Science.gov

Sample records for biochemical evolution iii

  1. Biochemical and Structural Properties of Mouse Kynurenine Aminotransferase III

    SciTech Connect

    Han, Q.; Robinson, H; Cai, T; Tagle, D; Li, J

    2009-01-01

    Kynurenine aminotransferase III (KAT III) has been considered to be involved in the production of mammalian brain kynurenic acid (KYNA), which plays an important role in protecting neurons from overstimulation by excitatory neurotransmitters. The enzyme was identified based on its high sequence identity with mammalian KAT I, but its activity toward kynurenine and its structural characteristics have not been established. In this study, the biochemical and structural properties of mouse KAT III (mKAT III) were determined. Specifically, mKAT III cDNA was amplified from a mouse brain cDNA library, and its recombinant protein was expressed in an insect cell protein expression system. We established that mKAT III is able to efficiently catalyze the transamination of kynurenine to KYNA and has optimum activity at relatively basic conditions of around pH 9.0 and at relatively high temperatures of 50 to 60C. In addition, mKAT III is active toward a number of other amino acids. Its activity toward kynurenine is significantly decreased in the presence of methionine, histidine, glutamine, leucine, cysteine, and 3-hydroxykynurenine. Through macromolecular crystallography, we determined the mKAT III crystal structure and its structures in complex with kynurenine and glutamine. Structural analysis revealed the overall architecture of mKAT III and its cofactor binding site and active center residues. This is the first report concerning the biochemical characteristics and crystal structures of KAT III enzymes and provides a basis toward understanding the overall physiological role of mammalian KAT III in vivo and insight into regulating the levels of endogenous KYNA through modulation of the enzyme in the mouse brain.

  2. Biochemical and structural properties of mouse kynurenine aminotransferase III.

    PubMed

    Han, Qian; Robinson, Howard; Cai, Tao; Tagle, Danilo A; Li, Jianyong

    2009-02-01

    Kynurenine aminotransferase III (KAT III) has been considered to be involved in the production of mammalian brain kynurenic acid (KYNA), which plays an important role in protecting neurons from overstimulation by excitatory neurotransmitters. The enzyme was identified based on its high sequence identity with mammalian KAT I, but its activity toward kynurenine and its structural characteristics have not been established. In this study, the biochemical and structural properties of mouse KAT III (mKAT III) were determined. Specifically, mKAT III cDNA was amplified from a mouse brain cDNA library, and its recombinant protein was expressed in an insect cell protein expression system. We established that mKAT III is able to efficiently catalyze the transamination of kynurenine to KYNA and has optimum activity at relatively basic conditions of around pH 9.0 and at relatively high temperatures of 50 to 60 degrees C. In addition, mKAT III is active toward a number of other amino acids. Its activity toward kynurenine is significantly decreased in the presence of methionine, histidine, glutamine, leucine, cysteine, and 3-hydroxykynurenine. Through macromolecular crystallography, we determined the mKAT III crystal structure and its structures in complex with kynurenine and glutamine. Structural analysis revealed the overall architecture of mKAT III and its cofactor binding site and active center residues. This is the first report concerning the biochemical characteristics and crystal structures of KAT III enzymes and provides a basis toward understanding the overall physiological role of mammalian KAT III in vivo and insight into regulating the levels of endogenous KYNA through modulation of the enzyme in the mouse brain.

  3. Biochemical Lab Activity Supports Evolution Theory

    ERIC Educational Resources Information Center

    Dyman, Daniel J.

    1974-01-01

    Described is thin-layer chromatography (TLC), a technique that can be conveniently used in the laboratory to generate evidence supporting the principle that degrees of biochemical similarity reflect degrees of evolutionary relatedness among organisms. (Author/PEB)

  4. Galapagos III World Evolution Summit: why evolution matters

    PubMed Central

    Paz-y-Miño-C, Guillermo; Espinosa, Avelina

    2016-01-01

    There is no place on Earth like the Galapagos Islands and no better destination to discuss the reality of evolution. Under the theme ‘Why Does Evolution Matter’, the University San Francisco of Quito (USFQ), Ecuador, and its Galapagos Institute for the Arts and Sciences (GAIAS), organized the III World Evolution Summit in San Cristóbal Island. The 200-attendee meeting took place on 1 to 5 June 2013; it included 12 keynote speakers, 20 oral presentations by international scholars, and 31 posters by faculty, postdocs, and graduate and undergraduate students. The Summit encompassed five sessions: evolution and society, pre-cellular evolution and the RNA world, behavior and environment, genome, and microbes and diseases. USFQ and GAIAS launched officially the Lynn Margulis Center for Evolutionary Biology and showcased the Galapagos Science Center, in San Cristóbal, an impressive research facility conceptualized in partnership with the University of North Carolina at Chapel Hill, USA. USFQ and GAIAS excelled at managing the conference with exceptional vision and at highlighting the relevance of Galapagos in the history of modern evolutionary thinking; Charles Darwin’s visit to this volcanic archipelago in 1835 unfolded unprecedented scientific interest in what today is a matchless World Heritage. PMID:26925190

  5. Galapagos III World Evolution Summit: why evolution matters.

    PubMed

    Paz-Y-Miño-C, Guillermo; Espinosa, Avelina

    There is no place on Earth like the Galapagos Islands and no better destination to discuss the reality of evolution. Under the theme 'Why Does Evolution Matter', the University San Francisco of Quito (USFQ), Ecuador, and its Galapagos Institute for the Arts and Sciences (GAIAS), organized the III World Evolution Summit in San Cristóbal Island. The 200-attendee meeting took place on 1 to 5 June 2013; it included 12 keynote speakers, 20 oral presentations by international scholars, and 31 posters by faculty, postdocs, and graduate and undergraduate students. The Summit encompassed five sessions: evolution and society, pre-cellular evolution and the RNA world, behavior and environment, genome, and microbes and diseases. USFQ and GAIAS launched officially the Lynn Margulis Center for Evolutionary Biology and showcased the Galapagos Science Center, in San Cristóbal, an impressive research facility conceptualized in partnership with the University of North Carolina at Chapel Hill, USA. USFQ and GAIAS excelled at managing the conference with exceptional vision and at highlighting the relevance of Galapagos in the history of modern evolutionary thinking; Charles Darwin's visit to this volcanic archipelago in 1835 unfolded unprecedented scientific interest in what today is a matchless World Heritage.

  6. Characterization of the biochemical properties of Campylobacter jejuni RNase III

    PubMed Central

    Haddad, Nabila; Saramago, Margarida; Matos, Rute G.; Prévost, Hervé; Arraiano, Cecília M.

    2013-01-01

    Campylobacter jejuni is a foodborne bacterial pathogen, which is now considered as a leading cause of human bacterial gastroenteritis. The information regarding ribonucleases in C. jejuni is very scarce but there are hints that they can be instrumental in virulence mechanisms. Namely, PNPase (polynucleotide phosphorylase) was shown to allow survival of C. jejuni in refrigerated conditions, to facilitate bacterial swimming, cell adhesion, colonization and invasion. In several microorganisms PNPase synthesis is auto-controlled in an RNase III (ribonuclease III)-dependent mechanism. Thereby, we have cloned, overexpressed, purified and characterized Cj-RNase III (C. jejuni RNase III). We have demonstrated that Cj-RNase III is able to complement an Escherichia coli rnc-deficient strain in 30S rRNA processing and PNPase regulation. Cj-RNase III was shown to be active in an unexpectedly large range of conditions, and Mn2+ seems to be its preferred co-factor, contrarily to what was described for other RNase III orthologues. The results lead us to speculate that Cj-RNase III may have an important role under a Mn2+-rich environment. Mutational analysis strengthened the function of some residues in the catalytic mechanism of action of RNase III, which was shown to be conserved. PMID:24073828

  7. Characterization of the biochemical properties of Campylobacter jejuni RNase III.

    PubMed

    Haddad, Nabila; Saramago, Margarida; Matos, Rute G; Prévost, Hervé; Arraiano, Cecília M

    2013-11-25

    Campylobacter jejuni is a foodborne bacterial pathogen, which is now considered as a leading cause of human bacterial gastroenteritis. The information regarding ribonucleases in C. jejuni is very scarce but there are hints that they can be instrumental in virulence mechanisms. Namely, PNPase (polynucleotide phosphorylase) was shown to allow survival of C. jejuni in refrigerated conditions, to facilitate bacterial swimming, cell adhesion, colonization and invasion. In several microorganisms PNPase synthesis is auto-controlled in an RNase III (ribonuclease III)-dependent mechanism. Thereby, we have cloned, overexpressed, purified and characterized Cj-RNase III (C. jejuni RNase III). We have demonstrated that Cj-RNase III is able to complement an Escherichia coli rnc-deficient strain in 30S rRNA processing and PNPase regulation. Cj-RNase III was shown to be active in an unexpectedly large range of conditions, and Mn2+ seems to be its preferred co-factor, contrarily to what was described for other RNase III orthologues. The results lead us to speculate that Cj-RNase III may have an important role under a Mn2+-rich environment. Mutational analysis strengthened the function of some residues in the catalytic mechanism of action of RNase III, which was shown to be conserved.

  8. Plant Actin-Depolymerizing Factors Possess Opposing Biochemical Properties Arising from Key Amino Acid Changes throughout Evolution.

    PubMed

    Nan, Qiong; Qian, Dong; Niu, Yue; He, Yongxing; Tong, Shaofei; Niu, Zhimin; Ma, Jianchao; Yang, Yang; An, Lizhe; Wan, Dongshi; Xiang, Yun

    2017-02-01

    Functional divergence in paralogs is an important genetic source of evolutionary innovation. Actin-depolymerizing factors (ADFs) are among the most important actin binding proteins and are involved in generating and remodeling actin cytoskeletal architecture via their conserved F-actin severing or depolymerizing activity. In plants, ADFs coevolved with actin, but their biochemical properties are diverse. Unfortunately, the biochemical function of most plant ADFs and the potential mechanisms of their functional divergence remain unclear. Here, in vitro biochemical analyses demonstrated that all 11 ADF genes in Arabidopsis thaliana exhibit opposing biochemical properties. Subclass III ADFs evolved F-actin bundling (B-type) function from conserved F-actin depolymerizing (D-type) function, and subclass I ADFs have enhanced D-type function. By tracking historical mutation sites on ancestral proteins, several fundamental amino acid residues affecting the biochemical functions of these proteins were identified in Arabidopsis and various plants, suggesting that the biochemical divergence of ADFs has been conserved during the evolution of angiosperm plants. Importantly, N-terminal extensions on subclass III ADFs that arose from intron-sliding events are indispensable for the alteration of D-type to B-type function. We conclude that the evolution of these N-terminal extensions and several conserved mutations produced the diverse biochemical functions of plant ADFs from a putative ancestor.

  9. Plant Actin-Depolymerizing Factors Possess Opposing Biochemical Properties Arising from Key Amino Acid Changes throughout Evolution[OPEN

    PubMed Central

    Nan, Qiong; Niu, Yue; He, Yongxing; Tong, Shaofei; Niu, Zhimin; Ma, Jianchao; Yang, Yang; An, Lizhe; Wan, Dongshi

    2017-01-01

    Functional divergence in paralogs is an important genetic source of evolutionary innovation. Actin-depolymerizing factors (ADFs) are among the most important actin binding proteins and are involved in generating and remodeling actin cytoskeletal architecture via their conserved F-actin severing or depolymerizing activity. In plants, ADFs coevolved with actin, but their biochemical properties are diverse. Unfortunately, the biochemical function of most plant ADFs and the potential mechanisms of their functional divergence remain unclear. Here, in vitro biochemical analyses demonstrated that all 11 ADF genes in Arabidopsis thaliana exhibit opposing biochemical properties. Subclass III ADFs evolved F-actin bundling (B-type) function from conserved F-actin depolymerizing (D-type) function, and subclass I ADFs have enhanced D-type function. By tracking historical mutation sites on ancestral proteins, several fundamental amino acid residues affecting the biochemical functions of these proteins were identified in Arabidopsis and various plants, suggesting that the biochemical divergence of ADFs has been conserved during the evolution of angiosperm plants. Importantly, N-terminal extensions on subclass III ADFs that arose from intron-sliding events are indispensable for the alteration of D-type to B-type function. We conclude that the evolution of these N-terminal extensions and several conserved mutations produced the diverse biochemical functions of plant ADFs from a putative ancestor. PMID:28123105

  10. Canine Antithrombin-III: Some Biochemical and Biologic Properties

    DTIC Science & Technology

    1987-06-02

    4. Radial Immunodiffusion Immunologic quantitation of AT-III in normal dog plasma was assessed by radial immunodiffusion as described by Mancini ...appears to be an almost. perfect homology to the human product. D. IMMUNOLOGIC QUANTITATrON OF CANINE AT-III The radial immunodiffusion of Mancini ... Mancini , G., Carbonara, A.Q., Hermans, J.F.: Immunochemical quantitation of antigens by single radial immunodiffusion . Internat. J. Immunochem. 2:235

  11. In silico evolution of oscillatory dynamics in biochemical networks

    NASA Astrophysics Data System (ADS)

    Ali, Md Zulfikar; Wingreen, Ned S.; Mukhopadhyay, Ranjan

    2015-03-01

    We are studying in silico evolution of complex, oscillatory network dynamics within the framework of a minimal mutational model of protein-protein interactions. In our model we consider two different types of proteins, kinase (activator) and phosphatase(inhibitor). In our model. each protein can either be phosphorylated(active) or unphospphorylated (inactive), represented by binary strings. Active proteins can modify their target based on the Michaelis-Menten kinetics of chemical equation. Reaction rate constants are directly related to sequence dependent protein-protein interaction energies. This model can be stuided for non-trivial behavior e.g. oscillations, chaos, multiple stable states. We focus here on biochemical oscillators; some questions we will address within our framework include how the oscillatory dynamics depends on number of protein species, connectivity of the network, whether evolution can readily converge on a stable oscillator if we start with random intitial parameters, neutral evolution with additional protein components and general questions of robustness and evolavability.

  12. Evolution of Class III treatment in orthodontics.

    PubMed

    Ngan, Peter; Moon, Won

    2015-07-01

    Angle, Tweed, and Moyers classified Class III malocclusions into 3 types: pseudo, dentoalveolar, and skeletal. Clinicians have been trying to identify the best timing to intercept a Class III malocclusion that develops as early as the deciduous dentition. With microimplants as skeletal anchorage, orthopedic growth modification became more effective, and it also increased the scope of camouflage orthodontic treatment for patients who were not eligible for orthognathic surgery. However, orthodontic treatment combined with orthognathic surgery remains the only option for patients with a severe skeletal Class III malocclusion or a craniofacial anomaly. Distraction osteogenesis can now be performed intraorally at an earlier age. The surgery-first approach can minimize the length of time that the malocclusion needs to worsen before orthognathic surgery. Finally, the use of computed tomography scans for 3-dimensional diagnosis and treatment planning together with advances in imaging technology can improve the accuracy of surgical movements and the esthetic outcomes for these patients.

  13. Molecular and biochemical characterization of Tunisian patients with glycogen storage disease type III.

    PubMed

    Mili, Amira; Ben Charfeddine, Ilhem; Mamaï, Ons; Abdelhak, Sonia; Adala, Labiba; Amara, Abdelbasset; Pagliarani, Serena; Lucchiarri, Sabrina; Lucchiari, Sabrina; Ayadi, Abdelkarim; Tebib, Neji; Harbi, Abdelaziz; Bouguila, Jihene; H'Mida, Dorra; Saad, Ali; Limem, Khalifa; Comi, G P; Gribaa, Moez

    2012-03-01

    Glycogen storage disease type III (GSD III) is an autosomal recessive inborn error of metabolism caused by mutations in the glycogen debranching enzyme amylo-1,6-glucosidase gene, which is located on chromosome 1p21.2. GSD III is characterized by the storage of structurally abnormal glycogen, termed limit dextrin, in both skeletal and cardiac muscle and/or liver, with great variability in resultant organ dysfunction. The spectrum of AGL gene mutations in GSD III patients depends on ethnic group. The most prevalent mutations have been reported in the North African Jewish population and in an isolate such as the Faroe Islands. Here, we present the molecular and biochemical analyses of 22 Tunisian GSD III patients. Molecular analysis revealed three novel mutations: nonsense (Tyr1148X) and two deletions (3033_3036del AATT and 3216_3217del GA) and five known mutations: three nonsense (R864X, W1327X and W255X), a missense (R524H) and an acceptor splice-site mutation (IVS32-12A>G). Each mutation is associated to a specific haplotype. This is the first report of screening for mutations of AGL gene in the Tunisian population.

  14. Mathematical Descriptions of Biochemical Networks: Stability, Stochasticity, Evolution

    PubMed Central

    Rosenfeld, Simon

    2011-01-01

    In this paper, we review some fundamental aspects, as well as some new developments, in the emerging field of network biology. The focus of attention is placed on mathematical approaches to conceptual modeling of biomolecular networks with special emphasis on dynamic stability, stochasticity and evolution. PMID:21419158

  15. Biochemical Evolution of Iron and Copper Proteins, Substances Vital to Life

    ERIC Educational Resources Information Center

    Frieden, Earl

    1974-01-01

    Summarizes studies in the area of biochemical evolution of iron, copper, and heme proteins to provide an historical outline. Included are lists of major kinds of proteins and enzymes and charts illustrating electron flow in a cytochrome electron transport system and interconversion of jerrous to ferric ion in iron metabolism. (CC)

  16. Genes encoding Δ(8)-sphingolipid desaturase from various plants: identification, biochemical functions, and evolution.

    PubMed

    Li, Shu-Fen; Zhang, Guo-Jun; Zhang, Xue-Jin; Yuan, Jin-Hong; Deng, Chuan-Liang; Hu, Zan-Min; Gao, Wu-Jun

    2016-09-01

    ∆(8)-sphingolipid desaturase catalyzes the C8 desaturation of a long chain base, which is the characteristic structure of various complex sphingolipids. The genes of 20 ∆(8)-sphingolipid desaturases from 12 plants were identified and functionally detected by using Saccharomyces cerevisiae system to elucidate the relationship between the biochemical function and evolution of this enzyme. Results showed that the 20 genes all can encode a functional ∆(8)-sphingolipid desaturase, which catalyzes different ratios of two products, namely, 8(Z) and 8(E)-C18-phytosphingenine. The coded enzymes could be divided into two groups on the basis of biochemical functions: ∆(8)-sphingolipid desaturase with a preference for an E-isomer product and ∆(8)-sphingolipid desaturase with a preference for a Z-isomer product. The conversion rate of the latter was generally lower than that of the former. Phylogenetic analysis revealed that the 20 desaturases could also be clustered into two groups, and this grouping is consistent with that of the biochemical functions. Thus, the biochemical function of ∆(8)-sphingolipid desaturase is correlated with its evolution. The two groups of ∆(8)-sphingolipid desaturases could arise from distinct ancestors in higher plants. However, they might have initially evolved from ∆(8)-sphingolipid desaturases in lower organisms, such as yeasts, which can produce E-isomer products only. Furthermore, almost all of the transgenic yeasts harboring ∆(8)-sphingolipid desaturase genes exhibit an improvement in aluminum tolerance. Our study provided new insights into the biochemical function and evolution of ∆(8)-sphingolipid desaturases in plants.

  17. The role of log-normal dynamics in the evolution of biochemical pathways.

    PubMed

    Nacher, J C; Ochiai, T; Yamada, T; Kanehisa, M; Akutsu, T

    2006-01-01

    The study of the scale-free topology in non-biological and biological networks and the dynamics that can explain this fascinating property of complex systems have captured the attention of the scientific community in the last years. Here, we analyze the biochemical pathways of three organisms (Methanococcus jannaschii, Escherichia coli, Saccharomyces cerevisiae) which are representatives of the main kingdoms Archaea, Bacteria and Eukaryotes during the course of the biological evolution. We can consider two complementary representations of the biochemical pathways: the enzymes network and the chemical compounds network. In this article, we propose a stochastic model that explains that the scale-free topology with exponent in the vicinity of gamma approximately 3/2 found across these three organisms is governed by the log-normal dynamics in the evolution of the enzymes network. Precisely, the fluctuations of the connectivity degree of enzymes in the biochemical pathways between evolutionary distant organisms follow the same conserved dynamical principle, which in the end is the origin of the stationary scale-free distribution observed among species, from Archaea to Eukaryotes. In particular, the log-normal dynamics guarantees the conservation of the scale-free distribution in evolving networks. Furthermore, the log-normal dynamics also gives a possible explanation for the restricted range of observed exponents gamma in the scale-free networks (i.e., gamma > or = 3/2). Finally, our model is also applied to the chemical compounds network of biochemical pathways and the Internet network.

  18. Hemorrhagic metalloproteinase, Cc HSM-III, isolated from Cerastes cerastes venom: Purification and biochemical characterization.

    PubMed

    Tachoua, Wafa; Boukhalfa-Abib, Hinda; Laraba-Djebari, Fatima

    2017-02-28

    Snake venom metalloproteinases are the most abundant toxins in Viperidae venoms. In this study, a new hemorrhagin, Cc HSM-III (66 kDa), was purified from Cerastes cerastes venom by gel filtration, ion exchange, and reversed-phase high-performance liquid chromatographies. The analysis of Cc HSM-III by liquid chromatography with a tandem mass spectrometry revealed 32 peptides sharing a homology with P-III metalloproteinases from Echis ocellatus snake venom. Cc HSM-III displays hemorrhagic activity with a minimal hemorrhagic dose of 5 μg, which is abolished by ethylene diamine tetracetic acid but not by phenylmethylsulfonyl fluoride. The mechanism underlying Cc HSM-III hemorrhagic activity is probably due to its extensive proteolytic activity against type IV collagen. Cc HSM-III induces local tissue damage and an inflammatory response by upregulating both matrix metalloproteinase 2 and 9 in skin of mice. Thus, Cc HSM-III may play a key role in the pathogenesis of C. cerastes envenomation.

  19. Physiological and biochemical responses of Eichhornia crassipes exposed to Cr (III).

    PubMed

    González, C I; Maine, M A; Cazenave, J; Sanchez, G C; Benavides, M P

    2015-03-01

    The effect of exposure of Eichhornia crassipes to Cr (III) was assessed by measuring changes in photosynthetic pigments, malondialdehyde, superoxide dismutase, glutathione reductase, catalase, and guaiacol peroxidase activities, as well as Cr concentration in tissues. Cr concentration in roots was significantly higher than in aerial parts and increased with Cr concentration in water. Photosynthetic pigments increased significantly, whereas the activities of antioxidant enzymes varied differently in plant tissues. Low Cr concentrations induced a rapid response of E. crassipes during short-term exposure, implying that the antioxidant system conferred redox homeostasis. Results showed that Cr (III) was more toxic at the two highest concentrations and long-term exposure, while it was not harmful but beneficial at the two lowest concentrations and short-term exposure. This work concludes that E. crassipes was able to grow under Cr (III) stress by protecting itself with an increase in the activity of its antioxidant system.

  20. Diversity of bile salts in fish and amphibians: evolution of a complex biochemical pathway.

    PubMed

    Hagey, Lee R; Møller, Peter R; Hofmann, Alan F; Krasowski, Matthew D

    2010-01-01

    Bile salts are the major end metabolites of cholesterol and are also important in lipid and protein digestion, as well as shaping of the gut microflora. Previous studies had demonstrated variation of bile salt structures across vertebrate species. We greatly extend prior surveys of bile salt variation in fish and amphibians, particularly in analysis of the biliary bile salts of Agnatha and Chondrichthyes. While there is significant structural variation of bile salts across all fish orders, bile salt profiles are generally stable within orders of fish and do not correlate with differences in diet. This large data set allowed us to infer evolutionary changes in the bile salt synthetic pathway. The hypothesized ancestral bile salt synthetic pathway, likely exemplified in extant hagfish, is simpler and much shorter than the pathway of most teleost fish and terrestrial vertebrates. Thus, the bile salt synthetic pathway has become longer and more complex throughout vertebrate evolution. Analysis of the evolution of bile salt synthetic pathways provides a rich model system for the molecular evolution of a complex biochemical pathway in vertebrates.

  1. From molecules to mating: Rapid evolution and biochemical studies of reproductive proteins

    PubMed Central

    Wilburn, Damien B.; Swanson, Willie J.

    2015-01-01

    Sexual reproduction and the exchange of genetic information are essential biological processes for species across all branches of the tree of life. Over the last four decades, biochemists have continued to identify many of the factors that facilitate reproduction, but the molecular mechanisms that mediate this process continue to elude us. However, a recurring observation in this research has been the rapid evolution of reproductive proteins. In animals, the competing interests of males and females often result in arms race dynamics between pairs of interacting proteins. This phenomenon has been observed in all stages of reproduction, including pheromones, seminal fluid components, and gamete recognition proteins. In this article, we review how the integration of evolutionary theory with biochemical experiments can be used to study interacting reproductive proteins. Examples are included from both model and non-model organisms, and recent studies are highlighted for their use of state-of-the-art genomic and proteomic techniques. Significance Despite decades of research, our understanding of the molecular mechanisms that mediate fertilization remain poorly characterized. To date, molecular evolutionary studies on both model and non-model organisms have provided some of the best inferences to elucidating the molecular underpinnings of animal reproduction. This review article details how biochemical and evolutionary experiments have jointly enhanced the field for 40 years, and how recent work using high-throughput genomic and proteomic techniques have shed additional insights into this crucial biological process. PMID:26074353

  2. The evolution of galaxies. III - Metal-enhanced star formation

    NASA Technical Reports Server (NTRS)

    Talbot, R. J., Jr.; Arnett, W. D.

    1973-01-01

    The problem of the paucity of low-metal-abundance low-mass stars is discussed. One alternative to the variable-initial-mass-function (VIMF) solution is proposed. It is shown that this solution - metal-enhanced star formation - satisfies the classical test which prompted the VIMF hypothesis. Furthermore, with no additional parameters it provides improved fits to other tests - e.g., inhomogeneities in the abundances in young stars, concordance of all nucleo-cosmochronologies, and a required yield of heavy-element production which is consistent with current stellar evolution theory. In this model the age of the Galaxy is 18.6 plus or minus 5.7 b.y.

  3. Pele III, plate tectonics, atmospheric and biotic evolution

    SciTech Connect

    Sloan, R.E. . Dept. of Geology and Geophysics)

    1994-04-01

    This paper is an elaboration of Pele I and II, Landis et al GSA Abstr. V. 25 No.6, and Hengst et al GSA Abstr. V. 25 No.6. The Pele hypothesis is that CO[sub 2] concentration in the atmosphere is directly related to the rate of seafloor spreading and the existence of superplumes. Excess CO[sub 2] favors expansion of plants and is converted to O[sub 2] by photosynthesis and deposition of buried carbon and carbonate. O[sub 2] is removed from the atmosphere by weathering. Resulting major variations in atmospheric CO[sub 2] and O[sub 2] have significant impact on the evolution and extinction of organisms.

  4. An alternative splicing event which occurs in mouse pachytene spermatocytes generates a form of DNA ligase III with distinct biochemical properties that may function in meiotic recombination.

    PubMed Central

    Mackey, Z B; Ramos, W; Levin, D S; Walter, C A; McCarrey, J R; Tomkinson, A E

    1997-01-01

    Three mammalian genes encoding DNA ligases have been identified. However, the role of each of these enzymes in mammalian DNA metabolism has not been established. In this study, we show that two forms of mammalian DNA ligase III, alpha and beta, are produced by a conserved tissue-specific alternative splicing mechanism involving exons encoding the C termini of the polypeptides. DNA ligase III-alpha cDNA, which encodes a 103-kDa polypeptide, is expressed in all tissues and cells, whereas DNA ligase III-beta cDNA, which encodes a 96-kDa polypeptide, is expressed only in the testis. During male germ cell differentiation, elevated expression of DNA ligase III-beta mRNA is restricted, beginning only in the latter stages of meiotic prophase and ending in the round spermatid stage. In 96-kDa DNA ligase III-beta, the C-terminal 77 amino acids of DNA ligase III-alpha are replaced by a different 17- to 18-amino acid sequence. As reported previously, the 103-kDa DNA ligase III-alpha interacts with the DNA strand break repair protein encoded by the human XRCC1 gene. In contrast, the 96-kDa DNA ligase III-beta does not interact with XRCC1, indicating that DNA ligase III-beta may play a role in cellular functions distinct from the DNA repair pathways involving the DNA ligase III-alpha x XRCC1 complex. The distinct biochemical properties of DNA ligase III-beta, in combination with the tissue- and cell-type-specific expression of DNA ligase III-beta mRNA, suggest that this form of DNA ligase III is specifically involved in the completion of homologous recombination events that occur during meiotic prophase. PMID:9001252

  5. Biochemical evolution II: origin of life in tubular microstructures on weathered feldspar surfaces.

    PubMed

    Parsons, I; Lee, M R; Smith, J V

    1998-12-22

    Mineral surfaces were important during the emergence of life on Earth because the assembly of the necessary complex biomolecules by random collisions in dilute aqueous solutions is implausible. Most silicate mineral surfaces are hydrophilic and organophobic and unsuitable for catalytic reactions, but some silica-rich surfaces of partly dealuminated feldspars and zeolites are organophilic and potentially catalytic. Weathered alkali feldspar crystals from granitic rocks at Shap, north west England, contain abundant tubular etch pits, typically 0.4-0.6 microm wide, forming an orthogonal honeycomb network in a surface zone 50 microm thick, with 2-3 x 10(6) intersections per mm2 of crystal surface. Surviving metamorphic rocks demonstrate that granites and acidic surface water were present on the Earth's surface by approximately 3.8 Ga. By analogy with Shap granite, honeycombed feldspar has considerable potential as a natural catalytic surface for the start of biochemical evolution. Biomolecules should have become available by catalysis of amino acids, etc. The honeycomb would have provided access to various mineral inclusions in the feldspar, particularly apatite and oxides, which contain phosphorus and transition metals necessary for energetic life. The organized environment would have protected complex molecules from dispersion into dilute solutions, from hydrolysis, and from UV radiation. Sub-micrometer tubes in the honeycomb might have acted as rudimentary cell walls for proto-organisms, which ultimately evolved a lipid lid giving further shelter from the hostile outside environment. A lid would finally have become a complete cell wall permitting detachment and flotation in primordial "soup." Etch features on weathered alkali feldspar from Shap match the shape of overlying soil bacteria.

  6. Bacterial flagella and Type III secretion: case studies in the evolution of complexity.

    PubMed

    Pallen, M J; Gophna, U

    2007-01-01

    Bacterial flagella at first sight appear uniquely sophisticated in structure, so much so that they have even been considered 'irreducibly complex' by the intelligent design movement. However, a more detailed analysis reveals that these remarkable pieces of molecular machinery are the product of processes that are fully compatible with Darwinian evolution. In this chapter we present evidence for such processes, based on a review of experimental studies, molecular phylogeny and microbial genomics. Several processes have played important roles in flagellar evolution: self-assembly of simple repeating subunits, gene duplication with subsequent divergence, recruitment of elements from other systems ('molecular bricolage'), and recombination. We also discuss additional tentative new assignments of homology (FliG with MgtE, FliO with YscJ). In conclusion, rather than providing evidence of intelligent design, flagellar and non-flagellar Type III secretion systems instead provide excellent case studies in the evolution of complex systems from simpler components.

  7. Aging as Evolution-Facilitating Program and a Biochemical Approach to Switch It Off

    NASA Astrophysics Data System (ADS)

    Skulachev, Vladimir P.

    A concept is presented considering aging of living organisms as a final step of their ontogenetic program. It is assumed that such an aging program was invented by biological evolution to facilitate the evolutionary process. Indications are summarized suggesting that controlled production of toxic forms of oxygen (so called reactive oxygen species) by respiring intracellular organelles (mitochondria) is an obligatory component of the aging program. First results of a research project devoted to an attempt to interrupt aging program by antioxidants specifically addressed to mitochondria have been described. Within the framework of the project, antioxidants of a new type (SkQ) were synthesized. SkQs are composed of (i) plastoquinone (an antioxidant moiety), (ii) a penetrating cation, and (iii) a decane or pentane linker. Using planar bilayer phospholipid membranes, we selected SkQ derivatives of the highest penetrability, namely plastoquinonyl decyl triphenylphosphonium (SkQ1), plastoquinonyl decyl rhodamine 19 (SkQR1), and methylplastoquinonyl decyl triphenylphosphonium (SkQ3). Anti- and prooxidant properties of these substances and also of ubiquinonyl-decyl-triphenylphosphonium (MitoQ) were tested in isolated mitochondria. Micromolar concentrations of cationic quinones are found to be very strong prooxidants, but in the lower (sub-micromolar) concentrations they display antioxidant activity which decreases in the series SkQ1 = SkQR1 > SkQ3 > MitoQ. Thus, the window between the anti- and prooxidant effects is the smallest for MitoQ and the largest for SkQ1 and SkQR1. SkQ1 is rapidly reduced by complex III of the mitochondrial respiratory chain, i.e. it is a rechargeable antioxidant. Extremely low concentrations of SkQ1 and SkQR1 completely arrest the H2O2-induced apoptosis in human fibroblasts and HeLa cells (for SkQ1, C 1/2 = 8 · 10-9M). Higher concentrations of SkQ1 are required to block necrosis initiated by reactive oxygen species (ROS). In mice, SkQ1

  8. Evolution, biogeography, and systematics of Puriana: evolution and speciation in Ostracoda, III.

    USGS Publications Warehouse

    Cronin, T. M.

    1987-01-01

    Three types of geographic isolation - land barriers, deep water barriers, and climatic barriers - resulted in three distinct evolutionary responses in Neogene and Quaternary species of the epineritic ostracode genus Puriana. Through systematic, paleobiogeographic, and morphologic study of several hundred fossil and Recent populations from the eastern Pacific, western Atlantic, Gulf of Mexico, and the Caribbean, the phylogeny of the genus and the geography of speciation events were determined. Isolation of large populations by the Isthumus of Panama during the Pliocene did not lead to lineage splitting in species known to have existed before the Isthmus formed. Conversely, the establishment of small isolated populations on Caribbean islands by passive dispersal mechanisms frequently led to the evolution of new species or subspecies. Climatic changes along the southeastern United States during the Pliocene also catalyzed possible parapatric speciation as populations that immigrated to the northeastern periphery of the genus' range split to form new species. The results provide evidence that evolutionary models describing the influence of abiotic events on patterns of evolution and speciation can be tested using properly selected tectonic and climatic events and fossil groups amenable to species-level analysis. Two new species, P. bajaensis and P. paikensis, are described. -Author

  9. SIM-GC-MS analysis of biochemical evolution in Amanita genus

    NASA Astrophysics Data System (ADS)

    Ristoiu, Dumitru; Kovacs, Emoke Dalma; Cobzac, Codruta; Parvu, Marcel; Ristoiu, Tania; Kovacs, Melinda Haydee

    2010-11-01

    Amanita is one of the most well known basidiomycetes genus throughout the world because some of its species that are acknowledged due to their toxic and/or hallucinogenic properties. Considering these properties in the last decades become more important for scientist to dignify exactly the chemical content of these mushroom species. Latter researches shown that A. phalloides contain two main groups of toxins: the amatoxins and the phallotoxins. As regards A. rubescens there are not so much studies referring to its biochemical "fingerprint". Two species (A. rubescens and A. phalloides) of Amanita genus were studied in order to determine the biochemical hall-mark at nanoscale for these basidiomycete's species. Parts as caps, gills, flesh and stem of these mushrooms were analyzed on quadrupole mass spectrometer engaged with a gas chromatograph (GC-qMS) using selective ion monitoring mode (SIM). The biochemical profiles of these species had shown the presence of compounds like fatty acid methyl esters (FAMEs), alkaloids, and volatile compounds (including alcohol compounds, carbonyl compounds, terpenes). The levels of biochemical compounds from these species were compared between the two types of species and also between young, mature and old samples for the same species as well as between the parts of mushroom. After this comparison were between the two species it was observed that in case of A. phalloides the alkaloid content were higher usually with almost 50 %. As regards presence of volatile compounds they have almost similar level in both mushroom species. Considering the levels of fatty acid methyl esters, their levels were higher with 30 - 40 % in case of A. rubescens.

  10. Comparative biochemical characterization of peroxidases (class III) tightly bound to the maize root cell walls and modulation of the enzyme properties as a result of covalent binding.

    PubMed

    Hadži-Tašković Šukalović, Vesna; Vuletić, Mirjana; Marković, Ksenija; Cvetić Antić, Tijana; Vučinić, Željko

    2015-01-01

    Comparative biochemical characterization of class III peroxidase activity tightly bound to the cell walls of maize roots was performed. Ionically bound proteins were solubilized from isolated walls by salt washing, and the remaining covalently bound peroxidases were released, either by enzymatic digestion or by a novel alkaline extraction procedure that released covalently bound alkali-resistant peroxidase enzyme. Solubilized fractions, as well as the salt-washed cell wall fragments containing covalently bound proteins, were analyzed for peroxidase activity. Peroxidative and oxidative activities indicated that peroxidase enzymes were predominately associated with walls by ionic interactions, and this fraction differs from the covalently bound one according to molecular weight, isozyme patterns, and biochemical parameters. The effect of covalent binding was evaluated by comparison of the catalytic properties of the enzyme bound to the salt-washed cell wall fragments with the corresponding solubilized and released enzyme. Higher thermal stability, improved resistance to KCN, increased susceptibility to H2O2, stimulated capacity of wall-bound enzyme to oxidize indole-3-acetic acid (IAA) as well as the difference in kinetic parameters between free and bound enzymes point to conformational changes due to covalent binding. Differences in biochemical properties of ionically and covalently bound peroxidases, as well as the modulation of the enzyme properties as a result of covalent binding to the walls, indicate that these two fractions of apoplastic peroxidases play different roles.

  11. Modular evolution of glutathione peroxidase genes in association with different biochemical properties of their encoded proteins in invertebrate animals

    PubMed Central

    Bae, Young-An; Cai, Guo-Bin; Kim, Seon-Hee; Zo, Young-Gun; Kong, Yoon

    2009-01-01

    Background Phospholipid hydroperoxide glutathione peroxidases (PHGPx), the most abundant isoforms of GPx families, interfere directly with hydroperoxidation of lipids. Biochemical properties of these proteins vary along with their donor organisms, which has complicated the phylogenetic classification of diverse PHGPx-like proteins. Despite efforts for comprehensive analyses, the evolutionary aspects of GPx genes in invertebrates remain largely unknown. Results We isolated GPx homologs via in silico screening of genomic and/or expressed sequence tag databases of eukaryotic organisms including protostomian species. Genes showing strong similarity to the mammalian PHGPx genes were commonly found in all genomes examined. GPx3- and GPx7-like genes were additionally detected from nematodes and platyhelminths, respectively. The overall distribution of the PHGPx-like proteins with different biochemical properties was biased across taxa; selenium- and glutathione (GSH)-dependent proteins were exclusively detected in platyhelminth and deuterostomian species, whereas selenium-independent and thioredoxin (Trx)-dependent enzymes were isolated in the other taxa. In comparison of genomic organization, the GSH-dependent PHGPx genes showed a conserved architectural pattern, while their Trx-dependent counterparts displayed complex exon-intron structures. A codon for the resolving Cys engaged in reductant binding was found to be substituted in a series of genes. Selection pressure to maintain the selenocysteine codon in GSH-dependent genes also appeared to be relaxed during their evolution. With the dichotomized fashion in genomic organizations, a highly polytomic topology of their phylogenetic trees implied that the GPx genes have multiple evolutionary intermediate forms. Conclusion Comparative analysis of invertebrate GPx genes provides informative evidence to support the modular pathways of GPx evolution, which have been accompanied with sporadic expansion/deletion and exon

  12. Morphology evolution of gold nanoparticles as function of time, temperature, and Au(III)/sodium ascorbate molar ratio

    NASA Astrophysics Data System (ADS)

    Priolisi, Ornella; Fabrizi, Alberto; Deon, Giovanna; Bonollo, Franco; Cattini, Stefano

    2016-01-01

    In this work the morphology evolution of Au nanoparticles (AuNPs), obtained by direct reduction, was studied as a function of time, temperature, and Au(III)/sodium ascorbate molar ratio. The NPs morphology was examined by transmission electron microscope with image analysis, while time evolution was investigated by visible and near-infrared absorption spectroscopy and dynamic light scattering. It is found that initially formed star-like NPs transform in more spheroidal particles and the evolution appears more rapid by increasing the temperature while a large amount of reducing agent prevents the remodeling of AuNPs. An explication of morphology evolution is proposed.

  13. Evidence from Biochemical Pathways in Favor of Unfinished Evolution Rather than Intelligent Design

    ERIC Educational Resources Information Center

    Behrman, Edward J.; Marzluf, George A.

    2004-01-01

    An argument is made in favor of imperfect or unfinished evolution based on some metabolic pathways in which it seems that intelligent design would have done better. The case studies noted indicate the absence of highly intelligent design and are not intended as comprehensive collection but as a limited sample of inefficient situations in…

  14. Redshift evolution of the dynamical properties of massive galaxies from SDSS-III/BOSS

    SciTech Connect

    Beifiori, Alessandra; Saglia, Roberto P.; Bender, Ralf; Senger, Robert; Thomas, Daniel; Maraston, Claudia; Steele, Oliver; Masters, Karen L.; Pforr, Janine; Tojeiro, Rita; Johansson, Jonas; Nichol, Robert C.; Chen, Yan-Mei; Wake, David; Bolton, Adam; Brownstein, Joel R.; Leauthaud, Alexie; Schneider, Donald P.; Skibba, Ramin; Pan, Kaike; and others

    2014-07-10

    We study the redshift evolution of the dynamical properties of ∼180, 000 massive galaxies from SDSS-III/BOSS combined with a local early-type galaxy sample from SDSS-II in the redshift range 0.1 ≤ z ≤ 0.6. The typical stellar mass of this sample is M{sub *} ∼2 × 10{sup 11} M{sub ☉}. We analyze the evolution of the galaxy parameters effective radius, stellar velocity dispersion, and the dynamical to stellar mass ratio with redshift. As the effective radii of BOSS galaxies at these redshifts are not well resolved in the Sloan Digital Sky Survey (SDSS) imaging we calibrate the SDSS size measurements with Hubble Space Telescope/COSMOS photometry for a sub-sample of galaxies. We further apply a correction for progenitor bias to build a sample which consists of a coeval, passively evolving population. Systematic errors due to size correction and the calculation of dynamical mass are assessed through Monte Carlo simulations. At fixed stellar or dynamical mass, we find moderate evolution in galaxy size and stellar velocity dispersion, in agreement with previous studies. We show that this results in a decrease of the dynamical to stellar mass ratio with redshift at >2σ significance. By combining our sample with high-redshift literature data, we find that this evolution of the dynamical to stellar mass ratio continues beyond z ∼ 0.7 up to z > 2 as M{sub dyn}/M{sub *} ∼(1 + z){sup –0.30±0.12}, further strengthening the evidence for an increase of M{sub dyn}/M{sub *} with cosmic time. This result is in line with recent predictions from galaxy formation simulations based on minor merger driven mass growth, in which the dark matter fraction within the half-light radius increases with cosmic time.

  15. Biochemical investigation of yttrium(III) complex containing 1,10-phenanthroline: DNA binding and antibacterial activity.

    PubMed

    Khorasani-Motlagh, Mozhgan; Noroozifar, Meissam; Moodi, Asieh; Niroomand, Sona

    2013-03-05

    Characterization of the interaction between yttrium(III) complex containing 1,10-phenanthroline as ligand, [Y(phen)2Cl(OH2)3]Cl2⋅H2O, and DNA has been carried out by UV absorption, fluorescence spectra and viscosity measurements in order to investigate binding mode. The experimental results indicate that the yttrium(III) complex binds to DNA and absorption is decreasing in charge transfer band with the increase in amount of DNA. The binding constant (Kb) at different temperatures as well as thermodynamic parameters, enthalpy change (ΔH°) and entropy change (ΔS°), were calculated according to relevant fluorescent data and Vant' Hoff equation. The results of interaction mechanism studies, suggested that groove binding plays a major role in the binding of the complex and DNA. The activity of yttrium(III) complex against some bacteria was tested and antimicrobial screening tests shown growth inhibitory activity in the presence of yttrium(III) complex.

  16. Structural and Biochemical Characterization of SrcA, a Multi-cargo Type III Secretion Chaperone in Salmonella Required for Pathogenic Association with a Host

    SciTech Connect

    Cooper, C.; Zhang, K; Andres, S; Fnag, Y; Kaniuk, N; Hannemann, M; Brumell, J; Foster, L; Junop, M; Coombes, B

    2010-01-01

    Many Gram-negative bacteria colonize and exploit host niches using a protein apparatus called a type III secretion system (T3SS) that translocates bacterial effector proteins into host cells where their functions are essential for pathogenesis. A suite of T3SS-associated chaperone proteins bind cargo in the bacterial cytosol, establishing protein interaction networks needed for effector translocation into host cells. In Salmonella enterica serovar Typhimurium, a T3SS encoded in a large genomic island (SPI-2) is required for intracellular infection, but the chaperone complement required for effector translocation by this system is not known. Using a reverse genetics approach, we identified a multi-cargo secretion chaperone that is functionally integrated with the SPI-2-encoded T3SS and required for systemic infection in mice. Crystallographic analysis of SrcA at a resolution of 2.5 {angstrom} revealed a dimer similar to the CesT chaperone from enteropathogenic E. coli but lacking a 17-amino acid extension at the carboxyl terminus. Further biochemical and quantitative proteomics data revealed three protein interactions with SrcA, including two effector cargos (SseL and PipB2) and the type III-associated ATPase, SsaN, that increases the efficiency of effector translocation. Using competitive infections in mice we show that SrcA increases bacterial fitness during host infection, highlighting the in vivo importance of effector chaperones for the SPI-2 T3SS.

  17. LOCAL LUMINOUS INFRARED GALAXIES. III. CO-EVOLUTION OF BLACK HOLE GROWTH AND STAR FORMATION ACTIVITY?

    SciTech Connect

    Alonso-Herrero, Almudena; Hernan-Caballero, Antonio; Pereira-Santaella, Miguel; Rieke, George H.; Diamond-Stanic, Aleksandar M.; Wang Yiping; Rigopoulou, Dimitra

    2013-03-10

    Local luminous infrared (IR) galaxies (LIRGs) have both high star formation rates (SFR) and a high AGN (Seyfert and AGN/starburst composite) incidence. Therefore, they are ideal candidates to explore the co-evolution of black hole (BH) growth and star formation (SF) activity, not necessarily associated with major mergers. Here, we use Spitzer/IRS spectroscopy of a complete volume-limited sample of local LIRGs (distances of <78 Mpc). We estimate typical BH masses of 3 Multiplication-Sign 10{sup 7} M{sub Sun} using [Ne III] 15.56 {mu}m and optical [O III] {lambda}5007 gas velocity dispersions and literature stellar velocity dispersions. We find that in a large fraction of local LIRGs, the current SFR is taking place not only in the inner nuclear {approx}1.5 kpc region, as estimated from the nuclear 11.3 {mu}m PAH luminosities, but also in the host galaxy. We next use the ratios between the SFRs and BH accretion rates (BHAR) to study whether the SF activity and BH growth are contemporaneous in local LIRGs. On average, local LIRGs have SFR to BHAR ratios higher than those of optically selected Seyferts of similar active galactic nucleus (AGN) luminosities. However, the majority of the IR-bright galaxies in the revised-Shapley-Ames Seyfert sample behave like local LIRGs. Moreover, the AGN incidence tends to be higher in local LIRGs with the lowest SFRs. All of this suggests that in local LIRGs there is a distinct IR-bright star-forming phase taking place prior to the bulk of the current BH growth (i.e., AGN phase). The latter is reflected first as a composite and then as a Seyfert, and later as a non-LIRG optically identified Seyfert nucleus with moderate SF in its host galaxy.

  18. Evolution of Fseg/Cseg dimorphism in region III of the Plasmodium falciparum eba-175 gene.

    PubMed

    Yasukochi, Yoshiki; Naka, Izumi; Patarapotikul, Jintana; Hananantachai, Hathairad; Ohashi, Jun

    2017-04-01

    The 175-kDa erythrocyte binding antigen (EBA-175) of the malaria parasite Plasmodium falciparum is important for its invasion into human erythrocytes. The primary structure of eba-175 is divided into seven regions, namely I to VII. Region III contains highly divergent dimorphic segments, termed Fseg and Cseg. The allele frequencies of segmental dimorphism within a P. falciparum population have been extensively examined; however, the molecular evolution of segmental dimorphism is not well understood. A comprehensive comparison of nucleotide sequences among 32 P. falciparum eba-175 alleles identified in our previous study, two Plasmodium reichenowi, and one P. gaboni orthologous alleles obtained from the GenBank database was conducted to uncover the origin and evolutionary processes of segmental dimorphism in P. falciparum eba-175. In the eba-175 nucleotide sequence derived from a P. reichenowi CDC strain, both Fseg and Cseg were found in region III, which implies that the original eba-175 gene had both segments, and deletions of F- and C-segments generated Cseg and Fseg alleles, respectively. We also confirmed the presence of allele with Fseg and Cseg in another P. reichenowi strain (SY57), by re-mapping short reads obtained from the GenBank database. On the other hand, the segmental sequence of eba-175 ortholog in P. gaboni was quite diverged from those of the other species, suggesting that the original eba-175 dimorphism of P. falciparum can be traced back to the stem linage of P. falciparum and P. reichenowi. Our findings suggest that Fseg and Cseg alleles are derived from a single eba-175 allele containing both segments in the ancestral population of P. falciparum and P. reichenowi, and that the allelic dimorphism of eba-175 was shaped by the independent emergence of similar dimorphic lineage in different species that has never been observed in any evolutionary mode of allelic dimorphism at other loci in malaria genomes.

  19. Chemical, biochemical, and environmental fiber sensors III; Proceedings of the Meeting, Boston, MA, Sept. 4, 5, 1991

    SciTech Connect

    Lieberman, R.A.

    1992-01-01

    Various papers on chemical, biochemical, and environmental fiber sensors are presented. Individual topics addressed include: fiber optic pressure sensor for combustion monitoring and control, viologen-based fiber optic oxygen sensors, renewable-reagent fiber optic sensor for ocean pCO2, transition metal complexes as indicators for a fiber optic oxygen sensor, fiber optic pH measurements using azo indicators, simple reversible fiber optic chemical sensors using solvatochromic dyes, totally integrated optical measuring sensors, integrated optic biosensor for environmental monitoring, radiation dosimetry using planar waveguide sensors, optical and piezoelectric analysis of polymer films for chemical sensor characterization, source polarization effects in an optical fiber fluorosensor, lens-type refractometer for on-line chemical analysis, fiber optic hydrocarbon sensor system, chemical sensors for environmental monitoring, optical fibers for liquid-crystal sensing and logic devices, suitability of single-mode fluoride fibers for evanescent-wave sensing, integrated modules for fiber optic sensors, optoelectronic sensors based on narrowband A3B5 alloys, fiber Bragg grating chemical sensor.

  20. [Toxicological evaluation of colloidal nano-sized silver stabilized polyvinylpyrrolidone. III. Enzymological, biochemical markers, state of antioxidant defense system].

    PubMed

    Gmoshinsky, I V; Shipelin, V A; Vorozhko, I V; Sentsova, T B; Soto, S Kh; Avren'eva, L I; Guseva, G V; Kravchenko, L V; Khotimchenko, S A; Tutelyan, V A

    2016-01-01

    Nanosized colloidal silver (NCS) with primary nanoparticles (NPs) size in the range of 10-80 nm in aqueous suspension was administered to rats with initial weight 80±10 gfor the first 30 day intragastrically and for lasting 62 days with the diet consumed in doses of 0.1; 1.0 and 10 mg/kg of body weight b.w) per day based on silver (Ag). The control animals received deionized water and carrier of NPs - aqueous solution of stabilizer polyvinylpyrrolidone. Activity (Vmax) was determined in liver of microsomal mixed function monooxygenase isoforms CYP 1A1, 1A2 and 2B1 against their specific substrates, the activity of liver conjugating enzymes (glutathione-S-transferase and UDP-glucuronosyltransferase) in the microsomal fraction and a cytosol, and the overall and non-sedimentable activities of lysosomal hydrolases. In blood plasma there were evaluated malonic dialdehyde, PUFA diene conjugates, in erythrocytes - the activity of antioxidant enzymes. A set of standard biochemical indicators of blood serum was also determined. The studies revealed changes in a number of molecular markers of toxic action. Among them - the increase in the activity of key enzymes I and II stages of detoxification of xenobiotics, indicating its functional overvoltage; reducing the activity of glutathione peroxidase (GP), the total arylsulfatase A and B, β-galactosidase (in the absence of changes in their non-sedimentable activity), levels of uric acid, increased alkaline phosphatase activity. These changes occurred mainly at the dose Ag of 10 mg/kg b.w., except for the GP to which the threshold dose was 1 mg/kg b.w. No significant changes in the studied markers in a dose Ag 0,1 mg/kg b.w. were identified. Possible mechanisms of the toxic action of silver NPs are discussed.

  1. The evolution of increased competitive ability, innate competitive advantages, and novel biochemical weapons act in concert for a tropical invader.

    PubMed

    Qin, Rui-Min; Zheng, Yu-Long; Valiente-Banuet, Alfonso; Callaway, Ragan M; Barclay, Gregor F; Pereyra, Carlos Silva; Feng, Yu-Long

    2013-02-01

    There are many non-mutually exclusive mechanisms for exotic invasions but few studies have concurrently tested more than one hypothesis for the same species. Here, we tested the evolution of increased competitive ability (EICA) hypothesis in two common garden experiments in which Chromolaena odorata plants originating from native and nonnative ranges were grown in competition with natives from each range, and the novel weapons hypothesis in laboratory experiments with leachates from C. odorata. Compared with conspecifics originating from the native range, C. odorata plants from the nonnative range were stronger competitors at high nutrient concentrations in the nonnative range in China and experienced far more herbivore damage in the native range in Mexico. In both China and Mexico, C. odorata was more suppressed by species native to Mexico than by species native to China. Species native to China were much more inhibited by leaf extracts from C. odorata than species from Mexico, and this difference in allelopathic effects may provide a possible explanation for the biogeographic differences in competitive ability. Our results indicate that EICA, innate competitive advantages, and novel biochemical weapons may act in concert to promote invasion by C. odorata, and emphasize the importance of exploring multiple, non-mutually exclusive mechanisms for invasions.

  2. Challenging the paradigms of leaf evolution: Class III HD-Zips in ferns and lycophytes.

    PubMed

    Vasco, Alejandra; Smalls, Tynisha L; Graham, Sean W; Cooper, Endymion D; Wong, Gane Ka-Shu; Stevenson, Dennis W; Moran, Robbin C; Ambrose, Barbara A

    2016-11-01

    Despite the extraordinary significance leaves have for life on Earth, their origin and development remain vigorously debated. More than a century of paleobotanical, morphological, and phylogenetic research has still not resolved fundamental questions about leaves. Developmental genetic data are sparse in ferns, and comparative studies of lycophytes and seed plants have reached opposing conclusions on the conservation of a leaf developmental program. We performed phylogenetic and expression analyses of a leaf developmental regulator (Class III HD-Zip genes; C3HDZs) spanning lycophytes and ferns. We show that a duplication and neofunctionalization of C3HDZs probably occurred in the ancestor of euphyllophytes, and that there is a common leaf developmental mechanism conserved between ferns and seed plants. We show C3HDZ expression in lycophyte and fern sporangia and show that C3HDZs have conserved expression patterns during initiation of lateral primordia (leaves or sporangia). This expression is maintained throughout sporangium development in lycophytes and ferns and indicates an ancestral role of C3HDZs in sporangium development. We hypothesize that there is a deep homology of all leaves and that a sporangium-specific developmental program was coopted independently for the development of lycophyte and euphyllophyte leaves. This provides molecular genetic support for a paradigm shift in theories of lycophyte leaf evolution.

  3. Biochemical characterization of a recombinant plant class III chitinase from the pitcher of the carnivorous plant Nepenthes alata.

    PubMed

    Ishisaki, Kana; Arai, Sachiko; Hamada, Tatsuro; Honda, Yuji

    2012-11-01

    A class III chitinase belonging to the GH18 family from Nepenthes alata (NaCHIT3) was expressed in Escherichia coli. The enzyme exhibited hydrolytic activity toward colloidal chitin, ethylene glycol chitin, and (GlcNAc)(n) (n=5 and 6). The enzyme hydrolyzed the fourth glycosidic linkage from the non-reducing end of (GlcNAc)(6). The anomeric form of the products indicated it was a retaining enzyme. The colloidal chitin hydrolytic reaction displayed high activity between pH 3.9 and 6.9, but the pH optimum of the (GlcNAc)(6) hydrolytic reaction was 3.9 at 37 °C. The optimal temperature for activity was 65 °C in 50 mM sodium acetate buffer (pH 3.9). The pH optima of NaCHIT3 and NaCHIT1 might be related to their roles in chitin degradation in the pitcher fluid.

  4. Biochemical analysis of callus tissue in osteogenesis imperfecta type IV. Evidence for transient overmodification in collagen types I and III.

    PubMed Central

    Brenner, R E; Vetter, U; Nerlich, A; Wörsdorfer, O; Teller, W M; Müller, P K

    1989-01-01

    We analyzed tissue and cells from a stationary and a rapidly growing hyperplastic callus from a patient with osteogenesis imperfecta (OI) type IV and compared the results with those of compact bone and skin fibroblasts of an age-matched control. Collagen and protein contents per cell were low in the callus tissues and collagen I and III were overmodified as evidenced by an elevated level of hydroxylysine. The degree of lysyl hydroxylation was highest in those regions that appeared most immature by histological examination. Lysyl hydroxylation approached normal levels in collagen from the stationary callus and from the center of the growing callus. Overmodification of collagen was not seen in compact bone or cell cultures (neither skin fibroblasts nor callus cells) from the patient. Elevation of hydroxylysine in collagen from OI patients is generally attributed to mutations that delay triple helix formation. Our observations suggest that the varying degree of collagen modifications may occur in consequence of regulatory mechanisms during bone development and tissue repair. These mechanisms may be defective in some patients with OI as seen in this case with hyperplastic callus formation. Images PMID:2760218

  5. Effects of combined dietary chromium(III) propionate complex and thiamine supplementation on insulin sensitivity, blood biochemical indices, and mineral levels in high-fructose-fed rats.

    PubMed

    Król, Ewelina; Krejpcio, Zbigniew; Michalak, Sławomir; Wójciak, Rafał W; Bogdański, Paweł

    2012-12-01

    Insulin resistance is the first step in glucose intolerance and the development of type 2 diabetes mellitus, thus effective prevention strategies should also include dietary interventions to enhance insulin sensitivity. Nutrients, such as microelement chromium(III) and thiamine, play regulatory roles in carbohydrate metabolism. The objective of this study was to evaluate the insulin-sensitizing potential of the combined supplementary chromium(III) propionate complex (CrProp) and thiamine in insulin resistance animal model (rats fed a high-fructose diet). The experiment was carried out on 40 nine-week-old male Wistar rats divided into five groups (eight animals each). Animals were fed ad libitum: the control diet (AIN-93 M) and high-fructose diets with and without a combination of two levels of CrProp (0.1 and 1 mg Cr/kg body mass/day) and two levels of thiamine (0.5 and 10 mg/kg body mass/day) for 8 weeks. At the end of the experiment rats were sacrificed to collect blood and internal organs for analyses of blood biochemical and hematologic indices as well as tissular microelement levels that were measured using appropriate methods. It was found that both supplementary CrProp and thiamine (given alone) have significant insulin-sensitizing and moderate blood-lipid-lowering properties, while the combined supplementation with these agents does not give synergistic effects in insulin-resistant rats. CrProp given separately increased kidney Cu and Cr levels, while thiamine alone increased hepatic Cu contents and decreased renal Zn and Cu contents.

  6. The Assembly and Evolution of Eastern Laurentia: Evidence from the QM-III Experiment

    NASA Astrophysics Data System (ADS)

    Darbyshire, F. A.; Levin, V. L.; Menke, W. H.; Bastow, I. D.; Petrescu, L.; Boyce, A.; Klaser, M.; Dunham, B.; Servali, A.; Neitz, T.

    2014-12-01

    Eastern North America is an excellent region to test hypotheses about the evolution through time of tectonic processes, the growth of continental crust and the assembly of continents. Over a spatial scale of just a few hundred kilometres, the surface geology records almost 3 billion years of Earth history, with a transition from the Archean Superior craton through the Proterozoic Grenville orogenic belt to the Phanerozoic Appalachian terranes and the edge of the North American continent. The boundaries between these major tectonic provinces have been mapped at the surface, and crustal-scale geophysical studies (e.g. LITHOPROBE) have been able to trace their complex signatures to the Moho and below in some parts of eastern Canada. Nevertheless, the nature of the boundaries across the region, and their continuation into the lithospheric mantle, remains enigmatic. The high wavespeed lithospheric keel of the Canadian Shield extends beneath the Proterozoic terranes; however it is still unclear whether this material represents a continuation of Archean lithosphere over which the Grenville terranes have been thrust, or whether the Grenville can be associated with its own thick keel. The transition from Proterozoic to Phanerozoic lithosphere beneath the Appalachian Front is likewise ambiguous. To shed new light on the tectonic evolution of the region, and the nature of the major tectonic boundaries, a broadband seismograph network was installed in eastern Canada in 2012-2013 through the QM-III (Quebec-Maine Across Three Sutures) experiment; stations will remain in place for 2-3 years. The network consists of a dense NW-SE profile from the southern tip of Hudson Bay to coastal Maine, supplemented by existing more sparsely-distributed stations, and a 2D deployment across Maritime Canada. Data acquisition is ongoing, but preliminary results from receiver function analysis, travel-time tomography and surface-wave dispersion are already showing some intriguing variations in

  7. EVOLUTION OF VERY MASSIVE POPULATION III STARS WITH MASS ACCRETION FROM PRE-MAIN SEQUENCE TO COLLAPSE

    SciTech Connect

    Ohkubo, Takuya; Nomoto, Ken'ichi; Umeda, Hideyuki; Yoshida, Naoki; Tsuruta, Sachiko E-mail: umeda@astron.s.u-tokyo.ac.j E-mail: naoki.yoshida@ipmu.j

    2009-12-01

    We calculate the evolution of zero-metallicity Population III (Pop III) stars whose mass grows from the initial mass of approx1 M{sub sun} by accreting the surrounding gases. Our calculations cover whole evolutionary stages from the pre-main sequence, via various nuclear burning stages, through the final core-collapse or pair-creation instability phases. We adopt two different sets of stellar mass accretion rates as our fiducial models. One is derived from a cosmological simulation of the first generation (PopIII.1) stars, and the other is derived from a simulation of the second generation stars that are affected by radiation from PopIII.1 stars. The latter represents one case of PopIII.2 stars. We also adopt additional models that include radiative feedback effects. We show that the final mass of Pop III.1 stars can be as large as approx1000 M {sub sun}, beyond the mass range (140-300 M{sub sun}) for the pair-instability supernovae. Such massive stars undergo core-collapse to form intermediate-mass black holes, which may be the seeds for merger trees to supermassive black holes. On the other hand, Pop III.2 stars become less massive (approx<40-60 M{sub sun}), being in the mass range of ordinary iron core-collapse stars. Such stars explode and eject heavy elements to contribute to chemical enrichment of the early universe as observed in the abundance patterns of extremely metal-poor stars in the Galactic halo. In view of the large range of possible accretion rates, further studies are important to see if these fiducial models are actually the cases.

  8. Adaptation of a cyanobacterium to a biochemically rich environment in experimental evolution as an initial step toward a chloroplast-like state.

    PubMed

    Hosoda, Kazufumi; Habuchi, Masumi; Suzuki, Shingo; Miyazaki, Mikako; Takikawa, Go; Sakurai, Takahiro; Kashiwagi, Akiko; Sueyoshi, Makoto; Matsumoto, Yusuke; Kiuchi, Ayako; Mori, Kotaro; Yomo, Tetsuya

    2014-01-01

    Chloroplasts originated from cyanobacteria through endosymbiosis. The original cyanobacterial endosymbiont evolved to adapt to the biochemically rich intracellular environment of the host cell while maintaining its photosynthetic function; however, no such process has been experimentally demonstrated. Here, we show the adaptation of a model cyanobacterium, Synechocystis sp. PCC 6803, to a biochemically rich environment by experimental evolution. Synechocystis sp. PCC 6803 does not grow in a biochemically rich, chemically defined medium because several amino acids are toxic to the cells at approximately 1 mM. We cultured the cyanobacteria in media with the toxic amino acids at 0.1 mM, then serially transferred the culture, gradually increasing the concentration of the toxic amino acids. The cells evolved to show approximately the same specific growth rate in media with 0 and 1 mM of the toxic amino acid in approximately 84 generations and evolved to grow faster in the media with 1 mM than in the media with 0 mM in approximately 181 generations. We did not detect a statistically significant decrease in the autotrophic growth of the evolved strain in an inorganic medium, indicating the maintenance of the photosynthetic function. Whole-genome resequencing revealed changes in the genes related to the cell membrane and the carboxysome. Moreover, we quantitatively analyzed the evolutionary changes by using simple mathematical models, which evaluated the evolution as an increase in the half-maximal inhibitory concentration (IC50) and estimated quantitative characteristics of the evolutionary process. Our results clearly demonstrate not only the potential of a model cyanobacterium to adapt to a biochemically rich environment without a significant decrease in photosynthetic function but also the properties of its evolutionary process, which sheds light of the evolution of chloroplasts at the initial stage.

  9. A prescription and fast code for the long-term evolution of star clusters - III. Unequal masses and stellar evolution

    NASA Astrophysics Data System (ADS)

    Alexander, Poul E. R.; Gieles, Mark; Lamers, Henny J. G. L. M.; Baumgardt, Holger

    2014-08-01

    We present a new version of the fast star cluster evolution code EVOLVE ME A CLUSTER OF STARS (EMACSS). While previous versions of EMACSS reproduced clusters of single-mass stars, this version models clusters with an evolving stellar content. Stellar evolution dominates early evolution, and leads to: (1) reduction of the mean mass of stars due to the mass loss of high-mass stars; (2) expansion of the half-mass radius; (3) for (nearly) Roche Volume filling clusters, the induced escape of stars. Once sufficient relaxation has occurred (≃10 relaxation times-scales), clusters reach a second, `balanced' state whereby the core releases energy as required by the cluster as a whole. In this state: (1) stars escape due to tidal effects faster than before balanced evolution; (2) the half-mass radius expands or contracts depending on the Roche volume filling factor; and (3) the mean mass of stars increases due to the preferential ejection of low-mass stars. We compare the EMACSS results of several cluster properties against N-body simulations of clusters spanning a range of initial number of stars, mass, half-mass radius, and tidal environments, and show that our prescription accurately predicts cluster evolution for this data base. Finally, we consider applications for EMACSS, such as studies of galactic globular cluster populations in cosmological simulations.

  10. Evolution of corundum-structured III-oxide semiconductors: Growth, properties, and devices

    NASA Astrophysics Data System (ADS)

    Fujita, Shizuo; Oda, Masaya; Kaneko, Kentaro; Hitora, Toshimi

    2016-12-01

    The recent progress and development of corundum-structured III-oxide semiconductors are reviewed. They allow bandgap engineering from 3.7 to ∼9 eV and function engineering, leading to highly durable electronic devices and deep ultraviolet optical devices as well as multifunctional devices. Mist chemical vapor deposition can be a simple and safe growth technology and is advantageous for reducing energy and cost for the growth. This is favorable for the wide commercial use of devices at low cost. The III-oxide semiconductors are promising candidates for new devices contributing to sustainable social, economic, and technological development for the future.

  11. Structure, Evolution, and Functions of Bacterial Type III Toxin-Antitoxin Systems

    PubMed Central

    Goeders, Nathalie; Chai, Ray; Chen, Bihe; Day, Andrew; Salmond, George P. C.

    2016-01-01

    Toxin-antitoxin (TA) systems are small genetic modules that encode a toxin (that targets an essential cellular process) and an antitoxin that neutralises or suppresses the deleterious effect of the toxin. Based on the molecular nature of the toxin and antitoxin components, TA systems are categorised into different types. Type III TA systems, the focus of this review, are composed of a toxic endoribonuclease neutralised by a non-coding RNA antitoxin in a pseudoknotted configuration. Bioinformatic analysis shows that the Type III systems can be classified into subtypes. These TA systems were originally discovered through a phage resistance phenotype arising due to a process akin to an altruistic suicide; the phenomenon of abortive infection. Some Type III TA systems are bifunctional and can stabilise plasmids during vegetative growth and sporulation. Features particular to Type III systems are explored here, emphasising some of the characteristics of the RNA antitoxin and how these may affect the co-evolutionary relationship between toxins and cognate antitoxins in their quaternary structures. Finally, an updated analysis of the distribution and diversity of these systems are presented and discussed. PMID:27690100

  12. Analysis of conifer FLOWERING LOCUS T/TERMINAL FLOWER1-like genes provides evidence for dramatic biochemical evolution in the angiosperm FT lineage.

    PubMed

    Klintenäs, Maria; Pin, Pierre A; Benlloch, Reyes; Ingvarsson, Pär K; Nilsson, Ove

    2012-12-01

    In flowering plants, homologs of the Arabidopsis phosphatidylethanolamine-binding protein (PEBP) FLOWERING LOCUS T (FT) are key components in controlling flowering time. We show here that, although FT homologs are found in all angiosperms with completed genome sequences, there is no evidence to date that FT-like genes exist in other groups of plants. Through phylogeny reconstructions and heterologous expression, we examined the biochemical function of the Picea (spruces) and Pinus (pines) PEBP families - two gymnosperm taxa phylogenetically distant from the angiosperms. We have defined a lineage of gymnosperm PEBP genes, termed the FT/TERMINAL FLOWER1 (TFL1)-like genes, that share sequence characteristics with both the angiosperm FT- and TFL1-like clades. When expressed in Arabidopsis, FT/TFL1-like genes repressed flowering, indicating that the proteins are biochemically more similar to the angiosperm TFL1-like proteins than to the FT-like proteins. This suggests that the regulation of the vegetative-to-reproductive switch might differ in gymnosperms compared with angiosperms. Molecular evolution studies suggest that plasticity at exon 4 contributes to the divergence of FT-like function in floral promotion. In addition, the presence of FT-like genes in basal angiosperms indicates that the FT-like function emerged at an early stage during the evolution of flowering plants as a means to regulate flowering time.

  13. The effects of stimulated star formation on the evolution of the galaxy. III - The chemical evolution of nonlinear systems

    NASA Technical Reports Server (NTRS)

    Shore, Steven N.; Ferrini, Federico; Palla, Francesco

    1987-01-01

    The evolution of models for star formation in galaxies with disk and halo components is discussed. Two phases for the halo (gas and stars) and three for the disk (including clouds) are used in these calculations. The star-formation history is followed using nonlinear phase-coupling models which completely determine the populations of the phases as a function of time. It is shown that for a wide range of parameters, including the effects of both spontaneous and stimulated star formation and mass exchange between the spatial components of the system, the observed chemical history of the galaxy can easily be obtained. The most sensitive parameter in the detailed metallicity and star-formation history for the system is the rate of return of gas to the diffuse phase upon stellar death.

  14. Diversifying selection drives the evolution of the type III secretion system pilus of Pseudomonas syringae.

    PubMed

    Guttman, David S; Gropp, Susan J; Morgan, Robyn L; Wang, Pauline W

    2006-12-01

    The plant pathogenic bacterium Pseudomonas syringae uses a type III secretion system to inject virulence proteins directly into the cytoplasm of its hosts. The P. syringae type III secretion apparatus is encoded, in part, by the HrpZ operon, which carries the hrpA gene encoding the pilin subunit of the pilus, various components of the structural apparatus, and the HrpZ harpin protein that is believed to produce pores in the host cell membrane. The pilus of the type III system comes into direct contact with the host cell and is, therefore, a likely target of the host's pathogen surveillance systems. We sequenced and analyzed 22 HrpZ operons from P. syringae strains spanning the diversity of the species. Selection analyses, including K(a)/K(s) tests and Tajima's D, revealed strong diversifying selection acting on the hrpA gene. This form of selection enables pathogens to maintain genetic diversity within their populations and is often driven by selection imposed by host defense systems. The HrpZ operon also revealed a single significant recombination event that dramatically changed the evolutionary relationships among P. syringae strains from 2 quite distinct phylogroups. This recombination event appears to have introduced genetic diversity into a clade of strains that may now be undergoing positive selection. The identification of diversifying selection acting on the Hrp pilus across the whole population sample and positive selection within one P. syringae lineage supports a trench warfare coevolutionary model between P. syringae and its plant hosts.

  15. Acoustic Microsensors III. Direct Detection of Staphylococcal Enterotoxin B Employing a Piezoelectric Crystal Immunosensor with a Flexible Carboxylated Dextran Matrix as the Biochemical Interface.

    DTIC Science & Technology

    1998-03-01

    of the hydrogel matrix are: • an increased immobilization capacity as compared to monolayer based coat- ings: the dextran layer is about 100 nm...employing a piezoelectric crystal immunosensor with a flexible carboxylated dextran matrix as the biochemical interface Lange Kleiweg 137 P.O. Box 45... dextran matrix as the biochemical in- terface Auteur(s) J.L.N. Harteveld Datum maart 1998 Opdrachtnr. : A93KL448 Rapportnr. : PML 1997-A58

  16. Rotation in the Pleiades with K2. III. Speculations on Origins and Evolution

    NASA Astrophysics Data System (ADS)

    Stauffer, John; Rebull, Luisa; Bouvier, Jerome; Hillenbrand, Lynne A.; Collier-Cameron, Andrew; Pinsonneault, Marc; Aigrain, Suzanne; Barrado, David; Bouy, Herve; Ciardi, David; Cody, Ann Marie; David, Trevor; Micela, Giusi; Soderblom, David; Somers, Garrett; Stassun, Keivan G.; Valenti, Jeff; Vrba, Frederick J.

    2016-11-01

    We use high-quality K2 light curves for hundreds of stars in the Pleiades to better understand the angular momentum evolution and magnetic dynamos of young low-mass stars. The K2 light curves provide not only rotational periods but also detailed information from the shape of the phased light curve that was not available in previous studies. A slowly rotating sequence begins at {(V-{K}{{s}})}0 ˜ 1.1 (spectral type F5) and ends at {(V-{K}{{s}})}0 ˜ 3.7 (spectral type K8), with periods rising from ˜2 to ˜11 days in that interval. A total of 52% of the Pleiades members in that color interval have periods within 30% of a curve defining the slow sequence; the slowly rotating fraction decreases significantly redward of {(V-{K}{{s}})}0 = 2.6. Nearly all of the slow-sequence stars show light curves that evolve significantly on timescales less than the K2 campaign duration. The majority of the FGK Pleiades members identified as photometric binaries are relatively rapidly rotating, perhaps because binarity inhibits star-disk angular momentum loss mechanisms during pre-main-sequence evolution. The fully convective late M dwarf Pleiades members (5.0 < {(V-{K}{{s}})}0 < 6.0) nearly always show stable light curves, with little spot evolution or evidence of differential rotation. During pre-main-sequence evolution from ˜3 Myr (NGC 2264 age) to ˜125 Myr (Pleiades age), stars of 0.3 {M}⊙ shed about half of their angular momentum, with the fractional change in period between 3 and 125 Myr being nearly independent of mass for fully convective stars. Our data also suggest that very low mass binaries form with rotation periods more similar to each other and faster than would be true if drawn at random from the parent population of single stars.

  17. Enthalpy-Based Thermal Evolution of Loops: III. Comparison of Zero-Dimensional Models

    NASA Technical Reports Server (NTRS)

    Cargill, P. J.; Bradshaw, Stephen J.; Klimchuk, James A.

    2012-01-01

    Zero dimensional (0D) hydrodynamic models, provide a simple and quick way to study the thermal evolution of coronal loops subjected to time-dependent heating. This paper presents a comparison of a number of 0D models that have been published in the past and is intended to provide a guide for those interested in either using the old models or developing new ones. The principal difference between the models is the way the exchange of mass and energy between corona, transition region and chromosphere is treated, as plasma cycles into and out of a loop during a heating-cooling cycle. It is shown that models based on the principles of mass and energy conservation can give satisfactory results at some, or, in the case of the Enthalpy Based Thermal Evolution of Loops (EBTEL) model, all stages of the loop evolution. Empirical models can lead to low coronal densities, spurious delays between the peak density and temperature, and, for short heating pulses, overly short loop lifetimes.

  18. ENTHALPY-BASED THERMAL EVOLUTION OF LOOPS. III. COMPARISON OF ZERO-DIMENSIONAL MODELS

    SciTech Connect

    Cargill, P. J.; Bradshaw, S. J.; Klimchuk, J. A.

    2012-10-10

    Zero-dimensional (0D) hydrodynamic models provide a simple and quick way to study the thermal evolution of coronal loops subjected to time-dependent heating. This paper presents a comparison of a number of 0D models that have been published in the past and is intended to provide a guide for those interested in either using the old models or developing new ones. The principal difference between the models is the way the exchange of mass and energy between corona, transition region, and chromosphere is treated, as plasma cycles into and out of a loop during a heating-cooling cycle. It is shown that models based on the principles of mass and energy conservation can give satisfactory results at some or, in the case of the Enthalpy-based Thermal Evolution of Loops model, all stages of the loop evolution. Empirical models can have significant difficulties in obtaining accurate behavior due to invocation of assumptions incompatible with the correct exchange of mass and energy between corona, transition region, and chromosphere.

  19. The evolution of the EGFRvIII (rindopepimut) immunotherapy for glioblastoma multiforme patients

    PubMed Central

    Paff, Michelle; Alexandru-Abrams, Daniela; Hsu, Frank P K; Bota, Daniela A

    2015-01-01

    Glioblastoma Multiforme (GBM) is the most common type of brain tumor and it is uniformly fatal. The community standard of treatment for this disease is gross or subtotal resection of the tumor, followed by radiation and temozolomide. At recurrence bevacizumab can be added for increased progression free survival. Many challenges are encountered while trying to devise new drugs to treat GBM, such as the presence of the blood brain barrier which is impermeable to most drugs. Therefore in the past few years attention was turned to immunological means for the treatment of this devastating disease. EGFRvIII targeting has proven a good way to attack glioblastoma cells by using the immune system. Although in still in development, this approach holds the promise as a great first step toward immune-tailored drugs for the treatment of brain cancers. PMID:25625931

  20. Charge state evolution in the solar wind. III. Model comparison with observations

    SciTech Connect

    Landi, E.; Oran, R.; Lepri, S. T.; Zurbuchen, T. H.; Fisk, L. A.; Van der Holst, B.

    2014-08-01

    We test three theoretical models of the fast solar wind with a set of remote sensing observations and in-situ measurements taken during the minimum of solar cycle 23. First, the model electron density and temperature are compared to SOHO/SUMER spectroscopic measurements. Second, the model electron density, temperature, and wind speed are used to predict the charge state evolution of the wind plasma from the source regions to the freeze-in point. Frozen-in charge states are compared with Ulysses/SWICS measurements at 1 AU, while charge states close to the Sun are combined with the CHIANTI spectral code to calculate the intensities of selected spectral lines, to be compared with SOHO/SUMER observations in the north polar coronal hole. We find that none of the theoretical models are able to completely reproduce all observations; namely, all of them underestimate the charge state distribution of the solar wind everywhere, although the levels of disagreement vary from model to model. We discuss possible causes of the disagreement, namely, uncertainties in the calculation of the charge state evolution and of line intensities, in the atomic data, and in the assumptions on the wind plasma conditions. Last, we discuss the scenario where the wind is accelerated from a region located in the solar corona rather than in the chromosphere as assumed in the three theoretical models, and find that a wind originating from the corona is in much closer agreement with observations.

  1. The evolution of clinical gait analysis part III--kinetics and energy assessment.

    PubMed

    Sutherland, D H

    2005-06-01

    Historically, clinical applications of measurements of force and energy followed electromyography and kinematics in temporal sequence. This sequence is mirrored by the order of topics included in this trilogy on the Evolution of Clinical Gait Analysis, with part I [Sutherland DH. The evolution of clinical gait analysis part I: kinesiological EMG. Gait Posture 2001;14:61-70.] devoted to Kinesiological EMG and part II [Sutherland DH. The evolution of clinical gait analysis part II - kinematics. Gait Posture 2002;16(2):159-179.] to Kinematics. This final review in the series will focus on kinetics as it relates to gait applications. Kinematic measurements give the movements of the body segments, which can be compared with normal controls to identify pathological gait patterns, but they do not deal with the forces controlling the movements. As a major goal of scientifically minded clinicians is to understand the biomechanical forces producing movements, the objective measurement of ground reaction forces is essential. The force plate (platform) is now an indispensable tool in a state-of-the-art motion analysis laboratory. Nonetheless, it is not a stand-alone instrument as both kinematic and EMG measurements are needed for maximum clinical implementation and interpretation of force plate measurements. The subject of energy assessment is also given mention, as there is a compelling interest in whether walking has been made easier with intervention. The goals of this manuscript are to provide a historical background, recognize some of the important contributors, and describe the current multiple uses of the force plate in gait analysis. The widespread use of force plates for postural analyses is an important and more recent application of this technology, but this review will be restricted to measurements of gait rather than balance activities. Finally, this manuscript presents my personal perspective and discusses the developments and contributors that have shaped my

  2. On the evolution of epistasis III: the haploid case with mutation.

    PubMed

    Liberman, Uri; Feldman, Marcus

    2008-03-01

    Whether interaction between genes is better represented by synergistic or antagonistic epistasis has been a focus of experimental research in bacterial population genetics. Our previous research on evolution of modifiers of epistasis in diploid systems has indicated that the strength of positive or negative epistasis should increase provided linkage disequilibrium is maintained. Here we study a modifier of epistasis in fitness between two loci in a haploid system. Epistasis is modified in the neighborhood of a mutation-selection balance. We show that when linkage in the three-locus system is tight, an increase in the frequency of a modifier allele that induces either more negative or more positive epistasis is possible. Epistasis here can be measured on either an additive or multiplicative scale.

  3. Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). III. Karyotype relationships of ten Microtus species.

    PubMed

    Lemskaya, Natalia A; Romanenko, Svetlana A; Golenishchev, Feodor N; Rubtsova, Nadezhda V; Sablina, Olga V; Serdukova, Natalya A; O'Brien, Patricia C M; Fu, Beiyuan; Yiğit, Nuri; Ferguson-Smith, Malcolm A; Yang, Fengtang; Graphodatsky, Alexander S

    2010-06-01

    The genus Microtus consists of 65 extant species, making it one of the rodentia genera with the highest number of species. The extreme karyotype diversification in Microtus has made them an ideal species group for comparative cytogenetics and cytotaxonomy. Conventional comparative cytogenetic studies in Microtus have been based mainly on chromosomal banding patterns; the number of Microtus species examined by molecular cytogenetics-cross-species chromosome painting-is limited. In this study, we used whole chromosome painting probes of the field vole Microtus agrestis to detect regions of homology in the karyotypes of eight Microtus species. For almost all investigated species, species-specific associations of conserved chromosomal segments were revealed. Analysis of data obtained here and previously published data allowed us to propose that the ancestral Microtus species had a 2n = 54 karyotype, including two associations of field vole chromosomal segments (MAG 1/17 and 2/8). Further mapping of the chromosome rearrangements onto a molecular phylogenetic tree allows the reconstruction of a karyotype evolution pathway in the Microtus genus.

  4. Galaxy Assembly and the Evolution of Structure over the First Third of Cosmic Time - III

    NASA Astrophysics Data System (ADS)

    Faber, Sandra

    2011-10-01

    This survey will document the first third of galactic evolution fromz=8 to 1.5 andtest for evolution in the properties of Type Ia supernovae to z 2 byimaging more than 250,000 galaxies with WFC3/IR and ACS. Five premiermulti-wavelength regions are selected from within the Spitzer SEDSsurvey, providing complementaryIRAC data down to 26.5 AB mag, a unique resource forstellar masses at high redshifts. The use of five widely separatedfields mitigates cosmic variance and yields statistically robustsamples of galaxies down to 10^9 M_Sun out to z 8.We adopt a two-tiered strategy with a "Wide" component {roughly 2orbits deep over 0.2 sq. degrees} and a "Deep" component {roughly 12orbits deep over 0.04 sq. degrees}. Combining these with ultra-deepimaging from the Cycle 17 HUDF09 program yields a three-tieredstrategy for efficient sampling of both rare/bright and faint/commonobjects.Three of the Wide-survey fields are located in COSMOS, EGS, andUKIDSS/UDS. Each of these consists of roughly 3x15 WFC3/IR tiles.Each WFC3 tile will be observed for 2 orbits, with single orbitsseparated in time to allow a search for high-redshift Type Ia SNe.The co-added exposure times will be approximately 2/3 orbit in J{F125W} and 4/3 orbit in H {F160W}. ACS parallels overlap most of theWFC3 area and will consist of roughly 2/3 orbits in V {F606W} and4/3 orbit in I {F814W}. Because of the larger area of ACS,this results in effective exposures that are twice as long {4/3 in V,8/3 in I}, making a very significant improvement to existing ACSmosaics in COSMOS and EGS and creating a new ACS mosaic in UDS/UKIDSSwhere none now exists. Other Wide-survey components are located inthe GOODS fields {North and South} surrounding the Deep-survey areas.The Deep-survey fields cover roughly half of each GOODS field, withexact areas and placements to be determined as part of the Phase-2process. Each WFC3/IR tile within the Deep regions will receiveapproximately 12 orbits of exposure time split between Y{F105W}, J

  5. Evolution of planetary nebulae. III. Position-velocity images of butterfly-type nebulae

    SciTech Connect

    Icke, V.; Preston, H.L.; Balick, B.

    1989-02-01

    Observations of the motions of the shells of the planetary nebulae NGC 2346, NGC 2371-2, NGC 2440, NGC 6058, NGC 6210, IC 1747, IC 5217, J-320, and M2-9 are presented. These are all 'butterfly' type PNs, and show evidence for bipolar shocks. The observations are interpreted in terms of a fast spherical wind, driven by the central star into a quasi-toroidal envelope deposited earlier by the star, during its slow-wind phase on the asymptotic giant branch. It is shown that this model, which is a straightforward extension of a mechanism previously invoked to account for elliptical PNs, reproduces the essential kinematic features of butterfly PNs. It is inferred that the envelopes of butterflies must have a considerable equator-to-pole density gradient, and it is suggested that the origin of this asphericity must be sought in an as yet unknown mechanism during the AGB, Mira, or OH/IR phases of late stellar evolution. 28 references.

  6. Oxygen and hydrogen peroxide in the early evolution of life on earth: in silico comparative analysis of biochemical pathways.

    PubMed

    Slesak, Ireneusz; Slesak, Halina; Kruk, Jerzy

    2012-08-01

    In the Universe, oxygen is the third most widespread element, while on Earth it is the most abundant one. Moreover, oxygen is a major constituent of all biopolymers fundamental to living organisms. Besides O(2), reactive oxygen species (ROS), among them hydrogen peroxide (H(2)O(2)), are also important reactants in the present aerobic metabolism. According to a widely accepted hypothesis, aerobic metabolism and many other reactions/pathways involving O(2) appeared after the evolution of oxygenic photosynthesis. In this study, the hypothesis was formulated that the Last Universal Common Ancestor (LUCA) was at least able to tolerate O(2) and detoxify ROS in a primordial environment. A comparative analysis was carried out of a number of the O(2)-and H(2)O(2)-involving metabolic reactions that occur in strict anaerobes, facultative anaerobes, and aerobes. The results indicate that the most likely LUCA possessed O(2)-and H(2)O(2)-involving pathways, mainly reactions to remove ROS, and had, at least in part, the components of aerobic respiration. Based on this, the presence of a low, but significant, quantity of H(2)O(2) and O(2) should be taken into account in theoretical models of the early Archean atmosphere and oceans and the evolution of life. It is suggested that the early metabolism involving O(2)/H(2)O(2) was a key adaptation of LUCA to already existing weakly oxic zones in Earth's primordial environment.

  7. MOLECULAR EVOLUTION OF GLUTAMINE SYNTHETASE II AND III IN THE CHROMALVEOLATES(1).

    PubMed

    Ghoshroy, Sohini; Robertson, Deborah L

    2012-06-01

    Glutamine synthetase (GS) is encoded by three distinct gene families (GSI, GSII, and GSIII) that are broadly distributed among the three domains of life. Previous studies established that GSII and GSIII isoenzymes were expressed in diatoms; however, less is known about the distribution and evolution of the gene families in other chromalveolate lineages. Thus, GSII cDNA sequences were isolated from three cryptophytes (Guillardia theta D. R. A. Hill et Wetherbee, Cryptomonas phaseolus Skuja, and Pyrenomonas helgolandii Santore), and GSIII was sequenced from G. theta. Red algal GSII sequences were obtained from Bangia atropurpurea (Mertens ex Roth) C. Agardh; Compsopogon caeruleus (Balbis ex C. Agardh) Mont.; Flintiella sanguinaria F. D. Ott and Porphyridium aerugineum Geitler; Rhodella violacea (Kornmann) Wehrmeyer and Dixoniella grisea (Geitler) J. L. Scott, S. T. Broadwater, B. D. Saunders, J. P. Thomas et P. W. Gabrielson; and Stylonema alsidii (Zanardini) K. M. Drew. In Bayesian inference and maximum-likelihood (ML) phylogenetic analyses, chromalveolate GSII sequences formed a weakly supported clade that nested among sequences from glaucophytes, red algae, green algae, and plants. Red algal GSII sequences formed two distinct clades. The largest clade contained representatives from the Cyanidiophytina and Rhodophytina and grouped with plants and green algae. The smaller clade (C. caeruleus, Porphyra yezoensis, and S. alsidii) nested within the chromalveolates, although its placement was unresolved. Chromalveolate GSIII sequences formed a well-supported clade in Bayesian and ML phylogenies, and mitochondrial transit peptides were identified in many of the sequences. There was strong support for a stramenopile-haptophyte-cryptophyte GSIII clade in which the cryptophyte sequence diverged from the deepest node. Overall, the evolutionary history of the GS gene families within the algae is complex with evidence for the presence of orthologous and paralogous sequences

  8. The nature of Hβ+[O III] and [O II] emitters to z ˜ 5 with HiZELS: stellar mass functions and the evolution of EWs

    NASA Astrophysics Data System (ADS)

    Khostovan, A. A.; Sobral, D.; Mobasher, B.; Smail, I.; Darvish, B.; Nayyeri, H.; Hemmati, S.; Stott, J. P.

    2016-12-01

    We investigate the properties of ˜7000 narrow-band selected galaxies with strong Hβ+[O III] and [O II] nebular emission lines from the High-z Emission-Line Survey between z ˜ 0.8 and 5.0. Our sample covers a wide range in stellar mass (Mstellar ˜ 107.5-12.0 M⊙), rest-frame equivalent widths (EWrest˜10-105 Å), and line luminosities (Lline ˜ 1040.5-43.2 erg s-1). We measure the Hβ+[O III]-selected stellar mass functions out to z ˜ 3.5 and find that both M⋆ and φ⋆ increases with cosmic time. The [O II]-selected stellar mass functions show a constant M⋆ ≈ 1011.6 M⊙ and a strong, increasing evolution with cosmic time in φ⋆ in line with Hα studies. We also investigate the evolution of the EWrest as a function of redshift with a fixed mass range (109.5-10.0 M⊙) and find an increasing trend best represented by (1 + z)3.81 ± 0.14 and (1 + z)2.72 ± 0.19 up to z ˜ 2 and ˜3 for Hβ+[O III] and [O II] emitters, respectively. This is the first time that the EWrest evolution has been directly measured for Hβ+[O III] and [O II] emitters up to these redshifts. There is evidence for a slower evolution for z > 2 in the Hβ+[O III] EWrest and a decreasing trend for z > 3 in the [O II] EWrest evolution, which would imply low [O II] EW at the highest redshifts and higher [O III]/[O II] line ratios. This suggests that the ionization parameter at higher redshift may be significantly higher than the local Universe. Our results set the stage for future near-IR space-based spectroscopic surveys to test our extrapolated predictions and also produce z > 5 measurements to constrain the high-z end of the EWrest and [O III]/[O II] evolution.

  9. Oxygen and Hydrogen Peroxide in the Early Evolution of Life on Earth: In silico Comparative Analysis of Biochemical Pathways

    PubMed Central

    Ślesak, Halina; Kruk, Jerzy

    2012-01-01

    Abstract In the Universe, oxygen is the third most widespread element, while on Earth it is the most abundant one. Moreover, oxygen is a major constituent of all biopolymers fundamental to living organisms. Besides O2, reactive oxygen species (ROS), among them hydrogen peroxide (H2O2), are also important reactants in the present aerobic metabolism. According to a widely accepted hypothesis, aerobic metabolism and many other reactions/pathways involving O2 appeared after the evolution of oxygenic photosynthesis. In this study, the hypothesis was formulated that the Last Universal Common Ancestor (LUCA) was at least able to tolerate O2 and detoxify ROS in a primordial environment. A comparative analysis was carried out of a number of the O2-and H2O2-involving metabolic reactions that occur in strict anaerobes, facultative anaerobes, and aerobes. The results indicate that the most likely LUCA possessed O2-and H2O2-involving pathways, mainly reactions to remove ROS, and had, at least in part, the components of aerobic respiration. Based on this, the presence of a low, but significant, quantity of H2O2 and O2 should be taken into account in theoretical models of the early Archean atmosphere and oceans and the evolution of life. It is suggested that the early metabolism involving O2/H2O2 was a key adaptation of LUCA to already existing weakly oxic zones in Earth's primordial environment. Key Words: Hydrogen peroxide—Oxygen—Origin of life—Photosynthesis—Superoxide dismutase—Superoxide reductase. Astrobiology 12, 775–784. PMID:22970865

  10. POISSON project. III. Investigating the evolution of the mass accretion rate

    NASA Astrophysics Data System (ADS)

    Antoniucci, S.; García López, R.; Nisini, B.; Caratti o Garatti, A.; Giannini, T.; Lorenzetti, D.

    2014-12-01

    Context. As part of the Protostellar Optical-Infrared Spectral Survey On NTT (POISSON) project, we present the results of the analysis of low-resolution near-IR spectroscopic data (0.9-2.4 μm) of two samples of young stellar objects in the Lupus (52 objects) and Serpens (17 objects) star-forming clouds, with masses in the range of 0.1 to 2.0 M⊙ and ages spanning from 105 to a few 107 yr. Aims: After determining the accretion parameters of the targets by analysing their H i near-IR emission features, we added the results from the Lupus and Serpens clouds to those from previous regions (investigated in POISSON with the same methodology) to obtain a final catalogue (143 objects) of mass accretion rate values (Ṁacc) derived in a homogeneous and consistent fashion. Our final goal is to analyse how Ṁacc correlates with the stellar mass (M∗) and how it evolves in time in the whole POISSON sample. Methods: We derived the accretion luminosity (Lacc) and Ṁacc for Lupus and Serpens objects from the Brγ (Paβ in a few cases) line by using relevant empirical relationships available in the literature that connect the H i line luminosity and Lacc. To minimise the biases that arise from adopting literature data that are based on different evolutionary models and also for self-consistency, we re-derived mass and age for each source of the POISSON samples using the same set of evolutionary tracks. Results: We observe a correlation Ṁacc~M*2.2 between mass accretion rate and stellar mass, similarly to what has previously been observed in several star-forming regions. We find that the time variation of Ṁacc is roughly consistent with the expected evolution of the accretion rate in viscous disks, with an asymptotic decay that behaves as t-1.6. However, Ṁacc values are characterised by a large scatter at similar ages and are on average higher than the predictions of viscous models. Conclusions: Although part of the scattering may be related to systematics due to the

  11. Biochemical and metabolic abnormalities in articular cartilage from osteoarthritic human hips. III. Distribution and metabolism of amino sugar-containing macromolecules.

    PubMed

    Mankin, H J; Johnson, M E; Lippiello, L

    1981-01-01

    Since 1960, numerous studies have supported the thesis that the synthetic activity of articular chondrocytes is increased in osteoarthritis, but several recent reports have challenged this concept. To clarify this problem fully and also to define further the products of this increased synthesis, three experiments were performed in which the distribution and rates of synthesis of amino sugar-containing macromolecules in normal and osteoarthritic cartilage from the human femoral head were assessed by biochemical analysis and studies of the incorporation of 3H-glucosamine and 35SO4. The biochemical data obtained clearly demonstrated the previously noted significant decrease in hexosamine content in osteoarthritic tissue. This decrease was principally due to a diminution in glucosamine concentration and correlated inversely with the severity of the disease process (as measured by a previously described histological-histochemical grading system). Metabolic studies showed a marked increment in the rates of incorporation of 3H-glucosamine into both the glucosamine and the galactosamine fractions of the cartilage. The increased synthesis correlated directly in a non-linear fashion with the severity of the disease. The ratio of the rate of incorporation of 3H-glucosamine into the glucosamine fraction to the rate of its incorporation into the galactosamine fraction was the same in normal and osteoarthritic samples, suggesting that the decline in glucosamine concentration was not related to a qualitative alteration of synthetic activity.

  12. Biochemical and Structural Characterization of Germicidin Synthase: Analysis of a Type III Polyketide Synthase That Employs Acyl-ACP as a Starter Unit Donor

    SciTech Connect

    Chemler, Joseph A.; Buchholz, Tonia J.; Geders, Todd W.; Akey, David L.; Rath, Christopher M.; Chlipala, George E.; Smith, Janet L.; Sherman, David H.

    2012-08-10

    Germicidin synthase (Gcs) from Streptomyces coelicolor is a type III polyketide synthase (PKS) with broad substrate flexibility for acyl groups linked through a thioester bond to either coenzyme A (CoA) or acyl carrier protein (ACP). Germicidin synthesis was reconstituted in vitro by coupling Gcs with fatty acid biosynthesis. Since Gcs has broad substrate flexibility, we directly compared the kinetic properties of Gcs with both acyl-ACP and acyl-CoA. The catalytic efficiency of Gcs for acyl-ACP was 10-fold higher than for acyl-CoA, suggesting a strong preference toward carrier protein starter unit transfer. The 2.9 {angstrom} germicidin synthase crystal structure revealed canonical type III PKS architecture along with an unusual helical bundle of unknown function that appears to extend the dimerization interface. A pair of arginine residues adjacent to the active site affect catalytic activity but not ACP binding. This investigation provides new and surprising information about the interactions between type III PKSs and ACPs that will facilitate the construction of engineered systems for production of novel polyketides.

  13. Degradation of connective tissue matrices by macrophages. III. Morphological and biochemical studies on extracellular, pericellular, and intracellular events in matrix proteolysis by macrophages in culture

    PubMed Central

    1980-01-01

    We have shown that macrophages in culture degrade the glycoproteins and amorphous elastin of insoluble extracellular matrices. Ultrastructural observation of the macrophage-matrix interaction revealed that connective tissue macromolecules were solubilized from the matrix extracellularly. At least part of the matrix breakdown was localized to the immediate vicinity of the cells, as shown by morphological and biochemical studies, although the rate of degradation correlated closely with the secretion of proteinases by various inflammatory stimuli in vivo, by glucocorticoids, prostaglandin E2 or colchicine, or by phagocytosis of latex, zymosan, or cholesterol-albumin complexes in culture was reflected in altered rates of glycoprotein and elastin degradation by the macrophages. Alteration of endocytosis and lysosomal digestion by cytochalasin B, NH4Cl, and proteinase inhibitors did not decrease the overall rate of matrix solubilization, but reduced the processing of the matrix fragments to peptides. Therefore, extracellular, pericellular, and lysosomal events each contribute to degradation of extracellular matrix macromolecules by inflammatory macrophages. PMID:7005386

  14. The evolution of the role of ABA in the regulation of water-use efficiency: From biochemical mechanisms to stomatal conductance.

    PubMed

    Negin, Boaz; Moshelion, Menachem

    2016-10-01

    Abscisic acid is found in a wide variety of organisms. In the plant kingdom, ABA's role in mediating responses to abiotic stress has been conserved and enhanced throughout evolution. The emergence of plants to terrestrial environments required the development of mechanisms to cope with ongoing and severe abiotic stress such as drought and rapid changes in humidity and temperature. The common understanding is that terrestrial plants evolved strategies ranging from desiccation-tolerance mechanisms (mosses) to drought tolerance (CAM plants), to better exploit different ecological niches. In between these divergent water regulation strategies, ABA plays a significant role in managing plants' adaptation to new environments by optimizing water-use efficiency (WUE) under particular environmental conditions. ABA plays some very different roles in the regulation of WUE. ABA's role in the regulation of guard cells and transpiration has yielded a wide variety of WUE-regulation mechanisms, ranging from no sensitivity (ferns) to low sensitivity (anisohydric behavior) to hypersensitivity to ABA (isohydric behavior and putatively CAM plants). ABA also plays a role in the regulation of non-stomatal, biochemical mechanisms of WUE regulation. In angiosperms, this includes the control of osmotic adjustment and morphological changes, including changes in leaf size, stomatal density, stomatal size and root development. Under severe stress, ABA also appears to initiate leaf senescence via transcriptional regulation, to directly inhibit photosynthesis.

  15. Biochemical, cellular, and molecular mechanisms in the evolution of secondary damage after severe traumatic brain injury in infants and children: Lessons learned from the bedside.

    PubMed

    Kochanek, Patrick M.; Clark, Robert S.B.; Ruppel, Randall A.; Adelson, P. David; Bell, Michael J.; Whalen, Michael J.; Robertson, Courtney L.; Satchell, Margaret A.; Seidberg, Neal A.; Marion, Donald W.; Jenkins, Larry W.

    2000-07-01

    OBJECTIVE: To present a state-of-the-art review of mechanisms of secondary injury in the evolution of damage after severe traumatic brain injury in infants and children. DATA SOURCES: We reviewed 152 peer-reviewed publications, 15 abstracts and proceedings, and other material relevant to the study of biochemical, cellular, and molecular mechanisms of damage in traumatic brain injury. Clinical studies of severe traumatic brain injury in infants and children were the focus, but reports in experimental models in immature animals were also considered. Results from both clinical studies in adults and models of traumatic brain injury in adult animals were presented for comparison. DATA SYNTHESIS: Categories of mechanisms defined were those associated with ischemia, excitotoxicity, energy failure, and resultant cell death cascades; secondary cerebral swelling; axonal injury; and inflammation and regeneration. CONCLUSIONS: A constellation of mediators of secondary damage, endogenous neuroprotection, repair, and regeneration are set into motion in the brain after severe traumatic injury. The quantitative contribution of each mediator to outcome, the interplay between these mediators, and the integration of these mechanistic findings with novel imaging methods, bedside physiology, outcome assessment, and therapeutic intervention remain an important target for future research.

  16. Evolution.

    ERIC Educational Resources Information Center

    Mayr, Ernst

    1978-01-01

    Traces the history of evolution theory from Lamarck and Darwin to the present. Discusses natural selection in detail. Suggests that, besides biological evolution, there is also a cultural evolution which is more rapid than the former. (MA)

  17. Simultaneous occurrence of the 11778 (ND4) and the 9438 (COX III) mtDNA mutations in Leber hereditary optic neuropathy: Molecular, biochemical, and clinical findings

    SciTech Connect

    Oostra, R.J.; Bleeker-Wagemakers, E.M.; Zwart, R.

    1995-10-01

    Three mtDNA point mutations at nucleotide position (np) 3460, at np 11778 and at np 14484, are thought to be of primary importance in the pathogenesis of Leber hereditary optic neuropathy (LHON), a maternally inherited disease characterized by subacute central vision loss. These mutations are present in genes coding for subunits of complex I (NADH dehydrogenase) of the respiratory chain, occur exclusively in LHON maternal pedigrees, and have never been reported to occur together. Johns and Neufeld postulated that an mtDNA mutation at np 9438, in the gene coding for one of the subunits (COX III) of complex IV (cytochrome c oxidase), was also of primary importance. Johns and Neufeld (1993) found this mutation, which changed a conserved glycine to a serine, in 5 unrelated LHON probands who did not carry one of the presently known primary mutations, but they did not find it in 400 controls. However, the role of this sequence variant has been questioned in the Journal when it has been found to occur in apparently healthy African and Cuban individuals. Subsequently, Johns et al. described this mutation in two Cuban individuals presenting with optic and peripheral neuropathy. 22 refs., 1 fig., 1 tab.

  18. Biochemical evolution III: Polymerization on organophilic silica-rich surfaces, crystal–chemical modeling, formation of first cells, and geological clues

    PubMed Central

    Smith, Joseph V.; Arnold, Frederick P.; Parsons, Ian; Lee, Martin R.

    1999-01-01

    Catalysis at organophilic silica-rich surfaces of zeolites and feldspars might generate replicating biopolymers from simple chemicals supplied by meteorites, volcanic gases, and other geological sources. Crystal–chemical modeling yielded packings for amino acids neatly encapsulated in 10-ring channels of the molecular sieve silicalite-ZSM-5-(mutinaite). Calculation of binding and activation energies for catalytic assembly into polymers is progressing for a chemical composition with one catalytic Al–OH site per 25 neutral Si tetrahedral sites. Internal channel intersections and external terminations provide special stereochemical features suitable for complex organic species. Polymer migration along nano/micrometer channels of ancient weathered feldspars, plus exploitation of phosphorus and various transition metals in entrapped apatite and other microminerals, might have generated complexes of replicating catalytic biomolecules, leading to primitive cellular organisms. The first cell wall might have been an internal mineral surface, from which the cell developed a protective biological cap emerging into a nutrient-rich “soup.” Ultimately, the biological cap might have expanded into a complete cell wall, allowing mobility and colonization of energy-rich challenging environments. Electron microscopy of honeycomb channels inside weathered feldspars of the Shap granite (northwest England) has revealed modern bacteria, perhaps indicative of Archean ones. All known early rocks were metamorphosed too highly during geologic time to permit simple survival of large-pore zeolites, honeycombed feldspar, and encapsulated species. Possible microscopic clues to the proposed mineral adsorbents/catalysts are discussed for planning of systematic study of black cherts from weakly metamorphosed Archaean sediments. PMID:10097060

  19. A unified N-body and statistical treatment of stellar dynamics. III - Early postcollapse evolution of globular clusters

    NASA Technical Reports Server (NTRS)

    Mcmillan, S. L. W.

    1986-01-01

    The period immediately following the core collapse phase in the evolution of a globular cluster is studied using a hybrid N-body/Fokker-Planck stellar dynamical code. Several core oscillations of the type predicted in earlier work are seen. The oscillations are driven by the formation, hardening, and ejection of binaries by three-body processes, and appear to decay on a timescale of about 10 to the 7th yr, for the choice of 'typical' cluster parameters made here. There is no evidence that they are gravothermal in nature. The mechanisms responsible for the decay are discussed in some detail. The distribution of hard binaries produced by the oscillations is compared with theoretical expectations and the longer term evolution of the system is considered.

  20. Infrared Spectroscopic Data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE), SDSS-III Data Release 10

    DOE Data Explorer

    Sloan Digital Sky Survey (SDSS) Data Release 10 is the first spectroscopic release from the Apache Point Observatory Galactic Evolution Experiment (APOGEE), including spectra and derived stellar parameters for more than 50,000 stars. APOGEE is an ongoing survey of ~100,000 stars accessing all parts of the Milky Way. By operating in the infrared (H-band) portion of the electromagnetic spectrum, APOGEE is better able to detect light from stars lying in dusty regions of the Milky Way than surveys conducted in the optical, making this survey particularly well-suited for exploring the Galactic disk and bulge. APOGEE's high resolution spectra provide detailed information about the stellar atmospheres; DR10 provides derived effective temperatures, surface gravities, overall metallicities, and information on the abundances of several chemical elements. [copied from http://www.sdss3.org/dr10/irspec/

  1. Model Stellar Spectral Libraries for Analysis of the SDSS-III Apache Point Observatory Galactic Evolution Experiment (APOGEE)

    NASA Astrophysics Data System (ADS)

    Allende-Prieto, Carlos; Koesterke, L.; Shetrone, M. D.; Zamora, O.; Ruffoni, M. P.; Smith, V. V.; Cunha, K. M.; Lawler, J. E.; Pickering, J. C.; Nave, G.; Garcia Perez, A.; Bizyaev, D.; Edvardsson, B.; Gustafsson, B.; Plez, B.; Castelli, F.; Majewski, S. R.; Schiavon, R. P.; Meszaros, Sz.; de Vicente, A.

    2014-01-01

    The Apache Point Observatory Galactic Evolution Experiment (APOGEE) is obtaining high resolution ( 22,500), high signal-to-noise (> 100) spectra in the 1510-1690 nm spectral region for 100,000 cool, predominantly post-main sequence stars. To ascertain the stellar atmospheric parameters and measure chemical abundances for the numerous chemical elements with line transitions in this wavelength region, the APOGEE Atmospheric Parameters and Chemical Abundances Pipeline (ASPCAP) relies on an optimization algorithm that identifies the best-fitting model for each of the observed APOGEE spectra. The fitting algorithm speeds up the model evaluation by interpolation in pre-computed grids of synthetic spectra that have been compressed using Principal Component Analysis. Here we describe the main model grids used in ASPCAP for the tenth data release of the Sloan Digital Sky Survey (SDSS DR10), how they were calculated. We also provide a description of ongoing and planned upgrades.

  2. The UV-Optical Galaxy Color-Magnitude Diagram. III. Constraints on Evolution from the Blue to the Red Sequence

    NASA Astrophysics Data System (ADS)

    Martin, D. Christopher; Wyder, Ted K.; Schiminovich, David; Barlow, Tom A.; Forster, Karl; Friedman, Peter G.; Morrissey, Patrick; Neff, Susan G.; Seibert, Mark; Small, Todd; Welsh, Barry Y.; Bianchi, Luciana; Donas, José; Heckman, Timothy M.; Lee, Young-Wook; Madore, Barry F.; Milliard, Bruno; Rich, R. Michael; Szalay, Alex S.; Yi, Sukyoung K.

    2007-12-01

    We introduce a new quantity, the mass flux density of galaxies evolving from the blue sequence to the red sequence. We propose a simple technique for constraining this mass flux using the volume-corrected number density in the extinction-corrected UV-optical color-magnitude distribution, the stellar age indexes HδA and Dn(4000), and a simple prescription for spectral evolution using a quenched star formation history. We exploit the excellent separation of red and blue sequences in the NUV-r band Hess function. The final value we measure, ρT˙=0.033 Msolar yr-1 Mpc-3, is strictly speaking an upper limit due to the possible contributions of bursting, composite, and extincted galaxies. However, it compares favorably with estimates of the average mass flux that we make based on the red luminosity function evolution derived from the DEEP2 and COMBO-17 surveys, ρ˙R=+0.034 Msolar yr-1 Mpc-3. We find that the blue sequence mass has remained roughly constant since z=1 (ρB˙~=0.01 Msolar yr-1 Mpc-3, but the average on-going star formation of ρ˙SF~=0.037 Msolar yr-1 Mpc-3 over 0

  3. Decomposition driven interface evolution for layers of binary mixtures. III. Two-dimensional steady films with flat and modulated surfaces

    NASA Astrophysics Data System (ADS)

    Bribesh, Fathi A. M.; Fraštia, Ľubor; Thiele, Uwe

    2012-06-01

    We study two-dimensional steady concentration and film thickness profiles for isothermal free surface films of a binary liquid mixture on a solid substrate employing model-H that couples the diffusive transport of the components of the mixture (convective Cahn-Hilliard equation) and the transport of momentum (Navier-Stokes-Korteweg equations). The analysis is based on minimising the underlying free energy equivalent to solving the static limit of model-H. Additionally, the linear stability (in time) of relevant layered films is analyzed. This allows for a comparison of the position of certain branching points in the bifurcation diagrams of steady solutions with the value predicted as onset of a linear instability. Results are presented for the cases of (i) a flat film without energetic bias at the free surface, (ii) a flat film with energetic bias, (iii) a height-modulated film without energetic bias, and (iv) a height-modulated film with energetic bias. In all cases we discuss symmetries of the various steady solutions allowing us to order them and to infer properties of solution branches and relations between them.

  4. Biosynthesis of biphenyls and benzophenones--evolution of benzoic acid-specific type III polyketide synthases in plants.

    PubMed

    Beerhues, Ludger; Liu, Benye

    2009-01-01

    Type III polyketide synthases (PKSs) generate a diverse array of secondary metabolites by varying the starter substrate, the number of condensation reactions, and the mechanism of ring closure. Among the starter substrates used, benzoyl-CoA is a rare starter molecule. Biphenyl synthase (BIS) and benzophenone synthase (BPS) catalyze the formation of identical linear tetraketide intermediates from benzoyl-CoA and three molecules of malonyl-CoA but use alternative intramolecular cyclization reactions to form 3,5-dihydroxybiphenyl and 2,4,6-trihydroxybenzophenone, respectively. In a phylogenetic tree, BIS and BPS group together closely, indicating that they arise from a relatively recent functional diversification of a common ancestral gene. The functionally diverse PKSs, which include BIS and BPS, and the ubiquitously distributed chalcone synthases (CHSs) form separate clusters, which originate from a gene duplication event prior to the speciation of the angiosperms. BIS is the key enzyme of biphenyl metabolism. Biphenyls and the related dibenzofurans are the phytoalexins of the Maloideae. This subfamily of the Rosaceae includes a number of economically important fruit trees, such as apple and pear. When incubated with ortho-hydroxybenzoyl (salicoyl)-CoA, BIS catalyzes a single decarboxylative condensation with malonyl-CoA to form 4-hydroxycoumarin. A well-known anticoagulant derivative of this enzymatic product is dicoumarol. Elicitor-treated cell cultures of Sorbus aucuparia also formed 4-hydroxycoumarin when fed with the N-acetylcysteamine thioester of salicylic acid (salicoyl-NAC). BPS is the key enzyme of benzophenone metabolism. Polyprenylated benzophenone derivatives with bridged polycyclic skeletons are widely distributed in the Clusiaceae (Guttiferae). Xanthones are regioselectively cyclized benzophenone derivatives. BPS was converted into a functional phenylpyrone synthase (PPS) by a single amino acid substitution in the initiation/elongation cavity. The

  5. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry

    PubMed Central

    2016-01-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of ‘polar ice’ mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm ‘carbonyl’ absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes. PMID:28083090

  6. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry

    NASA Astrophysics Data System (ADS)

    Jones, A. P.

    2016-12-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of `polar ice' mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm `carbonyl' absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes.

  7. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry.

    PubMed

    Jones, A P

    2016-12-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of 'polar ice' mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm 'carbonyl' absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes.

  8. The MUSIC of Galaxy Clusters - III. Properties, evolution and Y-M scaling relation of protoclusters of galaxies

    NASA Astrophysics Data System (ADS)

    Sembolini, Federico; De Petris, Marco; Yepes, Gustavo; Foschi, Emma; Lamagna, Luca; Gottlöber, Stefan

    2014-06-01

    In this work, we study the properties of protoclusters of galaxies by employing the MultiDark SImulations of galaxy Clusters (MUSIC) set of hydrodynamical simulations, featuring a sample of 282 resimulated clusters with available merger trees up to z = 4. We study the characteristics and redshift evolution of the mass and the spatial distribution for all the protoclusters, which we define as the most massive progenitors of the clusters identified at z = 0. We extend the study of the baryon content to redshifts larger than 1 also in terms of gas and stars budgets: no remarkable variations with redshift are discovered. Furthermore, motivated by the proven potential of Sunyaev-Zel'dovich surveys to blindly search for faint distant objects, we compute the scaling relation between total object mass and integrated Compton y-parameter. We find that the slope of this scaling law is steeper than what expected for a self-similarity assumption among these objects, and it increases with redshift mainly when radiative processes are included. We use three different criteria to account for the dynamical state of the protoclusters, and find no significant dependence of the scaling parameters on the level of relaxation. We exclude the dynamical state as the cause of the observed deviations from self-similarity in protoclusters.

  9. Surface decoration of amine-rich carbon nitride with iron nanoparticles for arsenite (As(III)) uptake: The evolution of the Fe-phases under ambient conditions.

    PubMed

    Georgiou, Y; Mouzourakis, E; Bourlinos, A B; Zboril, R; Karakassides, M A; Douvalis, A P; Bakas, Th; Deligiannakis, Y

    2016-07-15

    A novel hybrid material (gC3N4-rFe) consisting of amine-rich graphitic carbon nitride (gC3N4), decorated with reduced iron nanoparticles (rFe) is presented. XRD and TEM show that gC3N4-rFe bears aggregation-free Fe-nanoparticles (10nm) uniformly dispersed over the gC3N4 surface. In contrast, non-supported iron nanoparticles are strongly aggregated, with non-uniform size distribution (20-100nm). (57)Fe-Mössbauer spectroscopy, dual-mode electron paramagnetic resonance (EPR) and magnetization measurements, allow a detailed mapping of the evolution of the Fe-phases after exposure to ambient O2. The as-prepared gC3N4-rFe bears Fe(2+) and Fe° phases, however only after long exposure to ambient O2, a Fe-oxide layer is formed around the Fe° core. In this [Fe°/Fe-oxide] core-shell configuration, the gC3N4-rFe hybrid shows enhanced As(III) uptake capacity of 76.5mgg(-1), i.e., ca 90% higher than the unmodified carbonaceous support, and 300% higher than the non-supported Fe-nanoparticles. gC3N4-rFe is a superior As(III) sorbent i.e., compared to its single counterparts or vs. graphite/graphite oxide or activated carbon analogues (11-36mgg(-1)). The present results demonstrate that the gC3N4 matrix is not simply a net that holds the particles, but rather an active component that determines particle formation dynamics and ultimately their redox profile, size and surface dispersion homogeneity.

  10. Deciphering the biodiversity of Listeria monocytogenes lineage III strains by polyphasic approaches.

    PubMed

    Zhao, Hanxin; Chen, Jianshun; Fang, Chun; Xia, Ye; Cheng, Changyong; Jiang, Lingli; Fang, Weihuan

    2011-10-01

    Listeria monocytogenes is a foodborne pathogen of humans and animals. The majority of human listeriosis cases are caused by strains of lineages I and II, while lineage III strains are rare and seldom implicated in human listeriosis. We revealed by 16S rRNA sequencing the special evolutionary status of L. monocytogenes lineage III, which falls between lineages I and II strains of L. monocytogenes and the non-pathogenic species L. innocua and L. marthii in the dendrogram. Thirteen lineage III strains were then characterized by polyphasic approaches. Biochemical reactions demonstrated 8 biotypes, internalin profiling identified 10 internal-in types clustered in 4 groups, and multilocus sequence typing differentiated 12 sequence types. These typing schemes show that lineage III strains represent the most diverse population of L. monocytogenes, and comprise at least four subpopulations IIIA-1, IIIA-2, HIB, and IIIC. The in vitro and in vivo virulence assessments showed that two lineage IIIA-2 strains had reduced pathogenicity, while the other lineage III strains had comparable virulence to lineages I and II. The HIB strains are phylogenetically distinct from other sub-populations, providing additional evidence that this sublineage represents a novel lineage. The two biochemical reactions L-rhamnose and L-lactate alkalinization, and 10 internalins were identified as potential markers for lineage III subpopulations. This study provides new insights into the biodiversity and population structure of lineage III strains, which are important for understanding the evolution of the L. mono-cytogenes-L. innocua clade.

  11. Star formation in the first galaxies - III. Formation, evolution, and characteristics of the first metal-enriched stellar cluster

    NASA Astrophysics Data System (ADS)

    Safranek-Shrader, Chalence; Montgomery, Michael H.; Milosavljević, Miloš; Bromm, Volker

    2016-01-01

    We simulate the formation of a low-metallicity (10-2 Z⊙) stellar cluster at redshift z ˜ 14. Beginning with cosmological initial conditions, the simulation utilizes adaptive mesh refinement and sink particles to follow the collapse and evolution of gas past the opacity limit for fragmentation, thus resolving the formation of individual protostellar cores. A time- and location-dependent protostellar radiation field, which heats the gas by absorption on dust, is computed by integration of protostellar evolutionary tracks. The simulation also includes a robust non-equilibrium chemical network that self-consistently treats gas thermodynamics and dust-gas coupling. The system is evolved for 18 kyr after the first protostellar source has formed. In this time span, 30 sink particles representing protostellar cores form with a total mass of 81 M⊙. Their masses range from ˜0.1 to 14.4 M⊙ with a median mass ˜0.5-1 M⊙. Massive protostars grow by competitive accretion while lower mass protostars are stunted in growth by close encounters and many-body ejections. In the regime explored here, the characteristic mass scale is determined by the cosmic microwave background temperature floor and the onset of efficient dust-gas coupling. It seems unlikely that host galaxies of the first bursts of metal-enriched star formation will be detectable with the James Webb Space Telescope or other next-generation infrared observatories. Instead, the most promising access route to the dawn of cosmic star formation may lie in the scrutiny of metal-poor, ancient stellar populations in the Galactic neighbourhood. The observable targets corresponding to the system simulated here are ultra-faint dwarf satellite galaxies such as Boötes II and Willman I.

  12. Chemical weathering rates of a soil chronosequence on granitic alluvium: III. Hydrochemical evolution and contemporary solute fluxes and rates

    USGS Publications Warehouse

    White, A.F.; Schulz, M.S.; Vivit, D.V.; Blum, A.E.; Stonestrom, D.A.; Harden, J.W.

    2005-01-01

    Although long-term changes in solid-state compositions of soil chronosequences have been extensively investigated, this study presents the first detailed description of the concurrent hydrochemical evolution and contemporary weathering rates in such sequences. The most direct linkage between weathering and hydrology over 3 million years of soil development in the Merced chronosequence in Central California relates decreasing permeability and increasing hydrologic heterogeneity to the development of secondary argillic horizons and silica duripans. In a highly permeable, younger soil (40 kyr old), pore water solutes reflect seasonal to decadal-scale variations in rainfall and evapotranspiration (ET). This climate signal is strongly damped in less permeable older soils (250 to 600 kyr old) where solutes increasingly reflect weathering inputs modified by heterogeneous flow. Elemental balances in the soils are described in terms of solid state, exchange and pore water reservoirs and input/output fluxes from precipitation, ET, biomass, solute discharge and weathering. Solute mineral nutrients are strongly dependent on biomass variations as evidenced by an apparent negative K weathering flux reflecting aggradation by grassland plants. The ratios of solute Na to other base cations progressively increase with soil age. Discharge fluxes of Na and Si, when integrated over geologic time, are comparable to solid-state mass losses in the soils, implying similar past weathering conditions. Similarities in solute and sorbed Ca/Mg ratios reflect short-term equilibrium with the exchange reservoir. Long-term consistency in solute ratios, when contrasted against progressive decreases in solid-state Ca/Mg, requires an additional Ca source, probably from dry deposition. Amorphous silica precipitates from thermodynamically-saturated pore waters during periods of high evapotranspiration and result in the formation of duripans in the oldest soils. The degree of feldspar and secondary

  13. THE TENTH DATA RELEASE OF THE SLOAN DIGITAL SKY SURVEY: FIRST SPECTROSCOPIC DATA FROM THE SDSS-III APACHE POINT OBSERVATORY GALACTIC EVOLUTION EXPERIMENT

    SciTech Connect

    Ahn, Christopher P.; Anderton, Timothy; Alexandroff, Rachael; Allende Prieto, Carlos; Anderson, Scott F.; Bhardwaj, Vaishali; Andrews, Brett H.; Aubourg, Éric; Bautista, Julian E.; Bastien, Fabienne A.; Berlind, Andreas A.; Bird, Jonathan C.; Beers, Timothy C.; Beifiori, Alessandra; Bender, Chad F.; Bizyaev, Dmitry; Blake, Cullen H.; and others

    2014-04-01

    The Sloan Digital Sky Survey (SDSS) has been in operation since 2000 April. This paper presents the Tenth Public Data Release (DR10) from its current incarnation, SDSS-III. This data release includes the first spectroscopic data from the Apache Point Observatory Galaxy Evolution Experiment (APOGEE), along with spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS) taken through 2012 July. The APOGEE instrument is a near-infrared R ∼ 22,500 300 fiber spectrograph covering 1.514-1.696 μm. The APOGEE survey is studying the chemical abundances and radial velocities of roughly 100,000 red giant star candidates in the bulge, bar, disk, and halo of the Milky Way. DR10 includes 178,397 spectra of 57,454 stars, each typically observed three or more times, from APOGEE. Derived quantities from these spectra (radial velocities, effective temperatures, surface gravities, and metallicities) are also included. DR10 also roughly doubles the number of BOSS spectra over those included in the Ninth Data Release. DR10 includes a total of 1,507,954 BOSS spectra comprising 927,844 galaxy spectra, 182,009 quasar spectra, and 159,327 stellar spectra selected over 6373.2 deg{sup 2}.

  14. Structure and Activity Analyses of Escherichia coli K-12 NagD Provide Insight into the Evolution of Biochemical Function in the Haloakanoic Acid Dehlogenase Superfamily

    SciTech Connect

    Tremblay,L.; Dunaway-Mariano, D.; Allen, K.

    2006-01-01

    The HAD superfamily is a large superfamily of proteins which share a conserved core domain that provides those active site residues responsible for the chemistry common to all family members. The superfamily is further divided into the four subfamilies I, IIA, IIB, and III, based on the topology and insertion site of a cap domain that provides substrate specificity. This structural and functional division implies that members of a given HAD structural subclass may target substrates that have similar structural characteristics. To understand the structure/function relationships in all of the subfamilies, a type IIA subfamily member, NagD from Escherichia coli K-12, was selected (type I, IIB, and III members have been more extensively studied). The structure of the NagD protein was solved to 1.80 Angstroms with R{sub work} = 19.8% and R{sub free} = 21.8%. Substrate screening and kinetic analysis showed NagD to have high specificity for nucleotide monophosphates with kcat/Km = 3.12 x 10{sup 4} and 1.28 x 10{sup 4} {micro}M{sup -1} s{sup -1} for UMP and GMP, respectively. This specificity is consistent with the presence of analogues of NagD that exist as fusion proteins with a nucleotide pyrophosphatase from the Nudix family. Docking of the nucleoside substrate in the active site brings it in contact with conserved residues from the cap domain that can act as a substrate specificity loop (NagD residues 144-149) in the type IIA subfamily. NagD and other subfamily IIA and IIB members show the common trait that substrate specificity and catalytic efficiencies (k{sub cat}/K{sub m}) are low (1 x 10{sup 4} M{sup -1} s{sup -1}) and the boundaries defining physiological substrates are somewhat overlapping. The ability to catabolize other related secondary metabolites indicates that there is regulation at the genetic level.

  15. Structure and activity analyses of Escherichia coli K-12 NagD provide insight into the evolution of biochemical function in the haloalkanoic acid dehalogenase superfamily.

    PubMed

    Tremblay, Lee W; Dunaway-Mariano, Debra; Allen, Karen N

    2006-01-31

    The HAD superfamily is a large superfamily of proteins which share a conserved core domain that provides those active site residues responsible for the chemistry common to all family members. The superfamily is further divided into the four subfamilies I, IIA, IIB, and III, based on the topology and insertion site of a cap domain that provides substrate specificity. This structural and functional division implies that members of a given HAD structural subclass may target substrates that have similar structural characteristics. To understand the structure/function relationships in all of the subfamilies, a type IIA subfamily member, NagD from Escherichia coli K-12, was selected (type I, IIB, and III members have been more extensively studied). The structure of the NagD protein was solved to 1.80 A with R(work) = 19.8% and R(free) = 21.8%. Substrate screening and kinetic analysis showed NagD to have high specificity for nucleotide monophosphates with k(cat)/K(m) = 3.12 x 10(4) and 1.28 x 10(4) microM(-)(1) s(-)(1) for UMP and GMP, respectively. This specificity is consistent with the presence of analogues of NagD that exist as fusion proteins with a nucleotide pyrophosphatase from the Nudix family. Docking of the nucleoside substrate in the active site brings it in contact with conserved residues from the cap domain that can act as a substrate specificity loop (NagD residues 144-149) in the type IIA subfamily. NagD and other subfamily IIA and IIB members show the common trait that substrate specificity and catalytic efficiencies (k(cat)/K(m)) are low (1 x 10(4) M(-)(1) s(-)(1)) and the boundaries defining physiological substrates are somewhat overlapping. The ability to catabolize other related secondary metabolites indicates that there is regulation at the genetic level.

  16. Biochemical, Transcriptomic and Proteomic Analyses of Digestion in the Scorpion Tityus serrulatus: Insights into Function and Evolution of Digestion in an Ancient Arthropod

    PubMed Central

    Fuzita, Felipe J.; Pinkse, Martijn W. H.; Patane, José S. L.; Juliano, Maria A.; Verhaert, Peter D. E. M.; Lopes, Adriana R.

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

  17. Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

    PubMed

    Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

    2015-01-01

    Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

  18. Evolution of the H β + [O III] and [O II] luminosity functions and the [O II] star formation history of the Universe up to z ˜ 5 from HiZELS

    NASA Astrophysics Data System (ADS)

    Khostovan, A. A.; Sobral, D.; Mobasher, B.; Best, P. N.; Smail, I.; Stott, J. P.; Hemmati, S.; Nayyeri, H.

    2015-10-01

    We investigate the evolution of the H β + [O III] and [O II] luminosity functions from z ˜ 0.8 to ˜5 in four redshift slices per emission line using data from the High-z Emission Line Survey (HiZELS). This is the first time that the H β + [O III] and [O II] luminosity functions have been studied at these redshifts in a self-consistent analysis. This is also the largest sample of [O II] and H β + [O III] emitters (3475 and 3298 emitters, respectively) in this redshift range, with large comoving volumes ˜1 × 106 Mpc-3 in two independent volumes (COSMOS and UDS), greatly reducing the effects of cosmic variance. The emitters were selected by a combination of photometric redshift and colour-colour selections, as well as spectroscopic follow-up, including recent spectroscopic observations using DEIMOS and MOSFIRE on the Keck Telescopes and FMOS on Subaru. We find a strong increase in L⋆ and a decrease in φ⋆ for both H β + [O III] and [O II] emitters. We derive the [O II] star formation history of the Universe since z ˜ 5 and find that the cosmic star formation rate density (SFRD) rises from z ˜ 5 to ˜3 and then drops towards z ˜ 0. We also find that our star formation history is able to reproduce the evolution of the stellar mass density up to z ˜ 5 based only on a single tracer of star formation. When comparing the H β + [O III] SFRDs to the [O II] and H α SFRD measurements in the literature, we find that there is a remarkable agreement, suggesting that the H β + [O III] sample is dominated by star-forming galaxies at high-z rather than AGNs.

  19. Biochemical adaptation to ocean acidification.

    PubMed

    Stillman, Jonathon H; Paganini, Adam W

    2015-06-01

    The change in oceanic carbonate chemistry due to increased atmospheric PCO2  has caused pH to decline in marine surface waters, a phenomenon known as ocean acidification (OA). The effects of OA on organisms have been shown to be widespread among diverse taxa from a wide range of habitats. The majority of studies of organismal response to OA are in short-term exposures to future levels of PCO2 . From such studies, much information has been gathered on plastic responses organisms may make in the future that are beneficial or harmful to fitness. Relatively few studies have examined whether organisms can adapt to negative-fitness consequences of plastic responses to OA. We outline major approaches that have been used to study the adaptive potential for organisms to OA, which include comparative studies and experimental evolution. Organisms that inhabit a range of pH environments (e.g. pH gradients at volcanic CO2 seeps or in upwelling zones) have great potential for studies that identify adaptive shifts that have occurred through evolution. Comparative studies have advanced our understanding of adaptation to OA by linking whole-organism responses with cellular mechanisms. Such optimization of function provides a link between genetic variation and adaptive evolution in tuning optimal function of rate-limiting cellular processes in different pH conditions. For example, in experimental evolution studies of organisms with short generation times (e.g. phytoplankton), hundreds of generations of growth under future conditions has resulted in fixed differences in gene expression related to acid-base regulation. However, biochemical mechanisms for adaptive responses to OA have yet to be fully characterized, and are likely to be more complex than simply changes in gene expression or protein modification. Finally, we present a hypothesis regarding an unexplored area for biochemical adaptation to ocean acidification. In this hypothesis, proteins and membranes exposed to the

  20. Raman spectroscopic biochemical mapping of tissues

    NASA Astrophysics Data System (ADS)

    Stone, Nicholas; Hart Prieto, Maria C.; Kendall, Catherine A.; Shetty, Geeta; Barr, Hugh

    2006-02-01

    Advances in technologies have brought us closer to routine spectroscopic diagnosis of early malignant disease. However, there is still a poor understanding of the carcinogenesis process. For example it is not known whether many cancers follow a logical sequence from dysplasia, to carcinoma in situ, to invasion. Biochemical tissue changes, triggered by genetic mutations, precede morphological and structural changes. These can be probed using Raman or FTIR microspectroscopy and the spectra analysed for biochemical constituents. Local microscopic distribution of various constituents can then be visualised. Raman mapping has been performed on a number of tissues including oesophagus, breast, bladder and prostate. The biochemical constituents have been calculated at each point using basis spectra and least squares analysis. The residual of the least squares fit indicates any unfit spectral components. The biochemical distribution will be compared with the defined histopathological boundaries. The distribution of nucleic acids, glycogen, actin, collagen I, III, IV, lipids and others appear to follow expected patterns.

  1. [Normal values of various biochemical indicators in lowland black-white dairy cows from the government sector of the Gdańsk Coast. III. Changes in those indicators during feeding seasons and in consecutive months and years].

    PubMed

    Wolańczyk-Rutkowiak, K

    1986-01-01

    In six consecutive feeding seasons the results of tests of biochemical parameters from 5329 cows were estimated. Besides, the parameters from 7229 cows for the consecutive calendar months and years in the period of 1973-1977 were evaluated. It was established that the cyclic seasonal changes were showed only by levels of proteins, sodium, magnesium and calcium. In the months from May to August a decrease of glucose level, an increase of total protein and urea levels as well as a low level of sodium existed. The values of the rest parameters changed irregularly, what ordered to be cautious in a drawing of conclusions on the basis of investigations performed in short periods of times. In particular seasons and years, such phenomena as hypoglycemia, hyperproteinemia, increased level of urea, hypochloremia, hypopotassemia, hypomagnesemia, hypocalcemia and hypophosphoremia could exist irregularly.

  2. Biochemical Education in Thailand: Past, Present, and Future.

    ERIC Educational Resources Information Center

    Svasti, Jisnuson; Surarit, Rudee

    1991-01-01

    Traces the history of Thailand's biochemical education from its initial evolution from medicine to modern day. Discusses the following aspects of Thailand's modern biochemical education: biochemistry teaching at Thai schools, university departments and biochemistry courses, textbooks, degree programs, interplay between research and teaching, and…

  3. Biochemical transformation of coals

    DOEpatents

    Lin, Mow S.; Premuzic, Eugene T.

    1999-03-23

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed.

  4. Biochemical transformation of coals

    DOEpatents

    Lin, M.S.; Premuzic, E.T.

    1999-03-23

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.

  5. Early bioenergetic evolution

    PubMed Central

    Sousa, Filipa L.; Thiergart, Thorsten; Landan, Giddy; Nelson-Sathi, Shijulal; Pereira, Inês A. C.; Allen, John F.; Lane, Nick; Martin, William F.

    2013-01-01

    Life is the harnessing of chemical energy in such a way that the energy-harnessing device makes a copy of itself. This paper outlines an energetically feasible path from a particular inorganic setting for the origin of life to the first free-living cells. The sources of energy available to early organic synthesis, early evolving systems and early cells stand in the foreground, as do the possible mechanisms of their conversion into harnessable chemical energy for synthetic reactions. With regard to the possible temporal sequence of events, we focus on: (i) alkaline hydrothermal vents as the far-from-equilibrium setting, (ii) the Wood–Ljungdahl (acetyl-CoA) pathway as the route that could have underpinned carbon assimilation for these processes, (iii) biochemical divergence, within the naturally formed inorganic compartments at a hydrothermal mound, of geochemically confined replicating entities with a complexity below that of free-living prokaryotes, and (iv) acetogenesis and methanogenesis as the ancestral forms of carbon and energy metabolism in the first free-living ancestors of the eubacteria and archaebacteria, respectively. In terms of the main evolutionary transitions in early bioenergetic evolution, we focus on: (i) thioester-dependent substrate-level phosphorylations, (ii) harnessing of naturally existing proton gradients at the vent–ocean interface via the ATP synthase, (iii) harnessing of Na+ gradients generated by H+/Na+ antiporters, (iv) flavin-based bifurcation-dependent gradient generation, and finally (v) quinone-based (and Q-cycle-dependent) proton gradient generation. Of those five transitions, the first four are posited to have taken place at the vent. Ultimately, all of these bioenergetic processes depend, even today, upon CO2 reduction with low-potential ferredoxin (Fd), generated either chemosynthetically or photosynthetically, suggesting a reaction of the type ‘reduced iron → reduced carbon’ at the beginning of bioenergetic evolution

  6. Systems biology and the origins of life? part II. Are biochemical networks possible ancestors of living systems? networks of catalysed chemical reactions: non-equilibrium, self-organization and evolution.

    PubMed

    Ricard, Jacques

    2010-01-01

    The present article discusses the possibility that catalysed chemical networks can evolve. Even simple enzyme-catalysed chemical reactions can display this property. The example studied is that of a two-substrate proteinoid, or enzyme, reaction displaying random binding of its substrates A and B. The fundamental property of such a system is to display either emergence or integration depending on the respective values of the probabilities that the enzyme has bound one of its substrate regardless it has bound the other substrate, or, specifically, after it has bound the other substrate. There is emergence of information if p(A)>p(AB) and p(B)>p(BA). Conversely, if p(A)evolution. Defined as open non-equilibrium structures, such biochemical networks possess two remarkable properties: (1) the probability of occurrence of their nodes is dependant upon the input and output of matter

  7. Spinal muscular atrophy type II (intermediary) and III (Kugelberg-Welander). Evolution of 50 patients with physiotherapy and hydrotherapy in a swimming pool.

    PubMed

    Cunha, M C; Oliveira, A S; Labronici, R H; Gabbai, A A

    1996-09-01

    We added hydrotherapy to 50 patients with spinal muscular atrophy (SMA) who were being treated with individual conventional physiotherapy. Hydrotherapy performed at an approximate temperature of 30 degrees Celsius, twice a week, for thirty minutes in children and forty-five minutes in adults during a 2-year period. The outcome derived from this combined modality of treatment was rated according to physiotherapeutic evaluations, the MMT (Manual Muscular Test), and the Barthel Ladder. Patients were reevaluated at 2-month intervals. After two years of ongoing treatment, we were able to observe that the deformities in hip, knee and foot were progressive in all SMA Type II patients, and in some Type III. Muscle strength stabilized in most SMA Type III patients, and improved in some. MMT was not done in SMA Type II. In all patients we were able to detect an improvement in the Barthel Ladder scale. This study suggests that a measurable improvement in the quality of daily living may be obtained in patients with SMA Types II and III subjected to conventional physiotherapy when associated with hydrotherapy.

  8. BIOPLUME III

    EPA Pesticide Factsheets

    BIOPLUME III is a two-dimensional finite difference model for simulating the natural attenuation of organic contaminants in groundwater due to the processes of advection, dispersion, sorption, and biodegradation.

  9. Evolution of killer cell Ig-like receptor (KIR) genes: definition of an orangutan KIR haplotype reveals expansion of lineage III KIR associated with the emergence of MHC-C.

    PubMed

    Guethlein, Lisbeth A; Older Aguilar, Anastazia M; Abi-Rached, Laurent; Parham, Peter

    2007-07-01

    Orangutan (Pongo pygmaeus) MHC-C appears less evolved than human HLA-C: Popy-C is not fixed and its alleles encode only one (C1) of the two motifs for killer cell Ig-like receptor (KIR) ligands. To assess the structure and complexity of the orangutan KIR locus, the complete nucleotide sequence of an orangutan KIR haplotype was determined. The PopyKIR locus is flanked by LILR and FCAR and consists of seven genes and pseudogenes, two novel and five corresponding to known cDNA. Distinguishing all KIRs in this rapidly evolving KIR locus from the KIR3DX1 gene is an LTR33A/MLT1D element in intron 3. These two forms of KIR represent lineages that originated by duplication of a common ancestor. The conserved, framework regions of primate KIR loci comprise the 5' part of a lineage V KIR, the 3' part of a pseudogene, the complete 2DL4 gene, and the 3' part of a lineage II KIR. Although previously defined PopyKIR2DL4 alleles contain premature termination codons, the sequenced haplotype's PopyKIR2DL4 allele encodes a full-length protein. A model for KIR evolution is proposed. Distinguishing the orangutan KIR haplotype from the proposed common ancestor of primate KIR haplotypes is an increased number to give three lineage III KIR genes in the centromeric part of the locus, the site for most human lineage III genes encoding HLA-C specific KIR. Thus, expansion of lineage III KIR is associated with emergence of MHC-C.

  10. The evolution of the [O II], H β and [O III] emission line luminosity functions over the last nine billions years

    NASA Astrophysics Data System (ADS)

    Comparat, Johan; Zhu, Guangtun; Gonzalez-Perez, Violeta; Norberg, Peder; Newman, Jeffrey; Tresse, Laurence; Richard, Johan; Yepes, Gustavo; Kneib, Jean-Paul; Raichoor, Anand; Prada, Francisco; Maraston, Claudia; Yèche, Christophe; Delubac, Timothée; Jullo, Eric

    2016-09-01

    Emission line galaxies are one of the main tracers of the large-scale structure to be targeted by the next-generation dark energy surveys. To provide a better understanding of the properties and statistics of these galaxies, we have collected spectroscopic data from the VVDS and DEEP2 deep surveys and estimated the galaxy luminosity functions (LFs) of three distinct emission lines, [O II}] (λ λ 3726,3729) (0.5 < z < 1.3), Hβ (λ4861) (0.3 < z < 0.8) and [O {III}] (λ 5007) (0.3 < z < 0.8). Our measurements are based on 35 639 emission line galaxies and cover a volume of ˜107 Mpc3. We present the first measurement of the Hβ LF at these redshifts. We have also compiled LFs from the literature that were based on independent data or covered different redshift ranges, and we fit the entire set over the whole redshift range with analytic Schechter and Saunders models, assuming a natural redshift dependence of the parameters. We find that the characteristic luminosity (L*) and density (φ*) of all LFs increase with redshift. Using the Schechter model over the redshift ranges considered, we find that, for [O {II}] emitters, the characteristic luminosity L*(z = 0.5) = 3.2 × 1041 erg s-1 increases by a factor of 2.7 ± 0.2 from z = 0.5 to 1.3; for Hβ emitters L*(z = 0.3) = 1.3 × 1041 erg s-1 increases by a factor of 2.0 ± 0.2 from z = 0.3 to 0.8; and for [O {III}] emitters L*(z = 0.3) = 7.3 × 1041 erg s-1 increases by a factor of 3.5 ± 0.4 from z = 0.3 to 0.8.

  11. Global Positioning System III (GPS III)

    DTIC Science & Technology

    2013-12-01

    Global Positioning System III ( GPS III) As of FY 2015 President’s Budget...00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE Global Positioning System III ( GPS III) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...Responsible Office References Program Name Global Positioning System III ( GPS III) DoD Component Air Force

  12. Star formation properties in barred galaxies. III. Statistical study of bar-driven secular evolution using a sample of nearby barred spirals

    SciTech Connect

    Zhou, Zhi-Min; Wu, Hong; Cao, Chen E-mail: hwu@bao.ac.cn

    2015-01-01

    Stellar bars are important internal drivers of secular evolution in disk galaxies. Using a sample of nearby spiral galaxies with weak and strong bars, we explore the relationships between the star formation feature and stellar bars in galaxies. We find that galaxies with weak bars tend coincide with low concentrical star formation activity, while those with strong bars show a large scatter in the distribution of star formation activity. We find enhanced star formation activity in bulges toward stronger bars, although not predominantly, consistent with previous studies. Our results suggest that different stages of the secular process and many other factors may contribute to the complexity of the secular evolution. In addition, barred galaxies with intense star formation in bars tend to have active star formation in their bulges and disks, and bulges have higher star formation densities than bars and disks, indicating the evolutionary effects of bars. We then derived a possible criterion to quantify the different stages of the bar-driven physical process, while future work is needed because of the uncertainties.

  13. On the evolution of accretion disc flow in cataclysmic variables. III - Outburst properties of constant and uniform-alpha model discs

    NASA Technical Reports Server (NTRS)

    Lin, D. N. C.; Faulkner, J.; Papaloizou, J.

    1985-01-01

    Attention is given to the stability and evolution of some simple accretion disk models in which the viscosity is prescribed by an ad hoc, uniform-alpha model. Emphasis is placed on systems in which the mass input rate from the secondary to the disk around the primary is assumed to be constant, although initial calculations with variable mass input rates are also performed. Time-dependent visual magnitude light curves constructed for cataclysmic binaries with a range of disk size, primary mass and mass input rate, and viscosity magnitude, are compared with the observed properties of various cataclysmic variable subclasses. The results obtained indicate that the observational differences between novae and dwarf novae may be due to mass input rate differences. The present models can reproduce the gross observational features of U-Gem-type dwarf nova outbursts.

  14. Evolution of EF-hand calcium-modulated proteins. III. Exon sequences confirm most dendrograms based on protein sequences: calmodulin dendrograms show significant lack of parallelism

    NASA Technical Reports Server (NTRS)

    Nakayama, S.; Kretsinger, R. H.

    1993-01-01

    In the first report in this series we presented dendrograms based on 152 individual proteins of the EF-hand family. In the second we used sequences from 228 proteins, containing 835 domains, and showed that eight of the 29 subfamilies are congruent and that the EF-hand domains of the remaining 21 subfamilies have diverse evolutionary histories. In this study we have computed dendrograms within and among the EF-hand subfamilies using the encoding DNA sequences. In most instances the dendrograms based on protein and on DNA sequences are very similar. Significant differences between protein and DNA trees for calmodulin remain unexplained. In our fourth report we evaluate the sequences and the distribution of introns within the EF-hand family and conclude that exon shuffling did not play a significant role in its evolution.

  15. Evolution of long-lived globular cluster stars. III. Effect of the initial helium spread on the position of stars in a synthetic Hertzsprung-Russell diagram

    NASA Astrophysics Data System (ADS)

    Chantereau, W.; Charbonnel, C.; Meynet, G.

    2016-08-01

    Context. Globular clusters host multiple populations of long-lived low-mass stars whose origin remains an open question. Several scenarios have been proposed to explain the associated photometric and spectroscopic peculiarities. They differ, for instance, in the maximum helium enrichment they predict for stars of the second population, which these stars can inherit at birth as the result of the internal pollution of the cluster by different types of stars of the first population. Aims: We present the distribution of helium-rich stars in present-day globular clusters as it is expected in the original framework of the fast-rotating massive stars scenario (FRMS) as first-population polluters. We focus on NGC 6752. Methods: We completed a grid of 330 stellar evolution models for globular cluster low-mass stars computed with different initial chemical compositions corresponding to the predictions of the original FRMS scenario for [Fe/H] = -1.75. Starting from the initial helium-sodium relation that allows reproducing the currently observed distribution of sodium in NGC 6752, we deduce the helium distribution expected in that cluster at ages equal to 9 and 13 Gyr. We distinguish the stars that are moderately enriched in helium from those that are very helium-rich (initial helium mass fraction below and above 0.4, respectively), and compare the predictions of the FRMS framework with other scenarios for globular cluster enrichment. Results: The effect of helium enrichment on the stellar lifetime and evolution reduces the total number of very helium-rich stars that remain in the cluster at 9 and 13 Gyr to only 12% and 10%, respectively, from an initial fraction of 21%. Within this age range, most of the stars still burn their hydrogen in their core, which widens the MS band significantly in effective temperature. The fraction of very helium-rich stars drops in the more advanced evolution phases, where the associated spread in effective temperature strongly decreases. These

  16. Welding III.

    ERIC Educational Resources Information Center

    Allegheny County Community Coll., Pittsburgh, PA.

    Instructional objectives and performance requirements are outlined in this course guide for Welding III, an advanced course in arc welding offered at the Community College of Allegheny County to provide students with the proficiency necessary for industrial certification. The course objectives, which are outlined first, specify that students will…

  17. Biochemical upgrading of oils

    DOEpatents

    Premuzic, E.T.; Lin, M.S.

    1999-01-12

    A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed. 121 figs.

  18. Biochemical upgrading of oils

    DOEpatents

    Premuzic, Eugene T.; Lin, Mow S.

    1999-01-12

    A process for biochemical conversion of heavy crude oils is provided. The process includes contacting heavy crude oils with adapted biocatalysts. The resulting upgraded oil shows, a relative increase in saturated hydrocarbons, emulsions and oxygenates and a decrease in compounds containing in organic sulfur, organic nitrogen and trace metals. Adapted microorganisms which have been modified under challenged growth processes are also disclosed.

  19. Biochemical Education in Brazil.

    ERIC Educational Resources Information Center

    Vella, F.

    1988-01-01

    Described are discussions held concerning the problems of biochemical education in Brazil at a meeting of the Sociedade Brazileira de Bioquimica in April 1988. Also discussed are other visits that were made to universities in Brazil. Three major recommendations to improve the state of biochemistry education in Brazil are presented. (CW)

  20. Measures of Biochemical Sociology

    ERIC Educational Resources Information Center

    Snell, Joel; Marsh, Mitchell

    2008-01-01

    In a previous article, the authors introduced a new sub field in sociology that we labeled "biochemical sociology." We introduced the definition of a sociology that encompasses sociological measures, psychological measures, and biological indicators Snell & Marsh (2003). In this article, we want to demonstrate a research strategy that would assess…

  1. Nanoparticles as biochemical sensors

    PubMed Central

    El-Ansary, Afaf; Faddah, Layla M

    2010-01-01

    There is little doubt that nanoparticles offer real and new opportunities in many fields, such as biomedicine and materials science. Such particles are small enough to enter almost all areas of the body, including cells and organelles, potentially leading to new approaches in nanomedicine. Sensors for small molecules of biochemical interest are of critical importance. This review is an attempt to trace the use of nanomaterials in biochemical sensor design. The possibility of using nanoparticles functionalized with antibodies as markers for proteins will be elucidated. Moreover, capabilities and applications for nanoparticles based on gold, silver, magnetic, and semiconductor materials (quantum dots), used in optical (absorbance, luminescence, surface enhanced Raman spectroscopy, surface plasmon resonance), electrochemical, and mass-sensitive sensors will be highlighted. The unique ability of nanosensors to improve the analysis of biochemical fluids is discussed either through considering the use of nanoparticles for in vitro molecular diagnosis, or in the biological/biochemical analysis for in vivo interaction with the human body. PMID:24198472

  2. Tidal evolution of the Uranian satellites. III - Evolution through the Miranda-Umbriel 3:1, Miranda-Ariel 5:3, and Ariel-Umbriel 2:1 mean-motion commensurabilities

    NASA Technical Reports Server (NTRS)

    Tittemore, William C.; Wisdom, Jack

    1990-01-01

    Numerical experiments have been conducted which indicate that the orbital eccentricity of Miranda may have reached a value sufficiently large to have affected its thermal evolution. There is a large chaotic zone associated with the Miranda-Ariel 5:3 mean-motion commensurability, even in the planar approximation; the orbital eccentricities of both satellites may vary chaotically for a considerable period. Since the anomalously high orbital inclination of Miranda is a consequence of passage through the 3:1 commensurability with Umbriel, the requirement that the satellites encountered this resonance places a lower limit on the Uranian specific dissipation function of 39,000.

  3. Variations on a theme - the evolution of hydrocarbon solids. III. Size-dependent properties - the optEC(s)(a) model

    NASA Astrophysics Data System (ADS)

    Jones, A. P.

    2012-06-01

    Context. The properties of hydrogenated amorphous carbon (a-C:H) dust evolve in response to the local radiation field in the interstellar medium (ISM) and the evolution of these properties is particularly dependent upon the particle size. Aims: A model for finite-sized, low-temperature amorphous hydrocarbon particles, based on the microphysical properties of random and defected networks of carbon and hydrogen atoms, with surfaces passivated by hydrogen atoms, has been developed. Methods: The eRCN/DG and the optEC(s) models have been combined, adapted and extended into a new optEC(s)(a) model that is used to calculate the optical properties of hydrocarbon grain materials down into the sub-nanometre size regime, where the particles contain only a few tens of carbon atoms. Results: The optEC(s)(a) model predicts a continuity in properties from large to small (sub-nm) carbonaceous grains. Tabulated data of the size-dependent optical constants (from EUV to cm wavelengths) for a-C:H (nano-)particles as a function of the bulk material band gap [Eg(bulk)], or equivalently the hydrogen content, are provided. The effective band gap [Eg(eff.)] is found to be significantly larger than Eg(bulk) for hydrogen-poor a-C(:H) nano-particles and their predicted long-wavelength (λ > 30 μm) optical properties differ from those derived for interstellar polycyclic aromatic hydrocarbons (PAHs). Conclusions: The optEC(s)(a) model is used to investigate the size-dependent structural and spectral evolution of a-C(:H) materials under ISM conditions, including: the IR-FUV extinction, the 217 nm bump and the infrared emission bands. The model makes several predictions that can be tested against observations. Appendices A-E are available in electronic from at http://www.aanda.orgData files are only available form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/542/A98

  4. Formation and evolution of early-type galaxies - III. Dependence of the star formation history on the total mass and initial overdensity

    NASA Astrophysics Data System (ADS)

    Merlin, E.; Chiosi, C.; Piovan, L.; Grassi, T.; Buonomo, U.; Barbera, F. La

    2012-12-01

    We investigate the influence of the initial overdensities and masses of proto-galaxies on their subsequent evolution (the star formation history in particular) to understand whether these key parameters are sufficient to account for the varied properties of the galactic populations. By means of fully hydrodynamical N-body simulations performed with the code EVOL, we produce 12 self-similar models of early-type galaxies of different initial masses and overdensities, and follow their evolution from the early epochs (detachment from the linear regime and Hubble flow at z ≥ 20) down to the stage when mass assembly is complete, i.e. z ≤ 1 (in some cases the models are calculated up to z = 0). The simulations include radiative cooling, star formation, stellar energy feedback, re-ionizing photo-heating background and chemical enrichment of the interstellar medium; we do not consider the possible presence of active nuclei. We find a strong correlation between the initial properties of the proto-haloes and their subsequent star formation histories. Massive (Mtot ≃ 1013 M⊙) haloes experience a single, intense burst of star formation (with rates ≥103 M⊙ yr-1) at early epochs, consistently with observations, with less pronounced dependence on the initial overdensity; intermediate-mass (Mtot ≃ 1011 M⊙) haloes have histories that strongly depend on their initial overdensity, whereas low-mass haloes (Mtot ≃ 109 M⊙) always have erratic, bursting like star-forming histories, due to the 'galactic breathing' phenomenon. The model galaxies have morphological, structural and chemical properties resembling those of real galaxies, even though some disagreement still occurs, likely a consequence of some numerical choices. We conclude that total mass and initial overdensity drive the star formation histories of early-type galaxies. The model galaxies belong to the so-called quasi-monolithic (or early hierarchical) scenario in the sense that the aggregation of lumps of

  5. Biochemical and Structural Properties of Mouse Kynurenine Aminotransferase III▿

    PubMed Central

    Han, Qian; Robinson, Howard; Cai, Tao; Tagle, Danilo A.; Li, Jianyong

    2009-01-01

    Kynurenine aminotransferase III (KAT III) has been considered to be involved in the production of mammalian brain kynurenic acid (KYNA), which plays an important role in protecting neurons from overstimulation by excitatory neurotransmitters. The enzyme was identified based on its high sequence identity with mammalian KAT I, but its activity toward kynurenine and its structural characteristics have not been established. In this study, the biochemical and structural properties of mouse KAT III (mKAT III) were determined. Specifically, mKAT III cDNA was amplified from a mouse brain cDNA library, and its recombinant protein was expressed in an insect cell protein expression system. We established that mKAT III is able to efficiently catalyze the transamination of kynurenine to KYNA and has optimum activity at relatively basic conditions of around pH 9.0 and at relatively high temperatures of 50 to 60°C. In addition, mKAT III is active toward a number of other amino acids. Its activity toward kynurenine is significantly decreased in the presence of methionine, histidine, glutamine, leucine, cysteine, and 3-hydroxykynurenine. Through macromolecular crystallography, we determined the mKAT III crystal structure and its structures in complex with kynurenine and glutamine. Structural analysis revealed the overall architecture of mKAT III and its cofactor binding site and active center residues. This is the first report concerning the biochemical characteristics and crystal structures of KAT III enzymes and provides a basis toward understanding the overall physiological role of mammalian KAT III in vivo and insight into regulating the levels of endogenous KYNA through modulation of the enzyme in the mouse brain. PMID:19029248

  6. Biochemical Analyses of Dissimilatory Iron Reduction by Shewanella oneidensis

    NASA Astrophysics Data System (ADS)

    Ruebush, S. S.; Tien, M.; Icopini, G. A.; Brantley, S. L.

    2002-12-01

    Shewanella oneidensis demonstrates respiratory flexibility by the transfer of electrons to Fe (III) and Mn (IV) oxides under anaerobic conditions. Researchers postulate that the bacterium utilizes surface proteins to facilitate the respiratory mechanism for dissimilatory iron(III) reduction. Previous genetic and biochemical studies has shown that iron reduction is associated with the outer membrane of the cell. The identity of the terminal reductase is not yet known. S. oneidensis has been shown to use soluble extra-cellular compounds to facilitate iron(III) reduction as well as expression of novel proteins on the cell surface when interacting with iron(III) oxides. Our results show that the outer membrane fraction possess enzymatic activity for converting Fe(III) to Fe(II) as measured by ferrozine complexation. AQDS, extra-cellular organic extracts, and iron(III) both soluble and solid have been assayed for activity with outer membrane fractions. Zymograms of the membrane fractions separated by isoelectric focusing and native PAGE electrophoresis stained using ferrozine have implicated proteins that are directly involved in the Fe(III) reduction process. A proteomics analysis of outer membrane proteins has also been implemented to identify different expression patterns under Fe(III) reducing conditions. Proteins that are unique to Fe(III) reduction have been isolated and identified using N-terminal sequence analysis. We will also attempt to examine the effect of enzymatic iron(III) reduction on isotopic partitioning from in vitro assays.

  7. Associative learning in biochemical networks.

    PubMed

    Gandhi, Nikhil; Ashkenasy, Gonen; Tannenbaum, Emmanuel

    2007-11-07

    It has been recently suggested that there are likely generic features characterizing the emergence of systems constructed from the self-organization of self-replicating agents acting under one or more selection pressures. Therefore, structures and behaviors at one length scale may be used to infer analogous structures and behaviors at other length scales. Motivated by this suggestion, we seek to characterize various "animate" behaviors in biochemical networks, and the influence that these behaviors have on genomic evolution. Specifically, in this paper, we develop a simple, chemostat-based model illustrating how a process analogous to associative learning can occur in a biochemical network. Associative learning is a form of learning whereby a system "learns" to associate two stimuli with one another. Associative learning, also known as conditioning, is believed to be a powerful learning process at work in the brain (associative learning is essentially "learning by analogy"). In our model, two types of replicating molecules, denoted as A and B, are present in some initial concentration in the chemostat. Molecules A and B are stimulated to replicate by some growth factors, denoted as G(A) and G(B), respectively. It is also assumed that A and B can covalently link, and that the conjugated molecule can be stimulated by either the G(A) or G(B) growth factors (and can be degraded). We show that, if the chemostat is stimulated by both growth factors for a certain time, followed by a time gap during which the chemostat is not stimulated at all, and if the chemostat is then stimulated again by only one of the growth factors, then there will be a transient increase in the number of molecules activated by the other growth factor. Therefore, the chemostat bears the imprint of earlier, simultaneous stimulation with both growth factors, which is indicative of associative learning. It is interesting to note that the dynamics of our model is consistent with certain aspects of

  8. EVOLUTION, NUCLEOSYNTHESIS, AND YIELDS OF AGB STARS AT DIFFERENT METALLICITIES. III. INTERMEDIATE-MASS MODELS, REVISED LOW-MASS MODELS, AND THE pH-FRUITY INTERFACE

    SciTech Connect

    Cristallo, S.; Straniero, O.; Piersanti, L.; Gobrecht, D.

    2015-08-15

    We present a new set of models for intermediate-mass asymptotic giant branch (AGB) stars (4.0, 5.0, and 6.0 M{sub ⊙}) at different metallicities (−2.15 ≤ [Fe/H] ≤ +0.15). This set integrates the existing models for low-mass AGB stars (1.3 ≤ M/M{sub ⊙} ≤ 3.0) already included in the FRUITY database. We describe the physical and chemical evolution of the computed models from the main sequence up to the end of the AGB phase. Due to less efficient third dredge up episodes, models with large core masses show modest surface enhancements. This effect is due to the fact that the interpulse phases are short and, therefore, thermal pulses (TPs) are weak. Moreover, the high temperature at the base of the convective envelope prevents it from deeply penetrating the underlying radiative layers. Depending on the initial stellar mass, the heavy element nucleosynthesis is dominated by different neutron sources. In particular, the s-process distributions of the more massive models are dominated by the {sup 22}Ne(α,n){sup 25}Mg reaction, which is efficiently activated during TPs. At low metallicities, our models undergo hot bottom burning and hot third dredge up. We compare our theoretical final core masses to available white dwarf observations. Moreover, we quantify the influence intermediate-mass models have on the carbon star luminosity function. Finally, we present the upgrade of the FRUITY web interface, which now also includes the physical quantities of the TP-AGB phase for all of the models included in the database (ph-FRUITY)

  9. Evolution, Nucleosynthesis, and Yields of AGB Stars at Different Metallicities. III. Intermediate-mass Models, Revised Low-mass Models, and the ph-FRUITY Interface

    NASA Astrophysics Data System (ADS)

    Cristallo, S.; Straniero, O.; Piersanti, L.; Gobrecht, D.

    2015-08-01

    We present a new set of models for intermediate-mass asymptotic giant branch (AGB) stars (4.0, 5.0, and 6.0 M⊙) at different metallicities (-2.15 ≤ [Fe/H] ≤ +0.15). This set integrates the existing models for low-mass AGB stars (1.3 ≤ M/M⊙ ≤ 3.0) already included in the FRUITY database. We describe the physical and chemical evolution of the computed models from the main sequence up to the end of the AGB phase. Due to less efficient third dredge up episodes, models with large core masses show modest surface enhancements. This effect is due to the fact that the interpulse phases are short and, therefore, thermal pulses (TPs) are weak. Moreover, the high temperature at the base of the convective envelope prevents it from deeply penetrating the underlying radiative layers. Depending on the initial stellar mass, the heavy element nucleosynthesis is dominated by different neutron sources. In particular, the s-process distributions of the more massive models are dominated by the 22Ne(α,n)25Mg reaction, which is efficiently activated during TPs. At low metallicities, our models undergo hot bottom burning and hot third dredge up. We compare our theoretical final core masses to available white dwarf observations. Moreover, we quantify the influence intermediate-mass models have on the carbon star luminosity function. Finally, we present the upgrade of the FRUITY web interface, which now also includes the physical quantities of the TP-AGB phase for all of the models included in the database (ph-FRUITY).

  10. ON THE CLUSTER PHYSICS OF SUNYAEV-ZEL'DOVICH AND X-RAY SURVEYS. III. MEASUREMENT BIASES AND COSMOLOGICAL EVOLUTION OF GAS AND STELLAR MASS FRACTIONS

    SciTech Connect

    Battaglia, N.; Bond, J. R.; Pfrommer, C.; Sievers, J. L.

    2013-11-10

    Gas masses tightly correlate with the virial masses of galaxy clusters, allowing for a precise determination of cosmological parameters by means of X-ray surveys. However, the gas mass fractions (f{sub gas}) at the virial radius (R{sub 200}) derived from recent Suzaku observations are considerably larger than the cosmic mean, calling into question the accuracy of cosmological parameters. Here, we use a large suite of cosmological hydrodynamical simulations to study measurement biases of f{sub gas}. We employ different variants of simulated physics, including radiative gas physics, star formation, and thermal feedback by active galactic nuclei, which we show is able to arrest overcooling and to result in constant stellar mass fractions for redshifts z < 1. Computing the mass profiles in 48 angular cones, we find anisotropic gas and total mass distributions that imply an angular variance of f{sub gas} at the level of 30%. This anisotropy originates from the recent formation epoch of clusters and from the strong internal baryon-to-dark-matter density bias. In the most extreme cones, f{sub gas} can be biased high by a factor of two at R{sub 200} in massive clusters (M{sub 200} ∼ 10{sup 15} M{sub ☉}), thereby providing an explanation for high f{sub gas} measurements by Suzaku. While projection lowers this factor, there are other measurement biases that may (partially) compensate. At R{sub 200}, f{sub gas} is biased high by 20% when assuming hydrostatic equilibrium masses, i.e., neglecting the kinetic pressure, and by another ∼10%-20% due to the presence of density clumping. At larger radii, both measurement biases increase dramatically. While the cluster sample variance of the true f{sub gas} decreases to a level of 5% at R{sub 200}, the sample variance that includes both measurement biases remains fairly constant at the level of 10%-20%. The constant redshift evolution of f{sub gas} within R{sub 500} for massive clusters is encouraging for using gas masses to

  11. Mass and environment as drivers of galaxy evolution. III. The constancy of the faint-end slope and the merging of galaxies

    SciTech Connect

    Peng, Ying-jie; Lilly, Simon J.; Carollo, Marcella; Renzini, Alvio

    2014-08-01

    Using our continuity approach, we explore the underlying connections between the evolution of the faint-end slope α{sub s} of the stellar mass function of star-forming galaxies, the logarithmic slope β of the specific star formation rate (sSFR)-mass relation, and the merging of galaxies. We derive analytically the consequences of the observed constancy of α{sub s} since redshifts of at least z ∼ 2. If the logarithmic slope β of the sSFR-mass relation is negative, then the faint-end slope α{sub s} should quickly diverge due to the differential mass increase of galaxies on the star-forming main sequence, and this will also quickly destroy the Schechter form of the mass function. This problem can be solved by removing low-mass galaxies by merging them into more massive galaxies. We quantify this process by introducing the specific merger mass rate (sMMR) as the specific rate of mass added to a given galaxy through mergers. For a modest negative value of β ∼ –0.1, an average sMMR ∼ 0.1 sSFR across the population is required to keep α{sub s} constant with epoch, as observed. This in turn implies a merger rate of ∼0.2 sSFR for major mergers, which is consistent with the available observational estimates. More negative values of β require higher sMMR and higher merger rates, and the steepening of the mass function becomes impossible to control for β < –(α{sub s} + 2). The close link that is required between the in situ sSFR and the sMMR probably arises because both are closely linked to the buildup of dark matter halos. These new findings further develop the formalism for the evolving galaxy population that we introduced earlier and show how striking symmetries in the galaxy population can emerge as the result of deep links between the physical processes involved.

  12. THE M31 VELOCITY VECTOR. III. FUTURE MILKY WAY M31-M33 ORBITAL EVOLUTION, MERGING, AND FATE OF THE SUN

    SciTech Connect

    Van der Marel, Roeland P.; Sohn, Sangmo Tony; Anderson, Jay; Besla, Gurtina; Cox, T. J.

    2012-07-01

    We study the future orbital evolution and merging of the Milky Way (MW)-M31-M33 system, using a combination of collisionless N-body simulations and semi-analytic orbit integrations. Monte Carlo simulations are used to explore the consequences of varying all relevant initial phase-space and mass parameters within their observational uncertainties. The observed M31 transverse velocity from Papers I and II implies that the MW and M31 will merge t = 5.86{sup +1.61}{sub -0.72} Gyr from now. The first pericenter occurs at t = 3.87{sup +0.42}{sub -0.32} Gyr, at a pericenter distance of r = 31.0{sup +38.0}{sub -19.8} kpc. In 41% of Monte Carlo orbits, M31 makes a direct hit with the MW, defined here as a first-pericenter distance less than 25 kpc. For the M31-M33 system, the first-pericenter time and distance are t = 0.85{sup +0.18}{sub -0.13} Gyr and r = 80.8{sup +42.2}{sub -31.7} kpc. By the time M31 gets to its first pericenter with the MW, M33 is close to its second pericenter with M31. For the MW-M33 system, the first-pericenter time and distance are t = 3.70{sup +0.74}{sub -0.46} Gyr and r = 176.0{sup +239.0}{sub -136.9} kpc. The most likely outcome is for the MW and M31 to merge first, with M33 settling onto an orbit around them that may decay toward a merger later. However, there is a 9% probability that M33 makes a direct hit with the MW at its first pericenter, before M31 gets to or collides with the MW. Also, there is a 7% probability that M33 gets ejected from the Local Group, temporarily or permanently. The radial mass profile of the MW-M31 merger remnant is significantly more extended than the original profiles of either the MW or M31, and suggests that the merger remnant will resemble an elliptical galaxy. The Sun will most likely ({approx}85% probability) end up at a larger radius from the center of the MW-M31 merger remnant than its current distance from the MW center, possibly further than 50 kpc ({approx}10% probability). There is a {approx}20

  13. Photo-catalyzed surface hydrolysis of iridium(iii) ions on semiconductors: a facile method for the preparation of semiconductor/IrOx composite photoanodes toward oxygen evolution reaction.

    PubMed

    Wu, Qingyong; Xu, Di; Xue, Ning; Liu, Tengyi; Xiang, Min; Diao, Peng

    2016-12-21

    We previously reported that the hydrolysis of Ir(3+) in homogeneous solution could be triggered by irradiation with light whose energy was larger than a threshold value. In this work, we demonstrated that, by introducing Fe2O3 particles into solution, the incident light energy-restriction for the photo-catalyzed hydrolysis could be broken and the hydrolysis occurred at the Fe2O3/solution interface. The photo-generated holes on the Fe2O3 surface played a key role in oxidizing Ir(iii) to Ir(iv) species and triggered the deposition of IrOx. We showed that this photo-catalyzed surface hydrolysis is a universal phenomenon that takes place on the surface of many n-type semiconductors such as Fe2O3, TiO2, and Ag3PO4. As IrOx is an efficient catalyst for oxygen evolution reaction, surface hydrolysis is a general, facile and efficient strategy to prepare semiconductor/IrOx composites, which can be used as anodic materials for photoelectrochemical water splitting.

  14. Misleading biochemical laboratory test results

    PubMed Central

    Nanji, Amin A.

    1984-01-01

    This article reviews the general and specific factors that interfere with the performance of common biochemical laboratory tests and the interpretation of their results. The clinical status of the patient, drug interactions, and in-vivo and in-vitro biochemical interactions and changes may alter the results obtained from biochemical analysis of blood constituents. Failure to recognize invalid laboratory test results may lead to injudicious and dangerous management of patients. PMID:6375845

  15. Biochemical Reversal of Aging

    NASA Astrophysics Data System (ADS)

    Ely, John T. A.

    2006-03-01

    We cite our progress on biochemical reversal of aging. However, it may be circa 2 years before we have necessary substances at low cost. Meanwhile, without them, a number of measures can be adopted providing marked improvement for the problems of aging in modern societies. For example, enzymes are needed to excrete toxins that accelerate aging; Hg is the ultimate toxin that disables all enzymes (including those needed to excrete Hg itself). Low Hg level in the urine, due to loss of excretory ability, causes the diagnosis of Hg toxicity to almost always be missed. Hg sources must be removed from the body! Another example is excess sugar; hyperglycemia decreases intracellular ascorbic acid (AA) by competitively inhibiting the insulin- mediated active transport of AA into cells. Thus, immunity is impaired by low leucocyte AA. AA is needed for new proteins in aging tissues. Humans must supplement AA; their need same as in AA-synthesizing mammals.

  16. Rapamycin regulates biochemical metabolites

    PubMed Central

    Tucci, Paola; Porta, Giovanni; Agostini, Massimiliano; Antonov, Alexey; Garabadgiu, Alexander Vasilievich; Melino, Gerry; Willis, Anne E

    2013-01-01

    The mammalian target of rapamycin (mTOR) kinase is a master regulator of protein synthesis that couples nutrient sensing to cell growth, and deregulation of this pathway is associated with tumorigenesis. p53, and its less investigated family member p73, have been shown to interact closely with mTOR pathways through the transcriptional regulation of different target genes. To investigate the metabolic changes that occur upon inhibition of the mTOR pathway and the role of p73 in this response primary mouse embryonic fibroblast from control and TAp73−/− were treated with the macrocyclic lactone rapamycin. Extensive gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS/MS) analysis were used to obtain a rapamycin-dependent global metabolome profile from control or TAp73−/− cells. In total 289 metabolites involved in selective pathways were identified; 39 biochemical metabolites were found to be significantly altered, many of which are known to be associated with the cellular stress response. PMID:23839040

  17. Ribonuclease revisited: structural insights into ribonuclease III family enzymes.

    PubMed

    MacRae, Ian J; Doudna, Jennifer A

    2007-02-01

    Ribonuclease III (RNase III) enzymes occur ubiquitously in biology and are responsible for processing RNA precursors into functional RNAs that participate in protein synthesis, RNA interference and a range of other cellular activities. Members of the RNase III enzyme family, including Escherichia coli RNase III, Rnt1, Dicer and Drosha, share the ability to recognize and cleave double-stranded RNA (dsRNA), typically at specific positions or sequences. Recent biochemical and structural data have shed new light on how RNase III enzymes catalyze dsRNA hydrolysis and how substrate specificity is achieved. A major theme emerging from these studies is that accessory domains present in different RNase III enzymes are the key determinants of substrate selectivity, which in turn dictates the specialized biological function of each type of RNase III protein.

  18. Unquiet Evolution: Consideration of a Previous Synthesis

    ERIC Educational Resources Information Center

    Angseesing, J. P. A.

    1972-01-01

    Presents genetical and biochemical data to show that the conclusion presented by Dyer (EJ 036 108) is by no meas settled. Evidence to support the concept: evolution by selectively neutral polymorphisms is inconclusive. (AL)

  19. Structure of a Eukaryotic RNase III Post-Cleavage Complex Reveals a Double- Ruler Mechanism for Substrate Selection

    PubMed Central

    Liang, Yu-He; Lavoie, Mathieu; Comeau, Marc-Andre; Elela, Sherif Abou; Ji, Xinhua

    2014-01-01

    SUMMARY RNase III represents a family of dsRNA-specific endoribonucleases required for RNA maturation and gene regulation. The mechanism of action has been well characterized for the bacterial enzyme, but is not clear for eukaryotic RNase IIIs. Here, we describe the structure of Saccharomyces cerevisiae RNase III (Rnt1p) post-cleavage complex and explain the basis of its affinity for RNA stems capped with an NGNN tetraloop. The structure shows specific interactions between a new structural motif located at the end of Rnt1p dsRNA-binding domain (dsRBD) and the guanine nucleotide in the second position of the loop. Strikingly, structural and biochemical analyses indicate that the dsRBD and N-terminal domain function as two rulers measuring the distance between the tetraloop and the cleavage site. This unusual mechanism of substrate selectivity represents an example of the evolution of substrate selectivity and provides a framework for understanding the mechanism of action of eukaryotic RNase IIIs. PMID:24703949

  20. [Napoleon III's urogenital disease (1808-1873)].

    PubMed

    Androutsos, G

    2000-02-01

    We tried through this paper to reconstitute the evolution of the urologic illness of Napoleon III, last emperor of France, the first symptoms of which appeared many years before the fatal war of 1870, which led to the dismembering of France. In this connection, we present Napoleon III's physicians and his cures, along with the diagnostic and therapeutic errors. The case of Napoleon III is a typical example of the influence the bad health of a sovereign can exercise on the destiny of his country.

  1. The role of thermodynamics in biochemical engineering

    NASA Astrophysics Data System (ADS)

    von Stockar, Urs

    2013-09-01

    This article is an adapted version of the introductory chapter of a book whose publication is imminent. It bears the title "Biothermodynamics - The role of thermodynamics in biochemical engineering." The aim of the paper is to give a very short overview of the state of biothermodynamics in an engineering context as reflected in this book. Seen from this perspective, biothermodynamics may be subdivided according to the scale used to formalize the description of the biological system into three large areas: (i) biomolecular thermodynamics (most fundamental scale), (ii) thermodynamics of metabolism (intermediary scale), and (iii) whole-cell thermodynamics ("black-box" description of living entities). In each of these subareas, the main available theoretical approaches and the current and the potential applications are discussed. Biomolecular thermodynamics (i) is especially well developed and is obviously highly pertinent for the development of downstream processing. Its use ought to be encouraged as much as possible. The subarea of thermodynamics of live cells (iii), although scarcely applied in practice, is also expected to enhance bioprocess research and development, particularly in predicting culture performances, for understanding the driving forces for cellular growth, and in developing, monitoring, and controlling cellular cultures. Finally, there is no question that thermodynamic analysis of cellular metabolism (ii) is a promising tool for systems biology and for many other applications, but quite a large research effort is still needed before it may be put to practical use.

  2. Biochemical Engineering and Industrial Biotechnology.

    ERIC Educational Resources Information Center

    Moo-Young, Murray

    1986-01-01

    Describes the biochemical engineering and industrial biotechnology programs of the University of Waterloo (Ontario, Canada). Provides descriptions of graduate courses, along with a sample of current research activities. Includes a discussion of the programs' mechanisms for technology transfer. (TW)

  3. A Course in... Biochemical Engineering.

    ERIC Educational Resources Information Center

    Ng, Terry K-L.; And Others

    1988-01-01

    Describes a chemical engineering course for senior undergraduates and first year graduate students in biochemical engineering. Discusses five experiments used in the course: aseptic techniques, dissolved oxygen measurement, oxygen uptake by yeast, continuous sterilization, and cultivation of microorganisms. (MVL)

  4. Hydrophobic hydrophilic phenomena in biochemical processes.

    PubMed

    Ben-Naim, Arieh

    2003-09-01

    The evolution of concepts developed in the study of the hydrophobic affect is surveyed, within the more general context of solvent-induced effects. A systematic analysis of the solvent-induced contribution to the driving force for the process of protein folding has led to two important modifications in our understanding of these effects. First, the conventional concepts of hydrophobic solvation and hydrophobic interactions had to be replaced by their respective conditional effects. Second, each of the hydrophobic effects has also a corresponding hydrophilic counterpart. Some of the latter effects could contribute significantly to the total driving force for the process of protein folding, and perhaps even dominate the driving force for biochemical processes.

  5. Divergent Evolution of the repFII Replicon of IncF Plasmids Carrying Cytotoxic Necrotizing Factor cnf2, Cytolethal Distending Toxin cdtIII, and f17Ae Fimbrial Variant Genes in Type 2 Necrotoxigenic Escherichia coli Isolates from Calves

    PubMed Central

    Bihannic, Morgan; Haenni, Marisa; Oswald, Eric

    2015-01-01

    Among the pathovars of Escherichia coli in cattle, necrotoxigenic E. coli (NTEC) is defined by the production of cytotoxic necrotizing factors (CNFs). In particular, type 2 NTEC (NTEC2) strains are frequent in diarrheic and septicemic calves and usually coproduce CNF type 2 (CNF2), cytolethal distending toxin type III (CDTIII), and fimbrial adhesins of the F17 family, whose genetic determinants have frequently been reported on the same Vir-like plasmid. In this study, we investigated the genetic environment of the cnf2, f17Ae, and cdtIII genes in a collection of fecal E. coli isolates recovered from 484 French and 58 Iranian calves. In particular, we highlighted the spread of cnf2, f17Ae, and cdtIII on similar 150-kb IncF plasmids harboring the newly assigned repFII replicon allele F74 in NTEC2 isolates. Interestingly, this 150-kb IncF plasmid differed from the 140-kb IncF plasmid harboring the newly assigned repFII replicon allele F75 and carrying cnf2 alone. These results suggest two divergent lineages of cnf2-carrying IncF plasmids depending on the presence of the f17Ae and cdtIII genes. This partition was observed in E. coli strains of unrelated backgrounds, suggesting two different evolutionary paths of cnf2-carrying IncF plasmids rather than divergent evolutions of NTEC2 clones. The driving forces for such divergent evolutions are not known, and further studies are required to clarify the selection of plasmid subtypes spreading virulence determinants in E. coli, in particular, plasmids of the IncF family. PMID:26546422

  6. Effects of Mad Honey on Some Biochemical Parameters in Rats.

    PubMed

    Sahin, Huseyin; Yildiz, Oktay; Kolayli, Sevgi

    2016-10-01

    The aims of this study were to determine grayanotoxin (GTX-III) toxin level in mad honey using liquid chromatography-tandem mass spectrometry and examine the dynamic changes of certain biochemical parameters in blood serum of rats that consumed mad honey. For the experimental animal study, 20 Sprague-Dawley female rats were divided into 5 groups of 4 rats each, with one group being the control group (Group 1) and the others being the experimental groups (Groups 2-5). Groups 2, 3, 4, and 5 were, respectively, given mad honey extract at doses of 0.3, 0.6, 1.2, and 2.4 mg/g body weight/day via oral gavage for 8 days. According to results, the quantity of GTX-III found in the honey sample as 39.949 ± 0.020 μg GTX-III/g honey, and the biochemical analysis of the tested parameters (aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, creatine kinase, and creatine kinase muscle and brain) showed a significant elevation with increasing concentration of honey. In conclusion, the use of increasing concentrations of Rhododendron honey was seen as a source of enzymatic symptoms.

  7. Biochemical Control of Marine Fouling

    DTIC Science & Technology

    1988-01-14

    amino acid and catecholamine analyses by ion-exchange chromatography, and determination with ninhydrin , performed in collaboration with Dr. Herbert...attempted to design and test new, potentially specific (nonhazardous, environmentally safe) biochemical inhibitors of the recruitment and fouling...reaction- sequences. In this effort, we have concentrated first on the design and testing of agents which specifically block the larval receptors and

  8. Global Positioning System III (GPS III)

    DTIC Science & Technology

    2015-12-01

    from the SV Bus, specifically the Scalable Power Regulation Unit and is being amplified by the solar arrays which act as highly efficient antennas. To...Military Operations in Urban Terrain; Defense-Wide Mission Support; Air Mobility; and Space Launch Orbital Support. For military users, the GPS III...Service: The GPS III program will provide O&S for on- orbit support through the Launch and On- Orbit Support contract. For Space Vehicle (SV)01 and

  9. Interferometric biochemical and chemical sensors

    NASA Astrophysics Data System (ADS)

    Gauglitz, Guenter; Brecht, Andreas; Kraus, Gerolf

    1995-09-01

    Interferometric principles have gained wide acceptance in the field of chemical and biochemical sensing. Reflectometric interference spectrometry sensors using white light multiple reflections at thin layers, structures of polymers, or monolayers of biochemicals are discussed in a survey. These are compared to other techniques, especially methods using surface plasmon resonance and grating couplers. Applications in the area of environmental monitoring in public safety are given, demonstrating the results for halogenated hydrocarbons in air and water as well as pesticides in ground water. Calibration curves, limits of decision, of detection, and of determination are specified and discussed with respect to EU limits. The application of multivariate data analysis is considered including artificial neuronal networks for multisensor systems and referencing in the case of gas sensors.

  10. Metabolism. Part III: Lipids.

    ERIC Educational Resources Information Center

    Bodner, George M.

    1986-01-01

    Describes the metabolic processes of complex lipids, including saponification, activation and transport, and the beta-oxidation spiral. Discusses fatty acid degradation in regard to biochemical energy and ketone bodies. (TW)

  11. An Integrated Qualitative and Quantitative Biochemical Model Learning Framework Using Evolutionary Strategy and Simulated Annealing.

    PubMed

    Wu, Zujian; Pang, Wei; Coghill, George M

    Both qualitative and quantitative model learning frameworks for biochemical systems have been studied in computational systems biology. In this research, after introducing two forms of pre-defined component patterns to represent biochemical models, we propose an integrative qualitative and quantitative modelling framework for inferring biochemical systems. In the proposed framework, interactions between reactants in the candidate models for a target biochemical system are evolved and eventually identified by the application of a qualitative model learning approach with an evolution strategy. Kinetic rates of the models generated from qualitative model learning are then further optimised by employing a quantitative approach with simulated annealing. Experimental results indicate that our proposed integrative framework is feasible to learn the relationships between biochemical reactants qualitatively and to make the model replicate the behaviours of the target system by optimising the kinetic rates quantitatively. Moreover, potential reactants of a target biochemical system can be discovered by hypothesising complex reactants in the synthetic models. Based on the biochemical models learned from the proposed framework, biologists can further perform experimental study in wet laboratory. In this way, natural biochemical systems can be better understood.

  12. Biochemical characterization of a pedigree with mitochondrially inherited deafness.

    PubMed

    Prezant, R T; Shohat, M; Jaber, L; Pressman, S; Fischel-Ghodsian, N

    1992-11-01

    A large kindred with a predicted 2-locus inheritance of sensorineural deafness, caused by the combination of a mitochondrial and an autosomal recessive mutation, was examined at the biochemical level. Because of the mitochondrial inheritance of this disease, we looked for defects in the oxidative phosphorylation Complexes I, III, IV, and V, the 4 enzymes that include all of the 13 mitochondrially encoded polypeptides. Biosynthetic labelling of lymphoblastoid cells from deaf patients, unaffected siblings, and an unrelated control showed no difference in size, abundance, rate of synthesis, or chloramphenicol-sensitivity of the mitochondrially encoded subunits. Since overall mitochondrial protein synthesis appears normal, these results suggest that the mitochondrial mutation is unlikely to be in a tRNA or rRNA gene. No change in enzymatic levels was seen in lymphoblastoid mitochondria of the deaf patients, compared to unaffected sibs and controls, for Complexes I and IV. Both affected and unaffected family members showed an increase in Complex III activity compared to controls, which may reflect the mitochondrial DNA shared by maternal relatives, or be due to other genetic differences. Complex V activity was increased in deaf individuals compared to their unaffected sibs. Since the family members share the presumptive mitochondrial mutation, differences between deaf and unaffected individuals likely reflect the nuclear background and suggest that the autosomal recessive mutation may be related to the increase in Complex V activity. These biochemical studies provide a guide for sequence analysis of the patients' mitochondrial DNA and for linkage studies in this kindred.

  13. Induced biochemical interactions in crude oils

    SciTech Connect

    Premuzic, E.T.; Lin, M.S.

    1996-08-01

    In the evolution of oil from sedimentary to reservoir conditions, the hydrogen to carbon ratios decrease while the oxygen, nitrogen, and sulfur to carbon ratios increase. During this process, the oils become heavier and richer in asphaltenes. In terms of chemical composition, the oils become enriched in resins, asphaltenes, and polar compounds containing the heteroatoms and metals. Over the geological periods of time, the chemical and physical changes have been brought about by chemical, biological (biochemical) and physical (temperature and pressure) means as well as by the catalytic effects of the sedimentary matrices, migration, flooding, and other physical processes. Therefore, different types of oils are the end products of a given set of such interactions which were brought about by multiple and simultaneous physicochemical processes involving electron transfer, free radical, and chemical reactions. A biocatalyst introduced into a reaction mixture of the type produced by such reactions will seek available chemical reaction sites and react at the most favorable ones. The rates and the chemical pathways by which the biocatalytic reactions will proceed will depend on the oil type and the biocatalyst(s). Some of the possible reaction pathways that may occur in such complex mixtures are discussed.

  14. SUPERSTARS III: K-2.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Education, Raleigh.

    SUPERSTARS III is a K-8 program designed as an enrichment opportunity for self-directed learners in mathematics. The basic purpose of SUPERSTARS III is to provide the extra challenge that self-motivated students need in mathematics and to do so in a structured, long-term program that does not impinge on the normal classroom routine or the…

  15. Biochemical structure of Calendula officinalis.

    PubMed

    Korakhashvili, A; Kacharava, T; Kiknavelidze, N

    2007-01-01

    Calendula officinalis is a well known medicinal herb. It is common knowledge that its medicinal properties are conditioned on biologically active complex substances of Carotin (Provitamin A), Stearin, Triterpiniod, Plavonoid, Kumarin, macro and micro compound elements. Because of constant need in raw material of Calendula officinalis, features of its ontogenetic development agro-biological qualities in various eco regions of Georgia were investigated. The data of biologically active compounds, biochemical structure and the maintenance both in flowers and in others parts of plant is presented; the pharmacological activity and importance in medicine was reviewed.

  16. Hyponatraemia: biochemical and clinical perspectives.

    PubMed

    Gill, G; Leese, G

    1998-09-01

    Hyponatraemia is a common bio-chemical abnormality, occurring in about 15% of hospital inpatients. It is often associated with severe illness and relatively poor outcome. Pathophysiologically, hyponatraemia may be spurious, dilutional, depletional or redistributional. Particularly difficult causes and concepts of hyponatraemia are the syndrome of inappropriate antidiuresis and the sick cell syndrome, which are discussed here in detail. Therapy should always be targeted at the underlying disease process. 'Hyponatraemic symptoms' are of doubtful importance, and may be more related to water overload and/or the causative disease, than to hyponatraemia per se. Artificial elevation of plasma sodium by saline infusion carries the risk of induction of osmotic demyelination (central pontine myelinolysis).

  17. Population III Stars Around the Milky Way

    NASA Astrophysics Data System (ADS)

    Komiya, Yutaka; Suda, Takuma; Fujimoto, Masayuki Y.

    2016-03-01

    We explore the possibility of observing Population III (Pop III) stars, born of primordial gas. Pop III stars with masses below 0.8 M⊙ should survive to date though are not yet observed, but the existence of stars with low metallicity as [{{Fe}}/{{H}}]\\lt -5 in the Milky Way halo suggests the surface pollution of Pop III stars with accreted metals from the interstellar gas after birth. In this paper, we investigate the runaway of Pop III stars from their host mini-halos, considering the ejection of secondary members from binary systems when their massive primaries explode as supernovae. These stars save them from surface pollution. By computing the star formation and chemical evolution along with the hierarchical structure formation based on the extended Press-Schechter merger trees, we demonstrate that several hundreds to tens of thousands of low-mass Pop III stars escape from the building blocks of the Milky Way. The second and later generations of extremely metal-poor stars also escaped from the mini-halos. We discuss the spatial distributions of these escaped stars by evaluating the distances between the mini-halos in the branches of merger trees under the spherical collapse model of dark matter halos. It is demonstrated that the escaped stars distribute beyond the stellar halo with a density profile close to the dark matter halo, while Pop III stars are slightly more centrally concentrated. 6%-30% of the escaped stars leave the Milky Way and go out into the intergalactic space. Based on the results, we discuss the feasibility of observing the Pop III stars with the pristine surface abundance.

  18. Constraining the Statistics of Population III Binaries

    NASA Technical Reports Server (NTRS)

    Stacy, Athena; Bromm, Volker

    2012-01-01

    We perform a cosmological simulation in order to model the growth and evolution of Population III (Pop III) stellar systems in a range of host minihalo environments. A Pop III multiple system forms in each of the ten minihaloes, and the overall mass function is top-heavy compared to the currently observed initial mass function in the Milky Way. Using a sink particle to represent each growing protostar, we examine the binary characteristics of the multiple systems, resolving orbits on scales as small as 20 AU. We find a binary fraction of approx. 36, with semi-major axes as large as 3000 AU. The distribution of orbital periods is slightly peaked at approx. < 900 yr, while the distribution of mass ratios is relatively flat. Of all sink particles formed within the ten minihaloes, approx. 50 are lost to mergers with larger sinks, and 50 of the remaining sinks are ejected from their star-forming disks. The large binary fraction may have important implications for Pop III evolution and nucleosynthesis, as well as the final fate of the first stars.

  19. Co(II)1-xCo(0)x/3Mn(III)2x/3S Nanoparticles Supported on B/N-Codoped Mesoporous Nanocarbon as a Bifunctional Electrocatalyst of Oxygen Reduction/Evolution for High-Performance Zinc-Air Batteries.

    PubMed

    Wang, Zilong; Xiao, Shuang; An, Yiming; Long, Xia; Zheng, Xiaoli; Lu, Xihong; Tong, Yexiang; Yang, Shihe

    2016-06-01

    Rechargeable Zn-air battery is an ideal type of energy storage device due to its high energy and power density, high safety, and economic viability. Its large-scale application rests upon the availability of active, durable, low-cost electrocatalysts for the oxygen reduction reaction (ORR) in the discharge process and oxygen evolution reaction (OER) in the charge process. Herein we developed a novel ORR/OER bifunctional electrocatalyst for rechargeable Zn-air batteries based on the codoping and hybridization strategies. The B/N-codoped mesoporous nanocarbon supported Co(II)1-xCo(0)x/3Mn(III)2x/3S nanoparticles exhibit a superior OER performance compared to that of IrO2 catalyst and comparable Zn-air battery performance to that of the Pt-based battery. The rechargeable Zn-air battery shows high discharge peak power density (over 250 mW cm(-2)) and current density (180 mA cm(-2) at 1 V), specific capacity (∼550 mAh g(-1)), small charge-discharge voltage gap of ∼0.72 V at 20 mA cm(-2) and even higher stability than the Pt-based battery. The advanced performance of the bifunctional catalysts highlights the beneficial role of the simultaneous formation of Mn(III) and Co(0) as well as the dispersed hybridization with the codoped nanocarbon support.

  20. Structure-function analyses of plant type III polyketide synthases.

    PubMed

    Weng, Jing-Ke; Noel, Joseph P

    2012-01-01

    Plant type III polyketide synthases (PKSs) form a superfamily of biosynthetic enzymes involved in the production of a plethora of polyketide-derived natural products important for ecological adaptations and the fitness of land plants. Moreover, tremendous interest in bioengineering of type III PKSs to produce high-value compounds is increasing. Compared to type I and type II PKSs, which form either large modular protein complexes or dissociable molecular assemblies, type III PKSs exist as smaller homodimeric proteins, technically more amenable for detailed quantitative biochemical and phylogenetic analyses. In this chapter, we summarize a collection of approaches, including bioinformatics, genetics, protein crystallography, in vitro biochemistry, and mutagenesis, together affording a comprehensive interrogation of the structure-function-evolutionary relationships in the plant type III PKS family.

  1. Biochemical aspects of Huntington's chorea.

    PubMed Central

    Caraceni, T; Calderini, G; Consolazione, A; Riva, E; Algeri, S; Girotti, F; Spreafico, R; Branciforti, A; Dall'olio, A; Morselli, P L

    1977-01-01

    Fifteen patients affected by Huntington's chorea were divided into two groups, 'slow' and 'fast', according to IQ scores on the Wechsler-Bellevue scale, and scores on some motor performance tests. A possible correlation was looked for between some biochemical data (cerebrospinal fluid (CSF), homovanillic acid (HVA), and 5-hydroxyindolacetic acid (5HIAA) levels, plasma dopamine-beta-hydroxylase (DBH), dopamine (DA) uptake by platelets), and clinical data (duration of illness, severity of symptoms, age of patients, IQ scores, 'slow' and 'fast' groups). The CSF, HVA, and 5HIAA levels were found to be significantly lowered in comparison with normal controls. DBH activity and DA uptake by platelets did not differ significantly from normal subjects. Treatment with haloperidol in all patients and with dipropylacetic acid in three patients did not appear to modify the CSF, HVA, and 5HIAA concentrations, the plasma DBH activity, or the DA uptake. There were no significant differences in the CSF, HVA, and 5HIAA contents between the two groups of patients, and there was no correlation between biochemical data and clinical features. PMID:143508

  2. Biochemical abnormalities in Pearson syndrome.

    PubMed

    Crippa, Beatrice Letizia; Leon, Eyby; Calhoun, Amy; Lowichik, Amy; Pasquali, Marzia; Longo, Nicola

    2015-03-01

    Pearson marrow-pancreas syndrome is a multisystem mitochondrial disorder characterized by bone marrow failure and pancreatic insufficiency. Children who survive the severe bone marrow dysfunction in childhood develop Kearns-Sayre syndrome later in life. Here we report on four new cases with this condition and define their biochemical abnormalities. Three out of four patients presented with failure to thrive, with most of them having normal development and head size. All patients had evidence of bone marrow involvement that spontaneously improved in three out of four patients. Unique findings in our patients were acute pancreatitis (one out of four), renal Fanconi syndrome (present in all patients, but symptomatic only in one), and an unusual organic aciduria with 3-hydroxyisobutyric aciduria in one patient. Biochemical analysis indicated low levels of plasma citrulline and arginine, despite low-normal ammonia levels. Regression analysis indicated a significant correlation between each intermediate of the urea cycle and the next, except between ornithine and citrulline. This suggested that the reaction catalyzed by ornithine transcarbamylase (that converts ornithine to citrulline) might not be very efficient in patients with Pearson syndrome. In view of low-normal ammonia levels, we hypothesize that ammonia and carbamylphosphate could be diverted from the urea cycle to the synthesis of nucleotides in patients with Pearson syndrome and possibly other mitochondrial disorders.

  3. Thermodynamic constraints for biochemical networks.

    PubMed

    Beard, Daniel A; Babson, Eric; Curtis, Edward; Qian, Hong

    2004-06-07

    The constraint-based approach to analysis of biochemical systems has emerged as a useful tool for rational metabolic engineering. Flux balance analysis (FBA) is based on the constraint of mass conservation; energy balance analysis (EBA) is based on non-equilibrium thermodynamics. The power of these approaches lies in the fact that the constraints are based on physical laws, and do not make use of unknown parameters. Here, we show that the network structure (i.e. the stoichiometric matrix) alone provides a system of constraints on the fluxes in a biochemical network which are feasible according to both mass balance and the laws of thermodynamics. A realistic example shows that these constraints can be sufficient for deriving unambiguous, biologically meaningful results. The thermodynamic constraints are obtained by comparing of the sign pattern of the flux vector to the sign patterns of the cycles of the internal cycle space via connection between stoichiometric network theory (SNT) and the mathematical theory of oriented matroids.

  4. Antithrombin III blood test

    MedlinePlus

    ... AT III) is a protein that helps control blood clotting. A blood test can determine the amount of ... may mean you have an increased risk of blood clotting. This can occur when there is not enough ...

  5. How special is the biochemical function of native proteins?

    PubMed

    Skolnick, Jeffrey; Gao, Mu; Zhou, Hongyi

    2016-01-01

    Native proteins perform an amazing variety of biochemical functions, including enzymatic catalysis, and can engage in protein-protein and protein-DNA interactions that are essential for life. A key question is how special are these functional properties of proteins. Are they extremely rare, or are they an intrinsic feature? Comparison to the properties of compact conformations of artificially generated compact protein structures selected for thermodynamic stability but not any type of function, the artificial (ART) protein library, demonstrates that a remarkable number of the properties of native-like proteins are recapitulated. These include the complete set of small molecule ligand-binding pockets and most protein-protein interfaces. ART structures are predicted to be capable of weakly binding metabolites and cover a significant fraction of metabolic pathways, with the most enriched pathways including ancient ones such as glycolysis. Native-like active sites are also found in ART proteins. A small fraction of ART proteins are predicted to have strong protein-protein and protein-DNA interactions. Overall, it appears that biochemical function is an intrinsic feature of proteins which nature has significantly optimized during evolution. These studies raise questions as to the relative roles of specificity and promiscuity in the biochemical function and control of cells that need investigation.

  6. Impact of volcanism on the evolution of Lake Van (eastern Anatolia) III: Periodic (Nemrut) vs. episodic (Süphan) explosive eruptions and climate forcing reflected in a tephra gap between ca. 14 ka and ca. 30 ka

    NASA Astrophysics Data System (ADS)

    Schmincke, Hans-Ulrich; Sumita, Mari

    2014-09-01

    Fifteen Lateglacial to Holocene rhyolitic, dominantly primary tephra layers piston-cored and drilled (ICDP Paleovan drilling project) in western Lake Van (eastern Anatolia, Turkey) were precisely correlated to either of the two adjacent and active large volcanoes Nemrut and Süphan based on shard textures, mineralogy and mineral and glass compositions. The young peralkaline (comenditic to pantelleritic) primary rhyolitic Nemrut tephras are characterized by anorthoclase, hedenbergitic to augitic clinopyroxene, fayalitic olivine, minor quartz, and rare accessory chevkinite and zircon. Phenocrysts in subalkaline primary rhyolitic Süphan tephras are chiefly oligoclase-labradorite, with minor K-rich sanidine in some, biotite, amphibole, hypersthene, rare augitic clinopyroxene, relatively common allanite and rare zircon. Two contrasting explosive eruptive modes are distinguished from each other: episodic (Süphan) and periodic (Nemrut). The Lateglacial Süphan tephra swarm covers a short time interval of ca. 338 years between ca. 13,078 vy BP and 12,740 vy BP, eruptions having occurred statistically every ca. 42 years with especially short intervals between V-11 (reworked) and V-14. Causes for the strongly episodic Süphan explosive behavior might include seismic triggering of a volcano-magma system unable to erupt explosively without the benefit of external triggering, as reflected in pervasive faulting preceding the Süphan tephra swarm. Seismic triggering may have caused the rise of more mafic ("trachyandesitic") parent magma, heating near-surface pockets of highly evolved magma - that might have formed silicic domes during this stage of volcano evolution - resulting in ascent and finally explosive fragmentation of magma essentially by external factors, probably significantly enhanced by magma-water/ice interaction. Explosive eruptions of the Nemrut volcano system, interpreted to be underlain by a large fractionating magma reservoir, follow a more periodic mode of (a

  7. Diagnosis of hyperandrogenism: biochemical criteria.

    PubMed

    Stanczyk, Frank Z

    2006-06-01

    Biochemical derangements in ovarian, adrenal, and peripheral androgen production and metabolism play an important role in underlying causes of hyperandrogenism. Specific diagnostic serum markers such as testosterone (total) and dehydroepiandrosterone sulfate (DHEAS), respectively, may be helpful in the diagnosis of ovarian and adrenal hyperandrogenism, respectively. Validated immunoassays or mass spectrometry assays should be used to quantify testosterone, DHEAS and other principal androgens. Free testosterone measurements, determined by equilibrium dialysis or the calculated method, are advocated for routine evaluation of more subtle forms of hyperandrogenism. The skin, with its pilosebaceous units (PSUs), is an important site of active androgen production. A key regulator in PSUs is 5alpha-reductase, which transforms testosterone or androstenedione to dihydrotestosterone (DHT). DHT in blood is not effective in indicating the presence of hyperandrogenism. However, distal metabolites of DHT have been shown to be good markers of clinical manifestations of hirsutism, acne and alopecia. Assays for these peripheral markers need improvement for routine clinical testing.

  8. Biochemical nature of Russell Bodies

    PubMed Central

    Francesca Mossuto, Maria; Ami, Diletta; Anelli, Tiziana; Fagioli, Claudio; Maria Doglia, Silvia; Sitia, Roberto

    2015-01-01

    Professional secretory cells produce and release abundant proteins. Particularly in case of mutations and/or insufficient chaperoning, these can aggregate and become toxic within or amongst cells. Immunoglobulins (Ig) are no exception. In the extracellular space, certain Ig-L chains form fibrils causing systemic amyloidosis. On the other hand, Ig variants lacking the first constant domain condense in dilated cisternae of the early secretory compartment, called Russell Bodies (RB), frequently observed in plasma cell dyscrasias, autoimmune diseases and chronic infections. RB biogenesis can be recapitulated in lymphoid and non-lymphoid cells by expressing mutant Ig-μ, providing powerful models to investigate the pathophysiology of endoplasmic reticulum storage disorders. Here we analyze the aggregation propensity and the biochemical features of the intra- and extra-cellular Ig deposits in human cells, revealing β-aggregated features for RB. PMID:26223695

  9. Biochemical nature of Russell Bodies.

    PubMed

    Mossuto, Maria Francesca; Ami, Diletta; Anelli, Tiziana; Fagioli, Claudio; Doglia, Silvia Maria; Sitia, Roberto

    2015-07-30

    Professional secretory cells produce and release abundant proteins. Particularly in case of mutations and/or insufficient chaperoning, these can aggregate and become toxic within or amongst cells. Immunoglobulins (Ig) are no exception. In the extracellular space, certain Ig-L chains form fibrils causing systemic amyloidosis. On the other hand, Ig variants lacking the first constant domain condense in dilated cisternae of the early secretory compartment, called Russell Bodies (RB), frequently observed in plasma cell dyscrasias, autoimmune diseases and chronic infections. RB biogenesis can be recapitulated in lymphoid and non-lymphoid cells by expressing mutant Ig-μ, providing powerful models to investigate the pathophysiology of endoplasmic reticulum storage disorders. Here we analyze the aggregation propensity and the biochemical features of the intra- and extra-cellular Ig deposits in human cells, revealing β-aggregated features for RB.

  10. Campylobacter jejuni Group III Phage CP81 Contains Many T4-Like Genes without Belonging to the T4-Type Phage Group: Implications for the Evolution of T4 Phages▿†

    PubMed Central

    Hammerl, Jens A.; Jäckel, Claudia; Reetz, Jochen; Beck, Sebastian; Alter, Thomas; Lurz, Rudi; Barretto, Caroline; Brüssow, Harald; Hertwig, Stefan

    2011-01-01

    CP81 is a virulent Campylobacter group III phage whose linear genome comprises 132,454 bp. At the nucleotide level, CP81 differs from other phages. However, a number of its structural and replication/recombination proteins revealed a relationship to the group II Campylobacter phages CP220/CPt10 and to T4-type phages. Unlike the T4-related phages, the CP81 genome does not contain conserved replication and virion modules. Instead, the respective genes are scattered throughout the phage genome. Moreover, most genes for metabolic enzymes of CP220/CPt10 are lacking in CP81. On the other hand, the CP81 genome contains nine similar genes for homing endonucleases which may be involved in the attrition of the conserved gene order for the virion core genes of T4-type phages. The phage apparently possesses an unusual modification of C or G bases. Efficient cleavage of its DNA was only achieved with restriction enzymes recognizing pure A/T sites. Uncommonly, phenol extraction leads to a significant loss of CP81 DNA from the aqueous layer, a property not yet described for other phages belonging to the T4 superfamily. PMID:21697478

  11. Computational optimization and biological evolution.

    PubMed

    Goryanin, Igor

    2010-10-01

    Modelling and optimization principles become a key concept in many biological areas, especially in biochemistry. Definitions of objective function, fitness and co-evolution, although they differ between biology and mathematics, are similar in a general sense. Although successful in fitting models to experimental data, and some biochemical predictions, optimization and evolutionary computations should be developed further to make more accurate real-life predictions, and deal not only with one organism in isolation, but also with communities of symbiotic and competing organisms. One of the future goals will be to explain and predict evolution not only for organisms in shake flasks or fermenters, but for real competitive multispecies environments.

  12. Serum Biochemical Phenotypes in the Domestic Dog.

    PubMed

    Chang, Yu-Mei; Hadox, Erin; Szladovits, Balazs; Garden, Oliver A

    2016-01-01

    The serum or plasma biochemical profile is essential in the diagnosis and monitoring of systemic disease in veterinary medicine, but current reference intervals typically take no account of breed-specific differences. Breed-specific hematological phenotypes have been documented in the domestic dog, but little has been published on serum biochemical phenotypes in this species. Serum biochemical profiles of dogs in which all measurements fell within the existing reference intervals were retrieved from a large veterinary database. Serum biochemical profiles from 3045 dogs were retrieved, of which 1495 had an accompanying normal glucose concentration. Sixty pure breeds plus a mixed breed control group were represented by at least 10 individuals. All analytes, except for sodium, chloride and glucose, showed variation with age. Total protein, globulin, potassium, chloride, creatinine, cholesterol, total bilirubin, ALT, CK, amylase, and lipase varied between sexes. Neutering status significantly impacted all analytes except albumin, sodium, calcium, urea, and glucose. Principal component analysis of serum biochemical data revealed 36 pure breeds with distinctive phenotypes. Furthermore, comparative analysis identified 23 breeds with significant differences from the mixed breed group in all biochemical analytes except urea and glucose. Eighteen breeds were identified by both principal component and comparative analysis. Tentative reference intervals were generated for breeds with a distinctive phenotype identified by comparative analysis and represented by at least 120 individuals. This is the first large-scale analysis of breed-specific serum biochemical phenotypes in the domestic dog and highlights potential genetic components of biochemical traits in this species.

  13. Biochemical transformation of solid carbonaceous material

    DOEpatents

    Lin, Mow S.; Premuzic, Eugene T.

    2001-09-25

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed.

  14. Serum Biochemical Phenotypes in the Domestic Dog

    PubMed Central

    Chang, Yu-Mei; Hadox, Erin; Szladovits, Balazs; Garden, Oliver A.

    2016-01-01

    The serum or plasma biochemical profile is essential in the diagnosis and monitoring of systemic disease in veterinary medicine, but current reference intervals typically take no account of breed-specific differences. Breed-specific hematological phenotypes have been documented in the domestic dog, but little has been published on serum biochemical phenotypes in this species. Serum biochemical profiles of dogs in which all measurements fell within the existing reference intervals were retrieved from a large veterinary database. Serum biochemical profiles from 3045 dogs were retrieved, of which 1495 had an accompanying normal glucose concentration. Sixty pure breeds plus a mixed breed control group were represented by at least 10 individuals. All analytes, except for sodium, chloride and glucose, showed variation with age. Total protein, globulin, potassium, chloride, creatinine, cholesterol, total bilirubin, ALT, CK, amylase, and lipase varied between sexes. Neutering status significantly impacted all analytes except albumin, sodium, calcium, urea, and glucose. Principal component analysis of serum biochemical data revealed 36 pure breeds with distinctive phenotypes. Furthermore, comparative analysis identified 23 breeds with significant differences from the mixed breed group in all biochemical analytes except urea and glucose. Eighteen breeds were identified by both principal component and comparative analysis. Tentative reference intervals were generated for breeds with a distinctive phenotype identified by comparative analysis and represented by at least 120 individuals. This is the first large-scale analysis of breed-specific serum biochemical phenotypes in the domestic dog and highlights potential genetic components of biochemical traits in this species. PMID:26919479

  15. Influence of low-frequency vibration on changes of biochemical parameters of living rats

    NASA Astrophysics Data System (ADS)

    Kasprzak, Cezary; Damijan, Zbigniew; Panuszka, Ryszard

    2004-05-01

    The aim of the research was to investigate how some selected biochemical parameters of living rats depend on exposure of low-frequency vibrations. Experiments were run on 30 Wistar rats randomly segregated into three groups: (I) 20 days old (before puberty), (II) 70th day after; (III) control group. The exposure was repeated seven times, for 3 h, at the same time of day. Vibrations applied during the first tests of the experiment had acceleration 1.22 m/s2 and frequency 20 Hz. At the 135th day the rats' bones were a subject of morphometric/biochemical examination. The results of biochemical tests proved decrease in LDL and HDL cholesterol levels for exposed rats as well as the Ca contents in blood plasma. There was evident increasing of Ca in blood plasma in exposed rats for frequency of exposition.

  16. Type III burst pair

    NASA Astrophysics Data System (ADS)

    Ning, Zongjun; Fu, Qijun; Lu, Quankang

    2000-05-01

    We present a special solar radio burst detected on 5 January 1994 using the multi-channel (50) spectrometer (1.0-2.0 GHz) of the Beijing Astronomical Observatory (BAO). Sadly, the whole event could not be recorded since it had a broader bandwidth than the limit range of the instrument. The important part was obtained, however. The event is composed of a normal drift type III burst on the lower frequency side and a reverse drift type III burst appearing almost simultaneously on the high side. We call the burst type III a burst pair. It is a typical characteristic of two type III bursts that they are morphologically symmetric about some frequency from 1.64 GHz to 1.78 GHz on the dynamic spectra records, which indicates that there are two different electron beams from the same acceleration region travelling simultaneously in opposite directions (upward and downward). A magnetic reconnection mode is a nice interpretation of type III burst pair since the plasma beta β~=0.01 is much less than 1 and the beams have velocity of about 1.07×10^8 cm s^-1 after leaving the reconnection region if we assume that the ambient magnetic field strength is about 100 G.

  17. Type III burst pair.

    NASA Astrophysics Data System (ADS)

    Zongjun, Ning; Fu, Qijun; Quankang, Lu

    2000-05-01

    Presents a special solar radio burst detected on 5 January 1994 using the multi-channel (50) spectrometer (1.0 - 2.0 GHz) of the Beijing Astronomical Observatory. Sadly, the whole event could not be recorded since it had a broader bandwidth than the limit range of the instrument. The important part was obtained, however. The event is composed of a normal drift type III burst on the lower frequency side and a reverse drift type III burst appearing almost simultaneously on the high side. The authors call the burst type III a burst pair. It is a typical characteristic of two type III bursts that they are morphologically symmetric about some frequency from 1.64 GHz to 1.78 GHz on the dynamic spectra records, which indicates that there are two different electron beams from the same acceleration region travelling simultaneously in opposite directions (upward and downward). A magnetic reconnection mode is an interpretation of type III burst pair.

  18. Biochemical and physiological processes associated with the differential ozone response in ozone-tolerant and sensitive soybean genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochemical and physiological traits of two soybean [Glycine max (L.) Merr.] genotypes that differ in sensitivity to ozone (O3) were investigated to determine the possible basis for the differential response. Fiskeby III (O3-tolerant) and Mandarin (Ottawa) (O3-sensitive) were grown in a greenhouse ...

  19. Evolution of chromospheres and coronae in solar mass stars - A far-ultraviolet and soft X-ray comparison of Arcturus /K2 III/ and Alpha Centauri A /G2 V/

    NASA Technical Reports Server (NTRS)

    Ayres, T. R.; Simon, T.; Linsky, J. L.

    1982-01-01

    IUE far-UV and Einstein Observatory soft X-ray observations for the red giant Arcturus and the nearby yellow dwarf Alpha-Centauri A, which are archetypes of solar mass stars in different stages of evolution, are compared. Evidence is found for neither coronal soft X-ray emission from the red giant, at surface flux levels of only 0.0006 that detected previously for the yellow dwarf, nor C II and IV resonance line emission at surface flux levels of only 0.02 those of the yellow dwarf. The resonance line upper limits and previous detections of the C II intersystem UV multiplet 0.01 near 2325 A provide evidence for an Arcturus outer atmosphere that is geometrically extended, tenuous and cool. The red giant has, in addition, a prominent cool stellar wind. An extensive tabulation of line identifications, widths and fluxes for the IUE far-UV echelle spectra of the two stars is given, and two competing explanations for the Wilson-Bappu effect are discussed.

  20. The chemical master equation approach to nonequilibrium steady-state of open biochemical systems: linear single-molecule enzyme kinetics and nonlinear biochemical reaction networks.

    PubMed

    Qian, Hong; Bishop, Lisa M

    2010-09-20

    We develop the stochastic, chemical master equation as a unifying approach to the dynamics of biochemical reaction systems in a mesoscopic volume under a living environment. A living environment provides a continuous chemical energy input that sustains the reaction system in a nonequilibrium steady state with concentration fluctuations. We discuss the linear, unimolecular single-molecule enzyme kinetics, phosphorylation-dephosphorylation cycle (PdPC) with bistability, and network exhibiting oscillations. Emphasis is paid to the comparison between the stochastic dynamics and the prediction based on the traditional approach based on the Law of Mass Action. We introduce the difference between nonlinear bistability and stochastic bistability, the latter has no deterministic counterpart. For systems with nonlinear bistability, there are three different time scales: (a) individual biochemical reactions, (b) nonlinear network dynamics approaching to attractors, and (c) cellular evolution. For mesoscopic systems with size of a living cell, dynamics in (a) and (c) are stochastic while that with (b) is dominantly deterministic. Both (b) and (c) are emergent properties of a dynamic biochemical network; We suggest that the (c) is most relevant to major cellular biochemical processes such as epi-genetic regulation, apoptosis, and cancer immunoediting. The cellular evolution proceeds with transitions among the attractors of (b) in a "punctuated equilibrium" manner.

  1. The Chemical Master Equation Approach to Nonequilibrium Steady-State of Open Biochemical Systems: Linear Single-Molecule Enzyme Kinetics and Nonlinear Biochemical Reaction Networks

    PubMed Central

    Qian, Hong; Bishop, Lisa M.

    2010-01-01

    We develop the stochastic, chemical master equation as a unifying approach to the dynamics of biochemical reaction systems in a mesoscopic volume under a living environment. A living environment provides a continuous chemical energy input that sustains the reaction system in a nonequilibrium steady state with concentration fluctuations. We discuss the linear, unimolecular single-molecule enzyme kinetics, phosphorylation-dephosphorylation cycle (PdPC) with bistability, and network exhibiting oscillations. Emphasis is paid to the comparison between the stochastic dynamics and the prediction based on the traditional approach based on the Law of Mass Action. We introduce the difference between nonlinear bistability and stochastic bistability, the latter has no deterministic counterpart. For systems with nonlinear bistability, there are three different time scales: (a) individual biochemical reactions, (b) nonlinear network dynamics approaching to attractors, and (c) cellular evolution. For mesoscopic systems with size of a living cell, dynamics in (a) and (c) are stochastic while that with (b) is dominantly deterministic. Both (b) and (c) are emergent properties of a dynamic biochemical network; We suggest that the (c) is most relevant to major cellular biochemical processes such as epi-genetic regulation, apoptosis, and cancer immunoediting. The cellular evolution proceeds with transitions among the attractors of (b) in a “punctuated equilibrium” manner. PMID:20957107

  2. Biochemical genetic markers in sugarcane.

    PubMed

    Glaszmann, J C; Fautret, A; Noyer, J L; Feldmann, P; Lanaud, C

    1989-10-01

    Isozyme variation was used to identify biochemical markers of potential utility in sugarcane genetics and breeding. Electrophoretic polymorphism was surveyed for nine enzymes among 39 wild and noble sugarcane clones, belonging to the species most closely related to modern varieties. Up to 114 distinct bands showing presence versus absence type of variation were revealed and used for qualitative characterization of the materials. Multivariate analysis of the data isolated the Erianthus clone sampled and separated the Saccharum spontaneum clones from the S. robustum and S. officinarum clones; the latter two were not differentiated from one another. The analysis of self-progenies of a 2n=112 S. spontaneum and of a commercial variety showed examples of mono- and polyfactorial segregations. Within the progeny of the variety, co-segregation of two isozymes frequent in S. spontaneum led to them being assigned to a single chromosome initially contributed by a S. spontaneum donor. This illustrates how combined survey of ancestral species and segregation analysis in modern breeding materials should permit using the lack of interspecific cross-over to establish linkage groups in a sugarcane genome.

  3. Fusion Power Demonstration III

    SciTech Connect

    Lee, J.D.

    1985-07-01

    This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report.

  4. Chemical Properties And Toxicity of Chromium(III) Nutritional Supplements

    SciTech Connect

    Levina, A.; Lay, P.A.

    2009-05-19

    The status of Cr(III) as an essential micronutrient for humans is currently under question. No functional Cr(III)-containing biomolecules have been definitively described as yet, and accumulated experience in the use of Cr(III) nutritional supplements (such as [Cr(pic){sub 3}], where pic = 2-pyridinecarboxylato) has shown no measurable benefits for nondiabetic people. Although the use of large doses of Cr(III) supplements may lead to improvements in glucose metabolism for type 2 diabetics, there is a growing concern over the possible genotoxicity of these compounds, particularly of [Cr(pic){sub 3}]. The current perspective discusses chemical transformations of Cr(III) nutritional supplements in biological media, with implications for both beneficial and toxic actions of Cr(III) complexes, which are likely to arise from the same biochemical mechanisms, dependent on concentrations of the reactive species. These species include: (1) partial hydrolysis products of Cr(III) nutritional supplements, which are capable of binding to biological macromolecules and altering their functions; and (2) highly reactive Cr(VI/V/IV) species and organic radicals, formed in reactions of Cr(III) with biological oxidants. Low concentrations of these species are likely to cause alterations in cell signaling (including enhancement of insulin signaling) through interactions with the active centers of regulatory enzymes in the cell membrane or in the cytoplasm, while higher concentrations are likely to produce genotoxic DNA lesions in the cell nucleus. These data suggest that the potential for genotoxic side-effects of Cr(III) complexes may outweigh their possible benefits as insulin enhancers, and that recommendations for their use as either nutritional supplements or antidiabetic drugs need to be reconsidered in light of these recent findings.

  5. Disconnecting XRCC1 and DNA ligase III.

    PubMed

    Katyal, Sachin; McKinnon, Peter J

    2011-07-15

    DNA strand break repair is essential for the prevention of multiple human diseases, particularly those which feature neuropathology. To further understand the pathogenesis of these syndromes, we recently developed animal models in which the DNA single-strand break repair (SSBR) components, XRCC1 and DNA Ligase III (LIG3), were inactivated in the developing nervous system. Although biochemical evidence suggests that inactivation of XRCC1 and LIG3 should share common biological defects, we found profound phenotypic differences between these two models, implying distinct biological roles for XRCC1 and LIG3 during DNA repair. Rather than a key role in nuclear DNA repair, we found LIG3 function was central to mitochondrial DNA maintenance. Instead, our data indicate that DNA Ligase 1 is the main DNA ligase for XRCC1-mediated DNA repair. These studies refine our understanding of DNA SSBR and the etiology of neurological disease.

  6. Disconnecting XRCC1 and DNA ligase III

    PubMed Central

    Katyal, Sachin

    2011-01-01

    DNA strand break repair is essential for the prevention of multiple human diseases, particularly those which feature neuropathology. To further understand the pathogenesis of these syndromes, we recently developed animal models in which the DNA single-strand break repair (SSBR) components, XRCC1 and DNA Ligase III (LIG3), were inactivated in the developing nervous system. Although biochemical evidence suggests that inactivation of XRCC1 and LIG3 should share common biological defects, we found profound phenotypic differences between these two models, implying distinct biological roles for XRCC1 and LIG3 during DNA repair. Rather than a key role in nuclear DNA repair, we found LIG3 function was central to mitochondrial DNA maintenance. Instead, our data indicate that DNA Ligase 1 is the main DNA ligase for XRCC1-mediated DNA repair. These studies refine our understanding of DNA SSBR and the etiology of neurological disease. PMID:21636980

  7. Summary of Session III

    SciTech Connect

    Furman, M.A.

    2002-06-19

    This is a summary of the talks presented in Session III ''Simulations of Electron-Cloud Build Up'' of the Mini-Workshop on Electron-Cloud Simulations for Proton and Positron Beams ECLOUD-02, held at CERN, 15-18 April 2002.

  8. The Apple III.

    ERIC Educational Resources Information Center

    Ditlea, Steve

    1982-01-01

    Describes and evaluates the features, performance, peripheral devices, available software, and capabilities of the Apple III microcomputer. The computer's operating system, its hardware, and the commercially produced software it accepts are discussed. Specific applications programs for financial planning, accounting, and word processing are…

  9. BES-III distributed computing status

    NASA Astrophysics Data System (ADS)

    Belov, S. D.; Deng, Z. Y.; Korenkov, V. V.; Li, W. D.; Lin, T.; Ma, Z. T.; Nicholson, C.; Pelevanyuk, I. S.; Suo, B.; Trofimov, V. V.; Tsaregorodtsev, A. U.; Uzhinskiy, A. V.; Yan, T.; Yan, X. F.; Zhang, X. M.; Zhemchugov, A. S.

    2016-09-01

    The BES-III experiment at the Institute of High Energy Physics (Beijing, China) is aimed at the precision measurements in e+e- annihilation in the energy range from 2.0 till 4.6 GeV. The world's largest samples of J/psi and psi' events and unique samples of XYZ data have been already collected. The expected increase of the data volume in the coming years required a significant evolution of the computing model, namely shift from a centralized data processing to a distributed one. This report summarizes a current design of the BES-III distributed computing system, some of key decisions and experience gained during 2 years of operations.

  10. Biochemical kinetics in changing volumes.

    PubMed

    Pawłowski, Piotr H; Zielenkiewicz, Piotr

    2004-01-01

    The need of taking into account the change of compartment volume when developing chemical kinetics analysis inside the living cell is discussed. Literature models of a single enzymatic Michaelis-Menten process, glycolytic oscillations, and mitotic cyclin oscillations were tested with appropriate theoretical extension in the direction of volume modification allowance. Linear and exponential type of volume increase regimes were compared. Due to the above, in a growing cell damping of the amplitude, phase shift, and time pattern deformation of the metabolic rhythms considered were detected, depending on the volume change character. The performed computer simulations allow us to conclude that evolution of the cell volume can be an essential factor of the chemical kinetics in a growing cell. The phenomenon of additional metabolite oscillations caused by the periodic cell growth and division was theoretically predicted and mathematically described. Also, the hypothesis of the periodized state in the growing cell as the generalization of the steady-state was formulated.

  11. Simulation of Biochemical Pathway Adaptability Using Evolutionary Algorithms

    SciTech Connect

    Bosl, W J

    2005-01-26

    The systems approach to genomics seeks quantitative and predictive descriptions of cells and organisms. However, both the theoretical and experimental methods necessary for such studies still need to be developed. We are far from understanding even the simplest collective behavior of biomolecules, cells or organisms. A key aspect to all biological problems, including environmental microbiology, evolution of infectious diseases, and the adaptation of cancer cells is the evolvability of genomes. This is particularly important for Genomes to Life missions, which tend to focus on the prospect of engineering microorganisms to achieve desired goals in environmental remediation and climate change mitigation, and energy production. All of these will require quantitative tools for understanding the evolvability of organisms. Laboratory biodefense goals will need quantitative tools for predicting complicated host-pathogen interactions and finding counter-measures. In this project, we seek to develop methods to simulate how external and internal signals cause the genetic apparatus to adapt and organize to produce complex biochemical systems to achieve survival. This project is specifically directed toward building a computational methodology for simulating the adaptability of genomes. This project investigated the feasibility of using a novel quantitative approach to studying the adaptability of genomes and biochemical pathways. This effort was intended to be the preliminary part of a larger, long-term effort between key leaders in computational and systems biology at Harvard University and LLNL, with Dr. Bosl as the lead PI. Scientific goals for the long-term project include the development and testing of new hypotheses to explain the observed adaptability of yeast biochemical pathways when the myosin-II gene is deleted and the development of a novel data-driven evolutionary computation as a way to connect exploratory computational simulation with hypothesis

  12. Biochemical Oscillations and Cellular Rhythms

    NASA Astrophysics Data System (ADS)

    Goldbeter, Albert; Berridge, Foreword by M. J.

    1997-04-01

    1. Introduction; Part I. Glycolytic Oscillations: 2. Oscillatory enzymes: simple periodic behaviour in an allosteric model for glycolytic oscillations; Part II. From Simple to Complex Oscillatory Behaviour; 3. Birhythmicity: coexistence between two stable rhythms; 4. From simple periodic behaviour to complex oscillations, including bursting and chaos; Part III. Oscillations Of Cyclic Amo In Dictyostelium Cells: 5. Models for the periodic synthesis and relay of camp signals in Dictyostelium discoideum amoebae; 6. Complex oscillations and chaos in the camp signalling system of Dictyostelium; 7. The onset of camp oscillations in Dictyostelium as a model for the ontogenesis of biological rhythms; Part IV. Pulsatile Signalling In Intercellular Communication: 8. Function of the rhythm of intercellular communication in Dictyostelium. Link with pulsatile hormone secretion; Part V. Calcium Oscillations: 9. Oscillations and waves of intracellular calcium; Part VI. The Mitotic Oscillator: 10. Modelling the mitotic oscillator driving the cell division cycle; Part VII. Circadian Rhythms: 11. Towards a model for circadian oscillations in the Drosophila period protein (PER); 12. Conclusions and perspectives; References.

  13. Pacific Barrier Radar III (PACBAR III)

    NASA Astrophysics Data System (ADS)

    Miller, C. D.; Sigler, J. D.

    1983-11-01

    The Pacific Barrier (PACBAR III) C-band radar is being installed at the Western Space and Missile Center to furnish Revolution 0 detection of foreign launches. Previously installed on a tracking ship, the upgraded system will also identify and target space objects, maintain a catalog, and cover maneuvers and decay of space objects. Nominal operation will comprise a search of a predesignated 15 deg azimuth with the capability of detecting a 6 sq m target in a 400 km orbit, track spacecraft in orbits up to 800 km altitude, have a range resolution of about 80 yd, provide realtime payload and rocket body discrimination, and transmit two-way digital message traffic between the Center and NORAD in Cheyenne Mt. Interlaced vertical and horizontal pulses will augment the search and acquisition capabilities, and the antenna will have a 140 deg plunge range. The transmitter will function at 5.4-5.65 GHz, 320 p/sec, with a peak power of 0.8 MW, and the system will have a nonambiguous range of 32,768 nmi.

  14. A Program on Biochemical and Biomedical Engineering.

    ERIC Educational Resources Information Center

    San, Ka-Yiu; McIntire, Larry V.

    1989-01-01

    Presents an introduction to the Biochemical and Biomedical Engineering program at Rice University. Describes the development of the academic and enhancement programs, including organizational structure and research project titles. (YP)

  15. Photon track evolution.

    PubMed

    Oliveira, A D

    2005-01-01

    Given the time scale of biological, biochemical, biophysical and physical effects in a radiation exposure of living tissue, the first physical stage can be considered to be independent of time. All the physical interactions caused by the incident photons happen at the same starting time. From this point of view it would seem that the evolution of photon tracks is not a relevant topic for analysis; however, if the photon track is considered as a sequence of several interactions, there are several steps until the total degradation of the energy of the primary photon. We can characterise the photon track structure by the probability p(E,j), that is, the probability that a photon with energy E suffers j secondary interactions. The aim of this work is to analyse the photon track structure by considering j as a step of the photon track evolution towards the total degradation of the photon energy. Low energy photons (<150 keV) are considered, with water phantoms and half-extended geometry. The photon track evolution concept is presented and compared with the energy deposition along the track and also with the spatial distribution of the several steps in the photon track.

  16. Effect of Population III Multiplicity on Dark Star Formation

    NASA Technical Reports Server (NTRS)

    Stacy, Athena; Pawlik, Andreas H.; Bromm, Volker; Loeb, Abraham

    2012-01-01

    We numerically study the mutual interaction between dark matter (DM) and Population III (Pop III) stellar systems in order to explore the possibility of Pop III dark stars within this physical scenario. We perform a cosmological simulation, initialized at z approx. 100, which follows the evolution of gas and DM. We analyze the formation of the first mini halo at z approx. 20 and the subsequent collapse of the gas to densities of 10(exp 12)/cu cm. We then use this simulation to initialize a set of smaller-scale 'cut-out' simulations in which we further refine the DM to have spatial resolution similar to that of the gas. We test multiple DM density profiles, and we employ the sink particle method to represent the accreting star-forming region. We find that, for a range of DM configurations, the motion of the Pop III star-disk system serves to separate the positions of the protostars with respect to the DM density peak, such that there is insufficient DM to influence the formation and evolution of the protostars for more than approx. 5000 years. In addition, the star-disk system causes gravitational scattering of the central DM to lower densities, further decreasing the influence of DM over time. Any DM-powered phase of Pop III stars will thus be very short-lived for the typical multiple system, and DM will not serve to significantly prolong the life of Pop III stars.

  17. Biochemical-Pathway Diversity in Archaebacteria

    DTIC Science & Technology

    1990-08-30

    characteristic of much or all of the Gram-positive lineage of eubacteria . We have extended the enzymological base of information to include organisms...to compare the biochemical diversitv within the archaebacteria to the biochemical diversity already known or now emerging within the eubacteria . RAI...INALL: In eubacteria aromatic-pathway character states are exceedingly diverse. A given feature will cluster at a hierarchical level ot phylogeny that

  18. [Biochemical diagnostics of fatal opium intoxication].

    PubMed

    Papyshev, I P; Astashkina, O G; Tuchik, E S; Nikolaev, B S; Cherniaev, A L

    2013-01-01

    Biochemical diagnostics of fatal opium intoxication remains a topical problem in forensic medical science and practice. We investigated materials obtained in the course of forensic medical expertise of the cases of fatal opium intoxication. The study revealed significant differences between myoglobin levels in blood, urine, myocardium, and skeletal muscles. The proposed approach to biochemical diagnostics of fatal opium intoxication enhances the accuracy and the level of evidence of expert conclusions.

  19. Lower glycolysis carries a higher flux than any biochemically possible alternative

    PubMed Central

    Court, Steven J.; Waclaw, Bartlomiej; Allen, Rosalind J.

    2015-01-01

    The universality of many pathways of core metabolism suggests a strong role for evolutionary selection, but it remains unclear whether existing pathways have been selected from a large or small set of biochemical possibilities. To address this question, we construct in silico all possible biochemically feasible alternatives to the trunk pathway of glycolysis and gluconeogenesis, one of the most highly conserved pathways in metabolism. We show that, even though a large number of alternative pathways exist, the alternatives carry lower flux than the real pathway under typical physiological conditions. We also find that if physiological conditions were different, different pathways could outperform those found in nature. Together, our results demonstrate how thermodynamic and biophysical constraints restrict the biochemical alternatives that are open to evolution, and suggest that the existing trunk pathway of glycolysis and gluconeogenesis may represent a maximal flux solution. PMID:26416228

  20. A general method for modeling biochemical and biomedical response

    NASA Astrophysics Data System (ADS)

    Ortiz, Roberto; Lerd Ng, Jia; Hughes, Tyler; Abou Ghantous, Michel; Bouhali, Othmane; Arredouani, Abdelilah; Allen, Roland

    2012-10-01

    The impressive achievements of biomedical science have come mostly from experimental research with human subjects, animal models, and sophisticated laboratory techniques. Additionally, theoretical chemistry has been a major aid in designing new drugs. Here we introduce a method which is similar to others already well known in theoretical systems biology, but which specifically addresses biochemical changes as the human body responds to medical interventions. It is common in systems biology to use first-order differential equations to model the time evolution of various chemical concentrations, and we as physicists can make a significant impact through designing realistic models and then solving the resulting equations. Biomedical research is rapidly advancing, and the technique presented in this talk can be applied in arbitrarily large models containing tens, hundreds, or even thousands of interacting species, to determine what beneficial effects and side effects may result from pharmaceuticals or other medical interventions.

  1. The Mark III VLBI System

    NASA Technical Reports Server (NTRS)

    Rogers, A. E. E.; Whitney, A. R.; Levine, J. I.; Nesman, E. F.; Webber, J. C.; Hinteregger, H. F.

    1988-01-01

    Geodetic measurements have errors in centimeter range. Collection of three reports describes both equipment and results of some measurements taken with Mark III very-long-baseline interferometry (VLBI) system. Has demonstrated high accuracy over short baselines, where phase-delay measurements used. Advanced hardware, called Mark III A, developed to improve system performance and efficiency. Original Mark III hardware and III A subsystem upgrades developed as part of NASA Crustal Dynamics Project at Haystack Observatory.

  2. ESCRT-III on endosomes: new functions, new activation pathway.

    PubMed

    Woodman, Philip

    2016-01-15

    The multivesicular body (MVB) pathway sorts ubiquitinated membrane cargo to intraluminal vesicles (ILVs) within the endosome, en route to the lysosomal lumen. The pathway involves the sequential action of conserved protein complexes [endosomal sorting complexes required for transport (ESCRTs)], culminating in the activation by ESCRT-II of ESCRT-III, a membrane-sculpting complex. Although this linear pathway of ESCRT activation is widely accepted, a study by Luzio and colleagues in a recent issue of the Biochemical Journal suggests that there is greater complexity in ESCRT-III activation, at least for some MVB cargoes. They show that ubiquitin-dependent sorting of major histocompatibility complex (MHC) class I to the MVB requires the central ESCRT-III complex but does not involve either ESCRT-II or functional links between ESCRT-II and ESCRT-III. Instead, they propose that MHC class I utilizes histidine-domain protein tyrosine phosphatase (HD-PTP), a non-canonical ESCRT interactor, to promote ESCRT-III activation.

  3. Behind the scene with the fathead team: Part III. Molecular, biochemical, and in vitro analyses

    EPA Science Inventory

    As part of a research team focused on aquatic toxicity testing using fathead minnows as a model species, this presentation is the third in the three-part series, giving an overview of the types of field and laboratory studies as well as sample processing our team conducts at the ...

  4. FTS evolution

    NASA Technical Reports Server (NTRS)

    Provost, David E.

    1990-01-01

    Viewgraphs on flight telerobotic servicer evolution are presented. Topics covered include: paths for FTS evolution; frequently performed actions; primary task states; EPS radiator panel installation; generic task definitions; path planning; non-contact alignment; contact planning and control; and human operator interface.

  5. Teaching Evolution

    ERIC Educational Resources Information Center

    Bryner, Jeanna

    2005-01-01

    Eighty years after the famous 1925 Scopes "monkey trial," which tested a teacher's right to discuss the theory of evolution in the classroom, evolution--and its most recent counterview, called "intelligent design"--are in the headlines again, and just about everyone seems to have an opinion. This past July, President Bush weighed in, telling…

  6. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  7. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  8. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  9. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  10. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Biochemical pesticides definition and...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2000 Biochemical pesticides definition and applicability. This subpart applies to all biochemical pesticides as defined in paragraphs...

  11. Medical treatment for biochemical relapse after radiotherapy.

    PubMed

    Quero, L; Hennequin, C

    2014-10-01

    This article's purpose was to review the medical data justifying the use of a medical treatment for biochemical relapse after external beam radiotherapy. The MEDLINE database was searched to identify relevant information with the following medical subject headings: "prostate cancer", "radiotherapy" and "biochemical relapse". Prognostic factors affecting the overall survival of patients with a biochemical relapse after external beam radiotherapy have been identified: short prostate specific antigen (PSA)-doubling time (< 12 months), high PSA value (> 10 ng/mL) and short interval between treatment and biochemical relapse (< 18 months). If a second local treatment is not feasible, timing to initiate a salvage medical treatment is not defined. Particularly, randomized trials did not demonstrate a significant benefit of an early initiation of androgen deprivation treatment. Some retrospective studies suggest that an early androgen deprivation is justified if poor prognostic factors are found. However, if an androgen deprivation treatment is prescribed, intermittent schedule is non-inferior to a continuous administration and seems to offer a better quality of life. Many non-hormonal treatments have also been evaluated in this setting: only 5-alpha-reductase inhibitors could be proposed in some specific situations. In conclusion, the judicious use of a medical treatment for biochemical relapse is still debated. Given the natural history of this clinical situation, a simple surveillance is justified in many cases.

  12. Nonlinear biochemical signal processing via noise propagation

    NASA Astrophysics Data System (ADS)

    Kim, Kyung Hyuk; Qian, Hong; Sauro, Herbert M.

    2013-10-01

    Single-cell studies often show significant phenotypic variability due to the stochastic nature of intra-cellular biochemical reactions. When the numbers of molecules, e.g., transcription factors and regulatory enzymes, are in low abundance, fluctuations in biochemical activities become significant and such "noise" can propagate through regulatory cascades in terms of biochemical reaction networks. Here we develop an intuitive, yet fully quantitative method for analyzing how noise affects cellular phenotypes based on identifying a system's nonlinearities and noise propagations. We observe that such noise can simultaneously enhance sensitivities in one behavioral region while reducing sensitivities in another. Employing this novel phenomenon we designed three biochemical signal processing modules: (a) A gene regulatory network that acts as a concentration detector with both enhanced amplitude and sensitivity. (b) A non-cooperative positive feedback system, with a graded dose-response in the deterministic case, that serves as a bistable switch due to noise-induced ultra-sensitivity. (c) A noise-induced linear amplifier for gene regulation that requires no feedback. The methods developed in the present work allow one to understand and engineer nonlinear biochemical signal processors based on fluctuation-induced phenotypes.

  13. Type III Hyperlipoproteinaemia

    PubMed Central

    Borrie, Peter

    1969-01-01

    Eighteen patients with type III hyperlipoproteinaemia, diagnosed on the basis of skin lesions, serum lipids, and lipoprotein electrophoresis, have been fully investigated over a period of 15 years. The incidence of coronary artery disease was only slightly increased, and was not increased at all among first-degree relatives. Peripheral occlusive arterial disease was probably more common. An increased incidence of carbohydrate intolerance was found in neither the patients nor their relatives. The effects of treatment on the skin were uniformly good. ImagesFig. 1Fig. 2 PMID:5783124

  14. Biochemical alterations induced by oral subchronic exposure to fipronil, fluoride and their combination in buffalo calves.

    PubMed

    Gill, Kamalpreet Kaur; Dumka, Vinod Kumar

    2013-11-01

    The effects of various pesticides and minerals on biochemical parameters have been explored in different species, but hardly any data exist regarding the combined toxicological effect of pesticides and minerals on these parameters in animals. The present study investigated the effects of fipronil and fluoride co-exposure on biochemical parameters in buffalo calves. Twenty-four healthy male buffalo calves divided into four groups were treated for 98 consecutive days. Group I, receiving no treatment served as the control. Animals of groups II and III were orally administered with fipronil @ 0.5mg/kg/day and sodium fluoride (NaF) @ 6.67 mg/kg/day, respectively, for 98 days. An additional group IV was co-administered fipronil and NaF at the same dosages as groups II and III. Administration of fipronil alone produced mild toxic signs, significant elevation in plasma proteins, blood glucose, blood urea nitrogen (BUN) and significant decline in the plasma cholesterol levels. NaF exposure produced toxic signs specifically of muscle weakness and brown and black discoloration of teeth. Significant elevation was seen in whole blood cholinesterase, BUN and creatinine levels. However, it produced significant decline in blood glucose, cholesterol and plasma protein levels. Combined exposure to fipronil and sodium fluoride produced toxic signs with greater intensity while biochemical alterations produced were similar to those that were produced by their individual exposures.

  15. Chemical evolution and the origin of life

    NASA Technical Reports Server (NTRS)

    Oro, J.

    1983-01-01

    A review is presented of recent advances made in the understanding of the formation of carbon compounds in the universe and the occurrence of processes of chemical evolution. Topics discussed include the principle of evolutionary continuity, evolution as a fundamental principle of the physical universe, the nuclear synthesis of biogenic elements, organic cosmochemistry and interstellar molecules, the solar nebula and the solar system in chemical evolution, the giant planets and Titan in chemical evolution, and comets and their interaction with the earth. Also examined are carbonaceous chondrites, environment of the primitive earth, energy sources available on the primitive earth, the synthesis of biochemical monomers and oligomers, the abiotic transcription of nucleotides, unified prebiotic and enzymatic mechanisms, phospholipids and membranes, and protobiological evolution.

  16. Sloan Digital Sky Survey III (SDSS-III), Data Release 8

    DOE Data Explorer

    Building on the legacy of the Sloan Digital Sky Survey (SDSS) and SDSS-II, the SDSS-III Collaboration is working to map the Milky Way, search for extrasolar planets, and solve the mystery of dark energy. SDSS-III's first release, Data Release 8 (DR8), became available in the first half of 2012. DR8 contains all the images ever taken by the SDSS telescope. Together, these images make up the largest color image of the sky ever made. A version of the DR8 image is shown to the right. DR8 also includes measurements for nearly 500 million stars, galaxies, and quasars, and spectra for nearly two million. All of DR8's images, spectra, and measurements are available to anyone online. You can browse through sky images, look up data for individual objects, or search for objects anywhere using any criteria. SDSS-III will collect data from 2008 to 2014, using the 2.5-meter telescope at Apache Point Observatory. SDSS-III consists of four surveys, each focused on a different scientific theme. These four surveys are: 1) Baryon Oscillation Spectroscopic Survey (BOSS); 2) SEGUE-2 (Sloan Extension for Galactic Understanding and Exploration); 3) The APO Galactic Evolution Experiment (APOGEE); and 4) The Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). [Copied with edits from http://www.sdss3.org/index.php

  17. Biochemical Removal of HAP Precursors From Coal

    SciTech Connect

    Olson, G.; Tucker, L.; Richards, J.

    1997-07-01

    This project addresses DOE`s interest in advanced concepts for controlling emissions of air toxics from coal-fired utility boilers. We are determining the feasibility of developing a biochemical process for the precombustion removal of substantial percentages of 13 inorganic hazardous air pollutant (HAP) precursors from coal. These HAP precursors are Sb, As, Be, Cd, Cr, Cl, Co, F, Pb, Hg, Mn, Ni, and Se. Although rapid physical coal cleaning is done routinely in preparation plants, biochemical processes for removal of HAP precursors from coal potentially offer advantages of deeper cleaning, more specificity, and less coal loss. Compared to chemical processes for coal cleaning, biochemical processes potentially offer lower costs and milder process conditions. Pyrite oxidizing bacteria, most notably Thiobacillusferrooxidans, are being evaluated in this project for their ability to remove HAP precursors from U.S. coals.

  18. eQuilibrator--the biochemical thermodynamics calculator.

    PubMed

    Flamholz, Avi; Noor, Elad; Bar-Even, Arren; Milo, Ron

    2012-01-01

    The laws of thermodynamics constrain the action of biochemical systems. However, thermodynamic data on biochemical compounds can be difficult to find and is cumbersome to perform calculations with manually. Even simple thermodynamic questions like 'how much Gibbs energy is released by ATP hydrolysis at pH 5?' are complicated excessively by the search for accurate data. To address this problem, eQuilibrator couples a comprehensive and accurate database of thermodynamic properties of biochemical compounds and reactions with a simple and powerful online search and calculation interface. The web interface to eQuilibrator (http://equilibrator.weizmann.ac.il) enables easy calculation of Gibbs energies of compounds and reactions given arbitrary pH, ionic strength and metabolite concentrations. The eQuilibrator code is open-source and all thermodynamic source data are freely downloadable in standard formats. Here we describe the database characteristics and implementation and demonstrate its use.

  19. POPULATION III HYPERNOVAE

    SciTech Connect

    Smidt, Joseph; Whalen, Daniel J.; Wiggins, Brandon K.; Even, Wesley; Fryer, Chris L.; Johnson, Jarrett L.

    2014-12-20

    Population III supernovae have been of growing interest of late for their potential to directly probe the properties of the first stars, particularly the most energetic events that are visible near the edge of the observable universe. Until now, hypernovae, the unusually energetic Type Ib/c supernovae that are sometimes associated with gamma-ray bursts, have been overlooked as cosmic beacons at the highest redshifts. In this, the latest of a series of studies on Population III supernovae, we present numerical simulations of 25-50 M {sub ☉} hypernovae and their light curves done with the Los Alamos RAGE and SPECTRUM codes. We find that they will be visible at z = 10-15 to the James Webb Space Telescope and z = 4-5 to the Wide-Field Infrared Survey Telescope, tracing star formation rates in the first galaxies and at the end of cosmological reionization. If, however, the hypernova crashes into a dense shell ejected by its progenitor, it is expected that a superluminous event will occur that may be seen at z ∼ 20 in the first generation of stars.

  20. Advances in Biochemical Indices of Zooplankton Production.

    PubMed

    Yebra, L; Kobari, T; Sastri, A R; Gusmão, F; Hernández-León, S

    2017-01-01

    Several new approaches for measuring zooplankton growth and production rates have been developed since the publication of the ICES (International Council for the Exploration of the Sea) Zooplankton Methodology Manual (Harris et al., 2000). In this review, we summarize the advances in biochemical methods made in recent years. Our approach explores the rationale behind each method, the design of calibration experiments, the advantages and limitations of each method and their suitability as proxies for in situ rates of zooplankton community growth and production. We also provide detailed protocols for the existing methods and information relevant to scientists wanting to apply, calibrate or develop these biochemical indices for zooplankton production.

  1. Biochemical characterization of predicted Precambrian RuBisCO

    PubMed Central

    Shih, Patrick M.; Occhialini, Alessandro; Cameron, Jeffrey C.; Andralojc, P John; Parry, Martin A. J.; Kerfeld, Cheryl A.

    2016-01-01

    The antiquity and global abundance of the enzyme, RuBisCO, attests to the crucial and longstanding role it has played in the biogeochemical cycles of Earth over billions of years. The counterproductive oxygenase activity of RuBisCO has persisted over billions of years of evolution, despite its competition with the carboxylase activity necessary for carbon fixation, yet hypotheses regarding the selective pressures governing RuBisCO evolution have been limited to speculation. Here we report the resurrection and biochemical characterization of ancestral RuBisCOs, dating back to over one billion years ago (Gyr ago). Our findings provide an ancient point of reference revealing divergent evolutionary paths taken by eukaryotic homologues towards improved specificity for CO2, versus the evolutionary emphasis on increased rates of carboxylation observed in bacterial homologues. Consistent with these distinctions, in vivo analysis reveals the propensity of ancestral RuBisCO to be encapsulated into modern-day carboxysomes, bacterial organelles central to the cyanobacterial CO2 concentrating mechanism. PMID:26790750

  2. Biochemical characterization of predicted Precambrian RuBisCO.

    PubMed

    Shih, Patrick M; Occhialini, Alessandro; Cameron, Jeffrey C; Andralojc, P John; Parry, Martin A J; Kerfeld, Cheryl A

    2016-01-21

    The antiquity and global abundance of the enzyme, RuBisCO, attests to the crucial and longstanding role it has played in the biogeochemical cycles of Earth over billions of years. The counterproductive oxygenase activity of RuBisCO has persisted over billions of years of evolution, despite its competition with the carboxylase activity necessary for carbon fixation, yet hypotheses regarding the selective pressures governing RuBisCO evolution have been limited to speculation. Here we report the resurrection and biochemical characterization of ancestral RuBisCOs, dating back to over one billion years ago (Gyr ago). Our findings provide an ancient point of reference revealing divergent evolutionary paths taken by eukaryotic homologues towards improved specificity for CO2, versus the evolutionary emphasis on increased rates of carboxylation observed in bacterial homologues. Consistent with these distinctions, in vivo analysis reveals the propensity of ancestral RuBisCO to be encapsulated into modern-day carboxysomes, bacterial organelles central to the cyanobacterial CO2 concentrating mechanism.

  3. Stellar evolution.

    NASA Technical Reports Server (NTRS)

    Chiu, H.-Y. (Editor); Muriel, A.

    1972-01-01

    Aspects of normal stellar evolution are discussed together with evolution near the main sequence, stellar evolution from main sequence to white dwarf or carbon ignition, the structure of massive main-sequence stars, and problems of stellar stability and stellar pulsation. Other subjects considered include variable stars, white dwarfs, close binaries, novae, early supernova luminosity, neutron stars, the photometry of field horizontal-branch stars, and stellar opacity. Transport mechanisms in stars are examined together with thermonuclear reactions and nucleosynthesis, the instability problem in nuclear burning shells, stellar coalescence, and intense magnetic fields in astrophysics. Individual items are announced in this issue.

  4. Geometry Genetics and Evolution

    NASA Astrophysics Data System (ADS)

    Siggia, Eric

    2011-03-01

    Darwin argued that highly perfected organs such as the vertebrate eye could evolve by a series of small changes, each of which conferred a selective advantage. In the context of gene networks, this idea can be recast into a predictive algorithm, namely find networks that can be built by incremental adaptation (gradient search) to perform some task. It embodies a ``kinetic'' view of evolution where a solution that is quick to evolve is preferred over a global optimum. Examples of biochemical kinetic networks were evolved for temporal adaptation, temperature compensated entrainable clocks, explore-exploit trade off in signal discrimination, will be presented as well as networks that model the spatially periodic somites (vertebrae) and HOX gene expression in the vertebrate embryo. These models appear complex by the criterion of 19th century applied mathematics since there is no separation of time or spatial scales, yet they are all derivable by gradient optimization of simple functions (several in the Pareto evolution) often based on the Shannon entropy of the time or spatial response. Joint work with P. Francois, Physics Dept. McGill University. With P. Francois, Physics Dept. McGill University

  5. Gravitational Collapse and Neutrino Emission of Population III Massive Stars

    NASA Astrophysics Data System (ADS)

    Nakazato, Ken'ichiro; Sumiyoshi, Kohsuke; Yamada, Shoichi

    2006-07-01

    Population III (Pop III) stars are the first stars in the universe. They do not contain metals, and their formation and evolution may be different from that of stars of later generations. In fact, according to the theory of star formation, Pop III stars might have very massive components (~100-10000 Msolar). In this paper, we compute the spherically symmetric gravitational collapse of these Pop III massive stars. We solve the general relativistic hydrodynamics and neutrino transfer equations simultaneously, treating neutrino reactions in detail. Unlike supermassive stars (>~105 Msolar), the stars of concern in this paper become opaque to neutrinos. The collapse is simulated until after an apparent horizon is formed. We confirm that the neutrino transfer plays a crucial role in the dynamics of gravitational collapse and find also that the β-equilibration leads to a somewhat unfamiliar evolution of electron fraction. Contrary to the naive expectation, the neutrino spectrum does not become harder for more massive stars. This is mainly because the neutrino cooling is more efficient and the outer core is more massive as the stellar mass increases. Here the outer core is the outer part of the iron core falling supersonically. We also evaluate the flux of relic neutrinos from Pop III massive stars. As expected, the detection of these neutrinos is difficult for the currently operating detectors. However, if ever observed, the spectrum will enable us to obtain information on the formation history of Pop III stars. We investigate 18 models covering the mass range of 300-104 Msolar, making this study the most detailed numerical exploration of spherically symmetric gravitational collapse of Pop III massive stars. This will also serve as an important foundation for multidimensional investigations.

  6. Pseudo Class III malocclusion

    PubMed Central

    Al-Hummayani, Fadia M.

    2016-01-01

    The treatment of deep anterior crossbite is technically challenging due to the difficulty of placing traditional brackets with fixed appliances. This case report represents a none traditional treatment modality to treat deep anterior crossbite in an adult pseudo class III malocclusion complicated by severely retruded, supraerupted upper and lower incisors. Treatment was carried out in 2 phases. Phase I treatment was performed by removable appliance “modified Hawley appliance with inverted labial bow,” some modifications were carried out to it to suit the presented case. Positive overbite and overjet was accomplished in one month, in this phase with minimal forces exerted on the lower incisors. Whereas, phase II treatment was performed with fixed appliances (braces) to align teeth and have proper over bite and overjet and to close posterior open bite, this phase was accomplished within 11 month. PMID:27052290

  7. Pseudo Class III malocclusion.

    PubMed

    Al-Hummayani, Fadia M

    2016-04-01

    The treatment of deep anterior crossbite is technically challenging due to the difficulty of placing traditional brackets with fixed appliances. This case report represents a none traditional treatment modality to treat deep anterior crossbite in an adult pseudo class III malocclusion complicated by severely retruded, supraerupted upper and lower incisors. Treatment was carried out in 2 phases. Phase I treatment was performed by removable appliance "modified Hawley appliance with inverted labial bow," some modifications were carried out to it to suit the presented case. Positive overbite and overjet was accomplished in one month, in this phase with minimal forces exerted on the lower incisors. Whereas, phase II treatment was performed with fixed appliances (braces) to align teeth and have proper over bite and overjet and to close posterior open bite, this phase was accomplished within 11 month.

  8. The luminosity of Population III star clusters

    NASA Astrophysics Data System (ADS)

    DeSouza, Alexander L.; Basu, Shantanu

    2015-06-01

    We analyse the time evolution of the luminosity of a cluster of Population III protostars formed in the early Universe. We argue from the Jeans criterion that primordial gas can collapse to form a cluster of first stars that evolve relatively independently of one another (i.e. with negligible gravitational interaction). We model the collapse of individual protostellar clumps using non-axisymmetric numerical hydrodynamics simulations. Each collapse produces a protostar surrounded by a massive disc (i.e. Mdisc /M* ≳ 0.1), whose evolution we follow for a further 30-40 kyr. Gravitational instabilities result in the fragmentation and the formation of gravitationally bound clumps within the disc. The accretion of these fragments by the host protostar produces accretion and luminosity bursts on the order of 106 L⊙. Within the cluster, we show that a simultaneity of such events across several protostellar cluster members can elevate the cluster luminosity to 5-10 times greater than expected, and that the cluster spends ˜15 per cent of its star-forming history at these levels. This enhanced luminosity effect is particularly enabled in clusters of modest size with ≃10-20 members. In one such instance, we identify a confluence of burst events that raise the luminosity to nearly 1000 times greater than the cluster mean luminosity, resulting in L > 108 L⊙. This phenomenon arises solely through the gravitational-instability-driven episodic fragmentation and accretion that characterizes this early stage of protostellar evolution.

  9. Biochemical changes in the injured brain.

    PubMed

    Sahu, Seelora; Nag, Deb Sanjay; Swain, Amlan; Samaddar, Devi Prasad

    2017-02-26

    Brain metabolism is an energy intensive phenomenon involving a wide spectrum of chemical intermediaries. Various injury states have a detrimental effect on the biochemical processes involved in the homeostatic and electrophysiological properties of the brain. The biochemical markers of brain injury are a recent addition in the armamentarium of neuro-clinicians and are being increasingly used in the routine management of neuro-pathological entities such as traumatic brain injury, stroke, subarachnoid haemorrhage and intracranial space occupying lesions. These markers are increasingly being used in assessing severity as well as in predicting the prognostic course of neuro-pathological lesions. S-100 protein, neuron specific enolase, creatinine phosphokinase isoenzyme BB and myelin basic protein are some of the biochemical markers which have been proven to have prognostic and clinical value in the brain injury. While S-100, glial fibrillary acidic protein and ubiquitin C terminal hydrolase are early biomarkers of neuronal injury and have the potential to aid in clinical decision-making in the initial management of patients presenting with an acute neuronal crisis, the other biomarkers are of value in predicting long-term complications and prognosis in such patients. In recent times cerebral microdialysis has established itself as a novel way of monitoring brain tissue biochemical metabolites such as glucose, lactate, pyruvate, glutamate and glycerol while small non-coding RNAs have presented themselves as potential markers of brain injury for future.

  10. A Course in Biochemical Engineering Fundamentals (Revisited).

    ERIC Educational Resources Information Center

    Bailey, J. E.; Ollis, D. F.

    1985-01-01

    Provides: (1) a glossary of terms used in biochemical engineering; (2) a list of key developments in the field; and (3) emphases placed in 15 topic areas in a course restructured on the basis of these developments. Topic areas include enzyme kinetics/applications, genetics and microbial control, transport phenomena, and others. (JN)

  11. The Biochemical Basis of Minimal Brain Dysfunction

    ERIC Educational Resources Information Center

    Shaywitz, Sally E.; And Others

    1978-01-01

    Available from: C. V. Mosby Company 11830 Westline Industrial Drive St. Louis, Missouri 63141 The research review examines evidence suggesting a biochemical basis for minimal brain dysfunction (MBD), which includes both a relationship between MBD and metabolic abnormalities and a significant genetic influence on the disorder in children. (IM)

  12. 2009 Biochemical Conversion Platform Review Report

    SciTech Connect

    Ferrell, John

    2009-12-01

    This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the U.S. Department of Energy Biomass Program’s Biochemical Conversion platform review meeting, held on April 14-16, 2009, at the Sheraton Denver Downtown, Denver, Colorado.

  13. Biochemical Approaches to Improved Nitrogen Fixation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving symbiotic nitrogen fixation by legumes has emerged again as an important topic on the world scene due to the energy crisis and lack of access to nitrogen fertilizer in developing countries. We have taken a biochemical genomics approach to improving symbiotic nitrogen fixation in legumes. L...

  14. Survey of Biochemical Education in Japanese Universities.

    ERIC Educational Resources Information Center

    Kagawa, Yasuo

    1995-01-01

    Reports findings of questionnaires sent to faculty in charge of biochemical education in medical schools and other programs from dentistry to agriculture. Total class hours have declined since 1984. New trends include bioethics and computer-assisted learning. Tables show trends in lecture hours, lecture content, laboratory hours, core subject…

  15. Biochemical changes in the injured brain

    PubMed Central

    Sahu, Seelora; Nag, Deb Sanjay; Swain, Amlan; Samaddar, Devi Prasad

    2017-01-01

    Brain metabolism is an energy intensive phenomenon involving a wide spectrum of chemical intermediaries. Various injury states have a detrimental effect on the biochemical processes involved in the homeostatic and electrophysiological properties of the brain. The biochemical markers of brain injury are a recent addition in the armamentarium of neuro-clinicians and are being increasingly used in the routine management of neuro-pathological entities such as traumatic brain injury, stroke, subarachnoid haemorrhage and intracranial space occupying lesions. These markers are increasingly being used in assessing severity as well as in predicting the prognostic course of neuro-pathological lesions. S-100 protein, neuron specific enolase, creatinine phosphokinase isoenzyme BB and myelin basic protein are some of the biochemical markers which have been proven to have prognostic and clinical value in the brain injury. While S-100, glial fibrillary acidic protein and ubiquitin C terminal hydrolase are early biomarkers of neuronal injury and have the potential to aid in clinical decision-making in the initial management of patients presenting with an acute neuronal crisis, the other biomarkers are of value in predicting long-term complications and prognosis in such patients. In recent times cerebral microdialysis has established itself as a novel way of monitoring brain tissue biochemical metabolites such as glucose, lactate, pyruvate, glutamate and glycerol while small non-coding RNAs have presented themselves as potential markers of brain injury for future. PMID:28289516

  16. Biochemical Applications in the Analytical Chemistry Lab

    ERIC Educational Resources Information Center

    Strong, Cynthia; Ruttencutter, Jeffrey

    2004-01-01

    An HPLC and a UV-visible spectrophotometer are identified as instruments that helps to incorporate more biologically-relevant experiments into the course, in order to increase the students understanding of selected biochemistry topics and enhances their ability to apply an analytical approach to biochemical problems. The experiment teaches…

  17. Biochemical Thermodynamics under near Physiological Conditions

    ERIC Educational Resources Information Center

    Mendez, Eduardo

    2008-01-01

    The recommendations for nomenclature and tables in Biochemical Thermodynamics approved by IUBMB and IUPAC in 1994 can be easily introduced after the chemical thermodynamic formalism. Substitution of the usual standard thermodynamic properties by the transformed ones in the thermodynamic equations, and the use of appropriate thermodynamic tables…

  18. Cellular, biochemical and molecular mechanisms regulating oocyte maturation.

    PubMed

    Dekel, Nava

    2005-04-29

    The original model for regulation of oocyte maturation proposed by us in 1978 postulated that gap junction-mediated transmission of cAMP from the follicle cells to the oocyte inhibits meiosis and that luteinizing hormone (LH) terminates the flux of the follicle cAMP to the oocyte. A decrease in oocyte cAMP below inhibitory threshold occurs since oocytes lack the ability to generate sufficient amounts of cAMP to compensate for the phosphodiesterase activity. Our previous studies provided evidence to support this model. More recent studies in our laboratory were directed at identification of the cellular biochemical and molecular events initiated within rat oocytes upon the relief of cAMP inhibition. These studies: (i) identified an oocyte specific A kinase anchoring protein (AKAP) that is phosphorylated in oocytes resuming meiosis, (ii) confirmed that cdc25B governs meiosis reinitiation and demonstrated that its expression is translationally regulated, (iii) substantiated the indispensable role of proteasomal degradation at completion of the first meiotic division in a mammalian system, (iv) elucidated the role of MPF reactivation in suppressing interphase between the two meiotic divisions and (v) provided evidence that mos translation is negatively regulated by a protein kinase A (PKA)-mediated action of cAMP and is dependent on an active MPF. A detailed account on each of these findings is presented in this chapter.

  19. Title III and Cultural Diversity.

    ERIC Educational Resources Information Center

    The Title III Quarterly, 1973

    1973-01-01

    Title III projects dealing with cultural diversity in the classroom are described in this issue of the Title III Quarterly. Major articles are devoted to the following projects: Two Arts Culture Three Project, developing the crafts and music of mountain whites, blacks, and Cherokees; the Rota Bilingual Project, the Marianas District, emphasizing…

  20. SUPERSTARS III: 6-8.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Education, Raleigh.

    SUPERSTARS III is a K-8 program designed as an enrichment opportunity for self-directed learners in mathematics. The basic purpose of SUPERSTARS III is to provide the extra challenge that self-motivated students need in mathematics and to do so in a structured, long-term program that does not impinge on the normal classroom routine or the…

  1. Using dBase III.

    ERIC Educational Resources Information Center

    Evans, Janet; And Others

    1986-01-01

    Four articles on dBASE III include three on library applications: a photocopy invoicing system for interlibrary loan, a vertical file subject headings list program, and a subject index to statistical resources. Another article explains the differences between interpreters and compilers and the advantages of the Clipper compiler for dBASE III. (EM)

  2. SUPERSTARS III: 3-5.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Education, Raleigh.

    SUPERSTARS III is a K-8 program designed as an enrichment opportunity for self-directed learners in mathematics. The basic purpose of SUPERSTARS III is to provide the extra challenge that self-motivated students need in mathematics and to do so in a structured, long-term program that does not impinge on the normal classroom routine or the…

  3. Kombucha tea fermentation: Microbial and biochemical dynamics.

    PubMed

    Chakravorty, Somnath; Bhattacharya, Semantee; Chatzinotas, Antonis; Chakraborty, Writachit; Bhattacharya, Debanjana; Gachhui, Ratan

    2016-03-02

    Kombucha tea, a non-alcoholic beverage, is acquiring significant interest due to its claimed beneficial properties. The microbial community of Kombucha tea consists of bacteria and yeast which thrive in two mutually non-exclusive compartments: the soup or the beverage and the biofilm floating on it. The microbial community and the biochemical properties of the beverage have so far mostly been described in separate studies. This, however, may prevent understanding the causal links between the microbial communities and the beneficial properties of Kombucha tea. Moreover, an extensive study into the microbial and biochemical dynamics has also been missing. In this study, we thus explored the structure and dynamics of the microbial community along with the biochemical properties of Kombucha tea at different time points up to 21 days of fermentation. We hypothesized that several biochemical properties will change during the course of fermentation along with the shifts in the yeast and bacterial communities. The yeast community of the biofilm did not show much variation over time and was dominated by Candida sp. (73.5-83%). The soup however, showed a significant shift in dominance from Candida sp. to Lachancea sp. on the 7th day of fermentation. This is the first report showing Candida as the most dominating yeast genus during Kombucha fermentation. Komagateibacter was identified as the single largest bacterial genus present in both the biofilm and the soup (~50%). The bacterial diversity was higher in the soup than in the biofilm with a peak on the seventh day of fermentation. The biochemical properties changed with the progression of the fermentation, i.e., beneficial properties of the beverage such as the radical scavenging ability increased significantly with a maximum increase at day 7. We further observed a significantly higher D-saccharic acid-1,4-lactone content and caffeine degradation property compared to previously described Kombucha tea fermentations. Our

  4. Planets and their atmospheres - Origin and evolution

    NASA Astrophysics Data System (ADS)

    Lewis, J. S.; Prinn, R. G.

    The origin, evolution, and composition of the planetary atmospheres are examined in an introductory review of ground-based and in situ observations and theoretical models. Chapters are devoted to the retention of volatiles by planets; evolutionary processes (such as hydrogen loss, accretion and outgassing, dissolution, photo-condensation, reactions with planetary surfaces, biochemical transformations, and atmospheric escape); and the present characteristics of the planetary, lunar-size-object, and asteroid atmospheres. Graphs, diagrams, and tables of numerical data are provided.

  5. Magnetic interactions in CuII-LnIII cyclic tetranuclear complexes: is it possible to explain the occurrence of SMM behavior in CuII-TbIII and CuII-DyIII complexes?

    PubMed

    Hamamatsu, Takefumi; Yabe, Kazuya; Towatari, Masaaki; Osa, Shutaro; Matsumoto, Naohide; Re, Nazzareno; Pochaba, Andrzej; Mrozinski, Jerzy; Gallani, Jean-Louis; Barla, Alessandro; Imperia, Paolo; Paulsen, Carley; Kappler, Jean-Paul

    2007-05-28

    An extensive series of tetranuclear CuII2LnIII2 complexes [CuIILLnIII(hfac)2]2 (with LnIII being all lanthanide(III) ions except for the radioactive PmIII) has been prepared in order to investigate the nature of the CuII-LnIII magnetic interactions and to try to answer the following question: What makes the CuII2TbIII2 and CuII2DyIII2 complexes single molecule magnets while the other complexes are not? All the complexes within this series possess a similar cyclic tetranuclear structure, in which the CuII and LnIII ions are arrayed alternately via bridges of ligand complex (CuIIL). Regular SQUID magnetometry measurements have been performed on the series. The temperature-dependent magnetic susceptibilities from 2 to 300 K and the field-dependent magnetizations from 0 to 5 T at 2 K have been measured for the CuII2LnIII2 and NiII2LnIII2 complexes, with the NiII2LnIII2 complex containing diamagnetic NiII ions being used as a reference for the evaluation of the CuII-LnIII magnetic interactions. These measurements have revealed that the interactions between CuII and LnIII ions are very weakly antiferromagnetic if Ln=Ce, Nd, Sm, Yb, ferromagnetic if Ln=Gd, Tb, Dy, Ho, Er, Tm, and negligible if Ln=La, Eu, Pr, Lu. With the same goal of better understanding the evolution of the intramolecular magnetic interactions, X-ray magnetic circular dichroism (XMCD) has also been measured on CuII2TbIII2, CuII2DyIII2, and NiII2TbIII2 complexes, either at the L- and M-edges of the metal ions or at the K-edge of the N and O atoms. Last, the CuII2TbIII2 complex exhibiting SMM behavior has received a closer examination of its low temperature magnetic properties down to 0.1 K. These particular measurements have revealed the unusual very slow setting-up of a 3D order below 0.6 K.

  6. Low dimensional III-V compound semiconductor structures

    NASA Astrophysics Data System (ADS)

    Kobayashi, Nobuhiko P.

    2009-08-01

    Material incompatibilities among dissimilar group III-V compound semiconductors (III-V CSs) often place limits on combining epitaxial thin films, however low-dimensional epitaxial structures (e.g., quantum dots and nanowires) demonstrate coherent growth even on incompatible surfaces. First, InAs QDs grown by molecular beam epitaxy on GaAs are described. Two-dimensional to three-dimensional morphological transition, lateral size evolution and vertical alignment of InAs QDs in a single and multiple stacks will be illustrated. Second, InP nanowires grown on non-single crystalline surfaces by metal organic chemical vapor deposition are described with the view toward applications where III-V CSs are functionally integrated onto various material platforms.

  7. On the theory of the type III burst exciter

    NASA Technical Reports Server (NTRS)

    Smith, R. A.; Goldstein, M. L.; Papadopoulos, K.

    1976-01-01

    In situ satellite observations of type III burst exciters at 1 AU show that the beam does not evolve into a plateau in velocity space, contrary to the prediction of quasilinear theory. The observations can be explained by a theory that includes mode coupling effects due to excitation of the parametric oscillating two-stream instability and its saturation by anomalous resistivity. The time evolution of the beam velocity distribution is included in the analysis.

  8. Extracellular assembly and activation principles of oncogenic class III receptor tyrosine kinases.

    PubMed

    Verstraete, Kenneth; Savvides, Savvas N

    2012-11-01

    Intracellular signalling cascades initiated by class III receptor tyrosine kinases (RTK-IIIs) and their cytokine ligands contribute to haematopoiesis and mesenchymal tissue development. They are also implicated in a wide range of inflammatory disorders and cancers. Recent snapshots of RTK-III ectodomains in complex with cognate cytokines have revealed timely insights into the structural determinants of RTK-III activation, evolution and pathology. Importantly, candidate 'driver' and 'passenger' mutations that have been identified in RTK-IIIs can now be collectively mapped for the first time to structural scaffolds of the corresponding RTK-III ectodomains. Such insights will generate a renewed interest in dissecting the mechanistic effects of such mutations and their therapeutic relevance.

  9. The evolution of transcriptional regulation in eukaryotes

    NASA Technical Reports Server (NTRS)

    Wray, Gregory A.; Hahn, Matthew W.; Abouheif, Ehab; Balhoff, James P.; Pizer, Margaret; Rockman, Matthew V.; Romano, Laura A.

    2003-01-01

    Gene expression is central to the genotype-phenotype relationship in all organisms, and it is an important component of the genetic basis for evolutionary change in diverse aspects of phenotype. However, the evolution of transcriptional regulation remains understudied and poorly understood. Here we review the evolutionary dynamics of promoter, or cis-regulatory, sequences and the evolutionary mechanisms that shape them. Existing evidence indicates that populations harbor extensive genetic variation in promoter sequences, that a substantial fraction of this variation has consequences for both biochemical and organismal phenotype, and that some of this functional variation is sorted by selection. As with protein-coding sequences, rates and patterns of promoter sequence evolution differ considerably among loci and among clades for reasons that are not well understood. Studying the evolution of transcriptional regulation poses empirical and conceptual challenges beyond those typically encountered in analyses of coding sequence evolution: promoter organization is much less regular than that of coding sequences, and sequences required for the transcription of each locus reside at multiple other loci in the genome. Because of the strong context-dependence of transcriptional regulation, sequence inspection alone provides limited information about promoter function. Understanding the functional consequences of sequence differences among promoters generally requires biochemical and in vivo functional assays. Despite these challenges, important insights have already been gained into the evolution of transcriptional regulation, and the pace of discovery is accelerating.

  10. Pitfalls in the interpretation of common biochemical tests

    PubMed Central

    Ayling, R.

    2000-01-01

    This review considers some of the more common problems in the interpretation of the results of biochemical tests and, where possible, highlights ways in which errors can be identified or avoided.


Keywords: biochemical tests PMID:10684320

  11. Construction and analysis of biochemical networks

    NASA Astrophysics Data System (ADS)

    Binns, Michael; Theodoropoulos, Constantinos

    2012-09-01

    Bioprocesses are being implemented for a range of different applications including the production of fuels, chemicals and drugs. Hence, it is becoming increasingly important to understand and model how they function and how they can be modified or designed to give the optimal performance. Here we discuss the construction and analysis of biochemical networks which are the first logical steps towards this goal. The construction of a reaction network is possible through reconstruction: extracting information from literature and from databases. This can be supplemented by reaction prediction methods which can identify steps which are missing from the current knowledge base. Analysis of biochemical systems generally requires some experimental input but can be used to identify important reactions and targets for enhancing the performance of the organism involved. Metabolic flux, pathway and metabolic control analysis can be used to determine the limits, capabilities and potential targets for enhancement respectively.

  12. Biochemical correlates of neurosensory changes in weightlessness

    NASA Technical Reports Server (NTRS)

    Leach, Carolyn S.; Reschke, Millard F.

    1989-01-01

    The possible existence of a relationship between space motion sickness and chemical and biochemical variables measured in body fluids is studied. Clinical chemistry and endocrine measurements from blood and urine samples taken before and after Space Shuttle flights were analyzed along with the occurrence of SMS during flight and provocative testing before flight. Significant positive correlations were observed with serum chloride and significant negative correlations with serum phosphate, serum uric acid, and plasma thyroid stimulating hormone.

  13. Biochemical assessment of acute myocardial ischaemia.

    PubMed Central

    Perez-Cárceles, M D; Osuna, E; Vieira, D N; Martínez, A; Luna, A

    1995-01-01

    AIMS--To evaluate the efficacy of biochemical parameters in different fluids in the diagnosis of myocardial infarction of different causes, analysed after death. METHODS--The myoglobin concentration and total creatine kinase (CK) and creatine kinase MB isoenzyme (CK-MB) activities were measured in serum, pericardial fluid, and vitreous humour from seven diagnostic groups of cadavers classified according to the severity of myocardial ischaemia and cause of death. Lactate dehydrogenase (LDH) and myosin were measured only in serum and pericardial fluid, and cathepsin D only in pericardial fluid. Routine haematoxylin and eosin and acridine orange staining were used for microscopy studies of heart tissue. RESULTS--In pericardial fluid there were substantial differences between the different groups with respect to CK, CK-MB, and LDH activities and myosin concentrations. The highest values were found in cases with morphological evidence of myocardial ischaemia. CONCLUSIONS--Biochemical parameters, which reach the pericardial fluid via passive diffusion and ultrafiltration due to a pressure gradient, were thus detectable in this fluid earlier than in serum in cases with myocardial ischaemia. These biochemical parameters may be of use for ruling out myocardial ischaemia in those controversial cases in which reliable morphological findings are lacking. PMID:7745110

  14. Electronic modulation of biochemical signal generation

    NASA Astrophysics Data System (ADS)

    Gordonov, Tanya; Kim, Eunkyoung; Cheng, Yi; Ben-Yoav, Hadar; Ghodssi, Reza; Rubloff, Gary; Yin, Jun-Jie; Payne, Gregory F.; Bentley, William E.

    2014-08-01

    Microelectronic devices that contain biological components are typically used to interrogate biology rather than control biological function. Patterned assemblies of proteins and cells have, however, been used for in vitro metabolic engineering, where coordinated biochemical pathways allow cell metabolism to be characterized and potentially controlled on a chip. Such devices form part of technologies that attempt to recreate animal and human physiological functions on a chip and could be used to revolutionize drug development. These ambitious goals will, however, require new biofabrication methodologies that help connect microelectronics and biological systems and yield new approaches to device assembly and communication. Here, we report the electrically mediated assembly, interrogation and control of a multi-domain fusion protein that produces a bacterial signalling molecule. The biological system can be electrically tuned using a natural redox molecule, and its biochemical response is shown to provide the signalling cues to drive bacterial population behaviour. We show that the biochemical output of the system correlates with the electrical input charge, which suggests that electrical inputs could be used to control complex on-chip biological processes.

  15. Hydrogel-based piezoresistive biochemical microsensors

    NASA Astrophysics Data System (ADS)

    Guenther, Margarita; Schulz, Volker; Gerlach, Gerald; Wallmersperger, Thomas; Solzbacher, Florian; Magda, Jules J.; Tathireddy, Prashant; Lin, Genyao; Orthner, Michael P.

    2010-04-01

    This work is motivated by a demand for inexpensive, robust and reliable biochemical sensors with high signal reproducibility and long-term-stable sensitivity, especially for medical applications. Micro-fabricated sensors can provide continuous monitoring and on-line control of analyte concentrations in ambient aqueous solutions. The piezoresistive biochemical sensor containing a special biocompatible polymer (hydrogel) with a sharp volume phase transition in the neutral physiological pH range near 7.4 can detect a specific analyte, for example glucose. Thereby the hydrogel-based biochemical sensors are useful for the diagnosis and monitoring of diabetes. The response of the glucosesensitive hydrogel was studied at different regimes of the glucose concentration change and of the solution supply. Sensor response time and accuracy with which a sensor can track gradual changes in glucose was estimated. Additionally, the influence of various recommended sterilization methods on the gel swelling properties and on the mechano-electrical transducer of the pH-sensors has been evaluated in order to choose the most optimal sterilization method for the implantable sensors. It has been shown that there is no negative effect of gamma irradiation with a dose of 25.7 kGy on the hydrogel sensitivity. In order to achieve an optimum between sensor signal amplitude and sensor response time, corresponding calibration and measurement procedures have been proposed and evaluated for the chemical sensors.

  16. Controllability of non-linear biochemical systems.

    PubMed

    Ervadi-Radhakrishnan, Anandhi; Voit, Eberhard O

    2005-07-01

    Mathematical methods of biochemical pathway analysis are rapidly maturing to a point where it is possible to provide objective rationale for the natural design of metabolic systems and where it is becoming feasible to manipulate these systems based on model predictions, for instance, with the goal of optimizing the yield of a desired microbial product. So far, theory-based metabolic optimization techniques have mostly been applied to steady-state conditions or the minimization of transition time, using either linear stoichiometric models or fully kinetic models within biochemical systems theory (BST). This article addresses the related problem of controllability, where the task is to steer a non-linear biochemical system, within a given time period, from an initial state to some target state, which may or may not be a steady state. For this purpose, BST models in S-system form are transformed into affine non-linear control systems, which are subjected to an exact feedback linearization that permits controllability through independent variables. The method is exemplified with a small glycolytic-glycogenolytic pathway that had been analyzed previously by several other authors in different contexts.

  17. Cytokines as biochemical markers for knee osteoarthritis

    PubMed Central

    Mabey, Thomas; Honsawek, Sittisak

    2015-01-01

    Osteoarthritis (OA) is a debilitating degenerative joint disease particularly affecting weightbearing joints within the body, principally the hips and knees. Current radiographic techniques are insufficient to show biochemical changes within joint tissue which can occur many years before symptoms become apparent. The need for better diagnostic and prognostic tools is heightened with the prevalence of OA set to increase in aging and obese populations. As inflammation is increasingly being considered an important part of OAs pathophysiology, cytokines are being assessed as possible candidates for biochemical markers. Cytokines, both pro- and anti-inflammatory, as well as angiogenic and chemotactic, have in recent years been studied for relevant characteristics. Biochemical markers show promise in determination of the severity of disease in addition to monitoring of the efficacy and safety of disease-modifying OA drugs, with the potential to act as diagnostic and prognostic tools. Currently, the diagnostic power of interleukin (IL)-6 and the relationship to disease burden of IL-1β, IL-15, tumor necrosis factor-α, and vascular endothelial growth factor make these the best candidates for assessment. Grouping appropriate cytokine markers together and assessing them collectively alongside other bone and cartilage degradation products will yield a more statistically powerful tool in research and clinical applications, and additionally aid in distinguishing between OA and a number of other diseases in which cytokines are known to have an involvement. Further large scale studies are needed to assess the validity and efficacy of current biomarkers, and to discover other potential biomarker candidates. PMID:25621214

  18. [Basic biochemical processes in glaucoma progression].

    PubMed

    von Thun und Hohenstein-Blaul, N; Kunst, S; Pfeiffer, N; Grus, F H

    2015-05-01

    The term glaucoma summarizes a group of eye diseases that are accompanied by impairments of the optic nerve and related visual field deficits. An early diagnosis of glaucoma is currently not possible due to a lack of diagnostic tests; therefore, in most cases the disease is diagnosed many years after onset, which prevents an early therapy. The known risk factors for the development and progression of glaucomatous optic neuropathy comprise elevated intraocular pressure and a broad range of pressure fluctuations as well as lipometabolic disorders, genetic factor and diabetes. The consequences include the induction of anti-inflammatory proteins, elevated levels of oxidative stress and the destruction of retinal ganglion cells. Changes in the autoantibody repertoire have also been observed in the course of the disease. Basic ophthalmological research therefore focuses on the investigation of basic biochemical processes in the course of the disease. A better understanding of physiological and biochemical events is sought in order to develop new and more sensitive diagnostic options and to allow more targeted therapeutic measures. The understanding of biochemical processes allows a better insight into glaucoma progression to be gained, which will lead to improvements in diagnosis and therapy.

  19. Explorations into Chemical Reactions and Biochemical Pathways.

    PubMed

    Gasteiger, Johann

    2016-12-01

    A brief overview of the work in the research group of the present author on extracting knowledge from chemical reaction data is presented. Methods have been developed to calculate physicochemical effects at the reaction site. It is shown that these physicochemical effects can quite favourably be used to derive equations for the calculation of data on gas phase reactions and on reactions in solution such as aqueous acidity of alcohols or carboxylic acids or the hydrolysis of amides. Furthermore, it is shown that these physicochemical effects are quite effective for assigning reactions into reaction classes that correspond to chemical knowledge. Biochemical reactions constitute a particularly interesting and challenging task for increasing our understanding of living species. The BioPath.Database is a rich source of information on biochemical reactions and has been used for a variety of applications of chemical, biological, or medicinal interests. Thus, it was shown that biochemical reactions can be assigned by the physicochemical effects into classes that correspond to the classification of enzymes by the EC numbers. Furthermore, 3D models of reaction intermediates can be used for searching for novel enzyme inhibitors. It was shown in a combined application of chemoinformatics and bioinformatics that essential pathways of diseases can be uncovered. Furthermore, a study showed that bacterial flavor-forming pathways can be discovered.

  20. Stoichiometric network theory for nonequilibrium biochemical systems.

    PubMed

    Qian, Hong; Beard, Daniel A; Liang, Shou-dan

    2003-02-01

    We introduce the basic concepts and develop a theory for nonequilibrium steady-state biochemical systems applicable to analyzing large-scale complex isothermal reaction networks. In terms of the stoichiometric matrix, we demonstrate both Kirchhoff's flux law sigma(l)J(l)=0 over a biochemical species, and potential law sigma(l) mu(l)=0 over a reaction loop. They reflect mass and energy conservation, respectively. For each reaction, its steady-state flux J can be decomposed into forward and backward one-way fluxes J = J+ - J-, with chemical potential difference deltamu = RT ln(J-/J+). The product -Jdeltamu gives the isothermal heat dissipation rate, which is necessarily non-negative according to the second law of thermodynamics. The stoichiometric network theory (SNT) embodies all of the relevant fundamental physics. Knowing J and deltamu of a biochemical reaction, a conductance can be computed which directly reflects the level of gene expression for the particular enzyme. For sufficiently small flux a linear relationship between J and deltamu can be established as the linear flux-force relation in irreversible thermodynamics, analogous to Ohm's law in electrical circuits.

  1. Genetic and Biochemical Biomarkers in Canine Glaucoma.

    PubMed

    Graham, K L; McCowan, C; White, A

    2017-03-01

    In many health-related fields, there is great interest in the identification of biomarkers that distinguish diseased from healthy individuals. In addition to identifying the diseased state, biomarkers have potential use in predicting disease risk, monitoring disease progression, evaluating treatment efficacy, and informing pathogenesis. This review details the genetic and biochemical markers associated with canine primary glaucoma. While there are numerous molecular markers (biochemical and genetic) associated with glaucoma in dogs, there is no ideal biomarker that allows early diagnosis and/or identification of disease progression. Genetic mutations associated with canine glaucoma include those affecting ADAMTS10, ADAMTS17, Myocilin, Nebulin, COL1A2, RAB22A, and SRBD1. With the exception of Myocilin, there is very limited crossover in genetic biomarkers identified between human and canine glaucomas. Mutations associated with canine glaucoma vary between and within canine breeds, and gene discoveries therefore have limited overall effects as a screening tool in the general canine population. Biochemical markers of glaucoma include indicators of inflammation, oxidative stress, serum autoantibodies, matrix metalloproteinases, tumor necrosis factor-α, and transforming growth factor-β. These markers include those that indicate an adaptive or protective response, as well as those that reflect the damage arising from oxidative stress.

  2. PREFACE: Quantum Optics III

    NASA Astrophysics Data System (ADS)

    Orszag, M.; Retamal, J. C.; Saavedra, C.; Wallentowitz, S.

    2007-06-01

    All the 50 years of conscious pondering did not bring me nearer to an answer to the question `what is light quanta?'. Nowadays, every rascal believes, he knows it, however, he is mistaken. (A Einstein, 1951 in a letter to M Besso) Quantum optics has played a key role in physics in the last several decades. On the other hand, in these early decades of the information age, the flow of information is becoming more and more central to our daily life. Thus, the related fields of quantum information theory as well as Bose-Einstein condensation have acquired tremendous importance in the last couple of decades. In Quantum Optics III, a fusion of these fields appears in a natural way. Quantum Optics III was held in Pucón, Chile, in 27-30 of November, 2006. This beautiful location in the south of Chile is near the lake Villarrica and below the snow covered volcano of the same name. This fantastic environment contributed to a relaxed atmosphere, suitable for informal discussion and for the students to have a chance to meet the key figures in the field. The previous Quantum Optics conferences took place in Santiago, Chile (Quantum Optics I, 2000) and Cozumel, Mexico (Quantum Optics II, 2004). About 115 participants from 19 countries attended and participated in the meeting to discuss a wide variety of topics such as quantum-information processing, experiments related to non-linear optics and squeezing, various aspects of entanglement including its sudden death, correlated twin-photon experiments, light storage, decoherence-free subspaces, Bose-Einstein condensation, discrete Wigner functions and many more. There was a strong Latin-American participation from Argentina, Brazil, Chile, Colombia, Peru, Uruguay, Venezuela and Mexico, as well as from Europe, USA, China, and Australia. New experimental and theoretical results were presented at the conference. In Latin-America a quiet revolution has taken place in the last twenty years. Several groups working in quantum optics and

  3. Silent evolution

    PubMed Central

    OSAWA, Syozo; SU, Zhi-Hui; NISHIKAWA, Masaaki; TOMINAGA, Osamu

    2016-01-01

    Phylogenetic analyses using mitochondrial DNA sequences of several kinds of beetles have shown that their evolution included a silent stage in which no morphological changes took place. We thus propose a new category of evolutionary process called “silent evolution”. PMID:27840392

  4. Security Evolution.

    ERIC Educational Resources Information Center

    De Patta, Joe

    2003-01-01

    Examines how to evaluate school security, begin making schools safe, secure schools without turning them into fortresses, and secure schools easily and affordably; the evolution of security systems into information technology systems; using schools' high-speed network lines; how one specific security system was developed; pros and cons of the…

  5. Art & Evolution

    ERIC Educational Resources Information Center

    Terry, Mark

    2005-01-01

    In this article, the author presents a two-week evolution unit for his biology class. He uses Maria Sybilla Merian (1647-1717) as an example of an Enlightenment mind at work--in this case a woman recognized as one of the great artists and natural scientists of her time. Her representations of butterflies, caterpillars and their pupae, and the…

  6. The Use of Item Analysis for Improvement of Biochemical Teaching

    ERIC Educational Resources Information Center

    Nagata, Ryoichi

    2004-01-01

    Item analysis was used to find out which biochemical explanations need to be improved in biochemical teaching, not which items are to be discarded, improved, or reusable in biochemical examinations. The analysis revealed the basic facts of which less able students had more misunderstanding than able students. Identifying these basic facts helps…

  7. Experimental evolution in biofilm populations

    PubMed Central

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  8. Viking Phase III

    NASA Technical Reports Server (NTRS)

    1978-01-01

    VIKING PHASE III - With the incredible success of the Viking missions on Mars, mission operations have progressed though a series of phases - each being funded as mission success dictated its potential. The Viking Primary Mission phase was concluded in November, 1976, when the reins were passed on to the second phase - the Viking Extended Mission. The Extended Mission successfully carried spacecraft operations through the desired period of time needed to provided a profile of a full Martian year, but would have fallen a little short of connecting and overlapping a full Martian year of Viking operations which scientists desired as a means of determining the degree of duplicity in the red planet's seasons - at least for the summer period. Without this continuation of spacecraft data acquisitions to and beyond the seasonal points when the spacecraft actually began their Mars observations, there would be no way of knowing whether the changing environmental values - such as temperatures and winds atmospheric dynamics and water vapor, surface thermal dynamics, etc. - would match up with those acquired as the spacecraft began investigations during the summer and fall of 1976. This same broad interest can be specifically pursued at the surface - where hundreds of rocks, soil drifts and other features have become extremely familiar during long-term analysis. This picture was acquired on the 690th Martian day of Lander 1 operations - 4009th picture sequence commanded of the two Viking Landers. As such, it became the first picture acquired as the third phase of Viking operations got under way - the Viking Continuation Mission. Between the start of the Continuation Mission in April, 1978, until spacecraft operations are concluded in November, the landers will acquire an additional 200 pictures. These will be used to monitor the two landscaped for the surface changes. All four cameras, two on Lander 1 and two on Lander 2, continue to operate perfectly. Both landers will also

  9. Cranial mononeuropathy III - diabetic type

    MedlinePlus

    ... diabetic type of cranial mononeuropathy III is a complication of diabetes . It causes double vision and eyelid drooping . ... Cooper ME, Vinik AI, Plutzky J, Boulton AJM. Complications of diabetes mellitus. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg ...

  10. Glycogen storage disease type III in the Irish population.

    PubMed

    Crushell, Ellen; Treacy, Eileen P; Dawe, J; Durkie, M; Beauchamp, Nicholas J

    2010-12-01

    Glycogen storage disease type III (GSD III) results from mutations of the AGL gene encoding the glycogen debrancher enzyme. The disease has clinical and biochemical heterogeneity reflecting the severity of the AGL mutations. We sought to characterise the molecular defects in our cohort of Irish patients with GSD III. Fifteen patients from eight unrelated Irish families were identified: six males and nine females. The age ranged from 2-39 years old, and all presented in the first 3 years of life. Four patients (of three families) had mild disease with hepatomegaly, mild hypoglycaemia and normal creatine kinase (CK) levels. Five families had more severe disease, with liver and skeletal muscle involvement and elevated CK. Eleven different mutations were identified amongst the eight families. Of the 11, six were novel: p.T512fs, p.S736fs, p.A1400fs, p.K1407fs, p.Y519X and p.D627Y. The family homozygous for p.A1400fs had the most severe phenotype (early-onset hypoglycaemia, massive hepatomegaly, myopathy and hypertrophic cardiomyopathy before age 2 years), which was not halted by aggressive carbohydrate and protein supplementation. Conversely, the only missense mutation identified in the cohort, p.D627Y, was associated with a mild phenotype. The phenotypic diversity in our GSD III cohort is mirrored by the allelic heterogeneity. We describe two novel null mutations in exon 32 in two families with severe GSD III resistant to current treatment modalities. Knowledge of the specific mutations segregating in this cohort may allow for the development of new therapeutic interventions.

  11. Cherenkov imaging and biochemical sensing in vivo during radiation therapy

    NASA Astrophysics Data System (ADS)

    Zhang, Rongxiao

    While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at some point during their cancer management, there is a constant challenge to ensure optimal treatment efficiency is achieved with maximal tumor to normal tissue therapeutic ratio. To achieve this, the treatment process as well as biological information affecting the treatment should ideally be effective and directly derived from the delivery of radiation to the patient. The value of Cherenkov emission imaging was examined here, primarily for visualization of treatment monitoring and then secondarily for Cherenkov-excited luminescence for tissue biochemical sensing within tissue. Through synchronized gating to the short radiation pulses of a linear accelerator (200Hz & 3 micros pulses), and applying a gated intensified camera for imaging, the Cherenkov radiation can be captured near video frame rates (30 frame per sec) with dim ambient room lighting. This procedure, sometimes termed Cherenkoscopy, is readily visualized without affecting the normal process of external beam radiation therapy. With simulation, phantoms and clinical trial data, each application of Cherenkoscopy was examined: i) for treatment monitoring, ii) for patient position monitoring and motion tracking, and iii) for superficial dose imaging. The temporal dynamics of delivered radiation fields can easily be directly imaged on the patient's surface. Image registration and edge detection of Cherenkov images were used to verify patient positioning during treatment. Inter-fraction setup accuracy and intra-fraction patient motion was detectable to better than 1 mm accuracy. Cherenkov emission in tissue opens up a new field of biochemical sensing within the tissue environment, using luminescent agents which can be activated by this light. In the first study of

  12. Mechanism and evolution of hypoxia-tolerance in humans.

    PubMed

    Hochachka, P W

    1998-04-01

    To physiologists, the term 'adaptation' usually refers to any trait that is considered advantageous; evolutionary biologists require a more rigorous definition (restricting it to traits arising and maintained under selection). By their definition, many physiological traits may merely reflect inheritance passed on through lineage. In considering the evolution of tolerance to reduced oxygen availability, we examined the issue (of true adaptations versus simple inheritance) in pinnipeds (the two dominant groups, phocids and otariids, with varying diving capacities) and in human lineages exposed for varying generational periods to hypobaric hypoxia. Basic principles of the evolution of complex physiological systems first emerged from an analysis of the diving response. We then analyzed human responses to hypobaric hypoxia in three different lineages: lowlanders, Andean natives (Quechuas) and Himalayan natives (Sherpas). As in the pinniped example, we found 'conservative' and 'adaptable' physiological characters involved in human responses to hypoxia. Conservative characters are clearly dominant and are too numerous to outline in detail; three examples are haemoglobin oxygen-affinities, the organization of muscle into different fibre types and the brain's almost exclusive preference for glucose as a fuel. Most notably, we also found evidence for 'adaptable' characters at all levels of organization examined. At the whole-body level in Quechuas and Sherpas, we found (i) that maximum aerobic and anaerobic exercise capacities were down-regulated, (ii) that the acute effect of hypoxia (making up the energy deficit due to oxygen lack; i.e. the Pasteur effect) expected from lowlanders was blunted, and (iii) that acclimation effects were also attenuated. The biochemical behaviour of skeletal muscles was consistent with lowered reliance on glycolytic contributions to energy supply, thus improving the yield of ATP per mole of carbon fuel utilized. Heart adaptations also seemed to

  13. Microfluidic Compartmentalized Directed Evolution

    PubMed Central

    Paegel, Brian M.; Joyce, Gerald F.

    2010-01-01

    Summary Directed evolution studies often make use of water-in-oil compartments, which conventionally are prepared by bulk emulsification, a crude process that generates non-uniform droplets and can damage biochemical reagents. A microfluidic emulsification circuit was devised that generates uniform water-in-oil droplets (21.9 ± 0.8 μm radius) with high throughput (107–108 droplets per hour). The circuit contains a radial array of aqueous flow nozzles that intersect a surrounding oil flow channel. This device was used to evolve RNA enzymes with RNA ligase activity, selecting enzymes that could resist inhibition by neomycin. Each molecule in the population had the opportunity to undergo 108-fold selective amplification within its respective compartment. Then the progeny RNAs were harvested and used to seed new compartments. During five rounds of this procedure, the enzymes acquired mutations that conferred resistance to neomycin and caused some enzymes to become dependent on neomycin for optimal activity. PMID:20659684

  14. Mechanisms of Ovarian Cancer Metastasis: Biochemical Pathways

    PubMed Central

    Nakayama, Kentaro; Nakayama, Naomi; Katagiri, Hiroshi; Miyazaki, Kohji

    2012-01-01

    Ovarian cancer is the most lethal gynecologic malignancy. Despite advances in chemotherapy, the five-year survival rate of advanced ovarian cancer patients with peritoneal metastasis remains around 30%. The most significant prognostic factor is stage, and most patients present at an advanced stage with peritoneal dissemination. There is often no clearly identifiable precursor lesion; therefore, the events leading to metastatic disease are poorly understood. This article reviews metastatic suppressor genes, the epithelial-mesenchymal transition (EMT), and the tumor microenvironment as they relate to ovarian cancer metastasis. Additionally, novel chemotherapeutic agents targeting the metastasis-related biochemical pathways are discussed. PMID:23109879

  15. Sampling rare switching events in biochemical networks.

    PubMed

    Allen, Rosalind J; Warren, Patrick B; Ten Wolde, Pieter Rein

    2005-01-14

    Bistable biochemical switches are widely found in gene regulatory networks and signal transduction pathways. Their switching dynamics are difficult to study, however, because switching events are rare, and the systems are out of equilibrium. We present a simulation method for predicting the rate and mechanism of the flipping of these switches. We apply it to a genetic switch and find that it is highly efficient. The path ensembles for the forward and reverse processes do not coincide. The method is widely applicable to rare events and nonequilibrium processes.

  16. [Chronic fatigue syndrome: biochemical examination of blood].

    PubMed

    Hakariya, Yukiko; Kuratsune, Hirohiko

    2007-06-01

    Though patients with chronic fatigue syndrome (CFS) have lots of complaints, abnormal findings cannot be detected by biochemical screening tests. However, some specialized blood tests have revealed neuroendocrine immune axis abnormalities, which is closely associated with each other. Recent studies indicate that CFS can be understood as a special condition based on abnormality of the psycho-neuro-endocrino-immunological system, with the distinguishing feature of CFS seeming to be the secondary brain dysfunction caused by several cytokines and/or autoantibodies. In this paper, we summarize these abnormalities found in CFS and show the neuro-molecular mechanism leading to chronic fatigue.

  17. Azoospermia: clinical, hormonal, and biochemical investigation.

    PubMed

    Papadimas, J; Papadopoulou, F; Ioannidis, S; Spanos, E; Tarlatzis, B; Bontis, J; Mantalenakis, S

    1996-01-01

    The aim of this study was to evaluate the clinical, hormonal and biochemical characteristics of infertile men with azoospermia. A total of 187 azoospermic out of 2610 infertile men (7.2%) were studied. Mean testicular volume and basal plasma levels of FSH were the most useful parameters concerning the evaluation of azoospermia. Basal plasma levels of LH and T were useful only in azoospermic men with hypogonadism, whereas plasma PRL levels, semen volume, and seminal plasma fructose levels were not found to be of common use except in selected cases.

  18. Biochemical Disincentives to Fertilizing Cellulosic Ethanol Crops

    NASA Astrophysics Data System (ADS)

    Gallagher, M. E.; Hockaday, W. C.; Snapp, S.; McSwiney, C.; Baldock, J.

    2010-12-01

    Corn grain biofuel crops produce the highest yields when the cropping ecosystem is not nitrogen (N)-limited, achieved by application of fertilizer. There are environmental consequences for excessive fertilizer application to crops, including greenhouse gas emissions, hypoxic “dead zones,” and health problems from N runoff into groundwater. The increase in corn acreage in response to demand for alternative fuels (i.e. ethanol) could exacerbate these problems, and divert food supplies to fuel production. A potential substitute for grain ethanol that could reduce some of these impacts is cellulosic ethanol. Cellulosic ethanol feedstocks include grasses (switchgrass), hardwoods, and crop residues (e.g. corn stover, wheat straw). It has been assumed that these feedstocks will require similar N fertilization rates to grain biofuel crops to maximize yields, but carbohydrate yield versus N application has not previously been monitored. We report the biochemical stocks (carbohydrate, protein, and lignin in Mg ha-1) of a corn ecosystem grown under varying N levels. We measured biochemical yield in Mg ha-1 within the grain, leaf and stem, and reproductive parts of corn plants grown at seven N fertilization rates (0-202 kg N ha-1), to evaluate the quantity and quality of these feedstocks across a N fertilization gradient. The N fertilization rate study was performed at the Kellogg Biological Station-Long Term Ecological Research Site (KBS-LTER) in Michigan. Biochemical stocks were measured using 13C nuclear magnetic resonance spectroscopy (NMR), combined with a molecular mixing model (Baldock et al. 2004). Carbohydrate and lignin are the main biochemicals of interest in ethanol production since carbohydrate is the ethanol feedstock, and lignin hinders the carbohydrate to ethanol conversion process. We show that corn residue carbohydrate yields respond only weakly to N fertilization compared to grain. Grain carbohydrate yields plateau in response to fertilization at

  19. Physiological and biochemical changes with Vamana procedure

    PubMed Central

    Gupta, Bharti; Mahapatra, Sushil C.; Makhija, Renu; Kumar, Adarsh; Jirankalgikar, Nikhil M.; Padhi, Madan M.; Devalla, Ramesh Babu

    2012-01-01

    Vamana Karma (therapeutic emesis) primarily a Samshodhana Karma (purification procedure) is one of the five Pradhana Karmas (chief procedures) of Panchakarma. It is mentioned in Ayurvedic texts that a person after Samyak Vamana (proper Vamana) experiences lightness of the body, Hrit (precordium), Kantha (throat/voice), and Shirah (head) and weakness. This procedure is effectively used in healthy and ailing persons for purification of body and extraction of Doshas (especially Kapha) in Ayurvedic system. It has been found worth to observe the physiological and biochemical changes during Vamana and after the procedure to understand the effect/safety margins of the procedure in healthy volunteers. PMID:23723640

  20. [Optical detection system for micro biochemical analyses].

    PubMed

    Li, Feng; Wu, Yi-hui; Zhao, Hua-bing; Ju, Hui

    2005-04-01

    For the need of biochemical chip, which consumes fewer specimens and is easy to integrate with micro-fluid chip, two kinds of spectrophotometric analysis methods are described in the present paper. Both the direct detection method and evanescent wave detection method are used in the experiments with visible light (460-800 nm). The experimental results proved that the direct detection is simple and evident; on the other hand the evanescent wave detection method consumes much less reagent and is easy to integrate with microchips.

  1. An integrative top-down and bottom-up qualitative model construction framework for exploration of biochemical systems.

    PubMed

    Wu, Zujian; Pang, Wei; Coghill, George M

    Computational modelling of biochemical systems based on top-down and bottom-up approaches has been well studied over the last decade. In this research, after illustrating how to generate atomic components by a set of given reactants and two user pre-defined component patterns, we propose an integrative top-down and bottom-up modelling approach for stepwise qualitative exploration of interactions among reactants in biochemical systems. Evolution strategy is applied to the top-down modelling approach to compose models, and simulated annealing is employed in the bottom-up modelling approach to explore potential interactions based on models constructed from the top-down modelling process. Both the top-down and bottom-up approaches support stepwise modular addition or subtraction for the model evolution. Experimental results indicate that our modelling approach is feasible to learn the relationships among biochemical reactants qualitatively. In addition, hidden reactants of the target biochemical system can be obtained by generating complex reactants in corresponding composed models. Moreover, qualitatively learned models with inferred reactants and alternative topologies can be used for further web-lab experimental investigations by biologists of interest, which may result in a better understanding of the system.

  2. Digital and analog chemical evolution.

    PubMed

    Goodwin, Jay T; Mehta, Anil K; Lynn, David G

    2012-12-18

    created by modification of a nucleic acid backbone and show how it has exploited the digital-like base pairing for reversible polymer construction and information transfer. We further review how these lessons have been extended to the complex folding landscapes of templated peptide assembly. These insights have allowed for the construction of molecular hybrids of each biopolymer class and made possible the reimagining of chemical evolution. Such elaboration of biopolymer chimeras has already led to applications in therapeutics and diagnostics, to the construction of novel nanostructured materials, and toward orthogonal biochemical pathways that expand the evolution of existing biochemical systems. The ability to look beyond the primordial emergence of the ribosome may allow us to better define the origins of chemical evolution, to extend its horizons beyond the biology of today and ask whether evolution is an inherent property of matter unbounded by physical limitations imposed by our planet's diverse environments.

  3. Impact analysis of Minuteman III Payload Transporter Type III

    SciTech Connect

    Stirbis, P.P.

    1993-12-01

    An analysis of the impact of the Minuteman III Payload Transporter Type III into a nonyielding target at 46 m.p.h. and 30 m.p.h., and into a yielding target at 46 m.p.h. is presented. The analysis considers the structural response of the tiedown system which secures the Minuteman III re-entry system to the floor of the payload transporter. A finite element model of the re-entry system, its tiedown system, which includes tie-rods and shear pins, and the pallet plate which is attached to the transporter floating plate, was constructed. Because accelerations of the payload transporter are not known, acceleration data from one-quarter scale testing of the Safe Secure Trailer was used to investigate the response of the tiedown system. These accelerations were applied to the pallet plate. The ABAQUS computer code was used to predict the forces in the members of the tiedown system.

  4. Dissociation of cerium(III) and neodymium(III) phthalocyanines

    NASA Astrophysics Data System (ADS)

    Lomova, T. N.

    2015-07-01

    The kinetics of dissociation of phthalocyanine complexes with cerium(III) and neodymium(III) (X)LnPc (X = Cl-, Br-, AcO-) under the action of acetic acid in ethanol with isolation of the macrocyclic ligand depending on the temperature was studied. The kinetic equations with the numerical values of rate constants, activation parameters, and the stoichiometric mechanisms with the limiting simple reaction between the nonionized AcOH molecule and (phthalocyaninato)lanthanide(III) in the axially coordinated ((X)LnPc, cerium complexes) or axially ionized ([(AcOH)LnPc]+X-, neodymium complexes) state were derived by solving the direct and inverse problems. As shown by a comparative analysis of quantitative kinetic data, the state is determined by the electronic structure of the metal cation and the mutual effect of the axial and equatorial ligands in the first coordination sphere.

  5. Biochemical responses of the Skylab crewman

    NASA Technical Reports Server (NTRS)

    Leach, C. S.; Rambaut, P. C.

    1974-01-01

    The biochemical investigations of the Skylab crewmen were designed to study the physiological changes that were observed on flight crews returning from previous space flight missions as well as to study those changes expected to result from prolonged weightless exposure. These studies can be divided into two broad categories. One category included routine blood studies similar to those used in clinical medical practice. The second included research-type endocrine analyses used to investigate more thoroughly the metabolic/endocrine responses to the space flight environment. The premission control values indicated that all Skylab crewmen were healthy and were free from biochemical abnormalities. The routine results during and after flight showed slight but significant changes in electrolytes, glucose, total protein, osmolality, uric acid, cholesterol, and creatinine. Plasma hormal changes included adrenocorticotrophic hormone, cortisol, angiotensin I, aldosterone, insulin, and thyroxine. The 24-hour urine analyses results revealed increased excretion of cortisol, catecholamines, antidiuretic hormone, and aldosterone as well as excretion of significant electrolyte and uric acid during the Skylab flights.

  6. [Biochemical principles of early saturnism recognition].

    PubMed

    Tsimakuridze, M P; Mansuradze, E A; Zurashvili, D G; Tsimakuridze, M P

    2009-03-01

    The aim of the work is to determine the major sensitive criteria of biochemical indicators that allow timely discovery of negative influence of lead on organism and assist in early diagnosis of primary stages of saturnism. The workers of Georgian typographies, performing technological processes of letterpress printing were observed. Professional groups having contact with lead aerosols (main group of 66 people) and the workers of the same typography not being in touch with the poison (control group of 24 people) were studied. It was distinguished that, protracted professional contact with lead causes moderate increase of lead, coproporphyrin and DALA in daily urine in most cases; it is more clearly evidenced in the professional groups of lead smelters and lino operators and less clearly among typesetter and printers. Upon the checkup of people, having a direct contact with lead, biochemical analysis of urine should be given a preference, especially the determination of quantitative content of lead and coproporphyrin in urine with the aim of revealing the lead carrier, which is one of the first signals for occupational lookout and medical monitoring of the similar contingent.

  7. Pheochromocytoma-paraganglioma: Biochemical and genetic diagnosis.

    PubMed

    Cano Megías, Marta; Rodriguez Puyol, Diego; Fernández Rodríguez, Loreto; Sención Martinez, Gloria Lisette; Martínez Miguel, Patricia

    Pheochromocytomas and paragangliomas are tumours derived from neural crest cells, which can be diagnosed by biochemical measurement of metanephrine and methoxytyramine. Advances in genetic research have identified many genes involved in the pathogenesis of these tumours, suggesting that up to 35-45% may have an underlying germline mutation. These genes have a singular transcriptional signature and can be grouped into 2 clusters (or groups): cluster 1 (VHL and SHDx), involved in angiogenesis and hypoxia pathways; and cluster 2 (MEN2 and NF1), linked to the kinase signalling pathway. In turn, these genes are associated with a characteristic biochemical phenotype (noradrenergic and adrenergic), and clinical features (location, biological behaviour, age of presentation, etc.) in a large number of cases. Early diagnosis of these tumours, accompanied by a correct genetic diagnosis, should eventually become a priority to enable better treatment, early detection of complications, proper screening of family members and related tumours, as well as an improvement in the overall prognosis of these patients.

  8. Biochemical effects of oral sodium phosphate.

    PubMed

    DiPalma, J A; Buckley, S E; Warner, B A; Culpepper, R M

    1996-04-01

    Our objective was to monitor serum and urine biochemical changes after oral sodium phosphate cleansing in a prospectively designed study. The study subjects were seven healthy, asymptomatic adults. Sodium phosphate 45 ml diluted in 45 ml water was given orally at baseline and 12 hr later. Calcium, ionized calcium, phosphorus, sodium, potassium, creatinine, and PTH were analyzed at 2, 4, 6, 9, 12, 14, 16, 18, 21 and 24 hr after the first challenge. Urinary calcium, phosphorus, sodium, potassium, and cyclic AMP were analyzed at baseline and every 2 hr after oral sodium phosphate. Blood pressure, pulse, and respiratory rate were recorded every 2 hr and symptom questionnaires using visual analog scales were completed. A marked rise in phosphorus (peak range 3.6-12.4 mg/dl, P < 0.001) and falls in calcium (P < 0.001) and ionized calcium (P < 0.001) were seen. Rises seen in PTH and urinary cAMP confirmed the physiologic significance of the biochemical effect. There were no significant changes in other serum and urine laboratory or clinical assessments. Reported significant symptoms included bloating, cramps, abdominal pain, and nausea. Significant hypocalcemia and hyperphosphatemia after oral sodium phosphate raises concern about its use in normal individuals. Oral sodium phosphate should not be administered in patients with cardiopulmonary, renal, or hepatic disease.

  9. Biochemical basis for the biological clock

    NASA Technical Reports Server (NTRS)

    Morre, D. James; Chueh, Pin-Ju; Pletcher, Jake; Tang, Xiaoyu; Wu, Lian-Ying; Morre, Dorothy M.

    2002-01-01

    NADH oxidases at the external surface of plant and animal cells (ECTO-NOX proteins) exhibit stable and recurring patterns of oscillations with potentially clock-related, entrainable, and temperature-compensated period lengths of 24 min. To determine if ECTO-NOX proteins might represent the ultradian time keepers (pacemakers) of the biological clock, COS cells were transfected with cDNAs encoding tNOX proteins having a period length of 22 min or with C575A or C558A cysteine to alanine replacements having period lengths of 36 or 42 min. Here we demonstrate that such transfectants exhibited 22, 36, or 40 to 42 h circadian patterns in the activity of glyceraldehyde-3-phosphate dehydrogenase, a common clock-regulated protein, in addition to the endogenous 24 h circadian period length. The fact that the expression of a single oscillatory ECTO-NOX protein determines the period length of a circadian biochemical marker (60 X the ECTO-NOX period length) provides compelling evidence that ECTO-NOX proteins are the biochemical ultradian drivers of the cellular biological clock.

  10. The effects of L-tryptophan and melatonin on selected biochemical parameters in patients with steatohepatitis.

    PubMed

    Cichoz-Lach, H; Celinski, K; Konturek, P C; Konturek, S J; Slomka, M

    2010-10-01

    Nonalcoholic fatty liver disease is the most common chronic liver disease and nonalcocholic steatohepatitis (NASH) is its advanced form. Oxidative stress and hepatocyte apoptosis may be involved in pathogenesis of NASH and particularly in progress of NASH to liver fibrosis and cirrhosis, which are initiated by the inflammation and which promote the progress of the disease. The aim of this study was to evaluate the effects of melatonin and L-tryptophan on selected biochemical parameters of blood in patients with NASH. Forty five patients with NASH, confirmed by histopathological examination of liver biopsy samples, were admitted to the study. They were divided into three groups (I, II and III). The first group (group I, n=15) received preparation Essentiale forte 3 times a day and tryptophan 500 mg twice daily for 4 weeks. In the second group (group II, n=15), Essentiale forte three times a day was administered with melatonin 5 mg applied twice a day for 4 weeks. The third group (group III, n=15) received only Essentiale forte with placebo three times a day for 4 weeks. After four-week treatment we found statistically significant reduction in GGTP, triglycerides and proinflammatory cytokine levels in the melatonin-treated (group I) and the L-tryptophan-treated patients (group II). Plasma level of melatonin was significantly elevated in groups treated with tryptophan (group I) and melatonin (group II), but remained unchanged in placebo-treated group (group III). Among patients from the third group (treated with placebo) no statistically significant differences in the measured biochemical parameters were observed. The present study suggests that melatonin and tryptophan have the significant impact on the reduction in plasma levels of proinflammatory cytokines and may be useful in the treatment of patients with NASH.

  11. Evaluation of Nutritional Biochemical Parameters in Haemodialysis Patients over a Ten-year Period

    PubMed Central

    Alfonso, AIQ; Castillo, RF; Jimenez, FJ Gomez; Negrillo, AM Nuñez

    2015-01-01

    ABSTRACT Aim: Protein-energy malnutrition as well as systemic inflammation and metabolic disorders are common in patients with chronic kidney failure who require renal replacement therapy (haemodialysis). Such malnutrition is a factor that significantly contributes to their morbidity and mortality. This study evaluated the nutritional status of haemodialysis patients by assessing biochemical and anthropometric parameters in order to determine whether these patients suffered disorders reflecting nutritional deterioration directly related to time on haemodialysis. Subjects and Method: This research comprised 90 patients of both genders with chronic kidney failure, who regularly received haemodialysis at our unit over a period of ten years. The patients' blood was tested quarterly for plasma albumin, total cholesterol and total proteins, and tested monthly for transferrin. The patients' weight, height and body mass index (BMI) were monitored. Body mass index was calculated using the formula: weight (kg)/height (m2) and classified in one of the following categories defined in the World Health Organization (WHO) Global Database on Body Mass Index: (i) underweight [BMI < 18.50], (ii) normal [BMI 18.50 – 24.99], (iii) overweight [BMI 25 – 29.99], (iv) obese [BMI ≥ 30]. Results: In the ten-year period of the study, the patients experienced a substantial decline in their biochemical parameters. Nevertheless, their BMI did not show any significant changes despite the patients' state of malnutrition. Conclusions: The prevalence of malnutrition in haemodialysis patients was evident. Nevertheless, the BMI of the subjects did not correspond to the biochemical parameters measured. Consequently, the results showed that the nutritional deterioration of these patients was mainly reflected in their biochemical parameters rather than in their anthropometric measurements. PMID:26426172

  12. Physiology, phylogeny, early evolution, and GAPDH.

    PubMed

    Martin, William F; Cerff, Rüdiger

    2017-03-06

    The chloroplast and cytosol of plant cells harbor a number of parallel biochemical reactions germane to the Calvin cycle and glycolysis, respectively. These reactions are catalyzed by nuclear encoded, compartment-specific isoenzymes that differ in their physiochemical properties. The chloroplast cytosol isoenzymes of D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) harbor evidence of major events in the history of life: the origin of the first genes, the bacterial-archaeal split, the origin of eukaryotes, the evolution of protein compartmentation during eukaryote evolution, the origin of plastids, and the secondary endosymbiosis among the algae with complex plastids. The reaction mechanism of GAPDH entails phosphorolysis of a thioester to yield an energy-rich acyl phosphate bond, a chemistry that points to primitive pathways of energy conservation that existed even before the origin of the first free-living cells. Here, we recount the main insights that chloroplast and cytosolic GAPDH provided into endosymbiosis and physiological evolution.

  13. The START III bargaining space

    SciTech Connect

    Karas, T.H.

    1998-08-01

    The declining state of the Russian military and precarious Russian economic condition will give the US considerable advantages at the START III bargaining table. Taking the US-RF asymmetries into account, this paper discusses a menu of START III measures the US could ask for, and measures it could offer in return, in attempting to negotiate an equitable treaty. Measures the US might seek in a START III treaty include: further reductions in deployed strategic nuclear warheads, irreversibility of reductions through warhead dismantlement; beginning to bring theater nuclear weapons under mutual control, and increased transparency into the Russian nuclear weapons complex. The US may, however, wish to apply its bargaining advantages to attempting to achieve the first steps toward two long-range goals that would enhance US security: bringing theater nuclear weapons into the US-RF arms control arena, and increasing transparency into the Russian nuclear weapons complex. In exchange for measures relating to these objectives, the US might consider offering to Russia: Further strategic weapons reductions approaching levels at which the Russians believe they could maintain a degree of parity with the US; Measures to decrease the large disparities in potential deliver-system uploading capabilities that appear likely under current START II/START III scenarios; and Financial assistance in achieving START II/START III reductions as rapidly as is technically possible.

  14. Qualitative study of Bianchi type-I, III and Kantowski-Sachs cosmological models with scalar field

    NASA Astrophysics Data System (ADS)

    Chaubey, Raghavendra; Raushan, Rakesh

    2016-08-01

    A qualitative analysis of Bianchi type-I, III and Kantowski-Sachs (KS) cosmological models with a scalar field and matter fluid is performed. The analysis of the resulting equations is made by the dynamical system method. To analyze the evolution equations, we have introduced suitable transformation of variables. The evolution of the corresponding solutions is represented by curves in the phase-plane diagram. We analyze the evolution of the effective equation of state parameter for Bianchi type-I, III and KS cosmological models. The nature of critical points are analyzed and stable attractors are examined for each cosmological model.

  15. Thermal and optical properties of Tb(III), Eu(III) and Tb(III)/Eu(III) co-complexed silicone fluorinated acrylate copolymer

    NASA Astrophysics Data System (ADS)

    Zhai, Yinfeng; Xie, Hongde; Cai, Haijun; Cai, Peiqing; Seo, Hyo Jin

    2015-07-01

    Tb(III), Eu(III) and Tb(III)/Eu(III) activated silicone fluorinated acrylate (SFA) have been successfully synthesized using the method of semi-continuous emulsion polymerization. The copolymers are characterized by flourier transform infrared (FT-IR), thermal gravity analysis (TGA), photoluminescence excitation (PLE) and emission (PL) spectroscopy. The copolymer containing Tb(III) and Eu(III) ions display green and red luminescent colors under UV light excitation, respectively. The TGA curves show the thermal decomposition temperatures of the copolymers are up to about 300 °C. The PL spectra show a strong green emission at 546 nm (5D4 → 7F5) of Tb(III) complexed copolymers, and show a prominent red emission at 615 nm (5D0 → 7F2) of Eu(III) complexed copolymers. Different concentrations of Eu(III) and Tb(III) ions are introduced into the copolymer and the energy transfer from Tb(III) to Eu(III) ions in the copolymer was found. Thus, based on the results it can be suggested that SFA:Eu(III), SFA:Tb(III) and SFA:Tb(III)/Eu(III) can be used potentially as luminescent materials.

  16. The growing need for biochemical bioherbicides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The volume of herbicide use outpaces that of other pesticides. Evolution of resistance to the currently used herbicides has greatly increased the need for new modes of action (MOAs). More than 20 years have passed since the last new herbicide MOA was introduced. Natural products offer a source of...

  17. Gd(III)-Gd(III) distance measurements with chirp pump pulses.

    PubMed

    Doll, Andrin; Qi, Mian; Wili, Nino; Pribitzer, Stephan; Godt, Adelheid; Jeschke, Gunnar

    2015-10-01

    The broad EPR spectrum of Gd(III) spin labels restricts the dipolar modulation depth in distance measurements between Gd(III) pairs to a few percent. To overcome this limitation, frequency-swept chirp pulses are utilized as pump pulses in the DEER experiment. Using a model system with 3.4 nm Gd-Gd distance, application of one single chirp pump pulse at Q-band frequencies leads to modulation depths beyond 10%. However, the larger modulation depth is counteracted by a reduction of the absolute echo intensity due to the pump pulse. As supported by spin dynamics simulations, this effect is primarily driven by signal loss to double-quantum coherence and specific to the Gd(III) high spin state of S=7/2. In order to balance modulation depth and echo intensity for optimum sensitivity, a simple experimental procedure is proposed. An additional improvement by 25% in DEER sensitivity is achieved with two consecutive chirp pump pulses. These pulses pump the Gd(III) spectrum symmetrically around the observation position, therefore mutually compensating for dynamical Bloch-Siegert phase shifts at the observer spins. The improved sensitivity of the DEER data with modulation depths on the order of 20% is due to mitigation of the echo reduction effects by the consecutive pump pulses. In particular, the second pump pulse does not lead to additional signal loss if perfect inversion is assumed. Moreover, the compensation of the dynamical Bloch-Siegert phase prevents signal loss due to spatial dependence of the dynamical phase, which is caused by inhomogeneities in the driving field. The new methodology is combined with pre-polarization techniques to measure long distances up to 8.6 nm, where signal intensity and modulation depth become attenuated by long dipolar evolution windows. In addition, the influence of the zero-field splitting parameters on the echo intensity is studied with simulations. Herein, larger sensitivity is anticipated for Gd(III) complexes with zero-field splitting

  18. Gd(III)-Gd(III) distance measurements with chirp pump pulses

    NASA Astrophysics Data System (ADS)

    Doll, Andrin; Qi, Mian; Wili, Nino; Pribitzer, Stephan; Godt, Adelheid; Jeschke, Gunnar

    2015-10-01

    The broad EPR spectrum of Gd(III) spin labels restricts the dipolar modulation depth in distance measurements between Gd(III) pairs to a few percent. To overcome this limitation, frequency-swept chirp pulses are utilized as pump pulses in the DEER experiment. Using a model system with 3.4 nm Gd-Gd distance, application of one single chirp pump pulse at Q-band frequencies leads to modulation depths beyond 10%. However, the larger modulation depth is counteracted by a reduction of the absolute echo intensity due to the pump pulse. As supported by spin dynamics simulations, this effect is primarily driven by signal loss to double-quantum coherence and specific to the Gd(III) high spin state of S = 7/2. In order to balance modulation depth and echo intensity for optimum sensitivity, a simple experimental procedure is proposed. An additional improvement by 25% in DEER sensitivity is achieved with two consecutive chirp pump pulses. These pulses pump the Gd(III) spectrum symmetrically around the observation position, therefore mutually compensating for dynamical Bloch-Siegert phase shifts at the observer spins. The improved sensitivity of the DEER data with modulation depths on the order of 20% is due to mitigation of the echo reduction effects by the consecutive pump pulses. In particular, the second pump pulse does not lead to additional signal loss if perfect inversion is assumed. Moreover, the compensation of the dynamical Bloch-Siegert phase prevents signal loss due to spatial dependence of the dynamical phase, which is caused by inhomogeneities in the driving field. The new methodology is combined with pre-polarization techniques to measure long distances up to 8.6 nm, where signal intensity and modulation depth become attenuated by long dipolar evolution windows. In addition, the influence of the zero-field splitting parameters on the echo intensity is studied with simulations. Herein, larger sensitivity is anticipated for Gd(III) complexes with zero

  19. III-Nitride nanowire optoelectronics

    NASA Astrophysics Data System (ADS)

    Zhao, Songrui; Nguyen, Hieu P. T.; Kibria, Md. G.; Mi, Zetian

    2015-11-01

    Group-III nitride nanowire structures, including GaN, InN, AlN and their alloys, have been intensively studied in the past decade. Unique to this material system is that its energy bandgap can be tuned from the deep ultraviolet (~6.2 eV for AlN) to the near infrared (~0.65 eV for InN). In this article, we provide an overview on the recent progress made in III-nitride nanowire optoelectronic devices, including light emitting diodes, lasers, photodetectors, single photon sources, intraband devices, solar cells, and artificial photosynthesis. The present challenges and future prospects of III-nitride nanowire optoelectronic devices are also discussed.

  20. First Stars III Conference Summary

    NASA Astrophysics Data System (ADS)

    O'Shea, B. W.; McKee, C. F.; Heger, A.; Abel, T.

    2008-03-01

    The understanding of the formation, life, and death of Population III stars, as well as the impact that these objects had on later generations of structure formation, is one of the foremost issues in modern cosmological research and has been an active area of research during the past several years. We summarize the results presented at "First Stars III," a conference sponsored by Los Alamos National Laboratory, the Kavli Institute for Particle Astrophysics and Cosmology, and the Joint Institute for Nuclear Astrophysics. This conference, the third in a series, took place in July 2007 at the La Fonda Hotel in Santa Fe, New Mexico, U.S.A.

  1. Determination of four biochemically distinct, sequential stages during vacuole inheritance in vitro

    PubMed Central

    1994-01-01

    Vacuole inheritance in Saccharomyces cerevisiae can be reconstituted in vitro using isolated organelles, cytosol, and ATP. Using the requirements of the reaction and its susceptibility to inhibitors, we have divided the in vitro reaction into four biochemically distinct, sequential subreactions. Stage I requires exposure of vacuoles to solutions of moderate ionic strength. Stage II requires "stage I" vacuoles and cytosol. In stage III, stage II vacuoles react with ATP. Finally, during stage IV, stage III vacuoles at a certain, minimal concentration complete the fusion reaction without further requirement for any soluble components. Reagents that inhibit the overall vacuole inheritance reaction block distinct stages. Stage III of the reaction is sensitive to the proton ionophore CCCP, to inhibitors of the vacuolar ATPase such as bafilomycin A1, and to the ATP-hydrolyzing enzyme apyrase, suggesting that an electrochemical potential across the vacuolar membrane is required during this stage. Inhibition studies with the amphiphilic peptide mastoparan and GTP gamma S suggest that GTP-hydrolyzing proteins might also be involved during this stage. Microcystin-LR, a specific inhibitor of protein phosphatases of type 1 and 2A, inhibits stage IV of the inheritance reaction, indicating that a protein dephosphorylation event is necessary for fusion. The definition of these four stages may allow the development of specific assays for the factors which catalyze each of the consecutive steps of the in vitro reaction. PMID:8027190

  2. Methylenetetrahydrofolate reductase: biochemical characterization and medical significance.

    PubMed

    Trimmer, Elizabeth E

    2013-01-01

    Methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5,10-methylenetetrahydofolate (CH2-H4folate) to 5-methyltetrahydrofolate (CH3-H4folate). The enzyme employs a noncovalently-bound flavin adenine dinucleotide (FAD), which accepts reducing equivalents from NAD(P)H and transfers them to CH2-H4folate. The reaction provides the sole source of CH3-H4folate, which is utilized by methionine synthase in the synthesis of methionine from homocysteine. MTHFR plays a key role in folate metabolism and in the homeostasis of homocysteine; mutations in the enzyme lead to hyperhomocyst(e)inemia. A common C677T polymorphism in MTHFR has been associated with an increased risk for the development of cardiovascular disease, Alzheimer's disease, and depression in adults, and of neural tube defects in the fetus. The mutation also confers protection for certain types of cancers. This review presents the current knowledge of the enzyme, its biochemical characterization, and medical significance.

  3. Optofluidics in bio-chemical analysis

    NASA Astrophysics Data System (ADS)

    Guo, Yunbo; Fan, Xudong

    2012-01-01

    Optofluidics organically integrates microfluidics and photonics and is an emerging technology in biological and chemical analysis. In this paper, we overview the recent studies in bio-chemical sensing applications of optofluidics. Particularly, we report the research progress in our lab in developing diverse optofluidic devices using two unique configurations: thin-walled capillary based optofluidic ring resonator (OFRR) and multi-hole capillary based optofluidic platforms. The first one has been developed to be OFRR-based label-free biosensor, microfluidic laser based intra-cavity sensors, and on-column optical detectors for micro-gas chromatography (μGC), while the second one has been developed to be optofluidic Fabry-Pérot based label-free biosensor and optofluidic Surface-Enhanced Raman Spectroscopy (SERS) biosensor. All of these devices take advantage of superior fluidic handling capability and high sensitivity, and have been used in detecting various biological and chemical analytes in either liquid or vapor phase.

  4. Droplet microfluidics in (bio)chemical analysis.

    PubMed

    Basova, Evgenia Yu; Foret, Frantisek

    2015-01-07

    Droplet microfluidics may soon change the paradigm of performing chemical analyses and related instrumentation. It can improve not only the analysis scale, possibility for sensitivity improvement, and reduced consumption of chemical and biological reagents, but also the speed of performing a variety of unit operations. At present, microfluidic platforms can reproducibly generate monodisperse droplet populations at kHz or higher rates with droplet sizes suitable for high-throughput experiments, single-cell detection or even single molecule analysis. In addition to being used as microreactors with volume in the micro- to femtoliter range, droplet based systems have also been used to directly synthesize particles and encapsulate biological entities for biomedicine and biotechnology applications. This minireview summarizes various droplet microfluidics operations and applications for (bio)chemical assays described in the literature during the past few years.

  5. Highly valuable microalgae: biochemical and topological aspects.

    PubMed

    Pignolet, Olivier; Jubeau, Sébastien; Vaca-Garcia, Carlos; Michaud, Philippe

    2013-08-01

    The past decade has seen a surge in the interest in microalgae culture for biodiesel production and other applications as renewable biofuels as an alternative to petroleum transport fuels. The development of new technologies for the culture of these photosynthetic microorganisms and improved knowledge of their biochemical composition has spurred innovation in the field of high-value biomolecules. These developments are only economically viable if all the microalgae fractions are valorized in a biorefinery strategy. Achieving this objective requires an understanding of microalgae content and the cellular localization of the main biomolecular families in order to develop efficient harvest and sequential recovery technologies. This review summarizes the state of the art in microalgae compositions and topologies using some examples of the main industrially farmed microalgae.

  6. Thin membrane sensor with biochemical switch

    NASA Technical Reports Server (NTRS)

    Case, George D. (Inventor); Worley, III, Jennings F. (Inventor)

    1994-01-01

    A modular biosensor system for chemical or biological agent detection utilizes electrochemical measurement of an ion current across a gate membrane triggered by the reaction of the target agent with a recognition protein conjugated to a channel blocker. The sensor system includes a bioresponse simulator or biochemical switch module which contains the recognition protein-channel blocker conjugate, and in which the detection reactions occur, and a transducer module which contains a gate membrane and a measuring electrode, and in which the presence of agent is sensed electrically. In the poised state, ion channels in the gate membrane are blocked by the recognition protein-channel blocker conjugate. Detection reactions remove the recognition protein-channel blocker conjugate from the ion channels, thus eliciting an ion current surge in the gate membrane which subsequently triggers an output alarm. Sufficiently large currents are generated that simple direct current electronics are adequate for the measurements. The biosensor has applications for environmental, medical, and industrial use.

  7. The biochemical basis of hereditary fructose intolerance.

    PubMed

    Bouteldja, Nadia; Timson, David J

    2010-04-01

    Hereditary fructose intolerance is a rare, but potentially lethal, inherited disorder of fructose metabolism, caused by mutation of the aldolase B gene. Treatment currently relies solely on dietary restriction of problematic sugars. Biochemical study of defective aldolase B enzymes is key to revealing the molecular basis of the disease and providing a stronger basis for improved treatment and diagnosis. Such studies have revealed changes in enzyme activity, stability and oligomerisation. However, linking these changes to disease phenotypes has not always been straightforward. This review gives a general overview of the features of hereditary fructose intolerance, then concentrates on the biochemistry of the AP variant (Ala149Pro variant of aldolase B) and molecular pathological consequences of mutation of the aldolase B gene.

  8. Case A Binary Evolution

    SciTech Connect

    Nelson, C A; Eggleton, P P

    2001-03-28

    We undertake a comparison of observed Algol-type binaries with a library of computed Case A binary evolution tracks. The library consists of 5500 binary tracks with various values of initial primary mass M{sub 10}, mass ratio q{sub 0}, and period P{sub 0}, designed to sample the phase-space of Case A binaries in the range -0.10 {le} log M{sub 10} {le} 1.7. Each binary is evolved using a standard code with the assumption that both total mass and orbital angular momentum are conserved. This code follows the evolution of both stars until the point where contact or reverse mass transfer occurs. The resulting binary tracks show a rich variety of behavior which we sort into several subclasses of Case A and Case B. We present the results of this classification, the final mass ratio and the fraction of time spent in Roche Lobe overflow for each binary system. The conservative assumption under which we created this library is expected to hold for a broad range of binaries, where both components have spectra in the range G0 to B1 and luminosity class III - V. We gather a list of relatively well-determined observed hot Algol-type binaries meeting this criterion, as well as a list of cooler Algol-type binaries where we expect significant dynamo-driven mass loss and angular momentum loss. We fit each observed binary to our library of tracks using a {chi}{sup 2}-minimizing procedure. We find that the hot Algols display overall acceptable {chi}{sup 2}, confirming the conservative assumption, while the cool Algols show much less acceptable {chi}{sup 2} suggesting the need for more free parameters, such as mass and angular momentum loss.

  9. Psychological and Biochemical Effects of a Stress Management Program,

    DTIC Science & Technology

    risk factors for cardiovascular disease . We wanted to sample emotional, behavioral, physical and biochemical measures which might be sensitive to the changes of an effective stress management program.

  10. Biochemically enhanced methane production from coal

    NASA Astrophysics Data System (ADS)

    Opara, Aleksandra

    For many years, biogas was connected mostly with the organic matter decomposition in shallow sediments (e.g., wetlands, landfill gas, etc.). Recently, it has been realized that biogenic methane production is ongoing in many hydrocarbon reservoirs. This research examined microbial methane and carbon dioxide generation from coal. As original contributions methane production from various coal materials was examined in classical and electro-biochemical bench-scale reactors using unique, developed facultative microbial consortia that generate methane under anaerobic conditions. Facultative methanogenic populations are important as all known methanogens are strict anaerobes and their application outside laboratory would be problematic. Additional testing examined the influence of environmental conditions, such as pH, salinity, and nutrient amendments on methane and carbon dioxide generation. In 44-day ex-situ bench-scale batch bioreactor tests, up to 300,000 and 250,000 ppm methane was generated from bituminous coal and bituminous coal waste respectively, a significant improvement over 20-40 ppm methane generated from control samples. Chemical degradation of complex hydrocarbons using environmentally benign reagents, prior to microbial biodegradation and methanogenesis, resulted in dissolution of up to 5% bituminous coal and bituminous coal waste and up to 25% lignite in samples tested. Research results confirm that coal waste may be a significant underutilized resource that could be converted to useful fuel. Rapid acidification of lignite samples resulted in low pH (below 4.0), regardless of chemical pretreatment applied, and did not generate significant methane amounts. These results confirmed the importance of monitoring and adjusting in situ and ex situ environmental conditions during methane production. A patented Electro-Biochemical Reactor technology was used to supply electrons and electron acceptor environments, but appeared to influence methane generation in a

  11. Pattern Selection by Dynamical Biochemical Signals

    PubMed Central

    Palau-Ortin, David; Formosa-Jordan, Pau; Sancho, José M.; Ibañes, Marta

    2015-01-01

    The development of multicellular organisms involves cells to decide their fate upon the action of biochemical signals. This decision is often spatiotemporally coordinated such that a spatial pattern arises. The dynamics that drive pattern formation usually involve genetic nonlinear interactions and positive feedback loops. These complex dynamics may enable multiple stable patterns for the same conditions. Under these circumstances, pattern formation in a developing tissue involves a selection process: why is a certain pattern formed and not another stable one? Herein we computationally address this issue in the context of the Notch signaling pathway. We characterize a dynamical mechanism for developmental selection of a specific pattern through spatiotemporal changes of the control parameters of the dynamics, in contrast to commonly studied situations in which initial conditions and noise determine which pattern is selected among multiple stable ones. This mechanism can be understood as a path along the parameter space driven by a sequence of biochemical signals. We characterize the selection process for three different scenarios of this dynamical mechanism that can take place during development: the signal either 1) acts in all the cells at the same time, 2) acts only within a cluster of cells, or 3) propagates along the tissue. We found that key elements for pattern selection are the destabilization of the initial pattern, the subsequent exploration of other patterns determined by the spatiotemporal symmetry of the parameter changes, and the speeds of the path compared to the timescales of the pattern formation process itself. Each scenario enables the selection of different types of patterns and creates these elements in distinct ways, resulting in different features. Our approach extends the concept of selection involved in cellular decision-making, usually applied to cell-autonomous decisions, to systems that collectively make decisions through cell

  12. Biochemical processes of oligotrophic peat deposits of Vasyugan Mire

    NASA Astrophysics Data System (ADS)

    Inisheva, L. I.; Sergeeva, M. A.

    2009-04-01

    The problem of peat and mire ecosystems functioning and their rational use is the main problem of biosphere study. This problem also refers to forecasting of biosphere changes results which are global and anthropogenic. According to many scientists' research the portion of mires in earth carbon balance is about 15% of world's stock. The aim of this study is to investigate biochemical processes in oligotrophic deposits in North-eastern part of Vasyugan Mire. The investigations were made on the territory of scientific-research ground (56˚ 03´ and 56˚ 57´ NL, 82˚ 22´ and 82˚ 42´ EL). It is situated between two rivers Bakchar and Iksa (in outskirts of the village Polynyanka, Bakchar region, Tomsk oblast). Evolution of investigated mire massif began with the domination of eutrophic phytocenosis - Filicinae, then sedge. Later transfer into oligotrophic phase was accompanied by formation of meter high-moor peat deposit. The age of three-meter peat deposit reaches four thousand years. Biochemical processes of carbon cycle cover the whole peat deposit, but the process activity and its direction in different layers are defined by genesis and duration of peat formation. So, the number of cellulose-fermenting aerobes in researched peat deposits ranges from 16.8 to 75.5 million CFU/g, and anaerobic bacteria from 9.6 to 48.6 million CFU/g. The high number of aerobes is characteristic for high water levels, organizing by raised bog peats. Their number decreases along the profile in 1.7 - 2 times. The number of microflora in peat deposit is defined by the position in the landscape profile (different geneses), by the depth, by hydrothermic conditions of years and individual months. But microflora activity shows along all depth of peat deposit. We found the same in the process of studying of micromycete complex structure. There was revealed either active component micromycete complex - mycelium, or inert one - spores in a meter layer of peat deposit. If mushrooms

  13. Interplanetary density models as inferred from solar Type III bursts

    NASA Astrophysics Data System (ADS)

    Oppeneiger, Lucas; Boudjada, Mohammed Y.; Lammer, Helmut; Lichtenegger, Herbert

    2016-04-01

    We report on the density models derived from spectral features of solar Type III bursts. They are generated by beams of electrons travelling outward from the Sun along open magnetic field lines. Electrons generate Langmuir waves at the plasma frequency along their ray paths through the corona and the interplanetary medium. A large frequency band is covered by the Type III bursts from several MHz down to few kHz. In this analysis, we consider the previous empirical density models proposed to describe the electron density in the interplanetary medium. We show that those models are mainly based on the analysis of Type III bursts generated in the interplanetary medium and observed by satellites (e.g. RAE, HELIOS, VOYAGER, ULYSSES,WIND). Those models are confronted to stereoscopic observations of Type III bursts recorded by WIND, ULYSSES and CASSINI spacecraft. We discuss the spatial evolution of the electron beam along the interplanetary medium where the trajectory is an Archimedean spiral. We show that the electron beams and the source locations are depending on the choose of the empirical density models.

  14. ULK3 regulates cytokinetic abscission by phosphorylating ESCRT-III proteins.

    PubMed

    Caballe, Anna; Wenzel, Dawn M; Agromayor, Monica; Alam, Steven L; Skalicky, Jack J; Kloc, Magdalena; Carlton, Jeremy G; Labrador, Leticia; Sundquist, Wesley I; Martin-Serrano, Juan

    2015-05-26

    The endosomal sorting complexes required for transport (ESCRT) machinery mediates the physical separation between daughter cells during cytokinetic abscission. This process is regulated by the abscission checkpoint, a genome protection mechanism that relies on Aurora B and the ESCRT-III subunit CHMP4C to delay abscission in response to chromosome missegregation. In this study, we show that Unc-51-like kinase 3 (ULK3) phosphorylates and binds ESCRT-III subunits via tandem MIT domains, and thereby, delays abscission in response to lagging chromosomes, nuclear pore defects, and tension forces at the midbody. Our structural and biochemical studies reveal an unusually tight interaction between ULK3 and IST1, an ESCRT-III subunit required for abscission. We also demonstrate that IST1 phosphorylation by ULK3 is an essential signal required to sustain the abscission checkpoint and that ULK3 and CHMP4C are functionally linked components of the timer that controls abscission in multiple physiological situations.

  15. Generalized anxiety disorder: some biochemical aspects.

    PubMed

    Munjack, D J; Baltazar, P L; DeQuattro, V; Sobin, P; Palmer, R; Zulueta, A; Crocker, B; Usigli, R; Buckwalter, G; Leonard, M

    1990-04-01

    Fifty-one patients who met DSM-III criteria for generalized anxiety disorder, and who were recruited to participate in a drug outcome study, filled out a variety of rating scales and had blood samples drawn for plasma norepinephrine, epinephrine, and free 3-methoxy-4-hydroxyphenylglycol (MHPG) after a 20-min rest period. This group was compared to 15 normal controls who also had their blood drawn after a 20-min rest period. While the two groups were initially found to have significantly different levels of plasma free MHPG through the use of t tests, this finding was not confirmed by subsequent discriminant analysis.

  16. Diverse functions and reactions of class III peroxidases.

    PubMed

    Shigeto, Jun; Tsutsumi, Yuji

    2016-03-01

    Higher plants contain plant-specific peroxidases (class III peroxidase; Prxs) that exist as large multigene families. Reverse genetic studies to characterize the function of each Prx have revealed that Prxs are involved in lignification, cell elongation, stress defense and seed germination. However, the underlying mechanisms associated with plant phenotypes following genetic engineering of Prx genes are not fully understood. This is because Prxs can function as catalytic enzymes that oxidize phenolic compounds while consuming hydrogen peroxide and/or as generators of reactive oxygen species. Moreover, biochemical efforts to characterize Prxs responsible for lignin polymerization have revealed specialized activities of Prxs. In conclusion, not only spatiotemporal regulation of gene expression and protein distribution, but also differentiated oxidation properties of each Prx define the function of this class of peroxidases.

  17. Type III Secretion: Building and Operating a Remarkable Nanomachine.

    PubMed

    Portaliou, Athina G; Tsolis, Konstantinos C; Loos, Maria S; Zorzini, Valentina; Economou, Anastassios

    2016-02-01

    The Type III secretion system (T3SS) is a protein export pathway that is widespread in Gram-negative bacteria and delivers effector proteins directly into eukaryotic cells. At its core lie the injectisome (a sophisticated transmembrane secretion apparatus) and a complex network of specialized chaperones that target secretory proteins to the antechamber of the injectisome. The assembly of the system, and the subsequent secretion of proteins through it, undergo fine-tuned, hierarchical regulation. Here, we present the current understanding of the injectisome assembly process, secretion hierarchy, and the role of chaperones. We discuss these events in light of available structural and biochemical dissection and propose future directions essential to revealing mechanistic insight into this fascinating nanomachine.

  18. Organometallic neptunium(III) complexes.

    PubMed

    Dutkiewicz, Michał S; Farnaby, Joy H; Apostolidis, Christos; Colineau, Eric; Walter, Olaf; Magnani, Nicola; Gardiner, Michael G; Love, Jason B; Kaltsoyannis, Nikolas; Caciuffo, Roberto; Arnold, Polly L

    2016-08-01

    Studies of transuranic organometallic complexes provide a particularly valuable insight into covalent contributions to the metal-ligand bonding, in which the subtle differences between the transuranium actinide ions and their lighter lanthanide counterparts are of fundamental importance for the effective remediation of nuclear waste. Unlike the organometallic chemistry of uranium, which has focused strongly on U(III) and has seen some spectacular advances, that of the transuranics is significantly technically more challenging and has remained dormant. In the case of neptunium, it is limited mainly to Np(IV). Here we report the synthesis of three new Np(III) organometallic compounds and the characterization of their molecular and electronic structures. These studies suggest that Np(III) complexes could act as single-molecule magnets, and that the lower oxidation state of Np(II) is chemically accessible. In comparison with lanthanide analogues, significant d- and f-electron contributions to key Np(III) orbitals are observed, which shows that fundamental neptunium organometallic chemistry can provide new insights into the behaviour of f-elements.

  19. Title III hazardous air pollutants

    SciTech Connect

    Todd, R.

    1995-12-31

    The author presents an overview of the key provisions of Title III of the Clean Air Act Amendments of 1990. The key provisions include the following: 112(b) -- 189 Hazardous Air Pollutants (HAP); 112(a) -- Major Source: 10 TPY/25 TPY; 112(d) -- Application of MACT; 112(g) -- Modifications; 112(I) -- State Program; 112(j) -- The Hammer; and 112(r) -- Accidental Release Provisions.

  20. Biochemical subtypes of oligodendrocyte in the anterior medullary velum of the rat as revealed by the monoclonal antibody Rip.

    PubMed

    Butt, A M; Ibrahim, M; Ruge, F M; Berry, M

    1995-07-01

    Oligodendrocytes were studied in the anterior medullary velum (AMV) of the rat using the monoclonal antibody Rip, an oligodendrocyte marker of unknown function. Confocal microscopic imaging of double immunofluorescent labelling with antibodies to Rip and carbonic anhydrase II (CAII) revealed two biochemically and morphologically distinct populations of oligodendrocyte which were either Rip+CAII+ or Rip+CAII-. Double immunofluorescent labelling with Rip and myelin basic protein (MBP) or glial fibrillary acidic protein (GFAP) provided direct evidence that Rip-labelled cells were phenotypically oligodendrocytes and confirmed that Rip did not recognise astrocytes. Oligodendrocytes which were Rip+CAII+ supported numerous myelin sheaths for small diameter axons, whilst Rip+CAII- oligodendrocytes supported fewer myelin sheaths for large diameter axons. Morphologically, Rip+CAII+ oligodendrocytes corresponded to types I or II of classical nomenclature, whilst Rip+CAII- oligodendrocytes corresponded to types III and IV. The results demonstrated a biochemical difference between oligodendrocytes which myelinated small and large diameter fibres.

  1. Fifty years of co-evolution and beyond: integrating co-evolution from molecules to species.

    PubMed

    Carmona, Diego; Fitzpatrick, Connor R; Johnson, Marc T J

    2015-11-01

    Fifty years after Ehrlich and Raven's seminal paper, the idea of co-evolution continues to grow as a key concept in our understanding of organic evolution. This concept has not only provided a compelling synthesis between evolutionary biology and community ecology, but has also inspired research that extends beyond its original scope. In this article, we identify unresolved questions about the co-evolutionary process and advocate for the integration of co-evolutionary research from molecular to interspecific interactions. We address two basic questions: (i) What is co-evolution and how common is it? (ii) What is the unit of co-evolution? Both questions aim to explore the heart of the co-evolutionary process. Despite the claim that co-evolution is ubiquitous, we argue that there is in fact little evidence to support the view that reciprocal natural selection and coadaptation are common in nature. We also challenge the traditional view that co-evolution only occurs between traits of interacting species. Co-evolution has the potential to explain evolutionary processes and patterns that result from intra- and intermolecular biochemical interactions within cells, intergenomic interactions (e.g. nuclear-cytoplasmic) within species, as well as intergenomic interactions mediated by phenotypic traits between species. Research that bridges across these levels of organization will help to advance our understanding of the importance of the co-evolutionary processes in shaping the diversity of life on Earth.

  2. Origins and Evolution of Life

    NASA Astrophysics Data System (ADS)

    Gargaud, Muriel; López-García, Purificación; Martin, Hervé

    2011-01-01

    Part I. What Is Life?: 1. Problems raised by a definition of life M. Morange; 2. Some remarks about uses of cosmological anthropic 'principles' D. Lambert; 3. Minimal cell: the biologist point of view C. Brochier-Armanet; 4. Minimal cell: the computer scientist point of view H. Bersini; 5. Origins of life: computing and simulation approaches B. Billoud; Part II. Astronomical and Geophysical Context of the Emergence of Life: 6. Organic molecules in interstellar medium C. Ceccarelli and C. Cernicharo; 7. Cosmochemical evolution and the origin of life: insights from meteorites S. Pizzarello; 8. Astronomical constraints on the emergence of life M. Gounelle and T. Montmerle; 9. Formation of habitable planets J. Chambers; 10. The concept of galactic habitable zone N. Prantzos; 11. The young Sun and its influence on planetary atmospheres M. Güdel and J. Kasting; 12. Climates of the Earth G. Ramstein; Part III. Role of Water in the Emergence of Life: 13. Liquid water: a necessary condition to all forms of life K. Bartik, G. Bruylants, E. Locci and J. Reisse; 14. The role of water in the formation and evolution of planets T. Encrenaz; 15. Water on Mars J. P. Bibring; Part IV. From Non-Living Systems to Life: 16. Energetic constraints on prebiotic pathways: application to the emergence of translation R. Pascal and L. Boiteau; 17. Comparative genomics and early cell evolution A. Lazcano; 18. Origin and evolution of metabolisms J. Peretó; Part V. Mechanisms for Life Evolution: 19. Molecular phylogeny: inferring the patterns of evolution E. Douzery; 20. Horizontal gene transfer: mechanisms and evolutionary consequences D. Moreira; 21. The role of symbiosis in eukaryotic evolution A. Latorre, A. Durbán, A. Moya and J. Peretó; Part VI. Life in Extreme Conditions: 22. Life in extreme conditions: Deinococcus radiodurans, an organism able to survive prolonged desiccation and high doses of ionising radiation S. Sommer and M. Toueille; 23. Molecular effects of UV and ionizing

  3. Biochemical adaptations of notothenioid fishes: comparisons between cold temperate South American and New Zealand species and Antarctic species.

    PubMed

    Petricorena, Zulema L Coppes; Somero, George N

    2007-07-01

    Fishes of the perciform suborder Notothenioidei afford an excellent opportunity for studying the evolution and functional importance of diverse types of biochemical adaptation to temperature. Antarctic notothenioids have evolved numerous biochemical adaptations to stably cold waters, including antifreeze glycoproteins, which inhibit growth of ice crystals, and enzymatic proteins with cold-adapted specific activities (k(cat) values) and substrate binding abilities (K(m) values), which support metabolism at low temperatures. Antarctic notothenioids also exhibit the loss of certain biochemical traits that are ubiquitous in other fishes, including the heat-shock response (HSR) and, in members of the family Channichthyidae, hemoglobins and myoglobins. Tolerance of warm temperatures is also truncated in stenothermal Antarctic notothenioids. In contrast to Antarctic notothenioids, notothenioid species found in South American and New Zealand waters have biochemistries more reflective of cold-temperate environments. Some of the contemporary non-Antarctic notothenioids likely derive from ancestral species that evolved in the Antarctic and later "escaped" to lower latitude waters when the Antarctic Polar Front temporarily shifted northward during the late Miocene. Studies of cold-temperate notothenioids may enable the timing of critical events in the evolution of Antarctic notothenioids to be determined, notably the chronology of acquisition and amplification of antifreeze glycoprotein genes and the loss of the HSR. Genomic studies may reveal how the gene regulatory networks involved in acclimation to temperature differ between stenotherms like the Antarctic notothenioids and more eurythermal species like cold-temperate notothenioids. Comparative studies of Antarctic and cold-temperate notothenioids thus have high promise for revealing the mechanisms by which temperature-adaptive biochemical traits are acquired - or through which traits that cease to be of advantage under

  4. Molecular evolution of SRP cycle components: functional implications.

    PubMed

    Althoff, S; Selinger, D; Wise, J A

    1994-06-11

    Signal recognition particle (SRP) is a cytoplasmic ribonucleoprotein that targets a subset of nascent presecretory proteins to the endoplasmic reticulum membrane. We have considered the SRP cycle from the perspective of molecular evolution, using recently determined sequences of genes or cDNAs encoding homologs of SRP (7SL) RNA, the Srp54 protein (Srp54p), and the alpha subunit of the SRP receptor (SR alpha) from a broad spectrum of organisms, together with the remaining five polypeptides of mammalian SRP. Our analysis provides insight into the significance of structural variation in SRP RNA and identifies novel conserved motifs in protein components of this pathway. The lack of congruence between an established phylogenetic tree and size variation in 7SL homologs implies the occurrence of several independent events that eliminated more than half the sequence content of this RNA during bacterial evolution. The apparently non-essential structures are domain I, a tRNA-like element that is constant in archaea, varies in size among eucaryotes, and is generally missing in bacteria, and domain III, a tightly base-paired hairpin that is present in all eucaryotic and archeal SRP RNAs but is invariably absent in bacteria. Based on both structural and functional considerations, we propose that the conserved core of SRP consists minimally of the 54 kDa signal sequence-binding protein complexed with the loosely base-paired domain IV helix of SRP RNA, and is also likely to contain a homolog of the Srp68 protein. Comparative sequence analysis of the methionine-rich M domains from a diverse array of Srp54p homologs reveals an extended region of amino acid identity that resembles a recently identified RNA recognition motif. Multiple sequence alignment of the G domains of Srp54p and SR alpha homologs indicates that these two polypeptides exhibit significant similarity even outside the four GTPase consensus motifs, including a block of nine contiguous amino acids in a location

  5. Gamma-Ray Bursts and Population III Stars

    NASA Astrophysics Data System (ADS)

    Toma, Kenji; Yoon, Sung-Chul; Bromm, Volker

    2016-12-01

    Gamma-ray bursts (GRBs) are ideal probes of the epoch of the first stars and galaxies. We review the recent theoretical understanding of the formation and evolution of the first (so-called Population III) stars, in light of their viability of providing GRB progenitors. We proceed to discuss possible unique observational signatures of such bursts, based on the current formation scenario of long GRBs. These include signatures related to the prompt emission mechanism, as well as to the afterglow radiation, where the surrounding intergalactic medium might imprint a telltale absorption spectrum. We emphasize important remaining uncertainties in our emerging theoretical framework.

  6. Numerical simulations of type-III solar radio bursts.

    PubMed

    Li, B; Robinson, P A; Cairns, I H

    2006-04-14

    The first numerical simulations are presented for type-III solar radio bursts in the inhomogeneous solar corona and interplanetary space, that include microscale quasilinear and nonlinear processes, intermediate-scale driven ambient density fluctuations, and large scale evolution of electron beams, Langmuir and ion sound waves, and fundamental and harmonic electromagnetic emission. Bidirectional coronal emission is asymmetric between the upward and downward directions, and harmonic emission dominates fundamental emission. In interplanetary space, fundamental and/or harmonic emission can be important. Langmuir and ion sound waves are bursty and the statistics of Langmuir wave energy agree well with the predictions of stochastic growth theory.

  7. Biochemical and physiological processes associated with the differential ozone response in ozone-tolerant and sensitive soybean genotypes.

    PubMed

    Chutteang, C; Booker, F L; Na-Ngern, P; Burton, A; Aoki, M; Burkey, K O

    2016-01-01

    Biochemical and physiological traits of two soybean [Glycine max (L.) Merr.] genotypes differing in sensitivity to ozone (O3 ) were investigated to determine the possible basis for the differential response. Fiskeby III (O3 -tolerant) and Mandarin (Ottawa) (O3 -sensitive) were grown in a greenhouse with charcoal-filtered air for 4 weeks, then treated with O3 for 7 h·day(-1) in greenhouse chambers. Mandarin (Ottawa) showed significantly more leaf injury and hydrogen peroxide (H2 O2 ) and superoxide (O2 (-) ) production compared with Fiskeby III. Peroxidase activity in Mandarin (Ottawa) was 31% higher with O3 but was not significantly different in Fiskeby III. Ozone did not affect superoxide dismutase or glutathione reductase activities, or leaf concentrations of glutathione or ascorbic acid. Thus, variation in O3 response between Fiskeby III and Mandarin (Ottawa) was not explained by differences in antioxidant enzymes and metabolites tested. Ethylene emission from leaves declined in Fiskeby III following O3 exposure but not in Mandarin (Ottawa). Ozone exposure reduced quantum yield (ΦPSII ), electron transport rate (ETR) and photochemical quenching (qp ) in Mandarin (Ottawa) more than in Fiskeby III, indicating that efficiency of energy conversion of PSII and photosynthetic electron transport was altered differently in the two genotypes. Short-term exposure to O3 had minimal effects on net carbon exchange rates of both soybean cultivars. A trend toward higher stomatal conductance in Mandarin (Ottawa) suggested stomatal exclusion might contribute to differential O3 sensitivity of the two genotypes. Increased sensitivity of Mandarin (Ottawa) to O3 was associated with higher H2 O2 and O2 (-) production compared with Fiskeby III, possibly associated with genotype differences in stomatal function or regulation of ethylene during the initial phases of O3 response.

  8. A Biochemical Approach to the Problem of Dyslexia.

    ERIC Educational Resources Information Center

    Baker, Sidney McDonald

    1985-01-01

    The paper presents the case of a sixth-grade boy, labeled dyslexic, who responded positively to a biochemical approach. Remedy of iron, zinc, and Vitamin B-6 deficiencies as well as an imbalance of fatty acids resulted in improvements in hair and skin and also in reading. A biochemical approach to behavior problems is proposed. (Author/CL)

  9. Editorial: ESBES - European Society of Biochemical Engineering Sciences.

    PubMed

    Ferreira, Guilherme; Jungbauer, Alois

    2013-06-01

    The latest ESBES special issue on "Biochemical Engineering Sciences" is edited by Prof. Guilherme Ferreira (Chairman, ESBES) and Prof. Alois Jungbauer (co-Editor-in-Chief, Biotechnology Journal). This special issue comprises the latest research in biochemical engineering science presented at the 9(th) ESBES Conference held in Istanbul, Turkey in 2012.

  10. Model-Based Design of Biochemical Microreactors

    PubMed Central

    Elbinger, Tobias; Gahn, Markus; Neuss-Radu, Maria; Hante, Falk M.; Voll, Lars M.; Leugering, Günter; Knabner, Peter

    2016-01-01

    Mathematical modeling of biochemical pathways is an important resource in Synthetic Biology, as the predictive power of simulating synthetic pathways represents an important step in the design of synthetic metabolons. In this paper, we are concerned with the mathematical modeling, simulation, and optimization of metabolic processes in biochemical microreactors able to carry out enzymatic reactions and to exchange metabolites with their surrounding medium. The results of the reported modeling approach are incorporated in the design of the first microreactor prototypes that are under construction. These microreactors consist of compartments separated by membranes carrying specific transporters for the input of substrates and export of products. Inside the compartments of the reactor multienzyme complexes assembled on nano-beads by peptide adapters are used to carry out metabolic reactions. The spatially resolved mathematical model describing the ongoing processes consists of a system of diffusion equations together with boundary and initial conditions. The boundary conditions model the exchange of metabolites with the neighboring compartments and the reactions at the surface of the nano-beads carrying the multienzyme complexes. Efficient and accurate approaches for numerical simulation of the mathematical model and for optimal design of the microreactor are developed. As a proof-of-concept scenario, a synthetic pathway for the conversion of sucrose to glucose-6-phosphate (G6P) was chosen. In this context, the mathematical model is employed to compute the spatio-temporal distributions of the metabolite concentrations, as well as application relevant quantities like the outflow rate of G6P. These computations are performed for different scenarios, where the number of beads as well as their loading capacity are varied. The computed metabolite distributions show spatial patterns, which differ for different experimental arrangements. Furthermore, the total output of G6P

  11. Model-Based Design of Biochemical Microreactors.

    PubMed

    Elbinger, Tobias; Gahn, Markus; Neuss-Radu, Maria; Hante, Falk M; Voll, Lars M; Leugering, Günter; Knabner, Peter

    2016-01-01

    Mathematical modeling of biochemical pathways is an important resource in Synthetic Biology, as the predictive power of simulating synthetic pathways represents an important step in the design of synthetic metabolons. In this paper, we are concerned with the mathematical modeling, simulation, and optimization of metabolic processes in biochemical microreactors able to carry out enzymatic reactions and to exchange metabolites with their surrounding medium. The results of the reported modeling approach are incorporated in the design of the first microreactor prototypes that are under construction. These microreactors consist of compartments separated by membranes carrying specific transporters for the input of substrates and export of products. Inside the compartments of the reactor multienzyme complexes assembled on nano-beads by peptide adapters are used to carry out metabolic reactions. The spatially resolved mathematical model describing the ongoing processes consists of a system of diffusion equations together with boundary and initial conditions. The boundary conditions model the exchange of metabolites with the neighboring compartments and the reactions at the surface of the nano-beads carrying the multienzyme complexes. Efficient and accurate approaches for numerical simulation of the mathematical model and for optimal design of the microreactor are developed. As a proof-of-concept scenario, a synthetic pathway for the conversion of sucrose to glucose-6-phosphate (G6P) was chosen. In this context, the mathematical model is employed to compute the spatio-temporal distributions of the metabolite concentrations, as well as application relevant quantities like the outflow rate of G6P. These computations are performed for different scenarios, where the number of beads as well as their loading capacity are varied. The computed metabolite distributions show spatial patterns, which differ for different experimental arrangements. Furthermore, the total output of G6P

  12. Progress in III-V materials technology

    NASA Astrophysics Data System (ADS)

    Grant, Ian R.

    2004-12-01

    Compound semiconductors, in the form of GaAs and InP have achieved major commercial significance in areas of application such as mobile communications, displays and telecoms and offer a versatility of function beyond the capabilities of Si. III-V compounds, and in particular GaAs, have since their early development been the subject of defence related interest. Support from this sector established the basic materials technologies and nurtured development up until their commercial breakthrough into consumer products. GaAs, for example, now provides essential components for mobile phones and CD / DVD players. An overview is presented of the crystal growth and processing methods used in the manufacture of these materials. Current state of the art characteristics on crystal form and quality are discussed, together with the evolution of single crystal growth techniques. Consideration is given to how these principal compounds together with the minor materials, InSb, GaSb and InAs are employed in diverse applications over a broad spectral range, together with information on markets and future perspectives.

  13. Insect evolution.

    PubMed

    Engel, Michael S

    2015-10-05

    It goes without saying that insects epitomize diversity, and with over a million documented species they stand out as one of the most remarkable lineages in the 3.5-billion-year history of life on earth (Figure 1). This reality is passé to even the layperson and is taken for granted in the same way none of us think much of our breathing as we go about our day, and yet insects are just as vital to our existence. Insects are simultaneously familiar and foreign to us, and while a small fraction are beloved or reviled, most are simply ignored. These inexorable evolutionary overachievers outnumber us all, their segmented body plan is remarkably labile, they combine a capacity for high rates of speciation with low levels of natural extinction, and their history of successes eclipses those of the more familiar ages of dinosaurs and mammals alike. It is their evolution - persisting over vast expanses of geological time and inextricably implicated in the diversification of other lineages - that stands as one of the most expansive subjects in biology.

  14. Chemical constraints on the contribution of population III stars to cosmic reionization

    SciTech Connect

    Kulkarni, Girish; Hennawi, Joseph F.; Rollinde, Emmanuel; Vangioni, Elisabeth

    2014-05-20

    Recent studies have highlighted that galaxies at z = 6-8 fall short of producing enough ionizing photons to reionize the intergalactic medium, and suggest that Population III stars could resolve this tension, because their harder spectra can produce ∼10 × more ionizing photons than Population II. We use a semi-analytic model of galaxy formation, which tracks galactic chemical evolution, to gauge the impact of Population III stars on reionization. Population III supernovae produce distinct metal abundances, and we argue that the duration of the Population III era can be constrained by precise relative abundance measurements in high-z damped Lyα absorbers (DLAs), which provide a chemical record of past star formation. We find that a single generation of Population III stars can self-enrich galaxies above the critical metallicity Z {sub crit} = 10{sup –4} Z {sub ☉} for the Population III-to-II transition, on a very short timescale t {sub self-enrich} ∼ 10{sup 6} yr, owing to the large metal yields and short lifetimes of Population III stars. This subsequently terminates the Population III era, so they contribute ≳ 50% of the ionizing photons only for z ≳ 30, and at z = 10 contribute <1%. The Population III contribution can be increased by delaying metal mixing into the interstellar medium. However, comparing the resulting metal abundance pattern to existing measurements in z ≲ 6 DLAs, we show that the observed [O/Si] ratios of absorbers rule out Population III stars being a major contributor to reionization. Future abundance measurements of z ∼ 7-8 QSOs and gamma-ray bursts should probe the era when the chemical vestiges of Population III star formation become detectable.

  15. Chemical Constraints on the Contribution of Population III Stars to Cosmic Reionization

    NASA Astrophysics Data System (ADS)

    Kulkarni, Girish; Hennawi, Joseph F.; Rollinde, Emmanuel; Vangioni, Elisabeth

    2014-05-01

    Recent studies have highlighted that galaxies at z = 6-8 fall short of producing enough ionizing photons to reionize the intergalactic medium, and suggest that Population III stars could resolve this tension, because their harder spectra can produce ~10 × more ionizing photons than Population II. We use a semi-analytic model of galaxy formation, which tracks galactic chemical evolution, to gauge the impact of Population III stars on reionization. Population III supernovae produce distinct metal abundances, and we argue that the duration of the Population III era can be constrained by precise relative abundance measurements in high-z damped Lyα absorbers (DLAs), which provide a chemical record of past star formation. We find that a single generation of Population III stars can self-enrich galaxies above the critical metallicity Z crit = 10-4 Z ⊙ for the Population III-to-II transition, on a very short timescale t self-enrich ~ 106 yr, owing to the large metal yields and short lifetimes of Population III stars. This subsequently terminates the Population III era, so they contribute >~ 50% of the ionizing photons only for z >~ 30, and at z = 10 contribute <1%. The Population III contribution can be increased by delaying metal mixing into the interstellar medium. However, comparing the resulting metal abundance pattern to existing measurements in z <~ 6 DLAs, we show that the observed [O/Si] ratios of absorbers rule out Population III stars being a major contributor to reionization. Future abundance measurements of z ~ 7-8 QSOs and gamma-ray bursts should probe the era when the chemical vestiges of Population III star formation become detectable.

  16. Efficient inefficiency: biochemical "junk" may represent molecular bridesmaids awaiting emergent function as a buffer against environmental fluctuation.

    PubMed

    Yun, Anthony J; Lee, Patrick Y; Doux, John D

    2006-01-01

    The biochemical function of many parts of the genome, transcriptome, proteome, and interactome remain largely unknown. We propose that portions of these fundamental building blocks of life have no current biochemical function per se. Rather, sections of these "omes" may contribute to an inventory of biochemical parts and circuits that participate in the development of emergent functions. Low fidelity deoxyribonucleic acid replication, transcription, translation, and post-translational modification all represent potential mechanisms to produce an inventory of parts. Stochastic processes that influence the conformations of ribonucleic acid molecules and proteins may also contribute to potential biochemical inventory. Some components of the biochemical inventory may enable future adaptations, some may produce disease, and some may remain useless. The function of many of these components await discovery, not by science, but by evolution. While carrying such purposeless biochemical units may appear to dilute fitness by exacting a thermodynamic cost, we argue that net fitness becomes enhanced when considering the value for potential future innovations. One can envision components that intermingle, interact, and act out mock pathways, but in most cases remain molecular bridesmaids. Given sufficiently low thermodynamic cost, such stochastic cycling may persist until a markedly advantageous or cataclysmically disadvantageous trait emerges. Maladaptive screening and utilization of inventory content can lead to disease phenotypes, a process buffered and regulated in part by the heat shock protein and stress response network. Whereas failure of the ubiquitin pathway to recycle misfolded proteins has become increasingly recognized as a source of disease, protein misfolding may itself represent one step in a process that maximizes functional innovation through increasing proteomic diversity. Fractal correlates of these processes occur at the organizational level of cells and

  17. Study of interfacial phenomena for bio/chemical sensing applications

    NASA Astrophysics Data System (ADS)

    Min, Hwall

    This work presents the fundamental study of biological and chemical interfacial phenomena and (bio)chemical sensing applications using high frequency resonator arrays. To realize a versatile (bio)chemical sensing system for the fundamental study as well as their practical applications, the following three distinct components were studied and developed: i) detection platforms with high sensitivity, ii) novel innovative sensing materials with high selectivity, iii) analytical model for data interpretation. 8-pixel micromachined quartz crystal resonator (muQCR) arrays with a fundamental resonance frequency of 60 ¡V 90 MHz have been used to provide a reliable detection platform with high sensitivity. Room temperature ionic liquid (RTIL) has been explored and integrated into the sensing system as a smart chemical sensing material. The use of nanoporous gold (np-Au) enables the combination of the resonator and surface-enhanced Raman spectroscopy for both quantitative and qualitative measurement. A statistical model for the characterization of resonator behavior to study the protein adsorption kinetics is developed by random sequential adsorption (RSA) approach with the integration of an effective surface depletion theory. The investigation of the adsorption kinetics of blood proteins is reported as the fundamental study of biological phenomena using the proposed sensing system. The aim of this work is to study different aspects of protein adsorption and kinetics of adsorption process with blood proteins on different surfaces. We specifically focus on surface depletion effect in conjunction with the RSA model to explain the observed adsorption isotherm characteristics. A number of case studies on protein adsorption conducted using the proposed sensing system has been discussed. Effort is specifically made to understand adsorption kinetics, and the effect of surface on the adsorption process as well as the properties of the adsorbed protein layer. The second half of the

  18. [Biochemical tests for identifying Pasteurella multocida].

    PubMed

    Karaivanov, L

    1984-01-01

    Studied was the biochemical activity of a total of 168 strains of Pasteurella--73 isolated from birds (48 from cases of acute fowl cholera, and 25--of chronic cholera), and 95 isolated from mammals (3 from lambs, 24 from pigs, 36 from cattle, and 32 from rabbits) with regard to the tests determining the hemolytic activity, production of indol, reduction of nitrates, breakdown of urea, beta galactosidase activity, production of hydrogen sulfide, ornitin-, arginine-, lysine-decarboxylase-, and phosphatase activity, and the fermentation of substrates such as manite, glucose, galactose, saccharose, manose, levulose, dulcite, lactose, maltose, rafinose, trechalose, salicin, melobiose, icelobiose, arabinose, xylose, and sorbite. To differentiate Pasteurella multocida strains isolated from mamals from those isolated from birds the phosphatase activity test on solid media with sodium phenolphtalein diphosphate had to be employed Pasteurella organisms isolated from mammals showed positive phosphatase activity, while those isolated from birds exhibited a negative one. Arabinose and xylose fermentation tests could simultaneously be used. Pasteurellae isolated in cases of acute fowl cholera showed positive reaction for arabinose and a negative one for xylose, while the strains isolated from mammals showed the reverse activity. The strains isolated in cases of chronic fowl cholera were shown to belong to this group.

  19. Biochemical indicators of hepatotoxic effects of pesticides.

    PubMed

    Dahamna, S; Sekfali, N; Walker, C H

    2004-01-01

    Pesticides can cause damage to man and beneficial organisms. Some sub-lethal effects of pesticides were studied in birds with a view to identifying characteristic biochemical responses that may be useful for the monitoring of exposure to sub-lethal levels in the field. Pesticides were used: demeton-S-methyl, (DSM), chlorpyriphos, chlorfenviphos, triazophos, pirimicarb, methiocarb and permethrin. Blood was collected before dosing, and 2, 6, 24, 48 and 72 hours after the treatment from the brachial vein of birds. Enzyme activities were assayed in the plasma or serum samples obtained. The assays used were GOT, MDH, GDH, SDH, GAMMA GT and ChE. The results showed an increase in plasma and serum GOT and gamma-GT levels were found in all animals treated with the previous pesticides. The level of ChE increased in birds after treatment with permethrin. It was concluded that the pesticides cause structural and functional changes in the liver and also, the measurement of the previous parameter activities may be useful for assessing exposure and sub-lethal effects of pesticides on the wildlife.

  20. Reaction networks and kinetics of biochemical systems.

    PubMed

    Arceo, Carlene Perpetua P; Jose, Editha C; Lao, Angelyn R; Mendoza, Eduardo R

    2017-01-01

    This paper further develops the connection between Chemical Reaction Network Theory (CRNT) and Biochemical Systems Theory (BST) that we recently introduced [1]. We first use algebraic properties of kinetic sets to study the set of complex factorizable kinetics CFK(N) on a CRN, which shares many characteristics with its subset of mass action kinetics. In particular, we extend the Theorem of Feinberg-Horn [9] on the coincidence of the kinetic and stoichiometric subsets of a mass action system to CF kinetics, using the concept of span surjectivity. We also introduce the branching type of a network, which determines the availability of kinetics on it and allows us to characterize the networks for which all kinetics are complex factorizable: A "Kinetics Landscape" provides an overview of kinetics sets, their algebraic properties and containment relationships. We then apply our results and those (of other CRNT researchers) reviewed in [1] to fifteen BST models of complex biological systems and discover novel network and kinetic properties that so far have not been widely studied in CRNT. In our view, these findings show an important benefit of connecting CRNT and BST modeling efforts.

  1. Biochemical studies of the tracheobronchial epithelium

    SciTech Connect

    Mass, M.J.; Kaufman, D.G.

    1984-06-01

    Tracheobronchial epithelium has been a focus of intense investigation in the field of chemical carcinogenesis. We have reviewed some biochemical investigations that have evolved through linkage with carcinogenesis research. These areas of investigation have included kinetics of carcinogen metabolism, identification of carcinogen metabolites, levels of carcinogen binding to DNA, and analysis of carcinogen-DNA adducts. Such studies appear to have provided a reasonable explanation for the susceptibilities of the respiratory tracts of rats and hamsters to carcinogenesis by benzo(a)pyrene. Coinciding with the attempts to understand the initiation of carcinogenesis in the respiratory tract has also been a major thrust aimed at effecting its prevention both in humans and in animal models for human bronchogenic carcinoma. These studies have concerned the effects of derivatives of vitamin A (retinoids) and their influence on normal cell biology and biochemistry of this tissue. Recent investigations have included the effects of retinoid deficiency on the synthesis of RNA and the identification of RNA species associated with this biological state, and also have included the effects of retinoids on the synthesis of mucus-related glycoproteins. Tracheal organ cultures from retinoid-deficient hamsters have been used successfully to indicate the potency of synthetic retinoids by monitoring the reversal of squamous metaplasia. Techniques applied to this tissue have also served to elucidate features of the metabolism of retinoic acid using high pressure liquid chromatography. 94 references, 9 figures, 2 tables.

  2. [Cystinuria update: clinical, biochemical and genetic aspects].

    PubMed

    Orts Costa, J A; Zúñiga Cabrera, A; Martínez de la Cára y Salmerón, J

    2003-06-01

    Cystinuria is an autosomal recessive disorder with an estimated incidence of 1 case in 7000 live births, that results in elevated urinary excretion of cystine and dibasic aminoacids: ornithine, lysine and arginine. Discussed by Sir Archibald Edward Garrod, in 1908, as one of the four first known inborn errors of metabolism, it is characterized by a defect in transport of cystine and dibasic aminoacids, that affects their reabsortion in both renal tubule and gastrointestinal tract. To date, according to the recent molecular findings, two genes have been identified as responsible for this disease: SLC3A1 and SLC7A9. A more accurate pheno/genotyping identification of cystinuric patients will allow to improve prophilaxis and therapy for this illness. Cystinuria only causes recurrent urolithiasis (about 1-2 / of renal calculi in adults) and its associated complications as clinical feature because of poor cystine solubility at low pH. An accurate control over prohylaxis (based on high water intake and potassium citrate treatment, on first line, and tiol-derivatives treatment, on second line) must be taken in patients -like homozygous type I- with high lithiasis risk. However, approximately one half of patients under prophylaxis control will develop recurrent lithiasis; in this case, only urology or surgical approaches would be possible. 474 Updated knowledge about biochemical, genetic, clinical, diagnosis, prevention, treatment and prognosis aspects of this, relatively unusual, disease has been reviewed in this article.

  3. Applied spectrophotometry: analysis of a biochemical mixture.

    PubMed

    Trumbo, Toni A; Schultz, Emeric; Borland, Michael G; Pugh, Michael Eugene

    2013-01-01

    Spectrophotometric analysis is essential for determining biomolecule concentration of a solution and is employed ubiquitously in biochemistry and molecular biology. The application of the Beer-Lambert-Bouguer Lawis routinely used to determine the concentration of DNA, RNA or protein. There is however a significant difference in determining the concentration of a given species (RNA, DNA, protein) in isolation (a contrived circumstance) as opposed to determining that concentration in the presence of other species (a more realistic situation). To present the student with a more realistic laboratory experience and also to fill a hole that we believe exists in student experience prior to reaching a biochemistry course, we have devised a three week laboratory experience designed so that students learn to: connect laboratory practice with theory, apply the Beer-Lambert-Bougert Law to biochemical analyses, demonstrate the utility and limitations of example quantitative colorimetric assays, demonstrate the utility and limitations of UV analyses for biomolecules, develop strategies for analysis of a solution of unknown biomolecular composition, use digital micropipettors to make accurate and precise measurements, and apply graphing software.

  4. Multiple capillary biochemical analyzer with barrier member

    DOEpatents

    Dovichi, Norman J.; Zhang, Jian Z.

    1996-01-01

    A multiple capillary biochemical analyzer for sequencing DNA and performing other analyses, in which a set of capillaries extends from wells in a microtiter plate into a cuvette. In the cuvette the capillaries are held on fixed closely spaced centers by passing through a sandwich construction having a pair of metal shims which squeeze between them a rubber gasket, forming a leak proof seal for an interior chamber in which the capillary ends are positioned. Sheath fluid enters the chamber and entrains filament sample streams from the capillaries. The filament sample streams, and sheath fluid, flow through aligned holes in a barrier member spaced close to the capillary ends, into a collection chamber having a lower glass window. The filament streams are illuminated above the barrier member by a laser, causing them to fluoresce. The fluorescence is viewed end-on by a CCD camera chip located below the glass window. The arrangement ensures an equal optical path length from all fluorescing spots to the CCD chip and also blocks scattered fluorescence illumination, providing more uniform results and an improved signal to noise ratio.

  5. Multiple capillary biochemical analyzer with barrier member

    DOEpatents

    Dovichi, N.J.; Zhang, J.Z.

    1996-10-22

    A multiple capillary biochemical analyzer is disclosed for sequencing DNA and performing other analyses, in which a set of capillaries extends from wells in a microtiter plate into a cuvette. In the cuvette the capillaries are held on fixed closely spaced centers by passing through a sandwich construction having a pair of metal shims which squeeze between them a rubber gasket, forming a leak proof seal for an interior chamber in which the capillary ends are positioned. Sheath fluid enters the chamber and entrains filament sample streams from the capillaries. The filament sample streams, and sheath fluid, flow through aligned holes in a barrier member spaced close to the capillary ends, into a collection chamber having a lower glass window. The filament streams are illuminated above the barrier member by a laser, causing them to fluoresce. The fluorescence is viewed end-on by a CCD camera chip located below the glass window. The arrangement ensures an equal optical path length from all fluorescing spots to the CCD chip and also blocks scattered fluorescence illumination, providing more uniform results and an improved signal-to-noise ratio. 12 figs.

  6. Robustness analysis of stochastic biochemical systems.

    PubMed

    Ceska, Milan; Safránek, David; Dražan, Sven; Brim, Luboš

    2014-01-01

    We propose a new framework for rigorous robustness analysis of stochastic biochemical systems that is based on probabilistic model checking techniques. We adapt the general definition of robustness introduced by Kitano to the class of stochastic systems modelled as continuous time Markov Chains in order to extensively analyse and compare robustness of biological models with uncertain parameters. The framework utilises novel computational methods that enable to effectively evaluate the robustness of models with respect to quantitative temporal properties and parameters such as reaction rate constants and initial conditions. We have applied the framework to gene regulation as an example of a central biological mechanism where intrinsic and extrinsic stochasticity plays crucial role due to low numbers of DNA and RNA molecules. Using our methods we have obtained a comprehensive and precise analysis of stochastic dynamics under parameter uncertainty. Furthermore, we apply our framework to compare several variants of two-component signalling networks from the perspective of robustness with respect to intrinsic noise caused by low populations of signalling components. We have successfully extended previous studies performed on deterministic models (ODE) and showed that stochasticity may significantly affect obtained predictions. Our case studies demonstrate that the framework can provide deeper insight into the role of key parameters in maintaining the system functionality and thus it significantly contributes to formal methods in computational systems biology.

  7. A biochemically structured model for Saccharomyces cerevisiae.

    PubMed

    Lei, F; Rotbøll, M; Jørgensen, S B

    2001-07-12

    A biochemically structured model for the aerobic growth of Saccharomyces cerevisiae on glucose and ethanol is presented. The model focuses on the pyruvate and acetaldehyde branch points where overflow metabolism occurs when the growth changes from oxidative to oxido-reductive. The model is designed to describe the onset of aerobic alcoholic fermentation during steady-state as well as under dynamical conditions, by triggering an increase in the glycolytic flux using a key signalling component which is assumed to be closely related to acetaldehyde. An investigation of the modelled process dynamics in a continuous cultivation revealed multiple steady states in a region of dilution rates around the transition between oxidative and oxido-reductive growth. A bifurcation analysis using the two external variables, the dilution rate, D, and the inlet concentration of glucose, S(f), as parameters, showed that a fold bifurcation occurs close to the critical dilution rate resulting in multiple steady-states. The region of dilution rates within which multiple steady states may occur depends strongly on the substrate feed concentration. Consequently a single steady state may prevail at low feed concentrations, whereas multiple steady states may occur over a relatively wide range of dilution rates at higher feed concentrations.

  8. Jovian type III radio bursts

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.; Gurnett, D. A.; Scarf, F. L.

    1989-01-01

    Radio bursts have been observed in the Voyager plasma wave data from Jupiter that bear a striking resemblance to solar type III radio bursts. The emissions lie in the frequency range near 10 kHz, have durations of a minute or so, and occur in a set of periodically spaced bursts. The spacing between primary bursts is typically 15 min, but the bursts may have additional components which recur on time scales of about 3 min. The similarity with solar type III radio bursts suggests a source mechanism involving the movement of energetic electrons through a density gradient in the plasma surrounding Jupiter. The periodicity of bursts suggests Io may be involved in the generation of waves, since the timing is similar to the Alfven wave travel time from one hemisphere to the other through the Io torus.

  9. Transition probabilities in O III

    NASA Astrophysics Data System (ADS)

    Froese Fischer, Charlotte

    1994-01-01

    Transition data has been computed in the MCHF + Breit-Pauli approximation for a number of the low lying triplets in O III. Special attention was given to the 2p3p 3P-2p3d 3P transition which is a primary cascade for the Bowen fluorescence mechanism in O III. The relativistic, largely spin-orbit, effect on the intensity ratio of primary decays was found to be as large as 50%, whereas the effect on secondary cascades was less than 30%. Agreement with astrophysically observed intensity ratios is excellent. There also is good agreement between the present liftimes and the beam-foil mean lifetimes obtained by Pinnington et al., though for 2p3p 3D and 3S the theoretical lifetimes are considerably shorter.

  10. NIF Title III engineering plan

    SciTech Connect

    Deis, G

    1998-06-01

    The purpose of this document is to define the work that must be accomplished by the NIF Project during Title III Engineering. This definition is intended to be sufficiently detailed to provide a framework for yearly planning, to clearly identify the specific deliverables so that the Project teams can focus on them, and to provide a common set of objectives and processes across the Project. This plan has been preceded by similar documents for Title I and Title II design and complements the Site Management Plan, the Project Control Manual, the Quality Assurance Program Plan, the RM Parsons NIF Title III Configuration Control Plan, the Integrated Project Schedule, the Preliminary Safety Analysis Report, the Configuration Management Plan, and the Transition Plan.

  11. Biochemical evaluations in skeletal muscles of primates with MPTP Parkinson-like syndrome.

    PubMed

    Pastoris, O; Dossena, M; Foppa, P; Catapano, M; Ferrari, R; Dagani, F

    1995-06-01

    The toxic effects of the neurotoxin MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) in primates can be exploited for investigating the physiopathology of Parkinson's disease which may also cause functional alterations of skeletal muscles, whose biochemical modifications have been studied very little. Some enzyme activities related to energy transduction in skeletal muscles were evaluated (gastrocnemius, soleus and biceps) from MPTP-treated monkeys. Systemically administered MPTP altered the enzyme activities related to: (i) the anaerobic glycolytic pathway (decrease in hexokinase and phosphofructokinase activities; increase in lactate dehydrogenase activity); (ii) the tricarboxylic acid cycle (decrease in malate dehydrogenase activity); (iii) the electron transfer chain (decrease in cytochrome oxidase activity related to complex IV). No alteration in mitochondrial Complex I was observed. Treatment with an ergot alkaloid derivative (dihydroergocryptine) modified some alterations in the muscle enzyme activities and reduced the rigidity and some autonomic dysfunction.

  12. Temperature-sensitive mutants of frog virus 3: biochemical and genetic characterization.

    PubMed Central

    Chinchar, V G; Granoff, A

    1986-01-01

    Nineteen frog virus 3 temperature-sensitive mutants were isolated after mutagenesis with nitrosoguanidine and assayed for viral DNA, RNA, and protein synthesis, as well as assembly site formation at permissive (25 degrees C) and nonpermissive (30 degrees C) temperatures. In addition, mutants were characterized for complementation by both quantitative and qualitative assays. Based on the genetic and biochemical data, the 19 mutants, along with 9 mutants isolated earlier, were ordered into four phenotypic classes which define defects in virion morphogenesis (class I), late mRNA synthesis (class II), viral assembly site formation (class III), and viral DNA synthesis (class IV). In addition, we used two-factor crosses to order 11 mutants, comprising 7 complementation groups, onto a linkage map spanning 77 recombination units. Images PMID:3951023

  13. Silver europium(III) polyphosphate

    PubMed Central

    Ayadi, Mounir; Férid, Mokhtar; Moine, Bernard

    2009-01-01

    Europium(III) silver polyphosphate, AgEu(PO3)4, was prepared by the flux method. The atomic arrangement is built up by infinite (PO3)n chains (periodicity of 4) extending along the c axis. These chains are joined to each other by EuO8 dodeca­hedra. The Ag+ cations are located in the voids of this arrangement and are surrounded by five oxygen atoms in a distorted [4+1] coordination. PMID:21582031

  14. The evolution of peptide hormones.

    PubMed

    Niall, H D

    1982-01-01

    Despite limitations in our present knowledge it is already possible to discern the main features of peptide hormone evolution, since the same mechanisms (and indeed the same hormone molecules) function in many different ways. This underlying unity of organization has its basis in the tendency of biochemical networks, once established, to survive and diversify. The most surprising recent findings in endocrinology have been the discovery of vertebrate peptide hormones in multiple sites within the same organism, and the reports, persuasive but requiring confirmation, of vertebrate hormones in primitive unicellular organisms (20, 20a). Perhaps the major challenge for the future is to define the roles and interactions of the many peptide hormones identified in brain (18). The most primitive bacteria and the human brain, though an enormous evolutionary distance apart, may have more in common than we have recognized until now. As Axelrod & Hamilton have pointed out in a recent provocative article, "The Evolution of Cooperation" (1), bacteria, though lacking a brain, are capable of adaptive behavior that can be analysed in terms of game theory. It is clear that we can learn a great deal about the whole evolutionary process from a study of the versatile and durable peptide hormones molecules.

  15. Organometallic neptunium(III) complexes

    NASA Astrophysics Data System (ADS)

    Dutkiewicz, Michał S.; Farnaby, Joy H.; Apostolidis, Christos; Colineau, Eric; Walter, Olaf; Magnani, Nicola; Gardiner, Michael G.; Love, Jason B.; Kaltsoyannis, Nikolas; Caciuffo, Roberto; Arnold, Polly L.

    2016-08-01

    Studies of transuranic organometallic complexes provide a particularly valuable insight into covalent contributions to the metal-ligand bonding, in which the subtle differences between the transuranium actinide ions and their lighter lanthanide counterparts are of fundamental importance for the effective remediation of nuclear waste. Unlike the organometallic chemistry of uranium, which has focused strongly on UIII and has seen some spectacular advances, that of the transuranics is significantly technically more challenging and has remained dormant. In the case of neptunium, it is limited mainly to NpIV. Here we report the synthesis of three new NpIII organometallic compounds and the characterization of their molecular and electronic structures. These studies suggest that NpIII complexes could act as single-molecule magnets, and that the lower oxidation state of NpII is chemically accessible. In comparison with lanthanide analogues, significant d- and f-electron contributions to key NpIII orbitals are observed, which shows that fundamental neptunium organometallic chemistry can provide new insights into the behaviour of f-elements.

  16. A Three Generation Study with Effect of Imidacloprid in Rats: Biochemical and Histopathological Investigation

    PubMed Central

    Vohra, Prerna; Khera, Kuldeep Singh

    2015-01-01

    Objectives: This study was designed to evaluate the dose-dependent toxic effects of imidacloprid on the female ratsthat were treated through three generations (F0, F1, and F2). F2 female rats were sacrificed at the end of the experiment to see the long-term effect of imidacloprid. Materials and Methods: Rats were divided into three groups of 6 each. Group I served as control. Group II served as treated I and given 1/45th LD50 (10 mg/kg/day) of imidacloprid. Group III served as treated II and given 1/22th LD50 (20 mg/kg/day) of imidacloprid. After 60 days, oral administration of imidacloprid females were mated with normal males to get F1 and F2 generation. F2 generation female rats were sacrificed at the end of the experiment. Biochemical and a histopathological investigation was done for three groups of F2 generation and statistically analyzed by ANOVA. Results: Average feed intake of F2 female rats was significantly reduced (P < 0.01) at 20 mg/kg/day dose of imidacloprid. There was a significant increase in the activity of alanine aminotransferase, AKP, and glucose 6-phosphate dehydrogenase in Group III rats of F2 generation. There was a significant decrease in acetylcholine esterase activity in plasma and brain of both the imidacloprid treated groups. Tissue samples of liver, kidney, and brain of females of F2 generation showed histopathological condition. Conclusion: The results indicated that imidacloprid at a dose of 20 mg/kg bw/day exerts significant toxicological effects on biochemical and histological studies of F2 generation females as compare to 10 mg/kg bw/day. PMID:26862272

  17. Association of europium(III), americium(III), and curium(III) with cellulose, chitin, and chitosan.

    PubMed

    Ozaki, Takuo; Kimura, Takaumi; Ohnuki, Toshihiko; Kirishima, Akira; Yoshida, Takahiro; Isobe, Hiroshi; Francis, Arokiasamy J

    2006-08-01

    The association of trivalent f-elements-Eu(III), Am(III), and Cm(III)--with cellulose, chitin, and chitosan was determined by batch experiments and time-resolved, laser-induced fluorescence spectroscopy (TRLFS). The properties of these biopolymers as an adsorbent were characterized based on speciation calculation of Eu(III). The adsorption study showed that an increase of the ionic strength by NaCl did not affect the adsorption kinetics of Eu(III), Am(III), and Cm(III) for all the biopolymers, but the addition of Na2CO3 significantly delayed the kinetics because of their trivalent f-element complexation with carbonate ions. It also was suggested from the speciation calculation study that all the biopolymers were degraded under alkaline conditions, leading to their masking of the adsorption of Eu(III), Am(III), and Cm(III) on the nondegraded biopolymers. The masking effect was higher for cellulose than for chitin and chitosan, indicating that of the three, cellulose was degraded most significantly in alkaline solutions. Desorption experiments suggested that some portion of the adsorbed Eu(III) penetrated deep into the matrix, being isolated in a cavity-like site. The TRLFS study showed that the coordination environment of Eu(III) is stabilized mainly by the inner spherical coordination in chitin and by the outer spherical coordination in chitosan, with less association in cellulose in comparison to chitin and chitosan. These results suggest that the association of these biopolymers with Eu(III), Am(III), and Cm(III) is governed not only by the affinity of the functional groups alone but also by other factors, such as the macromolecular steric effect. The association of degraded materials of the biopolymers also should be taken into consideration for an accurate prediction of the influence of biopolymers on the migration behavior of trivalent f-elements.

  18. Tracing the evolution of avian wing digits.

    PubMed

    Xu, Xing; Mackem, Susan

    2013-06-17

    It is widely accepted that birds are a subgroup of dinosaurs, but there is an apparent conflict: modern birds have been thought to possess only the middle three fingers (digits II-III-IV) of an idealized five-digit tetrapod hand based on embryological data, but their Mesozoic tetanuran dinosaur ancestors are considered to have the first three digits (I-II-III) based on fossil evidence. How could such an evolutionary quirk arise? Various hypotheses have been proposed to resolve this paradox. Adding to the confusion, some recent developmental studies support a I-II-III designation for avian wing digits whereas some recent paleontological data are consistent with a II-III-IV identification of the Mesozoic tetanuran digits. A comprehensive analysis of both paleontological and developmental data suggests that the evolution of the avian wing digits may have been driven by homeotic transformations of digit identity, which are more likely to have occurred in a partial and piecemeal manner. Additionally, recent genetic studies in mouse models showing plausible mechanisms for central digit loss invite consideration of new alternative possibilities (I-II-IV or I-III-IV) for the homologies of avian wing digits. While much progress has been made, some advances point to the complexity of the problem and a final resolution to this ongoing debate demands additional work from both paleontological and developmental perspectives, which will surely yield new insights on mechanisms of evolutionary adaptation.

  19. Effect of Training on Physiological and Biochemical Variables of Soccer Players of Different Age Groups

    PubMed Central

    Manna, Indranil; Khanna, Gulshan Lal; Chandra Dhara, Prakash

    2010-01-01

    Purpose To find out the effect of training on selected physiological and biochemical variables of Indian soccer players of different age groups. Methods A total of 120 soccer players volunteered for the study, were divided (n = 30) into 4 groups: (i) under 16 years (U16), (ii) under 19 years (U19), (iii) under 23 years (U23), (iv) senior (SR). The training sessions were divided into 2 phases (a) Preparatory Phase (PP, 8 weeks) and (b) Competitive Phase (CP, 4 weeks). The training program consisted of aerobic, anaerobic and skill development, and were completed 4 hrs/day; 5 days/week. Selected physiological and biochemical variables were measured at zero level (baseline data, BD) and at the end of PP and CP. Results A significant increase (P < 0.05) in lean body mass (LBM), VO2max, anaerobic power, grip and back strength, urea, uric acid and high density lipoprotein cholesterol (HDL-C); and a significant decrease (P < 0.05) in body fat, hemoglobin (Hb), total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) were detected in some groups in PP and CP phases of the training when compare to BD. However, no significant change was found in body mass and maximal heart rate of the players after the training program. Conclusion This study would provide useful information for training and selection of soccer players of different age groups. PMID:22375187

  20. Hemato-biochemical and hormonal profiles in post-partum water buffaloes (Bubalus bubalis)

    PubMed Central

    Kumar, Sunil; Balhara, A. K.; Kumar, Rajesh; Kumar, Naresh; Buragohain, Lukumoni; Baro, Daoharu; Sharma, R. K.; Phulia, S. K.; Singh, Inderjeet

    2015-01-01

    Aim: The objective of the present study was to compare serum as well as follicular fluid (FF) biochemical and hormonal profiles along with hematological parameters in postpartum estrus, anestrus, and cystic buffaloes. Materials and Methods: Postpartum buffaloes were selected in three different groups (within 40-60 days of parturition at estrus-Group-I, postpartum >90 days at anestrum-Group-II, and postpartum cystic buffaloes in Group III). The animals selected were examined for follicular wave dynamics by routine trans-rectal ultrasonography and FF was collected by transvaginal ultrasound-guided ovum pick up technique. All hematological and biochemical parameters were analyzed by automatic analyzers while hormonal profiles analyzed by commercially available ELISA kits. Results: In the present investigation, estrum and anestrum animal differ significantly in hemoglobin levels. Serum estradiol differs significantly in estrus and anestrus while no significant difference in progesterone concentration was noted among all three stages. The results of our study suggest that significant higher increase in total protein (TP), calcium and glucose values in estrum while urea, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase significantly higher in anestrum animals. Conclusion: The conclusion of the present study is that TP and albumin, calcium, urea, glucose affects oocyte development and quality. PMID:27047125

  1. Biochemical and serological characterization of Bacteroides intermedius strains isolated from the deep periodontal pocket.

    PubMed Central

    Dahlén, G; Wikström, M; Renvert, S; Gmür, R; Guggenheim, B

    1990-01-01

    Fifty-one fluorescence-positive black-pigmented Bacteroides strains obtained from 51 patients with deep periodontal pockets (greater than 6 mm) were identified and characterized. Fifty of these strains were presumptively identified as Bacteroides intermedius according to the indole reaction. This was confirmed by further biochemical characterization. The 50 strains from diseased sites were then compared with 16 B. intermedius strains isolated from periodontally healthy individuals with no signs of destructive periodontal disease. Tests for antimicrobial susceptibility showed similar patterns for all 50 pocket-derived strains, except for one beta-lactamase-positive strain that was resistant to penicillin G and ampicillin. Forty-seven strains were tested for binding of three monoclonal antibodies defining three distinct serogroups of B. intermedius. Thirty-one strains belonged to serogroup I, three to serogroup II and thirteen to serogroup III. In comparison to the strains from the shallow periodontal pockets, serogroup I was significantly overrepresented in the patient group with periodontal disease. We conclude that saccharolytic black-pigmented Bacteroides species from deep periodontal pockets constituted, with very rare exceptions, a biochemically homogeneous but antigenically heterogeneous group of B. intermedius and that serogroup I is predominantly found in deep periodontal lesions. PMID:2229351

  2. 21 CFR 1308.13 - Schedule III.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Schedule III. 1308.13 Section 1308.13 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE SCHEDULES OF CONTROLLED SUBSTANCES Schedules § 1308.13 Schedule III. (a) Schedule III shall consist of the drugs and other substances,...

  3. 21 CFR 1308.13 - Schedule III.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Schedule III. 1308.13 Section 1308.13 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE SCHEDULES OF CONTROLLED SUBSTANCES Schedules § 1308.13 Schedule III. (a) Schedule III shall consist of the drugs and other substances,...

  4. [Origin and evolution of peptide-protein bioregulators].

    PubMed

    Chipens, G I; Freĭdlin, I S; Skliarova, S N

    1987-01-01

    Possible evolutionary pathways of cellular regulatory systems are discussed. Analysis of animal evolution suggests that peptide and protein bioregulators emerged at an early stage during formation of biochemical systems in prokaryotic cells involving protein synthesis on ribosomes, the processes of exo- and endocytosis and limited proteolysis reactions. Primary autocrine bioregulators are compared with growth factors. Models for cellular bioregulation are discussed in which both cell receptors and peptide/protein ligands, primarily immunoglobins, act as prehormones. Their internalization and limited proteolysis can lead to formation of low-molecular peptides (tetines) acting as autocrine or paracrine bioregulators. Basing on the concept of biochemical universality, it is suggested that the effects of many growth factors, hormones, immunoglobulins, mono- and lymphokins are mediated by identical or similar (carrying the same signatures) fragments which are produced in cells due to limited proteolysis reactions and which are directly involved in activation of biochemical systems in these cells.

  5. Pellagra and alcoholism: a biochemical perspective.

    PubMed

    Badawy, Abdulla A-B

    2014-01-01

    Historical and clinical aspects of pellagra and its relationship to alcoholism are reviewed from a biochemical perspective. Pellagra is caused by deficiency of niacin (nicotinic acid) and/or its tryptophan (Trp) precursor and is compounded by B vitamin deficiencies. Existence on maize or sorghum diets and loss of or failure to isolate niacin from them led to pellagra incidence in India, South Africa, Southern Europe in the 18th century and the USA following the civil war. Pellagra is also induced by drugs inhibiting the conversion of Trp to niacin and by conditions of gastrointestinal dysfunction. Skin photosensitivity in pellagra may be due to decreased synthesis of the Trp metabolite picolinic acid → zinc deficiency → decreased skin levels of the histidine metabolite urocanic acid and possibly also increased levels of the haem precursor 5-aminolaevulinic acid (5-ALA) and photo-reactive porphyrins. Depression in pellagra may be due to a serotonin deficiency caused by decreased Trp availability to the brain. Anxiety and other neurological disturbances may be caused by 5-ALA and the Trp metabolite kynurenic acid. Pellagra symptoms are resolved by niacin, but aggravated mainly by vitamin B6. Alcohol dependence can induce or aggravate pellagra by inducing malnutrition, gastrointestinal disturbances and B vitamin deficiencies, inhibiting the conversion of Trp to niacin and promoting the accumulation of 5-ALA and porphyrins. Alcoholic pellagra encephalopathy should be managed with niacin, other B vitamins and adequate protein nutrition. Future studies should explore the potential role of 5-ALA and also KA in the skin and neurological disturbances in pellagra.

  6. Identification, Biochemical Characterization, and Evolution of the Rhizopus oryzae 99-880 Polygalacturonase Gene Family

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A search of the recently sequenced Rhizopus oryzae strain 99-880 genome database uncovered 18 putative polygalacturonase genes with 2 genes being identical and only 1 with similarity to a previously reported R. oryzae polygalacturonase gene. The 17 different genes share 50% to greater than 90% iden...

  7. Biochemical evolution. I. Polymerization on internal, organophilic silica surfaces of dealuminated zeolites and feldspars

    PubMed Central

    Smith, Joseph V.

    1998-01-01

    Catalysis at mineral surfaces might generate replicating biopolymers from simple chemicals supplied by meteorites, volcanic gases, and photochemical gas reactions. Many ideas are implausible in detail because the proposed mineral surfaces strongly prefer water and other ionic species to organic ones. The molecular sieve silicalite (Union Carbide; = Al-free Mobil ZSM-5 zeolite) has a three-dimensional, 10-ring channel system whose electrically neutral Si-O surface strongly adsorbs organic species over water. Three -O-Si tetrahedral bonds lie in the surface, and the fourth Si-O points inwards. In contrast, the outward Si-OH of simple quartz and feldspar crystals generates their ionic organophobicity. The ZSM-5-type zeolite mutinaite occurs in Antarctica with boggsite and tschernichite (Al-analog of Mobil Beta). Archean mutinaite might have become de-aluminated toward silicalite during hot/cold/wet/dry cycles. Catalytic activity of silicalite increases linearly with Al-OH substitution for Si, and Al atoms tend to avoid each other. Adjacent organophilic and catalytic Al-OH regions in nanometer channels might have scavenged organic species for catalytic assembly into specific polymers protected from prompt photochemical destruction. Polymer migration along weathered silicic surfaces of micrometer-wide channels of feldspars might have led to assembly of replicating catalytic biomolecules and perhaps primitive cellular organisms. Silica-rich volcanic glasses should have been abundant on the early Earth, ready for crystallization into zeolites and feldspars, as in present continental basins. Abundant chert from weakly metamorphosed Archaean rocks might retain microscopic clues to the proposed mineral adsorbent/catalysts. Other framework silicas are possible, including ones with laevo/dextro one-dimensional channels. Organic molecules, transition-metal ions, and P occur inside modern feldspars. PMID:9520372

  8. SIM Configuration Evolution

    NASA Technical Reports Server (NTRS)

    Aaron, Kim M.

    2000-01-01

    The Space Interferometry Mission (SIM) is a space-based 10 m baseline Michelson interferometer. Planned for launch in 2005 aboard a Delta III launch vehicle, or equivalent, its primary objective is to measure the positions of stars and other celestial objects with an unprecedented accuracy of 4 micro arc seconds. With such an instrument, tremendous advancement can be expected in our understanding of stellar and galactic dynamics. Using triangulation from opposite sides of the orbit around the sun (i.e. by using parallax) one can measure the distance to any observable object in our galaxy. By directly measuring the orbital wobble of nearby stars, the mass and orbit of planets can be determined over a wide range of parameters. The distribution of velocity within nearby galaxies will be measurable. Observations of these and other objects will improve the calibration of distance estimators by more than an order of magnitude. This will permit a much better determination of the Hubble Constant as well as improving our overall understanding of the evolution of the universe. SIM has undergone several transformations, especially over the past year and a half since the start of Phase A. During this phase of a project, it is desirable to perform system-level trade studies, so the substantial evolution of the design that has occurred is quite appropriate. Part of the trade-off process has addressed two major underlying architectures: SIM Classic; and Son of SIM. The difference between these two architectures is related to the overall arrangement of the optical elements and the associated metrology system. Several different configurations have been developed for each architecture. Each configuration is the result of design choices that are influenced by many competing considerations. Some of the more important aspects will be discussed. The Space Interferometry Mission has some extremely challenging goals: millikelvin thermal stability, nanometer stabilization of optics

  9. Neurotypic cell attachment and growth on III-nitride lateral polarity structures.

    PubMed

    Bain, L E; Kirste, R; Johnson, C A; Ghashghaei, H T; Collazo, R; Ivanisevic, A

    2016-01-01

    III-nitride materials have recently received increasing levels of attention for their potential to successfully interface with, and sense biochemical interactions in biological systems. Expanding on available sensing schemes (including transistor-based devices,) a III-N lateral polarity structure capable of introducing quasi-phase matching through a periodic polarity grating presents a novel platform for second harmonic generation. This platform constitutes a non-linear optical phenomenon with exquisite sensitivity to the chemical state of a surface or interface. To characterize the response of a biological system to the nanostructured lateral polarity structures, we cultured neurotypic PC12 cells on AlGaN with varying ratios of Al:Ga - 0, 0.4, 0.6, and 1 - and on surfaces of varying pitch to the III-polar vs. N-polar grating - 5, 10, 20 and 50 μm. While some toxicity associated with increasing Al is observed, we documented and quantified trends in cell responses to the local material polarity and nanoscale roughness. The nitrogen-polar material has a significantly higher nanoscale roughness than III-polar regions, and a 80-200 nm step height difference between the III-polar and N-polar materials in the lateral polarity configuration generates adequate changes in topography to influence cell growth, improves cell adhesion and promotes cell migration along the direction of the features. As the designed material configuration is further explored for biochemical sensing, the lateral polarity scheme may provide a route in assessing the non-specific protein adsorption to this varying nano-topography that drives the subsequent cell response.

  10. Development of Demographic Norms for Four New WAIS-III/WMS-III Indexes

    ERIC Educational Resources Information Center

    Lange, Rael T.; Chelune, Gordon J.; Taylor, Michael J.; Woodward, Todd S.; Heaton, Robert K.

    2006-01-01

    Following the publication of the third edition Wechsler scales (i.e., WAIS-III and WMS-III), demographically corrected norms were made available in the form of a computerized scoring program (i.e., WAIS-III/WMS-III/WIAT-II Scoring Assistant). These norms correct for age, gender, ethnicity, and education. Since then, four new indexes have been…

  11. Systems biology solutions for biochemical production challenges.

    PubMed

    Hansen, Anne Sofie Lærke; Lennen, Rebecca M; Sonnenschein, Nikolaus; Herrgård, Markus J

    2017-03-16

    There is an urgent need to significantly accelerate the development of microbial cell factories to produce fuels and chemicals from renewable feedstocks in order to facilitate the transition to a biobased society. Methods commonly used within the field of systems biology including omics characterization, genome-scale metabolic modeling, and adaptive laboratory evolution can be readily deployed in metabolic engineering projects. However, high performance strains usually carry tens of genetic modifications and need to operate in challenging environmental conditions. This additional complexity compared to basic science research requires pushing systems biology strategies to their limits and often spurs innovative developments that benefit fields outside metabolic engineering. Here we survey recent advanced applications of systems biology methods in engineering microbial production strains for biofuels and -chemicals.

  12. Palladium(III) in Synthesis and Catalysis

    PubMed Central

    Powers, David C.; Ritter, Tobias

    2011-01-01

    While the organometallic chemistry of Pd in its (0), (+II), and (+IV) oxidation states is well-established, organometallic Pd(III) chemistry remains widely unexplored. Few characterized Pd(III) complexes are known, which has inhibited detailed study of the organometallic chemistry of Pd(III). In this review, the potential roles of both mono- and dinuclear Pd(III) complexes in organometallic chemistry will be discussed. While not widely recognized, Pd in the (+III) oxidation state may play a significant role in a variety of known Pd-catalyzed reactions. PMID:21461129

  13. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  14. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  15. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  16. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  17. 40 CFR 158.2080 - Experimental use permit data requirements-biochemical pesticides.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements-biochemical pesticides. 158.2080 Section 158.2080 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2080 Experimental use permit data requirements—biochemical pesticides. (a) Sections...

  18. Molecular and structural basis of ESCRT-III recruitment to membranes during archaeal cell division.

    PubMed

    Samson, Rachel Y; Obita, Takayuki; Hodgson, Ben; Shaw, Michael K; Chong, Parkson Lee-Gau; Williams, Roger L; Bell, Stephen D

    2011-01-21

    Members of the crenarchaeal kingdom, such as Sulfolobus, divide by binary fission yet lack genes for the otherwise near-ubiquitous tubulin and actin superfamilies of cytoskeletal proteins. Recent work has established that Sulfolobus homologs of the eukaryotic ESCRT-III and Vps4 components of the ESCRT machinery play an important role in Sulfolobus cell division. In eukaryotes, several pathways recruit ESCRT-III proteins to their sites of action. However, the positioning determinants for archaeal ESCRT-III are not known. Here, we identify a protein, CdvA, that is responsible for recruiting Sulfolobus ESCRT-III to membranes. Overexpression of the isolated ESCRT-III domain that interacts with CdvA results in the generation of nucleoid-free cells. Furthermore, CdvA and ESCRT-III synergize to deform archaeal membranes in vitro. The structure of the CdvA/ESCRT-III interface gives insight into the evolution of the more complex and modular eukaryotic ESCRT complex.

  19. Development of demographic norms for four new WAIS-III/WMS-III indexes.

    PubMed

    Lange, Rael T; Chelune, Gordon J; Taylor, Michael J; Woodward, Todd S; Heaton, Robert K

    2006-06-01

    Following the publication of the third edition Wechsler scales (i.e., WAIS-III and WMS-III), demographically corrected norms were made available in the form of a computerized scoring program (i.e., WAIS-III/WMS-III/WIAT-II Scoring Assistant). These norms correct for age, gender, ethnicity, and education. Since then, four new indexes have been developed: the WAIS-III General Ability Index, the WMS-III Delayed Memory Index, and the two alternate Immediate and Delayed Memory Indexes. The purpose of this study was to develop demographically corrected norms for the four new indexes using the standardization sample and education oversample from the WAIS-III and WMS-III. These norms were developed using the same methodology as the demographically corrected norms made available in the WAIS-III/WMS-III/WIAT-II Scoring Assistant.

  20. Evolution: Help for the Confused.

    ERIC Educational Resources Information Center

    Scheer, Bradley T.

    1979-01-01

    Written in response to an earlier article questioning certain aspects of evolution theory. Discusses ontogeny and phylogeny, the basis of evolution, chance or purpose in evolution, micro and macro-evolution, reversibility, and the evolution processes today. (MA)

  1. Evolution of feline immunodeficiency virus Gag proteins.

    PubMed

    Burkala, Evan; Poss, Mary

    2007-10-01

    We evaluated the predicted biochemical properties of Gag proteins from a diverse group of feline immunodeficiency viruses (FIV) to determine how different evolutionary histories of virus and host have changed or constrained these important structural proteins. Our data are based on FIV sequences derived from domestic cat (FIVfca), cougar (FIVpco), and lions (FIVple). Analyses consisted of determining the selective forces acting at each position in the protein and the comparing predictions for secondary structure, charge, hydrophobicity and flexibility for matrix, capsid and nucleocapsid, and the C-terminal peptide, which comprise the Gag proteins. We demonstrate that differences among the FIV Gag proteins have largely arisen by neutral evolution, although many neutrally evolving regions have maintained biochemical features. Regions with predicted differences in biochemical features appear to involve intramolecular interactions and structural elements that undergo conformational changes during particle maturation. In contrast, the majority of sites involved in intermolecular contacts on the protein surface are constrained by purifying selection. There is also conservation of sites that interact with host proteins associated with cellular trafficking and particle budding. NC is the only protein with evidence of positive selection, two of which occur in the N-terminal region responsible for RNA binding and interaction with host proteins.

  2. Stabilization of the Escherichia coli DNA polymerase III ε subunit by the θ subunit favors in vivo assembly of the Pol III catalytic core

    PubMed Central

    Conte, Emanuele; Vincelli, Gabriele; Schaaper, Roel M.; Bressanin, Daniela; Stefan, Alessandra; Dal Piaz, Fabrizio; Hochkoeppler, Alejandro

    2012-01-01

    Escherichia coli DNA polymerase III holoenzyme (HE) contains a core polymerase consisting of three subunits: α(polymerase), ε(3′-5′ exonuclease), and θ. Genetic experiments suggested that θ subunit stabilizes the intrinsically labile ε subunit and, furthermore, that θ might affect the cellular amounts of Pol III core and HE. Here, we provide biochemical evidence supporting this model by analyzing the amounts of the relevant proteins. First, we show that a ΔholE strain (lacking θ subunit) displays reduced amounts of free ε. We also demonstrate the existence of a dimer of ε, which may be involved in the stabilization of the protein. Second, θ, when overexpressed, dissociates the ε dimer and significantly increases the amount of Pol III core. The stability of ε also depends on cellular chaperones, including DnaK. Here, we report that: (i) temperature shift-up of ΔdnaK strains leads to rapid depletion of ε, and (ii) overproduction of θ overcomes both the depletion of ε and the temperature sensitivity of the strain. Overall, our data suggest that ε is a critical factor in the assembly of Pol III core, and that this is role is strongly influenced by the θ subunit through its prevention of ε degradation. PMID:22546509

  3. Secular Evolution of Galaxies

    NASA Astrophysics Data System (ADS)

    Falcón-Barroso, Jesús; Knapen, Johan H.

    2013-10-01

    Preface; 1. Secular evolution in disk galaxies John Kormendy; 2. Galaxy morphology Ronald J. Buta; 3. Dynamics of secular evolution James Binney; 4. Bars and secular evolution in disk galaxies: theoretical input E. Athanassoula; 5. Stellar populations Reynier F. Peletier; 6. Star formation rate indicators Daniela Calzetti; 7. The evolving interstellar medium Jacqueline van Gorkom; 8. Evolution of star formation and gas Nick Z. Scoville; 9. Cosmological evolution of galaxies Isaac Shlosman.

  4. SAGE III on ISS Lessons Learned on Thermal Interface Design

    NASA Technical Reports Server (NTRS)

    Davis, Warren

    2015-01-01

    The Stratospheric Aerosol and Gas Experiment III (SAGE III) instrument - the fifth in a series of instruments developed for monitoring vertical distribution of aerosols, ozone, and other trace gases in the Earth's stratosphere and troposphere - is currently scheduled for delivery to the International Space Station (ISS) via the SpaceX Dragon vehicle in 2016. The Instrument Adapter Module (IAM), one of many SAGE III subsystems, continuously dissipates a considerable amount of thermal energy during mission operations. Although a portion of this energy is transferred via its large radiator surface area, the majority must be conductively transferred to the ExPRESS Payload Adapter (ExPA) to satisfy thermal mitigation requirements. The baseline IAM-ExPA mechanical interface did not afford the thermal conductance necessary to prevent the IAM from overheating in hot on-orbit cases, and high interfacial conductance was difficult to achieve given the large span between mechanical fasteners, less than stringent flatness specifications, and material usage constraints due to strict contamination requirements. This paper will examine the evolution of the IAM-ExPA thermal interface over the course of three design iterations and will include discussion on design challenges, material selection, testing successes and failures, and lessons learned.

  5. Phylogenetic analysis of uroporphyrinogen III synthase (UROS) gene.

    PubMed

    Shaik, Abjal Pasha; Alsaeed, Abbas H; Sultana, Asma

    2012-01-01

    The uroporphyrinogen III synthase (UROS) enzyme (also known as hydroxymethylbilane hydrolyase) catalyzes the cyclization of hydroxymethylbilane to uroporphyrinogen III during heme biosynthesis. A deficiency of this enzyme is associated with the very rare Gunther's disease or congenital erythropoietic porphyria, an autosomal recessive inborn error of metabolism. The current study investigated the possible role of UROS (Homo sapiens [EC: 4.2.1.75; 265 aa; 1371 bp mRNA; Entrez Pubmed ref NP_000366.1, NM_000375.2]) in evolution by studying the phylogenetic relationship and divergence of this gene using computational methods. The UROS protein sequences from various taxa were retrieved from GenBank database and were compared using Clustal-W (multiple sequence alignment) with defaults and a first-pass phylogenetic tree was built using neighbor-joining method as in DELTA BLAST 2.2.27+ version. A total of 163 BLAST hits were found for the uroporphyrinogen III synthase query sequence and these hits showed putative conserved domain, HemD superfamily (as on 14(th) Nov 2012). We then narrowed down the search by manually deleting the proteins which were not UROS sequences and sequences belonging to phyla other than Chordata were deleted. A repeat phylogenetic analysis of 39 taxa was performed using PhyML and TreeDyn software to confirm that UROS is a highly conserved protein with approximately 85% conserved sequences in almost all chordate taxons emphasizing its importance in heme synthesis.

  6. The Nimbus III Michelson Interferometer.

    PubMed

    Hanel, R A; Schlachman, B; Clark, F D; Prokesh, C H; Taylor, J B; Wilson, W M; Chaney, L

    1970-08-01

    The Michelson interferometer flown on Nimbus III in April 1969 has obtained infrared emission spectra of the earth and its atmosphere within 400 cm(-1) and 2000 cm(-1) (5 micro and 25 micro). Spectra of good quality have been recorded with a spectral resolution corresponding to 5 cm(-1). This paper discusses the design of the instrument including the optical layout, the phase locked loop operation of the Michelson motor, and the functioning of the reference interferometer. The methods of data reduction and in-flight calibration are demonstrated on sample spectra recorded while in orbit around the earth.

  7. Detection and characterisation of an overmodified type III collagen by analysis of non-cutaneous connective tissues in a patient with Ehlers-Danlos syndrome IV.

    PubMed Central

    Nuytinck, L; Narcisi, P; Nicholls, A; Renard, J P; Pope, F M; De Paepe, A

    1992-01-01

    The clinical and biochemical observations in a patient with a mild form of Ehlers-Danlos syndrome (EDS) type IV are described. The patient's skin fibroblasts produced markedly diminished amounts of type III collagen. SDS-polyacrylamide gel electrophoresis of collagens produced by cells obtained from other, non-cutaneous tissues showed two forms of collagen alpha 1(III) chains, a normal and a slow migrating, mutant form. Further analysis confirmed that the type III collagen molecules containing mutant alpha chains which were overmodified had a lower thermal stability and were poorly secreted into the extracellular medium. The protein defect was mapped by in situ cyanogen bromide digestion and was located in alpha 1(III) CB9, the C-terminal peptide of the collagen triple helix. This study shows that non-cutaneous connective tissues can be a useful source for the study of type III collagen defects in patients with EDS type IV. Images PMID:1619632

  8. Resonance electron attachment to plant hormones and its likely connection with biochemical processes

    NASA Astrophysics Data System (ADS)

    Pshenichnyuk, Stanislav A.; Modelli, Alberto

    2014-01-01

    Gas-phase formation of temporary negative ion states via resonance attachment of low-energy (0-6 eV) electrons into vacant molecular orbitals of salicylic acid (I) and its derivatives 3-hydroxy- (II) and 4-hydroxybenzoic acid (III), 5-cloro salicylic acid (IV) and methyl salicylate (V) was investigated for the first time by electron transmission spectroscopy. The description of their empty-level structures was supported by density functional theory and Hartree-Fock calculations, using empirically calibrated linear equations to scale the calculated virtual orbital energies. Dissociative electron attachment spectroscopy (DEAS) was used to measure the fragment anion yields generated through dissociative decay channels of the parent molecular anions of compounds I-V, detected with a mass filter as a function of the incident electron energy in the 0-14 eV energy range. The most intense negative fragment produced by DEA to isomers I-III is the dehydrogenated molecular anion [M-H]-, mainly formed at incident electron energies around 1 eV. The vertical and adiabatic electron affinities were evaluated at the B3LYP/6-31+G(d) level as the anion/neutral total energy difference. The same theoretical method was also used for evaluation of the thermodynamic energy thresholds for production of the negative fragments observed in the DEA spectra. The gas-phase DEAS data can provide support for biochemical reaction mechanisms in vivo.

  9. Resonance electron attachment to plant hormones and its likely connection with biochemical processes

    SciTech Connect

    Pshenichnyuk, Stanislav A.; Modelli, Alberto

    2014-01-21

    Gas-phase formation of temporary negative ion states via resonance attachment of low-energy (0–6 eV) electrons into vacant molecular orbitals of salicylic acid (I) and its derivatives 3-hydroxy- (II) and 4-hydroxybenzoic acid (III), 5-cloro salicylic acid (IV) and methyl salicylate (V) was investigated for the first time by electron transmission spectroscopy. The description of their empty-level structures was supported by density functional theory and Hartree-Fock calculations, using empirically calibrated linear equations to scale the calculated virtual orbital energies. Dissociative electron attachment spectroscopy (DEAS) was used to measure the fragment anion yields generated through dissociative decay channels of the parent molecular anions of compounds I–V, detected with a mass filter as a function of the incident electron energy in the 0–14 eV energy range. The most intense negative fragment produced by DEA to isomers I–III is the dehydrogenated molecular anion [M–H]{sup −}, mainly formed at incident electron energies around 1 eV. The vertical and adiabatic electron affinities were evaluated at the B3LYP/6-31+G(d) level as the anion/neutral total energy difference. The same theoretical method was also used for evaluation of the thermodynamic energy thresholds for production of the negative fragments observed in the DEA spectra. The gas-phase DEAS data can provide support for biochemical reaction mechanisms in vivo.

  10. Resonance electron attachment to plant hormones and its likely connection with biochemical processes.

    PubMed

    Pshenichnyuk, Stanislav A; Modelli, Alberto

    2014-01-21

    Gas-phase formation of temporary negative ion states via resonance attachment of low-energy (0-6 eV) electrons into vacant molecular orbitals of salicylic acid (I) and its derivatives 3-hydroxy- (II) and 4-hydroxybenzoic acid (III), 5-cloro salicylic acid (IV) and methyl salicylate (V) was investigated for the first time by electron transmission spectroscopy. The description of their empty-level structures was supported by density functional theory and Hartree-Fock calculations, using empirically calibrated linear equations to scale the calculated virtual orbital energies. Dissociative electron attachment spectroscopy (DEAS) was used to measure the fragment anion yields generated through dissociative decay channels of the parent molecular anions of compounds I-V, detected with a mass filter as a function of the incident electron energy in the 0-14 eV energy range. The most intense negative fragment produced by DEA to isomers I-III is the dehydrogenated molecular anion [M-H](-), mainly formed at incident electron energies around 1 eV. The vertical and adiabatic electron affinities were evaluated at the B3LYP/6-31+G(d) level as the anion/neutral total energy difference. The same theoretical method was also used for evaluation of the thermodynamic energy thresholds for production of the negative fragments observed in the DEA spectra. The gas-phase DEAS data can provide support for biochemical reaction mechanisms in vivo.

  11. Biochemical investigation of cypermethrin toxicity in rabbits.

    PubMed

    Dahamna, S; Harzallah, D; Guemache, A; Sekfali, N

    2009-01-01

    cypermethrin on the erythropoiesis. An increase of plasma enzyme activities in GOT, GPT and CPK were recorded, explain a high energy-generating product. An increase, in the plasma enzyme activity in Alkaline phosphatase, related to their role in the cell permeability. The histopathological results showed lesions and morphological changes of hepato-cellular, fibrosis and appearance of inflammatory infiltrate, confirmed disturbances of the biochemical parameters. These changes were much underlines during the animal toxicity.

  12. Reduction, integration and emergence in biochemical networks.

    PubMed

    Ricard, Jacques

    2004-12-01

    Most studies of molecular cell biology are based upon a process of decomposition of complex biological systems into their components, followed by the study of these components. The aim of the present paper is to discuss, on a physical basis, the internal logic of this process of reduction. The analysis is performed on simple biological systems, namely protein and metabolic networks. A multi-sited protein that binds two ligands x and y can be considered the simplest possible biochemical network. The organization of this network can be described through a comparison of three systems, i.e. XY, X and Y. X and Y are component sub-systems that collect states x(i) and y(j), respectively, i.e. protein states that have bound either i molecules of x (whether or not these states have also bound y), or j molecules of y (whether or not these states have bound x). XY is a system made up of the specific association of X and Y that collects states x(i)y(j). One can define mean self-informations per node of the network, , and . Reduction of the system XY into its components is possible if, and only if, ,is equal to the sum of and . If is smaller than the sum of and , the system is integrated, for it has less self-information than the set of its components X and Y. It can also occur that , be larger than the sum of and . Hence, the system XY displays negative integration and emergence of self-information relative to its components X and Y. Such a system is defined as complex. Positive or negative integration of the system implies it cannot be reduced to its components. The degree of integration can be measured by a function , called mutual information of integration. In the case of enzyme networks, emergence of self-information is associated with emergence of catalytic activity. Moreover, if the enzyme reaction is part of a metabolic sequence, its mutual information of integration can be

  13. Biochemical observation during 28 days of space flight

    NASA Technical Reports Server (NTRS)

    Leach, C. S.; Kambaut, P. C.

    1975-01-01

    With the completion of the 28-day flight of Skylab 2, the sum of biochemical data on human reaction to the weightless environment was significantly extended both quantitatively and qualitatively. The biochemical studies were divided into two broad categories. One group included the more routine blood studies similar to those used in everyday medical practice. The second category encompassed those analyses used to investigate more thoroughly the endocrinological and fluid changes first seen in the crewmembers following the Gemini, Apollo, and Soviet missions. Significant biochemical changes were observed that varied in magnitude and direction, but all disappeared shortly after return to earth. Most of changes indicate successful adaptation by the body to the combined stresses of weightlessness. Results of the biochemical observation are presented in the form of data tables and graphs.

  14. Aquatic ecological biochemical investigations in the Lake Baikal region

    SciTech Connect

    Timofeeva, S.S.; Kozhova, O.M.

    1986-07-01

    The authors maintain that at the current level of investigations a constructive solution of the problem of protecting aquatic ecosystems is possible only on the basis of a thorough study of biochemical mechanisms of the interaction of biota and pollutants. They believe that in the program of investigations in the Baikal region, with consideration of the easy vulnerability of the aquatic ecosystems, ecological biochemical investigations should occupy one of the leading places. The authors suggest a method for the screening of xenobiotics, consisting of xenobiotics; chemical investigations; biochemical investigations of the properties of xenobiotics, and toxicological investigations of xenobiotics. The differences in the elimination of xenobiotics are considerable due to the species and biochemical characteristics of hydrophytes and chemical structure of the investigated toxicants. The results obtained in experiments with cyanide compounds are of considerable interest, since cyanides, the strongest poisons of animals, prove to be little toxic for higher aquatic plants and algae.

  15. 2011 Biomass Program Platform Peer Review: Biochemical Conversion

    SciTech Connect

    Pezzullo, Leslie

    2012-02-01

    This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the 2011 U.S. Department of Energy Biomass Program’s Biochemical Conversion Platform Review meeting.

  16. A view of the history of biochemical engineering.

    PubMed

    Katzen, R; Tsao, G T

    2000-01-01

    The authors present a view of biochemical engineering by describing their personal interests and experience over the years involving mostly conversion of lignocellulosics into fuels and chemicals and the associated engineering subjects.

  17. Optical chemical and biochemical sensors: new trends (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Baldini, F.; Giannetti, A.

    2005-06-01

    Chemical and biochemical sensing is under the extensive research all over the world and many chemical and biochemical sensors are finding increasing number of applications in industry, environmental monitoring, medicine, biomedicine and chemical analysis. This is evidenced by each-year-growing number of international scientific conferences, in which advances in the field of the sensors are reported. One of the main reason why only a few sensors reach the international market, notwithstanding the high number of laboratory prototype described in many peer reviewed papers, lies in the fact that a biochemical sensor is a highly interdisciplinary "object" the realization of which requires the team work of scientists coming from different areas such as chemistry, physics, optoelectronics, engineering, biochemistry, and medicine. And this peculiarity is not easily found in the research teams. In the present paper, the fundamental bases of chemical and biochemical optical sensing are summarised and the new trends are described.

  18. Laetrile: A Study of Its Physicochemical and Biochemical Properties

    PubMed Central

    Levi, Leo; French, W. N.; Bickis, I. J.; Henderson, I. W. D.

    1965-01-01

    A study was made of the composition and biochemical behaviour of the drug, Laetrile, distributed for clinical trial in the United States and Canada. It was established that the Canadian and the American product are different pharmaceutical formulations, displaying different physicochemical and biochemical properties. The investigation demonstrated, furthermore, that neither preparation can be considered as a palliative in cancer therapy on the basis of the biological rationale advanced by their manufacturers. ImagesFig. 3 PMID:14281087

  19. Evolution of plant senescence

    PubMed Central

    Thomas, Howard; Huang, Lin; Young, Mike; Ougham, Helen

    2009-01-01

    -related genes allow a framework to be constructed of decisive events in the evolution of the senescence syndrome of modern land-plants. Combining phylogenetic, comparative sequence, gene expression and morphogenetic information leads to the conclusion that biochemical, cellular, integrative and adaptive systems were progressively added to the ancient primary core process of senescence as the evolving plant encountered new environmental and developmental contexts. PMID:19602260

  20. Energy-based analysis of biochemical cycles using bond graphs.

    PubMed

    Gawthrop, Peter J; Crampin, Edmund J

    2014-11-08

    Thermodynamic aspects of chemical reactions have a long history in the physical chemistry literature. In particular, biochemical cycles require a source of energy to function. However, although fundamental, the role of chemical potential and Gibb's free energy in the analysis of biochemical systems is often overlooked leading to models which are physically impossible. The bond graph approach was developed for modelling engineering systems, where energy generation, storage and transmission are fundamental. The method focuses on how power flows between components and how energy is stored, transmitted or dissipated within components. Based on the early ideas of network thermodynamics, we have applied this approach to biochemical systems to generate models which automatically obey the laws of thermodynamics. We illustrate the method with examples of biochemical cycles. We have found that thermodynamically compliant models of simple biochemical cycles can easily be developed using this approach. In particular, both stoichiometric information and simulation models can be developed directly from the bond graph. Furthermore, model reduction and approximation while retaining structural and thermodynamic properties is facilitated. Because the bond graph approach is also modular and scaleable, we believe that it provides a secure foundation for building thermodynamically compliant models of large biochemical networks.

  1. Energy-based analysis of biochemical cycles using bond graphs

    PubMed Central

    Gawthrop, Peter J.; Crampin, Edmund J.

    2014-01-01

    Thermodynamic aspects of chemical reactions have a long history in the physical chemistry literature. In particular, biochemical cycles require a source of energy to function. However, although fundamental, the role of chemical potential and Gibb's free energy in the analysis of biochemical systems is often overlooked leading to models which are physically impossible. The bond graph approach was developed for modelling engineering systems, where energy generation, storage and transmission are fundamental. The method focuses on how power flows between components and how energy is stored, transmitted or dissipated within components. Based on the early ideas of network thermodynamics, we have applied this approach to biochemical systems to generate models which automatically obey the laws of thermodynamics. We illustrate the method with examples of biochemical cycles. We have found that thermodynamically compliant models of simple biochemical cycles can easily be developed using this approach. In particular, both stoichiometric information and simulation models can be developed directly from the bond graph. Furthermore, model reduction and approximation while retaining structural and thermodynamic properties is facilitated. Because the bond graph approach is also modular and scaleable, we believe that it provides a secure foundation for building thermodynamically compliant models of large biochemical networks. PMID:25383030

  2. [Fifty years of cooperation--FEBS and Polish Biochemical Society].

    PubMed

    Barańska, Jolanta

    2014-01-01

    This year, the Federation of European Biochemical Societies (FEBS) celebrates its 50th anniversary. The Polish Biochemical Society, represented by the Society's President, Kazimierz Zakrzewski, was a founding member of the organization. The text presents a history of collaboration between FEBS and Polish Biochemical Society, the participation of Polish Biochemical Society members in different FEBS activities, as well as the role they played in running the Federation. Author describes FEBS Congresses which taken place in Warsaw, the first 3rd FEBS Meeting in 1966 and then 29th Congress in 2004. The profiles of Jakub Karol Parnas, the founding father of the Polish biochemistry and some crucial Presidents of the Society, are also presented. The text describes Parnas Conferences, organized jointly by Polish and Ukrainian Biochemical Societies from 1996, and growing from 2011 into three-nation event with participation of Ukrainian, Israeli and Polish scientists, largely due to significant help from FEBS. Summarizing the last few years, author judge the cooperation between the Federation and the Polish Biochemical Society as optimal.

  3. Discriminating model for diagnosis of basal cell carcinoma and melanoma in vitro based on the Raman spectra of selected biochemicals

    NASA Astrophysics Data System (ADS)

    Silveira, Landulfo; Silveira, Fabrício Luiz; Bodanese, Benito; Zângaro, Renato Amaro; Pacheco, Marcos Tadeu T.

    2012-07-01

    Raman spectroscopy has been employed to identify differences in the biochemical constitution of malignant [basal cell carcinoma (BCC) and melanoma (MEL)] cells compared to normal skin tissues, with the goal of skin cancer diagnosis. We collected Raman spectra from compounds such as proteins, lipids, and nucleic acids, which are expected to be represented in human skin spectra, and developed a linear least-squares fitting model to estimate the contributions of these compounds to the tissue spectra. We used a set of 145 spectra from biopsy fragments of normal (30 spectra), BCC (96 spectra), and MEL (19 spectra) skin tissues, collected using a near-infrared Raman spectrometer (830 nm, 50 to 200 mW, and 20 s exposure time) coupled to a Raman probe. We applied the best-fitting model to the spectra of biochemicals and tissues, hypothesizing that the relative spectral contribution of each compound to the tissue Raman spectrum changes according to the disease. We verified that actin, collagen, elastin, and triolein were the most important biochemicals representing the spectral features of skin tissues. A classification model applied to the relative contribution of collagen III, elastin, and melanin using Euclidean distance as a discriminator could differentiate normal from BCC and MEL.

  4. Discriminating model for diagnosis of basal cell carcinoma and melanoma in vitro based on the Raman spectra of selected biochemicals.

    PubMed

    Silveira, Landulfo; Silveira, Fabrício Luiz; Bodanese, Benito; Zângaro, Renato Amaro; Pacheco, Marcos Tadeu T

    2012-07-01

    Raman spectroscopy has been employed to identify differences in the biochemical constitution of malignant [basal cell carcinoma (BCC) and melanoma (MEL)] cells compared to normal skin tissues, with the goal of skin cancer diagnosis. We collected Raman spectra from compounds such as proteins, lipids, and nucleic acids, which are expected to be represented in human skin spectra, and developed a linear least-squares fitting model to estimate the contributions of these compounds to the tissue spectra. We used a set of 145 spectra from biopsy fragments of normal (30 spectra), BCC (96 spectra), and MEL (19 spectra) skin tissues, collected using a near-infrared Raman spectrometer (830 nm, 50 to 200 mW, and 20 s exposure time) coupled to a Raman probe. We applied the best-fitting model to the spectra of biochemicals and tissues, hypothesizing that the relative spectral contribution of each compound to the tissue Raman spectrum changes according to the disease. We verified that actin, collagen, elastin, and triolein were the most important biochemicals representing the spectral features of skin tissues. A classification model applied to the relative contribution of collagen III, elastin, and melanin using Euclidean distance as a discriminator could differentiate normal from BCC and MEL.

  5. Effects of Khaya senegalensis leaves on performance, carcass traits, hemtological and biochemical parameters in rabbits

    PubMed Central

    Abdel-Wareth, A. A. A.; Hammad, Seddik; Ahmed, Hassan

    2014-01-01

    One of the challenges facing farmers today is to ensure adequate integration of natural resources into animal feeds. The aim of the present study is to evaluate the effects of Khaya senegalensis (KS) leaves on the performance of growing male rabbits, carcass traits and biochemical as well as hematological parameters. Thirty New Zealand White male growing rabbits were randomly divided into 3 groups (10 rabbits per group). Group I (control) received standard rabbit diet. Rabbits in group II and group III were fed standard rabbit diet supplemented with 35 % and 65 % KS leaves, respectively. All rabbits were fed daily for 25 days. The performance parameters and carcass criteria, including daily body weight gain, final body weight, and the percentage of dressing, were increased in rabbits fed 35 % KS when compared to the control group. Kidney and liver weight ratios increased significantly in group II but dropped in group III. Furthermore, liver enzymes - alanine aminotransferase and aspartate transaminase and kidney function parameters - urea, and creatinine - increased in both group II (significant P<0.05) and in group III (significant P<0.01) when compared to the control group. Moreover, KS leaves induced a significant increase (P<0.05) in the total white blood cell count, the percentage of granulocytes and the platelet count; whereas, the percentage of lymphocytes, red blood cell count, hemoglobin content, mean corpuscular hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin concentration were not statistically significantly changed. This study demonstrates that the performance parameters and carcass traits are improved by the replacement of rabbit's diet with KS leaves. However, KS leaves may adversely affect liver and kidney function in a dose-dependent manner. Therefore, further studies are required to elucidate the maximum tolerable and toxic, as well as lethal doses, and to isolate the pharmacologically active components from KS leaves. PMID

  6. [Biochemical and molecular characterization of gliadins].

    PubMed

    Qi, P F; Wei, Y M; Yue, Y W; Yan, Z H; Zheng, Y L

    2006-01-01

    Gliadins account for about 40-50% of the total proteins in wheat seeds and play an important role on the nutritional and processing quality of flour. Usually, gliadins could be divided into alpha- (alpha/beta-), gamma- and omega-groups, whereas the low-molecular-weigh (LMW) gliadins were novel seed storage proteins. The low-molecular-weight glutenin subunits (LMW-GSs) were also designated as gliadins in a few literatures. The genes encoding gliadins were mainly located on the short arms of group 6 and group 1 chromosomes, and not evenly distributed. Repetitive sequences covered most of un-coding regions, which attributed greatly to the evolution of wheat genome. Primary structure of each gliadin has been divided into several domains, and the long repetitive domains consisted of peptide motifs. Conserved cysteine residues mainly formed intramolecular disulphide bonds. The rare potential intermolecular disulphide bonds and the long repetitive domains played an important role in the wheat flour quality. There was a general idea that gliadin genes, even prolamin genes, have a common origin and subsequent divergence lead to the gene polymorphism. The gamma-gliadins have been considered to be the most ancient of the wheat prolamin family. Several elements in the 5'-flanking (e.g. CAAT and TATA box) and the 3'-flanking sequences had been detected, which had been shown necessary for the proper expression of gliadins.

  7. A molecular description of the evolution of resistance

    NASA Technical Reports Server (NTRS)

    Ordoukhanian, P.; Joyce, G. F.

    1999-01-01

    BACKGROUND: In vitro evolution has been used to obtain nucleic acid molecules with interesting functional properties. The evolution process usually is carried out in a stepwise manner, involving successive rounds of selection, amplification and mutation. Recently, a continuous in vitro evolution system was devised for RNAs that catalyze the ligation of oligonucleotide substrates, allowing the evolution of catalytic function to be studied in real time. RESULTS: Continuous in vitro evolution of an RNA ligase ribozyme was carried out in the presence of a DNA enzyme that was capable of cleaving, and thereby inactivating, the ribozyme. The DNA concentration was increased steadily over 33.5 hours of evolution, reaching a final concentration that would have been sufficient to inactivate the starting population in one second. The evolved population of ribozymes developed resistance to the DNA enzyme, reducing their vulnerability to cleavage by 2000-fold but retaining their own catalytic function. Based on sequencing and kinetic analysis of the ribozymes, two mechanisms are proposed for this resistance. One involves three nucleotide substitutions, together with two compensatory mutations, that alter the site at which the DNA enzyme binds the ribozyme. The other involves enhancement of the ribozyme's ability to bind its own substrate in a way that protects it from cleavage by the DNA enzyme. CONCLUSIONS: The ability to direct the evolution of an enzyme's biochemical properties in response to the behavior of another macromolecule provides insight into the evolution of resistance and may be useful in developing enzymes with novel or enhanced function.

  8. Biochemical and genetic engineering strategies to enhance hydrogen production in photosynthetic algae and cyanobacteria.

    PubMed

    Srirangan, Kajan; Pyne, Michael E; Perry Chou, C

    2011-09-01

    As an energy carrier, hydrogen gas is a promising substitute to carbonaceous fuels owing to its superb conversion efficiency, non-polluting nature, and high energy content. At present, hydrogen is predominately synthesized via chemical reformation of fossil fuels. While various biological methods have been extensively explored, none of them is justified as economically feasible. A sustainable platform for biological production of hydrogen will certainly impact the biofuel market. Among a selection of biological systems, algae and cyanobacteria have garnered major interests as potential cell factories for hydrogen production. In conjunction with photosynthesis, these organisms utilize inexpensive inorganic substrates and solar energy for simultaneous biosynthesis and hydrogen evolution. However, the hydrogen yield associated with these organisms remains far too low to compete with the existing chemical systems. This article reviews recent advances of biochemical, bioprocess, and genetic engineering strategies in circumventing technological limitations to hopefully improve the applicative potential of these photosynthetic hydrogen production systems.

  9. Nonprevalence of biochemical fossils in kerogen from pre-Phanerozoic sediments

    PubMed Central

    Leventhal, Joel; Suess, Stephen E.; Cloud, Preston

    1975-01-01

    Evidence of biochemical and geochemical evolution was sought in insoluble carbonaceous matter from 30 selected pre-Phanerozoic sediments ranging in age from about 3.8 to about 0.7 × 109 years. The carbon isotope ratios observed were in the range of -20 to -32 per mil with reference to the Peedee belemnite standard, similar to those previously reported. No systematic trends are obvious to us. Stepwise pyrolysis-gas-chromatography showed only molecules with fewer than 8 carbon atoms at the level of sensitivity of 10-9 g of organics in a 10 mg rock sample. Carbon, hydrogen, and nitrogen analyses showed noncarbonate carbon from less than 0.1% to more than 3%, with very small amounts of N. The H/C (atomic) ratios on HCl-leached and HF-treated samples were generally less than 0.3. Evidence of low pyrolysis yields (micro-analysis) and low H/C atomic ratios (macro-analysis) implies that the carbonaceous solids in even the least metamorphosed of these ancient sediments have evolved far toward amorphous carbon or graphite and do not yield useful “biochemical fossils.” PMID:16592291

  10. Phylogenetic, Molecular, and Biochemical Characterization of Caffeic Acid o-Methyltransferase Gene Family in Brachypodium distachyon

    PubMed Central

    Wu, Xianting; Wu, Jiajie; Luo, Yangfan; Bragg, Jennifer; Anderson, Olin; Vogel, John; Gu, Yong Q.

    2013-01-01

    Caffeic acid o-methyltransferase (COMT) is one of the important enzymes controlling lignin monomer production in plant cell wall synthesis. Analysis of the genome sequence of the new grass model Brachypodium distachyon identified four COMT gene homologs, designated as BdCOMT1, BdCOMT2, BdCOMT3, and BdCOMT4. Phylogenetic analysis suggested that they belong to the COMT gene family, whereas syntenic analysis through comparisons with rice and sorghum revealed that BdCOMT4 on Chromosome 3 is the orthologous copy of the COMT genes well characterized in other grass species. The other three COMT genes are unique to Brachypodium since orthologous copies are not found in the collinear regions of rice and sorghum genomes. Expression studies indicated that all four Brachypodium COMT genes are transcribed but with distinct patterns of tissue specificity. Full-length cDNAs were cloned in frame into the pQE-T7 expression vector for the purification of recombinant Brachypodium COMT proteins. Biochemical characterization of enzyme activity and substrate specificity showed that BdCOMT4 has significant effect on a broad range of substrates with the highest preference for caffeic acid. The other three COMTs had low or no effect on these substrates, suggesting that a diversified evolution occurred on these duplicate genes that not only impacted their pattern of expression, but also altered their biochemical properties. PMID:23431288

  11. Genetic and Biochemical Diversity among Valeriana jatamansi Populations from Himachal Pradesh

    PubMed Central

    Singh, Sunil Kumar; Katoch, Rajan; Kapila, Rakesh Kumar

    2015-01-01

    Valeriana jatamansi Jones is an important medicinal plant that grows wild in Himachal Pradesh, India. Molecular and biochemical diversity among 13 natural populations from Himachal Pradesh was assessed using RAPD and GC-MS to know the extent of existing variation. A total of seven genetically diverse groups have been identified based on RAPD analysis which corroborated well with the analysis based on chemical constituents. The essential oil yield ranged from 0.6% to 1.66% (v/w). A negative correlation between patchouli alcohol and viridiflorol, the two major valued constituents, limits the scope of their simultaneous improvement. However, other few populations like Chamba-II and Kandi-I were found promising for viridiflorol and patchouli alcohol, respectively. The analysis of chemical constitution of oil of the populations from a specific region revealed predominance of specific constituents indicating possibility of their collection/selection for specific end uses like phytomedicines. The prevalence of genetically diverse groups along with sufficient chemical diversity in a defined region clearly indicates the role of ecology in the maintenance of evolution of this species. Sufficient molecular and biochemical diversity detected among natural populations of this species will form basis for the future improvement. PMID:25741533

  12. How biochemical constraints of cellular growth shape evolutionary adaptations in metabolism.

    PubMed

    Berkhout, Jan; Bosdriesz, Evert; Nikerel, Emrah; Molenaar, Douwe; de Ridder, Dick; Teusink, Bas; Bruggeman, Frank J

    2013-06-01

    Evolutionary adaptations in metabolic networks are fundamental to evolution of microbial growth. Studies on unneeded-protein synthesis indicate reductions in fitness upon nonfunctional protein synthesis, showing that cell growth is limited by constraints acting on cellular protein content. Here, we present a theory for optimal metabolic enzyme activity when cells are selected for maximal growth rate given such growth-limiting biochemical constraints. We show how optimal enzyme levels can be understood to result from an enzyme benefit minus cost optimization. The constraints we consider originate from different biochemical aspects of microbial growth, such as competition for limiting amounts of ribosomes or RNA polymerases, or limitations in available energy. Enzyme benefit is related to its kinetics and its importance for fitness, while enzyme cost expresses to what extent resource consumption reduces fitness through constraint-induced reductions of other enzyme levels. A metabolic fitness landscape is introduced to define the fitness potential of an enzyme. This concept is related to the selection coefficient of the enzyme and can be expressed in terms of its fitness benefit and cost.

  13. III-Nitride Nanowire Lasers

    SciTech Connect

    Wright, Jeremy Benjamin

    2014-07-01

    In recent years there has been a tremendous interest in nanoscale optoelectronic devices. Among these devices are semiconductor nanowires whose diameters range from 10-100 nm. To date, nanowires have been grown using many semiconducting material systems and have been utilized as light emitting diodes, photodetectors, and solar cells. Nanowires possess a relatively large index contrast relative to their dielectric environment and can be used as lasers. A key gure of merit that allows for nanowire lasing is the relatively high optical con nement factor. In this work, I discuss the optical characterization of 3 types of III-nitride nanowire laser devices. Two devices were designed to reduce the number of lasing modes to achieve singlemode operation. The third device implements low-group velocity mode lasing with a photonic crystal constructed of an array of nanowires. Single-mode operation is necessary in any application where high beam quality and single frequency operation is required. III-Nitride nanowire lasers typically operate in a combined multi-longitudinal and multi-transverse mode state. Two schemes are introduced here for controlling the optical modes and achieving single-mode op eration. The rst method involves reducing the diameter of individual nanowires to the cut-o condition, where only one optical mode propagates in the wire. The second method employs distributed feedback (DFB) to achieve single-mode lasing by placing individual GaN nanowires onto substrates with etched gratings. The nanowire-grating substrate acted as a distributed feedback mirror producing single mode operation at 370 nm with a mode suppression ratio (MSR) of 17 dB. The usage of lasers for solid state lighting has the potential to further reduce U.S. lighting energy usage through an increase in emitter e ciency. Advances in nanowire fabrication, speci cally a two-step top-down approach, have allowed for the demonstration of a multi-color array of lasers on a single chip that emit

  14. III-nitride nanowire lasers

    NASA Astrophysics Data System (ADS)

    Wright, Jeremy Benjamin

    In recent years there has been a tremendous interest in nanoscale optoelectronic devices. Among these devices are semiconductor nanowires whose diameters range from 10-100 nm. To date, nanowires have been grown using many semiconducting material systems and have been utilized as light emitting diodes, photodetectors, and solar cells. Nanowires possess a relatively large index contrast relative to their dielectric environment and can be used as lasers. A key figure of merit that allows for nanowire lasing is the relatively high optical confinement factor. In this work, I discuss the optical characterization of 3 types of III-nitride nanowire laser devices. Two devices were designed to reduce the number of lasing modes to achieve single-mode operation. The third device implements low-group velocity mode lasing with a photonic crystal constructed of an array of nanowires. Single-mode operation is necessary in any application where high beam quality and single frequency operation is required. III-Nitride nanowire lasers typically operate in a combined multi-longitudinal and multi-transverse mode state. Two schemes are introduced here for controlling the optical modes and achieving single-mode operation. The first method involves reducing the diameter of individual nanowires to the cut-off condition, where only one optical mode propagates in the wire. The second method employs distributed feedback (DFB) to achieve single-mode lasing by placing individual GaN nanowires onto substrates with etched gratings. The nanowire-grating substrate acted as a distributed feedback mirror producing single mode operation at 370 nm with a mode suppression ratio (MSR) of 17 dB. The usage of lasers for solid state lighting has the potential to further reduce U.S. lighting energy usage through an increase in emitter efficiency. Advances in nanowire fabrication, specifically a two-step top-down approach, have allowed for the demonstration of a multi-color array of lasers on a single chip

  15. Type III protein secretion systems in bacterial pathogens of animals and plants.

    PubMed

    Hueck, C J

    1998-06-01

    Various gram-negative animal and plant pathogens use a novel, sec-independent protein secretion system as a basic virulence mechanism. It is becoming increasingly clear that these so-called type III secretion systems inject (translocate) proteins into the cytosol of eukaryotic cells, where the translocated proteins facilitate bacterial pathogenesis by specifically interfering with host cell signal transduction and other cellular processes. Accordingly, some type III secretion systems are activated by bacterial contact with host cell surfaces. Individual type III secretion systems direct the secretion and translocation of a variety of unrelated proteins, which account for species-specific pathogenesis phenotypes. In contrast to the secreted virulence factors, most of the 15 to 20 membrane-associated proteins which constitute the type III secretion apparatus are conserved among different pathogens. Most of the inner membrane components of the type III secretion apparatus show additional homologies to flagellar biosynthetic proteins, while a conserved outer membrane factor is similar to secretins from type II and other secretion pathways. Structurally conserved chaperones which specifically bind to individual secreted proteins play an important role in type III protein secretion, apparently by preventing premature interactions of the secreted factors with other proteins. The genes encoding type III secretion systems are clustered, and various pieces of evidence suggest that these systems have been acquired by horizontal genetic transfer during evolution. Expression of type III secretion systems is coordinately regulated in response to host environmental stimuli by networks of transcription factors. This review comprises a comparison of the structure, function, regulation, and impact on host cells of the type III secretion systems in the animal pathogens Yersinia spp., Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhimurium, enteropathogenic Escherichia coli

  16. Spectroscopic identification of type 2 quasars at z < 1 in SDSS-III/BOSS

    NASA Astrophysics Data System (ADS)

    Yuan, Sihan; Strauss, Michael A.; Zakamska, Nadia L.

    2016-10-01

    The physics and demographics of type 2 quasars remain poorly understood, and new samples of such objects selected in a variety of ways can give insight into their physical properties, evolution, and relationship to their host galaxies. We present a sample of 2758 type 2 quasars at z ≲ 1 from the Sloan Digital Sky Survey-III (SDSS-III)/Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic data base, selected on the basis of their emission-line properties. We probe the luminous end of the population by requiring the rest-frame equivalent width of [O III] to be >100 Å. We distinguish our objects from star-forming galaxies and type 1 quasars using line widths, standard emission line ratio diagnostic diagrams at z < 0.52 and detection of [Ne V]λ3426 Å at z > 0.52. The majority of our objects have [O III] luminosities in the range 1.2 × 1042-3.8 × 1043 erg s-1 and redshifts between 0.4 and 0.65. Our sample includes over 400 type 2 quasars with incorrectly measured redshifts in the BOSS data base; such objects often show kinematic substructure or outflows in the [O III] line. The majority of the sample has counterparts in the Wide-field Infrared Survey Explorer survey, with median infrared luminosity νLν[12 μm] = 4.2 × 1044 erg s- 1. Only 34 per cent of the newly identified type 2 quasars would be selected by infrared colour cuts designed to identify obscured active nuclei, highlighting the difficulty of identifying complete samples of type 2 quasars. We make public the multi-Gaussian decompositions of all [O III] profiles for the new sample and for 568 type 2 quasars from SDSS I/II, together with non-parametric measures of the [O III] line profile shapes. We also identify over 600 candidate double-peaked [O III] profiles.

  17. Type III Protein Secretion Systems in Bacterial Pathogens of Animals and Plants

    PubMed Central

    Hueck, Christoph J.

    1998-01-01

    Various gram-negative animal and plant pathogens use a novel, sec-independent protein secretion system as a basic virulence mechanism. It is becoming increasingly clear that these so-called type III secretion systems inject (translocate) proteins into the cytosol of eukaryotic cells, where the translocated proteins facilitate bacterial pathogenesis by specifically interfering with host cell signal transduction and other cellular processes. Accordingly, some type III secretion systems are activated by bacterial contact with host cell surfaces. Individual type III secretion systems direct the secretion and translocation of a variety of unrelated proteins, which account for species-specific pathogenesis phenotypes. In contrast to the secreted virulence factors, most of the 15 to 20 membrane-associated proteins which constitute the type III secretion apparatus are conserved among different pathogens. Most of the inner membrane components of the type III secretion apparatus show additional homologies to flagellar biosynthetic proteins, while a conserved outer membrane factor is similar to secretins from type II and other secretion pathways. Structurally conserved chaperones which specifically bind to individual secreted proteins play an important role in type III protein secretion, apparently by preventing premature interactions of the secreted factors with other proteins. The genes encoding type III secretion systems are clustered, and various pieces of evidence suggest that these systems have been acquired by horizontal genetic transfer during evolution. Expression of type III secretion systems is coordinately regulated in response to host environmental stimuli by networks of transcription factors. This review comprises a comparison of the structure, function, regulation, and impact on host cells of the type III secretion systems in the animal pathogens Yersinia spp., Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhimurium, enteropathogenic Escherichia coli

  18. Understanding Evolution: An Evolution Website for Teachers

    ERIC Educational Resources Information Center

    Scotchmoor, Judy; Janulaw, Al

    2005-01-01

    While many states are facing challenges to the teaching of evolution in their science classrooms, the University of California Museum of Paleontology, working with the National Center for Science Education, has developed a useful web-based resource for science teachers of all grade- and experience-levels. Understanding Evolution (UE) was developed…

  19. The evolution of rod photoreceptors.

    PubMed

    Morshedian, Ala; Fain, Gordon L

    2017-04-05

    Photoreceptors in animals are generally of two kinds: the ciliary or c-type and the rhabdomeric or r-type. Although ciliary photoreceptors are found in many phyla, vertebrates seem to be unique in having two distinct kinds which together span the entire range of vision, from single photons to bright light. We ask why the principal photoreceptors of vertebrates are ciliary and not rhabdomeric, and how rods evolved from less sensitive cone-like photoreceptors to produce our duplex retina. We suggest that the principal advantage of vertebrate ciliary receptors is that they use less ATP than rhabdomeric photoreceptors. This difference may have provided sufficient selection pressure for the development of a completely ciliary eye. Although many of the details of rod evolution are still uncertain, present evidence indicates that (i) rods evolved very early before the split between the jawed and jawless vertebrates, (ii) outer-segment discs make no contribution to rod sensitivity but may have evolved to increase the efficiency of protein renewal, and (iii) evolution of the rod was incremental and multifaceted, produced by the formation of several novel protein isoforms and by changes in protein expression, with no one alteration having more than a few-fold effect on transduction activation or inactivation.This article is part of the themed issue 'Vision in dim light'.

  20. DOE/NNSA perspective safeguard by design: GEN III/III+ light water reactors and beyond

    SciTech Connect

    Pan, Paul Y

    2010-12-10

    An overview of key issues relevant to safeguards by design (SBD) for GEN III/IV nuclear reactors is provided. Lessons learned from construction of typical GEN III+ water reactors with respect to SBD are highlighted. Details of SBD for safeguards guidance development for GEN III/III+ light water reactors are developed and reported. This paper also identifies technical challenges to extend SBD including proliferation resistance methodologies to other GEN III/III+ reactors (except HWRs) and GEN IV reactors because of their immaturity in designs.

  1. [Biochemical selenocysteine synthesis and the phylogenic study].

    PubMed

    Mizutani, Takaharu; Osaka, Takashi; Fujiwara, Toshinobu; Shahidzzman, M

    2008-07-01

    Selenium (Se) is an essential trace element. Se is found as selenocysteine (Sec) in Se-proteins. Sec is the 21(st) amino acid, because Sec has its tRNA, the codon UGA and those components in its translational machinery. Sec UGA codon shares with major stop codon UGA. We purified Sec synthesizing enzymes, such as seryl-tRNA synthetase (SerRS), Sec synthetase (SecS) and selenophosphate synthetase (SePS). I described the procedures to prepare Sec tRNA, SerRS, SecS, SePS and [(75)Se]H(2)Se in detail. We clarified that SecS composed of two proteins, SecSalpha and SecSbeta. Sec synthesizing and incorporating systems present in Monela, Animalia and Protoctista but not in Plantae and Fungi. We showed that protozoa had Sec tRNA on which Sec was synthesized from Ser-tRNA by bovine and protozoa SecS. Some worms, such as Caenorhabditis elegans and Fasiola gigantica, also had Sec tRNA on which Sec was synthesized by bovine liver SecS or C. elegans enzymes. We showed recognition sites of mammalian Sec tRNA by SecS. The identity units of Sec tRNA are 9 bp aminoacyl- and 6 bp D-stems. This recognition is not the base-specific manner but the length-specific manner. From comparison of the phylogeny trees of Sec synthesizing system and translation system, we concluded that the evolution of Sec synthesizing system is older than that of the translation system.

  2. Oxygen and Biological Evolution.

    ERIC Educational Resources Information Center

    Baugh, Mark A.

    1990-01-01

    Discussed is the evolution of aerobic organisms from anaerobic organisms and the accompanying biochemistry that developed to motivate and enable this evolution. Uses of oxygen by aerobic organisms are described. (CW)

  3. The Evolution of Design

    ERIC Educational Resources Information Center

    Stebbins, G. Ledyard

    1973-01-01

    Describes the basic logic behind the modern view of evolution theory. Despite gaps in fossil records, evidence is indicative of the origin of life from nonliving molecules and evolution of higher forms of life from simpler forms. (PS)

  4. Perspective: reverse evolution.

    PubMed

    Teotónio, H; Rose, M R

    2001-04-01

    For some time, the reversibility of evolution was primarily discussed in terms of comparative patterns. Only recently has this problem been studied using experimental evolution over shorter evolutionary time frames. This has raised questions of definition, experimental procedure, and the hypotheses being tested. Experimental evolution has provided evidence for multiple population genetic mechanisms in reverse evolution, including pleiotropy and mutation accumulation. It has also pointed to genetic factors that might prevent reverse evolution, such as a lack of genetic variability, epistasis, and differential genotype-by-environment interactions. The main focus of this perspective is on laboratory studies and their relevance to the genetics of reverse evolution. We discuss reverse evolution experiments with Drosophila, bacterial, and viral populations. Field studies of the reverse evolution of melanism in the peppered moth are also reviewed.

  5. Mistakes and Molecular Evolution.

    ERIC Educational Resources Information Center

    Trevors, J. T.

    1998-01-01

    Examines the role mistakes play in the molecular evolution of bacteria. Discusses the interacting physical, chemical, and biological factors that cause changes in DNA and play a role in prokaryotic evolution. (DDR)

  6. Decameter Type III-Like Bursts

    NASA Astrophysics Data System (ADS)

    Melnik, V. N.; Konovalenko, A. A.; Rutkevych, B. P.; Rucker, H. O.; Dorovskyy, V. V.; Abranin, E. P.; Lecacheux, A.; Brazhenko, A. I.; Stanislavskyy, A. A.

    2007-12-01

    Starting from 1960s Type III-like bursts (Type III bursts with high drift rates) in a wide frequency range from 300 to 950MHz have been observed. These new bursts observed at certain frequency being compared to the usual Type III bursts at the same frequency show similar behaviour but feature frequency drift 2-6 times higher than the normal bursts. In this paper we report the first observations of Type III-like bursts in decameter range, carried out during summer campaigns 2002 - 2004 at UTR-2 radio telescope. The circular polarization of the bursts was measured by the radio telescope URAN-2 in 2004. The observed bursts are analyzed and compared with usual Type III bursts in the decameter range. From the analysis of over 1100 Type III-like bursts, their main parameters have been found. Characteristic feature of the observed bursts is similar to Type III-like bursts at other frequencies, i.e. measured drift rates (5-10 MHz/s) of this bursts are few times larger than that for usual Type III bursts, and their durations (1-2 s) are few times smaller than that for usual Type III bursts in this frequency band.

  7. Characterization of ribonuclease III from Brucella.

    PubMed

    Wu, Chang-Xian; Xu, Xian-Jin; Zheng, Ke; Liu, Fang; Yang, Xu-Dong; Chen, Chuang-Fu; Chen, Huan-Chun; Liu, Zheng-Fei

    2016-04-01

    Bacterial ribonuclease III (RNase III) is a highly conserved endonuclease, which plays pivotal roles in RNA maturation and decay pathways by cleaving double-stranded structure of RNAs. Here we cloned rncS gene from the genomic DNA of Brucella melitensis, and analyzed the cleavage properties of RNase III from Brucella. We identified Brucella-encoding small RNA (sRNA) by high-throughput sequencing and northern blot, and found that sRNA of Brucella and Homo miRNA precursor (pre-miRNA) can be bound and cleaved by B.melitensis ribonuclease III (Bm-RNase III). Cleavage activity of Bm-RNase III is bivalent metal cations- and alkaline buffer-dependent. We constructed several point mutations in Bm-RNase III, whose cleavage activity indicated that the 133th Glutamic acid residue was required for catalytic activity. Western blot revealed that Bm-RNase III was differently expressed in Brucella virulence strain 027 and vaccine strain M5-90. Collectively, our data suggest that Brucella RNase III can efficiently bind and cleave stem-loop structure of small RNA, and might participate in regulation of virulence in Brucella.

  8. Nonlinear enhancement of oxygen evolution in thylakoid membranes: modeling the effect of light intensity and beta-cyclodextrin concentration.

    PubMed

    Fragata, Mário; Dudekula, Subhan

    2005-08-04

    the experimental data for a broad range of I and C. Note that, for C = 0, eq iii reverts to the light-response curve of oxygen evolution in the absence of beta-CD. We conclude that eq iii is a good approximation of the combined effect of irradiance and beta-CD concentration, meaning that the model has a significant value for predicting the outcome of associated photochemical and biochemical reactions.

  9. Comparative adsorption of Eu(III) and Am(III) on TPD.

    PubMed

    Fan, Q H; Zhao, X L; Ma, X X; Yang, Y B; Wu, W S; Zheng, G D; Wang, D L

    2015-09-01

    Comparative adsorption behaviors of Eu(III) and Am(III) on thorium phosphate diphosphate (TPD), i.e., Th4(PO4)4P2O7, have been studied using a batch approach and surface complexation model (SCM) in this study. The results showed that Eu(III) and Am(III) adsorption increased to a large extent with the increase in TPD dose. Strong pH-dependence was observed in both Eu(III) and Am(III) adsorption processes, suggesting that inner-sphere complexes (ISCs) were possibly responsible for the adsorption of Eu(III) and Am(III). Meanwhile, the adsorption of Eu(III) and Am(III) decreased to a different extent with the increase in ion strength, which was possibly related to outer-sphere complexes and/or ion exchange. In the presence of fulvic acid (FA), the adsorption of Eu(III) and Am(III) showed high enhancement mainly due to the ternary surface complexes of TPD-FA-Eu(3+) and TPD-FA-Am(3+). The SCM showed that one ion exchange (≡S3Am/Eu) and two ISCs (≡(XO)2Am/EuNO3 and ≡(YO)2Am/EuNO3) seemed more reasonable to quantitatively describe the adsorption edges of both Eu(III) and Am(III). Our findings obviously showed that Eu(III) could be a good analogue to study actinide behaviors in practical terms. However, it should be kept in mind that there are still obvious differences between the characteristics of Eu(III) and Am(III) in some special cases, for instance, the complex ability with organic matter and adsorption affinity to a solid surface.

  10. HIV Evolution and Escape.

    PubMed Central

    Richman, Douglas D.; Little, Susan J.; Smith, Davey M.; Wrin, Terri; Petropoulos, Christos; Wong, Joseph K.

    2004-01-01

    Human immunodeficiency virus (HIV) exemplifies the principles of Darwinian evolution with a telescoped chronology. Because of its high mutation rate and remarkably high rates of replication, evolution can be appreciated over periods of days in contrast to the durations conceived of by Darwin. Certain selective pressures that drive the evolution of HIV include chemotherapy, anatomic compartmentalization and the immune response. Examples of these selective forces on HIV evolution are described. Images Fig. 5 PMID:17060974

  11. Inlet Geomorphology Evolution

    DTIC Science & Technology

    2015-04-01

    APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Inlet Geomorphology Evolution 5a. CONTRACT NUMBER 5b...Std Z39-18 Coastal Inlets Research Program Inlet Geomorphology Evolution The Inlet Geomorphology Evolution work unit of the CIRP evaluates

  12. Evolution & Diversity in Plants.

    ERIC Educational Resources Information Center

    Pearson, Lorentz C.

    1988-01-01

    Summarizes recent findings that help in understanding how evolution has brought about the diversity of plant life that presently exists. Discusses basic concepts of evolution, diversity and classification, the three-line hypothesis of plant evolution, the origin of fungi, and the geologic time table. Included are 31 references. (CW)

  13. Arguing for Evolution.

    ERIC Educational Resources Information Center

    Ayala, Francisco J.

    2000-01-01

    Discusses the Kansas State Board of Education's decision to remove references to evolution and cosmology from the state's education standards and assessment. Advocates the need to teach evolution in high schools for a meaningful biology education. Addresses the question whether the teaching of evolution poses a threat to Christianity or other…

  14. Improvement of thermostability and activity of Trichoderma reesei endo-xylanase Xyn III on insoluble substrates.

    PubMed

    Matsuzawa, Tomohiko; Kaneko, Satoshi; Yaoi, Katsuro

    2016-09-01

    Trichoderma reesei Xyn III, an endo-β-1,4-xylanase belonging to glycoside hydrolase family 10 (GH10), is vital for the saccharification of xylans in plant biomass. However, its enzymatic thermostability and hydrolytic activity on insoluble substrates are low. To overcome these difficulties, the thermostability of Xyn III was improved using random mutagenesis and directed evolution, and its hydrolytic activity on insoluble substrates was improved by creating a chimeric protein. In the screening of thermostable Xyn III mutants from a random mutagenesis library, we identified two amino acid residues, Gln286 and Asn340, which are important for the thermostability of Xyn III. The Xyn III Gln286Ala/Asn340Tyr mutant showed xylanase activity even after heat treatment at 60 °C for 30 min or 50 °C for 96 h, indicating a dramatic enhancement in thermostability. In addition, we found that the addition of a xylan-binding domain (XBD) to the C-terminal of Xyn III improved its hydrolytic activity on insoluble xylan.

  15. Influence of organic matters on AsIII oxidation by the microflora of polluted soils.

    PubMed

    Lescure, T; Moreau, J; Charles, C; Ben Ali Saanda, T; Thouin, H; Pillas, N; Bauda, P; Lamy, I; Battaglia-Brunet, F

    2016-06-01

    The global AsIII-oxidizing activity of microorganisms in eight surface soils from polluted sites was quantified with and without addition of organic substrates. The organic substances provided differed by their nature: either yeast extract, commonly used in microbiological culture media, or a synthetic mixture of defined organic matters (SMOM) presenting some common features with natural soil organic matter. Correlations were sought between soil characteristics and both the AsIII-oxidizing rate constants and their evolution in accordance with inputs of organic substrates. In the absence of added substrate, the global AsIII oxidation rate constant correlated positively with the concentration of intrinsic organic matter in the soil, suggesting that AsIII-oxidizing activity was limited by organic substrate availability in nutrient-poor soils. This limitation was, however, removed by 0.08 g/L of added organic carbon. In most conditions, the AsIII oxidation rate constant decreased as organic carbon input increased from 0.08 to 0.4 g/L. Incubations of polluted soils in aerobic conditions, amended or not with SMOM, resulted in short-term As mobilization in the presence of SMOM and active microorganisms. In contrast, microbial AsIII oxidation seemed to stabilize As when no organic substrate was added. Results suggest that microbial speciation of arsenic driven by nature and concentration of organic matter exerts a major influence on the fate of this toxic element in surface soils.

  16. Conditions for duality between fluxes and concentrations in biochemical networks.

    PubMed

    Fleming, Ronan M T; Vlassis, Nikos; Thiele, Ines; Saunders, Michael A

    2016-11-21

    Mathematical and computational modelling of biochemical networks is often done in terms of either the concentrations of molecular species or the fluxes of biochemical reactions. When is mathematical modelling from either perspective equivalent to the other? Mathematical duality translates concepts, theorems or mathematical structures into other concepts, theorems or structures, in a one-to-one manner. We present a novel stoichiometric condition that is necessary and sufficient for duality between unidirectional fluxes and concentrations. Our numerical experiments, with computational models derived from a range of genome-scale biochemical networks, suggest that this flux-concentration duality is a pervasive property of biochemical networks. We also provide a combinatorial characterisation that is sufficient to ensure flux-concentration duality.The condition prescribes that, for every two disjoint sets of molecular species, there is at least one reaction complex that involves species from only one of the two sets. When unidirectional fluxes and molecular species concentrations are dual vectors, this implies that the behaviour of the corresponding biochemical network can be described entirely in terms of either concentrations or unidirectional fluxes.

  17. Biochemical diagnosis in 3040 kidney stone formers in Argentina.

    PubMed

    Spivacow, Francisco Rodolfo; del Valle, Elisa Elena; Negri, Armando Luis; Fradinger, Erich; Abib, Anabella; Rey, Paula

    2015-08-01

    Nephrolithiasis is a frequent condition in urology that has an important recurrence and high impact in health economy. Knowing the biochemical abnormalities implicated in its pathogenesis is mandatory to establish therapeutic aims. Our objectives are to present the results in 3040 kidney stone formers in Argentina. All patients were selected after completing an ambulatory metabolic protocol with diagnostic purposes. There were 1717 men, (56.48%), with a mean age of 45±12 years, and 1323 women, (43.52%), mean age 44±12 years. 2781 patients had biochemical abnormalities, (91.49%), and were arbitrarily divided in two groups: those who had only one (single) biochemical abnormality (n=2156) and those who had associated abnormalities (n=625). No biochemical abnormalities were found in 259 patients (8.51%). The abnormalities present, single and associated, in order of frequency, were idiopathic hypercalciuria, (56.88%), hyperuricosuria (21.08%), unduly acidic urine (10.95%), hypocitraturia (10.55%), hypomagnesuria (7.9%), primary hyperparathyroidism (3.01%), hyperoxaluria (2.6%), and cystinuria (0.32%). We performed in 484 patient's stone composition and found calcium oxalate stones related to idiopathic hypercalciuria predominantly while uric acid stones to unduly acidic urine. In conclusion, the biochemical abnormalities described are similar to those found in a previous series of our own and to those reported in the literature. Its diagnosis is important to therapeutic purposes to avoid eventual recurrence.

  18. [Ribosomal RNA Evolution

    NASA Technical Reports Server (NTRS)

    1997-01-01

    It is generally believed that an RNA World existed at an early stage in the history of life. During this early period, RNA molecules are seen to be potentially involved in both catalysis and the storage of genetic information. Translation presents several interrelated themes of inquiry for exobiology. First, it is essential, for understanding the very origin of life, how peptides and eventually proteins might have come to be made on the early Earth in a template directed manner. Second, it is necessary to understand how a machinery of similar complexity to that found in the ribosomes of modern organisms came to exist by the time of the last common ancestor (as detected by 16S rRNA sequence studies). Third, the ribosomal RNAs themselves likely had a very early origin and studies of their history may be very informative about the nature of the RNA World. Moreover, studies of these RNAs will contribute to a better understanding of the potential roles of RNA in early evolution.During the past year we have ave conducted a comparative study of four completely sequenced bacterial genoames. We have focused initially on conservation of gene order. The second component of the project continues to build on the model system for studying the validity of variant 5S rRNA sequences in the vicinity of the modern Vibrio proteolyticus 5S rRNA that we established earlier. This system has made it possible to conduct a detailed and extensive analysis of a local portion of the sequence space. These core methods have been used to construct numerous mutants during the last several years. Although it has been a secondary focus, this work has continued over the last year such that we now have in excess of 125 V. proteolyticus derived constructs which have been made and characterized. We have also continued high resolution NMR work on RNA oligomers originally initiated by G. Kenneth Smith who was funded by a NASA Graduate Student Researcher's Fellowship Award until May of 1996. Mr. Smith

  19. Structural basis for activation, assembly and membrane binding of ESCRT-III Snf7 filaments.

    PubMed

    Tang, Shaogeng; Henne, W Mike; Borbat, Peter P; Buchkovich, Nicholas J; Freed, Jack H; Mao, Yuxin; Fromme, J Christopher; Emr, Scott D

    2015-12-15

    The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that catalyze multiple topologically similar membrane-remodeling processes. Although ESCRT-III subunits polymerize into spirals, how individual ESCRT-III subunits are activated and assembled together into a membrane-deforming filament remains unknown. Here, we determine X-ray crystal structures of the most abundant ESCRT-III subunit Snf7 in its active conformation. Using pulsed dipolar electron spin resonance spectroscopy (PDS), we show that Snf7 activation requires a prominent conformational rearrangement to expose protein-membrane and protein-protein interfaces. This promotes the assembly of Snf7 arrays with ~30 Å periodicity into a membrane-sculpting filament. Using a combination of biochemical and genetic approaches, both in vitro and in vivo, we demonstrate that mutations on these protein interfaces halt Snf7 assembly and block ESCRT function. The architecture of the activated and membrane-bound Snf7 polymer provides crucial insights into the spatially unique ESCRT-III-mediated membrane remodeling.

  20. Programmable RNA shredding by the type III-A CRISPR-Cas system of Streptococcus thermophilus.

    PubMed

    Tamulaitis, Gintautas; Kazlauskiene, Migle; Manakova, Elena; Venclovas, Česlovas; Nwokeoji, Alison O; Dickman, Mark J; Horvath, Philippe; Siksnys, Virginijus

    2014-11-20

    Immunity against viruses and plasmids provided by CRISPR-Cas systems relies on a ribonucleoprotein effector complex that triggers the degradation of invasive nucleic acids (NA). Effector complexes of type I (Cascade) and II (Cas9-dual RNA) target foreign DNA. Intriguingly, the genetic evidence suggests that the type III-A Csm complex targets DNA, whereas biochemical data show that the type III-B Cmr complex cleaves RNA. Here we aimed to investigate NA specificity and mechanism of CRISPR interference for the Streptococcus thermophilus Csm (III-A) complex (StCsm). When expressed in Escherichia coli, two complexes of different stoichiometry copurified with 40 and 72 nt crRNA species, respectively. Both complexes targeted RNA and generated multiple cuts at 6 nt intervals. The Csm3 protein, present in multiple copies in both Csm complexes, acts as endoribonuclease. In the heterologous E. coli host, StCsm restricts MS2 RNA phage in a Csm3 nuclease-dependent manner. Thus, our results demonstrate that the type III-A StCsm complex guided by crRNA targets RNA and not DNA.

  1. Structural basis for activation, assembly and membrane binding of ESCRT-III Snf7 filaments

    PubMed Central

    Tang, Shaogeng; Henne, W Mike; Borbat, Peter P; Buchkovich, Nicholas J; Freed, Jack H; Mao, Yuxin; Fromme, J Christopher; Emr, Scott D

    2015-01-01

    The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that catalyze multiple topologically similar membrane-remodeling processes. Although ESCRT-III subunits polymerize into spirals, how individual ESCRT-III subunits are activated and assembled together into a membrane-deforming filament remains unknown. Here, we determine X-ray crystal structures of the most abundant ESCRT-III subunit Snf7 in its active conformation. Using pulsed dipolar electron spin resonance spectroscopy (PDS), we show that Snf7 activation requires a prominent conformational rearrangement to expose protein-membrane and protein-protein interfaces. This promotes the assembly of Snf7 arrays with ~30 Å periodicity into a membrane-sculpting filament. Using a combination of biochemical and genetic approaches, both in vitro and in vivo, we demonstrate that mutations on these protein interfaces halt Snf7 assembly and block ESCRT function. The architecture of the activated and membrane-bound Snf7 polymer provides crucial insights into the spatially unique ESCRT-III-mediated membrane remodeling. DOI: http://dx.doi.org/10.7554/eLife.12548.001 PMID:26670543

  2. Mechanisms of Sb(III) Photooxidation by the Excitation of Organic Fe(III) Complexes.

    PubMed

    Kong, Linghao; He, Mengchang

    2016-07-05

    Organic Fe(III) complexes are widely distributed in the aqueous environment, which can efficiently generate free radicals under light illumination, playing a significant role in heavy metal speciation. However, the potential importance of the photooxidation of Sb(III) by organic Fe(III) complexes remains unclear. Therefore, the photooxidation mechanisms of Sb(III) were comprehensively investigated in Fe(III)-oxalate, Fe(III)-citrate and Fe(III)-fulvic acid (FA) solutions by kinetic measurements and modeling. Rapid photooxidation of Sb(III) was observed in an Fe(III)-oxalate solution over the pH range of 3 to 7. The addition of tert-butyl alcohol (TBA) as an ·OH scavenger quenched the Sb(III) oxidation, suggesting that ·OH is an important oxidant for Sb(III). However, the incomplete quenching of Sb(III) oxidation indicated the existence of other oxidants, presumably an Fe(IV) species in irradiated Fe(III)-oxalate solution. In acidic solutions, ·OH may be formed by the reaction of Fe(II)(C2O4) with H2O2, but a hypothetical Fe(IV) species may be generated by the reaction of Fe(II)(C2O4)2(2-) with H2O2 at higher pH. Kinetic modeling provides a quantitative explanation of the results. Evidence for the existence of ·OH and hypothetical Fe(IV) was also observed in an irradiated Fe(III)-citrate and Fe(III)-FA system. This study demonstrated an important pathway of Sb(III) oxidation in surface waters.

  3. Frontiers of stellar evolution

    NASA Technical Reports Server (NTRS)

    Lambert, David L. (Editor)

    1991-01-01

    The present conference discusses theoretical and observational views of star formation, spectroscopic constraints on the evolution of massive stars, very low mass stars and brown dwarfs, asteroseismology, globular clusters as tests of stellar evolution, observational tests of stellar evolution, and mass loss from cool evolved giant stars. Also discussed are white dwarfs and hot subdwarfs, neutron stars and black holes, supernovae from single stars, close binaries with evolved components, accretion disks in interacting binaries, supernovae in binary systems, stellar evolution and galactic chemical evolution, and interacting binaries containing compact components.

  4. Hematologic and plasma biochemical values of hyacinth macaws (Anodorhynchus hyacinthinus).

    PubMed

    Kolesnikovas, Cristiane K M; Niemeyer, Claudia; Teixeira, Rodrigo H F; Nunes, Adauto L V; Rameh-de-Albuquerque, Luciana C; Sant'Anna, Sávio S; Catão-Dias, José L

    2012-09-01

    The hyacinth macaw (Anodorhyncus hyacinthinus), considered the largest psittacine bird species in the world, is an endangered species, with a remaining population of approximately 6500 birds in the wild. To establish hematologic and plasma biochemical reference ranges and to verify differences related to sex, samples from 29 hyacinth macaws (14 males, 15 females) were obtained from birds apprehended from illegal wildlife trade and subsequently housed at the Sorocaba Zoo, Brazil. No significant differences in hematologic or plasma biochemical values were found between females and males. Compared with published reference values, differences were found in mean concentrations of total red blood cell count, corpuscular volume, corpuscular hemoglobin level, total white blood cell count, aspartate aminotransferase level, creatine kinase concentration, alkaline phosphatase concentration, and phosphorus level. Baseline hematologic and plasma biochemical ranges were established, which may be useful as reference values for clinicians working with this endangered species in captivity or rehabilitation centers.

  5. Hematologic and plasma biochemical values of Spix's macaws (Cyanopsitta spixii).

    PubMed

    Foldenauer, Ulrike; Borjal, Raffy Jim; Deb, Amrita; Arif, Abdi; Taha, Abid Sharif; Watson, Ryan William; Steinmetz, Hanspeter; Bürkle, Marcellus; Hammer, Sven

    2007-12-01

    The Spix's macaw (Cyanopsitta spixii) is considered the world's most endangered parrot, with the last wild bird disappearing in 2001 and only 74 birds in captivity. To establish hematologic and plasma biochemical reference ranges and to look for differences relative to sex, age, and season, we obtained blood samples from 46 captive Spix's macaws (23 male, 23 female) housed in aviaries at the Al Wabra Wildlife Preservation in the State of Qatar. No significant differences in hematologic or plasma biochemical values were found between females and males. Adult and juvenile birds differed in mean concentrations of glucose, total protein, amylase, cholesterol, and phosphorus; in percentages of heterophils and lymphocytes; and in the absolute lymphocyte count. Total protein, cholesterol, and phosphorus concentrations; hematocrit; and heterophil and lymphocyte counts differed significantly by season. Baseline hematologic and plasma biochemical ranges were established, which may be useful as reference values for clinicians working with this highly endangered species.

  6. Click Chemistry-Mediated Nanosensors for Biochemical Assays

    PubMed Central

    Chen, Yiping; Xianyu, Yunlei; Wu, Jing; Yin, Binfeng; Jiang, Xingyu

    2016-01-01

    Click chemistry combined with functional nanoparticles have drawn increasing attention in biochemical assays because they are promising in developing biosensors with effective signal transformation/amplification and straightforward signal readout for clinical diagnostic assays. In this review, we focus on the latest advances of biochemical assays based on Cu (I)-catalyzed 1, 3-dipolar cycloaddition of azides and alkynes (CuAAC)-mediated nanosensors, as well as the functionalization of nanoprobes based on click chemistry. Nanoprobes including gold nanoparticles, quantum dots, magnetic nanoparticles and carbon nanomaterials are covered. We discuss the advantages of click chemistry-mediated nanosensors for biochemical assays, and give perspectives on the development of click chemistry-mediated approaches for clinical diagnosis and other biomedical applications. PMID:27217831

  7. Click Chemistry-Mediated Nanosensors for Biochemical Assays.

    PubMed

    Chen, Yiping; Xianyu, Yunlei; Wu, Jing; Yin, Binfeng; Jiang, Xingyu

    2016-01-01

    Click chemistry combined with functional nanoparticles have drawn increasing attention in biochemical assays because they are promising in developing biosensors with effective signal transformation/amplification and straightforward signal readout for clinical diagnostic assays. In this review, we focus on the latest advances of biochemical assays based on Cu (I)-catalyzed 1, 3-dipolar cycloaddition of azides and alkynes (CuAAC)-mediated nanosensors, as well as the functionalization of nanoprobes based on click chemistry. Nanoprobes including gold nanoparticles, quantum dots, magnetic nanoparticles and carbon nanomaterials are covered. We discuss the advantages of click chemistry-mediated nanosensors for biochemical assays, and give perspectives on the development of click chemistry-mediated approaches for clinical diagnosis and other biomedical applications.

  8. National Coastal Condition Report III (2008)

    EPA Pesticide Factsheets

    The National Coastal Condition Report III (NCCR III) is the third in a series of environmental assessments of U.S. coastal waters and the Great Lakes. The report includes assessments of the nation’s estuaries in the contiguous 48 states and Puerto Rico.

  9. Synthesis, spectroscopic and antimicrobial studies of La(III), Ce(III), Sm(III) and Y(III) Metformin HCl chelates.

    PubMed

    Refat, Moamen S; Al-Azab, Fathi M; Al-Maydama, Hussein M A; Amin, Ragab R; Jamil, Yasmin M S; Kobeasy, Mohamed I

    2015-05-05

    Metal complexes of Metformin hydrochloride were prepared using La(III), Ce(III), Sm(III) and Y(III). The resulting complexes were discussed and synthesized to serve as potential insulin-mimetic. Some physical properties and analytical data of the four complexes were checked. The elemental analysis shows that La(III), Ce(III) Sm(III) and Y(III) formed complexes with Metformin in 1:3 (metal:MF) molar ratio. All the synthesized complexes are white and possess high melting points. These complexes are soluble in dimethylsulfoxide and dimethylformamide, partially soluble in hot methanol and insoluble in water and some other organic solvents. From the spectroscopic (infrared, UV-vis and florescence), effective magnetic moment and elemental analyses data, the formula structures are suggested. The results obtained suggested that Metformin reacted with metal ions as a bidentate ligand through its two imino groups. The molar conductance measurements proved that the Metformin complexes are slightly electrolytic in nature. The kinetic thermodynamic parameters such as: E(∗), ΔH(∗), ΔS(∗) and ΔG(∗) were estimated from the DTG curves. The antibacterial evaluations of the Metformin and their complexes were also performed against some gram positive, negative bacteria as well as fungi.

  10. JumpStart III Final Report.

    ERIC Educational Resources Information Center

    Cohen, Arthur M.; Brawer, Florence B.; Kozeracki, Carol A.

    This final report for the JumpStart III program presents a summary of the entrepreneurship training programs developed by each of the four JumpStart III partners selected in March 1997. Grants for the colleges totaled $354,546 over 2 years. The Jumpstart funding has been only a starting point for these and the other 12 Jumpstart partners in…

  11. Grant Administration Manual for Title III Coordinators.

    ERIC Educational Resources Information Center

    Mathis, Emily Duncan; Ashmore, Frances W.

    Guidelines for coordinators of programs under Title III of the Higher Education Act of 1965 are presented, based on a national survey of Title III program coordinators. The responsibilities of the coordinator and information on administering the Strengthening Developing Institutions Program (SDIP) grant are covered. The program can either be a…

  12. Preparation of III-V semiconductor nanocrystals

    DOEpatents

    Alivisatos, A. Paul; Olshavsky, Michael A.

    1996-01-01

    Nanometer-scale crystals of III-V semiconductors are disclosed, They are prepared by reacting a group III metal source with a group V anion source in a liquid phase at elevated temperature in the presence of a crystallite growth terminator such as pyridine or quinoline.

  13. Cyanoacrylate glue for type iii lad perforation.

    PubMed

    Trehan, V K; Nigam, Arima

    2008-01-01

    Coronary artery perforation especially type III is a rare and catastrophic complication of percutaneous coronary intervention. It mandates emergency open heart surgery if hemostasis is not achieved promptly. We report a case of type III left anterior descending artery (LAD) perforation which was managed successfully with cyanoacrylate glue.

  14. Genes, genetics, and Class III malocclusion.

    PubMed

    Xue, F; Wong, R W K; Rabie, A B M

    2010-05-01

    To present current views that are pertinent to the investigation of the genetic etiology of Class III malocclusion. Class III malocclusion is thought to be a polygenic disorder that results from an interaction between susceptibility genes and environmental factors. However, research on family pedigrees has indicated that Class III malocclusion might also be a monogenic dominant phenotype. Recent studies have reported that genes that encode specific growth factors or other signaling molecules are involved in condylar growth under mechanical strain. These genes, which include Indian hedgehog homolog (IHH), parathyroid-hormone like hormone (PTHLH), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF), and variations in their levels of expression play an important role in the etiology of Class III malocclusion. In addition, genome-wide scans have revealed chromosomal loci that are associated with Class III malocclusion. It is likely that chromosomal loci 1p36, 12q23, and 12q13 harbor genes that confer susceptibility to Class III malocclusion. In a case-control association study, we identified erythrocyte membrane protein band 4.1 (EPB41) to be a new positional candidate gene that might be involved in susceptibility to mandibular prognathism. Most of the earlier studies on the genetic etiology of Class III malocclusion have focused on the patterns of inheritance of this phenotype. Recent investigations have focused on understanding the genetic variables that affect Class III malocclusion and might provide new approaches to uncovering the genetic etiology of this phenotype.

  15. Preparation of III-V semiconductor nanocrystals

    DOEpatents

    Alivisatos, A.P.; Olshavsky, M.A.

    1996-04-09

    Nanometer-scale crystals of III-V semiconductors are disclosed. They are prepared by reacting a group III metal source with a group V anion source in a liquid phase at elevated temperature in the presence of a crystallite growth terminator such as pyridine or quinoline. 4 figs.

  16. Synthesis and in vitro microbial evaluation of La(III), Ce(III), Sm(III) and Y(III) metal complexes of vitamin B6 drug

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Al-Azab, Fathi M.; Al-Maydama, Hussein M. A.; Amin, Ragab R.; Jamil, Yasmin M. S.

    2014-06-01

    Metal complexes of pyridoxine mono hydrochloride (vitamin B6) are prepared using La(III), Ce(III), Sm(III) and Y(III). The resulting complexes are investigated. Some physical properties, conductivity, analytical data and the composition of the four pyridoxine complexes are discussed. The elemental analysis shows that the formed complexes of La(III), Ce(III), Sm(III) and Y(III) with pyridoxine are of 1:2 (metal:PN) molar ratio. All the synthesized complexes are brown in color and possess high melting points. These complexes are partially soluble in hot methanol, dimethylsulfoxide and dimethylformamide and insoluble in water and some other organic solvents. Elemental analysis data, spectroscopic (IR, UV-vis. and florescence), effective magnetic moment in Bohr magnetons and the proton NMR suggest the structures. However, definite particle size is determined by invoking the X-ray powder diffraction and scanning electron microscopy data. The results obtained suggested that pyridoxine reacted with metal ions as a bidentate ligand through its phenolate oxygen and the oxygen of the adjacent group at the 4‧-position. The molar conductance measurements proved that the pyridoxine complexes are electrolytic in nature. The kinetic and thermodynamic parameters such as: Ea, ΔH*, ΔS* and ΔG* were estimated from the DTG curves. The antibacterial evaluation of the pyridoxine and their complexes were also performed against some gram positive, negative bacteria as well as fungi.

  17. Synthesis, spectroscopic and antimicrobial studies of La(III), Ce(III), Sm(III) and Y(III) Metformin HCl chelates

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Al-Azab, Fathi M.; Al-Maydama, Hussein M. A.; Amin, Ragab R.; Jamil, Yasmin M. S.; Kobeasy, Mohamed I.

    2015-05-01

    Metal complexes of Metformin hydrochloride were prepared using La(III), Ce(III), Sm(III) and Y(III). The resulting complexes were discussed and synthesized to serve as potential insulin-mimetic. Some physical properties and analytical data of the four complexes were checked. The elemental analysis shows that La(III), Ce(III) Sm(III) and Y(III) formed complexes with Metformin in 1:3 (metal:MF) molar ratio. All the synthesized complexes are white and possess high melting points. These complexes are soluble in dimethylsulfoxide and dimethylformamide, partially soluble in hot methanol and insoluble in water and some other organic solvents. From the spectroscopic (infrared, UV-vis and florescence), effective magnetic moment and elemental analyses data, the formula structures are suggested. The results obtained suggested that Metformin reacted with metal ions as a bidentate ligand through its two imino groups. The molar conductance measurements proved that the Metformin complexes are slightly electrolytic in nature. The kinetic thermodynamic parameters such as: E∗, ΔH∗, ΔS∗ and ΔG∗ were estimated from the DTG curves. The antibacterial evaluations of the Metformin and their complexes were also performed against some gram positive, negative bacteria as well as fungi.

  18. Genetics Home Reference: mucolipidosis III gamma

    MedlinePlus

    ... time. People with mucolipidosis III gamma often have heart valve abnormalities and mild clouding of the clear covering ... III Gamma MedlinePlus Encyclopedia: Cloudy Cornea MedlinePlus Encyclopedia: Heart Valves General Information from MedlinePlus (5 links) Diagnostic Tests ...

  19. Evolution prediction from tomography

    NASA Astrophysics Data System (ADS)

    Dominy, Jason M.; Venuti, Lorenzo Campos; Shabani, Alireza; Lidar, Daniel A.

    2017-03-01

    Quantum process tomography provides a means of measuring the evolution operator for a system at a fixed measurement time t. The problem of using that tomographic snapshot to predict the evolution operator at other times is generally ill-posed since there are, in general, infinitely many distinct and compatible solutions. We describe the prediction, in some "maximal ignorance" sense, of the evolution of a quantum system based on knowledge only of the evolution operator for finitely many times 0<τ 1evolution at times away from the measurement times. Even if the original evolution is unitary, the predicted evolution is described by a non-unitary, completely positive map.

  20. Comparative biochemical and RAPD analysis in two varieties of rice (Oryza sativa) under arsenic stress by using various biomarkers.

    PubMed

    Ahmad, Mohd Anwar; Gaur, Rashmi; Gupta, Meetu

    2012-05-30

    Multiple biomarker systems have been frequently used to measure the genotoxic effects of environmental pollutants (including heavy metals) on living organisms. In this study, we used leaves of hydroponically grown 14 days old seedlings of rice (Oryza sativa) varieties (PB1 and IR64) treated with 50, 150 and 300 μM arsenite (As(III)) for 24 and 96 h duration. Reduction in seed germination, root-shoot length, chlorophyll and protein were observed with increasing As(III) concentration and duration in both varieties, being more in IR64. Increase/decrease of antioxidant enzymes and stress related parameters showed much changes at higher concentration for 24 and 96 h duration in both varieties. Eleven primers were found in RAPD analysis to produce polymorphic band pattern and produced a total of 51 (control), 79 (treated) and 42 (control) and 29 (treated) bands in PB1 and IR64 varieties, respectively. These results indicated that genomic template stability (GTS, changes in RAPD profile) was significantly affected at all tested As(III) concentration, when compared with other parameters. Differential response was observed in both varieties with PB1 being more tolerant. We concluded that DNA polymorphism detected by RAPD analysis in conjunction with other biochemical parameters could be a powerful eco-toxicological tool in bio-monitoring arsenic pollution.

  1. Cyanido Antimonate(III) and Bismuthate(III) Anions.

    PubMed

    Arlt, Sören; Harloff, Jörg; Schulz, Axel; Stoffers, Alrik; Villinger, Alexander

    2016-12-05

    The reaction of in situ generated E(CN)3 (E = Sb, Bi) with different amounts of [Ph4P]CN and [PPN]CN ([PPN](+) = [Ph3P-N-PPh3](+)) was studied, affording salts bearing the novel ions [E(CN)5](2-), [Bi2(CN)11](5-), and [Bi(CN)6](3-). The valence lone pair of electrons on the central atom of antimony and bismuth(III) compounds can be either sterically active in an unsymmetric fashion (three shorter bonds + x longer bonds) or symmetric (with rather long averaged bonds). In the presence of weakly coordinating cations (e.g., [Ph4P](+) and [PPN](+)), the solid-state structures of salts with [E(CN)5](2-) anions contain well-separated cations and monomeric anions, which display a sterically active lone pair and a monomeric square-based pyramidal (pseudo-octahedral) structure. The [Bi(CN)5·MeCN](2-) acetonitrile adduct ion exhibits a strongly distorted octahedral structure, which is better understood as a [5 + 1] coordination. The intriguing [Ph4P]6[Bi2(CN)11]CN salt consists of separated cations and anions as well as well-separated [Bi2(CN)11](5-) and CN(-) ions. The structure of the molecular [Bi2(CN)11](5-) ion can be described as two square-based-pyramidal [Bi(CN)5](2-) fragments connected by a disordered bridging CN(-) ion, thereby leading to a distorted-octahedral environment around the two Bi centers. Here the steric effect of the lone pair is much less pronounced but still present.

  2. Design III with Marker Loci

    PubMed Central

    Cockerham, C. C.; Zeng, Z. B.

    1996-01-01

    Design III is an experimental design originally proposed by R. E. COMSTOCK and H. F. ROBINSON for estimating genetic variances and the average degree of dominance for quantitative trait loci (QTL) and has recently been extended for mapping QTL. In this paper, we first extend COMSTOCK and ROBINSON's analysis of variance to include linkage, two-locus epistasis and the use of F(3) parents. Then we develop the theory and statistical analysis of orthogonal contrasts and contrast X environment interaction for a single marker locus to characterize the effects of QTL. The methods are applied to the maize data of C. W. STUBER. The analyses strongly suggest that there are multiple linked QTL in many chromosomes for several traits examined. QTL effects are largely environment-independent for grain yield, ear height, plant height and ear leaf area and largely environment dependent for days to tassel, grain moisture and ear number. There is significant QTL epistasis. The results are generally in favor of the hypothesis of dominance of favorable genes to explain the observed heterosis in grain yield and other traits, although epistasis could also play an important role and overdominance at individual QTL level can not be ruled out. PMID:8807314

  3. Mark III results from SPEAR

    SciTech Connect

    Toki, W.

    1983-11-01

    First results from the MARK III detector at SPEAR are presented based on 2.7 million J/psi decays. The eta/sub c/ is observed in three modes, J/psi ..-->.. ..gamma..eta/sub c/, (eta/sub c/ ..-->.. rho anti rho, eta..pi../sup +/..pi../sup -/, and phi phi). Using the phi phi mode, the eta/sub c/ spin-parity is determined to be 0/sup -/. The known radiative J/psi decays J/psi ..-->.. ..gamma..f(f ..-->.. ..pi../sup +/..pi../sup -/), ..gamma..eta'(eta' ..-->.. ..gamma..rho/sup 0/, eta..pi../sup +/..pi../sup -/), ..gamma..f'(f' ..-->.. kappa/sup +/kappa/sup -/), ..gamma..theta(theta ..-->.. kappa anti kappa), and ..gamma..iota(iota ..-->.. ..pi..kappa anti kappa) are observed and their branching ratios found to be in agreement with previous measurements. In the J/psi ..-->.. ..gamma..kappa/sup +/kappa/sup -/ mode a new state is observed at 2.22 GeV and in the J/psi ..-->.. ..gamma gamma..rho/sup 0/ and ..gamma..eta..pi../sup +/..pi../sup -/ modes evidence for new structures near 1.4 GeV is presented. 29 references.

  4. III-V arsenide-nitride semiconductor

    NASA Technical Reports Server (NTRS)

    Major, Jo S. (Inventor); Welch, David F. (Inventor); Scifres, Donald R. (Inventor)

    2000-01-01

    III-V arsenide-nitride semiconductor are disclosed. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V materials varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V material can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.

  5. Radiation Dose Escalation in Stage III Non-Small-Cell Lung Cancer

    PubMed Central

    Terakedis, Breanne; Sause, William

    2011-01-01

    For patients with stage III non-small-cell lung cancer with unresectable or inoperable tumors, definitive chemoradiotherapy is often utilized. Historically, local control and overall survival rates have been poor. In an effort to improve local control, new chemotherapeutic agents in combination with higher doses of radiotherapy have been investigated. Early dose escalation trials date back to the 1980s, and the feasibility and efficacy of dose escalation for patients with inoperable stage III lung cancer continue to be topics of investigation. Herein, we review the evolution of chemotherapy as it relates to treatment of unresectable stage III lung cancer, and we outline the early and the more recent dose escalation studies. While dose escalation appears to provide a modest benefit in terms of preventing local failure and improving overall survival, advances in diagnostic imaging and radiotherapy treatment have possibly resulted in selection of a more favorable patient population. These variables make statements regarding the benefit of dose escalation challenging. PMID:22645713

  6. Overview of the DOE/SERI Biochemical Conversion Program

    SciTech Connect

    Wright, J D

    1986-09-01

    The Solar Energy Research Institute manages a program of research and development on the biochemical conversion of renewable lignocellulosic materials to liquid fuels for the Department of Energy's Biofuels and Municipal Waste Technology Division. The Biochemical Conversion Program is mission oriented so effort is concentrated on technologies which appear to have the greatest potential for being adopted by the private sector to economically convert lignocellulosic materials into high value liquid transportation fuels such as ethanol. The program is structured to supply the technology for such fuels to compete economically first as an octane booster or fuel additive, and, with additional improvements, as a neat fuel. 18 refs., 3 figs., 1 tab.

  7. [Biochemical differentiation of proteus strains from various clinical materials].

    PubMed

    Józefowicz-Piatkowska, H; Woch, G

    1993-01-01

    The material consisted of 729 strain of Proteus isolated from clinical samples in three microbiological laboratories of city of Lódź region. Our of these strains, 466 were Proteus mirabilis, and remaining represented: P. penneri-13 strains, P. vulgaris (II biogroup)-56 and 54 strains which were not classifiable on the basis of biochemical properties and scheme elaborated by Hickman et al. for biogroups of P. vulgaris. The authors indicate feasibility of differentiation of P. vulgaris basing on biochemical tests as a supplementary method to other tests of intracellular differentiation of Proteus.

  8. Clinical and Biochemical Markers of Cardiovascular Structure and Function in Women With the Metabolic Syndrome.

    PubMed

    Velarde, Gladys P; Sherazi, Saadia; Kraemer, Dale F; Bravo-Jaimes, Katia; Butterfield, Ryan; Amico, Tonja; Steinmetz, Sherry D; Guzman, Maricela; Martin, Dale; Dodani, Sunita; Smith, Brian H

    2015-12-01

    The pathobiological impact of individual components of the metabolic syndrome (MS) on cardiac structural and functional parameters in women with isolated MS is not known. The objectives of this study were (1) to compare biochemical (prothrombotic, lipogenic, and inflammatory) and imaging (carotid intima-media thickening and basic cardiac structural measurements) markers in women with and without MS and (2) to examine if any of these markers associated or predicted cardiac structural differences between the 2 groups. This cross-sectional pilot study included 88 women with MS and 35 women without it. MS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Patients with diagnosis of diabetes were excluded. Compared with healthy subjects, women with MS had higher levels of intercellular adhesion molecule, myeloperoxidase, C-reactive protein, plasminogen activator inhibitor-1, leptin, apolipoprotein-B, and lower levels of apolipoprotein-A1 (p <0.001 for all). They also had higher mean ventricular septum, posterior wall thickness, left ventricular (LV) mass, carotid intima-media thickness (p <0.001 for all), and left atrial diameter (p = 0.015). In multivariable regression models, waist circumference and systolic blood pressure (BP) were significant predictors of: ventricular septum (p = 0.005 and p = 0.001, respectively), posterior wall thickness (p = 0.008 and p = 0.040, respectively), and LV mass (p <0.001 and p = 0.013, respectively). Significant predictors for carotid intima-media thickness were systolic BP, glucose, and leptin (p <0.0001, p = 0.034, and p = 0.002, respectively). In conclusion, there are significant clinical, biochemical, and cardiovascular structural differences in women with isolated MS compared with those without. Waist circumference and systolic BP had the strongest association with cardiac structural differences in this group of women.

  9. To the understanding of the formation of the droplet-epitaxial III-V based nanostructures

    SciTech Connect

    Nemcsics, Ákos

    2014-05-15

    In this work, we discuss the evolution of the self-assembling III-V based nanostructures. These nano-structures were prepared by droplet epitaxial technique. The different nanostructures such as quantum dot, quantum ring, double quantum ring, or nanohole form similarly from an initial Ga droplet but under different substrate temperature and various arsenic pressures. Started from few atomic courses, we give here a qualitative description of the key processes for all of the aforementioned nanostructures.

  10. Type III secretion systems: the bacterial flagellum and the injectisome

    PubMed Central

    Diepold, Andreas; Armitage, Judith P.

    2015-01-01

    The flagellum and the injectisome are two of the most complex and fascinating bacterial nanomachines. At their core, they share a type III secretion system (T3SS), a transmembrane export complex that forms the extracellular appendages, the flagellar filament and the injectisome needle. Recent advances, combining structural biology, cryo-electron tomography, molecular genetics, in vivo imaging, bioinformatics and biophysics, have greatly increased our understanding of the T3SS, especially the structure of its transmembrane and cytosolic components, the transcriptional, post-transcriptional and functional regulation and the remarkable adaptivity of the system. This review aims to integrate these new findings into our current knowledge of the evolution, function, regulation and dynamics of the T3SS, and to highlight commonalities and differences between the two systems, as well as their potential applications. PMID:26370933

  11. Chemical Cartography with SDSS-III APOGEE: DR12 Results

    NASA Astrophysics Data System (ADS)

    Hayden, Michael R.; Holtzman, Jon A.; Bovy, Jo; Majewski, Steven R.; Nidever, David L.; Zasowski, Gail; Schiavon, Ricardo P.; Frinchaboy, Peter M.; Hearty, Fred; Allende-Prieto, Carlos; García Pérez, Ana; Robin, Annie; Cunha, Katia M. L.; Beers, Timothy C.; Apogee Team

    2015-01-01

    The SDSS-III Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectrograph provides an unprecedented view of the Milky Way disk, due in part to its ability to observe in the infrared, where the effects of extinction are significantly reduced compared to optical surveys. We present updated results on mean metallicity and chemical abundance gradients using the full three years of APOGEE1 observations and new results of the metallicity distribution function (MDF) and the [α/Fe] vs. [Fe/H] plane at different locations in the Milky Way disk. Our sample comprises nearly high signal-to-noise observations of nearly 100,000 red giant stars taken from SDSS DR12. These observations span the entire Milky Way visible from the northern hemisphere, ranging from the bulge to the edge of the disk (0

  12. Action of Brazilian propolis on hematological and serum biochemical parameters of Blue-fronted Amazons (Amazona aestiva, Linnaeus, 1758) in captivity.

    PubMed

    Silva, Cínthia R B; Putarov, Thaila C; Fruhvald, Erika; Destro, Flavia C; Marques Filho, Wolff C; Thomazini, Camila M; Barbosa, Tatiana S; Orsi, Ricardo O; Siqueira, Edson R

    2014-07-01

    The present study aimed to evaluate the effect of propolis use on hematological and serum biochemical parameters in Blue-fronted Amazons (Amazona aestiva). For this, 12 adult birds were distributed randomly into individual cages, divided into treatments with different propolis levels (A = 0.0%; B = 0.5%; and C = 1.0%), in 3 distinct phases (I, II, and III), with 15-d duration for phases I and III and 30 d for phase II, totaling 60 d. In phases I and III, all birds received treatment A ration, and in phase II received A, B, or C (4 birds per treatment). At the end of each phase, blood was collected for biochemical and hematological evaluations. The variables were analyzed by ANOVA (P < 0.05). Results suggest that 0.5% propolis reduced lactate dehydrogenase levels, whereas treatment B augmented hemoglobin concentrations and eosinophil count. It is concluded that 0.5% propolis improves levels of lactate dehydrogenase, hemoglobin, and eosinophils.

  13. Diverse evolutionary mechanisms shape the type III effector virulence factor repertoire in the plant pathogen Pseudomonas syringae.

    PubMed Central

    Rohmer, Laurence; Guttman, David S; Dangl, Jeffery L

    2004-01-01

    Many gram-negative pathogenic bacteria directly translocate effector proteins into eukaryotic host cells via type III delivery systems. Type III effector proteins are determinants of virulence on susceptible plant hosts; they are also the proteins that trigger specific disease resistance in resistant plant hosts. Evolution of type III effectors is dominated by competing forces: the likely requirement for conservation of virulence function, the avoidance of host defenses, and possible adaptation to new hosts. To understand the evolutionary history of type III effectors in Pseudomonas syringae, we searched for homologs to 44 known or candidate P. syringae type III effectors and two effector chaperones. We examined 24 gene families for distribution among bacterial species, amino acid sequence diversity, and features indicative of horizontal transfer. We assessed the role of diversifying and purifying selection in the evolution of these gene families. While some P. syringae type III effectors were acquired recently, others have evolved predominantly by descent. The majority of codons in most of these genes were subjected to purifying selection, suggesting selective pressure to maintain presumed virulence function. However, members of 7 families had domains subject to diversifying selection. PMID:15280247

  14. Separation studies of As(III), Sb(III) and Bi(III) by reversed-phase paper chromatographic technique

    SciTech Connect

    Raman, B.; Shinde, V.M.

    1987-07-01

    Reversed-phase paper chromatographic separations of As(III), Sb(III) and Bi(III) have been carried out on Whatman No 1 filter paper impregnated with triphenylphosphine oxide as stationary phase and using organic complexing agents such as sodium acetate, sodium succinate and sodium malonate solutions as active mobile phases. Results for the separation of binary and ternary mixtures are reported and the method has been successfully applied to the separation and detection of these elements present in real samples and at ppm level concentration.

  15. Lanthanide(III) and Yttrium(III) Complexes of Benzimidazole-2-Acetic Acid: Synthesis, Characterisation and Effect of La(III) Complex on Germination of Wheat

    PubMed Central

    Gudasi, Kalagouda B.; Shenoy, Rashmi V.; Vadavi, Ramesh S.; Patil, Manjula S.; Patil, Siddappa A.; Hanchinal, Rayappa R.; Desai, Srinivas A.; Lohithaswa, H.

    2006-01-01

    The synthesis and characterisation of lanthanide(III) and yttrium(III) nitrate complexes of benzimidazole-2-acetic acid (HBIA) are reported. The complexes have been characterised by elemental analysis, molar conductance, magnetic studies, IR, 1H NMR, UV-visible, EPR, and TG/DTA studies. They have the stoichiometry [Ln3(BIA)2(NO3)7(H2O)4] · 3H2O where Ln=La(III), Pr(III), Nd(II), Sm(III), Eu(III), Gd(III), Tb(III), Dy(III), and Y(III). The effect of La(III) complex on germination, coleoptile, and root length of two local varieties of wheat DWR-195 and GW-349 for different treatment periods has been investigated. The complex was found to exhibit enhanced activity, compared to HBIA or metal salt alone at lower treatment periods. PMID:17497017

  16. Evolutionary transitions during RNA virus experimental evolution.

    PubMed

    Elena, Santiago F

    2016-08-19

    In their search to understand the evolution of biological complexity, John Maynard Smith and Eörs Szathmáry put forward the notion of major evolutionary transitions as those in which elementary units get together to generate something new, larger and more complex. The origins of chromosomes, eukaryotic cells, multicellular organisms, colonies and, more recently, language and technological societies are examples that clearly illustrate this notion. However, a transition may be considered as anecdotal or as major depending on the specific level of biological organization under study. In this contribution, I will argue that transitions may also be occurring at a much smaller scale of biological organization: the viral world. Not only that, but also that we can observe in real time how these major transitions take place during experimental evolution. I will review the outcome of recent evolution experiments with viruses that illustrate four major evolutionary transitions: (i) the origin of a new virus that infects an otherwise inaccessible host and completely changes the way it interacts with the host regulatory and metabolic networks, (ii) the incorporation and loss of genes, (iii) the origin of segmented genomes from a non-segmented one, and (iv) the evolution of cooperative behaviour and cheating between different viruses or strains during co-infection of the same host.This article is part of the themed issue 'The major synthetic evolutionary transitions'.

  17. Cooperation, clumping and the evolution of multicellularity.

    PubMed

    Biernaskie, Jay M; West, Stuart A

    2015-08-22

    The evolution of multicellular organisms represents one of the major evolutionary transitions in the history of life. A potential advantage of forming multicellular clumps is that it provides an efficiency benefit to pre-existing cooperation, such as the production of extracellular 'public goods'. However, this is complicated by the fact that cooperation could jointly evolve with clumping, and clumping could have multiple consequences for the evolution of cooperation. We model the evolution of clumping and a cooperative public good, showing that (i) when considered separately, both clumping and public goods production gradually increase with increasing genetic relatedness; (ii) in contrast, when the traits evolve jointly, a small increase in relatedness can lead to a major shift in evolutionary outcome—from a non-clumping state with low public goods production to a cooperative clumping state with high values of both traits; (iii) high relatedness makes it easier to get to the cooperative clumping state and (iv) clumping can be inhibited when it increases the number of cells that the benefits of cooperation must be shared with, but promoted when it increases relatedness between those cells. Overall, our results suggest that public goods sharing can facilitate the formation of well-integrated cooperative clumps as a first step in the evolution of multicellularity.

  18. Neptunium(III) application in extraction chromatography.

    PubMed

    Guérin, Nicolas; Nadeau, Kenny; Larivière, Dominic

    2011-12-15

    This paper describes a novel strategy for actinide separation by extraction chromatography with Np(III) valence adjustment. Neptunium(IV) was reduced to Np(III) using Cr(II) and then selectively separated from uranium (IV) on a TEVA resin. After elution, Np(III) was retained on a DGA resin in order to remove any detrimental chromium impurities. Neptunium(III) formation was demonstrated by the complete and selective elution of Np from TEVA resin (99 ± 7%) in less than 12 mL of 9M HCl from U(IV) (0.7 ± 0.7%). It was determined by UV-visible and kinetic studies that Cr(II) was the only species responsible for the elution of Np(IV) as Np(III) and that the Cr(II) solution could be prepared from 2 to 30 min before its use without the need of complex degassing systems to prevent the oxidation of Np(III) by oxygen. The methodology proposed here with TEVA/DGA resins provides removal of Cr(III) impurities produced at high decontamination factors (2.8 × 10(3) and 7.3 × 10(4) respectively).

  19. Timely management of developing class III malocclusion.

    PubMed

    Yelampalli, M R; Rachala, M R

    2012-01-01

    Timing of orthodontic treatment, especially for children with developing class III malocclusions, has always been somewhat controversial, and definitive treatment tends to be delayed for severe class III cases. Developing class III patients with moderate to severe anterior crossbite and deep bite may need early intervention in some selected cases. Class III malocclusion may develop in children as a result of an inherent growth abnormality, i.e. true class III malocclusion, or as a result of premature occlusal contacts causing forward functional shift of the mandible, which is known as pseudo class III malocclusion. These cases, if not treated at the initial stage of development, interfere with normal growth of the jaw bases and may result in severe facial deformities. The treatment should be carried out as early as possible for permitting normal growth of the skeletal bases. This paper deals with the selection of an appropriate appliance from the various current options available for early intervention in developing class III malocclusion through two case reports.

  20. Chemical and biochemical thermodynamics: Is it time for a reunification?

    PubMed

    Iotti, Stefano; Raff, Lionel; Sabatini, Antonio

    2017-02-01

    The thermodynamics of chemical reactions in which all species are explicitly considered with atoms and charge balanced is compared with the transformed thermodynamics generally used to treat biochemical reactions where atoms and charges are not balanced. The transformed thermodynamic quantities suggested by Alberty are obtained by execution of Legendre transformation of the usual thermodynamic potentials. The present analysis demonstrates that the transformed values for ΔrG'(0) and ΔrH'(0)can be obtained directly without performing Legendre transformations by simply writing the chemical reactions with all the pseudoisomers explicitly included and charges balanced. The appropriate procedures for computing the stoichiometric coefficients for the pseudoisomers are fully explained by means of an example calculation for the biochemical ATP hydrolysis reaction. It is concluded that the analysis has reunited the "two separate worlds" of conventional thermodynamics and transformed thermodynamics. In addition, it is also shown that the value of the conditional Gibbs energy of reaction, ΔrG', for a biochemical reaction is the same of the value of ΔrG for any chemical reaction involving pseudoisomers of the biochemical reagents.

  1. Biochemical and physiological consequences of the Apollo flight diet.

    NASA Technical Reports Server (NTRS)

    Hander, E. W.; Leach, C. S.; Fischer, C. L.; Rummel, J.; Rambaut, P.; Johnson, P. C.

    1971-01-01

    Six male subjects subsisting on a typical Apollo flight diet for five consecutive days were evaluated for changes in biochemical and physiological status. Laboratory examinations failed to demonstrate any significant changes of the kind previously attributed to weightlessness, such as in serum electrolytes, endocrine values, body fluid, or hematologic parameters.

  2. MATLAB-Based Teaching Modules in Biochemical Engineering

    ERIC Educational Resources Information Center

    Lee, Kilho; Comolli, Noelle K.; Kelly, William J.; Huang, Zuyi

    2015-01-01

    Mathematical models play an important role in biochemical engineering. For example, the models developed in the field of systems biology have been used to identify drug targets to treat pathogens such as Pseudomonas aeruginosa in biofilms. In addition, competitive binding models for chromatography processes have been developed to predict expanded…

  3. Biochemical markers of spontaneous preterm birth in asymptomatic women.

    PubMed

    Chan, Ronna L

    2014-01-01

    Preterm birth is a delivery that occurs at less than 37 completed weeks of gestation and it is associated with perinatal morbidity and mortality. Spontaneous preterm birth accounts for up to 75% of all preterm births. A number of maternal or fetal characteristics have been associated with preterm birth, but the use of individual or group biochemical markers have advanced some of the understanding on the mechanisms leading to spontaneous preterm birth. This paper provides a summary on the current literature on the use of biochemical markers in predicting spontaneous preterm birth in asymptomatic women. Evidence from the literature suggests fetal fibronectin, cervical interleukin-6, and α-fetoprotein as promising biochemical markers in predicting spontaneous preterm birth in asymptomatic women. The role of gene-gene and gene-environment interactions, as well as epigenetics, has the potential to further elucidate and improve understanding of the underlying mechanisms or pathways of spontaneous preterm birth. Refinement in study design and methodology is needed in future research for the development and validation of individual or group biochemical marker(s) for use independently or in conjunction with other potential risk factors such as genetic variants and environmental and behavioral factors in predicting spontaneous preterm birth across diverse populations.

  4. Solving the differential biochemical Jacobian from metabolomics covariance data.

    PubMed

    Nägele, Thomas; Mair, Andrea; Sun, Xiaoliang; Fragner, Lena; Teige, Markus; Weckwerth, Wolfram

    2014-01-01

    High-throughput molecular analysis has become an integral part in organismal systems biology. In contrast, due to a missing systematic linkage of the data with functional and predictive theoretical models of the underlying metabolic network the understanding of the resulting complex data sets is lacking far behind. Here, we present a biomathematical method addressing this problem by using metabolomics data for the inverse calculation of a biochemical Jacobian matrix, thereby linking computer-based genome-scale metabolic reconstruction and in vivo metabolic dynamics. The incongruity of metabolome coverage by typical metabolite profiling approaches and genome-scale metabolic reconstruction was solved by the design of superpathways to define a metabolic interaction matrix. A differential biochemical Jacobian was calculated using an approach which links this metabolic interaction matrix and the covariance of metabolomics data satisfying a Lyapunov equation. The predictions of the differential Jacobian from real metabolomic data were found to be correct by testing the corresponding enzymatic activities. Moreover it is demonstrated that the predictions of the biochemical Jacobian matrix allow for the design of parameter optimization strategies for ODE-based kinetic models of the system. The presented concept combines dynamic modelling strategies with large-scale steady state profiling approaches without the explicit knowledge of individual kinetic parameters. In summary, the presented strategy allows for the identification of regulatory key processes in the biochemical network directly from metabolomics data and is a fundamental achievement for the functional interpretation of metabolomics data.

  5. Study on color difference estimation method of medicine biochemical analysis

    NASA Astrophysics Data System (ADS)

    Wang, Chunhong; Zhou, Yue; Zhao, Hongxia; Sun, Jiashi; Zhou, Fengkun

    2006-01-01

    The biochemical analysis in medicine is an important inspection and diagnosis method in hospital clinic. The biochemical analysis of urine is one important item. The Urine test paper shows corresponding color with different detection project or different illness degree. The color difference between the standard threshold and the test paper color of urine can be used to judge the illness degree, so that further analysis and diagnosis to urine is gotten. The color is a three-dimensional physical variable concerning psychology, while reflectance is one-dimensional variable; therefore, the estimation method of color difference in urine test can have better precision and facility than the conventional test method with one-dimensional reflectance, it can make an accurate diagnose. The digital camera is easy to take an image of urine test paper and is used to carry out the urine biochemical analysis conveniently. On the experiment, the color image of urine test paper is taken by popular color digital camera and saved in the computer which installs a simple color space conversion (RGB -> XYZ -> L *a *b *)and the calculation software. Test sample is graded according to intelligent detection of quantitative color. The images taken every time were saved in computer, and the whole illness process will be monitored. This method can also use in other medicine biochemical analyses that have relation with color. Experiment result shows that this test method is quick and accurate; it can be used in hospital, calibrating organization and family, so its application prospect is extensive.

  6. The use of biochemical methods in extraterrestrial life detection

    NASA Astrophysics Data System (ADS)

    McDonald, Gene

    2006-08-01

    Instrument development for in situ extraterrestrial life detection focuses primarily on the ability to distinguish between biological and non-biological material, mostly through chemical analysis for potential biosignatures (e.g., biogenic minerals, enantiomeric excesses). In constrast, biochemical analysis techniques commonly applied to Earth life focus primarily on the exploration of cellular and molecular processes, not on the classification of a given system as biological or non-biological. This focus has developed because of the relatively large functional gap between life and non-life on Earth today. Life on Earth is very diverse from an environmental and physiological point of view, but is highly conserved from a molecular point of view. Biochemical analysis techniques take advantage of this similarity of all terrestrial life at the molecular level, particularly through the use of biologically-derived reagents (e.g., DNA polymerases, antibodies), to enable analytical methods with enormous sensitivity and selectivity. These capabilities encourage consideration of such reagents and methods for use in extraterrestrial life detection instruments. The utility of this approach depends in large part on the (unknown at this time) degree of molecular compositional differences between extraterrestrial and terrestrial life. The greater these differences, the less useful laboratory biochemical techniques will be without significant modification. Biochemistry and molecular biology methods may need to be "de-focused" in order to produce instruments capable of unambiguously detecting a sufficiently wide range of extraterrestrial biochemical systems. Modern biotechnology tools may make that possible in some cases.

  7. Solving the Differential Biochemical Jacobian from Metabolomics Covariance Data

    PubMed Central

    Nägele, Thomas; Mair, Andrea; Sun, Xiaoliang; Fragner, Lena; Teige, Markus; Weckwerth, Wolfram

    2014-01-01

    High-throughput molecular analysis has become an integral part in organismal systems biology. In contrast, due to a missing systematic linkage of the data with functional and predictive theoretical models of the underlying metabolic network the understanding of the resulting complex data sets is lacking far behind. Here, we present a biomathematical method addressing this problem by using metabolomics data for the inverse calculation of a biochemical Jacobian matrix, thereby linking computer-based genome-scale metabolic reconstruction and in vivo metabolic dynamics. The incongruity of metabolome coverage by typical metabolite profiling approaches and genome-scale metabolic reconstruction was solved by the design of superpathways to define a metabolic interaction matrix. A differential biochemical Jacobian was calculated using an approach which links this metabolic interaction matrix and the covariance of metabolomics data satisfying a Lyapunov equation. The predictions of the differential Jacobian from real metabolomic data were found to be correct by testing the corresponding enzymatic activities. Moreover it is demonstrated that the predictions of the biochemical Jacobian matrix allow for the design of parameter optimization strategies for ODE-based kinetic models of the system. The presented concept combines dynamic modelling strategies with large-scale steady state profiling approaches without the explicit knowledge of individual kinetic parameters. In summary, the presented strategy allows for the identification of regulatory key processes in the biochemical network directly from metabolomics data and is a fundamental achievement for the functional interpretation of metabolomics data. PMID:24695071

  8. Metabolic decompensation in methylmalonic aciduria: which biochemical parameters are discriminative?

    PubMed

    Zwickler, Tamaris; Haege, Gisela; Riderer, Alina; Hörster, Friederike; Hoffmann, Georg F; Burgard, Peter; Kölker, Stefan

    2012-09-01

    Recurrent, life-threatening metabolic decompensations often occur in patients with methylmalonic aciduria (MMAuria). Our study evaluated (impending) metabolic decompensations in these patients aiming to identify the most frequent and reliable clinical and biochemical abnormalities that could be helpful for decision-making on when to start an emergency treatment. Seventy-six unscheduled and 179 regular visits of 10 patients with confirmed MMAuria continuously followed by our metabolic centre between 1975 and 2009 were analysed. The most frequent symptom of an impending acute metabolic decompensation was vomiting (90% of episodes), whereas symptoms of intercurrent infectious disease (29%) or other symptoms (such as food refusal and impaired consciousness) were found less often. Thirty-five biochemical parameters were included in the analysis. Among them, pathological changes of acid-base balance reflecting metabolic acidosis with partial respiratory compensation (decreased pH, pCO(2), standard bicarbonate, and base excess) and elevated ammonia were the most reliable biochemical parameters for the identification of a metabolic decompensation and the estimation of its severity. In contrast, analyses of organic acids, acylcarnitines and carnitine status were less discriminative. In conclusion, careful history taking and identification of suspicious symptoms in combination with a small number of rapidly available biochemical parameters are helpful to differentiate compensated metabolic condition and (impending) metabolic crisis and to decide when to start an emergency treatment.

  9. Classic and contemporary approaches to modeling biochemical reactions

    PubMed Central

    Chen, William W.; Niepel, Mario; Sorger, Peter K.

    2010-01-01

    Recent interest in modeling biochemical networks raises questions about the relationship between often complex mathematical models and familiar arithmetic concepts from classical enzymology, and also about connections between modeling and experimental data. This review addresses both topics by familiarizing readers with key concepts (and terminology) in the construction, validation, and application of deterministic biochemical models, with particular emphasis on a simple enzyme-catalyzed reaction. Networks of coupled ordinary differential equations (ODEs) are the natural language for describing enzyme kinetics in a mass action approximation. We illustrate this point by showing how the familiar Briggs-Haldane formulation of Michaelis-Menten kinetics derives from the outer (or quasi-steady-state) solution of a dynamical system of ODEs describing a simple reaction under special conditions. We discuss how parameters in the Michaelis-Menten approximation and in the underlying ODE network can be estimated from experimental data, with a special emphasis on the origins of uncertainty. Finally, we extrapolate from a simple reaction to complex models of multiprotein biochemical networks. The concepts described in this review, hitherto of interest primarily to practitioners, are likely to become important for a much broader community of cellular and molecular biologists attempting to understand the promise and challenges of “systems biology” as applied to biochemical mechanisms. PMID:20810646

  10. Biosensors and bioelectronics on smartphone for portable biochemical detection.

    PubMed

    Zhang, Diming; Liu, Qingjun

    2016-01-15

    Smartphone has been widely integrated with sensors, such as test strips, sensor chips, and hand-held detectors, for biochemical detections due to its portability and ubiquitous availability. Utilizing built-in function modules, smartphone is often employed as controller, analyzer, and displayer for rapid, real-time, and point-of-care monitoring, which can significantly simplify design and reduce cost of the detecting systems. This paper presents a review of biosensors and bioelectronics on smartphone for portable biochemical detections. The biosensors and bioelectronics based on smartphone can mainly be classified into biosensors using optics, surface plasmon resonance, electrochemistry, and near-field communication. The developments of these biosensors and bioelectronics on smartphone are reviewed along with typical biochemical detecting cases. Sensor strategies, detector attachments, and coupling methods are highlighted to show designs of the compact, lightweight, and low-cost sensor systems. The performances and advantages of these designs are introduced with their applications in healthcare diagnosis, environment monitoring, and food evaluation. With advances in micro-manufacture, sensor technology, and miniaturized electronics, biosensor and bioelectronic devices on smartphone can be used to perform biochemical detections as common and convenient as electronic tag readout in foreseeable future.

  11. The biochemical properties of antibodies and their fragments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunoglobulins (Ig) or antibodies are a powerful molecular recognition tools that can be used to identify minute quantities of a given target analyte. Their antigen binding properties define both the sensitivity and selectivity of an immunoassay. Understanding the biochemical properties of this c...

  12. A MULTILAYER BIOCHEMICAL DRY DEPOSITION MODEL 1. MODEL FORMULATION

    EPA Science Inventory

    A multilayer biochemical dry deposition model has been developed based on the NOAA Multilayer Model (MLM) to study gaseous exchanges between the soil, plants, and the atmosphere. Most of the parameterizations and submodels have been updated or replaced. The numerical integration ...

  13. A MULTILAYER BIOCHEMICAL DRY DEPOSITION MODEL 2. MODEL EVALUATION

    EPA Science Inventory

    The multilayer biochemical dry deposition model (MLBC) described in the accompanying paper was tested against half-hourly eddy correlation data from six field sites under a wide range of climate conditions with various plant types. Modeled CO2, O3, SO2<...

  14. Physiologic and biochemical aspects of skeletal muscle denervation and reinnervation

    NASA Technical Reports Server (NTRS)

    Max, S. R.; Mayer, R. F.

    1984-01-01

    Some of the physiologic and biochemical changes that occur in mammalian skeletal muscle following denervation and reinnervation are considered and some comparisons are made with changes observed following altered motor function. The nature of the trophic influence by which nerves control muscle properties are discussed, including the effects of choline acetyltransferase and acetylcholinesterase and the role of the acetylcholine receptor.

  15. Metstoich--Teaching Quantitative Metabolism and Energetics in Biochemical Engineering

    ERIC Educational Resources Information Center

    Wong, Kelvin W. W.; Barford, John P.

    2010-01-01

    Metstoich, a metabolic calculator developed for teaching, can provide a novel way to teach quantitative metabolism to biochemical engineering students. It can also introduce biochemistry/life science students to the quantitative aspects of life science subjects they have studied. Metstoich links traditional biochemistry-based metabolic approaches…

  16. [Strategies for diagnosis and biochemical control of porphyrias].

    PubMed

    Brock, Axel; Rasmussen, Lars Melholt; Hertz, Jens Michael

    2014-02-17

    Porphyrias are rare, distinct and well characterized diseases due to impairment of one of the eight steps in the biosynthesis of haem, which is the functional group of haemoglobin, myoglobin and cytochromes, including the cytochrome P-450 family. The actual strategies for diagnosis and biochemical control of the five most common porphyrias are described.

  17. Development of a new first-aid biochemical detector

    NASA Astrophysics Data System (ADS)

    Hu, Jingfei; Liao, Haiyang; Su, Shilin; Ding, Hao; Liu, Suquan

    2016-10-01

    The traditional biochemical detector exhibits poor adaptability, inconvenient carrying and slow detection, which can't meet the needs of first-aid under field condition like natural or man-made disasters etc. Therefore a scheme of first-aid biochemical detector based on MOMES Micro Spectrometer, UV LED and Photodiode was proposed. An optical detection structure combined continuous spectrum sweep with fixed wavelength measurement was designed, which adopted mobile detection optical path consisting of Micro Spectrometer and Halogen Lamp to detect Chloride (Cl-), Creatinine (Cre), Glucose (Glu), Hemoglobin (Hb). The UV LED and Photodiode were designed to detect Potassium (K-), Carbon dioxide (CO2), Sodium (Na+). According to the field diagnosis and treatment requirements, we designed the embedded control hardware circuit and software system, the prototype of first-aid biochemical detector was developed and the clinical trials were conducted. Experimental results show that the sample's absorbance repeatability is less than 2%, the max coefficient of variation (CV) in the batch repeatability test of all 7 biochemical parameters in blood samples is 4.68%, less than the clinical requirements 10%, the correlation coefficient (R2) in the clinical contrast test with AU5800 is almost greater than 0.97. To sum up, the prototype meets the requirements of clinical application.

  18. [Experiments using rats on Kosmos biosatellites: morphologic and biochemical studies].

    PubMed

    Il'in, E A; Kaplanskiĭ, A S; Savina, E A

    1989-01-01

    Results of morphological and biochemical investigations of rats flown on Cosmos biosatellites are discussed. It is emphasized that most changes occurring during exposure to microgravity are directly or indirectly related to lower musculoskeletal loads which in turn produce deconditioning of different physiological systems and organism as a whole. It is concluded that this deconditioning is associated with both metabolic and structural changes.

  19. Biochemical Markers of Brain Injury: Applications to Combat Casualty Care

    DTIC Science & Technology

    2004-09-01

    these failures [6]. Unlike other organ-based diseases where rapid diagnosis employing biomarkers (usually involving blood tests) prove invaluable...implementation of appropriate triage and medical management. Criteria For Biochemical/Surrogate Markers: In the course of research on biomarkers ...our laboratories have developed criteria for biomarker development. As reflected in the present proposal, useful biomarkers should employ readily

  20. Biochemical Parameters of Orienteers Competing in a Long Distance Race.

    ERIC Educational Resources Information Center

    Mikan, Vladimir; And Others

    1992-01-01

    Measured important biochemical parameters in a group of orienteers two hours before beginning and immediately after an orienteering marathon. Found levels of dehydration. Suggests a drinking regimen which is designed for orienteering races. Concludes that no runner having kidney or liver abnormalities or changes in the urine should be allowed to…