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Sample records for biochemical evolution ii

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

    Science.gov (United States)

    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. PMID:9860941

  2. Evolution of long-term coloration trends with biochemically unstable ingredients.

    Science.gov (United States)

    Higginson, Dawn M; Belloni, Virginia; Davis, Sarah N; Morrison, Erin S; Andrews, John E; Badyaev, Alexander V

    2016-05-25

    The evolutionarily persistent and widespread use of carotenoid pigments in animal coloration contrasts with their biochemical instability. Consequently, evolution of carotenoid-based displays should include mechanisms to accommodate or limit pigment degradation. In birds, this could involve two strategies: (i) evolution of a moult immediately prior to the mating season, enabling the use of particularly fast-degrading carotenoids and (ii) evolution of the ability to stabilize dietary carotenoids through metabolic modification or association with feather keratins. Here, we examine evolutionary lability and transitions between the two strategies across 126 species of birds. We report that species that express mostly unmodified, fast-degrading, carotenoids have pre-breeding moults, and a particularly short time between carotenoid deposition and the subsequent breeding season. Species that expressed mostly slow-degrading carotenoids in their plumage accomplished this through increased metabolic modification of dietary carotenoids, and the selective expression of these slow-degrading compounds. In these species, the timing of moult was not associated with carotenoid composition of plumage displays. Using repeated samples from individuals of one species, we found that metabolic modification of dietary carotenoids significantly slowed their degradation between moult and breeding season. Thus, the most complex and colourful ornamentation is likely the most biochemically stable in birds, and depends less on ecological factors, such as moult timing and migration tendency. We suggest that coevolution of metabolic modification, selective expression and biochemical stability of plumage carotenoids enables the use of unstable pigments in long-term evolutionary trends in plumage coloration. PMID:27194697

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

    Science.gov (United States)

    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)

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

    Science.gov (United States)

    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. PMID:27294968

  5. Mutation and biochemical analysis in carnitine palmitoyltransferase type II (CPT II) deficiency

    DEFF Research Database (Denmark)

    Olpin, S E; Afifi, A; Clark, S;

    2003-01-01

    Carnitine palmitoyltransferase type II (CPT II) deficiency has three basic phenotypes, late-onset muscular (mild), infantile/juvenile hepatic (intermediate) and severe neonatal. We have measured fatty acid oxidation and CPT II activity and performed mutation studies in 24 symptomatic patients rep...

  6. Planetary nebulae abundances and stellar evolution II

    NARCIS (Netherlands)

    Pottasch, S. R.; Bernard-Salas, J.

    2010-01-01

    Context. In recent years mid-and far infrared spectra of planetary nebulae have been analysed and lead to more accurate abundances. It may be expected that these better abundances lead to a better understanding of the evolution of these objects. Aims. The observed abundances in planetary nebulae are

  7. Biochemical Characterization of the Split Class II Ribonucleotide Reductase from Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Mikael Crona

    Full Text Available The opportunistic pathogen Pseudomonas aeruginosa can grow under both aerobic and anaerobic conditions. Its flexibility with respect to oxygen load is reflected by the fact that its genome encodes all three existing classes of ribonucleotides reductase (RNR: the oxygen-dependent class I RNR, the oxygen-indifferent class II RNR, and the oxygen-sensitive class III RNR. The P. aeruginosa class II RNR is expressed as two separate polypeptides (NrdJa and NrdJb, a unique example of a split RNR enzyme in a free-living organism. A split class II RNR is also found in a few closely related γ-Proteobacteria. We have characterized the P. aeruginosa class II RNR and show that both subunits are required for formation of a biologically functional enzyme that can sustain vitamin B12-dependent growth. Binding of the B12 coenzyme as well as substrate and allosteric effectors resides in the NrdJa subunit, whereas the NrdJb subunit mediates efficient reductive dithiol exchange during catalysis. A combination of activity assays and activity-independent methods like surface plasmon resonance and gas phase electrophoretic macromolecule analysis suggests that the enzymatically active form of the enzyme is a (NrdJa-NrdJb2 homodimer of heterodimers, and a combination of hydrogen-deuterium exchange experiments and molecular modeling suggests a plausible region in NrdJa that interacts with NrdJb. Our detailed characterization of the split NrdJ from P. aeruginosa provides insight into the biochemical function of a unique enzyme known to have central roles in biofilm formation and anaerobic growth.

  8. Hybrid Differential Evolution for Estimation of Kinetic Parameters for Biochemical Systems

    Institute of Scientific and Technical Information of China (English)

    ZHAO Chao; XU Qiaoling; LIN Siming; LI Xuelai

    2013-01-01

    Determination of the optimal model parameters for biochemical systems is a time consuming iterative process.In this study,a novel hybrid differential evolution(DE)algorithm based on the differential evolution technique and a local search strategy is developed for solving kinetic parameter estimation problems.By combining the merits of DE with Gauss-Newton method,the proposed hybrid approach employs a DE algorithm for identifying promising regions of the solution space followed by use of Gauss-Newton method to determine the optimum in the identified regions.Some well-known benchmark estimation problems are utilized to test the efficiency and the robustness of the proposed algorithm compared to other methods in literature.The comparison indicates that the present hybrid algorithm outperforms other estimation techniques in terms of the global searching ability and the convergence speed.Additionally,the estimation of kinetic model parameters for a feed batch fermentor is carried out to test the applicability of the proposed algorithm.The result suggests that the method can be used to estimate suitable values of model parameters for a complex mathematical model.

  9. Biochemical markers of type II collagen breakdown and synthesis are positioned at specific sites in human osteoarthritic knee cartilage

    DEFF Research Database (Denmark)

    Jensen, Anne-Christine Bay; Levin Andersen, Thomas; Charni-Ben Tabassi, N;

    2007-01-01

    OBJECTIVE: To investigate whether type II collagen turnover markers used for osteoarthritis (OA) activity evaluation in body fluids can be detected at the level of specific histological features of OA cartilage tissue, as well as how they relate with each other at this level. METHODS: Adjacent...... sections were obtained from full-depth cartilage biopsies from 32 OA knees. Immunohistochemistry was performed for Helix-II and CTX-II, which are type II collagen fragments originating from the triple helix and the telopeptide region, respectively, and believed to reflect distinct breakdown events, as well...... as for type IIA N propeptide (PIIANP), a biochemical marker reflecting synthesis of type IIA collagen. RESULTS: Helix-II and CTX-II were detected in areas where collagen damage was reported previously, most frequently around chondrocytes, but also frequently in regions not previously investigated...

  10. Synthesis, structural and biochemical activity studies of a new hexadentate Schiff base ligand and its Cu(II), Ni(II), and Co(II) complexes

    Science.gov (United States)

    Ekmekcioglu, Pinar; Karabocek, Nevin; Karabocek, Serdar; Emirik, Mustafa

    2015-11-01

    A new Schiff base ligand (H2L) and its metal complexes have been prepared and characterized by elemental analysis, magnetic moment and spectral studies. The comparative in-vitro antimicrobial activities against various pathogens with reference to known antibiotics activity under the standard control of different concentrations revealed that the metal complexes (6-8) showed enhanced antimicrobial activities in general as compared to free ligand. As an exception, the free ligand showed better activity against Trichoderma. The antifungal activity experiments were performed in triplicate. The order of biochemical activity for metal complexes were observed as in the following. CuL > CoL > NiL, which is exactly same as the order of stability constants of these complexes. Additionally, we performed DFT and TD-DFT calculation for free ligand and Cu(II) complex to support the experimental data. The geometries of the Cu(II) complex have been optimized using the B3LYP level of theory. The theoretical calculations confirm that the copper (II) center exhibits a distorted square pyramidal geometry which is favored by experimental results.

  11. The Kinematic Evolution of Strong MgII Absorbers

    CERN Document Server

    Mshar, Andrew C; Lynch, Ryan S; Churchill, Chris; Kim, Tae-Sun

    2007-01-01

    We consider the evolution of strong (W_r(2796) > 0.3A) MgII absorbers, most of which are closely related to luminous galaxies. Using 20 high resolution quasar spectra from the VLT/UVES public archive, we examine 33 strong MgII absorbers in the redshift range 0.3 < z < 2.5. We compare and supplement this sample with 23 strong MgII absorbers at 0.4 < z < 1.4 observed previously with HIRES/Keck. We find that neither equivalent width nor kinematic spread (the optical depth weighted second moment of velocity) of MgII2796 evolve. However, the kinematic spread is sensitive to the highest velocity component, and therefore not as sensitive to additional weak components at intermediate velocities relative to the profile center. The fraction of absorbing pixels within the full velocity range of the system does show a trend of decreasing with decreasing redshift. Most high redshift systems (14/20) exhibit absorption over the entire system velocity range, which differs from the result for low redshift systems ...

  12. THE EVOLUTION OF SOME BIOCHEMICAL PARAMETERS IN THE HONEYBEES’ HAEMOLYMPH (A. M. CARPATHICA COLLECTED IN THE INACTIVE SEASON

    Directory of Open Access Journals (Sweden)

    AGRIPINA SAPCALIU

    2013-12-01

    Full Text Available The biochemical analyses of the blood are largely used for the routine diagnosis and especially for the metabolic survey in farm animals. These facts conduct us to the idea that similar analyses, applied on honeybee hemolymph, could be used IN monitoring the healthy state of honeybee colonies. The present studies represent preliminary researches, which aimed to investigate the variability of the main biochemical parameters in the hemolymph of the healthy honeybees (Apis mellifera in inactive season. The researches were carried out on honeybee samples collected from 5 honeybee colonies belonging to a breeding apiary of the Institute for Beekeeping Research and Development from Bucharest. In order to perform the biochemical analyses, the honeybees samples, consisting in 50 individuals on sample (10 individuals/colony were randomly collected and their haemolimph collected, at different time intervals, in inactive season (fall-winter. Totally, there were collected 250 haemolyph samples in a 2 years interval and the following 21 biochemical parameters were analysed: GLU, HDL-c, ALP, T-cho, Tprot, Alb., BUN, LDH, CPK,, Mg, IP, GGT, GOT, GPT, Ca, Cre,, Amy, T–BIL, TG, UA.. The test was carried out after the collection and processing of the samples using the SPOTCHEM EZSP4430, equipment with dry kits, the slides technique, respectively .During the 2nd part of the inactive season, the values of most biochemical parameters increase in different proportions, their levels being maintained also in the first part of the active seasons (April, May, June.The values obtained for the main studied biochemical parameters in the haemolymph of the healthy honeybees collected from honeybee colonies kept in natural conditions show a highly variable evolution in the two consecutive years of experiments during the inactive season.

  13. Chemical evolution of two-component galaxies. II

    International Nuclear Information System (INIS)

    In order to confirm and refine the results obtained in a previous paper the chemical evolution of two-component (spheroid + disk) galaxies is derived rejecting the instantaneous recycling approximation, by means of numerical computations, accounting for (i) the collapse phase of the gas, assumed to be uniform in density and composition, and (ii) a birth-rate stellar function. Computations are performed relatively to the solar neighbourhood and to model galaxies which closely resemble the real morphological sequence: in both cases, numerical results are compared with analytical ones. The numerical models of this paper constitute a first-order approximation, while higher order approximations could be made by rejecting the hypothesis of uniform density and composition, and making use of detailed dynamical models. (Auth.)

  14. River water quality model no. 1 (RWQM1): II. Biochemical process equations

    DEFF Research Database (Denmark)

    Reichert, P.; Borchardt, D.; Henze, Mogens;

    2001-01-01

    In this paper, biochemical process equations are presented as a basis for water quality modelling in rivers under aerobic and anoxic conditions. These equations are not new, but they summarise parts of the development over the past 75 years. The primary goals of the presentation are to stimulate...... communication among modellers and field-oriented researchers of river water quality and of wastewater treatment, to facilitate practical application of river water quality modelling, and to encourage the use of elemental mass balances for the derivation of stoichiometric coefficients of biochemical...

  15. Metronomic cyclophosphamide therapy in hormone-naive patients with non-metastatic biochemical recurrent prostate cancer: a phase II trial.

    Science.gov (United States)

    Calcagno, Fabien; Mouillet, Guillaume; Adotevi, Olivier; Maurina, Tristan; Nguyen, Thierry; Montcuquet, Philippe; Curtit, E; Kleinclauss, F; Pivot, Xavier; Borg, Christophe; Thiery-Vuillemin, Antoine

    2016-08-01

    After curative local therapy, biochemical recurrence is a mode of relapse among patient with prostate cancer (PC). Deferring androgen deprivation therapy (ADT) or offering non-hormonal therapies may be an appropriate option for these non-symptomatic patients with no proven metastases. Metronomic cyclophosphamide (MC) has shown activity in metastatic PC setting and was chosen to be assessed in biochemical relapse. This prospective single-arm open-label phase II study was conducted to evaluate MC regimen in patients with biochemical recurrent PC. MC was planned to be administered orally at a daily dose of 50 mg for 6 months. Primary endpoint was PSA response. Thirty-eight patients were included and treated. Median follow-up was 45.5 months (range 17-100). Among them, 14 patients (37 %) achieved PSA stabilisation and 22 patients (58 %) experienced PSA progression. Response rate was 5 % with one complete response (2.6 %), and 1 partial response with PSA decrease >50 % (2.6 %). The median time until androgen deprivation therapy initiation was around 15 months. The treatment was well tolerated. Neither grade 3-4 toxicity nor serious adverse events were observed. This first prospective clinical trial with MC therapy in patients with non-metastatic biochemical recurrence of PC displayed modest efficacy when measured with PSA response rate, without significant toxicity. It might offer a new safe and non-expensive option to delay initiation of ADT. These results would need to be confirmed with larger prospective randomised trials. PMID:27400698

  16. Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action.

    Science.gov (United States)

    Djoko, Karrera Y; Paterson, Brett M; Donnelly, Paul S; McEwan, Alastair G

    2014-04-01

    The copper(II) complexes of bis-thiosemicarbazones (Cu(btsc)) such as Cu(atsm) and Cu(gtsm) are neutral, lipophilic compounds that show promise as therapeutics for the treatment of certain neurological diseases and cancers. Although the effects of these compounds have been described at the cellular level, there is almost no information about their biochemical mode of action. In this work, we showed that Cu(atsm) and Cu(gtsm) displayed antimicrobial activities against the human obligate pathogen Neisseria gonorrhoeae that were more than 100 times more potent than Cu(NO3)2 salt alone. Treatment with Cu(btsc) also produced phenotypes that were consistent with copper poisoning, but the levels of intracellular copper were undetectable by ICP MS. We observed that Cu(btsc) interacted with proteins in the cell membrane. Systematic measurements of O2 uptake further demonstrated that treatment with both Cu(atsm) and Cu(gtsm) led to dose-dependent inhibition of respiratory electron transfer processes via succinate and NADH dehydrogenases. These dehydrogenases were not inhibited by a non-btsc source of Cu(II). The results led us to conclude that the biochemical mechanism of Cu(btsc) action is likely more complex than the present, simplistic model of copper release into the cytoplasm. PMID:24435165

  17. Epidemiology of Candida infection. II. Application of biochemical methods for typing of Candida albicans strains.

    Science.gov (United States)

    Budak, A

    1990-01-01

    Biochemical profiles of 350 C. albicans isolates from five towns in Poland and from Freiburg in Germany were determined on the basis of nine biochemical tests of Odds and Abbott method. API 20 C AUX system and additionally a resistogram. The analysis of the strains according to Odds' and Abbotts's system showed that investigated strains can be typed into 9 profile codes of common biochemical patterns. There were some differences among the profiles according to their geographical origin and anatomical sources of the isolation. On the basis of the ability C. albicans strains to assimilate of carbon sources, 350 isolates were categorised into 13 separate auxotrophic profiles with the major one: 2,576,174 accounting for 81% of the total. The majority of the investigated isolates were susceptible to antifungal agents (83%). A disproportionate distribution of auxotrophic profiles limited the use of resistogram method and API 20 C AUX as systems for typing C. albicans strains. On the other hand, the method of Odds and Abbott provides valuable criteria for typing of C. albicans. PMID:2130802

  18. Biochemical and developmental characterization of carbonic anhydrase II from chicken erythrocytes

    Directory of Open Access Journals (Sweden)

    Orito Kensuke

    2011-03-01

    Full Text Available Abstract Background Carbonic anhydrase (CA of the chicken has attracted attention for a long time because it has an important role in the eggshell formation. The developmental profile of CA-II isozyme levels in chicken erythrocytes has not been determined or reported. Furthermore, the relations with CA-II in erythrocyte and egg production are not discussed. In the present study, we isolated CA-II from erythrocytes of chickens and determined age-related changes of CA-II levels in erythrocytes. Methods Chicken CA-II was purified by a combination of column chromatography. The levels of CA-II in the hemolysate of the chicken were determined using the ELISA system in blood samples from 279 female chickens, ages 1 to 93 weeks, 69 male chickens, ages 3 to 59 weeks and 52 weeks female Araucana-chickens. Results The mean concentration of CA-II in hemolysate from 1-week-old female was 50.8 ± 11.9 mg/g of Hb. The mean levels of CA-II in 25-week-old (188.1 ± 82.6 mg/g of Hb, 31-week-old (193.6 ± 69.7 mg/g of Hb and 49-week-old (203.8 ± 123.5 mg/g of Hb female-chickens showed the highest level of CA-II. The levels of CA-II in female WL-chickens significantly decreased at 63 week (139.0 ± 19.3 mg/g of Hb. The levels of CA-II in female WL-chicken did not change from week 63 until week 93.The mean level of CA-II in hemolysate of 3-week-old male WL-chickens was 78.3 ± 20.7 mg/g of Hb. The levels of CA-II in male WL-chickens did not show changes in the week 3 to week 59 timeframe. The mean level of CA-II in 53-week-old female Araucana-chickens was 23.4 ± 1.78 mg/g of Hb. These levels of CA-II were about 11% of those of 49-week-old female WL-chickens. Simple linear regression analysis showed significant associations between the level of CA-II and egg laying rate from 16 week-old at 63 week-old WL-chicken (p Conclusions Developmental changes and sexual differences of CA-II concentration in WL-chicken erythrocytes were observed. The concentration of CA-II in

  19. Water chemistry of Atucha II PHWVR. Design concepts and evolution

    International Nuclear Information System (INIS)

    present the involved tasks that have to be fulfilled, world water chemistry criteria at the design time and premises to be adopted for CNA II reactor. Also, evolution of water chemistry control criteria including safety aspects and better understanding of degradation phenomena and their mitigation must be included. The paper concludes with a set of specifications example for the primary circuit, the water-steam cycle and auxiliary circuits and the comparison to international standards. (author)

  20. The Chemical Evolution of Globular Clusters - II. Metals and Fluorine

    CERN Document Server

    Sanchez-Blazquez, Patricia; Gibson, Brad K; Karakas, Amanda I; Pilkington, Kate; Calura, Francesco

    2011-01-01

    In the first paper in this series, we proposed a new framework in which to model the chemical evolution of globular clusters. This model, is predicated upon the assumption that clusters form within an interstellar medium enriched locally by the ejecta of a single Type Ia supernova and varying numbers of asymptotic giant branch stars, superimposed on an ambient medium pre-enriched by low-metallicity Type II supernovae. Paper I was concerned with the application of this model to the observed abundances of several reactive elements and so-called non-metals for three classical intermediate-metallicity clusters, with the hallmark of the work being the successful recovery of many of their well-known elemental and isotopic abundance anomalies. Here, we expand upon our initial analysis by (a) applying the model to a much broader range of metallicities (from the factor of three explored in Paper I, to now, a factor of ~50; i.e., essentially, the full range of Galactic globular cluster abundances, and (b) incorporating...

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

    Directory of Open Access Journals (Sweden)

    Zo Young-Gun

    2009-04-01

    Full Text Available Abstract 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

  2. Bacterial Bolsheviks: PS II and the Evolution of the Oxygenic Revolution

    Science.gov (United States)

    Kopp, R. E.; Kirschvink, J. L.; Newman, D. K.; Nash, C. Z.; Hilburn, I. A.

    2003-12-01

    After the rise of life itself, the most radical transformation of Earth's biogeochemical cycles was the transition from an anoxic to an oxic world. Though various studies have suggested O2 made its first bulk appearance in the atmosphere some time between 3.8 and 2.1 Ga, virtually all analyses agree the production of large quantities of free O2 was triggered by the evolution of oxygenic photosynthesis. We suggest the oldest strong geological evidence for O2 is the 2.22 Ga Kalahari Mn member of the Hotazel BIF (1), as in the oceans only free O2 can oxidize soluble Mn(II) into insoluble Mn(IV). Some have argued, however, that oxygenic cyanobacteria had originated by 2.7 Ga. The ˜500 Myr "gap" has often been interpreted as the timescale for gradual evolutionary improvement of the O2-generating system. Biochemical and genomic analyses of photosynthetic bacteria indicate that photosystems I and II, which operate together in cyanobacteria, had a long history of parallel development. Green sulfur bacteria and heliobacteria use PS-II, while green non-sulfur and purple bacteria use PS-I; none can use H2O as an electron donor. Recent genetic analyses show lateral gene transfer was rampant among photosynthetic lineages (2). Moreover, extant cyanobacteria shut down PS-II in the presence of an alternative electron donor like H2S. This suggests PS-I and PS-II came together with their functions intact. Hence, most `debugging' of the two systems predates their merger in the ancestor of modern cyanobacteria. The time interval between the lateral transfer events and the evolution of oxygenic photosynthesis could thus have been geologically short. We suggest the ˜500 Myr "gap" may result from misinterpretations. The presence of oxygenic photosynthesis is uncertain before the deposition of the Hotazel formation, in the aftermath of the Makganyene glaciation (1). A simple model of nutrient and reductant fluxes argues that, once triggered, the oxygenation of a reducing surface

  3. Insights into the molecular evolution of HslU ATPase through biochemical and mutational analyses.

    Directory of Open Access Journals (Sweden)

    Kwang Hoon Sung

    Full Text Available The ATP-dependent HslVU complexes are found in all three biological kingdoms. A single HslV protease exists in each species of prokaryotes, archaea, and eukaryotes, but two HslUs (HslU1 and HslU2 are present in the mitochondria of eukaryotes. Previously, a tyrosine residue at the C-terminal tail of HslU2 has been identified as a key determinant of HslV activation in Trypanosoma brucei and a phenylalanine at the equivalent position to E. coli HslU is found in T. brucei HslU1. Unexpectedly, we found that an F441Y mutation in HslU enhanced the peptidase and caseinolytic activity of HslV in E. coli but it showed partially reduced ATPase and SulA degradation activity. Previously, only the C-terminal tail of HslU has been the focus of HslV activation studies. However, the Pro315 residue interacting with Phe441 in free HslU has also been found to be critical for HslV activation. Hence, our current biochemical analyses explore the importance of the loop region just before Pro315 for HslVU complex functionality. The proline and phenylalanine pair in prokaryotic HslU was replaced with the threonine and tyrosine pair from the functional eukaryotic HslU2. Sequence comparisons between multiple HslUs from three different biological kingdoms in combination with biochemical analysis of E. coli mutants have uncovered important new insights into the molecular evolutionary pathway of HslU.

  4. Molecular and biochemical studies of the evolution, infection and transmission of insect bunyaviruses.

    Science.gov (United States)

    Bishop, D H; Beaty, B J

    1988-10-31

    Members of the Bunyaviridae family of RNA viruses (bunyaviruses, hantaviruses, nairoviruses, phleboviruses and uukuviruses) have been studied at the molecular and genetic level to understand the basis of their evolution and infection in vertebrate and invertebrate (arthropod) hosts. With the exception of the hantaviruses, these viruses infect and are transmitted by a variety of blood-sucking arthropods (mosquitoes, phlebotomines, gnats, ticks, etc.). The viruses are responsible for infection of various vertebrate species, occasionally causing human disease, morbidity and mortality (e.g. Rift Valley fever, Crimean-Congo haemorrhagic fever, Korean haemorrhagic fever). Genetic and molecular analyses of bunyaviruses have established the coding assignments of the three viral RNA species and documented which viral gene products determine host range and virulence. Ecological studies, with molecular techniques, have provided evidence for bunyavirus evolution in nature through genetic drift (involving the accumulation of point mutations) and shift (RNA-segment reassortment).

  5. Berberis Fruit Extract and Biochemical Parameters in Patients With Type II Diabetes

    OpenAIRE

    Moazezi, Zolikha; Qujeq, Durdi

    2014-01-01

    Background: Diabetes mellitus is a common medical problem. There is in fact a growing body of literature on plants used for the treatment of diabetes. Plant materials attracted considerable interest of scientists. In this respect, in the past few years, attempts were made to use natural plant products for the treatment of patients with diabetes. Objectives: The aim of this study was to investigate the effect of Berberis fruit extract to achieve glycemic control in patients with Type II diabet...

  6. Specificity of protein — Nucleic acid interaction and the biochemical evolution

    Science.gov (United States)

    Podder, S. K.; Basu, H. S.

    1984-12-01

    The water soluble carbodiimide mediated condensation of dipeptides of the general form Gly-X was carried out in the presence of mono- and poly-nucleotides. The observed yield of the tetrapeptide was found to be higher for peptide-nucleotide system of higher interaction specificity following mainly the anticodon-amino acid relationship (Basu, H.S. & Podder, S.K., 1981, Ind. J. Biochem. Biophys., 19, 251 253). The yield of the condensation product of L-peptide was more because of its higher interaction specificity. The extent of the racemization during the condensation of Gly-L-Phe, Gly-L-Tyr and Gly-D-Phe was found to be dependent on the specificity of the interaction —the higher the specificity, the lesser the racemization. The product formed was shown to have a catalytic effect on the condensation reaction. These data thus provide a mechanism showing how the specific interaction between amino acids/dipeptides and nucleic acids could lead to the formation of the ‘primitive’ translation machinery.

  7. THE EVOLUTION OF BIOCHEMICAL OXIDATION OF AMMONIA IONS IN SMALL RIVERS WATER

    Directory of Open Access Journals (Sweden)

    Elena Mosanu

    2010-06-01

    Full Text Available Nitrification is the oxidation of ammonia to nitrate, via nitrite and it occupies a central position within the global nitrogen cycle. Nitrifying bacteria are the organisms capable of converting the most reduced form of nitrogen, ammonia, to the most oxidized form, nitrate, but their activity is influenced by pollution level. Starting with the assumption that pollution of small internal water courses in the Republic of Moldova remained severe (phenols, detergents and copper regularly exceed the MACs the work presented in the paper discusses the evolution of ammonia ions nitrification in the water of river Prut tributaries and its correlation with the content of pollutants in water: surface-active substances, Cu, BOD5, COD and other compounds.

  8. Evolution of science II: Insights into working of Nature

    CERN Document Server

    Vahia, M N

    2016-01-01

    We attempt to provide a comprehensive model of evolution of science across millennia taking into account the contributions of other intellectual traditions, cultural value system and increasing in sophistication of humans in their study of nature. We also briefly discuss the role of technology and its interplay in the evolution of science. We identify five primary approaches to the study of nature, namely ad hoc formulations, religious approach, pragmatic approach, axiomatic approach and the logic based approach. Each of these approaches have had their prime periods and have contributed significantly to human understanding of nature and have also overlapped within a society. Each approach has had a central role over human evolution at some stage. We surmise that the currently dominant axiomatic method will reach its limits due to complexity of the system and may never be fully formalised. We suggest that the future progress of science will more be a logic based approach where experimentation and simulations r...

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

    Science.gov (United States)

    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. PMID:23252450

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

    Science.gov (United States)

    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.

  11. Thermodynamic evolution of the cosmological baryonic gas II. Galaxy formation

    CERN Document Server

    Alimi, J M

    2004-01-01

    The problem of galaxy formation and its dependence on thermodynamic properties is addressed by using Eulerian hydrodynamic numerical simulations of large scale structure formation. Global galaxy properties are explored in simulations including gravitation, shock heating and cooling processes, and following self-consistently the chemical evolution of a primordial composition hydrogen-helium plasma without assuming collisional ionization equilibrium. The galaxy formation model is mainly based on the identification of converging dense cold gas regions. We show that the evolution at low redshift of the observed cosmic star formation rate density is reproduced, and that the galaxy-like object mass function is dominated by low-mass objects. The galaxy mass functions are well described by a two power-law Schechter function whose parameters are in good agreement with observational fits of the galaxy luminosity function. The high-mass end of the galaxy mass function includes objects formed at early epochs and residing...

  12. The evolution of substructure II: linking dynamics to environment

    CERN Document Server

    Gill, S P D; Gibson, B K; Dopita, M A

    2004-01-01

    We present results from a series of high-resolution N-body simulations that focus on the formation and evolution of eight dark matter halos, each of order a million particles within the virial radius. We follow the time evolution of hundreds of satellite galaxies with unprecedented time resolution, relating their physical properties to the differing halo environmental conditions. The self-consistent cosmological framework in which our analysis was undertaken allows us to explore satellite disruption within live host potentials, a natural complement to earlier work conducted within static potentials. Our host halos were chosen to sample a variety of formation histories, ages, and triaxialities; despite their obvious differences, we find striking similarities within the associated substructure populations. Namely, all satellite orbits follow nearly the same eccentricity distribution with a correlation between eccentricity and pericentre. We also find that the destruction rate of the substructure population is n...

  13. Classification and evolution of type II CRISPR-Cas systems

    OpenAIRE

    Chylinski, Krzysztof; Makarova, Kira S.; Charpentier, Emmanuelle; Eugene V Koonin

    2014-01-01

    The CRISPR-Cas systems of archaeal and bacterial adaptive immunity are classified into three types that differ by the repertoires of CRISPR-associated (cas) genes, the organization of cas operons and the structure of repeats in the CRISPR arrays. The simplest among the CRISPR-Cas systems is type II in which the endonuclease activities required for the interference with foreign deoxyribonucleic acid (DNA) are concentrated in a single multidomain protein, Cas9, and are guided by a co-processed ...

  14. Late Spectral Evolution of SN 1987A: II. Line Emission

    OpenAIRE

    Kozma, Cecilia; Fransson, Claes

    1997-01-01

    Using the temperature and ionization calculated in our previous paper, we model the spectral evolution of SN 1987A. The IR-catastrophe is seen in the metal lines as a transition from thermal to non-thermal excitation, most clearly in the [O I] 6300, 6364 lines. The distribution of the different zones, and therefore the gamma-ray deposition, is determined from the line profiles of the most important lines, where possible. We find the total mass of hydrogen-rich gas to be ~7.7 Msun. The helium ...

  15. Animal lectins as self/non-self recognition molecules. Biochemical and genetic approaches to understanding their biological roles and evolution.

    Science.gov (United States)

    Vasta, G R; Ahmed, H; Fink, N E; Elola, M T; Marsh, A G; Snowden, A; Odom, E W

    1994-04-15

    In recent years, the significant contributions from molecular research studies on animal lectins have elucidated structural aspects and provided clues not only to their evolution but also to their multiple biological functions. The experimental evidence has suggested that distinct, and probably unrelated, groups of molecules are included under the term "lectin." Within the invertebrate taxa, major groups of lectins can be identified: One group would include lectins that show significant homology to membrane-integrated or soluble vertebrate C-type lectins. The second would include those beta-galactosyl-specific lectins homologous to the S-type vertebrate lectins. The third group would be constituted by lectins that show homology to vertebrate pentraxins that exhibit lectin-like properties, such as C-reactive protein and serum amyloid P. Finally, there are examples that do not exhibit similarities to any of the aforementioned categories. Moreover, the vast majority of invertebrate lectins described so far cannot yet be placed in one or another group because of the lack of information regarding their primary structure. (See Table 1.) Animal lectins do not express a recombinatorial diversity like that of antibodies, but a limited diversity in recognition capabilities would be accomplished by the occurrence of multiple lectins with distinct specificities, the presence of more than one binding site, specific for different carbohydrates in a single molecule, and by certain "flexibility" of the binding sites that would allow the recognition of a range of structurally related carbohydrates. In order to identify the lectins' "natural" ligands, we have investigated the interactions between those proteins and the putative endogenous or exogenous glycosylated substances or cells that may be relevant to their biological function. Results from these studies, together with information on the biochemical properties of invertebrate and vertebrate lectins, including their structural

  16. Properties of Star Clusters - II: Scale Height Evolution of Clusters

    CERN Document Server

    Buckner, Anne S M

    2014-01-01

    Until now it has been impossible to observationally measure how star cluster scale height evolves beyond 1Gyr as only small samples have been available. Here we establish a novel method to determine the scale height of a cluster sample using modelled distributions and Kolmogorov-Smirnov tests. This allows us to determine the scale height with a 25% accuracy for samples of 38 clusters or more. We apply our method to investigate the temporal evolution of cluster scale height, using homogeneously selected sub-samples of Kharchenko et al. (MWSC), Dias et al. (DAML02), WEBDA, and Froebrich et al. (FSR). We identify a linear relationship between scale height and log(age/yr) of clusters, considerably different from field stars. The scale height increases from about 40pc at 1Myr to 75pc at 1Gyr, most likely due to internal evolution and external scattering events. After 1Gyr, there is a marked change of the behaviour, with the scale height linearly increasing with log(age/yr) to about 550pc at 3.5Gyr. The most likely...

  17. Time Evolution of Selected Actinides in TRIGA MARK-II Fuel

    International Nuclear Information System (INIS)

    Study is made on the evolution of several actinides capable of undergoing fission or breeding available on the Malaysian Nuclear Agency (MNA) TRIGA MARK-II fuel. Population distribution of burned fuel in the MNA reactor is determined with a model developed using WIMS. This model simulates fuel conditions in the hottest position in the reactor, thus the location where most of the burn up occurs. Theoretical basis of these nuclide time evolution are explored and compared with the population obtained from our models. Good agreements are found for the theoretical time evolution and the population of Uranium-235, Uranium-236, Uranium-238 and Plutonium-239. (author)

  18. Amphioxus: a peaceful anchovy fillet to illuminate Chordate Evolution (II

    Directory of Open Access Journals (Sweden)

    Jordi Garcia-Fernàndez

    2006-01-01

    Full Text Available The genome of the amphioxus is on the horizon. With Linda Holland and Jeremy Gibson-Brown at the forefront, with all the amphioxus community behind, and with the Joint Genome Institute, the amphioxus genome will see the light this year, 2006. Hope that it will reflect the “prototypical” preduplicative genome of vertebrates. It may answer definitively what the human genome did not: Are we vertebrates octaploid? Will it shed light on the novelties that helped non-chordates to be chordates? And more, will amphioxus, with a simpler genome, be developed to a senior “experimental model system”, allowing the testing of molecular functions in a non-duplicated genome background and allowing genetic modification to “recapitulate” evolution? Thanks to an outstanding collaboration between labs, the laboratory culture of amphioxus is underway after years of hard work in the field. 2007 looks promising for amphioxus research.

  19. Searching for patterns in TJ-II time evolution signals

    International Nuclear Information System (INIS)

    Since fusion plasma experiments generate hundreds of signals, it is important for their analysis to have automatic mechanisms for searching for similarities and retrieving specific data from the signal database. This paper describes a technique for searching in the TJ-II database that combines support vector machines and similarity query methods. Firstly, plasma signals are pre-processed by wavelet transform or discrete Fourier transform to reduce the dimensionality of the problem and to extract their main features. Secondly, support vector machines are used to classify a set of signals by reference to an input signal. Finally, similarity query methods (Euclidean distance and bounding envelope) are used to search the set of signals that best matches the input signal

  20. Adaptation of a Cyanobacterium to a Biochemically Rich Environment in Experimental Evolution as an Initial Step toward a Chloroplast-Like State

    Science.gov (United States)

    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. PMID:24874568

  1. Structure and evolution of low-mass Population II stars

    Science.gov (United States)

    Montalbán, J.; D'Antona, F.; Mazzitelli, I.

    2000-08-01

    The focus of the present paper is on the detailed description of the internal structures of low mass, population II stars, to clarify some issues about these stellar models and, mainly, their present reliability for observational comparisons. We then explore 1) the role of the local convective model; 2) the differences between "grey" and "non grey" models, and between models in which the photospheric boundary conditions are set at different optical depths (τph = 3 or 100); 3) the role of the equation of state (EoS), both in the atmospheric models and in the interior. One of the major conclusions of the paper is a cautionary note about the usage of the additive volume law in EoS calculations. The dependence of the HR diagram locations and mass luminosity relations on metal and helium content are also discussed. A few comparisons with globular cluster stars show that: 1) general consistency of distance scales and morphologies in the HR diagram is found, when comparing ground based measurements in the Johnson B and V bands and observations in the HST bands; 2) a discrepancy between models and observations may exist for more metal rich clusters; 3) the plausible hypothesis that the mass function in the globular cluster NGC 6397 behaves smoothly until the lower limit of the main sequence poses constraints on the mass-luminosity relation at the lowest end of the main sequence. The evolutionary tracks are available at the WEB location http://www.mporzio.astro.it.

  2. H II Regions and Protosolar Abundances in Galactic Chemical Evolution

    Directory of Open Access Journals (Sweden)

    L. Carigi

    2011-01-01

    Full Text Available Presentamos modelos de evolución química del disco galáctico con diferentes rendimientos dependientes de Z. Encontramos que una tasa moderada de pérdida de masa en estrellas masivas de metalicidad solar produce un excelente ajuste con los gradientes de C/H y C/O del disco de la Galaxia. El mejor modelo reproduce: las abundancias de H, He, C y O derivadas de líneas de recombinación en M17, las abundancias protosolares y las relaciones C/O-O/H, C/Fe-Fe/H y O/Fe-Fe/H derivadas de estrellas de la vecindad solar. La concordancia del modelo con las abundancias protosolares implica que el Sol se originó a una distancia galactocéntrica similar a la actual. El modelo para r = 3 kpc implica que una fracción de las estrellas en la dirección del bulbo se formó en el disco interno. Nuestro modelo reproduce la relación C/O-O/H derivada de regiones H II extragalácticas en galaxias espirales.

  3. THE EVOLUTION OF SOME BIOCHEMICAL PARAMETERS IN THE HONEYBEES’ HAEMOLYMPH (A. M. CARPATHICA) COLLECTED IN THE INACTIVE SEASON

    OpenAIRE

    AGRIPINA SAPCALIU; I. RADOI; D. CONDUR; A. SICEANU; ELIZA CAUIA; CRENGUTA PAVEL

    2013-01-01

    The biochemical analyses of the blood are largely used for the routine diagnosis and especially for the metabolic survey in farm animals. These facts conduct us to the idea that similar analyses, applied on honeybee hemolymph, could be used IN monitoring the healthy state of honeybee colonies. The present studies represent preliminary researches, which aimed to investigate the variability of the main biochemical parameters in the hemolymph of the healthy honeybees (Apis mellifera) in inactive...

  4. Begetting machinery IIEvolutionärer Algorithmus und technische Evolution

    Directory of Open Access Journals (Sweden)

    Rothenhäusler, Andie

    2011-10-01

    Full Text Available In the 1970s and 1980s two new approaches to an evolutionary explanation of technology emerged: While a new generation of sociobiologists increasingly started to view animal and human artifacts as an ,extended phenotype’ of humankind historians and sociologists of technology found in an evolutionary genesis of technology a third way between technological determinism and a social construction of technology. This evolution of technology seemed able to explain multi-causal coherences in the genesis of technology applicably by using allegedly simple rules.

  5. Molecular evolution of the capsid gene in human norovirus genogroup II

    Science.gov (United States)

    Kobayashi, Miho; Matsushima, Yuki; Motoya, Takumi; Sakon, Naomi; Shigemoto, Naoki; Okamoto-Nakagawa, Reiko; Nishimura, Koichi; Yamashita, Yasutaka; Kuroda, Makoto; Saruki, Nobuhiro; Ryo, Akihide; Saraya, Takeshi; Morita, Yukio; Shirabe, Komei; Ishikawa, Mariko; Takahashi, Tomoko; Shinomiya, Hiroto; Okabe, Nobuhiko; Nagasawa, Koo; Suzuki, Yoshiyuki; Katayama, Kazuhiko; Kimura, Hirokazu

    2016-01-01

    Capsid protein of norovirus genogroup II (GII) plays crucial roles in host infection. Although studies on capsid gene evolution have been conducted for a few genotypes of norovirus, the molecular evolution of norovirus GII is not well understood. Here we report the molecular evolution of all GII genotypes, using various bioinformatics techniques. The time-scaled phylogenetic tree showed that the present GII strains diverged from GIV around 1630CE at a high evolutionary rate (around 10−3 substitutions/site/year), resulting in three lineages. The GII capsid gene had large pairwise distances (maximum > 0.39). The effective population sizes of the present GII strains were large (>102) for about 400 years. Positive (20) and negative (over 450) selection sites were estimated. Moreover, some linear and conformational B-cell epitopes were found in the deduced GII capsid protein. These results suggested that norovirus GII strains rapidly evolved with high divergence and adaptation to humans. PMID:27384324

  6. Rapid molecular evolution across amniotes of the IIS/TOR network.

    Science.gov (United States)

    McGaugh, Suzanne E; Bronikowski, Anne M; Kuo, Chih-Horng; Reding, Dawn M; Addis, Elizabeth A; Flagel, Lex E; Janzen, Fredric J; Schwartz, Tonia S

    2015-06-01

    The insulin/insulin-like signaling and target of rapamycin (IIS/TOR) network regulates lifespan and reproduction, as well as metabolic diseases, cancer, and aging. Despite its vital role in health, comparative analyses of IIS/TOR have been limited to invertebrates and mammals. We conducted an extensive evolutionary analysis of the IIS/TOR network across 66 amniotes with 18 newly generated transcriptomes from nonavian reptiles and additional available genomes/transcriptomes. We uncovered rapid and extensive molecular evolution between reptiles (including birds) and mammals: (i) the IIS/TOR network, including the critical nodes insulin receptor substrate (IRS) and phosphatidylinositol 3-kinase (PI3K), exhibit divergent evolutionary rates between reptiles and mammals; (ii) compared with a proxy for the rest of the genome, genes of the IIS/TOR extracellular network exhibit exceptionally fast evolutionary rates; and (iii) signatures of positive selection and coevolution of the extracellular network suggest reptile- and mammal-specific interactions between members of the network. In reptiles, positively selected sites cluster on the binding surfaces of insulin-like growth factor 1 (IGF1), IGF1 receptor (IGF1R), and insulin receptor (INSR); whereas in mammals, positively selected sites clustered on the IGF2 binding surface, suggesting that these hormone-receptor binding affinities are targets of positive selection. Further, contrary to reports that IGF2R binds IGF2 only in marsupial and placental mammals, we found positively selected sites clustered on the hormone binding surface of reptile IGF2R that suggest that IGF2R binds to IGF hormones in diverse taxa and may have evolved in reptiles. These data suggest that key IIS/TOR paralogs have sub- or neofunctionalized between mammals and reptiles and that this network may underlie fundamental life history and physiological differences between these amniote sister clades.

  7. Estimation of oxygen evolution by marine phytoplankton from measurement of the efficiency of Photosystem II electron flow.

    NARCIS (Netherlands)

    Geel, C.; Versluis, W.; Snel, J.F.H.

    1997-01-01

    The relation between photosynthetic oxygen evolution and Photosystem II electron transport was investigated for the marine algae t Phaeodactylum tricornutum, Dunaliella tertiolecta, Tetraselmis sp., t Isochrysis sp. and t Rhodomonas sp.. The rate of Photosystem II electron transport was estimated fr

  8. Fluctuating helical asymmetry and morphology of snails (Gastropoda in divergent microhabitats at 'Evolution Canyons I and II,' Israel.

    Directory of Open Access Journals (Sweden)

    Shmuel Raz

    Full Text Available BACKGROUND: Developmental instability of shelled gastropods is measured as deviations from a perfect equiangular (logarithmic spiral. We studied six species of gastropods at 'Evolution Canyons I and II' in Carmel and the Galilee Mountains, Israel, respectively. The xeric, south-facing, 'African' slopes and the mesic, north-facing, 'European' slopes have dramatically different microclimates and plant communities. Moreover, 'Evolution Canyon II' receives more rainfall than 'Evolution Canyon I.' METHODOLOGY/PRINCIPAL FINDINGS: We examined fluctuating asymmetry, rate of whorl expansion, shell height, and number of rotations of the body suture in six species of terrestrial snails from the two 'Evolution Canyons.' The xeric 'African' slope should be more stressful to land snails than the 'European' slope, and 'Evolution Canyon I' should be more stressful than 'Evolution Canyon II.' Only Eopolita protensa jebusitica showed marginally significant differences in fluctuating helical asymmetry between the two slopes. Contrary to expectations, asymmetry was marginally greater on the 'European' slope. Shells of Levantina spiriplana caesareana at 'Evolution Canyon I,' were smaller and more asymmetric than those at 'Evolution Canyon II.' Moreover, shell height and number of rotations of the suture were greater on the north-facing slopes of both canyons. CONCLUSIONS/SIGNIFICANCE: Our data is consistent with a trade-off between drought resistance and thermoregulation in snails; Levantina was significantly smaller on the 'African' slope, for increasing surface area and thermoregulation, while Eopolita was larger on the 'African' slope, for reducing water evaporation. In addition, 'Evolution Canyon I' was more stressful than Evolution Canyon II' for Levantina.

  9. Evolution of major histocompatibility complex class I and class II genes in the brown bear

    Directory of Open Access Journals (Sweden)

    Kuduk Katarzyna

    2012-10-01

    Full Text Available Abstract Background Major histocompatibility complex (MHC proteins constitute an essential component of the vertebrate immune response, and are coded by the most polymorphic of the vertebrate genes. Here, we investigated sequence variation and evolution of MHC class I and class II DRB, DQA and DQB genes in the brown bear Ursus arctos to characterise the level of polymorphism, estimate the strength of positive selection acting on them, and assess the extent of gene orthology and trans-species polymorphism in Ursidae. Results We found 37 MHC class I, 16 MHC class II DRB, four DQB and two DQA alleles. We confirmed the expression of several loci: three MHC class I, two DRB, two DQB and one DQA. MHC class I also contained two clusters of non-expressed sequences. MHC class I and DRB allele frequencies differed between northern and southern populations of the Scandinavian brown bear. The rate of nonsynonymous substitutions (dN exceeded the rate of synonymous substitutions (dS at putative antigen binding sites of DRB and DQB loci and, marginally significantly, at MHC class I loci. Models of codon evolution supported positive selection at DRB and MHC class I loci. Both MHC class I and MHC class II sequences showed orthology to gene clusters found in the giant panda Ailuropoda melanoleuca. Conclusions Historical positive selection has acted on MHC class I, class II DRB and DQB, but not on the DQA locus. The signal of historical positive selection on the DRB locus was particularly strong, which may be a general feature of caniforms. The presence of MHC class I pseudogenes may indicate faster gene turnover in this class through the birth-and-death process. South–north population structure at MHC loci probably reflects origin of the populations from separate glacial refugia.

  10. World War II, tantalum, and the evolution of modern cranioplasty technique.

    Science.gov (United States)

    Flanigan, Patrick; Kshettry, Varun R; Benzel, Edward C

    2014-04-01

    Cranioplasty is a unique procedure with a rich history. Since ancient times, a diverse array of materials from coconut shells to gold plates has been used for the repair of cranial defects. More recently, World War II greatly increased the demand for cranioplasty procedures and renewed interest in the search for a suitable synthetic material for cranioprostheses. Experimental evidence revealed that tantalum was biologically inert to acid and oxidative stresses. In fact, the observation that tantalum did not absorb acid resulted in the metal being named after Tantalus, the Greek mythological figure who was condemned to a pool of water in the Underworld that would recede when he tried to take a drink. In clinical use, malleability facilitated a single-stage cosmetic repair of cranial defects. Tantalum became the preferred cranioplasty material for more than 1000 procedures performed during World War II. In fact, its use was rapidly adopted in the civilian population. During World War II and the heyday of tantalum cranioplasty, there was a rapid evolution in prosthesis implantation and fixation techniques significantly shaping how cranioplasties are performed today. Several years after the war, acrylic emerged as the cranioplasty material of choice. It had several clear advantages over its metallic counterparts. Titanium, which was less radiopaque and had a more optimal thermal conductivity profile (less thermally conductive), eventually supplanted tantalum as the most common metallic cranioplasty material. While tantalum cranioplasty was popular for only a decade, it represented a significant breakthrough in synthetic cranioplasty. The experiences of wartime neurosurgeons with tantalum cranioplasty played a pivotal role in the evolution of modern cranioplasty techniques and ultimately led to a heightened understanding of the necessary attributes of an ideal synthetic cranioplasty material. Indeed, the history of tantalum cranioplasty serves as a model for innovative

  11. Evolution of the biochemical profile of children treated or undergoing treatment for moderate or severe stunting: consequences of metabolic programming?

    Directory of Open Access Journals (Sweden)

    Jullyana F.R. Alves

    2014-07-01

    Full Text Available OBJECTIVE: to evaluate changes in the biochemical profile of children treated or being treated for moderate or severe stunting in a nutrition recovery and education center. METHODS: this was a retrospective longitudinal study of 263 children treated at this center between August of 2008 to August of 2011, aged 1 to 6 years, diagnosed with moderate (z-score of height-for-age [HAZ] < -2 or severe stunting (HAZ < -3. Data were collected on socioeconomic conditions, dietary habits, and biochemical changes, as well as height according to age. RESULTS: the nutritional intervention showed an increase in HAZ of children with moderate (0.51 ± 0.4, p = 0.001 and severe (0.91 ± 0.7, p = 0.001 stunting during the monitoring. Increased levels of insulin-like growth factor 1 (IGF-1 (initial: 71.7 ng/dL; final: 90.4 ng/dL; p = 0.01 were also observed, as well as a reduction in triglycerides (TG in both severely (initial: 91.8 mg/dL; final: 79.1 mg/dL; p = 0.01 and in moderately malnourished children (initial: 109.2 mg/dL; final 88.7 mg/dL; p = 0.01, and a significant increase in high-density lipoprotein cholesterol HDL-C only in the third year of intervention (initial: 31.4 mg/dL; final: 42.2 mg/dL. The values of total cholesterol (TC and low-density lipoprotein cholesterol (LDL-C levels remained high throughout the treatment (initial: 165.1 mg/dL; final: 163.5 mg/dL and initial: 109.0 mg/dL; final: 107.3 mg/dL, respectively. CONCLUSION: the nutritional treatment for children with short stature was effective in reducing stunting and improving TG and HDL-C after three years of intervention. However, the levels of LDL-C and TC remained high even in treated children. It is therefore speculated that these changes may result from metabolic programming due to malnutrition.

  12. Schedule-selective biochemical modulation of 5-fluorouracil in advanced colorectal cancer – a phase II study

    Directory of Open Access Journals (Sweden)

    Savage Paul

    2002-05-01

    Full Text Available Abstract Background 5-fluorouracil remains the standard therapy for patients with advanced/metastatic colorectal cancer. Pre-clinical studies have demonstrated the biological modulation of 5-fluorouracil by methotrexate and leucovorin. This phase II study was initiated to determine the activity and toxicity of sequential methotrexate – leucovorin and 5-fluorouracil chemotherapy in patients with advanced colorectal cancer. Methods Ninety-seven patients with metastatic colorectal cancer were enrolled onto the study. Methotrexate – 30 mg/m2 was administered every 6 hours for 6 doses followed by a 2 hour infusion of LV – 500 mg/m2. Midway through the leucovorin infusion, patients received 5-fluorouracil – 600 mg/m2. This constituted a cycle of therapy and was repeated every 2 weeks until progression. Results The median age was 64 yrs (34–84 and the Eastern Cooperative Group Oncology performance score was 0 in 37%, 1 in 55% and 2 in 8% of patients. Partial and complete responses were seen in 31% of patients with a median duration of response of 6.4 months. The overall median survival was 13.0 months. The estimated 1-year survival was 53.7%. Grade III and IV toxic effects were modest and included mucositis, nausea and vomiting. Conclusions This phase II study supports previously reported data demonstrating the modest clinical benefit of 5-FU modulation utilizing methotrexate and leucovorin in patients with metastatic colorectal cancer. Ongoing studies evaluating 5-fluorouracil modulation with more novel agents (Irinotecan and/or oxaliplatin are in progress and may prove encouraging.

  13. Measurement of antioxidant activity and antioxidant compounds under versatile extraction conditions: II. The immuno-biochemical antioxidant properties of black sour cherry (Prunus cerasus) extracts.

    Science.gov (United States)

    Haddad, John J; Ghadieh, Rana M; Hasan, Hiba A; Nakhal, Yasmine K; Hanbali, Lama B

    2013-01-01

    Retrospectively, we have measured the antioxidant activity and a variety of antioxidant compounds under versatile extraction conditions of sweet cherry (Prunus avium) extracts. Further in this study, in order to understand the biochemical constituents and antioxidant activities of a variety of extracts of black sour cherries (P. cerasus), a related species, antioxidant compounds, including L-ascorbic acid (vitamin C), phenols, flavonoids, and anthocyanins, and the total antioxidant activity were simultaneously measured under varying extraction conditions (mild heating and brief microwave exposure) for: i) whole juice extracts (WJE), ii) methanol-extracted juice (MEJ), iii) ddH2O-extracted pomace (dPOM), and iv) methanol-extracted pomace (mPOM). The antioxidant activity for WJE was substantially increased with mild and prolonged exposure to either heating or microwave, such that the % inhibition against 2,2-diphenyl-1-bspicrylhydrazyl (DPPH) followed a positive correlation (heating, 5-20 min.; microwave, 1-2 min.), insignificant with MEJ and dPOM, whereas with mPOM there was sharp downregulation. L-Ascorbic acid content was not affected with mild to prolonged heating or microwave exposure (WEJ and mPOM), except a mild increase with MEJ and dPOM. Similarly, total phenols assessed showed no significant variations, as compared with control extracts, except a mild decrease with exposure for mPOM. In a manner similar to L-ascorbic acid, total flavonoid content was increased under varying conditions for WEJ and MEJ, and slightly decreased for dPOM and mPOM. On the other hand, anthocyanins showed differential variations with exposure (up- and downregulation). Assessment of extraction means as compared with WJE revealed sharp increase in the antioxidant activity for MEJ, dPOM and mPOM, significant increase in L-ascorbic acid, total phenol, and flavonoid contents for MEJ, dPOM and mPOM, and mild decrease in anthocyanin contents for MEJ, dPOM, and mPOM. These results

  14. Molecular organization, biochemical function, cellular role and evolution of NfuA, an atypical Fe-S carrier.

    Science.gov (United States)

    Py, Béatrice; Gerez, Catherine; Angelini, Sandra; Planel, Rémy; Vinella, Daniel; Loiseau, Laurent; Talla, Emmanuel; Brochier-Armanet, Céline; Garcia Serres, Ricardo; Latour, Jean-Marc; Ollagnier-de Choudens, Sandrine; Fontecave, Marc; Barras, Frédéric

    2012-10-01

    Biosynthesis of iron-sulphur (Fe-S) proteins is catalysed by multi-protein systems, ISC and SUF. However, 'non-ISC, non-SUF' Fe-S biosynthesis factors have been described, both in prokaryotes and eukaryotes. Here we report in vitro and in vivo investigations of such a 'non-ISC, non SUF' component, the Nfu proteins. Phylogenomic analysis allowed us to define four subfamilies. Escherichia coli NfuA is within subfamily II. Most members of this subfamily have a Nfu domain fused to a 'degenerate' A-type carrier domain (ATC*) lacking Fe-S cluster co-ordinating Cys ligands. The Nfu domain binds a [4Fe-4S] cluster while the ATC* domain interacts with NuoG (a complex I subunit) and aconitase B (AcnB). In vitro, holo-NfuA promotes maturation of AcnB. In vivo, NfuA is necessary for full activity of complex I under aerobic growth conditions, and of AcnB in the presence of superoxide. NfuA receives Fe-S clusters from IscU/HscBA and SufBCD scaffolds and eventually transfers them to the ATCs IscA and SufA. This study provides significant information on one of the Fe-S biogenesis factors that has been often used as a building block by ISC and/or SUF synthesizing organisms, including bacteria, plants and animals.

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

    Science.gov (United States)

    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. PMID:27593466

  16. A prescription and fast code for the long-term evolution of star clusters - II. Unbalanced and core evolution

    NARCIS (Netherlands)

    M. Gieles; P.E.R. Alexander; H.J.G.L.M. Lamers; H. Baumgardt

    2013-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (emacss). The first version (Alexander and Gieles) assumed that cluster evolution is balanced for the majority of the life cycle, meaning that the rate of energy generation in the core of the cluster equals

  17. A prescription and fast code for the long-term evolution of star clusters - II. Unbalanced and core evolution

    NARCIS (Netherlands)

    M. Gieles; P.E.R. Alexander; H.J.G.L.M. Lamers; H. Baumgardt

    2014-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (emacss). The first version (Alexander and Gieles) assumed that cluster evolution is balanced for the majority of the life cycle, meaning that the rate of energy generation in the core of the cluster equals

  18. Speed evolution of CME/shocks using multi-spacecraft observations of type II radio bursts: A case study

    Science.gov (United States)

    Manuel-Hernandez, T.; Aguilar-Rodriguez, E.; Gonzalez-Esparza, J. A.; Ontiveros, V.

    2013-06-01

    We present a study which focuses on the speed evolution of a coronal mass ejection (CME)/shock associated with a type II radio burst observed on January 25, 2007. The type II burst feature had a multi-spacecraft coverage, being detected by the Wind/WAVES and the STEREO/WAVES radio instruments in the frequency range of 14 MHz to 90 kHz. The CME associated with the type II radio burst was observed by the SOHO/LASCO and the STEREO/SECCHI coronographs. Ground-based radio observations of the metric type II burst counterpart were obtained by the Bruny Island Radio Spectrometer (BIRS) in the frequency range of 40 MHz to 25 MHz. We analyzed the combined white-light and radio observations to infer the speed evolution of the CME/shock event. The CME/shock speed from the different data sets shows a significant deceleration near to the Sun followed by a slow and gradual deceleration in the interplanetary medium, which is consistent with the expected evolution of fast CME/shocks. Multi-spacecraft and combined white-light and radio observations are important to gain insight into the tracking of solar transients which propagate in the inner heliosphere.

  19. Rapid Evolution of the Photosystem II Electronic Structure during Water Splitting

    CERN Document Server

    Davis, Katherine M; Palenik, Mark; Yan, Lifen; Purohit, Vatsal; Robison, Gregory; Kosheleva, Irina; Henning, Robert W; Seidler, Gerald T; Pushkar, Yulia

    2015-01-01

    Photosynthetic water oxidation is a fundamental process that sustains the biosphere. A Mn$_{4}$Ca cluster embedded in the photosystem II protein environment is responsible for the production of atmospheric oxygen. Here, time-resolved x-ray emission spectroscopy (XES) was used to observe the process of oxygen formation in real time. These experiments reveal that the oxygen evolution step, initiated by three sequential laser flashes, is accompanied by rapid (within 50 $\\mu$s) changes to the Mn K$\\beta$ XES spectrum. However, no oxidation of the Mn$_{4}$Ca core above the all Mn$^{\\text{IV}}$ state was detected to precede O-O bond formation. A new mechanism featuring Mn$^{\\text{IV}}$=O formation in the S$_{3}$ state is proposed to explain the spectroscopic results. This chemical formulation is consistent with the unique reactivity of the S$_{3}$ state and explains facilitation of the following S$_{3}$ to S$_{0}$ transition, resolving in part the kinetic limitations associated with O-O bond formation. In the propo...

  20. The growth of galactic bulges through mergers in LCDM haloes revisited. II. Morphological mix evolution

    CERN Document Server

    Avila-Reese, Vladimir; Lacerna, Ivan

    2013-01-01

    The mass aggregation and merger histories of present-day distinct haloes selected from the cosmological Millennium Simulations I and II are mapped into stellar mass aggregation and galaxy merger histories of central galaxies by using empirical stellar-to-halo and stellar-to-gas mass relations. The growth of bulges driven by the galaxy mergers/interactions is calculated using analytical recipes. The predicted bulge demographics at redshift z~0 is consistent with observations (Zavala+2012). Here we present the evolution of the morphological mix (traced by the bulge-to-total mass ratio, B/T) as a function of mass up to z=3. This mix remains qualitatively the same up to z~1: B/T0.45 at large masses. At z>1, the fractions of disc-dominated and bulgeless galaxies increase strongly, and by z~2 the era of pure disc galaxies is reached. Bulge-dominated galaxies acquire such a morphology, and most of their mass, following a downsizing trend. Since our results are consistent with several recent observational studies of ...

  1. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy. Evolución bioquímica y respuesta histológica de pacientes con hepatitis C bajo tratamiento antiviral.

    OpenAIRE

    Omar Julián Hernández Ojeda; Marcos Félix Osorio Pagola; Orelvis Martínez Martínez; Denis Monzón Vega; Mabel Vega Galindo

    2011-01-01

    Background: Hepatitis C is a major health problem worldwide and the most common indicator for the need of a liver transplantation in many countries. Objective: To determine the biochemical evolution and the histological response of patients with chronic hepatitis C who were treated with ribavirin and recombinant interferon alfa-

  2. A prescription and fast code for the long-term evolution of star clusters II: unbalanced and core evolution

    CERN Document Server

    Gieles, Mark; Lamers, Henny; Baumgardt, Holger

    2013-01-01

    We introduce version two of the fast star cluster evolution code Evolve Me A Cluster of StarS (EMACSS). The first version (Alexander & Gieles) assumed that cluster evolution is balanced for the majority of the life-cycle, meaning that the rate of energy generation in the core of the cluster equals the diffusion rate of energy by two-body relaxation, which makes the code suitable for modelling clusters in weak tidal fields. In this new version we extend the model to include an unbalanced phase of evolution to describe the pre-collapse evolution and the accompanying escape rate such that clusters in strong tidal fields can also be modelled. We also add a prescription for the evolution of the core radius and density and a related cluster concentration parameter. The model simultaneously solves a series of first-order ordinary differential equations for the rate of change of the core radius, half-mass radius and the number of member stars N. About two thousand integration steps in time are required to solve f...

  3. Precious metals in SDSS quasar spectra. II. Tracking the evolution of strong, 0.4 < z < 2.3 Mg II absorbers with thousands of systems

    Energy Technology Data Exchange (ETDEWEB)

    Seyffert, Eduardo N.; Simcoe, Robert A. [Department of Physics, MIT, 77 Massachusetts Avenue, 37-664D, Cambridge, MA 02139 (United States); Cooksey, Kathy L. [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue, 37-685, Cambridge, MA 02139 (United States); O' Meara, John M. [Department of Chemistry and Physics, Saint Michael' s College, One Winooski Park, Colchester, VT 05439 (United States); Kao, Melodie M. [Caltech, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Prochaska, J. Xavier, E-mail: enseyff@mit.edu, E-mail: simcoe@space.mit.edu, E-mail: kcooksey@space.mit.edu, E-mail: jomeara@smcvt.edu, E-mail: mkao@caltech.edu, E-mail: xavier@ucolick.org [Department of Astronomy and UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2013-12-20

    We have performed an analysis of over 34,000 Mg II doublets at 0.36 < z < 2.29 in Sloan Digital Sky Survey (SDSS) Data Release 7 quasar spectra; the catalog, advanced data products, and tools for analysis are publicly available. The catalog was divided into 14 small redshift bins with roughly 2500 doublets in each and from Monte Carlo simulations, we estimate 50% completeness at rest equivalent width W {sub r} ≈ 0.8 Å. The equivalent width frequency distribution is described well by an exponential model at all redshifts, and the distribution becomes flatter with increasing redshift, i.e., there are more strong systems relative to weak ones. Direct comparison with previous SDSS Mg II surveys reveals that we recover at least 70% of the doublets in these other catalogs, in addition to detecting thousands of new systems. We discuss how these surveys came by their different results, which qualitatively agree but because of the very small uncertainties, differ by a statistically significant amount. The estimated physical cross section of Mg II-absorbing galaxy halos increased approximately threefold from z = 0.4 to z = 2.3, while the W {sub r} ≥ 1 Å absorber line density, dN{sub MgII}/dX, grew by roughly 45%. Finally, we explore the different evolution of various absorber populations—damped Lyα absorbers, Lyman limit systems, strong C IV absorbers, and strong and weaker Mg II systems—across cosmic time (0 < z < 6).

  4. Evolution of stellar collision products in open clusters : II. A grid of low-mass collisions

    NARCIS (Netherlands)

    Glebbeek, E.; Pols, O.R.

    2008-01-01

    In a companion paper we studied the detailed evolution of stellar collision products that occurred in an N-body simulation of the old open cluster M 67 and compared our detailed models to simple prescriptions. In this paper we extend this work by studying the evolution of the collision products in o

  5. Molecular evolution of glutamine synthetase II: Phylogenetic evidence of a non-endosymbiotic gene transfer event early in plant evolution

    Directory of Open Access Journals (Sweden)

    Tartar Aurélien

    2010-06-01

    a cytosolic function. GSIIB sequences were absent in vascular plants where the duplication of GSIIE replaced the function of GSIIB. Conclusions Phylogenetic evidence suggests GSIIB in Chloroplastida evolved by HGT, possibly after the divergence of the primary endosymbiotic lineages. Thus while multiple GS isoenzymes are common among members of the Chloroplastida, the isoenzymes may have evolved via different evolutionary processes. The acquisition of essential enzymes by HGT may provide rapid changes in biochemical capacity and therefore be favored by natural selection.

  6. Evolution of Type II Antifreeze Protein Genes in Teleost Fish: A Complex Scenario Involving Lateral Gene Transfers and Episodic Directional Selection

    OpenAIRE

    Ulf Sorhannus

    2012-01-01

    I examined hypotheses about lateral transfer of type II antifreeze protein (AFP) genes among “distantly” related teleost fish. The effects of episodic directional selection on amino acid evolution were also investigated. The strict consensus results showed that the type II AFP and type II antifreeze-like protein genes were transferred from Osmerus mordax to Clupea harengus, from the ancestral lineage of the Brachyopsis rostratus—Hemitripterus americanus clade to the ancestor of the Hypomesus ...

  7. Temporal Evolution of the Scattering Polarization of the CaII IR Triplet in Hydrodynamical Models of the Solar Chromosphere

    CERN Document Server

    Carlin, E S; Bueno, J Trujillo

    2012-01-01

    Velocity gradients in a stellar atmospheric plasma have an impact on the anisotropy of the radiation field that illuminates each point within the medium, and this may in principle influence the scattering line polarization that results from the induced atomic level polarization. Here we analyze the emergent linear polarization profiles of the Ca II infrared triplet after solving the radiative transfer problem of scattering polarization in time-dependent hydrodynamical models of the solar chromosphere, taking into account the impact of the plasma macroscopic velocity on the atomic level polarization. We discuss the influence that the velocity and temperature shocks in the considered chromospheric models have on the temporal evolution of the scattering polarization signals of the Ca II infrared lines, as well as on the temporally averaged profiles. Our results indicate that the increase of the linear polarization amplitudes caused by macroscopic velocity gradients may be significant in realistic situations. We ...

  8. Comparing equivalent thermal, high pressure and pulsed electric field processes for mild pasteurization of orange juice: Part II: Impact on specific chemical and biochemical quality parameters

    NARCIS (Netherlands)

    Vervoort, L.; Plancken, van der I.; Grauwet, T.; Timmermans, R.A.H.; Mastwijk, H.C.; Matser, A.M.; Hendrickx, M.E.; Loey, van A.

    2011-01-01

    The impact of thermal, high pressure (HP) and pulsed electric field (PEF) processing for mild pasteurization of orange juice was compared on a fair basis, using processing conditions leading to an equivalent degree of microbial inactivation. Examining the effect on specific chemical and biochemical

  9. No severe bottleneck during human evolution: evidence from two apolipoprotein C-II deficiency alleles.

    OpenAIRE

    Xiong, W J; Li, W. H.; Posner, I; Yamamura, T.; Yamamoto, A.; Gotto, A M; Chan, L

    1991-01-01

    The DNA sequences of a Japanese and a Venezuelan apolipoprotein (apo) C-II deficiency allele, of a normal Japanese apo C-II gene, and of a chimpanzee apo C-II gene were amplified by PCR, and their nucleotide sequences were determined on multiple clones of the PCR products. The normal Japanese sequence is identical to--and the chimpanzee sequence differs by only three nucleotides from--a previously published normal Caucasian sequence. In contrast, the two human mutant sequences each differ fro...

  10. Monte Carlo simulations of star clusters - II. Tidally limited, multi-mass systems with stellar evolution

    CERN Document Server

    Giersz, M

    2000-01-01

    A revision of Stod\\{'o}{\\l}kiewicz's Monte Carlo code is used to simulate evolution of large star clusters. A survey of the evolution of N-body systems influenced by the tidal field of a parent galaxy and by stellar evolution is presented. The results presented are in good agreement with theoretical expectations and the results of other methods (Fokker-Planck, Monte Carlo and N-body). The initial rapid mass loss, due to stellar evolution of the most massive stars, causes expansion of the whole cluster and eventually leads to the disruption of less bound systems ($W_0=3$). Models with larger $W_0$ survive this phase of evolution and then undergo core collapse and subsequent post-collapse expansion, like isolated models. The expansion phase is eventually reversed when tidal limitation becomes important. The results presented are the first major step in the direction of simulating evolution of real globular clusters by means of the Monte Carlo method.

  11. The Radio and Optical Luminosity Evolution of Quasars II - The SDSS Sample

    Energy Technology Data Exchange (ETDEWEB)

    Singal, J.; Petrosian, V.; Stawarz, L.; Lawrence, A.

    2012-12-28

    We determine the radio and optical luminosity evolutions and the true distribution of the radio loudness parameter R, defined as the ratio of the radio to optical luminosity, for a set of more than 5000 quasars combining SDSS optical and FIRST radio data. We apply the method of Efron and Petrosian to access the intrinsic distribution parameters, taking into account the truncations and correlations inherent in the data. We find that the population exhibits strong positive evolution with redshift in both wavebands, with somewhat greater radio evolution than optical. With the luminosity evolutions accounted for, we determine the density evolutions and local radio and optical luminosity functions. The intrinsic distribution of the radio loudness parameter R is found to be quite different than the observed one, and is smooth with no evidence of a bi-modality in radio loudness. The results we find are in general agreement with the previous analysis of Singal et al., 2011 which used POSS-I optical and FIRST radio data.

  12. Impact of river overflowing on trace element contamination of volcanic soils in south Italy: Part II. Soil biological and biochemical properties in relation to trace element speciation

    Energy Technology Data Exchange (ETDEWEB)

    D' Ascoli, R. [Dipartimento di Scienze Ambientali, Seconda Universita degli Studi di Napoli, via Vivaldi 43, 81100 Caserta (Italy)]. E-mail: rosaria.dascoli@unina2.it; Rao, M.A. [Dipartimento di Scienze del Suolo, della Pianta e dell' Ambiente, Universita degli Studi di Napoli Federico II, Via Universita 100, 80055 Portici (Italy)]. E-mail: maria.rao@unina.it; Adamo, P. [Dipartimento di Scienze del Suolo, della Pianta e dell' Ambiente, Universita degli Studi di Napoli Federico II, Via Universita 100, 80055 Portici (Italy)]. E-mail: adamo@unina.it; Renella, G. [Dipartimento di Scienza del Suolo e Nutrizione della Pianta, Universita degli Studi di Firenze, P.le delle Cascine 28, 50144 Firenze (Italy)]. E-mail: giancarlo.renella@unifi.it; Landi, L. [Dipartimento di Scienza del Suolo e Nutrizione della Pianta, Universita degli Studi di Firenze, P.le delle Cascine 28, 50144 Firenze (Italy)]. E-mail: loretta.landi@unifi.it; Rutigliano, F.A. [Dipartimento di Scienze Ambientali, Seconda Universita degli Studi di Napoli, via Vivaldi 43, 81100 Caserta (Italy)]. E-mail: floraa.rutigliano@unina2.it; Terribile, F. [Dipartimento di Scienze del Suolo, della Pianta e dell' Ambiente, Universita degli Studi di Napoli Federico II, Via Universita 100, 80055 Portici (Italy)]. E-mail: terribil@unina.it; Gianfreda, L. [Dipartimento di Scienze del Suolo, della Pianta e dell' Ambiente, Universita degli Studi di Napoli Federico II, Via Universita 100, 80055 Portici (Italy)]. E-mail: liliana.gianfreda@unina.it

    2006-11-15

    The effect of heavy metal contamination on biological and biochemical properties of Italian volcanic soils was evaluated in a multidisciplinary study, involving pedoenvironmental, micromorphological, physical, chemical, biological and biochemical analyses. Soils affected by recurring river overflowing, with Cr(III)-contaminated water and sediments, and a non-flooded control soil were analysed for microbial biomass, total and active fungal mycelium, enzyme activities (i.e., FDA hydrolase, dehydrogenase, {beta}-glucosidase, urease, arylsulphatase, acid phosphatase) and bacterial diversity (DGGE characterisation). Biological and biochemical data were related with both total and selected fractions of Cr and Cu (the latter deriving from agricultural chemical products) as well as with total and extractable organic C. The growth and activity of soil microbial community were influenced by soil organic C content rather than Cu or Cr contents. In fact, positive correlations between all studied parameters and organic C content were found. On the contrary, negative correlations were observed only between total fungal mycelium, dehydrogenase, arylsulphatase and acid phosphatase activities and only one Cr fraction (the soluble, exchangeable and carbonate bound). However, total Cr content negatively affected the eubacterial diversity but it did not determine changes in soil activity, probably because of the redundancy of functions within species of soil microbial community. On the other hand, expressing biological and biochemical parameters per unit of total organic C, Cu pollution negatively influenced microbial biomass, fungal mycelium and several enzyme activities, confirming soil organic matter is able to mask the negative effects of Cu on microbial community. - In studied soils organic C content resulted the principal factor influencing growth and activity of microbial community, with Cu and Cr contents having a lower relevance.

  13. The role of OH in the chemical evolution of protoplanetary disks : II. Gas-rich environments

    NARCIS (Netherlands)

    Chaparro-Molano, German; Kamp, I.

    2012-01-01

    Context. We present a method for including gas extinction of cosmic-ray-generated UV photons in chemical models of the midplane of protoplanetary disks, focusing on its implications on ice formation and chemical evolution. Aims. Our goal is to improve on chemical models by treating cosmic rays, the

  14. Evolution of stellar collision products in open clusters. II. A grid of low-mass collisions

    CERN Document Server

    Glebbeek, E

    2008-01-01

    In a companion paper we studied the detailed evolution of stellar collision products that occurred in an $N$-body simulation of the old open cluster M67 and compared our detailed models to simple prescriptions. In this paper we extend this work by studying the evolution of the collision products in open clusters as a function of mass and age of the progenitor stars. We calculated a grid of head-on collisions covering the section of parameter space relevant for collisions in open clusters. We create detailed models of the merger remnants using an entropy-sorting algorithm and follow their subsequent evolution during the initial contraction phase, through the main sequence and up to the giant branch with our detailed stellar evolution code. We compare the location of our models in a colour-magnitude diagram to the observed blue straggler population of the old open clusters M67 and NGC 188 and find that they cover the observed blue straggler region of both clusters. For M67, collisions need to have taken place r...

  15. APPLICATION OF GAS DYNAMICAL FRICTION FOR PLANETESIMALS. II. EVOLUTION OF BINARY PLANETESIMALS

    Energy Technology Data Exchange (ETDEWEB)

    Grishin, Evgeni; Perets, Hagai B. [Physics Department, Technion—Israel Institute of Technology, Haifa, 3200003 (Israel)

    2016-04-01

    One of the first stages of planet formation is the growth of small planetesimals and their accumulation into large planetesimals and planetary embryos. This early stage occurs long before the dispersal of most of the gas from the protoplanetary disk. At this stage gas–planetesimal interactions play a key role in the dynamical evolution of single intermediate-mass planetesimals (m{sub p} ∼ 10{sup 21}–10{sup 25} g) through gas dynamical friction (GDF). A significant fraction of all solar system planetesimals (asteroids and Kuiper-belt objects) are known to be binary planetesimals (BPs). Here, we explore the effects of GDF on the evolution of BPs embedded in a gaseous disk using an N-body code with a fiducial external force accounting for GDF. We find that GDF can induce binary mergers on timescales shorter than the disk lifetime for masses above m{sub p} ≳ 10{sup 22} g at 1 au, independent of the binary initial separation and eccentricity. Such mergers can affect the structure of merger-formed planetesimals, and the GDF-induced binary inspiral can play a role in the evolution of the planetesimal disk. In addition, binaries on eccentric orbits around the star may evolve in the supersonic regime, where the torque reverses and the binary expands, which would enhance the cross section for planetesimal encounters with the binary. Highly inclined binaries with small mass ratios, evolve due to the combined effects of Kozai–Lidov (KL) cycles with GDF which lead to chaotic evolution. Prograde binaries go through semi-regular KL evolution, while retrograde binaries frequently flip their inclination and ∼50% of them are destroyed.

  16. Modes of salmonid MHC class I and II evolution differ from the primate paradigm

    NARCIS (Netherlands)

    Shum, B.P.; Guethlein, L.; Flodin, L.R.; Adkison, M.A.; Hedrick, R.P.; Nehring, R.B.; Stet, R.J.M.; Secombes, C.; Parham, P.

    2001-01-01

    Rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) represent two salmonid genera separated for 15-20 million years. cDNA sequences were determined for the classical MHC class I heavy chain gene UBA and the MHC class II β-chain gene DAB from 15 rainbow and 10 brown trout. Both genes a

  17. Oceanographic profile biochemical measurements collected using a net from the ARLIS II (ARCTIC RESEARCH LABORATORY ICE STATION) in the Arctic in 1964 (NCEI Accession 0000978)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Thirty-nine plankton samples were collected at the Drift Station "Arlis II" at the north of Greenland in the Arctic Ocean during the period from June to December,...

  18. Thermally prepared Ti/RhOx electrodes: II H2 evolution in acid solution

    Directory of Open Access Journals (Sweden)

    Campari Mario

    2002-01-01

    Full Text Available Ti/RhOx electrodes were prepared at 400-600°C by thermal decomposition of Rh chloride. Oxide layers were studied by SEM, cyclic voltammetry and steady-state E-j curves In 0.5 mol dm-3 H2SO4 solution. Voltammetric charge exhibits a maximum at 430°C with fresh electrodes which shifts to 470°C after use for H2 evolution. H2 discharge first produces a decrease in voltammetric charge, then an activation with final settlement to a constant behaviour for "aged" electrodes. H2 evolution on stable RhOx surfaces takes place with 40 mV Tafel slope and a reaction order of 2.5. The fractional reaction order indicates that the surface response to pH is that typical of oxides even for "aged" electrodes. A reaction mechanism is proposed.

  19. Astrocladistics: a phylogenetic analysis of galaxy evolution II. Formation and diversification of galaxies

    CERN Document Server

    Fraix-Burnet, D; Choler, P; Verhamme, A; Fraix-Burnet, Didier; Douzery, Emmanuel J.P.; Choler, Philippe; Verhamme, Anne

    2006-01-01

    This series of papers is intended to evaluate astrocladistics in reconstructing phylogenies of galaxies. The objective of this second paper is to formalize the concept of galaxy formation and to identify the processes of diversification. We show that galaxy diversity can be expected to organize itself in a hierarchy. In order to better understand the role of mergers, we have selected a sample of 43 galaxies from the GALICS database built from simulations with a hybrid model for galaxy formation studies. These simulated galaxies, described by 119 characters and considered as representing still undefined classes, have experienced different numbers of merger events during evolution. Our cladistic analysis yields a robust tree that proves the existence of a hierarchy. Mergers, like interactions (not taken into account in the GALICS simulations), are probably a strong driver for galaxy diversification. Our result shows that mergers participate in a branching type of evolution, but do not seem to play the role of a...

  20. Evolution of two stellar populations in globular clusters II. Effects of primordial gas expulsion

    OpenAIRE

    Decressin, T.; Baumgardt, H.; Charbonnel, C.; Kroupa, P.

    2010-01-01

    We investigate the early evolution of two distinct populations of low-mass stars in globular clusters under the influence of primordial gas expulsion driven by supernovae to study if this process can increase the fraction of second generation stars at the level required by observations. We analyse N-body models that take into account the effect of primordial gas expulsion. We divide the stars into two populations which mimic the chemical and dynamical properties of stars in globular clusters ...

  1. Lagrangian theory of structure formation in relativistic cosmology II: average properties of a generic evolution model

    OpenAIRE

    Buchert, T.; Nayet, C.; Wiegand, A.

    2013-01-01

    Kinematical and dynamical properties of a generic inhomogeneous cosmological model, spatially averaged with respect to free-falling (generalized fundamental) observers, are investigated for the matter model irrotational dust. Paraphrasing a previous Newtonian investigation, we present a relativistic generalization of a backreaction model based on volume-averaging the Relativistic Zeldovich Approximation. In this model we investigate the effect of kinematical backreaction on the evolution of c...

  2. Evolution of binary stars in multiple-population globular clusters - II. Compact binaries

    Science.gov (United States)

    Hong, Jongsuk; Vesperini, Enrico; Sollima, Antonio; McMillan, Stephen L. W.; D'Antona, Franca; D'Ercole, Annibale

    2016-04-01

    We present the results of a survey of N-body simulations aimed at exploring the evolution of compact binaries in multiple-population globular clusters. We show that as a consequence of the initial differences in the structural properties of the first-generation (FG) and the second-generation (SG) populations and the effects of dynamical processes on binary stars, the SG binary fraction decreases more rapidly than that of the FG population. The difference between the FG and SG binary fraction is qualitatively similar to but quantitatively smaller than that found for wider binaries in our previous investigations. The evolution of the radial variation of the binary fraction is driven by the interplay between binary segregation, ionization and ejection. Ionization and ejection counteract in part the effects of mass segregation but for compact binaries the effects of segregation dominate and the inner binary fraction increases during the cluster evolution. We explore the variation of the difference between the FG and the SG binary fraction with the distance from the cluster centre and its dependence on the binary binding energy and cluster structural parameters. The difference between the binary fraction in the FG and the SG populations found in our simulations is consistent with the results of observational studies finding a smaller binary fraction in the SG population.

  3. Evolution of Binary Stars in Multiple-Population Globular Clusters - II. Compact Binaries

    CERN Document Server

    Hong, Jongsuk; Sollima, Antonio; McMillan, Stephen L W; D'Antona, Franca; D'Ercole, Annibale

    2016-01-01

    We present the results of a survey of N-body simulations aimed at exploring the evolution of compact binaries in multiple-population globular clusters.We show that as a consequence of the initial differences in the structural properties of the first-generation (FG) and the second-generation (SG) populations and the effects of dynamical processes on binary stars, the SG binary fraction decreases more rapidly than that of the FG population. The difference between the FG and SG binary fraction is qualitatively similar to but quantitatively smaller than that found for wider binaries in our previous investigations.The evolution of the radial variation of the binary fraction is driven by the interplay between binary segregation, ionization and ejection. Ionization and ejection counteract in part the effects of mass segregation but for compact binaries the effects of segregation dominate and the inner binary fraction increases during the cluster evolution. We explore the variation of the difference between the FG an...

  4. Effects of chloroquine on the adrenocortical function. II. Histological, histochemical and biochemical changes in the suprarenal gland of rats on long-term administration of chloroquine.

    Science.gov (United States)

    Grundmann, M; Bayer, A

    1976-01-01

    White female Wistar rats were used in order to study the influence of long-term oral application of 7-chloro-4-(4-diethylamino-1-methylbutylamino) quinoline (chloroquine) in doses of 30, 40 and 80 mg of base/kg upon the suprarenal gland. Histological, histochemical and biochemical findings give evidence of adrenocortical activation induced by chloroquine at all dose levels tested. The differences between the signs of adrenocortical activation as observed after the various doses were only those of quantity and time onset. The results indicate that the stimulation of the suprarenal cortex produced by repeated administration of chloroquine is not solely a manifestation of toxic action of chloroquine.

  5. ON THE TEMPORAL EVOLUTION OF THE DISK COUNTERPART OF TYPE II SPICULES IN THE QUIET SUN

    Energy Technology Data Exchange (ETDEWEB)

    Sekse, D. H.; Rouppe van der Voort, L. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, N-0315 Oslo (Norway); De Pontieu, B. [Lockheed Martin Solar and Astrophysics Lab, Org. A021S, Bldg. 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

    2013-02-20

    The newly established type II spicule has been speculated to provide enough hot plasma to play an important role in the mass loading and heating of the solar corona. With the identification of rapid blueshifted excursions (RBEs) as the on-disk counterpart of type II spicules we have analyzed three different high-quality timeseries with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish Solar Telescope on La Palma and subjected to an automated detection routine to detect a large number of RBEs for statistical purposes. Our observations are of a quiet-Sun region at disk center and we find lower Doppler velocities, 15-40 km s{sup -1}, and Doppler widths, 2-15 km s{sup -1}, of RBEs than in earlier coronal hole studies, 30-50 km s{sup -1} and 7-23 km s{sup -1}, respectively. In addition, we examine the spatial dependence of Doppler velocities and widths along the RBE axis and conclude that there is no clear trend to this over the field of view or in individual RBEs in the quiet Sun at disk center. These differences with previous coronal hole studies are attributed to the more varying magnetic field configuration in quiet-Sun conditions. Using an extremely high-cadence data set has allowed us to improve greatly on the determination of lifetimes of RBEs, which we find to range from 5 to 60 s with an average lifetime of 30 s, as well as the transverse motions in RBEs, with transverse velocities up to 55 km s{sup -1} and averaging 12 km s{sup -1}. Furthermore, our measurements of the recurrence rates of RBEs provide important new constraints on coronal heating by spicules. We also see many examples of a sinusoidal wave pattern in the transverse motion of RBEs with periods averaging 54 s and amplitudes from 21.5 to 129 km which agrees well with previous studies of wave motion in spicules at the limb. We interpret the appearance of RBEs over their full length within a few seconds as the result of a combination of three kinds of motions as is earlier reported for

  6. Enthalpy-Based Thermal Evolution of Loops: II. Improvements to the Model

    Science.gov (United States)

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

    2011-01-01

    This paper further develops the zero-dimensional (0D) hydrodynamic coronal loop model "Enthalpy-based Thermal Evolution of Loops" (EBTEL) originally proposed by Klimchuk et al (2008), which studies the plasma response to evolving coronal heating. It has typically been applied to impulsive heating events. The basis of EBTEL is the modelling of mass exchange between the corona and transition region and chromosphere in response to heating variations, with the key parameter being the ratio of transition region to coronal radiation. We develop new models for this parameter that now include gravitational stratification and a physically motivated approach to radiative cooling. A number of examples are presented, including nanoflares in short and long loops, and a small flare. It is found that while the evolution of the loop temperature is rather insensitive to the details of the model, accurate tracking of the density requires the inclusion of our new features. In particular, we are able to now obtain highly over-dense loops in the late cooling phase and decreases to the coronal density arising due to stratification. The 0D results are compared to a 1D hydro code (Hydrad). The agreement is acceptable, with the exception of the flare case where some versions of Hydrad can give significantly lower densities. This is attributed to the method used to model the chromosphere in a flare. EBTEL is suitable for general use as a tool for (a) quick-look results of loop evolution in response to a given heating function and (b) situations where the modelling of hundreds or thousands of elemental loops is needed. A single run takes a few seconds on a contemporary laptop.

  7. Time-evolution of quantum systems via a complex nonlinear Riccati equation. II. Dissipative systems

    Science.gov (United States)

    Cruz, Hans; Schuch, Dieter; Castaños, Octavio; Rosas-Ortiz, Oscar

    2016-10-01

    In our former contribution (Cruz et al., 2015), we have shown the sensitivity to the choice of initial conditions in the evolution of Gaussian wave packets via the nonlinear Riccati equation. The formalism developed in the previous work is extended to effective approaches for the description of dissipative quantum systems. By means of simple examples we show the effects of the environment on the quantum uncertainties, correlation function, quantum energy contribution and tunnelling currents. We prove that the environmental parameter γ is strongly related with the sensitivity to the choice of initial conditions.

  8. The Evolution of Criminality in Someş County on the Verge of World War II

    Directory of Open Access Journals (Sweden)

    GEORGE CRISTIAN SPÎNU

    2010-06-01

    Full Text Available This article refers to the characteristics and the evolution of criminality in Someş County, Romania, in 1938. The document supporting the analyses in this article is "Activitatea organelor poliţiei judiciare de sub Autoritatea Inspectoratului de Poliţie al Ţinutului Someş pe anul 1938" (The activity of judicial police bodies subordinated to the Someş County Police Inspectorate Authority in 1938". It contains the crimes recorded by the police authorities that year, along with their attempts at classifying them. With respect to the cases presented, they represent "snapshots" of the criminal events recorded by the police.

  9. Evolution of Prolate Molecular Clouds at Hii Boundaries: II. Formation of BRCs of asymmetrical morphology

    CERN Document Server

    Kinnear, T M; White, G J; Sugitani, K; Goodwin, S

    2015-01-01

    A systematic investigation on the evolution of a prolate cloud at an Hii boundary is conducted using Smoothed Particle Hydrodynamics (SPH) in order to understand the mechanism for a variety of irregular morphological structures found at the boundaries of various Hii regions. The prolate molecular clouds in this investigation are set with their semi-major axes at inclinations between 0 and 90 degrees to a plane parallel ionizing radiation flux. A set of 4 parameters, the number density n, the ratio of major to minor axis gamma, the inclination angle phi and the incident flux F_EUV, are used to define the initial state of the simulated clouds. The dependence of the evolution of a prolate cloud under Radiation Driven Implosion (RDI) on each of the four parameters is investigated. It is found that: i) in addition to the well studied standard type A, B or C Bright Rimmed Clouds (BRCs), many other types such as asymmetrical BRCs, filamentary structures and irregular horse-head structures could also be developed at ...

  10. Introduction: CRevolution 2: origin and evolution of the Colorado River System II

    Science.gov (United States)

    Karlstrom, Karl E.; Beard, L. Sue; House, Kyle; Young, Richard A.; Aslan, Andres; Billingsley, George; Pederson, Joel

    2012-01-01

    A 2010 Colorado River symposium held in Flagstaff, Arizona, in May 2010, had 70 participants who engaged in intense debate about the origin and evolution of the Colorado River system. This symposium, built on two previous decadal scientific meetings, focused on forging scientific consensus where possible, while also articulating continued controversies regarding the Cenozoic evolution of the Colorado River System and the landscapes of the Colorado Plateau–Rocky Mountain region that it drains. New developments involved hypotheses that Neogene mantle flow is driving plateau tilting and differential uplift, with consensus that multidisciplinary studies involving differential incision studies and additional geochronology and thermochronology are needed to test the relative importance of tectonic and geomorphic forcings in shaping the spectacular landscapes of the Colorado Plateau region. In addition to the scientific goals, the meeting participants emphasized the iconic status of Grand Canyon for geosciences, and the importance of good communication between the research community, the geoscience education/interpretation community, the public, and the media. Building on a century-long tradition, this region still provides a globally important natural laboratory for studies of the interactions of erosion and tectonism in the shaping landscape of elevated plateaus.

  11. Spectral Energy Distributions of Type 1 AGN in XMM-COSMOS Survey II - Shape Evolution

    CERN Document Server

    Hao, Heng; Civano, Francesca; Zamorani, Gianni; Ho, Luis C; Comastri, Andrea; Bongiorno, Angela; Merloni, Andrea; Brusa, Marcella; Trump, Jonathan R; Salvato, Mara; Impey, Chris D; Koekemoer, Anton M; Lanzuisi, Giorgio; Celotti, Annalisa; Jahnke, Knud; Vignali, Cristian; Silverman, John D; Urry, C Megan; Schawinski, Kevin; Capak, Peter

    2012-01-01

    The near-infrared to optical-ultraviolet (0.1 -- 10 $\\mu m$) spectral energy distribution (SED) shapes of 407 X-ray-selected radio-quiet type 1 AGN in the wide-field "Cosmic Evolution Survey" (COSMOS) have been studied for signs of evolution. For a sub-sample of 200 radio-quiet quasars with black hole mass estimation and host galaxy correction, we study the mean SEDs as a function of a broad range of redshift, bolometric luminosity, black hole mass and Eddington ratio, and compare them with the Elvis et al. (1994, E94) type 1 AGN mean SED. The mean SEDs in each bin are very similar to each other, showing no evidence of dependence on any of the analyzed parameters. We also checked the SED dispersion as a function of these four parameters, and found no significant dependance. The dispersion of the XMM-COSMOS SEDs is generally larger than E94 SED dispersion in the ultraviolet, which might be largely due to the broader "window function" for COSMOS quasars, and the X-ray based selection technique.

  12. Enthalpy-based Thermal Evolution of Loops: II. Improvements to the Model

    CERN Document Server

    Cargill, Peter J; Klimchuk, James A

    2012-01-01

    This paper develops the zero-dimensional (0D) hydrodynamic coronal loop model "Enthalpy-based Thermal Evolution of Loops" (EBTEL) proposed by Klimchuk et al (2008), which studies the plasma response to evolving coronal heating, especially impulsive heating events. The basis of EBTEL is the modelling of mass exchange between the corona and transition region and chromosphere in response to heating variations, with the key parameter being the ratio of transition region to coronal radiation. We develop new models for this parameter that now include gravitational stratification and a physically motivated approach to radiative cooling. A number of examples are presented, including nanoflares in short and long loops, and a small flare. The new features in EBTEL are important for accurate tracking of, in particular, the density. The 0D results are compared to a 1D hydro code (Hydrad) with generally good agreement. EBTEL is suitable for general use as a tool for (a) quick-look results of loop evolution in response to ...

  13. Improved angular momentum evolution model for solar-like stars II. Exploring the mass dependence

    CERN Document Server

    Gallet, Florian

    2015-01-01

    We developed angular momentum evolution models for 0.5 and 0.8 $M_{\\odot}$ stars. The parametric models include a new wind braking law based on recent numerical simulations of magnetised stellar winds, specific dynamo and mass-loss rate prescriptions, as well as core/envelope decoupling. We compare model predictions to the distributions of rotational periods measured for low mass stars belonging to star forming regions and young open clusters. Furthermore, we explore the mass dependence of model parameters by comparing these new models to the solar-mass models we developed earlier. Rotational evolution models are computed for slow, median, and fast rotators at each stellar mass. The models reproduce reasonably well the rotational behaviour of low-mass stars between 1~Myr and 8-10~Gyr, including pre-main sequence to zero-age main sequence spin up, prompt zero-age main sequence spin down, and early-main sequence convergence of the surface rotation rates. Fast rotators are found to have systematically shorter di...

  14. Chemical evolution in the early phases of massive star formation II: Deuteration

    CERN Document Server

    Gerner, Th; Beuther, H; Semenov, D; Linz, H; Abertsson, T; Henning, Th

    2015-01-01

    The chemical evolution in high-mass star-forming regions is still poorly constrained. Studying the evolution of deuterated molecules allows to differentiate between subsequent stages of high-mass star formation regions due to the strong temperature dependence of deuterium isotopic fractionation. We observed a sample of 59 sources including 19 infrared dark clouds, 20 high-mass protostellar objects, 11 hot molecular cores and 9 ultra-compact HII regions in the (3-2) transitions of the four deuterated molecules, DCN, DNC, DCO+ and N2D+ as well as their non-deuterated counterpart. The overall detection fraction of DCN, DNC and DCO+ is high and exceeds 50% for most of the stages. N2D+ was only detected in a few infrared dark clouds and high-mass protostellar objects. It can be related to problems in the bandpass at the frequency of the transition and to low abundances in the more evolved, warmer stages. We find median D/H ratios of ~0.02 for DCN, ~0.005 for DNC, ~0.0025 for DCO+ and ~0.02 for N2D+. While the D/H ...

  15. Application of Gas Dynamical Friction for Planetesimals: II. Evolution of Binary Planetesimals

    CERN Document Server

    Grishin, Evgeni

    2015-01-01

    One of first the stages of planet formation is the growth of small planetesimals and their accumulation into large planetesimals and planetary embryos. This early stage occurs much before the dispersal of most of the gas from the protoplanetary disk. At this stage gas-planetesimal interactions play a key role in the dynamical evolution of \\emph{single} intermediate-mass planetesimals ($m_{p}\\sim10^{21}-10^{25}g$) \\emph{through gas dynamical friction} (GDF). A significant fraction of all Solar system planetesimals (asteroids and Kuiper-belt objects) are known to be binary planetesimals (BPs). Here, we explore the effects of GDF on the evolution of \\emph{binary} planetesimals embedded in a gaseous disk using an N-body code with a fiducial external force accounting for GDF. We find that GDF can induce binary mergers on timescales shorter than the disk lifetime for masses above $m_{p}\\gtrsim10^{22}g$ at 1AU, independent of the binary initial separation and eccentricity. Such mergers can affect the structure of me...

  16. TiO2/ZnS/CdS Nanocomposite for Hydrogen Evolution and Orange II Dye Degradation

    Directory of Open Access Journals (Sweden)

    Václav Štengl

    2011-01-01

    Full Text Available TiO2/ZnS/CdS composites for photocatalytic hydrogen production from water were prepared by homogeneous hydrolysis of aqueous solutions mixture of TiOSO4, ZnSO4, and CdSO4 with thioacetamide. Hydrogen evolution was observed in the presence of palladium and platinum nanoparticles deposited on TiO2/ZnS/CdS composites. The morphology was obtained by scanning electron microscopy, the nitrogen adsorption-desorption was used for determination of surface area (BET and porosity. The method of UV-VIS diffuse reflectance spectroscopy was employed to estimate band-gap energies of prepared TiO2/ZnS/CdS nano-composites. The photocatalytic activity of the prepared samples were assessed by photocatalytic decomposition of Orange II dye in an aqueous slurry under UV irradiation at 365 nm wavelength and visible light up to 400 nm wavelength. Doped titanium dioxide by the CdS increased band-gap energy and doping with ZnS increased photocatalytic activity. The best photocatalytic activity for H2 evolution shows sample named TiZnCd7 on surface deposited with palladium, which contains 20.21% TiO2, 78.5% ZnS, and 1.29% CdS.

  17. Atomic data for Zn II - Improving Spectral Diagnostics of Chemical Evolution in High-redshift Galaxies

    CERN Document Server

    Kisielius, Romas; Ferland, Gary J; Bogdanovich, Pavel; Som, Debopam; Lykins, Matt L

    2015-01-01

    Damped Lyman-alpha (DLA) and sub-DLA absorbers in quasar spectra provide the most sensitive tools for measuring element abundances of distant galaxies. Estimation of abundances from absorption lines depends sensitively on the accuracy of the atomic data used. We have started a project to produce new atomic spectroscopic parameters for optical/UV spectral lines using state-of-the-art computer codes employing very broad configuration interaction basis. Here we report our results for Zn II, an ion used widely in studies of the interstellar medium (ISM) as well as DLA/sub-DLAs. We report new calculations of many energy levels of Zn II, and the line strengths of the resulting radiative transitions. Our calculations use the configuration interaction approach within a numerical Hartree-Fock framework. We use both non-relativistic and quasi-relativistic one-electron radial orbitals. We have incorporated the results of these atomic calculations into the plasma simulation code Cloudy, and applied them to a lab plasma a...

  18. Atomic data for S II - Toward Better Diagnostics of Chemical Evolution in High-redshift Galaxies

    CERN Document Server

    Kisielius, Romas; Ferland, Gary J; Bogdanovich, Pavel; Lykins, Matt L

    2013-01-01

    Absorption-line spectroscopy is a powerful tool used to estimate element abundances in the nearby as well as distant universe. The accuracy of the abundances thus derived is, naturally, limited by the accuracy of the atomic data assumed for the spectral lines. We have recently started a project to perform the new extensive atomic data calculations used for optical/UV spectral lines in the plasma modeling code Cloudy using state-of-the-art quantal calculations. Here we demonstrate our approach by focussing on S II, an ion used to estimate metallicities for Milky Way interstellar clouds as well as distant damped Lyman-alpha (DLA) and sub-DLA absorber galaxies detected in the spectra of quasars and gamma-ray bursts (GRBs). We report new extensive calculations of a large number of energy levels of S II, and the line strengths of the resulting radiative transitions. Our calculations are based on the configuration interaction approach within a numerical Hartree-Fock framework, and utilize both non-ralativistic and ...

  19. Rapid evolution in response to introduced predators II: the contribution of adaptive plasticity

    Directory of Open Access Journals (Sweden)

    Knapp Roland A

    2007-02-01

    Full Text Available Abstract Background Introductions of non-native species can significantly alter the selective environment for populations of native species, which can respond through phenotypic plasticity or genetic adaptation. We examined phenotypic and genetic responses of Daphnia populations to recent introductions of non-native fish to assess the relative roles of phenotypic plasticity versus genetic change in causing the observed patterns. The Daphnia community in alpine lakes throughout the Sierra Nevada of California (USA is ideally suited for investigation of rapid adaptive evolution because there are multiple lakes with and without introduced fish predators. We conducted common-garden experiments involving presence or absence of chemical cues produced by fish and measured morphological and life-history traits in Daphnia melanica populations collected from lakes with contrasting fish stocking histories. The experiment allowed us to assess the degree of population differentiation due to fish predation and examine the contribution of adaptive plasticity in the response to predator introduction. Results Our results show reductions in egg number and body size of D. melanica in response to introduced fish. These phenotypic changes have a genetic basis but are partly due to a direct response to chemical cues from fish via adaptive phenotypic plasticity. Body size showed the largest phenotypic change, on the order of nine phenotypic standard deviations, with approximately 11% of the change explained by adaptive plasticity. Both evolutionary and plastic changes in body size and egg number occurred but no changes in the timing of reproduction were observed. Conclusion Native Daphnia populations exposed to chemical cues produced by salmonid fish predators display adaptive plasticity for body size and fecundity. The magnitude of adaptive plasticity was insufficient to explain the total phenotypic change, so the realized change in phenotypic means in populations

  20. Evolution of self-gravitating magnetized disks. II- Interaction between MHD turbulence and gravitational instabilities

    CERN Document Server

    Fromang, S; Terquem, C; De Villiers, J P; Fromang, Sebastien; Balbus, Steven A.; Terquem, Caroline; Villiers, Jean-Pierre De

    2004-01-01

    We present 3D magnetohydrodynamic (MHD) numerical simulations of the evolution of self--gravitating and weakly magnetized disks with an adiabatic equation of state. Such disks are subject to the development of both the magnetorotational and gravitational instabilities, which transport angular momentum outward. As in previous studies, our hydrodynamical simulations show the growth of strong m=2 spiral structure. This spiral disturbance drives matter toward the central object and disappears when the Toomre parameter Q has increased well above unity. When a weak magnetic field is present as well, the magnetorotational instability grows and leads to turbulence. In that case, the strength of the gravitational stress tensor is lowered by a factor of about~2 compared to the hydrodynamical run and oscillates periodically, reaching very small values at its minimum. We attribute this behavior to the presence of a second spiral mode with higher pattern speed than the one which dominates in the hydrodynamical simulations...

  1. Lagrangian theory of structure formation in relativistic cosmology II: average properties of a generic evolution model

    CERN Document Server

    Buchert, Thomas; Wiegand, Alexander

    2013-01-01

    Kinematical and dynamical properties of a generic inhomogeneous cosmological model, spatially averaged with respect to free-falling (generalized fundamental) observers, are investigated for the matter model `irrotational dust'. Paraphrasing a previous Newtonian investigation, we present a relativistic generalization of a backreaction model based on volume-averaging the `Relativistic Zel'dovich Approximation'. In this model we investigate the effect of `kinematical backreaction' on the evolution of cosmological parameters as they are defined in an averaged inhomogenous cosmology, and we show that the backreaction model interpolates between orthogonal symmetry properties by covering subcases of the plane-symmetric solution, the Lemaitre-Tolman-Bondi solution and the Szekeres solution. We so obtain a powerful model that lays the foundations for quantitatively addressing curvature inhomogeneities as they would be interpreted as `Dark Energy' or `Dark Matter' in a quasi-Newtonian cosmology. The present model, havi...

  2. Genetic structure and evolution of the Vps25 family, a yeast ESCRT-II component

    Directory of Open Access Journals (Sweden)

    Slater Ruth

    2006-08-01

    Full Text Available Abstract Background Vps25p is the product of yeast gene VPS25 and is found in an endosomal sorting complex required for transport (ESCRT-II, along with Vps22p and Vps36p. This complex is essential for sorting of ubiquitinated biosynthetic and endosomal cargoes into endosomes. Results We found that VPS25 is a highly conserved and widely expressed eukaryotic gene, with single orthologs in chromalveolate, excavate, amoebozoan, plant, fungal and metazoan species. Two paralogs were found in Trichomonas vaginalis. An ortholog was strikingly absent from the Encephalitozoon cuniculi genome. Intron positions were analyzed in VPS25 from 36 species. We found evidence for five ancestral VPS25 introns, intron loss, and single instances of intron gain (a Paramecium species and intron slippage (Theileria species. Processed pseudogenes were identified in four mammalian genomes, with a notable absence in the mouse genome. Two retropseudogenes were found in the chimpanzee genome, one more recently inserted, and one evolving from a common primate ancestor. The amino acid sequences of 119 Vps25 orthologs are aligned, compared with the known secondary structure of yeast Vps25p, and used to carry out phylogenetic analysis. Residues in two amino-terminal PPXY motifs (motif I and II, involved in dimerization of Vps25p and interaction with Vps22p and Vps36p, were closely, but not absolutely conserved. Specifically, motif I was absent in Vps25 homologs of chromalveolates, euglenozoa, and diplomonads. A highly conserved carboxy-terminal lysine was identified, which suggests Vps25 is ubiquitinated. Arginine-83 of yeast Vps25p involved in Vps22p interaction was highly, but not absolutely, conserved. Human tissue expression analysis showed universal expression. Conclusion We have identified 119 orthologs of yeast Vps25p. Expression of mammalian VPS25 in a wide range of tissues, and the presence in a broad range of eukaryotic species, indicates a basic role in eukaryotic cell

  3. Compact planetary systems perturbed by an inclined companion. II. Stellar spin-orbit evolution

    International Nuclear Information System (INIS)

    The stellar spin orientation relative to the orbital planes of multiplanet systems is becoming accessible to observations. Here, we analyze and classify different types of spin-orbit evolution in compact multiplanet systems perturbed by an inclined outer companion. Our study is based on classical secular theory, using a vectorial approach developed in a separate paper. When planet-planet perturbations are truncated at the second order in eccentricity and mutual inclination, and the planet-companion perturbations are developed at the quadrupole order, the problem becomes integrable. The motion is composed of a uniform precession of the whole system around the total angular momentum, and in the rotating frame, the evolution is periodic. Here, we focus on the relative motion associated with the oscillations of the inclination between the planet system and the outer orbit and of the obliquities of the star with respect to the two orbital planes. The solution is obtained using a powerful geometric method. With this technique, we identify four different regimes characterized by the nutation amplitude of the stellar spin axis relative to the orbital plane of the planets. In particular, the obliquity of the star reaches its maximum when the system is in the Cassini regime where planets have more angular momentum than the star and where the precession rate of the star is similar to that of the planets induced by the companion. In that case, spin-orbit oscillations exceed twice the inclination between the planets and the companion. Even if the mutual inclination is only ≅ 20°, this resonant case can cause the spin-orbit angle to oscillate between perfectly aligned and retrograde values.

  4. Evolution of Compact Binary Populations in Globular Clusters: A Boltzmann Study. II. Introducing Stochasticity

    Science.gov (United States)

    Banerjee, Sambaran; Ghosh, Pranab

    2008-06-01

    We continue the exploration that we began in Paper I of using the Boltzmann scheme to study the evolution of compact binary populations of globular clusters, introducing in this paper our method of handling the stochasticity inherent in the dynamical processes of binary formation, destruction, and hardening in globular clusters. We describe these stochastic processes as "Wiener processes," whereupon the Boltzmann equation becomes a stochastic partial differential equation, the solution of which involves the use of "Itō calculus" (this use being the first, to our knowledge, in this subject), in addition to ordinary calculus. As in Paper I, we focus on the evolution of (1) the number of X-ray binaries NXB in globular clusters and (2) the orbital period distribution of these binaries. We show that, although the details of the fluctuations in the above quantities differ from one "realization" to another of the stochastic processes, the general trends follow those found in the continuous-limit study of Paper I, and the average result over many such realizations is very close to the continuous-limit result. We investigate the dependence of NXB found by these calculations on two essential globular cluster properties, namely, the star-star and star-binary encounter rate parameters Γ and γ, for which we coined the name "Verbunt parameters" in Paper I. We compare our computed results with those from Chandra observations of Galactic globular clusters, showing that the expected scalings of NXB with the Verbunt parameters are in good agreement with those observed. We indicate additional features that can be incorporated into the scheme in the future, as well as how more elaborate problems can be tackled.

  5. Compact planetary systems perturbed by an inclined companion. II. Stellar spin-orbit evolution

    Energy Technology Data Exchange (ETDEWEB)

    Boué, Gwenaël; Fabrycky, Daniel C., E-mail: boue@imcce.fr [Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)

    2014-07-10

    The stellar spin orientation relative to the orbital planes of multiplanet systems is becoming accessible to observations. Here, we analyze and classify different types of spin-orbit evolution in compact multiplanet systems perturbed by an inclined outer companion. Our study is based on classical secular theory, using a vectorial approach developed in a separate paper. When planet-planet perturbations are truncated at the second order in eccentricity and mutual inclination, and the planet-companion perturbations are developed at the quadrupole order, the problem becomes integrable. The motion is composed of a uniform precession of the whole system around the total angular momentum, and in the rotating frame, the evolution is periodic. Here, we focus on the relative motion associated with the oscillations of the inclination between the planet system and the outer orbit and of the obliquities of the star with respect to the two orbital planes. The solution is obtained using a powerful geometric method. With this technique, we identify four different regimes characterized by the nutation amplitude of the stellar spin axis relative to the orbital plane of the planets. In particular, the obliquity of the star reaches its maximum when the system is in the Cassini regime where planets have more angular momentum than the star and where the precession rate of the star is similar to that of the planets induced by the companion. In that case, spin-orbit oscillations exceed twice the inclination between the planets and the companion. Even if the mutual inclination is only ≅ 20°, this resonant case can cause the spin-orbit angle to oscillate between perfectly aligned and retrograde values.

  6. Patterns of evolution of MHC class II genes of crows (Corvus suggest trans-species polymorphism

    Directory of Open Access Journals (Sweden)

    John A. Eimes

    2015-03-01

    Full Text Available A distinguishing characteristic of genes that code for the major histocompatibility complex (MHC is that alleles often share more similarity between, rather than within species. There are two likely mechanisms that can explain this pattern: convergent evolution and trans-species polymorphism (TSP, in which ancient allelic lineages are maintained by balancing selection and retained by descendant species. Distinguishing between these two mechanisms has major implications in how we view adaptation of immune genes. In this study we analyzed exon 2 of the MHC class IIB in three passerine bird species in the genus Corvus: jungle crows (Corvus macrorhynchos japonensis American crows (C. brachyrhynchos and carrion crows (C. corone orientalis. Carrion crows and American crows are recently diverged, but allopatric, sister species, whereas carrion crows and jungle crows are more distantly related but sympatric species, and possibly share pathogens linked to MHC IIB polymorphisms. These patterns of evolutionary divergence and current geographic ranges enabled us to test for trans-species polymorphism and convergent evolution of the MHC IIB in crows. Phylogenetic reconstructions of MHC IIB sequences revealed several well supported interspecific clusters containing all three species, and there was no biased clustering of variants among the sympatric carrion crows and jungle crows. The topologies of phylogenetic trees constructed from putatively selected sites were remarkably different than those constructed from putatively neutral sites. In addition, trees constructed using non-synonymous substitutions from a continuous fragment of exon 2 had more, and generally more inclusive, supported interspecific MHC IIB variant clusters than those constructed from the same fragment using synonymous substitutions. These phylogenetic patterns suggest that recombination, especially gene conversion, has partially erased the signal of allelic ancestry in these species. While

  7. Confronting uncertainties in stellar physics II. exploring differences in main-sequence stellar evolution tracks

    CERN Document Server

    Stancliffe, R J; Passy, J -C; Schneider, F R N

    2016-01-01

    We assess the systematic uncertainties in stellar evolutionary calculations for low- to intermediate-mass, main-sequence stars. We compare published stellar tracks from several different evolution codes with our own tracks computed using the stellar codes STARS and MESA. In particular, we focus on tracks of 1 and 3 solar masses at solar metallicity. We find that the spread in the available 1 solar mass tracks (computed before the recent solar composition revision by Asplund et al.) can be covered by tracks between 0.97-1.01 solar masses computed with the STARS code. We assess some possible causes of the origin of this uncertainty, including how the choice of input physics and the solar constraints used to perform the solar calibration affect the tracks. We find that for a 1 solar mass track, uncertainties of around 10% in the initial hydrogen abundance and initial metallicity produce around a 2% error in mass. For the 3 solar mass tracks, there is very little difference between the tracks from the various dif...

  8. Dual black holes in merger remnants. II: spin evolution and gravitational recoil

    CERN Document Server

    Dotti, M; Perego, A; Colpi, M; Ruszkowski, M; Haardt, F

    2009-01-01

    Using high resolution hydrodynamical simulations, we explore the spin evolution of massive dual black holes orbiting inside a circumnuclear disc, relic of a gas-rich galaxy merger. The black holes spiral inwards from initially eccentric co or counter-rotating coplanar orbits relative to the disc's rotation, and accrete gas that is carrying a net angular momentum. As the black hole mass grows, its spin changes in strength and direction due to its gravito-magnetic coupling with the small-scale accretion disc. We find that the black hole spins loose memory of their initial orientation, as accretion torques suffice to align the spins with the angular momentum of their orbit on a short timescale (<1-2 Myr). A residual off-set in the spin direction relative to the orbital angular momentum remains, at the level of <10 degrees for the case of a cold disc, and <30 degrees for a warmer disc. Alignment in a cooler disc is more effective due to the higher coherence of the accretion flow near each black hole that...

  9. The longterm evolution of neutron star merger remnants II: radioactively powered transients

    CERN Document Server

    Grossman, Doron; Rosswog, Stephan; Piran, Tsvi

    2013-01-01

    We use 3D hydrodynamic simulations of the longterm evolution of neutron star merger ejecta to predict the light curves of electromagnetic transients that are powered by the decay of freshly produced r-process nuclei. For the dynamic ejecta that are launched by tidal and hydrodynamic interaction we adopt gray opacities of 10 cm$^2$/g, as suggested by recent studies. For our reference case of a 1.3-1.4 $m_\\odot$ merger we find a broad IR peak 2-4 days after the merger. The peak luminosity is $\\approx 2\\times 10^{40}$ erg/s for an average orientation, but increased by up to a factor of 4 for more favorable binary parameters and viewing angles. These signals are rather weak and hardly detectable within the large error box (~100 deg$^2$) of a GW trigger. A second electromagnetic transient results from neutrino-driven winds. These winds produce "weak" r-process material with 50

  10. Stellar Rotation in Young Clusters. II. Evolution of Stellar Rotation and Surface Helium Abundance

    CERN Document Server

    Huang, W

    2005-01-01

    We derive the effective temperatures and gravities of 461 OB stars in 19 young clusters by fitting the H-gamma profile in their spectra. We use synthetic model profiles for rotating stars to develop a method to estimate the polar gravity for these stars, which we argue is a useful indicator of their evolutionary status. We combine these results with projected rotational velocity measurements obtained in a previous paper on these same open clusters. We find that the more massive B-stars experience a spin down as predicted by the theories for the evolution of rotating stars. Furthermore, we find that the members of binary stars also experience a marked spin down with advanced evolutionary state due to tidal interactions. We also derive non-LTE-corrected helium abundances for most of the sample by fitting the He I 4026, 4387, 4471 lines. A large number of helium peculiar stars are found among cooler stars with Teff < 23000 K. The analysis of the high mass stars (8.5 solar masses < M < 16 solar masses) s...

  11. Spin flips - II. Evolution of dark matter halo spin orientation, and its correlation with major mergers

    Science.gov (United States)

    Bett, Philip E.; Frenk, Carlos S.

    2016-09-01

    We expand our previous study on the relationship between changes in the orientation of the angular momentum vector of dark matter haloes (`spin flips') and changes in their mass, to cover the full range of halo masses in a simulation cube of length 100 h-1 Mpc. Since strong disturbances to a halo (such as might be indicated by a large change in the spin direction) are likely also to disturb the galaxy evolving within, spin flips could be a mechanism for galaxy morphological transformation without involving major mergers. We find that 35 per cent of haloes have, at some point in their lifetimes, had a spin flip of at least 45° that does not coincide with a major merger. Over 75 per cent of large spin flips coincide with non-major mergers; only a quarter coincide with major mergers. We find a similar picture for changes to the inner halo spin orientation, although here there is an increased likelihood of a flip occurring. Changes in halo angular momentum orientation, and other such measures of halo perturbation, are therefore very important quantities to consider, in addition to halo mergers, when modelling the formation and evolution of galaxies and confronting such models with observations.

  12. The role of OH in the chemical evolution of protoplanetary disks II. Gas-rich environments

    CERN Document Server

    Molano, Germán Chaparro

    2012-01-01

    Context. We present a method for including gas extinction of cosmic-ray-generated UV photons in chemical models of the midplane of protoplanetary disks, focusing on its implications on ice formation and chemical evolution. Aims. Our goal is to improve on chemical models by treating cosmic rays, the main source of ionization in the midplane of the disk, in a way that is consistent with current knowledge of the gas and grain environment present in those regions. We trace the effects of cosmic rays by identifying the main chemical reaction channels and also the main contributors to the gas opacity to cosmic-ray-induced UV photons. This information is crucial in implementing gas opacities for cosmic-ray-induced reactions in full 2D protoplanetary disk models. Methods. We considered time-dependent chemical models within the range 1-10 AU in the midplane of a T Tauri disk. The extinction of cosmic-ray-induced UV photons by gaseous species was included in the calculation of photorates at each timestep. We integrated...

  13. On the evolution of the snow line in protoplanetary discs II: Analytic approximations

    CERN Document Server

    Martin, Rebecca G

    2013-01-01

    We examine the evolution of the snow line in a protoplanetary disc that contains a dead zone (a region of zero or low turbulence). The snow line is within a self-gravitating part of the dead zone, and we obtain a fully analytic solution for its radius. Our formula could prove useful for future observational attempts to characterise the demographics of planets outside the snow line. External sources such as comic rays or X-rays from the central star can ionise the disc surface layers and allow the magneto-rotational instability to drive turbulence there. We show that provided that the surface density in this layer is less than about 50 g/cm^2, the dead zone solution exists, after an initial outbursting phase, until the disc is dispersed by photoevaporation. We demonstrate that the snow line radius is significantly larger than that predicted by a fully turbulent disc model, and that in our own solar system it remains outside of the orbital radius of the Earth. Thus, the inclusion of a dead zone into a protoplan...

  14. The Bar-Halo Interaction - II. Secular evolution and the religion of N-body simulations

    CERN Document Server

    Weinberg, M D; Katz, Neal; Weinberg, Martin D.

    2006-01-01

    This paper explores resonance-driven secular evolution between a bar and dark-matter halo using N-body simulations. We make direct comparisons to our analytic theory (Weinberg & Katz 2005) to demonstrate the great difficulty that an N-body simulation has representing these dynamics for realistic astronomical interactions. In a dark-matter halo, the bar's angular momentum is coupled to the central density cusp (if present) by the Inner Lindblad Resonance. Owing to this angular momentum transfer and self-consistent re-equilibration, strong realistic bars WILL modify the cusp profile, lowering the central densities within about 30% of the bar radius in a few bar orbits. Past results to the contrary (Sellwood 2006, McMillan & Dehnen 2005) may be the result of weak bars or numerical artifacts. The magnitude depends on many factors and we illustrate the sensitivity of the response to the dark-matter profile, the bar shape and mass, and the galaxy's evolutionary history. For example, if the bar length is com...

  15. Spin Evolution of Accreting Young Stars. II. Effect of Accretion-Powered Stellar Winds

    CERN Document Server

    Matt, Sean P; Greene, Thomas P; Pudritz, Ralph E

    2011-01-01

    We present a model for the rotational evolution of a young, solar-mass star interacting magnetically with an accretion disk. As in a previous paper (Paper I), the model includes changes in the star's mass and radius as it descends the Hayashi track, a decreasing accretion rate, and a prescription for the angular momentum transfer between the star and disk. Paper I concluded that, for the relatively strong magnetic coupling expected in real systems, additional processes are necessary to explain the existence of slowly rotating pre-main-sequence stars. In the present paper, we extend the stellar spin model to include the effect of a spin-down torque that arises from an accretion-powered stellar wind. For a range of magnetic field strengths, accretion rates, initial spin rates, and mass outflow rates, the modeled stars exhibit rotation periods within the range of 1--10 days in the age range of 1--3 Myr. This range coincides with the bulk of the observed rotation periods, with the slow rotators corresponding to s...

  16. Anthocyanins and Their Variation in Red Wines II. Anthocyanin Derived Pigments and Their Color Evolution

    Directory of Open Access Journals (Sweden)

    Chang-Qing Duan

    2012-02-01

    Full Text Available Originating in the grapes, anthocyanins and their derivatives are the crucial pigments responsible for the red wine color. During wine maturation and aging, the concentration of monomeric anthocyanins declines constantly, while numerous more complex and stable anthocyanin derived pigments are formed, mainly including pyranoanthocyanins, polymeric anthocyanins produced from condensation between anthocyanin and/or flavan-3-ols directly or mediated by aldehydes. Correspondingly, their structural modifications result in a characteristic variation of color, from purple-red color in young red wines to brick-red hue of the aged. Because of the extreme complexity of chemical compounds involved, many investigations have been made using model solutions of know composition rather than wine. Thus, there is a large amount of research still required to obtain an overall perspective of the anthocyanin composition and its change with time in red wines. Future findings may well greatly revise our current interpretation of the color in red wines. This paper summarizes the most recent advances in the studies of the anthocyanins derived pigments in red wines, as well as their color evolution.

  17. Evolution, nucleosynthesis and yields of low mass AGB stars at different metallicities (II): the FRUITY database

    CERN Document Server

    Cristallo, Sergio; Straniero, Oscar; Gallino, Roberto; Dominguez, Inma; Abia, Carlos; DiRico, Gianluca; Quintini, Massimo; Bisterzo, Sara

    2011-01-01

    By using updated stellar low mass stars models, we can systematically investigate the nucleosynthesis processes occurring in AGB stars, when these objects experience recurrent thermal pulses and third dredge-up episodes. In this paper we present the database dedicated to the nucleosynthesis of AGB stars: the FRUITY (FRANEC Repository of Updated Isotopic Tables & Yields) database. An interactive web-based interface allows users to freely download the full (from H to Bi) isotopic composition, as it changes after each third dredge-up episode and the stellar yields the models produce. A first set of AGB models, having masses in the range 1.5 < M/Msun < 3.0 and metallicities 1e-3 < Z < 2e-2, is discussed here. For each model, a detailed description of the physical and the chemical evolution is provided. In particular, we illustrate the details of the s-process and we evaluate the theoretical uncertainties due to the parametrization adopted to model convection and mass loss. The resulting nucleosynt...

  18. The ATLAS transverse momentum trigger evolution at the LHC towards Run II

    CERN Document Server

    Strubig, Antonia; The ATLAS collaboration

    2015-01-01

    The missing transverse momentum triggers of the ATLAS experiment at the CERN Large Hadron Collider (LHC) are designed to select collision events with non-interacting particles passing through the detector. Such events provide an interesting probe for new physics interactions beyond the Standard Model, but also provide the basis for precise measurements of Standard Model parameters such as the Higgs couplings. The transverse momentum used in the trigger system is calculated from calorimeter-based global energy sums and supplemented with information from the muon detection system. The trigger operated successfully during the first running period of the LHC. With the start-up in 2015, the LHC is now operating at a higher centre-of-mass energy and increased luminosity, both making it challenging to improve on the Run I performance. A brief summary of the Run I performance studies will be presented, together with the Run II software and hardware-based improvements as well as some of the first results from the Run ...

  19. The MassiveBlack-II Simulation: The Evolution of Halos and Galaxies to z~0

    CERN Document Server

    Khandai, Nishikanta; Croft, Rupert; Wilkins, Stephen M; Feng, Yu; Tucker, Evan; DeGraf, Colin; Liu, Mao-Sheng

    2014-01-01

    (Abridged for arXiv)We investigate the properties of halos, galaxies and blackholes to z=0 in the high resolution hydrodynamical simulation MassiveBlack-II (MBII) which evolves a LCDM cosmology in a comoving volume Vbox=100(Mpc/h)^3. MBII is the highest resolution simulation of this size which includes a self-consistent model for star formation, black hole accretion and associated feedback. We provide a simulation browser web application which enables interactive search and tagging of halos, subhalos and their properties and publicly release our galaxy catalogs. Our analysis of the halo mass function (MF) in MBII reveals that baryons have strong effects, with changes in the halo abundance of 20-35% below the knee of the MF (Mhalo =2. At z10^11 Msun) galaxies hosting bright AGNs make significant contributions to the GSMF. The quasar bolometric luminosity function is also largely consistent with observations. We note however that more efficient AGN feedback (beyond simple thermal coupling used here) is likely n...

  20. Mg II Absorber Number Density at z~0.05 Implications for Omega_DLA Evolution

    CERN Document Server

    Churchill, C W

    2001-01-01

    [Abridged] A 147 quasar/AGN spectra, obtained with FOS/HST, have been searched for Mg II absorbers for 0 = 0.06, yielding dN/dz = 0.22(+0.12)(-0.09) for absorbers with W_r > 0.6 Ang. This is consistent with the value expected if these systems do not evolve from higher redshifts (z = 2.2). (2) No systems with W_r 0.2 galaxies. (3) Three systems are candidates for damped Lyman-alpha absorbers (DLAs). Based upon the results of Rao & Turnshek (2000, ApJS, 130, 1), this translates to dN/dz = 0.08(+0.09)(-0.05) for DLAs at z ~ 0. This would suggest that dN/dz for DLAs does not evolve from z = 4 to z = 0. However, because of the distribution of H I mass in 21-cm selected galaxies, the Rao & Turnshek finding that the cosmological H I mass density, Omega_DLA, decreases either rapidly from z = 0.5 to z = 0, or more gradually from z = 1.5, still holds.

  1. Confronting uncertainties in stellar physics. II. Exploring differences in main-sequence stellar evolution tracks

    Science.gov (United States)

    Stancliffe, R. J.; Fossati, L.; Passy, J.-C.; Schneider, F. R. N.

    2016-02-01

    We assess the systematic uncertainties in stellar evolutionary calculations for low- to intermediate-mass, main-sequence stars. We compare published stellar tracks from several different evolution codes with our own tracks computed using the stellar codes stars and mesa. In particular, we focus on tracks of 1 and 3 M⊙ at solar metallicity. We find that the spread in the available 1 M⊙ tracks (computed before the recent solar composition revision) can be covered by tracks between 0.97-1.01 M⊙ computed with the stars code. We assess some possible causes of the origin of this uncertainty, including how the choice of input physics and the solar constraints used to perform the solar calibration affect the tracks. We find that for a 1 M⊙ track, uncertainties of around 10% in the initial hydrogen abundance and initial metallicity produce around a 2% error in mass. For the 3 M⊙ tracks, there is very little difference between the tracks from the various different stellar codes. The main difference comes in the extent of the main sequence, which we believe results from the different choices of the implementation of convective overshooting in the core. Uncertainties in the initial abundances lead to a 1-2% error in the mass determination. These uncertainties cover only part of the total error budget, which should also include uncertainties in the input physics (e.g., reaction rates, opacities, convective models) and any missing physics (e.g., radiative levitation, rotation, magnetic fields). Uncertainties in stellar surface properties such as luminosity and effective temperature will further reduce the accuracy of any potential mass determinations.

  2. Lagrangian theory of structure formation in relativistic cosmology. II. Average properties of a generic evolution model

    Science.gov (United States)

    Buchert, Thomas; Nayet, Charly; Wiegand, Alexander

    2013-06-01

    Kinematical and dynamical properties of a generic inhomogeneous cosmological model, spatially averaged with respect to free-falling (generalized fundamental) observers, are investigated for the matter model “irrotational dust.” Paraphrasing a previous Newtonian investigation, we present a relativistic generalization of a backreaction model based on volume-averaging the “relativistic Zel’dovich approximation.” In this model we investigate the effect of “kinematical backreaction” on the evolution of cosmological parameters as they are defined in an averaged inhomogeneous cosmology, and we show that the backreaction model interpolates between orthogonal symmetry properties by covering subcases of the plane-symmetric solution, the Lemaître-Tolman-Bondi solution and the Szekeres solution. We so obtain a powerful model that lays the foundations for quantitatively addressing curvature inhomogeneities as they would be interpreted as “dark energy” or “dark matter” in a quasi-Newtonian cosmology. The present model, having a limited architecture due to an assumed Friedmann-Lemaître-Robertson-Walker background, is nevertheless capable of replacing 1/4 of the needed amount for dark energy on domains of 200 Mpc in diameter for typical (one-sigma) fluctuations in a cold dark matter initial power spectrum. However, the model is far from explaining dark energy on larger scales (spatially), where a 6% effect on 400 Mpc domains is identified that can be traced back to an on average negative intrinsic curvature today. One drawback of the quantitative results presented is the fact that the epoch when backreaction is effective on large scales and leads to volume acceleration lies in the future. We discuss this issue in relation to the initial spectrum, the dark matter problem, the coincidence problem, and the fact that large-scale dark energy is an effect on the past light cone (not spatial), and we pinpoint key elements of future research.

  3. Evidence for transitional stages in the evolution of euglenid group II introns and twintrons in the Monomorphina aenigmatica plastid genome.

    Directory of Open Access Journals (Sweden)

    Jean-François Pombert

    Full Text Available BACKGROUND: Photosynthetic euglenids acquired their plastid by secondary endosymbiosis of a prasinophyte-like green alga. But unlike its prasinophyte counterparts, the plastid genome of the euglenid Euglena gracilis is riddled with introns that interrupt almost every protein-encoding gene. The atypical group II introns and twintrons (introns-within-introns found in the E. gracilis plastid have been hypothesized to have been acquired late in the evolution of euglenids, implying that massive numbers of introns may be lacking in other taxa. This late emergence was recently corroborated by the plastid genome sequences of the two basal euglenids, Eutreptiella gymnastica and Eutreptia viridis, which were found to contain fewer introns. METHODOLOGY/PRINCIPAL FINDINGS: To gain further insights into the proliferation of introns in euglenid plastids, we have characterized the complete plastid genome sequence of Monomorphina aenigmatica, a freshwater species occupying an intermediate phylogenetic position between early and late branching euglenids. The M. aenigmatica UTEX 1284 plastid genome (74,746 bp, 70.6% A+T, 87 genes contains 53 intron insertion sites, of which 41 were found to be shared with other euglenids including 12 of the 15 twintron insertion sites reported in E. gracilis. CONCLUSIONS: The pattern of insertion sites suggests an ongoing but uneven process of intron gain in the lineage, with perhaps a minimum of two bursts of rapid intron proliferation. We also identified several sites that represent intermediates in the process of twintron evolution, where the external intron is in place, but not the internal one, offering a glimpse into how these convoluted molecular contraptions originate.

  4. The 2008 North Atlantic Spring Bloom Experiment II: Autonomous Platforms and Mixed Layer Evolution

    Science.gov (United States)

    Lee, C. M.; D'Asaro, E. A.; Perry, M.; Fennel, K.; Gray, A.; Rehm, E.; Briggs, N.; Sackmann, B. S.; Gudmundsson, K.

    2008-12-01

    The 2008 North Atlantic Spring Bloom Experiment (NAB08) employed a system of drifting floats, mobile gliders and ship-based measurements to resolve patch-scale physical and biological variability over the 3- month course of an entire bloom. Although both autonomous and ship-based elements were essential to achieving NAB08 goals, the autonomous system provided a novel perspective by employing long-range gliders to repeatedly survey the volume surrounding a drifting Lagrangian float, thus characterizing patch- scale bloom evolution. Integration of physical and biogeochemical sensors (temperature, conductivity, dissolved oxygen, chlorophyll and CDOM fluorescence, light transmission, optical backscatter, spectral light, and nitrate) and development of in situ calibration techniques were required to support this new autonomous approach. Energetic, small-scale eddy activity at the experiment site (southeast of Iceland, near the Joint Global Ocean Flux Study and Marine Light Mixed Layer sites) produced a swift, heterogeneous velocity field that challenged the gliders" operational abilities and drove refinements to the piloting techniques used to maintain float-following surveys. Although intentionally deployed outside of energetic eddies, floats and gliders were rapidly entrained into these features. Floats circulated within eddies near the start and end of the experiment, drifting generally northwest, across the basin, in-between. An eddy sampled late in the deployment provided particularly interesting signatures, with elevated biological signals manifest consistently in one quadrant. As measurements were collected in a parcel-following Lagrangian frame, this suggests energetic small-scale exchange process (such as vertical or lateral mixing) paired with fast-acting biological processes capable of modifying the newly entrained water as it navigates its path around the eddy. Despite this energetic kilometer-scale heterogeneity, broadly distributed platforms appeared to

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

    Directory of Open Access Journals (Sweden)

    Felipe J Fuzita

    Full Text Available 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

  6. The Unusual Temporal and Spectral Evolution of SN2011ht. II. Peculiar Type IIn or Impostor?

    Science.gov (United States)

    Humphreys, Roberta M.; Davidson, Kris; Jones, Terry J.; Pogge, R. W.; Grammer, Skyler H.; Prieto, José L.; Pritchard, T. A.

    2012-11-01

    SN2011ht has been described both as a true supernova (SN) and as an impostor. In this paper, we conclude that it does not match some basic expectations for a core-collapse event. We discuss SN2011ht's spectral evolution from a hot dense wind to a cool dense wind, followed by the post-plateau appearance of a faster low density wind during a rapid decline in luminosity. We identify a slow dense wind expanding at only 500-600 km s-1, present throughout the eruption. A faster wind speed V ~ 900 km s-1 occurred in a second phase of the outburst. There is no direct or significant evidence for any flow speed above 1000 km s-1 the broad asymmetric wings of Balmer emission lines in the hot wind phase were due to Thomson scattering, not bulk motion. We estimate a mass-loss rate of order 0.05 M ⊙ yr-1 during the hot dense wind phase of the event. The same calculations present difficulties for a hypothetical unseen SN blast wave. There is no evidence that the kinetic energy greatly exceeded the luminous energy, roughly 3 × 1049 erg so the radiative plus kinetic energy was small compared to a typical SN. We suggest that SN2011ht may have been a giant eruption driven by super-Eddington radiation pressure, perhaps beginning a few months before the discovery. A strongly non-spherical SN might also account for the data at the cost of more free parameters. Based on observations with the Large Binocular Telescope (LBT), an international collaboration among institutions in the United States, Italy, and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia. Based also on observations obtained at the

  7. Non-noble metal graphene oxide-copper (II) ions hybrid electrodes for electrocatalytic hydrogen evolution reaction

    KAUST Repository

    Muralikrishna, S.

    2015-08-25

    Non-noble metal and inexpensive graphene oxide-copper (II) ions (GO-Cu2+) hybrid catalysts have been explored for the hydrogen evolution reaction (HER). We were able to tune the binding abilities of GO toward the Cu2+ ions and hence their catalytic properties by altering the pH. We have utilized the oxygen functional moieties such as carboxylate, epoxide, and hydroxyl groups on the edge and basal planes of the GO for binding the Cu2+ ions through dative bonds. The GO-Cu2+ hybrid materials were characterized by cyclic voltammetry in sodium acetate buffer solution. The morphology of the hybrid GO-Cu2+ was characterized by atomic force microscopy. The GO-Cu2+ hybrid electrodes show good electrocatalytic activity for HER with low overpotential in acidic solution. The Tafel slope for the GO-Cu2+ hybrid electrode implies that the primary discharge step is the rate determining step and HER proceed with Volmer step. © 2015 American Institute of Chemical Engineers Environ Prog.

  8. NUMERICAL STUDY FOR THE NONLINEAR EVOLUTION OF VORTEX SHEET AND ITS APPLICATIONS:PART II.EVOLUTION OF WING SHEDDING VORTEX

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A numerical simulation was performed to study the roll-up of vortex sheet behind a slender delta-wing and the evolution of vortex layer shed by a plunging airfoil using the Multhopp superconvergence scheme given in Part I. Mathematical models, which are regular in the sense of Lighthill′s lemma, were proposed to simulate the vortex sheet evolution for side-slip and roll motion of wings, and solved numerically by using the superconvergence vortex method. An approach to investigate the vortex evolution in the near wake of the oscillating airfoil was also given. Our calculations have confirmed that the approach can reasonably predict the nonlinear evolution of vortex sheet.

  9. Expression of the nuclear encoded OEE1 protein is required for oxygen evolution and stability of photosystem II particles in Chlamydomonas reinhardtii.

    OpenAIRE

    Mayfield, S P; Bennoun, P; Rochaix, J D

    1987-01-01

    In Chlamydomonas reinhardtii the oxygen evolving enhancer protein 1 (OEE1), which is part of the oxygen evolving complex of photosystem II (PS II), is coded for by a single nuclear gene (psb1). The nuclear mutant FuD44 specifically lacks the OEE1 polypeptide and is completely deficient in photosynthetic oxygen evolution. In this mutant a 5 kb DNA insertion into the 5' region of the psb1 gene results in the complete absence of OEE1 mRNA and protein. A revertant, FuD44-R 2, which is capable of ...

  10. Biochemical adaptation to ocean acidification.

    Science.gov (United States)

    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

  11. The population of planetary nebulae and H II regions in M 81. A study of radial metallicity gradients and chemical evolution

    Science.gov (United States)

    Stanghellini, L.; Magrini, L.; Villaver, E.; Galli, D.

    2010-10-01

    Context. M 81 is an ideal laboratory to investigate the galactic chemical and dynamical evolution through the study of its young and old stellar populations. Aims: We analyze the chemical abundances of planetary nebulae and H ii regions in the M 81 disk for insight on galactic evolution, and compare it with that of other galaxies, including the Milky Way. Methods: We acquired Hectospec/MMT spectra of 39 PNe and 20 H ii regions, with 33 spectra viable for temperature and abundance analysis. Our PN observations represent the first PN spectra in M 81 ever published, while several H ii region spectra have been published before, although without a direct electron temperature determination. We determine elemental abundances of helium, nitrogen, oxygen, neon, sulfur, and argon in PNe and H ii regions, and determine their averages and radial gradients. Results: The average O/H ratio of PNe compared to that of the H ii regions indicates a general oxygen enrichment in M 81 in the last ~10 Gyr. The PN metallicity gradient in the disk of M 81 is Δlog(O/H)/ΔRG = -0.055 ± 0.02 dex/kpc. Neon and sulfur in PNe have a radial distribution similar to that of oxygen, with similar gradient slopes. If we combine our H ii sample with the one in the literature we find a possible mild evolution of the gradient slope, with results consistent with gradient steepening with time. Additional spectroscopy is needed to confirm this trend. There are no type I PNe in our M 81 sample, consistently with the observation of only the brightest bins of the PNLF, the galaxy metallicity, and the evolution of post-AGB shells. Conclusions: Both the young and the old populations of M 81 disclose shallow but detectable negative radial metallicity gradient, which could be slightly steeper for the young population, thus not excluding a mild gradients steepening with the time since galaxy formation. During its evolution M 81 has been producing oxygen; its total oxygen enrichment exceeds that of other nearby

  12. Dynamic analysis of biochemical network using complex network method

    Directory of Open Access Journals (Sweden)

    Wang Shuqiang

    2015-01-01

    Full Text Available In this study, the stochastic biochemical reaction model is proposed based on the law of mass action and complex network theory. The dynamics of biochemical reaction system is presented as a set of non-linear differential equations and analyzed at the molecular-scale. Given the initial state and the evolution rules of the biochemical reaction system, the system can achieve homeostasis. Compared with random graph, the biochemical reaction network has larger information capacity and is more efficient in information transmission. This is consistent with theory of evolution.

  13. Influence of different ruthenium(II) bipyridyl complex on the photocatalytic H{sub 2} evolution over TiO{sub 2} nanoparticles with mesostructures

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Tianyou [College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 (China); Hubei Key Laboratory for Catalysis and Material Science, College of Chemistry and Material Science, South-Central University for Nationalities, Wuhan 430074 (China); Ke, Dingning; Cai, Ping; Dai, Ke; Ma, Liang; Zan, Ling [College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072 (China)

    2008-05-15

    H{sub 2} production over dye-sensitized Pt/TiO{sub 2} nanoparticles with mesostructures (m-TiO{sub 2}) under visible light ({lambda} > 420 nm) was investigated by using methanol as electron donors. Experimental results indicate that three types of ruthenium(II) bipyridyl complex dyes (one binuclear Ru, two mononuclear Ru), which can be attached to Pt/m-TiO{sub 2} with different linkage modes, show different photosensitization effects due to their different coordination circumstances and physicochemical properties. The dye tightly linked with m-TiO{sub 2} has better durability but the lowest H{sub 2} evolution efficiency, whereas the loosely attached dyes possess higher H{sub 2} evolution efficiency and preferable durability. It seems that the dynamic equilibrium between the linkage of the ground state dye with TiO{sub 2} and the divorce of the oxidization state dye from the surfaces plays a crucial role in the photochemical behavior during the photocatalyst sensitization process. It is helpful to improve the H{sub 2} evolution efficiency by enhancing the electron injection and hindering the backward transfer. The binuclear Ru(II) dye shows a better photosensitization in comparison with mononuclear Ru(II) dyes due to its large molecular area, conjugation system, and ''antenna effect'', which, in turn, improve the visible light harvesting and electron transfer between the dye molecules and TiO{sub 2}. (author)

  14. Predictive biochemical assays for late radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, P.; Finkelstein, J.N.; Siemann, D.W.; Shapiro, D.L.; Van Houtte, P.; Penney, D.P.

    1986-04-01

    Surfactant precursors or other products of Type II pneumocytes have the potential to be the first biochemical marker for late radiation effects. This is particularly clinically important in the combined modality era because of the frequent occurrence of pneumonitis and pulmonary fibrosis secondary to radiation or chemotherapy. Accordingly, correlative studies have been pursued with the Type II pneumocyte as a beginning point to understand the complex pathophysiology of radiation pneumonitis and fibrosis. From our ultrastructural and biochemical studies, it is evident that Type II pneumocytes are an early target of radiation and the release of surfactant into the alveolus shortly after exposure persists for days and weeks. Through the use of lavaging techniques, alveolar surfactant has been elevated after pulmonary irradiation. In three murine strains and in the rabbit, there is a strong correlation with surfactant release at 7 and/or 28 days in vivo with later lethality in months. In vitro studies using cultures of type II pneumocytes also demonstrate dose response and tolerance factors that are comparable to the in vivo small and large animal diagnostic models. New markers are being developed to serve as a predictive index for later lethal pneumonopathies. With the development of these techniques, the search for early biochemical markers in man has been undertaken. Through the use of biochemical, histological, and ultrastructural techniques, a causal relationship between radiation effects on type II pneumocytes, pulmonary cells, endothelial cells of blood vessels, and their roles in the production of pneumonitis and fibrosis will evolve.

  15. Predictive biochemical assays for late radiation effects

    International Nuclear Information System (INIS)

    Surfactant precursors or other products of Type II pneumocytes have the potential to be the first biochemical marker for late radiation effects. This is particularly clinically important in the combined modality era because of the frequent occurrence of pneumonitis and pulmonary fibrosis secondary to radiation or chemotherapy. Accordingly, correlative studies have been pursued with the Type II pneumocyte as a beginning point to understand the complex pathophysiology of radiation pneumonitis and fibrosis. From our ultrastructural and biochemical studies, it is evident that Type II pneumocytes are an early target of radiation and the release of surfactant into the alveolus shortly after exposure persists for days and weeks. Through the use of lavaging techniques, alveolar surfactant has been elevated after pulmonary irradiation. In three murine strains and in the rabbit, there is a strong correlation with surfactant release at 7 and/or 28 days in vivo with later lethality in months. In vitro studies using cultures of type II pneumocytes also demonstrate dose response and tolerance factors that are comparable to the in vivo small and large animal diagnostic models. New markers are being developed to serve as a predictive index for later lethal pneumonopathies. With the development of these techniques, the search for early biochemical markers in man has been undertaken. Through the use of biochemical, histological, and ultrastructural techniques, a causal relationship between radiation effects on type II pneumocytes, pulmonary cells, endothelial cells of blood vessels, and their roles in the production of pneumonitis and fibrosis will evolve

  16. Impact of initial models and variable accretion rates on the pre-main-sequence evolution of massive and intermediate-mass stars and the early evolution of H II regions

    Science.gov (United States)

    Haemmerlé, Lionel; Peters, Thomas

    2016-05-01

    Massive star formation requires the accretion of gas at high rate while the star is already bright. Its actual luminosity depends sensitively on the stellar structure. We compute pre-main-sequence tracks for massive and intermediate-mass stars with variable accretion rates and study the evolution of stellar radius, effective temperature and ionizing luminosity, starting at 2 M⊙ with convective or radiative structures. The radiative case shows a much stronger swelling of the protostar for high accretion rates than the convective case. For radiative structures, the star is very sensitive to the accretion rate and reacts quickly to accretion bursts, leading to considerable changes in photospheric properties on time-scales as short as 100-1000 yr. The evolution for convective structures is much less influenced by the instantaneous accretion rate, and produces a monotonically increasing ionizing flux that can be many orders of magnitude smaller than in the radiative case. For massive stars, it results in a delay of the H II region expansion by up to 10 000 yr. In the radiative case, the H II region can potentially be engulfed by the star during the swelling, which never happens in the convective case. We conclude that the early stellar structure has a large impact on the radiative feedback during the pre-main-sequence evolution of massive protostars and introduces an important uncertainty that should be taken into account. Because of their lower effective temperatures, our convective models may hint at a solution to an observed discrepancy between the luminosity distribution functions of massive young stellar objects and compact H II regions.

  17. Evolution Inclusions and Variation Inequalities for Earth Data Processing II Differential-operator Inclusions and Evolution Variation Inequalities for Earth Data Processing

    CERN Document Server

    Zgurovsky, Mikhail Z; Kasyanov, Pavlo O

    2011-01-01

    Here, the authors present modern mathematical methods to solve problems of differential-operator inclusions and evolution variation inequalities which may occur in fields such as geophysics, aerohydrodynamics, or fluid dynamics. For the first time, they describe the detailed generalization of various approaches to the analysis of fundamentally nonlinear models and provide a toolbox of mathematical equations. These new mathematical methods can be applied to a broad spectrum of problems. Examples of these are phase changes, diffusion of electromagnetic, acoustic, vibro-, hydro- and seismoacousti

  18. Simulation of Biochemical Pathway Adaptability Using Evolutionary Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    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

  19. Phenotype prediction of nonsynonymous single nucleotide polymorphisms in human phase II drug/xenobiotic metabolizing enzymes: perspectives on molecular evolution

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Nonsynonymous single nucleotide polymorphisms (nsSNPs) in coding regions can lead to amino acid changes that might alter the protein’s function and account for susceptibility to disease and altered drug/xenobiotic response. Many nsSNPs have been found in genes encoding human phase II metabolizing enzymes; however, there is little known about the relationship between the genotype and phenotype of nsSNPs in these enzymes. We have identified 923 validated nsSNPs in 104 human phase II enzyme genes from the Ensembl genome database and the NCBI SNP database. Using PolyPhen, Panther, and SNAP algorithms, 44%?59% of nsSNPs in phase II enzyme genes were predicted to have functional impacts on protein function. Predictions largely agree with the available experimental annotations. 68% of deleterious nsSNPs were correctly predicted as damaging. This study also identified many amino acids that are likely to be functionally critical, but have not yet been studied experimentally. There was significant concordance between the predicted results of Panther and PolyPhen, and between SNAP non-neutral predictions and PolyPhen scores. Evolutionarily non-neutral (destabilizing) amino acid substitutions are thought to be the pathogenetic basis for the alteration of phase II enzyme activity and to be associated with disease susceptibility and drug/xenobiotic toxicity. Furthermore, the molecular evolutionary patterns of phase II enzymes were characterized with regards to the predicted deleterious nsSNPs.

  20. Ultracold fermions in real or fictitious magnetic fields: BCS-BEC evolution and type-I-type-II transition

    International Nuclear Information System (INIS)

    We study ultracold neutral fermion superfluids in the presence of fictitious magnetic fields, as well as charged fermion superfluids in the presence of real magnetic fields. Charged fermion superfluids undergo a phase transition from type-I to type-II superfluidity, where the magnetic properties of the superfluid change from being a perfect diamagnet without vortices to a partial diamagnet with the emergence of the Abrikosov vortex lattice. The transition from type-I to type-II superfluidity is tuned by changing the scattering parameter (interaction) for fixed density. We also find that neutral fermion superfluids such as 6Li and 40K are extreme type-II superfluids and are more robust to the penetration of a fictitious magnetic field in the BCS-BEC crossover region near unitarity, where the critical fictitious magnetic field reaches a maximum as a function of the scattering parameter (interaction).

  1. Recent abstracts in biochemical technology

    OpenAIRE

    R R Siva Kiran; Brijesh P

    2008-01-01

    “Recent abstracts in biochemical technology” is a collection of interesting research articles published in “List of biochemical technology journals” (Table 1). The abstracts are most likely to report significant results in biochemical technology.

  2. Evolution of the Milky Way with radial motions of stars and gas II. The evolution of abundance profiles from H to Ni

    CERN Document Server

    Kubryk, M; Athanassoula, E

    2014-01-01

    We study the role of radial motions of stars and gas on the evolution of abundance profiles in the Milky Way disk. We investigate, in a parametrized way, the impact of radial flows of gas and radial migration of stars induced mainly by the Galactic bar and its iteraction with the spiral arms. We use a model with several new or up-dated ingredients (atomic and molecular gas phases, star formation depending on molecular gas, recent sets of metallicity-dependent stellar yields from H to Ni, observationally inferred SNIa rates), which reproduces well most global and local observables of the Milky Way. We obtain abundance profiles flattening both in the inner disk (because of radial flows) and in the outer disk (because of the adopted star formation law). The gas abundance profiles flatten with time, but the corresponding stellar profiles appear to be steeper for younger stars, because of radial migration. We find a correlation between the stellar abundance profiles and O/Fe, which is a proxy for stellar age. Our ...

  3. Purifying Selection and Birth-and-Death Evolution in the Class II Hydrophobin Gene Families of the Ascomycete Trichoderma/Hypocrea

    Energy Technology Data Exchange (ETDEWEB)

    kubicek, Christian P.; Baker, Scott E.; Gamauf, Christian; Kenerley, Chuck; Druzhinina, Irina S.

    2008-01-10

    Hydrophobins are proteins containing eight conserved cysteine residues that occur uniquely in mycelial fungi, where their main function is to confer hydrophobicity to fungal surfaces in contact with air and during attachment of hyphae to hydrophobic surfaces of hosts, symbiotic partners or of themselves resulting in morphogenetic signals. Based on their hydropathy patterns and their solubility characteristics, they are classified in class I and class II hydrophobins, the latter being found only in ascomycetes. Here we have investigated the mechanisms driving the evolution of the class II hydrophobins in nine species of the mycoparasitic ascomycetous genus Trichoderma/Hypocrea, using three fully sequenced genomes (H. jecorina=T. reesei, H. atroviridis=T. atroviride; H. virens=T. virens) and a total of 14.000 ESTs of six others (T. asperellum, H. lixii=T. harzianum, T. aggressivum var. europeae, T. longibrachiatum, T. cf. viride). The former three contained six, ten and nine members, which is the highest number found in any other ascomycete so far. They all showed the conserved four beta-strands/one helix structure, which is stabilized by four disulfide bonds. In addition, a small number of these HFBs contained an extended N-terminus rich in either praline and aspartate, or glycine-asparagine. Phylogenetic analysis reveals a mosaic of terminal clades contain duplicated genes and shows only three reasonably supported clades. Calculation of the ratio of differences in synonymous vs. non-synonymous nucleotide substitutions provides evidence for strong purifying selection (KS/Ka >> 1). A genome database search for class II HFBs from other ascomycetes retrieved a much smaller number of hydrophobins (2-4) from each species, and most of them were from Pyrenomycetes. A combined phylogeny of these sequences with those of Trichoderma showed that the Trichoderma HFBs mostly formed their own clades, whereas those of other pyrenomycetes occured in shared clades. Our study shows

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

    Science.gov (United States)

    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.

  5. Complete multiwavelength evolution of galactic black hole transients during outburst decay. II. Compact jets and X-ray variability properties

    Energy Technology Data Exchange (ETDEWEB)

    Dinçer, T.; Kalemci, E. [Faculty of Engineering and Natural Sciences, Sabancı University, Orhanlı-Tuzla 34956, İstanbul (Turkey); Tomsick, J. A. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450 (United States); Buxton, M. M.; Bailyn, C. D. [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

    2014-11-01

    We investigated the relation between compact jet emission and X-ray variability properties of all black hole transients with multiwavelength coverage during their outburst decays. We studied the evolution of all power spectral components (including low-frequency quasi-periodic oscillations; QPOs), and related this evolution to changes in jet properties tracked by radio and infrared observations. We grouped sources according to their tracks in the radio/X-ray luminosity relation and show that the standards show stronger broadband X-ray variability than outliers at a given X-ray luminosity when the compact jet turns on. This trend is consistent with the internal shock model and can be important for the understanding of the presence of tracks in the radio/X-ray luminosity relation. We also observed that the total and the QPO rms amplitudes increase together during the earlier part of the outburst decay, but after the compact jet turns, either the QPO disappears or its rms amplitude decreases significantly while the total rms amplitudes remain high. We discuss these results with a scenario including a variable corona and a non-variable disk with a mechanism for the QPO separate from the mechanism that creates broad components. Finally, we evaluated the timing predictions of the magnetically dominated accretion flow model that can explain the presence of tracks in the radio/X-ray luminosity relation.

  6. Evolution of EF-hand calcium-modulated proteins. II. Domains of several subfamilies have diverse evolutionary histories

    Science.gov (United States)

    Nakayama, S.; Moncrief, N. D.; Kretsinger, R. H.

    1992-01-01

    In the first report in this series we described the relationships and evolution of 152 individual proteins of the EF-hand subfamilies. Here we add 66 additional proteins and define eight (CDC, TPNV, CLNB, LPS, DGK, 1F8, VIS, TCBP) new subfamilies and seven (CAL, SQUD, CDPK, EFH5, TPP, LAV, CRGP) new unique proteins, which we assume represent new subfamilies. The main focus of this study is the classification of individual EF-hand domains. Five subfamilies--calmodulin, troponin C, essential light chain, regulatory light chain, CDC31/caltractin--and three uniques--call, squidulin, and calcium-dependent protein kinase--are congruent in that all evolved from a common four-domain precursor. In contrast calpain and sarcoplasmic calcium-binding protein (SARC) each evolved from its own one-domain precursor. The remaining 19 subfamilies and uniques appear to have evolved by translocation and splicing of genes encoding the EF-hand domains that were precursors to the congruent eight and to calpain and to SARC. The rates of evolution of the EF-hand domains are slower following formation of the subfamilies and establishment of their functions. Subfamilies are not readily classified by patterns of calcium coordination, interdomain linker stability, and glycine and proline distribution. There are many homoplasies indicating that similar variants of the EF-hand evolved by independent pathways.

  7. Speed evolution of fast CME/shocks with SOHO/LASCO, WIND/WAVES, IPS and in-situ WIND data: analysis of kilometric type-II emissions

    Directory of Open Access Journals (Sweden)

    A. Gonzalez-Esparza

    2009-10-01

    Full Text Available Fast CME/shocks propagating in the interplanetary medium can generate kilometric Type II (km-TII radio emissions at the local plasma frequency and/or its harmonic, so these radio emissions provide a means of remotely tracking CME/shocks. We apply a new analysis technique, using the frequency drift of km-TII spectrum obtained by the Thermal Noise Receiver (TNR of the WIND/WAVES experiment, to infer, at some adequate intervals, the propagation speed of six CME/shocks. We combine these results with previously reported speeds from coronagraph white light and interplanetary scintillation observations, and in-situ measurements, to study the temporal speed evolution of the six events. The speed values obtained by the km-TII analysis are in a reasonable agreement with the speed measurements obtained by other techniques at different heliocentric distance ranges. The combination of all the speed measurements show a gradual deceleration of the CME/shocks as they propagate to 1 AU. This new technique can be useful in studying the evolution of fast CME/shocks when adequate intervals of km-TII emissions are available.

  8. Starspot evolution, differential rotation, and magnetic cycles in the chromospherically active binaries lambda andromedae, sigma Geminorum, II Pegasi, and V711 Tauri

    Science.gov (United States)

    Henry, Gregory W.; Eaton, Joel A.; Hamer, Jamesia; Hall, Douglas S.

    1995-01-01

    We have analyzed 15-19 yr of photoelectric photometry, obtained manually and with automated telescopes, of the chromospherically active binaries lambda And, sigma Gem, II Peg, and V711 Tau. These observations let us identify individual dark starspots on the stellar surfaces from periodic dimming of the starlight, follow the evolution of these spots, and search for long-term cyclic changes in the properties of these starspots that might reveal magnetic cycles analogous to the Sun's 11 yr sunspot cycle. We developed a computer code to fit a simple two-spot model to our observed light curves that allows us to extract the most easily determinable and most reliable spot parameters from the light curves, i.e., spot longitudes and radii. We then used these measured properties to identify individual spots and to chart their life histories by constructing migration and amplitude curves. We identified and followed 11 spots in lambda And, 16 in sigma Gem, 12 in II Peg, and 15 in V711 Tau. Lifetimes of individual spots ranged from a few months to longer than 6 yr. Differential rotation coefficients, estimated from the observed range of spot rotation periods for each star and defined by equation (2), were 0.04 for lambda And, 0.038 for sigma Gem, 0.005 for II Peg, and 0.006 for V711 Tau, versus 0.19 for the Sun. We searched for cyclic changes in mean brightness, B-V color index, and spot rotation period as evidence for long-term cycles. Of these, long-term variability in mean brightness appears to offer the best evidence for such cycles in these four stars. Cycles of 11.1 yr for lambda And, 8.5 yr for sigma Gem, 11 yr for II Peg, and 16 yr V711 Tau are implied by these mean brightness changes. Cyclic changes in spot rotation period were found in lambda And and possibly II Peg. Errors in B-V were too large for any long-term changes to be detectable.

  9. Evolution of the P-type II ATPase gene family in the fungi and presence of structural genomic changes among isolates of Glomus intraradices

    Directory of Open Access Journals (Sweden)

    Sanders Ian R

    2006-03-01

    Full Text Available Abstract Background The P-type II ATPase gene family encodes proteins with an important role in adaptation of the cell to variation in external K+, Ca2+ and Na2+ concentrations. The presence of P-type II gene subfamilies that are specific for certain kingdoms has been reported but was sometimes contradicted by discovery of previously unknown homologous sequences in newly sequenced genomes. Members of this gene family have been sampled in all of the fungal phyla except the arbuscular mycorrhizal fungi (AMF; phylum Glomeromycota, which are known to play a key-role in terrestrial ecosystems and to be genetically highly variable within populations. Here we used highly degenerate primers on AMF genomic DNA to increase the sampling of fungal P-Type II ATPases and to test previous predictions about their evolution. In parallel, homologous sequences of the P-type II ATPases have been used to determine the nature and amount of polymorphism that is present at these loci among isolates of Glomus intraradices harvested from the same field. Results In this study, four P-type II ATPase sub-families have been isolated from three AMF species. We show that, contrary to previous predictions, P-type IIC ATPases are present in all basal fungal taxa. Additionally, P-Type IIE ATPases should no longer be considered as exclusive to the Ascomycota and the Basidiomycota, since we also demonstrate their presence in the Zygomycota. Finally, a comparison of homologous sequences encoding P-type IID ATPases showed unexpectedly that indel mutations among coding regions, as well as specific gene duplications occur among AMF individuals within the same field. Conclusion On the basis of these results we suggest that the diversification of P-Type IIC and E ATPases followed the diversification of the extant fungal phyla with independent events of gene gains and losses. Consistent with recent findings on the human genome, but at a much smaller geographic scale, we provided evidence

  10. Optical and infrared properties of V1647 Orionis during the 2003-2006 outburst. II. Temporal evolution of the eruptive source

    CERN Document Server

    Fedele, D; Petr-Gotzens, M G; Rafanelli, P

    2007-01-01

    The occurrence of new FU Orionis-like objects is fundamental to understand the outburst mechanism in young stars and their role in star formation and disk evolution. Our work is aimed at investigating the properties of the recent outburst of V1647 Ori. Using optical and mid infrared long slit spectroscopy we monitored V1647 Ori in outburst between February 2004 and January 2006. The optical spectrum is characterized by Halpha and Hbeta in P-Cygni profile and by many weak FeI and FeII emission lines. Short timescale variability was measured in the continuum and line emission. On January 2006 we detected for the first time forbidden emission lines ([OI], [SII] and [FeII]). These lines are likely produced by an Herbig-Haro object driven by V1647 Ori. The mid infrared the spectrum of V1647 Ori is flat and featureless at all epochs. The SED changed drastically: the source was much redder in the early outburst than in the final phase. The magnitude rise and the SED of V1647 Ori resembles that of a FUor while the du...

  11. SN 2005cs in M51 II. Complete Evolution in the Optical and the Near-Infrared

    CERN Document Server

    Pastorello, A; Zampieri, L; Navasardyan, H; Taubenberger, S; Smartt, S J; Arkharov, A A; Baernbantner, O; Barwig, H; Benetti, S; Birtwhistle, P; Botticella, M T; Cappellaro, E; Del Principe, M; Di Mille, F; Di Rico, G; Dolci, M; Elias-Rosa, N; Efimova, N V; Fiedler, M; Harutyunyan, A; Hoeflich, P A; Kloehr, W; Larionov, V M; Lorenzi, V; Maund, J R; Napoleone, N; Ragni, M; Richmond, M; Ries, C; Spiro, S; Temporin, S; Turatto, M; Wheeler, J C

    2009-01-01

    We present the results of the one year long observational campaign of the type II-plateau SN 2005cs, which exploded in the nearby spiral galaxy M51 (the Whirlpool Galaxy). This extensive dataset makes SN 2005cs the best observed low-luminosity, 56Ni-poor type II-plateau event so far and one of the best core-collapse supernovae ever. The optical and near-infrared spectra show narrow P-Cygni lines characteristic of this SN family, which are indicative of a very low expansion velocity (about 1000 km/s) of the ejected material. The optical light curves cover both the plateau phase and the late-time radioactive tail, until about 380 days after core-collapse. Numerous unfiltered observations obtained by amateur astronomers give us the rare opportunity to monitor the fast rise to maximum light, lasting about 2 days. In addition to optical observations, we also present near-infrared light curves that (together with already published UV observations) allow us to construct for the first time a reliable bolometric light...

  12. Evolution of phase space densities from the dayside to nightside magnetosphere during a prolonged northward-IMF period: Cluster-II, GEOTAIL, and LANL-MPA comparison

    Science.gov (United States)

    Seki, K.; Lavraud, B.; Thomsen, M. F.; Elphic, R. C.; Matsumoto, Y.; Mukai, T.; Saito, Y.; Rème, H.; Fazakerley, A. N.

    2004-12-01

    It is observationally known that the plasma sheet becomes much cooler and denser than usual under prolonged northward interplanetary magnetic field (IMF) conditions [e.g., Terasawa et al., 1997]. However, the mechanism responsible for the formation of CDPS is still far from understood. The Kelvin-Helmholtz (K-H) instability driven by the velocity shear at the magnetopause has been proposed as a possible mechanism of magnetosheath plasma entry through the LLBL [Fujimoto and Terasawa, 1994; Otto and Fairfield, 2000; Hasegawa et al., 2004]. Double lobe reconnection, i.e., reconnection of a magnetosheath flux tube with lobe field at the high-latitude magnetopause in both hemispheres, thereby becoming closed, is also an important candidate process for the dense, thick LLBL formation during northward IMF periods [e.g., Song and Russell, 1992]. On the basis of evolution of electron and ion phase space densities (PSDs) from the dayside to the nightside magnetosphere observed by Cluster II, GEOTAIL, and LANL-MPA spacecraft during a northward IMF interval on March 16, 2002, we examine the relative importance of the K-H instability and double lobe reconnection for formation of the CDPS. This event corresponds to one of the CDPS events at geosynchronous orbit during prolonged northward IMF periods [Thomsen et al., 2003]. The heated electron signature observed by Cluster II indicates that formation of closed flux tube(s) through lobe reconnection in both northern and southern hemispheres indeed took place during the event. Comparison of PSDs between the newly closed flux tube observed by Cluster II and the dusk-flank LLBL by GEOTAIL indicates that double lobe reconnection is responsible for formation of the outer-LLBL. On the other hand, GEOTAIL observed wavy structures in the dusk LLBL, and comparison with results from numerical simulation of the K-H instability [Matsumoto et al., 2004] suggests that the observed structure is consistent with the non-linear phase of K

  13. Weak convergence of finite element approximations of linear stochastic evolution equations with additive noise II. Fully discrete schemes

    CERN Document Server

    Kovács, M; Lindgren, F

    2012-01-01

    We present an abstract framework for analyzing the weak error of fully discrete approximation schemes for linear evolution equations driven by additive Gaussian noise. First, an abstract representation formula is derived for sufficiently smooth test functions. The formula is then applied to the wave equation, where the spatial approximation is done via the standard continuous finite element method and the time discretization via an I-stable rational approximation to the exponential function. It is found that the rate of weak convergence is twice that of strong convergence. Furthermore, in contrast to the parabolic case, higher order schemes in time, such as the Crank-Nicolson scheme, are worthwhile to use if the solution is not very regular. Finally we apply the theory to parabolic equations and detail a weak error estimate for the linearized Cahn-Hilliard-Cook equation as well as comment on the stochastic heat equation.

  14. Multilevel selection in models of prebiotic evolution II: a direct comparison of compartmentalization and spatial self-organization.

    Directory of Open Access Journals (Sweden)

    Nobuto Takeuchi

    2009-10-01

    Full Text Available Multilevel selection has been indicated as an essential factor for the evolution of complexity in interacting RNA-like replicator systems. There are two types of multilevel selection mechanisms: implicit and explicit. For implicit multilevel selection, spatial self-organization of replicator populations has been suggested, which leads to higher level selection among emergent mesoscopic spatial patterns (traveling waves. For explicit multilevel selection, compartmentalization of replicators by vesicles has been suggested, which leads to higher level evolutionary dynamics among explicitly imposed mesoscopic entities (protocells. Historically, these mechanisms have been given separate consideration for the interests on its own. Here, we make a direct comparison between spatial self-organization and compartmentalization in simulated RNA-like replicator systems. Firstly, we show that both mechanisms achieve the macroscopic stability of a replicator system through the evolutionary dynamics on mesoscopic entities that counteract that of microscopic entities. Secondly, we show that a striking difference exists between the two mechanisms regarding their possible influence on the long-term evolutionary dynamics, which happens under an emergent trade-off situation arising from the multilevel selection. The difference is explained in terms of the difference in the stability between self-organized mesoscopic entities and externally imposed mesoscopic entities. Thirdly, we show that a sharp transition happens in the long-term evolutionary dynamics of the compartmentalized system as a function of replicator mutation rate. Fourthly, the results imply that spatial self-organization can allow the evolution of stable folding in parasitic replicators without any specific functionality in the folding itself. Finally, the results are discussed in relation to the experimental synthesis of chemical Darwinian systems and to the multilevel selection theory of

  15. Modelling ¹⁸O₂ and ¹⁶O₂ unidirectional fluxes in plants: II. analysis of rubisco evolution.

    Science.gov (United States)

    André, Marcel J

    2011-02-01

    The studies of Rubisco characteristics observed during plant evolution show that the variation of the Rubisco specificity factor only improved by two times from cyanobacteria to modern C3 plants. However we note important variations of the ratio between the maximum rates of oxygenation and carboxylation (V(O)/V(C)). Modelling in vivo ¹⁸O₂ data in plant gas exchange shows that the oxygenation reaction of Rubisco plays a regulating role when the photochemical energy exceeds the carboxylation capacity. A protective index 'oxygenation capacity' is postulated, related to the ratio V(O)/V(C) of Rubisco, and hence to the sink energy effect of photorespiration. Analysing the trends of Rubisco parameters along the evolutionary scale, we show: (1) the increase of both V(C) and V(O); (2) the enhancement of CO₂ affinity; and (3) the rise in oxygenation capacity at the expense of the CO₂ specificity. Hence, the factors of evolutionary pressure have not only directed the enzyme towards a more efficient utilisation of CO₂, but mainly to positively use the unavoidable great loss of energy and assimilated carbon in the process of photorespiration. These observations reinforce the hypothesis of plant-atmosphere co-evolution and of the complex role of Rubisco, which seems to be selected to develop both better CO₂ affinity and oxygenation capacity. The latter increases the capacity of sink of photorespiration, in particular, during water stress or under high irradiance, the two conditions experienced by plants in terrestrial environments. These observations help to explain some handicaps of C4 plants, and the supremacy of CAM and C3 perennial higher plants in arid environments.

  16. Measures of Biochemical Sociology

    Science.gov (United States)

    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…

  17. Biochemical Education in Brazil.

    Science.gov (United States)

    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)

  18. Evolution of linear absorption and nonlinear optical properties in V-shaped ruthenium(II)-based chromophores.

    Science.gov (United States)

    Coe, Benjamin J; Foxon, Simon P; Harper, Elizabeth C; Helliwell, Madeleine; Raftery, James; Swanson, Catherine A; Brunschwig, Bruce S; Clays, Koen; Franz, Edith; Garín, Javier; Orduna, Jesús; Horton, Peter N; Hursthouse, Michael B

    2010-02-10

    In this article, we describe a series of complexes with electron-rich cis-{Ru(II)(NH(3))(4)}(2+) centers coordinated to two pyridyl ligands bearing N-methyl/arylpyridinium electron-acceptor groups. These V-shaped dipolar species are new, extended members of a class of chromophores first reported by us (Coe, B. J. et al. J. Am. Chem. Soc. 2005, 127, 4845-4859). They have been isolated as their PF(6)(-) salts and characterized by using various techniques including (1)H NMR and electronic absorption spectroscopies and cyclic voltammetry. Reversible Ru(III/II) waves show that the new complexes are potentially redox-switchable chromophores. Single crystal X-ray structures have been obtained for four complex salts; three of these crystallize noncentrosymmetrically, but with the individual molecular dipoles aligned largely antiparallel. Very large molecular first hyperpolarizabilities beta have been determined by using hyper-Rayleigh scattering (HRS) with an 800 nm laser and also via Stark (electroabsorption) spectroscopic studies on the intense, visible d --> pi* metal-to-ligand charge-transfer (MLCT) and pi --> pi* intraligand charge-transfer (ILCT) bands. The latter measurements afford total nonresonant beta(0) responses as high as ca. 600 x 10(-30) esu. These pseudo-C(2v) chromophores show two substantial components of the beta tensor, beta(zzz) and beta(zyy), although the relative significance of these varies with the physical method applied. According to HRS, beta(zzz) dominates in all cases, whereas the Stark analyses indicate that beta(zyy) is dominant in the shorter chromophores, but beta(zzz) and beta(zyy) are similar for the extended species. In contrast, finite field calculations predict that beta(zyy) is always the major component. Time-dependent density functional theory calculations predict increasing ILCT character for the nominally MLCT transitions and accompanying blue-shifts of the visible absorptions, as the ligand pi-systems are extended. Such unusual

  19. On the orbital evolution of a giant planet pair embedded in a gaseous disk. II. A Saturn-Jupiter configuration

    CERN Document Server

    Zhang, Hui

    2010-01-01

    We carry out a series of high-resolution (1024 X 1024) hydrodynamic simulations to investigate the orbital evolution of a Saturn-Jupiter pair embedded in a gaseous disk. This work extends the results of our previous work by exploring a different orbital configuration---Jupiter lies outside Saturn (qd_{iLr}, where d_{iLr} is the distance between Jupiter and its first inner Lindblad resonance), the two planets undergo divergent migration. However, the inward migration of Saturn could be halted when Jupiter compresses the inner disk in which Saturn is embedded. (2) Convergent migration occurs when the initial separation is smaller (d

  20. The growth of disks and bulges during hierarchical galaxy formation. II: metallicity, stellar populations and dynamical evolution

    CERN Document Server

    Tonini, Chiara; Wyithe, J Stuart B; Croton, Darren J

    2016-01-01

    We investigate the properties of the stellar populations of model galaxies, using the new semi-analytic model presented in Tonini et al. (2016a). This new model follows the angular momentum evolution of gas and stars, providing the base for a new star formation recipe, and treatment of the effects of mergers that depends on the central galaxy dynamical structure. We find that the new recipes have the effect of boosting the efficiency of the baryonic cycle in producing and recycling metals, as well as preventing minor mergers from diluting the metallicity of bulges and ellipticals. The model reproduces the stellar mass - stellar metallicity relation for galaxies above 1e10 solar masses, including Brightest Cluster Galaxies. Model disks, galaxies dominated by instability-driven components, and merger-driven objects each stem from different evolutionary channels. These model galaxies therefore occupy different loci in the galaxy mass - size relation, which we find to be in accord with the Atlas 3D classification...

  1. ON THE ORBITAL EVOLUTION OF A GIANT PLANET PAIR EMBEDDED IN A GASEOUS DISK. II. A SATURN-JUPITER CONFIGURATION

    International Nuclear Information System (INIS)

    We carry out a series of high-resolution (1024 x 1024) hydrodynamic simulations to investigate the orbital evolution of a Saturn-Jupiter pair embedded in a gaseous disk. This work extends the results of our previous work by exploring a different orbital configuration-Jupiter lies outside Saturn (q i /Mo is the mass ratio of the inner planet and the outer one). We focus on the effects of different initial separations (d) between the two planets and the various surface density profiles of the disk, where σ ∝ r -α. We also compare the results of different orbital configurations of the planet pair. Our results show that (1) when the initial separation is relatively large (d>d iLr, where d iLr is the distance between Jupiter and its first inner Lindblad resonance), the two planets undergo divergent migration. However, the inward migration of Saturn could be halted when Jupiter compresses the inner disk in which Saturn is embedded. (2) Convergent migration occurs when the initial separation is smaller (d iLr) and the density slope of the disk is nearly flat (α S ∼ 0.4-0.5) by the MMRs and the system could maintain stability. These results explain the formation of MMRs in the exoplanet systems where the outer planet is more massive than the inner one. It also helps us to understand the origin of the 'hot Jupiter/Saturn' with a highly eccentric orbit.

  2. Variations on a theme - the evolution of hydrocarbon solids: II. Optical property modelling - the optEC(s) model

    CERN Document Server

    Jones, A P

    2015-01-01

    Context. The properties of hydrogenated amorphous carbon (a-C:H) dust are known to evolve in response to the local conditions. Aims. We present an adaptable model for the determination of the optical properties of low-temperature, interstellar a-C:H grains that is based on the fundamental physics of their composition. Methods. The imaginary part of the refractive index, k, for a-C:H materials, from 50 eV to cm wavelengths, is derived and the real part, n, of the refractive index is then calculated using the Kramers-Kronig relations. Results. The formulated optEC(s) model allows a determination of the complex dielectric function, epsilon, and refractive index, m(n, k), for a-C:H materials as a continuous function the band gap, Eg , which is shown to lie in the range = -0.1 to 2.7 eV. We provide expressions that enable a determination of their optical constants and tabulate m(n, k, Eg ) for 14 different values of Eg . We explore the evolution of the likely extinction and emission behaviours of a-C:H grains and ...

  3. Distance determination for RAVE stars using stellar models II: Most likely values assuming a standard stellar evolution scenario

    CERN Document Server

    Zwitter, T; Breddels, M A; Smith, M C; Helmi, A; Munari, U; Bienaym\\'{e), O; Bland-Hawthorn, J; Boeche, C; Brown, A G A; Campbell, R; Freeman, K C; Fulbright, J; Gibson, B; Gilmore, G; Grebel, E K; Navarro, J F; Parker, Q A; Seabroke, G M; Siebert, A; Siviero, A; Steinmetz, M; Watson, F G; Williams, M; Wyse, R F G

    2010-01-01

    The RAdial Velocity Experiment (RAVE) is a spectroscopic survey of the Milky Way. We use the subsample of spectra with spectroscopically determined values of stellar parameters to determine the distances to these stars. The list currently contains 235,064 high quality spectra which show no peculiarities and belong to 210,872 different stars. The numbers will grow as the RAVE survey progresses. The public version of the catalog will be made available through the CDS services along with the ongoing RAVE public data releases. The distances are determined with a method based on the work by Breddels et al.~(2010). Here we assume that the star undergoes a standard stellar evolution and that its spectrum shows no peculiarities. The refinements include: the use of either of the three isochrone sets, a better account of the stellar ages and masses, use of more realistic errors of stellar parameter values, and application to a larger dataset. The derived distances of both dwarfs and giants match within ~21% to the astr...

  4. Quantum chemistry of the oxygen evolution reaction on cobalt(ii,iii) oxide - implications for designing the optimal catalyst.

    Science.gov (United States)

    Plaisance, Craig P; Reuter, Karsten; van Santen, Rutger A

    2016-07-01

    Density functional theory is used to examine the changes in electronic structure that occur during the oxygen evolution reaction (OER) catalyzed by active sites on three different surface terminations of Co3O4. These three active sites have reactive oxo species with differing degrees of coordination by Co cations - a μ(3)-oxo on the (311) surface, a μ(2)-oxo on the (110)-A surface, and an η-oxo on the (110)-B surface. The kinetically relevant step on all surfaces over a wide range of applied potentials is the nucleophilic addition of water to the oxo, which is responsible for formation of the O-O bond. The intrinsic reactivity of a site for this step is found to increase as the coordination of the oxo decreases with the μ(3)-oxo on the (311) surface being the least reactive and the η-oxo on the (110)-B surface being the most reactive. A detailed analysis of the electronic changes occurring during water addition on the three sites reveals that this trend is due to both a decrease in the attractive local Madelung potential on the oxo and a decrease in electron withdrawal from the oxo by Co neighbors. Applying a similar electronic structure analysis to the oxidation steps preceding water addition in the catalytic cycle shows that analogous electronic changes occur during this process, explaining a correlation observed between the oxidation potential of a site and its intrinsic reactivity for water addition. This concept is then used to specify criteria for the design of an optimal OER catalyst at a given applied potential. PMID:27108887

  5. Multiplexing oscillatory biochemical signals.

    Science.gov (United States)

    de Ronde, Wiet; ten Wolde, Pieter Rein

    2014-04-01

    In recent years it has been increasingly recognized that biochemical signals are not necessarily constant in time and that the temporal dynamics of a signal can be the information carrier. Moreover, it is now well established that the protein signaling network of living cells has a bow-tie structure and that components are often shared between different signaling pathways. Here we show by mathematical modeling that living cells can multiplex a constant and an oscillatory signal: they can transmit these two signals simultaneously through a common signaling pathway, and yet respond to them specifically and reliably. We find that information transmission is reduced not only by noise arising from the intrinsic stochasticity of biochemical reactions, but also by crosstalk between the different channels. Yet, under biologically relevant conditions more than 2 bits of information can be transmitted per channel, even when the two signals are transmitted simultaneously. These observations suggest that oscillatory signals are ideal for multiplexing signals. PMID:24685537

  6. Clues to tRNA Evolution from the Distribution of Class II tRNAs and Serine Codons in the Genetic Code.

    Science.gov (United States)

    Bernhardt, Harold S

    2016-01-01

    We have previously proposed that tRNA(Gly) was the first tRNA and glycine was the first amino acid incorporated into the genetic code. The next two amino acids incorporated would have been the other two small hydrophilic amino acids serine and aspartic acid, which occurred through the duplication of the tRNA(Gly) sequence, followed by mutation of its anticodon by single C to U transition mutations, possibly through spontaneous deamination. Interestingly, however, tRNA(Ser) has a different structure than most other tRNAs, possessing a long variable arm; because of this tRNA(Ser) is classified as a class II tRNA. Also, serine codons are found not only in the bottom right-hand corner of the genetic code table next to those for glycine and aspartic acid, but also in the top row of the table, next to those for two of the most hydrophobic amino acids, leucine and phenylalanine. In the following, I propose that the class II tRNA structure of tRNA(Ser) and the arrangement of serine codons in the genetic code provide clues to the early evolution of tRNA and the genetic code. In addition, I address Di Giulio's recent criticism of our proposal that tRNA(Gly) was the first tRNA, and discuss how early peptides produced from a restricted amino acid alphabet of glycine, serine and aspartic acid might have possessed proteolytic activity, which is possibly important for the early recycling of amino acid monomers. PMID:26927183

  7. HIV-1 diversity, drug-resistant mutations, and viral evolution among high-risk individuals in phase II HIV vaccine trial sites in southern China.

    Directory of Open Access Journals (Sweden)

    Haiyan Qi

    Full Text Available HIV-1 prevalence in Guangxi, China, has been growing since 1996, when the first case was reported. Over half of HIV-1 positive patients in Guangxi Province were injecting drug users (IDUs, possibly because of the province's location near drug-trafficking routes. Since a phase II HIV vaccine trial is ongoing there, a current characterization of the subtypes of HIV-1 among IDUs in Guangxi would provide critical information for future HIV vaccine trials, as well as further control and prevention of HIV-1 transmission. Thus, we conducted a molecular epidemiological investigation of HIV-1 samples from 2008-2010 among IDUs in multiple cities in Guangxi Province. Our results, based on the gag/pol fragment, indicated a very high proportion (78.47% of HIV-1 CRF08_BC recombinants, some CRF01_AE (15.38% recombinants, and a low proportion of CRF07_BC (6.15% recombinants among the IDUs. The high proportion of CRF08 HIV-1 strains among recent IDUs matches the vaccine candidate constructs. However, future vaccine development should also incorporate CRF01-targeted vaccine candidates. Distinct Env sequence evolution patterns were observed for CRF08_BC and CRF01_AE, indicating that different local selection pressures have been exerted on these two HIV-1 subtypes. Unique drug-resistant mutations were also detected, and our data indicate that HIV treatment programs should consider pre-existing drug-resistant mutations.

  8. Evolution of newly formed dust in Population III supernova remnants and its impact on the elemental composition of Population II.5 stars

    CERN Document Server

    Nozawa, Takaya; Habe, Asao; Dwek, Eli; Umeda, Hideyuki; Tominaga, Nozomu; Maeda, Keiichi; Nomoto, Ken'ichi

    2008-01-01

    We investigate the evolution of dust formed in Population III supernovae (SNe) by considering its transport and processing by sputtering within the SN remnants (SNRs). We find that the fates of dust grains within SNRs heavily depend on their initial radii $a_{\\rm ini}$. For Type II SNRs expanding into the ambient medium with density of $n_{\\rm H,0} = 1$ cm$^{-3}$, grains of $a_{\\rm ini} 0.2$ $\\mu$m are injected into the surrounding medium without being destroyed significantly. Grains with $a_{\\rm ini}$ = 0.05-0.2 $\\mu$m are finally trapped in the dense shell behind the forward shock. We show that the grains piled up in the dense shell enrich the gas up to 10$^{-6}-10^{-4}$ $Z_\\odot$, high enough to form low-mass stars with 0.1-1 $M_\\odot$. In addition, [Fe/H] in the dense shell ranges from -6 to -4.5, which is in good agreement with the ultra-metal-poor stars with [Fe/H] < -4. We suggest that newly formed dust in a Population III SN can have great impacts on the stellar mass and elemental composition of P...

  9. Kinetics of Formation of Cobalt(II)- and Nickel(II) Carbonic Anhydrase.

    Science.gov (United States)

    McQuate, Robert S.; Reardon, John E.

    1978-01-01

    Discusses the kinetic behavior associated with the interaction of metal ions with apocarbonic anhydrase, focusing on the formation of two metallocarbonic anhydrase--the biochemically active Co(II) and the inactive Ni(II)derivatives. (GA)

  10. Biochemical fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, E.; Richter, G.

    1978-03-30

    Until now, biochemical fuel cells have suffered a reduction of capacity in operation due to omission of internal contact between the electrodes and the diaphragm. This disadvantage is remedied by the invention by connecting the oxygen electrode with a rigid electrode frame and providing means for pressing the fuel electrode to the diaphragm and the diaphragm to the oxygen electrode on the side of the fuel electrode away from the diaphragm. The means of exerting pressure can be metal springs, but preferably elastomers, particularly silicon rubber, or springy gels are used.

  11. Biochemical Hypermedia: Galactose Metabolism.

    Directory of Open Access Journals (Sweden)

    J.K. Sugai

    2013-05-01

    Full Text Available Introduction: Animations of biochemical processes and virtual laboratory environments lead to true molecular simulations. The use of interactive software’s in education can improve cognitive capacity, better learning and, mainly, it makes information acquisition easier. Material and Methods: This work presents the development of a biochemical hypermedia to understanding of the galactose metabolism. It was developed with the help of concept maps, ISIS Draw, ADOBE Photoshop and FLASH MX Program. Results and Discussion: A step by step animation process shows the enzymatic reactions of galactose conversion to glucose-1-phosphate (to glycogen synthesis, glucose-6-phosphate (glycolysis intermediary, UDP-galactose (substrate to mucopolysaccharides synthesis and collagen’s glycosylation. There are navigation guide that allow scrolling the mouse over the names of the components of enzymatic reactions of via the metabolism of galactose. Thus, explanatory text box, chemical structures and animation of the actions of enzymes appear to navigator. Upon completion of the module, the user’s response to the proposed exercise can be checked immediately through text box with interactive content of the answer. Conclusion: This hypermedia was presented for undergraduate students (UFSC who revealed that it was extremely effective in promoting the understanding of the theme.

  12. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy. Evolución bioquímica y respuesta histológica de pacientes con hepatitis C bajo tratamiento antiviral.

    Directory of Open Access Journals (Sweden)

    Omar Julián Hernández Ojeda

    2011-07-01

    Full Text Available

    Background: Hepatitis C is a major health problem worldwide and the most common indicator for the need of a liver transplantation in many countries. Objective: To determine the biochemical evolution and the histological response of patients with chronic hepatitis C who were treated with ribavirin and recombinant interferon alfa-2b in the provincial Hepatology consultation. Methods: A descriptive observational study was conducted. It included 31 patients who presented the hepatitis C virus and were treated in the Hepatology consultation of the Provincial General University Hospital of Cienfuegos "Dr. Aldereguía Gustavo Lima’’ from January 2007 to June 2009. These patients were administered with ribavirin and recombinant interferon alfa-2b. Variables such as age, sex, possible route of infection, aminotransferase alanine serum, biochemical evaluation (after treatment and after follow-up and histological response were included. In order to assess the histological activity of chronic liver injuries Knodell Index was used. In order to compare the results (biochemical and histological response before and after treatment the Sign Test was used. Results: Women were predominant in the sample group (58.1%. The average age was 45.5 ± 11.6 years. The possible route of transmission could not be identified in 51.6% of patients, while surgical treatment was identified as the route of infection in 22.6% of the cases, followed by repeated parenteral treatment in 16.1% of them. Conclusion: By the end of treatment there was a higher response rate in terms of biochemical changes and histological response.

  1. Biochemical mechanisms underlying atherogenesis

    Directory of Open Access Journals (Sweden)

    Dr.P.V.L.N. Srinivasa Rao

    2012-02-01

    Full Text Available Atherosclerosis remains one of the major causes of death and premature disability in developed countries. Though atherosclerosis was formerly considered a bland lipid storage disease, substantial advances in basic and experimental sciences have illuminated the role of endothelium, inflammation and immune mechanisms in its pathogenesis. Current concept of atherosclerosis is that of a dynamic and progressive disease arising from in- jury to endothelium, also known as endothelial dysfunction and an inflammatory response to that injury. The lesions of atherosclerosis occur principally in large and medium sized arteries. Atherosclerosis affects various regions of the circulation preferentially and can lead to ischemia of heart, brain or extremities resulting in in- farction.This produces distinct clinical manifestations depending on the vessel involved. Several predisposing factors to cardiovascular diseases such as diabetes mellitus, hypertension, obesity, infections act as triggers to the devel- opment of atherosclerosis by causing endothelial dysfunction and/or promoting inflammatory response. The evolution of pathogenetic mechanisms has passed through various directions such as oxidative stress, inflam- mation and immune responses. It is now known that all these are not acting independently but are interrelated and getting unified in the current concept of atherogenesis. The following discussion aims at providing an in- sight into these developments which can help in a better comprehension of the disease and management of its clinical complications

  2. Estudo comparativo entre estibogluconato de sódio BP 88® e antimoniato de meglumina no tratamento da leishmaniose cutânea II. Toxicidade bioquímica e cardíaca Comparative study between sodium stibogluconate BP 88®and meglumine antimoniate in cutaneous leishmaniasis treatment. II. Biochemical and cardiac toxicity

    Directory of Open Access Journals (Sweden)

    Ana Cristina R. Saldanha

    2000-08-01

    Full Text Available Foi avaliada a toxicidade de dois antimoniais pentavalentes em 111 pacientes com leishmaniose cutânea. Quarenta e sete pacientes receberam antimoniato de meglumina (Grupo I e 64 pacientes, estibogluconato de sódio BP 88® (Grupo II, 20mg SbV/kg/dia por 20 dias. Realizou-se a avaliação de aminotransferases, fosfatase alcalina, amilase, creatinina, uréia, exame de urina e eletrocardiograma, antes do tratamento e no décimo e vigésimo dias. Observou-se maior freqüência de valores anormais de aminotransferases no décimo e vigésimo dias de tratamento no grupo II (p Toxicity of two antimonial pentavalents were evaluated in 111 patients with cutaneous leishmaniasis. Forty seven patients received meglumine antimoniate (Group I and 64 patients, sodium stibogluconate BP 88® (Group II, 20mg SbV/kg/day for 20 days. Evaluation of aminotransferases, alkaline phosphatase, amilase, creatinine, urea, urine analysis and electrocardiogram were performed at baseline, on the tenth and twentieth day of treatment. Greater frequency of aminotransferase abnormal levels were observed on the tenth and twentieth days in group II (p < 0,001 and a greater proportion of amilase abnormal levels at the tenth day in the same group (p < 0,001. There was a greater variation of aminotransferases, alkaline phosphatase and amilase in the first ten days of treatment in group II (p < 0,01. On the twentieth day there was a greater variation of aminotransferase levels in group II (p = 0,02 and p = 0,03, respectively. Forty three percent of group I and 54% of group II showed electrocardiographic abnormalities (p = 0,30.

  3. Biochemical toxicity of benzene.

    Science.gov (United States)

    Rana, S V S; Verma, Yeshvandra

    2005-04-01

    Human exposure to benzene in work environment is a global occupational health problem. After inhalation or absorption, benzene targets organs viz. liver, kidney, lung, heart and brain etc. It is metabolized mainly in the liver by cytochrome P450 multifunctional oxygenase system. Benzene causes haematotoxicity through its phenolic metabolites that act in concert to produce DNA strand breaks, chromosomal damage, sister chromatid exchange, inhibition of topoisomerase II and damage to mitotic spindle. The carcinogenic and myelotoxic effects of benzene are associated with free radical formation either as benzene metabolites or lipid peroxidation products. Benzene oxide and phenol have been considered as proheptons. Liver microsomes play an important role in biotransformation of benzene whereas in kidney, it produces degenerative intracellular changes. Cohort studies made in different countries suggest that benzene induces multiple myeloma in petrochemical workers. Though extensive studies have been performed on its toxicity, endocrinal disruption caused by benzene remains poorly known. Transgenic cytochrome P450 IIE1 mice may help in understanding further toxic manifestations of benzene.

  4. Convergent Evolution of Fern-Specific Mitochondrial Group II Intron atp1i361g2 and Its Ancient Source Paralogue rps3i249g2 and Independent Losses of Intron and RNA Editing among Pteridaceae

    Science.gov (United States)

    Zumkeller, Simon Maria; Knoop, Volker; Knie, Nils

    2016-01-01

    Mitochondrial intron patterns are highly divergent between the major land plant clades. An intron in the atp1 gene, atp1i361g2, is an example for a group II intron specific to monilophytes (ferns). Here, we report that atp1i361g2 is lost independently at least 4 times in the fern family Pteridaceae. Such plant organelle intron losses have previously been found to be accompanied by loss of RNA editing sites in the flanking exon regions as a consequence of genomic recombination of mature cDNA. Instead, we now observe that RNA editing events in both directions of pyrimidine exchange (C-to-U and U-to-C) are retained in atp1 exons after loss of the intron in Pteris argyraea/biaurita and in Actiniopteris and Onychium. We find that atp1i361g2 has significant similarity with intron rps3i249g2 present in lycophytes and gymnosperms, which we now also find highly conserved in ferns. We conclude that atp1i361g2 may have originated from the more ancestral rps3i249g2 paralogue by a reverse splicing copy event early in the evolution of monilophytes. Secondary structure elements of the two introns, most characteristically their domains III, show strikingly convergent evolution in the monilophytes. Moreover, the intron paralogue rps3i249g2 reveals relaxed evolution in taxa where the atp1i361g2 paralogue is lost. Our findings may reflect convergent evolution of the two related mitochondrial introns exerted by co-evolution with an intron-binding protein simultaneously acting on the two paralogues. PMID:27492234

  5. A Comprehensive Analysis of Fermi Gamma-ray Burst Data: II. $E_{\\rm p}$-Evolution Patterns and Implications for the Observed Spectrum-Luminosity Relations

    CERN Document Server

    Lu, Rui-Jing; Liang, En-Wei; Zhang, Bin-Bin; Lü, Hou-Jun; Lian-Zhong,; Lü,; Lei, Wei-Hua; Zhang, Bing

    2012-01-01

    We present a time-resolved spectral analysis of 51 long and 11 short bright GRBs observed with the {\\em Femri}/GBM, paying special attention to $E_{\\rm p}$ evolution within a same burst. Among 8 single-pulse long GRBs, 5 show hard-to-soft evolution, while 3 show intensity-tracking. The multi-pulse long GRBs have more complicated patterns. Among the GRBs whose time-resolved spectrum is available for the first pulse, almost half (15/32 GRBs) show clear hard-to-soft evolution, and the other half (17/32 GRBs) show clear intensity-tracking. Later pulses typically show the tracking behavior, although a hard-to-soft evolution pattern was identified in the 2nd pulse of 2 GRBs whose pulses are well separated. Statistically, the hard-to-soft evolution pulses tend to be more asymmetric than the intensity-tracking ones, with a steeper rising wing than the falling wing. Short GRBs have $E_{\\rm p}$ tracking intensity exclusively with the 16ms time resolution analysis. We performed a simulation analysis, and suggest that at...

  6. Domain structures and molecular evolution of class I and class II major histocompatibility gene complex (MHC) products deduced from amino acid and nucleotide sequence homologies

    Science.gov (United States)

    Ohnishi, Koji

    1984-12-01

    Domain structures of class I and class II MHC products were analyzed from a viewpoint of amino acid and nucleotide sequence homologies. Alignment statistics revealed that class I (transplantation) antigen H chains consist of four mutually homologous domains, and that class II (HLA-DR) antigen β and α chains are both composed of three mutually homologous ones. The N-terminal three and two domains of class I and class II (both β and α) gene products, respectively, all of which being ˜90 residues long, were concluded to be homologous to β2-microglobulin (β2M). The membraneembedded C-terminal shorter domains of these MHC products were also found to be homologous to one another and to the third domain of class I H chains. Class I H chains were found to be more closely related to class II α chains than to class II β chains. Based on these findings, an exon duplication history from a common ancestral gene encoding a β2M-like primodial protein of one-domain-length up to the contemporary MHC products was proposed.

  7. Biochemical assays for the discovery of TDP1 inhibitors

    OpenAIRE

    Marchand, Christophe; Huang, Shar-yin N.; Dexheimer, Thomas S.; Lea, Wendy A.; Mott, Bryan T.; Chergui, Adel; Naumova, Alena; Stephen, Andrew G.; Rosenthal, Andrew S.; Rai, Ganesha; Murai, Junko; Gao, Rui; Maloney, David J.; Jadhav, Ajit; Jorgensen, William L.

    2014-01-01

    Drug screening against novel targets is warranted to generate biochemical probes and new therapeutic drug leads. Tyrosyl-DNA-phosphodiesterases 1 and 2 (TDP1 and TDP2) are two DNA repair enzymes that have yet to be successfully targeted. TDP1 repairs topoisomerase I-, alkylation-, and chain terminator-induced DNA damage, while TDP2 repairs topoisomerase II-induced DNA damage. Here we report the quantitative high-throughput screening (qHTS) of the NIH Molecular Libraries Small Molecule Reposit...

  8. BEST: Biochemical Engineering Simulation Technology

    Energy Technology Data Exchange (ETDEWEB)

    1996-01-01

    The idea of developing a process simulator that can describe biochemical engineering (a relatively new technology area) was formulated at the National Renewable Energy Laboratory (NREL) during the late 1980s. The initial plan was to build a consortium of industrial and U.S. Department of Energy (DOE) partners to enhance a commercial simulator with biochemical unit operations. DOE supported this effort; however, before the consortium was established, the process simulator industry changed considerably. Work on the first phase of implementing various fermentation reactors into the chemical process simulator, ASPEN/SP-BEST, is complete. This report will focus on those developments. Simulation Sciences, Inc. (SimSci) no longer supports ASPEN/SP, and Aspen Technology, Inc. (AspenTech) has developed an add-on to its ASPEN PLUS (also called BioProcess Simulator [BPS]). This report will also explain the similarities and differences between BEST and BPS. ASPEN, developed by the Massachusetts Institute of Technology for DOE in the late 1970s, is still the state-of-the-art chemical process simulator. It was selected as the only simulator with the potential to be easily expanded into the biochemical area. ASPEN/SP, commercially sold by SimSci, was selected for the BEST work. SimSci completed work on batch, fed-batch, and continuous fermentation reactors in 1993, just as it announced it would no longer commercially support the complete ASPEN/SP product. BEST was left without a basic support program. Luckily, during this same time frame, AspenTech was developing a biochemical simulator with its version of ASPEN (ASPEN PLUS), which incorporates most BEST concepts. The future of BEST will involve developing physical property data and models appropriate to biochemical systems that are necessary for good biochemical process design.

  9. Evolution of gaseous disk viscosity driven by supernova explosion. II. Structure and emissions from star-forming galaxies at high redshift

    CERN Document Server

    Yan, Chang-Shuo

    2010-01-01

    (Abridged) High redshift galaxies are undergoing intensive evolution of dynamical structure and morphologies. We incorporate the feedback into the dynamical equations through mass dropout and angular momentum transportation driven by the SNexp-excited turbulent viscosity. We numerically solve the equations and show that there can be intensive evolution of structure of the gaseous disk. Secular evolution of the disk shows interesting characteristics that are 1) high viscosity excited by SNexp can efficiently transport the gas from 10kpc to $\\sim 1$kpc forming a stellar disk whereas a stellar ring forms for the case with low viscosity; 2) starbursts trigger SMBH activity with a lag $\\sim 10^8$yr depending on star formation rates, prompting the joint evolution of SMBHs and bulges; 3) the velocity dispersion is as high as $\\sim 100~\\kms$ in the gaseous disk. In order to compare the present models with the observed dynamical structure and images, we use the incident continuum from the simple stellar synthesis (GAL...

  10. Evolución de parámetros bioquímicos nutricionales en pacientes de hemodiálisis durante un año de seguimiento Evolution of nutritional biochemical parameters in hemodialysis patients during a one-year follow-up period

    Directory of Open Access Journals (Sweden)

    M. Palomares Bayo

    2008-04-01

    dose administered of 1.37 ± 0.27 (KT/V (second generation Daurgidas. A decrease in all the biochemical parameters assessed has been observed, with statistically significant differences: total proteins (p < 0.001, albumin (p < 0.00001, total cholesterol (p < 0.05, and transferrin (p < 0.01. The evolution of the nutritional biochemical parameters assessed showed an important nutritional deterioration of the patients remaining stable with the therapy.

  11. Evolution of Biochemical Parameters During Composting of Various Wastes Compost

    Directory of Open Access Journals (Sweden)

    N. Saidi

    2008-01-01

    Full Text Available In Tunisia the most treatment waste is landfill (50% of wastes were land filled and only 5% are composted. And since our soil become more and more poor in organic matter, green waste can be a significant source of organic matter; in parallel we cited the domestic waste and dead posodonia collected from beaches. All these wastes coming from various origins can be exploited to produce stable compost able to correct the deficiency of soil. Exploiting waste could lead at different quality of mature compost. We are not interested in only the quality of the mature compost but we are interested in the time of the composting cycle. The goals of this study were to characterize the maturity and the sanitary quality of compost in relation with the feed stock source (green waste (C1, green waste mixed with Posidonia (C2 and municipal solid waste (C3. The results obtained showed that the duration of the cycle of composting depends on the nature of the substrate. The longest cycle (200 days was observed with the feed stock source C3. The C/N ratios ranged between 22 and 27 at the beginning of the cycle of composting and decreased notably during time of composting. NH4-N decreased over the progress cycle and at the end of composting progress, all wastes presented a content of NH4-N not exceeding the maximal value recommended for mature compost (400 mg kg-1. The CO2 released by C1 was of approximately 6000 mg C-CO2 DM kg-1 at the start of the cycle and it reached at the end of the cycle of composting 2300 mg C-CO2 DM kg-1. Nevertheless, the deshydrogenase activity (DHA recorded was important during the thermophilous phase at the level of the three piles C1, C2 and C3, where it reached the respective values of 5.9; 6.2 and 4 TPFS/TPF/g of DM. Maturity stage showed the values of 0.3; 0.8 and 0.4 TPFS/TPF/g of DM, respectively. Salmonella appeared only at the level of the piles C2 et C3 at the beginning of composting. After 40th days composting these bacteria are not detected. Staphylocoques were not detected at the level of the two piles C1 and C2. The number of these bacteria was important in the compost C3, where it fluctuated between 103 and 105 bacteria g-1 of dry matter. Statistical analyses showed that the compost of municipal solid waste C3 presented a value of salinity (6.8 g Kg-1 of DM higher than those obtained at the level of the other studied piles 2.6 g kg%/1 of DM for C1; 4 g Kg-1 of DM for C2. We also noted that the compost C2 was relatively rich in P (2.17%/ of DM and MgO (2.62% of DM as compared with the two other studied piles which contain a percentage of MgO of 0. 73 in C1 pile and 0. 8 in C3 pile. Although important heavy metals contents determined in the three studied composts were lower than the levels indicated by the standards of the European Union.

  12. Transcription fluctuation effects on biochemical oscillations.

    Directory of Open Access Journals (Sweden)

    Ryota Nishino

    Full Text Available Some biochemical systems show oscillation. They often consist of feedback loops with repressive transcription regulation. Such biochemical systems have distinctive characteristics in comparison with ordinary chemical systems: i numbers of molecules involved are small, ii there are typically only a couple of genes in a cell with a finite regulation time. Due to the fluctuations caused by these features, the system behavior can be quite different from the one by deterministic rate equations, because the rate equations ignore molecular fluctuations and thus are exact only in the infinite molecular number limit. The molecular fluctuations on a free-running circadian system have been studied by Gonze et al. (2002 by introducing a scale parameter [Formula: see text] for the system size. They consider, however, only the first effect, assuming that the gene process is fast enough for the second effect to be ignored, but this has not been examined systematically yet. Here we study fluctuation effects due to the finite gene regulation time by introducing a new scale parameter [Formula: see text], which we take as the unbinding time of a nuclear protein from the gene. We focus on the case where the fluctuations due to small molecular numbers are negligible. In simulations on the same system studied by Gonze et al., we find the system is unexpectedly sensitive to the fluctuation in the transcription regulation; the period of oscillation fluctuates about 30 min even when the regulation time scale [Formula: see text] is around 30 s, that is even smaller than 1/1000 of its circadian period. We also demonstrate that the distribution width for the oscillation period and amplitude scales with [Formula: see text], and the correlation time scales with [Formula: see text] in the small [Formula: see text] regime. The relative fluctuations for the period are about half of that for the amplitude, namely, the periodicity is more stable than the amplitude.

  13. Hyponatraemia: biochemical and clinical perspectives.

    OpenAIRE

    Gill, G; Leese, G

    1998-01-01

    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 disea...

  14. Evolution and nucleosynthesis of extremely metal-poor and metal-free low- and intermediate-mass stars II. s-process nucleosynthesis during the core He flash

    CERN Document Server

    Campbell, Simon W; Karakas, Amanda I

    2010-01-01

    Models of primordial and hyper-metal-poor stars with masses similar to the Sun experience an ingestion of protons into the hot core during the core helium flash phase at the end of their red giant branch evolution. This produces a concurrent secondary flash powered by hydrogen burning that gives rise to further nucleosynthesis in the core. We perform post-process nucleosynthesis calculations on a one-dimensional stellar evolution calculation of a star of 1 solar mass and metallicity [Fe/H] = -6.5 that suffers a proton ingestion episode. Our network includes 320 nuclear species and 2,366 reactions and treats mixing and burning simultaneously. The mixing and burning of protons into the hot convective core leads to the production of 13C, which then burns via the 13C(alpha,n)16O reaction releasing a large number of free neutrons. During the first two years of neutron production the neutron poison 14N abundance is low, allowing the prodigious production of heavy elements such as strontium, barium, and lead via slo...

  15. Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars

    CERN Document Server

    Fan, X; Brinkmann, J; Fukugita, M; Gunn, J E; Knapp, G R; Richards, G T; Schneider, D P; Strauss, M A; White, R L; Becker, Robert H.; Fan, Xiaohui; Fukugita, Masataka; Gunn, James E.; Knapp, Gillian R.; Richards, Gordon T.; Schneider, Donald P.; Strauss, Michael A.; White, Richard L.

    2005-01-01

    We study the evolution of the ionization state of the IGM at the end of the reionization epoch using spectra of a sample of nineteen quasars at 5.745.7: the optical depth evolution changes from tau ~ (1+z)^{4.3} to (1+z)^{>11}, and the average length of dark gaps with tau>3.5 increases from 80 comoving Mpc. The dispersion of IGM properties along different lines of sight also increases rapidly, implying fluctuations by a factor of >4 in the UV background at z>6, when the mean free path of UV photons is comparable to the correlation length of galaxies. The mean length of dark gaps shows the most dramatic increase at z~6, as well as the largest varianace. We suggest using dark gap statistics as a powerful probe of the ionization state of the IGM at yet higher redshift. The sizes of HII regions around quasars decrease rapidly towards higher redshift, indicating that the neutral fraction of the IGM has increased by a factor of ~14 from z=5.7 to 6.4. The mass-averaged neutral fraction is 1-4% at z~6.2 based on the ...

  16. Biochemical markers of bone turnover

    International Nuclear Information System (INIS)

    Biochemical markers of bone turnover has received increasing attention over the past few years, because of the need for sensitivity and specific tool in the clinical investigation of osteoporosis. Bone markers should be unique to bone, reflect changes of bone less, and should be correlated with radiocalcium kinetics, histomorphometry, or changes in bone mass. The markers also should be useful in monitoring treatment efficacy. Although no bone marker has been established to meet all these criteria, currently osteocalcin and pyridinium crosslinks are the most efficient markers to assess the level of bone turnover in the menopausal and senile osteoporosis. Recently, N-terminal telopeptide (NTX), C-terminal telopeptide (CTX) and bone specific alkaline phosphatase are considered as new valid markers of bone turnover. Recent data suggest that CTX and free deoxypyridinoline could predict the subsequent risk of hip fracture of elderly women. Treatment of postmenopausal women with estrogen, calcitonin and bisphosphonates demonstrated rapid decrease of the levels of bone markers that correlated with the long-term increase of bone mass. Factors such as circadian rhythms, diet, age, sex, bone mass and renal function affect the results of biochemical markers and should be appropriately adjusted whenever possible. Each biochemical markers of bone turnover may have its own specific advantages and limitations. Recent advances in research will provide more sensitive and specific assays

  17. Whither life? Conjectures on the future evolution of biochemistry.

    Science.gov (United States)

    Brewster, Jodi L; Finn, Thomas J; Ramirez, Miguel A; Patrick, Wayne M

    2016-08-01

    Life has existed on the Earth for approximately four billion years. The sheer depth of evolutionary time, and the diversity of extant species, makes it tempting to assume that all the key biochemical innovations underpinning life have already happened. But we are only a little over halfway through the trajectory of life on our planet. In this Opinion piece, we argue: (i) that sufficient time remains for the evolution of new processes at the heart of metabolic biochemistry and (ii) that synthetic biology is providing predictive insights into the nature of these innovations. By way of example, we focus on engineered solutions to existing inefficiencies in energy generation, and on the complex, synthetic regulatory circuits that are currently being implemented. PMID:27555646

  18. Speckle temporal stability in XAO coronagraphic images II. Refine model for quasi-static speckle temporal evolution for VLT/SPHERE

    CERN Document Server

    Martinez, P; Costille, A; Sauvage, J F; Dohlen, K; Puget, P; Beuzit, J L

    2013-01-01

    Observing sequences have shown that the major noise source limitation in high-contrast imaging is due to the presence of quasi-static speckles. The timescale on which quasi-static speckles evolve, is determined by various factors, among others mechanical or thermal deformations. Understanding of these time-variable instrumental speckles, and especially their interaction with other aberrations, referred to as the pinning effect, is paramount for the search of faint stellar companions. The temporal evolution of quasi-static speckles is for instance required for a quantification of the gain expected when using angular differential imaging (ADI), and to determine the interval on which speckle nulling techniques must be carried out. Following an early analysis of a time series of adaptively corrected, coronagraphic images obtained in a laboratory condition with the High-Order Test bench (HOT) at ESO Headquarters, we confirm our results with new measurements carried out with the SPHERE instrument during its final t...

  19. Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ∼ 6 Quasars II: A Sample of 19 Quasars

    International Nuclear Information System (INIS)

    We study the evolution of the ionization state of the intergalactic medium (IGM) at the end of the reionization epoch using moderate resolution spectra of a sample of nineteen quasars at 5.74 em 5.7: the GP optical depth evolution changes from τGPeff ∼ (1 + z)4.3 to (1 + z)∼>11, and the average length of dark gaps with τ > 3.5 increases from 80 comoving Mpc. The dispersion of IGM properties along different lines of sight also increases rapidly, implying fluctuations by a factor of ∼> 4 in the UV background at z > 6, when the mean free path of UV photons is comparable to the correlation length of the star forming galaxies that are thought to have caused reionization. The mean length of dark gaps shows the most dramatic increase at z ∼ 6, as well as the largest line-of-sight variations. We suggest using dark gap statistics as a powerful probe of the ionization state of the IGM at yet higher redshift. The sizes of HII regions around luminous quasars decrease rapidly towards higher redshift, suggesting that the neutral fraction of the IGM has increased by a factor of ∼> 10 from z = 5.7 to 6.4, consistent with the value derived from the GP optical depth. The mass-averaged neutral fraction is 1-4% at z ∼ 6.2 based on the GP optical depth and HII region size measurements. The observations suggest that z ∼ 6 is the end of the overlapping stage of reionization, and are inconsistent with a mostly neutral IGM at z ∼ 6, as indicated by the finite length of dark absorption gaps

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

    Science.gov (United States)

    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.

  1. Biochemical effects of Calotropis procera on hepatotoxicity

    Directory of Open Access Journals (Sweden)

    Ali Ismaiel Ali Abd Alrheam

    2015-12-01

    Full Text Available Introduction: Calotropis procera commonly known as Sodom apple is a 6-meter high shrub that belongs to the Aclepiadaceae plant family and is commonly found in West Africa and other tropical places. In Saudi Arabia the plant is commonly used in traditional medicine for the treatment of variety of diseases including fever, constipation, muscular spasm and joint pain. Aim: In the present study C. procera were investigated for the hepatoprotective activity. Material and Methods: Carbon tetrachloride is used to produce hepatotoxicity. Forty two male albino rats, weighting 150-200 gm divided into seven groups, each consisted of 6 rats. Carbon tetrachloride 2ml/kg was administered twice a week to all of the groups of animals except group I, which served as control and given the normal saline. Group II served as Carbon tetrachloirde control. Group III received Silymarin at 100 mg/kg/day dose, Group IV received aqueous leaves extracts C. procera 200mg/kg, Group V received chloroform leaves extracts C. procera 200mg/kg, Group VI received ethanol leaves extracts C. procera 200 mg/kg, Group VII received latex of C. procera 200mg/kg. The effect of aqueous, chloroform, ethanol leaves extract and latex C. procera on biochemical parameters of liver was measured. Results: The results showed that the aqueous, chloroform, ethanol leaves extract and latex C. procera produced significant decrease in Acid phosphatase, Alkaline phosphatase, Aspartate aminotransferase, Alanine aminotransferase, Total protein, Albumin and total bilirubin levels compared to the CCL4 treated group II. Conclusion: Calotropis procera appears to to have hepatoprotective activity and these may be due to enrich of the plant by phytoconstituents that activate and in hence a pharmacological response of different parts of the body and this study need further studies to shows the complete properties of the plant. [Biomed Res Ther 2015; 2(12.000: 446-453

  2. Biochemical Markers of Myocardial Damage.

    Science.gov (United States)

    Bodor, Geza S

    2016-04-01

    Heart diseases, especially coronary artery diseases (CAD), are the leading causes of morbidity and mortality in developed countries. Effective therapy is available to ensure patient survival and to prevent long term sequelae after an acute ischemic event caused by CAD, but appropriate therapy requires rapid and accurate diagnosis. Research into the pathology of CAD have demonstrated the usefulness of measuring concentrations of chemicals released from the injured cardiac muscle can aid the diagnosis of diseases caused by myocardial ischemia. Since the mid-1950s successively better biochemical markers have been described in research publications and applied for the clinical diagnosis of acute ischemic myocardial injury. Aspartate aminotransferase of the 1950s was replaced by other cytosolic enzymes such as lactate dehydrogenase, creatine kinase and their isoenzymes that exhibited better cardiac specificity. With the availability of immunoassays, other muscle proteins, that had no enzymatic activity, were also added to the diagnostic arsenal but their limited tissue specificity and sensitivity lead to suboptimal diagnostic performance. After the discovery that cardiac troponins I and T have the desired specificity, they have replaced the cytosolic enzymes in the role of diagnosing myocardial ischemia and infarction. The use of the troponins provided new knowledge that led to revision and redefinition of ischemic myocardial injury as well as the introduction of biochemicals for estimation of the probability of future ischemic myocardial events. These markers, known as cardiac risk markers, evolved from the diagnostic markers such as CK-MB or troponins, but markers of inflammation also belong to these groups of diagnostic chemicals. This review article presents a brief summary of the most significant developments in the field of biochemical markers of cardiac injury and summarizes the most recent significant recommendations regarding the use of the cardiac markers in

  3. Enzyme and biochemical producing fungi

    DEFF Research Database (Denmark)

    Lübeck, Peter Stephensen; Lübeck, Mette; Nilsson, Lena;

    2010-01-01

    We are developing a biorefinery concept for biological production of chemicals, drugs, feed and fuels using plant biomass as raw material in well-defined cell-factories. Among the important goals is the discovery of new biocatalysts for production of enzymes, biochemicals and fuels and already our...... screening of a large collection of fungal strains isolated from natural habitats have resulted in identification of strains with high production of hydrolytic enzymes and excretion of organic acids. Our research focuses on creating a fungal platform based on synthetic biology for developing new cell...

  4. Studying the evolution of galaxies in compact groups over the past 3 Gyr - II. The importance of environment in the suppression of star formation

    Science.gov (United States)

    Bitsakis, T.; Dultzin, D.; Ciesla, L.; Díaz-Santos, T.; Appleton, P. N.; Charmandaris, V.; Krongold, Y.; Guillard, P.; Alatalo, K.; Zezas, A.; González, J.; Lanz, L.

    2016-06-01

    We present an in depth study on the evolution of galaxy properties in compact groups over the past 3 Gyr. We are using the largest multiwavelength sample to-date, comprised 1770 groups (containing 7417 galaxies), in the redshift range of 0.01 times). Moreover, their star formation histories as well as their UV-optical and mid-infrared colours are significantly different from those of field and cluster galaxies, indicating that compact group galaxies spend more time transitioning through the green valley. The morphological transformation from late-type spirals to early-type galaxies occurs in the mid-infrared transition zone rather than in the UV-optical green valley. We find evidence of shocks in the emission line ratios and gas velocity dispersions of the late-type galaxies located below the star forming main sequence. Our results suggest that in addition to gas stripping, turbulence and shocks might play an important role in suppressing the star formation in compact group galaxies.

  5. SImulating the LifeCycle of molecular Clouds (SILCC): II. Dynamical evolution of the supernova-driven ISM and the launching of outflows

    CERN Document Server

    Girichidis, Philipp; Naab, Thorsten; Gatto, Andrea; Wünsch, Richard; Glover, Simon C O; Klessen, Ralf S; Clark, Paul C; Peters, Thomas; Derigs, Dominik; Baczynski, Christian

    2015-01-01

    The SILCC project (SImulating the Life-Cycle of molecular Clouds) aims at a more self-consistent understanding of the interstellar medium (ISM) on small scales and its link to galaxy evolution. We present three-dimensional (magneto)hydrodynamic simulations of the ISM in a vertically stratified box including self-gravity, an external potential due to the stellar component of the galactic disc, and stellar feedback in the form of an interstellar radiation field and supernovae (SNe). The cooling of the gas is based on a chemical network that follows the abundances of H+, H, H2, C+, and CO and takes shielding into account consistently. We vary the SN feedback by comparing different SN rates, clustering and different positioning, in particular SNe in density peaks and at random positions, which has a major impact on the dynamics. Only for random SN positions the energy is injected in sufficiently low-density environments to reduce energy losses and enhance the effective kinetic coupling of the SNe with the gas. Th...

  6. Studying the evolution of galaxies in compact groups over the past 3 Gyr - II. The importance of environment in the suppression of star formation

    CERN Document Server

    Bitsakis, T; Ciesla, L; Diaz-Santos, T; Appleton, P; Charmandaris, V; Krongold, Y; Guillard, P; Alatalo, K; Zezas, A; Gonzalez, J; Lanz, L

    2016-01-01

    We present an in depth study on the evolution of galaxy properties in compact groups over the past 3 Gyr. We are using the largest multi-wavelength sample to-date, comprised 1770 groups (containing 7417 galaxies), in the redshift range of 0.01

  7. Surveying the Agents of Galaxy Evolution in the Tidally-Stripped, Low Metallicity Small Magellanic Cloud (SAGE-SMC) II. Cool Evolved Stars

    CERN Document Server

    Boyer, Martha L; van Loon, Jacco Th; McDonald, Iain; Meixner, Margaret; Zaritsky, Dennis; Gordon, Karl D; Kemper, F; Babler, Brian; Block, Miwa; Bracker, Steve; Engelbracht, Charles W; Hora, Joe; Indebetouw, Remy; Meade, Marilyn; Misselt, Karl; Robitaille, Thomas; Sewilo, Marta; Shiao, Bernie; Whitney, Barbara

    2011-01-01

    We investigate the infrared (IR) properties of cool, evolved stars in the Small Magellanic Cloud (SMC), including the red giant branch (RGB) stars and the dust-producing red supergiant (RSG) and asymptotic giant branch (AGB) stars using observations from the Spitzer Space Telescope Legacy program entitled: "Surveying the Agents of Galaxy Evolution in the Tidally-stripped, Low Metallicity SMC", or SAGE-SMC. The survey includes, for the first time, full spatial coverage of the SMC bar, wing, and tail regions at infrared (IR) wavelengths (3.6 - 160 microns). We identify evolved stars using a combination of near-IR and mid-IR photometry and point out a new feature in the mid-IR color-magnitude diagram that may be due to particularly dusty O-rich AGB stars. We find that the RSG and AGB stars each contribute ~20% of the global SMC flux (extended + point-source) at 3.6 microns, which emphasizes the importance of both stellar types to the integrated flux of distant metal-poor galaxies. The equivalent SAGE survey of t...

  8. Asteroid rotation. I - Tabulation and analysis of rates, pole positions and shapes. II - A theory for the collisional evolution of rotation rates

    Science.gov (United States)

    Harris, A. W.; Burns, J. A.

    1979-01-01

    Rotation properties and shape data for 182 asteroids are compiled and analyzed, and a collisional model for the evolution of the mean rotation rate of asteroids is proposed. Tabulations of asteroid rotation rates, taxonomic types, pole positions, sizes and shapes and plots of rotation frequency and light curve amplitude against size indicate that asteroid rotational frequency increases with decreasing size for all asteroids except those of the C or S classes. Light curve data also indicate that small asteroids are more irregular in shape than large asteroids. The dispersion in rotation rates observed is well represented by a three dimensional Maxwellian distribution, suggestive of collisional encounters between asteroids. In the proposed model, the rotation rate is found to tend toward an equilibrium value, at which spin-up due to infrequent, large collisions is balanced by a drag due to the larger number of small collisions. The lower mean rotation rate of C-type asteroids is attributed to a lower means density of that class, and the increase in rotation rate with decreasing size is interpreted as indicative of a substantial population of strong asteroids.

  9. Morphologies of ~190,000 Galaxies at z=0-10 Revealed with HST Legacy Data II. Evolution of Clumpy Galaxies

    CERN Document Server

    Shibuya, Takatoshi; Kubo, Mariko; Harikane, Yuichi

    2015-01-01

    We investigate evolution of clumpy galaxies with the Hubble Space Telescope (HST) samples of ~190,000 photo-z and Lyman break galaxies at z~0-8. We detect clumpy galaxies with off-center clumps in a self-consistent algorithm that is well tested with previous study results, and measure the number fraction of clumpy galaxies at the rest-frame UV, f_clumpy^UV. We identify an evolutionary trend of f_clumpy^UV over z~0-8 for the first time: f_clumpy^UV increases from z~8 to z~1-3 and subsequently decreases from z~1 to z~0, which follows the trend of Madau-Lilly plot. A low average Sersic index of n~1 is found in the underlining components of our clumpy galaxies at z~0-2, indicating that typical clumpy galaxies have disk-like surface brightness profiles. Our f_clumpy^UV values correlate with physical quantities related to star formation activities for star-forming galaxies at z~0-7. We find that clump colors tend to be red at a small galactocentric distance for massive galaxies with log(M_*/M_sun)>~11. All of these...

  10. Carbon-enhanced metal-poor stars: a window on AGB nucleosynthesis and binary evolution. II. Statistical analysis of a sample of 67 CEMP-$s$ stars

    CERN Document Server

    Abate, C; Izzard, R G; Karakas, A I

    2015-01-01

    Many observed CEMP stars are found in binary systems and show enhanced abundances of $s$-elements. The origin of the chemical abundances of these CEMP-$s$ stars is believed to be accretion in the past of enriched material from a primary star in the AGB phase. We investigate the mechanism of mass transfer and the process of nucleosynthesis in low-metallicity AGB stars by modelling the binary systems in which the observed CEMP-$s$ stars were formed. For this purpose we compare a sample of $67$ CEMP-$s$ stars with a grid of binary stars generated by our binary evolution and nucleosynthesis model. We classify our sample CEMP-$s$ stars in three groups based on the observed abundance of europium. In CEMP$-s/r$ stars the europium-to-iron ratio is more than ten times higher than in the Sun, whereas it is lower than this threshold in CEMP$-s/nr$ stars. No measurement of europium is currently available for CEMP-$s/ur$ stars. On average our models reproduce well the abundances observed in CEMP-$s/nr$ stars, whereas in C...

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

    Science.gov (United States)

    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 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.

  12. The spectroscopic evolution of the recurrent nova T Pyxidis during its 2011 outburst. II.The optically thin phase and the structure of the ejecta in recurrent novae

    CERN Document Server

    Shore, S N; Aquino, I De Gennaro; Augusteijn, T; Walter, F M; Starrfield, S; Sion, E M

    2012-01-01

    We continue our study of the physical properties of the recurrent nova T Pyx, focussing on the structure of the ejecta in the nebular stage of expansion during the 2011 outburst. The nova was observed contemporaneously with the Nordic Optical Telescope (NOT), at high resolution spectroscopic resolution (R ~ 65000) on 2011 Oct. 11 and 2012 Apr. 8 (without absolute flux calibration), and with the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope, at high resolution (R ~ 30000) on 2011 Oct. 10 and 2012 Mar. 28 (absolute fluxes). We use standard plasma diagnostics (e.g. [O III] and [N II] line ratios and the H$\\beta$ line fluxes) to constrain electron densities and temperatures. Using Monte Carlo modeling of the ejecta, we derive the structure and filling factor from comparisons to the optical and ultraviolet line profiles. The ejecta can be modeled using an axisymmetric conical -- bipolar -- geometry with a low inclination of the axis to the line of sight, i=15+/-5 degrees, compatible...

  13. Vector Encoding in Biochemical Networks

    Science.gov (United States)

    Potter, Garrett; Sun, Bo

    Encoding of environmental cues via biochemical signaling pathways is of vital importance in the transmission of information for cells in a network. The current literature assumes a single cell state is used to encode information, however, recent research suggests the optimal strategy utilizes a vector of cell states sampled at various time points. To elucidate the optimal sampling strategy for vector encoding, we take an information theoretic approach and determine the mutual information of the calcium signaling dynamics obtained from fibroblast cells perturbed with different concentrations of ATP. Specifically, we analyze the sampling strategies under the cases of fixed and non-fixed vector dimension as well as the efficiency of these strategies. Our results show that sampling with greater frequency is optimal in the case of non-fixed vector dimension but that, in general, a lower sampling frequency is best from both a fixed vector dimension and efficiency standpoint. Further, we find the use of a simple modified Ornstein-Uhlenbeck process as a model qualitatively captures many of our experimental results suggesting that sampling in biochemical networks is based on a few basic components.

  14. SURVEYING THE AGENTS OF GALAXY EVOLUTION IN THE TIDALLY STRIPPED, LOW METALLICITY SMALL MAGELLANIC CLOUD (SAGE-SMC). II. COOL EVOLVED STARS

    International Nuclear Information System (INIS)

    We investigate the infrared (IR) properties of cool, evolved stars in the Small Magellanic Cloud (SMC), including the red giant branch (RGB) stars and the dust-producing red supergiant (RSG) and asymptotic giant branch (AGB) stars using observations from the Spitzer Space Telescope Legacy program entitled 'Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity SMC', or SAGE-SMC. The survey includes, for the first time, full spatial coverage of the SMC bar, wing, and tail regions at IR wavelengths (3.6-160 μm). We identify evolved stars using a combination of near-IR and mid-IR photometry and point out a new feature in the mid-IR color-magnitude diagram that may be due to particularly dusty O-rich AGB stars. We find that the RSG and AGB stars each contribute ∼20% of the global SMC flux (extended + point-source) at 3.6 μm, which emphasizes the importance of both stellar types to the integrated flux of distant metal-poor galaxies. The equivalent SAGE survey of the higher-metallicity Large Magellanic Cloud (SAGE-LMC) allows us to explore the influence of metallicity on dust production. We find that the SMC RSG stars are less likely to produce a large amount of dust (as indicated by the [3.6] - [8] color). There is a higher fraction of carbon-rich stars in the SMC, and these stars appear to reach colors as red as their LMC counterparts, indicating that C-rich dust forms efficiently in both galaxies. A preliminary estimate of the dust production in AGB and RSG stars reveals that the extreme C-rich AGB stars dominate the dust input in both galaxies, and that the O-rich stars may play a larger role in the LMC than in the SMC.

  15. Organizing MHC Class II Presentation

    Directory of Open Access Journals (Sweden)

    David R Fooksman

    2014-04-01

    Full Text Available Major histocompatibility complex (MHC class II molecules are ligands for CD4+ T cells and are critical for initiating the adaptive immune response. This review is focused on what is currently known about MHC class II organization at the plasma membrane of antigen presenting cells and how this affects antigen presentation to T cells. The organization and diffusion of class II molecules have been measured by a variety of biochemical and microscopic techniques. Membrane lipids and other proteins have been implicated in MHC class II organization and function. However, when compared with the organization of MHC class I or TCR complexes, much less is known about MHC class II. Since clustering of T cell receptors occurs during activation, the organization of MHC molecules prior to recognition and during synapse formation may be critical for antigen presentation.

  16. Discuss the Evolution of Japanese Policy towards the Implementation of Advanced Allied War Prisoners During World War II%论二战时期日军对盟军高级战俘奉行政策之演变

    Institute of Scientific and Technical Information of China (English)

    陈春萍

    2015-01-01

    During World War II, the Japanese army attacked Southeast Asia, captured a large number of Unit-ed States, Britain and the Netherlands military senior officials.From the beginning of August 1942, these senior prisoners were transported from their places to Taiwan, and finally transferred to northeast China, was the main re-flection of changes the situation in the Pacific War, and Japanese treatment of prisoners of war policy changes ad-vanced external.This article discussed the relationship between changes and treatment of the Japanese advanced prisoners of war in all period, and the situation of Japanese Pacific war during World War II to summarize the senior prisoner of War pursued the policy evolution.%二战时期,日军在进攻东南亚时,俘虏了大量美国、英国与荷兰的军政高级官员。这些高级战俘从1942年8月开始,从各自被关押地运送到台湾,最后又转押到中国东北。日军频繁变更盟军高级战俘的关押地,主要是太平洋战争局势的变化以及日本对待高级战俘政策变化的外在反映。本文即在探讨日本在各个时期对于高级战俘关押地的变化和待遇与日军太平洋战局的关系,以总结出二战时期日军对高级战俘们所奉行政策的演变过程。

  17. 论二战时期日军对盟军高级战俘奉行政策之演变%Discuss the Evolution of Japanese Policy towards the Implementation of Advanced Allied War Prisoners During World War II

    Institute of Scientific and Technical Information of China (English)

    陈春萍

    2015-01-01

    二战时期,日军在进攻东南亚时,俘虏了大量美国、英国与荷兰的军政高级官员。这些高级战俘从1942年8月开始,从各自被关押地运送到台湾,最后又转押到中国东北。日军频繁变更盟军高级战俘的关押地,主要是太平洋战争局势的变化以及日本对待高级战俘政策变化的外在反映。本文即在探讨日本在各个时期对于高级战俘关押地的变化和待遇与日军太平洋战局的关系,以总结出二战时期日军对高级战俘们所奉行政策的演变过程。%During World War II, the Japanese army attacked Southeast Asia, captured a large number of Unit-ed States, Britain and the Netherlands military senior officials.From the beginning of August 1942, these senior prisoners were transported from their places to Taiwan, and finally transferred to northeast China, was the main re-flection of changes the situation in the Pacific War, and Japanese treatment of prisoners of war policy changes ad-vanced external.This article discussed the relationship between changes and treatment of the Japanese advanced prisoners of war in all period, and the situation of Japanese Pacific war during World War II to summarize the senior prisoner of War pursued the policy evolution.

  18. The SILCC (SImulating the LifeCycle of molecular Clouds) project - II. Dynamical evolution of the supernova-driven ISM and the launching of outflows

    Science.gov (United States)

    Girichidis, Philipp; Walch, Stefanie; Naab, Thorsten; Gatto, Andrea; Wünsch, Richard; Glover, Simon C. O.; Klessen, Ralf S.; Clark, Paul C.; Peters, Thomas; Derigs, Dominik; Baczynski, Christian

    2016-03-01

    The SILCC project (SImulating the Life-Cycle of molecular Clouds) aims at a more self-consistent understanding of the interstellar medium (ISM) on small scales and its link to galaxy evolution. We present three-dimensional (magneto)hydrodynamic simulations of the ISM in a vertically stratified box including self-gravity, an external potential due to the stellar component of the galactic disc, and stellar feedback in the form of an interstellar radiation field and supernovae (SNe). The cooling of the gas is based on a chemical network that follows the abundances of H+, H, H2, C+, and CO and takes shielding into account consistently. We vary the SN feedback by comparing different SN rates, clustering and different positioning, in particular SNe in density peaks and at random positions, which has a major impact on the dynamics. Only for random SN positions the energy is injected in sufficiently low-density environments to reduce energy losses and enhance the effective kinetic coupling of the SNe with the gas. This leads to more realistic velocity dispersions (σ _H I≈ 0.8σ _{300{-}8000 K}˜ 10-20 km s^{-1}, σ _H α ≈ 0.6σ _{8000-3× 10^5 K}˜ 20-30 km s^{-1}), and strong outflows with mass loading factors (ratio of outflow to star formation rate) of up to 10 even for solar neighbourhood conditions. Clustered SNe abet the onset of outflows compared to individual SNe but do not influence the net outflow rate. The outflows do not contain any molecular gas and are mainly composed of atomic hydrogen. The bulk of the outflowing mass is dense (ρ ˜ 10-25-10-24 g cm-3) and slow (v ˜ 20-40 km s-1) but there is a high-velocity tail of up to v ˜ 500 km s-1 with ρ ˜ 10-28-10-27 g cm-3.

  19. The Metal Abundances across Cosmic Time (MACT) Survey. II. Evolution of the Mass-metallicity Relation over 8 Billion Years, Using [OIII]4363AA-based Metallicities

    Science.gov (United States)

    Ly, Chun; Malkan, Matthew A.; Rigby, Jane R.; Nagao, Tohru

    2016-09-01

    We present the first results from MMT and Keck spectroscopy for a large sample of 0.1≤slant z≤slant 1 emission-line galaxies selected from our narrowband imaging in the Subaru Deep Field. We measured the weak [O iii] λ4363 emission line for 164 galaxies (66 with at least 3σ detections, and 98 with significant upper limits). The strength of this line is set by the electron temperature for the ionized gas. Because the gas temperature is regulated by the metal content, the gas-phase oxygen abundance is inversely correlated with [O iii] λ4363 line strength. Our temperature-based metallicity study is the first to span ≈ 8 Gyr of cosmic time and ≈ 3 dex in stellar mass for low-mass galaxies, {log}({M}\\star /{M}⊙ )≈ 6.0-9.0. Using extensive multi-wavelength photometry, we measure the evolution of the stellar mass-gas metallicity relation and its dependence on dust-corrected star formation rate (SFR). The latter is obtained from high signal-to-noise Balmer emission-line measurements. Our mass-metallicity relation is consistent with Andrews & Martini at z≤slant 0.3, and evolves toward lower abundances at a given stellar mass, {log}{({{O/H}})\\propto (1+z)}-{2.32-0.26+0.52}. We find that galaxies with lower metallicities have higher SFRs at a given stellar mass and redshift, although the scatter is large (≈ 0.3 dex) and the trend is weaker than seen in local studies. We also compare our mass-metallicity relation against predictions from high-resolution galaxy formation simulations, and find good agreement with models that adopt energy- and momentum-driven stellar feedback. We identified 16 extremely metal-poor galaxies with abundances of less than a tenth of solar; our most metal-poor galaxy at z≈ 0.84 is similar to I Zw 18.

  20. Biochemical Analysis of Microbial Rhodopsins.

    Science.gov (United States)

    Maresca, Julia A; Keffer, Jessica L; Miller, Kelsey J

    2016-01-01

    Ion-pumping rhodopsins transfer ions across the microbial cell membrane in a light-dependent fashion. As the rate of biochemical characterization of microbial rhodopsins begins to catch up to the rate of microbial rhodopsin identification in environmental and genomic sequence data sets, in vitro analysis of their light-absorbing properties and in vivo analysis of ion pumping will remain critical to characterizing these proteins. As we learn more about the variety of physiological roles performed by microbial rhodopsins in different cell types and environments, observing the localization patterns of the rhodopsins and/or quantifying the number of rhodopsin-bearing cells in natural environments will become more important. Here, we provide protocols for purification of rhodopsin-containing membranes, detection of ion pumping, and observation of functional rhodopsins in laboratory and environmental samples using total internal reflection fluorescence microscopy. © 2016 by John Wiley & Sons, Inc. PMID:27153387

  1. Biochemical bases of mineral waters genesis

    Directory of Open Access Journals (Sweden)

    D. D. Zhernosekov

    2005-02-01

    Full Text Available This work directs data about mineral water genesis. The accent on balneological sense is done. We suggest the criteria of biochemical processes estimation which take part in mineral water compounds creation. These criteria can be used for illustration of dependence between waters medical properties and biochemical processes of their genesis.

  2. Earth's earliest biosphere: Its origin and evolution

    International Nuclear Information System (INIS)

    Some of the subjects discussed are related to the early biogeologic history, the nature of the earth prior to the oldest known rock record, the early earth and the Archean rock record, the prebiotic organic syntheses and the origin of life, Precambrian organic geochemistry, the biochemical evolution of anaerobic energy conversion, the isotopic inferences of ancient biochemistries, Archean stromatolites providing evidence of the earth's earliest benthos, Archean microfossils, the geologic evolution of the Archean-Early Proterozoic earth, and the environmental evolution of the Archean-Early Proterozoic earth. Other topics examined are concerned with geochemical evidence bearing on the origin of aerobiosis, biological and biochemical effects of the development of an aerobic environment, Early Proterozoic microfossils, the evolution of earth's earliest ecosystems, and geographic and geologic data for processed rock samples. Attention is given to a processing procedure for abiotic samples and calculation of model atmospheric compositions, and procedures of organic geochemical analysis

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

    Directory of Open Access Journals (Sweden)

    Lisa M. Bishop

    2010-09-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  5. Biochemical markers for assessment of calcium economy and bone metabolism: application in clinical trials from pharmaceutical agents to nutritional products

    OpenAIRE

    Bonjour, Jean-Philippe; Kohrt, Wendy; Levasseur, Régis; Warren, Michelle; Whiting, Susan; Kraenzlin, Marius

    2014-01-01

    Nutrition plays an important role in osteoporosis prevention and treatment. Substantial progress in both laboratory analyses and clinical use of biochemical markers has modified the strategy of anti-osteoporotic drug development. The present review examines the use of biochemical markers in clinical research aimed at characterising the influence of foods or nutrients on bone metabolism. The two types of markers are: (i) specific hormonal factors related to bone; and (ii) bone turnover markers...

  6. Hunter syndrome in an 11-year old girl on enzyme replacement therapy with idursulfase: brain magnetic resonance imaging features and evolution.

    Science.gov (United States)

    Manara, Renzo; Rampazzo, Angelica; Cananzi, Mara; Salviati, Leonardo; Mardari, Rodica; Drigo, Paola; Tomanin, Rosella; Gasparotto, Nicoletta; Priante, Elena; Scarpa, Maurizio

    2010-12-01

    Mucopolysaccharidosis type II (MPS-II, Hunter disease) is a X-linked recessive disorder. Affected females are extremely rare, mostly due to skewed X chromosome inactivation. A few papers outline MPS-II brain magnetic resonance imaging (MRI) "gestalt" in males, but neuroradiological reports on females are still lacking. We present an 11-year-old girl affected by the severe form of MPS-II who was followed up over a time span of 8 years, focusing on clinical and brain MRI evolution. In the last 2.5 years, the patient has been treated with enzyme replacement therapy (ERT) with idursulfase (Elaprase™, Shire Human Genetic Therapies AB, Sweden). On brain and cervical MRI examination, abnormalities in our patient did not differ from those detected in male patients: J-shaped pituitary sella, enlargement of perivascular spaces, brain atrophy, mild T2-hyperintensity in the paratrigonal white matter, diffuse platyspondylia, and mild odontoid dysplasia with odontoid cup. Brain atrophy progressed despite ERT introduction, whereas perivascular space enlargement did not change significantly before and after ERT. Cognitive impairment worsened independently from the course of white matter abnormality. Despite a profound knowledge of genetic and biochemical aspects in MPS-II, neuroradiology is still poorly characterized, especially in female patients. Spinal and brain involvement and its natural course and evolution after ERT introduction still need to be clarified. PMID:20052546

  7. BIOCHEMICAL SCREENING OF DIABETIC NEPHROPATHY

    Directory of Open Access Journals (Sweden)

    Vivek

    2016-01-01

    Full Text Available Diabetic nephropathy is a clinical syndrome characterized by the following- Persistent albuminuria (>300mg/d or >200μg/min, that is confirmed on at least 2 occasions 3-6 months apart diabetic, progressive decline in the Glomerular Filtration Rate (GFR, elevated arterial blood pressure. The earliest biochemical criteria for the diagnosis of diabetic nephropathy is the presence of micro-albumin in the urine, which if left untreated will eventually lead to End-Stage Renal Disease (ESRD. Micro-albuminuria refers to the excretion of albumin in the urine at a rate that exceeds normal limits. The current study was conducted to establish the prevalence of micro-albuminuria in a sequential sample of diabetic patients attending hospital and OPD Clinic to determine its relationship with known and putative risk factors to identify micro- and normo-albuminuric patients in their sample for subsequent comparison in different age, sex, weight and creatinine clearance of the micro- and normo-albuminuric patients. This cross-sectional analytical study was conducted in one hundred patients at Saraswathi Institute of Medical Sciences, Anwarpur, Hapur, U. P. Patients having diabetes mellitus in different age group ranging from 30 to 70 years were selected. Data was analysed by SPSS software. Micro-albuminuria was observed in 35% in patients with type 2 diabetes mellitus. It was observed that 65% patients were free from any type of albuminuria. Also micro-albuminuria was present in 10% of the patients less than 50 yrs. of age, while 15% of the patients more than 50 yrs. of age were having micro-albuminuria. There was a statistically significant correlation of micro-albuminuria with duration of diabetes. Incidence of micro-albuminuria increases with age as well as increased duration of diabetes mellitus. Our study shows that only 5% patients developed macro-albuminuria. Glycosylated haemoglobin and fasting plasma glucose was significantly raised among all these

  8. Some considerations about evolution of idiopathic primary aldosteronism.

    Science.gov (United States)

    Armanini, D; Fiore, C

    2009-07-01

    The prevalence of primary aldosteronism has increased since many patients who were previously considered as being affected by low renin essential hypertension are actually satisfying the new diagnostic criteria using plasma aldosterone/ plasma renin activity (PRA) ratio. Many of these cases could be classified as subclinical hyperaldosteronism, having normal aldosterone and low PRA, or in alternative the normal range of aldosterone should be revised. Idiopathic hyperaldosteronism can, in many cases, be considered as an evolutive disease: it can be hypothesized that the biochemical picture can be preceded by essential hypertension and that, after several years, primary aldosteronism can evolve back to essential hypertension due to age-related reduced vascular and adrenal sensitivity to angiotensin II. This effect is also evident after longterm treatment with aldosterone receptors blockers and therefore it possible that aldosterone-receptors blockers are able to normalize the sensitivity of glomerulosa to angiotensin II even after long-term withdrawal. The use of aldosterone receptors blockers prevents cardiovascular complications due to local aldosterone effect at the level of endothelium and mononuclear leukocytes; therefore, these drugs should be also considered for therapy of patients with hypertension. It is not excluded that aldosterone receptor blockers could prevent the onset of idiopathic hyperaldosteronism and its complications in patients with hypertension without primary hyperaldosteronism. From all these considerations it follows that the concept of normal range of aldosterone should be revised and the use of aldosterone receptor blockers should be revisited. PMID:19893360

  9. A Program on Biochemical and Biomedical Engineering.

    Science.gov (United States)

    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)

  10. In the light of directed evolution: Pathways of adaptive protein evolution

    OpenAIRE

    Bloom, Jesse D; Arnold, Frances H.

    2009-01-01

    Directed evolution is a widely-used engineering strategy for improving the stabilities or biochemical functions of proteins by repeated rounds of mutation and selection. These experiments offer empirical lessons about how proteins evolve in the face of clearly-defined laboratory selection pressures. Directed evolution has revealed that single amino acid mutations can enhance properties such as catalytic activity or stability and that adaptation can often occur through pathways consisting of s...

  11. A general method for modeling biochemical and biomedical response

    Science.gov (United States)

    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.

  12. 40 CFR 158.2010 - Biochemical pesticides data requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Biochemical pesticides data...) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2010 Biochemical pesticides... required to support registration of biochemical pesticides. Sections 158.2080 through 158.2084 identify...

  13. 40 CFR 158.2000 - Biochemical pesticides definition and applicability.

    Science.gov (United States)

    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...

  14. Silencing, positive selection and parallel evolution: busy history of primate cytochromes C.

    Directory of Open Access Journals (Sweden)

    Denis Pierron

    Full Text Available Cytochrome c (cyt c participates in two crucial cellular processes, energy production and apoptosis, and unsurprisingly is a highly conserved protein. However, previous studies have reported for the primate lineage (i loss of the paralogous testis isoform, (ii an acceleration and then a deceleration of the amino acid replacement rate of the cyt c somatic isoform, and (iii atypical biochemical behavior of human cyt c. To gain insight into the cause of these major evolutionary events, we have retraced the history of cyt c loci among primates. For testis cyt c, all primate sequences examined carry the same nonsense mutation, which suggests that silencing occurred before the primates diversified. For somatic cyt c, maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses yielded the same tree topology. The evolutionary analyses show that a fast accumulation of non-synonymous mutations (suggesting positive selection occurred specifically on the anthropoid lineage root and then continued in parallel on the early catarrhini and platyrrhini stems. Analysis of evolutionary changes using the 3D structure suggests they are focused on the respiratory chain rather than on apoptosis or other cyt c functions. In agreement with previous biochemical studies, our results suggest that silencing of the cyt c testis isoform could be linked with the decrease of primate reproduction rate. Finally, the evolution of cyt c in the two sister anthropoid groups leads us to propose that somatic cyt c evolution may be related both to COX evolution and to the convergent brain and body mass enlargement in these two anthropoid clades.

  15. Chemical evolution and the origin of life

    Science.gov (United States)

    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. Reconfigurable neuromorphic computation in biochemical systems.

    Science.gov (United States)

    Chiang, Hui-Ju Katherine; Jiang, Jie-Hong R; Fages, Francois

    2015-08-01

    Implementing application-specific computation and control tasks within a biochemical system has been an important pursuit in synthetic biology. Most synthetic designs to date have focused on realizing systems of fixed functions using specifically engineered components, thus lacking flexibility to adapt to uncertain and dynamically-changing environments. To remedy this limitation, an analog and modularized approach to realize reconfigurable neuromorphic computation with biochemical reactions is presented. We propose a biochemical neural network consisting of neuronal modules and interconnects that are both reconfigurable through external or internal control over the concentrations of certain molecular species. Case studies on classification and machine learning applications using the DNA strain displacement technology demonstrate the effectiveness of our design in both reconfiguration and autonomous adaptation. PMID:26736417

  17. Single molecule studies of RNA polymerase II transcription in vitro.

    Science.gov (United States)

    Horn, Abigail E; Goodrich, James A; Kugel, Jennifer F

    2014-01-01

    Eukaryotic mRNA transcription by RNA polymerase II (RNAP II) is the first step in gene expression and a key determinant of cellular regulation. Elucidating the mechanism by which RNAP II synthesizes RNA is therefore vital to determining how genes are controlled under diverse biological conditions. Significant advances in understanding RNAP II transcription have been achieved using classical biochemical and structural techniques; however, aspects of the transcription mechanism cannot be assessed using these approaches. The application of single-molecule techniques to study RNAP II transcription has provided new insight only obtainable by studying molecules in this complex system one at a time.

  18. Stellar evolution

    CERN Document Server

    Meadows, A J

    2013-01-01

    Stellar Evolution, Second Edition covers the significant advances in the understanding of birth, life, and death of stars.This book is divided into nine chapters and begins with a description of the characteristics of stars according to their brightness, distance, size, mass, age, and chemical composition. The next chapters deal with the families, structure, and birth of stars. These topics are followed by discussions of the chemical composition and the evolution of main-sequence stars. A chapter focuses on the unique features of the sun as a star, including its evolution, magnetic fields, act

  19. 2009 Biochemical Conversion Platform Review Report

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, John [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    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.

  20. Biochemical Thermodynamics under near Physiological Conditions

    Science.gov (United States)

    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…

  1. Biochemical Applications in the Analytical Chemistry Lab

    Science.gov (United States)

    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…

  2. Biochemical applications of FT-IR spectroscopy

    NARCIS (Netherlands)

    Pistorius, A.M.A.

    1996-01-01

    This thesis describes the use of (FT-)IR spectroscopy in general biochemical research. In chapter 3, IR spectroscopy is used in the quantitation of residual detergent after reconstitution of an integral membrane protein in a pre-defined lipid matrix. This chapter discusses the choice of the vibratio

  3. Characterizing multistationarity regimes in biochemical reaction networks.

    Directory of Open Access Journals (Sweden)

    Irene Otero-Muras

    Full Text Available Switch like responses appear as common strategies in the regulation of cellular systems. Here we present a method to characterize bistable regimes in biochemical reaction networks that can be of use to both direct and reverse engineering of biological switches. In the design of a synthetic biological switch, it is important to study the capability for bistability of the underlying biochemical network structure. Chemical Reaction Network Theory (CRNT may help at this level to decide whether a given network has the capacity for multiple positive equilibria, based on their structural properties. However, in order to build a working switch, we also need to ensure that the bistability property is robust, by studying the conditions leading to the existence of two different steady states. In the reverse engineering of biological switches, knowledge collected about the bistable regimes of the underlying potential model structures can contribute at the model identification stage to a drastic reduction of the feasible region in the parameter space of search. In this work, we make use and extend previous results of the CRNT, aiming not only to discriminate whether a biochemical reaction network can exhibit multiple steady states, but also to determine the regions within the whole space of parameters capable of producing multistationarity. To that purpose we present and justify a condition on the parameters of biochemical networks for the appearance of multistationarity, and propose an efficient and reliable computational method to check its satisfaction through the parameter space.

  4. Schumpeter's Evolution

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    reworking of his basic theory of economic evolution in Development from 1934, and this reworking was continued in Cycles from 1939. Here Schumpeter also tried to handle the statistical and historical evidence on the waveform evolution of the capitalist economy. Capitalism from 1942 modified the model...... originally developed his evolutionary research programme in Wesen from 1908 by studying the inherent limitations of Neoclassical Economics. He presented core results on economic evolution and sketched an extension evolutionary analysis to all social sciences in Entwicklung from 1912. He made a partial...... of economic evolution and added evolutionary contributions to other social sciences. History, which was published by his widow, was based on his evolutionary theory of the history of economic analysis. This sequential analysis of Schumpeter's six books demonstrates the progress he within his research...

  5. Evolution of seismic monitoring systems of nuclear power plants. Improvements and practical applications; Evolucion de los sistemas de vigilancia sismica de las II.NN. Mejoras introducidas y aplicaciones practicas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Cabanero, J. G.; Jimenez Juan, A.

    2010-07-01

    The II. NN. Spanish have a seismic monitoring system (SVS) covering two objectives relevant to nuclear security: determining earthquake leave operation, and specific data that serve to limit or reduce the uncertainties associated with the seismic source, the site and design. Since its construction, the major SVS II. NN. have been equipped with the best time of seismic instrumentation to record earthquakes strong, but with limited resolution for recording in the free field and appropriately moderate earthquakes.

  6. Tyrosine aminotransferase: biochemical and structural properties and molecular dynamics simulations

    Energy Technology Data Exchange (ETDEWEB)

    Mehere, P.; Robinson, H.; Han, Q.; Lemkul, J. A.; Vavricka, C. J.; Bevan, D. R.; Li, J.

    2010-11-01

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using {alpha}-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 {angstrom} resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  7. Tyrosine Aminotransferase: Biochemical and Structural Properties and Molecular Dynamics Simulations

    Energy Technology Data Exchange (ETDEWEB)

    P Mehere; Q Han; J Lemkul; C Vavricka; H Robinson; D Bevan; J Li

    2011-12-31

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using {alpha}-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 {angstrom} resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  8. Tyrosine aminotransferase: biochemical and structural properties and molecular dynamics simulations.

    Science.gov (United States)

    Mehere, Prajwalini; Han, Qian; Lemkul, Justin A; Vavricka, Christopher J; Robinson, Howard; Bevan, David R; Li, Jianyong

    2010-11-01

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using α-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 Å resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  9. The fine details of evolution.

    Science.gov (United States)

    Laskowski, Roman A; Thornton, Janet M; Sternberg, Michael J E

    2009-08-01

    Charles Darwin's theory of evolution was based on studies of biology at the species level. In the time since his death, studies at the molecular level have confirmed his ideas about the kinship of all life on Earth and have provided a wealth of detail about the evolutionary relationships between different species and a deeper understanding of the finer workings of natural selection. We now have a wealth of data, including the genome sequences of a wide range of organisms, an even larger number of protein sequences, a significant knowledge of the three-dimensional structures of proteins, DNA and other biological molecules, and a huge body of information about the operation of these molecules as systems in the molecular machinery of all living things. This issue of Biochemical Society Transactions contains papers from oral presentations given at a Biochemical Society Focused Meeting to commemorate the 200th Anniversary of Charles Darwin's birth, held on 26-27 January 2009 at the Wellcome Trust Conference Centre, Cambridge. The talks reported on some of the insights into evolution which have been obtained from the study of protein sequences, structures and systems. PMID:19614583

  10. The evolution of transcriptional regulation in eukaryotes

    Science.gov (United States)

    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.

  11. Cytologic-Biochemical Radiation Dosimeters in Man

    International Nuclear Information System (INIS)

    The result of radiation interacting with living tissue is the deposition of energy therein. This energy triggers numerous chemical reactions within the molecules of the target tissues. We have measured in man the results of some of these reactions at doses up to 300 rads: chromosome aberrations; alterations in the kinetics of specific human cell populations; changes in 37 biochemical constituents of serum and/or urine. The utilization of chromosomes as a biological dosimeter is partially perfected but there are numerous discrepancies in data between different laboratories. Etiocholanolone can be used to evaluate marrow injury before the white-cell count falls below 5000/mm3. Most biochemical dosimeters evaluated gave negative or inconsistent results. However, salivary amylase is a promising indicator of human radiation injury from doses as low as 100 rads. (author)

  12. Optical Biochemical Platforms for Nanoparticles Detection

    CERN Document Server

    Campanella, Clarissa Martina

    2014-01-01

    In the biochemical sensing field, a fervent research activity related to the development of real time, low cost, compact and high throughput devices for the detection and characterization of natural or synthetic nanoparticles NPs actually exists. In this research scenario, different platforms for biosensing purposes have been developed according to the huge amount of physical effects involved in the transduction of the biochemical-signal into a measurable output signal. In the present work two different optical platforms for NP detection have been investigated, one based on integrated optics and the other based on microscopy. Both the approaches rely on the study of the interaction of an electromagnetic wave with a small particle in the hypothesis of dealing with a Rayleigh scatterer, i.e. a nanoparticle having a size really smaller than the one of the wavelength of the incident light and scattering light elastically.

  13. Advancement in biochemical assays in andrology

    Institute of Scientific and Technical Information of China (English)

    Wolf-BernhardSchill; RaftHenkel

    1999-01-01

    Determination of maikers of sperm function, accessory sex gland secretion and silent male genital tract inflammation is of considerable diagnostic value in the evaluation of male infertility. The introduction of biochemical tests into the analysis of male factor has the advantage that standardized assays with a coefficient of variafion characteristic of clinical chemistry are performed, in contrast to biological test systems with a large variability .Biochemical parameters may be used in clinical practice to evaluate the sperm fertitizing capacity (acrosin, aniline blue,ROS), to characterize male accessory sex gland secretinns (fructose, a-glucosidase, PSA), and to identify men with silent genital tract inflammation (elastase, C'3 complement component, coeruloplasmin, IgA, IgG, ROS). (As/an J Androl 1999 Jun; 1: 45-51)

  14. RNA polymerase II collision interrupts convergent transcription

    DEFF Research Database (Denmark)

    Hobson, David J; Wei, Wu; Steinmetz, Lars M;

    2012-01-01

    Antisense noncoding transcripts, genes-within-genes, and convergent gene pairs are prevalent among eukaryotes. The existence of such transcription units raises the question of what happens when RNA polymerase II (RNAPII) molecules collide head-to-head. Here we use a combination of biochemical...... genes. These results provide insight into fundamental mechanisms of gene traffic control and point to an unexplored effect of antisense transcription on gene regulation via polymerase collision....

  15. Prions: the danger of biochemical weapons

    OpenAIRE

    Eric Almeida Xavier

    2014-01-01

    The knowledge of biotechnology increases the risk of using biochemical weapons for mass destruction. Prions are unprecedented infectious pathogens that cause a group of fatal neurodegenerative diseases by a novel mechanism. They are transmissible particles that are devoid of nucleic acid. Due to their singular characteristics, Prions emerge as potential danger since they can be used in the development of such weapons. Prions cause fatal infectious diseases, and to date there is no therapeutic...

  16. The stochastic dynamics of biochemical systems

    OpenAIRE

    Challenger, Joseph Daniel

    2013-01-01

    The topic of this thesis is the stochastic dynamics of biochemical reaction systems. The importance of the intrinsic fluctuations in these systems has become more widely appreciated in recent years, and should be accounted for when modelling such systems mathematically. These models are described as continuous time Markov processes and their dynamics defined by a master equation. Analytical progress is made possible by the use of the van Kampen system-size expansion, which splits the dynamics...

  17. TBscore II

    DEFF Research Database (Denmark)

    Rudolf, Frauke; Lemvik, Grethe; Abate, Ebba;

    2013-01-01

    Abstract Background: The TBscore, based on simple signs and symptoms, was introduced to predict unsuccessful outcome in tuberculosis patients on treatment. A recent inter-observer variation study showed profound variation in some variables. Further, some variables depend on a physician assessing...... them, making the score less applicable. The aim of the present study was to simplify the TBscore. Methods: Inter-observer variation assessment and exploratory factor analysis were combined to develop a simplified score, the TBscore II. To validate TBscore II we assessed the association between start...

  18. Electronic modulation of biochemical signal generation

    Science.gov (United States)

    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.

  19. Haematological and biochemical analysis in canine enteritis

    Directory of Open Access Journals (Sweden)

    Abid Ali Bhat

    Full Text Available Aim: The present investigation screened eighteen clinical cases of canine enteritis for haematological and biochemical analyses. Materials and Methods: Eighteen dogs suffering from enteritis were selected and detailed clinical manifestations were noted. Hematological and biochemical parameters were estimated by using various kits. Blood was also collected from twelve healthy dogs for establishing control values and data obtained were subjected to statistical analysis. Results: The affected dogs showed anorexia, diarrhoea, depression, varying degree of dehydration and tachycardia. There were significant changes in packed cell volume, neutrophils, lymphocytes and mean corpuscular haemoglobin concentration. Biochemical investigation revealed significant decrease in plasma glucose, total plasma protein, albumin and albumin:globulin ratio (A:G ratio. The level of potassium and chloride was markedly decreased. Significant increase in alanine aminotransferase (ALT and blood urea nitrogen (BUN was observed. Conclusion: Packed Cell Volume (PCV and Total Erythrocyte Count (TEC remained almost similar between healthy dogs and dogs affected with diarrhoea. Mean Total Leukocyte Count (TLC value was significantly higher as compared to the control group. Hypoglycemia, hypoproteinemia, hypokalemia, hypochloremia and increase in blood urea nitrogen was observed in dogs suffering from enteritis. [Vet World 2013; 6(7.000: 380-383

  20. [Biochemical antenatal screening for fetal anomalies.].

    Science.gov (United States)

    Torfadóttir, G; Jónsson, J J

    2001-05-01

    Biochemical antenatal screening started 30 years ago. Initially, the goal was to detect neural tube defects by measuring a-fetoprotein in maternal serum (MS-AFP) and amniotic fluid (AF-AFP). The serendipitous discovery of an association between low AFP maternal serum concentration and chromosomal anomalies resulted in increased research interest in biochemical screening in pregnancy. Subsequently double, triple or quadruple tests in 2nd trimester of pregnancy became widely used in combination with fetal chromosome determination in at risk individuals. In Iceland, antenatal screening for chromosomal anomalies has essentially been based on fetal chromosome studies offered to pregnant women 35 years or older. This strategy needs to be revised. Recently first trimester biochemical screening based on maternal serum pregnancy associated plasma protein A (MS-PAPP-A) and free b-human chorionic gonadotropin (MS-free b-hCG) and multivariate risk assessment has been developed. This screening test can be improved if done in conjunction with nuchal translucency measurements in an early sonography scan. PMID:17018982

  1. Hydrogel-based piezoresistive biochemical microsensors

    Science.gov (United States)

    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.

  2. Biochemical reaction engineering for redox reactions.

    Science.gov (United States)

    Wandrey, Christian

    2004-01-01

    Redox reactions are still a challenge for biochemical engineers. A personal view for the development of this field is given. Cofactor regeneration was an obstacle for quite some time. The first technical breakthrough was achieved with the system formate/formate dehydrogenase for the regeneration of NADH2. In cases where the same enzyme could be used for chiral reduction as well as for cofactor regeneration, isopropanol as a hydrogen source proved to be beneficial. The coproduct (acetone) can be removed by pervaporation. Whole-cell reductions (often yeast reductions) can also be used. By proper biochemical reaction engineering, it is possible to apply these systems in a continuous way. By cloning a formate dehydrogenase and an oxidoreductase "designer bug" can be obtained where formate is used instead of glucose as the hydrogen source. Complex sequences of redox reactions can be established by pathway engineering with a focus on gene overexpression or with a focus on establishing non-natural pathways. The success of pathway engineering can be controlled by measuring cytosolic metabolite concentrations. The optimal exploitation of such systems calls for the integrated cooperation of classical and molecular biochemical engineering.

  3. Representing Evolution

    DEFF Research Database (Denmark)

    Hedin, Gry

    2012-01-01

    . This article discusses Willumsen's etching in the context of evolutionary theory, arguing that Willumsen is a rare example of an artist who not only let the theory of evolution fuel his artistic imagination, but also concerned himself with a core issue of the theory, namely to what extent it could be applied...

  4. Evolution des donnees maternelles et perinatales recueillies en routine entre 1980 et 1998 a la maternite de reference de Rutshuru en Republique democratique du Congo. II. Deces du nouveau-ne et naissances de faible poids.

    OpenAIRE

    Mugisho, Etienne; Dramaix, Michele; Porignon, Denis; Musubao, Ernest; Hennart, Philippe

    2002-01-01

    This second paper aims at deriving useful information allowing to improve the strategy applied for maternal health care. MATERIAL AND METHODOLOGY: Between 1980 and 1998, data on 13,042 deliveries were collected. Characteristics, mortality, morbidity of mothers and new-born and obstetrical interventions were recorded. The present work describes the evolution of low birth weight (LBW), new-born deaths, and associated risk factors. The statistical analyses applied included khi2, t-test, and mult...

  5. BNDB – The Biochemical Network Database

    Directory of Open Access Journals (Sweden)

    Kaufmann Michael

    2007-10-01

    Full Text Available Abstract Background Technological advances in high-throughput techniques and efficient data acquisition methods have resulted in a massive amount of life science data. The data is stored in numerous databases that have been established over the last decades and are essential resources for scientists nowadays. However, the diversity of the databases and the underlying data models make it difficult to combine this information for solving complex problems in systems biology. Currently, researchers typically have to browse several, often highly focused, databases to obtain the required information. Hence, there is a pressing need for more efficient systems for integrating, analyzing, and interpreting these data. The standardization and virtual consolidation of the databases is a major challenge resulting in a unified access to a variety of data sources. Description We present the Biochemical Network Database (BNDB, a powerful relational database platform, allowing a complete semantic integration of an extensive collection of external databases. BNDB is built upon a comprehensive and extensible object model called BioCore, which is powerful enough to model most known biochemical processes and at the same time easily extensible to be adapted to new biological concepts. Besides a web interface for the search and curation of the data, a Java-based viewer (BiNA provides a powerful platform-independent visualization and navigation of the data. BiNA uses sophisticated graph layout algorithms for an interactive visualization and navigation of BNDB. Conclusion BNDB allows a simple, unified access to a variety of external data sources. Its tight integration with the biochemical network library BN++ offers the possibility for import, integration, analysis, and visualization of the data. BNDB is freely accessible at http://www.bndb.org.

  6. PORT II

    Science.gov (United States)

    Muniz, Beau

    2009-01-01

    One unique project that the Prototype lab worked on was PORT I (Post-landing Orion Recovery Test). PORT is designed to test and develop the system and components needed to recover the Orion capsule once it splashes down in the ocean. PORT II is designated as a follow up to PORT I that will utilize a mock up pressure vessel that is spatially compar able to the final Orion capsule.

  7. Cleavage of recombinant proteins at poly-His sequences by Co(II) and Cu(II)

    OpenAIRE

    Andberg, Martina; Jäntti, Jussi; Heilimo, Sara; Pihkala, Päivi; Paananen, Arja; Koskinen, Ari M P; Söderlund, Hans; Linder, Markus B

    2007-01-01

    Improved ways to cleave peptide chains at engineered sites easily and specifically would form useful tools for biochemical research. Uses of such methods include the activation or inactivation of enzymes or the removal of tags for enhancement of recombinant protein expression or tags used for purification of recombinant proteins. In this work we show by gel electrophoresis and mass spectroscopy that salts of Co(II) and Cu(II) can be used to cleave fusion proteins specifically at sites where s...

  8. Biochemical Disincentives to Fertilizing Cellulosic Ethanol Crops

    Science.gov (United States)

    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

  9. Radiation treatment of drugs, biochemicals and vaccines

    International Nuclear Information System (INIS)

    The concise and tabulated review reports experimental results on the effects of radiation treatment on drugs, vaccines, biochemicals and adjuvants including enzymes as well. Irradiation was mostly performed by γ-radiation using 60Co and to a lesser extent by 137Cs, 182Ta, X-rays and accelerators. Ionizing radiation proved to be a useful tool for sterilization and inactivation in producing drugs, vaccines, and bioactive agents and will contribute to realize procedures difficultly solvable as to engineering and economy, respectively. 124 refs

  10. Induced biochemical conversions of heavy crude oils

    International Nuclear Information System (INIS)

    Products formed during multiple interactions of microorganisms with oils fall into two major categories: those formed due to the action of indigenous microorganisms under reservoir conditions over geological periods of time and those products which are generated by the action of introduced organisms. The extreme end product of the first category is the production of heavy 'biodegraded' crudes. The extreme end product of the second category is the production of reduced sulfates due to the introduction of sulfate-reducing bacteria which may lead to the souring of a field. There is, however, a select group of microorganisms whose action on the crudes is beneficial. The interactions between such microorganisms and different crude oils occur through complex biochemical and chemical reactions. These reactions depend on multiple variables within and at the interface of a multicomponent system consisting of organic, aqueous, and inorganic components. Studies, carried out in this laboratory (BNL) of biochemical and chemical reactions in crude oils which involve extremophilic organisms (organisms which thrive in extreme environments), have shown that the reactions are not random and follow distinct trends. These trends can be categorized. The use of a group of characteristic chemical markers, such as mass spectrometric fragmentation patterns of light and heavy hydrocarbons, heterocyclic and organometallic compounds, as well as total trace metal and heteroatom contents of crude oils before and after the biochemical treatment allows to follow the type and the extent of chemical changes which occur during the biochemical conversion of heavy crude oils by microorganisms. The bioconversion involves multiple, simultaneous, and/or concurrent chemical reactions in which the microorganisms serve as biocatalysts. In this sense, the biocatalysts are active in a reaction medium which depends on the chemical composition of the crude and the selectivity of the biocatalyst. Thus, the

  11. [Fe]-hydrogenases in green algae: photo-fermentation and hydrogen evolution under sulfur deprivation

    Energy Technology Data Exchange (ETDEWEB)

    Winkler, M.; Hemschemeier, A.; Happe, T. [Botanisches Institut der Universitat Bonn (Germany); Gotor, C. [CSIC y Universidad de Sevilla (Spain). Instituto de Bioquimica Vegetal y Fotosintesis; Melis, A. [University of California, Berkeley, CA (United States). Department of Plant and Microbial Biology

    2002-12-01

    Recent studies indicate that [Fe]-hydrogenases and H{sub 2} metabolism are widely distributed among green algae. The enzymes are simple structured and catalyze H{sub 2} evolution with similar rates than the more complex [Fe]-hydrogenases from bacteria. Different green algal species developed diverse strategies to survive under sulfur deprivation. Chlamydomonas reinhardtii evolves large quantities of hydrogen gas in the absence of sulfur. In a sealed culture of C. reinhardtii, the photosynthetic O{sub 2} evolution rate drops below the rate of respiratory O{sub 2} consumption due to a reversible inhibition of photosystem II, thus leading to an intracellular anaerobiosis. The algal cells survive under these anaerobic conditions by switching their metabolism to a kind of photo-fermentation. Although possessing a functional [Fe]-hydrogenase gene, the cells of Scenedesmus obliquus produce no significant amounts of H{sub 2} under S-depleted conditions. Biochemical analyses indicate that S. obliquus decreases almost the complete metabolic activities while maintaining a low level of respiratory activity. (author)

  12. The Chemodynamical Evolution of Galaxies

    Science.gov (United States)

    Gibson, Brad K.; Kawata, Daisuke; Brook, Chris B.; Connors, Tim W.

    GCD+ (Galactic Chemodynamics Plus) is a soon-to-be publically available N-body/SPH code being developed at Swinburne University for modeling the formation and evolution of galaxies within a cosmological framework. A sophisticated chemical evolution module as been incorporated within GCD+ making use of the latest stellar yields on the market; a self-consistent treatment of energy feedback from Type Ia and II supernovae (relaxing the instantaneous recycling approximation) cooling and star formation is standard within GCD+. Spatially resolved synthetic maps can be generated ranging from stellar populations to the hot and warm X-ray emitting properties of clusters. We will demonstrate GCD+'s application to simulating the 7-dimensional phase space (position velocity chemistry) distribution of the oldest stars in the Milky Way in addition to its seemless predictive power in regards to spatial and temporal evolution of the age-metallicty relationship metallicity distribution functions and the disruption of the Magellanic System

  13. Recent progress in the crystallographic studies of photosystem II

    NARCIS (Netherlands)

    Guskov, Albert; Gabdulkhakov, Azat; Broser, Matthias; Glöckner, Carina; Hellmich, Julia; Kern, Jan; Frank, Joachim; Müh, Frank; Saenger, Wolfram; Zouni, Athina

    2010-01-01

    The photosynthetic oxygen-evolving photosystem II (PSII) is the only known biochemical system that is able to oxidize water molecules and thereby generates almost all oxygen in the Earth's atmosphere. The elucidation of the structural and mechanistic aspects of PSII keeps scientists all over the wor

  14. PsbQ (Sll1638) in Synechocystis sp. PCC 6803 is required for photosystem II activity in specific mutants and in nutrient-limiting conditions.

    Science.gov (United States)

    Summerfield, Tina C; Shand, Jackie A; Bentley, Fiona K; Eaton-Rye, Julian J

    2005-01-18

    A PsbQ homologue has been found associated with photosystem II complexes in Synechocystis sp. PCC 6803 where it is involved in optimal photoautotrophic growth and water splitting under CaCl(2)-depleted conditions [Thornton, L. E., Ohkawa, H., Roose, J. L., Kashino, Y., Keren, N., and Pakrasi, H. B. (2004) Plant Cell 16, 2164-2175]. By inactivating psbQ in strains carrying photosystem II-specific mutations, we have identified stringent requirements for PsbQ in vivo. Whereas under nutrient-replete conditions the DeltaPsbQ mutant was similar to wild type, a strain lacking PsbQ and PsbV was not photoautotrophic, exhibiting decreased oxygen evolution and decreased photosystem II assembly compared to the DeltaPsbV mutant. Combining the removal of PsbU and PsbQ introduced an altered requirement for Ca(2+) and Cl(-), and photoautotrophic growth of the DeltaPsbQ strain was prevented in nutrient-limiting media depleted in Ca(2+), Cl(-), and iron. Unlike other photosystem II extrinsic proteins PsbQ did not participate in the acquisition of thermotolerance; however, photoautotrophic growth at elevated temperatures was impaired in this mutant. Growth of the DeltaPsbV:DeltaPsbQ mutant was restored at pH 10.0: in contrast, an additional deletion between Arg-384 and Val-392 in the CP47 protein of photosystem II prevented recovery at alkaline pH. When conditions prevented photoautotrophy in strains lacking PsbQ, photoheterotrophic growth was indistinguishable to wild type, indicating that photosystem II had been inactivated. These data substantiate a role for PsbQ in optimizing photosystem II activity in Synechocystis sp. PCC 6803 and establish an absolute requirement for the subunit under specific biochemical and physiological conditions. PMID:15641809

  15. Ubiquitination by March-I prevents MHC class II recycling and promotes MHC class II turnover in antigen-presenting cells.

    Science.gov (United States)

    Cho, Kyung-Jin; Walseng, Even; Ishido, Satoshi; Roche, Paul A

    2015-08-18

    MHC class II (MHC-II)-dependent antigen presentation by antigen-presenting cells (APCs) is carefully controlled to achieve specificity of immune responses; the regulated assembly and degradation of antigenic peptide-MHC-II complexes (pMHC-II) is one aspect of such control. In this study, we have examined the role of ubiquitination in regulating pMHC-II biosynthesis, endocytosis, recycling, and turnover in APCs. By using APCs obtained from MHC-II ubiquitination mutant mice, we find that whereas ubiquitination does not affect pMHC-II formation in dendritic cells (DCs), it does promote the subsequent degradation of newly synthesized pMHC-II. Acute activation of DCs or B cells terminates expression of the MHC-II E3 ubiquitin ligase March-I and prevents pMHC-II ubiquitination. Most importantly, this change results in very efficient pMHC-II recycling from the surface of DCs and B cells, thereby preventing targeting of internalized pMHC-II to lysosomes for degradation. Biochemical and functional assays confirmed that pMHC-II turnover is suppressed in MHC-II ubiquitin mutant DCs or by acute activation of wild-type DCs. These studies demonstrate that acute APC activation blocks the ubiquitin-dependent turnover of pMHC-II by promoting efficient pMHC-II recycling and preventing lysosomal targeting of internalized pMHC-II, thereby enhancing pMHC-II stability for efficient antigen presentation to CD4 T cells.

  16. Microbiological and Biochemical Characterization of Cassava Retting, a Traditional Lactic Acid Fermentation for Foo-Foo (Cassava Flour) Production

    OpenAIRE

    Brauman, A.; Keleke, S.; Malonga, M.; Miambi, E.; Ampe, F

    1996-01-01

    The overall kinetics of retting, a spontaneous fermentation of cassava roots performed in central Africa, was investigated in terms of microbial-population evolution and biochemical and physicochemical parameters. During the traditional process, endogenous cyanogens were almost totally degraded, plant cell walls were lysed by the simultaneous action of pectin methylesterase and pectate lysate, and organic acids (C2 to C4) were produced. Most microorganisms identified were found to be facultat...

  17. BIOCHEMICAL PROCESSES FOR GEOTHERMAL BRINE TREATMENT

    Energy Technology Data Exchange (ETDEWEB)

    PREMUZIC,E.T.; LIN,M.S.; BOHENEK,M.; JOSHI-TOPE,G.; ZHOU,W.; SHELENKOVA,L.; WILKE,R.

    1998-09-20

    As part of the DOE Geothermal Energy Program, BNL's Advanced Biochemical Processes for Geothermal Brines (ABPGB) project is aimed at the development of cost-efficient and environmentally acceptable technologies for the disposal of geothermal wastes. Extensive chemical studies of high and low salinity brines and precipitates have indicated that in addition to trace quantities of regulated substances, e.g., toxic metals such as arsenic and mercury, there are significant concentrations of valuable metals, including gold, silver and platinum. Further chemical and physical studies of the silica product have also shown that the produced silica is a valuable material with commercial potential. A combined biochemical and chemical technology is being developed which (1) solubilizes, separates, and removes environmentally regulated constituents in geothermal precipitates and brines (2) generates an amorphous silica product which may be used as feedstock for the production of revenue generating materials, (3) recover economically valuable trace metals and salts. Geothermal power resources which utilize low salinity brines and use the Stretford process for hydrogen sulfide abatement generate a contaminated sulfur cake. Combined technology converts such sulfur to a commercial grade sulfur, suitable for agricultural use. The R and D activities at BNL are conducted jointly with industrial parties in an effort focused on field applications.

  18. Biochemical processes for geothermal brine treatment

    Energy Technology Data Exchange (ETDEWEB)

    Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Joshi-Tope, G.; Zhou, W.; Shelenkova, L.; Wilke, R.

    1998-08-01

    As part of the DOE Geothermal Energy Program, BNL`s Advanced Biochemical Processes for Geothermal Brines (ABPGB) project is aimed at the development of cost-efficient and environmentally acceptable technologies for the disposal of geothermal wastes. Extensive chemical studies of high and low salinity brines and precipitates have indicated that in addition to trace quantities of regulated substances, e.g., toxic metals such as arsenic and mercury, there are significant concentrations of valuable metals, including gold, silver and platinum. Further chemical and physical studies of the silica product have also shown that the produced silica is a valuable material with commercial potential. A combined biochemical and chemical technology is being developed which (1) solubilizes, separates, and removes environmentally regulated constituents in geothermal precipitates and brines, (2) generates an amorphous silica product which may be used as feedstock for the production of revenue generating materials, (3) recover economically valuable trace metals and salts. Geothermal power resources which utilize low salinity brines and use the Stretford process for hydrogen sulfide abatement generate a contaminated sulfur cake. Combined technology converts such sulfur to a commercial grade sulfur, suitable for agricultural use. The R and D activities at BNL are conducted jointly with industrial parties in an effort focused on field applications.

  19. Serum biochemical markers in carcinoma breast.

    Directory of Open Access Journals (Sweden)

    Seth R

    2003-08-01

    Full Text Available BACKGROUND: Despite the extensive research for many years throughout the world, the etiopathogenesis of cancer still remains obscure. For the early detection of carcinoma of various origins, a number of biochemical markers have been studied to evaluate the malignancy. AIM: To analyse serum gamma glutamyl transpeptidase (GGTP, lactate dehydrogenase (LDH and superoxide dismutase (SOD in carcinoma breast patients. SETTINGS & DESIGN: The serum biochemical markers were estimated in twenty five histopathologically confirmed patients with carcinoma breast and equal number of healthy age- matched individuals served as control. MATERIAL & METHODS: Serum gamma glutamyl transpeptidase (GGTP, lactate dehydrogenase (LDH and superoxide dismutase (SOD were estimated and their sensitivity determined. Statistics: Data was analysed with student′s ′t′-test and sensitivity score of these markers was determined. RESULTS & CONCLUSIONS: The mean serum GGTP, LDH and SOD activities in patients with carcinoma breast were tremendously increased as compared to controls, and a steady increase was observed in their activities from stage I through stage IV as well as following distant metastasis. Serum GGTP, LDH and SOD might prove to be most sensitive biomarkers in carcinoma breast in early detection of the disease.

  20. Biochemical research elucidating metabolic pathways in Pneumocystis*

    Directory of Open Access Journals (Sweden)

    Kaneshiro E.S.

    2010-12-01

    Full Text Available Advances in sequencing the Pneumocystis carinii genome have helped identify potential metabolic pathways operative in the organism. Also, data from characterizing the biochemical and physiological nature of these organisms now allow elucidation of metabolic pathways as well as pose new challenges and questions that require additional experiments. These experiments are being performed despite the difficulty in doing experiments directly on this pathogen that has yet to be subcultured indefinitely and produce mass numbers of cells in vitro. This article reviews biochemical approaches that have provided insights into several Pneumocystis metabolic pathways. It focuses on 1 S-adenosyl-L-methionine (AdoMet; SAM, which is a ubiquitous participant in numerous cellular reactions; 2 sterols: focusing on oxidosqualene cyclase that forms lanosterol in P. carinii; SAM:sterol C-24 methyltransferase that adds methyl groups at the C-24 position of the sterol side chain; and sterol 14α-demethylase that removes a methyl group at the C-14 position of the sterol nucleus; and 3 synthesis of ubiquinone homologs, which play a pivotal role in mitochondrial inner membrane and other cellular membrane electron transport.

  1. Plectasin, a Fungal Defensin, Targets the Bacterial Cell Wall Precursor Lipid II

    DEFF Research Database (Denmark)

    Schneider, Tanja; Kruse, Thomas; Wimmer, Reinhard;

    2010-01-01

    that plectasin, a fungal defensin, acts by directly binding the bacterial cell-wall precursor Lipid II. A wide range of genetic and biochemical approaches identify cell-wall biosynthesis as the pathway targeted by plectasin. In vitro assays for cell-wall synthesis identified Lipid II as the specific cellular...

  2. Biochemical studies on Francisella tularensis RelA in (p)ppGpp biosynthesis

    OpenAIRE

    Wilkinson, Rachael C.; Batten, Laura E.; Wells, Neil J.; Oyston, Petra C. F.; Roach, Peter L.

    2015-01-01

    The bacterial stringent response is induced by nutrient deprivation and is mediated by enzymes of the RSH (RelA/SpoT homologue; RelA, (p)ppGpp synthetase I; SpoT, (p)ppGpp synthetase II) superfamily that control concentrations of the ‘alarmones’ (p)ppGpp (guanosine penta- or tetra-phosphate). This regulatory pathway is present in the vast majority of pathogens and has been proposed as a potential anti-bacterial target. Current understanding of RelA-mediated responses is based on biochemical s...

  3. Stellar Evolution Physics 2 Volume Hardback Set

    Science.gov (United States)

    Iben, Icko

    2012-12-01

    Volume 1: Part I. Introduction and Overview: 1. Qualitative description of single and binary star evolution; 2. Quantitative foundations of stellar evolution theory; Part II. Basic Physical Processes in Stellar Interiors: 3. Properties of and physical processes in the interiors of main sequence stars - order of magnitude estimates; 4. Statistical physics, thermodynamics, and equations of state; 5. Polytropes and single zone models: elementary tools for understanding some aspects of stellar structure and evolution; 6. Hydrogen-burning nuclear reactions and energy-generation rates; 7. Photon-matter interactions and opacity; 8. Equations of stellar evolution and methods of solution; Part III. Pre-Main Sequence, Main Sequence, and Shell Hydrogen Burning Evolution of Single Stars: 9. Star formation and evolution to the main-sequence; 10. Solar structure and neutrino physics; 11. Evolution during core hydrogen-burning phases up to the onset of helium burning; Volume 2: Part IV. Transport Processes, Weak Interaction Processes and Helium-Burning Reactions: 12. Diffusion and gravitational settling; 13. Heat conduction by electrons; 14. Beta decay and electron capture at high densities in stars; 15. The current-current weak interaction and the production of neutrino-antineutrino pairs; 16. Helium-burning nuclear reactions and energy-generation rates; Part V. Evolution during Helium-Burning Phases: 17. Evolution of a low mass model burning helium and hydrogen; 18. Evolution of an intermediate mass model burning helium and hydrogen; 19. Neutron production and neutron capture in a thermally pulsing asymptotic giant branch star of intermediate mass; 20. Evolution of a massive population I model during helium- and carbon-burning stages; Part VI. Terminal Evolution of Low and Intermediate Mass Stars: 21. Wind mass loss on the AGB and formation of a circumstellar envelope, evolution of the remnant as the central star of a planetary nebula, and white dwarf evolution; Index.

  4. Cosmic evolution, life and man

    International Nuclear Information System (INIS)

    Among the most basic problems confronting science are those regarding the origin of the universe, the origin of life and the origin of man. This general overview starts (1) with a brief introduction addressed primarily to the Cyril Ponnamperuma Memorial. Then, the thesis is presented that the appearance of life and intelligence on our planet can be understood as the result of a number of cosmic and biological evolutionary processes, including (2) the stellar thermonuclear synthesis of the biogenic elements other than hydrogen (C, N, O, P and S), their dispersal into space, and their combination into circumstellar and interstellar molecules. (3) The formation of the Solar System and the Earth-Moon System. (4) The role of comets and carbonaceous chondrites in contributing organic matter to the primitive Earth. (5) The prebiotics synthesis of amino acids, purines, pyrimidines, fatty acids, and other biochemical monomers. (6) The prebiotic condensation reactions leading to the synthesis of oligomers such as oligonucleotides and oligopeptides, with replicative and catalytic activities. (7) The synthesis of amphiphilic lipids, and their self-assembly into liposomes with bi-layered membranes. (8) The formation of protocellular structures. (9) The activation of protocells into a functioning Darwin's ancestral cell. (10) Early evolution of life. (11) The K-T boundary event and the disappearance of dinosaurs. (12) Evolution of hominids leading to Homo sapiens. (13) The rapid development of civilization. (14) The exploration of the Solar System. (15) Life beyond our planetary system. (16) Epilogue. Peace from cosmic evolution? (Abstract only)

  5. Evolution and the complexity of bacteriophages

    Directory of Open Access Journals (Sweden)

    Serwer Philip

    2007-03-01

    Full Text Available Abstract Background The genomes of both long-genome (> 200 Kb bacteriophages and long-genome eukaryotic viruses have cellular gene homologs whose selective advantage is not explained. These homologs add genomic and possibly biochemical complexity. Understanding their significance requires a definition of complexity that is more biochemically oriented than past empirically based definitions. Hypothesis Initially, I propose two biochemistry-oriented definitions of complexity: either decreased randomness or increased encoded information that does not serve immediate needs. Then, I make the assumption that these two definitions are equivalent. This assumption and recent data lead to the following four-part hypothesis that explains the presence of cellular gene homologs in long bacteriophage genomes and also provides a pathway for complexity increases in prokaryotic cells: (1 Prokaryotes underwent evolutionary increases in biochemical complexity after the eukaryote/prokaryote splits. (2 Some of the complexity increases occurred via multi-step, weak selection that was both protected from strong selection and accelerated by embedding evolving cellular genes in the genomes of bacteriophages and, presumably, also archaeal viruses (first tier selection. (3 The mechanisms for retaining cellular genes in viral genomes evolved under additional, longer-term selection that was stronger (second tier selection. (4 The second tier selection was based on increased access by prokaryotic cells to improved biochemical systems. This access was achieved when DNA transfer moved to prokaryotic cells both the more evolved genes and their more competitive and complex biochemical systems. Testing the hypothesis I propose testing this hypothesis by controlled evolution in microbial communities to (1 determine the effects of deleting individual cellular gene homologs on the growth and evolution of long genome bacteriophages and hosts, (2 find the environmental conditions that

  6. Functional Consequences of Genome Evolution in Listeria monocytogenes: the lmo0423 and lmo0422 Genes Encode σC and LstR, a Lineage II-Specific Heat Shock System†

    OpenAIRE

    Zhang, Chaomei; Nietfeldt, Joe; Zhang, Min; Benson, Andrew K.

    2005-01-01

    Listeria monocytogenes strains belonging to phylogenetic lineage II (serotypes 1/2a, 1/2c, and 3a) carry a lineage-specific genome segment encoding a putative sigma subunit of RNA polymerase (lmo0423, herein referred to as sigC), a gene of unknown function (lmo0422) similar to the padR family of regulators, and a gene that is similar to the rodA-ftsW family of cell wall morphology genes (lmo0421). To understand the function of this set of genes, their expression patterns and the effects of nu...

  7. Spatial variability of biochemical responses in resident fish after the M/V Hebei Spirit Oil Spill (Taean, Korea)

    Science.gov (United States)

    Jung, Jee-Hyun; Chae, Young Sun; Kim, Ha Na; Kim, Moonkoo; Yim, Un Hyuk; Ha, Sung Yong; Han, Gi Myung; An, Joon Geon; Kim, Eunsic; Shim, Won Joon

    2012-09-01

    This study describes the spatial variation and the duration of the impacts from the Hebei Spirit oil spill using specific biochemical indices in resident benthic fish. Enzymatic activities and biliary PAHs metabolites were higher at the site closer to the spill area in four months after spill incident. Regarding our results of detoxification response, markers of Phase I followed a similar trend in accordance with levels of biliary metabolites, while markers of phase II and GST appeared relatively unchanged.

  8. Evolution of Star Formation in the UKIDSS Ultra Deep Survey Field - II. Star Formation as a Function of Stellar Mass Between z=1.46 and z=0.63

    CERN Document Server

    Drake, Alyssa B; Baldry, Ivan K; James, Phil A; Collins, Chris A; Ouchi, Masami; Yuma, Suraphong; Dunlop, James S; Smith, Daniel J B

    2015-01-01

    We present new results on the evolution of the cosmic star formation rate as a function of stellar mass in the SXDS-UDS field. We make use of narrow-band selected emission line galaxies in four redshift slices between z = 1.46 and z = 0.63, and compute stellar masses by fitting a series of templates to recreate each galaxy's star formation history. We determine mass-binned luminosity functions in each redshift slice, and derive the star formation rate density (rhoSFR) as a function of mass using the [OIII] or [OII] emission lines. We calculate dust extinction and metallicity as a function of stellar mass, and investigate the effect of these corrections on the shape of the overall rhoSFR(M). We find that both these corrections are crucial for determining the shape of the rhoSFR(M), and its evolution with redshift. The fully corrected rhoSFR(M) is a relatively flat distribution, with the normalisation moving towards lower values of rhoSFR with increasing cosmic time/decreasing redshift, and requiring star forma...

  9. The Nature of H$\\beta+$[O{\\sc iii}] and [O{\\sc ii}] emitters to $z \\sim 5$ with HiZELS: stellar mass functions and the evolution of EWs

    CERN Document Server

    Khostovan, Ali Ahmad; Mobasher, Bahram; Smail, Ian; Darvish, Behnam; Nayyeri, Hooshang; Hemmati, Shoubaneh; Stott, John P

    2016-01-01

    We investigate the properties of $\\sim7000$ narrow-band selected galaxies with strong H$\\beta+$[OIII] and [OII] nebular emission lines from the High-$z$ Emission Line Survey (HiZELS) between $z \\sim 0.8 - 5.0$. Our sample covers a wide range in stellar mass ($M\\sim10^{7.5 - 12.0}$ M$_\\odot$), rest-frame equivalent widths (EW$_\\mathrm{rest}\\sim 10 - 10^5$ \\AA), and line luminosities ($L\\sim10^{40.5 - 43.2}$ erg s$^{-1}$). We measure the H$\\beta+$[OIII] and [OII]-selected stellar mass functions out to $z \\sim 3.5$ and find that both $M_\\star$ and $\\phi_\\star$ increases with cosmic time, which may be due to the [OIII] selection including an increasing fraction of AGN at lower redshifts. The [OII]-selected stellar mass functions show a constant $M_\\star\\sim10^{11.6}$ M$_\\odot$ and a strong, increasing evolution with cosmic time in $\\phi_\\star$ in line with H$\\alpha$ studies. We also investigate the EW$_\\mathrm{rest}$ evolution as a function of redshift with a fixed mass range (10$^{9.5 - 10.0}$ M$_\\odot$) and fin...

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

    Science.gov (United States)

    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

  11. Evolution of prokaryote and eukaryote lines inferred from sequence evidence

    Science.gov (United States)

    Hunt, L. T.; George, D. G.; Yeh, L.-S.; Dayhoff, M. O.

    1984-01-01

    This paper describes the evolution of prokaryotes and early eukaryotes, including their symbiotic relationships, as inferred from phylogenetic trees of bacterial ferredoxin, 5S ribosomal RNA, ribulose-1,5-biphosphate carboxylase large chain, and mitochondrial cytochrome oxidase polypeptide II.

  12. Possibilities and methods for biochemical assessment of radiation injury

    International Nuclear Information System (INIS)

    An extensitive review (77 references) is made of the application of biochemical diagnostic methods for assessment of radiation diseases. A brief characteristics of several biochemical indicators is given: deoxycytidine, thymidine, ρ-aminoisocarboxylic acid, DNA-ase, nucleic acids. Influence of such factors as age, sex, season etc. is studied by means of functional biochemical indicators as: creatine, triptophanic metabolites, 5-hydroxy-indolacetic acid, biogenic amines, serum proteins, enzymes, etc

  13. Conceptual Aspects of Theory Appraisal: Some Biochemical Examples

    Directory of Open Access Journals (Sweden)

    F. Michael Akeroyd

    1997-11-01

    Full Text Available This paper considers papers on conceptual analysis by Laudan (1981 and Whitt (1989 and relates them to three biochemical episodes: (1 the modern 'biochemical explanation' of acupuncture; (2 the chemio-osmotic hypothesis of oxidative phosphorylation; (3 the theory of the complete digestion of proteins in the gut. The advantages of including philosophical debate in chemical/biochemical undergraduate courses is then discussed.

  14. Assimilation of ocean colour data into a Biochemical Flux Model of the Eastern Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    G. Triantafyllou

    2006-09-01

    Full Text Available Within the framework of the European MFSTEP project, an advanced multivariate sequential data assimilation system has been implemented to assimilate real chlorophyll data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS into a three-dimensional biochemical model of the Eastern Mediterranean. The physical ocean is described through the Princeton Ocean Model (POM while the biochemistry of the ecosystem is tackled with the Biochemical Flux Model (BFM. The assimilation scheme is based on the Singular Evolutive Extended Kalman (SEEK filter, in which the error statistics were parameterized by means of a suitable set of Empirical Orthogonal Functions (EOFs. A radius of influence was further selected around every data point to limit the range of the EOFs spatial correlations. The assimilation experiment was performed for one year over 1999 and forced with ECMWF 6 hour atmospheric fields. The accuracy of the ecological state identification by the assimilation system is assessed by the relevance of the system in fitting the data, and through the impact of the assimilation on non-observed biochemical processes. Assimilation of SeaWiFS data significantly improves the forecasting capability of the BFM model. Results, however, indicate the necessity of subsurface data to enhance the controllability of the ecosystem model in the deep layers.

  15. Experimental evolution in biofilm populations.

    Science.gov (United States)

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

    2016-05-01

    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.

  16. Experimental evolution in biofilm populations

    Science.gov (United States)

    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

  17. Local biochemical and morphological differences in human Achilles tendinopathy

    DEFF Research Database (Denmark)

    Pingel, Jessica; Fredberg, U.; Qvortrup, Klaus;

    2012-01-01

    The incidence of Achilles tendinopathy is high and underlying etiology as well as biochemical and morphological pathology associated with the disease is largely unknown. The aim of the present study was to describe biochemical and morphological differences in chronic Achilles tendinopathy. The ex....... The expressions of growth factors, inflammatory mediators and tendon morphology were determined in both chronically diseased and healthy tendon parts.......The incidence of Achilles tendinopathy is high and underlying etiology as well as biochemical and morphological pathology associated with the disease is largely unknown. The aim of the present study was to describe biochemical and morphological differences in chronic Achilles tendinopathy...

  18. Hemoglobin variants: biochemical properties and clinical correlates.

    Science.gov (United States)

    Thom, Christopher S; Dickson, Claire F; Gell, David A; Weiss, Mitchell J

    2013-03-01

    Diseases affecting hemoglobin synthesis and function are extremely common worldwide. More than 1000 naturally occurring human hemoglobin variants with single amino acid substitutions throughout the molecule have been discovered, mainly through their clinical and/or laboratory manifestations. These variants alter hemoglobin structure and biochemical properties with physiological effects ranging from insignificant to severe. Studies of these mutations in patients and in the laboratory have produced a wealth of information on hemoglobin biochemistry and biology with significant implications for hematology practice. More generally, landmark studies of hemoglobin performed over the past 60 years have established important paradigms for the disciplines of structural biology, genetics, biochemistry, and medicine. Here we review the major classes of hemoglobin variants, emphasizing general concepts and illustrative examples.

  19. The biochemical basis of hereditary fructose intolerance.

    Science.gov (United States)

    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.

  20. Biochemically enhanced methane production from coal

    Science.gov (United States)

    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

  1. Evaluation of biochemical alterations produced by combined exposure of fenvalerate and nitrate in Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    Kamalpreet Kaur Gill

    2014-03-01

    Full Text Available Aim: Evaluation of combined effect of fenvalerate and nitrate on biochemical parameters in buffalo calves. Materials and Methods: Sixteen male buffalo calves were divided into four groups of four calves each. Group I receiving no treatment served as the control. Group II and III animals were orally administered with fenvalerate (1.0 mg/kg/day and sodium nitrate (20 mg/kg/day, respectively, for 21 consecutive days and were kept as positive control. Group IV animals were co-administered with fenvalerate and sodium nitrate at the above dose rates for 21 consecutive days. Biochemical parameters including Aspartate aminotransferase (AST, Alkaline phosphatase (ALP, Gamma-glutamyl transpeptidase (GGT, Lactate dehydrogenase (LDH, Glucose, Total protein, Albumin, Cholesterol, Blood urea nitrogen (BUN and Creatinine were determined on 0, 3, 7, 10, 14, 17 and 21 day of treatment. Estimation of these parameters was also done on 7th day of post-treatment period. Results: Co-administration of fenvalerate and sodium nitrate produced significant increase in the plasma levels of AST, ALP, GGT, LDH, glucose, BUN, cholesterol and creatinine while significant decrease in the plasma levels of total proteins was observed. No significant alteration was observed in albumin levels. Extent of organ damage as evidenced by biochemical alterations was more pronounced in calves exposed to combination of fenvalerate and sodium nitrate as compared to their individual exposures. Conclusion: Fenvalerate and sodium nitrate co-administration potentiates the toxicological injury produced, in comparison to their individual exposure.

  2. Biochemical and histological alterations in liver following sub chronic exposure of arsenic

    Directory of Open Access Journals (Sweden)

    Madhuri Mehta

    2015-07-01

    Full Text Available Objective: Contamination of groundwater with arsenic is of global concern. The present work was aimed to evaluate the biochemical and histological changes in liver of female rats induced by sodium arsenite at doses naturally found in groundwater of Punjab. Method: Twenty four female rats were divided into four groups of 6 animals each. Group I animals received distilled water and served as control; Group II-IV received arsenic at the dose of 10, 30 and 50 ppb (μg/L dissolved in distilled water ad libitum for 30 days. At the end of experiment, animals were sacrificed and liver was collected for biochemical and histological evaluation. Results: Biochemical analysis showed an increase in the activity of hepatic marker enzymes including transferases, phosphatases and lactate dehydrogenase (LDH. Also, the levels of antioxidant enzymes (catalase, reduced glutathione and glutathione-S-transferase decreased significantly (P<0.05 in treated animals when compared to control. A significant (P<0.05 dose dependent increase in the levels of lipid peroxidation and arsenic concentration in liver tissue was observed. Histological examination showed the presence of pyknotic bodies (necrosis and sinusoidal dilation in hepatocytes of treated groups. Conclusion: Sub chronic exposure of arsenic at these doses induces hepatotoxicity leading to oxidative stress.

  3. Microstructure evolution in the cemented carbides WC-Co II. Cumulated effects of Cr additions and of the C/W ratio on the crystal features of the WC grains

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Lay, S.; Allibert, C.H. [Laboratoire de Thermodynamique et Physico Chimie Metallurgique (UMR CNRS/INPG 5614) BP75, 38402, St-Martin d' Heres (France); Pauty, E. [CERMeP, BP62, 38041 Grenoble Cedex 9 (France)

    2002-09-23

    The influence of an addition of Cr, introduced to replace 5 at% Co on the microstructure evolution of WC-13 at% Co with different C/W ratio is examined at 1450 C. Three alloys consisting of WC and Co binder and containing a graphite or {eta} excess are studied by SEM and TEM. The effects of Cr are similar to those induced by a W excess in the undoped alloys: decrease of the mean grain growth and change of the interface features of the WC grains. The interface modification - less faceted, with steps - indicates a decrease of interface energy anisotropy and suggests a coarsening mechanism limited by the growth of the steps. The specific role of Cr on the hindrance of large grain formation depends on the C/W ratio. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  4. Hubble Space Telescope Hx Imaging of Star-forming Galaxies at z approximately equal to 1-1.5: Evolution in the Size and Luminosity of Giant H II Regions

    Science.gov (United States)

    Livermore, R. C.; Jones, T.; Richard, J.; Bower, R. G.; Ellis, R. S.; Swinbank, A. M.; Rigby, J. R.; Smail, Ian; Arribas, S.; Rodriguez-Zaurin, J.; Colina, L.; Ebeling, H.; Crain, R. A.

    2013-01-01

    We present Hubble Space Telescope/Wide Field Camera 3 narrow-band imaging of the Ha emission in a sample of eight gravitationally lensed galaxies at z = 1-1.5. The magnification caused by the foreground clusters enables us to obtain a median source plane spatial resolution of 360 pc, as well as providing magnifications in flux ranging from approximately 10× to approximately 50×. This enables us to identify resolved star-forming HII regions at this epoch and therefore study their Ha luminosity distributions for comparisons with equivalent samples at z approximately 2 and in the local Universe. We find evolution in the both luminosity and surface brightness of HII regions with redshift. The distribution of clump properties can be quantified with an HII region luminosity function, which can be fit by a power law with an exponential break at some cut-off, and we find that the cut-off evolves with redshift. We therefore conclude that 'clumpy' galaxies are seen at high redshift because of the evolution of the cut-off mass; the galaxies themselves follow similar scaling relations to those at z = 0, but their HII regions are larger and brighter and thus appear as clumps which dominate the morphology of the galaxy. A simple theoretical argument based on gas collapsing on scales of the Jeans mass in a marginally unstable disc shows that the clumpy morphologies of high-z galaxies are driven by the competing effects of higher gas fractions causing perturbations on larger scales, partially compensated by higher epicyclic frequencies which stabilize the disc.

  5. Community Evolution

    CERN Document Server

    Bródka, Piotr; Kazienko, Przemysław

    2016-01-01

    The continuous interest in the social network area contributes to the fast development of this field. The new possibilities of obtaining and storing data facilitate deeper analysis of the entire social network, extracted social groups and single individuals as well. One of the most interesting research topic is the network dynamics and dynamics of social groups in particular, it means analysis of group evolution over time. It is the natural step forward after social community extraction. Having communities extracted, appropriate knowledge and methods for dynamic analysis may be applied in order to identify changes as well as to predict the future of all or some selected groups. Furthermore, knowing the most probably change of a given group some additional steps may be performed in order to change this predicted future according to specific needs. Such ability would be a powerful tool in the hands of human resource managers, personnel recruitment, marketing, telecommunication companies, etc.

  6. Thought Evolution

    Directory of Open Access Journals (Sweden)

    Shadrikov V.D.

    2015-08-01

    Full Text Available The thought evolution is studied by historical reconstruction method that is based on the propositions of the theory of culturalhistorical determination of the psyche development, and the data of the morphological analysis and child development, and the conception of the psyche neuroontogenesis. The grounds for advisability of protothinking are presented. The protothinking is understood as the use of objective thought in cases of awareness absence. It is shown that protothinking is a form of transition from animal thinking to human speech. The particular attention is paid to the process of the word producing and thought generation in that process. The conditions of word producing as cooccurring acoustic pattern served for though expression are discussed. It is emphasized that a word is produced by a particular person. The historical development of the language and the specificity of this development are pointed out

  7. Spinal muscular atrophy type II (intermediary and III (Kugelberg-Welander: evolution of 50 patients with physiotherapy and hydrotherapy in a swimming pool Atrofia muscular espinhal tipo II (intermediária e III (Kugelberg-Welander: evolução de 50 pacientes com fisioterapia e hidroterapia em piscina

    Directory of Open Access Journals (Sweden)

    Márcia C. B. Cunha

    1996-09-01

    Full Text Available We added hydrotherapy to 50 patients with spinal muscular atrophy (SMA who were being treated with individual conventional physiotherapy. Hydrotherapy was performed at an approximate temperature of 30 degrees Celsius, twice a week, for thirty minutes in children and for 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.A hidroterapia foi realizada em SO pacientes com atrofia muscular espinhal, os quais foram também tratados com fisioterapia individual convencional. O tratamento hidroterápico foi realizado em piscina aquecida numa temperatura de aproximadamente 30° Celsius, duas vezes por semana, durante 30 minutos em crianças e 45 minutos em adultos num período de dois anos. Os benefícios deste tipo de tratamento foram avaliados de acordo com a evolução clínica, o MMT(Teste de Força Muscular e a Escala de Barthel. Os pacientes foram reavaliados a cada dois meses. Após dois anos de tratamento nós observamos que as deformidades nos quadris, joelhos e pés foram progressivas em todos os pacientes do Tipo II e em alguns do Tipo III. Houve estabilização da força muscular na maioria dos pacientes com SMA Tipo III, e melhora da força em alguns; nos

  8. Central effects of angiotensin II, its fragment and analogues.

    Science.gov (United States)

    Georgiev, V P; Klousha, V E; Petkov, V D; Markovska, V L; Svirskis, S V; Mountsinietse, R K; Anouans, Z E

    1984-01-01

    The effects of the octapeptide angiotensin II (AT II), its fragment Ile8 AT3-8 and the analogues Sar1 Ala8 AT II, Ala8 AT II and Ile8 AT II were studied with respect to: the level of biogenic amines (DA, 5-HT and their metabolites HVA and 5-HIAA) in the forebrain; the behaviour of the animals--haloperidol catalepsy, apomorphine stereotypy, unconditioned jumping reaction (UJR), convulsive threshold. Good correlation was found between the biochemical and behavioural effects. The fragment of AT II where phenylalanine is substituted at the C-terminal by Ile reduces the haloperidol-increased content of HVA, potentiates apomorphine stereotypy and reduces catalepsy, whereas the AT II analogues (where the C-terminal phenylalanine is substituted by Ala, and the N-terminal--by Sar) potentiate the effect of haloperidol increasing the HVA content, reduce apomorphine stereotypy and potentiate catalepsy; saralasine independently applied induces brief catalepsy; AT II, its fragment and analogues inhibit UJR, in combination with amphetamine and PTZ this effect becomes deeper; the duration of hexobarbital sleep is increased. The peptides investigated increase the convulsive threshold. The results show that the hexapeptide fragment has preserved the effects of AT II, whereas in the analogues (with changed C- and N-terminals) they are changed. The results obtained may be explained with the modulating influence of AT II-receptors on the DA-ergic receptors in the brain structures with which AT II and its fragment and analogues enter in contact.

  9. Om religion og evolution

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2011-01-01

    for kulturens kausale virkning på den menneskelige kognition og ikke mindst den hominine evolution. Ud fra, hvad vi ved om den menneskelige evolution, ses det, at den hominine evolution har en dybde, som sjældent medtænkes i teorier og hypoteser om den menneskelige evolution. Den menneskelige evolution er...

  10. Circuit topology and the evolution of robustness in two-gene circadian oscillators

    OpenAIRE

    Wagner, Andreas

    2005-01-01

    Many parameters driving the behavior of biochemical circuits vary extensively and are thus not fine-tuned. Therefore, the topology of such circuits (the who-interacts-with-whom) is key to understanding their central properties. I here explore several hundred different topologies of a simple biochemical model of circadian oscillations to ask two questions: Do different circuits differ dramatically in their robustness to parameter change? If so, can a process of gradual molecular evolution find...

  11. Model-Based Design of Biochemical Microreactors.

    Science.gov (United States)

    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. Four methods compared for measuring des-carboxy-prothrombin (PIVKA-II).

    Science.gov (United States)

    Widdershoven, J; van Munster, P; De Abreu, R; Bosman, H; van Lith, T; van der Putten-van Meyel, M; Motohara, K; Matsuda, I

    1987-11-01

    PIVKA-II (Protein Induced by Vitamin K Absence) is abnormal des-carboxylated prothrombin, which is present in vitamin K deficiency or in patients using warfarin. With a sensitive method for PIVKA-II, biochemical vitamin K deficiency can be established before clinical symptoms occur. We give an overview of methods used to detect PIVKA-II, and four selected methods are inter-compared: (a) measuring total factor II including PIVKA-II by using Echis carinatus snake venom as an activator of prothrombin; (b) measuring PIVKA-II by using snake venom as an activator of factor II after adsorption of functional factor II onto barium sulfate; (c) electrophoresis-immunofixation method; and (d) enzyme immunoassay. We found d to be the most sensitive and reliable method for PIVKA-II.

  13. Calibration campaign against the international prototype of the kilogram in anticipation of the redefinition of the kilogram, part II: evolution of the BIPM as-maintained mass unit from the 3rd periodic verification to 2014

    Science.gov (United States)

    de Mirandés, Estefanía; Barat, Pauline; Stock, Michael; Milton, Martin J. T.

    2016-10-01

    In 2014 the Bureau International des Poids et Mesures (BIPM) carried out a calibration campaign using the international prototype of the kilogram (IPK). This is the second part in a series of publications describing the results of that campaign. As reported in [Metrologia 52 310–6] following the comparisons between the IPK and its official copies, it was found that the BIPM ‘as-maintained mass unit’ was offset by 35 mg from the mass of the IPK in 2014. We report here the results of an investigation into this offset that has considered all data available from internal BIPM mass comparisons carried out between 1992 and 2014. This has enabled us to model the evolution of the offset in the as-maintained mass unit and to identify some possible reasons why it has developed. We also report how the model has been used to estimate corrections to all 1 kg mass calibration certificates issued by the BIPM during this period.

  14. Phase structure and thermal evolution in coating films and powders obtained by sol-gel process: Part II. ZrO{sub 2}{minus}2.5mole {percent} Y{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, R.; Benavidez, E.; de Sanctis, O. [Laboratorio de Materiales Ceramicos, FCEIyA, IFIR, Av. Pellegrini 250, 2000 Rosario (Argentina); Caracoche, M.C.; Rivas, P.C. [Programa TENAES, Departamento de Fisica, FCE, Universidad Nacional de La Plata, c.c. 67, 1900 La Plata (Argentina); Cervera, M. [Departamento de Ciencia y Tecnologia, Universidad Nacional de Quilmes, R.S. 184, 1864 Bernal (Argentina); Caneiro, A.; Serquis, A. [Centro Atomico Bariloche, CNEA, 8400 Bariloche (Argentina)

    1997-10-01

    Powders and coatings of zirconia doped with 2.5 mole {percent} yttria have been produced via the sol-gel route. The phase structure and subsequent thermal evolution in heating and cooling cycles have been investigated using mainly perturbed angular correlations spectroscopy. Thermal analyses and XRD as a function of temperature have also been performed to obtain complementary information. Upon heating, the amorphous gels crystallized into the tetragonal structure and showed the same hyperfine pattern and thermal behavior as observed in tetragonal zorconia obtained by the ceramic route: the two configurations vacancies around zirconium ions denoted as t{sub 1} and t{sub 2} forms and their mutual t{sub 1}{r_arrow}t{sub 2} transformation. While the powder sample exhibited an incipient thermal instability above 1000{degree}C and underwent completely the t{sub 2} form to m{endash}ZrO{sub 2} transition during subsequent, gradual cooling below 500{degree}C, the coating retained the tetragonal phase within the whole temperature range investigated. Hyperfine results suggest that the tetragonal phase stabilization is favored by the highly defective nature of the t{sub 1} form and consequently hardened by the availability of oxygen. The PAC derived activation energy for the fast diffusion of the oxygen vacancies inherent to the t{sub 2} form was determined as 0.54{plus_minus}0.14eV. {copyright} {ital 1997 Materials Research Society.}

  15. Giant Radio Sources in View of the Dynamical Evolution of FRII-type Population. II. The Evolutionary Tracks on the P-D and u_{c}-E_{tot} Planes

    CERN Document Server

    Machalski, J; Jamrozy, M

    2004-01-01

    The time evolution of `fiducial' radio sources derived from fitting the dynamical model of Kaiser et al. (1997) is compared with the observational data for the `clan' sources found in the sample of giant and normal-size FRII-type sources published Paper I (Machalski et al. 2004). Each `clan' comprises 3, 4 or 5 sample sources having similar values of the two basic physical parameters: the jet power Q_{0} and central density of the galaxy nucleus rho_{0} (determined in Paper I) but different ages, radio luminosities and axial ratios. These sources are considered as the `same' source observed at different epochs of its lifetime and used to fit the evolutionary luminosity-size (P-D) and energy density-total energy (u_{c}-E_{tot}) tracks derived from the model for a `fiducial' source with Q0 and rho_{0} equal to the means of relevant values obtained for the `clan' members, as well as to constrain the evolutionary model of the source dynamics used. In the result we find that (i) The best fit is achieved when the K...

  16. The Metal Abundance across Cosmic Time ($\\mathcal{MACT}$) Survey II: Evolution of the Mass-Metallicity Relation over 8 Billion Years, using [OIII]$\\lambda$4363\\AA-based Metallicities

    CERN Document Server

    Ly, Chun; Rigby, Jane; Nagao, Tohru

    2016-01-01

    [Abridged] We present the results of MMT and Keck spectroscopy for a large sample of $0.1\\leq z\\leq1$ emission-line galaxies selected from our narrow-band imaging in the Subaru Deep Field. In total, we have measured the weak [OIII]$\\lambda$4363 line for 164 galaxies (66 with at least 3$\\sigma$ detections, and 98 with significant upper limits). The strength of this nebular emission line is set by the electron temperature ($T_e$) for the ionized gas in these galaxies. Since the gas temperature is regulated by the metal content, an inverse relationship exists between gas-phase oxygen abundance and [OIII]$\\lambda$4363 line strength. Our $T_e$-based metallicity study is the first to span $\\approx$8 Gyr of cosmic time and $\\approx$3 dex in stellar mass for low-mass galaxies, $\\log{(M_{star}/M_{sun})}\\approx6.0-9.0$. Combined with extensive multi-wavelength photometry, we investigate the evolution of the stellar mass--gas metallicity relation, and its dependence on dust-corrected star formation rate. The latter is o...

  17. Definitions of biochemical failure in prostate cancer following radiation therapy

    International Nuclear Information System (INIS)

    Purpose: The American Society for Therapeutic Radiology and Oncology (ASTRO) published a consensus panel definition of biochemical failure following radiation therapy for prostate cancer. In this paper, we develop a series of alternative definitions of biochemical failure. Using data from 688 patients, we evaluated the sensitivity and specificity of the various definitions, with respect to a defined 'clinically meaningful' outcome. Methods and Materials: The ASTRO definition of biochemical failure requires 3 consecutive rises in prostate-specific antigen (PSA). We considered several modifications to the standard definition: to require PSA rises of a certain magnitude, to consider 2 instead of 3 rises, to require the final PSA value to be greater than a fixed cutoff level, and to define biochemical failure based on the slope of PSA over 1, 1.5, or 2 years. A clinically meaningful failure is defined as local recurrence, distant metastases, initiation of unplanned hormonal therapy, unplanned radical prostatectomy, or a PSA>25 later than 6 months after radiation. Results: Requiring the final PSA in a series of consecutive rises to be larger than 1.5 ng/mL increased the specificity of biochemical failure. For a fixed specificity, defining biochemical failure based on 2 consecutive rises, or the slope over the last year, could increase the sensitivity by up to approximately 20%, compared to the ASTRO definition. Using a rule based on the slope over the previous year or 2 rises leads to a slightly earlier detection of biochemical failure than does the ASTRO definition. Even with the best rule, only approximately 20% of true failures are biochemically detected more than 1 year before the clinically meaningful event time. Conclusion: There is potential for improvement in the ASTRO consensus definition of biochemical failure. Further research is needed, in studies with long follow-up times, to evaluate the relationship between various definitions of biochemical failure and

  18. Groupware requirements evolution patterns

    NARCIS (Netherlands)

    Pumareja, Dulce Trinidad

    2013-01-01

    Requirements evolution is a generally known problem in software development. Requirements are known to change all throughout a system's lifecycle. Nevertheless, requirements evolution is a poorly understood phenomenon. Most studies on requirements evolution focus on changes to written specifications

  19. PHA bioplastics, biochemicals, and energy from crops.

    Science.gov (United States)

    Somleva, Maria N; Peoples, Oliver P; Snell, Kristi D

    2013-02-01

    Large scale production of polyhydroxyalkanoates (PHAs) in plants can provide a sustainable supply of bioplastics, biochemicals, and energy from sunlight and atmospheric CO(2). PHAs are a class of polymers with various chain lengths that are naturally produced by some microorganisms as storage materials. The properties of these polyesters make them functionally equivalent to many of the petroleum-based plastics that are currently in the market place. However, unlike most petroleum-derived plastics, PHAs can be produced from renewable feedstocks and easily degrade in most biologically active environments. This review highlights research efforts over the last 20 years to engineer the production of PHAs in plants with a focus on polyhydroxybutryrate (PHB) production in bioenergy crops with C(4) photosynthesis. PHB has the potential to be a high volume commercial product with uses not only in the plastics and materials markets, but also in renewable chemicals and feed. The major challenges of improving product yield and plant fitness in high biomass yielding C(4) crops are discussed in detail. PMID:23294864

  20. Skin biochemical composition analysis by Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Patricia Karen; Tosato, Maira Gaspar; Alves, Rani de Souza; Martin, Airton Abrahao; Favero, Priscila Pereira; Raniero, Leandro, E-mail: amartin@univap.br [Laboratorio de Espectroscopia Vibracional Biomedica, Instituto de Pesquisa e Desenvolvimento - IP e D, Universidade do Vale do Paraiba - UniVap, Sao Jose dos Campos, SP (Brazil)

    2012-09-15

    Skin aging is characterized by cellular and molecular alterations. In this context, Confocal Raman spectroscopy was used in vivo to measure these biochemical changes as function of the skin depth. In this study we have tried to correlate spectra from pure amino acids to in vivo spectra from volunteers with different ages. This study was performed on 32 volunteers: 11 from Group A (20-23 years), 11 from Group B (39-42 years) and 10 from Group C (59-62 years). For each group, the Raman spectra were measured on the surface (0 mm), 30 +- 3 mm and 60 +- 3 {mu}m below the surface. The results from intergroup comparisons showed that the oldest group had a prevalence of the tyrosine band, but it also presented a decrease in the band centered at 875 cm{sup -1} of pyrrolidone acid. The amide I band centered at 1637 cm{sup -1} that is attributed to collagen, as well as other proteins and lipid, showed a smaller amount of these biomolecules for Group C, which can be explained by the decrease in collagen concentration as a function of age. (author)

  1. Biochemical and Proteomic Characterization of Alkaptonuric Chondrocytes

    Science.gov (United States)

    Braconi, Daniela; Bernardini, Giulia; Bianchini, Claretta; Laschi, Marcella; Millucci, Lia; Amato, Loredana; Tinti, Laura; Serchi, Tommaso; Chellini, Federico; Spreafico, Adriano; Santucci, Annalisa

    2012-01-01

    Alkaptonuria (AKU) is a rare genetic disease associated with the accumulation of homogentisic acid (HGA) and its oxidized/polymerized products which leads to the deposition of melanin-like pigments (ochronosis) in connective tissues. Although numerous case reports have described ochronosis in joints, little is known on the molecular mechanisms leading to such a phenomenon. For this reason, we characterized biochemically chondrocytes isolated from the ochronotic cartilage of AKU patients. Based on the macroscopic appearance of the ochronotic cartilage, two sub-populations were identified: cells coming from the black portion of the cartilage were referred to as “black” AKU chondrocytes, while those coming from the white portion were referred to as “white” AKU chondrocytes. Notably, both AKU chondrocytic types were characterized by increased apoptosis, NO release, and levels of pro-inflammatory cytokines. Transmission electron microscopy also revealed that intracellular ochronotic pigment deposition was common to both “white” and “black” AKU cells. We then undertook a proteomic and redox-proteomic analysis of AKU chondrocytes which revealed profound alterations in the levels of proteins involved in cell defence, protein folding, and cell organization. An increased post-translational oxidation of proteins, which also involved high molecular weight protein aggregates, was found to be particularly relevant in “black” AKU chondrocytes. J. Cell. Physiol. 227: 3333–3343, 2012. © 2011 Wiley Periodicals, Inc. PMID:22213341

  2. NUTRITION AND SPORTS: A BIOCHEMICAL APPROACH

    Directory of Open Access Journals (Sweden)

    A.A.G. Bianco

    2004-05-01

    Full Text Available This work presents a course dedicated to the pedagogical instruction of graduate students (Ensino deBioqumica - QBQ 5711 in which they have to plan and teach a 30 hour-discipline for undergraduatestudents. The graduate students have to choose a subject for the discipline and, in 2003, the cho-sen subject was Nutrition and Sports: a Biochemical Approach, which is not specically broached inregular disciplines. The discipline was structured in the basis of collaborative learning, thus, the 75 en-rolled undergraduate students (from dierent courses as Nutrition, Sports, Pharmacy, Chemistry andBiology were organized in small working groups. The students were given a study guide produced bythe graduate teachers (available in Portuguese at http://www.sbbq.org.br/revista/mtdidaticos.php,in which the following contents were covered: muscle contraction, O2 up-take, oxidative stress andanti-oxidant response, cramp, hydration, doping and nutritional supplies. In the nal activity thestudents had to evaluate critically myths and true facts in 80 statements usually associated to physi-cal activities and sports. The discipline was evaluated through questionnaires. From the analysis ofthe answers of both undergraduate and graduate/teachers students it is possible to conclude that thediscipline was well conduced and succeeded. These results emphasize the relevance and contribution ofthis kind of discipline to the pedagogical instruction of the graduate students and also to the increaseof undergraduate students interests in Biochemistry.

  3. BALL - biochemical algorithms library 1.3

    Directory of Open Access Journals (Sweden)

    Stöckel Daniel

    2010-10-01

    Full Text Available Abstract Background The Biochemical Algorithms Library (BALL is a comprehensive rapid application development framework for structural bioinformatics. It provides an extensive C++ class library of data structures and algorithms for molecular modeling and structural bioinformatics. Using BALL as a programming toolbox does not only allow to greatly reduce application development times but also helps in ensuring stability and correctness by avoiding the error-prone reimplementation of complex algorithms and replacing them with calls into the library that has been well-tested by a large number of developers. In the ten years since its original publication, BALL has seen a substantial increase in functionality and numerous other improvements. Results Here, we discuss BALL's current functionality and highlight the key additions and improvements: support for additional file formats, molecular edit-functionality, new molecular mechanics force fields, novel energy minimization techniques, docking algorithms, and support for cheminformatics. Conclusions BALL is available for all major operating systems, including Linux, Windows, and MacOS X. It is available free of charge under the Lesser GNU Public License (LPGL. Parts of the code are distributed under the GNU Public License (GPL. BALL is available as source code and binary packages from the project web site at http://www.ball-project.org. Recently, it has been accepted into the debian project; integration into further distributions is currently pursued.

  4. PHA bioplastics, biochemicals, and energy from crops.

    Science.gov (United States)

    Somleva, Maria N; Peoples, Oliver P; Snell, Kristi D

    2013-02-01

    Large scale production of polyhydroxyalkanoates (PHAs) in plants can provide a sustainable supply of bioplastics, biochemicals, and energy from sunlight and atmospheric CO(2). PHAs are a class of polymers with various chain lengths that are naturally produced by some microorganisms as storage materials. The properties of these polyesters make them functionally equivalent to many of the petroleum-based plastics that are currently in the market place. However, unlike most petroleum-derived plastics, PHAs can be produced from renewable feedstocks and easily degrade in most biologically active environments. This review highlights research efforts over the last 20 years to engineer the production of PHAs in plants with a focus on polyhydroxybutryrate (PHB) production in bioenergy crops with C(4) photosynthesis. PHB has the potential to be a high volume commercial product with uses not only in the plastics and materials markets, but also in renewable chemicals and feed. The major challenges of improving product yield and plant fitness in high biomass yielding C(4) crops are discussed in detail.

  5. Morphological and Biochemical Diversity of Dalmatian Pyrethrum (Tanacetum cinerariifolium (Trevir. Sch. Bip.

    Directory of Open Access Journals (Sweden)

    Martina Grdiša

    2009-06-01

    Full Text Available Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip. is a perennial herbaceous plant belonging to the Asteraceae family. It is endemic to the East coast of the Adriatic Sea and its natural habitat extends from Italy to northern Albania and up in the mountainous regions of Croatia, Bosnia and Herzegovina and Montenegro. Pyrethrum flowers yield an important insecticide, the pyrethrin. Pyrethrin is mainly concentrated in oil glands on the surface of the seed inside the tightly packed flower head, but they can also be found in the other plant parts, however in much lower concentrations. The pyrethrin exist as a combination of six insecticide active ingredients: pyrethrin I, cinerin I, jasmolin I, pyrethrin II, cinerin II and jasmolin II, with pyrethrin I and pyrethrin II present in higher concentrations. Pyrethrin is non-toxic to mammals and other worm-blooded animals, it is unstable in light, oxygen, water and at elevated temperatures and therefore highly biodegradable. Due to the fact it is environmentally safe it is leading insecticide in organic farming systems. The most scientific work concerning Dalmatian pyrethrum was focused on its morphological and biochemical traits that are relevant in breeding. Breeding programmes are primarily focused on increasing the yield of pyrethrin per unit area. Relative to dry flower weight, flower heads contain the majority of the pyrethrin. Croatian wild populations contain approximately 0.60 to 0.79 %, while clones in breeding programmes of Australia and Kenya contain up to 3.0 % of pyrethrin.

  6. Predicting outcomes in organophosphate poisoning based on APACHE II and modified APACHE II scores.

    Science.gov (United States)

    Eizadi-Mood, N; Saghaei, M; Jabalameli, M

    2007-07-01

    The aim of this study was to evaluate the scores of the Acute Physiology and Chronic Health Evaluation (APACHE) II and a modified APACHE II system (MAS), without parameters of biochemical tests; and to find prognostic value of individual elements of the APACHE II and MAS in predicting outcomes in organophosphate (OP) poisoning. Data were collected from 131 patients. The median (25th-75th percentiles) of APACHE II score for survivors without intubation were found to be lower than those of non survivors or survivors with intubation and ventilation, [4 (1-7); versus 17.5 (7.8-29), and 13.5 (7.8-16.3)]. Logistic regression analysis identified white blood cell (WBC), potassium, Glasgow coma scale (GCS), age and sodium in APACHE II; GCS and mean arterial pressure in MAS system as prognostically valuable. There was no statistically significance difference between APACHE II and MAS scores in terms of area under Receiver Operating Characteristic Curve [(0.902, 95% confidence interval: (0.837-0.947) for APACHE II), and (0.892, 95% confidence interval: (0.826-0.940) for MAS); P=0.74) to predict need for intubation. It is concluded usage of MAS facilitates the prognostication of the OP poisoned patients due to simplicity, less time-consuming and effectiveness in an emergency situation.

  7. Has Human Evolution Stopped?

    OpenAIRE

    Templeton, Alan R.

    2010-01-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important ...

  8. [Tyrosinemia type II. Case report].

    Science.gov (United States)

    Benatiya, A I; Bouayed, M A; Touiza, E; Daoudi, K; Bhalil, S; Elmesbahi, I; Tahri, H

    2005-01-01

    Tyrosinemia type II or Richner-Hanhart syndrome is a rare hereditary disease characterized by the association of pseudoherpetiform corneal ulcerations and palmoplantar hyperkeratosis. We report the case of a 12 year-old young man presenting a superficial punctate keratitis and a corneal dystrophy in both eyes, associated with a palmoplantar hyperkeratosis. The dosage of the serum level of tyrosine is meaningfully raised to 1236 micromol/l. A dietary treatment restraining tyrosine and phenylalanine is started with favorable results after an evolution of 6 months. Tyrosinemia type II is an autosomal recessive disease, due to an enzymatic deficit in tyrosine aminotransferase. The diagnosis is based on the clinic and high level of serum and urinary tyrosine as well as of its urinary metabolites. This disease must be suspected in all cases of dentritic keratitis not reacting on the antiviral treatment, and more especially if it is associated with cutaneous lesions such as palmo-plantar keratosis.

  9. Elizabeth II uus kunstigalerii

    Index Scriptorium Estoniae

    1999-01-01

    Tähistamaks oma troonile asumise 50. aastapäeva, avab Elizabeth II 6. II 2002 Buckinghami palees uue kunstigalerii, mis ehitatakse palee tiibhoonena. Arhitekt John Simpson. Elizabeth II kunstikogust

  10. Guess-Work and Reasonings on Centennial Evolution of Surface Air Temperature in Russia. Part II: Is it Possible to Research Both Local Peculiarities and Regional Tendencies from the Bifurcation Analysis Viewpoint?

    Science.gov (United States)

    Kolokolov, Yury; Monovskaya, Anna

    analyze. Since only the historical data of the temperature observations are used, then the results approach as close as possible to the real events. We believe that our research seems to be interesting to estimate the theoretically possible latent abilities and evolution of the local climate dynamics.

  11. Diclofenac-induced biochemical and histopathological changes in white leghorn birds (Gallus domesticus

    Directory of Open Access Journals (Sweden)

    Jain Teenu

    2009-01-01

    Full Text Available Objective : Objective: To evaluate diclofenac-induced biochemical and histopathological changes in White Leghorn birds. Materials and Methods : Six-week-old birds were equally divided into three groups of six birds each. Group I served as control and received vehicle orally. The birds of Group II and III were orally administered with a single low (2 mg/kg and high dose (20 mg/kg of diclofenac sodium, respectively, and were observed for 7 days. The acute toxicity was assessed by observing the clinical signs and symptoms, mortality, alterations in blood biochemistry, and necropsy findings. Results : The birds of Group II showed only mild symptoms of diarrhea. In Group III, 50% of birds died in between 24 and 36 h post-treatment showing the symptoms of segregatory behavior, lethargy, terminal anorexia, and severe bloody diarrhea. The birds of Group II and the surviving birds of Group III showed a significantly (P< 0.05 increased plasma uric acid, creatinine and plasma glutamic pyruvic transaminase (PGPT, and decreased total protein and albumin at 12 and 24 h post-treatment which returned to the normal levels at 36 h post-treatment. The dead birds of the high-dose group also showed similar pattern of biochemical changes at 12 and 24 h post-treatment and revealed extensive visceral gout with characteristic histopathological lesions in liver, kidney, heart, spleen, and intestine on post-mortem. Conclusion : The results indicate that diclofenac sodium has hepatotoxic, nephrotoxic, and visceral gout inducing potentials in White Leghorn birds, especially at higher dose.

  12. Membrane interactions in nerve myelin: II. Determination of surface charge from biochemical data.

    OpenAIRE

    Inouye, H.; Kirschner, D A

    1988-01-01

    In our accompanying paper (Inouye and Kirschner, 1988) we calculated the surface charge density at the extracellular surfaces in peripheral and central nervous system (PNS; CNS) myelins from observations on the dependency of the width of the extracellular space on pH and ionic strength. Here, we have determined the surface charge density of the membrane surfaces in myelin from its chemical composition and the localization of some of its molecular components. We then analyzed the attractive an...

  13. Biochemical studies on the conversion of tumor cells to their counterpart normal cells(II)

    International Nuclear Information System (INIS)

    We describe here the expression of c-fos oncogene in the growth stimulated cells e.g., mouse prenatal tissues, FCS treated NIH-3T3 fibroblast and A549 human lung cancer cells. Total cellular RNA was isolated from A/J and C57BL/5J mouse embryos at the 13 and 17 day of pregnancy. NIH-3T3 mouse fibroblast and A549 lung cancer cells were stimulated using the 15% FCS after serum depletion for 2-3 days. During the serum stimulation, c-fos expression was detected at time intervals by the dot blot analysis using the 32 P-labelled c-fos DNA probe. RNAs isolated from mouse prenatal tissues were strongly hybridized with c-fos. c-fos induction was detected from 30 minutes after serum stimulation in NIH-3T3 cells, and turned off after 2hrs. On the other hand, c-fos in the A549 lung cancer cells was independent on the serum stimulation and very strongly expressed even in the serum depleted codition. These results indicate the possible implication of growth control by the turning off the oncogene expression. (Author)

  14. EVALUATION OF THE EXTRACTS OF LEUCAS ASPERA ON BIOCHEMICAL PROFILES IN EXPERIMENTAL MODEL OF DIABETES MELLITUS (TYPE- I IN RATS

    Directory of Open Access Journals (Sweden)

    T.Tukaram

    2011-03-01

    Full Text Available The study was conducted to evaluate the effect of Leucas aspera leaves on experimental diabetes mellitus (type I in rats in terms of alterations in biochemical profiles. Thirty rats were randomly divided into six groups of 5 rats in each. Group-I were fed on basal diet without any treatment, group-II induced diabetic models (type-I (Alloxan monohydrate dissolved in sterile normal saline (150 mg/kgBW, ip, group-III, IV, V and VI were induced diabetics and treated with extract of Leucas aspera (30,100,150 and 300mg/kg BW respectively, PO twice daily in the morning and evening post prandially for thirty days respectively. The blood samples were collected on day 0, 10, 20 and 30 and were used for the analysis of biochemical profiles.The blood glucose (mg% were consistently increased significantly (P<0.01 in groups II,III, IV V and VI till day 20 while in groups V and VI there was a significant (P<0.01 decline in the values on day 30. There was found to have profound effect in lowering the blood glucose levels in dose dependent manner. The study revealed that experimental diabetes mellitus (type-I induced patho-biochemical changes were ameliorated more effectively by ethanolic extract of Leucas aspera in dose dependent manner.

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

    Science.gov (United States)

    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...

  16. Evolution of Soil Biochemical Parameters in Rainfed Crops: Effect of Organic and Mineral Fertilization

    OpenAIRE

    Marta M. Moreno; Carmen Moreno; Carlos Lacasta; Ramón Meco

    2012-01-01

    In organic farming, crop fertilization is largely based on the decomposition of organic matter and biological fixation of nutrients. It is therefore necessary to develop studies conducted to know and understand the soil biological processes for the natural nutrient supplies. The effect of three fertilizer managements (chemical with synthetic fertilizers, organic with 2500 kg compost ha−1, and no fertilizer) in a rainfed crop rotation (durum wheat-fallow-barley-vetch as green manure) on differ...

  17. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy.

    Directory of Open Access Journals (Sweden)

    Omar Julián Hernández Ojeda

    2011-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Fundamento: la hepatitis C es uno de los principales problemas de salud a nivel mundial y la indicación más frecuente de transplante hepático en muchos países. Objetivo: determinar la evolución bioquímica y respuesta histológica de pacientes con hepatitis crónica tipo C bajo tratamiento con Interferón alfa 2b recombinante y ribavirina atendidos en consulta provincial de Hepatología. Métodos: estudio observacional y descriptivo, en 31 pacientes portadores del virus de la hepatitis C, remitidos a la consulta de Hepatología Provincial de Cienfuegos en el Hospital Universitario “Dr. Gustavo Aldereguía Lima”, entre enero de 2007 y junio de 2009; y tratados con interferon alfa 2b recombinante más ribavirina. Se estudiaron las variables: edad, sexo, posible vía de infección, valores séricos de alanito aminotransferasa, evaluación bioquímica (al concluir el tratamiento y al finalizar el seguimiento y respuesta histológica. Para la evaluación de la actividad histológica de las lesiones hepáticas crónicas se empleó el índice de Knodell. Para comparar los resultados (respuesta bioquímica y la respuesta histológica antes y después del tratamiento se empleó la Prueba de los Signos. Resultados: El sexo femenino predominó en la muestra (58,1 %. La edad promedio fue de 45,5±11,6 años. La vía posible de trasmisión no se pudo identificar en 51,6 % de los pacientes. El tratamiento quirúrgico fue identificado como vía de infección en el 22,6 %, seguido del tratamiento parenteral reiterado (16,1 %. Conclusión: al finalizar el tratamiento se obtuvo un mayor porcentaje de respuesta en cuanto a la evolución bioquímica y a la respuesta histológica.

  18. SOME BIOCHEMICAL BLOOD CONSTANTS EVOLUTION IN REPORT TO THE TRAINING SCHEDULE STAGE IN SPORT HORSES

    Directory of Open Access Journals (Sweden)

    FLAVIA BOCHIS

    2013-12-01

    Full Text Available To determine whether a clinical examination was adequate to assess the fitness of horses in a fence course riding, and to characterize the relationship between a clinical assessment of the horse's fitness, training schedule stage and its blood biochemistry, 22 horses were monitored before (S1, during training, immediately after warming-up (S2 and after an E level fence obstacle course ride (S3. The blood samples were taken from the jugular vein in the above three mentioned phases, for the determination of total protein (g/dl, nitrogen (mg/dl, glucose (mg/dl, lactic acid (nmol/l, calcium (mg/dl, cholesterol (mg/dl and phosphorus (mg/dl. The intend of the paper is to present the obtained results as a reference study for the appropriate use by clinicians, sport horses owners and trainers in view to have a solid base in evaluation, for the adequate protection of health and welfare of the jumper horses competitors.

  19. Evolution of biochemical parameters in irradiated fishes: Serum proteins and intestinal nucleic acids

    International Nuclear Information System (INIS)

    In sublethal gamma-irradiated C. auratus, a sudden decrease of total serum protein concentration and a preferential descent of the low molecular weight gamma-globulin fraction have been observed. These effects are transient and after different latent periods dependent on doses, normal values are recovered, A temporal failure of a vascular permeability regulation system is probably implied. The DMA depolymerization. observed in the intestine indicates the action of radio-induced DNA degradation mechanisms since this effect is independent on doses. (Author) 29 refs

  20. RESEARCES REGARDING THE SANGUINE CORTISOL EVOLUTION, AS BIOCHEMICAL INDEX, IN SPORT HORSES IN COMPLETE HORSE TRIAL

    Directory of Open Access Journals (Sweden)

    EUGENIA ŞOVĂREL

    2013-12-01

    Full Text Available Using the horse for sport activities needs a good training and an optimization ofphysical and psychical qualities, both contributing to achieve the wantedperformances. Physical effort impose to the horse in different competitions is a stresssituation, fact which induce an endocrine answer, materialised through increasingthe sanguine levels of some hormones and decreasing of others. The purpose of thisstudy was to verify if the training and the effort intensity is reflected in the sanguinecortisol behaviour in sport horses.

  1. Biochemical Evolution and Histological Response of Patients with Hepatitis C Undergoing Antiviral Therapy.

    OpenAIRE

    Omar Julián Hernández Ojeda; Marcos Félix Osorio Pagola; Orelvis Martínez Martínez; Denis Monzón Vega; Mabel Vega Galindo

    2011-01-01

    Fundamento: la hepatitis C es uno de los principales problemas de salud a nivel mundial y la indicación más frecuente de transplante hepático en muchos países. Objetivo: determinar la evolución bioquímica y respuesta histológica de pacientes con hepatitis crónica tipo C bajo tratamiento con Interferón alfa 2b recombinante y ribavirina atendidos en consulta provincial de Hepatología. Métodos: estudio observacional y descriptivo, en 31 pacientes portadores del virus de la hepatitis C, remit...

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

    OpenAIRE

    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 spec...

  3. Role of cryptic genes in microbial evolution.

    Science.gov (United States)

    Hall, B G; Yokoyama, S; Calhoun, D H

    1983-12-01

    Cryptic genes are phenotypically silent DNA sequences, not normally expressed during the life cycle of an individual. They may, however, be activated in a few individuals of a large population by mutation, recombination, insertion elements, or other genetic mechanisms. A consideration of the microbial literature concerning biochemical evolution, physiology, and taxonomy provides the basis for a hypothesis of microbial adaptation and evolution by mutational activation of cryptic genes. Evidence is presented, and a mathematical model is derived, indicating that powerful and biologically important mechanisms exist to prevent the loss of cryptic genes. We propose that cryptic genes persist as a vital element of the genetic repertoire, ready for recall by mutational activation in future generations. Cryptic genes provide a versatile endogenous genetic reservoir that enhances the adaptive potential of a species by a mechanism that is independent of genetic exchange.

  4. Biochemical and biotechnological approaches as basis for structure determination of pigment-protein complexes of oxygenic photosynthesis

    OpenAIRE

    Fey, Holger

    2009-01-01

    Today the structure of photosystem II, which is the enzyme responsible for the evolution of molecular oxygen by plants, algae and cyanobacteria, is known up to a resolution of about 3.0 Å in cyanobacteria (Loll et al., 2005). Photosystem II of higher plants, which shows some differences compared to the photosystem II of cyanobacteria, is not resolved in such high detail, yet (8-10 Å) (Rhee et al., 1998; Hankamer et al., 2001a). Therefore, the molecular structure of PSII of higher plants and i...

  5. Origins and Evolution of Life

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  7. Group II Intron Self-Splicing.

    Science.gov (United States)

    Pyle, Anna Marie

    2016-07-01

    Group II introns are large, autocatalytic ribozymes that catalyze RNA splicing and retrotransposition. Splicing by group II introns plays a major role in the metabolism of plants, fungi, and yeast and contributes to genetic variation in many bacteria. Group II introns have played a major role in genome evolution, as they are likely progenitors of spliceosomal introns, retroelements, and other machinery that controls genetic variation and stability. The structure and catalytic mechanism of group II introns have recently been elucidated through a combination of genetics, chemical biology, solution biochemistry, and crystallography. These studies reveal a dynamic machine that cycles progressively through multiple conformations as it stimulates the various stages of splicing. A central active site, containing a reactive metal ion cluster, catalyzes both steps of self-splicing. These studies provide insights into RNA structure, folding, and catalysis, as they raise new questions about the behavior of RNA machines. PMID:27391926

  8. The diversity challenge in directed protein evolution.

    Science.gov (United States)

    Wong, Tuck Seng; Zhurina, Daria; Schwaneberg, Ulrich

    2006-05-01

    Over the past decade, we have witnessed a bloom in the field of evolutive protein engineering which is fueled by advances in molecular biology techniques and high-throughput screening technology. Directed protein evolution is a powerful algorithm using iterative cycles of random mutagenesis and screening for tailoring protein properties to our needs in industrial applications and for elucidating proteins' structure function relationships. This review summarizes, categorizes and discusses advantages and disadvantages of random mutagenesis methods used for generating genetic diversity. These random mutagenesis methods have been classified into four main categories depending on the method employed for nucleotide substitutions: enzyme based methods (Category I), synthetic chemistry based methods (Category II), whole cell methods (Category III) and combined methods (Category I-II, I-III and II-III). The basic principle of each method is discussed and varied mutagenic conditions are summarized in Tables and compared (benchmarked) to each other in terms of: mutational bias, controllable mutation frequency, ability to generate consecutive nucleotide substitutions and subset diversity, dependency on gene length, technical simplicity/robustness and cost-effectiveness. The latter comparison shows how highly-biased and limited current diversity creating methods are. Based on these limitations, strategies for generating diverse mutant libraries are proposed and discussed (RaMuS-Flowchart; KISS principle). We hope that this review provides, especially for researchers just entering the field of directed evolution, a guide for developing successful directed evolution strategies by selecting complementary methods for generating diverse mutant libraries.

  9. biochemical and hormonal studies in obese cases

    International Nuclear Information System (INIS)

    The present study was carried out on a total number of 116 obese and 23 non-obese control females. Obesity was assessed mainly by body mass index (BMI). Other skinfold thickness e.g. triceps, subscapular, suprailiac, as parameters of obesity assessment were determined in some obese patients. The degree of obesity was assessed by BMI and categorized as follows: i- Mild obesity, BMI=25-30 Kg/m2. ii-Moderate obesity, BMI=31-35 kg/m2. iii-severe obesity, BMI= above 35 kg/m2. Type of fat distribution was assessed by waist/hip circumference ratio (w/H) as :- i-gynoid (lower body segment obesity). (≤ 0.81) i i- android (upper body segment obesity). (≥0.82)

  10. 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.

    Science.gov (United States)

    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. PMID:27163673

  11. Biochemical Aspects of Acclimatization of Man to High Altitude Stress

    Directory of Open Access Journals (Sweden)

    K. K. Srivastava

    1975-07-01

    Full Text Available The paper reviews the biochemical aspects of acclimatization of human body to high altitude with particular reference to the adaptive changes in Skeletal muscles, hepatic function, adrenal function and carbohydrate metabolism.

  12. Biochemical methane potential (BMP) of solid organic materials

    DEFF Research Database (Denmark)

    Raposo, Francisco; Fernández-Cegrí, V.; De la Rubia, M.A.;

    2010-01-01

    This paper describes the results obtained for different participating research groups in an interlaboratory study related to the biochemical methane potential (BMP). In this research work, the full experimental conditions influencing the test such as inoculum, substrate characteristics and experi...

  13. 2011 Biomass Program Platform Peer Review: Biochemical Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Pezzullo, Leslie [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    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.

  14. Assessment of biochemical concentrations of vegetation using remote sensing technology

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The main biochemicals (such as lignin, protein, cellulose, sugar, starch, chlorophyll and water) of vegetation are directly or indirectly involved in major ecological processes, such as the functions of terrestrial ecosystems (i.e., nutrient-cycling processes, primary production, and decomposition). Remote sensing techniques provide a very convenient way of data acquisition capable of covering a large area several times during one season, so it can play a unique and essential role provided that we can relate remote sensing measurements to the biochemical characteristics of the Earth surface in a reliable and operational way. The application of remote sensing techniques for the estimation of canopy biochemicals was reviewed. Three methods of estimating biochemical concentrations of vegetation were included in this paper: index, stepwise multiple linear regression, and stepwise multiple linear regression based on a model of the forest crown. In addition, the vitality and potential applying value are stressed.

  15. Approaches to Chemical and Biochemical Information and Signal Processing

    Science.gov (United States)

    Privman, Vladimir

    2012-02-01

    We outline models and approaches for error control required to prevent buildup of noise when ``gates'' and other ``network elements'' based on (bio)chemical reaction processes are utilized to realize stable, scalable networks for information and signal processing. We also survey challenges and possible future research. [4pt] [1] Control of Noise in Chemical and Biochemical Information Processing, V. Privman, Israel J. Chem. 51, 118-131 (2010).[0pt] [2] Biochemical Filter with Sigmoidal Response: Increasing the Complexity of Biomolecular Logic, V. Privman, J. Halamek, M. A. Arugula, D. Melnikov, V. Bocharova and E. Katz, J. Phys. Chem. B 114, 14103-14109 (2010).[0pt] [3] Towards Biosensing Strategies Based on Biochemical Logic Systems, E. Katz, V. Privman and J. Wang, in: Proc. Conf. ICQNM 2010 (IEEE Comp. Soc. Conf. Publ. Serv., Los Alamitos, California, 2010), pages 1-9.

  16. Decoupling of Growth from Production of Biochemicals and Proteins

    DEFF Research Database (Denmark)

    Li, Songyuan

    tyrosine and mevalonate, was achieved through this type of growth limitation. Second, rationally designed genetic growth switches, based on CRISPR interference (CRISPRi) systems, have been developed. By switching off cell growth during production, the production of biochemicals and proteins, exemplified...

  17. Click Chemistry-Mediated Nanosensors for Biochemical Assays

    OpenAIRE

    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 nanopro...

  18. Correlations between female breast density and biochemical markers

    OpenAIRE

    Kim, Ji-Hye; Lee, Hae-Kag; Cho, Jae-Hwan; Park, Hyong-Keun; Yang, Han-Jun

    2015-01-01

    [Purpose] The aim of this study was to identify biochemical markers related to breast density. The study was performed with 200 patients who received mammography and biochemical marker testing between March 1, 2014 to October 1, 2014. [Subjects and Methods] Following the American College of Radiology, Breast Imaging Reporting and Data System (ACR BI-RADS), breast parenchymal pattern density from mammography was categorized into four grades: grade 1, almost entirely fat; grade 2, fibroglandula...

  19. Mechanistic approaches to the study of evolution: the functional synthesis

    OpenAIRE

    Dean, Antony M; Joseph W Thornton

    2007-01-01

    An emerging synthesis of evolutionary biology and experimental molecular biology is providing much stronger and deeper inferences about the dynamics and mechanisms of evolution than were possible in the past. The new approach combines statistical analyses of gene sequences with manipulative molecular experiments to reveal how ancient mutations altered biochemical processes and produced novel phenotypes. This functional synthesis has set the stage for major advances in our understanding of fun...

  20. Exploring the evolution of protein function in Archaea

    OpenAIRE

    Goncearenco Alexander; Berezovsky Igor N

    2012-01-01

    Abstract Background Despite recent progress in studies of the evolution of protein function, the questions what were the first functional protein domains and what were their basic building blocks remain unresolved. Previously, we introduced the concept of elementary functional loops (EFLs), which are the functional units of enzymes that provide elementary reactions in biochemical transformations. They are presumably descendants of primordial catalytic peptides. Results We analyzed distant evo...

  1. Recent Advances in Shell Evolution with Shell-Model Calculations

    CERN Document Server

    Utsuno, Yutaka; Tsunoda, Yusuke; Shimizu, Noritaka; Honma, Michio; Togashi, Tomoaki; Mizusaki, Takahiro

    2014-01-01

    Shell evolution in exotic nuclei is investigated with large-scale shell-model calculations. After presenting that the central and tensor forces produce distinctive ways of shell evolution, we show several recent results: (i) evolution of single-particle-like levels in antimony and cupper isotopes, (ii) shape coexistence in nickel isotopes understood in terms of configuration-dependent shell structure, and (iii) prediction of the evolution of the recently established $N=34$ magic number towards smaller proton numbers. In any case, large-scale shell-model calculations play indispensable roles in describing the interplay between single-particle character and correlation.

  2. Analysis of clinical and biochemical spectrum of Wilson Disease patients

    Directory of Open Access Journals (Sweden)

    Sumreena Mansoor

    2012-01-01

    Full Text Available Background and Aims: Wilson disease (WD is autosomal recessive disorder of copper metabolism. Wilson disease patients usually suffer from hepatic or neuropsychiatric complications. The symptoms appear between ages five to 35 but it can vary from two years to 72 years. Materials and Methods : Study was carried out from June 2008 to November 2010. This study included nine families with eleven cases of WD to determine clinical presentation, diagnostic findings (including laboratory results and liver histology. It included 11 patients who presented with hepatic manifestations and/or Neuropsychiatric manifestations and/or family history suggesting features of WD. Patients with hepatitis B and C and those with history of taking antipsychotic drugs were excluded from the study. Patient′s data was included in a well designed performa. Liver function test, serum ceruloplasmin, serum copper, 24 hour urinary copper, blood complete picture were analyzed. Quantitative data such as age, hemoglobin etc were expressed as mean with ± SD and quantitative variables such as sex, movement disorders, hepatic involvement etc were expressed as frequency and percentage. Results: There were five male and six female patients with evidence of various manifestations here (i hepatic in which they had only liver dysfunction (ii hepatic and neurological (iii neurological. The mean age of presentation was 8.7±3.92 years (range 4-19 years and 45% were male patients. Decreased serum ceruloplasmin, enhanced 24-h urinary copper excretion and signs of chronic liver damage were confirmed in all patients and Kayser-Fleischer rings (KF rings in 72% of patients. In severe WD patients, serum prothrombin activity was less than 50%, serum ceruloplasmin were low and serum copper levels were high than those in non-severe WD patients. High degree of suspicion leads to early treatment with good outcome. Conclusions: The WD is rare but important cause of chronic liver disease. Clinical and

  3. Clinical, endocrinological and biochemical effects of zinc deficiency.

    Science.gov (United States)

    Prasad, A S

    1985-08-01

    The essentiality of zinc for humans was recognized in the early 1960s. The causes of zinc deficiency include malnutrition, alcoholism, malabsorption, extensive burns, chronic debilitating disorders, chronic renal disease, certain diuretics, the use of chelating agents such as penicillamine for Wilson's disease, and genetic disorders such as acrodermatitis enteropathica and sickle cell disease. The requirement of zinc is increased in pregnancy and during the growing age period. The clinical manifestations in severe cases of zinc deficiency included bullous-pustular dermatitis, alopecia, diarrhoea, emotional disorder, weight loss, intercurrent infections, hypogonadism in males and it is fatal if untreated. A moderate deficiency of zinc is characterized by growth retardation and delayed puberty in adolescents, hypogonadism in males, rough skin, poor appetite, mental lethargy, delayed wound healing, taste abnormalities and abnormal dark adaptation. In mild cases of zinc deficiency in human subjects, we have observed oligospermia, slight weight loss and hyperammonaemia. Zinc is a growth factor. As a result of its deficiency, growth is affected adversely in many animal species and in man. Inasmuch as zinc is needed for protein and DNA synthesis and cell division, it is believed that the growth effect of zinc is related to its effect on protein synthesis. Testicular functions are affected adversely as a result of zinc deficiency in both humans and experimental animals. This effect of zinc is at the end organ level and the hypothalamic--pituitary axis is intact in zinc-deficient subjects. Inasmuch as zinc is intimately involved in a cell division, its deficiency may adversely affect testicular size and thus its function. In mice, the incidence of degenerate oocytes, and hypohaploidy and hyperhaploidy in metaphase II oocytes were increased due to zinc deficiency. Zinc at physiological concentrations reduced prolactin secretion from the pituitary in vitro and it has been

  4. Evolution of plant senescence

    Directory of Open Access Journals (Sweden)

    Young Mike

    2009-07-01

    characteristics of senescence-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.

  5. Correlation between ovarian morphology and biochemical and hormonal parameters in polycystic ovary syndrome

    Science.gov (United States)

    Inan, Cihan; Karadag, Cihan

    2016-01-01

    Objective: To determine the biochemical and hormonal differences in polycystic ovary syndrome (PCOS) patients with and without polycystic ovary (PCO) morphology and to evaluate the outcomes resulting from those differences. Methods: The study included a total of 83 patients with PCOS; 43 of them had PCO morphology (Group-I) and 40 did not (Group-II). Serum LDL, HDL, total cholesterol, triglyceride (TG), total testosterone (T), follicle stimulating hormone (FSH), luteinizing hormone (LH), 17b-estradiol (E2), prolactin (PRL), thyroid stimulating hormone (TSH), sex hormone binding globulin (SHBG), glucose and insulin levels were determined. Homoeostatic model assessment insulin resistance (HOMA-IR) index was calculated. Results: The two groups were similar with respect to BMI. The systolic and diastolic blood pressure measurements of Group-I were significantly lower (p<0.01). Serum mean level of LH (p=0.026) and the mean LH/FSH (p=0.001) level of Group-I were significantly higher than Group-II. The total cholesterol and triglyceride levels of Group-I were significantly lower (p<0.05, p<0.01). The mean HOMA-IR level of Group-I was significantly lower than Group-II (p=0.004). Conclusions: The group without PCO morphology had a higher risk than the other group in terms of increased insulin resistance, dyslipidemia and cardiovascular diseases due to effects of hyperandrogenism. PMID:27375725

  6. Biochemical evaluation of the renin-angiotensin system: the good, bad, and absolute?

    Science.gov (United States)

    Chappell, Mark C

    2016-01-15

    The renin-angiotensin system (RAS) constitutes a key hormonal system in the physiological regulation of blood pressure through peripheral and central mechanisms. Indeed, dysregulation of the RAS is considered a major factor in the development of cardiovascular pathologies, and pharmacological blockade of this system by the inhibition of angiotensin-converting enzyme (ACE) or antagonism of the angiotensin type 1 receptor (AT1R) offers an effective therapeutic regimen. The RAS is now defined as a system composed of different angiotensin peptides with diverse biological actions mediated by distinct receptor subtypes. The classic RAS comprises the ACE-ANG II-AT1R axis that promotes vasoconstriction; water intake; sodium retention; and increased oxidative stress, fibrosis, cellular growth, and inflammation. In contrast, the nonclassical RAS composed primarily of the ANG II/ANG III-AT2R and the ACE2-ANG-(1-7)-AT7R pathways generally opposes the actions of a stimulated ANG II-AT1R axis. In lieu of the complex and multifunctional aspects of this system, as well as increased concerns on the reproducibility among laboratories, a critical assessment is provided on the current biochemical approaches to characterize and define the various components that ultimately reflect the status of the RAS.

  7. Development of a system for characterizing biomass quality of lignocellulosic feedstocks for biochemical conversion

    Science.gov (United States)

    Murphy, Patrick Thomas

    The purpose of this research was twofold: (i) to develop a system for screening lignocellulosic biomass feedstocks for biochemical conversion to biofuels and (ii) to evaluate brown midrib corn stover as feedstock for ethanol production. In the first study (Chapter 2), we investigated the potential of corn stover from bm1-4 hybrids for increased ethanol production and reduced pretreatment intensity compared to corn stover from the isogenic normal hybrid. Corn stover from hybrid W64A X A619 and respective isogenic bm hybrids was pretreated by aqueous ammonia steeping using ammonium hydroxide concentrations from 0 to 30%, by weight, and the resulting residues underwent simultaneous saccharification and cofermentation (SSCF) to ethanol. Dry matter (DM) digested by SSCF increased with increasing ammonium hydroxide concentration across all genotypes (P>0.0001) from 277 g kg-1 DM in the control to 439 g kg-1 DM in the 30% ammonium hydroxide pretreatment. The bm corn stover materials averaged 373 g kg-1 DM of DM digested by SSCF compared with 335 g kg-1 DM for the normal corn stover (Pcell-wall carbohydrate hydrolysis of corn stover, (ii) the lowest initial cell-wall carbohydrate concentration, (iii) the lowest dry matter remaining after pretreatment, and (iv) the highest amount of monosaccharides released during enzymatic hydrolysis. However, bm corn stover did not reduce the severity of aqueous ammonia steeping pretreatment needed to maximize DM hydrolysis during SSCF compared with normal corn stover. In the remaining studies (Chapters 3 thru 5), a system for analyzing the quality of lignocellulosic biomass feedstocks for biochemical conversion to biofuels (i.e., pretreatment, enzymatic hydrolysis, and fermentation) was developed. To accomplish this, a carbohydrate availability model was developed to characterize feedstock quality. The model partitions carbohydrates within a feedstock material into fractions based on their availability to be converted to fermentable

  8. Mathematical models of ecology and evolution

    DEFF Research Database (Denmark)

    Zhang, Lai

    2012-01-01

    dynamics but as a trade-o promotes species survival by shortening juvenile delay between birth and the onset of reproduction. Paper II compares the size-spectrum and food-web representations of communities using two traits (body size and habitat location) based unstructured population model of Lotka......) based size-structured population model, that is, interference in foraging, maintenance, survival, and recruitment. Their impacts on the ecology and evolution of size-structured populations and communities are explored. Ecologically, interference aects population demographic properties either negatively...... interference mechanisms, survival interference is more likely to produce large communities with complex trophic patterns through gradual evolution and successive speciation...

  9. Biochemical investigations of yield-limitations in potatoes (Solanum tuberosum L. ) under warm tropical conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mohabir, G.

    1988-01-01

    An important factor that limits potato yields in the lowland tropics is the continuously high soil temperatures. The biochemical basis of this limitation has been investigated. A sharp temperature optimum is observed in Arrhenius plots at 21.5/degrees/C when the incorporation of (/sup 14/C) sucrose into starch is measured with discs cut from developing tubers of potato. Over the same temperature range evolution of (/sup 14/C) CO/sub 2/ and apoplastic uptake show positive linearity while ethanol-soluble uptake displays a broad optimum above 25/degrees/C. By comparison starch synthesis in discs from corms of cocoyam (Colocasia esculenta (L) Schott.) is increased linearly by raising the temperature from 15/degrees/C to 35/degrees/C. The significance of a relatively low temperature optimum for starch synthesis in potato is discussed in relation to the yield limitation imposed by continuously high soil temperatures.

  10. Biochemical and histological characterization of tomato mutants

    Directory of Open Access Journals (Sweden)

    Carolina C. Monteiro

    2012-06-01

    Full Text Available Biochemical responses inherent to antioxidant systems as well morphological and anatomical properties of photomorphogenic, hormonal and developmental tomato mutants were investigated. Compared to the non-mutant Micro-Tom (MT, we observed that the malondialdehyde (MDA content was enhanced in the diageotropica (dgt and lutescent (l mutants, whilst the highest levels of hydrogen peroxide (H2O2 were observed in high pigment 1 (hp1 and aurea (au mutants. The analyses of antioxidant enzymes revealed that all mutants exhibited reduced catalase (CAT activity when compared to MT. Guaiacol peroxidase (GPOX was enhanced in both sitiens (sit and notabilis (not mutants, whereas in not mutant there was an increase in ascorbate peroxidase (APX. Based on PAGE analysis, the activities of glutathione reductase (GR isoforms III, IV, V and VI were increased in l leaves, while the activity of superoxide dismutase (SOD isoform III was reduced in leaves of sit, epi, Never ripe (Nr and green flesh (gf mutants. Microscopic analyses revealed that hp1 and au showed an increase in leaf intercellular spaces, whereas sit exhibited a decrease. The au and hp1 mutants also exhibited a decreased in the number of leaf trichomes. The characterization of these mutants is essential for their future use in plant development and ecophysiology studies, such as abiotic and biotic stresses on the oxidative metabolism.Neste trabalho, analisamos as respostas bioquímicas inerentes ao sistema antioxidante, assim como propriedades morfológicas e anatômicas de mutantes fotomorfogenéticos e hormonais de tomateiro. Comparados ao não mutante Micro-Tom (MT, observamos que o conteúdo de malondialdeído (MDA aumentou nos mutantes diageotropica (dgt e lutescent (l, enquanto os maiores níveis de H2O2 foram encontrados nos mutantes high pigment 1 (hp1 e aurea (au. Análises de enzimas antioxidantes mostraram que todos os mutantes reduziram a atividade de catalase (CAT quando comparado a MT. A

  11. BIOCHEMICAL STUDIES ON NIGERIAN MONODORA TENUIFOLIA SEED

    Directory of Open Access Journals (Sweden)

    Ekeanyanwu Raphael Chukwuma

    2013-01-01

    Full Text Available The nutritive constituents of the seeds of Monodora tenuifolia were analyzed to augment the available information on Monodora tenuifolia research. Blood glucose and lipid profile were investigated on the flavonoid rich fraction of M. tenuifolia in rats. The composition (gkg-1 of alkaloids, cyanogenic glycosides, tannins and flavonoids were 13.3±0.1, 21.2×10-2±0.6, 1.3±0.1, 1.7±0.1 and 11.7±1.1 respectively. The proximate composition (gkg-1 of M. tenuifolia seed were crude fibre (262.3±1.2, crude protein (82.6±1.0, crude fat (349.9±1.9, ash (49.9±0.6, moisture (190.0±0.00 and carbohydrate (65.5±4.7. Analysis of the minerals content (gkg-1 yielded calcium (864.0±29.38, sodium (2752.0±140.35, iron (3.34±0.06, zinc (5.26±0.08, potassium (326.4±13.06, magnesium (342.9±13.71 and phosphorus (9.52±0.17, while vitamin analysis yielded vitamin A (10.05±0.17 iu/100 g, C (56.40±0.14 gkg-1 and E (11.71±0.87 iu /100 g, thiamine (0.11±0.01 gkg-1, niacin (0.46±0.32 gkg-1 and riboflavin (0.04±0.01 gkg-1. The results of amino acid analysis showed the total amino acid of M. tenuifolia seed was 71.78 of crude protein. The total essential amino acid with Histidine was calculated to be 29.24 of the crude protein. The antinutrient analysis of M. tenuifolia shows it contained total phenol (0.8±0.0 gkg-1, oxalates (4.09±1.17 gkg-1, phytates (0.012±0.42 gkg-1 and trypsin inhibitor (0.230±0.42 iu/g. The main fatty acids of the seed oil are linoleic acid (401.7 g kg-1, oleic acid (346.1 g kg-1 and palmitic acid (122.61 g kg-1. The LD50 of the flavonoid-rich fraction was found to be above 5000 mg kg-1 b.w. After the day 14 study, biochemical markers such as triacylglycerol, very low density lipoprotein increased significantly (p0.05 effect was observed on the blood glucose and lipid profile of wistar albino rats compared with the control. The result shows that M. tenuifolia seed is rich

  12. Early evolution stage of AGN

    Science.gov (United States)

    Kunert-Bajraszewska, M.; Labiano, A.; Siemiginowska, A.; Guainazzi, M.; Gawroński, M.

    2015-03-01

    Radio sources are divided into two distinct morphological groups of objects: Fanaroff-Riley type I and type II sources. There is a relatively sharp luminosity boundary between these at low frequency. The nature of the FR division is still an open issue, as are the details of the evolutionary process in which younger and smaller GHz-peaked spectrum (GPS) and compact steep spectrum (CSS) sources become large-scale radio structures. It is still unclear whether FRII objects evolve to become FRIs, or whether a division has already occurred amongst CSS sources and some of these then become FRIs and some FRIIs. We explored evolution scenarios of AGNs using new radio, optical and X-ray data of unstudied so far Low Luminosity Compact (LLC) sources. We suggest that the determining factors of the further evolution of compact radio objects could occur at subgalactic (or even nuclear) scales, or they could be related to the radio jet - interstellar medium (ISM) interactions and evolution. Our studies show that the evolutionary track could be related to the interaction, strength of the radio source and excitation levels of the ionized gas instead of the radio morphology of the young radio source.

  13. Adaptive Evolution of the Venom-Targeted vWF Protein in Opossums that Eat Pitvipers

    OpenAIRE

    Sharon A Jansa; Voss, Robert S.

    2011-01-01

    The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae) and pitvipers (Serp...

  14. The Evolution of Protein Structures and Structural Ensembles Under Functional Constraint

    OpenAIRE

    Liberles, David A; Grahnen, Johan A.; Jessica Siltberg-Liberles

    2011-01-01

    Protein sequence, structure, and function are inherently linked through evolution and population genetics. Our knowledge of protein structure comes from solved structures in the Protein Data Bank (PDB), our knowledge of sequence through sequences found in the NCBI sequence databases (http://www.ncbi.nlm.nih.gov/), and our knowledge of function through a limited set of in-vitro biochemical studies. How these intersect through evolution is described in the first part of the review. In the secon...

  15. Potential impact of gene regulatory mechanisms on the evolution of multicellularity in the volvocine algae

    OpenAIRE

    Kianianmomeni, Arash

    2015-01-01

    A fundamental question in biology is how multicellular organisms can arise from their single-celled precursors. The evolution of multicellularity requires the adoption of new traits in unicellular ancestors that allows the generation of form by, for example, increasing the size and developing new cell types. But what are the genetic, cellular and biochemical bases underlying the evolution of multicellularity? Recent advances in evolutionary developmental biology suggest that the regulation of...

  16. Cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II) and dioxouranium(II) complexes of thiophene-2-aldehyde-4-phenyl-thiosemicarbazone

    International Nuclear Information System (INIS)

    The present paper describes the synthesis and characterisation of thiophene-2-aldehyde-4-phenylthiosemicarbazone (TAPTSC) and its metal complexes with Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and UO(II). (author). 30 refs., 1 table

  17. Haemato-biochemical alterations induced by lead acetate toxicity in wistar rats

    Directory of Open Access Journals (Sweden)

    S. G. Suradkar

    Full Text Available An experiment was conducted to study the haemato-biochemical alterations induced by lead acetate toxicity in 48 Wistar rats of either sex, divided uniformly into four different groups. The rats of group I received only deionised water as control while, group II, III and IV were given lead acetate @ 1 PPM, 100 PPM and 1000 PPM, in drinking deionised water respectively for 28 days. In group III and IV dose dependant significant (P<0.05 reductions in TEC, Hb, PCV and TLC were observed. No significant change was observed in neutrophil, eosinophil, basophil and monocyte count in any treatment groups, whereas the lymphocyte count decreased significantly (P<0.05 in group III and IV. A dose dependant significant (P<0.05 increase in AST, ALP, AKP, GGT, BUN and creatinine was experiential while TP and albumin levels were decreased in group III and IV. [Vet World 2009; 2(11.000: 429-431

  18. Effect of induced epilepsy on some biochemical parameters in female rats

    Directory of Open Access Journals (Sweden)

    J.S. H. Ali

    2012-01-01

    Full Text Available The activity of cholinesterase and some biochemical parameters of blood such as glucose, cholesterol and phospholipids were estimated in 52 epilepsy induced females of Wister albino rats. Animals of this experiment were divided into two groups, group (I regarded as control and group (II administrated subcutaneously by pentylenetetrazole 100mg/kg and divided in to three sub-groups according to the time of samples collection 3 hrs, 24 hrs and 1 week. The results revealed that epilepsy induction caused a significant inhibition of serum cholinesterase activity 3 hrs after induction while in the brain, the activity of cholinesterase was significantly increased after 24 hrs Serum glucose level was significantly elevated after 3 hrs and 24 hrs of induction, total cholesterol and phospholipids were not changed. From the results obtained in this study, it can be concluded that epilepsy caused significant changes in cholinesterase activity in brain and serum in addition to the glucose level in the serum.

  19. Lonomia genus caterpillar toxins: biochemical aspects.

    Science.gov (United States)

    Arocha-Piñango, C L; Marval, E; Guerrero, B

    2000-01-01

    In 1967 we reported for the first time five cases of an acquired bleeding disorder in humans which developed after contact with saturnidae caterpillars. Since that time, other cases have been reported in Brazil, French Guyana, Peru, Paraguay and Argentina. The caterpillars have been identified as Lonomia achelous (LA) in Venezuela and northern Brazil and as Lonomia obliqua (LO) in southern Brazil. All patients present pain and a burning sensation at the site of contact. Within a few hours hematomas and hematuria are seen in combination with intracerebral and intraperitoneal hemorrhage (in some cases also renal failure). Hematological tests show: mild anemia with leucocytosis; prolonged PT, PTT and ThT; decreased fibrinogen, factor V, factor XIII, plasminogen and alpha2-antiplasmin levels; increased factor VIII:c, von Willebrand factor, and FDPs/D-dimers levels with normal ATIII and platelets. Factor VII, factor II and PC levels varied. Several activities similar to or directed against blood clotting factors have been identified in LA: fibrinolytic enzymes, which degrade fibrinogen producing abnormal FDPs; prothrombin activators: one direct and one factor Xa-like; a thermostable factor V activator; a thermolabile factor V inhibitor; a factor XIII proteolytic/urokinase-like activity; and a kallikrein-like activitiy. In LO three activities have been described: a prothrombin activator called 'Lonomia obliqua prothrombin activator protease' (LOPAP); a factor X activator; and a phospholipase A(2)-like activity called Lonomiatoxin. No fibrinolytic activity has been described in LO. Subcutaneous injection of crude hemolymph and some chromatographic fractions of LA induce a decrease in fibrinogen, plasminogen and factor XIII. Intravenous injection of factor XIII proteolytic/urokinase-like activity induce a dose-dependent thrombolysis with a decrease in plasmatic factor XIII without hemorrhagic manifestations. Intradermal injection of LO bristle extracts in rats and rabbits

  20. Effects of Training Load on Some Hormonal, Hematological and Biochemical Profile of Male Cyclists

    Directory of Open Access Journals (Sweden)

    Pralay Majumdar

    2014-07-01

    Full Text Available Hematological profiles of cyclists fluctuates are based on the volume/frequency/intensity of training. The present study examined the effects of training load on the cyclist’s biochemical profile which may be associated with over training. Twelve male cyclists volunteered to participate in this study. The participants completed a systematic training program which was divided into four phases i.e. phase I (560 km, continuous aerobic training, II (680 km, continuous aerobic training, III (720 km, aerobic and anaerobic interval training and IV (560 km, continuous aerobic training. Blood samples were collected at the end of each phase. The hemoglobin level of the cyclists increased throughout the training cycle whereas iron level increased till the third phase and decreased in the fourth phase due to alteration in training. Hemoglobin level was high during the IV phase and this was due to the lowest volume/frequency of training given to the cyclists in final phase. Total Iron Binding Capacity (TIBC level was elevated during the competitive phase, due to the high volume / intensity during III phase. The depletion of ferritin was high during phase II which was associated with a 21% increase in training volume after the first phase. The highest intensity, volume and frequency of E2S training (phase III were associated with a large increase in Creatine Phosphokinase (CPK, Lactate Dehydrogenase (LDH and cortisol levels, demonstrating a significant decrease in testosterone that showed the over-trained state. Hence, these biochemical markers are important in monitoring athlete’s training load as these parameters are altered with the training intensity, frequency and volume of training given to the cyclist.

  1. Chemical Evolution of the Juvenile Universe

    CERN Document Server

    Wasserburg, G J

    2009-01-01

    Only massive stars contribute to the chemical evolution of the juvenile universe corresponding to [Fe/H]-0.32. Recent observations show that there are stars with [Sr/Fe]<-2 and [Fe/H]<-3. This proves that the two-component model is not correct and that a third component is necessary to explain the observations. This leads to a simple three-component model including low-mass and normal SNe II and hypernovae (HNe), which gives a good description of essentially all the data for stars with [Fe/H]<-1.5. We conclude that HNe are more important than normal SNe II in the chemical evolution of the low-A elements, in sharp distinction to earlier models. (Abridged)

  2. A critical appraisal of the phene-plate biochemical fingerprinting system for epidemiological subtyping of Salmonella typhimurium

    DEFF Research Database (Denmark)

    On, S.L.W.; Baggesen, Dorte Lau

    1996-01-01

    P-types which are epidemiologically unjustified, (ii) tests currently recommended for PhP-typing S. typhimurium may be somewhat unstable and not satisfactory for fingerprinting purposes, (iii) caution must be exercised when comparing data from different batches of PhP-48 plates, and (iv) best results......The efficacy and reproducibility of the Phene-Plate (PhP) system (Biosys Inova, Stockholm, Sweden) for biochemical fingerprinting of Salmonella typhimurium was investigated. Duplicate and replicate assays on 40 epidemiologically related and unrelated strains were performed in two batches of PhP-48...

  3. Biochemical characterisation during seed development of oil palm (Elaeis guineensis).

    Science.gov (United States)

    Kok, Sau-Yee; Namasivayam, Parameswari; Ee, Gwendoline Cheng-Lian; Ong-Abdullah, Meilina

    2013-07-01

    Developmental biochemical information is a vital base for the elucidation of seed physiology and metabolism. However, no data regarding the biochemical profile of oil palm (Elaeis guineensis Jacq.) seed development has been reported thus far. In this study, the biochemical changes in the developing oil palm seed were investigated to study their developmental pattern. The biochemical composition found in the seed differed significantly among the developmental stages. During early seed development, the water, hexose (glucose and fructose), calcium and manganese contents were present in significantly high levels compared to the late developmental stage. Remarkable changes in the biochemical composition were observed at 10 weeks after anthesis (WAA): the dry weight and sucrose content increased significantly, whereas the water content and hexose content declined. The switch from a high to low hexose/sucrose ratio could be used to identify the onset of the maturation phase. At the late stage, dramatic water loss occurred, whereas the content of storage reserves increased progressively. Lauric acid was the most abundant fatty acid found in oil palm seed starting from 10 WAA.

  4. Evolution & Diversity in Plants.

    Science.gov (United States)

    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)

  5. Biochemical and immunohistochemical characterization of proteins in Hürthle cell carcinoma.

    Science.gov (United States)

    De Keyser, L; Layfield, L; Van Herle, A; Costin, A; Lewin, K

    1984-10-01

    The present study reports the biochemical and immunohistochemical findings in the cytosol of a Hürthle cell carcinoma as compared with that of normal thyroid tissue. Sephadex G-200 chromatography of the extract derived from a Hürthle cell carcinoma and from normal thyroid tissue revealed three identical pools. Pool I consisted mainly of thyroglobulin (Tg), pool II corresponded to albumin, while pool III contained unidentified low molecular weight fragments which could not be studied further. Hürthle cell carcinoma, pool I, had a Tg content of 12.9 micrograms Tg/mg equivalent tissue and a 127I content of 5,6 mole/mole of Tg. Its sialic acid content was undetectable, however. In pool I of the normal thyroid gland, the respective values were 62.8 micrograms Tg/mg equivalent tissue, 21.3 +/mole 127I/mole Tg, and 15.4 mole sialic acid/mole Tg. The albumin contained in both pools II was shown to be ioidinated at the following levels: 0.025 mole 127I/mole albumin in Hürthle tumor pool II vs 1.28 mole 127I/mole albumin in normal thyroid pool II. Immunohistochemical studies confirmed the presence of Tg and albumin in the malignant Hürthle cells and acini and colloid. Thus, Hürthle cell carcinoma contained Tg and albumin. The Tg content was five times less compared with control tissue. Both proteins (Tg and albumin) were poorly iodinated in Hürthle carcinoma tissue, and the iodination of albumina seemed to be more severely impaired. The site of synthesis of both proteins could not be derived from the present studies. PMID:6392400

  6. FeII/MgII Emission Line Ratio in High Redshift Quasars

    DEFF Research Database (Denmark)

    Dietrich, M.; Hamann, F.; Appenzeller, I.;

    2003-01-01

    We present results of the analysis of near infrared spectroscopic observations of 6 high-redshift quasars (z > 4), emphasizing the measurement of the ultraviolet FeII/MgII emission line strength in order to estimate the beginning of intense star formation in the early universe. To investigate the...... evolution of the FeII/MgII ratio over a wider range in cosmic time, we measured this ratio for composite quasar spectra which cover a redshift range of 0 4 quasars must have started already at an epoch corresponding to z_f = 6 to 9, when the age of the universe was ~0.5 Gyr (H_o = 72 km/s/Mpc, Omega_M = 0...

  7. SABRE: A Tool for Stochastic Analysis of Biochemical Reaction Networks

    CERN Document Server

    Didier, Frederic; Mateescu, Maria; Wolf, Verena

    2010-01-01

    The importance of stochasticity within biological systems has been shown repeatedly during the last years and has raised the need for efficient stochastic tools. We present SABRE, a tool for stochastic analysis of biochemical reaction networks. SABRE implements fast adaptive uniformization (FAU), a direct numerical approximation algorithm for computing transient solutions of biochemical reaction networks. Biochemical reactions networks represent biological systems studied at a molecular level and these reactions can be modeled as transitions of a Markov chain. SABRE accepts as input the formalism of guarded commands, which it interprets either as continuous-time or as discrete-time Markov chains. Besides operating in a stochastic mode, SABRE may also perform a deterministic analysis by directly computing a mean-field approximation of the system under study. We illustrate the different functionalities of SABRE by means of biological case studies.

  8. Click Chemistry-Mediated Nanosensors for Biochemical Assays

    Science.gov (United States)

    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

  9. The Development of a Biochemical Profile of Acacia Honey by Identifying Biochemical Determinants of its Quality

    Directory of Open Access Journals (Sweden)

    Liviu Alexandru MARGHITAS

    2010-09-01

    Full Text Available Codex Alimentarius Standard, EU Legislation and National Standards state honey authenticity. Authenticity in respect of production (to prevent adulteration and authenticity in respect of geographical and botanical origin are the two main aspects of general honey authenticity. Quality of honey depends on the plant source, the chemical composition of these plants as well, as on the climatic conditions and soil mineral composition. Romanian acacia (Robinia pseudoacacia honey that came from the most important Transylvanian massif (Valea lui Mihai, Bihor County, Romania was evaluated for authenticity by pollen-analysis, several physico-chemical analyses, including sugar profile and mineral content. As polyphenolic content could be also an important factor for botanical authentification, HPLC-DAD-MS analyses were performed to assess the fingerprint of this important secondary plant metabolite. Statistical data were processed in order to develop a biochemical profile of this type of honey and the main quality categories identification. The results of physico-chemical analysis demonstrated that the tested honey samples could be framed into monofloral type of acacia honeys. The analysis of acacia honeys originating from Valea lui Mihai, Romania, showed that polyphenolic profile (phenolic acids and flavonoids could be used as a complementary method for authenticity determination together with pollen analysis and other physico-chemical analysis.

  10. Galactic chemical evolution hydrogen through zinc

    CERN Document Server

    Timmes, F X; Timmes, F X; Woosley, S E

    1994-01-01

    Using the output from a grid of 60 Type II supernova models (Woosley \\& Weaver 1994) of varying mass (11 \\ltaprx M/M\\sun \\ltaprx 40) and metallicity (0, 10^{-4}, 0.01, 0.1, and 1 Z\\sol), the chemical evolution of 76 stable isotopes, from hydrogen to zinc, is calculated. The chemical evolution calculation employs a simple dynamical model for the Galaxy (infall with a 4 billion year e-folding time scale onto a exponential disk and 1/r^2 bulge), and standard evolution parameters, such as a Salpeter initial mass function and a quadratic Schmidt star formation rate. The theoretical results are compared in detail with observed stellar abundances in stars with metallicities in the range -3.0 \\ltaprx [Fe/H] \\ltaprx 0.0 dex. While our discussion focuses on the solar neighborhood where there are the most observations, the supernovae rates, an intrinsically Galactic quantity, are also discussed.

  11. Chemical Evolution models of Local Group galaxies

    CERN Document Server

    Tosi, M P

    2003-01-01

    Status quo and perspectives of standard chemical evolution models of Local Group galaxies are summarized, discussing what we have learnt from them, what we know we have not learnt yet, and what I think we will learn in the near future. It is described how Galactic chemical evolution models have helped showing that: i) stringent constraints on primordial nucleosynthesis can be derived from the observed Galactic abundances of the light elements, ii) the Milky Way has been accreting external gas from early epochs to the present time, iii) the vast majority of Galactic halo stars have formed quite rapidly at early epochs. Chemical evolution models for the closest dwarf galaxies, although still uncertain so far, are expected to become extremely reliable in the nearest future, thanks to the quality of new generation photometric and spectroscopic data which are currently being acquired.

  12. Amphioxus: a peaceful anchovy fillet to illuminate Chordate Evolution (II)

    OpenAIRE

    Jordi Garcia-Fernàndez

    2006-01-01

    The genome of the amphioxus is on the horizon. With Linda Holland and Jeremy Gibson-Brown at the forefront, with all the amphioxus community behind, and with the Joint Genome Institute, the amphioxus genome will see the light this year, 2006. Hope that it will reflect the “prototypical” preduplicative genome of vertebrates. It may answer definitively what the human genome did not: Are we vertebrates octaploid? Will it shed light on the novelties that helped non-chordates to be cho...

  13. ROMANIAN BANKING SYSTEM EVOLUTION AND BASEL II REQUIREMENTS

    Directory of Open Access Journals (Sweden)

    Mihaela NICOLAU

    2006-01-01

    Full Text Available Before 1989, Romanian Banking System was structured in the specific way of a centralized economy. Restructuring of the banking system took its first step at the end of 1990 when the newly- established bank, Banca Comercială Română, took over retail operations performed previously by the NBR. Simultaneously, some privately-owned banking companies were established and foreign banks’ branches were integrated into the domestic banking activity, the number of banks almost trebling. The unfriendly economic environment, the poor quality of bank managers and shareholders and cumbersome legal procedures led to an increase in tensions, the poor quality of credit portfolio representing the major difficulty of the banking sector. In the past years, NBR tried to control more thebanking activity by implementing international settlements. More over, since Romania is one of the European Union countries, it is absolutely necessary the harmonization of entire economic and financial system to EU regulations. The paper try to present the position of Romanian banking system in the framework of all these transformations.

  14. Inner complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Be(II) and dioxouranium(VI) with salicylaldehyde semicarbazone

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, P.L.; Agarwala, B.V.; Dey, A.K. (Allahabad Univ. (India). Dept. of Chemistry)

    1980-08-01

    Salicylaldehyde semicarbazone (SALSC), yields complexes, ML/sub 2/.2H/sub 2/O (M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)) and ML/sub 2/ (M = Be(II) and UO/sub 2/(VI)). The complexes have been characterized by analytical, spectral, magnetic and thermogravimetric studies. SALSC acts as a singly negatively charged bidentate anion, and two such anions coordinate to the metal ion through the hydroxyl oxygen and nitrogen of the C = N group yielding a neutral chelate. The complexes of Co(II), Ni(II) and Cu(II) are paramagnetic with magnetic moment values 4.93, 3.35 and 1.98 BM, respectively. The magnetic and spectral data suggest octahedral geometry of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and UO/sub 2/(VI) complexes, whereas the Be(II) complex is tetrahedral. TG study reveals the order of thermal stability as : Zn(II) approximately equal to Ni(II) >Be(II) approximately equal to Cd(II) > UO/sub 2/(VI) approximately equal to Co(II) approximately equal to Cu(II).

  15. Structure and Function of Cu(I)- and Zn(II)-ATPases

    DEFF Research Database (Denmark)

    Sitsel, Oleg; Grønberg, Christina; Autzen, Henriette Elisabeth;

    2015-01-01

    membranes at the expense of ATP. Recent biochemical studies and crystal structures have significantly improved our understanding of the transport mechanisms of these proteins, but many details about their structure and function remain elusive. Here we compare the Cu(I)- and Zn(II)-ATPases, scrutinizing...

  16. Physiological and biochemical basis of salmon young ifshes migratory behavior

    Institute of Scientific and Technical Information of China (English)

    Vladimir Ivanovich Martemyanov

    2016-01-01

    The review presents data on structural changes, physiological and biochemical reactions occurring at salmon young fishes during smoltification. It is shown, that young salmon fishes located in fresh water, in the process of smoltification undergo a complex of structural, physiological and biochemical changes directed on preparation of the organism for living in the sea. These changes cause stress reaction which excites young fishes to migrate down the river towards the sea. Measures to improve reproduction of young salmon fishes at fish farms are offered.

  17. The Biochemical Properties of Antibodies and Their Fragments.

    Science.gov (United States)

    Hnasko, Robert M

    2015-01-01

    Immunoglobulins (Ig) or antibodies are 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 class of protein will provide users with the knowledge necessary to select the appropriate antibody composition to maximize immunoassay results. Here we define the general biochemical properties of antibodies and their similarities and differences, explain how these properties influence their functional relationship to an antigen target, and describe a method for the enzymatic fragmentation of antibodies into smaller functional parts.

  18. Differential evolution in electromagnetics

    CERN Document Server

    Qing, Anyong

    2010-01-01

    Differential evolution has proven itself a very simple while very powerful stochastic global optimizer. It has been applied to solve problems in many scientific and engineering fields. This book focuses on applications of differential evolution in electromagnetics to showcase its achievement and capability in solving synthesis and design problems in electromagnetics.Topics covered in this book include:*A comprehensive up-to-date literature survey on differential evolution*A systematic description of differential evolution*A topical review on applications of differential evolution in electromag

  19. Lymphocytic Thyroiditis – is cytological grading significant? A correlation of grades with clinical, biochemical, ltrasonographic and radionuclide parameters

    Directory of Open Access Journals (Sweden)

    Dash Radharaman

    2007-01-01

    Full Text Available Abstract Background Clinical, biochemical, ultrasonographic, radionuclide and cytomorphological observations in Lymphocytic thyroiditis (LT, to define the cytological grading criteria on smears and correlation of grades with above parameters. Methods This prospective study was conducted on 76 patients attending the Fine needle aspiration cytology clinic of a tertiary care institute in North India. The various parameters like patients' clinical presentation, thyroid antimicrosomal antibodies, hormonal profiles, radionuclide thyroid scan and thyroid ultrasound were studied. Fine needle aspiration of thyroid gland and grading of thyroiditis was done on smears. The grades were correlated with above parameters and the correlation indices were evaluated statistically. Results Most of the patients were females (70, 92.11% who presented with a diffuse goiter (68, 89.47%. Hypothyroid features (56, 73.68% and elevated TSH (75, 98.68% were common, but radioiodide uptake was low or normal in majority of patients. Thyroid antimicrosomal antibody was elevated in 46/70 (65.71% patients. Cytomorphology in fine needle aspirates was diagnostic of lymphocytic thyroiditis in 75 (98.68% patients. Most of them had grade I/II disease by cytology. No correlation was observed between grades of cytomorphology and clinical, biochemical, ultrasonographic and radionuclide parameters. Conclusion Despite the availability of several tests for diagnosis of LT, FNAC remains the gold standard. The grades of thyroiditis at cytology however do not correlate with clinical, biochemical, radionuclide and ultrasonographic parameters.

  20. [Changes in the biochemical composition, structure, and function of pea leaf chloroplasts in iron deficiency and root anoxia].

    Science.gov (United States)

    Ladygin, V G

    2004-01-01

    A combined effect of iron deficiency and root anoxia on the biochemical composition, function, and structure of pea leaf chloroplasts was studied. It was found that the chlorosis of apical leaves in response to iron deficiency was determined by the reduction of light-harvesting complexes I and II. Under root anoxia, complexes of the reaction centers of photosystems I and II degraded first. Weak activity was preserved even in yellow and white leaves under the effect of both factors. The ultrastructure of leaf chloroplasts gradually degraded. Initially, intergranal thylakoid sites were reduced, and the longitudinal orientation of grana was disturbed. However, yellow and white leaves still retained small thylakoids and grana. It is concluded that the degrading effects of iron deficiency and root anoxia on the complex composition and leaf chloroplast structure and function are additive because of their autonomous mechanisms. PMID:15553792

  1. Multiplicity in Early Stellar Evolution

    CERN Document Server

    Reipurth, Bo; Boss, Alan P; Goodwin, Simon P; Rodriguez, Luis Felipe; Stassun, Keivan G; Tokovinin, Andrei; Zinnecker, Hans

    2014-01-01

    Observations from optical to centimeter wavelengths have demonstrated that multiple systems of two or more bodies is the norm at all stellar evolutionary stages. Multiple systems are widely agreed to result from the collapse and fragmentation of cloud cores, despite the inhibiting influence of magnetic fields. Surveys of Class 0 protostars with mm interferometers have revealed a very high multiplicity frequency of about 2/3, even though there are observational difficulties in resolving close protobinaries, thus supporting the possibility that all stars could be born in multiple systems. Near-infrared adaptive optics observations of Class I protostars show a lower binary frequency relative to the Class 0 phase, a declining trend that continues through the Class II/III stages to the field population. This loss of companions is a natural consequence of dynamical interplay in small multiple systems, leading to ejection of members. We discuss observational consequences of this dynamical evolution, and its influenc...

  2. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    Heart disease is by far the biggest killer in the United States, and type II diabetes, which affects 8% of the U.S. population, is on the rise. In many cases, the acute coronary syndrome and/or sudden cardiac death occurs without warning. Atherosclerosis has known behavioral, genetic and dietary risk factors. However, our laboratory studies with animal models and human post-mortem tissue using FT-IR microspectroscopy reveal the chemical microstructure within arteries and in the arterial walls themselves. These include spectra obtained from the aortas of ApoE-/- knockout mice on sucrose and normal diets showing lipid deposition in the former case. Also pre-aneurysm chemical images of knockout mouse aorta walls, and spectra of plaque excised from a living human patient are shown for comparison. In keeping with the theme of the SPEC 2008 conference Spectroscopic Diagnosis of Disease this paper describes the background and potential value of a new catheter-based system to provide in vivo biochemical analysis of plaque in human coronary arteries. We report the following: (1) results of FT-IR microspectroscopy on animal models of vascular disease to illustrate the localized chemical distinctions between pathological and normal tissue, (2) current diagnostic techniques used for risk assessment of patients with potential unstable coronary syndromes, and (3) the advantages and limitations of each of these techniques illustrated with patent care histories, related in the first person, by the physician coauthors. Note that the physician comments clarify the contribution of each diagnostic technique to imminent cardiac risk assessment in a clinical setting, leading to the appreciation of what localized intravascular chemical analysis can contribute as an add-on diagnostic tool. The quality of medical imaging has improved dramatically since the turn of the century. Among clinical non-invasive diagnostic tools, laboratory tests of body fluids, EKG, and physical examination are

  3. Eta Carinae's 2014.6 Spectroscopic Event: The Extraordinary He II and N II Features

    CERN Document Server

    Davidson, Kris; Humphreys, Roberta; Martin, John C; Ishibashi, Kazunori

    2014-01-01

    Eta Carinae's spectroscopic events (periastron passages) in 2003, 2009, and 2014 showed a progressive evolution in several respects. He II 4687 and nearby N II multiplet 5have special significance, because they are excited in unusual ways that sample very soft X-rays and the ionizing UV radiation field (EUV). HST/STIS observations in 2014 show dramatic increases in both compared to the previous 2009.1 event. These results appear very consistent with a progressive decline in the primary wind density, proposed years ago on other grounds. If material falls onto the companion star near periastron, the accretion rate may now have become too low to suppress the EUV

  4. FeII/MgII, [Fe/Mg] Ratios and High-z Quasars

    CERN Document Server

    Korista, K; Corbin, M R; Freudling, W; Korista, Kirk; Kodituwakku, Nalaka; Corbin, Michael; Freudling, Wolfram

    2003-01-01

    It has been suggested in the literature that the (Fe/alpha) abundance ratio may be used as a chronometer, due to a delay in this ratio reaching its solar value as predicted by galactic chemical evolution models. Using grids of photoionization models along a sequence of the (Fe/Mg) abundance ratio vs.\\ metallicity with time in a giant elliptical starburst scenario, we investigate the relationship between the (Fe/Mg) abundance ratio and the FeII/MgII emission line flux ratio under the assumption that these lines originate in photoionized clouds within the broad emission line regions of quasars.

  5. BIOCHEMICAL CHANGES IN THE WOUNDS OF GOATS FOLLOWING TREATMENT OF SUNFLOWER OIL AND OLIVE OIL

    Directory of Open Access Journals (Sweden)

    Abhishek Anand

    2016-06-01

    Full Text Available Experimentally created forty eight wounds of similar size and shape were randomly divided in to three groups, of 16 wounds in each group. Sunflower seed oil impregnated gauze were subjected to the wounds of goats belonging to group I, while Olive oil (Olea europaea impregnated gauze were subjected to the wounds of goats of group II and normal saline solution (control soaked gauze to the wounds of goats of group III. Healing tissues were collected from the junction of wound and intact skin from all the experimental wounds in each of the three groups on 3, 10, 15 and 25 days. Biochemical examinations of healing tissue were done for collagen, elastin, hexosamine and hydroxyproline. The level of collagen, elastin, hexosamine and hydroxyproline were significantly higher in group I followed by group II and then group III. It can be concluded that both sunflower oil and olive oil are effective for acceleration of wound healing and sunflower oil is more effective than olive oil.

  6. Biochemical and spectroscopic characterization of the catalytic domain of MMP16 (cdMMP16).

    Science.gov (United States)

    Meng, Fan; Yang, Hao; Aitha, Mahesh; George, Sam; Tierney, David L; Crowder, Michael W

    2016-07-01

    Membrane-bound matrix metalloproteinase 16 (MMP16/MT3-MMP) is considered a drug target due to its role(s) in disease processes such as cancer and inflammation. Biochemical characterization of MMP16 is critical for developing new generation MMP inhibitors (MMPi), which exhibit high efficacies and selectivities. Herein, a modified over-expression and purification protocol was used to prepare the catalytic domain of MMP16 (cdMMP16). The resulting recombinant enzyme exhibited steady-state kinetic constants of K m = 10.6 ± 0.7 μM and k cat = 1.14 ± 0.02 s(-1), when using FS-6 as substrate, and the enzyme bound 1.8 ± 0.1 eq of Zn(II). The enzymatic activity of cdMMP16 is salt concentration-dependent, and cdMMP16 exhibits autoproteolytic activity under certain conditions, which may be related to an in vivo regulatory mechanism of MMP16 and of other membrane-type MMPs (MT-MMPs). Co(II)-substituted analogs (Co2- and ZnCo) of cdMMP16 were prepared and characterized using several spectroscopic techniques, such as UV-Vis, (1)H NMR, and EXAFS spectroscopies. A well-characterized cdMMP16 is now available for future inhibitor screening efforts. PMID:27229514

  7. Spectral imaging for measuring biochemicals in plant material

    NARCIS (Netherlands)

    Polder, G.

    2004-01-01

    The demand for high quality fruits and other plant material is increasing. New consumer demands involve taste, ripeness, and health-promoting compounds. These criteria are often related to the presence, absence and spatial distribution patterns of specific biochemical compounds in the food. This the

  8. Advances in Biochemical Screening for Phaeochromocytoma using Biogenic Amines

    OpenAIRE

    Whiting, Malcolm J; Doogue, Matthew P

    2009-01-01

    Biochemical testing for phaeochromocytoma is performed in diagnostic laboratories using a variety of tests with plasma, serum or 24-hour urine collections. These tests include catecholamines and their methylated metabolites - the metanephrines, either individually or in combination with their sulfated metabolites. High-performance liquid chromatography (HPLC) continues to be the dominant analytical method for biogenic amine quantitation. Chromatographic techniques are changing, with improveme...

  9. MATLAB-Based Teaching Modules in Biochemical Engineering

    Science.gov (United States)

    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…

  10. Biochemical aspects of pressure tolerance in marine mammals.

    Science.gov (United States)

    Castellini, Michael A; Rivera, Patricia M; Castellini, Judith M

    2002-11-01

    Some marine mammals can dive to depths approaching 2000 m. At these hydrostatic pressures (200 atm), some fish species show alterations in enzyme structure and function that make them pressure-tolerant. Do marine mammals also possess biochemical adaptations to withstand such pressures? In theory, biochemical alterations might occur at the control of enzymatic pathways, by impacting cell membrane fluidity changes or at a higher level, such as cellular metabolism. Studies of marine mammal tissues show evidence of all of these changes, but the results are not consistent across species or diving depth. This review discusses whether the elevated body temperature of marine mammals imparts pressure tolerance at the biochemical level, whether there are cell membrane structural differences in marine mammals and whether whole, living cells from marine mammals alter their metabolism when pressure stressed. We conclude that temperature alone is probably not protective against pressure and that cell membrane composition data are not conclusive. Whole cell studies suggest that marine mammals either respond positively to pressure or are not impacted by pressure. However, the range of tissue types and enzyme systems that have been studied is extremely limited and needs to be expanded before more general conclusions about how these mammals tolerate elevated pressures on a biochemical level can be drawn.

  11. Study on color difference estimation method of medicine biochemical analysis

    Science.gov (United States)

    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.

  12. Biochemical Pathways That Are Important for Cotton Fiber Cell Elongation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The regulatory mechanism that controls the sustained cotton fiber cell elongation is gradually being elucidated by coupling genome-wide transcriptome profiling with systematic biochemical and physiological studies.Very long chain fatty acids(VLCFA),H2O2,and several types of plant hormones

  13. Polynomial analysis of canopy spectra and biochemical component content inversion

    Institute of Scientific and Technical Information of China (English)

    YAN Chunyan; LIU Qiang; NIU Zheng; WANG Jihua; HUANG Wenjiang; LIU Liangyun

    2005-01-01

    A polynomial expression model was developed in this paper to describe directional canopy spectra, and the decomposition of the polynomial expression was used as a tool for retrieving biochemical component content from canopy multi-angle spectra. First, the basic formula of the polynomial expression was introduced and the physical meaning of its terms and coefficients was discussed. Based on this analysis, a complete polynomial expression model and its decomposition method were given. By decomposing the canopy spectra simulated with SAILH model, it shows that the polynomial expression can not only fit well the canopy spectra, but also show the contribution of every order scattering to the whole reflectance. Taking the first scattering coefficients a10 and a01 for example, the test results show that the polynomial coefficients reflect very well the hot spot phenomenon and the effects of viewing angles, LAI and leaf inclination angle on canopy spectra. By coupling the polynomial expression with leaf model PROSPECT, a canopy biochemical component content inversion model was given. In the simulated test, the canopy multi-angle spectra were simulated by two different models, SAILH and 4-SCALE respectively, then the biochemical component content was retrieved by inverting the coupled polynomial expression + PROSPECT model. Results of the simulated test are promising, and when applying the algorithm to measured corn canopy multi-angle spectra, we also get relatively accurate chlorophyll content. It shows that the polynomial analysis provides a new method to get biochemical component content independent of any specific canopy model.

  14. Integrating Carbon Nanotubes into Microfluidic Chip for Separating Biochemical Compounds

    DEFF Research Database (Denmark)

    Chen, Miaoxiang Max; Mogensen, Klaus Bo; Bøggild, Peter;

    2012-01-01

    We present a new type of device to separate biochemical compounds wherein carbon nanotubes (CNTs) are integrated as chromatographic stationary phase. The CNTs were directly grown on the bottom of microfluidic channels on Si/SiO2 substrates by chemical vapor deposition (CVD). Acetylene was used as...

  15. Saliva as research material: Biochemical, physicochemical and practical aspects

    NARCIS (Netherlands)

    Schipper, R.G.; Silletti, E.; Vingerhoeds, M.H.

    2007-01-01

    Whole saliva is a complex mixture of proteins and other molecules which originate from several sources. The biochemical and physicochemical properties of saliva contribute to the numerous functions of saliva in, e.g., speech, maintaining oral and general health, and food processing. Interest in sali

  16. 40 CFR 798.5195 - Mouse biochemical specific locus test.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Mouse biochemical specific locus test. 798.5195 Section 798.5195 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Genetic Toxicity § 798.5195...

  17. Biochemical correlates in an animal model of depression

    International Nuclear Information System (INIS)

    A valid animal model of depression was used to explore specific adrenergic receptor differences between rats exhibiting aberrant behavior and control groups. Preliminary experiments revealed a distinct upregulation of hippocampal beta-receptors (as compared to other brain regions) in those animals acquiring a response deficit as a result of exposure to inescapable footshock. Concurrent studies using standard receptor binding techniques showed no large changes in the density of alpha-adrenergic, serotonergic, or dopaminergic receptor densities. This led to the hypothesis that the hippocampal beta-receptor in responses deficient animals could be correlated with the behavioral changes seen after exposure to the aversive stimulus. Normalization of the behavior through the administration of antidepressants could be expected to reverse the biochemical changes if these are related to the mechanism of action of antidepressant drugs. This study makes three important points: (1) there is a relevant biochemical change in the hippocampus of response deficient rats which occurs in parallel to a well-defined behavior, (2) the biochemical and behavioral changes are normalized by antidepressant treatments exhibiting both serotonergic and adrenergic mechanisms of action, and (3) the mode of action of antidepressants in this model is probably a combination of serotonergic and adrenergic influences modulating the hippocampal beta-receptor. These results are discussed in relation to anatomical and biochemical aspects of antidepressant action

  18. Biochemical Characterization of Prion Strains in Bank Voles

    Directory of Open Access Journals (Sweden)

    Romolo Nonno

    2013-07-01

    Full Text Available Prions exist as different strains exhibiting distinct disease phenotypes. Currently, the identification of prion strains is still based on biological strain typing in rodents. However, it has been shown that prion strains may be associated with distinct PrPSc biochemical types. Taking advantage of the availability of several prion strains adapted to a novel rodent model, the bank vole, we investigated if any prion strain was actually associated with distinctive PrPSc biochemical characteristics and if it was possible to univocally identify strains through PrPSc biochemical phenotypes. We selected six different vole-adapted strains (three human-derived and three animal-derived and analyzed PrPSc from individual voles by epitope mapping of protease resistant core of PrPSc (PrPres and by conformational stability and solubility assay. Overall, we discriminated five out of six prion strains, while two different scrapie strains showed identical PrPSc types. Our results suggest that the biochemical strain typing approach here proposed was highly discriminative, although by itself it did not allow us to identify all prion strains analyzed.

  19. Biochemical tests for diagnosis of phaeochromocytoma: urinary versus plasma determinations.

    OpenAIRE

    Plouin, P F; Duclos, J M; Menard, J; Comoy, E; Bohuon, C; Alexandre, J M

    1981-01-01

    Fifteen patients with hypertension due to phaeochromocytoma and 35 controls with essential hypertension were studied to assess the diagnostic value of urinary and plasma biochemical determinations in phaeochromocytoma. In every case of phaeochromocytoma the urinary concentration of vanillylmandelate, metanephrines, or adrenaline plus noradrenaline was diagnostic of the disease irrespective of whether the patient was normotensive or hypertensive at the time. Plasma determinations of adrenaline...

  20. Has Human Evolution Stopped?

    Directory of Open Access Journals (Sweden)

    Alan R. Templeton

    2010-07-01

    Full Text Available It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  1. Thermodynamically consistent Bayesian analysis of closed biochemical reaction systems

    Directory of Open Access Journals (Sweden)

    Goutsias John

    2010-11-01

    Full Text Available Abstract Background Estimating the rate constants of a biochemical reaction system with known stoichiometry from noisy time series measurements of molecular concentrations is an important step for building predictive models of cellular function. Inference techniques currently available in the literature may produce rate constant values that defy necessary constraints imposed by the fundamental laws of thermodynamics. As a result, these techniques may lead to biochemical reaction systems whose concentration dynamics could not possibly occur in nature. Therefore, development of a thermodynamically consistent approach for estimating the rate constants of a biochemical reaction system is highly desirable. Results We introduce a Bayesian analysis approach for computing thermodynamically consistent estimates of the rate constants of a closed biochemical reaction system with known stoichiometry given experimental data. Our method employs an appropriately designed prior probability density function that effectively integrates fundamental biophysical and thermodynamic knowledge into the inference problem. Moreover, it takes into account experimental strategies for collecting informative observations of molecular concentrations through perturbations. The proposed method employs a maximization-expectation-maximization algorithm that provides thermodynamically feasible estimates of the rate constant values and computes appropriate measures of estimation accuracy. We demonstrate various aspects of the proposed method on synthetic data obtained by simulating a subset of a well-known model of the EGF/ERK signaling pathway, and examine its robustness under conditions that violate key assumptions. Software, coded in MATLAB®, which implements all Bayesian analysis techniques discussed in this paper, is available free of charge at http://www.cis.jhu.edu/~goutsias/CSS%20lab/software.html. Conclusions Our approach provides an attractive statistical methodology for

  2. Industrial dust sulphate and its effects on biochemical and morphological characteristics of Morus (Morus alba) plant in NCR Delhi.

    Science.gov (United States)

    Gupta, Gyan Prakash; Singh, Sudha; Kumar, Bablu; Kulshrestha, U C

    2015-03-01

    Abundance of CaCO3 rich soil dust is a typical feature of atmospheric environment in the Indian region. During prevailing dry weather conditions, dustfall is deposited onto the foliar surfaces of plant affecting their morphology, stomata and the levels of biochemical constituents. This study reports the chemical characteristics of dustfall, its effect on foliar morphology and biochemical constituents of a medicinal plant (Morus alba) at two sites which are differentiated on the basis of landuse pattern, viz., (i) residential, Jawaharlal Nehru University (JNU), and (ii) industrial, Sahibabad (SB), located in the National Capital Region (NCR) of Delhi. Dustfall was characterized for major anions (F(-), Cl(-), NO3 (-) and SO4 (--)) and cations (Na(+), NH4 (+), K(+), Mg(++) and Ca(++)). Biochemical parameters such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, proline and ascorbic acid were determined in foliar samples. The results showed that the dustfall fluxes of all the major ions were found to be higher at the industrial site (SB) as compared to the residential site (JNU). Foliar analysis revealed that the levels of biochemical parameters were more affected at SB site due to higher levels of dust SO4 (--) contributed by various anthropogenic sources resulting in more stressful conditions affecting the biochemistry of the plant. The possible entry pathways for dust SO4 (--) into foliar cells are also discussed in the paper. It was noticed that the deposition of urban dust was responsible for the damage of trichome, epidermis, cuticle and stomatal guard cells significantly affecting foliar morphology. SB exhibited more damage to these morphological parts suggesting that industrial dust is harmful to the plants.

  3. Spectrophotometric study of Co(II, Ni(II, Cu(II, Zn(II, Pd(II and Hg(II complexes with isatin- β-thiosemicarbazone

    Directory of Open Access Journals (Sweden)

    SANDRA S. KONSTANTINOVIC

    2007-10-01

    Full Text Available The composition and stability of the complexes of isatin-b-thiosemicarba­zone with Co(II, Ni(II, Cu(II, Zn(II, Pd(II and Hg(II have been investigated us­ing spectrophotometric method at 30 °C and constant ionic strength of 0.1 mol dm-3 (KNO3 in 70 % ethanol. Experimental results indicate the formation of MeL and MeL2 complexes for Ni(II and Co(II, and MeL for Cu(II, Zn(II, Pd(II and Hg(II complexes, whose stability constants, bn, have been calculated using a com­puteri­zed iterative method of successive approximation.

  4. INVESTIGATIONS ON BIOCHEMICAL PURIFICATION OF GROUND WATER FROM HYDROGEN SULFIDE

    Directory of Open Access Journals (Sweden)

    Yu. P. Sedlukho

    2015-01-01

    Full Text Available The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa. The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality

  5. The Role of Hydrogen Sulfide in Evolution and the Evolution of Hydrogen Sulfide in Metabolism and Signaling.

    Science.gov (United States)

    Olson, Kenneth R; Straub, Karl D

    2016-01-01

    The chemical versatility of sulfur and its abundance in the prebiotic Earth as reduced sulfide (H2S) implicate this molecule in the origin of life 3.8 billion years ago and also as a major source of energy in the first seven-eighths of evolution. The tremendous increase in ambient oxygen ∼ 600 million years ago brought an end to H2S as an energy source, and H2S-dependent animals either became extinct, retreated to isolated sulfide niches, or adapted. The first 3 billion years of molecular tinkering were not lost, however, and much of this biochemical armamentarium easily adapted to an oxic environment where it contributes to metabolism and signaling even in humans. This review examines the role of H2S in evolution and the evolution of H2S metabolism and signaling. PMID:26674552

  6. Functional evolution of quantum cylindrical waves

    CERN Document Server

    Cho, D H J; Cho, Demian H.J.; Varadarajan, Madhavan

    2006-01-01

    Kucha{\\v{r}} showed that the quantum dynamics of (1 polarization) cylindrical wave solutions to vacuum general relativity is determined by that of a free axially-symmetric scalar field along arbitrary axially-symmetric foliations of a fixed flat 2+1 dimensional spacetime. We investigate if such a dynamics can be defined {\\em unitarily} within the standard Fock space quantization of the scalar field. Evolution between two arbitrary slices of an arbitrary foliation of the flat spacetime can be built out of a restricted class of evolutions (and their inverses). The restricted evolution is from an initial flat slice to an arbitrary (in general, curved) slice of the flat spacetime and can be decomposed into (i) `time' evolution in which the spatial Minkowskian coordinates serve as spatial coordinates on the initial and the final slice, followed by (ii) the action of a spatial diffeomorphism of the final slice on the data obtained from (i). We show that although the functional evolution of (i) is unitarily implemen...

  7. Hydrogen evolution catalyzed by cobaloximes.

    Science.gov (United States)

    Dempsey, Jillian L; Brunschwig, Bruce S; Winkler, Jay R; Gray, Harry B

    2009-12-21

    Natural photosynthesis uses sunlight to drive the conversion of energy-poor molecules (H(2)O, CO(2)) to energy-rich ones (O(2), (CH(2)O)(n)). Scientists are working hard to develop efficient artificial photosynthetic systems toward the "Holy Grail" of solar-driven water splitting. High on the list of challenges is the discovery of molecules that efficiently catalyze the reduction of protons to H(2). In this Account, we report on one promising class of molecules: cobalt complexes with diglyoxime ligands (cobaloximes). Chemical, electrochemical, and photochemical methods all have been utilized to explore proton reduction catalysis by cobaloxime complexes. Reduction of a Co(II)-diglyoxime generates a Co(I) species that reacts with a proton source to produce a Co(III)-hydride. Then, in a homolytic pathway, two Co(III)-hydrides react in a bimolecular step to eliminate H(2). Alternatively, in a heterolytic pathway, protonation of the Co(III)-hydride produces H(2) and Co(III). A thermodynamic analysis of H(2) evolution pathways sheds new light on the barriers and driving forces of the elementary reaction steps involved in proton reduction by Co(I)-diglyoximes. In combination with experimental results, this analysis shows that the barriers to H(2) evolution along the heterolytic pathway are, in most cases, substantially greater than those of the homolytic route. In particular, a formidable barrier is associated with Co(III)-diglyoxime formation along the heterolytic pathway. Our investigations of cobaloxime-catalyzed H(2) evolution, coupled with the thermodynamic preference for a homolytic route, suggest that the rate-limiting step is associated with formation of the hydride. An efficient water splitting device may require the tethering of catalysts to an electrode surface in a fashion that does not inhibit association of Co(III)-hydrides. PMID:19928840

  8. Groupware requirements evolution patterns

    OpenAIRE

    Pumareja, Dulce Trinidad

    2013-01-01

    Requirements evolution is a generally known problem in software development. Requirements are known to change all throughout a system's lifecycle. Nevertheless, requirements evolution is a poorly understood phenomenon. Most studies on requirements evolution focus on changes to written specifications and on software architecture and design. Usually, the focus is when the software is under development. Little is known about how requirements evolve when software is put into use. Groupware is an ...

  9. Creationism and evolution

    OpenAIRE

    Quintelier, Katinka; Blancke, Stefaan

    2009-01-01

    In Tower of Babel, Robert Pennock wrote that “defenders of evolution would help their case immeasurably if they would reassure their audience that morality, purpose, and meaning are not lost by accepting the truth of evolution.” We first consider the thesis that the creationists’ movement exploits moral concerns to spread its ideas against the theory of evolution. We analyze their arguments and possible reasons why they are easily accepted. Creationists usually empl...

  10. Software architecture evolution

    DEFF Research Database (Denmark)

    Barais, Olivier; Le Meur, Anne-Francoise; Duchien, Laurence;

    2008-01-01

    Software architectures must frequently evolve to cope with changing requirements, and this evolution often implies integrating new concerns. Unfortunately, when the new concerns are crosscutting, existing architecture description languages provide little or no support for this kind of evolution...... one particular framework named Tran SAT, which addresses the above problems of software architecture evolution. Tran SAT provides a new element in the software architecture descriptions language, called an architectural aspect, for describing new concerns and their integration into an existing...

  11. Oxygen evolution reaction catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  12. Evolution of Bioreactors for Extracorporeal Liver Support

    Directory of Open Access Journals (Sweden)

    Vilkova Е.V.

    2014-03-01

    Full Text Available The development of effective extracorporeal liver support systems in acute and chronic hepatic failure for transplantology purposes and in toxic injuries is a promising direction in modern biomedical studies. Widely used techniques are based on physicochemical interactions of biological molecules, and able to perform a detoxification function only (hemodialysis, hemofiltration, hemodiafiltration, sorption, albumin dialysis, plasmapheresis. However, support systems combining both blood/plasma perfusion and cellular technologies to maintain metabolic, synthetic and regulatory hepatic functions — “artificial liver” systems — are being extensively developed in recent decades. The review describes the main types of cell lines cultured to occupy bioreactors, various technological concepts for bioreactor design (dynamic, static, scaffold-carriers as part of bioreactors (structure, biochemical composition. The study gives metabolic characteristics of a cellular component of “bioartificial liver”: nourishment, oxygen saturation. Various types of existing extracorporeal support systems, their evolution, and preclinical and clinical test results are presented.

  13. Synthetic Evolution of Metabolic Productivity Using Biosensors.

    Science.gov (United States)

    Williams, Thomas C; Pretorius, Isak S; Paulsen, Ian T

    2016-05-01

    Synthetic biology has progressed to the point where genes that encode whole metabolic pathways and even genomes can be manufactured and brought to life. This impressive ability to synthesise and assemble DNA is not yet matched by an ability to predictively engineer biology. These difficulties exist because biological systems are often overwhelmingly complex, having evolved to facilitate growth and survival rather than specific engineering objectives such as the optimisation of biochemical production. A promising and revolutionary solution to this problem is to harness the process of evolution to create microbial strains with desired properties. The tools of systems biology can then be applied to understand the principles of biological design, bringing synthetic biology closer to becoming a predictive engineering discipline. PMID:26948437

  14. High dose-rate brachytherapy boost for intermediate risk prostate cancer: Long-term outcomes of two different treatment schedules and early biochemical predictors of success

    International Nuclear Information System (INIS)

    Background and purpose: To report long-term cancer control rates following high dose-rate (HDR) brachytherapy boost for intermediate risk prostate cancer and explore early biochemical predictors of success. Material and methods: Results of two sequential phase II trials are updated and compared: (1) Single 15 Gy HDR-boost followed by external beam radiotherapy (EBRT) 37.5 Gy/15fractions, (2) Two HDR fractions of 10 Gy followed by EBRT 45 Gy/25fractions. Patients were followed prospectively for clinical and biochemical outcomes. Nadir PSA (nPSA) and PSA at 3-years were analyzed as continuous variables, and ROC analysis was used to identify the optimal cutoff values. Kaplan–Meier bDFS curves were generated and the log-rank test used to compare different groups Results: 183 patients were accrued; 123 to the single fraction trial and 60 to the standard fractionation trial, with a median follow-up of 74 months and 99 months, respectively. The 5-year biochemical relapse-free survival was 97.4% and 92.7%, respectively (p = 0.995). Median nPSA was 0.08 ng/ml. Failure to achieve a nPSA <0.4 ng/ml was associated with a significantly higher rate of biochemical relapse (5-year bDFS: 100% vs. 72%; p < 0.0001). Conclusion: HDR boost with single fraction 15 Gy provides durable long-term biochemical disease-free survival. PSA nadir <0.4 ng/ml is associated with very low risk of biochemical failure

  15. Museums teach evolution.

    Science.gov (United States)

    Diamond, Judy; Evans, E Margaret

    2007-06-01

    Natural history museums play a significant role in educating the general public about evolution. This article describes Explore Evolution, one of the largest evolution education projects funded by the National Science Foundation. A group of regional museums from the Midwestern United States worked with leading evolutionary scientists to create multiple permanent exhibit galleries and a curriculum book for youth. This program invites the public to experience current evolutionary research on organisms that range in size from HIV to whales. Learning research is being conducted on museum visitors to understand how they reason about evolution and to determine what influences the process of conceptual change.

  16. Quininium tetrachloridozinc(II

    Directory of Open Access Journals (Sweden)

    Li-Zhuang Chen

    2009-10-01

    Full Text Available The asymmetric unit of the title compound {systematic name: 2-[hydroxy(6-methoxyquinolin-1-ium-4-ylmethyl]-8-vinylquinuclidin-1-ium tetrachloridozinc(II}, (C20H26N2O2[ZnCl4], consists of a double protonated quininium cation and a tetrachloridozinc(II anion. The ZnII ion is in a slightly distorted tetrahedral coordination environment. The crystal structure is stabilized by intermolecular N—H...Cl and O—H...Cl hydrogen bonds.

  17. Biochemical aspects of overtraining in endurance sports : the metabolism alteration process syndrome.

    Science.gov (United States)

    Petibois, Cyril; Cazorla, Georges; Poortmans, Jacques-Rémi; Déléris, Gérard

    2003-01-01

    Recent studies have shown that endurance overtraining could result from successive and cumulative alterations in metabolism, which become chronic during training. The onset of this process is a biochemical alteration in carbohydrate (saccharide) metabolism. During endurance exercises, the amount of saccharide chains from two blood glycoproteins (alpha(2)-macroglobulin and alpha(1)-acid glycoprotein) was found to have decreased, i.e. concentrations of these proteins remained unchanged but their quality changed. These saccharide chains were probably used for burning liver glycogen stores during exercise. This step was followed by alterations in lipid metabolism. The most relevant aspect of this step was that the mean chain length of blood fatty acids decreased, i.e. the same amount of fatty acids were found within the blood, but overtrained individuals presented shorter fatty acids than well-trained individuals. This suggests that alterations appeared in the liver synthesis of long-chain fatty acids or that higher peroxidation of blood lipoparticles occurred. For the final step of this overtraining process, it was found that these dysfunctions in carbohydrate/lipid metabolism led to the higher use of amino acids, which probably resulted from protein catabolism. The evolution of three protein concentrations (alpha(1)-acid glycoprotein, alpha(2)-macroglobulin and IgG(3)) correlated with this amino acid concentration increase, suggesting a specific catabolism of these proteins. At this time only, overtraining was clinically diagnosed through conventional symptoms. Therefore, this process described successive alterations in exercise metabolism that shifted from the main energetic stores of exercise (carbohydrates and lipids) towards molecular pools (proteins) normally not substantially used for the energetic supply of skeletal muscles. Now, a general biochemical model of the overtraining process may be proposed which includes most of the previously identified metabolic

  18. Reconstructed Ancestral Enzymes Impose a Fitness Cost upon Modern Bacteria Despite Exhibiting Favourable Biochemical Properties.

    Science.gov (United States)

    Hobbs, Joanne K; Prentice, Erica J; Groussin, Mathieu; Arcus, Vickery L

    2015-10-01

    Ancestral sequence reconstruction has been widely used to study historical enzyme evolution, both from biochemical and cellular perspectives. Two properties of reconstructed ancestral proteins/enzymes are commonly reported--high thermostability and high catalytic activity--compared with their contemporaries. Increased protein stability is associated with lower aggregation rates, higher soluble protein abundance and a greater capacity to evolve, and therefore, these proteins could be considered "superior" to their contemporary counterparts. In this study, we investigate the relationship between the favourable in vitro biochemical properties of reconstructed ancestral enzymes and the organismal fitness they confer in vivo. We have previously reconstructed several ancestors of the enzyme LeuB, which is essential for leucine biosynthesis. Our initial fitness experiments revealed that overexpression of ANC4, a reconstructed LeuB that exhibits high stability and activity, was only able to partially rescue the growth of a ΔleuB strain, and that a strain complemented with this enzyme was outcompeted by strains carrying one of its descendants. When we expanded our study to include five reconstructed LeuBs and one contemporary, we found that neither in vitro protein stability nor the catalytic rate was correlated with fitness. Instead, fitness showed a strong, negative correlation with estimated evolutionary age (based on phylogenetic relationships). Our findings suggest that, for reconstructed ancestral enzymes, superior in vitro properties do not translate into organismal fitness in vivo. The molecular basis of the relationship between fitness and the inferred age of ancestral LeuB enzymes is unknown, but may be related to the reconstruction process. We also hypothesise that the ancestral enzymes may be incompatible with the other, contemporary enzymes of the metabolic network. PMID:26349578

  19. Hydrosol II Project; El Proyecto Hydrosol II

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Martinez, A.

    2008-07-01

    At present energy production is based on the combustion of fossil fuels and is the main cause of greenhouse gas emissions, which is to say it is the main cause of the climate change that is affecting the planet. On a worldwide scale, the use of solar concentration systems with systems capable of dissociating water is considered, from both an energy and an economic standpoint, as the most important long-term goal in the production of solar fuels to reduce the costs of hydrogen and to ensure practically zero carbon dioxide emissions. The Hydrosol II project has the largest pilot plant of its kind, and the Hydrosol II reactors will be capable of breaking up the water molecule on the basis of thermochemical cycles at moderate temperatures. The Hydrosol II project pilot plant is now a reality, located in the SSPS heliostats field of the Almeria Solar Platform. (Author)

  20. Programmed evolution for optimization of orthogonal metabolic output in bacteria.

    Directory of Open Access Journals (Sweden)

    Todd T Eckdahl

    Full Text Available Current use of microbes for metabolic engineering suffers from loss of metabolic output due to natural selection. Rather than combat the evolution of bacterial populations, we chose to embrace what makes biological engineering unique among engineering fields - evolving materials. We harnessed bacteria to compute solutions to the biological problem of metabolic pathway optimization. Our approach is called Programmed Evolution to capture two concepts. First, a population of cells is programmed with DNA code to enable it to compute solutions to a chosen optimization problem. As analog computers, bacteria process known and unknown inputs and direct the output of their biochemical hardware. Second, the system employs the evolution of bacteria toward an optimal metabolic solution by imposing fitness defined by metabolic output. The current study is a proof-of-concept for Programmed Evolution applied to the optimization of a metabolic pathway for the conversion of caffeine to theophylline in E. coli. Introduced genotype variations included strength of the promoter and ribosome binding site, plasmid copy number, and chaperone proteins. We constructed 24 strains using all combinations of the genetic variables. We used a theophylline riboswitch and a tetracycline resistance gene to link theophylline production to fitness. After subjecting the mixed population to selection, we measured a change in the distribution of genotypes in the population and an increased conversion of caffeine to theophylline among the most fit strains, demonstrating Programmed Evolution. Programmed Evolution inverts the standard paradigm in metabolic engineering by harnessing evolution instead of fighting it. Our modular system enables researchers to program bacteria and use evolution to determine the combination of genetic control elements that optimizes catabolic or anabolic output and to maintain it in a population of cells. Programmed Evolution could be used for applications in

  1. Programmed evolution for optimization of orthogonal metabolic output in bacteria.

    Science.gov (United States)

    Eckdahl, Todd T; Campbell, A Malcolm; Heyer, Laurie J; Poet, Jeffrey L; Blauch, David N; Snyder, Nicole L; Atchley, Dustin T; Baker, Erich J; Brown, Micah; Brunner, Elizabeth C; Callen, Sean A; Campbell, Jesse S; Carr, Caleb J; Carr, David R; Chadinha, Spencer A; Chester, Grace I; Chester, Josh; Clarkson, Ben R; Cochran, Kelly E; Doherty, Shannon E; Doyle, Catherine; Dwyer, Sarah; Edlin, Linnea M; Evans, Rebecca A; Fluharty, Taylor; Frederick, Janna; Galeota-Sprung, Jonah; Gammon, Betsy L; Grieshaber, Brandon; Gronniger, Jessica; Gutteridge, Katelyn; Henningsen, Joel; Isom, Bradley; Itell, Hannah L; Keffeler, Erica C; Lantz, Andrew J; Lim, Jonathan N; McGuire, Erin P; Moore, Alexander K; Morton, Jerrad; Nakano, Meredith; Pearson, Sara A; Perkins, Virginia; Parrish, Phoebe; Pierson, Claire E; Polpityaarachchige, Sachith; Quaney, Michael J; Slattery, Abagael; Smith, Kathryn E; Spell, Jackson; Spencer, Morgan; Taye, Telavive; Trueblood, Kamay; Vrana, Caroline J; Whitesides, E Tucker

    2015-01-01

    Current use of microbes for metabolic engineering suffers from loss of metabolic output due to natural selection. Rather than combat the evolution of bacterial populations, we chose to embrace what makes biological engineering unique among engineering fields - evolving materials. We harnessed bacteria to compute solutions to the biological problem of metabolic pathway optimization. Our approach is called Programmed Evolution to capture two concepts. First, a population of cells is programmed with DNA code to enable it to compute solutions to a chosen optimization problem. As analog computers, bacteria process known and unknown inputs and direct the output of their biochemical hardware. Second, the system employs the evolution of bacteria toward an optimal metabolic solution by imposing fitness defined by metabolic output. The current study is a proof-of-concept for Programmed Evolution applied to the optimization of a metabolic pathway for the conversion of caffeine to theophylline in E. coli. Introduced genotype variations included strength of the promoter and ribosome binding site, plasmid copy number, and chaperone proteins. We constructed 24 strains using all combinations of the genetic variables. We used a theophylline riboswitch and a tetracycline resistance gene to link theophylline production to fitness. After subjecting the mixed population to selection, we measured a change in the distribution of genotypes in the population and an increased conversion of caffeine to theophylline among the most fit strains, demonstrating Programmed Evolution. Programmed Evolution inverts the standard paradigm in metabolic engineering by harnessing evolution instead of fighting it. Our modular system enables researchers to program bacteria and use evolution to determine the combination of genetic control elements that optimizes catabolic or anabolic output and to maintain it in a population of cells. Programmed Evolution could be used for applications in energy

  2. Type II universal spacetimes

    Science.gov (United States)

    Hervik, S.; Málek, T.; Pravda, V.; Pravdová, A.

    2015-12-01

    We study type II universal metrics of the Lorentzian signature. These metrics simultaneously solve vacuum field equations of all theories of gravitation with the Lagrangian being a polynomial curvature invariant constructed from the metric, the Riemann tensor and its covariant derivatives of an arbitrary order. We provide examples of type II universal metrics for all composite number dimensions. On the other hand, we have no examples for prime number dimensions and we prove the non-existence of type II universal spacetimes in five dimensions. We also present type II vacuum solutions of selected classes of gravitational theories, such as Lovelock, quadratic and L({{Riemann}}) gravities.

  3. Burkina Faso - BRIGHT II

    Data.gov (United States)

    Millenium Challenge Corporation — Millennium Challenge Corporation hired Mathematica Policy Research to conduct an independent evaluation of the BRIGHT II program. The three main research questions...

  4. Biochemical studies on Francisella tularensis RelA in (p)ppGpp biosynthesis.

    Science.gov (United States)

    Wilkinson, Rachael C; Batten, Laura E; Wells, Neil J; Oyston, Petra C F; Roach, Peter L

    2015-10-08

    The bacterial stringent response is induced by nutrient deprivation and is mediated by enzymes of the RSH (RelA/SpoT homologue; RelA, (p)ppGpp synthetase I; SpoT, (p)ppGpp synthetase II) superfamily that control concentrations of the 'alarmones' (p)ppGpp (guanosine penta- or tetra-phosphate). This regulatory pathway is present in the vast majority of pathogens and has been proposed as a potential anti-bacterial target. Current understanding of RelA-mediated responses is based on biochemical studies using Escherichia coli as a model. In comparison, the Francisella tularensis RelA sequence contains a truncated regulatory C-terminal region and an unusual synthetase motif (EXSD). Biochemical analysis of F. tularensis RelA showed the similarities and differences of this enzyme compared with the model RelA from Escherichia coli. Purification of the enzyme yielded a stable dimer capable of reaching concentrations of 10 mg/ml. In contrast with other enzymes from the RelA/SpoT homologue superfamily, activity assays with F. tularensis RelA demonstrate a high degree of specificity for GTP as a pyrophosphate acceptor, with no measurable turnover for GDP. Steady state kinetic analysis of F. tularensis RelA gave saturation activity curves that best fitted a sigmoidal function. This kinetic profile can result from allosteric regulation and further measurements with potential allosteric regulators demonstrated activation by ppGpp (5',3'-dibisphosphate guanosine) with an EC50 of 60±1.9 μM. Activation of F. tularensis RelA by stalled ribosomal complexes formed with ribosomes purified from E. coli MRE600 was observed, but interestingly, significantly weaker activation with ribosomes isolated from Francisella philomiragia.

  5. 40 CFR 158.2081 - Experimental use permit biochemical pesticides product chemistry data requirements table.

    Science.gov (United States)

    2010-07-01

    ... pesticides product chemistry data requirements table. 158.2081 Section 158.2081 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2081 Experimental use permit biochemical pesticides product chemistry data...

  6. 40 CFR 158.2084 - Experimental use permit biochemical pesticides nontarget organisms and environmental fate data...

    Science.gov (United States)

    2010-07-01

    ... pesticides nontarget organisms and environmental fate data requirements table. 158.2084 Section 158.2084 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Biochemical Pesticides § 158.2084 Experimental use permit biochemical...

  7. Bis(thiosemicarbazonato) chelates of Co(II), Ni(II), Cu(II), Pd(II) and Pt(II)

    Science.gov (United States)

    Chandra, Sulekh; Singh, R.

    1985-01-01

    Bis chelates of Co(II), Ni(II), Cu(II), Pd(II) and Pt(II) with the enolic form of diethyl ketone and methyl n-propyl thiosemicarbazones were synthesized and characterized by elemental analyses, magnetic moments, i.r. and electronic and electron spin resonance spectral studies. All the complexes were found to have the composition ML 2 [where M = Co(II), Ni(II), Cu(II), Pd(ii) and Pt(II) and L = thiosemicarbazones of diethyl ketone and methyl n-propyl ketone]. Co(II) and Cu(II) complexes are paramagnetic and may have polymeric six-coordinate octahedral and square planar geometries, respectively. The Ni(II), Pd(II) and Pt(II) complexes are diamagnetic and may have square planar geometries. Pyridine adducts (ML 2·2Py) of Ni(II) and Cu(II) complexes were also prepared and characterized.

  8. Evolution of Constructivism

    Science.gov (United States)

    Liu, Chu Chih; Chen, I Ju

    2010-01-01

    The contrast between social constructivism and cognitive constructivism are depicted in different ways in many studies. The purpose of this paper is to summarize the evolution of constructivism and put a focus on social constructivism from the perception of Vygotsky. This study provides a general idea of the evolution of constructivism for people…

  9. Evolution: Theory or Dogma?

    Science.gov (United States)

    Mayer, William V.

    In this paper the author examines the question of whether evolution is a theory or a dogma. He refutes the contention that there is a monolithic scientific conspiracy to present evolution as dogma and suggests that his own presentation might be more appropriately entitled "Creationism: Theory or Dogma." (PEB)

  10. Software evolution with XVCL

    DEFF Research Database (Denmark)

    Zhang, Weishan; Jarzabek, Stan; Zhang, Hongyu;

    2004-01-01

    This chapter introduces software evolution with XVCL (XML-based Variant Configuration Language), which is an XML-based metaprogramming technique. As the software evolves, a large number of variants may arise, especially whtn such kinds of evolutions are related to multiple platforms as shown in o...

  11. Kognition, evolution og Bibel

    DEFF Research Database (Denmark)

    Jensen, Hans Jørgen Lundager

    2012-01-01

    En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)......En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)...

  12. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  13. Framing Evolution Discussion Intellectually

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin; Buck, Gayle A.

    2011-01-01

    This study examines how a first-year biology teacher facilitates a series of whole-class discussions about evolution during the implementation of a problem-based unit. A communicative theoretical perspective is adopted wherein evolution discussions are viewed as social events that the teacher can frame intellectually (i.e., present or organize as…

  14. Evolution for Young Victorians

    Science.gov (United States)

    Lightman, Bernard

    2012-01-01

    Evolution was a difficult topic to tackle when writing books for the young in the wake of the controversies over Darwin's "Origin of Species." Authors who wrote about evolution for the young experimented with different ways of making the complex concepts of evolutionary theory accessible and less controversial. Many authors depicted presented…

  15. Introduction: Understanding Legal Evolution

    NARCIS (Netherlands)

    K. Heine (Klaus)

    2012-01-01

    markdownabstract__Abstract__ In recent years, the study of legal evolution has become more systematic, and there have emerged various approaches to the study of legal evolution. However, until now, there has been no consensus as to which of these approaches is the most appropriate for the purposes

  16. Quantifying the evolution of world trade, 1870-1949

    NARCIS (Netherlands)

    Klasing, Mariko J.; Milionis, Petros

    2014-01-01

    The typical narrative regarding the evolution of world trade prior to World War II refers to a secular rise starting around 1870 and a subsequent collapse beginning in 1914. This narrative, however, is based on measures of trade openness that do not fully take into account purchasing power differenc

  17. Biochemical functionalization of peptide nanotubes with phage displayed peptides

    Science.gov (United States)

    Swaminathan, Swathi; Cui, Yue

    2016-09-01

    The development of a general approach for the biochemical functionalization of peptide nanotubes (PNTs) could open up existing opportunities in both fundamental studies as well as a variety of applications. PNTs are spontaneously assembled organic nanostructures made from peptides. Phage display has emerged as a powerful approach for identifying selective peptide binding motifs. Here, we demonstrate for the first time the biochemical functionalization of PNTs via peptides identified from a phage display peptide library. The phage-displayed peptides are shown to recognize PNTs. These advances further allow for the development of bifunctional peptides for the capture of bacteria and the self-assembly of silver particles onto PNTs. We anticipate that these results could provide significant opportunities for using PNTs in both fundamental studies and practical applications, including sensors and biosensors nanoelectronics, energy storage devices, drug delivery, and tissue engineering.

  18. Polyamines as salinity biochemical marker in callus of eucalyptus urograndis

    Directory of Open Access Journals (Sweden)

    Giuseppina Lima Pace Pereira

    2003-01-01

    Full Text Available Biochemical markers have been used for the analysis of plant cells submitted to several types of stress, among them salinity. This work aimed at analyzing the effect of saline stress in callus of Eucalyptus urograndis on polyamine contents. Explants (hypocotyls obtained from seeds were inoculated in callus inductive medium, submitted to different levels of NaCl and analyzed at 10, 20 and 30 days after the inoculation. The free polyamines were extracted, isolated and quantified using TLC (Thin-Layer Chromatography. Putrescine content was higher and a fall in the spermidine content was observed in callus submitted to salinity condition. The results showed that polyamine accumulation is related to NaCl exposure in callus of Eucalyptus urograndis. The decrease in spermine content could be used as a biochemical marker for Eucalyptus callus subjected to salinity.

  19. The application of information theory to biochemical signaling systems.

    Science.gov (United States)

    Rhee, Alex; Cheong, Raymond; Levchenko, Andre

    2012-08-01

    Cell signaling can be thought of fundamentally as an information transmission problem in which chemical messengers relay information about the external environment to the decision centers within a cell. Due to the biochemical nature of cellular signal transduction networks, molecular noise will inevitably limit the fidelity of any messages received and processed by a cell's signal transduction networks, leaving it with an imperfect impression of its environment. Fortunately, Shannon's information theory provides a mathematical framework independent of network complexity that can quantify the amount of information that can be transmitted despite biochemical noise. In particular, the channel capacity can be used to measure the maximum number of stimuli a cell can distinguish based upon the noisy responses of its signaling systems. Here, we provide a primer for quantitative biologists that covers fundamental concepts of information theory, highlights several key considerations when experimentally measuring channel capacity, and describes successful examples of the application of information theoretic analysis to biological signaling.

  20. Adult amphibian epidermal proteins: biochemical characterization and developmental appearance.

    Science.gov (United States)

    Reeves, O R

    1975-08-01

    The keratin-like proteins (KLPs) from the epidermis of adult frogs of the species Xenopus laevis have been isolated and biochemically characterized by means of polyacrylamide gel electrophoresis, amino acid analysis, tryptic peptide mapping, amino-terminal end-group analysis and isoelectric focusing. One particular protein fraction of rather unusual amino acid composition found only in epidermal tissue was isolated in quantity by preparative gel electrophoresis and monospecific antibodies prepared against it. Using this anti-KLP antibody preparation it was possible to show that at least one kine of keratin-like protein characteristic of the adult epidermis first appears within the larval epidermis during metamorphosis. This is the first reported biochemical characterization of a tissue-specific protien from adult amphibian skin.

  1. Development of a biochemical switching device: mathematical model.

    Science.gov (United States)

    Okamoto, M

    1990-01-01

    There are many examples of enzymes that share substrates or cofactors in a cyclic manner. Techniques have been developed that use cyclic enzyme systems to assay quantitatively small amounts of biochemical substances (cofactor, substrate), however, only a few studies of the control of these systems have been published. The author previously showed with computer simulations that cyclic enzyme systems have the reliability of ON-OFF types of operation (McCulloch-Pitts' neuronic equation) and the applicability for a switching circuit in a biocomputer. The switching time was inevitably determined in accordance with the difference in amount between two inputs of the system. A unique switching mechanism of cyclic enzyme systems (basic switching element) and the effects of excitatory stimuli on switching properties of the integrated biochemical switching system are demonstrated. PMID:2082931

  2. Electrolyte-Gated Graphene Ambipolar Frequency Multipliers for Biochemical Sensing.

    Science.gov (United States)

    Fu, Wangyang; Feng, Lingyan; Mayer, Dirk; Panaitov, Gregory; Kireev, Dmitry; Offenhäusser, Andreas; Krause, Hans-Joachim

    2016-04-13

    In this Letter, the ambipolar properties of an electrolyte-gated graphene field-effect transistor (GFET) have been explored to fabricate frequency-doubling biochemical sensor devices. By biasing the ambipolar GFETs in a common-source configuration, an input sinusoidal voltage at frequency f applied to the electrolyte gate can be rectified to a sinusoidal wave at frequency 2f at the drain electrode. The extraordinary high carrier mobility of graphene and the strong electrolyte gate coupling provide the graphene ambipolar frequency doubler an unprecedented unity gain, as well as a detection limit of ∼4 pM for 11-mer single strand DNA molecules in 1 mM PBS buffer solution. Combined with an improved drift characteristics and an enhanced low-frequency 1/f noise performance by sampling at doubled frequency, this good detection limit suggests the graphene ambipolar frequency doubler a highly promising biochemical sensing platform. PMID:26928906

  3. Biochemical functionalization of peptide nanotubes with phage displayed peptides.

    Science.gov (United States)

    Swaminathan, Swathi; Cui, Yue

    2016-09-01

    The development of a general approach for the biochemical functionalization of peptide nanotubes (PNTs) could open up existing opportunities in both fundamental studies as well as a variety of applications. PNTs are spontaneously assembled organic nanostructures made from peptides. Phage display has emerged as a powerful approach for identifying selective peptide binding motifs. Here, we demonstrate for the first time the biochemical functionalization of PNTs via peptides identified from a phage display peptide library. The phage-displayed peptides are shown to recognize PNTs. These advances further allow for the development of bifunctional peptides for the capture of bacteria and the self-assembly of silver particles onto PNTs. We anticipate that these results could provide significant opportunities for using PNTs in both fundamental studies and practical applications, including sensors and biosensors nanoelectronics, energy storage devices, drug delivery, and tissue engineering. PMID:27479451

  4. The Metabolic Syndrome and Biochemical Recurrence following Radical Prostatectomy

    Directory of Open Access Journals (Sweden)

    Jennifer M. Post

    2011-01-01

    Full Text Available Metabolic syndrome refers to a set of conditions that increases the risk of cardiovascular disease and has been associated with an increased risk of prostate cancer, particularly among African American men. This study aimed to estimate the association of metabolic syndrome with biochemical recurrence (BCR in a racially diverse population. Among 383 radical prostatectomy patients, 67 patients had documented biochemical recurrence. Hypertension was significantly, positively associated with the rate of BCR (hazard ratio (HR = 2.1; 95%  CI = 1.1, 3.8. There were distinct racial differences in the prevalence of individual metabolic syndrome components; however, the observed associations with BCR did not differ appreciably by race. We conclude that hypertension may contribute to a poorer prognosis in surgically treated prostate cancer patients. Our findings suggest that targeting components of the metabolic syndrome which are potentially modifiable through lifestyle interventions may be a viable strategy to reduce risk of BCR in prostate cancer.

  5. BIOCHEMICAL PROCESSES IN CHERNOZEM SOIL UNDER DIFFERENT FERTILIZATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Ecaterina Emnova

    2012-06-01

    Full Text Available The paper deals with the evaluation of the intensity of certain soil biochemical processes (e.g. soil organic C mineralization at Organic and mixed Mineral+Organic fertilization of typical chernozem in crop rotation dynamics (for 6 years by use of eco-physiological indicators of biological soil quality: microbial biomass carbon, basal soil respiration, as well as, microbial and metabolic quotients. Soil sampling was performed from a long-term field crop experiment, which has been established in 1971 at the Balti steppe (Northern Moldova. The crop types had a more considerable impact on the soil microbial biomass accumulation and community biochemical activity compared to long-term Organic or mixed Mineral + Organic fertilizers amendments. The Org fertilization system doesn’t make it possible to avoid the loss of organic C in arable typical chernozem. The organic fertilizer (cattle manure is able to mitigate the negative consequences of long-term mineral fertilization.

  6. The free energy cost of accurate biochemical oscillations

    CERN Document Server

    Cao, Yuansheng; Ouyang, Qi; Tu, Yuhai

    2015-01-01

    Oscillation is an important cellular process that regulates timing of different vital life cycles. However, in the noisy cellular environment, oscillations can be highly inaccurate due to phase fluctuations. It remains poorly understood how biochemical circuits suppress phase fluctuations and what is the incurred thermodynamic cost. Here, we study four different types of biochemical oscillations representing three basic oscillation motifs shared by all known oscillatory systems. We find that the phase diffusion constant follows the same inverse dependence on the free energy dissipation per period for all systems studied. This relationship between the phase diffusion and energy dissipation is shown analytically in a model of noisy oscillation. Microscopically, we find that the oscillation is driven by multiple irreversible cycles that hydrolyze the fuel molecules such as ATP; the number of phase coherent periods is proportional to the free energy consumed per period. Experimental evidence in support of this un...

  7. How Can Evolution Learn?

    Science.gov (United States)

    Watson, Richard A; Szathmáry, Eörs

    2016-02-01

    The theory of evolution links random variation and selection to incremental adaptation. In a different intellectual domain, learning theory links incremental adaptation (e.g., from positive and/or negative reinforcement) to intelligent behaviour. Specifically, learning theory explains how incremental adaptation can acquire knowledge from past experience and use it to direct future behaviours toward favourable outcomes. Until recently such cognitive learning seemed irrelevant to the 'uninformed' process of evolution. In our opinion, however, new results formally linking evolutionary processes to the principles of learning might provide solutions to several evolutionary puzzles - the evolution of evolvability, the evolution of ecological organisation, and evolutionary transitions in individuality. If so, the ability for evolution to learn might explain how it produces such apparently intelligent designs. PMID:26705684

  8. How Can Evolution Learn?

    Science.gov (United States)

    Watson, Richard A; Szathmáry, Eörs

    2016-02-01

    The theory of evolution links random variation and selection to incremental adaptation. In a different intellectual domain, learning theory links incremental adaptation (e.g., from positive and/or negative reinforcement) to intelligent behaviour. Specifically, learning theory explains how incremental adaptation can acquire knowledge from past experience and use it to direct future behaviours toward favourable outcomes. Until recently such cognitive learning seemed irrelevant to the 'uninformed' process of evolution. In our opinion, however, new results formally linking evolutionary processes to the principles of learning might provide solutions to several evolutionary puzzles - the evolution of evolvability, the evolution of ecological organisation, and evolutionary transitions in individuality. If so, the ability for evolution to learn might explain how it produces such apparently intelligent designs.

  9. Chemical evolution of galaxies

    CERN Document Server

    Matteucci, Francesca

    2012-01-01

    The term “chemical evolution of galaxies” refers to the evolution of abundances of chemical species in galaxies, which is due to nuclear processes occurring in stars and to gas flows into and out of galaxies. This book deals with the chemical evolution of galaxies of all morphological types (ellipticals, spirals and irregulars) and stresses the importance of the star formation histories in determining the properties of stellar populations in different galaxies. The topic is approached in a didactical and logical manner via galaxy evolution models which are compared with observational results obtained in the last two decades: The reader is given an introduction to the concept of chemical abundances and learns about the main stellar populations in our Galaxy as well as about the classification of galaxy types and their main observables. In the core of the book, the construction and solution of chemical evolution models are discussed in detail, followed by descriptions and interpretations of observations of ...

  10. Basilea II: panacea o opportunità mancata? (Basel II: Panacea or a Missed Opportunity?

    Directory of Open Access Journals (Sweden)

    Maximilian J.B. Hall

    2004-12-01

    Full Text Available At end-June 2004, the Basel Committee on Banking Supervision finally issued the "New Capital Accord" ("Basel II", following endorsement by G10 bank supervisors. The Accord replaces the original accord agreed in July 1988 and implemented by most major international banks since 1993. Publication followed years of exhausting work by the Committee to improve upon the original in the light of market developments, advances in risk management and revealed deficiencies in the operation of the current scheme. This article traces the evolution of Basel II, focusing on the post-2000 period. The impact of the three rounds of consultation on the final shape of the Accord is explored, as is the role played by the Quantitative Impact Studies (particularly, "QIS3". Finally, Basel II is assessed from a "cost-benefit" standpoint, and outstanding concerns are identified.

  11. Accelerated maximum likelihood parameter estimation for stochastic biochemical systems

    Directory of Open Access Journals (Sweden)

    Daigle Bernie J

    2012-05-01

    Full Text Available Abstract Background A prerequisite for the mechanistic simulation of a biochemical system is detailed knowledge of its kinetic parameters. Despite recent experimental advances, the estimation of unknown parameter values from observed data is still a bottleneck for obtaining accurate simulation results. Many methods exist for parameter estimation in deterministic biochemical systems; methods for discrete stochastic systems are less well developed. Given the probabilistic nature of stochastic biochemical models, a natural approach is to choose parameter values that maximize the probability of the observed data with respect to the unknown parameters, a.k.a. the maximum likelihood parameter estimates (MLEs. MLE computation for all but the simplest models requires the simulation of many system trajectories that are consistent with experimental data. For models with unknown parameters, this presents a computational challenge, as the generation of consistent trajectories can be an extremely rare occurrence. Results We have developed Monte Carlo Expectation-Maximization with Modified Cross-Entropy Method (MCEM2: an accelerated method for calculating MLEs that combines advances in rare event simulation with a computationally efficient version of the Monte Carlo expectation-maximization (MCEM algorithm. Our method requires no prior knowledge regarding parameter values, and it automatically provides a multivariate parameter uncertainty estimate. We applied the method to five stochastic systems of increasing complexity, progressing from an analytically tractable pure-birth model to a computationally demanding model of yeast-polarization. Our results demonstrate that MCEM2 substantially accelerates MLE computation on all tested models when compared to a stand-alone version of MCEM. Additionally, we show how our method identifies parameter values for certain classes of models more accurately than two recently proposed computationally efficient methods

  12. Biochemical and antigenic properties of Streptococcus bovis isolated from pigeons.

    OpenAIRE

    De Herdt, P; Haesebrouck, F; DEVRIESE, L.A.; Ducatelle, R.

    1992-01-01

    Biochemical and serological properties of 60 strains of Streptococcus bovis isolated from healthy pigeons and from pigeons that died from S. bovis septicemia were determined. On the basis of the hemolysis of bovine erythrocytes, the production of polysaccharides on saccharose-containing media, and the fermentation of mannitol, inulin, trehalose, and L-arabinose, the isolates were classified in five biotypes and two subbiotypes. Slide agglutination and microagglutination tests using monospecif...

  13. Morphologic and biochemical studies of canine mucopolysaccharidosis I.

    OpenAIRE

    Shull, R M; Helman, R. G.; Spellacy, E.; Constantopoulos, G.; Munger, R. J.; Neufeld, E F

    1984-01-01

    This report presents the necropsy and biochemical findings on the first dog to die with alpha-L-iduronidase deficiency (mucopolysaccharidosis I, MPS I). Gross pathologic features, light- and electron-microscopic findings, and tissue enzyme, glycosaminoglycan (GAG), and sphingolipid levels are compared with the human disease counterpart and the previously described feline model. Results lend further support for the similarities of the canine disease and human MPS I.

  14. Biochemical Analyses of Sorghum Varieties Reveal Differential Responses to Drought

    OpenAIRE

    Chukwuma C Ogbaga; Piotr Stepien; Dyson, Beth C.; Nicholas J W Rattray; Ellis, David I.; Royston Goodacre; Johnson, Giles N.

    2016-01-01

    We have examined the biochemical responses of two sorghum cultivars of differing drought tolerance, Samsorg 17 (more drought tolerant) and Samsorg 40 (less drought tolerant), to sustained drought. Plants were exposed to different degrees of drought and then maintained at that level for five days. Responses were examined in terms of metabolic changes and the expression of drought induced proteins - Heat Shock Proteins (HSPs) and dehydrins (DHNs). Generalised phenotypic changes were studied usi...

  15. Molecular and biochemical studies on bovine ephemeral fever

    Directory of Open Access Journals (Sweden)

    Nahed S. Thabet; Emad W. Ghazy; Mohamed A. Nayel; Mohamed Abo-Elkhair

    2011-05-01

    Full Text Available Bovine ephemeral fever (BEF in cattle has been reported to be associated with a range of biochemical changes which are similar to those seen in milk fever. This study aimed to clarify the biochemical alterations that associate infection of cattle with BEF with special references to the mechanisms involved in the development of hypocalcemia. The study was conducted on 30 cases of cattle infected with BEF based on the characteristic clinical signs which were confirmed by isolation of virus and RT-PCR. Another 6 healthy cows were used in the study as control. The evaluated parameters included biochemical variables such as serum values of total protein (TP, albumin (Alb, glucose (Glu, total calcium (tCa, ionized calcium (iCa, inorganic phosphorus (P, magnesium (Mg, sodium (Na, potassium (K, chloride (Cl, creatinine (Cr, blood urea nitrogen (BUN and serum activity of alkaline phosphatase (ALP. Hormonal profile included parathyroid hormone (PTH, insulin (Ins, and cortisol (Cor. The results showed that BEF-infected animals demonstrated a significant decrease (P<0.05 in serum concentrations of TP, Glo, iCa, P, Na, K, BUN and ALP while the mean values of serum levels of Glu and Cl were significantly increased (P<0.05. The mean values of serum levels of PTH were significantly decreased (P<0.05 while serum concentrations of Ins and Cor showed a significant increase. It was concluded that the clinical signs of bovine ephemeral fever are related to the hypocalcemia resulting from suppression of parathyroid hormone which seems to be mediated by respiratory alkalosis caused by the disease. This explanation needs future studies to provide a direct link between measurement of blood indicators of acid-base status, blood biochemical parameters and urine analysis. However, this work can provide a good knowledge about the pathogenesis of the disease that can lead to better management and proper treatment.

  16. Optical methods for monitoring physiological and biochemical variables

    OpenAIRE

    Crowe, John; Rea, Philip; Dr. Philip Rea

    1986-01-01

    The use of optical methods for performing non-invasive physiological and biochemical monitoring has been investigated, with particular emphasis on the application of near-infrared spectrophotocetry for following changes in the redox state of cytochrome oxidase. Initial studies of the gross optical properties of in vivo tissue were made using an image intensifier. These demonstrated that some light is transmitted through biological tissues and that such material is very hi...

  17. Virtual laboratories in (bio)chemical engineering education

    OpenAIRE

    Domingues, Lucília; Rocha, I.; Dourado, Fernando; Alves, M.M.; Ferreira, E. C.

    2010-01-01

    In the last decades, Information and Communications Technologies (ICT) have been promoting the creation and adoption of new learning and teaching styles. Virtual laboratories, by overcoming some limitations of conventional hands-on experiments, have been adopted as a complement or in substitution of laboratory sessions. This paper describes the design and implementation of two virtual labs for biochemical engineering education intended for students at the BSc degree. One of the virtua...

  18. INVESTIGATIONS ON BIOCHEMICAL PURIFICATION OF GROUND WATER FROM HYDROGEN SULFIDE

    OpenAIRE

    Yu. P. Sedlukho; Yu. O. Stankevich

    2015-01-01

    The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation....

  19. Current diagnostic guidelines for biochemical diagnosis of acromegaly.

    Science.gov (United States)

    Ferone, D; Resmini, E; Bocca, L; Giusti, M; Barreca, A; Minuto, F

    2004-12-01

    Acromegaly is a rare and chronic disease that, in the majority of cases, is due to the presence of a benign growth hormone (GH)-producing tumor of the pituitary. In the past, the diagnosis of acromegaly was established basically on physical changes, and only the patients with a severe clinical picture were brought to medical attention. The development of a radioimmunoassay for detecting GH allowed for the first time to confirm the diagnosis biochemically. Subsequently, methods for measuring insulin-like growth factor 1 (IGF-I) became available and added another important biochemical marker for the diagnosis and follow-up of these patients. Progressive improvements in assay methods have allowed for progressively better definitions of normality and, as a result, have permitted the diagnosis to be biochemically established in patients with only mild forms of the disease. Moreover, new potential markers of disease activity, such as other GH-dependent IGF system parameters, have been investigated and proposed in the diagnostic work-up and for monitoring the therapeutic outcome. Optimal assessment of disease activity, for both diagnostic and follow-up purposes, is mandatory. This subject has been strongly debated regarding proper cut-off values using highly sensitive GH assays as well as the problems linked to IGF system components measurement. Consequently, several consensus reports, as well as original studies, have been issued giving special attention to diagnostic procedures, cut-off revisions and definition of disease activity. The present review discuss principally the biochemical diagnosis of acromegaly based on these articles and on the experience collected in an endocrinological unit considered as reference center for pituitary diseases. PMID:15765030

  20. ADVANCES ON BILINEAR MODELING OF BIOCHEMICAL BATCH PROCESSES

    OpenAIRE

    GONZÁLEZ MARTÍNEZ, JOSÉ MARÍA

    2015-01-01

    [EN] This thesis is aimed to study the implications of the statistical modeling approaches proposed for the bilinear modeling of batch processes, develop new techniques to overcome some of the problems that have not been yet solved and apply them to data of biochemical processes. The study, discussion and development of the new methods revolve around the four steps of the modeling cycle, from the alignment, preprocessing and calibration of batch data to the monitoring of batches trajectories....

  1. CLINICAL AND BIOCHEMICAL CHARACTERISTICS AT THE CIRRHOSIS OF VARIOUS GENESIS

    Directory of Open Access Journals (Sweden)

    A. R. Bilalova

    2016-01-01

    Full Text Available Purpose of the study. To carry out a comparative description of the clinical and biochemical parameters at patients with cirrhosis of an alcoholic genesis (CP-HGA and cirrhosis of mixed etiologies — CP-HGM (HСV+ alcohol.Materials and methods. The study involved 62 patients with cirrhosis of different etiologies, who carries out clinical, immunogenetic and biochemical studies.Results. Patients with the 3d genotype and low viral load were registered with cirrhosis of mixed etiologies (HСV+ alcohol. At the cirrhosis Class B for Child-Pugh basic data biochemical parameters were similar in patients with CP-HGA and CP-HGM, but ALT and AST activity, which are significantly higher than observed in patients with CP-HGM. At dismissal, ALT and GGT activities were detected significantly higher in patients with CP-HGM than the CP-HGA. At the cirrhosis Class C for Child-Pugh the baseline, reflecting cholestasis — is total bilirubin, GGT and alkaline phosphatase and were detected significantly higher in the CP-HGA, than with CP-HGM significantly reduced, and thore is no differences between the groups to be discharged from the hospital, in addition to the activity of GGT, which it remained significantly higher in the CP-HGA, than with CP-HGM. Cytolytic activity of enzymes (ALT, AST during the entire period of the disease was observed significantly higher normal values and did not depend on the CP etiology.Conclusion decision. The maximum rate of change of the basic biochemical parameters is observed in patients with cirrhosis of mixed etiologies Class B for Child-Pugh and at the cirrhosis of an alcoholic genesis — in patients with cirrhosis Class C.

  2. Novel Biochemical Markers of Psychosocial Stress in Women

    OpenAIRE

    Marie Asberg; Ake Nygren; Rosario Leopardi; Gunnar Rylander; Ulla Peterson; Lukas Wilczek; Håkan Källmén; Mirjam Ekstedt; Torbjörn Akerstedt; Mats Lekander; Rolf Ekman

    2009-01-01

    BACKGROUND: Prolonged psychosocial stress is a condition assessed through self-reports. Here we aimed to identify biochemical markers for screening and early intervention in women. METHODS: Plasma concentrations of interleukin (IL) 1-alpha, IL1-beta, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), thyroid stimulating hormone (T...

  3. Biochemical Changes During Seed Germination of Sterculia urens Roxb.

    OpenAIRE

    Botcha SATYANARAYANA; Prattipati Subhashini DEVI; Atluru ARUNDATHI

    2011-01-01

    The present study describes biochemical changes taking place during seed germination of Sterculia urens. The levels of proteins, total amino acids, reducing sugars, total soluble sugars and lipids were studied during various stages of seed germination (0-15 days). Total protein content was decreased in cotyledons during seed germination while free amino acid content increased to its maximum extent by 9th day of germination and reverse trend thereafter. The levels of reducing sugars and total ...

  4. Biological and biochemical properties in evaluation of forest soil quality

    OpenAIRE

    Błońska Ewa; Lasota Jarosław

    2014-01-01

    The aim of this study was to assess the possibility of using biological and biochemical parameters in the evaluation of forest soil quality and changes caused by land use. The study attempted to determine a relationship between the enzymatic activity of soil, the number of earthworms and soil physico-chemical properties. The study was carried out in central Poland in adjoining Forest Districts (Przedbórz and Smardzewice). In soil samples taken from 12 research plots, basic physico-chem...

  5. Biochemical profile and outcome in normal and high risk subjects

    OpenAIRE

    Vijayalaxmi, K. G.; Urooj, Asna

    2009-01-01

    The present study was carried out to assess the biochemical profile and outcome of pregnancy and study the adverse consequences if any, among normal and high risk pregnant women. The study group included 182 normal and 168 high risk cases attending to private and Government Hospitals in Bangalore. The high risk groups were: Pregnancy induced hypertension (PIH), gestational diabetes mellitus (GDM), Adolescents and anemic cases. Lipid peroxidation was enhanced in PIH and GDM groups (5.56 nmol/m...

  6. BIOCHEMICAL ALTERATIONS IN ZINC DEFICIENT SHEEP ASSOCIATED BY HYPERLACTATEMIA

    OpenAIRE

    Ali Hafez El-Far

    2013-01-01

    Blood samples from diseased and clinically healthy Balady sheep of both sexes were collected and subjected for biochemical analysis of serum glucose, fructosamine, lactate, growth hormone, insulin, creatine phosphokinase, Lactate dehydrogenase and aldolase. The obtained results revealed a significant decrease in serum zinc and growth hormone were stated. In contrary, serum glucose and lactate, insulin, CPK, LDH and aldolase were significantly increased statically. While, fructosamine levels w...

  7. Recommended Nordic paediatric reference intervals for 21 common biochemical properties

    DEFF Research Database (Denmark)

    Hilsted, Linda; Rustad, Pål; Aksglæde, Lise;

    2013-01-01

    healthy Danish children were collected for establishing reference intervals for 21 common biochemical properties (Alanine transaminase, Albumin, Alkaline phosphatase, Aspartate transaminase, Bilirubin, Calcium, Cholesterol, Creatinine, Creatine kinase, HDL-Cholesterol, Iron, Lactate dehydrogenase, LDL......- Cholesterol, Magnesium, Phosphate, Potassium, Protein, Sodium, Transferrin, Triglycerides and Urate). Samples were analyzed on a Roche-Modular-P/ISE-system. The NORIP reference material (NFKK Reference Serum X) was included in all the analytical runs. Reference values were recalculated according to the target...

  8. Biochemical functionalization of silicon dioxide surfaces for sensing applications

    OpenAIRE

    Römhildt, Lotta

    2014-01-01

    The aim of this work was to functionalize silicon dioxide surfaces with biochemical molecules in such a way that biorecognition of target molecules in solution will be possible. By introducing a tool set of different molecules and characterization methods, a more universal approach towards various biosensor setups is presented. This includes on the one hand preparation of the biosensor surfaces to allow further molecule attachment via their reactive functional groups. Secondly, the select...

  9. The role of configurational entropy in biochemical cooperativity.

    Science.gov (United States)

    Jusuf, Sutjano; Loll, Patrick J; Axelsen, Paul H

    2002-04-10

    Cooperativity is a common biochemical phenomenon in which two or more otherwise independent processes are thermodynamically coupled. Because cooperative processes are usually attended by changes in molecular conformation, thermodynamic coupling is usually attributed to an enthalpy-driven mechanism. In the family of glycopeptide antibiotics that includes vancomycin, however, cooperative phenomena occur that cannot be explained by conformational change. In this communication, we demonstrate that cooperativity in these systems can arise solely from changes in vibrational activity. PMID:11929222

  10. World War II Homefront.

    Science.gov (United States)

    Garcia, Rachel

    2002-01-01

    Presents an annotated bibliography that provides Web sites focusing on the U.S. homefront during World War II. Covers various topics such as the homefront, Japanese Americans, women during World War II, posters, and African Americans. Includes lesson plan sources and a list of additional resources. (CMK)

  11. Hepatic and biochemical repercussions of a polyunsaturated fat-rich hypercaloric and hyperlipidic diet in Wistar rats

    Directory of Open Access Journals (Sweden)

    Idália M. B. Burlamaqui

    2011-06-01

    Full Text Available CONTEXT: Non-alcoholic fatty liver disease is characterized by lipid deposits in the hepatocytes and has been associated with obesity, dyslipidemia and type-2 diabetes. It is considered a hepatic manifestation of the metabolic syndrome, of which the main component is insulin resistance leading to hyperinsulinemia and increased production of inflammatory cytokines. Saturated fat promotes hypertriglyceridemia and hyperinsulinemia, reduces levels of high-density cholesterol and increases levels of low-density cholesterol, while polyunsaturated fat is associated with hypolipidemic, antiinflammatory and imunoregulating action. OBJECTIVE: To evaluate the hepatic and biochemical repercussions of a polyunsaturated fat-rich diet in Wistar rats. METHODS: Twenty-two rats were distributed equally in two groups: GI - standard diet (Biobase Bio-tec Ratos e Camundongos® providing 3.000 kcal/kg and GII - hypercaloric and hyperlipidic diet providing 4.250 kcal/kg (ω-6:ω-3 = 3:1. The animals were euthanized after 23 weeks of experiment. The weight, biochemical parameters and hepatohistological changes were registered. RESULTS: Findings were submitted to variance analysis with the level of statistical significance at 5%. The average weight did not differ significantly between the groups at baseline (P = 0.711, but was greater in Group II by the end of the experiment (P = 0.000. The levels of triglycerides (P = 0.039, total cholesterol (P = 0.015 and HDL (P = 0.005 were higher in Group I than in Group II. Macrovesicular steatosis was significantly more common in Group II than in Group I (P = 0.03. CONCLUSION: Hypercaloric and hyperlipidic diet rich in polyunsaturated fat promotes weight gain and favors the development of hepatic steatosis while reducing serum levels of triglycerides, total cholesterol and HDL.

  12. Importance of Biochemical Markers in Postmenopausal and Senile Osteoporosis

    Directory of Open Access Journals (Sweden)

    Deniz Evcik

    2002-12-01

    Full Text Available Recently, the biochemical markers are widely used in order to evaluate the bone turnover. This study was planned to investigate the role of biochemical markers and Bone Mineral Density(BMD in postmenopausal (PMO and senile osteoporosis (SO patients. A total of 86 patients( 44 PMO, 42 SO, ages ranged between 39-79 were included in this study. Alkaline phosphatase (ALP and osteocalcin levels were determined from blood samples. Urinary deoxypyridinoline(Dpd and creatinine(cr concentration were examined and the ratio of Dpd/cr was calculated. Also BMD of the patients were measured from L1-L4 and proximal femur and t score were determined. There was no statistical difference in ALP levels between two groups. Osteocalcine and Dpd/cr levels were statistically increased in PMO group(p<0.001. According to BMD t score which was measured from proximal femur was significantly higher in SO patients(p<0.05. Our results show that biochemical markers are useful for the assessment of high-turnover osteoporosis.

  13. Polyphenol Oxidase as a Biochemical Seed Defense Mechanism

    Directory of Open Access Journals (Sweden)

    E. Patrick Fuerst

    2014-12-01

    Full Text Available Seed dormancy and resistance to decay are fundamental survival strategies, which allow a population of seeds to germinate over long periods of time. Seeds have physical, chemical, and biological defense mechanisms that protect their food reserves from decay-inducing organisms and herbivores. Here, we hypothesize that seeds also possess enzyme-based biochemical defenses, based on induction of the plant defense enzyme, polyphenol oxidase (PPO, when wild oat (Avena fatua L. caryopses and seeds were challenged with seed-decaying Fusarium fungi. These studies suggest that dormant seeds are capable of mounting a defense response to pathogens. The pathogen-induced PPO activity from wild oat was attributed to a soluble isoform of the enzyme that appeared to result, at least in part, from proteolytic activation of a latent PPO isoform. PPO activity was also induced in wild oat hulls (lemma and palea, non-living tissues that cover and protect the caryopsis. These results are consistent with the hypothesis that seeds possess inducible enzyme-based biochemical defenses arrayed on the exterior of seeds and these defenses represent a fundamental mechanism of seed survival and longevity in the soil. Enzyme-based biochemical defenses may have broader implications since they may apply to other defense enzymes as well as to a diversity of plant species and ecosystems.

  14. Weighting schemes in metabolic graphs for identifying biochemical routes.

    Science.gov (United States)

    Ghosh, S; Baloni, P; Vishveshwara, S; Chandra, N

    2014-03-01

    Metabolism forms an integral part of all cells and its study is important to understand the functioning of the system, to understand alterations that occur in disease state and hence for subsequent applications in drug discovery. Reconstruction of genome-scale metabolic graphs from genomics and other molecular or biochemical data is now feasible. Few methods have also been reported for inferring biochemical pathways from these networks. However, given the large scale and complex inter-connections in the networks, the problem of identifying biochemical routes is not trivial and some questions still remain open. In particular, how a given path is altered in perturbed conditions remains a difficult problem, warranting development of improved methods. Here we report a comparison of 6 different weighting schemes to derive node and edge weights for a metabolic graph, weights reflecting various kinetic, thermodynamic parameters as well as abundances inferred from transcriptome data. Using a network of 50 nodes and 107 edges of carbohydrate metabolism, we show that kinetic parameter derived weighting schemes [Formula: see text] fare best. However, these are limited by their extent of availability, highlighting the usefulness of omics data under such conditions. Interestingly, transcriptome derived weights yield paths with best scores, but are inadequate to discriminate the theoretical paths. The method is tested on a system of Escherichia coli stress response. The approach illustrated here is generic in nature and can be used in the analysis for metabolic network from any species and perhaps more importantly for comparing condition-specific networks.

  15. Considerations on the biochemical composition of some freshwater zooplankton species.

    Directory of Open Access Journals (Sweden)

    Nicoletta RICCARDI

    1999-02-01

    Full Text Available The mean elemental (C, H, N and biochemical composition (lipids, carbohydrates and proteins of some abundant crustacean zooplankton species of Italian insubric lakes has been estimated by the analysis of samples collected at different seasons from various environments (Lake Maggiore, Lake Varese, Lake Comabbio, Lake Monate. From each sample an adequate number of specimens of each abundant species was sorted and analyzed by a CHN elemental analyzer. The percentage of lipids, carbohydrates and proteins and the calorific content were calculated from the elemental composition according to Gnaiger & Bitterlich (1984. Inter- and intraspecific variability of biochemical composition was quite high, while elemental composition and calorific content were less variable. An estimate of the mean elemental and biochemical composition of each species was obtained by pooling the data. These mean values have been used to estimate the pools of elements and compounds in the crustacean zooplankton of Lake Comabbio to provide an example of the importance of a multiple approach in zooplankton studies.

  16. Design of a biochemical circuit motif for learning linear functions.

    Science.gov (United States)

    Lakin, Matthew R; Minnich, Amanda; Lane, Terran; Stefanovic, Darko

    2014-12-01

    Learning and adaptive behaviour are fundamental biological processes. A key goal in the field of bioengineering is to develop biochemical circuit architectures with the ability to adapt to dynamic chemical environments. Here, we present a novel design for a biomolecular circuit capable of supervised learning of linear functions, using a model based on chemical reactions catalysed by DNAzymes. To achieve this, we propose a novel mechanism of maintaining and modifying internal state in biochemical systems, thereby advancing the state of the art in biomolecular circuit architecture. We use simulations to demonstrate that the circuit is capable of learning behaviour and assess its asymptotic learning performance, scalability and robustness to noise. Such circuits show great potential for building autonomous in vivo nanomedical devices. While such a biochemical system can tell us a great deal about the fundamentals of learning in living systems and may have broad applications in biomedicine (e.g. autonomous and adaptive drugs), it also offers some intriguing challenges and surprising behaviours from a machine learning perspective. PMID:25401175

  17. BIOCHEMICAL NUTRITIONAL PROFILE OF LIVER CIRRHOSIS PATIENTS WITH HEPATOCELLULAR CARCINOMA

    Directory of Open Access Journals (Sweden)

    Gabriela Zanatta PORT

    2014-03-01

    Full Text Available Context Liver cirrhosis patients with hepatocellular carcinoma present nutritional alterations and metabolic disorders that negatively impact the prognosis. Objective The objective is to identify alterations in the metabolism of macro and micronutrients among liver cirrhosis patients with and without hepatocellular carcinoma and their relation to the Child-Turcote-Pugh score and Barcelona Clinic Liver Cancer staging. Methods Analytical transversal study, with 31 hepatocellular carcinoma patients and 48 liver cirrhosis patients. Laboratorial exams were carried out. The existence of an association between the biochemical parameters and the disease severity as well as the presence of hepatocellular carcinoma was assessed. Results The metabolic-nutritional profile of liver cirrhosis patients caused by the hepatitis C virus and hepatocellular carcinoma showed alterations, specifically the lipid (total cholesterol, HDL and triglycerides, protein (albumin, creatinine and uric acid, iron (transferrin, iron and ferritin saturation, hematocrit and hemoglobin, zinc and B12 vitamin profiles. There is a relation between nutritional biochemical markers and the Child-Turcote-Pugh, as well as Barcelona Clinic Liver Cancer staging. Conclusions Considering the existence of alterations in the metabolism of nutrients in liver cirrhosis patients with and without hepatocellular carcinoma, and also that conventional nutritional assessment methods present limitations for this population, the biochemical laboratorial exams are valid to complement the diagnosis of the nutritional state in a quick and practical manner.

  18. Biochemical Characterization of Hypothetical Proteins from Helicobacter pylori.

    Directory of Open Access Journals (Sweden)

    Han-Pil Choi

    Full Text Available The functional characterization of Open Reading Frames (ORFs from sequenced genomes remains a bottleneck in our effort to understand microbial biology. In particular, the functional characterization of proteins with only remote sequence homology to known proteins can be challenging, as there may be few clues to guide initial experiments. Affinity enrichment of proteins from cell lysates, and a global perspective of protein function as provided by COMBREX, affords an approach to this problem. We present here the biochemical analysis of six proteins from Helicobacter pylori ATCC 26695, a focus organism in COMBREX. Initial hypotheses were based upon affinity capture of proteins from total cellular lysate using derivatized nano-particles, and subsequent identification by mass spectrometry. Candidate genes encoding these proteins were cloned and expressed in Escherichia coli, and the recombinant proteins were purified and characterized biochemically and their biochemical parameters compared with the native ones. These proteins include a guanosine triphosphate (GTP cyclohydrolase (HP0959, an ATPase (HP1079, an adenosine deaminase (HP0267, a phosphodiesterase (HP1042, an aminopeptidase (HP1037, and new substrates were characterized for a peptidoglycan deacetylase (HP0310. Generally, characterized enzymes were active at acidic to neutral pH (4.0-7.5 with temperature optima ranging from 35 to 55°C, although some exhibited outstanding characteristics.

  19. Relationship between cellular response models and biochemical mechanisms

    International Nuclear Information System (INIS)

    In most cellular response experiments, survival reflects the kinetics of a variety of damage and repair processes. Unfortunately, biochemical studies of molecular repair deal with mechanisms which cannot be readily correlated with these kinetic observations. The difference in these approaches sometimes leads to confusion over terms such as potentially-lethal and sublethal damage. These terms were introduced with operation definitions, derived from kinetic studies of cell survival, but some researchers have since attempted to associate them with specific biochemical mechanisms. Consequently, the terms are often used in totally different ways be different investigators. The use of carefully constructed models originating either out of assumptions based on mechanisms, or on kinetics, can be used to design experiments to eliminate some alternative kinetic schemes. In turn, some mechanisms may also be eliminated, resulting in a reduction in the number of mechanisms which must be investigated biochemically. One must take advantage of a wide range of specialized radiation procedures in order to accomplish this. Examples of the use of such specialized experimental designs, which have led to a more detailed understanding of the kinetics of both algal and mammalian cell responses, are discussed

  20. Moorella Strains for the Production of Biochemicals from Syngas

    DEFF Research Database (Denmark)

    Redl, Stephanie; Jensen, Torbjørn Ølshøj; Nielsen, Alex Toftgaard

    In the process of sugar fermentation, a significant portion of lignocellulosic biomass is left unused. An alternative is the gasification into syngas, a carbon-rich gas mixture. Syngas serves as energy and carbon source for acetogenic bacteria, which can then produce biochemicals. In the syngas f...... gene expression was constructed. These tools developed in my project will be applied to engineer bacterial cell factories for production of higher value biochemicals like acetone.......In the process of sugar fermentation, a significant portion of lignocellulosic biomass is left unused. An alternative is the gasification into syngas, a carbon-rich gas mixture. Syngas serves as energy and carbon source for acetogenic bacteria, which can then produce biochemicals. In the syngas...... fermentation process even the recalcitrant lignin portion can be fully converted into higher value compounds. Still the cost-effectiveness of this process requires better understanding of the metabolism and modification of the acetogenic strains. In my PhD project I am laying the basis for production of higher...