauguration of the "Palace of discoveries" in Paris, demonstrating the latest developments in evolutionary theory. It becomes evident that picture media have the capacity to transform the symbolic dimension of things and bodies, thereby offering new access to reality, which not only fascinated the spectators, but also inspired scientific research.

  20. Metamorphosis in balanomorphan, pedunculated, and parasitic barnacles

    DEFF Research Database (Denmark)

    Høeg, Jens Thorvald; Maruzzo, Diego; Okano, Keiju

    2012-01-01

    irreversibly cemented itself to a substratum. In both Megabalanus rosa and Lepas, the settled cyprid first passes through a quiescent period of tissue reorganization, in which the body is raised into a position vertical to the substratum. In Lepas, this is followed by extension of the peduncle. In both Lepas...... larva to an attached suspension feeder (Thoracica) or an endoparasite (Rhizocephala). The cyprids and juveniles are so different in morphology that they are functionally incompatible. The drastic reorganization of the body implicated in the process can therefore only commence after the cyprid has...... and M. rosa, the juvenile must free itself from the cypris cuticle by an active process before it can extend the cirri for suspension feeding. In M. rosa, the juvenile performs intensely pulsating movements that result in shedding of the cypris carapace ~8¿h after settlement. Lepas sp. sheds the cypris...

  1. Metamorphosis in the cirripede crustacean Balanus amphitrite

    DEFF Research Database (Denmark)

    Maruzzo, Diego; Aldred, Nick; Clare, Anthony S.

    2012-01-01

    Stalked and acorn barnacles (Cirripedia Thoracica) have a complex life cycle that includes a free-swimming nauplius larva, a cypris larva and a permanently attached sessile juvenile and adult barnacle. The barnacle cyprid is among the most highly specialized of marine invertebrate larvae and its ...

  2. Normality. The Metamorphosis of an Immutable Concept

    Directory of Open Access Journals (Sweden)

    Alina Petra Marinescu

    2017-06-01

    Full Text Available Objectives: The present article discusses the realm of “normality” starting from the paradox standing behind the concept: a bench-mark always on the move. As a social concept, “normality” is based on the word “norm” understood as what is socially acceptable or desirable in terms of looks, attitudes or behaviours. Implications: The individual who doesn’t obey the rule is prone to being considered “deviant”. The present paper deals with the problematic brought by this labelling, with the subjective motivational process that leads to the social exclusion of the individuals who don’t behave in the spirit of the accepted norm and also with the methods people make use of in order to cope with their new status. Value: “Normality”, a concept apparently denoting stability, has to adapt to various contexts and this thesis seems puzzling. The first and most important condition is that of the highly subjective human nature that comes in contradiction with stability and perfection – features defining the Latin “norma”, meaning “right” angle. And still individuals themselves are the ones creating and imposing social norms. Approach: In order to try to find an explanation, the paper makes use of the realm of deviance studies and presents the reader with some paradoxical examples as the biblical one where the ejection from Paradise was caused by the crossing of a norm whereas the word “normality” or “normal” cannot be found in the Christian Holy Book. To further picture the dynamics of “normality”, a case study analysing the women’s social status in three different centuries as reflected in painting was included in the article.

  3. The Current Metamorphosis of Instrumental Rationality

    Czech Academy of Sciences Publication Activity Database

    Hauser, Michael

    2014-01-01

    Roč. 4, č. 7 (2014), s. 517-523 ISSN 2159-5321 Institutional support: RVO:67985955 Keywords : instrumental reason * Lukács * Adorno * Horkheimer * postmodern pluralism * capitalism Subject RIV: AA - Philosophy ; Religion

  4. Romania: Childbearing metamorphosis within a changing context

    Directory of Open Access Journals (Sweden)

    Christin Schröder

    2008-07-01

    Full Text Available In 1989, the socialist regime in Romania collapsed and the state's coercive pro-natalist policy ended. Since then, fertility has gone through major changes, namely, a massive reduction in fertility and important structural changes: birth postponement, an end to universal childbearing, and the emergence of non-marital births. Family formation has been postponed, but a pattern of early marriage still persists compared to other European countries. Although unmarried cohabitation is rising, it is rarely seen as an alternative to marriage. Modern contraceptive methods are being used increasingly, but traditional contraceptive methods continue to be widespread. Abortion, which was re-legalized in 1989 and made available after two decades of prohibition, has been practiced extensively ever since, especially after first birth. Romanians in 2004 continue to have a universal preference for parenting. However, the preference for the two-child family has declined and the desire for a larger family has become the exception. The transformation of the socialist regime into a democratic society with a market economy generated a socio-economic crisis, and the majority of social benefits have therefore been oriented towards alleviating poverty. Other social policies, including those affecting the family, were redefined. However, fewer funds were made available than for those geared to promote economic development or reduce poverty and, as a consequence, their impact on childbearing has been small.

  5. Chameleon or Phoenix: The Metamorphosis of TAFE.

    Science.gov (United States)

    Anderson, Damon

    1998-01-01

    Examines aspects of the history of technical and vocational education (TAFE) in Australia: technical education system in Victoria; dissolution of the binary system in higher education; and new instructional discourses and practices shaping TAFE. Speculates on the potential reemergence of the binary system and future prospects for TAFE. (SK)

  6. Metamorphosis and the Management of Change

    Science.gov (United States)

    Smith, Richard

    2016-01-01

    Talk of educational reform and of the importance of "the management of change" in education and elsewhere is still in vogue. However it often seems concerned to persuade us that if we engage fully with change rather than resisting it we will find our lives more meaningful, thus omitting the important matter of the goal of the change in…

  7. Fermion boson metamorphosis in field theory

    International Nuclear Information System (INIS)

    Ha, Y.K.

    1982-01-01

    In two-dimensional field theories many features are especially transparent if the Fermi fields are represented by non-local expressions of the Bose fields. Such a procedure is known as boson representation. Bilinear quantities appear in the Lagrangian of a fermion theory transform, however, as simple local expressions of the bosons so that the resulting theory may be written as a theory of bosons. Conversely, a theory of bosons may be transformed into an equivalent theory of fermions. Together they provide a basis for generating many interesting equivalences between theories of different types. In the present work a consistent scheme for constructing a canonical Fermi field in terms of a real scalar field is developed and such a procedure is valid and consistent with the tenets of quantum field theory is verified. A boson formulation offers a unifying theme in understanding the structure of many theories. This is illustrated by the boson formulation of a multifermion theory with chiral and internal symmetries. The nature of dynamical generation of mass when the theory undergoes boson transmutation and the preservation of continuous chiral symmetry in the massive case are examined. The dynamics of the system depends to a great extent on the specific number of fermions and different models of the same system can have very different properties. Many unusual symmetries of the fermion theory, such as hidden symmetry, duality and triality symmetries, are only manifest in the boson formulation. The underlying connections between some models with U(N) internal symmetry and another class of fermion models built with Majorana fermions which have O(2N) internal symmetry are uncovered

  8. 7th Annual Systems Biology Symposium: Systems Biology and Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Galitski, Timothy P.

    2008-04-01

    Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering are now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."

  9. The hypothalamic-pituitary-thyroid axis and biological rhythms: The discovery of TSH's unexpected role using animal models.

    Science.gov (United States)

    Ikegami, Keisuke; Yoshimura, Takashi

    2017-10-01

    Thyroid hormones (TH) are important for development, growth, and metabolism. It is also clear that the synthesis and secretion of TH are regulated by the hypothalamic-pituitary-thyroid (HPT) axis. Animal models have helped advance our understanding of the roles and regulatory mechanisms of TH. The animals' bodies develop through coordinated timing of cell division and differentiation. Studies of frog metamorphosis led to the discovery of TH and their role in development. However, to adapt to rhythmic environmental changes, animals also developed various endocrine rhythms. Studies of rodents clarified the neural and molecular mechanisms underlying the circadian regulation of the HPT axis. Moreover, birds have a sophisticated seasonal adaptation mechanism, and recent studies of quail revealed unexpected roles for thyroid-stimulating hormone (TSH) and TH in the seasonal regulation of reproduction. Interestingly, this mechanism is conserved in mammals. Thus, we review how animal studies have shaped our general understanding of the HPT axis in relation to biological rhythms. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Biology of a deep-water sea anemone (Anthozoa: Actiniidae) from eastern Canada: Spawning, development, and growth

    Science.gov (United States)

    Mercier, Annie; Baillon, Sandrine; Daly, Marymegan; Macrander, Jason; Hamel, Jean-François

    2017-03-01

    Knowledge of the general biology and reproductive ecology of deep-water species can help predict their resilience to environmental and anthropogenic disturbances. The present study centers on live specimens of a deep-water sea anemone which were collected at bathyal depths between 1100 and 1400 m and kept in a mesocosm for over 6 years. Morphology and DNA sequencing confirmed that the species belongs to the genus Urticina. Male and female (9-10 cm pedal disk diameter, 90 tentacles) spawned 4 years post collection, in early spring (March). Both sexes released gametes through the mouth. The negatively buoyant oocytes (550-600 μm in diameter) quickly settled on the rocks and soft sediments surrounding the female. Lecithotrophic embryonic and larval development occurred on the substratum. Fully developed planula larvae were detected after 17-21 days. Planulae started to crawl and swim around but remained demersal. Metamorphosis and settlement occurred after 30-35 days, exclusively on hard substrata and preferentially on undersurfaces. Offspring grew slowly, developing 8 tentacles after 5 months and 24 tentacles after 12 months (3-4 mm pedal disk diameter). After 2.6 years of growth, the captive-born sea anemones reached 12-16 mm in pedal disk diameter and possessed 48-54 tentacles.

  11. Sequencing and structural homology modeling of the ecdysone receptor in two chrysopids used in biological control of pest insects.

    Science.gov (United States)

    Zotti, Moises João; Christiaens, Olivier; Rougé, Pierre; Grutzmacher, Anderson Dionei; Zimmer, Paulo Dejalma; Smagghe, Guy

    2012-04-01

    In insects, the process of molting and metamorphosis are mainly regulated by a steroidal hormone 20-hydroxyecdysone (20E) and its analogs (ecdysteroids) that specifically bind to the ecdysone receptor ligand-binding domain (EcR-LBD). Currently, several synthetic non-steroidal ecdysone agonists, including tebufenozide, are commercially available as insecticides. Tebufenozide exerts its activity by binding to the 20E-binding site and thus activating EcR permanently. It appears that subtle differences in the architecture among LBDs may underpin the differential binding affinity of tebufenozide across taxonomic orders. In brief, first we demonstrated the harmlessness of tebufenozide towards Chrysoperla externa (Ce). Then, a molecular analysis of EcR-LBD of two neuropteran insects Chrysoperla carnea and Ce was presented. Finally, we constructed a chrysopid in silico homology model docked ponasterone A (PonA) and tebufenozide into the binding pocket and analyzed the amino acids indentified as critical for binding to PonA and tebufenozide. Due to a restrict extent in the cavity at the bottom of the ecdysone-binding pocket a steric clash occurred upon docking of tebufenozide. The absence of harm biological effect and the docking results suggest that tebufenozide is prevented of any deleterious effects on chrysopids.

  12. Systems biology in animal sciences

    NARCIS (Netherlands)

    Woelders, H.; Pas, te M.F.W.; Bannink, A.; Veerkamp, R.F.; Smits, M.A.

    2011-01-01

    Systems biology is a rapidly expanding field of research and is applied in a number of biological disciplines. In animal sciences, omics approaches are increasingly used, yielding vast amounts of data, but systems biology approaches to extract understanding from these data of biological processes

  13. Coordination Compounds in Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 6. Coordination Compounds in Biology - The Chemistry of Vitamin B12 and Model Compounds. K Hussian Reddy. General Article Volume 4 Issue 6 June 1999 pp 67-77 ...

  14. Fusion of biological membranes

    Indian Academy of Sciences (India)

    small hemifusion diaphragm. To obtain a direct view of the fusion process, we have carried out extensive simulations of two bilayers, composed of block copolymers, which are immersed in a solvent which favors one of the blocks. As in the biological case, the membranes are placed under tension. This is essential as fusion ...

  15. Biological dose estimation

    African Journals Online (AJOL)

    a radiation. •. In exposure. Biological dose estimation involving low-dose. S. JANSEN, G. J. VAN HUYSSTEEN. Summary. Blood specimens were collected from 8 people 18 days after they had been accidentally exposed to a 947,2 GBq iridium-. 192 source during industrial application. The equivalent whole-body dose ...

  16. Coordination Compounds in Biology

    Indian Academy of Sciences (India)

    Coordination Compounds in Biology equatorial ligand, there are two axial ligands in most B. 12 derivatives. Derivatives of B12. The various derivatives of B. 12 result most commonly from changes in the axial ligands bound to cobalt. Often it is convenient to draw a greatly abbreviated structure for a B. 12 molecule using a ...

  17. Tree biology and dendrochemistry

    Science.gov (United States)

    Kevin T. Smith; Walter C. Shortle

    1996-01-01

    Dendrochemistry, the interpretation of elemental analysis of dated tree rings, can provide a temporal record of environmental change. Using the dendrochemical record requires an understanding of tree biology. In this review, we pose four questions concerning assumptions that underlie recent dendrochemical research: 1) Does the chemical composition of the wood directly...

  18. Aquatic biology studies

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Aquatic biology studies focused on studying the hydrothermal effects of Par Pond reservoir on periphyton, plankton, zooplankton, macrophytes, human pathogens, and microbial activity; the variability between the artificial streams of the Flowing Streams Laboratory and Upper Three Runs Creek; and the bacterial production of methane in Savannah River Plant aquatic systems

  19. Next-generation biology

    DEFF Research Database (Denmark)

    Rodrigues da Fonseca, Rute Andreia; Albrechtsen, Anders; Themudo, Goncalo Espregueira Cruz

    2016-01-01

    we present an overview of the current sequencing technologies and the methods used in typical high-throughput data analysis pipelines. Subsequently, we contextualize high-throughput DNA sequencing technologies within their applications in non-model organism biology. We include tips regarding managing...

  20. Radiation biology at CRNL

    International Nuclear Information System (INIS)

    Myers, D.K.

    1986-01-01

    This paper gives a broad overview of radiation biology at Chalk River Nuclear Laboratories (CRNL). The research group consists of 8 professionals and approximately 12 support staff. Objectives of the group are listed. Current research programs discussed are: 1) recombinant dna technology; 2) the hyperthermia program; 3) cancer-prone families; 4) animal studies; and 5) assessment of radiation hazards

  1. Biological response modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Weller, R.E.

    1991-10-01

    Much of what used to be called immunotherapy is now included in the term biological response modifiers. Biological response modifiers (BRMs) are defined as those agents or approaches that modify the relationship between the tumor and host by modifying the host's biological response to tumor cells with resultant therapeutic effects.'' Most of the early work with BRMs centered around observations of spontaneous tumor regression and the association of tumor regression with concurrent bacterial infections. The BRM can modify the host response in the following ways: Increase the host's antitumor responses through augmentation and/or restoration of effector mechanisms or mediators of the host's defense or decrease the deleterious component by the host's reaction; Increase the host's defenses by the administration of natural biologics (or the synthetic derivatives thereof) as effectors or mediators of an antitumor response; Augment the host's response to modified tumor cells or vaccines, which might stimulate a greater response by the host or increase tumor-cell sensitivity to an existing response; Decrease the transformation and/or increase differentiation (maturation) of tumor cells; or Increase the ability of the host to tolerate damage by cytotoxic modalities of cancer treatment.

  2. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 2. Evolutionary Biology Today - What do Evolutionary Biologists do? Amitabh Joshi. Series Article Volume 8 Issue 2 February 2003 pp 6-18. Fulltext. Click here to view fulltext PDF. Permanent link:

  3. Cryptochromes and Biological Clocks

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 9. Cryptochromes and Biological Clocks. V R Bhagwat. General Article Volume 7 Issue 9 September 2002 pp 36-48. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/007/09/0036-0048. Keywords.

  4. Situeret interesse i biologi

    DEFF Research Database (Denmark)

    Dohn, Niels Bonderup

    2006-01-01

    Interesse hævdes at spille en vigtig rolle i læring. Med udgangspunkt i interesseteori og situeret læring har jeg foretaget et studium i en gymnasieklasse med biologi på højt niveau, med henblik på at identificere hvilke forhold der har betydning for hvad der fanger elevers interesse. Jeg har...

  5. Fusion of biological membranes

    Indian Academy of Sciences (India)

    Logo of the Indian Academy of Sciences. Indian Academy of ... Home; Journals; Pramana – Journal of Physics; Volume 64; Issue 6. Fusion of biological ... The process of membrane fusion has been examined by Monte Carlo simulation, and is found to be very different than the conventional picture. The differences in ...

  6. Plant Systems Biology (editorial)

    Science.gov (United States)

    In June 2003, Plant Physiology published an Arabidopsis special issue devoted to plant systems biology. The intention of Natasha Raikhel and Gloria Coruzzi, the two editors of this first-of-its-kind issue, was ‘‘to help nucleate this new effort within the plant community’’ as they considered that ‘‘...

  7. Evolution, Entropy, & Biological Information

    Science.gov (United States)

    Peterson, Jacob

    2014-01-01

    A logical question to be expected from students: "How could life develop, that is, change, evolve from simple, primitive organisms into the complex forms existing today, while at the same time there is a generally observed decline and disorganization--the second law of thermodynamics?" The explanations in biology textbooks relied upon by…

  8. Water pollution biology

    Energy Technology Data Exchange (ETDEWEB)

    Mason, C.F. [University of Essex, Colchester (United Kingdom). Dept. of Biology

    1996-12-31

    Chapter 4 of this book describes the effects of major types of pollutants on aquatic life. These are: organic pollution, eutrophication, acidification, toxic chemicals, oil, and radioactivity. The review includes an description of some of the methods of assessing the biological impacts of pollution. 50 refs., 8 figs., 3 tabs.

  9. Systems biology at work

    NARCIS (Netherlands)

    Martins Dos Santos, V.A.P.; Damborsky, J.

    2010-01-01

    In his editorial overview for the 2008 Special Issue on this topic, the late Jaroslav Stark pointedly noted that systems biology is no longer a niche pursuit, but a recognized discipline in its own right “noisily” coming of age [1]. Whilst general underlying principles and basic techniques are now

  10. Diversity in Biological Molecules

    Science.gov (United States)

    Newbury, H. John

    2010-01-01

    One of the striking characteristics of fundamental biological processes, such as genetic inheritance, development and primary metabolism, is the limited amount of variation in the molecules involved. Natural selective pressures act strongly on these core processes and individuals carrying mutations and producing slightly sub-optimal versions of…

  11. Biologically inspired intelligent robots

    Science.gov (United States)

    Bar-Cohen, Yoseph; Breazeal, Cynthia

    2003-07-01

    Humans throughout history have always sought to mimic the appearance, mobility, functionality, intelligent operation, and thinking process of biological creatures. This field of biologically inspired technology, having the moniker biomimetics, has evolved from making static copies of human and animals in the form of statues to the emergence of robots that operate with realistic behavior. Imagine a person walking towards you where suddenly you notice something weird about him--he is not real but rather he is a robot. Your reaction would probably be "I can't believe it but this robot looks very real" just as you would react to an artificial flower that is a good imitation. You may even proceed and touch the robot to check if your assessment is correct but, as oppose to the flower case, the robot may be programmed to respond physical and verbally. This science fiction scenario could become a reality as the current trend continues in developing biologically inspired technologies. Technology evolution led to such fields as artificial muscles, artificial intelligence, and artificial vision as well as biomimetic capabilities in materials science, mechanics, electronics, computing science, information technology and many others. This paper will review the state of the art and challenges to biologically-inspired technologies and the role that EAP is expected to play as the technology evolves.

  12. Biology=Sinh Vat.

    Science.gov (United States)

    Hung, Nguyen Manh, Ed.

    This volume contains 32 biology self-study learning packets designed primarily for Indochinese students in grades 9 to 12. The materials could be used by "English as a Second Language" teachers who may/may not speak one of the Indochinese languages, or by mainstream teachers who have a number of low-English-proficiency Indochinese students in…

  13. Allometry and astro biology

    International Nuclear Information System (INIS)

    Sertorio, L.; Renda, E.

    2009-01-01

    Allometric laws expressing power and lifespan as a function of mass for both inorganic and organic systems are analyzed. This way of dealing with complexity unveils striking analogies between domains of science that we are used to consider conceptually irreducible to each other and therefore can be considered a new vision of astro biology.

  14. Molecular Biology of Medulloblastoma

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-12-01

    Full Text Available Current methods of diagnosis and treatment of medulloblastoma, and the influence of new biological advances in the development of more effective and less toxic therapies are reviewed by researchers at Children’s National Medical Center, The George Washington University, Washington, DC.

  15. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Amitabh Joshi studies and teaches evolutionary genetics and population ecology at the Jawaharlal. Nehru Centre for Advanced. Scientific Research,. Bangalore. His current research interests are in life- history evolution, the evolutionary genetics of biological clocks, and small population and meta population dynamics.

  16. Antiprotons get biological

    CERN Multimedia

    2003-01-01

    After its final run in September, the first results of the Antiproton Cell Experiment (ACE) look very promising. It was the first experiment to take data on the biological effects of antiproton beams to evaluate the potential of antiprotons in radiation therapy.

  17. Bayes in biological anthropology.

    Science.gov (United States)

    Konigsberg, Lyle W; Frankenberg, Susan R

    2013-12-01

    In this article, we both contend and illustrate that biological anthropologists, particularly in the Americas, often think like Bayesians but act like frequentists when it comes to analyzing a wide variety of data. In other words, while our research goals and perspectives are rooted in probabilistic thinking and rest on prior knowledge, we often proceed to use statistical hypothesis tests and confidence interval methods unrelated (or tenuously related) to the research questions of interest. We advocate for applying Bayesian analyses to a number of different bioanthropological questions, especially since many of the programming and computational challenges to doing so have been overcome in the past two decades. To facilitate such applications, this article explains Bayesian principles and concepts, and provides concrete examples of Bayesian computer simulations and statistics that address questions relevant to biological anthropology, focusing particularly on bioarchaeology and forensic anthropology. It also simultaneously reviews the use of Bayesian methods and inference within the discipline to date. This article is intended to act as primer to Bayesian methods and inference in biological anthropology, explaining the relationships of various methods to likelihoods or probabilities and to classical statistical models. Our contention is not that traditional frequentist statistics should be rejected outright, but that there are many situations where biological anthropology is better served by taking a Bayesian approach. To this end it is hoped that the examples provided in this article will assist researchers in choosing from among the broad array of statistical methods currently available. Copyright © 2013 Wiley Periodicals, Inc.

  18. Entropy in Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 9. Entropy in Biology. Jayant B Udgaonkar. General Article Volume 6 Issue 9 September 2001 pp 61-66. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/006/09/0061-0066. Author Affiliations.

  19. Biological science in conservation

    Science.gov (United States)

    David M. Johns

    2000-01-01

    Large-scale wildlands reserve systems offer one of the best hopes for slowing, if not reversing, the loss of biodiversity and wilderness. Establishing such reserves requires both sound biology and effective advocacy. Attempts by The Wildlands Project and its cooperators to meld science and advocacy in the service of conservation is working, but is not without some...

  20. Biological trade and markets.

    Science.gov (United States)

    Hammerstein, Peter; Noë, Ronald

    2016-02-05

    Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

  1. CASPIAN BIOLOGICAL RESOURCES

    Directory of Open Access Journals (Sweden)

    M. K. Guseynov

    2015-01-01

    Full Text Available Aim. We present the data on the biological resources of the Caspian Sea, based on the analysis of numerous scientific sources published between years of 1965 and 2011. Due to changes in various biotic and abiotic factors we find it important to discuss the state of the major groups of aquatic biocenosis including algae, crayfish, shrimp, pontogammarus, fish and Caspian seal. Methods. Long-term data has been analyzed on the biology and ecology of the main commercial fish stocks and their projected catches for qualitative and quantitative composition, abundance and biomass of aquatic organisms that make up the food base for fish. Results and discussion. It has been found that the widespread commercial invertebrates in the Caspian Sea are still poorly studied; their stocks are not identified and not used commercially. There is a great concern about the current state of the main commercial fish stocks of the Caspian Sea. A critical challenge is to preserve the pool of biological resources and the restoration of commercial stocks of Caspian fish. For more information about the state of the marine ecosystem in modern conditions, expedition on Caspian Sea should be carried out to study the hydrochemical regime and fish stocks, assessment of sturgeon stocks, as well as the need to conduct sonar survey for sprat stocks. Conclusions. The main condition for preserving the ecosystem of the Caspian Sea and its unique biological resources is to develop and apply environmentally-friendly methods of oil, issuing concerted common fisheries rules in various regions of theCaspian Sea, strengthening of control for sturgeon by all Caspian littoral states. The basic principle of the protection of biological resources is their rational use, based on the preservation of optimal conditions of their natural or artificial reproduction. 

  2. Integrating Concepts in Biology

    Science.gov (United States)

    Luckie, Douglas B; Hoskinson, Anne-Marie; Griffin, Caleigh E; Hess, Andrea L; Price, Katrina J; Tawa, Alex; Thacker, Samantha M

    2017-01-01

    The purpose of this study was to examine the educational impact of an intervention, the inquiry-focused textbook Integrating Concepts in Biology ( ICB ), when used in a yearlong introductory biology course sequence. Student learning was evaluated using three published instruments: 1) The Biology Concept Inventory probed depth of student mastery of fundamental concepts in organismal and cellular topics when confronting misconceptions as distractors. ICB students had higher gains in all six topic categories (+43% vs. peers overall, p concepts, like experts. The frequency with which ICB students connected deep-concept pairs, or triplets, was similar to peers; but deep understanding of structure/function was much higher (for pairs: 77% vs. 25%, p < 0.01). 3) A content-focused Medical College Admission Test (MCAT) posttest compared ICB student content knowledge with that of peers from 15 prior years. Historically, MCAT performance for each semester ranged from 53% to 64%; the ICB cohort scored 62%, in the top quintile. Longitudinal tracking in five upper-level science courses the following year found ICB students outperformed peers in physiology (85% vs. 80%, p < 0.01). © 2017 D. B. Luckie et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. Biological Threats Detection Technologies

    International Nuclear Information System (INIS)

    Bartoszcze, M.

    2007-01-01

    Among many decisive factors, which can have the influence on the possibility of decreases the results of use biological agents should be mentioned obligatory: rapid detection and identification of biological factor used, the proper preventive treatment and the medical management. The aims of identification: to identify the factor used, to estimate the area of contamination, to evaluate the possible countermeasure efforts (antibiotics, disinfectants) and to assess the effectiveness of the decontamination efforts (decontamination of the persons, equipment, buildings, environment etc.). The objects of identification are: bacteria and bacteria's spores, viruses, toxins and genetically modified factors. The present technologies are divided into: based on PCR techniques (ABI PRISM, APSIS, BIOVERIS, RAPID), immuno (BADD, RAMP, SMART) PCR and immuno techniques (APDS, LUMINEX) and others (BDS2, LUNASCAN, MALDI). The selected technologies assigned to field conditions, mobile and stationary laboratories will be presented.(author)

  4. [Cell biology and cosmetology].

    Science.gov (United States)

    Traniello, S; Cavalletti, T

    1991-01-01

    Cellular biology can become the natural support of research in the field of cosmetics because it is able to provide alternative experimental models which can partially replace the massive use of laboratory animals. Cultures of human skin cells could be used in tests investigating irritation of the skin. We have developed an "in vitro" experimental model that allows to evaluate the damage caused by the free radicals to the fibroblasts in culture and to test the protective action of the lipoaminoacids. Experimenting on human cell cultures presents the advantage of eliminating the extrapolation between the different species, of allowing a determination of the biological action of a substance and of evaluating its dose/response effect. This does not mean that "in vitro" experimenting could completely replace experimenting on living animals, but the "in vitro" model can be introduced in the realisation of preliminary screenings.

  5. Topology in Molecular Biology

    CERN Document Server

    Monastyrsky, Michail Ilych

    2007-01-01

    The book presents a class of new results in molecular biology for which topological methods and ideas are important. These include: the large-scale conformation properties of DNA; computational methods (Monte Carlo) allowing the simulation of large-scale properties of DNA; the tangle model of DNA recombination and other applications of Knot theory; dynamics of supercoiled DNA and biocatalitic properties of DNA; the structure of proteins; and other very recent problems in molecular biology. The text also provides a short course of modern topology intended for the broad audience of biologists and physicists. The authors are renowned specialists in their fields and some of the new results presented here are documented for the first time in monographic form.

  6. The Biological Universe

    Science.gov (United States)

    Dick, Steven J.

    1999-12-01

    Throughout the twentieth century, from the furor over Percival Lowell's claim of canals on Mars to the sophisticated Search for Extraterrestrial Intelligence, otherworldly life has often intrigued and occasionally consumed science and the public. The Biological Universe provides a rich and colorful history of the attempts during the twentieth century to answer questions such as whether "biological law" reigns throughout the universe and whether there are other histories, religions, and philosophies outside those on Earth. Covering a broad range of topics, including the search for life in the solar system, the origins of life, UFOs, and aliens in science fiction, Steven J. Dick shows how the concept of extraterrestrial intelligence is a world view of its own, a "biophysical cosmology" that seeks confirmation no less than physical views of the universe. This book will fascinate astronomers, historians of science, biochemists, and science fiction readers.

  7. Quantum physics meets biology.

    Science.gov (United States)

    Arndt, Markus; Juffmann, Thomas; Vedral, Vlatko

    2009-12-01

    Quantum physics and biology have long been regarded as unrelated disciplines, describing nature at the inanimate microlevel on the one hand and living species on the other hand. Over the past decades the life sciences have succeeded in providing ever more and refined explanations of macroscopic phenomena that were based on an improved understanding of molecular structures and mechanisms. Simultaneously, quantum physics, originally rooted in a world-view of quantum coherences, entanglement, and other nonclassical effects, has been heading toward systems of increasing complexity. The present perspective article shall serve as a "pedestrian guide" to the growing interconnections between the two fields. We recapitulate the generic and sometimes unintuitive characteristics of quantum physics and point to a number of applications in the life sciences. We discuss our criteria for a future "quantum biology," its current status, recent experimental progress, and also the restrictions that nature imposes on bold extrapolations of quantum theory to macroscopic phenomena.

  8. Multiplexed Engineering in Biology.

    Science.gov (United States)

    Rogers, Jameson K; Church, George M

    2016-03-01

    Biotechnology is the manufacturing technology of the future. However, engineering biology is complex, and many possible genetic designs must be evaluated to find cells that produce high levels of a desired drug or chemical. Recent advances have enabled the design and construction of billions of genetic variants per day, but evaluation capacity remains limited to thousands of variants per day. Here we evaluate biological engineering through the lens of the design–build–test cycle framework and highlight the role that multiplexing has had in transforming the design and build steps. We describe a multiplexed solution to the ‘test’ step that is enabled by new research. Achieving a multiplexed test step will permit a fully multiplexed engineering cycle and boost the throughput of biobased product development by up to a millionfold.

  9. Biological Correlates of Empathy

    Directory of Open Access Journals (Sweden)

    E. Timucin Oral

    2010-04-01

    Full Text Available Empathy can be defined as the capacity to know emotionally what another is experiencing from within the frame of reference of that other person and the capacity to sample the feelings of another or it can be metaphorized as to put oneself in another’s shoes. Although the concept of empathy was firstly described in psychological theories, researches studying the biological correlates of psychological theories have been increasing recently. Not suprisingly, dinamically oriented psychotherapists Freud, Kohut, Basch and Fenichel had suggested theories about the biological correlates of empathy concept and established the basis of this modality decades ago. Some other theorists emphasized the importance of empathy in the early years of lifetime regarding mother-child attachment in terms of developmental psychology and investigated its role in explanation of psychopathology. The data coming from some of the recent brain imaging and animal model studies also seem to support these theories. Although increased activity in different brain regions was shown in many of the brain imaging studies, the role of cingulate cortex for understanding mother-child relationship was constantly emphasized in nearly all of the studies. In addition to these studies, a group of Italian scientists has defined a group of neurons as “mirror neurons” in their studies observing rhesus macaque monkeys. Later, they also defined mirror neurons in human studies, and suggested them as “empathy neurons”. After the discovery of mirror neurons, the hopes of finding the missing part of the puzzle for understanding the biological correlates of empathy raised again. Although the roles of different biological parameters such as skin conductance and pupil diameter for defining empathy have not been certain yet, they are going to give us the opportunity to revise the inconsistent basis of structural validity in psychiatry and to stabilize descriptive validity. In this review, the

  10. Integrative radiation systems biology

    International Nuclear Information System (INIS)

    Unger, Kristian

    2014-01-01

    Maximisation of the ratio of normal tissue preservation and tumour cell reduction is the main concept of radiotherapy alone or combined with chemo-, immuno- or biologically targeted therapy. The foremost parameter influencing this ratio is radiation sensitivity and its modulation towards a more efficient killing of tumour cells and a better preservation of normal tissue at the same time is the overall aim of modern therapy schemas. Nevertheless, this requires a deep understanding of the molecular mechanisms of radiation sensitivity in order to identify its key players as potential therapeutic targets. Moreover, the success of conventional approaches that tried to statistically associate altered radiation sensitivity with any molecular phenotype such as gene expression proofed to be somewhat limited since the number of clinically used targets is rather sparse. However, currently a paradigm shift is taking place from pure frequentistic association analysis to the rather holistic systems biology approach that seeks to mathematically model the system to be investigated and to allow the prediction of an altered phenotype as the function of one single or a signature of biomarkers. Integrative systems biology also considers the data from different molecular levels such as the genome, transcriptome or proteome in order to partially or fully comprehend the causal chain of molecular mechanisms. An example for the application of this concept currently carried out at the Clinical Cooperation Group “Personalized Radiotherapy in Head and Neck Cancer” of the Helmholtz-Zentrum München and the LMU Munich is described. This review article strives for providing a compact overview on the state of the art of systems biology, its actual challenges, potential applications, chances and limitations in radiation oncology research working towards improved personalised therapy concepts using this relatively new methodology

  11. Elements in biological AMS

    International Nuclear Information System (INIS)

    Vogel, J.S.; McAninch, J.; Freeman, S.

    1996-08-01

    AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. 14 C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth's biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed

  12. Dominating biological networks.

    Directory of Open Access Journals (Sweden)

    Tijana Milenković

    Full Text Available Proteins are essential macromolecules of life that carry out most cellular processes. Since proteins aggregate to perform function, and since protein-protein interaction (PPI networks model these aggregations, one would expect to uncover new biology from PPI network topology. Hence, using PPI networks to predict protein function and role of protein pathways in disease has received attention. A debate remains open about whether network properties of "biologically central (BC" genes (i.e., their protein products, such as those involved in aging, cancer, infectious diseases, or signaling and drug-targeted pathways, exhibit some topological centrality compared to the rest of the proteins in the human PPI network.To help resolve this debate, we design new network-based approaches and apply them to get new insight into biological function and disease. We hypothesize that BC genes have a topologically central (TC role in the human PPI network. We propose two different concepts of topological centrality. We design a new centrality measure to capture complex wirings of proteins in the network that identifies as TC those proteins that reside in dense extended network neighborhoods. Also, we use the notion of domination and find dominating sets (DSs in the PPI network, i.e., sets of proteins such that every protein is either in the DS or is a neighbor of the DS. Clearly, a DS has a TC role, as it enables efficient communication between different network parts. We find statistically significant enrichment in BC genes of TC nodes and outperform the existing methods indicating that genes involved in key biological processes occupy topologically complex and dense regions of the network and correspond to its "spine" that connects all other network parts and can thus pass cellular signals efficiently throughout the network. To our knowledge, this is the first study that explores domination in the context of PPI networks.

  13. Mammalian Synthetic Biology

    OpenAIRE

    Martella, Andrea; Pollard, Steven M; Dai, Junbiao; Cai, Yizhi

    2016-01-01

    The enabling technologies of synthetic biology are opening up new opportunities for engineering and enhancement of mammalian cells. This will stimulate diverse applications in many life science sectors such as regenerative medicine, development of biosensing cell lines, therapeutic protein production, and generation of new synthetic genetic regulatory circuits. Harnessing the full potential of these new engineering-based approaches requires the design and assembly of large DNA constructs-pote...

  14. Reevaluating synthesis by biology.

    Science.gov (United States)

    Yadav, Vikramaditya G; Stephanopoulos, Gregory

    2010-06-01

    The two cornerstones of synthetic biology are the introduction of the new technology of chemical DNA synthesis and its subsequent emphasis on the use of standardized biological parts in the construction of genetic systems aimed at eliciting of desired cellular behavior. A number of high-impact applications have been proposed for this technology, notable among them being the biological synthesis of valuable compounds for chemical or pharmaceutical use. To this end, synthetic biologists propose assembling metabolic pathways in toto by combining genes isolated from a variety of sources. While pathway construction is similar to approaches established long ago by Metabolic Engineering, the two methods deviate significantly when it comes to pathway optimization. Synthetic biologists opt for gene-combinatorial methods whereby large numbers of pathways, comprising several combinations of genes from different sources, and their mutants, are evaluated in search for an optimal pathway configuration. Metabolic engineering, on the contrary, aims to optimize pathways by tuning the activity of the intermediate reaction steps. Both, rational methods based on kinetics and regulation, as well as combinatorial methods, typically in this order, are used to this end. We argue that a systematic approach consisting of fine-tuning the properties of individual pathway components, prominently enzymes, is a superior strategy to searches spanning large genetic spaces in engineering optimal microbes for the production of chemical and pharmaceutical products. Copyright 2010 Elsevier Ltd. All rights reserved.

  15. Biologics for tendon repair☆

    Science.gov (United States)

    Docheva, Denitsa; Müller, Sebastian A.; Majewski, Martin; Evans, Christopher H.

    2015-01-01

    Tendon injuries are common and present a clinical challenge to orthopedic surgery mainly because these injuries often respond poorly to treatment and require prolonged rehabilitation. Therapeutic options used to repair ruptured tendons have consisted of suture, autografts, allografts, and synthetic prostheses. To date, none of these alternatives has provided a successful long-term solution, and often the restored tendons do not recover their complete strength and functionality. Unfortunately, our understanding of tendon biology lags far behind that of other musculoskeletal tissues, thus impeding the development of new treatment options for tendon conditions. Hence, in this review, after introducing the clinical significance of tendon diseases and the present understanding of tendon biology, we describe and critically assess the current strategies for enhancing tendon repair by biological means. These consist mainly of applying growth factors, stem cells, natural biomaterials and genes, alone or in combination, to the site of tendon damage. A deeper understanding of how tendon tissue and cells operate, combined with practical applications of modern molecular and cellular tools could provide the long awaited breakthrough in designing effective tendon-specific therapeutics and overall improvement of tendon disease management. PMID:25446135

  16. Neutrons in biology

    International Nuclear Information System (INIS)

    Funahashi, Satoru; Niimura, Nobuo.

    1993-01-01

    The start of JRR-3M in 1990 was a great epoch to the neutron scattering research in Japan. Abundant neutron beam generated by the JRR-3M made it possible to widen the research field of neutron scattering in Japan. In the early days of neutron scattering, biological materials were too difficult object to be studied by neutrons not only because of their complexity but also because of the strong incoherent scattering by hydrogen. However, the remarkable development of the recent neutron scattering and its related sciences, as well as the availability of higher flux, has made the biological materials one of the most attractive subjects to be studied by neutrons. In early September 1992, an intensive workshop titled 'Neutrons in Biology' was held in Hitachi City by making use of the opportunity of the 4th International Conference on Biophysics and Synchrotron Radiation (BSR92) held in Tsukuba. The workshop was organized by volunteers who are eager to develop the researches in this field in Japan. Numbers of outstanding neutron scattering biologists from U.S., Europe and Asian countries met together and enthusiastic discussions were held all day long. The editors believe that the presentations at the workshop were so invaluable that it is absolutely adequate to put them on record as an issue of JAERI-M and to make them available for scientists to refer to in order to further promote the research in the future. (author)

  17. Physics of biological membranes

    Science.gov (United States)

    Mouritsen, Ole G.

    The biological membrane is a complex system consisting of an aqueous biomolecular planar aggregate of predominantly lipid and protein molecules. At physiological temperatures, the membrane may be considered a thin (˜50Å) slab of anisotropic fluid characterized by a high lateral mobility of the various molecular components. A substantial fraction of biological activity takes place in association with membranes. As a very lively piece of condensed matter, the biological membrane is a challenging research topic for both the experimental and theoretical physicists who are facing a number of fundamental physical problems including molecular self-organization, macromolecular structure and dynamics, inter-macromolecular interactions, structure-function relationships, transport of energy and matter, and interfacial forces. This paper will present a brief review of recent theoretical and experimental progress on such problems, with special emphasis on lipid bilayer structure and dynamics, lipid phase transitions, lipid-protein and lipid-cholesterol interactions, intermembrane forces, and the physical constraints imposed on biomembrane function and evolution. The paper advocates the dual point of view that there are a number of interesting physics problems in membranology and, at the same time, that the physical properties of biomembranes are important regulators of membrane function.

  18. Thermal and biological gasification

    Energy Technology Data Exchange (ETDEWEB)

    Overend, R.P.; Rivard, C.J. [National Renewable Energy Lab., Golden, CO (United States)

    1993-12-31

    Gasification is being developed to enable a diverse range of biomass resources to meet modern secondary energy uses, especially in the electrical utility sector. Biological or anaerobic gasification in US landfills has resulted in the installation of almost 500 MW(e) of capacity and represents the largest scale application of gasification technology today. The development of integrated gasification combined cycle generation for coal technologies is being paralleled by bagasse and wood thermal gasification systems in Hawaii and Scandinavia, and will lead to significant deployment in the next decade as the current scale-up activities are commercialized. The advantages of highly reactive biomass over coal in the design of process units are being realized as new thermal gasifiers are being scaled up to produce medium-energy-content gas for conversion to synthetic natural gas and transportation fuels and to hydrogen for use in fuel cells. The advent of high solids anaerobic digestion reactors is leading to commercialization of controlled municipal solid waste biological gasification rather than landfill application. In both thermal and biological gasification, high rate process reactors are a necessary development for economic applications that address waste and residue management and the production and use of new crops for energy. The environmental contribution of biomass in reducing greenhouse gas emission will also be improved.

  19. Biologics in spine arthrodesis.

    Science.gov (United States)

    Kannan, Abhishek; Dodwad, Shah-Nawaz M; Hsu, Wellington K

    2015-06-01

    Spine fusion is a tool used in the treatment of spine trauma, tumors, and degenerative disorders. Poor outcomes related to failure of fusion, however, have directed the interests of practitioners and scientists to spinal biologics that may impact fusion at the cellular level. These biologics are used to achieve successful arthrodesis in the treatment of symptomatic deformity or instability. Historically, autologous bone grafting, including iliac crest bong graft harvesting, had represented the gold standard in spinal arthrodesis. However, due to concerns over potential harvest site complications, supply limitations, and associated morbidity, surgeons have turned to other bone graft options known for their osteogenic, osteoinductive, and/or osteoconductive properties. Current bone graft selection includes autograft, allograft, demineralized bone matrix, ceramics, mesenchymal stem cells, and recombinant human bone morphogenetic protein. Each pose their respective advantages and disadvantages and are the focus of ongoing research investigating the safety and efficacy of their use in the setting of spinal fusion. Rh-BMP2 has been plagued by issues of widespread off-label use, controversial indications, and a wide range of adverse effects. The risks associated with high concentrations of exogenous growth factors have led to investigational efforts into nanotechnology and its application in spinal arthrodesis through the binding of endogenous growth factors. Bone graft selection remains critical to successful fusion and favorable patient outcomes, and orthopaedic surgeons must be educated on the utility and limitations of various biologics in the setting of spine arthrodesis.

  20. Biological heart valves.

    Science.gov (United States)

    Ciubotaru, Anatol; Cebotari, Serghei; Tudorache, Igor; Beckmann, Erik; Hilfiker, Andres; Haverich, Axel

    2013-10-01

    Cardiac valvular pathologies are often caused by rheumatic fever in young adults, atherosclerosis in elderly patients, or by congenital malformation of the heart in children, in effect affecting almost all population ages. Almost 300,000 heart valve operations are performed worldwide annually. Tissue valve prostheses have certain advantages over mechanical valves such as biocompatibility, more physiological hemodynamics, and no need for life-long systemic anticoagulation. However, the major disadvantage of biological valves is related to their durability. Nevertheless, during the last decade, the number of patients undergoing biological, rather than mechanical, valve replacement has increased from half to more than three-quarters for biological implants. Continuous improvement in valve fabrication includes development of new models and shapes, novel methods of tissue treatment, and preservation and implantation techniques. These efforts are focused not only on the improvement of morbidity and mortality of the patients but also on the improvement of their quality of life. Heart valve tissue engineering aims to provide durable, "autologous" valve prostheses. These valves demonstrate adaptive growth, which may avoid the need of repeated operations in growing patients.

  1. Neglect of Biological Rhythms in High School Biology Texts.

    Science.gov (United States)

    Ahlgren, Andrew; Nelson, Julie Ann

    1979-01-01

    This article developed from a survey of the five most popular biology texts which promote the theory of invariant homeostasis rather than biological rhythms. The popular fad of "birthdate biorhythms" is discussed in relation to providing education on biological rhythms and its legitimacy to the public. (SA)

  2. Is Our Biology to Blame?

    Science.gov (United States)

    Schneider, Scott

    1977-01-01

    Brief analyses of three recent examples of biological determinism: sex roles, overpopulation, and sociobiology, are presented in this article. Also a brief discussion of biological determinism and education is presented. (MR)

  3. Logical analysis of biological systems

    DEFF Research Database (Denmark)

    Mardare, Radu Iulian

    2005-01-01

    R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005.......R. Mardare, Logical analysis of biological systems. Fundamenta Informaticae, N 64:271-285, 2005....

  4. American Institute of Biological Sciences

    Science.gov (United States)

    ... Biology Classifieds Get Involved AIBS on Diversity Diversity Diversity Leadership Award Diversity Scholars Outreach Directory News Newsroom Peer ... Biology Classifieds Get Involved AIBS on Diversity Diversity Diversity Leadership Award Diversity Scholars Outreach Directory News Newsroom Contact ...

  5. Biological treatment of polluted lands

    International Nuclear Information System (INIS)

    Le Brun, S.

    2005-01-01

    Several techniques of lands cleansing exist; they include the thermal techniques, the biological treatment or the disposal. The Biogenie firm is specialized in the biological cleansing of soils on and outside site. (O.M.)

  6. Biological treatment of Crohn's disease

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Bjerrum, Jacob Tveiten; Seidelin, Jakob Benedict

    2012-01-01

    Introduction of biological agents for the treatment of Crohn's disease (CD) has led to a transformation of the treatment paradigm. Several biological compounds have been approved for patients with CD refractory to conventional treatment: infliximab, adalimumab and certolizumab pegol (and...

  7. NASA Biological Specimen Repository

    Science.gov (United States)

    McMonigal, K. A.; Pietrzyk, R. A.; Sams, C. F.; Johnson, M. A.

    2010-01-01

    The NASA Biological Specimen Repository (NBSR) was established in 2006 to collect, process, preserve and distribute spaceflight-related biological specimens from long duration ISS astronauts. This repository provides unique opportunities to study longitudinal changes in human physiology spanning may missions. The NBSR collects blood and urine samples from all participating ISS crewmembers who have provided informed consent. These biological samples are collected once before flight, during flight scheduled on flight days 15, 30, 60, 120 and within 2 weeks of landing. Postflight sessions are conducted 3 and 30 days after landing. The number of in-flight sessions is dependent on the duration of the mission. Specimens are maintained under optimal storage conditions in a manner that will maximize their integrity and viability for future research The repository operates under the authority of the NASA/JSC Committee for the Protection of Human Subjects to support scientific discovery that contributes to our fundamental knowledge in the area of human physiological changes and adaptation to a microgravity environment. The NBSR will institute guidelines for the solicitation, review and sample distribution process through establishment of the NBSR Advisory Board. The Advisory Board will be composed of representatives of all participating space agencies to evaluate each request from investigators for use of the samples. This process will be consistent with ethical principles, protection of crewmember confidentiality, prevailing laws and regulations, intellectual property policies, and consent form language. Operations supporting the NBSR are scheduled to continue until the end of U.S. presence on the ISS. Sample distribution is proposed to begin with selections on investigations beginning in 2017. The availability of the NBSR will contribute to the body of knowledge about the diverse factors of spaceflight on human physiology.

  8. Building biological foundries for next-generation synthetic biology.

    Science.gov (United States)

    Chao, Ran; Yuan, YongBo; Zhao, HuiMin

    2015-07-01

    Synthetic biology is an interdisciplinary field that takes top-down approaches to understand and engineer biological systems through design-build-test cycles. A number of advances in this relatively young field have greatly accelerated such engineering cycles. Specifically, various innovative tools were developed for in silico biosystems design, DNA de novo synthesis and assembly, construct verification, as well as metabolite analysis, which have laid a solid foundation for building biological foundries for rapid prototyping of improved or novel biosystems. This review summarizes the state-of-the-art technologies for synthetic biology and discusses the challenges to establish such biological foundries.

  9. Space Synthetic Biology Project

    Science.gov (United States)

    Howard, David; Roman, Monsi; Mansell, James (Matt)

    2015-01-01

    Synthetic biology is an effort to make genetic engineering more useful by standardizing sections of genetic code. By standardizing genetic components, biological engineering will become much more similar to traditional fields of engineering, in which well-defined components and subsystems are readily available in markets. Specifications of the behavior of those components and subsystems can be used to model a system which incorporates them. Then, the behavior of the novel system can be simulated and optimized. Finally, the components and subsystems can be purchased and assembled to create the optimized system, which most often will exhibit behavior similar to that indicated by the model. The Space Synthetic Biology project began in 2012 as a multi-Center effort. The purpose of this project was to harness Synthetic Biology principals to enable NASA's missions. A central target for application was to Environmental Control & Life Support (ECLS). Engineers from NASA Marshall Space Flight Center's (MSFC's) ECLS Systems Development Branch (ES62) were brought into the project to contribute expertise in operational ECLS systems. Project lead scientists chose to pursue the development of bioelectrochemical technologies to spacecraft life support. Therefore, the ECLS element of the project became essentially an effort to develop a bioelectrochemical ECLS subsystem. Bioelectrochemical systems exploit the ability of many microorganisms to drive their metabolisms by direct or indirect utilization of electrical potential gradients. Whereas many microorganisms are capable of deriving the energy required for the processes of interest (such as carbon dioxide (CO2) fixation) from sunlight, it is believed that subsystems utilizing electrotrophs will exhibit smaller mass, volume, and power requirements than those that derive their energy from sunlight. In the first 2 years of the project, MSFC personnel conducted modeling, simulation, and conceptual design efforts to assist the

  10. Biological targeting of radionuclides

    International Nuclear Information System (INIS)

    Wheldon, T.E.; Glasgow Univ.

    1993-01-01

    Targeted radionuclide therapy in several forms has now been investigated in the clinic for more than 10 years. Despite some promising indications, targeted radiotherapy has not yet had a large impact on cancer therapy. Theoretical analysis shows that tumour cure would not often be expected using existing treatments. Addition of external-beam irradiation appears to be a robust strategy, which is appropriate in a wide range of situations. In future, many new agents will be made available by progress in molecular biology. However, integration of targeted radionuclide therapy with other modalities, especially radiotherapy, may still be required. (Author)

  11. Programme Biology - Health protection

    International Nuclear Information System (INIS)

    1975-01-01

    The scientific results for 1975, of the five-year Biology-Health Protection programme adopted in 1971, are presented in two volumes. In volume one, Research in Radiation Protection are developed exclusively, including the following topics: measurement and interpretation of radiation (dosimetry); transfer of radioactive nuclides in the constituents of the environment; hereditary effects of radiation; short-term effects (acute irradiation syndrome and its treatment); long-term effects and toxicology of radioactive elements. In volume, two Research on applications in Agriculture and Medicine are developed. It includes: mutagenesis; soil-plant relations; radiation analysis; food conservation; cell culture; radioentomology. Research on applications in Medicine include: Nuclear Medicine and Neutron Dosimetry

  12. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  13. [The biologization of ethics].

    Science.gov (United States)

    Moreno Lax, Alejandro

    2010-01-01

    Three ethics exist as a condition of possibility of any possible ethics, following a material and biological foundation. This content argument (not logical-formal) supposes a refutation of the naturalistic fallacy that the analytical philosophy attributes to Hume, in three areas of the ethical human experience: body, society and nature. These are: the ethics of the species [J. Habermas], the ethics of liberation [E. Dussel] and the ethics of the responsibility [H. Jonas]. This material argument is a philosophical foundation to considering for three types of applied ethics: medical bioethics, development ethics and environmental ethics.

  14. Traceability of biologicals

    DEFF Research Database (Denmark)

    Vermeer, Niels S; Spierings, Irina; Mantel-Teeuwisse, Aukje K

    2015-01-01

    INTRODUCTION: Traceability is important in the postmarketing surveillance of biologicals, since changes in the manufacturing process may give rise to product- or batch-specific risks. With the expected expansion of the biosimilar market, there have been concerns about the ability to trace...... not support the routine recording of batch information. Expected changes in supply chain standards provide opportunities to systematically record detailed exposure information. Spontaneous reporting systems are the most vulnerable link in ensuring traceability, due to the manual nature of data transfer...

  15. Illuminating Cell Biology

    Science.gov (United States)

    2002-01-01

    NASA's Ames Research Center awarded Ciencia, Inc., a Small Business Innovation Research contract to develop the Cell Fluorescence Analysis System (CFAS) to address the size, mass, and power constraints of using fluorescence spectroscopy in the International Space Station's Life Science Research Facility. The system will play an important role in studying biological specimen's long-term adaptation to microgravity. Commercial applications for the technology include diverse markets such as food safety, in situ environmental monitoring, online process analysis, genomics and DNA chips, and non-invasive diagnostics. Ciencia has already sold the system to the private sector for biosensor applications.

  16. Elements in biological AMS

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, J.S.; McAninch, J.; Freeman, S.

    1996-08-01

    AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. {sup 14}C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth`s biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed.

  17. Plutonium and transplutonian biology

    International Nuclear Information System (INIS)

    Lafuma, Jacques

    1975-01-01

    The present state of knowledge in the field of plutonium and transplutonian biology is reviewed. The physico-chemical properties of these substances, the conditions in which they can contaminate human beings, their behaviour on mammals, their toxic effects and the correlative contamination treatment technique are analyzed successively. Plutonium and transplutonians, although relatively toxic, have as yet never caused severe injuries to humans. They cannot be transmitted to man through alimentary chains and constitute a hazard only for those who handle them. In this last case, the existing protection techniques offer such a high degree of efficiency that virtually all risk of contamination is eliminated [fr

  18. Biological effects of hyperthermia

    International Nuclear Information System (INIS)

    Okumura, Hiroshi

    1980-01-01

    Biological effects of hyperthermia and application of hyperthermia to cancer therapy were outlined. As to independent effects of hyperthermia, heat sensitivity of cancer cells, targets of hyperthermia, thermal tolerance of cancer cells, effects of pH on hyperthermic cell survival, effects of hyperthermia on normal tissues, and possibility of clinical application of hyperthermia were described. Combined effect of hyperthermia and x-irradiation to enhance radiosensitivity of cancer cells, its mechanism, effects of oxygen on cancer cells treated with hyperthermia and irradiation, and therapeutic ratio of combined hyperthermia and irradiation were also described. Finally, sensitizers were mentioned. (Tsunoda, M.)

  19. Mathematics and biology

    International Nuclear Information System (INIS)

    Khan, I.A.

    1991-06-01

    In India and in so many other countries, the science students are generally separated into two main streams: one opting mathematical sciences, the other studying biological sciences. As a result, medicos and biologists have no adequate knowledge of mathematical sciences. It causes a great drawback to them in order to be perfect and updated in their profession, due to the tremendous application of mathematics in bio-sciences, now-a-days. The main aim of this article is to emphasize on the need of the time to produce the mathematico-biologists in abundance for the better service of mankind. (author)

  20. Biological hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

    1995-11-01

    Biological hydrogen production can be accomplished by either thermochemical (gasification) conversion of woody biomass and agricultural residues or by microbiological processes that yield hydrogen gas from organic wastes or water. Biomass gasification is a well established technology; however, the synthesis gas produced, a mixture of CO and H{sub 2}, requires a shift reaction to convert the CO to H{sub 2}. Microbiological processes can carry out this reaction more efficiently than conventional catalysts, and may be more appropriate for the relatively small-scale of biomass gasification processes. Development of a microbial shift reaction may be a near-term practical application of microbial hydrogen production.

  1. [Frontier in bone biology].

    Science.gov (United States)

    Takeda, Shu

    2015-10-01

    Bone is an active organ in which bone mass is maintained by the balance between osteoblastic bone formation and osteoclastic bone resorption, i.e., coupling of bone formation and bone resorption. Recent advances in molecular bone biology uncovered the molecular mechanism of the coupling. A fundamental role of osteocyte in the maintenance of bone mass and whole body metabolism has also been revealed recently. Moreover, neurons and neuropeptides have been shown to be intimately involved in bone homeostasis though inter-organ network, in addition to "traditional" regulators of bone metabolism such as soluble factors and cytokines

  2. Learning Biology with Plant Pathology.

    Science.gov (United States)

    Carroll, Juliet E.

    This monograph contains 10 plant pathology experiments that were written to correspond to portions of a biology curriculum. Each experiment is suitable to a biology topic and designed to encourage exploration of those biological concepts being taught. Experiments include: (1) The Symptoms and Signs of Disease; (2) Koch's Postulates; (3)…

  3. Functions in Biological Kind Classification

    Science.gov (United States)

    Lombrozo, Tania; Rehder, Bob

    2012-01-01

    Biological traits that serve functions, such as a zebra's coloration (for camouflage) or a kangaroo's tail (for balance), seem to have a special role in conceptual representations for biological kinds. In five experiments, we investigate whether and why functional features are privileged in biological kind classification. Experiment 1…

  4. <=ryptochromes and Biological Clocks -36 ...

    Indian Academy of Sciences (India)

    production. Such repetition of biological phenomena in a peri- odic manner constitutes a 'biological rhythm'. Many biological rhythms are synchronized with solar day .... Photoactive pigment. Photosynthetic pigments of phytochrome bacteria associated with GFP. LHC = Light harvesting complex of green plants. NPH = Non ...

  5. Cameroon Journal of Experimental Biology

    African Journals Online (AJOL)

    The Cameroon Journal of Experimental Biology is the official journal of the Cameroon Forum for Biological Sciences (CAFOBIOS). It is an interdisciplinary journal for the publication of original research papers, short communications and review articles in all fields of experimental biology including biochemistry, physiology, ...

  6. Marine molecular biology: an emerging field of biological sciences.

    Science.gov (United States)

    Thakur, Narsinh L; Jain, Roopesh; Natalio, Filipe; Hamer, Bojan; Thakur, Archana N; Müller, Werner E G

    2008-01-01

    An appreciation of the potential applications of molecular biology is of growing importance in many areas of life sciences, including marine biology. During the past two decades, the development of sophisticated molecular technologies and instruments for biomedical research has resulted in significant advances in the biological sciences. However, the value of molecular techniques for addressing problems in marine biology has only recently begun to be cherished. It has been proven that the exploitation of molecular biological techniques will allow difficult research questions about marine organisms and ocean processes to be addressed. Marine molecular biology is a discipline, which strives to define and solve the problems regarding the sustainable exploration of marine life for human health and welfare, through the cooperation between scientists working in marine biology, molecular biology, microbiology and chemistry disciplines. Several success stories of the applications of molecular techniques in the field of marine biology are guiding further research in this area. In this review different molecular techniques are discussed, which have application in marine microbiology, marine invertebrate biology, marine ecology, marine natural products, material sciences, fisheries, conservation and bio-invasion etc. In summary, if marine biologists and molecular biologists continue to work towards strong partnership during the next decade and recognize intellectual and technological advantages and benefits of such partnership, an exciting new frontier of marine molecular biology will emerge in the future.

  7. The Promises of Biology and the Biology of Promises

    DEFF Research Database (Denmark)

    Lee, Jieun

    2015-01-01

    commitments with differently imagined futures. I argue that promises are constitutive of the stem cell biology, rather than being derivative of it. Since the biological concept of stem cells is predicated on the future that they promise, the biological life of stem cells is inextricably intertwined...... patients’ bodies in anticipation of materializing the promises of stem cell biology, they are produced as a new form of biovaluable. The promises of biology move beyond the closed circuit of scientific knowledge production, and proliferate in the speculative marketplaces of promises. Part II looks at how...... of technologized biology and biological time can appear promising with the backdrop of the imagined intransigence of social, political, and economic order in the Korean society....

  8. [The Biology of Learning].

    Science.gov (United States)

    Campo-Cabal, Gerardo

    2012-01-01

    The effort to relate mental and biological functioning has fluctuated between two doctrines: 1) an attempt to explain mental functioning as a collective property of the brain and 2) as one relatied to other mental processes associated with specific regions of the brain. The article reviews the main theories developed over the last 200 years: phrenology, the psuedo study of the brain, mass action, cellular connectionism and distributed processing among others. In addition, approaches have emerged in recent years that allows for an understanding of the biological determinants and individual differences in complex mental processes through what is called cognitive neuroscience. Knowing the definition of neuroscience, the learning of memory, the ways in which learning occurs, the principles of the neural basis of memory and learning and its effects on brain function, among other things, allows us the basic understanding of the processes of memory and learning and is an important requirement to address the best manner to commit to the of training future specialists in Psychiatry. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  9. Biology with neutron radiation

    International Nuclear Information System (INIS)

    Zaccai, Giuseppe

    1993-01-01

    Neutron diffraction, elastic and inelastic neutron scattering experiments provide important information on the structure, interactions and dynamics of biological molecules. This arises from the unique properties of the neutron and of its interaction with matter. Coherent and incoherent neutron scattering amplitudes and cross-sections are very different for H and 2 H (deuterium). Deuterium labelling by chemical or biochemical methods and H 2 O: 2 H 2 O exchange is the basis of high resolution crystallography experiments to locate functionally important H-atoms in protein molecules. It is also very important in low resolution crystallography and small angle scattering experiments to solve large complex structures, such as protein-nucleic acid complexes or biological membrane systems, by using contrast variation techniques. The energies of neutrons with a wavelength of the order of 1 - 10 A are similar to thermal energies and inelastic neutron scattering experiments have been done with different energy resolutions (≥∼ 1 μeV) to characterise the functional dynamics of proteins in solution and in membranes. (author)

  10. Oscillations in Mathematical Biology

    CERN Document Server

    1983-01-01

    The papers in this volume are based on talks given at a one day conference held on the campus of Adelphi University in April 1982. The conference was organized with the title "Oscillations in Mathematical Biology;" however the speakers were allowed considerable latitutde in their choice of topics. In the event, the talks all concerned the dynamics of non-linear systems arising in biology so that the conference achieved a good measure of cohesion. Some of the speakers cho~e not to submit a manuscript for these proceedings, feeling that their material was too conjectural to be committed to print. Also the paper of Rinzel and Troy is a distillation of the two separate talks that the authors gave. Otherwise the material reproduces the conference proceedings. The conference was made possible by the generous support of the Office of the Dean of the College of Arts and Sciences at Adelphi. The bulk of the organization of the conference was carried out by Dr. Ronald Grisell whose energy was in large measure responsib...

  11. Chemoradiotherapy and molecular biology

    International Nuclear Information System (INIS)

    Hasegawa, Masatoshi; Mitsuhashi, Norio; Niibe, Hideo

    2000-01-01

    The current status of chemoradiotherapy was reviewed from the standpoint of molecular biology. Chemoradiotherapy was conducted to achieve systemic tumor control, to intensify the response to irradiation, and to reduce adverse reactions. The mechanisms of the efficacy of chemoradiotherapy were: modification of dose-response relationships, inhibition of tumor cell recovery from sublethal damage or potential lethal damage, effects on cell dynamics and the cell cycle, improvement of blood flow or reoxygenation, recruitment, improvement of drug uptake, increased cell damage. Cell death (necrosis and apoptosis) and cancer-related genes were described, as the essential points, because they are involved in the response to chemoradiotherapy. Cisplatin (platinum compound), 5-fluorouracil, etoposide, and taxoid (paclitaxel, docetaxel) were the principal anticancer agents used for chemoradiotherapy, and they enhanced the effects of irradiation. However, even when good responses or synergism between anticancer drug and radiotherapy was observed in in vitro studies, there was little therapeutic advantage clinically. Data from in vitro and in vivo studies should be collected and systemized, and ''molecular biology in chemotherapy'' that can be applied clinically may become established. (K.H.)

  12. Microgravity Fluids for Biology, Workshop

    Science.gov (United States)

    Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.

    2013-01-01

    Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

  13. Mathematical modeling of biological processes

    CERN Document Server

    Friedman, Avner

    2014-01-01

    This book on mathematical modeling of biological processes includes a wide selection of biological topics that demonstrate the power of mathematics and computational codes in setting up biological processes with a rigorous and predictive framework. Topics include: enzyme dynamics, spread of disease, harvesting bacteria, competition among live species, neuronal oscillations, transport of neurofilaments in axon, cancer and cancer therapy, and granulomas. Complete with a description of the biological background and biological question that requires the use of mathematics, this book is developed for graduate students and advanced undergraduate students with only basic knowledge of ordinary differential equations and partial differential equations; background in biology is not required. Students will gain knowledge on how to program with MATLAB without previous programming experience and how to use codes in order to test biological hypothesis.

  14. Human biology of taste.

    Science.gov (United States)

    Gravina, Stephen A; Yep, Gregory L; Khan, Mehmood

    2013-01-01

    Taste or gustation is one of the 5 traditional senses including hearing, sight, touch, and smell. The sense of taste has classically been limited to the 5 basic taste qualities: sweet, salty, sour, bitter, and umami or savory. Advances from the Human Genome Project and others have allowed the identification and determination of many of the genes and molecular mechanisms involved in taste biology. The ubiquitous G protein-coupled receptors (GPCRs) make up the sweet, umami, and bitter receptors. Although less clear in humans, transient receptor potential ion channels are thought to mediate salty and sour taste; however, other targets have been identified. Furthermore, taste receptors have been located throughout the body and appear to be involved in many regulatory processes. An emerging interplay is revealed between chemical sensing in the periphery, cortical processing, performance, and physiology and likely the pathophysiology of diseases such as diabetes.

  15. Neutron structural biology

    Energy Technology Data Exchange (ETDEWEB)

    Niimura, Nobuo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    Neutron diffraction provides an experimental method of directly locating hydrogen atoms in protein which play important roles in physiological functions. However, there are relatively few examples of neutron crystallography in biology since it takes a lot of time to collect a sufficient number of Bragg reflections due to the low flux of neutrons illuminating the sample. In order to overcome the flux problem, we have successfully developed the neutron IP, where the neutron converter, {sup 6}Li or Gd, was mixed with a photostimulated luminescence material on flexible plastic support. Neutron Laue diffraction 2A data from tetragonal lysozyme were collected for 10 days with neutron imaging plates, and 960 hydrogen atoms in the molecule and 157 bound water molecules were identified. These results explain the proposed hydrolysis mechanism of the sugar by the lysozyme molecule and that lysozyme is less active at pH7.0. (author)

  16. Hormesis and plant biology

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, Edward J. [Department of Public Health, Environmental Health Sciences Division, Pleasant Street, Morrill I, N344, University of Massachusetts, Amherst, MA 01003 (United States)], E-mail: edwardc@schoolph.umass.edu; Blain, Robyn B. [Department of Public Health, Environmental Health Sciences Division, Pleasant Street, Morrill I, N344, University of Massachusetts, Amherst, MA 01003 (United States)

    2009-01-15

    A database has been developed that demonstrates experimental evidence of hormesis. It includes information from a broad range of biological models, including plants, and information on study design, dose-response features, and physical/chemical properties of the agents. An assessment of plant hormetic dose responses is presented based on greater than 3000 plant endpoints. Plant hormetic dose responses were observed for numerous endpoints including disease incidence, reproductive indices, mutagenic endpoints, various metabolic parameters, developmental processes, and a range of growth indicators. Quantitative features of these dose responses typically display a maximum stimulatory response less than two-fold greater than controls and a width of the stimulatory response usually less than 10-fold in dose range. The database establishes that hormetic dose responses commonly occur in plants, are broadly generalizable, and have quantitative features similar to hormetic dose responses found for animals. - Hormesis commonly occurs within plant species.

  17. National Biological Monitoring Inventory

    International Nuclear Information System (INIS)

    Burgess, R.L.

    1979-01-01

    The National Biological Monitoring Inventory, initiated in 1975, currently consists of four computerized data bases and voluminous manual files. MAIN BIOMON contains detailed information on 1,021 projects, while MINI BIOMON provides skeletal data for over 3,000 projects in the 50 states, Puerto Rico, the Virgin Islands, plus a few in Canada and Mexico. BIBLIO BIOMON and DIRECTORY BIOMON complete the computerized data bases. The structure of the system provides for on-line search capabilities to generate details of agency sponsorship, indications of funding levels, taxonomic and geographic coverage, length of program life, managerial focus or emphasis, and condition of the data. Examples of each of these are discussed and illustrated, and potential use of the Inventory in a variety of situations is emphasized

  18. The biology of strigolactones

    KAUST Repository

    Ruyter-Spira, Carolien P.

    2013-02-01

    The strigolactones are rhizosphere signaling molecules as well as a new class of plant hormones with a still increasing number of biological functions being uncovered. Here, we review a recent major breakthrough in our understanding of strigolactone biosynthesis, which has revealed the unexpected simplicity of the originally postulated complex pathway. Moreover, the discovery and localization of a strigolactone exporter sheds new light on putative strigolactone fluxes to the rhizosphere as well as within the plant. The combination of these data with information on the expression and regulation of strigolactone biosynthetic and downstream signaling genes provides new insights into how strigolactones control the many different aspects of plant development and how their rhizosphere signaling role may have evolved. © 2012 Elsevier Ltd.

  19. Plant Vascular Biology 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Biao

    2014-11-17

    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes. The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.

  20. Networks in Cell Biology

    Science.gov (United States)

    Buchanan, Mark; Caldarelli, Guido; De Los Rios, Paolo; Rao, Francesco; Vendruscolo, Michele

    2010-05-01

    Introduction; 1. Network views of the cell Paolo De Los Rios and Michele Vendruscolo; 2. Transcriptional regulatory networks Sarath Chandra Janga and M. Madan Babu; 3. Transcription factors and gene regulatory networks Matteo Brilli, Elissa Calistri and Pietro Lió; 4. Experimental methods for protein interaction identification Peter Uetz, Björn Titz, Seesandra V. Rajagopala and Gerard Cagney; 5. Modeling protein interaction networks Francesco Rao; 6. Dynamics and evolution of metabolic networks Daniel Segré; 7. Hierarchical modularity in biological networks: the case of metabolic networks Erzsébet Ravasz Regan; 8. Signalling networks Gian Paolo Rossini; Appendix 1. Complex networks: from local to global properties D. Garlaschelli and G. Caldarelli; Appendix 2. Modelling the local structure of networks D. Garlaschelli and G. Caldarelli; Appendix 3. Higher-order topological properties S. Ahnert, T. Fink and G. Caldarelli; Appendix 4. Elementary mathematical concepts A. Gabrielli and G. Caldarelli; References.

  1. Biological aspects of chemoradiotherapy

    International Nuclear Information System (INIS)

    Bourhis, J.; Mornex, F.

    1998-01-01

    Radio-chemotherapy combinations, especially their concomitant associations, are widely used in the treatment of cancer. The development of these associations has been so far related more to clinical research than to laboratory experiments. The biological basis of the use of these agents relies on their complementarity which concerns the cellular and molecular mechanisms involved in lethality (hypoxia, sensitivity throughout the cycle, DNA repair, apoptosis), spatial and temporal cooperation, etc. Laboratory experiments can determine favorable conditions for additivity, or supra-additivity, but also for infra-additive interactions as well as real antagonism which should be avoided in the clinic. It is however often difficult to transfer this information into the clinic since the conditions which allow additivity or supra-additivity are generally very narrow, and unlikely to be realised in the patient. General clinical conditions are more compatible with infra-additive interactions. (author)

  2. Biological effects of neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Ogiu, Toshiaki; Ohmachi, Yasushi; Ishida, Yuka [National Inst. of Radiological Sciences, Chiba (JP)] [and others

    2003-03-01

    Although the occasion to be exposed to neutrons is rare in our life, except for nuclear accidents like in the critical accident at Tokai-mura in 1999, countermeasures against accident should be always prepared. In the Tokai-mura accident, residents received less than 21 mSv of neutrons and gamma rays. The cancer risks and fetal effects of low doses of neutrons were matters of concern among residents. The purpose of this program is to investigate the relative biological effectiveness (RBE) for leukemias, and thereby to assess risks of neutrons. Animal experiments are planed to obtain the following RBEs: (1) RBE for the induction of leukemias in mice and (2) RBE for effects on fetuses. Cyclotron fast neutrons (10 MeV) and electrostatic accelerator-derived neutrons (2 MeV) are used for exposure in this program. Furthermore, cytological and cytogenetic analyses will be performed. (author)

  3. Biologic poisons for pain.

    Science.gov (United States)

    Reisner, Lori

    2004-12-01

    Pain therapies from natural sources date back thousands of years to the use of plant and animal extracts for a variety of painful conditions and injuries. We certainly are all familiar with modern uses of plant-derived analgesic compounds such as opium derivatives from papaverum somniferum and salicylates from willow bark (Salix species). Local anesthetics were isolated from coca leaves in the late 1800s. Sarapin, derived from carnivorous pitcher plants, has been injected for regional analgesia in human and veterinary medicine, but efficacy is controversial. Biologic organisms can play important roles in developing an understanding of pain mechanisms, either from isolation of compounds that are analgesic or of compounds that produce pain, hyperalgesia, and allodynia.

  4. Evolution of Biological Complexity

    Science.gov (United States)

    Goldstein, Raymond E.

    It is a general rule of nature that larger organisms are more complex, at least as measured by the number of distinct types of cells present. This reflects the fitness advantage conferred by a division of labor among specialized cells over homogeneous totipotency. Yet, increasing size has both costs and benefits, and the search for understanding the driving forces behind the evolution of multicellularity is becoming a very active area of research. This article presents an overview of recent experimental and theoretical work aimed at understanding this biological problem from the perspective of physics. For a class of model organisms, the Volvocine green algae, an emerging hypothesis connects the transition from organisms with totipotent cells to those with terminal germ-soma differentiation to the competition between diffusion and fluid advection created by beating flagella. A number of challenging problems in fluid dynamics, nonlinear dynamics, and control theory emerge when one probes the workings of the simplest multicellular organisms.

  5. Biology of Schwann cells.

    Science.gov (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate. Copyright © 2013 Elsevier B.V. All rights

  6. Nanoelectronics Meets Biology

    Science.gov (United States)

    Lieber, Charles

    2012-02-01

    Nanoscale materials enable unique opportunities at the interface between the physical and life sciences, and the interface between nanoelectronic devices and biological systems makes possible communication between these two diverse systems at the length scale relevant to biological function. In this presentation, the development of nanowire nanoelectronic devices and their application as powerful tools for the life sciences will be discussed. First, a brief introduction to nanowire nanoelectronic devices as well as comparisons to other electrophysiological tools will be presented to illuminate the unique strengths and opportunities enabled at the nanoscale. Second, illustration of detection capabilities including signal-to-noise and applications for real-time label-free detection of biochemical markers down to the level of single molecules will be described. Third, the use of nanowire nanoelectronics for building interfaces to cells and tissue will be reviewed. Multiplexed measurements made from nanowire devices fabricated on flexible and transparent substrates recording signal propagation across cultured cells, acute tissue slices and intact organs will be illustrated, including quantitative analysis of the high simultaneous spatial and temporal resolution achieved with these nanodevices. Specific examples of subcellular and near point detection of extracellular potential will be used to illustrate the unique capabilities, such as recording localized potential changes due to neuronal activities simultaneously across many length scales, which provide key information for functional neural circuit studies. Last, emerging opportunities for the creation of powerful new probes based on controlled synthesis and/or bottom-up assembly of nanomaterials will be described with an emphasis on nanowire probes demonstrating the first intracellular transistor recordings, and the development of ``cyborg'' tissue. The prospects for blurring the distinction between nanoelectronic

  7. Integrative Radiation Biology

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [New York University School of Medicine, NY (United States)

    2015-02-27

    We plan to study tissue-level mechanisms important to human breast radiation carcinogenesis. We propose that the cell biology of irradiated tissues reveals a coordinated multicellular damage response program in which individual cell contributions are primarily directed towards suppression of carcinogenesis and reestablishment of homeostasis. We identified transforming growth factor β1 (TGFβ) as a pivotal signal. Notably, we have discovered that TGFβ suppresses genomic instability by controlling the intrinsic DNA damage response and centrosome integrity. However, TGFβ also mediates disruption of microenvironment interactions, which drive epithelial to mesenchymal transition in irradiated human mammary epithelial cells. This apparent paradox of positive and negative controls by TGFβ is the topic of the present proposal. First, we postulate that these phenotypes manifest differentially following fractionated or chronic exposures; second, that the interactions of multiple cell types in tissues modify the responses evident in this single cell type culture models. The goals are to: 1) study the effect of low dose rate and fractionated radiation exposure in combination with TGFβ on the irradiated phenotype and genomic instability of non-malignant human epithelial cells; and 2) determine whether stromal-epithelial interactions suppress the irradiated phenotype in cell culture and the humanized mammary mouse model. These data will be used to 3) develop a systems biology model that integrates radiation effects across multiple levels of tissue organization and time. Modeling multicellular radiation responses coordinated via extracellular signaling could have a significant impact on the extrapolation of human health risks from high dose to low dose/rate radiation exposure.

  8. The Physics behind Systems Biology

    Directory of Open Access Journals (Sweden)

    Radde Nicole E.

    2016-12-01

    Full Text Available Systems Biology is a young and rapidly evolving research field, which combines experimental techniques and mathematical modeling in order to achieve a mechanistic understanding of processes underlying the regulation and evolution of living systems. Systems Biology is often associated with an Engineering approach: The purpose is to formulate a data-rich, detailed simulation model that allows to perform numerical (‘in silico’ experiments and then draw conclusions about the biological system. While methods from Engineering may be an appropriate approach to extending the scope of biological investigations to experimentally inaccessible realms and to supporting data-rich experimental work, it may not be the best strategy in a search for design principles of biological systems and the fundamental laws underlying Biology. Physics has a long tradition of characterizing and understanding emergent collective behaviors in systems of interacting units and searching for universal laws. Therefore, it is natural that many concepts used in Systems Biology have their roots in Physics. With an emphasis on Theoretical Physics, we will here review the ‘Physics core’ of Systems Biology, show how some success stories in Systems Biology can be traced back to concepts developed in Physics, and discuss how Systems Biology can further benefit from its Theoretical Physics foundation.

  9. Synthetic biology and occupational risk.

    Science.gov (United States)

    Howard, John; Murashov, Vladimir; Schulte, Paul

    2017-03-01

    Synthetic biology is an emerging interdisciplinary field of biotechnology that involves applying the principles of engineering and chemical design to biological systems. Biosafety professionals have done an excellent job in addressing research laboratory safety as synthetic biology and gene editing have emerged from the larger field of biotechnology. Despite these efforts, risks posed by synthetic biology are of increasing concern as research procedures scale up to industrial processes in the larger bioeconomy. A greater number and variety of workers will be exposed to commercial synthetic biology risks in the future, including risks to a variety of workers from the use of lentiviral vectors as gene transfer devices. There is a need to review and enhance current protection measures in the field of synthetic biology, whether in experimental laboratories where new advances are being researched, in health care settings where treatments using viral vectors as gene delivery systems are increasingly being used, or in the industrial bioeconomy. Enhanced worker protection measures should include increased injury and illness surveillance of the synthetic biology workforce; proactive risk assessment and management of synthetic biology products; research on the relative effectiveness of extrinsic and intrinsic biocontainment methods; specific safety guidance for synthetic biology industrial processes; determination of appropriate medical mitigation measures for lentiviral vector exposure incidents; and greater awareness and involvement in synthetic biology safety by the general occupational safety and health community as well as by government occupational safety and health research and regulatory agencies.

  10. Quantum Mechanics predicts evolutionary biology.

    Science.gov (United States)

    Torday, J S

    2018-01-11

    Nowhere are the shortcomings of conventional descriptive biology more evident than in the literature on Quantum Biology. In the on-going effort to apply Quantum Mechanics to evolutionary biology, merging Quantum Mechanics with the fundamentals of evolution as the First Principles of Physiology-namely negentropy, chemiosmosis and homeostasis-offers an authentic opportunity to understand how and why physics constitutes the basic principles of biology. Negentropy and chemiosmosis confer determinism on the unicell, whereas homeostasis constitutes Free Will because it offers a probabilistic range of physiologic set points. Similarly, on this basis several principles of Quantum Mechanics also apply directly to biology. The Pauli Exclusion Principle is both deterministic and probabilistic, whereas non-localization and the Heisenberg Uncertainty Principle are both probabilistic, providing the long-sought after ontologic and causal continuum from physics to biology and evolution as the holistic integration recognized as consciousness for the first time. Copyright © 2018. Published by Elsevier Ltd.

  11. Quantum Effects in Biological Systems

    CERN Document Server

    2016-01-01

    Since the last decade the study of quantum mechanical phenomena in biological systems has become a vibrant field of research. Initially sparked by evidence of quantum effects in energy transport that is instrumental for photosynthesis, quantum biology asks the question of how methods and models from quantum theory can help us to understand fundamental mechanisms in living organisms. This approach entails a paradigm change challenging the related disciplines: The successful framework of quantum theory is taken out of its low-temperature, microscopic regimes and applied to hot and dense macroscopic environments, thereby extending the toolbox of biology and biochemistry at the same time. The Quantum Effects in Biological Systems conference is a platform for researchers from biology, chemistry and physics to present and discuss the latest developments in the field of quantum biology. After meetings in Lisbon (2009), Harvard (2010), Ulm (2011), Berkeley (2012), Vienna (2013), Singapore (2014) and Florence (2015),...

  12. Microfluidic Technologies for Synthetic Biology

    Directory of Open Access Journals (Sweden)

    Sung Kuk Lee

    2011-06-01

    Full Text Available Microfluidic technologies have shown powerful abilities for reducing cost, time, and labor, and at the same time, for increasing accuracy, throughput, and performance in the analysis of biological and biochemical samples compared with the conventional, macroscale instruments. Synthetic biology is an emerging field of biology and has drawn much attraction due to its potential to create novel, functional biological parts and systems for special purposes. Since it is believed that the development of synthetic biology can be accelerated through the use of microfluidic technology, in this review work we focus our discussion on the latest microfluidic technologies that can provide unprecedented means in synthetic biology for dynamic profiling of gene expression/regulation with high resolution, highly sensitive on-chip and off-chip detection of metabolites, and whole-cell analysis.

  13. INNOVATION IN ACCOUNTING BIOLOGIC ASSETS

    OpenAIRE

    Stolуarova M. A.; Shcherbina I. D.

    2016-01-01

    The article describes the innovations in the classification and measurement of biological assets according to IFRS (IAS) 41 "Agriculture". The difficulties faced by agricultural producers using standard, set out in article. The classification based on the adopted amendments, according to which the fruit-bearing plants, previously accounted for as biological assets are measured at fair value are included in the category of fixed assets. The structure of biological assets and main means has bee...

  14. Biology of ionizing radiation effects

    International Nuclear Information System (INIS)

    Ferradini, C.; Pucheault, J.

    1983-01-01

    The present trends in biology of ionizing radiation are reviewed. The following topics are investigated: interaction of ionizing radiations with matter; the radiolysis of water and aqueous solutions; properties of the free radicals intervening in the couples O 2 /H 2 O and H 2 O/H 2 ; radiation chemistry of biological compounds; biological effects of ionizing radiations; biochemical mechanisms involving free radicals as intermediates; applications (biotechnological applications, origins of life) [fr

  15. Systems Biology and Health Systems Complexity in;

    NARCIS (Netherlands)

    Donald Combs, C.; Barham, S.R.; Sloot, P.M.A.

    2016-01-01

    Systems biology addresses interactions in biological systems at different scales of biological organization, from the molecular to the cellular, organ, organism, societal, and ecosystem levels. This chapter expands on the concept of systems biology, explores its implications for individual patients

  16. Biological and medical sensor technologies

    CERN Document Server

    Iniewski, Krzysztof

    2012-01-01

    Biological and Medical Sensor Technologies presents contributions from top experts who explore the development and implementation of sensors for various applications used in medicine and biology. Edited by a pioneer in the area of advanced semiconductor materials, the book is divided into two sections. The first part covers sensors for biological applications. Topics include: Advanced sensing and communication in the biological world DNA-derivative architectures for long-wavelength bio-sensing Label-free silicon photonics Quartz crystal microbalance-based biosensors Lab-on-chip technologies fo

  17. Electromagnetic fields in biological systems

    National Research Council Canada - National Science Library

    Lin, James C

    2012-01-01

    "Focusing on exposure, induced fields, and absorbed energy, this volume covers the interaction of electromagnetic fields and waves with biological systems, spanning static fields to terahertz waves...

  18. Telemetry System of Biological Parameters

    Directory of Open Access Journals (Sweden)

    Jan Spisak

    2005-01-01

    Full Text Available The mobile telemetry system of biological parameters serves for reading and wireless data transfer of measured values of selected biological parameters to an outlying computer. It concerns basically long time monitoring of vital function of car pilot.The goal of this projects is to propose mobile telemetry system for reading, wireless transfer and processing of biological parameters of car pilot during physical and psychical stress. It has to be made with respect to minimal consumption, weight and maximal device mobility. This system has to eliminate signal noise, which is created by biological artifacts and disturbances during the data transfer.

  19. Regulatory Biology: Depressed Metabolic States

    Science.gov (United States)

    Holton, E. M. (Editor)

    1973-01-01

    Exobiological aspects of depressed metabolism and thermoregulation are discussed for subsequent development of biological space flight experiments. Included is a brief description of differential hypothermia in cancer chemotherapy.

  20. The biology of marine plants

    National Research Council Canada - National Science Library

    Dring, M.J

    1982-01-01

    .... Phytoplankton and seaweeds are discussed together in chapters on photosynthesis, growth and productivity, and geographical distribution, in order to provide an integrated picture of the biology...

  1. Excited states in biological systems

    International Nuclear Information System (INIS)

    Cilento, G.; Zinner, K.; Bechara, E.J.H.; Duran, N.; Baptista, R.C. de; Shimizu, Y.; Augusto, O.; Faljoni-Alario, A.; Vidigal, C.C.C.; Oliveira, O.M.M.F.; Haun, M.

    1979-01-01

    Some aspects of bioluminescence related to bioenergetics are discussed: 1. chemical generation of excited species, by means of two general processes: electron transference and cyclic - and linear peroxide cleavage; 2. biological systems capable of generating excited states and 3. biological functions of these states, specially the non-emissive ones (tripletes). The production and the role of non-emissive excited states in biological systems are analysed, the main purpose of the study being the search for non-emissive states. Experiences carried out in biological systems are described; results and conclusions are given. (M.A.) [pt

  2. Synthetic biology for therapeutic applications.

    Science.gov (United States)

    Abil, Zhanar; Xiong, Xiong; Zhao, Huimin

    2015-02-02

    Synthetic biology is a relatively new field with the key aim of designing and constructing biological systems with novel functionalities. Today, synthetic biology devices are making their first steps in contributing new solutions to a number of biomedical challenges, such as emerging bacterial antibiotic resistance and cancer therapy. This review discusses some synthetic biology approaches and applications that were recently used in disease mechanism investigation and disease modeling, drug discovery and production, as well as vaccine development and treatment of infectious diseases, cancer, and metabolic disorders.

  3. Finding Hope in Synthetic Biology.

    Science.gov (United States)

    Takala, Tuija

    2017-04-01

    For some, synthetic biology represents great hope in offering possible solutions to many of the world's biggest problems, from hunger to sustainable development. Others remain fearful of the harmful uses, such as bioweapons, that synthetic biology can lend itself to, and most hold that issues of biosafety are of utmost importance. In this article, I will evaluate these points of view and conclude that although the biggest promises of synthetic biology are unlikely to become reality, and the probability of accidents is fairly substantial, synthetic biology could still be seen to benefit humanity by enhancing our ethical understanding and by offering a boost to world economy.

  4. [Biology molecular of glioblastomas].

    Science.gov (United States)

    Franco-Hernández, C; Martínez-Glez, V; Rey, J A

    2007-10-01

    Glioblastomas, the most frequent and malignant human brain tumors, may develop de novo (primary glioblastoma) or by progression from low-grade or anapalsic astrocytoma (secondary glioblastoma). The molecular alteration most frequent in these tumor-like types is the loss of heterozygosity on chromosome 10, in which several genes have been identified as tumors suppressor. The TP53/MDM2/P14arf and CDK4/RB1/ P16ink4 genetic pathways involved in cycle control are deregulated in the majority of gliomas as well as genes that promote the cellular division, EGFR. Finally the increase of growth and angiogenics factors is also involved in the development of glioblastomas. One of the objectives of molecular biology in tumors of glial ancestry is to try to find the genetic alterations that allow to approach better the classification of glioblastomas, its evolution prediction and treatment. The new pathmolecular classification of gliomas should improve the old one, especially being concerned about the oncogenesis and heterogeneity of these tumors. It is desirable that this classification had clinical applicability and integrates new molecular findings with some known histological features with pronostic value. In this paper we review the most frequent molecular mechanisms involved in the patogenesis of glioblastomas.

  5. Mesangial cell biology

    International Nuclear Information System (INIS)

    Abboud, Hanna E.

    2012-01-01

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  6. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail: Abboud@uthscsa.edu

    2012-05-15

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  7. Eosinophils in glioblastoma biology

    Directory of Open Access Journals (Sweden)

    Curran Colleen S

    2012-01-01

    Full Text Available Abstract Glioblastoma multiforme (GBM is the most common primary brain tumor in adults. The development of this malignant glial lesion involves a multi-faceted process that results in a loss of genetic or epigenetic gene control, un-regulated cell growth, and immune tolerance. Of interest, atopic diseases are characterized by a lack of immune tolerance and are inversely associated with glioma risk. One cell type that is an established effector cell in the pathobiology of atopic disease is the eosinophil. In response to various stimuli, the eosinophil is able to produce cytotoxic granules, neuromediators, and pro-inflammatory cytokines as well as pro-fibrotic and angiogenic factors involved in pathogen clearance and tissue remodeling and repair. These various biological properties reveal that the eosinophil is a key immunoregulatory cell capable of influencing the activity of both innate and adaptive immune responses. Of central importance to this report is the observation that eosinophil migration to the brain occurs in response to traumatic brain injury and following certain immunotherapeutic treatments for GBM. Although eosinophils have been identified in various central nervous system pathologies, and are known to operate in wound/repair and tumorstatic models, the potential roles of eosinophils in GBM development and the tumor immunological response are only beginning to be recognized and are therefore the subject of the present review.

  8. Mammalian cell biology

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Progress is reported on studies of the molecular biology and functional changes in cultured mammalian cells following exposure to x radiation, uv radiation, fission neutrons, or various chemical environmental pollutants alone or in combinations. Emphasis was placed on the separate and combined effects of polycyclic aromatic hydrocarbons released during combustion of fossil fuels and ionizing and nonionizing radiations. Sun lamps, which emit a continuous spectrum of near ultraviolet light of 290 nm to 315 nm were used for studies of predictive cell killing due to sunlight. Results showed that exposure to uv light (254 nm) may not be adequate to predict effects produced by sunlight. Data are included from studies on single-strand breaks and repair in DNA of cultured hamster cells exposed to uv or nearultraviolet light. The possible interactions of the polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)-anthracene (DmBA) alone or combined with exposure to x radiation, uv radiation (254 nm) or near ultraviolet simulating sunlight were compared for effects on cell survival

  9. Flotation of Biological Materials

    Directory of Open Access Journals (Sweden)

    George Z. Kyzas

    2014-03-01

    Full Text Available Flotation constitutes a gravity separation process, which originated from the minerals processing field. However, it has, nowadays, found several other applications, as for example in the wastewater treatment field. Concerning the necessary bubble generation method, typically dispersed-air or dissolved-air flotation was mainly used. Various types of biological materials were tested and floated efficiently, such as bacteria, fungi, yeasts, activated sludge, grape stalks, etc. Innovative processes have been studied in our Laboratory, particularly for metal ions removal, involving the initial abstraction of heavy metal ions onto a sorbent (including a biosorbent: in the first, the application of a flotation stage followed for the efficient downstream separation of metal-laden particles. The ability of microorganisms to remove metal ions from dilute aqueous solutions (as most wastewaters are is a well-known property. The second separation process, also applied effectively, was a new hybrid cell of microfiltration combined with flotation. Sustainability in this field and its significance for the chemical and process industry is commented.

  10. Bomb pulse biology

    Energy Technology Data Exchange (ETDEWEB)

    Falso, Miranda J. Sarachine [Center for Accelerator Mass Spectrometry, Mail Stop L-397, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States); Buchholz, Bruce A., E-mail: buchholz2@llnl.gov [Center for Accelerator Mass Spectrometry, Mail Stop L-397, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551 (United States)

    2013-01-15

    The past decade has seen an explosion in use of the {sup 14}C bomb pulse to do fundamental cell biology. Studies in the 1960s used decay counting to measure tissue turnover when the atmospheric {sup 14}C/C concentration was changing rapidly. Today bulk tissue measurements are of marginal interest since most of the carbon in the tissue resides in proteins, lipids and carbohydrates that turn over rapidly. Specific cell types with specialized functions are the focus of cell turnover investigations. Tissue samples need to be fresh or frozen. Fixed or preserved samples contain petroleum-derived carbon that has not been successfully removed. Cell or nuclear surface markers are used to sort specific cell types, typically by fluorescence-activated cell sorting (FACS). Specific biomolecules need to be isolated with high purity and accelerator mass spectrometry (AMS) measurements must accommodate samples that generally contain less than 40 {mu}g of carbon. Furthermore, all separations must not add carbon to the sample. Independent means such as UV absorbance must be used to confirm molecule purity. Approaches for separating specific proteins and DNA and combating contamination of undesired molecules are described.

  11. Pathogenesis and biology.

    Science.gov (United States)

    Winkler, Frank

    2018-01-01

    Metastasis to the brain is an increasing complication of solid cancers. Fortunately, our understanding of its pathogenesis has greatly increased in the last decade, with crucial insights into the molecular and cellular determinants of successful brain colonization; some aspects remain less well understood. The latter include the exact features of brain metastasis-initiating cancer cells, and a potential premetastatic niche. It is clear that a brain-arrested cancer cell has to master a sequence of steps to eventually grow to a clinically relevant brain metastasis. Various brain-specific cell types and molecular niches promote or hinder brain colonization in a dynamic and reciprocal manner. After mandatory extravasation and colonization of a brain-specific perivascular niche, the cancer cell can stay dormant, or further grow by dynamic interactions with cerebral blood vessels. In addition, the activation of certain molecular pathways on site of the cancer cell which are related to growth, motility, survival, and adaptation to the brain environment appears also important, given their characteristic modification in brain metastases of patients. A deeper understanding of the most vulnerable steps of the brain metastatic cascade may foster the development of novel preventive approaches, and that of core biologic mechanisms for macrometastatic growth and persistence will help to develop better therapeutics. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Molecular biology of potyviruses.

    Science.gov (United States)

    Revers, Frédéric; García, Juan Antonio

    2015-01-01

    Potyvirus is the largest genus of plant viruses causing significant losses in a wide range of crops. Potyviruses are aphid transmitted in a nonpersistent manner and some of them are also seed transmitted. As important pathogens, potyviruses are much more studied than other plant viruses belonging to other genera and their study covers many aspects of plant virology, such as functional characterization of viral proteins, molecular interaction with hosts and vectors, structure, taxonomy, evolution, epidemiology, and diagnosis. Biotechnological applications of potyviruses are also being explored. During this last decade, substantial advances have been made in the understanding of the molecular biology of these viruses and the functions of their various proteins. After a general presentation on the family Potyviridae and the potyviral proteins, we present an update of the knowledge on potyvirus multiplication, movement, and transmission and on potyvirus/plant compatible interactions including pathogenicity and symptom determinants. We end the review providing information on biotechnological applications of potyviruses. © 2015 Elsevier Inc. All rights reserved.

  13. Exploring Visuomotor Priming Following Biological and Non-Biological Stimuli

    Science.gov (United States)

    Gowen, E.; Bradshaw, C.; Galpin, A.; Lawrence, A.; Poliakoff, E.

    2010-01-01

    Observation of human actions influences the observer's own motor system, termed visuomotor priming, and is believed to be caused by automatic activation of mirror neurons. Evidence suggests that priming effects are larger for biological (human) as opposed to non-biological (object) stimuli and enhanced when viewing stimuli in mirror compared to…

  14. "Protected biological control"- Biological pest management in the greenhouse industry

    NARCIS (Netherlands)

    Pilkington, L.J.; Messelink, G.J.; Lenteren, van J.C.; Mottee, Le K.

    2010-01-01

    This paper briefly describes the foundations and characteristics of biological control in protected cropping and what drivers are behind adoption of this management system within this industry. Examining a brief history of biological control in greenhouses and what makes it a successful management

  15. Ecology, Ecosystem Management and Biology Teaching. Biology and Human Welfare.

    Science.gov (United States)

    Spellerberg, Ian F.; Pritchard, Alan J.

    This six-chapter document (part of a series on biology and human welfare) focuses on ecology, ecosystem management, and biology teaching. Chapter 1 discusses the basic elements of ecology (considering organisms and their environment, populations, and communities and ecosystems). Chapter 2 describes several aspects of human ecology and resources…

  16. Relations between intuitive biological thinking and biological misconceptions in biology majors and nonmajors.

    Science.gov (United States)

    Coley, John D; Tanner, Kimberly

    2015-03-02

    Research and theory development in cognitive psychology and science education research remain largely isolated. Biology education researchers have documented persistent scientifically inaccurate ideas, often termed misconceptions, among biology students across biological domains. In parallel, cognitive and developmental psychologists have described intuitive conceptual systems--teleological, essentialist, and anthropocentric thinking--that humans use to reason about biology. We hypothesize that seemingly unrelated biological misconceptions may have common origins in these intuitive ways of knowing, termed cognitive construals. We presented 137 undergraduate biology majors and nonmajors with six biological misconceptions. They indicated their agreement with each statement, and explained their rationale for their response. Results indicate frequent agreement with misconceptions, and frequent use of construal-based reasoning among both biology majors and nonmajors in their written explanations. Moreover, results also show associations between specific construals and the misconceptions hypothesized to arise from those construals. Strikingly, such associations were stronger among biology majors than nonmajors. These results demonstrate important linkages between intuitive ways of thinking and misconceptions in discipline-based reasoning, and raise questions about the origins, persistence, and generality of relations between intuitive reasoning and biological misconceptions. © 2015 J. D. Coley and K. Tanner. CBE—Life Sciences Education © 2015 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  17. Medical-biological problems

    International Nuclear Information System (INIS)

    1986-01-01

    The report contains data on operational and emergency staff of the Chernobyl nuclear power plant who were exposed to radiation as a consequence of the reactor accident, the size of the doses received and consequences for health. 203 persons were found to have acute radiation sickness. Of the 22 patients suffering from an extremely severe degree of acute radiation sickness, 19 died. Of the 23 patients with severe bone marrow syndrome, 7 died. For the majority of patients, clinical recovery occurred toward the end of the second month following the accident. The main harmful factor for all victims was the relatively uniform gamma- and beta-radiation effect in a dosage exceeding 1 Gy and, in the case of 35 people exceeding 4 Gy. Radiation damage to wide areas of the skin was one of the main factors contributing to the overall severe condition of the patients, and was a determining factor in the main fatal complications. A preliminary evaluation of the use of some biochemical and immunological tests in the event of accidental exposure to radiation and the methods of treatment and preliminary assessment of their effectiveness are presented. Another part of the report contains data on the doses from radiation exposure to the population of the town of Pripyat' until the time of evacuation and to the population in the 30 km zone around Chernobyl' nuclear power plant and radiation consequences of the accident for the population of different regions in the European part of the USSR, especially the problems related to the contamination of food products. The last part of the report gives some data on the organization of medical examinations of the population from the region around the Chernobyl' plant and on the long-term programmes for the medical and biological monitoring of the population and personnel

  18. Biological radiation effects

    International Nuclear Information System (INIS)

    Sejourne, Michele.

    1977-01-01

    This work examines ionizing radiations: what they are, where they come from, their actions and consequences, finally the norms and preventive measures necessary to avoid serious contamination, whether the individual or the population in general is involved. Man has always been exposed to natural irradiation, but owing to the growing use of ionizing radiations both in medicine and in industry, not to mention nuclear tests and their use as an argument of dissuasion, the irradiation of human beings is increasing daily. Radioactive contamination does remain latent, apart from acute cases, but this is where the danger lies since the consequences may not appear until long after the irradiation. Of all biological effects due to the action of radioelements the genetic risk is one of the most important, affecting the entire population and especially the generations to come. The risk of cancer and leukemia induction plays a substantial part also since a large number of people may be concerned, depending on the mode of contamination involved. All these long-term dangers do not of course exclude the various general or local effects to which the individual alone may be exposed and which sometimes constitute a threat to life. As a result the use of ionizing radiations must be limited and should only be involved if no other process can serve instead. The regulations governing radioelements must be stringent and their application strictly supervised for the better protection of man. This protection must be not only individual but also collective since pollution exists in air, water and land passes to plants and animals and finally reaches the last link in the food chain, man [fr

  19. Egyptian Journal of Biology: Submissions

    African Journals Online (AJOL)

    Author Guidelines. Address for manuscripts via email: samyzalat@hotmail.com via post: Professor Samy Zalat, Egyptian-British Biological Society, Department of Zoology, Suez Canal University, Ismailia, Egypt. Instructions for authors. Manuscripts for the Egyptian Journal of Biology should normally not exceed 15 typed ...

  20. Computational aspects of systematic biology.

    Science.gov (United States)

    Lilburn, Timothy G; Harrison, Scott H; Cole, James R; Garrity, George M

    2006-06-01

    We review the resources available to systematic biologists who wish to use computers to build classifications. Algorithm development is in an early stage, and only a few examples of integrated applications for systematic biology are available. The availability of data is crucial if systematic biology is to enter the computer age.

  1. Marine Biology and Human Affairs

    Science.gov (United States)

    Russell, F. S.

    1976-01-01

    Marine biology has become an important area for study throughout the world. The author of this article discusses some of the important discoveries and fields of research in marine biology that are useful for mankind. Topics include food from the sea, fish farming, pesticides, pollution, and conservation. (MA)

  2. An Integrated Approach to Biology

    Indian Academy of Sciences (India)

    An Integrated Approach to Biology. Aniket Bhattacharya. Keywords. Zoology, genomics, schistoso- miasis, schistosome genomics, praziquantel, origin of clothing. Zoology, being a basic bioscience, is essential for a better understanding of applied biological disciplines. A sound back- ground in zoology can often be the key ...

  3. Biological Implications of Artificial Illumination.

    Science.gov (United States)

    Wurtman, Richard J.

    1968-01-01

    Environmental lighting exerts profound biologic effects on humans and other mammals, in addition to providing the visual stimulus. Light acts on the skin to stimulate the synthesis of Vitamin D. It also acts, through the eyes, to control several glands and many metabolic processes. Light, or its absence, "induces" certain biologic functions. Light…

  4. Do-it-yourself biology

    NARCIS (Netherlands)

    Golinelli, Stefano; Ruivenkamp, Guido

    2016-01-01

    Do-it-yourself biology, or garage biology, is a set of practices through which lay people can practice biotechnology and thus also challenge the exclusive control exercised on biotech R&D by Big Bio. This article describes how garage biologists aim to radically transform biotechnological

  5. Brassinosteroids: synthesis and biological activities

    Czech Academy of Sciences Publication Activity Database

    Oklešťková, Jana; Rárová, Lucie; Kvasnica, Miroslav; Strnad, Miroslav

    2015-01-01

    Roč. 14, č. 6 (2015), s. 1053-1072 ISSN 1568-7767 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Brassinosteroids * Chemical synthesis * Plant biological activity Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.686, year: 2015

  6. Biology and Water Pollution Control.

    Science.gov (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  7. Archives: Egyptian Journal of Biology

    African Journals Online (AJOL)

    Items 1 - 17 of 17 ... Archives: Egyptian Journal of Biology. Journal Home > Archives: Egyptian Journal of Biology. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 17 of 17 Items ...

  8. Systems Biology and Livestock Science

    NARCIS (Netherlands)

    Pas, te M.F.W.; Woelders, H.; Bannink, A.

    2011-01-01

    Systems Biology is an interdisciplinary approach to the study of life made possible through the explosion of molecular data made available through the genome revolution and the simultaneous development of computational technologies that allow us to interpret these large data sets. Systems Biology

  9. Structural Biology Guides Antibiotic Discovery

    Science.gov (United States)

    Polyak, Steven

    2014-01-01

    Modern drug discovery programs require the contribution of researchers in a number of specialist areas. One of these areas is structural biology. Using X-ray crystallography, the molecular basis of how a drug binds to its biological target and exerts its mode of action can be defined. For example, a drug that binds into the active site of an…

  10. Towards Logical Designs In Biology

    Indian Academy of Sciences (India)

    Towards Logical Designs in Biology. Garima Agarwal. General Article Volume 12 Issue 2 February 2007 pp 29-38. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/012/02/0029-0038. Keywords. Synthetic biology; logic gates; regulatory modules; gene circuits. Author Affiliations.

  11. Biological clocks: riding the tides.

    Science.gov (United States)

    de la Iglesia, Horacio O; Johnson, Carl Hirschie

    2013-10-21

    Animals with habitats in the intertidal zone often display biological rhythms that coordinate with both the tidal and the daily environmental cycles. Two recent studies show that the molecular components of the biological clocks mediating tidal rhythms are likely different from the phylogenetically conserved components that mediate circadian (daily) rhythms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Static Analysis for Systems Biology

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis; Rosa, D. Schuch da

    2004-01-01

    This paper shows how static analysis techniques can help understanding biological systems. Based on a simple example we illustrate the outcome of performing three different analyses extracting information of increasing precision. We conclude by reporting on the potential impact and exploitation o...... of these techniques in systems biology....

  13. Querying Large Biological Network Datasets

    Science.gov (United States)

    Gulsoy, Gunhan

    2013-01-01

    New experimental methods has resulted in increasing amount of genetic interaction data to be generated every day. Biological networks are used to store genetic interaction data gathered. Increasing amount of data available requires fast large scale analysis methods. Therefore, we address the problem of querying large biological network datasets.…

  14. Biological monitoring of radiation exposure

    Science.gov (United States)

    Horneck, G.

    1998-11-01

    Complementary to physical dosimetry, biological dosimetry systems have been developed and applied which weight the different components of environmental radiation according to their biological efficacy. They generally give a record of the accumulated exposure of individuals with high sensitivity and specificity for the toxic agent under consideration. Basically three different types of biological detecting/monitoring systems are available: (i) intrinsic biological dosimeters that record the individual radiation exposure (humans, plants, animals) in measurable units. For monitoring ionizing radiation exposure, in situ biomarkers for genetic (e.g. chromosomal aberrations in human lymphocytes, germ line minisatellite mutation rates) or metabolic changes in serum, plasma and blood (e.g. serum lipids, lipoproteins, lipid peroxides, melatonin, antibody titer) have been used. (ii) Extrinsic biological dosimeters/indicators that record the accumulated dose in biological model systems. Their application includes long-term monitoring of changes in environmental UV radiation and its biological implications as well as dosimetry of personal UV exposure. (iii) Biological detectors/biosensors for genotoxic substances and agents such as bacterial assays (e.g. Ames test, SOS-type test) that are highly sensitive to genotoxins with high specificity. They may be applicable for different aspects in environmental monitoring including the International Space Station.

  15. Synthetic biology of polyketide synthases

    DEFF Research Database (Denmark)

    Yuzawa, Satoshi; Backman, Tyler W.H.; Keasling, Jay D.

    2018-01-01

    ). The modules are composed of enzymatic domains that share sequence and functional similarity across all known PKSs. We have used the nomenclature of synthetic biology to classify the enzymatic domains and modules as parts and devices, respectively, and have generated detailed lists of both. In addition, we...... realize the potential that synthetic biology approaches bring to this class of molecules....

  16. From Biology to Quality (BQ)

    DEFF Research Database (Denmark)

    Nielsen, Michael Engelbrecht; Ingerslev, Hans-Christian

    2011-01-01

    “Quality is never an accident; it is always the result of high intention, sincere effort, intelligent direction and skilful execution; it represents the wise choice of many alternatives.” (William A. Foster) The quality of fish meat is dependent upon a wide range of biological and non-biological ...

  17. Validation of systems biology models

    NARCIS (Netherlands)

    Hasdemir, D.

    2015-01-01

    The paradigm shift from qualitative to quantitative analysis of biological systems brought a substantial number of modeling approaches to the stage of molecular biology research. These include but certainly are not limited to nonlinear kinetic models, static network models and models obtained by the

  18. Biological Effectiveness of Antiproton Annihilation

    DEFF Research Database (Denmark)

    Maggiore, C.; Agazaryan, N.; Bassler, N.

    2004-01-01

    from the annihilation of antiprotons produce an increase in ‘‘biological dose’’ in the vicinity of the narrow Bragg peak for antiprotons compared to protons. This experiment is the first direct measurement of the biological effects of antiproton annihilation. The background, description, and status...

  19. Biological novelty in the anthropocene.

    Science.gov (United States)

    Fuentes, Marcelino

    2018-01-21

    It is well known that humans are creating new variants of organisms, ecosystems and landscapes. Here I argue that the degree of biological novelty generated by humans goes deeper than that. We use property rules to create exclusivity in cooperation among humans, and between humans and other biological entities, thus overcoming social dilemmas and breaking barriers to cooperation. This is leading to novel forms of cooperation. One of them is the human control, modification and replication of whole ecosystems. For the first time, there exist ecosystems with functional design, division of labor and unlimited heredity. We use mental representation and language as new mechanisms of inheritance and modification that apply to an increasing variety of biological and non-biological entities. As a result, the speed, depth and scale of biological innovation are unprecedented in the history of life. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Redesigning Introductory Biology: A Proposal

    Directory of Open Access Journals (Sweden)

    Eileen Gregory

    2011-03-01

    Full Text Available With the increasing complexity and expansion of the biological sciences, there has been a corresponding increase in content in the first-year introductory biology course sequence for majors. In general this has resulted in courses that introduce students to large amounts of material and leave little time for practicing investigative science or skill development. Based on our analysis of data compiled from 742 biology faculty at a variety of institutions across the United States, we verified that there is strong agreement on the content appropriate for introductory biology courses for majors. Therefore, we propose that faculty teaching these courses focus primarily on the topics identified in this study, and redesign their courses to incorporate active learning strategies that emphasize the investigative nature of biology and provide opportunities for skill development.

  1. Electromagnetic fields in biological systems

    CERN Document Server

    Lin, James C

    2016-01-01

    As wireless technology becomes more sophisticated and accessible to more users, the interactions of electromagnetic fields with biological systems have captured the interest not only of the scientific community but also the general public. Unintended or deleterious biological effects of electromagnetic fields and radiation may indicate grounds for health and safety precautions in their use. Spanning static fields to terahertz waves, Electromagnetic Fields in Biological Systems explores the range of consequences these fields have on the human body. With contributions by an array of experts, topics discussed include: Essential interactions and field coupling phenomena, highlighting their importance in research on biological effects and in scientific, industrial, and medical applications Electric field interactions in cells, focusing on ultrashort, pulsed high-intensity fields The effect of exposure to naturally occurring and human-made static, low-frequency, and pulsed magnetic fields in biological systems Dosi...

  2. Synthetic biology: engineering molecular computers

    CERN Document Server

    CERN. Geneva

    2018-01-01

    Complicated systems cannot survive the rigors of a chaotic environment, without balancing mechanisms that sense, decide upon and counteract the exerted disturbances. Especially so with living organisms, forced by competition to incredible complexities, escalating also their self-controlling plight. Therefore, they compute. Can we harness biological mechanisms to create artificial computing systems? Biology offers several levels of design abstraction: molecular machines, cells, organisms... ranging from the more easily-defined to the more inherently complex. At the bottom of this stack we find the nucleic acids, RNA and DNA, with their digital structure and relatively precise interactions. They are central enablers of designing artificial biological systems, in the confluence of engineering and biology, that we call Synthetic biology. In the first part, let us follow their trail towards an overview of building computing machines with molecules -- and in the second part, take the case study of iGEM Greece 201...

  3. Quantum biology of the retina.

    Science.gov (United States)

    Sia, Paul Ikgan; Luiten, André N; Stace, Thomas M; Wood, John Pm; Casson, Robert J

    2014-08-01

    The emerging field of quantum biology has led to a greater understanding of biological processes at the microscopic level. There is recent evidence to suggest that non-trivial quantum features such as entanglement, tunnelling and coherence have evolved in living systems. These quantum features are particularly evident in supersensitive light-harvesting systems such as in photosynthesis and photoreceptors. A biomimetic strategy utilizing biological quantum phenomena might allow new advances in the field of quantum engineering, particularly in quantum information systems. In addition, a better understanding of quantum biological features may lead to novel medical diagnostic and therapeutic developments. In the present review, we discuss the role of quantum physics in biological systems with an emphasis on the retina. © 2014 Royal Australian and New Zealand College of Ophthalmologists.

  4. Organisational closure in biological organisms.

    Science.gov (United States)

    Mossio, Matteo; Moreno, Alvaro

    2010-01-01

    The central aim of this paper consists in arguing that biological organisms realize a specific kind of causal regime that we call "organisational closure"; i.e., a distinct level of causation, operating in addition to physical laws, generated by the action of material structures acting as constraints. We argue that organisational closure constitutes a fundamental property of biological systems since even its minimal instances are likely to possess at least some of the typical features of biological organisation as exhibited by more complex organisms. Yet, while being a necessary condition for biological organization, organisational closure underdetermines, as such, the whole set of requirements that a system has to satisfy in order to be taken as a paradigmatic example of organism. As we suggest, additional properties, as modular templates and control mechanisms via dynamical decoupling between constraints, are required to get the complexity typical of full-fledged biological organisms.

  5. Combining supramolecular chemistry with biology.

    Science.gov (United States)

    Uhlenheuer, Dana A; Petkau, Katja; Brunsveld, Luc

    2010-08-01

    Supramolecular chemistry has primarily found its inspiration in biological molecules, such as proteins and lipids, and their interactions. Currently the supramolecular assembly of designed compounds can be controlled to great extent. This provides the opportunity to combine these synthetic supramolecular elements with biomolecules for the study of biological phenomena. This tutorial review focuses on the possibilities of the marriage of synthetic supramolecular architectures and biological systems. It highlights that synthetic supramolecular elements are for example ideal platforms for the recognition and modulation of proteins and cells. The unique features of synthetic supramolecular systems with control over size, shape, valency, and interaction strength allow the generation of structures fitting the demands to approach the biological problems at hand. Supramolecular chemistry has come full circle, studying the biology and its molecules which initially inspired its conception.

  6. Biology and Economics: Metaphors that Economists usually take from Biology

    Directory of Open Access Journals (Sweden)

    Danny García Callejas

    2007-10-01

    Full Text Available Adam Smith, Alfred Marshall, Stanley Jevons, Karl Marx, Francois Quesnay and Joseph Schumpeter all have at least one thing in common: they used biological metaphors when speaking about economics. Nonetheless, today, this relation subsists and biology and economics are viewed as complementary sciences that have a lot to gain from joint research in fields like: evolutionary economics, economic growth, cognitive economics and environmental and ecological economics, among others. This paper, divided in four sections, will show this conclusion and explain that biology and economics are more sisters than strangers

  7. Molecular biology and reproduction.

    Science.gov (United States)

    McDonough, P G

    1999-03-01

    Modern molecular biology has provided unique insights into the fundamental understanding of reproductive disorders and the detection of microorganisms. The remarkable advances in DNA diagnostics have been expedited by the development of polymerase chain reaction (PCR) and the ability to isolate DNA and RNA from many different sources such as blood, saliva, hair roots, microscopic slides, paraffin-embedded tissue sections, clinical swabs, and even cancellous bone. These technical advances have been bolstered by the development of an increasing number of effective screening techniques to scan genomic DNA for unknown point mutations. The continued development of technology will ultimately result in automated DNA (desoxyribonucleic acid) diagnosis for the practicing clinician. The continuing expansion of information concerning the human genome will place an increasing emphasis on bioinformatics and the use of computer software for analyzing DNA sequences. With the automation of DNA diagnosis and the use of small samples (500 nanograms), the direct examination of the DNA of a patient, fetus, or microorganism will emerge as a definitive means of establishing the presence of the specific genetic change that causes disease. A knowledge of the precise pathology at the molecular level has and will provide important insights into the biochemical basis for many human diseases. A firm knowledge of the DNA alterations in disease and expression patterns of specific genes will provide for more directed therapeutic strategies. The refinement of vector technology and nuclear transplantion techniques will provide the opportunity for directed gene therapy to the early human embryo. This presentation is designed to acquaint the reader with current techniques of testing at the DNA level, prototype mutations in the reproductive sciences, new concepts in the molecular mechanisms of disease that affect reproduction, and therapeutic opportunities for the future. It is hoped that future

  8. Biological modulation of tectonics

    Science.gov (United States)

    Sleep, N. H.; Bird, D. K.

    2008-12-01

    Photosynthesis has had geologic consequences over the Earth's history. In addition to modifying Earth's atmosphere and ocean chemistry, it has also modulated tectonic processes through enhanced weathering and modification of the nature and composition of sedimentary rocks within fold mountain belts and convergent margins. Molecular biological studies indicate that bacterial photosynthesis evolved just once and that most bacterial clades descend from this photosynthetic common ancestor. Iron-based photosynthesis (ideally 4FeO + CO2 + H2O = 2Fe2O3 + CH2O) was the most bountiful anoxygenic niche on land. The back reaction provided energy to heterotrophic microbes and returned FeO to the photosynthetic microbes. Bacterial land colonists evolved into ecosystems that effectively weathered FeO-bearing minerals and volcanic glass. Clays, sands, and dissolved cations from the weathering process entered the ocean and formed our familiar classes sedimentary rocks: shales, sandstones, and carbonates. Marine photosynthesis caused organic carbon to accumulate in black shales. In contrast, non-photosynthetic ecosystems do not cause organic carbon to accumulate in shale. These evolutionary events occurred before 3.8 Ga as black shales are among the oldest rock types (Rosing and Frei, Earth Planet. Sci. Lett. 217, 237-244, 2004). Thick sedimentary sequences deformed into fold mountain belts. They remelted at depth to form granitic rocks (Rosing et al., Palaeoclimatol. Palaeoecol. 232, 99-11, 2006). Regions of outcropping low-FeO rocks including granites, quartzites, and some shales were a direct result. This dearth of FeO favored the evolution of oxic photosynthesis of cyanobacteria from photosynthetic soil bacteria. Black shales have an additional modulation effect on tectonics as they concentrate radioactive elements, particularly uranium (e.g. so that the surface heat flow varies by a factor of ca. 2). Thick sequences of black shales at continental rises of passive margins are

  9. Synthetic biology and metabolic engineering.

    Science.gov (United States)

    Stephanopoulos, Gregory

    2012-11-16

    Metabolic engineering emerged 20 years ago as the discipline occupied with the directed modification of metabolic pathways for the microbial synthesis of various products. As such, it deals with the engineering (design, construction, and optimization) of native as well as non-natural routes of product synthesis, aided in this task by the availability of synthetic DNA, the core enabling technology of synthetic biology. The two fields, however, only partially overlap in their interest in pathway engineering. While fabrication of biobricks, synthetic cells, genetic circuits, and nonlinear cell dynamics, along with pathway engineering, have occupied researchers in the field of synthetic biology, the sum total of these areas does not constitute a coherent definition of synthetic biology with a distinct intellectual foundation and well-defined areas of application. This paper reviews the origins of the two fields and advances two distinct paradigms for each of them: that of unit operations for metabolic engineering and electronic circuits for synthetic biology. In this context, metabolic engineering is about engineering cell factories for the biological manufacturing of chemical and pharmaceutical products, whereas the main focus of synthetic biology is fundamental biological research facilitated by the use of synthetic DNA and genetic circuits.

  10. Digital 'faces' of synthetic biology.

    Science.gov (United States)

    Friedrich, Kathrin

    2013-06-01

    In silicio design plays a fundamental role in the endeavour to synthesise biological systems. In particular, computer-aided design software enables users to manage the complexity of biological entities that is connected to their construction and reconfiguration. The software's graphical user interface bridges the gap between the machine-readable data on the algorithmic subface of the computer and its human-amenable surface represented by standardised diagrammatic elements. Notations like the Systems Biology Graphical Notation (SBGN), together with interactive operations such as drag & drop, allow the user to visually design and simulate synthetic systems as 'bio-algorithmic signs'. Finally, the digital programming process should be extended to the wet lab to manufacture the designed synthetic biological systems. By exploring the different 'faces' of synthetic biology, I argue that in particular computer-aided design (CAD) is pushing the idea to automatically produce de novo objects. Multifaceted software processes serve mutually aesthetic, epistemic and performative purposes by simultaneously black-boxing and bridging different data sources, experimental operations and community-wide standards. So far, synthetic biology is mainly a product of digital media technologies that structurally mimic the epistemological challenge to take both qualitative as well as quantitative aspects of biological systems into account in order to understand and produce new and functional entities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Fostering synergy between cell biology and systems biology.

    Science.gov (United States)

    Eddy, James A; Funk, Cory C; Price, Nathan D

    2015-08-01

    In the shared pursuit of elucidating detailed mechanisms of cell function, systems biology presents a natural complement to ongoing efforts in cell biology. Systems biology aims to characterize biological systems through integrated and quantitative modeling of cellular information. The process of model building and analysis provides value through synthesizing and cataloging information about cells and molecules, predicting mechanisms and identifying generalizable themes, generating hypotheses and guiding experimental design, and highlighting knowledge gaps and refining understanding. In turn, incorporating domain expertise and experimental data is crucial for building towards whole cell models. An iterative cycle of interaction between cell and systems biologists advances the goals of both fields and establishes a framework for mechanistic understanding of the genome-to-phenome relationship. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  12. Agroterrorism, Biological Crimes, and Biological Warfare Targeting Animal Agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Terry M.; Logan-Henfrey, Linda; Weller, Richard E.; Kellman, Brian

    2000-04-12

    There is a rising level of concern that agriculture might be targeted for economic sabotage by terrorists. Knowledge gathered about the Soviet Union biological weapons program and Iraq following the Gulf War, confirmed that animals and agricultural crops were targets of bioweapon development. These revelations are particularly disturbing in light of the fact that both countries are States Parties to the Biological and Toxin Weapons Convention that entered into force in 1975. The potential for misusing biotechnology to create more virulent pathogens and the lack of international means to detect unethical uses of new technologies to create destructive bioweapons is of increasing concern. Disease outbreaks, whether naturally occurring or intentionally, involving agricultural pathogens that destroy livestock and crops would have a profound impact on a country's infrastructure, economy and export markets. This chapter deals with the history of agroterrorism, biological crimes and biological warfare directed toward animal agriculture, specifically, horses, cattle, swine, sheep, goats, and poultry.

  13. The Relationships between Epistemic Beliefs in Biology and Approaches to Learning Biology among Biology-Major University Students in Taiwan

    Science.gov (United States)

    Lin, Yi-Chun; Liang, Jyh-Chong; Tsai, Chin-Chung

    2012-01-01

    The aim of this study was to investigate the relationships between students' epistemic beliefs in biology and their approaches to learning biology. To this end, two instruments, the epistemic beliefs in biology and the approaches to learning biology surveys, were developed and administered to 520 university biology students, respectively. By and…

  14. Mesoscopic models of biological membranes

    DEFF Research Database (Denmark)

    Venturoli, M.; Sperotto, Maria Maddalena; Kranenburg, M.

    2006-01-01

    Phospholipids are the main components of biological membranes and dissolved in water these molecules self-assemble into closed structures, of which bilayers are the most relevant from a biological point of view. Lipid bilayers are often used, both in experimental and by theoretical investigations...... to coarse grain a biological membrane. The conclusion of this comparison is that there can be many valid different strategies, but that the results obtained by the various mesoscopic models are surprisingly consistent. A second objective of this review is to illustrate how mesoscopic models can be used...

  15. Chemical reporters for biological discovery.

    Science.gov (United States)

    Grammel, Markus; Hang, Howard C

    2013-08-01

    Functional tools are needed to understand complex biological systems. Here we review how chemical reporters in conjunction with bioorthogonal labeling methods can be used to image and retrieve nucleic acids, proteins, glycans, lipids and other metabolites in vitro, in cells as well as in whole organisms. By tagging these biomolecules, researchers can now monitor their dynamics in living systems and discover specific substrates of cellular pathways. These advances in chemical biology are thus providing important tools to characterize biological pathways and are poised to facilitate our understanding of human diseases.

  16. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R

    2014-01-01

    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  17. The renaissance of developmental biology.

    Science.gov (United States)

    St Johnston, Daniel

    2015-05-01

    Since its heyday in the 1980s and 90s, the field of developmental biology has gone into decline; in part because it has been eclipsed by the rise of genomics and stem cell biology, and in part because it has seemed less pertinent in an era with so much focus on translational impact. In this essay, I argue that recent progress in genome-wide analyses and stem cell research, coupled with technological advances in imaging and genome editing, have created the conditions for the renaissance of a new wave of developmental biology with greater translational relevance.

  18. The Ethics of Synthetic Biology

    DEFF Research Database (Denmark)

    Christiansen, Andreas

    The dissertation analyses and discusses a number of ethical issues that have been raised in connection with the development of synthetic biology. Synthetic biology is a set of new techniques for DNA-level design and construction of living beings with useful properties. The dissertation especially......) popular responsesto them succeed, and whether the objections are ultimately persuasive.2. Given that synthetic biology is a new technology, there is a certain degree of uncertainty about its ultimate effects, and many perceive the technology as risky. I discuss two common approaches in risk regulation...

  19. Ten questions about systems biology

    DEFF Research Database (Denmark)

    Joyner, Michael J; Pedersen, Bente K

    2011-01-01

    In this paper we raise 'ten questions' broadly related to 'omics', the term systems biology, and why the new biology has failed to deliver major therapeutic advances for many common diseases, especially diabetes and cardiovascular disease. We argue that a fundamentally narrow and reductionist...... to understand how whole animals adapt to the real world. We argue that a lack of fluency in these concepts is a major stumbling block for what has been narrowly defined as 'systems biology' by some of its leading advocates. We also point out that it is a failure of regulation at multiple levels that causes many...

  20. Biological Methods and Manual Development

    Science.gov (United States)

    EPA scientists conduct research to develop and evaluate analytical methods for the identification, enumeration, evaluation of aquatic organisms exposed to environmental stressors and to correlate exposures with effects on chemical and biological indicators

  1. Biological anti-TNF drugs

    DEFF Research Database (Denmark)

    Prado, Mônica Simon; Bendtzen, Klaus; Andrade, Luis Eduardo Coelho

    2017-01-01

    is frequently caused by antibodies against immune-biologicals, known as anti-drug antibodies (ADA). ADA that neutralize circulating immune-biologicals and/or promote their clearance can reduce treatment efficacy. Furthermore, ADA can induce adverse events by diverse immunological mechanisms. This review...... provides a comprehensive overview of ADA in rheumatoid arthritis patients treated with anti-TNF immune-biologicals, and explores the concept of therapeutic drug monitoring (TDM) as an effective strategy to improve therapeutic management. Expert opinion: Monitoring circulating ADA and therapeutic immune......-biological drugs is helpful when evaluating patients with secondary failure. However, immunological tests for ADA vary considerably regarding their ability to detect different types of ADA. Several assays are not designed to determine ADA-induced drug neutralizing capacity, and they may report clinically non...

  2. Biological Sample Monitoring Database (BSMDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Biological Sample Monitoring Database System (BSMDBS) was developed for the Northeast Fisheries Regional Office and Science Center (NER/NEFSC) to record and...

  3. Inference problems in structural biology

    DEFF Research Database (Denmark)

    Olsson, Simon

    The structure and dynamics of biological molecules are essential for their function. Consequently, a wealth of experimental techniques have been developed to study these features. However, while experiments yield detailed information about geometrical features of molecules, this information...

  4. Systems biology of human atherosclerosis.

    Science.gov (United States)

    Shalhoub, Joseph; Sikkel, Markus B; Davies, Kerry J; Vorkas, Panagiotis A; Want, Elizabeth J; Davies, Alun H

    2014-01-01

    Systems biology describes a holistic and integrative approach to understand physiology and pathology. The "omic" disciplines include genomics, transcriptomics, proteomics, and metabolic profiling (metabonomics and metabolomics). By adopting a stance, which is opposing (yet complimentary) to conventional research techniques, systems biology offers an overview by assessing the "net" biological effect imposed by a disease or nondisease state. There are a number of different organizational levels to be understood, from DNA to protein, metabolites, cells, organs and organisms, even beyond this to an organism's context. Systems biology relies on the existence of "nodes" and "edges." Nodes are the constituent part of the system being studied (eg, proteins in the proteome), while the edges are the way these constituents interact. In future, it will be increasingly important to collaborate, collating data from multiple studies to improve data sets, making them freely available and undertaking integrative analyses.

  5. Molecular biology of the cell

    National Research Council Canada - National Science Library

    Alberts, Bruce; Walter, Peter; Raff, Martin; Roberts, Keith; Lewis, Julian; Johnson, Alexander

    2007-01-01

    .... By extracting fundamental concepts and meaning from this enormous and ever-growing field, the authors tell the story of cell biology, and create a coherent framework through which non-expert readers...

  6. Molecular biomimetics: nanotechnology through biology

    Science.gov (United States)

    Sarikaya, Mehmet; Tamerler, Candan; Jen, Alex K.-Y.; Schulten, Klaus; Baneyx, François

    2003-09-01

    Proteins, through their unique and specific interactions with other macromolecules and inorganics, control structures and functions of all biological hard and soft tissues in organisms. Molecular biomimetics is an emerging field in which hybrid technologies are developed by using the tools of molecular biology and nanotechnology. Taking lessons from biology, polypeptides can now be genetically engineered to specifically bind to selected inorganic compounds for applications in nano- and biotechnology. This review discusses combinatorial biological protocols, that is, bacterial cell surface and phage-display technologies, in the selection of short sequences that have affinity to (noble) metals, semiconducting oxides and other technological compounds. These genetically engineered proteins for inorganics (GEPIs) can be used in the assembly of functional nanostructures. Based on the three fundamental principles of molecular recognition, self-assembly and DNA manipulation, we highlight successful uses of GEPI in nanotechnology.

  7. VT Biodiversity Project - Biological Hotspots

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This dataset is the result of an effort to map biological "hotspots" in Vermont based on the "element occurrences" in the Nongame and Natural...

  8. Yeast genetics and molecular biology

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    This book covers subjects and the following titles: cell biology; RNA processing and translation; organelle biogenesis; cell division cycle; mating physiology; recombination and repair; retro-transposition; and metabolic regulating mechanisms

  9. Synthetic Biology for Specialty Chemicals.

    Science.gov (United States)

    Markham, Kelly A; Alper, Hal S

    2015-01-01

    In this review, we address recent advances in the field of synthetic biology and describe how those tools have been applied to produce a wide variety of chemicals in microorganisms. Here we classify the expansion of the synthetic biology toolbox into three different categories based on their primary function in strain engineering-for design, for construction, and for optimization. Next, focusing on recent years, we look at how chemicals have been produced using these new synthetic biology tools. Advances in producing fuels are briefly described, followed by a more thorough treatment of commodity chemicals, specialty chemicals, pharmaceuticals, and nutraceuticals. Throughout this review, an emphasis is placed on how synthetic biology tools are applied to strain engineering. Finally, we discuss organism and host strain diversity and provide a future outlook in the field.

  10. Tumor Biology and Microenvironment Research

    Science.gov (United States)

    Part of NCI's Division of Cancer Biology's research portfolio, research in this area seeks to understand the role of tumor cells and the tumor microenvironment (TME) in driving cancer initiation, progression, maintenance and recurrence.

  11. The relativity of biological function.

    Science.gov (United States)

    Laubichler, Manfred D; Stadler, Peter F; Prohaska, Sonja J; Nowick, Katja

    2015-12-01

    Function is a central concept in biological theories and explanations. Yet discussions about function are often based on a narrow understanding of biological systems and processes, such as idealized molecular systems or simple evolutionary, i.e., selective, dynamics. Conflicting conceptions of function continue to be used in the scientific literature to support certain claims, for instance about the fraction of "functional DNA" in the human genome. Here we argue that all biologically meaningful interpretations of function are necessarily context dependent. This implies that they derive their meaning as well as their range of applicability only within a specific theoretical and measurement context. We use this framework to shed light on the current debate about functional DNA and argue that without considering explicitly the theoretical and measurement contexts all attempts to integrate biological theories are prone to fail.

  12. Inference problems in structural biology

    DEFF Research Database (Denmark)

    Olsson, Simon

    The structure and dynamics of biological molecules are essential for their function. Consequently, a wealth of experimental techniques have been developed to study these features. However, while experiments yield detailed information about geometrical features of molecules, this information is of...

  13. New vistas for developmental biology

    Indian Academy of Sciences (India)

    Author Affiliations. Scott F Gilbert1 Rocky S Tuan2. Department of Biology, Swarthmore College, 500 College Avenue, Swarthmore, PA 19081, USA; Department of Orthopaedic Surgery, Thomas Jefferson University, 1015 Walnut Street, Philadelphia, PA 19107, USA ...

  14. Text mining for systems biology.

    Science.gov (United States)

    Fluck, Juliane; Hofmann-Apitius, Martin

    2014-02-01

    Scientific communication in biomedicine is, by and large, still text based. Text mining technologies for the automated extraction of useful biomedical information from unstructured text that can be directly used for systems biology modelling have been substantially improved over the past few years. In this review, we underline the importance of named entity recognition and relationship extraction as fundamental approaches that are relevant to systems biology. Furthermore, we emphasize the role of publicly organized scientific benchmarking challenges that reflect the current status of text-mining technology and are important in moving the entire field forward. Given further interdisciplinary development of systems biology-orientated ontologies and training corpora, we expect a steadily increasing impact of text-mining technology on systems biology in the future. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Biological control of toxic cyanobacteria

    CSIR Research Space (South Africa)

    Ndlela, L

    2016-04-01

    Full Text Available harmful algal blooms and their impacts in over 30 countries. Biological control is a method of introducing natural enemies to control an organism and has been more successful using microorganisms....

  16. Biological Markers and Salivary Cortisol

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Gunnarsson, Lars-Gunnar; Harris, Anette

    2011-01-01

    This chapter focuses on salivary cortisol in relation to biological markers. Specifically, associations with conventional cardiovascular risk factors and metabolic abnormalities (body mass index, waist circumference, waist/hip ratio, lipid status, glucose, blood pressure, heart rate and heart rate...

  17. [Important issues of biological safety].

    Science.gov (United States)

    Onishchenko, G G

    2007-01-01

    The problem of biological security raises alarm due to the real growth of biological threats. Biological security includes a wide scope of problems, the solution of which becomes a part of national security as a necessary condition for the constant development of the country. A number of pathogens, such as human immunodeficiency virus, exotic Ebola and Lassa viruses causing hemorrhagic fever,rotaviruses causing acute intestinal diseases, etc. were first discovered in the last century. Terrorist actions committed in the USA in 2001 using the anthrax pathogen made the problem of biological danger even more important. In Russian Federation, biological threats are counteracted through the united state policy being a part of general state security policy. The biological Security legislation of Russian Federation is chiefly based on the 1992 Federal Law on Security. On the basis of cumulated experience, the President of Russia ratified Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond on 4 December, 2003. The document determines the main directions and stages of the state development in the area of chemical and biological security. The Federal target program Russian Federation's National Program for Chemical and Biological Security is being developed, and its development is to be completed soon in order to perfect the national system for biological security and fulfill Basics of Russian Federation's State Policy for Chemical and Biological Security for the Period through 2010 and Beyond, ratified by the President. The new global strategy for control over infectious diseases, presented in the materials of Saint Petersburg summit of the Group of Eight, as well as the substantive part of its elements in Sanitary International Standards, are to a large degree an acknowledgement of the Russian Federation's experience and the algorithm for fighting extremely dangerous infections. This Russia's experience has

  18. Biological Activities of Hydrazone Derivatives

    Directory of Open Access Journals (Sweden)

    S. Güniz Küçükgüzel

    2007-08-01

    Full Text Available There has been considerable interest in the development of novel compounds with anticonvulsant, antidepressant, analgesic, antiinflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and antischistosomiasis activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazones that possess varied biological activities.

  19. US Competitiveness in Synthetic Biology.

    Science.gov (United States)

    Gronvall, Gigi Kwik

    2015-01-01

    Synthetic biology is an emerging technical field that aims to make biology easier to engineer; the field has applications in strategically important sectors for the US economy. While the United States currently leads in synthetic biology R&D, other nations are heavily investing in order to boost their economies, which will inevitably diminish the US leadership position. This outcome is not entirely negative--additional investments will expand markets--but it is critical that the US government take steps to remain competitive: There are applications from which the US population and economy may benefit; there are specific applications with importance for national defense; and US technical leadership will ensure that US experts have a leading role in synthetic biology governance, regulation, and oversight. Measures to increase competitiveness in S&T generally are broadly applicable for synthetic biology and should be pursued. However, the US government will also need to take action on fundamental issues that will affect the field's development, such as countering anti-GMO (genetically modified organism) sentiments and anti-GMO legislation. The United States should maintain its regulatory approach so that it is the product that is regulated, not the method used to create a product. At the same time, the United States needs to ensure that the regulatory framework is updated so that synthetic biology products do not fall into regulatory gaps. Finally, the United States needs to pay close attention to how synthetic biology applications may be governed internationally, such as through the Nagoya Protocol of the Convention on Biological Diversity, so that beneficial applications may be realized.

  20. Biological and microbial fuel cells

    OpenAIRE

    Scott, Keith; Yu, Eileen Hao; Ghangrekar, Makarand Madhao; Erable, Benjamin; Duţeanu, Narcis Mihai

    2012-01-01

    Biological fuel cells have attracted increasing interest in recent years because of their applications in environmental treatment, energy recovery, and small-scale power sources. Biological fuel cells are capable of producing electricity in the same way as a chemical fuel cell: there is a constant supply of fuel into the anode and a constant supply of oxidant into the cathode; however, typically the fuel is a hydrocarbon compound present in the wastewater, for example. Microbial fuel cells (M...