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Sample records for hybrids f2 mice

  1. The E2F2 transcription factor sustains hepatic glycerophospholipid homeostasis in mice.

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    Eduardo N Maldonado

    Full Text Available Increasing evidence links metabolic signals to cell proliferation, but the molecular wiring that connects the two core machineries remains largely unknown. E2Fs are master regulators of cellular proliferation. We have recently shown that E2F2 activity facilitates the completion of liver regeneration after partial hepatectomy (PH by regulating the expression of genes required for S-phase entry. Our study also revealed that E2F2 determines the duration of hepatectomy-induced hepatic steatosis. A transcriptomic analysis of normal adult liver identified "lipid metabolism regulation" as a major E2F2 functional target, suggesting that E2F2 has a role in lipid homeostasis. Here we use wild-type (E2F2+/+ and E2F2 deficient (E2F2-/- mice to investigate the in vivo role of E2F2 in the composition of liver lipids and fatty acids in two metabolically different contexts: quiescence and 48-h post-PH, when cellular proliferation and anabolic demands are maximal. We show that liver regeneration is accompanied by large triglyceride and protein increases without changes in total phospholipids both in E2F2+/+ and E2F2-/- mice. Remarkably, we found that the phenotype of quiescent liver tissue from E2F2-/- mice resembles the phenotype of proliferating E2F2+/+ liver tissue, characterized by a decreased phosphatidylcholine to phosphatidylethanolamine ratio and a reprogramming of genes involved in generation of choline and ethanolamine derivatives. The diversity of fatty acids in total lipid, triglycerides and phospholipids was essentially preserved on E2F2 loss both in proliferating and non-proliferating liver tissue, although notable exceptions in inflammation-related fatty acids of defined phospholipid classes were detected. Overall, our results indicate that E2F2 activity sustains the hepatic homeostasis of major membrane glycerolipid components while it is dispensable for storage glycerolipid balance.

  2. Megaspore competition in F1 and F2 hybrids between Oenothera hookeri and Oe. suaveolens

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    Renata Śnieżko

    2014-01-01

    Full Text Available Megasporogenesis and development of the embryo sac were investigated in F1 and F2 hybrids from crosses of Oe. hookeri and Oe. suaveolens. All hybrids form heteropolar and homopolar magaspore tetrads; the embryo sac, however, usually develops from the micropylar megaspore. Its development may occur immediately after degeneration of three other megaspores or after a period of competition between both apical megaspores. They develop simultaneously for a relatively short time, after which the growth of the chalazal megaspore is inhibited, although the latter does not degenerate. The micropylar megaspore as a rule develops without disturbances into the embryo sac, but in some ovules it is formed from the chalazal megaspore or double ones arise from both apical megaspores of the tetrad. The frequency of the micropylar embryo sac formation seems to be dependent above all on the hybrid plant genome and not on the haploid genome of the megaspore.

  3. Major urinary metabolites of 6-keto-prostaglandin F2α in mice[S

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    Kuklev, Dmitry V.; Hankin, Joseph A.; Uhlson, Charis L.; Hong, Yu H.; Murphy, Robert C.; Smith, William L.

    2013-01-01

    Western diets are enriched in omega-6 vs. omega-3 fatty acids, and a shift in this balance toward omega-3 fatty acids may have health benefits. There is limited information about the catabolism of 3-series prostaglandins (PG) formed from eicosapentaenoic acid (EPA), a fish oil omega-3 fatty acid that becomes elevated in tissues following fish oil consumption. Quantification of appropriate urinary 3-series PG metabolites could be used for noninvasive measurement of omega-3 fatty acid tone. Here we describe the preparation of tritium- and deuterium-labeled 6-keto-PGF2α and their use in identifying urinary metabolites in mice using LC-MS/MS. The major 6-keto-PGF2α urinary metabolites included dinor-6-keto-PGF2α (∼10%) and dinor-13,14-dihydro-6,15-diketo-PGF1α (∼10%). These metabolites can arise only from the enzymatic conversion of EPA to the 3-series PGH endoperoxide by cyclooxygenases, then PGI3 by prostacyclin synthase and, finally, nonenzymatic hydrolysis to 6-keto-PGF2α. The 6-keto-PGF derivatives are not formed by free radical mechanisms that generate isoprostanes, and thus, these metabolites provide an unbiased marker for utilization of EPA by cyclooxygenases. PMID:23644380

  4. Genetics and evolution of hybrid male sterility in house mice.

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    White, Michael A; Stubbings, Maria; Dumont, Beth L; Payseur, Bret A

    2012-07-01

    Comparative genetic mapping provides insights into the evolution of the reproductive barriers that separate closely related species. This approach has been used to document the accumulation of reproductive incompatibilities over time, but has only been applied to a few taxa. House mice offer a powerful system to reconstruct the evolution of reproductive isolation between multiple subspecies pairs. However, studies of the primary reproductive barrier in house mice-hybrid male sterility-have been restricted to a single subspecies pair: Mus musculus musculus and Mus musculus domesticus. To provide a more complete characterization of reproductive isolation in house mice, we conducted an F(2) intercross between wild-derived inbred strains from Mus musculus castaneus and M. m. domesticus. We identified autosomal and X-linked QTL associated with a range of hybrid male sterility phenotypes, including testis weight, sperm density, and sperm morphology. The pseudoautosomal region (PAR) was strongly associated with hybrid sterility phenotypes when heterozygous. We compared QTL found in this cross with QTL identified in a previous F(2) intercross between M. m. musculus and M. m. domesticus and found three shared autosomal QTL. Most QTL were not shared, demonstrating that the genetic basis of hybrid male sterility largely differs between these closely related subspecies pairs. These results lay the groundwork for identifying genes responsible for the early stages of speciation in house mice.

  5. Diabetes and exocrine pancreatic insufficiency in E2F1/E2F2 double-mutant mice.

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    Iglesias, Ainhoa; Murga, Matilde; Laresgoiti, Usua; Skoudy, Anouchka; Bernales, Irantzu; Fullaondo, Asier; Moreno, Bernardino; Lloreta, José; Field, Seth J; Real, Francisco X; Zubiaga, Ana M

    2004-05-01

    E2F transcription factors are thought to be key regulators of cell growth control. Here we use mutant mouse strains to investigate the function of E2F1 and E2F2 in vivo. E2F1/E2F2 compound-mutant mice develop nonautoimmune insulin-deficient diabetes and exocrine pancreatic dysfunction characterized by endocrine and exocrine cell dysplasia, a reduction in the number and size of acini and islets, and their replacement by ductal structures and adipose tissue. Mutant pancreatic cells exhibit increased rates of DNA replication but also of apoptosis, resulting in severe pancreatic atrophy. The expression of genes involved in DNA replication and cell cycle control was upregulated in the E2F1/E2F2 compound-mutant pancreas, suggesting that their expression is repressed by E2F1/E2F2 activities and that the inappropriate cell cycle found in the mutant pancreas is likely the result of the deregulated expression of these genes. Interestingly, the expression of ductal cell and adipocyte differentiation marker genes was also upregulated, whereas expression of pancreatic cell marker genes were downregulated. These results suggest that E2F1/E2F2 activity negatively controls growth of mature pancreatic cells and is necessary for the maintenance of differentiated pancreatic phenotypes in the adult.

  6. The Pace of Hybrid Incompatibility Evolution in House Mice.

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    Wang, Richard J; White, Michael A; Payseur, Bret A

    2015-09-01

    Hybrids between species are often sterile or inviable. This form of reproductive isolation is thought to evolve via the accumulation of mutations that interact to reduce fitness when combined in hybrids. Mathematical formulations of this "Dobzhansky-Muller model" predict an accelerating buildup of hybrid incompatibilities with divergence time (the "snowball effect"). Although the Dobzhansky-Muller model is widely accepted, the snowball effect has only been tested in two species groups. We evaluated evidence for the snowball effect in the evolution of hybrid male sterility among subspecies of house mice, a recently diverged group that shows partial reproductive isolation. We compared the history of subspecies divergence with patterns of quantitative trait loci (QTL) detected in F2 intercrosses between two pairs of subspecies (Mus musculus domesticus with M. m. musculus and M. m. domesticus with M. m. castaneus). We used a recently developed phylogenetic comparative method to statistically measure the fit of these data to the snowball prediction. To apply this method, QTL were partitioned as either shared or unshared in the two crosses. A heuristic partitioning based on the overlap of QTL confidence intervals produced unambiguous support for the snowball effect. An alternative approach combining data among crosses favored the snowball effect for the autosomes, but a linear accumulation of incompatibilities for the X chromosome. Reasoning that the X chromosome analyses are complicated by low mapping resolution, we conclude that hybrid male sterility loci have snowballed in house mice. Our study illustrates the power of comparative genetic mapping for understanding mechanisms of speciation. Copyright © 2015 by the Genetics Society of America.

  7. Irradiation effect on F2 segregation for earliness, productiveness and fibre length in Gossypium hirsutum x G. barbadense hybridization

    International Nuclear Information System (INIS)

    Stoilova, A.

    1984-01-01

    Two hybrid combinations between cv. Chirpan-433 (of the species G. hirsutum) and C-6030 and 5904-I (of the species G. barbadense) were studied. F 0 seeds were irradiated by 30 krad. Non-irradiated seeds were used as control. It was found that hybrid irradiation affected segregation of the characters in a different way. It retarded ripening, the negative effect being higher in the combination Chirpan-433x5904-N. In respect to productiveness and fibre lenght hybrid irradiation led to positive changes in the form-producing process. Hibrids of the combination Chirpan-433X5904-I responded more favourably to irradiation in respect to these two characters. Hybrid irradiation altered the type of segregation and created suplementary pool of forms with desired characters, increasing the possibilities of interspecific hybridization to combine the valuable economic characters of both species

  8. Use of the mice passive protection test to evaluate the humoral response in goats vaccinated with Sterne 34F2 live spore vaccine.

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    Phaswana, P H; Ndumnego, O C; Koehler, S M; Beyer, W; Crafford, J E; van Heerden, H

    2017-09-07

    The Sterne live spore vaccine (34F2) is the most widely used veterinary vaccine against anthrax in animals. Antibody responses to several antigens of Bacillus anthracis have been described with a large focus on those against protective antigen (PA). The focus of this study was to evaluate the protective humoral immune response induced by the live spore anthrax vaccine in goats. Boer goats vaccinated twice (week 0 and week 12) with the Sterne live spore vaccine and naive goats were used to monitor the anti-PA and toxin neutralizing antibodies at week 4 and week 17 (after the second vaccine dose) post vaccination. A/J mice were passively immunized with different dilutions of sera from immune and naive goats and then challenged with spores of B. anthracis strain 34F2 to determine the protective capacity of the goat sera. The goat anti-PA ELISA titres indicated significant sero-conversion at week 17 after the second doses of vaccine (p = 0.009). Mice receiving undiluted sera from goats given two doses of vaccine (twice immunized) showed the highest protection (86%) with only 20% of mice receiving 1:1000 diluted sera surviving lethal challenge. The in vitro toxin neutralization assay (TNA) titres correlated to protection of passively immunized A/J mice against lethal infection with the vaccine strain Sterne 34F2 spores using immune goat sera up to a 1:10 dilution (r s  ≥ 0.522, p = 0.046). This study suggests that the passive mouse protection model could be potentially used to evaluate the protective immune response in livestock animals vaccinated with the current live vaccine and new vaccines.

  9. Virulent PB1-F2 residues: effects on fitness of H1N1 influenza A virus in mice and changes during evolution of human influenza A viruses.

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    Alymova, Irina V; McCullers, Jonathan A; Kamal, Ram P; Vogel, Peter; Green, Amanda M; Gansebom, Shane; York, Ian A

    2018-05-10

    Specific residues of influenza A virus (IAV) PB1-F2 proteins may enhance inflammation or cytotoxicity. In a series of studies, we evaluated the function of these virulence-associated residues in the context of different IAV subtypes in mice. Here, we demonstrate that, as with the previously assessed pandemic 1968 (H3N2) IAV, PB1-F2 inflammatory residues increase the virulence of H1N1 IAV, suggesting that this effect might be a universal feature. Combining both inflammatory and cytotoxic residues in PB1-F2 enhanced virulence further, compared to either motif alone. Residues from these virulent motifs have been present in natural isolates from human seasonal IAV of all subtypes, but there has been a trend toward a gradual reduction in the number of virulent residues over time. However, human IAV of swine and avian origin tend to have more virulent residues than do the human-adapted seasonal strains, raising the possibility that donation of PB1 segments from these zoonotic viruses may increase the severity of some seasonal human strains. Our data suggest the value of surveillance of virulent residues in both human and animal IAV to predict the severity of influenza season.

  10. Depressed levels of prostaglandin F2α in mice lacking Akr1b7 increase basal adiposity and predispose to diet-induced obesity.

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    Volat, Fanny E; Pointud, Jean-Christophe; Pastel, Emilie; Morio, Béatrice; Sion, Benoit; Hamard, Ghislaine; Guichardant, Michel; Colas, Romain; Lefrançois-Martinez, Anne-Marie; Martinez, Antoine

    2012-11-01

    Negative regulators of white adipose tissue (WAT) expansion are poorly documented in vivo. Prostaglandin F(2α) (PGF(2α)) is a potent antiadipogenic factor in cultured preadipocytes, but evidence for its involvement in physiological context is lacking. We previously reported that Akr1b7, an aldo-keto reductase enriched in adipose stromal vascular fraction but absent from mature adipocytes, has antiadipogenic properties possibly supported by PGF(2α) synthase activity. To test whether lack of Akr1b7 could influence WAT homeostasis in vivo, we generated Akr1b7(-/-) mice in 129/Sv background. Akr1b7(-/-) mice displayed excessive basal adiposity resulting from adipocyte hyperplasia/hypertrophy and exhibited greater sensitivity to diet-induced obesity. Following adipose enlargement and irrespective of the diet, they developed liver steatosis and progressive insulin resistance. Akr1b7 loss was associated with decreased PGF(2α) WAT contents. Cloprostenol (PGF(2α) agonist) administration to Akr1b7(-/-) mice normalized WAT expansion by affecting both de novo adipocyte differentiation and size. Treatment of 3T3-L1 adipocytes and Akr1b7(-/-) mice with cloprostenol suggested that decreased adipocyte size resulted from inhibition of lipogenic gene expression. Hence, Akr1b7 is a major regulator of WAT development through at least two PGF(2α)-dependent mechanisms: inhibition of adipogenesis and lipogenesis. These findings provide molecular rationale to explore the status of aldo-keto reductases in dysregulations of adipose tissue homeostasis.

  11. QTL analysis of dietary obesity in C57BL/6byj X 129P3/J F2 mice: diet- and sex-dependent effects.

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    Lin, Cailu; Theodorides, Maria L; McDaniel, Amanda H; Tordoff, Michael G; Zhang, Qinmin; Li, Xia; Bosak, Natalia; Bachmanov, Alexander A; Reed, Danielle R

    2013-01-01

    Obesity is a heritable trait caused by complex interactions between genes and environment, including diet. Gene-by-diet interactions are difficult to study in humans because the human diet is hard to control. Here, we used mice to study dietary obesity genes, by four methods. First, we bred 213 F2 mice from strains that are susceptible [C57BL/6ByJ (B6)] or resistant [129P3/J (129)] to dietary obesity. Percent body fat was assessed after mice ate low-energy diet and again after the same mice ate high-energy diet for 8 weeks. Linkage analyses identified QTLs associated with dietary obesity. Three methods were used to filter candidate genes within the QTL regions: (a) association mapping was conducted using >40 strains; (b) differential gene expression and (c) comparison of genomic DNA sequence, using two strains closely related to the progenitor strains from Experiment 1. The QTL effects depended on whether the mice were male or female or which diet they were recently fed. After feeding a low-energy diet, percent body fat was linked to chr 7 (LOD=3.42). After feeding a high-energy diet, percent body fat was linked to chr 9 (Obq5; LOD=3.88), chr 12 (Obq34; LOD=3.88), and chr 17 (LOD=4.56). The Chr 7 and 12 QTLs were sex dependent and all QTL were diet-dependent. The combination of filtering methods highlighted seven candidate genes within the QTL locus boundaries: Crx, Dmpk, Ahr, Mrpl28, Glo1, Tubb5, and Mut. However, these filtering methods have limitations so gene identification will require alternative strategies, such as the construction of congenics with very small donor regions.

  12. Single hind limb burn injury to mice alters nuclear factor-κB expression and [¹⁸F] 2-fluoro-2-deoxy-D-glucose uptake.

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    Carter, Edward A; Hamrahi, Victoria; Paul, Kasie; Bonab, Ali A; Jung, Walter; Tompkins, Ronald G; Fischman, Alan J

    2014-01-01

    Burn trauma to the extremities can produce marked systemic effects in mice. Burn injury to the dorsal surface of mice is also associated with changes in glucose metabolism ([18F] 2-fluoro-2-deoxy-D-glucose [18FDG] uptake) by brown adipose tissue (BAT) and nuclear factor (NF)-κB activity in several tissues including skeletal muscle. This study examined the effect of a single hind limb burn in mice on 18FDG uptake by NF-κB activity in vivo, and blood flow was determined by laser Doppler techniques. Male NF-κB luciferase reporter mice (28-30 g) were anesthetized, both legs were shaven, and the right leg was subjected to scald injury by immersion in 90°C water for 5 seconds. Sham-treated animals were used as controls. Each burned and sham mouse was resuscitated with saline (2 mL, i.p.). The individual animals were placed in wire bottom cages with no food and free access to water. After 24 hours, the animals were imaged with laser Doppler for measuring blood flow in the hind limb. The animals were then unanesthetized with 50 μCi of FDG or luciferin (1.0 mg, i.v.) via tail vein. Five minutes after luciferin injection, NF-κB mice were studied by bioluminescence imaging with a charge-coupled device camera. One hour after 18FDG injection, the animals were killed with carbon dioxide overdose, and 18FDG biodistribution was measured. Tissues were also analyzed for NF-κB luciferase activity. The scalding procedure used here produced a full-thickness burn injury to the leg with sharp margins. 18FDG uptake by the burned leg was lower than that in the contralateral limb. Similarly, luciferase activity and blood flow in the burned leg were lower than those in the contralateral leg. 18FDG uptake by BAT and heart increased, whereas that by brain decreased. In conclusion, the present study suggests that burn injury to a single leg decreased FDG uptake by skeletal muscle but increased 18FDG uptake by BAT. The injury to the leg reduced NF-κB expression compared with the

  13. The Evolution of Polymorphic Hybrid Incompatibilities in House Mice.

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    Larson, Erica L; Vanderpool, Dan; Sarver, Brice A J; Callahan, Colin; Keeble, Sara; Provencio, Lorraine P; Kessler, Michael D; Stewart, Vanessa; Nordquist, Erin; Dean, Matthew D; Good, Jeffrey M

    2018-04-24

    Resolving the mechanistic and genetic bases of reproductive barriers between species is essential to understanding the evolutionary forces that shape speciation. Intrinsic hybrid incompatibilities are often treated as fixed between species, yet there can be considerable variation in the strength of reproductive isolation between populations. The extent and causes of this variation remain poorly understood in most systems. We investigated the genetic basis of variable hybrid male sterility (HMS) between two recently diverged subspecies of house mice, Mus musculus domesticus and M. m. musculus We found that polymorphic HMS has a surprisingly complex genetic basis, with contributions from at least five autosomal loci segregating between two closely related wild-derived strains of M. m. musculus One of the HMS-linked regions on Chromosome 4 also showed extensive introgression among inbred laboratory strains and transmission ratio distortion (TRD) in hybrid crosses. Using additional crosses and whole genome sequencing of sperm pools, we showed that TRD was limited to hybrid crosses and was not due to differences in sperm motility between M. m. musculus strains. Based on these results, we argue that TRD likely reflects additional incompatibilities that reduce hybrid embryonic viability. In some common inbred strains of mice, selection against deleterious interactions appears to have unexpectedly driven introgression at loci involved in epistatic hybrid incompatibilities. The highly variable genetic basis to F1 hybrid incompatibilities between closely related mouse lineages argues that a thorough dissection of reproductive isolation will require much more extensive sampling of natural variation than has been commonly utilized in mice and other model systems. Copyright © 2018, Genetics.

  14. Prostaglandin F2alpha- and FAS-activating antibody-induced regression of the corpus luteum involves caspase-8 and is defective in caspase-3 deficient mice

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    Flavell Richard A

    2003-02-01

    Full Text Available Abstract We recently demonstrated that caspase-3 is important for apoptosis during spontaneous involution of the corpus luteum (CL. These studies tested if prostaglandin F2α (PGF2α or FAS regulated luteal regression, utilize a caspase-3 dependent pathway to execute luteal cell apoptosis, and if the two receptors work via independent or potentially shared intracellular signaling components/pathways to activate caspase-3. Wild-type (WT or caspase-3 deficient female mice, 25–26 days old, were given 10 IU equine chorionic gonadotropin (eCG intraperitoneally (IP followed by 10 IU human chorionic gonadotropin (hCG IP 46 h later to synchronize ovulation. The animals were then injected with IgG (2 micrograms, i.v., the FAS-activating antibody Jo2 (2 micrograms, i.v., or PGF2α (10 micrograms, i.p. at 24 or 48 h post-ovulation. Ovaries from each group were collected 8 h later for assessment of active caspase-3 enzyme and apoptosis (measured by the TUNEL assay in the CL. Regardless of genotype or treatment, CL in ovaries collected from mice injected 24 h after ovulation showed no evidence of active caspase-3 or apoptosis. However, PGF2α or Jo2 at 48 h post-ovulation and collected 8 h later induced caspase-3 activation in 13.2 ± 1.8% and 13.7 ± 2.2 % of the cells, respectively and resulted in 16.35 ± 0.7% (PGF2α and 14.3 ± 2.5% TUNEL-positive cells when compared to 1.48 ± 0.8% of cells CL in IgG treated controls. In contrast, CL in ovaries collected from caspase-3 deficient mice whether treated with PGF2α , Jo2, or control IgG at 48 h post-ovulation showed little evidence of active caspase-3 or apoptosis. CL of WT mice treated with Jo2 at 48 h post-ovulation had an 8-fold increase in the activity of caspase-8, an activator of caspase-3 that is coupled to the FAS death receptor. Somewhat unexpectedly, however, treatment of WT mice with PGF2α at 48 h post-ovulation resulted in a 22-fold increase in caspase-8 activity in the CL, despite the fact

  15. Proteomic Analysis of Pachytene Spermatocytes of Sterile Hybrid Male Mice.

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    Wang, Lu; Guo, Yueshuai; Liu, Wenjing; Zhao, Weidong; Song, Gendi; Zhou, Tao; Huang, Hefeng; Guo, Xuejiang; Sun, Fei

    2016-09-01

    Incompatibilities in interspecific hybrids, such as reduced hybrid fertility and lethality, are common features resulting from reproductive isolation that lead to speciation. Subspecies crosses of house mice produce offspring in which one sex is infertile or absent, yet the molecular mechanisms of hybrid sterility are poorly understood. In this study, we observed extensive asynapsis of chromosomes and disturbance of the sex body in pachytene spermatocytes of sterile F1 males (PWK/Ph female × C57BL/6J male). We report the high-confidence identification of 4005 proteins in the pachytene spermatocytes of fertile F1 males (PWK/Ph male × C57BL/6J female) and sterile F1 males (PWK/Ph female × C57BL/6J male), of which 215 were upregulated and 381 were downregulated. Bioinformatics analysis of the proteome led to the identification of 43 and 59 proteins known to be essential for male meiosis and spermatogenesis in mice, respectively. Characterization of the proteome of pachytene spermatocytes associated with hybrid male sterility provides an inventory of proteins that is useful for understanding meiosis and the mechanisms of hybrid male infertility. © 2016 by the Society for the Study of Reproduction, Inc.

  16. Parental bone marrow growth in young hybrid mice

    International Nuclear Information System (INIS)

    Chervenak, R.P.

    1979-01-01

    When bone marrow is transplated from certain inbred mouse strains to F 1 hybrids of that strain, the graft often fails to proliferate. It has been reported that this phenomenon, known as Poor Growth, is not demonstrable in recipients less than three weeks of age. The purpose of the present study was to investigate some of the parameters involved in this phenomenon and its sudden appearance at three weeks of age. By employing 125 IUdR uptake and hemopoietic colony assays following transplantation of marrow to mice of various ages and treatment groups, the following conclusions were drawn. (1) Parental marrow grew equally well in both parental strain and F 1 hybrid recipients less than three weeks old; (2) The observed growth of hemopoietic tissue was not due to endogeneous stem cell proliferation; (3) Changes in radiation sensitivity did not account for the fluctuations of hemopoiesis seen in mice from one to five weeks of age; (4) Neither stimulator cells in mice less than three weeks of age nor graft destroying cells in older mice could be demonstrated. Two mechanistic models of Poor Growth are presented and discussed and a new model is proposed

  17. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa com arroz transgênico (O. sativa resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa with ammonium-glufosinate-resistant transgenic rice (O. sativa

    Directory of Open Access Journals (Sweden)

    J.A. Noldin

    2004-09-01

    -preto. Mesmo assim, os usuários dessa tecnologia deverão adotar, obrigatoriamente, medidas que evitem a possibilidade de cruzamento entre o arroz transgênico e o arroz-vermelho ou arroz-preto.Red rice is an important weed in paddy rice fields. The use of ammonium glufosinate - resistant genetically modified (GM rice cultivars is a viable alternative for controlling red rice in cultivated rice crops. The objective of this study was to evaluate the behavior of F2 hybrid population derivates of crossing between ammonium glufosinate - resistant GM rice and red rice. The F2 hybrid population derivates of crossing between GM rice and red rice are viable but do not present any apparent competitive advantage over red rice. The morphological characteristics of the F2 hybrid populations, such as tillering capacity, number of leaves produced and average plant height were partly reduced and partly unaffected by the introgression of the bar gene. The period between rice planting and 50% flowering increased in the red rice x GM rice F2 hybrids, compared to the parental red rice and GM rice. Average seed shattering rate in the four hybrid families was lower than in the red rice ecotypes, with such aspect also being unfavorable to the persistence of red rice in the environment. Seed dormancy of the hybrids was similar to that of the red rice ecotypes. However, management practices should be adopted to avoid crossing between transgenic rice and red rice.

  18. Single Hind Limb Burn Injury to Mice Alters NF Kappa B (NF-κB) Expression and [18F] 2-Fluoro-2-Deoxy-d-Glucose (FDG) Uptake

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    Carter, Edward A.; Hamrahi, Victoria; Paul, Kasie; Bonab, Ali A.; Jung, Walter; Tompkins, Ronald G.; Fischman, Alan J.

    2014-01-01

    Burn trauma to the extremities can produce marked systemic effects in mice1, 6, 7. Burn injury to the dorsal surface of mice is also associated with changes in glucose metabolism (18FDG uptake) by brown adipose tissue (BAT) and NF-κB activity in a number of tissues including skeletal muscle. This study examined the effect of a single hindlimb burn in mice on 18FDG uptake by in vivo, NF-κB activity in vivo, and blood flow determined by laser Doppler techniques. Male mice NF-κB luciferase repor...

  19. Investigation into the MgF2-NiF2, CaF2-NiF2, SrF2-NiF2 systems

    International Nuclear Information System (INIS)

    Ikrami, D.D.; Petrov, S.V.; Fedorov, P.P.; Ol'khovaya, L.A.; Luginina, A.A.; AN SSSR, Moscow. Inst. Fizicheskikh Problem; AN SSSR, Moscow. Inst. Kristallografii)

    1984-01-01

    Using the methods of differential thermal and X-ray phase analyses the systems MgF 2 -NiF 2 , CaF 2 -NiF 2 , SrF 2 -NiF 2 have been studied. In the system SrF 2 -NiF 2 the only orthorhombic compounds SrNiF 4 (a=14.43; b=3.93; c=5.66 (+-0.01 A)) is formed. SrNiF 4 density constitutes: dsub(X-ray)=4.60+-0.01 g/cm 3 , dsub(exp.)=4.60+-0.03 g/cm 3 . Refraction indices are as follows SrNiF 4 :Ng=1.500; Nsub(m)=1.497; Nsub(p)=1.479. SrNiF 4 magnetic ordering temperature Tsub(N) approximately 100 K

  20. Single Hind Limb Burn Injury to Mice Alters NF Kappa B (NF-κB) Expression and [18F] 2-Fluoro-2-Deoxy-d-Glucose (FDG) Uptake

    Science.gov (United States)

    Carter, Edward A.; Hamrahi, Victoria; Paul, Kasie; Bonab, Ali A.; Jung, Walter; Tompkins, Ronald G.; Fischman, Alan J.

    2014-01-01

    Burn trauma to the extremities can produce marked systemic effects in mice1, 6, 7. Burn injury to the dorsal surface of mice is also associated with changes in glucose metabolism (18FDG uptake) by brown adipose tissue (BAT) and NF-κB activity in a number of tissues including skeletal muscle. This study examined the effect of a single hindlimb burn in mice on 18FDG uptake by in vivo, NF-κB activity in vivo, and blood flow determined by laser Doppler techniques. Male mice NF-κB luciferase reporter mice (28 grams- 30 grams, male) were anesthetized, both legs were shaven, and the right leg was subjected to scald injury by immersion in 90°C water for 5 seconds. Sham treated animals were used as controls. Each burned and sham mouse was resuscitated with saline (2 ml, IP). The individual animals were placed in wire bottom cages with no food and free access to water. 24 hrs later, the animals were imaged with Laser Doppler for measurements of blood flow in the hind limb. The animals were then injected unanesthetized with 50 µCi of FDG or luciferin (1.0 mg), I.V. via tail vein. Five minutes after luciferin injection, NF-kB mice were studied by bioluminescence imaging with a CCD camera. One hour after 18FDG injection the animals were euthanized with carbon dioxide overdose and 18FDG biodistribution was measured. Tissues were also analyzed for NF-κB luciferase activity. The scalding procedure used here produced a full thickness burn injury to the leg with sharp margins. 18FDG uptake by the burned leg was lower than in the contralateral limb. Similarly luciferase activity and blood flow in the burned leg were lower than in the contralateral leg. 18FDG uptake by BAT and heart was increased, while brain was decreased. In conclusion, the present study suggests that burn injury to a single leg reduced 18FDG uptake by skeletal muscle but increased 18FDG uptake by BAT. The injury to the leg reduced NF-κB expression as compared to the contralateral leg and the uninjured

  1. Candidate Gene Identification of Feed Efficiency and Coat Color Traits in a C57BL/6J × Kunming F2 Mice Population Using Genome-Wide Association Study.

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    Miao, Yuanxin; Soudy, Fathia; Xu, Zhong; Liao, Mingxing; Zhao, Shuhong; Li, Xinyun

    2017-01-01

    Feed efficiency (FE) is a very important trait in livestock industry. Identification of the candidate genes could be of benefit for the improvement of FE trait. Mouse is used as the model for many studies in mammals. In this study, the candidate genes related to FE and coat color were identified using C57BL/6J (C57) × Kunming (KM) F2 mouse population. GWAS results showed that 61 and 2 SNPs were genome-wise suggestive significantly associated with feed conversion ratio (FCR) and feed intake (FI) traits, respectively. Moreover, the Erbin, Msrb2, Ptf1a, and Fgf10 were considered as the candidate genes of FE. The Lpl was considered as the candidate gene of FI. Further, the coat color trait was studied. KM mice are white and C57 ones are black. The GWAS results showed that the most significant SNP was located at chromosome 7, and the closely linked gene was Tyr. Therefore, our study offered useful target genes related to FE in mice; these genes may play similar roles in FE of livestock. Also, we identified the major gene of coat color in mice, which would be useful for better understanding of natural mutation of the coat color in mice.

  2. Candidate Gene Identification of Feed Efficiency and Coat Color Traits in a C57BL/6J × Kunming F2 Mice Population Using Genome-Wide Association Study

    Directory of Open Access Journals (Sweden)

    Yuanxin Miao

    2017-01-01

    Full Text Available Feed efficiency (FE is a very important trait in livestock industry. Identification of the candidate genes could be of benefit for the improvement of FE trait. Mouse is used as the model for many studies in mammals. In this study, the candidate genes related to FE and coat color were identified using C57BL/6J (C57 × Kunming (KM F2 mouse population. GWAS results showed that 61 and 2 SNPs were genome-wise suggestive significantly associated with feed conversion ratio (FCR and feed intake (FI traits, respectively. Moreover, the Erbin, Msrb2, Ptf1a, and Fgf10 were considered as the candidate genes of FE. The Lpl was considered as the candidate gene of FI. Further, the coat color trait was studied. KM mice are white and C57 ones are black. The GWAS results showed that the most significant SNP was located at chromosome 7, and the closely linked gene was Tyr. Therefore, our study offered useful target genes related to FE in mice; these genes may play similar roles in FE of livestock. Also, we identified the major gene of coat color in mice, which would be useful for better understanding of natural mutation of the coat color in mice.

  3. Variability and Character Association in F2 Segregating Population ...

    African Journals Online (AJOL)

    Michael Horsfall

    Department of Genetics and Plant Breeding, 1Department of Horticulture. Bangabandhu Sheikh Mujibur Rahman Agricultural University. Gazipur 1706, Bangladesh. ABSTRACT: The F2 segregating generations of exotic tomato hybrids were studied to measure variability, character association and path coefficient analysis.

  4. Speciation and reduced hybrid female fertility in house mice.

    Science.gov (United States)

    Suzuki, Taichi A; Nachman, Michael W

    2015-09-01

    In mammals, intrinsic postzygotic isolation has been well studied in males but has been less studied in females, despite the fact that female gametogenesis and pregnancy provide arenas for hybrid sterility or inviability that are absent in males. Here, we asked whether inviability or sterility is observed in female hybrids of Mus musculus domesticus and M. m. musculus, taxa which hybridize in nature and for which male sterility has been well characterized. We looked for parent-of-origin growth phenotypes by measuring adult body weights in F1 hybrids. We evaluated hybrid female fertility by crossing F1 females to a tester male and comparing multiple reproductive parameters between intrasubspecific controls and intersubspecific hybrids. Hybrid females showed no evidence of parent-of-origin overgrowth or undergrowth, providing no evidence for reduced viability. However, hybrid females had smaller litter sizes, reduced embryo survival, fewer ovulations, and fewer small follicles relative to controls. Significant variation in reproductive parameters was seen among different hybrid genotypes, suggesting that hybrid incompatibilities are polymorphic within subspecies. Differences in reproductive phenotypes in reciprocal genotypes were observed and are consistent with cyto-nuclear incompatibilities or incompatibilities involving genomic imprinting. These findings highlight the potential importance of reduced hybrid female fertility in the early stages of speciation. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  5. Editor's Highlight: Complete Attenuation of Mouse Lung Cell Proliferation and Tumorigenicity in CYP2F2 Knockout and CYP2F1 Humanized Mice Exposed to Inhaled Styrene for up to 2 Years Supports a Lack of Human Relevance.

    Science.gov (United States)

    Cruzan, George; Bus, James S; Banton, Marcy I; Sarang, Satinder S; Waites, Robbie; Layko, Debra B; Raymond, James; Dodd, Darol; Andersen, Melvin E

    2017-10-01

    Styrene is a mouse-specific lung carcinogen, and short-term mode of action studies have demonstrated that cytotoxicity and/or cell proliferation, and genomic changes are dependent on CYP2F2 metabolism. The current study examined histopathology, cell proliferation, and genomic changes in CD-1, C57BL/6 (WT), CYP2F2(-/-) (KO), and CYP2F2(-/-) (CYP2F1, 2B6, 2A13-transgene) (TG; humanized) mice following exposure for up to 104 weeks to 0- or 120-ppm styrene vapor. Five mice per treatment group were sacrificed at 1, 26, 52, and 78 weeks. Additional 50 mice per treatment group were followed until death or 104 weeks of exposure. Cytotoxicity was present in the terminal bronchioles of some CD-1 and WT mice exposed to styrene, but not in KO or TG mice. Hyperplasia in the terminal bronchioles was present in CD-1 and WT mice exposed to styrene, but not in KO or TG mice. Increased cell proliferation, measured by KI-67 staining, occurred in CD-1 and WT mice exposed to styrene for 1 week, but not after 26, 52, or 78 weeks, nor in KO or TG mice. Styrene increased the incidence of bronchioloalveolar adenomas and carcinomas in CD-1 mice. No increase in lung tumors was found in WT despite clear evidence of lung toxicity, or, KO or TG mice. The absence of preneoplastic lesions and tumorigenicity in KO and TG mice indicates that mouse-specific CYP2F2 metabolism is responsible for both the short-term and chronic toxicity and tumorigenicity of styrene, and activation of styrene by CYP2F2 is a rodent MOA that is neither quantitatively or qualitatively relevant to humans. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Activation of specific cellular immunity toward murine leukemia in mice rejecting syngeneic somatic hybrid cells

    International Nuclear Information System (INIS)

    Liang, W.; Cohen, E.P.

    1977-01-01

    ASL-1 x LM(TK) - somatic hybrid cells form both H-2/sup a/ and H-2/sup k/ antigen complexes. After forming a localized tumor in syngeneic (A/J x C 3 H/HeJ)F 1 mice, they are rejected. Such mice are resistant to otherwise invariably lethal injections of ASL-1 cells, surviving for prolonged and, in some instances, indefinite periods. To examine the basis of immunity, the capacity of spleen cells from mice rejecting hybrid cells to stimulate the release of 51 Cr from labeled ASL-1 cells was investigated. Cells from the spleens of mice rejecting ASL-1 x LM(TK) - cells stimulated the release of 51 Cr from labeled ASL-1 cells, but not from Ehrlich ascites or P815 cells. Cells from mice injected with mitomycin-C-treated ASL-1 cells led to the release of 51 Cr from labeled ASL-1 cells as well, but the extent of 51 Cr release was approximately one-third as occurred in the presence of cells from hybrid cell-injected mice. Cells from noninjected mice or from mice injected with LM(TK) - cells failed to lead to the specific release of 51 Cr from ASL-1 cells. The presence of unlabeled ASL-1 cells, but not Ehrlich ascites cells, competitively inhibited the spleen cell-stimulated release of 51 Cr from labeled ASL-1 cells. Sera from A/J mice injected with mitomycin-C-treated ASL-1 cells contained antibodies specific for the tumor-associated antigen of ASL-1 cells

  7. Regulatory divergence of X-linked genes and hybrid male sterility in mice.

    Science.gov (United States)

    Oka, Ayako; Shiroishi, Toshihiko

    2014-01-01

    Postzygotic reproductive isolation is the reduction of fertility or viability in hybrids between genetically diverged populations. One example of reproductive isolation, hybrid male sterility, may be caused by genetic incompatibility between diverged genetic factors in two distinct populations. Genetic factors involved in hybrid male sterility are disproportionately located on the X chromosome. Recent studies showing the evolutionary divergence in gene regulatory networks or epigenetic effects suggest that the genetic incompatibilities occur at much broader levels than had previously been thought (e.g., incompatibility of protein-protein interactions). The latest studies suggest that evolutionary divergence of transcriptional regulation causes genetic incompatibilities in hybrid animals, and that such incompatibilities preferentially involve X-linked genes. In this review, we focus on recent progress in understanding hybrid sterility in mice, including our studies, and we discuss the evolutionary significance of regulatory divergence for speciation.

  8. Asymmetry and polymorphism of hybrid male sterility during the early stages of speciation in house mice.

    Science.gov (United States)

    Good, Jeffrey M; Handel, Mary Ann; Nachman, Michael W

    2008-01-01

    House mice offer a powerful system for dissecting the genetic basis of phenotypes that isolate species in the early stages of speciation. We used a series of reciprocal crosses between wild-derived strains of Mus musculus and M. domesticus to examine F(1) hybrid male sterility, one of the primary phenotypes thought to isolate these species. We report four main results. First, we found significantly smaller testes and fewer sperm in hybrid male progeny of most crosses. Second, in some crosses hybrid male sterility was asymmetric and depended on the species origin of the X chromosome. These observations confirm and extend previous findings, underscoring the central role that the M. musculus X chromosome plays in reproductive isolation. Third, comparisons among reciprocal crosses revealed polymorphism at one or more hybrid incompatibilities within M. musculus. Fourth, the spermatogenic phenotype of this polymorphic interaction appears distinct from previously described hybrid incompatibilities between these species. These data build on previous studies of speciation in house mice and show that the genetic basis of hybrid male sterility is fairly complex, even at this early stage of divergence.

  9. Widespread over-expression of the X chromosome in sterile F₁hybrid mice.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Good

    2010-09-01

    Full Text Available The X chromosome often plays a central role in hybrid male sterility between species, but it is unclear if this reflects underlying regulatory incompatibilities. Here we combine phenotypic data with genome-wide expression data to directly associate aberrant expression patterns with hybrid male sterility between two species of mice. We used a reciprocal cross in which F₁ males are sterile in one direction and fertile in the other direction, allowing us to associate expression differences with sterility rather than with other hybrid phenotypes. We found evidence of extensive over-expression of the X chromosome during spermatogenesis in sterile but not in fertile F₁ hybrid males. Over-expression was most pronounced in genes that are normally expressed after meiosis, consistent with an X chromosome-wide disruption of expression during the later stages of spermatogenesis. This pattern was not a simple consequence of faster evolutionary divergence on the X chromosome, because X-linked expression was highly conserved between the two species. Thus, transcriptional regulation of the X chromosome during spermatogenesis appears particularly sensitive to evolutionary divergence between species. Overall, these data provide evidence for an underlying regulatory basis to reproductive isolation in house mice and underscore the importance of transcriptional regulation of the X chromosome to the evolution of hybrid male sterility.

  10. Widespread Over-Expression of the X Chromosome in Sterile F1 Hybrid Mice

    Science.gov (United States)

    Good, Jeffrey M.; Giger, Thomas; Dean, Matthew D.; Nachman, Michael W.

    2010-01-01

    The X chromosome often plays a central role in hybrid male sterility between species, but it is unclear if this reflects underlying regulatory incompatibilities. Here we combine phenotypic data with genome-wide expression data to directly associate aberrant expression patterns with hybrid male sterility between two species of mice. We used a reciprocal cross in which F1 males are sterile in one direction and fertile in the other direction, allowing us to associate expression differences with sterility rather than with other hybrid phenotypes. We found evidence of extensive over-expression of the X chromosome during spermatogenesis in sterile but not in fertile F1 hybrid males. Over-expression was most pronounced in genes that are normally expressed after meiosis, consistent with an X chromosome-wide disruption of expression during the later stages of spermatogenesis. This pattern was not a simple consequence of faster evolutionary divergence on the X chromosome, because X-linked expression was highly conserved between the two species. Thus, transcriptional regulation of the X chromosome during spermatogenesis appears particularly sensitive to evolutionary divergence between species. Overall, these data provide evidence for an underlying regulatory basis to reproductive isolation in house mice and underscore the importance of transcriptional regulation of the X chromosome to the evolution of hybrid male sterility. PMID:20941395

  11. Widespread over-expression of the X chromosome in sterile F₁hybrid mice.

    Science.gov (United States)

    Good, Jeffrey M; Giger, Thomas; Dean, Matthew D; Nachman, Michael W

    2010-09-30

    The X chromosome often plays a central role in hybrid male sterility between species, but it is unclear if this reflects underlying regulatory incompatibilities. Here we combine phenotypic data with genome-wide expression data to directly associate aberrant expression patterns with hybrid male sterility between two species of mice. We used a reciprocal cross in which F₁ males are sterile in one direction and fertile in the other direction, allowing us to associate expression differences with sterility rather than with other hybrid phenotypes. We found evidence of extensive over-expression of the X chromosome during spermatogenesis in sterile but not in fertile F₁ hybrid males. Over-expression was most pronounced in genes that are normally expressed after meiosis, consistent with an X chromosome-wide disruption of expression during the later stages of spermatogenesis. This pattern was not a simple consequence of faster evolutionary divergence on the X chromosome, because X-linked expression was highly conserved between the two species. Thus, transcriptional regulation of the X chromosome during spermatogenesis appears particularly sensitive to evolutionary divergence between species. Overall, these data provide evidence for an underlying regulatory basis to reproductive isolation in house mice and underscore the importance of transcriptional regulation of the X chromosome to the evolution of hybrid male sterility.

  12. Derivation of hybrid ES cell lines from two different strains of mice

    Directory of Open Access Journals (Sweden)

    Ho-Tak Lau

    2016-03-01

    Full Text Available Parental origin-dependent expression of the imprinted genes is essential for mammalian development. Zfp57 maintains genomic imprinting in mouse embryos and ES cells. To examine the allelic expression patterns of the imprinted genes in ES cells, we obtained multiple hybrid ES clones that were directly derived from the blastocysts generated from the cross between mice on two different genetic backgrounds. The blastocyst-derived ES clones displayed largely intact DNA methylation imprint at the tested imprinted regions. These hybrid ES clones will be useful for future studies to examine the allelic expression of the imprinted genes in ES cells and their differentiated progeny.

  13. Desempenho de populações híbridas F2 de arroz-vermelho (Oryza sativa) com arroz transgênico (O. sativa) resistente ao herbicida amonio-glufosinate Performance of F2 hybrid populations of red rice (Oryza sativa) with ammonium-glufosinate-resistant transgenic rice (O. sativa)

    OpenAIRE

    J.A. Noldin; S. Yokoyama; H. Stuker; F.T. Rampelotti; M.I.F. Gonçalves; D.S. Eberhardt; A. Abreu; P. Antunes; J. Vieira

    2004-01-01

    O arroz-vermelho e o arroz-preto constituem-se nas principais plantas daninhas infestantes da cultura de arroz irrigado, devido à dificuldade de controle seletivo desta espécie em lavouras comerciais. A utilização de cultivares geneticamente modificados resistentes a herbicidas não-seletivos constitui uma alternativa de controle do arroz-vermelho e arroz-preto em arroz irrigado. O objetivo deste trabalho foi avaliar o comportamento de populações híbridas F2 originárias do cruzamento entre o a...

  14. Beta-cell lines derived from transgenic mice expressing a hybrid insulin gene-oncogene

    DEFF Research Database (Denmark)

    Efrat, S; Linde, S; Kofod, Hans

    1988-01-01

    Three pancreatic beta-cell lines have been established from insulinomas derived from transgenic mice carrying a hybrid insulin-promoted simian virus 40 tumor antigen gene. The beta tumor cell (beta TC) lines maintain the features of differentiated beta cells for about 50 passages in culture. The ...... both to immortalize a rare cell type and to provide a selection for the maintenance of its differentiated phenotype....

  15. [Chromosomal localization of foreign genes in transgenic mice using dual-color fluorescence in situ hybridization].

    Science.gov (United States)

    Lin, Dan; Gong, Xiu-li; Li, Wei; Guo, Xin-bing; Zhu, Yi-wen; Huang, Ying

    2008-02-01

    To establish a highly sensitive and specific dual-color fluorescence in situ hybridization (D-FISH) method used for chromosomal localization of foreign genes in double transgenic mice. Two strains of double transgenic mice were used in this experiment, one was integrated with the herpes simplex virus thymidine kinase (HSV-tk) and the enhanced green fluorescence protein (eGFP), the other was with the short hairpin RNA interference(RNAi) and beta(654). Splenic cells cultured in vitro were arrested in metaphase by colchicine and hybridized with digoxigenin-labeled and biotinylated DNA probes, then detected by rhodamine-conjugated avidin and FITC-conjugated anti-digoxigenin. Dual-color fluorescence signals were detected on the same metaphase in both transgenic mice strains. In HSV-tk/eGFP double transgenic mice, strong green fluorescence for HSV-tk and red for eGFP were observed and localized at 2E5-G3 and 8A2-A4 respectively. In beta(654)/RNAi mice, beta(654) was detected as red fluorescence on chromosome 7D3-E2, and RNAi showed random integration on chromosomes. It was detected as green fluorescence on chromosome 12B1 in one mouse, while on 1E2.3-1F and 3A3 in the other. Highly sensitive and specific D-FISH method was established using the self-prepared DNA probes, and chromosomal localization of the foreign genes was also performed in combination with G-banding in double transgenic mice. This technology will facilitate the researches in transgenic animals and gene therapy models.

  16. Effects of leached components from a hybrid resin composite on the reproductive system of male mice

    Directory of Open Access Journals (Sweden)

    Taher Akbari Saeed

    2012-01-01

    Full Text Available Background and Aims: There is concern that leached components from dental composites may cause adverse changes in the reproductive health. This study aimed to assess the effects of leached components from a hybrid resin composite on the reproductive system of male mice.Materials and Methods: In the present animal study, twenty adult Syrian male mice were divided into two groups of 10 mice each. In the test group, components which leached from samples made from Filtek Z250 resin composite into 75% ethanol were daily administered to the mice for 28 days. In the control group, the procedure was repeated in the same way as the test group but without placing composite samples in the solution. Then, the body weight, weights of paired testes, Gonado Somatic Index, sperm viability, sperm motility, epididymal sperm reserve and daily sperm production were recorded. Four male mice in each group were mated with untreated female mice for 10 days. After that, the number of pregnant females and number of infants were recorded. The data were analyzed using repeated measures ANOVA, Chi-square test and t-test.Results: There was a significant reduction in the sperm viability and sperm motility of male mice in the test group compared to the control group (P=0.001. There was no any significant differences in other parameters between two groups (P>0.05.Conclusion: This study showed that the leached components from resin composites cannot cause infertility but they could potentially cause some adverse effects on the reproductive system of male mice.

  17. Polinomios perfectos sobre F2

    OpenAIRE

    Cely Rojas, Valeria

    2010-01-01

    Este trabajo muestra el status de los números perfectos y el análogo de los números perfectos en los anillos de polinomios. Además, se presentan las demostraciones de algunas propiedades de los polinomios perfectos sobre F2 de forma comprensible, basadas en el trabajo realizado por los profesores Luis Gallardo y Oliver Rahavandrainy. / Abstract. This work shows the status artis of perfect numbers and their analogue in the rings of polynomials. Proofs of some properties of perfect polynomials ...

  18. Re-engineering the zinc fingers of PRDM9 reverses hybrid sterility in mice.

    Science.gov (United States)

    Davies, Benjamin; Hatton, Edouard; Altemose, Nicolas; Hussin, Julie G; Pratto, Florencia; Zhang, Gang; Hinch, Anjali Gupta; Moralli, Daniela; Biggs, Daniel; Diaz, Rebeca; Preece, Chris; Li, Ran; Bitoun, Emmanuelle; Brick, Kevin; Green, Catherine M; Camerini-Otero, R Daniel; Myers, Simon R; Donnelly, Peter

    2016-02-11

    The DNA-binding protein PRDM9 directs positioning of the double-strand breaks (DSBs) that initiate meiotic recombination in mice and humans. Prdm9 is the only mammalian speciation gene yet identified and is responsible for sterility phenotypes in male hybrids of certain mouse subspecies. To investigate PRDM9 binding and its role in fertility and meiotic recombination, we humanized the DNA-binding domain of PRDM9 in C57BL/6 mice. This change repositions DSB hotspots and completely restores fertility in male hybrids. Here we show that alteration of one Prdm9 allele impacts the behaviour of DSBs controlled by the other allele at chromosome-wide scales. These effects correlate strongly with the degree to which each PRDM9 variant binds both homologues at the DSB sites it controls. Furthermore, higher genome-wide levels of such 'symmetric' PRDM9 binding associate with increasing fertility measures, and comparisons of individual hotspots suggest binding symmetry plays a downstream role in the recombination process. These findings reveal that subspecies-specific degradation of PRDM9 binding sites by meiotic drive, which steadily increases asymmetric PRDM9 binding, has impacts beyond simply changing hotspot positions, and strongly support a direct involvement in hybrid infertility. Because such meiotic drive occurs across mammals, PRDM9 may play a wider, yet transient, role in the early stages of speciation.

  19. The contribution of the Y chromosome to hybrid male sterility in house mice.

    Science.gov (United States)

    Campbell, Polly; Good, Jeffrey M; Dean, Matthew D; Tucker, Priscilla K; Nachman, Michael W

    2012-08-01

    Hybrid sterility in the heterogametic sex is a common feature of speciation in animals. In house mice, the contribution of the Mus musculus musculus X chromosome to hybrid male sterility is large. It is not known, however, whether F1 male sterility is caused by X-Y or X-autosome incompatibilities or a combination of both. We investigated the contribution of the M. musculus domesticus Y chromosome to hybrid male sterility in a cross between wild-derived strains in which males with a M. m. musculus X chromosome and M. m. domesticus Y chromosome are partially sterile, while males from the reciprocal cross are reproductively normal. We used eight X introgression lines to combine different X chromosome genotypes with different Y chromosomes on an F1 autosomal background, and we measured a suite of male reproductive traits. Reproductive deficits were observed in most F1 males, regardless of Y chromosome genotype. Nonetheless, we found evidence for a negative interaction between the M. m. domesticus Y and an interval on the M. m. musculus X that resulted in abnormal sperm morphology. Therefore, although F1 male sterility appears to be caused mainly by X-autosome incompatibilities, X-Y incompatibilities contribute to some aspects of sterility.

  20. Hidden Markov model analysis of maternal behavior patterns in inbred and reciprocal hybrid mice.

    Directory of Open Access Journals (Sweden)

    Valeria Carola

    Full Text Available Individual variation in maternal care in mammals shows a significant heritable component, with the maternal behavior of daughters resembling that of their mothers. In laboratory mice, genetically distinct inbred strains show stable differences in maternal care during the first postnatal week. Moreover, cross fostering and reciprocal breeding studies demonstrate that differences in maternal care between inbred strains persist in the absence of genetic differences, demonstrating a non-genetic or epigenetic contribution to maternal behavior. In this study we applied a mathematical tool, called hidden Markov model (HMM, to analyze the behavior of female mice in the presence of their young. The frequency of several maternal behaviors in mice has been previously described, including nursing/grooming pups and tending to the nest. However, the ordering, clustering, and transitions between these behaviors have not been systematically described and thus a global description of maternal behavior is lacking. Here we used HMM to describe maternal behavior patterns in two genetically distinct mouse strains, C57BL/6 and BALB/c, and their genetically identical reciprocal hybrid female offspring. HMM analysis is a powerful tool to identify patterns of events that cluster in time and to determine transitions between these clusters, or hidden states. For the HMM analysis we defined seven states: arched-backed nursing, blanket nursing, licking/grooming pups, grooming, activity, eating, and sleeping. By quantifying the frequency, duration, composition, and transition probabilities of these states we were able to describe the pattern of maternal behavior in mouse and identify aspects of these patterns that are under genetic and nongenetic inheritance. Differences in these patterns observed in the experimental groups (inbred and hybrid females were detected only after the application of HMM analysis whereas classical statistical methods and analyses were not able to

  1. Characterization and sequence analysis of the F2 promoter from corynephage BFK20

    International Nuclear Information System (INIS)

    Koptides, M.; Ugorcakova, J.; Baloghova, E.; Bukovska, G.; Timko, J.

    1994-01-01

    F2 promoter from corynephage BFK20 was isolated and characterized. It was functional in Escherichia coli and Corynebacterium glutamicum. Cloning of the F2 promoter into the pJUP05 promoter probe vector caused an increase of the neomycin phosphotransferase II specific activity. According to the Northern blot hybridization the nptII gene was expressed from the cloned F2 promoter. The apparent transcription start point in E. coli and C. glutamicum was determined. The-35 region of F2 promoter showed high similarity to that of E. coli promoter consensus sequence, but its - 10 region was G+C rich and had no significant homology to that. (author)

  2. X-y interactions underlie sperm head abnormality in hybrid male house mice.

    Science.gov (United States)

    Campbell, Polly; Nachman, Michael W

    2014-04-01

    The genetic basis of hybrid male sterility in house mice is complex, highly polygenic, and strongly X linked. Previous work suggested that there might be interactions between the Mus musculus musculus X and the M. m. domesticus Y with a large negative effect on sperm head morphology in hybrid males with an F1 autosomal background. To test this, we introgressed the M. m. domesticus Y onto a M. m. musculus background and measured the change in sperm morphology, testis weight, and sperm count across early backcross generations and in 11th generation backcross males in which the opportunity for X-autosome incompatibilities is effectively eliminated. We found that abnormality in sperm morphology persists in M. m. domesticus Y introgression males, and that this phenotype is rescued by M. m. domesticus introgressions on the X chromosome. In contrast, the severe reductions in testis weight and sperm count that characterize F1 males were eliminated after one generation of backcrossing. These results indicate that X-Y incompatibilities contribute specifically to sperm morphology. In contrast, X-autosome incompatibilities contribute to low testis weight, low sperm count, and sperm morphology. Restoration of normal testis weight and sperm count in first generation backcross males suggests that a small number of complex incompatibilities between loci on the M. m. musculus X and the M. m. domesticus autosomes underlie F1 male sterility. Together, these results provide insight into the genetic architecture of F1 male sterility and help to explain genome-wide patterns of introgression across the house mouse hybrid zone.

  3. The radiosensitivity of spermatogonial stem cells in C3H/101 F1 hybrid mice

    International Nuclear Information System (INIS)

    Van der Meer, Yvonne; De Rooij, Dirk G.; Cattanach, Bruce M.

    1993-01-01

    The radiosensitivity of spermatogonial stem cells of C3H/HeHx101/H F 1 hybrid mice was determined by counting undifferentiated spermatogonia at 10 days after X-irradiation. During the spermatogenic cycle, differences in radiosensitivity were found, which were correlated with the proliferative activity of the spermatogonial stem cells. In stage VIII irr , during quiescence, the spermatogonial stem cells were most radiosensitive with a D 0 of 1.4 Gy. In stages XI irr -V irr , when the cells were proliferatively active, the D 0 was about 2.6 Gy. Based on the D 0 values for sensitive and resistant spermatogonia and on the D 0 for the total population, a ratio of 45:55% of sensitive to resistant spermatogonial stem cells was estimated for cell killing. When the present data were compared with data on translocation induction obtained in mice of the same genotype, a close fit was obtained when the translocation yield (Y; in % abnormal cells) after a radiation dose D was described by Y=e τD , with τ=1 for the sensitive and τ=0.1 for the resistant spermatogonial stem cells, with a maximal e τD of 100

  4. Regulation of immune responses in SJL and F1 hybrid mice by gamma-irradiated syngeneic lymphoma cells

    International Nuclear Information System (INIS)

    Katz, I.R.; Nagase, F.; Bell, M.K.; Ponzio, N.M.; Thorbecke, G.J.

    1984-01-01

    Syngeneic mixed lymphocyte-stimulating la+ lymphomas of SJL mice [reticulum cell sarcoma(s) (RCS)] were found to modulate immune responses in vivo. Simultaneous injection of 2 X 10(7) gamma-irradiated or glutaraldehyde-fixed RCS cells with the antigen sheep red blood cells (SRBC) or 2,4,6-trinitrophenol (TNP)-Ficoll markedly suppressed the subsequent plaque-forming cell response in the spleen. The suppression of the anti-SRBC response was prevented by pretreatment of the mice with cyclophosphamide, whereas the suppression of the anti-TNP-Ficoll response was not affected. RCS injection induced high interferon serum titers within 24 hours after injection, which were not prevented by pretreatment with cyclophosphamide. Injection of gamma-irradiated RCS cells (gamma-RCS) or RCS cell extract 2 days prior to antigen enhanced the anti-SRBC but markedly suppressed the anti- TNP-Ficoll response. Injection of RCS both on day -2 and day 0 enhanced the anti-SRBC response. SJL mice 8-9 months of age showed much less or no suppression when gamma-RCS cells were injected on day 0. Certain F1 hybrids of SJL also showed the gamma-RCS-induced suppression of the anti-SRBC response. Suppression was seen in SJL X BALB.B but not in SJL X BALB/c mice and in SJL X A.TH but not in SJL X A.TL mice, suggesting an I-region effect. F1 hybrids of SJL by B10 background mice showed no significant suppression. Enhancement of the anti-SRBC response by prior injection of gamma-RCS was seen in all F1 hybrid mice examined

  5. Gonadal expression of aromatase and estrogen receptor alpha genes in two races of Tunisian mice and their hypofertile hybrids.

    Science.gov (United States)

    Saïd, Lamia; Delalande, Christelle; Britton-Davidian, Janice; Saïd, Khaled; Saad, Ali; Carreau, Serge

    2007-07-01

    House mice (Mus musculus domesticus) in Tunisia consists of two races, one carries the 40-acrocentric standard karyotypes and the other one is a robertsonian race (2n=22) homozygous for nine centric fusions (Rb). The F1 hybrids between the two chromosomal races showed a significant decrease in reproductive success and litter size. Such results can be related to the formation of meiotic trivalent in the hybrids leading to the production of viable aneuploid gametes and post-zygotic elimination of embryos due to chromosomal non disjunction events at meiosis. Moreover, testicular histology of F1 and backcross males showed in some cases a breakdown in spermatogenesis. In both females and males, androgens but also estrogens play an important role in gametogenesis. In this study, we have studied aromatase and estrogen receptor alpha (ERalpha) gene expression in the gonads of the two parental races and their chromosomal hybrids. The results showed that aromatase and ERalpha mRNAs are expressed in hybrid males of inter-racial crosses (female22Rb x male40Std and female40Std x male22Rb) and in hybrid females of inter-racial crosses (female22Rb x male40Std) as in the two parental races. However, in hybrid females of inter-racial crosses (female40Std x male22Rb) the amount of aromatase transcripts decreased sharply suggesting that this gene is involved in the breakdown of hybrid fertility in females, but not in males. However, in hybrid males, a putative post-translational modification of this enzyme, in terms of activity, should be verified.

  6. Hybridization change of DNA and nuclear RNA synthesized immediately after ionizing irradiation in spleen cells isolated from 615 mice

    International Nuclear Information System (INIS)

    Meng Ziqiang

    1986-01-01

    DNA hybridization with nuclear RNA(nRNA) synthesized immediately after 60 Co Gamma-irradiation in the spleen cells freshly isolated from inbred line 615 mice was investigated, using the technique of Gillespie and Spiegelman. In RNA/DNA hybridization percentage experiment, it was showed that the hybridization of normal DNA with labelled nRNA synthesized in irradiated cells reached the saturation point at a much faster rate than with labelled normal nRNA. The hybridization percentage of nRNA synthesized in irradiated cells was higher than that of normal nRNA during the different reaction time before the saturation point of DNA with nRNA synthesized in irradiated cells, but it was lower than that of normal nRNA after the zone of high repetitive DNA sequences was stimulated, however, the transcription of some base sequences in the zone of low repetitive DNA sequences was seriously inhibited. Measurements of the exhaustion rates of pulse-labelled nRNA were carried out as described by Greene and Flickinger Biochim. In these studies, pulse-labelled nRNA synthesized in unirradiated and irradiated cells were compared by exhausion with DNA at hybridization time of 4 or 24 hours, When the hybridization time was 4 hours, the nRNA synthesized in irradiated cells displayed a faster exhaustion rate than the control nRNA. But if the hybridization time was 24 hours, the exhaustion rate of nRNA synthesized in irradiated cells reduced. These results demostrated that Gamma-irradiation changed the proportion of transcription of some nRNA species and implayed that the sensitivities of the transcription activeties of the different repetitive DNA sequences to Gamma-irradiation were different, and so were the transcription activeties of the different base sequences in the same repetitive DNA sequences

  7. hmF2 variability over Havana

    International Nuclear Information System (INIS)

    Lazo, B.; Alazo, K.; Rodriguez, M.; Calzadilla, A.

    2003-01-01

    The hmF2 variability over Havana station (Geo. Latitude 23 deg. N, Geo Longitude 278 deg. E; Dip 54.6 deg. N; Modip: 44.8 deg. N) is presented. In this study different solar and seasonal conditions are considered. The results show that, in general, standard deviation of hmF2 is quite irregular and reaches its values at nighttimes hours. Lower and upper quartiles variability has a similar behaviour to IQ variability, showing its higher values at nighttimes too. (author)

  8. Chronic voluntary alcohol consumption results in tolerance to sedative/hypnotic and hypothermic effects of alcohol in hybrid mice

    Science.gov (United States)

    Ozburn, Angela Renee; Harris, R. Adron; Blednov, Yuri A.

    2013-01-01

    The continuous two bottle choice test is the most common measure of alcohol consumption but there is remarkably little information about the development of tolerance or dependence with this procedure. We showed that C57BL/6JxFVB/NJ and FVB/NJxC57BL/6J F1 hybrid mice demonstrate greater preference for and consumption of alcohol than either parental strain. In order to test the ability of this genetic model of high alcohol consumption to produce neuroadaptation, we examined development of alcohol tolerance and dependence after chronic self-administration using a continuous access two-bottle choice paradigm. Ethanol-experienced mice stably consumed about 16–18 g/kg/day of ethanol. Ethanol-induced withdrawal severity was assessed (after 59 days of drinking) by scoring handling-induced convulsions; withdrawal severity was minimal and did not differ between ethanol-experienced and -naïve mice. After 71 days of drinking, the rate of ethanol clearance was similar for ethanol-experienced and -naïve mice. After 77 days of drinking, ethanol-induced loss of righting reflex (LORR) was tested daily for 5 days. Ethanol-experienced mice had a shorter duration of LORR. For both ethanol-experienced and -naïve mice, blood ethanol concentrations taken at gain of righting reflex were greater on day 5 than on day 1, indicative of tolerance. After 98 days of drinking, ethanol-induced hypothermia was assessed daily for 3 days. Both ethanol-experienced and –naïve mice developed rapid and chronic tolerance to ethanol-induced hypothermia, with significant group differences on the first day of testing. In summary, chronic, high levels of alcohol consumption in F1 hybrid mice produced rapid and chronic tolerance to both the sedative/hypnotic and hypothermic effects of ethanol; additionally, a small degree of metabolic tolerance developed. The development of tolerance supports the validity of using this model of high alcohol consumption in genetic studies of alcoholism. PMID:23313769

  9. Reproductive Isolation in Hybrid Mice Due to Spermatogenesis Defects at Three Meiotic Stages

    OpenAIRE

    Oka, Ayako; Mita, Akihiko; Takada, Yuki; Koseki, Haruhiko; Shiroishi, Toshihiko

    2010-01-01

    Early in the process of speciation, reproductive failures occur in hybrid animals between genetically diverged populations. The sterile hybrid animals are often males in mammals and they exhibit spermatogenic disruptions, resulting in decreased number and/or malformation of mature sperms. Despite the generality of this phenomenon, comparative study of phenotypes in hybrid males from various crosses has not been done, and therefore the comprehensive genetic basis of the disruption is still elu...

  10. Phenotypic variation of F 1 and F 2 populations from three species of ...

    African Journals Online (AJOL)

    The incomplete restoration of some of the masked characters in the F2 hybrids suggests a near-complete homogenization of parental genomes and/or chromosomal disharmony through silent genomic changes. These might have prevented sufficient chromosomal rearrangement and full homology for improved vigour in ...

  11. Summary of breakout Session F2: F2, decision support systems: Knowledge systems

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The discussions in breakout session F2 are summarized. The topics discussed include contingency planning, environmental sensitivity, countermeasures planning tools, cleanup operations management, and logistics support systems. General comments, concerns and major research issues are summarized

  12. Dissecting the genetic architecture of F1 hybrid sterility in house mice.

    Science.gov (United States)

    Dzur-Gejdosova, Maria; Simecek, Petr; Gregorova, Sona; Bhattacharyya, Tanmoy; Forejt, Jiri

    2012-11-01

    Hybrid sterility as a postzygotic reproductive isolation mechanism has been studied for over 80 years, yet the first identifications of hybrid sterility genes in Drosophila and mouse are quite recent. To study the genetic architecture of F(1) hybrid sterility between young subspecies of house mouse Mus m. domesticus and M. m. musculus, we conducted QTL analysis of a backcross between inbred strains representing these two subspecies and probed the role of individual chromosomes in hybrid sterility using the intersubspecific chromosome substitution strains. We provide direct evidence that the asymmetry in male infertility between reciprocal crosses is conferred by the middle region of M. m. musculus Chr X, thus excluding other potential candidates such as Y, imprinted genes, and mitochondrial DNA. QTL analysis identified strong hybrid sterility loci on Chr 17 and Chr X and predicted a set of interchangeable autosomal loci, a subset of which is sufficient to activate the Dobzhansky-Muller incompatibility of the strong loci. Overall, our results indicate the oligogenic nature of F(1) hybrid sterility, which should be amenable to reconstruction by proper combination of chromosome substitution strains. Such a prefabricated model system should help to uncover the gene networks and molecular mechanisms underlying hybrid sterility. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  13. A complex genetic basis to X-linked hybrid male sterility between two species of house mice.

    Science.gov (United States)

    Good, Jeffrey M; Dean, Matthew D; Nachman, Michael W

    2008-08-01

    The X chromosome plays a central role in the evolution of reproductive isolation, but few studies have examined the genetic basis of X-linked incompatibilities during the early stages of speciation. We report the results of a large experiment focused on the reciprocal introgression of the X chromosome between two species of house mice, Mus musculus and M. domesticus. Introgression of the M. musculus X chromosome into a wild-derived M. domesticus genetic background produced male-limited sterility, qualitatively consistent with previous experiments using classic inbred strains to represent M. domesticus. The genetic basis of sterility involved a minimum of four X-linked factors. The phenotypic effects of major sterility QTL were largely additive and resulted in complete sterility when combined. No sterility factors were uncovered on the M. domesticus X chromosome. Overall, these results revealed a complex and asymmetric genetic basis to X-linked hybrid male sterility during the early stages of speciation in mice. Combined with data from previous studies, we identify one relatively narrow interval on the M. musculus X chromosome involved in hybrid male sterility. Only a handful of spermatogenic genes are within this region, including one of the most rapidly evolving genes on the mouse X chromosome.

  14. The behavior after intravenous injection in mice of multiwalled carbon nanotube / Fe3O4 hybrid MRI contrast agents.

    Science.gov (United States)

    Wu, Huixia; Liu, Gang; Zhuang, Yeming; Wu, Dongmei; Zhang, Haoqiang; Yang, Hong; Hu, He; Yang, Shiping

    2011-07-01

    Fe(3)O(4) nanoparticles were in situ loaded on the surface of multiwalled carbon nanotubes (MWCNTs) by a solvothermal method using diethylene glycol and diethanolamine as solvents and complexing agents. The as-prepared MWCNT/Fe(3)O(4) hybrids exhibited excellent hydrophilicity, superparamagnetic property at room temperature, and a high T(2) relaxivity of 175.5 mM(-1) s(-1) in aqueous solutions. In vitro experiments revealed that MWCNT/Fe(3)O(4) had an excellent magnetic resonance imaging (MRI) enhancement effect on cancer cells, and importantly, they displayed low cytotoxicity and neglectable hemolytic activity. After intravenous administration, the T(2)-weighted MRI signal in the liver and spleen of mice decreased significantly, suggesting the potential application of the hybrids as MRI contrast agents. The organ biodistribution studies, histological analyses and elimination investigations showed that the hybrids were uptaken by the liver, lung and spleen after intravenous injection, and could be excreted from the liver and kidney. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Study on the retention of enriched UO2F2 in the mouse and its radiogenotoxicological effects

    International Nuclear Information System (INIS)

    Hu Qiyue; Zhu Shoupeng

    1991-06-01

    The study on toxicological effects of enriched UO 2 F 2 was undertaken in purebred BALB/c male mice to examine: (a) the retention in body; (b) the testicular clearance; (c) the effect of sperm abnormality; (d) the effect of chromosomal aberrations in spermatogonia and primary spermatocytes; and (e) the effect of DNA damage in germ cells in various spermiogenic stages. Results show that enriched UO 2 F 2 mainly deposited in the kidneys, then the skeleton and liver. The amount of enriched UO 2 F 2 depositing in other tissues was small. Enriched UO 2 F 2 was similar to the natural uranium in transference and retention in the body. The testis had efficient clearance of enriched UO 2 F 2 . Enriched UO 2 F 2 could result in sperm abnormality. Even with the same treating does but at different treating time the rates of sperm abnormality were different. Enriched UO 2 F 2 could result in chromosomal aberrations in spermatogonia and primary spermatocytes. The important type of aberrations in spermatogonia was break. For primary spermatocytes the most significant aberration was multivalents. Enriched UO 2 F 2 could also result in DNA breakage in germ cells. The sensitivity of mouse germ cells at various stages to enriched UO 2 F 2 was different. There was a linear relationship between the amount of sperm DNA eluted and enriched UO 2 F 2 dose

  16. Modulation of Prdm9-controlled meiotic chromosome asynapsis overrides hybrid sterility in mice.

    Science.gov (United States)

    Gregorova, Sona; Gergelits, Vaclav; Chvatalova, Irena; Bhattacharyya, Tanmoy; Valiskova, Barbora; Fotopulosova, Vladana; Jansa, Petr; Wiatrowska, Diana; Forejt, Jiri

    2018-03-14

    Hybrid sterility is one of the reproductive isolation mechanisms leading to speciation. Prdm9 , the only known vertebrate hybrid-sterility gene, causes failure of meiotic chromosome synapsis and infertility in male hybrids that are the offspring of two mouse subspecies. Within species, Prdm9 determines the sites of programmed DNA double-strand breaks (DSBs) and meiotic recombination hotspots. To investigate the relation between Prdm9 -controlled meiotic arrest and asynapsis, we inserted random stretches of consubspecific homology on several autosomal pairs in sterile hybrids, and analyzed their ability to form synaptonemal complexes and to rescue male fertility. Twenty-seven or more megabases of consubspecific (belonging to the same subspecies) homology fully restored synapsis in a given autosomal pair, and we predicted that two or more DSBs within symmetric hotspots per chromosome are necessary for successful meiosis. We hypothesize that impaired recombination between evolutionarily diverged chromosomes could function as one of the mechanisms of hybrid sterility occurring in various sexually reproducing species. © 2018, Gregorova et al.

  17. Reproductive isolation in hybrid mice due to spermatogenesis defects at three meiotic stages.

    Science.gov (United States)

    Oka, Ayako; Mita, Akihiko; Takada, Yuki; Koseki, Haruhiko; Shiroishi, Toshihiko

    2010-09-01

    Early in the process of speciation, reproductive failures occur in hybrid animals between genetically diverged populations. The sterile hybrid animals are often males in mammals and they exhibit spermatogenic disruptions, resulting in decreased number and/or malformation of mature sperms. Despite the generality of this phenomenon, comparative study of phenotypes in hybrid males from various crosses has not been done, and therefore the comprehensive genetic basis of the disruption is still elusive. In this study, we characterized the spermatogenic phenotype especially during meiosis in four different cases of reproductive isolation: B6-ChrX(MSM), PGN-ChrX(MSM), (B6 × Mus musculus musculus-NJL/Ms) F(1), and (B6 × Mus spretus) F(1). The first two are consomic strains, both bearing the X chromosome of M. m. molossinus; in B6-ChrX(MSM), the genetic background is the laboratory strain C57BL/6J (predominantly M. m. domesticus), while in PGN-ChrX(MSM) the background is the PGN2/Ms strain purely derived from wild M. m. domesticus. The last two cases are F(1) hybrids between mouse subspecies or species. Each of the hybrid males exhibited cell-cycle arrest and/or apoptosis at either one or two of three distinct meiotic stages: premeiotic stage, zygotene-to-pachytene stage of prophase I, and metaphase I. This study shows that the sterility in hybrid males is caused by spermatogenic disruptions at multiple stages, suggesting that the responsible genes function in different cellular processes. Furthermore, the stages with disruptions are not correlated with the genetic distance between the respective parental strains.

  18. Radiation Effect on Body Weight and Hematological Changes of Hybrid Mice by Conventional Fraction, Large Abdominal Field Irradiation

    International Nuclear Information System (INIS)

    Lee, Sung Heon; Shin, Sei One; Kim, Myung Se

    1985-01-01

    Radiation effect on mammals, especially on hematologic changes, has been studied since discovery of x-ray. Various experimental animals were tried for radiobiological studies. 72 hybrid mice with conventional fraction (5X/week), large abdominal field (2 x 3cm, from symphysis pubic to xyphoid process) were used. Body weight was declined gradually by increasing irradiation doses, nadir was about 29.7% in male ; 30.4% in female at 6000 rad irradiation group. Hemoglobin value was nearly normal throughout entire treatment. Significant dropping of WBC count was noted to 40-50% of pretreatment values by only 1000 rad irradiation. Change of differential count was interesting; lymphocyte proportion showed gradual reduction, instead of gradual increasing of segmented neutrophil. Those proportion were reversed after 6000 rad irradiation. Urinary protein tests showed + - +++, showing no correlation with dosage. Application. of our study in clinical combination therapy (radiation + chemotherapy) was discussed

  19. Dissolution curve comparisons through the F(2) parameter, a Bayesian extension of the f(2) statistic.

    Science.gov (United States)

    Novick, Steven; Shen, Yan; Yang, Harry; Peterson, John; LeBlond, Dave; Altan, Stan

    2015-01-01

    Dissolution (or in vitro release) studies constitute an important aspect of pharmaceutical drug development. One important use of such studies is for justifying a biowaiver for post-approval changes which requires establishing equivalence between the new and old product. We propose a statistically rigorous modeling approach for this purpose based on the estimation of what we refer to as the F2 parameter, an extension of the commonly used f2 statistic. A Bayesian test procedure is proposed in relation to a set of composite hypotheses that capture the similarity requirement on the absolute mean differences between test and reference dissolution profiles. Several examples are provided to illustrate the application. Results of our simulation study comparing the performance of f2 and the proposed method show that our Bayesian approach is comparable to or in many cases superior to the f2 statistic as a decision rule. Further useful extensions of the method, such as the use of continuous-time dissolution modeling, are considered.

  20. Competitive proliferation in the hematopoietic tissues of irradiated hybrid mice engrafted with parental bone marrow and spleen

    International Nuclear Information System (INIS)

    Muramatsu, S.; Monnot, P.; Duplan, J.F.

    1976-01-01

    e kinetics of growth and differentiation of hematopoietic stem cells differ markedly according to their origin. A study of the ability of CFU from bone marrow (BM) or spleen to repopulate hemopoietic organs has been carried out in lethally irradiated mice restored with BM cells admixed with spleen cells bearing different chromosomal markers. Hemopoietic cells originating from AKR (40 acbrocentrics) and AKR/T1ALD (36 acrocentrics + 2 metacentrics) mice were engrafted into lethally irradiated (AKR x AKR/T1ALD)F1 or (C3H x AKR/T1ALD)F1 hybrid recipients. Within 10 days, the BM-derived elements outnumbered the spleen-derived population in BM and spleen. This held even when the number of injected spleen-CFU was twice that of BM-CFU. This difference of growth rate subsided within 20 days. The first cells to reappear in the thymus bore the recipient karyotype (endoregeneration); they were later replaced by BM-derived elements but spleen-derived cecells were never present in thymus in the case of competitive engraftment. In contrast, the lymph node cells bore the BM karyotype as well as the spleen karyotype. Injecting the spleen cells 3 days prior to the BM cells partially counterbalanced the overgrowth of the BM-derived elements in the BM and spleen but did not affect the thymic repopulation which remained strictly derived from BM-CFU. When mice were injected only with BM-CFU, or only with spleen-CFU, BM-derived cells were found in the thymus as early as 10-12 days after engraftment, whereas the spleen-derived cells did not appear in the thymus until days 18-20. (author)

  1. Dissecting the genetic architecture of F-1 hybrid sterility in house mice

    Czech Academy of Sciences Publication Activity Database

    Dzúr-Gejdošová, Mária; Šimeček, Petr; Gregorová, Soňa; Bhattacharyya, Tanmoy; Forejt, Jiří

    2012-01-01

    Roč. 66, č. 11 (2012), s. 3321-3335 ISSN 0014-3820 R&D Projects: GA MŠk(CZ) LD11079 Grant - others:AV ČR(CZ) Praemium Academiae Institutional research plan: CEZ:AV0Z50520514 Keywords : hybrid sterility * reproductive isolation * recombination hotspots * chromosome X * chromosome 17 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.864, year: 2012

  2. Meiotic sex chromosome inactivation is disrupted in sterile hybrid male house mice.

    Science.gov (United States)

    Campbell, Polly; Good, Jeffrey M; Nachman, Michael W

    2013-03-01

    In male mammals, the X and Y chromosomes are transcriptionally silenced in primary spermatocytes by meiotic sex chromosome inactivation (MSCI) and remain repressed for the duration of spermatogenesis. Here, we test the longstanding hypothesis that disrupted MSCI might contribute to the preferential sterility of heterogametic hybrid males. We studied a cross between wild-derived inbred strains of Mus musculus musculus and M. m. domesticus in which sterility is asymmetric: F1 males with a M. m. musculus mother are sterile or nearly so while F1 males with a M. m. domesticus mother are normal. In previous work, we discovered widespread overexpression of X-linked genes in the testes of sterile but not fertile F1 males. Here, we ask whether this overexpression is specifically a result of disrupted MSCI. To do this, we isolated cells from different stages of spermatogenesis and measured the expression of several genes using quantitative PCR. We found that X overexpression in sterile F1 primary spermatocytes is coincident with the onset of MSCI and persists in postmeiotic spermatids. Using a series of recombinant X genotypes, we then asked whether X overexpression in hybrids is controlled by cis-acting loci across the X chromosome. We found that it is not. Instead, one large interval in the proximal portion of the M. m. musculus X chromosome is associated with both overexpression and the severity of sterility phenotypes in hybrids. These results demonstrate a strong association between X-linked hybrid male sterility and disruption of MSCI and suggest that trans-acting loci on the X are important for the transcriptional regulation of the X chromosome during spermatogenesis.

  3. Scintillation properties of LiF–SrF2 and LiF–CaF2 eutectic

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Kawaguchi, Noriaki; Fujimoto, Yutaka; Fukuda, Kentaro; Watanabe, Kenichi; Yamazaki, Atsushi; Uritani, Akira

    2013-01-01

    Dopant free eutectic scintillators 6 LiF–SrF 2 and 6 LiF–CaF 2 were developed by the vertical Bridgeman method for the purpose of thermal neutron detection. The molar ratio of LiF and Ca/SrF 2 was 4:1 on its eutectic composition. The α-ray induced radioluminescence spectra of the scintillators showed intense emission peak at 300 nm due to the emission from the self-trapped exciton in Ca/SrF 2 layers. When the samples were irradiated with 252 Cf neutrons, 6 LiF–SrF 2 and 6 LiF–CaF 2 exhibited the light yields of 4700 and 9400 ph/n, respectively. Scintillation decay times of 6 LiF–SrF 2 and 6 LiF–CaF 2 were accepted for scintillation detectors, 90 and 250 ns, respectively. -- Highlights: • Nondoped LiF–CaF 2 and LiF–SrF 2 eutectic scinitillators are reported for the first time. • Two sample showed self-trapped exciton emission. • LiF–SrF 2 sample exhibited the light yield of 9400 ph/n and this value was comparable to conventional materials doped with rare earth ions. • Scintillation decay times of LiF–CaF 2 and LiF–SrF 2 were 250 and 90 ns, respectively

  4. Electron collisions with F2CO molecules

    Science.gov (United States)

    Freitas, Thiago Corrêa; Barbosa, Alessandra Souza; Bettega, Márcio Henrique Franco

    2017-07-01

    In this paper we present elastic differential, integral, and momentum-transfer cross sections for electron collisions with carbonyl fluoride (F2CO ) molecules for the incident electron's energy from 0.5 eV to 20 eV. The Schwinger multichannel method with pseudopotentials was employed to obtain the cross sections in the static-exchange and static-exchange plus polarization approximations. The present results were compared with the available data in the literature, in particular, with the results of Kaur, Mason, and Antony [Phys. Rev. A 92, 052702 (2015), 10.1103/PhysRevA.92.052702] for the differential, total, and momentum-transfer cross sections. We have found a π* shape resonance centered at 2.6 eV in the B1 symmetry and other resonance, in the B2 symmetry, located at around 9.7 eV. A systematic study of the inclusion of polarization effects was performed in order to have a well balanced description of this negative-ion transient state. The effects of the long-range electric dipole potential were included by the Born closure scheme. Electronic structure calculations were also performed to help in the interpretation of the scattering results, and associate the transient states to the unoccupied orbitals.

  5. Pou4f2 knock-in Cre mouse: A multifaceted genetic tool for vision researchers.

    Science.gov (United States)

    Simmons, Aaron B; Bloomsburg, Samuel J; Billingslea, Samuel A; Merrill, Morgan M; Li, Shuai; Thomas, Marshall W; Fuerst, Peter G

    2016-01-01

    A transgenic mouse that expresses Cre recombinase under control of the Pou4f2-promoter (also referred to as Brn-3b and Brn-3.2) was characterized. Pou4f2 expression has been reported in a subset of retinal ganglion cells (RGCs) in the retina, in the midbrain, and in the germline. In this study, we characterize the expression pattern of this Cre-recombinase line and report its utility in targeted deletion, temporal deletion, RGC depletion, and germline targeting, which can be regulated by the sex of the Cre-carrying mouse. Pou4f2(Cre) was mapped by using a combination of PCR and sequencing of PCR products to better understand the construct and to locate where it was inserted within the Pou4f2 locus. Cre expression patterns were examined by crossing Pou4f2(Cre/+) mice to Cre reporter mice. Immunohistochemistry was used to further define the pattern of Cre expression and Cre-mediated recombination within the retina, brain, and other tissues. An internal ribosome entry site (IRES)-Cre cassette was inserted into the Pou4f2 gene disrupting normal gene function, as verified by the depletion of RGCs in mice homozygous for the insert. Pou4f2(Cre) expression was observed in the retina, brain, peripheral neurons, and male germ cells. Germline recombination was observed when the sire carried the Cre and the target for recombination. In all other breeding schemes, recombination was observed within subsets of cells within the retina, brain, intestines, heart, and gonads. In the retina, Cre efficiently targets recombination in neurons within the RGC layer (RGL), the inner nuclear layer (INL), and a small percentage of photoreceptors, activity that has not been previously reported. Unlike most other Cre lines active in the inner retina, recombination in Müller and other glia was not observed in mice carrying Pou4f2(Cre) . Within the visual centers of the brain, Cre targets recombination in about 15% of cells within the superchiasmatic nucleus, lateral geniculate nucleus, and

  6. Comparison of ionospheric F2 peak parameters foF2 and hmF2 with IRI2001 at Hainan

    Science.gov (United States)

    Wang, X.; Shi, J. K.; Wang, G. J.; Gong, Y.

    2009-06-01

    Monthly median values of foF2, hmF2 and M(3000)F2 parameters, with quarter-hourly time interval resolution for the diurnal variation, obtained with DPS4 digisonde at Hainan (19.5°N, 109.1°E; Geomagnetic coordinates: 178.95°E, 8.1°N) are used to investigate the low-latitude ionospheric variations and comparisons with the International Reference Ionosphere (IRI) model predictions. The data used for the present study covers the period from February 2002 to April 2007, which is characterized by a wide range of solar activity, ranging from high solar activity (2002) to low solar activity (2007). The results show that (1) Generally, IRI predictions follow well the diurnal and seasonal variation patterns of the experimental values of foF2, especially in the summer of 2002. However, there are systematic deviation between experimental values and IRI predictions with either CCIR or URSI coefficients. Generally IRI model greatly underestimate the values of foF2 from about noon to sunrise of next day, especially in the afternoon, and slightly overestimate them from sunrise to about noon. It seems that there are bigger deviations between IRI Model predictions and the experimental observations for the moderate solar activity. (2) Generally the IRI-predicted hmF2 values using CCIR M(3000)F2 option shows a poor agreement with the experimental results, but there is a relatively good agreement in summer at low solar activity. The deviation between the IRI-predicted hmF2 using CCIR M(3000)F2 and observed hmF2 is bigger from noon to sunset and around sunrise especially at high solar activity. The occurrence time of hmF2 peak (about 1200 LT) of the IRI model predictions is earlier than that of observations (around 1500 LT). The agreement between the IRI hmF2 obtained with the measured M(3000)F2 and the observed hmF2 is very good except that IRI overestimates slightly hmF2 in the daytime in summer at high solar activity and underestimates it in the nighttime with lower values near

  7. Genomic networks of hybrid sterility.

    Directory of Open Access Journals (Sweden)

    Leslie M Turner

    2014-02-01

    Full Text Available Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities". The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL. Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is

  8. Genomic networks of hybrid sterility.

    Science.gov (United States)

    Turner, Leslie M; White, Michael A; Tautz, Diethard; Payseur, Bret A

    2014-02-01

    Hybrid dysfunction, a common feature of reproductive barriers between species, is often caused by negative epistasis between loci ("Dobzhansky-Muller incompatibilities"). The nature and complexity of hybrid incompatibilities remain poorly understood because identifying interacting loci that affect complex phenotypes is difficult. With subspecies in the early stages of speciation, an array of genetic tools, and detailed knowledge of reproductive biology, house mice (Mus musculus) provide a model system for dissecting hybrid incompatibilities. Male hybrids between M. musculus subspecies often show reduced fertility. Previous studies identified loci and several X chromosome-autosome interactions that contribute to sterility. To characterize the genetic basis of hybrid sterility in detail, we used a systems genetics approach, integrating mapping of gene expression traits with sterility phenotypes and QTL. We measured genome-wide testis expression in 305 male F2s from a cross between wild-derived inbred strains of M. musculus musculus and M. m. domesticus. We identified several thousand cis- and trans-acting QTL contributing to expression variation (eQTL). Many trans eQTL cluster into eleven 'hotspots,' seven of which co-localize with QTL for sterility phenotypes identified in the cross. The number and clustering of trans eQTL-but not cis eQTL-were substantially lower when mapping was restricted to a 'fertile' subset of mice, providing evidence that trans eQTL hotspots are related to sterility. Functional annotation of transcripts with eQTL provides insights into the biological processes disrupted by sterility loci and guides prioritization of candidate genes. Using a conditional mapping approach, we identified eQTL dependent on interactions between loci, revealing a complex system of epistasis. Our results illuminate established patterns, including the role of the X chromosome in hybrid sterility. The integrated mapping approach we employed is applicable in a broad

  9. Radiobiological properties of spermatogonial stem cells in C3H/101 hybrid mice and evaluation of the model for induction of genetic damage in spermatogonial stem cells

    International Nuclear Information System (INIS)

    De Rooij, V.

    1993-01-01

    C3H/101 (3H1) hybrid mice are studied, in order to find answers to the following questions: What are the D 0 values for killing of proliferating and quiescent stem cells by X-irradiation in 3H1 mice; How many stem cells are present per 3H1 testis and what is the density of these cells during the epithelial cycle; What are the approximate numbers of proliferating and quiescent stem cells in a 3H1 mouse testis. (R.P.) 5 figs

  10. Comparison of global brain gene expression profiles between inbred long-sleep and inbred short-sleep mice by high-density gene array hybridization.

    Science.gov (United States)

    Xu, Y; Ehringer, M; Yang, F; Sikela, J M

    2001-06-01

    Inbred long-sleep (ILS) and short-sleep (ISS) mice show significant central nervous system-mediated differences in sleep time for sedative dose of ethanol and are frequently used as a rodent model for ethanol sensitivity. In this study, we have used complementary DNA (cDNA) array hybridization methodology to identify genes that are differentially expressed between the brains of ILS and ISS mice. To carry out this analysis, we used both the gene discovery array (GDA) and the Mouse GEM 1 Microarray. GDA consists of 18,378 nonredundant mouse cDNA clones on a single nylon filter. Complex probes were prepared from total brain mRNA of ILS or ISS mice by using reverse transcription and 33P labeling. The labeled probes were hybridized in parallel to the gene array filters. Data from GDA experiments were analyzed with SQL-Plus and Oracle 8. The GEM microarray includes 8,730 sequence-verified clones on a glass chip. Two fluorescently labeled probes were used to hybridize a microarray simultaneously. Data from GEM experiments were analyzed by using the GEMTools software package (Incyte). Differentially expressed genes identified from each method were confirmed by relative quantitative reverse transcription-polymerase chain reaction (RT-PCR). A total of 41 genes or expressed sequence tags (ESTs) display significant expression level differences between brains of ILS and ISS mice after GDA, GEM1 hybridization, and quantitative RT-PCR confirmation. Among them, 18 clones were expressed higher in ILS mice, and 23 clones were expressed higher in ISS mice. The individual gene or EST's function and mapping information have been analyzed. This study identified 41 genes that are differentially expressed between brains of ILS and ISS mice. Some of them may have biological relevance in mediation of phenotypic variation between ILS and ISS mice for ethanol sensitivity. This study also demonstrates that parallel gene expression comparison with high-density cDNA arrays is a rapid and

  11. Magnetic hyperfine interactions of U2 center in CaF2, SrF2 and BaF2

    International Nuclear Information System (INIS)

    Graf, C.J.F.

    1976-02-01

    The magnetic hyperfine parameters of the U 2 center in CaF 2 , SeF 2 and BaF 2 , using a molecular orbitals scheme have been calculated. The need for the inclusion of mechanisms such as Pauli Repulsion and Covalence in order to describe the electronic structure of the defect has been shown. In the molecular orbitals model a weak covalence parameter has been phenomenologically introduced, mixing the is atomic wavefunction of hydrogen with a properly symmetrized linear combination of 2p F - functions centered on the ions of the first fluorine shell. The results obtained are compared with experimental measurements of EPR and ENDOR. (Author) [pt

  12. Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae.

    Science.gov (United States)

    Nag, D; Koley, H; Sinha, R; Mukherjee, P; Sarkar, C; Withey, J H; Gachhui, R

    2016-02-01

    An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future. © 2015 The Foundation for the Scandinavian Journal of Immunology.

  13. Calculation of the hyperfine constants of Vk center in CaF2, SrF2 and BaF2

    International Nuclear Information System (INIS)

    Bufaical, R.F.

    1975-03-01

    The magnetic hyperfine constants of the V sub(K) center in CaF 2 , SrF 2 and BaF 2 have been calculated, assuming a phenomenological model, based on the F 2 central molecule, to describe the wave function of the defect. The introduction of covalence, with the ions neighboring the central molecule, have shown that this is a better description for the defect than a simple central molecule model. It was also shown that the results for the hyperfine constants are strongly dependent on the relaxations of these neighboring ions, which have been determined by fitting the experimental data. The present results are compared with other previous calculations where similar and different methods have been used. A better description for the wave function of the defect is suggested

  14. Calculation of the hyperfine constants of the V sub (K) center in CaF2, SrF2 e BaF2

    International Nuclear Information System (INIS)

    Bufaical, R.F.

    1975-03-01

    The magnetic hyperfine constants of the V sub(K) center in CaF 2 , SrF 2 and BaF 2 have been calculated, assuming a phenomenological model, based on the F - 2 'central molecule', to describe the wave function of the defect. The introduction of covalence with the ions neighboring the 'central molecule', has shown that this is a better description for the defect than a simple 'central molecule' model. It was also shown that the results for the hyperfine constants are strongly dependent on the relaxations of these neighboring ions, which have been determined by fitting the experimental data. The present results are compared with other previous calculations where similar and different methods have been used. A better description for the wave function of the defect is suggested. (author) [pt

  15. Chronic self-administration of alcohol results in elevated ΔFosB: comparison of hybrid mice with distinct drinking patterns

    Directory of Open Access Journals (Sweden)

    Ozburn Angela R

    2012-10-01

    Full Text Available Abstract Background The inability to reduce or regulate alcohol intake is a hallmark symptom for alcohol use disorders. Research on novel behavioral and genetic models of experience-induced changes in drinking will further our knowledge on alcohol use disorders. Distinct alcohol self-administration behaviors were previously observed when comparing two F1 hybrid strains of mice: C57BL/6J x NZB/B1NJ (BxN show reduced alcohol preference after experience with high concentrations of alcohol and periods of abstinence while C57BL/6J x FVB/NJ (BxF show sustained alcohol preference. These phenotypes are interesting because these hybrids demonstrate the occurrence of genetic additivity (BxN and overdominance (BxF in ethanol intake in an experience dependent manner. Specifically, BxF exhibit sustained alcohol preference and BxN exhibit reduced alcohol preference after experience with high ethanol concentrations; however, experience with low ethanol concentrations produce sustained alcohol preference for both hybrids. In the present study, we tested the hypothesis that these phenotypes are represented by differential production of the inducible transcription factor, ΔFosB, in reward, aversion, and stress related brain regions. Results Changes in neuronal plasticity (as measured by ΔFosB levels were experience dependent, as well as brain region and genotype specific, further supporting that neuronal circuitry underlies motivational aspects of ethanol consumption. BxN mice exhibiting reduced alcohol preference had lower ΔFosB levels in the Edinger-Westphal nucleus than mice exhibiting sustained alcohol preference, and increased ΔFosB levels in central medial amygdala as compared with control mice. BxN mice showing sustained alcohol preference exhibited higher ΔFosB levels in the ventral tegmental area, Edinger-Westphal nucleus, and amygdala (central and lateral divisions. Moreover, in BxN mice ΔFosB levels in the Edinger-Westphal nucleus and ventral

  16. Difluorophosphoryl nitrene F2P(O)N: matrix isolation and unexpected rearrangement to F2PNO.

    Science.gov (United States)

    Zeng, Xiaoqing; Beckers, Helmut; Willner, Helge; Neuhaus, Patrik; Grote, Dirk; Sander, Wolfram

    2009-12-14

    Triplet difluorophosphoryl nitrene F(2)P(O)N (X(3)A'') was generated on ArF excimer laser irradiation (lambda=193 nm) of F(2)P(O)N(3) in solid argon matrix at 16 K, and characterized by its matrix IR, UV/Vis, and EPR spectra, in combination with DFT and CBS-QB3 calculations. On visible light irradiation (lambda>420 nm) at 16 K F(2)P(O)N reacts with molecular nitrogen and some of the azide is regenerated. UV irradiation (lambda=255 nm) of F(2)P(O)N (X(3)A'') induced a Curtius-type rearrangement, but instead of a 1,3-fluorine shift, nitrogen migration to give F(2)PON is proposed to be the first step of the photoisomerization of F(2)P(O)N into F(2)PNO (difluoronitrosophosphine). Formation of novel F(2)PNO was confirmed with (15)N- and (18)O-enriched isotopomers by IR spectroscopy and DFT calculations. Theoretical calculations predict a rather long P-N bond of 1.922 A [B3LYP/6-311+G(3df)] and low bond-dissociation energy of 76.3 kJ mol(-1) (CBS-QB3) for F(2)PNO.

  17. Cooled optically stimulated luminescence in CaF2:Mn

    International Nuclear Information System (INIS)

    Miller, S.D.; Endres, G.W.R.; McDonald, J.C.; Swinth, K.L.

    1988-01-01

    A new optically stimulated luminescence technique has been developed for the readout of CaF 2 :Mn thermoluminescent material. Minimum detectable gamma exposures may potentially be measured at 10 nC.kg -1 using the 254 nm line of a mercury lamp. Additional studies were done on CaF 2 :Mn using 351 nm excimer laser stimulation. (author)

  18. Contrasting behavior of heterochromatic and euchromatic chromosome portions and pericentric genome separation in pre-bouquet spermatocytes of hybrid mice.

    Science.gov (United States)

    Scherthan, Harry; Schöfisch, Karina; Dell, Thomas; Illner, Doris

    2014-12-01

    The spatial distribution of parental genomes has attracted much interest because intranuclear chromosome distribution can modulate the transcriptome of cells and influence the efficacy of meiotic homologue pairing. Pairing of parental chromosomes is imperative to sexual reproduction as it translates into homologue segregation and genome haploidization to counteract the genome doubling at fertilization. Differential FISH tagging of parental pericentromeric genome portions and specific painting of euchromatic chromosome arms in Mus musculus (MMU) × Mus spretus (MSP) hybrid spermatogenesis disclosed a phase of homotypic non-homologous pericentromere clustering that led to parental pericentric genome separation from the pre-leptoteneup to zygotene stages. Preferential clustering of MMU pericentromeres correlated with particular enrichment of epigenetic marks (H3K9me3), HP1-γ and structural maintenance of chromosomes SMC6 complex proteins at the MMU major satellite DNA repeats. In contrast to the separation of heterochromatic pericentric genome portions, the euchromatic arms of homeologous chromosomes showed considerable presynaptic pairing already during leptotene stage of all mice investigated. Pericentric genome separation was eventually disbanded by telomere clustering that concentrated both parental pericentric genome portions in a limited nuclear sector of the bouquet nucleus. Our data disclose the differential behavior of pericentromeric heterochromatin and the euchromatic portions of the parental genomes during homologue search. Homotypic pericentromere clustering early in prophase I may contribute to the exclusion of large repetitive DNA domains from homology search, while the telomere bouquet congregates and registers spatially separated portions of the genome to fuel synapsis initiation and high levels of homologue pairing, thus contributing to the fidelity of meiosis and reproduction.

  19. Semiconductor CdF2:Ga and CdF2:In Crystals as Media for Real-Time Holography

    Science.gov (United States)

    Ryskin, Alexander I.; Shcheulin, Alexander S.; Angervaks, Alexander E.

    2012-01-01

    Monocrystalline cadmium fluoride is a dielectric solid that can be converted into a semiconductor by doping with donor impurities and subsequent heating in the reduction atmosphere. For two donor elements, Ga and In, the donor (“shallow”) state is a metastable one separated from the ground (“deep”) state by a barrier. Photoinduced deep-to-shallow state transition underlies the photochromism of CdF2:Ga and CdF2:In. Real-time phase holograms are recorded in these crystals capable of following up optical processes in a wide frequency range. The features of photochromic transformations in CdF2:Ga and CdF2:In crystals as well as holographic characteristics of these media are discussed. Exemplary applications of CdF2-based holographic elements are given. PMID:28817009

  20. Shock Compression Response of Calcium Fluoride (CaF2)

    Science.gov (United States)

    Root, Seth

    2017-06-01

    The fluorite crystal structure is a textbook lattice that is observed for many systems, such as CaF2, Mg2 Si, and CeO2. Specifically, CaF2 is a useful material for studying the fluorite system because it is readily available as a single crystal. Under static compression, CaF2 is known to have at least three solid phases: fluorite, cotunnite, and a Ni2 In phase. Along the Hugoniot CaF2 undergoes a fluorite to cotunnite phase transition, however, at higher shock pressures it is unknown whether CaF2 undergoes another solid phase transition or melts directly from the cotunnite phase. In this work, we conducted planar shock compression experiments on CaF2 using Sandia's Z-machine and a two-stage light gun up to 900 GPa. In addition, we use density functional theory (DFT) based quantum molecular dynamics (QMD) simulations to provide insight into the CaF2 state along the Hugoniot. In collaboration with: Michael Desjarlais, Ray Lemke, Patricia Kalita, Scott Alexander, Sandia National Laboratories. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL850.

  1. Scintillation properties of CdF2 crystal

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Fujimoto, Yutaka; Koshimizu, Masanori; Fukuda, Kentaro

    2015-01-01

    CdF 2 single crystal was prepared by Tokuyama Corp. with the μ-PD method to investigate Auger free luminescence of this material. From optical transmittance spectrum, bandgap wavelength was around 280 nm. In X-ray induced radioluminescence spectrum, emission lines appeared around 350 nm and 420 nm. Excitation wavelength was investigated and excitation peak was around 250 nm. Photoluminescence and scintillation decay times were evaluated and decay time was few ns. Temperature dependence of X-ray induced radioluminescence was compared with conventional BaF 2 scintillator and scintillation of CdF 2 decreased when the temperature increased. Consequently, scintillation of CdF 2 is possibly emission at color centers or exciton related one. - Highlights: • CdF 2 crystal scinitillator was synthesized. • Emission wavelengths of CdF 2 appeared around 350 and 420 nm. • Scintillation decay time of CdF 2 was quite fast, 1.75 ns. • Excitation bands were investigated by using Synchrotron facility, UVSOR

  2. Molecular CsF 5 and CsF 2 +

    KAUST Repository

    Rogachev, Andrey Yu.; Miao, Mao-sheng; Merino, Gabriel; Hoffmann, Roald

    2015-01-01

    D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  3. Molecular CsF 5 and CsF 2 +

    KAUST Repository

    Rogachev, Andrey Yu.

    2015-06-03

    D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  4. Substituting mouse transcription factor Pou4f2 with a sea urchin orthologue restores retinal ganglion cell development.

    Science.gov (United States)

    Mao, Chai-An; Agca, Cavit; Mocko-Strand, Julie A; Wang, Jing; Ullrich-Lüter, Esther; Pan, Ping; Wang, Steven W; Arnone, Maria Ina; Frishman, Laura J; Klein, William H

    2016-03-16

    Pou domain transcription factor Pou4f2 is essential for the development of retinal ganglion cells (RGCs) in the vertebrate retina. A distant orthologue of Pou4f2 exists in the genome of the sea urchin (class Echinoidea) Strongylocentrotus purpuratus (SpPou4f1/2), yet the photosensory structure of sea urchins is strikingly different from that of the mammalian retina. Sea urchins have no obvious eyes, but have photoreceptors clustered around their tube feet disc. The mechanisms that are associated with the development and function of photoreception in sea urchins are largely unexplored. As an initial approach to better understand the sea urchin photosensory structure and relate it to the mammalian retina, we asked whether SpPou4f1/2 could support RGC development in the absence of Pou4f2. To answer this question, we replaced genomic Pou4f2 with an SpPou4f1/2 cDNA. In Pou4f2-null mice, retinas expressing SpPou4f1/2 were outwardly identical to those of wild-type mice. SpPou4f1/2 retinas exhibited dark-adapted electroretinogram scotopic threshold responses, indicating functionally active RGCs. During retinal development, SpPou4f1/2 activated RGC-specific genes and in S. purpuratus, SpPou4f2 was expressed in photoreceptor cells of tube feet in a pattern distinct from Opsin4 and Pax6. Our results suggest that SpPou4f1/2 and Pou4f2 share conserved components of a gene network for photosensory development and they maintain their conserved intrinsic functions despite vast morphological differences in mouse and sea urchin photosensory structures. © 2016 The Authors.

  5. Hemispherical F2-layer differences and the neutral atmosphere

    International Nuclear Information System (INIS)

    Kotadia, K.M.; Almaula, N.R.

    1978-01-01

    A study is made of noon and early morning (05 h) critical frequencies of the F2-layer through one solar cycle (1958-1969) at 8 pairs of dip-conjugate stations at latitudes lower than +- 60 0 dip. The study reveals some characteristic features of the F2-layer, such as (1) at sunspot minimum the noon foF2 values exhibit a marked semiannual variation with equinoxial maxima in the north and a dominant annual variation with a maximum in December in the south; (2) the annual component of the foF2 variation increases appreciably with solar activity in the north, while the semiannual component increases in the south. They show maxima at latitudes near +- 40 0 dip and minima near the equator. The early morning foF2 values essentially go through an annual wave with maxima in local summer in both hemispheres; there is, however, a significant semiannual component in the south. The annual component is largest at +- 40 0 dip while the semiannual component has peaks at the equator and at 40 0 S dip. The differences between the behaviour of foF2 in the two hemispheres as reported in this paper appear to be in conformity with current thinking on the effects of (a) the global neutral wind pattern and (b) changes in the relative proportions of atomic and molecular gas species. (author)

  6. Urinary F2-Isoprostanes and Metabolic Markers of Fat Oxidation

    Directory of Open Access Journals (Sweden)

    Dora Il’yasova

    2015-01-01

    Full Text Available Metabolomic studies of increased fat oxidation showed increase in circulating acylcarnitines C2, C8, C10, and C12 and decrease in C3, C4, and C5. We hypothesize that urinary F2-isoprostanes reflect intensity of fatty acid oxidation and are associated with circulating C2, C8, C10, and C12 directly and with C3, C4, and C5 inversely. Four urinary F2-isoprostane isomers and serum acylcarnitines are quantified using LC-MS/MS within the Insulin Resistance Atherosclerosis Study nondiabetic cohort (n = 682. Cross-sectional associations between fasting urinary F2-isoprostanes (summarized as a composite index and the selected acylcarnitines are examined using generalized linear models. F2-isoprostane index is associated with C2 and C12 directly and with C5 inversely: the adjusted beta coefficients are 0.109, 0.072, and −0.094, respectively (P < 0.05. For these acylcarnitines and for F2-isoprostanes, the adjusted odds ratios (ORs of incident diabetes are calculated from logistic regression models: the ORs (95% CI are 0.77 (0.60–0.97, 0.79 (0.62–1.01, 1.18 (0.92–1.53, and 0.51 (0.35–0.76 for C2, C12, C5, and F2-isoprostanes, respectively. The direction of the associations between urinary F2-isoprostanes and three acylcarnitines (C2, C5, and C12 supports our hypothesis. The inverse associations of C2 and C12 and with incident diabetes are consistent with the suggested protective role of efficient fat oxidation.

  7. Studies of radioinduced mutations in sorghum grain: 1. Comparison of phenotypic variability obtained through hybridation and mutagenesis of F2 and M2 populations; 2. Agronomical and physiotechnical characterization of mutants lines in the original collection and in the advanced lines of the Chapingo Postgraduate college

    International Nuclear Information System (INIS)

    Parra Negrete, L.A.

    1986-01-01

    Genetic inprovement of cultivated plants consists essentially of three phases (1) generation of genetic variability (2) selection of genotypes and (3) evaluation of selected genotypes. Hybridization and spontaneous or induced mutations are, responsible for the generation of and increase in genetic vegetative variability. Accordingly, such methods are used alternatively in local programs for plant improvement either for introducing improved genotypes or as sources of germplasma. This thesis is based on two experiments of mutations induced by cobalt 60 ionizing radiation while using distinct materials and methods presented in two parts, the first section analyze the mutation variability and the second the evaluation of mutant lines. (author)

  8. Hybrid mimics and hybrid vigor in Arabidopsis

    Science.gov (United States)

    Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

    2015-01-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378

  9. Electron color centers in SrF2-Na crystals

    International Nuclear Information System (INIS)

    Kachan, S.I.; Chornij, Z.P.

    2006-01-01

    A radiation-induced memory effect in SrF 2 -Na crystals is studied. It was shown that optical bleaching of M + A color centers at 80 K in SrF 2 -Na crystals causes the core of an M + A -center to transform into the V + a Me + V + a configuration, in which all three point defects are arranged diagonally in the cube cell. Reirradiation of an optically bleached crystal by X-rays generates F D centers in it. The F D →M + A transformation in SrF 2 -Na crystals occurs at T = 135 K, in contrast to the F A →M + A transformations, which take place at T > 200 K [ru

  10. Laser damage studies on MgF2 thin films

    International Nuclear Information System (INIS)

    Protopapa, Maria Lucia; De Tomasi, Ferdinando; Perrone, Maria Rita; Piegari, Angela; Masetti, Enrico; Ristau, Detlev; Quesnel, Etienne; Duparre, Angela

    2001-01-01

    The results of laser damage studies performed at 248 nm (KrF excimer laser) on MgF 2 thin films deposited by different techniques (electron-beam evaporation, thermal boat evaporation, and ion-beam sputtering) on fused silica and CaF 2 substrates are presented. We find that the films deposited on CaF 2 substrates by the electron-beam evaporation technique present the highest damage threshold fluence (9 J/cm2). The photoacoustic (PA) beam deflection technique was employed, in addition to microscopical inspection, to determine laser damage fluences. We confirm, by scanning electron microscopy analysis of the damaged spots, the capability of the PA technique to provide information on the mechanisms leading to damage. The dependence of both laser damage fluence and damage morphology on the film deposition technique, as well as on the film substrate, is discussed

  11. Spin waves in antiferromagnetic FeF2

    DEFF Research Database (Denmark)

    Hutchings, M T; Rainford, B.D.; Guggenheim, H J

    1970-01-01

    Spin-wave dispersion in antiferromagnetic FeF2 has been investigated by inelastic neutron scattering using a chopper time-of-flight spectrometer. The single mode observed has a relatively flat dispersion curve rising from 53 cm-1 at the zone centre to 79 cm-1 at the zone boundary. A spin Hamilton......Spin-wave dispersion in antiferromagnetic FeF2 has been investigated by inelastic neutron scattering using a chopper time-of-flight spectrometer. The single mode observed has a relatively flat dispersion curve rising from 53 cm-1 at the zone centre to 79 cm-1 at the zone boundary. A spin...

  12. Association of immunity and tolerance of host H-2 determinants in irradiated F1 hybrid mice reconstituted with bone marrow cells from one parental strain

    International Nuclear Information System (INIS)

    Sprent, J.; von Boehmer, H.; Nabholz, M.

    1975-01-01

    Semiallogeneic radiation chimeras were prepared by injecting heavily irradiated F 1 hybrid mice with bone marrow cells from one parental strain; the bone marrow cells were treated with anti-theta serum and complement to remove T cells and injected in large numbers (2 x 10 7 cells). The mice survived in excellent health until sacrifice 6 mo later. Thoracic duct cannulation at this stage showed that the mice possessed normal numbers of recirculating lymphocytes. Close to 100 percent of thoracic duct lymphocytes and lymph node cells were shown to be of donor strain origin. The capacity of lymphocytes from the chimeras to respond to host-type determinants was tested in mixed leukocyte culture and in an assay for cell-mediated lympholysis (CML). Mixed leukocyte reactions (MLR) were measured both in vitro and in vivo; tumor cells and phytohemagglutinin-stimulated blast cells were used as target cells for measuring CML. While responding normally to third party determinants, cells from the chimeras gave a definite, though reduced MLR when exposed to host-type determinants. However, this proliferative response to host-type determinants, unlike that to third party determinants, was not associated with differentiation into cytotoxic lymphocytes

  13. Cloning, sequence analysis, and expression of the large subunit of the human lymphocyte activation antigen 4F2

    International Nuclear Information System (INIS)

    Lumadue, J.A.; Glick, A.B.; Ruddle, F.H.

    1987-01-01

    Among the earliest expressed antigens on the surface of activated human lymphocytes is the surface antigen 4F2. The authors have used DNA-mediated gene transfer and fluorescence-activated cell sorting to obtain cell lines that contain the gene encoding the large subunit of the human 4F2 antigen in a mouse L-cell background. Human DNAs cloned from these cell lines were subsequently used as hybridization probes to isolate a full-length cDNA clone expressing 4F2. Sequence analysis of the coding region has revealed an amino acid sequence of 529 residues. Hydrophobicity plotting has predicted a probable structure for the protein that includes an external carboxyl terminus, an internal leader sequence, a single hydrophobic transmembrane domain, and two possible membrane-associated domains. The 4F2 cDNA detects a single 1.8-kilobase mRNA in T-cell and B-cell lines. RNA gel blot analysis of RNA derived from quiescent and serum-stimulated Swiss 3T3 fibroblasts reveals a cell-cycle modulation of 4F2 gene expression: the mRNA is present in quiescent fibroblasts but increases 8-fold 24-36 hr after stimulation, at the time of maximal DNA synthesis

  14. Cloning, sequence analysis, and expression of the large subunit of the human lymphocyte activation antigen 4F2

    Energy Technology Data Exchange (ETDEWEB)

    Lumadue, J.A.; Glick, A.B.; Ruddle, F.H.

    1987-12-01

    Among the earliest expressed antigens on the surface of activated human lymphocytes is the surface antigen 4F2. The authors have used DNA-mediated gene transfer and fluorescence-activated cell sorting to obtain cell lines that contain the gene encoding the large subunit of the human 4F2 antigen in a mouse L-cell background. Human DNAs cloned from these cell lines were subsequently used as hybridization probes to isolate a full-length cDNA clone expressing 4F2. Sequence analysis of the coding region has revealed an amino acid sequence of 529 residues. Hydrophobicity plotting has predicted a probable structure for the protein that includes an external carboxyl terminus, an internal leader sequence, a single hydrophobic transmembrane domain, and two possible membrane-associated domains. The 4F2 cDNA detects a single 1.8-kilobase mRNA in T-cell and B-cell lines. RNA gel blot analysis of RNA derived from quiescent and serum-stimulated Swiss 3T3 fibroblasts reveals a cell-cycle modulation of 4F2 gene expression: the mRNA is present in quiescent fibroblasts but increases 8-fold 24-36 hr after stimulation, at the time of maximal DNA synthesis.

  15. Phenotypic and molecular characterization of a tomato (Solanum lycopersicum L.) F2 population segregation for improving shelf life.

    Science.gov (United States)

    Yogendra, K N; Ramanjini Gowda, P H

    2013-02-27

    Breeding for better quality fruits is a major focus for tomatoes, which are continuously subjected to post-harvest losses. Several methods have been used to improve the fruit shelf life of tomatoes, including the use of ripening gene mutants of Solanum lycopersicum. We developed extended shelf-life tomato hybrids with better quality fruits using ripening mutants. Nine tomato crosses were developed using 3 fruit ripening gene mutants of S. lycopersicum [alcobaca (alc), non-ripening, and ripening inhibitor] and 3 agronomically superior Indian cultivars ('Sankranti', 'Vaibhav', and 'Pusaruby') with short shelf life. The hybrid progenies developed from alc x 'Vaibhav' had the highest extended shelf life (up to 40 days) compared with that of other varieties and hybrids. Further, the F(2) progenies of alc x 'Vaibhav' were evaluated for fruit quality traits and yield parameters. A wide range of genetic variability was observed in shelf life (5-106 days) and fruit firmness (0.55-10.65 lbs/cm(2)). The potential polymorphic simple sequence repeat markers underlying shelf life traits were identified in an F(2) mapping population. The marker association with fruit quality traits and yield was confirmed with single-marker analysis and composite interval mapping. The genetic parameters analyzed in the parents and F(1) and F(2) populations indicated that the cross between the cultivar 'Vaibhav' and ripening gene mutant alc yielded fruit with long shelf life and good quality.

  16. Fitting the IRI F2-profile function to measured profiles

    International Nuclear Information System (INIS)

    Reinisch, B.W.; Huang Xueqin

    1997-01-01

    Comparison with profile data from ionosondes shows that the IRI bottomside F2-profiles can be improved by using better B0 and B1 parameters. The best parameters (in a least-squares sense) can be easily calculated in a numerical procedure from measured profiles presented as a sum of Chebyshev polynomials. 7 refs, 5 figs, 1 tab

  17. Fast exhaustive search for polynomial systems in F2

    NARCIS (Netherlands)

    Bouillaguet, C.; Chen, H.-C.; Cheng, C.M.; Chou, T.; Niederhagen, R.F.; Shamir, A.; Yang, B.Y.

    2010-01-01

    Abstract. We analyze how fast we can solve general systems of multivariate equations of various low degrees over F2; this is a well known hard problem which is important both in itself and as part of many types of algebraic cryptanalysis. Compared to the standard exhaustive-search technique, our

  18. Fast exhaustive search for polynomial systems in F2

    NARCIS (Netherlands)

    Bouillaguet, C.; Chen, H.-C.; Cheng, C.M.; Chou, T.; Niederhagen, R.F.; Shamir, A.; Yang, B.Y.; Mangard, S.; Standaert, F.X.

    2010-01-01

    Abstract: We analyze how fast we can solve general systems of multivariate equations of various low degrees over $F_2$; this is a well known hard problem which is important both in itself and as part of many types of algebraic cryptanalysis. Compared to the standard exhaustive search technique, our

  19. Genetic Dissection of a Key Reproductive Barrier Between Nascent Species of House Mice

    Science.gov (United States)

    White, Michael A.; Steffy, Brian; Wiltshire, Tim; Payseur, Bret A.

    2011-01-01

    Reproductive isolation between species is often caused by deleterious interactions among loci in hybrids. Finding the genes involved in these incompatibilities provides insight into the mechanisms of speciation. With recently diverged subspecies, house mice provide a powerful system for understanding the genetics of reproductive isolation early in the speciation process. Although previous studies have yielded important clues about the genetics of hybrid male sterility in house mice, they have been restricted to F1 sterility or incompatibilities involving the X chromosome. To provide a more complete characterization of this key reproductive barrier, we conducted an F2 intercross between wild-derived inbred strains from two subspecies of house mice, Mus musculus musculus and Mus musculus domesticus. We identified a suite of autosomal and X-linked QTL that underlie measures of hybrid male sterility, including testis weight, sperm density, and sperm morphology. In many cases, the autosomal loci were unique to a specific sterility trait and exhibited an effect only when homozygous, underscoring the importance of examining reproductive barriers beyond the F1 generation. We also found novel two-locus incompatibilities between the M. m. musculus X chromosome and M. m. domesticus autosomal alleles. Our results reveal a complex genetic architecture for hybrid male sterility and suggest a prominent role for reproductive barriers in advanced generations in maintaining subspecies integrity in house mice. PMID:21750261

  20. Genetic dissection of a key reproductive barrier between nascent species of house mice.

    Science.gov (United States)

    White, Michael A; Steffy, Brian; Wiltshire, Tim; Payseur, Bret A

    2011-09-01

    Reproductive isolation between species is often caused by deleterious interactions among loci in hybrids. Finding the genes involved in these incompatibilities provides insight into the mechanisms of speciation. With recently diverged subspecies, house mice provide a powerful system for understanding the genetics of reproductive isolation early in the speciation process. Although previous studies have yielded important clues about the genetics of hybrid male sterility in house mice, they have been restricted to F1 sterility or incompatibilities involving the X chromosome. To provide a more complete characterization of this key reproductive barrier, we conducted an F2 intercross between wild-derived inbred strains from two subspecies of house mice, Mus musculus musculus and Mus musculus domesticus. We identified a suite of autosomal and X-linked QTL that underlie measures of hybrid male sterility, including testis weight, sperm density, and sperm morphology. In many cases, the autosomal loci were unique to a specific sterility trait and exhibited an effect only when homozygous, underscoring the importance of examining reproductive barriers beyond the F1 generation. We also found novel two-locus incompatibilities between the M. m. musculus X chromosome and M. m. domesticus autosomal alleles. Our results reveal a complex genetic architecture for hybrid male sterility and suggest a prominent role for reproductive barriers in advanced generations in maintaining subspecies integrity in house mice.

  1. Fabrication and characterisation of nanostructures on CaF2

    International Nuclear Information System (INIS)

    Batzill, M.M.

    1999-04-01

    Novel nanostructure fabrication techniques are described in this dissertation. Furthermore, an unusual two dimensional phase segregation on CaF 2 surfaces after glancing incidence ion beam irradiation is reported. Atomic force microscope (AFM)-tip assisted self-organisation of clusters on anisotropic surfaces is illustrated. This new technique for the fabrication of periodic structures has been demonstrated using silver clusters grown on vicinal CaF 2 (111) surfaces. The scanning action of the tip aligns silver clusters along crystal step edges on the vicinal surface. Nanowire arrays of silver with a uniform periodicity of 20-50 nm and wire widths of 5-7 nm have been achieved over the entire area scanned by the AFM. Calcium remaining on CaF 2 surfaces after electron irradiation induced depletion of the surface of fluorine is found to re-organise itself into island structures. These islands show a shape transition, upon reaching a critical size of ∼ 20 nm in diameter, from a compact to an elongated island shape. Crystal step edge erosion of fluorine allows the formation of long ranging nanowires. These wires have a uniform width of ∼ 15 nm. The observed island shape transition and the width of the wires has been explained by the presence of strain in the islands. This is the first experimental observation confirming a theoretical prediction of the reduction of island width with increasing length for strained islands. A novel technique of ion beam assisted fabrication of periodic nanowire arrays over macroscopic areas is reported. Potential sputtering of CaF 2 surfaces leads to a calcium enriched surface that organised itself in stress domains due to the lattice misfit between calcium and CaF 2 . These stress domains can be oriented by directed ion beam irradiation under glancing angles in parallel stripes with a periodicity of 8-12 nm. A phase segregation on the CaF 2 (111) surface has been observed upon glancing incidence ion beam irradiation under certain

  2. Basal and induced granulopoiesis in outbred, F1 hybrid and inbred mice: can inbreeding depression influence the experimental practice?

    Czech Academy of Sciences Publication Activity Database

    Hofer, Michal; Pospíšil, Milan; Dušek, L.; Holá, Jiřina; Hoferová, Zuzana; Weiterová, Lenka

    2010-01-01

    Roč. 235, č. 8 (2010), s. 928-931 ISSN 1535-3702 R&D Projects: GA ČR(CZ) GA305/08/0158 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : hematopoiesis * outbred mice * inbreeding depression Subject RIV: BO - Biophysics Impact factor: 2.954, year: 2010

  3. F2 phenomenological test on fuel motion (Interim report)

    International Nuclear Information System (INIS)

    Palm, R.G.; Fink, C.L.; Stewart, R.R.; Gehl, S.M.; Rothman, A.B.

    1976-09-01

    TREAT F-series tests are being conducted to provide data on fuel motion at accident power levels from one to about ten times design for use in development of fuel motion models. Test F2 was conducted to evaluate motion of high power fuel in a hypothetical LMFBR unprotected TUC (transient undercooling) accident. Fuel and fuel-boundary conditions following coolant boiling and dryout under TUC conditions are achieved in each F-series test with a single fuel element surrounded by a nuclear heated wall in a dry test capsule. Test F2 was conducted with a low burnup but restructured fuel element to investigate the effect of fuel vapor pressure on fuel motion. Results are presented and discussed

  4. A detailed simulation of F2 measurability at HERA

    International Nuclear Information System (INIS)

    Bernardi, G.; Hildesheim, W.

    1992-01-01

    A study on the measurement of the F 2 proton structure function is presented, based on a realistic Monte Carlo of the H1 detector. The influence of systematic errors and detector acceptance on the values of x, y and Q 2 was studied in four independent reconstruction methods, based on: the electron only, the hadrons only, or 2 separate combinations of electronic and hadronic information. In particular, results from the combined measurement of y with the hadronic system, and Q 2 from the electron indicate that the evolution of F 2 will be measurable at low Q 2 (∼50 GeV 2 ) on two orders of magnitude in x. (authors) 10 refs., 10 figs

  5. Polycrystalline dosimetric discs of natural CaF2

    International Nuclear Information System (INIS)

    Okuno, E.; Ferreira, M.M.; Cruz, M.T.; Watanabe, S.

    1977-01-01

    A new method to prepare TL dosimeters in solid discs form, by the application of cold press in a mixture of KCL and fluorite in powder form, is investigated. By this method, it is possible to obtain thousands of dosimeters without difficulty much more uniform than that obtained from monocrystal ingots. The results show that the new dosimeters present the same properties as the fluorite in powder form, with the advantage that it is easier to handle in routine work. The ratio of 2 to 1 for KCL mass to CaF 2 mass presents good Tl sensitivity to ionizing radiation and sufficient mechanical resistivity. The minimum detectable exposure is approximately 10 mR. 83% from 442 CaF 2 solid discs gave TL response within 10% of mean value. Energy dependence is also presented [pt

  6. Luminescence of color centers in MgF2 crystals

    International Nuclear Information System (INIS)

    Vakhidov, Sh.A.; Nuritdinov, I.; Musaeva, M.A.

    1999-01-01

    The photoluminescence characteristics of the proper radiation color centers of the MgF 2 crystals are studied. The samples were irradiated by the 60 Co source γ-rays up to the dose 10 7 Gy. The bands with the maxima in the area of 420, 460, 550 and 620 nm were identified, which are excited correspondingly in the bands with the maxima of 370, 320, 410 and 480 nm

  7. Cleanup Verification Package for the 118-F-2 Burial Ground

    International Nuclear Information System (INIS)

    Capron, J.M.; Anselm, K.A.

    2008-01-01

    This cleanup verification package documents completion of remedial action, sampling activities, and compliance with cleanup criteria for the 118-F-2 Burial Ground. This burial ground, formerly called Solid Waste Burial Ground No. 1, was the original solid waste disposal site for the 100-F Area. Eight trenches contained miscellaneous solid waste from the 105-F Reactor and one trench contained solid waste from the biology facilities

  8. The rise in F$_{2}^{p}$ at HERA

    CERN Document Server

    Ball, Richard D.; Forte, S

    1994-01-01

    We show that the rise in F_2^p at small x and large Q^2 seen at HERA is indeed the non-Regge double asymptotic scaling behaviour expected from the perturbative emission of strongly ordered hard gluons. An alternative explanation, in which there is no strong ordering, and a new hard Reggeon is generated, is also tried but found wanting: its theoretical short-comings are betrayed by its failure to properly account for the HERA data.

  9. Male meiosis and gametogenesis in wild house mice (Mus musculus domesticus) from a chromosomal hybrid zone; a comparison between "simple" Robertsonian heterozygotes and homozygotes.

    Science.gov (United States)

    Wallace, B M; Searle, J B; Everett, C A

    1992-01-01

    Wild male house mice Mus musculus domesticus were collected from the hybrid zone between the John o'Groats race (2n = 32) and the standard race (2n = 40) in northern Scotland. Meiosis in both homozygotes (2n = 32, 36, and 40) and single Robertsonian heterozygotes (2n = 33, 35, and 37) was found to be orderly. At prophase/metaphase I in heterozygotes, a trivalent was formed from the metacentric and two homologous acrocentrics. At pachytene, this trivalent usually had a single side arm at the position of the centromeres, as a result of nonhomologous pairing of the acrocentrics. This side arm persisted into diplotene. Generally only a single chiasma was formed between each acrocentric and the metacentric. Anaphase I nondisjunction frequencies were estimated as 1.5% for the homozygotes and 2.7% for the heterozygotes. The extent of germ cell death between the pachytene and round spermatid stages was 18% greater in heterozygotes than in homozygotes. Our results concur with previous studies which indicate that single Robertsonian heterozygotes in wild house mice have near-normal fertility.

  10. NiF2/NaF:CaF2/Ca Solid-State High-Temperature Battery Cells

    Science.gov (United States)

    West, William; Whitacre, Jay; DelCastillo, Linda

    2009-01-01

    Experiments and theoretical study have demonstrated the promise of all-solid-state, high-temperature electrochemical battery cells based on NiF2 as the active cathode material, CaF2 doped with NaF as the electrolyte material, and Ca as the active anode material. These and other all-solid-state cells have been investigated in a continuing effort to develop batteries for instruments that must operate in environments much hotter than can be withstood by ordinary commercially available batteries. Batteries of this type are needed for exploration of Venus (where the mean surface temperature is about 450 C), and could be used on Earth for such applications as measuring physical and chemical conditions in geothermal wells and oil wells. All-solid-state high-temperature power cells are sought as alternatives to other high-temperature power cells based, variously, on molten anodes and cathodes or molten eutectic salt electrolytes. Among the all-solid-state predecessors of the present NiF2/NaF:CaF2/Ca cells are those described in "Solid-State High-Temperature Power Cells" (NPO-44396), NASA Tech Briefs, Vol. 32, No. 5 (May 2008), page 40. In those cells, the active cathode material is FeS2, the electrolyte material is a crystalline solid solution of equimolar amounts of Li3PO4 and LiSiO4, and the active anode material is Li contained within an alloy that remains solid in the intended high operational temperature range.

  11. The energy response of CaF2:Dy

    International Nuclear Information System (INIS)

    Ben-Shachar, B.; German, U.; Weiser, G.

    1982-11-01

    The energy response of CaF 2 :Dy was measured for 40-1250 keV photons and a very strong dependence was found below 200 keV. In order to fit the crystal to the requirements of the American Standards for Environmental Dosimetry, a number of filters which improve the energy dependence, were checked. It was found that the best filter is one which is made of 3 layers: tantalum, lead and aluminium, 0.018, 0.014 and 0.26 cm thick, respectively. (Author)

  12. An observation on F2 at low x

    International Nuclear Information System (INIS)

    Roeck, A. de; Wolf, E.A. de

    1996-08-01

    A simple parametrisation of H1 and ZEUS data at HERA is given for the ranges in x and Q 2 of 10 -4 -5.10 -2 and 5-250 GeV 2 , respectively. This empirical expression is based on a strikingly similar dependence of the average charged particle multiplicity on the centre of mass system energy √(s) in e + e - collisions on the one hand, and the x dependence of the proton structure function F 2 as measured at small x on the other hand. To the best of our knowledge, this similarity has not been noted before. (orig.)

  13. Atomic structure of CaF2/MnF2-Si(1 1 1) superlattices from X-ray diffraction

    International Nuclear Information System (INIS)

    Alcock, Simon G.; Nicklin, C.L.; Howes, P.B.; Norris, C.A.; Kyutt, R.N.; Sokolov, N.S.; Yakovlev, N.L.

    2007-01-01

    X-ray reflectivity and non-specular crystal truncation rod scans have been used to determine the three-dimensional atomic structure of the buried CaF 2 -Si(1 1 1) interface and ultrathin films of MnF 2 and CaF 2 within a superlattice. We show that ultrathin films of MnF 2 , below a critical thickness of approximately four monolayers, are crystalline, pseudomorphic, and adopt the fluorite structure of CaF 2 . High temperature deposition of the CaF 2 buffer layer produces a fully reacted, CaF 2 -Si(1 1 1) type-B interface. The mature, 'long' interface is shown to consist of a partially occupied layer of CaF bonded to the Si substrate, followed by a distorted CaF layer. Our atomistic, semi-kinematical scattering method extends the slab reflectivity method by providing in-plane structural information

  14. Metabolism of styrene to styrene oxide and vinylphenols in cytochrome P450 2F2- and P450 2E1-knockout mouse liver and lung microsomes.

    Science.gov (United States)

    Shen, Shuijie; Li, Lei; Ding, Xinxin; Zheng, Jiang

    2014-01-21

    Pulmonary toxicity of styrene is initiated by cytochromes P450-dependent metabolic activation. P450 2E1 and P450 2F2 are considered to be two main cytochrome P450 enzymes responsible for styrene metabolism in mice. The objective of the current study was to determine the correlation between the formation of styrene metabolites (i.e., styrene oxide and 4-vinylphenol) and pulmonary toxicity of styrene, using Cyp2e1- and Cyp2f2-null mouse models. A dramatic decrease in the formation of styrene glycol and 4-vinylphenol was found in Cyp2f2-null mouse lung microsomes relative to that in the wild-type mouse lung microsomes; however, no significant difference in the production of the styrene metabolites was observed between lung microsomes obtained from Cyp2e1-null and the wild-type mice. The knockout and wild-type mice were treated with styrene (6.0 mmol/kg, ip), and cell counts and LDH activity in bronchoalveolar lavage fluids were monitored to evaluate the pulmonary toxicity induced by styrene. Cyp2e1-null mice displayed a susceptibility to lung toxicity of styrene similar to that of the wild-type animals; however, Cyp2f2-null mice were resistant to styrene-induced pulmonary toxicity. In conclusion, both P450 2E1 and P450 2F2 are responsible for the metabolic activation of styrene. The latter enzyme plays an important role in styrene-induced pulmonary toxicity. Both styrene oxide and 4-vinylphenol are suggested to participate in the development of lung injury induced by styrene.

  15. Radiation induced genetic variability studies in M2 and F2M2 generation in chilli (Capsicum annum L.)

    International Nuclear Information System (INIS)

    Rangaiah, S.; Manjunath, A.; Naik, Puttarama; Gangappa, E.

    2002-01-01

    Chilli (Capsicum annum L.) is an important commercial crop in India. Mutation breeding is one of the effective tool to create new variability. Since, yield and its component characters show polygenic inheritance, information on amount of heritable portion of variability created through mutation for these characters is needed to use the induced variability for crop improvement. To harness more variability mutation has been superimposed on hybridization in several crops. The present study is undertaken to estimate the genetic variability induced through gamma irradiation for the polygenically inherited productive traits of chilli in M 2 and F 2 M 2 generation

  16. Radiation damage in BaF2 crystals

    International Nuclear Information System (INIS)

    Woody, C.L.; Kierstead, J.A.; Levy, P.W.; Stoll, S.

    1991-01-01

    The effects of radiation damage and recovery have been studied in BaF 2 crystals exposed to 60 Co radiation. The change in optical transmission and scintillation light output have been measured as a function of dose up to 4.7 x 10 6 rad. Although some crystals exhibit a small change in transmission, a greater change in scintillation light output is observed. Several 25 cm long crystals whichhave been irradiated show large changes in both transmission and light output. Recovery from radiation damage has been studied as a function of time and exposure to UV light. A long lived radiation induced phosphorescence has been observed in all irradiated samples which is distinct from the standard fast and slow scintillation emissions. The emission spectrum of the phosphorescence has been measured and shown a peakat ∼330 nm, near the region of the slow scintillation component. Results are given on the dependence of the decay time of the phosphorescence with dose

  17. Synthesis of CaF2: dy for thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Yamato, M.E.P.; Vasconcelos, D.A.A. de; Asfora, V.K.; Khoury, H.J.; Santos, R.A.; Barros, V.S.M.

    2015-01-01

    Calcium Fluoride doped with dysprosium is a known thermoluminescent material for applications that require highly sensitive dosimeters. Research in novel methods such as Combustion Synthesis (CS) has been ongoing for several years at the University of Pernambuco. The method uses the heat of the oxi-redox reaction a between nitrate and a fuel. This work presents results of CaF 2 :Dy produced by combustion synthesis under different fabrication conditions. Samples were prepared by mixing stoichiometric amounts of calcium nitrate, urea and ammonium nitrate in a beaker under vigorous stirring. The resulting gel was transferred to a pre-heated muffle furnace were the combustion reaction occurred after a few minutes. For comparison, a variation of the production method with the same amounts of nitrate, ammonium fluoride and dopant, but without using the fuel was prepared. For both methods the resulting powder was pelleted and irradiated with Co-60 gamma radiation. The reproducibility and sensitivity for gamma dose irradiation was tested and results showed that optimum TL sample reproducibility was without the urea as fuel. Samples were then prepared with 0.05, 0.10, 0.15 and 0.20 mol% Dy concentration. The highest TL sensitivity was found for samples with 0.15 mol% Dy and sintered at 400 deg C for 3.5 h in air. The TL emission spectra, obtained using a Hammamatsu optical spectrometer, was comparable with commercial CaF 2 :Dy. Thermoluminescence was measured in a Harshaw-Bicron 3500 TL Reader. The glow curve showed stable dosimetric peaks at around 200, 235 and 300 deg C were a linear dose response curve was obtained for the range 100 mGy to 1000 mGy. (author)

  18. Scintillation and radiation damage of doped BaF2 crystals

    International Nuclear Information System (INIS)

    Gong Zufang; Xu Zizong; Chang Jin

    1992-01-01

    The emission spectra and the radiation damage of BaF 2 crystals doped Ce and Dy have been studied. The results indicate that the doped BaF 2 crystals have the intrinsic spectra of impurity besides the intrinsic spectra of BaF 2 crystals. The crystals colored and the transmissions decrease with the concentration of impurity in BaF 2 crystals after radiation by γ-ray of 60 Co. The doped Ce BaF 2 irradiated by ultraviolet has faster recover of transmissions but for doped Dy the effect is not obvious. The radiation resistance is not good as pure BaF 2 crystals

  19. Defect-induced wetting on BaF 2(111) and CaF 2(111) at ambient conditions

    Science.gov (United States)

    Cardellach, M.; Verdaguer, A.; Fraxedas, J.

    2011-12-01

    The interaction of water with freshly cleaved (111) surfaces of isostructural BaF2 and CaF2 single crystals at ambient conditions (room temperature and under controlled humidity) has been studied using scanning force microscopy in different operation modes and optical microscopy. Such surfaces exhibit contrasting behaviors for both materials: while on BaF2(111) two-dimensional water layers are formed after accumulation at step edges, CaF2(111) does not promote the formation of such layers. We attribute such opposed behavior to lattice match (mismatch) between hexagonal water ice and the hexagonal (111) surfaces of BaF2(CaF2). Optical microscope images reveal that this behavior also determines the way the surfaces become wetted at a macroscopic level.

  20. CYP2F2-generated metabolites, not styrene oxide, are a key event mediating the mode of action of styrene-induced mouse lung tumors.

    Science.gov (United States)

    Cruzan, G; Bus, J; Hotchkiss, J; Harkema, J; Banton, M; Sarang, S

    2012-02-01

    Styrene induces lung tumors in mice but not in rats. Although metabolism of styrene to 7,8-styrene oxide (SO) by CYP2E1 has been suggested as a mediator of styrene toxicity, lung toxicity is not attenuated in CYP2E1 knockout mice. However, styrene and/or SO metabolism by mouse lung Clara cell-localized CYP2F2 to ring-oxidized cytotoxic metabolite(s) has been postulated as a key metabolic gateway responsible for both lung toxicity and possible tumorigenicity. To test this hypothesis, the lung toxicity of styrene and SO was evaluated in C57BL/6 (WT) and CYP2F2⁻/⁻ knockout mice treated with styrene (400 mg/kg/day, gavage, or 200 or 400 mg/kg/day, ip) or S- or R-SO (200 mg/kg/day, ip) for 5 days. Styrene treated WT mice displayed significant necrosis and exfoliation of Clara cells, and cumulative BrdU-labeling index of S-phase cells was markedly increased in terminal bronchioles of WT mice exposed to styrene or S- or RSO. In contrast, Clara and terminal bronchiole cell toxicity was not observed in CYP2F2⁻/⁻ mice exposed to either styrene or SO. This study clearly demonstrates that the mouse lung toxicity of both styrene and SO is critically dependent on metabolism by CYP2F2. Importantly, the human isoform of CYP2F, CYP2F1, is expressed at much lower levels and likely does not catalyze significant styrene metabolism, supporting the hypothesis that styrene-induced mouse lung tumors may not quantitatively, or possibly qualitatively, predict lung tumor potential in humans. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Novel and easy access to highly luminescent Eu and Tb doped ultra-small CaF2, SrF2 and BaF2 nanoparticles - structure and luminescence.

    Science.gov (United States)

    Ritter, Benjamin; Haida, Philipp; Fink, Friedrich; Krahl, Thoralf; Gawlitza, Kornelia; Rurack, Knut; Scholz, Gudrun; Kemnitz, Erhard

    2017-02-28

    A universal fast and easy access at room temperature to transparent sols of nanoscopic Eu 3+ and Tb 3+ doped CaF 2 , SrF 2 and BaF 2 particles via the fluorolytic sol-gel synthesis route is presented. Monodisperse quasi-spherical nanoparticles with sizes of 3-20 nm are obtained with up to 40% rare earth doping showing red or green luminescence. In the beginning luminescence quenching effects are only observed for the highest content, which demonstrates the unique and outstanding properties of these materials. From CaF 2 :Eu10 via SrF 2 :Eu10 to BaF 2 :Eu10 a steady increase of the luminescence intensity and lifetime occurs by a factor of ≈2; the photoluminescence quantum yield increases by 29 to 35% due to the lower phonon energy of the matrix. The fast formation process of the particles within fractions of seconds is clearly visualized by exploiting appropriate luminescence processes during the synthesis. Multiply doped particles are also available by this method. Fine tuning of the luminescence properties is achieved by variation of the Ca-to-Sr ratio. Co-doping with Ce 3+ and Tb 3+ results in a huge increase (>50 times) of the green luminescence intensity due to energy transfer Ce 3+ → Tb 3+ . In this case, the luminescence intensity is higher for CaF 2 than for SrF 2 , due to a lower spatial distance of the rare earth ions.

  2. Genetic injury in hybrid male mice exposed to low doses of 60CO γ-rays or fission neutrons. 1

    International Nuclear Information System (INIS)

    Grahn, D.; Carnes, B.A.; Farrington, B.H.; Lee, C.H.

    1984-01-01

    Young adult male B6CF 1 mice were exposed to single whole body doses of fission neutrons or 60 Co γ rays. Postspermatogonial dominant lethal injury, incidence of reciprocal chromosome translocations induced in spermatogonia, incidence of abnormal epididymal sperm 4-6 weeks after exposure, and testis weight loss 3-6 weeks after exposure were all measured. Significant effects were seen at 1 and 2.5 rad of neutrons consistent with extrapolation from higher doses, with the exception of dominant lethal mutations, which occurred in significant excess of expectation. Dose-response functions were linear or linear-quadratic, depending upon end point, radiation quality, and dose range. For translocation frequencies, the D 2 term was negative for neutron and positive for γ-ray irradiations. RBE values varied with dose and end point. For testis weight loss and abnormal sperm over the full dose range, the RBEs were between 5 and 6. They were between 7 and 9 at lower doses (< 10 rad) for translocations. RBEs for postimplantation and total dominant lethal rates were 5-6 above 10 rad and 10-14 below 10 rad. The RBEs for preimplant losses were between 15 and 25 above 10 rad and possibly higher below 10 rad, although the data are statistically 'noisy'. (Auth.)

  3. High Incidence of Thymic Epithelial Tumors in E2F2 Transgenic Mice

    NARCIS (Netherlands)

    Scheijen, B.; Bronk, M.; Meer, T. van der; Jong, D. de; Bernards, R.A.

    2004-01-01

    In virtually all human tumors, genetic and epigenetic alterations have been found which affect the INK4/-CYCLIN D/RB pathway, which regulates cell cycle entry and exit in normal cells. E2F transcription factors are important downstream components of this pathway, which act by controlling the

  4. Genomic locus modulating corneal thickness in the mouse identifies POU6F2 as a potential risk of developing glaucoma.

    Directory of Open Access Journals (Sweden)

    Rebecca King

    2018-01-01

    Full Text Available Central corneal thickness (CCT is one of the most heritable ocular traits and it is also a phenotypic risk factor for primary open angle glaucoma (POAG. The present study uses the BXD Recombinant Inbred (RI strains to identify novel quantitative trait loci (QTLs modulating CCT in the mouse with the potential of identifying a molecular link between CCT and risk of developing POAG. The BXD RI strain set was used to define mammalian genomic loci modulating CCT, with a total of 818 corneas measured from 61 BXD RI strains (between 60-100 days of age. The mice were anesthetized and the eyes were positioned in front of the lens of the Phoenix Micron IV Image-Guided OCT system or the Bioptigen OCT system. CCT data for each strain was averaged and used to QTLs modulating this phenotype using the bioinformatics tools on GeneNetwork (www.genenetwork.org. The candidate genes and genomic loci identified in the mouse were then directly compared with the summary data from a human POAG genome wide association study (NEIGHBORHOOD to determine if any genomic elements modulating mouse CCT are also risk factors for POAG.This analysis revealed one significant QTL on Chr 13 and a suggestive QTL on Chr 7. The significant locus on Chr 13 (13 to 19 Mb was examined further to define candidate genes modulating this eye phenotype. For the Chr 13 QTL in the mouse, only one gene in the region (Pou6f2 contained nonsynonymous SNPs. Of these five nonsynonymous SNPs in Pou6f2, two resulted in changes in the amino acid proline which could result in altered secondary structure affecting protein function. The 7 Mb region under the mouse Chr 13 peak distributes over 2 chromosomes in the human: Chr 1 and Chr 7. These genomic loci were examined in the NEIGHBORHOOD database to determine if they are potential risk factors for human glaucoma identified using meta-data from human GWAS. The top 50 hits all resided within one gene (POU6F2, with the highest significance level of p = 10-6 for

  5. Ab initio study of dissociative attachment of low-energy electrons to F2

    International Nuclear Information System (INIS)

    Hazi, A.U.; Orel, A.E.; Rescigno, T.N.

    1981-01-01

    Adiabatic-nuclei resonance theory has been applied to the study of dissociative attachment of low-energy electrons to F 2 . Stieltjes moment theory was used to derive fixed-nuclei electronic resonance parameters from large scale configuration-interaction calculations on F 2 and F 2 - . Dissociative attachment cross sections are reported for the four lowest vibrational levels of F 2 and compared to available experimental data

  6. 17 CFR 270.17f-2 - Custody of investments by registered management investment company.

    Science.gov (United States)

    2010-04-01

    ... registered management investment company. 270.17f-2 Section 270.17f-2 Commodity and Securities Exchanges....17f-2 Custody of investments by registered management investment company. (a) The securities and similar investments of a registered management investment company may be maintained in the custody of such...

  7. Anomalous variations of NmF2 over the Argentine Islands: a statistical study

    Directory of Open Access Journals (Sweden)

    A. V. Pavlov

    2009-04-01

    Full Text Available We present a statistical study of variations in the F2-layer peak electron density, NmF2, and altitude, hmF2, over the Argentine Islands ionosonde. The critical frequencies, foF2, and, foE, of the F2 and E-layers, and the propagation factor, M(3000F2, measured by the ionosonde during the 1957–1959 and 1962–1995 time periods were used in the statistical analysis to determine the values of NmF2 and hmF2. The probabilities to observe maximum and minimum values of NmF2 and hmF2 in a diurnal variation of the electron density are calculated. Our study shows that the main part of the maximum diurnal values of NmF2 is observed in a time sector close to midnight in November, December, January, and February exhibiting the anomalous diurnal variations of NmF2. Another anomalous feature of the diurnal variations of NmF2 exhibited during November, December, and January when the minimum diurnal value of NmF2 is mainly located close to the noon sector. These anomalous diurnal variations of NmF2 are found to be during both geomagnetically quiet and disturbed conditions. Anomalous features are not found in the diurnal variations of hmF2. The statistical study of the NmF2 winter anomaly phenomena over the Argentine Islands ionosonde was carried out. The variations in a maximum daytime value, R, of a ratio of a geomagnetically quiet daytime winter NmF2 to a geomagnetically quiet daytime summer NmF2 taken at a given UT and for approximately the same level of solar activity were studied. The conditional probability of the occurrence of R in an interval of R, the most frequent value of R, the mean expected value of R, and the conditional probability to observe the F2-region winter anomaly during a daytime period were calculated for low, moderate, and high solar activity. The calculations show that the mean expected value of R and the occurrence frequency of the F2-region winter anomaly increase with increasing solar activity.

  8. Disjunction or non-disjunction in F2 generation according to the cross between a wheat mutant and its original lines

    International Nuclear Information System (INIS)

    Touvin, H.

    1973-01-01

    An early homogeneous mutant line (B) was obtained in M 2 generation following the gamma-rays (15kR) treatment of the dry seeds of a fixed homogeneous line of soft wheat (A). The study of this mutant leads to the following observations: the earliness is stable in the mutant stock during successive generations and in different climatic conditions; the products of reciprocal crosses between the mutant B and the original line A, compared in micro-tests under greenhouse conditions gave following different results according to the cross; in the F 1 , the reciprocal hybrids (AxB, BxA) are earlier than the mutant. The F 1 offsprings (BxA) which received the earliness characteristic from the female parent, develop more rapidly than the reciprocal F 1 hybrid (AxB). Thus, this shows that there exist a maternal effect from the mutant side. In the F 2 , the descendants of the hybrid (AxB) segregated phenotypically in two classes, early and late, whereas the other hybrid (BxA) produces only early plants. The F 3 offsprings confirm the observations made in the F 2 generation. Although the F 3 generation of the hybrid (AxB) is composed of the early homogenous, the heterogeneous and the late homogeneous lines, but no segregation occurs in the cross (BxA). The segregation ratio in F 2 and in most of the backcrosses progenies indicates that the transmission of the earliness character is monogenic. From these results the existence of a major gene for earliness can be supposed, the expression of which appears to be under the control of the cytoplasm. The conclusion emphasizes the importance of the reciprocal crosses in the use of the mutants [fr

  9. Computation of the chiral condensate using N{sub f}=2 and N{sub f}=2+1+1 dynamical flavors of twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Cichy, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Poznan Univ. (Poland). Faculty of Physics; Garcia-Ramos, E. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Humboldt-Universitaet, Berlin (Germany); Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Shindler, A. [Forschungszentrum Juelich (Germany). IAS; Forschungszentrum Juelich (Germany). IKP; Forschungszentrum Juelich (Germany). JCHP; Collaboration: European Twisted Mass Collaboration

    2013-12-15

    We apply the spectral projector method, recently introduced by Giusti and Luescher, to compute the chiral condensate using N{sub f}=2 and N{sub f}=2+1+1 dynamical flavors of maximally twisted mass fermions. We present our results for several quark masses at three different lattice spacings which allows us to perform the chiral and continuum extrapolations. In addition we report our analysis on the O(a) improvement of the chiral condensate for twisted mass fermions. We also study the effect of the dynamical strange and charm quarks by comparing our results for N{sub f}=2 and N{sub f}=2+1+1 dynamical flavors.

  10. Complex refractive index measurements for BaF 2 and CaF 2 via single-angle infrared reflectance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kelly-Gorham, Molly Rose K.; DeVetter, Brent M.; Brauer, Carolyn S.; Cannon, Bret D.; Burton, Sarah D.; Bliss, Mary; Johnson, Timothy J.; Myers, Tanya L.

    2017-10-01

    We have re-investigated the optical constants n and k for the homologous series of inorganic salts barium fluoride (BaF2) and calcium fluoride (CaF2) using a single-angle near-normal incidence reflectance device in combination with a calibrated Fourier transform infrared (FTIR) spectrometer. Our results are in good qualitative agreement with most previous works. However, certain features of the previously published data near the reststrahlen band exhibit distinct differences in spectral characteristics. Notably, our measurements of BaF2 do not include a spectral feature in the ~250 cm-1 reststrahlen band that was previously published. Additionally, CaF2 exhibits a distinct wavelength shift relative to the model derived from previously published data. We confirmed our results with recently published works that use significantly more modern instrumentation and data reduction techniques

  11. Dipole model analysis of F2cc¯${m{F}}_2^{{m{car c}}} $ derived from the new D* data in DIS at HERA

    Directory of Open Access Journals (Sweden)

    Luszczak Agnieszka

    2012-12-01

    Full Text Available I analyse the new D* deep inelastic scattering data from HERA with the help of dipole models. I calculate F2cc¯${m{F}}_2^{{m{car c}}} $ from the GBW [1] and BGK [2] saturation models. I compare results with the last values determined by H1 at low Q2. I find good agreement with the data.

  12. Variability of critical frequency and M(3000)F2 at Tucuman and San Juan

    International Nuclear Information System (INIS)

    Ezquer, R.G.; Mosert, M.; Corbella, R.J.

    2002-01-01

    The variability of the M(3000)F2 factor and the critical frequency of the E and F2 ionospheric regions over two argentine stations for middle solar activity conditions is studied. To this end different parameters to specify variability are used, namely: standard deviation, difference between median to lower quartile and to upper quartile. The results show that low variability is observed for foE and M(3000)F2 factor at both stations for equinoxes and solstices. The coefficients of variability are lower than 10% for foE and M(3000)F2 factor. The highest variability was observed for foF2. In general, the foF2 coefficient of variability ranges between 0 and 30%, at both stations. (author)

  13. Resistance Switching Memory Characteristics of Si/CaF2/CdF2 Quantum-Well Structures Grown on Metal (CoSi2) Layer

    Science.gov (United States)

    Denda, Junya; Uryu, Kazuya; Watanabe, Masahiro

    2013-04-01

    A novel scheme of resistance switching random access memory (ReRAM) devices fabricated using Si/CaF2/CdF2/CaF2/Si quantum-well structures grown on metal CoSi2 layer formed on a Si substrate has been proposed, and embryonic write/erase memory operation has been demonstrated at room temperature. It has been found that the oxide-mediated epitaxy (OME) technique for forming the CoSi2 layer on Si dramatically improves the stability and reproducibility of the current-voltage (I-V) curve. This technology involves 10-nm-thick Co layer deposition on a protective oxide prepared by boiling in a peroxide-based solution followed by annealing at 550 °C for 30 min for silicidation in ultrahigh vacuum. A switching voltage of lower than 1 V, a peak current density of 32 kA/cm2, and an ON/OFF ratio of 10 have been observed for the sample with the thickness sequence of 0.9/0.9/2.5/0.9/5.0 nm for the respective layers in the Si/CaF2/CdF2/CaF2/Si structure. Results of surface morphology analysis suggest that the grain size of crystal islands with flat surfaces strongly affects the quality of device characteristics.

  14. The characteristics of CaF2:Tm crystals (TLD-300) irradiated by electromagnetic radiation

    International Nuclear Information System (INIS)

    Ben-Shachar, B.; Yona, S.; Laichter, Y.; German, U.; Weiser, G.

    1985-09-01

    The main characteristics of the CaF 2 :Tm crystals (TLD-300), as a dosimeter, were measured: the glow curve, sensitivity, linearity, fading and energy dependence for photons, and compared to those of LiF (TLD-100) and CaF 2 :Dy (TLD-200). It was found that CaF 2 :Tm can be used for environmental dosimetry by reading the crystals after four days. (Author)

  15. Expression and Functional Pathway Analysis of Nuclear Receptor NR2F2 in Ovarian Cancer

    Science.gov (United States)

    Hawkins, Shannon M.; Loomans, Holli A.; Wan, Ying-Wooi; Ghosh-Choudhury, Triparna; Coffey, Donna; Xiao, Weimin; Liu, Zhandong; Sangi-Haghpeykar, Haleh

    2013-01-01

    Context: Recent evidence implicates the orphan nuclear receptor, nuclear receptor subfamily 2, group F, member 2 (NR2F2; chicken ovalbumin upstream promoter-transcription factor II) as both a master regulator of angiogenesis and an oncogene in prostate and other human cancers. Objective: The objective of the study was to determine whether NR2F2 plays a role in ovarian cancer and dissect its potential mechanisms of action. Design, Setting, and Patients: We examined NR2F2 expression in healthy ovary and ovarian cancers using quantitative PCR and immunohistochemistry. NR2F2 expression was targeted in established ovarian cancer cell lines to assess the impact of dysregulated NR2F2 expression in the epithelial compartment of ovarian cancers. Results: Our results indicate that NR2F2 is robustly expressed in the stroma of healthy ovary with little or no expression in epithelia lining the ovarian surface, clefts, or crypts. This pattern of NR2F2 expression was markedly disrupted in ovarian cancers, in which decreased levels of stromal expression and ectopic epithelial expression were frequently observed. Ovarian cancers with the most disrupted patterns of NR2F2 were associated with significantly shorter disease-free interval by Kaplan-Meier analysis. Targeting NR2F2 expression in established ovarian cancer cell lines enhanced apoptosis and increased proliferation. In addition, we found that NR2F2 regulates the expression of NEK2, RAI14, and multiple other genes involved in the cell cycle, suggesting potential pathways by which dysregulated expression of NR2F2 impacts ovarian cancer. Conclusions: These results uncover novel roles for NR2F2 in ovarian cancer and point to a unique scenario in which a single nuclear receptor plays potentially distinct roles in the stromal and epithelial compartments of the same tissue. PMID:23690307

  16. Investigation of the relationship between ionospheric foF2 and earthquakes

    Science.gov (United States)

    Karaboga, Tuba; Canyilmaz, Murat; Ozcan, Osman

    2018-04-01

    Variations of the ionospheric F2 region critical frequency (foF2) have been investigated statistically before earthquakes during 1980-2008 periods in Japan area. Ionosonde data was taken from Kokubunji station which is in the earthquake preparation zone for all earthquakes. Standard Deviations and Inter-Quartile Range methods are applied to the foF2 data. It is observed that there are anomalous variations in foF2 before earthquakes. These variations can be regarded as ionospheric precursors and may be used for earthquake prediction.

  17. NmF2 and hmF2 measurements at 95° E and 127° E around the EIA northern crest during 2010-2014

    Science.gov (United States)

    Kalita, Bitap Raj; Bhuyan, Pradip Kumar; Yoshikawa, Akimasa

    2015-11-01

    The characteristics of the F2 layer parameters NmF2 and hmF2 over Dibrugarh (27.5° N, 95° E, 17° N geomagnetic, 43° dip) measured by a Canadian Advanced Digital Ionosonde (CADI) for the period of August 2010 to July 2014 are reported for the first time from this low mid-latitude station lying within the daytime peak of the longitudinal wave number 4 structure of equatorial anomaly (EIA) around the northern edge of anomaly crest. Equinoctial asymmetry is clearly observed at all solar activity levels whereas the midday winter anomaly is observed only during high solar activity years and disappears during the temporary dip in solar activity in 2013 but forenoon winter anomaly can be observed even at moderate solar activity. The NmF2/hmF2 variations over Dibrugarh are compared with that of Okinawa (26.5° N, 127° E, 17° N geomagnetic), and the eastward propagation speed of the wave number 4 longitudinal structure from 95° E to 127° E is estimated. The speed is found to be close to the theoretical speed of the wave number 4 (WN4) structure. The correlation of daily NmF2 over Dibrugarh and Okinawa with solar activity exhibits diurnal and seasonal variations. The highest correlation in daytime is observed during the forenoon hours in equinox. The correlation of daily NmF2 (linear or non-linear) with solar activity exhibits diurnal variation. A tendency for amplification with solar activity is observed in the forenoon and late evening period of March equinox and the postsunset period of December solstice. NmF2 saturation effect is observed only in the midday period of equinox. Non-linear variation of neutral composition at higher altitudes and variation of recombination rates with solar activity via temperature dependence may be related to the non-linear trend. The noon time maximum NmF2 over Dibrugarh exhibits better correlation with equatorial electrojet (EEJ) than with solar activity and, therefore, new low-latitude NmF2 index is proposed taking both solar

  18. Molecular cloning of complementary DNAs encoding the heavy chain of the human 4F2 cell-surface antigen: a type II membrane glycoprotein involved in normal and neoplastic cell growth

    International Nuclear Information System (INIS)

    Quackenbush, E.; Clabby, M.; Gottesdiener, K.M.; Barbosa, J.; Jones, N.H.; Strominger, J.L.; Speck, S.; Leiden, J.M.

    1987-01-01

    Complementary DNA (cDNA) clones encoding the heavy chain of the heterodimeric human membrane glycoprotein 4F2 have been isolated by immunoscreening of a λgt11 expression library. The identity of these clones has been confirmed by hybridization to RNA and DNA prepared from mouse L-cell transfectants, which were produced by whole cell gene transfer and selected for cell-surface expression of the human 4F2 heavy chain. DNA sequence analysis suggest that the 4F2 heavy-chain cDNAs encode an approximately 526-amino acid type II membrane glycoprotein, which is composed of a large C-terminal extracellular domain, a single potential transmembrane region, and a 50-81 amino acid N-terminal intracytoplasmic domain. Southern blotting experiments have shown that the 4F2 heavy-chain cDNAs are derived from a single-copy gene that has been highly conserved during mammalian evolution

  19. Comparison of foE and M(3000)F2 variability at Ibadan, Singapore and Slough

    Science.gov (United States)

    Somoye, E. O.; Onori, E. O.; Akala, A. O.

    2013-01-01

    The variability, VR, of critical frequency of E-layer, foE, and ionospheric propagation factor, M(3000)F2 at Ibadan (7.4°N, 3.9°E, 6°S dip) is investigated for local time, seasonal and solar cycle variations. Latitudinal influence of these characteristics is sought by comparison with foE VR and M(3000)F2 VR of Slough ( 51.5°N, 359.4°E, 66.5°N dip) in the European sector, and Singapore (1.3°N,103.8°E, 17.6°S dip) in the Asian sector. While the pattern of foE VR is similar to those of other F2 characteristics with characteristic peaks around dawn and dusk, M(3000)F2 VR shows no clear diurnal trend.A lower bound of foE VR is usually 3% while the maximum VR ranges between 8% and13% at post-sunrise and pre-sunset hours at all the epochs, M(3000)F2 VR is however lower during MSA (about 9%) than during LSA and HSA when it is 4% to about 12-14%. Generally, daytime M(3000)F2 VR is greater than that of foE VR by between 5% and 10%. Furthermore, no latitudinal difference is observed in both characteristics during both HSA and MSA. While nighttime M(3000)F2 VR is about half that of nighttime foF2 VR (the critical frequency of F2-layer ) VR, daytime VR of both characteristics are about equal during the three epochs at Ibadan. For Slough, nighttime M(3000)F2 VR and nighttime foF2 VR as well as the daytime VR of both characteristics are about equal. This difference is most likely due to latitudinal effect.

  20. Annual and semiannual variations in the ionospheric F2-layer. I. Modelling

    Directory of Open Access Journals (Sweden)

    L. Zou

    2000-08-01

    Full Text Available Annual, seasonal and semiannual variations of F2-layer electron density (NmF2 and height (hmF2 have been compared with the coupled thermosphere-ionosphere-plasmasphere computational model (CTIP, for geomagnetically quiet conditions. Compared with results from ionosonde data from midlatitudes, CTIP reproduces quite well many observed features of NmF2, such as the dominant winter maxima at high midlatitudes in longitude sectors near the magnetic poles, the equinox maxima in sectors remote from the magnetic poles and at lower latitudes generally, and the form of the month-to-month variations at latitudes between about 60°N and 50°S. CTIP also reproduces the seasonal behaviour of NmF2 at midnight and the summer-winter changes of hmF2. Some features of the F2-layer, not reproduced by the present version of CTIP, are attributed to processes not included in the modelling. Examples are the increased prevalence of the winter maxima of noon NmF2 at higher solar activity, which may be a consequence of the increase of F2-layer loss rate in summer by vibrationally excited molecular nitrogen, and the semiannual variation in hmF2, which may be due to tidal effects. An unexpected feature of the computed distributions of NmF2 is an east-west hemisphere difference, which seems to be linked to the geomagnetic field configuration. Physical discussion is reserved to the companion paper by Rishbeth et al.Key words: Atmospheric composition and structure (thermosphere-composition and chemistry - Ionosphere (mid-latitude ionosphere; modelling and forecasting

  1. Annual and semiannual variations in the ionospheric F2-layer. I. Modelling

    Directory of Open Access Journals (Sweden)

    L. Zou

    Full Text Available Annual, seasonal and semiannual variations of F2-layer electron density (NmF2 and height (hmF2 have been compared with the coupled thermosphere-ionosphere-plasmasphere computational model (CTIP, for geomagnetically quiet conditions. Compared with results from ionosonde data from midlatitudes, CTIP reproduces quite well many observed features of NmF2, such as the dominant winter maxima at high midlatitudes in longitude sectors near the magnetic poles, the equinox maxima in sectors remote from the magnetic poles and at lower latitudes generally, and the form of the month-to-month variations at latitudes between about 60°N and 50°S. CTIP also reproduces the seasonal behaviour of NmF2 at midnight and the summer-winter changes of hmF2. Some features of the F2-layer, not reproduced by the present version of CTIP, are attributed to processes not included in the modelling. Examples are the increased prevalence of the winter maxima of noon NmF2 at higher solar activity, which may be a consequence of the increase of F2-layer loss rate in summer by vibrationally excited molecular nitrogen, and the semiannual variation in hmF2, which may be due to tidal effects. An unexpected feature of the computed distributions of NmF2 is an east-west hemisphere difference, which seems to be linked to the geomagnetic field configuration. Physical discussion is reserved to the companion paper by Rishbeth et al.

    Key words: Atmospheric composition and structure (thermosphere-composition and chemistry - Ionosphere (mid-latitude ionosphere; modelling and forecasting

  2. Ultraviolet radiation dosimetry using CaF2 TL phosphors- state of the art

    International Nuclear Information System (INIS)

    Nagpal, J.S.

    2001-01-01

    Photoluminescence (PL), optical absorption (OA) and thermoluminescence (TL) of undoped and Dy, Tb- and Eu activated CaF 2 TL phosphors has been re-investigated after heat treatment (600-1100 degC) in air. The study confirmed the earlier observed increase in intrinsic UV response of CaF 2 : Dy 3+ after 900 degC heat treatment. Enhancement in UV response was also observed in undoped CaF 2 thus indicating the base matrix related phenomenon. However, the enhancement observed in UV sensitivity and the optimum treatment temperature for high UV sensitivity is different for different activators. It is activator specific and needs further probing. UV response of undoped CaF 2 monotonically increases as the treatment temperature (in air) is increased from 600 degC to 1100 degC. Similar increase is observed in case of CaF 2 : Tb 3+ also. However, CaF 2 : Dy 3+ and CaF 2 :Eu 2+ follow a different pattern. Heat treatment in air increases UV response of CaF 2 : Dy 3+ up to 900 degC, and a decrease is observed at higher temperatures. UV response of CaF 2 : Eu 2+ is maximum for 600 degC treatment in air and decreases thereafter. TL response of CaF 2 : Tb and CaF 2 : Eu 2+ phosphors to UV is high, can be employed over the range 10 -2 - 2 mJ.cm -2 and is rate independent for 250±10 nm UV. (author)

  3. Representation of the Coulomb Matrix Elements by Means of Appell Hypergeometric Function F 2

    Science.gov (United States)

    Bentalha, Zine el abidine

    2018-06-01

    Exact analytical representation for the Coulomb matrix elements by means of Appell's double series F 2 is derived. The finite sum obtained for the Appell function F 2 allows us to evaluate explicitly the matrix elements of the two-body Coulomb interaction in the lowest Landau level. An application requiring the matrix elements of Coulomb potential in quantum Hall effect regime is presented.

  4. Supplementary data: Table 1. QTL for tassel related traits of F2:3 ...

    Indian Academy of Sciences (India)

    User

    Supplementary data: Table 1. QTL for tassel related traits of F2:3 population across and RIL population through single-environment analysis (SEA). Trait. Population. Environment. QTL. Binlocusa. Flanking marker. Peak position. (cM). Range. (cM)b. Ac. Dd. Gene actione. R2(%)f. Subtotal R2. (%)g. F(0.05)h type. TTL. F2:3.

  5. Role of MgF2 on properties of glass–ceramics

    Indian Academy of Sciences (India)

    Al2O3–K2O–B2O3–F with and with- out addition of MgF2 has been investigated. Crystallization of glass sample was done by controlled thermal heat treatment at nucleation and crystallization temperatures. The results showed that MgF2 in high ...

  6. Elastic properties of Na 2 O–ZnO–ZnF 2

    Indian Academy of Sciences (India)

    Elastic properties of Na2O–ZnO–ZnF2–B2O3 oxyfluoride glasses with different ZnF2 concentrations have been investigated using ultrasonic velocity measurements at room temperature, at a frequency of 10 MHz. Glasses prepared by melt quenching method were suitably polished for the ultrasonic velocity measurements ...

  7. Structural Phase Transition and Compressibility of CaF2 Nanocrystals under High Pressure

    Directory of Open Access Journals (Sweden)

    Jingshu Wang

    2018-05-01

    Full Text Available The structural phase transition and compressibility of CaF2 nanocrystals with size of 23 nm under high pressure were investigated by synchrotron X-ray diffraction measurement. A pressure-induced fluorite to α-PbCl2-type phase transition starts at 9.5 GPa and completes at 20.2 GPa. The phase-transition pressure is lower than that of 8 nm CaF2 nanocrystals and closer to bulk CaF2. Upon decompression, the fluorite and α-PbCl2-type structure co-exist at the ambient pressure. The bulk modulus B0 of the 23 nm CaF2 nanocrystals for the fluorite and α-PbCl2-type phase are 103(2 and 78(2 GPa, which are both larger than those of the bulk CaF2. The CaF2 nanocrystals exhibit obviously higher incompressibility compare to bulk CaF2. Further analysis demonstrates that the defect effect in our CaF2 nanocrystals plays a dominant role in the structural stability.

  8. Ionospheric F2-Layer Semi-Annual Variation in Middle Latitude by Solar Activity

    Directory of Open Access Journals (Sweden)

    Yoon-Kyung Park

    2010-12-01

    Full Text Available We examine the ionospheric F2-layer electron density variation by solar activity in middle latitude by using foF2 observed at the Kokubunji ionosonde station in Japan for the period from 1997 to 2008. The semi-annual variation of foF2 shows obviously in high solar activity (2000-2002 than low solar activity (2006-2008. It seems that variation of geomagnetic activity by solar activity influences on the semi-annual variation of the ionospheric F2-layer electron density. According to the Lomb-Scargle periodogram analysis of foF2 and Ap index, interplanetary magnetic field (IMF Bs (IMF Bz <0 component, solar wind speed, solar wind number density and flow pressure which influence the geomagnetic activity, we examine how the geomagnetic activity affects the ionospheric F2-layer electron density variation. We find that the semi-annual variation of daily foF2, Ap index and IMF Bs appear clearly during the high solar activity. It suggests that the semi-annual variation of geomagnetic activity, caused by Russell-McPherron effect, contributes greatly to the ionospheric F2-layer semi-annual electron density variation, except dynamical effects in the thermosphere.

  9. Effect of high-energy electron irradiation in an electron microscope column on fluorides of alkaline earth elements (CaF2, SrF2, and BaF2)

    International Nuclear Information System (INIS)

    Nikolaichik, V. I.; Sobolev, B. P.; Zaporozhets, M. A.; Avilov, A. S.

    2012-01-01

    The effect of high-energy (150 eV) electron irradiation in an electron microscope column on crystals of fluorides of alkaline earth elements CaF 2 , SrF 2 , and BaF 2 is studied. During structural investigations by electron diffraction and electron microscopy, the electron irradiation causes chemical changes in MF 2 crystals such as the desorption of fluorine and the accumulation of oxygen in the irradiated area with the formation of oxide MO. The fluorine desorption rate increases significantly when the electron-beam density exceeds the threshold value of ∼2 × 10 3 pA/cm 2 ). In BaF 2 samples, the transformation of BaO into Ba(OH) 2 was observed when irradiation stopped. The renewal of irradiation is accompanied by the inverse transformation of Ba(OH) 2 into BaO. In the initial stage of irradiation of all MF 2 compounds, the oxide phase is in the single-crystal state with a lattice highly matched with the MF 2 matrix. When the irradiation dose is increased, the oxide phase passes to the polycrystalline phase. Gaseous products of MF 2 destruction (in the form of bubbles several nanometers in diameter) form a rectangular array with a period of ∼20 nm in the sample.

  10. Oxidation characteristics of MgF2 in air at high temperature

    Science.gov (United States)

    Chen, H. K.; Jie, Y. Y.; Chang, L.

    2017-02-01

    High temperature oxidation properties of MgF2 in air were studied. The changes of phase composition, macro surface morphology, weight and elemental composition of MgF2 samples with temperature were investigated by using XRD, EDS and gravimetric analyses. The results show that the oxidation reaction of MgF2 converted to MgO occurred at high temperature, and the reaction was accelerated by the increase of temperature and the presence of impurities. This result clarifies the understanding of the high temperature oxidation behavior of MgF2 in air, and provides a theoretical basis for the reasonable application of MgF2 in optical coating materials, electronic ceramic materials and magnesium melt protection.

  11. Comportamiento productivo en híbridos de jitomate y sus respectivas poblaciones F2

    Directory of Open Access Journals (Sweden)

    J. Martínez-Solís

    2005-01-01

    Full Text Available Debido a que el precio de semilla híbrida de jitomate es muy alto, muchos agricultores utilizan generaciones F2 en parcelas comerciales. Por esta razón con el propósito de evaluar el comportamiento entre genotipos de jitomate F1 y F2, 37 híbridos y sus respectivas generaciones F2 fueron establecidos en invernadero. La mayoría de las generaciones F2 presentaron menor peso total de fruto por planta y número de frutos por planta con respecto a sus F1; sin embargo, el efecto fue estadísticamente significativo sólo en dos genotipos tipo bola de hábito de crecimiento determinado y cuatro genotipos tipo bola de hábito de crecimiento indeterminado, los cuales abatieron su producción de fruto de F2 en al menos 20 %

  12. Thermal expansion coefficients of obliquely deposited MgF2 thin films and their intrinsic stress.

    Science.gov (United States)

    Jaing, Cheng-Chung

    2011-03-20

    This study elucidates the effects of columnar angles and deposition angles on the thermal expansion coefficients and intrinsic stress behaviors of MgF2 films with columnar microstructures. The behaviors associated with temperature-dependent stresses in the MgF2 films are measured using a phase-shifting Twyman-Green interferometer with a heating stage and the application of a phase reduction algorithm. The thermal expansion coefficients of MgF2 films at various columnar angles were larger than those of glass substrates. The intrinsic stress in the MgF2 films with columnar microstructures was compressive, while the thermal stress was tensile. The thermal expansion coefficients of MgF2 films with columnar microstructures and their intrinsic stress evidently depended on the deposition angle and the columnar angle.

  13. Synthesis and X-ray crystal structure of (OsO(3)F(2))(2)2XeOF(4) and the Raman spectra of (OsO(3)F(2))(infinity), (OsO(3)F(2))(2), and (OsO(3)F(2))(2)2XeOF(4).

    Science.gov (United States)

    Hughes, Michael J; Mercier, Hélène P A; Schrobilgen, Gary J

    2009-05-18

    The adduct, (OsO(3)F(2))(2)2XeOF(4), was synthesized by dissolution of the infinite chain polymer, (OsO(3)F(2))(infinity), in XeOF(4) solvent at room temperature followed by removal of excess XeOF(4) under dynamic vacuum at 0 degrees C. Continued pumping at 0 degrees C resulted in removal of associated XeOF(4), yielding (OsO(3)F(2))(2), a new low-temperature phase of OsO(3)F(2). Upon standing at 25 degrees C for 1(1)/(2) h, (OsO(3)F(2))(2) underwent a phase transition to the known monoclinic phase, (OsO(3)F(2))(infinity). The title compounds, (OsO(3)F(2))(infinity), (OsO(3)F(2))(2), and (OsO(3)F(2))(2)2XeOF(4) have been characterized by low-temperature (-150 degrees C) Raman spectroscopy. Crystallization of (OsO(3)F(2))(2)2XeOF(4) from XeOF(4) solution at 0 degrees C yielded crystals suitable for X-ray structure determination. The structural unit contains the (OsO(3)F(2))(2) dimer in which the OsO(3)F(3) units are joined by two Os---F---Os bridges having fluorine bridge atoms that are equidistant from the osmium centers (2.117(5) and 2.107(4) A). The dimer coordinates to two XeOF(4) molecules through Os-F...Xe bridges in which the Xe...F distances (2.757(5) A) are significantly less than the sum of the Xe and F van der Waals radii (3.63 A). The (OsO(3)F(2))(2) dimer has C(i) symmetry in which each pseudo-octahedral OsO(3)F(3) unit has a facial arrangement of oxygen ligands with XeOF(4) molecules that are only slightly distorted from their gas-phase C(4v) symmetry. Quantum-chemical calculations using SVWN and B3LYP methods were employed to calculate the gas-phase geometries, natural bond orbital analyses, and vibrational frequencies of (OsO(3)F(2))(2), (OsO(3)F(2))(2)2XeOF(4), XeOF(4), OsO(2)F(4), and (mu-FOsO(3)F(2))(2)OsO(3)F(-) to aid in the assignment of the experimental vibrational frequencies of (OsO(3)F(2))(2), (OsO(3)F(2))(2)2XeOF(4), and (OsO(3)F(2))(infinity). The vibrational modes of the low-temperature polymeric phase, (OsO(3)F(2))(infinity), have been

  14. Accumulation of enriched uranium UO2F2 in ultrastructure as studied by electron microscopic autoradiography

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Wang Yuanchang

    1992-01-01

    A study was made on the retention of soluble enriched uranium UO 2 F 2 in ultrastructure by electron microscopic autoradiography. The early dynamic accumulation of radioactivity in the body showed that enriched uranium UO 2 F 2 was mainly localized in kidneys, especially accumulated in epithelial cells of proximal convoluted tubules leading to degeneration and necrosis of the tubules. In liver cells, enriched uranium UO 2 F 2 at first deposited in nuclei of the cells and in soluble proteins of the plasma, and later accumulated selectively in mitochondria and lysosomes. On electron microscopic autoradiographic study it was shown that the dynamic retention of radioactivity of enriched uranium UO 2 F 2 in skeleton increased steadily through the time period of exposure. Enriched uranium UO 2 F 2 chiefly deposited in nuclei and mitochondria of osteoblasts as well as of osteoclasts

  15. Media for identification of Gibberella zeae and production of F-2-(Zearalenone).

    Science.gov (United States)

    Bacon, C W; Robbins, J D; Porter, J K

    1977-02-01

    Media are described for the isolaton of Fusarium graminearum in the perithecial state, Gibberella zeae, and for the production of F-2 (zearalenone) by Fusarium species. On soil extract-corn meal agar isolated medium, G. Zeae produced perithecia in 9 to 14 days under a 12-h photoperiod. Species of Fusarium were screened for F-2 production on a liquid medium. From strains that produced F-2, the yields, from stationary cultures of G. zeae and F. culmorum after 12 days of incubation, ranged from 22 to 86 mg/liter. Three strains produced no F-2. Glumatic acid, starch, yeast extract,and the proper ratio of medium volume-to-flask volume were necessary for F-2 synthesis.

  16. Fabrication and spectral properties of Nd, La: CaF2 transparent ceramics

    Science.gov (United States)

    Xie, Xiaoyu; Mei, Bingchu; Song, Jinghong; Li, Weiwei; Su, Liangbi

    2018-02-01

    1 at.% Nd: CaF2 nanoparticles doped with different concentrations of La3+ ions (from 0 to 5 at.%) were synthesized by co-precipitation method. Phase identification, morphology of the nanoparticles were investigated by XRD and SEM measurements. The Nd, La: CaF2 ceramics were fabricated by hot-pressed method in the vacuum environment. The transmittance of all the ceramics reached 88% at the wavelength of 1400 nm. The luminescence intensities and decay lifetimes enhanced significantly with the increasing of La3+ concentration. The Nd, La: CaF2 ceramics have broad and flat emission band at 1050 nm with the largest FWHM of 28.16 nm. In addition, the spectrum results indicated that the fluorescence lifetime of Nd, La: CaF2 ceramics was longer than that of the Nd, Y: CaF2 ceramics with the same doping concentration.

  17. Ginsenoside F2 reduces hair loss by controlling apoptosis through the sterol regulatory element-binding protein cleavage activating protein and transforming growth factor-β pathways in a dihydrotestosterone-induced mouse model.

    Science.gov (United States)

    Shin, Heon-Sub; Park, Sang-Yong; Hwang, Eun-Son; Lee, Don-Gil; Mavlonov, Gafurjon Turdalievich; Yi, Tae-Hoo

    2014-01-01

    This study was conducted to test whether ginsenoside F2 can reduce hair loss by influencing sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP) and the transforming growth factor beta (TGF-β) pathway of apoptosis in dihydrotestosterone (DHT)-treated hair cells and in a DHT-induced hair loss model in mice. Results for ginsenoside F2 were compared with finasteride. DHT inhibits proliferation of hair cells and induces androgenetic alopecia and was shown to activate an apoptosis signal pathway both in vitro and in vivo. The cell-based 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the proliferation rates of DHT-treated human hair dermal papilla cells (HHDPCs) and HaCaTs increased by 48% in the ginsenoside F2-treated group and by 12% in the finasteride-treated group. Western blot analysis showed that ginsenoside F2 decreased expression of TGF-β2 related factors involved in hair loss. The present study suggested a hair loss related pathway by changing SCAP related apoptosis pathway, which has been known to control cholesterol metabolism. SCAP, sterol regulatory element-binding protein (SREBP) and caspase-12 expression in the ginsenoside F2-treated group were decreased compared to the DHT and finasteride-treated group. C57BL/6 mice were also prepared by injection with DHT and then treated with ginsenoside F2 or finasteride. Hair growth rate, density, thickness measurements and tissue histotological analysis in these groups suggested that ginsenoside F2 suppressed hair cell apoptosis and premature entry to catagen more effectively than finasteride. Our results indicated that ginsenoside F2 decreased the expression of TGF-β2 and SCAP proteins, which have been suggested to be involved in apoptosis and entry into catagen. This study provides evidence those factors in the SCAP pathway could be targets for hair loss prevention drugs.

  18. One- and two-photon spectra of Nd3+ clusters in CaF2 and SrF2 crystals

    International Nuclear Information System (INIS)

    Basiev, Tasoltan T; Voronov, Valerii V; Glotova, M Yu; Papashvili, A G; Karasik, Aleksandr Ya

    2003-01-01

    The polarised two-photon (IR) and one-photon (visible) luminescence excitation spectra of Nd 3+ nanoclusters in CaF 2 and SrF 2 crystals are measured at 10 K using a F - 2 :LiF colour centre laser tunable in spectral ranges 1090 - 1230 nm and 545 - 615 nm with an emission linewidth of ∼0.02 - 0.03 cm -1 , an average output power of ∼55 mW, and a pulse repetition rate of 10 Hz. The two-photon excitation spectra at the 4 I 9/2 → 4 G 5/2 transition reveal the structure, which is absent upon one-photon excitation, which can be explained by different selection rules for some Stark - Stark transitions upon one- and two-photon absorption. (special issue devoted to the memory of academician a m prokhorov)

  19. Aspects of the production of 18F-2-deoxy-2-fluoro-D-glucose via 18F2 with a tandem Van de Graaf accelerator

    International Nuclear Information System (INIS)

    Shaughnessy, W.J.; Gatley, S.J.; Hichwa, R.D.; Lieberman, L.M.; Nickles, R.J.

    1981-01-01

    During deuteron irradiation of 100 psig neon containing 1-2% of elemental fluorine, the induced 18 F partitions into three main fractions. About 50% remains in the passivated nickel target after elution of the gas mixture. Some of the gaseous 18 F is capable of performing fluorination reactions and is presumed to be 18 F 2 : the rest is a mixture of at least two unreactive gases, one of which behaves on gas chromatography like CF 4 . The ratio of reactive to unreactive gaseous 18 F decreases with longer irradiation times but increases when the target gas is cooled to -30C during bombardment. Reaction of the presumed 18 F 2 with 4.5,6-triacetyl-D-glucal, essentially by the published method, yielded 18 F-2-deoxy-2-fluoro-4,5,6-triacetyl-x-D-glucosyl fluoride and the corresponding β-D-mannosyl fluoride. These were separated either by column chromatography or preparative TLC, using plates with a pre-absorbent layer. Hydrolysis of the glucoyl fluoride gave 18 F-2-deoxy-2-fluoro-D-glucose ( 18 F-2FDG) with a decay-corrected yield of about 10% based on 18 F trapped by the triacetylglucal. The 60 min organ distribution of 18 F from 18 F-2-FDG in tumor bearing rats was compared with the corresponding distribution after administration of 18 F-3-deoxy-3-fluoro-D-glucose ( 18 F-3FDG). Organ/blood ratios were uniformly higher for 18 F-2FDG than for no carrier added 18 F-3FDG; only heart, brain and thyroid had ratios greater than unity. Added carrier 3-FDG further lowered organ/blood ratios. The main conclusion drawn from this animal work is that 18 F-3FDG is unlikely to rival 18 F-2FDG for nuclear medicine studies, where high target /blood ratios (obtained by metabolic trapping as the sugar-6-phosphate) are necessary. However 18 F-3FDG may be useful for estimating the concentration of free glucose in organs if further work confirms that it is an essentially non-metabolized analog of glucose. (author)

  20. Pre-storm NmF2 enhancements at middle latitudes: delusion or reality?

    Directory of Open Access Journals (Sweden)

    A. V. Mikhailov

    2009-03-01

    Full Text Available A critical analysis of recent publications devoted to the NmF2 pre-storm enhancements is performed. There are no convincing arguments that the observed cases of NmF2 enhancements at middle and sub-auroral latitudes bear a relation to the following magnetic storms. In all cases considered the NmF2 pre-storm enhancements were due to previous geomagnetic storms, moderate auroral activity or they presented the class of positive quiet time events (Q-disturbances. Therefore, it is possible to conclude that there is no such an effect as the pre-storm NmF2 enhancement as a phenomenon inalienably related to the following magnetic storm. The observed nighttime NmF2 enhancements at sub-auroral latitudes may result from plasma transfer from the plasma ring area by meridional thermospheric wind. Enhanced plasmaspheric fluxes into the nighttime F2-region resulted from westward substorm-associated electric fields is another possible source of nighttime NmF2 enhancements. Daytime positive Q-disturbances occurring under very low geomagnetic activity level may be related to the dayside cusp activity.

  1. Plasma 8-iso-Prostaglandin F2α concentrations and outcomes after acute intracerebral hemorrhage.

    Science.gov (United States)

    Du, Quan; Yu, Wen-Hua; Dong, Xiao-Qiao; Yang, Ding-Bo; Shen, Yong-Feng; Wang, Hao; Jiang, Li; Du, Yuan-Feng; Zhang, Zu-Yong; Zhu, Qiang; Che, Zhi-Hao; Liu, Qun-Jie

    2014-11-01

    Higher plasma 8-iso-Prostaglandin F2α concentrations have been associated with poor outcome of severe traumatic brain injury. We further investigated the relationships between plasma 8-iso-Prostaglandin F2α concentrations and clinical outcomes in patients with acute intracerebral hemorrhage. Plasma 8-iso-Prostaglandin F2α concentrations of 128 consecutive patients and 128 sex- and gender-matched healthy subjects were measured by enzyme-linked immunosorbent assay. We assessed their relationships with disease severity and clinical outcomes including 1-week mortality, 6-month mortality and unfavorable outcome (modified Rankin Scale score>2). Plasma 8-iso-Prostaglandin F2α concentrations were substantially higher in patients than in healthy controls. Plasma 8-iso-Prostaglandin F2α concentrations were positively associated with National Institutes of Health Stroke Scale (NIHSS) scores and hematoma volume using a multivariate linear regression. It emerged as an independent predictor for clinical outcomes of patients using a forward stepwise logistic regression. ROC curves identified the predictive values of plasma 8-iso-Prostaglandin F2α concentrations, and found its predictive value was similar to NIHSS scores and hematoma volumes. However, it just numerically added the predictive values of NIHSS score and hematoma volume. Increased plasma 8-iso-Prostaglandin F2α concentrations are associated with disease severity and clinical outcome after acute intracerebral hemorrhage. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Epitaxial growth of lithium fluoride on the (1 1 1) surface of CaF 2

    Science.gov (United States)

    Klumpp, St; Dabringhaus, H.

    1999-08-01

    Growth of lithium fluoride by molecular beam epitaxy on the (1 1 1) surface of calcium fluoride crystals was studied by TEM and LEED for crystal temperatures from 400 to 773 K and impinging lithium fluoride fluxes from 3×10 11 to 3×10 14 cm -2 s -1. Growth starts, usually, at the steps on the (1 1 1) surface of CaF 2. For larger step distances and at later growth stages also growth on the terraces between the steps is found. Preferably, longish, roof-like crystallites are formed, which can be interpreted by growth of LiF(2 0 1¯)[0 1 0] parallel to CaF 2(1 1 1)[ 1¯ 0 1]. To a lesser extent square crystallites, i.e. growth with LiF(0 0 1), and, rarely, three-folded pyramidal crystallites, i.e. growth with LiF(1 1 1) parallel to CaF 2(1 1 1), are observed. While the pyramidal crystallites show strict epitaxial orientation with LiF[ 1¯ 0 1]‖CaF 2[ 1¯ 0 1] and LiF[ 1¯ 0 1]‖CaF 2[1 2¯ 1], only about 80% of the square crystallites exhibit an epitaxial alignment, where LiF[1 0 0]‖CaF 2[ 1¯ 0 1] is preferred to LiF[1 1 0]‖CaF 2[ 1¯ 0 1]. The epitaxial relationships are discussed on the basis of theoretically calculated adsorption positions of the lithium fluoride monomer and dimer on the terrace and at the steps of the CaF 2(1 1 1) surface.

  3. Theoretical characterization of the F(2)O(3) molecule by coupled-cluster methods.

    Science.gov (United States)

    Huang, Ming-Ju; Watts, John D

    2010-09-23

    Coupled-cluster calculations with extended basis sets that include noniterative connected triple excitations (CCSD(T)) have been used to study the FOOOF isomer of F(2)O(3). Second-order Moller-Plessett perturbation theory (MP2) and density-functional theory (B3LYP functional) calculations have also been performed for comparison. Two local minima of similar energy, namely, conformers of C(2) and C(s) symmetry have been located. Structures, harmonic vibrational frequencies, and standard enthalpies and free energies of formation have been calculated. The calculated bond lengths of F(2)O(3) are more characteristic of those in F(2)O and a "normal" peroxide than the unusual bond lengths in F(2)O(2). Both conformers have equal F-O and O-O bond lengths, contrary to a recent suggestion of an unsymmetrical structure. The harmonic vibrational frequencies can aid possible identification of gaseous F(2)O(3). The calculated Δ(f)H° and Δ(f)G° are 110 and 173 kJ mol(-1), respectively. These values are based on extrapolation of CCSD(T) results with augmented triple- and quadruple-ζ basis sets and are expected to be within chemical accuracy (i.e., 1 kcal mol(-1) or 4 kJ mol(-1)). F(2)O(3) is calculated to be stable to decomposition to either FO + FOO or F(2) + O(3), but unstable to decomposition to its elements, to F(2)O(2) + (1)/(2)O(2), and to F(2)O + O(2).

  4. Long-term trends in foF2: their estimating and origin

    Directory of Open Access Journals (Sweden)

    W. Wan

    2008-03-01

    Full Text Available This paper deals with two problems, methods of foF2 trend determination and origin of trends in foF2, both being controversial in current literature. We found that various regression-based methods and artificial neural network-based method of Yue et al. (2006 provided comparable results within uncertainties caused mainly by various ways of removing/suppressing the dominant solar cycle effect. The role of geomagnetic activity in the observed trends in foF2 was probably substantial and might be still even rather dominant in the last quarter of the 20th century.

  5. Optical annealing of CaF2:Mn for cooled optically stimulated luminescence

    International Nuclear Information System (INIS)

    Miller, S.D.; Stahl, K.A.; Endres, G.W.R.; McDonald, J.C.

    1989-01-01

    Optical annealing of the cooled optically stimulated luminescence in CaF 2 :Mn at room temperature has been demonstrated. The laser of choice for optical annealing of CaF 2 : Mn is a 326 nm helium-cadmium ultraviolet laser. A complete cycle of readout and annealing of the CaF 2 :Mn cooled optically stimulated dosemeters can now be accomplished without heating the dosemeters above room temperature. This annealing work represents the next step toward creating a proton-recoil-based fast neutron dosimetry system based on the cooled optically stimulated luminescence technique. (author)

  6. Short-Term fo F2 Forecast: Present Day State of Art

    Science.gov (United States)

    Mikhailov, A. V.; Depuev, V. H.; Depueva, A. H.

    An analysis of the F2-layer short-term forecast problem has been done. Both objective and methodological problems prevent us from a deliberate F2-layer forecast issuing at present. An empirical approach based on statistical methods may be recommended for practical use. A forecast method based on a new aeronomic index (a proxy) AI has been proposed and tested over selected 64 severe storm events. The method provides an acceptable prediction accuracy both for strongly disturbed and quiet conditions. The problems with the prediction of the F2-layer quiet-time disturbances as well as some other unsolved problems are discussed

  7. 4He adsorption and third-sound propagation on rough CaF2 surfaces

    International Nuclear Information System (INIS)

    Herrmann, J.C.; Hallock, R.B.

    2003-01-01

    We have investigated the propagation of third sound on well characterized rough CaF 2 surfaces as a function of 4 He film thickness. In addition we have measured the adsorption of 4 He to the CaF 2 surfaces using quartz crystal microbalances. We report values for the superfluid depletion thickness D for the three surfaces examined here. A model for the reduction of the third-sound speed due to the increased helium adsorption on rough CaF 2 is explored

  8. Screening of nuclear structure function F2A(x,Q2) at small x values

    International Nuclear Information System (INIS)

    Davidovs'kij, V.V.

    1999-01-01

    The U-matrix method have been applied to build an amplitude for virtual photon absorption by nuclei which satisfies unitarity.This amplitude have been utilised to obtain the expression for the structure function F 2A ,which is convenient to perform analytical calculations with.Profile functions of nuclei with Gauss,Woods-Saxon and constant density distribution have been considered.It is shown that effects of quark-antiquark pair rescattering in nucleus cause the screening of F 2A and the change of power-like behaviour of F 2A to logarithmic one at small x. Numerical estimations are given

  9. Atmospheric chemistry of n-CxF2x+1CHO (x = 1, 2, 3, 4)

    DEFF Research Database (Denmark)

    Hurley, M. D.; Ball, J. C.; Wallington, T. J.

    2006-01-01

    Smog chamber/FTIR techniques were used to study the atmospheric fate of n-C(x)F(2)(x)(+1)C(O) (x = 1, 2, 3, 4) radicals in 700 Torr O(2)/N(2) diluent at 298 +/- 3 K. A competition is observed between reaction with O(2) to form n-C(x)()F(2)(x)()(+1)C(O)O(2) radicals and decomposition to form n-C(x...... to the atmospheric chemistry of n-C(x)F(2)(x)(+1)C(O) radicals and their possible role in contributing to the formation of perfluorocarboxylic acids in the environment....

  10. Observation of ultraslow stress release in silicon nitride films on CaF2

    International Nuclear Information System (INIS)

    Guo, Tianyi; Deen, M. Jamal; Xu, Changqing; Fang, Qiyin; Selvaganapathy, P. Ravi; Zhang, Haiying

    2015-01-01

    Silicon nitride thin films are deposited by plasma-enhanced chemical vapor deposition on (100) and (111) CaF 2 crystalline substrates. Delaminated wavy buckles formed during the release of internal compressive stress in the films and the stress releasing processes are observed macroscopically and microscopically. The stress release patterns start from the substrate edges and propagate to the center along defined directions aligned with the crystallographic orientations of the substrate. The stress releasing velocity of SiN x film on (111) CaF 2 is larger than that of SiN x film with the same thickness on (100) CaF 2 . The velocities of SiN x film on both (100) and (111) CaF 2 increase with the film thickness. The stress releasing process is initiated when the films are exposed to atmosphere, but it is not a chemical change from x-ray photoelectron spectroscopy

  11. Measurements of CaF2 concentration in fluorite ore using thermoluminescence techniques

    International Nuclear Information System (INIS)

    Lembo, L.; Maestri, G.; Pimpinella, M.; Benzi, V.; Muntoni, C.

    1990-01-01

    Fluorite powder is produced by means of a flotation process on crude ore extracted by the mines. A full automation of the flotation plant would reduce the operating cost and improve the quality and recovery of fluorite production. However, taking into account that the efficiency of a flotation cycle is directly dependent on the CaF 2 content in the concentrate and tail products, this automation requires a quasi-real-time quantitative analysis of CaF 2 concentration in the floated pulp. The feasibility was studied of using a thermoluminescence technique as an on-line analysis method to measure the CaF 2 concentration during the flotation cycle. A first set of experimental conditions to determine CaF 2 content in acid-grade fluorspar has been already developed and the preliminary results so far obtained are presented. (author)

  12. Theoretical study of the F2 molecule using the variational cellular method

    International Nuclear Information System (INIS)

    Lima, M.A.P.; Leite, J.R.; Fazzio, A.

    1981-02-01

    Variational Cellular Method calculations for F 2 have been carried out at several internuclear distances. The ground and excited state potential curves are presented. The overall agreement between the VCM results and ab initio calculations is fairly good. (Author) [pt

  13. Isolation and characterization of a thermolysin peptide containing acetyllysine from enzymatically acetylated f2al histone

    International Nuclear Information System (INIS)

    Horiuchi, Kentaro; Fujimoto, Daisaburo

    1973-01-01

    Previous studies (vol. 72, 433, '72) in this laboratory showed that histone acetylase in the cytosol of calf thymus introduced acetyl groups primarily into the epsilon-amino groups of lysine residues in a histone fraction, f2al. In an attempt to examine the site of acetylation in f2al by the enzyme, 14 C-acetylated f2al was isolated and digested by thermolysin. A radioactive peptide, which accounted for 50 - 60% of the total radioactivity, was obtained from the thermolysin digest and identified as the fragment containing amino acid residues 10-21. It appears, therefore, that the major sites of acetylation by the enzyme are the lysine 12 or 16 or both, which are known to be acetylated in vivo. It was also shown that the peptide was not deacetylated by histone deacetylase, in contrast with the whole f2al molecule. (author)

  14. Behavioral and spermatogenic hybrid male breakdown in Nasonia.

    Science.gov (United States)

    Clark, M E; O'Hara, F P; Chawla, A; Werren, J H

    2010-03-01

    Several reproductive barriers exist within the Nasonia species complex, including allopatry, premating behavioral isolation, postzygotic inviability and Wolbachia-induced cytoplasmic incompatibility. Here we show that hybrid males suffer two additional reproductive disadvantages, an inability to properly court females and decreased sperm production. Hybrid behavioral sterility, characterized by a reduced ability of hybrids to perform necessary courtship behaviors, occurs in hybrids between two species of Nasonia. Hybrid males produced in crosses between N. vitripennis and N. giraulti courted females at a reduced frequency (23-69%), compared with wild-type N. vitripennis and N. giraulti males (>93%). Reduced courtship frequency was not a simple function of inactivity among hybrids. A strong effect of cytoplasmic (mitochondrial) background was also found in N. vitripennis and N. giraulti crosses; F2 hybrids with giraulti cytoplasm showing reduced ability at most stages of courtship. Hybrids produced between a younger species pair, N. giraulti and N. longicornis, were behaviorally fertile. All males possessed motile sperm, but sperm production is greatly reduced in hybrids between the older species pair, N. vitripennis and N. giraulti. This effect on hybrid males, lowered sperm counts rather than nonfunctional sperm, is different from most described cases of hybrid male sterility, and may represent an earlier stage of hybrid sperm breakdown. The results add to previous studies of F2 hybrid inviability and behavioral sterility, and indicate that Wolbachia-induced hybrid incompatibility has arisen early in species divergence, relative to behavioral sterility and spermatogenic infertility.

  15. Behavioural and spermatogenic hybrid male breakdown in Nasonia

    Science.gov (United States)

    Clark, Michael E.; O’Hara, F. Patrick; Chawla, Ankur; Werren, John H.

    2010-01-01

    Several reproductive barriers exists within the Nasonia species complex, including allopatry, premating behavioural isolation, postzygotic inviability and Wolbachia-induced cytoplasmic incompatibility. Here we show that hybrid males suffer two additional reproductive disadvantages, an inability to properly court females and decreased sperm production. Hybrid behavioural sterility, characterized by a reduced ability of hybrids to perform necessary courtship behaviours, occurs in hybrids between two species of Nasonia. Hybrid males produced in crosses between N. vitripennis and N. giraulti courted females at a reduced frequency (23-69%), compared to wild-type N. vitripennis and N. giraulti males (>93%). Reduced courtship frequency was not a simple function of inactivity among hybrids. A strong effect of cytoplasmic (mitochondrial) background was also found in N. vitripennis and N. giraulti crosses; F2 hybrids with giraulti cytoplasm showing reduced ability at most stages of courtship. Hybrids produced between a younger species pair, N. giraulti and N. longicornis, were behaviourally fertile. All males possessed motile sperm, but sperm production is greatly reduced in hybrids between the older species pair, N. vitripennis and N. giraulti. This effect on hybrid males, lowered sperm counts rather than non-functional sperm, is different from most described cases of hybrid male sterility and may represent an earlier stage of hybrid sperm breakdown. The results add to previous studies of F2 hybrid inviability and behavioural sterility, and indicated that Wolbachia induced hybrid incompatibility has arisen early in species divergence, relative to behavioural sterility and spermatogenic infertility. PMID:20087395

  16. Thailand low and equatorial F 2-layer peak electron density and comparison with IRI-2007 model

    Science.gov (United States)

    Wichaipanich, N.; Supnithi, P.; Tsugawa, T.; Maruyama, T.

    2012-06-01

    Ionosonde measurements obtained at two Thailand ionospheric stations, namely Chumphon (10.72°N, 99.37°E, dip 3.0°N) and Chiang Mai (18.76°N, 98.93°E, dip 12.7°N) are used to examine the variation of the F 2-layer peak electron density ( N m F 2) which is derived from the F 2-layer critical frequency, f o f 2. Measured data from September 2004 to August 2005 (a period of low solar activity) are analyzed based on the diurnal and seasonal variation and then compared with IRI-2007 model predictions. Our results show that, in general, the diurnal and seasonal variations of the N m F 2 predicted by the IRI (URSI and CCIR options) model show a feature generally similar to the observed N m F 2. Underestimation mostly occurs in all seasons except during the September equinox and the December solstice at Chumphon, and the September equinox and the March equinox at Chiang Mai, when they overestimate those measured. The best agreement between observation and prediction occurs during the pre-sunrise to post-sunrise hours. The best agreement of the %PD values of both the options occurs during the March equinox, while the agreement is the worst during the September equinox. The N m F 2 values predicted by the CCIR option show a smaller range of deviation than the N m F 2 values predicted by the URSI option. During post-sunset to morning hours (around 21:00-09:00 LT), the observed N m F 2 at both stations are almost identical for the periods of low solar activity. However, during daytime, the observed N m F 2 at Chumphon is lower than that at Chiang Mai. The difference between these two stations can be explained by the equatorial ionospheric anomaly (EIA). These results are important for future improvements of the IRI model for N m F 2 over Southeast Asia, especially for the areas covered by Chumphon and Chiang Mai stations.

  17. Study of Photoionization and Fragmentation on CHClF2 : Experiments and Calculations

    International Nuclear Information System (INIS)

    Sheng, L.; Yang, B.; Huang, C.; Qi, F.; Zhang, Y.; Wang, Z.; Zhou, S.

    2004-01-01

    Full text: The photoionization and fragmentation of CHClF 2 are studied with VUV radiation and photoionization mass spectroscopy at NSRL. Ionization potential of Parent molecule CHClF 2 , appearance energies of some fragment ions, and dissociative energy of some fragmentation process are obtained from photoionization efficiency spectroscopy. Dissociative photoionization channels for formation of some fragment ions are proposed on comparison of determined appearance energies and energies predicted with Gaussian-98 calculation

  18. NLO predictions for the growth of F2 at small χ and comparison with experimental data

    International Nuclear Information System (INIS)

    Lopez, C.; Barreiro, F.; Yndurain, F.J.

    1996-05-01

    We present parametrizations for the proton structure function F 2 in the next to leading order in perturbative QCD. The calculations show that the dominant term to F 2 (x,Q 2 ) should grow as x -λ s for small x values, with the exponent λ S being essentially independent of Q 2 . Comparisons with the most recent H1 and ZEUS data confirm the value λ S ∼0.35 obtained previously from fits to low energy data. (orig.)

  19. On the Rise of the Proton Structure Function F_2 Towards Low x

    CERN Document Server

    Adloff, C.; Andrieu, B.; Anthonis, T.; Arkadov, V.; Astvatsatourov, A.; Babaev, A.; Bahr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bate, P.; Beglarian, A.; Behnke, O.; Beier, C.; Belousov, A.; Benisch, T.; Berger, Christoph; Berndt, T.; Bizot, J.C.; Boudry, V.; Braunschweig, W.; Brisson, V.; Broker, H.B.; Brown, D.P.; Bruckner, W.; Bruncko, D.; Burger, J.; Busser, F.W.; Bunyatyan, A.; Burrage, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cao, Jun; Caron, S.; Clarke, D.; Clerbaux, B.; Collard, C.; Contreras, J.G.; Coppens, Y.R.; Coughlan, J.A.; Cousinou, M.C.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Davidsson, M.; Delcourt, B.; Delerue, N.; Demirchyan, R.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dingfelder, J.; Dixon, P.; Dodonov, V.; Dowell, J.D.; Droutskoi, A.; Dubak, A.; Duprel, C.; Eckerlin, Guenter; Eckstein, D.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Ferron, S.; Fleischer, M.; Fleming, Y.H.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Foster, J.M.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Garvey, J.; Gassner, J.; Gayler, Joerg; Gerhards, R.; Gerlich, C.; Ghazaryan, Samvel; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goodwin, C.; Grab, C.; Grassler, H.; Greenshaw, T.; Grindhammer, Guenter; Hadig, T.; Haidt, D.; Hajduk, L.; Haynes, W.J.; Heinemann, B.; Heinzelmann, G.; Henderson, R.C.W.; Hengstmann, S.; Henschel, H.; Heremans, R.; Herrera, G.; Herynek, I.; Hildebrandt, M.; Hilgers, M.; Hiller, K.H.; Hladky, J.; Hoting, P.; Hoffmann, D.; Horisberger, R.; Hurling, S.; Ibbotson, M.; Issever, C .; Jacquet, M.; Jaffre, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jones, M.A.S.; Jung, H.; Kastli, H.K.; Kant, D.; Kapichine, M.; Karlsson, M.; Karschnick, O.; Keil, F.; Keller, N.; Kennedy, J.; Kenyon, I.R.; Kermiche, S.; Kiesling, Christian M.; Kjellberg, P.; Klein, M.; Kleinwort, C.; Kluge, T.; Knies, G.; Koblitz, B.; Kolya, S.D.; Korbel, V.; Kostka, P.; Kotelnikov, S.K.; Koutouev, R.; Koutov, A.; Krehbiel, H.; Kroseberg, J.; Kruger, K.; Kupper, A.; Kuhr, T.; Kurca, T.; Lahmann, R.; Lamb, D.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebailly, E.; Lebedev, A.; Leissner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindstroem, M.; List, B.; Lobodzinska, E.; Lobodzinski, B.; Loginov, A.; Loktionova, N.; Lubimov, V.; Luders, S.; Luke, D.; Lytkin, L.; Mahlke-Kruger, H.; Malden, N.; Malinovski, E.; Malinovski, I.; Maracek, R.; Marage, P.; Marks, J.; Marshall, R.; Martyn, H.U.; Martyniak, J.; Maxfield, S.J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Meyer, P.O.; Mikocki, S.; Milstead, D.; Mkrtchyan, T.; Mohr, R.; Mohrdieck, S.; Mondragon, M.N.; Moreau, F.; Morozov, A.; Morris, J.V.; Muller, K.; Murin, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, T.; Nellen, G.; Newman, Paul R.; Nicholls, T.C.; Niebergall, F.; Niebuhr, C.; Nix, O.; Nowak, G.; Olsson, J.E.; Ozerov, D.; Panassik, V.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Phillips, J.P.; Pitzl, D.; Poschl, R.; Potachnikova, I.; Povh, B.; Rabbertz, K.; Radel, G.; Rauschenberger, J.; Reimer, P.; Reisert, B.; Reyna, D.; Risler, C.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rusakov, S.; Rybicki, K.; Sankey, D.P.C.; Scheins, J.; Schilling, F.P.; Schleper, P.; Schmidt, D.; Schmidt, S.; Schmitt, S.; Schneider, M.; Schoeffel, L.; Schoning, A.; Schorner, T.; Schroder, V.; Schultz-Coulon, H.C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Chekelian, V.; Sheviakov, I.; Shtarkov, L.N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Solovev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Spitzer, H.; Stamen, R.; Stella, B.; Stiewe, J.; Straumann, U.; Swart, M.; Tasevsky, M.; Chernyshov, V.; Chetchelnitski, S.; Thompson, Graham; Thompson, P.D.; Tobien, N.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Turney, J.E.; Tzamariudaki, E.; Udluft, S.; Urban, Marcel; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vassilev, S.; Vazdik, Y.; Vichnevski, A.; Wacker, K.; Wallny, R.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Werner, C.; Werner, M.; Werner, N.; White, G.; Wiesand, S.; Wilksen, T.; Winde, M.; Winter, G.G.; Wissing, C.; Wobisch, M.; Wunsch, E.; Wyatt, A.C.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zomer, F.; Zsembery, J.; zur Nedden, M.

    2001-01-01

    A measurement of the derivative (d ln F_2 / d lnx)_(Q^2)= -lambda(x,Q^2) of the proton structure function F_2 is presented in the low x domain of deeply inelastic positron-proton scattering. For 5*10^(-5)=1.5 GeV^2, lambda(x,Q^2) is found to be independent of x and to increase linearly with ln(Q^2).

  20. Fading of LiF and CaF2:Dy

    International Nuclear Information System (INIS)

    Ben-Shachar, B.; German, U.; Weiser, G.

    1983-03-01

    The fading of LiF and CaF 2 :Dy was investigated and the results were compared to the literature. The effect of thermal annealing was studied in order to reduce the fading in both phosphors and to minimize the effects of the environment on CaF 2 :Dy. Minimizing the fading and knowing its time dependence make possible the exact personal and environmental dosimetry. (Author)

  1. Phosphorylation of protein synthesis initiation factor 2 (elF-2) in the yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Romero, D.P.

    1986-01-01

    Initiation Factor 2 (elF-2) in the yeast Saccharomyces cerevisiae is comprised of 3 subunits. The control of protein synthesis in mammalian cells have been shown to involve the phosphorylation of the small (alpha) subunit by a specific protein kinase. Phosphorylation results in an inhibition of protein synthesis. In order to determine whether or not an analogous system is operative in yeast, the phosphorylation state of the alpha subunit of elF-2 in Saccharomyces was determined during various growth and nongrowth conditions. Cells were radiolabelled with 32 P and 35 S, and the whole cell lysates were analyzed by two dimensional gel electrophoresis. These experiments revealed that the smallest subunit (alpha, M/sub r/ = 31,000) is a phosphoprotein in vivo under a variety of growth and nongrowth conditions. This is in direct contrast to the pattern exhibited in mammalian cells. The fact that the small subunit of elF-2 in yeast is phosphorylated under a variety of physiological conditions indicates that such a covalent modification is important for some aspects of elF-2 function. In order to investigate this problem further, a protein kinase that specifically labels the alpha subunit of elF-2 in vitro was isolated. The kinase is not autophosphorylating, utilizes ATP as a phosphate donor, phosphorylates an exogenous protein, casein, modifies serine residues in elF-2, is cyclic nucleotide-independent, and is strongly inhibited by heparin

  2. Fabrication and Sintering Behavior of Er:SrF2 Transparent Ceramics using Chemically Derived Powder

    Science.gov (United States)

    Liu, Jun; Liu, Peng; Wang, Jun; Xu, Xiaodong; Li, Dongzhen; Zhang, Jian; Nie, Xinming

    2018-01-01

    In this paper, we report the fabrication of high-quality 5 at. % Er3+ ions doped SrF2 transparent ceramics, the potential candidate materials for a mid-infrared laser-gain medium by hot-pressing at 700 °C for 40 h using a chemically-derived powder. The phase structure, densification, and microstructure evolution of the Er:SrF2 ceramics were systematically investigated. In addition, the grain growth kinetic mechanism of Er:SrF2 was clarified. The results showed lattice diffusion to be the grain growth mechanism in the Er:SrF2 transparent ceramic of which highest in-line transmittance reached 92% at 2000 nm, i.e., very close to the theoretical transmittance value of SrF2 single crystal. Furthermore, the emission spectra showed that the strongest emission band was located at 2735 nm. This means that it is possible to achieve a laser output of approximately 2.7 μm in the 5 at. % Er3+ ions doped SrF2 transparent ceramics. PMID:29565322

  3. Fabrication and Sintering Behavior of Er:SrF2 Transparent Ceramics using Chemically Derived Powder

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2018-03-01

    Full Text Available In this paper, we report the fabrication of high-quality 5 at. % Er3+ ions doped SrF2 transparent ceramics, the potential candidate materials for a mid-infrared laser-gain medium by hot-pressing at 700 °C for 40 h using a chemically-derived powder. The phase structure, densification, and microstructure evolution of the Er:SrF2 ceramics were systematically investigated. In addition, the grain growth kinetic mechanism of Er:SrF2 was clarified. The results showed lattice diffusion to be the grain growth mechanism in the Er:SrF2 transparent ceramic of which highest in-line transmittance reached 92% at 2000 nm, i.e., very close to the theoretical transmittance value of SrF2 single crystal. Furthermore, the emission spectra showed that the strongest emission band was located at 2735 nm. This means that it is possible to achieve a laser output of approximately 2.7 μm in the 5 at. % Er3+ ions doped SrF2 transparent ceramics.

  4. Synthesis and characterization of Er3+ doped CaF2 nanoparticles

    International Nuclear Information System (INIS)

    Zhi Guanglin; Song Jinghong; Mei Bingchu; Zhou Weibing

    2011-01-01

    Highlights: → Er 3+ :CaF 2 nanoparticles were synthesized by co-precipitation method with particle size of 8-36 nm. → Increasing dopant concentration increases lattice constants and decreases grain size. → Annealing treatment has a remarkable effect on luminescence properties. → Luminescence intensity decrease with the increasing of the dopant concentration. - Abstract: Er 3+ doped CaF 2 nanoparticles were synthesized by a chemical co-precipitation method. Effect of the dopant concentrations on the structure and optical properties of the CaF 2 nanoparticles was investigated. The X-ray powder diffraction and transmission electron microscopy analysis was used to characterize the structure and morphology of the nanoparticles. The nanoparticles with different dopant concentration exhibited a sphere-like morphology with diameters of about 8-36 nm. The incorporation of Er 3+ ions into CaF 2 resulted in the decrease in grain size and deterioration of crystallinity, but enlarged the lattice constants of CaF 2 . Additional annealing treatment at 400 deg. C to the prepared CaF 2 removed the NO 3 - and OH - groups adsorbed on the particles' surfaces, and improved the optical properties of the nanoparticles. The fluorescence intensity, with a maximum at approximately 0.4 mol%, decreased with the increase in doping concentration because of concentration quenching.

  5. Evolution and Virulence of Influenza A Virus Protein PB1-F2

    Directory of Open Access Journals (Sweden)

    Ram P. Kamal

    2017-12-01

    Full Text Available PB1-F2 is an accessory protein of most human, avian, swine, equine, and canine influenza A viruses (IAVs. Although it is dispensable for virus replication and growth, it plays significant roles in pathogenesis by interfering with the host innate immune response, inducing death in immune and epithelial cells, altering inflammatory responses, and promoting secondary bacterial pneumonia. The effects of PB1-F2 differ between virus strains and host species. This can at least partially be explained by the presence of multiple PB1-F2 sequence variants, including premature stop codons that lead to the expression of truncated PB1-F2 proteins of different lengths and specific virulence-associated residues that enhance susceptibility to bacterial superinfection. Although there has been a tendency for human seasonal IAV to gradually reduce the number of virulence-associated residues, zoonotic IAVs contain a reservoir of PB1-F2 proteins with full length, virulence-associated sequences. Here, we review the molecular mechanisms by which PB1-F2 may affect influenza virulence, and factors associated with the evolution and selection of this protein.

  6. Reconstruction of missed critical frequency of F2-layer over Mexico using TEC

    Science.gov (United States)

    Sergeeva, M. A.; Maltseva, O. A.; Gonzalez-Esparza, A.; Romero Hernandez, E.; De la Luz, V.; Rodriguez-Martinez, M. R.

    2016-12-01

    The study of the Earth's ionosphere's state is one of the key issues within the Space Weather monitoring task. It is hard to overestimate the importance of diagnostics of its current state and forecasts of Space Weather conditions. There are different methods of short-time predictions for the ionosphere state change. The real-time monitoring of the ionospheric Total Electron Content (TEC) provides the opportunity to choose an appropriate technique for the particular observation point on the Earth. From September 2015 the continuous monitoring of TEC variations over the territory of Mexico is performed by the Mexican Space Weather Service (SCiESMEX). Regular patterns of the diurnal and seasonal TEC variations were revealed in base of past statistics and real-time observations which can be used to test the prediction method. Some specific features of the ionosphere behaviour are discussed. However, with all the merits of TEC as an ionospheric parameter, for the full picture of the processes in the ionosphere and for practical applications it is needed to identify the behaviour of other principal ionospheric parameters provided by ionosondes. Currently, SCiESMEX works on the project of the ionosonde installation in Mexico. This study was focused on the reconstruction of the critical frequency of F2-layer of the ionosphere (foF2) when this data is missing. For this purpose measurements of TEC and the median value of the equivalent slab thickness of the ionosphere were used. First, the foF2 values reconstruction was made for the case of the ionosonde data being absent during some hours or days. Second, the possibility of foF2 reconstruction was estimated for the Mexican region having no ionosonde using local TEC data and foF2 data obtained in the regions close to Mexico. Calculations were performed for quiet and disturbed periods. The results of reconstruction were compared to the foF2 obtained from the International Reference Model and to median foF2 values. Comparison

  7. On the application of CaF2:Eu and SrF2:Eu phosphors in LED based phototherapy lamp

    Science.gov (United States)

    Belsare, P. D.; Moharil, S. V.; Joshi, C. P.; Omanwar, S. K.

    2013-06-01

    In the last few years the interest of scientific community has been increased towards solid state lighting based on LEDs because of their superior advantages over the conventional fluorescent lamps. As the GaN based LEDs are easily available efforts of the researchers are now on making the new phosphors which are excitable in the near UV region (360-400nm) for solid state lighting. This paper reports the photoluminescence characteristics of CaF2:Eu and SrF2:Eu phosphor prepared by wet chemical method. The violet emission of these phosphors with near UV excitation can be useful in making a phototherapy lamp based on LEDs for treating various skin diseases like acne vulgaris and hyperbilirubinemia.

  8. Crystal structure of difluorochloronium hexafluoroniobate and hexafluorotantalate, ClF2NbF6 and ClF2TaF6

    International Nuclear Information System (INIS)

    Ehllern, A.M.; Antipin, M.Yu.; Sharabarin, A.V.; Struchkov, Yu.T.

    1991-01-01

    Crystal structure of ClF 2 NbF 6 (1) and ClF 2 TaF 6 (2) were investigated by the method of X-ray diffraction analysis. Salts 1 and 2 are isostructural, crystals are rhombic: a = 9.981(2) and 10.049(2), b = 5.781(1) and 5.775(1), c = 10.552(2) and 10.670(2) A, V = 608.9(3) and 619.2(3) A 3 , Z = 4, d calcd 3.058 and 3.952 g/cm 3 , sp. gr. Pcca. Both salts are characterized by ionic structure. Bond lengths and valent angles, general view of 1 crystal structure are presented

  9. Measurement of F_2^ccbar and F_2^bbbar at High Q^2 using the H1 Vertex Detector at HERA

    CERN Document Server

    Aktas, A.; Anthonis, T.; Aplin, S.; Asmone, A.; Babaev, A.; Backovic, S.; Bahr, J.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, Ch.; Berger, N.; Berndt, T.; Bizot, J.C.; Bohme, J.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Broker, H.-B.; Brown, D.P.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Caron, S.; Cassol-Brunner, F.; Cerny, K.; Chekelian, V.; Contreras, J.G.; Coppens, Y.R.; Coughlan, J.A.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Delcourt, B.; Demirchyan, R.; De Roeck, A.; Desch, K.; De Wolf, E.A.; Diaconu, C.; Dingfelder, J.; Dodonov, V.; Dubak, A.; Duprel, C.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Ellerbrock, M.; Elsen, E.; Erdmann, W.; Essenov, S.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Finke, L.; Fleischer, M.; Fleischmann, P.; Fleming, Y.H.; Flucke, G.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Franke, G.; Frising, G.; Frisson, T.; Gabathuler, E.; Gabathuler, K.; Garutti, E.; Garvey, J.; Gayler, J.; Gerhards, R.; Gerlich, C.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Goyon, C.; Grab, C.; Grassler, H.; Greenshaw, T.; Gregori, M.; Grindhammer, Guenter; Gwilliam, C.; Haidt, D.; Hajduk, L.; Haller, J.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Henshaw, O.; Herrera, G.; Herynek, I.; Heuer, R.-D.; Hildebrandt, M.; Hiller, K.H.; Hoting, P.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, H.; Kant, D.; Kapichine, M.; Karlsson, M.; Katzy, J.; Keller, N.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Koutouev, R.; Kropivnitskaya, A.; Kruger, K.; Kuckens, J.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebedev, A.; Leiner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; List, B.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lueders, H.; Luke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marks, J.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxeld, S.J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nagovizin, V.; Nankov, K.; Naroska, B.; Naumann, J.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Ozerov, D.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Poschl, R.; Portheault, B.; Povh, B.; Prideaux, P.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauvan, E.; Schatzel, S.; Scheins, J.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schneider, M.; Schoeffel, L.; Schoning, A.; Schroder, V.; Schultz-Coulon, H.-C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Sheviakov, I.; Shtarkov, L.N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Stella, B.; Stiewe, J.; Strauch, I.; Straumann, U.; Tchoulakov, V.; Thompson, Graham; Thompson, P.D.; Tomasz, F.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Uraev, A.; Urban, Marcel; Usik, A.; Utkin, D.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Van Remortel, N.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vest, A.; Vinokurova, S.; Volchinski, V.; Vujicic, B.; Wacker, K.; Wagner, J.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Werner, N.; Wessels, M.; Wessling, B.; Wigmore, C.; Winter, G.-G.; Wissing, Ch.; Woehrling, E.-E.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zimmermann, J.; Zohrabyan, H.; Zomer, F.

    2004-01-01

    Measurements are presented of inclusive charm and beauty cross sections in e^+p collisions at HERA for values of photon virtuality Q^2 > 150 GeV^2 and of inelasticity 0.1 < y < 0.7. The charm and beauty fractions are determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured by the H1 vertex detector. The data are divided into four regions in Q^2 and Bjorken x, and values for the structure functions F_2^{c\\bar{c}} and F_2^{b\\bar{b}} are obtained. The results are found to be compatible with the predictions of perturbative quantum chromodynamics.

  10. Demonstration of Hepatitis C Virus RNA with In Situ Hybridization Employing a Locked Nucleic Acid Probe in Humanized Liver of Infected Chimeric Mice and in Needle-Biopsied Human Liver

    Directory of Open Access Journals (Sweden)

    Kazuya Shiogama

    2013-01-01

    Full Text Available Background. In situ hybridization (ISH with high sensitivity has been requested to demonstrate hepatitis C virus (HCV RNA in formalin-fixed, paraffin-embedded (FFPE sections of the liver. Methods. ISH employing a locked-nucleic-acid- (LNA-modified oligonucleotide probe and biotin-free catalyzed signal amplification system (CSAII was applied to HCV-RNA detection in the liver tissue. Nested reverse-transcription polymerase chain reaction (RT-PCR was performed for HCV genotyping using total RNA extracted from FFPE sections. The target tissues included FFPE tissue sections of humanized livers in HCV-infected chimeric mice (HCV genotypes 1a, 1b, and 2a and noninfected and of needle-biopsied livers from HCV-infected patients. Results. HCV-RNA was demonstrated with the ISH technique in HCV-infected liver tissues from both chimeric mice and 9 (82% of 11 patients with HCV infection. The HCV signals were sensitive to RNase. Nested RT-PCR confirmed the genotype in 8 (73% of 11 livers (type 1b: 6 lesions and type 2a: 2 lesions. HCV-RNA was not identified in chronic hepatitis B lesions, fatty liver, autoimmune hepatitis, and hepatocellular carcinoma. Conclusion. ISH using the LNA-modified oligonucleotide probe and CSAII was applicable to detecting HCV-RNA in routinely prepared FFPE liver specimens.

  11. Simultaneous response of NmF2 and GPS-TEC to storm events at Ilorin

    Science.gov (United States)

    Joshua, B. W.; Adeniyi, J. O.; Oladipo, O. A.; Doherty, P. H.; Adimula, I. A.; Olawepo, A. O.; Adebiyi, S. J.

    2018-06-01

    A comparative study of both TEC and NmF2 variations during quiet and disturbed conditions has been investigated using simultaneous measurements from dual frequency Global Positioning System (GPS) receiver and a DPS-4 Digisonde co-located at Ilorin (Geog. Lat. 8.50°N, Long. 4.50°E, dip. - 7.9°). The results of the quiet time variations of the two parameters show some similarities as well as differences in their structures. The values of both parameters generally increase during the sunrise period attaining a peak around the noon and then decaying towards the night time. The onset time of the sunrise growth is observed to be earlier in TEC than in NmF2. The rate of decay of TEC was observed to be faster than that of the NmF2 in most cases. Also, the noon 'bite-outs', leading to the formation of pre-noon and post-noon peaks, are prominent in the NmF2 structure and was hardly noticed in TEC. Results of the variations of both TEC and NmF2 during the 5 April, 10 May and 3 August 2010 geomagnetic storm events showed a simultaneous deviations of both parameters from the quiet time behavior. The magnitude of the deviations is however most pronounced in NmF2 structure than in TEC. We also found that the enhancement observed in the two parameters during the storm events generally corresponds to decrease in hmF2.

  12. Assigning the Cerium Oxidation State for CH2CeF2 and OCeF2 Based on Multireference Wave Function Analysis.

    Science.gov (United States)

    Mooßen, Oliver; Dolg, Michael

    2016-06-09

    The geometric and electronic structure of the recently experimentally studied molecules ZCeF2 (Z = CH2, O) was investigated by density functional theory (DFT) and wave function-based ab initio methods. Special attention was paid to the Ce-Z metal-ligand bonding, especially to the nature of the interaction between the Ce 4f and the Z 2p orbitals and the possible multiconfigurational character arising from it, as well as to the assignment of an oxidation state of Ce reflecting the electronic structure. Complete active space self-consistent field (CASSCF) calculations were performed, followed by orbital rotations in the active orbital space. The methylene compound CH2CeF2 has an open-shell singlet ground state, which is characterized by a two-configurational wave function in the basis of the strongly mixed natural CASSCF orbitals. The system can also be described in a very compact way by the dominant Ce 4f(1) C 2p(1) configuration, if nearly pure Ce 4f and C 2p orbitals are used. In the basis of these localized orbitals, the molecule is almost monoconfigurational and should be best described as a Ce(III) system. The singlet ground state of the oxygen OCeF2 complex is of closed-shell character when a monoconfigurational wave function with very strongly mixed Ce 4f and O 2p CASSCF natural orbitals is used for the description. The transformation to orbitals localized on the cerium and oxygen atoms leads to a multiconfigurational wave function and reveals characteristics of a mixed valent Ce(IV)/Ce(III) compound. Additionally, the interactions of the localized active orbitals were analyzed by evaluating the expectation values of the charge fluctuation operator and the local spin operator. The Ce 4f and C 2p orbital interaction of the CH2CeF2 compound is weakly covalent and resembles the interaction of the H 1s orbitals in a stretched hydrogen dimer. In contrast, the interaction of the localized active orbitals for OCeF2 shows ionic character. Calculated vibrational Ce

  13. 26 CFR 1.280F-2T - Limitations on recovery deductions and the investment tax credit for certain passenger...

    Science.gov (United States)

    2010-04-01

    ... investment tax credit for certain passenger automobiles (temporary). 1.280F-2T Section 1.280F-2T Internal... TAXES Items Not Deductible § 1.280F-2T Limitations on recovery deductions and the investment tax credit for certain passenger automobiles (temporary). (a) Limitation on amount of investment tax credit—(1...

  14. Colloidal synthesis of BaF2 nanoparticles and their application as fillers in polymer nanocomposites

    Science.gov (United States)

    Sathyamurthy, Srivatsan; Tuncer, Enis; More, Karren L.; Gu, Baohua; Sauers, Isidor; Paranthaman, M. Parans

    2012-03-01

    Nanoparticles of pure and Eu-doped BaF2 have been prepared through sol-gel colloidal synthesis. In addition, BaF2-filled PMMA polymer nanocomposites were fabricated and dielectric properties were measured. The as-synthesized pure and Eu-doped BaF2 nanoparticles were analyzed by both X-ray diffraction and transmission electron microscopy and consisted of crystalline BaF2 particles with an average diameter of 13.6 nm with a standard deviation of about ±2.4 nm. The photoluminescence properties of the pure and Eu-doped (2%, 4% and 8%) nanoparticles showed characteristic emission of Eu3+ (5D0→7F J ( J=1-4) transitions). We also measured significantly enhanced dielectric breakdown strength of up to 30% for BaF2 nanocomposites over the unfilled PMMA polymer. This study thus offers some promise of sol-gel synthesis of nanocomposite dielectrics with great potential for use as electrical insulation materials in cryogenic high-voltage applications.

  15. Colloidal synthesis of BaF2 nanoparticles and their application as fillers in polymer nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Sathyamurthy, Srivatsan [ORNL; Tuncer, Enis [ORNL; More, Karren Leslie [ORNL; Gu, Baohua [ORNL; Sauers, Isidor [ORNL; Paranthaman, Mariappan Parans [ORNL

    2012-01-01

    Nanoparticles of pure and Eu-doped BaF2 have been prepared through sol-gel colloidal synthesis. In addition, BaF2 filled PMMA polymer nanocomposites were fabricated and dielectric properties were measured. The as-synthesized pure and Eu-doped BaF2 nanoparticles were analyzed by both X-ray diffraction and transmission electron microscopy and consisted of crystalline BaF2 particles with an average diameter of 13.6 nm with a standard deviation of about 2.4 nm. The photoluminescence properties of the pure and Eu-doped (2%, 4% and 8%) nanoparticles showed characteristic emission of Eu3+ (5D0 7FJ (J=1-4) transitions). We also measured significantly enhanced dielectric breakdown strength of up to 30% for BaF2 nanocomposites over the unfilled PMMA polymer. This study thus offers some promise of sol-gel synthesis of nanocomposite dielectrics with great potential for use as electrical insulation materials in cryogenic high voltage applications.

  16. Synthesis, characterization of CaF2 doped silicate glass-ceramics.

    Science.gov (United States)

    Riaz, Madeeha; Zia, Rehana; Mirza, Ambreen; Hussain, Tousif; Bashir, Farooq; Anjum, Safia

    2017-06-01

    This paper reports the fabrication and characterization of silicate glass-ceramics doped with (0-12mol%) CaF 2 . TGA-DSC analysis was carried out to determine the crystallization temperature and stability of glass measured by two glass parameters; Hruby parameter K H =(T x -T g )/(T L -T x ) and Weinberg parameter K W =(T c -T g )/T L . It was found that with CaF 2 doping improved sinterability at low temperature and provided stability to the glass. The XRD pattern exhibits a single phase of combeite and doping of CaF 2 cause increase in crystallite size. Microstructure of samples was also improved with CaF 2 addition, pores were significantly reduced. After 15days immersion in simulated body fluid all samples developed apatite layer onto its surface. Hence, the addition of CaF 2 provided bioactive glass-ceramic material having a low processing temperature. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Size Controlled CaF2 Nanocubes and Their Dosimetric Properties Using Photoluminescence Technique

    Directory of Open Access Journals (Sweden)

    Najlaa D. Alharbi

    2015-01-01

    Full Text Available A new synthetic chemical coprecipitation route for the preparation of well-crystallized size controlled nano- and microcrystalline cubes of CaF2 is reported. Crystalline cubes in the range of 2 μm–20 nm could be synthesized and their sizes were controlled by varying the solvent : cosolvent ratio. The as-synthesized CaF2 nanocubes were characterized by different techniques. Photoluminescence (PL emission spectrum of CaF2 nanocrystalline powder showed strong emission band at 415 nm. Moreover, the effect of Eu as a dopant on the emission spectrum of CaF2 was investigated. This dopant was found to get incorporated in its Eu2+ and Eu3+ forms. The as-produced nanocubes were exposed to UV irradiation and the corresponding PL emission was studied. Excellent results are obtained, where CaF2:Eu nanocubes were found to be highly sensitive and might be suitable for esteeming the doses of UV irradiation using the PL technique.

  18. Afterglow properties of CaF2:Tm nanoparticles and its potential application in photodynamic therapy

    International Nuclear Information System (INIS)

    Zahedifar, M.; Sadeghi, E.; Shanei, M.M.; Sazgarnia, A.; Mehrabi, M.

    2016-01-01

    CaF 2 :Tm nanoparticles (NPs) were synthesized by the hydrothermal method. Intense afterglow emission with long life time was found for the produced NPs, so its applicability in photodynamic therapy was investigated. Since the wavelength of the afterglow emission of the NPs fairly matches with the absorption band of the PpIX sensitizer, especially in the red region, the Cystein mediator was used to bond NPs with the PpIX sensitizer. The CaF 2 :Tm NPs conjugated with PpIX was exposed to X-ray and by using the Antracene as detector, the production of the singlet oxygen was verified. Therefore, the produced NPs are recommended as a source of energy that improves photodynamic therapy beyond its current limitations. - Highlights: • Intense afterglow emission found for the synthesized CaF 2 :Tm nanoparticles. • CaF 2 :Tm emission band fairly matched with PpIX sensitizer's absorption band. • CaF 2 :Tm conjugated with the sensitized is a good candidate for photodynamic therapy. • The application of nanoparticles in producing singlet oxygen was verified.

  19. Variation of saturation effect in the ionospheric F2 critical frequency at low latitude

    Science.gov (United States)

    Ikubanni, S. O.; Adeniyi, J. O.

    2013-08-01

    Saturation in the dependence of foF2 on solar flux is a phenomenon more pronounced in the equatorial ionization anomaly region. The phenomenon was observed in the relationship between the F2 critical frequency (foF2) and any solar indices. Using a two-segmented regression fit on data from an African low latitude station (Geographical Latitude 12.4°N; Geomagnetic latitude 3.5°N), saturation features from the dependence of foF2 on solar radio flux (F10.7) was studied. Diurnal and seasonal variation were studied for the first time in this low latitude region of the African sector. Significant variations were observed, especially in the solstices. It was observed that saturation effect is closely related to the hourly F2 critical frequency and these results were compared with those from Asian, Australian and the American sectors. The diurnal and seasonal variations find their explanations in the photo-ionization process, the fountain effect, and the pre-reversal enhancement while the seasonal variation was attributed to both the ion drift and thermospheric circulation. Future work with larger volume of data is expected to validate the observations from this study.

  20. Sexual dimorphism in hybrids rats.

    Science.gov (United States)

    Garcia-Falgueras, Alicia; Pinos, Helena; Fernández, Rosa; Collado, Paloma; Pasaro, Eduardo; Segovia, Santiago; Guillamon, Antonio

    2006-12-06

    Laboratory rat strains descend from Wistar rats as a consequence of artificial selection. Previously we reported that the medial posterior division of the bed nucleus of the stria terminalis (BSTMP) was sexually dimorphic in Wistar and Long-Evans strains while the medial anterior division (BSTMA) and the locus coeruleus (LC) only showed sex differences in the ancestor Wistar strain. The lateral posterior division (BSTLP) was isomorphic in both strains. The present work studies the number of neurons in the BSTMP, BSTMA, BSTLP and LC of male and female Wistar and Long-Evans rats (F(0)) and their hybrid F(1) and F(2) generations. The BSTMP is sexually dimorphic in the F(0), F(1) and F(2) generations while sex differences in the LC are only seen in F(0) Wistar rats but not in the F(0) Long-Evans or the F(1) and F(2) hybrid generations. Sex differences in the BSTMA are seen in F(0) Wistar but not in F(0) Long-Evans rats and completely disappear in the F(2) generations. The number of neurons in the LC of both males and females decreased in heterozygotic individuals (F(1)) but increased in homozygotic (F(2)). However, the number of neurons in the BSTMP changes significantly over the generations, although the ratio of neurons (female/male) is stable and unaffected in homo- or heterozygosis. Thus, the mechanism that regulates the neuronal female/male ratio would be different from the one that controls the number of neurons. The facts that sex differences in the BSTMP are not affected by homo- or heterozygosis and that they are seen in several mammalian orders suggest the existence of a "fixed" type of brain sex differences in the Mammalia Class.

  1. Durability of ITO-MgF2 Films for Space-Inflatable Polymer Structures

    Science.gov (United States)

    Kerslake, Thomas W.; Waters, Deborah L.; Schieman, David A.; Hambourger, Paul D.

    2003-01-01

    This paper presents results from ITO-MgF2 film durability evaluations that included tape peel, fold, thermal cycle, and AO exposure testing. Polymer coupon preparation is described as well as ITO-MgF2 film deposition equipment, procedures and film characterization. Durability testing methods are also described. The pre- and post-test condition of the films is assessed visually, microscopically, and electrically. Results show that at 500 ITO - 9 vol% MgF2 film is suitable to protect polymer surfaces, such as those used in space-inflatable structures of the PowerSphere microsatellite concept, during a 1-year Earth orbiting mission. Future plans for ground-based and orbital testing of this film are also discussed.

  2. ESR of Ag2+ ions in S2F2 crystal

    International Nuclear Information System (INIS)

    Zaripov, M.M.; Ulanov, V.A.; Falin, M.L.

    1989-01-01

    Experimental data on investigation of bivalent silver ions in S 2 F 2 crystals are presented. Due to the investigation of the grown crystals it is determined that centres of univalent silver ore formed in SrF 2 during crystal growth. X-ray irradiation at room temperature results in the transition of these centres in bivalent staes. Investigation of temperature dependence of ESR spectra type has allowed to make the conclusion about the presence of Jahn-Teller dynamic effect. Analysis of experimental data allows to develop a model of the investigated paramagnetic complex in S 2 F 2 crystal where Ag 2* ion has coordination polyhedron in the form of eight F - ion cube distorted by C 3 3 axis

  3. Measurement of the electron structure function F2e at LEP energies

    Directory of Open Access Journals (Sweden)

    J. Abdallah

    2014-10-01

    Full Text Available The hadronic part of the electron structure function F2e has been measured for the first time, using e+e− data collected by the DELPHI experiment at LEP, at centre-of-mass energies of s=91.2–209.5 GeV. The data analysis is simpler than that of the measurement of the photon structure function. The electron structure function F2e data are compared to predictions of phenomenological models based on the photon structure function. It is shown that the contribution of large target photon virtualities is significant. The data presented can serve as a cross-check of the photon structure function F2γ analyses and help in refining existing parameterisations.

  4. Identification of θ(f2(1720)) as a tensor glueball

    International Nuclear Information System (INIS)

    Liu, K.F.

    1988-01-01

    The energy-momentum tensor matrix element for the tensor glueball is obtained from the tensor dominance model. Branching ratio of θ(f 2 (1720)) in J/ψ radiative decay is thus calculated which is in accord with the observed experimental branching ratio. The decay modes of θ(f 2 (1720)) and results from J/ψ→ γK bar K,ωK bar K, and φK bar K are taken as good indicators for flavor independence of the tensor meson Θ. Suppression of θ(f 2 (1720)) in γγ reaction and K - p → ΛK o s K o s are considered as evidence for the fact that there are no quarks in θ. From the combined theoretical and experimental studies, the authors conclude that θ is by far the best tensor glueball candidate

  5. Solar Cycle variations of ƒoF2 from IGY to 1990

    Directory of Open Access Journals (Sweden)

    M. K. Goel

    Full Text Available Noontime monthly median values of F2-layer critical frequency foF2 (m for some ionospheric stations representing low- and mid-latitudes are examined for their dependence on solar activity for the years 1957 (IGY to 1990. This is the period for which ionospheric data in digital form is available in two CD-ROMs at the World Data Center, Boulder. It is observed that at mid-latitudes, foF2 (m shows nearly a linear relationship with R12 (the 12-month running average of the Zurich sunspot number, though this relation is nonlinear for low-latitudes. These results indicate some departures from the existing information often used in theoretical and applied areas of space research.Key words. Ionosphere (equatorial ionosphere; mid-latitude ionosphere; modelling and forecasting

  6. Interface reaction and wetting in the CaF2/Me systems

    International Nuclear Information System (INIS)

    Barzilai, S.; Aizenshtein, M.; Lomberg, M.; Froumin, N.; Frage, N.

    2008-01-01

    Wetting experiments using the sessile drop method were performed in the CaF 2 -Me systems (Me = Cu, Ge, Al, In and Ga). Liquid Cu, Ge, In and Ga, do not wet the CaF 2 substrate and contact angles are significantly higher than 90 deg. No condensed products were found at the metal/ceramic interface. In the CaF 2 /Al system, evidence of an interface interaction was detected and the contact angle is about 92 deg. It was established that the spreading behavior and the values of the apparent contact angle depend on the rate of evaporation of the molten metals, the rate of sublimation of the substrate and on the value of the work of adhesion at the interface. The experimental observations are well accounted for by a thermodynamic analysis of the ternary Ca-Me-F systems

  7. Variability study of foF2 for an equatorial station

    International Nuclear Information System (INIS)

    Adeniyi, J.O.; Radicella, S.M.; Adimula, I.A.

    1994-08-01

    The deviation of hourly values of foF 2 from the monthly median values was used to study the variability of foF 2 . The study was done for the period of high and low solar activity. Generally the range of variation of the deviation is not dependent on solar activity. There is a tendency for positive deviation to occur on magnetically disturbed days and for negative deviation to occur on quiet days. The magnitude of the deviation does not depend on whether the day is disturbed or quiet. The correlation between Ap index and deviation of foF 2 from the median value is generally poor. THe range of deviation at night is usually higher than that of the daytime for the period of high solar activity. Some seasonal effect were also observed on the deviation. (author). 4 refs, 5 figs, 3 tabs

  8. Fast neutron responses of CaF2:Tm Teflon TLD discs of different thicknesses

    International Nuclear Information System (INIS)

    Pradhan, A.S.; Hoffmann, W.

    1986-01-01

    The fact that in CaF 2 :Tm (TLD-300) the ratio of the heights of thermoluminescence (TL) glow peaks at 240 0 C and 150 0 C is greater for irradiations by high LET radiations than by gamma rays has been found useful for the simultaneous and separate measurement of fast neutron and gamma ray absorbed doses. A recent study has indicated that the mixed field dosimetric characteristics of CaF 2 :Tm could be significantly improved by using thin TLDs. In the present study, CaF 2 :Tm Teflon TLD discs of thickness as low as 0.05 mm were evaluated. The thin discs could be read out by using normal planchette heating if a 400 0 C heat treatment is given to the discs prior to irradiation and TL readout. Influence of encapsulation of thin dosemeters was studied and their utility in situations such as interface dosimetry is discussed. (author)

  9. 2.4 μm diode-pumped Dy2+:CaF2 laser

    Science.gov (United States)

    Švejkar, Richard; Papashvili, Alexander G.; Šulc, Jan; Němec, Michal; Jelínková, Helena; Doroshenko, Maxim E.; Batygov, Sergei H.; Osiko, Vyacheslav V.

    2018-01-01

    In this work, a cryogenic cooled, longitudinal diode-pumped Dy2+ :CaF2 laser was investigated for the first time. The temperature dependence of the spectroscopy and the laser properties of Dy2+ :CaF2 are presented. The tested Dy2+ :CaF2 crystal was a longitudinal pump in a near-IR region (926 nm) by laser diode radiation. The maximal mean output power and slope efficiency at 78 K during the pulse regime of the laser were 57.5 mW and 7%, respectively. Furthermore, the CW regime was successfully tested and a maximum output power of 0.37 W was obtained for the absorbed pumping power 5.7 W. The emission laser wavelength was 2367 nm.

  10. Microwave, High-Resolution Infrared, and Quantum Chemical Investigations of CHBrF2

    DEFF Research Database (Denmark)

    Cazzoli, Gabriele; Cludi, Lino; Puzzarini, Cristina

    2011-01-01

    terms as well as the hyperfine parameters (quadrupole-coupling and spin-rotation interaction constants) of the bromine nucleus. The determination of the latter was made possible by recording of spectra at sub-Doppler resolution, achieved by means of the Lamb-dip technique, and supporting the spectra......A combined microwave, infrared, and computational investigation of CHBrF2 is reported. For the vibrational ground state, measurements in the millimeter- and sub-millimeter-wave regions for (CHBrF2)-Br-79 and (CHBrF2)-Br-81 provided rotational and centrifugal-distortion constants up to the sextic...... parameters of the v(4) = 1 state were found to be close to those of the vibrational ground state, indicating that the v(4) band is essentially unaffected by perturbations....

  11. Diode-pumped femtosecond mode-locked Nd, Y-codoped CaF2 laser

    International Nuclear Information System (INIS)

    Zhu, Jiangfeng; Zhang, Lijuan; Gao, Ziye; Wang, Junli; Wang, Zhaohua; Wei, Zhiyi; Su, Liangbi; Zheng, Lihe; Wang, Jingya; Xu, Jun

    2015-01-01

    A passively mode-locked femtosecond laser based on an Nd, Y-codoped CaF 2 disordered crystal was demonstrated. The Y 3+ -codoping in Nd : CaF 2 markedly suppressed the quenching effect and improved the fluorescence quantum efficiency and emission spectra. With a fiber-coupled laser diode as the pump source, the continuous wave tuning range covering from 1042 to 1076 nm was realized, while the mode-locked operation generated 264 fs pulses with an average output power of 180 mW at a repetition rate of 85 MHz. The experimental results show that the Nd, Y-codoped CaF 2 disordered crystal has potential in a new generation diode-pumped high repetition rate chirped pulse amplifier. (letter)

  12. Ultraviolet radiation monitoring in makkah city, Saudi Arabia, using thermoluminescence material CaF2:Tm

    International Nuclear Information System (INIS)

    Al-Ghorabie, F.H.; Natto, S.S.; AL-Lehyani, S.A.

    2005-01-01

    The aim of the present study is to explore the possibility of using Ca F2:Tm thermoluminescence material for measuring and monitoring of solar UV R in Makkah City, Saudi Arabia. Several laboratory experiments, prior to the field measurements, were performed included study of the effects of ultraviolet wavelengths on the response of the phosphor, study of the effect of increasing ultraviolet radiation dose on the intensity of thermoluminescence and study the effect of time factor on the thermoluminescence fading of Ca F 2 :Tm. The phosphor was then exposed directly for one hour to sunlight radiation on a daily basis for 90 days in an open field inside Umm Al-Qura university campus. The field measurements were performed during the months of June, July and August 2003 at 1:00 p.m. The laboratory and field results of this study showed that Ca F 2 :Tm can be used as a suitable dosimeter for solar UV R

  13. Software data acquisition system for the ''Chateau de Cristal'' multicounter 74 BaF2

    International Nuclear Information System (INIS)

    Adzama, G.

    1985-01-01

    The ''Chateau de Cristal'' is a 74 BaF2 detector assembly. Other detectors such as Ge (up to 12) and particle detectors can be added to this multidetector. The data acquisition system hardware and software are implemented in 3 VME crates. The operating system is handled by 68000 Motorola microprocessors. This work is dedicated to the initialization and control tasks of the multidetector. Handling of high voltage power supply for the 74 BaF2 detectors via a RS 232 C serial port, CAMAC initialization for the ADC 4300 Lecroy and DFC modules, data exchange between the 3 VME crates and automatic energy calibration for the BaF2 detectors. All the software is written in 68000 Motorola assembly language [fr

  14. The synthesis of PbF2 nanorods in a microemulsion system

    International Nuclear Information System (INIS)

    Xu Ke; Mao Changjie; Geng Jun; Zhu Junjie

    2007-01-01

    Single-crystalline PbF 2 nanorods with a diameter of 100-500 nm and length of 1-10 μm have been successfully synthesized by a simple sonochemical route in a microemulsion system at room temperature. The morphologies and structures of the nanorods were characterized by x-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy. The experimental results showed that polyethylene glycol 6000 played an important role in the formation of PbF 2 nanorods. Room-temperature photoluminescence measurements indicated that the as-prepared PbF 2 nanorods had strong green emission, which could have potential applications in optoelectronic devices

  15. The proapoptotic influenza A virus protein PB1-F2 forms a nonselective ion channel.

    Directory of Open Access Journals (Sweden)

    Michael Henkel

    2010-06-01

    Full Text Available PB1-F2 is a proapoptotic influenza A virus protein of approximately 90 amino acids in length that is located in the nucleus, cytosol and in the mitochondria membrane of infected cells. Previous studies indicated that the molecule destabilizes planar lipid bilayers and has a strong inherent tendency for multimerization. This may be correlate with its capacity to induce mitochondrial membrane depolarization.Here, we investigated whether PB1-F2 is able to form ion channels within planar lipid bilayers and microsomes. For that purpose, a set of biologically active synthetic versions of PB1-F2 (sPB1-F2 derived from the IAV isolates A/Puerto Rico/8/34(H1N1 (IAV(PR8, from A/Brevig Mission/1/1918(H1N1 (IAV(SF2 or the H5N1 consensus sequence (IAV(BF2 were used. Electrical and fluorimetric measurements show that all three peptides generate in planar lipid bilayers or in liposomes, respectively, a barely selective conductance that is associated with stochastic channel type fluctuations between a closed state and at least two defined open states. Unitary channel fluctuations were also generated when a truncated protein comprising only the 37 c-terminal amino acids of sPB1-F2 was reconstituted in bilayers. Experiments were complemented by extensive molecular dynamics simulations of the truncated fragment in a lipid bilayer. The results indicate that the c-terminal region exhibits a slightly bent helical fold, which is stable and remains embedded in the bilayer for over 180 ns.The data support the idea that PB1-F2 is able to form protein channel pores with no appreciable selectivity in membranes and that the c-terminus is important for this function. This information could be important for drug development.

  16. Effect of aging and radiation in mice of different genotypes

    International Nuclear Information System (INIS)

    Storer, J.B.

    1976-01-01

    Data are presented on the life span of nine inbred strains and five hybrid strains of mice based on 400 mice of each sex for inbred and 200 mice of each sex for hybrid. Some of these mice were exposed when 120 days old to 250 R or 450 R of x radiation delivered at a dose rate of 60 R/min. Data on strain, sample size, and mean survival times are presented in tables

  17. [18F]-2-FDG as a tool for studying hexokinase kinetics

    International Nuclear Information System (INIS)

    Mertens, J.; Gysemans, M.

    1990-01-01

    In the basic research related to the development of radiolabelled glucose analogues or to sugar metabolism, the measurement of hexokinase kinetics is very important. The article of S. J. Gatley et al about the quality control of [ 18 F]-2-FDG preparations using the hexokinase reaction in vitro was the basic idea of the method proposed in this paper dealing with the direct measurement of hexokinase kinetics by the measurement of the activity related to [ 18 F]-2-FDG-6-phosphate. Experimental results indicate that the method is appropriate for hexokinase studies

  18. Measurement of the proton structure function F2 in ep scattering at HERA

    International Nuclear Information System (INIS)

    Derrick, M.; Krakauer, D.; Magill, S.

    1993-08-01

    This paper presents our first measurement of the F 2 structure function in neutral-current, deep inelastic scattering using the ZEUS detector at HERA, the ep colliding beam facility at DESY. The data correspond to an integrated luminosity of 24.7 nb -1 . Results are presented for data in a range of Q 2 from 10 GeV 2 to 4700 GeV 2 and Bjorken x down to 3.0x10 -4 . The F 2 structure function increases rapidly as x decreases. (orig.)

  19. Transmission of electric fields and photoelectron fluxes between conjugate ionospheric F2-regions

    International Nuclear Information System (INIS)

    Petelski, E.F.

    1975-01-01

    The dynamic behaviour of the ionospheric F2-layer requires considerable vertical transport of ionization. Possible causes of such transport are ambipolar diffusion, neutral air winds and electric fields. Here mid-latitude electric fields are investigated. Real height variations of the F2-layer indicate that the phases and amplitudes of these fields are similar at well conjugate points and that the field strengths can become unexpectedly high. It is further shown that photoelectrons can migrate between the two hemispheres along the geomagnetic field lines. (orig.) [de

  20. Fluorine dynamics in BaF2 superionic conductors investigated by NMR

    OpenAIRE

    Gumann, Patryk

    2008-01-01

    In this work the dynamics of fluorine in solid-state electrolytes having BaF2-structure was investigated using three different NMR-methods: field cycling relaxometry, lineshape analysis, and static field gradient NMR. For this purpose a pure BaF2 crystal, as well as crystals doped with trivalent impurities (LaF3), were studied as a function of temperature. The main goal of this investigation was to utilize the structure information provided by neutron scattering and MAS NMR data in order to s...

  1. The f2(1565) in pbar-p -> (omega-omega)pizero interactions at rest

    CERN Document Server

    Baker, C.A.; Batty, C.J.; Braune, K.; Bugg, D.V.; Cramer, O.; Crede, V.; Djaoshvili, N.; Dunnweber, W.; Faessler, M.A.; Hessey, N.P.; Hidas, P.; Hodd, C.; Jamnik, D.; Kilinowsky, H.; Kisiel, J.; Klempt, E.; Kolo, C.; Montanet, L.; Pick, B.; Roethel, W.; Sarantsev, A.; Scott, I.; Strassburger, C.; Thoma, U.; Volcker, C.; Wallis, S.; Walther, D.; Wittmack, K.; Zou, B.S.

    2011-01-01

    Data are presented on the reaction pbar-p -> omega-omega-pizero at rest from the Crystal Barrel detector. These data identify a strong signal due to f2(1565) -> omega-omega. The relative production from initial pbar-p states 3P2, 3P1 and 1S0 is well determined from omega-omega decay angular correlations; P-state annihilation dominates strongly. A combined fit is made with data on pbar-p -> 3pizero at rest, where f2(1565) -> pizero-pizero is observed.

  2. Development of F2 two-step fluorination process for non-aqueous reprocessing

    International Nuclear Information System (INIS)

    1976-02-01

    To establish the F 2 two-step fluorination for stable and high recoveries of plutonium, the fluorination process has been studied with the simulated fuel to a FBR containing UO 2 - PuO 2 and non-radioactive fission products in the 2''phi fluid-bed. The process principle was demonstrated and the effect of FPs on fluorination of U and Pu and the possibility of reducing the Pu loss could be clarified. The feasibility of separating PuF 6 from UF 6 onto UO 2 F 2 by adsorption, was also indicated. (auth.)

  3. Annual and semiannual variations in the ionospheric F2-layer: II. Physical discussion

    Directory of Open Access Journals (Sweden)

    H. Rishbeth

    2000-08-01

    Full Text Available The companion paper by Zou et al. shows that the annual and semiannual variations in the peak F2-layer electron density (NmF2 at midlatitudes can be reproduced by a coupled thermosphere-ionosphere computational model (CTIP, without recourse to external influences such as the solar wind, or waves and tides originating in the lower atmosphere. The present work discusses the physics in greater detail. It shows that noon NmF2 is closely related to the ambient atomic/molecular concentration ratio, and suggests that the variations of NmF2 with geographic and magnetic longitude are largely due to the geometry of the auroral ovals. It also concludes that electric fields play no important part in the dynamics of the midlatitude thermosphere. Our modelling leads to the following picture of the global three-dimensional thermospheric circulation which, as envisaged by Duncan, is the key to explaining the F2-layer variations. At solstice, the almost continuous solar input at high summer latitudes drives a prevailing summer-to-winter wind, with upwelling at low latitudes and throughout most of the summer hemisphere, and a zone of downwelling in the winter hemisphere, just equatorward of the auroral oval. These motions affect thermospheric composition more than do the alternating day/night (up-and-down motions at equinox. As a result, the thermosphere as a whole is more molecular at solstice than at equinox. Taken in conjunction with the well-known relation of F2-layer electron density to the atomic/molecular ratio in the neutral air, this explains the F2-layer semiannual effect in NmF2 that prevails at low and middle latitudes. At higher midlatitudes, the seasonal behaviour depends on the geographic latitude of the winter downwelling zone, though the effect of the composition changes is modified by the large solar zenith angle at midwinter. The zenith angle effect is especially important in longitudes far from the magnetic poles. Here, the downwelling occurs

  4. Annual and semiannual variations in the ionospheric F2-layer: II. Physical discussion

    Directory of Open Access Journals (Sweden)

    H. Rishbeth

    Full Text Available The companion paper by Zou et al. shows that the annual and semiannual variations in the peak F2-layer electron density (NmF2 at midlatitudes can be reproduced by a coupled thermosphere-ionosphere computational model (CTIP, without recourse to external influences such as the solar wind, or waves and tides originating in the lower atmosphere. The present work discusses the physics in greater detail. It shows that noon NmF2 is closely related to the ambient atomic/molecular concentration ratio, and suggests that the variations of NmF2 with geographic and magnetic longitude are largely due to the geometry of the auroral ovals. It also concludes that electric fields play no important part in the dynamics of the midlatitude thermosphere. Our modelling leads to the following picture of the global three-dimensional thermospheric circulation which, as envisaged by Duncan, is the key to explaining the F2-layer variations. At solstice, the almost continuous solar input at high summer latitudes drives a prevailing summer-to-winter wind, with upwelling at low latitudes and throughout most of the summer hemisphere, and a zone of downwelling in the winter hemisphere, just equatorward of the auroral oval. These motions affect thermospheric composition more than do the alternating day/night (up-and-down motions at equinox. As a result, the thermosphere as a whole is more molecular at solstice than at equinox. Taken in conjunction with the well-known relation of F2-layer electron density to the atomic/molecular ratio in the neutral air, this explains the F2-layer semiannual effect in NmF2 that prevails at low and middle latitudes. At higher midlatitudes, the seasonal behaviour depends on the geographic latitude of the winter downwelling zone, though the effect of the composition changes is modified by the large solar zenith angle at midwinter. The zenith angle effect is especially important in longitudes far from the magnetic

  5. Membrane ion transport in erythrocytes of salt hypertensive Dahl rats and their F2 hybrids: the importance of cholesterol

    Czech Academy of Sciences Publication Activity Database

    Vokurková, Martina; Dobešová, Zdenka; Kuneš, Jaroslav; Zicha, Josef

    2003-01-01

    Roč. 26, č. 5 (2003), s. 397-404 ISSN 0916-9636 R&D Projects: GA ČR GA305/00/1638; GA MŠk LN00A069 Institutional research plan: CEZ:AV0Z5011922 Keywords : ion transport * salt hypertension * plasma lipids Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.013, year: 2003

  6. Wetting induced by near-surface Ti-enrichment in the CaF2/In-Ti and CaF2/Cu-Ti systems

    International Nuclear Information System (INIS)

    Froumin, N.; Barzilai, S.; Aizenshtein, M.; Lomberg, M.; Frage, N.

    2008-01-01

    This paper is concerned with the wetting of CaF 2 by liquid Cu and In and with the effect of Ti additions to the melt. According to thermodynamic analysis and to the experimental observations, the significantly decreased contact angle following the addition of Ti to the molten metals is not due to the formation of interfacial fluoride phases, in contrast to previously reported results. Ab initio density functional calculations indicate that preferential Ti adsorption takes place at the near CaF 2 surface. It is suggested that the presence of a Ti-enriched liquid, adjacent to the substrate, gives rise, by means of heterogeneous nucleation, to the formation of a thin intermetallic compound layer that stands behind the experimentally observed enhanced wetting. The suggested wetting mechanism is supported by the notable correlation that has been observed between the temperature dependence of the contact angle and the temperature domains, associated with the presence of intermetallic compounds in both Me-Ti (Me = Cu, In) binary systems

  7. Analysis of the Rare Decay $B_s \\rightarrow f_2' \\mu^+ \\mu^-$ with $f_2' \\rightarrow K^+ K^-$ Final State

    CERN Document Server

    Berninghoff, Daniel Alexander

    2014-01-01

    This report describes the project that I worked on during my time as a summer student at CERN in summer 2014: A search for the rare decay $B_s \\rightarrow f_2' \\mu^+ \\mu^-$ at the LHCb experiment has been performed using data corresponding to an integrated luminosity $\\mathcal{L} = 3.0 \\text{ fb}^{-1}$. In the Standard Model (SM), this decay is highly suppressed as it proceeds via an electroweak penguin transition. New Physics (NP) effects can enter the loop and influence observables like the branching ratio $\\mathcal{B}$. A theoretical prediction of the branching ratio in the SM is given by $\\mathcal{B}_\\text{th}(B_s \\rightarrow f_2' \\mu^+ \\mu^-) = \\left( 1.8\\,^{+1.1}_{-0.7} \\right) \\cdot 10^{-7}$. We found $N_\\text{obs} = 17.2 \\pm 2.9$ signal candidates using a two dimensional mass fit which is in the same order of magnitude as the theoretical prediction $N_\\text{pred} = 15_{-7}^{+10}$. Though, further systematic effects in the analysis still have to be investigated before converting this into a reliable va...

  8. Estimation of ultraviolet radiation dose using CaF2:Tb phosphor

    International Nuclear Information System (INIS)

    Fukuda, Y.; Ohtaki, H.; Owaki, S.

    1996-01-01

    To observe and estimate the dose of ultraviolet (UV) radiation in sunlight, the available thermoluminescence (TL) materials were studied. Several kinds of lanthanide elements were doped in pure CaF 2 powdered crystal and the properties of the Tl for UV were observed. The TL intensity from CaF 2 :Tb was the highest among the samples doped with various lanthanide elements, and form the TL emission spectra (380-540 nm) the TL is estimated to be due to inner transition of Tb 3+ . The peak wavelength of the TL excitation light was located approximately at 235 nm and light of a longer wavelength than 320 nm was unable to excite the TL. The ultraviolet response of CaF 2 :Tb depended on its sintering temperature. Even without γ ray pre-irradiation the CaF 2 :Tb sample with 1 h exposure to sunlight has enough sensitivity to estimate the change of UV. Seasonal change of UV intensity in sunlight was measured with this TLD during four months in 1993. The results agreed with that of other institutes in Japan. (author)

  9. Electron density variations in the F2 layer maximum during solar activity cycle

    International Nuclear Information System (INIS)

    Besprozvannaya, A.S.; Kozina, P.E.; AN Kazakhskoj SSR, Alma-Ata. Sektor Ionosfery)

    1988-01-01

    R value, characterizing for F2 relation of hourly median values in solar activity minimum and maximum, is calculated by average monthly values of F2 layer critical frequencies for June, October and December 1958 and 1964. R latitudinal-temporal distributions are plotted for different seasons according to the data from the north hemisphere west and east stations, placed within the Φ'=35-70deg latitudes interval. The following peculiarities of F2 lyer ionization relation with solar activity are pointed out. There are day-time hours, they are - winter one characterized by the gain rate increase with the widths increase, and summer one, realizing the opposite regularity. In night-time hours R value is characterized by the abnormally low values (∼ 1.2) at the latitudes to the south of the ionospheric through and to the pole from it. For all three seasons during 24 hours the periods with ionization gain maximal rate, which occur at nights in summer time and in the hours after the sunset - in winter and equinoctial months, are observed. The quantitative explanation of the peculiarities detected concerning the to-day concepts on F2 layer formation mechanisms is given

  10. Study of VUV emission and γ-ray responses of Nd:BaF2 scintillaotor

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Kawaguchi, Noriaki; Yokota, Yuui; Ishidu, Sumito; Fukuda, Kentaro; Yoshikawa, Akira; Pejchal, Jan; Nikl, Martin; Babin, Vladimir; Sekiya, Hiroyuki; Kamada, Kei

    2010-01-01

    Nd 3+ 1%, 5% and 10% doped BaF 2 single crystals were grown by the micro-pulling down method. Photoluminescence properties, including excitation and emission spectra and luminescence decay were measured under synchrotron radiation excitation at the Superlumi station in HASYLAB at DESY (Hamburg, Germany). The Nd 3+ related 5d-4f emission lines peaking around 180 nm, 230 nm, and 260 nm, identified as the 5d- 4 I j , 5d- 4 F j , and 5d- 2 G j transitions, were observed under 140-168 nm excitation. In photoluminescence decay under the 160 nm excitation, the dominant component decay time is about 12, 2.5 and 1.2 ns for Nd 3+ 1%, 5% and 10% concentration, respectively. The decay time shortening is explained by the concentration quenching effect. Transmittance of Nd1% sample is about 80% for wavelengths above 185 nm. Finally, gamma-ray responses, non-proportionality and energy resolution of Nd1% sample were compared with the undoped BaF 2 scintillator. The light yield of the Nd1%:BaF 2 is about 93% of that of undoped BaF 2 .

  11. 26 CFR 1.904(f)-2T - Recapture of overall foreign losses (temporary).

    Science.gov (United States)

    2010-04-01

    ... $500 balance in the general category overall foreign loss account or $300 foreign source income in the... in the general category is recharacterized as U.S. source income. The balance in Y's general category..., see § 1.904(f)-2(a) and (b). (c) Section 904(f)(1) recapture—(1) In general. In a year in which a...

  12. A BaF2-BGO detector for high-energy gamma rays

    International Nuclear Information System (INIS)

    Bargholtz, C.; Ritzen, B.; Tegner, P.E.

    1989-01-01

    A scintillation detector has been developed for gamma rays with energy between a few hundred keV and approximately 100 MeV. The detector comprises a BaF 2 and a BGO crystal giving it good timing properties and a reasonably good energy resolution in combination with compact size. (orig.)

  13. A status report of the QCDSF N{sub f}=2+1 project

    Energy Technology Data Exchange (ETDEWEB)

    Goeckeler, Meinulf [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Horsley, Roger [Edinburgh Univ. (United Kingdom). School of Physics; Nakamura, Yoshifumi [DESY, Zeuthen (DE). John von Neumann Institute NIC] (and others)

    2007-12-20

    We report about on-going simulations of N{sub f}=2+1 lattice QCD. We use a tadpole improved Symanzik gauge action and stout link smeared Wilson fermions with a clover term. We employ the Hasenbusch trick for the degenerate u- and d-quarks, and the RHMC algorithm for the simulation of the strange quark. (orig.)

  14. Mineralization of CCl4 and CCl2F2 on solid surfaces

    International Nuclear Information System (INIS)

    Gaeb, S.; Schmitzer, J.; Turner, W.V.; Korte, F.; Technische Univ. Muenchen, Freising

    1980-01-01

    The mineralization of 14 CCl 4 and 14 CCl 2 F 2 in the dark is shown to be greatly dependent on the nature of the solid surfaces to which they are exposed, alumina being more effective than silica gel and a number of natural sands. Activation of the solids by drying or mechanically by tumbling leads to increased mineralization rates. (orig.)

  15. Vibrational excitation resulting from electron capture in LUMO of F2 ...

    Indian Academy of Sciences (India)

    of F2 and HCl – A treatment using the time-dependent wave ... using Fourier grid Hamiltonian method applied to potential energy (PE) curve of the neutral target. The result- ..... reason for splitting of the wave packet is unknown to us.

  16. F2 layer characteristics and electrojet strength over an equatorial station

    Science.gov (United States)

    Adebesin, B. O.; Adeniyi, J. O.; Adimula, I. A.; Reinisch, B. W.; Yumoto, K.

    2013-09-01

    The data presented in this work describes the diurnal and seasonal variation in hmF2, NmF2, and the electrojet current strength over an African equatorial station during a period of low solar activity. The F2 region horizontal magnetic element H revealed that the Solar quiet Sq(H) daily variation rises from early morning period to maximum around local noon and falls to lower values towards evening. The F2 ionospheric current responsible for the magnetic field variations is inferred to build up at the early morning hours, attaining maximum strength around 1200 LT. The Sq variation across the entire months was higher during the daytime than nighttime. This is ascribed to the variability of the ionospheric parameters like conductivity and winds structure in this region. Seasonal daytime electrojet (EEJ) current strength for June solstice, March and September equinoxes, respectively had peak values ranging within 27-35 nT (at 1400 LT) , 30-40 nT (at 1200 LT) and 35-45 nT (at 1500 LT). The different peak periods of the EEJ strength were attributed to the combined effects of the peak electron density and electric field. Lastly, the EEJ strength was observed to be higher during the equinoxes than the solstice period.

  17. A BaF2 crystal array for high energy-ray measurements

    Indian Academy of Sciences (India)

    Abstract. We shall discuss about the scientific motivation and construction of a 7 × 7 BaF2 crystal array at Variable Energy Cyclotron Centre, Calcutta. This detector would be used to measure high energy -ray photons from GDR decay and proton–neutron bremsstrahlung reactions at the present 88'' cyclotron and upcoming ...

  18. Finding column depedencies in sparse matrices over $ F_ 2 $ by block Wiedemann

    NARCIS (Netherlands)

    O. Penninga

    1998-01-01

    textabstractLarge systems of linear equations over $mathbb{F_2$ with sparse coefficient matrices have to be solved as a part of integer factorization with sieve-based methods such as in the Number Field Sieve algorithm. In this report, we first discuss the Wiedemann algorithm to solve these systems

  19. Luminescence Properties of CaF2 Nanostructure Activated by Different Elements

    Directory of Open Access Journals (Sweden)

    Numan Salah

    2015-01-01

    Full Text Available Nanostructures of calcium fluoride (CaF2 doped with Eu, Tb, Dy, Cu, and Ag were synthesized by the coprecipitation method and studied for their thermoluminescence (TL and photoluminescence (PL properties. The PL emission spectrum of pure CaF2 nanostructure has a broad band in the 370–550 nm range. Similar spectra were observed in case of doped samples, beside extra bands related to these impurities. The maximum PL intensity was observed in Eu doped sample. The TL results of Eu, Cu, Ag, and Tb doped samples show weak glow peaks below 125°C, whereas Dy doped one is found to be highly sensitive with a prominent peak at 165°C. This sample was further exposed to a wide range of gamma rays exposures from 137Cs source. The response curve is linear in the 100 Gy-10 kGy range. It is also observed that the particle size of CaF2 nanostructure was significantly reduced by increasing Dy concentration. These results showed that Dy is a proper activator in the host of CaF2 nanostructure, providing a highly sensitive dosimeter in a wide range of exposures and also plays a role as a controlling agent for particle size growth.

  20. Verification of Ca F2:Mn type of dosemeters for personal dosimetry purposes

    International Nuclear Information System (INIS)

    Misovic, M.; Boskovic, Z.; Spasic-Jokic, V.

    1995-01-01

    Verification results of CaF2:Mn type of dosemeters for personal dosimetry purposes are presented in this paper. Tree types of irradiations are proceeded due to verification of relevant features of TLD. It is concluded that mentioned type of dosemeter can be used for purpose of personal dosimetry. (author)

  1. Fluorine dynamics in BaF2 superionic conductors investigated by NMR

    International Nuclear Information System (INIS)

    Gumann, Patryk

    2008-01-01

    In this work the dynamics of fluorine in solid-state electrolytes having BaF 2 -structure was investigated using three different NMR-methods: field cycling relaxometry, lineshape analysis, and static field gradient NMR. For this purpose a pure BaF 2 crystal, as well as crystals doped with trivalent impurities (LaF 3 ), were studied as a function of temperature. Using MAS NMR it was possible to identify two lines in Ba 0.9 La 0.1 F 2.1 having different chemical shift, and to refer them to the modified crystal structure. On this basis a model for the fluorine lineshape has been developed, taking into account three motional processes characterized by their correlation times. It includes jump diffusion of the fluorine ions among equivalent sites within two crystallographically distinct sublattices, and inter-lattice exchange processes. By measuring frequency and temperature-dependent spin lattice relaxation times, it was possible to gain information about fluorine dynamics on microscopic length scales. An attempt was also made to analyze the data for pure BaF 2 and low admixture concentration samples with a non-exponential correlation function. (orig.)

  2. Calcium flouride (CaF2) from oyster shell as a raw material for thermoluminescence dosimeter

    International Nuclear Information System (INIS)

    Coloma, Lyra C.; Fanuga, Lyn N.; Ocreto, Cherries Ann; Rodriguez, Richita

    2006-03-01

    This study aims to develop a thermoluminescence dosimeter raw material made of calcium fluoride from locally available seashells that is suitable for personal radiation monitoring. Oyster shells were collected and grounded as powder samples and analyzed for calcium fluoride (CaF 2 ) content using XRF and XRD testing. Samples include pure CaF 2 , pure oyster shell, and oyster shells treated with acid. Based from the XRF results, natural oyster shell (w/ and w/o HNO 3 ) had high percentage of calcium about 49.64% and 47.45%, next to the pure calcium fluoride of 51.08%. X-ray diffractrogram shows that oyster sample had the nearest desired structure of CaF 2 compared with two seashells relative to the pure CaF 2 as standard materials. Results show that all of the natural oyster samples displayed TL emission glow curves at the temperature range 200-300 o C. It was also found that pure oyster sample has better TL response as compared to the treated ones. The researchers concluded that the calcium fluoride from oyster shells (without acid and heated) is a potentially good low-cost TLD raw material and may be used as an alternative for the much more expensive LiF dosimeters. (Authors)

  3. Ionospheric foF2 at EIA region: comparison between observations and IRI model

    Science.gov (United States)

    Chuo, Y. J.; Lee, C. C.

    We have used data from an equatorial ionization anomaly area station in the western Pacific region to study the monthly variability of foF2 Diurnal seasonal and solar activity effects were investigated The data established by this study are proposed as valid input values for the development of URSI and CCIR options for the International Reference Ionosphere

  4. Long-term trends in foF2: A comparison of various methods

    Czech Academy of Sciences Publication Activity Database

    Laštovička, Jan; Mikhailov, A. V.; Ulich, T.; Bremer, J.; Elias, A. G.; Ortiz de Adler, N.; Jara, V.; Abarca del Rio, R.; Foppiano, A. J.; Ovalle, E.; Danilov, A. D.

    2006-01-01

    Roč. 68, č. 17 (2006), s. 1854-1870 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : Ionosphere * foF2 * Long-term trends * Anthropogenic effects Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.448, year: 2006

  5. Variability in foF2 at an equatorial station and the influence of magnetic activity

    International Nuclear Information System (INIS)

    Adeniyi, J.O.; Radicella, S.M.

    2003-01-01

    Variability in foF2 is investigated for an equatorial station in the African region. Variability during the day time at high solar activity varies between 10 and 30 percent. It varies between 10 and 20 percent at high solar activity. Magnetic storms increase the variability at both solar activity periods. (author)

  6. When semantics turns to substance: reformulating QCD analysis of F2{γ}(x,Q2)}

    International Nuclear Information System (INIS)

    Chyla, J.

    2000-01-01

    QCD analysis of F 2 {γ} (x,Q 2 ) is revisited. It is emphasized that the presence of the inhomogeneous term in the evolution equations for quark distribution functions of the photon implies important difference in the way factorization mechanism works in photon-hadron and photon-photon collisions as compared to the hadronic ones. Moreover, a careful definitions of the very concepts of the ''leading order'' and ''next-to-leading order'' QCD analysis of F 2 {γ} are needed in order to separate genuine QCD effects from those of pure QED origin. After presenting such definitions, I show that all existing allegedly LO, as well as NLO analyses of F 2 {γ} (x,Q 2 ) are incomplete. The source of this incompleteness of the conventional approach is traced back to the lack of clear identification of QCD effects and to the misinterpretation of the behaviour of q {γ} (x,M) as a function of /α s (M). Complete LO and NLO QCD analyses of F 2 {γ} (x,Q 2 ) are shown to differ substantially from the conventional ones. Whereas complete NLO analysis requires the knowledge of two so far uncalculated quantities, a complete LO one is currently possible, but compared to the conventional formulation requires the inclusion of four known, but in the existing LO analyses unused quantities. The arguments recently advanced in favour of the conventional approach are analyzed and shown to contain a serious flaw. If corrected, they actually lend support to my claim. (author)

  7. Probing the (110)-Oriented plane of rutile ZnF2: A DFT investigation

    Science.gov (United States)

    Tamijani, Ali Abbaspour; Ebrahimiaqda, Elham

    2017-12-01

    For many years, rutile-like crystals have given rise to pronounced enthusiasm amongst mineralogists. In this context, rutile-type ZnF2 has found numerous applications across a variety of disciplines, ranging from material sciences to optoelectronics. Surprisingly, very limited literature is concerned with the molecular adsorption on ZnF2 surfaces and related energetics. Additionally, surface probing with small particles is a well-entrenched technique to analyze the interfacial properties. In this regard, small organic species are valuable picks. In the present work, we have employed electronic structure calculations to simulate the adsorption of methane, chloroform, pyrrole, benzene, naphthalene, anthracene, tetracene and pentacene at the (110) plane of rutile ZnF2. Dispersion-corrected DFT method was chosen to predict the binding energies and structures of molecule-adsorbed surfaces. Interestingly, a linear proportionality relationship was found between the binding energies of aromatic adsorbates and their respective molecular lengths. By applying this relationship, we were able to predict the adsorption energy of pentacene on ZnF2 to within 2% of our DFT-based result.

  8. Measurement of the Neutron F2 Structure Function via Spectator Tagging with CLAS

    Science.gov (United States)

    Baillie, N.; Tkachenko, S.; Zhang, J.; Bosted, P.; Bültmann, S.; Christy, M. E.; Fenker, H.; Griffioen, K. A.; Keppel, C. E.; Kuhn, S. E.; Melnitchouk, W.; Tvaskis, V.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Anghinolfi, M.; Arrington, J.; Avakian, H.; Baghdasaryan, H.; Battaglieri, M.; Biselli, A. S.; Branford, D.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Dey, B.; Djalali, C.; Dodge, G.; Domingo, J.; Doughty, D.; Dupre, R.; Dutta, D.; Ent, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fradi, A.; Gabrielyan, M. Y.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Graham, L.; Guegan, B.; Guidal, M.; Guler, N.; Guo, L.; Hafidi, K.; Heddle, D.; Hicks, K.; Holtrop, M.; Hungerford, E.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ispiryan, M.; Isupov, E. L.; Jawalkar, S. S.; Jo, H. S.; Kalantarians, N.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; King, P. M.; Klein, A.; Klein, F. J.; Klimenko, A.; Kubarovsky, V.; Kuleshov, S. V.; Kvaltine, N. D.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mao, Y.; Markov, N.; McKinnon, B.; Mineeva, T.; Morrison, B.; Moutarde, H.; Munevar, E.; Nadel-Turonski, P.; Ni, A.; Niccolai, S.; Niculescu, I.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L.; Park, K.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Pisano, S.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Ricco, G.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Sober, D. I.; Sokhan, D.; Stepanyan, S.; Stepanyan, S. S.; Stoler, P.; Strauch, S.; Taiuti, M.; Tang, W.; Ungaro, M.; Vineyard, M. F.; Voutier, E.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zana, L.; Zhao, B.

    2012-04-01

    We report on the first measurement of the F2 structure function of the neutron from the semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ≲100MeV/c and their angles to ≳100° relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F2n data collected cover the nucleon-resonance and deep-inelastic regions over a wide range of Bjorken x for 0.65F2n/F2p at 0.2≲x≲0.8 with little uncertainty due to nuclear effects.

  9. Mapping of imprinted quantitative trait loci using immortalized F2 populations.

    Directory of Open Access Journals (Sweden)

    Yongxian Wen

    Full Text Available Mapping of imprinted quantitative trait loci (iQTLs is helpful for understanding the effects of genomic imprinting on complex traits in animals and plants. At present, the experimental designs and corresponding statistical methods having been proposed for iQTL mapping are all based on temporary populations including F2 and BC1, which can be used only once and suffer some other shortcomings respectively. In this paper, we propose a framework for iQTL mapping, including methods of interval mapping (IM and composite interval mapping (CIM based on conventional low-density genetic maps and point mapping (PM and composite point mapping (CPM based on ultrahigh-density genetic maps, using an immortalized F2 (imF2 population generated by random crosses between recombinant inbred lines or doubled haploid lines. We demonstrate by simulations that imF2 populations are very desirable and the proposed statistical methods (especially CIM and CPM are very powerful for iQTL mapping, with which the imprinting effects as well as the additive and dominance effects of iQTLs can be unbiasedly estimated.

  10. Experimental study of the photon structure function F2 in the high Q2 region

    International Nuclear Information System (INIS)

    Bartel, W.; Cords, D.; Dietrich, G.; Dittmann, P.; Eichler, R.; Felst, R.; Haidt, D.; Krehbiel, H.; Meier, K.; Naroska, B.

    1982-09-01

    We report on a measurement of the process e + e - → e + e - + hadrons, where one of the scattered electron is detected at large angles, with an average Q 2 of 23 GeV 2 . The results are analysed in terms of the photon structure function F 2 and are compared with QCD predictions. (orig.)

  11. Simple Y-Autosomal Incompatibilities Cause Hybrid Male Sterility in Reciprocal Crosses Between Drosophila virilis and D. americana

    OpenAIRE

    Sweigart, Andrea L.

    2010-01-01

    Postzygotic reproductive isolation evolves when hybrid incompatibilities accumulate between diverging populations. Here, I examine the genetic basis of hybrid male sterility between two species of Drosophila, Drosophila virilis and D. americana. From these analyses, I reach several conclusions. First, neither species carries any autosomal dominant hybrid male sterility alleles: reciprocal F1 hybrid males are perfectly fertile. Second, later generation (backcross and F2) hybrid male sterility ...

  12. Protein-protein docking with F(2Dock 2.0 and GB-rerank.

    Directory of Open Access Journals (Sweden)

    Rezaul Chowdhury

    Full Text Available Computational simulation of protein-protein docking can expedite the process of molecular modeling and drug discovery. This paper reports on our new F(2 Dock protocol which improves the state of the art in initial stage rigid body exhaustive docking search, scoring and ranking by introducing improvements in the shape-complementarity and electrostatics affinity functions, a new knowledge-based interface propensity term with FFT formulation, a set of novel knowledge-based filters and finally a solvation energy (GBSA based reranking technique. Our algorithms are based on highly efficient data structures including the dynamic packing grids and octrees which significantly speed up the computations and also provide guaranteed bounds on approximation error.The improved affinity functions show superior performance compared to their traditional counterparts in finding correct docking poses at higher ranks. We found that the new filters and the GBSA based reranking individually and in combination significantly improve the accuracy of docking predictions with only minor increase in computation time. We compared F(2 Dock 2.0 with ZDock 3.0.2 and found improvements over it, specifically among 176 complexes in ZLab Benchmark 4.0, F(2 Dock 2.0 finds a near-native solution as the top prediction for 22 complexes; where ZDock 3.0.2 does so for 13 complexes. F(2 Dock 2.0 finds a near-native solution within the top 1000 predictions for 106 complexes as opposed to 104 complexes for ZDock 3.0.2. However, there are 17 and 15 complexes where F(2 Dock 2.0 finds a solution but ZDock 3.0.2 does not and vice versa; which indicates that the two docking protocols can also complement each other.The docking protocol has been implemented as a server with a graphical client (TexMol which allows the user to manage multiple docking jobs, and visualize the docked poses and interfaces. Both the server and client are available for download. Server: http://www.cs.utexas.edu/~bajaj/cvc/software/f

  13. Protein-Protein Docking with F2Dock 2.0 and GB-Rerank

    Science.gov (United States)

    Chowdhury, Rezaul; Rasheed, Muhibur; Keidel, Donald; Moussalem, Maysam; Olson, Arthur; Sanner, Michel; Bajaj, Chandrajit

    2013-01-01

    Motivation Computational simulation of protein-protein docking can expedite the process of molecular modeling and drug discovery. This paper reports on our new F2 Dock protocol which improves the state of the art in initial stage rigid body exhaustive docking search, scoring and ranking by introducing improvements in the shape-complementarity and electrostatics affinity functions, a new knowledge-based interface propensity term with FFT formulation, a set of novel knowledge-based filters and finally a solvation energy (GBSA) based reranking technique. Our algorithms are based on highly efficient data structures including the dynamic packing grids and octrees which significantly speed up the computations and also provide guaranteed bounds on approximation error. Results The improved affinity functions show superior performance compared to their traditional counterparts in finding correct docking poses at higher ranks. We found that the new filters and the GBSA based reranking individually and in combination significantly improve the accuracy of docking predictions with only minor increase in computation time. We compared F2 Dock 2.0 with ZDock 3.0.2 and found improvements over it, specifically among 176 complexes in ZLab Benchmark 4.0, F2 Dock 2.0 finds a near-native solution as the top prediction for 22 complexes; where ZDock 3.0.2 does so for 13 complexes. F2 Dock 2.0 finds a near-native solution within the top 1000 predictions for 106 complexes as opposed to 104 complexes for ZDock 3.0.2. However, there are 17 and 15 complexes where F2 Dock 2.0 finds a solution but ZDock 3.0.2 does not and vice versa; which indicates that the two docking protocols can also complement each other. Availability The docking protocol has been implemented as a server with a graphical client (TexMol) which allows the user to manage multiple docking jobs, and visualize the docked poses and interfaces. Both the server and client are available for download. Server: http://www.cs.utexas.edu/~bajaj/cvc/software/f

  14. Investigation of the conversion mechanism of nanosized CoF2

    International Nuclear Information System (INIS)

    Teng, Yin Ting; Pramana, Stevin S.; Ding, Junfeng; Wu, Tom; Yazami, Rachid

    2013-01-01

    Highlights: • First report on synthesis of nanosized cobalt fluoride via precipitation. • CoF x formation during recharging commences at the interface between cobalt and lithium fluoride. • Valance change of cobalt in cobalt fluoride electrode upon discharging and recharging is shown from EELS and XPS. • Lithiation of CoF 2 leads to formation of superparamagnetic nanosized cobalt particles. • Morphology of the conductive carbon addictives used plays a crucial factor in determining the capacity retention ability. -- Abstract: Nanoparticles (∼20 nm) of tetragonal (P42/mnm) cobalt fluoride (CoF 2 ) has been synthesized by precipitation using cobalt nitrate and ammonium fluoride solution at room temperature, followed by annealing at 400 °C under argon atmosphere. The morphology and structure have been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The electrochemical lithiation of CoF 2 and its structural and valence changes during conversion have been investigated. Electrochemical measurements revealed a discharge specific capacity close to theoretical specific capacity of 553 mAh g −1 and charge specific capacities ranging from 250 to 450 mAh g −1 in the first cycle, depending on the type of conductive carbon addictive used. Lithiation of CoF 2 occurs without any intercalation, but via conversion reaction CoF 2 + 2Li + + 2e − → Co(0) + 2LiF. During lithiation, CoF 2 is fully reduced to Co(0) and breaks down into smaller particles of ∼2 nm. Upon recharging, CoF x is formed instead of CoF 2 . XPS and EELS studies show that only the surface of the electrode is reconverted back to CoF x during recharging. In addition, recharging to form CoF x commences at the interface between the cobalt and lithium fluoride. These results offer the experimental evidence explaining the lack of cycle stability of metal fluorides that undergo a conversion reaction with lithium such

  15. ITO-MgF2 Film Development for PowerSphere Polymer Surface Protection

    Science.gov (United States)

    Hambourger, Paul D.; Kerslake, Thomas W.; Waters, Deborah L.

    2004-01-01

    Multi-kilogram class microsatellites with a PowerSphere electric power system are attractive for fulfilling a variety of potential NASA missions. However, PowerSphere polymer surfaces must be coated with a film that has suitable electrical sheet resistivity for electrostatic discharge control, be resistant to atomic oxygen attack, be transparent to ultraviolet light for composite structure curing and resist ultraviolet light induced darkening for efficient photovoltaic cell operation. In addition, the film must be tolerant of polymer layer folding associated with launch stowage of PowerSphere inflatable structures. An excellent film material candidate to meet these requirements is co-sputtered, indium oxide (In2O3) - tin oxide (SnO2), known as 'ITO', and magnesium fluoride (MgF2). While basic ITO-MgF2 film properties have been the subject of research over the last decade, further research is required in the areas of film durability for space-inflatable applications and precise film property control for large scale commercial production. In this paper, the authors present film durability results for a folded polymer substrate and film resistance to vacuum UV darkening. The authors discuss methods and results in the area of film sheet resistivity measurement and active control, particularly dual-channel, plasma emission line measurement of ITO and MgF2 plasma sources. ITO-MgF2 film polymer coupon preparation is described as well as film deposition equipment, procedures and film characterization. Durability testing methods are also described. The pre- and post-test condition of the films is assessed microscopically and electrically. Results show that an approx. 500A ITO-18vol% MgF2 film is a promising candidate to protect PowerSphere polymer surfaces for Earth orbit missions. Preliminary data also indicate that in situ film measurement methods are promising for active film resistivity control in future large scale production. Future film research plans are also

  16. Comparison of On-line and F2F Education Methods in Teaching Computer Programming

    Directory of Open Access Journals (Sweden)

    Sevinç Gülseçen

    2013-08-01

    Full Text Available lthough online education provides opportunities to people who traditionally do not have access to universities, there is a need for more empirical studies to gain better understanding on how to deliver quality online education, especially when the subject of the course is related with IT. Learning to program is a complicated process. This study aims to find out the difference between students’ performance in online and face-to-face (F2F settings during a computer programming in the fall semester of the year 2010. The study was conducted at the Department of Mathematics, Faculty of Science, Istanbul University. This online course is one of the required courses for students majoring in Mathematics. It is delivered in a learning management system developed in house through a project funded by Istanbul University. The goal is to introduce students with structured programming using the programming language C. Two topics -“Functions in C Programming” and “Loops in C Programming” - were presented to students online and F2F. The total of 62 students formed two groups: the online and F2F groups. The content analysis statistical technique is used, as well as a questionnaire consisting of open-ended questions, which performed as a data collection tool to find out the views of the students in context to the process. While some results concluded that the performance of online students was satisfactory, but that their aggregate final grade was significantly lower than that of students who took an equivalent F2F class, others arrived at a conclusion reporting that there were no significant differences in overall outcomes. In case of making transition from F2F to online mode of teaching, prepossession about a new way of teaching is always an important barrier in students’ perceptions. One of the further researches is investigation of strategies for incorporating blended learning opportunities in programming courses.

  17. Influenza A virus protein PB1-F2 exacerbates IFN-beta expression of human respiratory epithelial cells.

    Science.gov (United States)

    Le Goffic, Ronan; Bouguyon, Edwige; Chevalier, Christophe; Vidic, Jasmina; Da Costa, Bruno; Leymarie, Olivier; Bourdieu, Christiane; Decamps, Laure; Dhorne-Pollet, Sophie; Delmas, Bernard

    2010-10-15

    The PB1-F2 protein of the influenza A virus (IAV) contributes to viral pathogenesis by a mechanism that is not well understood. PB1-F2 was shown to modulate apoptosis and to be targeted by the CD8(+) T cell response. In this study, we examined the downstream effects of PB1-F2 protein during IAV infection by measuring expression of the cellular genes in response to infection with wild-type WSN/33 and PB1-F2 knockout viruses in human lung epithelial cells. Wild-type virus infection resulted in a significant induction of genes involved in innate immunity. Knocking out the PB1-F2 gene strongly decreased the magnitude of expression of cellular genes implicated in antiviral response and MHC class I Ag presentation, suggesting that PB1-F2 exacerbates innate immune response. Biological network analysis revealed the IFN pathway as a link between PB1-F2 and deregulated genes. Using quantitative RT-PCR and IFN-β gene reporter assay, we determined that PB1-F2 mediates an upregulation of IFN-β expression that is dependent on NF-κB but not on AP-1 and IFN regulatory factor-3 transcription factors. Recombinant viruses knocked out for the PB1-F2 and/or the nonstructural viral protein 1 (the viral antagonist of the IFN response) genes provide further evidence that PB1-F2 increases IFN-β expression and that nonstructural viral protein 1 strongly antagonizes the effect of PB1-F2 on the innate response. Finally, we compared the effect of PB1-F2 variants taken from several IAV strains on IFN-β expression and found that PB1-F2-mediated IFN-β induction is significantly influenced by its amino acid sequence, demonstrating its importance in the host cell response triggered by IAV infection.

  18. Gonad morphogenesis defects drive hybrid male sterility in asymmetric hybrid breakdown of Caenorhabditis nematodes.

    Science.gov (United States)

    Dey, Alivia; Jin, Qi; Chen, Yen-Chu; Cutter, Asher D

    2014-01-01

    Determining the causes and evolution of reproductive barriers to gene flow between populations, speciation, is the key to understanding the origin of diversity in nature. Many species manifest hybrid breakdown when they intercross, characterized by increasingly exacerbated problems in later generations of hybrids. Recently, Caenorhabditis nematodes have emerged as a genetic model for studying speciation, and here we investigate the nature and causes of hybrid breakdown between Caenorhabditis remanei and C. latens. We quantify partial F1 hybrid inviability and extensive F2 hybrid inviability; the ~75% F2 embryonic arrest occurs primarily during gastrulation or embryonic elongation. Moreover, F1 hybrid males exhibit Haldane's rule asymmetrically for both sterility and inviability, being strongest when C. remanei serves as maternal parent. We show that the mechanism by which sterile hybrid males are incapable of transferring sperm or a copulatory plug involves defective gonad morphogenesis, which we hypothesize results from linker cell defects in migration and/or cell death during development. This first documented case of partial hybrid male sterility in Caenorhabditis follows expectations of Darwin's corollary to Haldane's rule for asymmetric male fitness, providing a powerful foundation for molecular dissection of intrinsic reproductive barriers and divergence of genetic pathways controlling organ morphogenesis. © 2014 Wiley Periodicals, Inc.

  19. Activation of antitumor immune responses by Ganoderma formosanum polysaccharides in tumor-bearing mice.

    Science.gov (United States)

    Wang, Cheng-Li; Lu, Chiu-Ying; Hsueh, Ying-Chao; Liu, Wen-Hsiung; Chen, Chun-Jen

    2014-11-01

    Fungi of the genus Ganoderma are basidiomycetes that have been used as traditional medicine in Asia and have been shown to exhibit various pharmacological activities. We recently found that PS-F2, a polysaccharide fraction purified from the submerged culture broth of Ganoderma formosanum, stimulates the maturation of dendritic cells and primes a T helper 1 (Th1)-polarized adaptive immune response in vivo. In this study, we investigated whether the immune adjuvant function of PS-F2 can stimulate antitumor immune responses in tumor-bearing mice. Continuous intraperitoneal or oral administration of PS-F2 effectively suppressed the growth of colon 26 (C26) adenocarcinoma, B16 melanoma, and sarcoma 180 (S180) tumor cells in mice without adverse effects on the animals' health. PS-F2 did not cause direct cytotoxicity on tumor cells, and it lost the antitumor effect in mice with severe combined immunodeficiency (SCID). CD4(+) T cells, CD8(+) T cells, and serum from PS-F2-treated tumor-bearing mice all exhibited antitumor activities when adoptively transferred to naïve animals, indicating that PS-F2 treatment stimulates tumor-specific cellular and humoral immune responses. These data demonstrate that continuous administration of G. formosanum polysaccharide PS-F2 can activate host immune responses against ongoing tumor growth, suggesting that PS-F2 can potentially be developed into a preventive/therapeutic agent for cancer immunotherapy.

  20. The complexity of the CaF2:Yb system: evidence that CaF2:Yb2+ is not an impurity trapped exciton system

    Science.gov (United States)

    Mackeen, Cameron; Bridges, Frank; Kozina, Michael; Mehta, Apurva; Reid, M. F.; Wells, J.-P. R.; BarandiaráN, Zoila

    Fluorite crystal structures doped with rare-earth elements exhibit an anomalous redshifted luminescence upon UV excitation, generally attributed to the relaxation of impurity trapped excitons (ITE). We find that the intensity of this luminescence decreases as the total concentration of Yb 2+ increases in unexposed samples, which is in conflict with the currently accepted ITE model. Further, using x-ray absorption spectroscopy and UV-vis studies of CaF2:Yb, we find a large (but reversible) Yb valence reduction upon x-ray exposure at 200 K - from mostly 3+ to 2+. This valence reduction is stable for long time periods at low T ITE model; the data appear more consistent with an intervalence charge transfer (IVCT) model. It is likely that many similar ITE systems have also been misidentified.

  1. EPR study of concentration dependence in Ce, Ce : La and Ce:Y doped SrF2

    NARCIS (Netherlands)

    Dankert, O.; Vainchtein, David; Datema, H.C.; den Hartog, Hendrik

    1995-01-01

    Experimental results of an EPR-study of the concentration dependence of the doubly integrated intensity and linewidth of the signals associated with tetragonal Ce3+-F--dipoles in Sr1-xCexF2+x, Sr-1-0.005-x Ce0.005LaxF2+0.005+x and Sr-1-0.005-x Ce0.005YxF2+0.005+x are presented. Both show a nonlinear

  2. Relationship between vertical ExB drift and F2-layer characteristics in the equatorial ionosphere at solar minimum conditions

    Science.gov (United States)

    Oyekola, Oyedemi S.

    2012-07-01

    Equatorial and low-latitude electrodynamics plays a dominant role in determining the structure and dynamics of the equatorial and low-latitude ionospheric F-region. Thus, they constitute essential input parameters for quantitative global and regional modeling studies. In this work, hourly median value of ionosonde measurements namely, peak height F2-layer (hmF2), F2-layer critical frequency (foF2) and propagation factor M(3000)F2 made at near equatorial dip latitude, Ouagadougou, Burkina Faso (12oN, 1.5oW; dip: 1.5oN) and relevant F2-layer parameters such as thickness parameter (Bo), electron temperature (Te), ion temperature (Ti), total electron content (TEC) and electron density (Ne, at the fixed altitude of 300 km) provided by the International Reference Ionosphere (IRI) model for the longitude of Ouagadougou are contrasted with the IRI vertical drift model to explore in detail the monthly climatological behavior of equatorial ionosphere and the effects of equatorial vertical plasma drift velocities on the diurnal structure of F2-layer parameters. The analysis period covers four months representative of solstitial and equinoctial seasonal periods during solar minimum year of 1987 for geomagnetically quiet-day. We show that month-by-month morphological patterns between vertical E×B drifts and F2-layer parameters range from worst to reasonably good and are largely seasonally dependent. A cross-correlation analysis conducted between equatorial drift and F2-layer characteristics yield statistically significant correlations for equatorial vertical drift and IRI-Bo, IRI-Te and IRI-TEC, whereas little or no acceptable correlation is obtained with observational evidence. Assessment of the association between measured foF2, hmF2 and M(3000)F2 illustrates consistent much more smaller correlation coefficients with no systematic linkage. In general, our research indicates strong departure from simple electrodynamically controlled behavior.

  3. Exploring the Association of Surface Plasmon Resonance with Recombinant MHC:Ig Hybrid Protein as a Tool for Detecting T Lymphocytes in Mice Infected with Leishmania (Leishmania amazonensis

    Directory of Open Access Journals (Sweden)

    Lenilton Silva da Silveira-Júnior

    2017-01-01

    Full Text Available A surface plasmon resonance- (SPR- based recognition method applying H-2 Ld:Ig/peptides complexes for ex vivo monitoring cellular immune responses during murine infection with Leishmania (Leishmania amazonensis is described. Lymphocytes from lesion-draining popliteal lymph nodes were captured on a carboxylated sensor chip surface previously functionalized with H-2 Ld:Ig (DimerX protein bound to synthetic peptides derived from the COOH-terminal region of cysteine proteinase B of L. (L. amazonensis. In computational analysis, these peptides presented values of kinetic constants favorable to form complexes with H-2 Ld at neutral pH, with a Gibbs free energy ΔG°<0. The assayed DimerX:peptide complexes presented the property of attaching to distinct T lymphocytes subsets, obtained from experimentally infected BALB/c mice, in each week of infection, thus indicating a temporal variation in specific T lymphocytes populations, each directed to a different COOH-terminal region-derived peptide. The experimental design proposed herein is an innovative approach for cellular immunology studies of a neglected disease, providing a useful tool for the analysis of specific T lymphocytes subsets.

  4. Pharmacological effects of a synthetic quinoline, a hybrid of tomoxiprole and naproxen, against acute pain and inflammation in mice: a behavioral and docking study

    Directory of Open Access Journals (Sweden)

    Hossein Hosseinzadeh

    2017-04-01

    Full Text Available Objective(s: In the present study, we investigated the potential anti-nociceptive activity and acute anti-inflammatory effect of a synthetic quinoline compound (2-(4-Methoxyphenylbenzo[h]quinoline-4-carboxylic acid, QC, possessing structural elements of both naproxen and tomoxiprole drugs. Materials and Methods: The anti-nociceptive activity of QC was evaluated using chemical- and thermal-induced nociception models and its acute anti-inflammatory effect was evaluated by xylene-induced ear edema test in mice. Results: QC displayed a dose dependent effect in both acute anti-nociceptive tests (writhing and hot plate. This compound at dose of 6.562 mg/kg showed a high anti-nociceptive effect near equal to  diclofenac 5 mg/kg. It also showed high anti-inflammatory effects (less than 6.562 mg/kg comparable to those of reference drugs diclofenac (5 mg/kg and celecoxib (100 mg/kg. Docking study showed that this quinoline derivative could inhibit COX-2 enzyme strongly. Conclusion: QC showed high anti-nociceptive and anti-inflammatory effects comparable to reference drugs and can exert its anti-nociceptive and anti-inflammatory activities through COX-2 inhibition.

  5. Electron paramagnetic resonance and optical absorption of uranium ions diluted in CdF2 single crystals

    International Nuclear Information System (INIS)

    Pereira, J.J.C.R.

    1976-08-01

    The electron paramagnetic resonance (EPR) has been studied in conection with the optical absortion spectra of Uranium ions diluted in CdF 2 single crystals. Analyses of the EPR and optical absorption spectra obtained experimentally, and a comparison with known results in the isomorfic CaF 2 , SrF 2 and BaF 2 , allowed the identification of two paramagnetic centers associated with Uranium ions. These are the U(2+) ion in cubic symmetry having the triplet γ 5 as ground state, and the U(3+) ion in cubic symmetry having the dublet γ 6 as ground state. (Author) [pt

  6. Variation of hmF2 and NmF2 deduced from DPS-4 over Multan (Pakistan) and their comparisons with IRI-2012 & IRI-2016 during the deep solar minimum between cycles 23 & 24

    Science.gov (United States)

    Ameen, Muhammad Ayyaz; Khursheed, Haqqa; Jabbar, Mehak Abdul; Ali, Muneeza Salman; Chishtie, Farrukh

    2018-04-01

    We report the results of ionospheric measurements from DPS-4 installed at Multan (Geog coord. 30.18°N, 71.48°E, dip 47.4°). The variations in F2-layer maximum electron density NmF2 and its peak height hmF2 are studied during the deep solar minimum between cycles 23 & 24 i.e 2008-2009 with comparisons conducted with the International Reference Ionosphere (IRI) versions 2012 & 2016. We find that the hmF2 observations peak around the pre-sunrise and sunrise hours depending on the month. Seasonally, the daytime variation of NmF2 is higher in the Equinox and Summer, while daytime hmF2 are slightly higher in the Equinox and Winter. High values of hmF2 around midnight are caused by an increase of upward drifts produced by meridional winds. The ionosphere over Multan, which lies at the verge of low and mid latitude, is affected by both E × B drifts and thermospheric winds as evident from mid-night peaks and near-sunrise dips in hmF2. The results of the comparison of the observed NmF2 and hmF2 for the year 2008-2009 with the IRI-2012 (both NmF2 and hmF2) and IRI-2016 (only hmF2) estimates indicate that for NmF2, IRI-2012 with Consultative Committee International Radio (CCIR) option produces values in better agreement with observed data. Whereas, for hmF2, IRI-2016 with both International Union of Radio Science (URSI) and CCIR SHU-2015 options, predicts well for nighttime hours throughout the year. However, the IRI-2012 with CCIR option produces better agreement with data during daytime hours. Furthermore, IRI-2012 with CCIR option gives better results during Equinox months, whereas, IRI-2016 with both URSI and CCIR SHU-2015 options predict well for Winter and Summer.

  7. Laser grade CaF2 with controllable properties: growing conditions and structural imperfection

    International Nuclear Information System (INIS)

    Mouchovski, J T; Temelkov, K A; Vuchkov, N K; Sabotinov, N V

    2007-01-01

    Optical properties of CaF 2 , grown by a controlled Bridgman-Stockbarger technique, are studied by CuBr and SrBr 2 vapour lasers. Absorption losses are determined as a function of the grown crystal volume, the crystallization front (CF), and the real crystallization rate. It is found that the absorption losses are relatively independent of the transmitted wavelengths in a wide spectral range from the deep ultraviolet (DUV) to the middle infrared (MIR) spectral region and their minimum corresponds to CF positions within the upper half of the adiabatic furnace zone, where the CR reaches a constant value slightly higher than the speed of crucible movement. The crystal quality conforms to laser grade CaF 2 for the DUV, visible and MIR spectral regions and may be controlled efficiently by introducing an appropriate systematic correction in the furnace temperature field, which shifts the CF position

  8. Immunological comparison of basic encephalitogen and histone F2A1

    International Nuclear Information System (INIS)

    Bustin, M.; Teitelbaum, D.; Webb, C.

    1975-01-01

    The extent of immunological cross-reaction between basic encephalitogen and histone F2A1 on both the humoral antibody level and on the cellular level has been established. The extent of humoral cross-reaction was tested by direct complement fixation employing both anti-histone F2A1 and antisera to basic encephalitogen, by inhibition of complement fixation, by radioimmunoassay and by passive cutaneous anaphylaxis. The data obtained failed to reveal immunological cross-reaction between the proteins on the humoral antibody level. The extent of cross-reaction at the cellular level was tested by the lymphocyte stimulation technique in rabbits and guinea pigs, by inhibition of lymphocyte stimulation and by delayed hypersensitivity skin reactions. It is concluded that the immunological studies provide limited evidence that the two proteins share antigenic determinants. (orig./GSE) [de

  9. Selective cell culture on UV transparent polymer by F2 laser surface modification

    International Nuclear Information System (INIS)

    Hanada, Yasutaka; Sugioka, Koji; Kawano, Hiroyuki; Tsuchimoto, Takayoshi; Miyamoto, Iwao; Miyawaki, Atsushi; Midorikawa, Katsumi

    2009-01-01

    A microchip made of UV transparent polymer (CYTOP) that can perform selective cell culture has been fabricated by F 2 laser surface modification. The refractive index of CYTOP is almost the same as that of culture medium, which is essential for three-dimensional (3D) observation of cells. The F 2 laser modification of CYTOP achieves hydrophilicity only on the laser irradiated area with little deterioration of the optical properties and surface smoothness. After the laser modification, HeLa cells were successfully cultured and strongly adhered only on the modified area of CYTOP. The cells patterned on CYTOP were applied for clear 3D observation using an optical microscope in phase contrast mode.

  10. Leading twist moments of the neutron structure function F_2n

    Energy Technology Data Exchange (ETDEWEB)

    M. Osipenko; W. Melnitchouk; S. Simula; S. Kulagin; G. Ricco

    2005-10-20

    We perform a global analysis of neutron $F_2^n$ structure function data, obtained by combining proton and deuteron measurements over a large range of kinematics. From these data the lowest moments ($n \\leq 10$) of the leading twist neutron $F_2^n$ structure function are extracted. Particular attention is paid to nuclear effects in the deuteron, which become increasingly important for the higher moments. Our results for the nonsinglet, isovector $p - n$ combination of the leading twist moments are compared with those of available lattice simulations. We also determine the lowest few moments of the higher twist contributions, obtained by subtracting the leading twist from the total structure function, and analyze their isospin dependence.

  11. Quenching of scintillation in BaF2 for light charged particles

    International Nuclear Information System (INIS)

    Matulewicz, T.

    1992-01-01

    Detectors made of a barium fluoride (BaF 2 ) crystal have recently become popular in the spectroscopy of photons and light charged particles at intermediate energies. The quenching of the scintillation light of BaF 2 crystals is described in the framework of Birks law for light charged particles in the energy range of 20-100 A MeV. Based on the recently published data, the analysis yields a value of Birks constant equal to 1.8±0.3 mg MeV -1 cm -2 and a scintillation efficiency equal to 0.79±0.05 MeV ee MeV -1 . (R.P.) 10 refs.; 2 figs

  12. F2-laser patterning of indium tin oxide (ITO) thin film on glass substrate

    International Nuclear Information System (INIS)

    Xu, M.Y.; Li, J.; Herman, P.R.; Lilge, L.D.

    2006-01-01

    This paper reports the controlled micromachining of 100 nm thick indium tin oxide (ITO) thin films on glass substrates with a vacuum-ultraviolet 157 nm F 2 laser. Partial to complete film removal was observed over a wide fluence window from 0.49 J/cm 2 to an optimized single pulse fluence of 4.5 J/cm 2 for complete film removal. Optical microscopy, atomic force microscopy, and energy dispersive X-ray analysis show little substrate or collateral damage by the laser pulse which conserved the stoichiometry, optical transparency and electrical conductivity of ITO coating adjacent to the trenches. At higher fluence, a parallel micron sized channel can be etched in the glass substrate. The high photon energy and top-hat beam homogenized optical system of the F 2 laser opens new means for direct structuring of electrodes and microchannels in biological microfluidic systems or in optoelectronics. (orig.)

  13. Measurement of the photon structure function $F_{2}^{\\gamma}$ at low x

    CERN Document Server

    Ackerstaff, K.; Allison, John; Altekamp, N.; Anderson, K.J.; Anderson, S.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Bartoldus, R.; Batley, J.R.; Baumann, S.; Bechtluft, J.; Beeston, C.; Behnke, T.; Bell, A.N.; Bell, Kenneth Watson; Bella, G.; Bentvelsen, S.; Bethke, S.; Biebel, O.; Biguzzi, A.; Bird, S.D.; Blobel, V.; Bloodworth, I.J.; Bloomer, J.E.; Bobinski, M.; Bock, P.; Bonacorsi, D.; Boutemeur, M.; Bouwens, B.T.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Burgard, C.; Burgin, R.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Clarke, P.E.L.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Cuffiani, M.; Dado, S.; Dallapiccola, C.; Dallavalle, G.Marco; Davies, R.; De Jong, S.; del Pozo, L.A.; Desch, K.; Dienes, B.; Dixit, M.S.; do Couto e Silva, E.; Doucet, M.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Eatough, D.; Edwards, J.E.G.; Estabrooks, P.G.; Evans, H.G.; Evans, M.; Fabbri, F.; Fanti, M.; Faust, A.A.; Fiedler, F.; Fierro, M.; Fischer, H.M.; Fleck, I.; Folman, R.; Fong, D.G.; Foucher, M.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gascon, J.; Gascon-Shotkin, S.M.; Geddes, N.I.; Geich-Gimbel, C.; Geralis, T.; Giacomelli, G.; Giacomelli, P.; Giacomelli, R.; Gibson, V.; Gibson, W.R.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Goodrick, M.J.; Gorn, W.; Grandi, C.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Hargrove, C.K.; Hart, P.A.; Hartmann, C.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herndon, M.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hillier, S.J.; Hobson, P.R.; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Hutchcroft, D.E.; Igo-Kemenes, P.; Imrie, D.C.; Ingram, M.R.; Ishii, K.; Jawahery, A.; Jeffreys, P.W.; Jeremie, H.; Jimack, M.; Joly, A.; Jones, C.R.; Jones, G.; Jones, M.; Jost, U.; Jovanovic, P.; Junk, T.R.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kirk, J.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D.S.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kress, T.; Krieger, P.; von Krogh, J.; Kyberd, P.; Lafferty, G.D.; Lahmann, R.; Lai, W.P.; Lanske, D.; Lauber, J.; Lautenschlager, S.R.; Layter, J.G.; Lazic, D.; Lee, A.M.; Lefebvre, E.; Lellouch, D.; Letts, J.; Levinson, L.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menke, S.; Merritt, F.S.; Mes, H.; Meyer, J.; Michelini, A.; Mikenberg, G.; Miller, D.J.; Mincer, A.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Morii, M.; Muller, U.; Mihara, S.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nellen, B.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oh, A.; Oldershaw, N.J.; Oreglia, M.J.; Orito, S.; Palinkas, J.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Pearce, M.J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poffenberger, P.; Poli, B.; Posthaus, A.; Rees, D.L.; Rigby, D.; Robertson, S.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rooke, A.; Ros, E.; Rossi, A.M.; Routenburg, P.; Rozen, Y.; Runge, K.; Runolfsson, O.; Ruppel, U.; Rust, D.R.; Rylko, R.; Sachs, K.; Saeki, T.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schenk, P.; Schieck, J.; Schleper, P.; Schmitt, B.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schultz-Coulon, H.C.; Schumacher, M.; Schwick, C.; Scott, W.G.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Sittler, A.; Skillman, A.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Springer, Robert Wayne; Sproston, M.; Stephens, K.; Steuerer, J.; Stockhausen, B.; Stoll, K.; Strom, David M.; Szymanski, P.; Tafirout, R.; Talbot, S.D.; Tanaka, S.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomson, M.A.; von Torne, E.; Towers, S.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turcot, A.S.; Turner-Watson, M.F.; Utzat, P.; Van Kooten, Rick J.; Verzocchi, M.; Vikas, P.; Vokurka, E.H.; Voss, H.; Wackerle, F.; Wagner, A.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wermes, N.; White, J.S.; Wilkens, B.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

    1997-01-01

    Deep inelastic electron-photon scattering is studied using e+e- data collected by the OPAL detector at centre-of-mass energies sqrt{s_ee} ~ M_{Z^0}. The photon structure function F_2^gamma(x,Q^2) is explored in a Q^2 range of 1.1 to 6.6 GeV/c^2 at lower x values than ever before. To probe this kinematic region events are selected with a beam electron scattered into one of the OPAL luminosity calorimeters at scattering angles between 27 and 55 mrad. A measurement is presented of the photon structure function F_2^gamma(x,Q^2) at = 1.86 GeV^2 and 3.76 GeV^2 in five logarithmic x bins from 0.0025 to 0.2.

  14. B meson spectrum and decay constant from N{sub f}=2 simulations

    Energy Technology Data Exchange (ETDEWEB)

    Blossier, Benoit [Lab. de Physique Theorique, CNRS et Univ. Paris-Sud XI, 91 - Orsay (France); Bulava, John [DESY, Zeuthen (Germany). NIC; Della Morte, Michele [Mainz Univ. (DE), Inst. fuer Kernphysik] (and others)

    2010-12-15

    We report on the status of an ALPHA Collaboration project to extract quantities for B physics phenomenology from N{sub f}=2 lattice simulations. The framework is Heavy Quark Effective Theory (HQET) expanded up to the first order of the inverse b-quark mass. The couplings of the effective theory are determined by imposing matching conditions of observables computed in HQET with their counterpart computed in QCD. That program, based on N{sub f}=2 simulations in a small physical volume with Schroedinger functional boundary conditions, is now almost finished. On the other side the analysis of configurations selected from the CLS ensembles, in order to measure HQET hadronic matrix elements, has just started recently so that only results obtained at a single lattice spacing, a=0:07 fm, is discussed. We give our first results for the b-quark mass and for the B meson decay constant. (orig.)

  15. Comparing AdS/CFT dipole model to HERA F2 data

    International Nuclear Information System (INIS)

    LU Zhun

    2010-01-01

    We apply an AdS/CFT-inspired color-dipole model which contains only three free parameters to describe the HERA data for the inclusive structure function F 2 at small Bjorken-x and virtuality. We found that the saturation scale in our AdS/CFT-based parameterization varies in the range of 1-3 GeV becoming independent of energy/Bjorken-x at very small x. This leads to the prediction of x-independence of the structure functions at very small x. With the fitted parameters in our model, the predictions for F 2 , longitudinal structure function, charm structure function and total photo-production cross-sections in the kinematic regions of future experiments can be given. (authors)

  16. Absence of systemic oxidative stress and increased CSF prostaglandin F2α in progressive MS

    DEFF Research Database (Denmark)

    Lam, Magda A.; Maghzal, Ghassan J.; Khademi, Mohsen

    2016-01-01

    Objective: We aimed to investigate the role of oxidative stress in the progression of multiple sclerosis (MS).  Methods: We determined by liquid chromatography-tandem mass spectrometry nonenzymatic (F2-isoprostanes) and enzymatic oxidation products of arachidonic acid (prostaglandin F2α [PGF2α......]) in plasma and CSF of 45 controls (other neurologic disease [OND] with no signs of inflammation) and 62 patients with MS. Oxidation products were correlated with disease severity and validated biomarkers of inflammation (chemokine ligand 13; matrix metalloproteinase-9; osteopontin) and axonal damage...... with natalizumab and methylprednisolone treatment and was unaffected by the use of nonsteroidal anti-inflammatory drug in secondary progressive MS. CSF PGF2α did not associate with validated CSF markers of inflammation and axonal damage that themselves did not associate with the Expanded Disability Status Scale...

  17. Cloning and characterization of two duplicated interleukin-17A/F2 genes in common carp (Cyprinus carpio L.): Transcripts expression and bioactivity of recombinant IL-17A/F2.

    Science.gov (United States)

    Li, Hongxia; Yu, Juhua; Li, Jianlin; Tang, Yongkai; Yu, Fan; Zhou, Jie; Yu, Wenjuan

    2016-04-01

    Interleukin-17 (IL-17) plays an important role in inflammation and host defense in mammals. In this study, we identified two duplicated IL-17A/F2 genes in the common carp (Cyprinus carpio) (ccIL-17A/F2a and ccIL-17A/F2b), putative encoded proteins contain 140 amino acids (aa) with conserved IL-17 family motifs. Expression analysis revealed high constitutive expression of ccIL-17A/F2s in mucosal tissues, including gill, skin and intestine, their expression could be induced by Aeromonas hydrophila, suggesting a potential role in mucosal immunity. Recombinant ccIL-17A/F2a protein (rccIL-17A/F2a) produced in Escherichia coli could induce the expression of proinflammatory cytokines (IL-1β) and the antimicrobial peptides S100A1, S100A10a and S100A10b in the primary kidney in a dose- and time-dependent manner. Above findings suggest that ccIL-17A/F2 plays an important role in both proinflammatory and innate immunity. Two duplicated ccIL-17A/F2s showed different expression level with ccIL-17A/F2a higher than b, comparison of two 5' regulatory regions indicated the length from anticipated promoter to transcriptional start site (TSS) and putative transcription factor binding site (TFBS) were different. Promoter activity of ccIL-17A/F2a was 2.5 times of ccIL-17A/F2b which consistent with expression results of two genes. These suggest mutations in 5'regulatory region contributed to the differentiation of duplicated genes. To our knowledge, this is the first report to analyze 5'regulatory region of piscine IL-17 family genes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Epistasis between QTLs for bone density variation in Copenhagen × dark agouti F2 rats

    OpenAIRE

    Koller, Daniel L.; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J.; Foroud, Tatiana; Turner, Charles H.

    2009-01-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, o...

  19. Determination of fluoride content in UO2F2 and ADUF solution by ion selective electrode

    International Nuclear Information System (INIS)

    Samanta, Papu; Kumar, Pradeep; Bagchi, A.C.

    2017-01-01

    During production of uranium metal powder, liquid solution UO 2 F 2 and ADUF containing high content of fluoride gets generated. Fluoride being corrosive in nature, fluorides concentration needs to determined. Ion selective electrode, LaF 3 (Eu) crystal, has been used. Uranium was found to interfere with fluoride analysis. Study was carried out to selectively remove uranium by solvent extraction employing D2EHPA+Cyanex 923 and TBP in dodecane. The TBP was found effective to remove uranium. (author)

  20. Synthesis and Physical Properties of the Oxofluoride Cu2(SeO3)F2.

    Science.gov (United States)

    Mitoudi-Vagourdi, Eleni; Papawassiliou, Wassilios; Müllner, Silvia; Jaworski, Aleksander; Pell, Andrew J; Lemmens, Peter; Kremer, Reinhard K; Johnsson, Mats

    2018-04-16

    Single crystals of the new compound Cu 2 (SeO 3 )F 2 were successfully synthesized via a hydrothermal method, and the crystal structure was determined from single-crystal X-ray diffraction data. The compound crystallizes in the orthorhombic space group Pnma with the unit cell parameters a = 7.066(4) Å, b = 9.590(4) Å, and c = 5.563(3) Å. Cu 2 (SeO 3 )F 2 is isostructural with the previously described compounds Co 2 TeO 3 F 2 and CoSeO 3 F 2 . The crystal structure comprises a framework of corner- and edge-sharing distorted [CuO 3 F 3 ] octahedra, within which [SeO 3 ] trigonal pyramids are present in voids and are connected to [CuO 3 F 3 ] octahedra by corner sharing. The presence of a single local environment in both the 19 F and 77 Se solid-state MAS NMR spectra supports the hypothesis that O and F do not mix at the same crystallographic positions. Also the specific phonon modes observed with Raman scattering support the coordination around the cations. At high temperatures the magnetic susceptibility follows the Curie-Weiss law with Curie temperature of Θ = -173(2) K and an effective magnetic moment of μ eff ∼ 2.2 μ B . Antiferromagnetic ordering below ∼44 K is indicated by a peak in the magnetic susceptibility. A second though smaller peak at ∼16 K is tentatively ascribed to a magnetic reorientation transition. Both transitions are also confirmed by heat capacity measurements. Raman scattering experiments propose a structural phase instability in the temperature range 6-50 K based on phonon anomalies. Further changes in the Raman shift of modes at ∼46 K and ∼16 K arise from transitions of the magnetic lattice in accordance with the susceptibility and heat capacity measurements.

  1. Gluons from logarithmic slopes of F2 in the NLL approximation

    International Nuclear Information System (INIS)

    Golec-Biernat, K.

    1994-02-01

    We make a critical, next-to-leading order, study of the accuracy of the ''Prytz'' relation, which is frequently used to extract the gluon distribution at small x from the logarithmic slopes of the structure function F 2 . We find that the simple relation is not generally valid in the HERA regime, but show that it is a reasonable approximation for gluons which are sufficiency singular at small x. (author). 9 refs, 3 figs

  2. T-x projections of phase diagrams of the MeF-BeF2 systems

    International Nuclear Information System (INIS)

    Korenev, Yu.M.; Rykov, A.N.; Novoselova, A.V.

    1976-01-01

    The T-x projections of the state diagrams of the systems MeF-BeF 2 (Me=Li-Rb) have been plotted. Transformation of P-x cross sections of the system state diagrams with decreasing temperature have been considered with the aid, of the general view of T-x projections. The nature of sublimation of the compounds formed in these systems is discussed

  3. New perspectives for undoped CaF2 scintillator as a threshold activation neutron detector

    Science.gov (United States)

    Sibczynski, Pawel; Dziedzic, Andrzej; Grodzicki, Krystian; Iwanowska-Hanke, Joanna; Moszyński, Marek; Swiderski, Lukasz; Syntfeld-Każuch, Agnieszka; Wolski, Dariusz; Carrel, Frédérick; Grabowski, Amélie; Hamel, Matthieu; Laine, Frederic; Sari, Adrien; Iovene, Alessandro; Tintori, Carlo; Fontana, Cristiano; Pino, Felix

    2018-01-01

    In this paper we present the prompt photofission neutron detection performance of undoped CaF2 scintillator using Threshold Activation Detection (TAD). The study is carried out in the frame of C-BORD Horizon 2020 project, during which an efficient toolbox for high volume freight non-intrusive inspection (NII) is under development. Technologies for radiation monitoring are the part of the project. Particularly, detection of various radiological threats on country borders plays an important significant role in Homeland Security applications. Detection of illegal transfer of Special Nuclear Material (SNM) - 235U, 233U and 239Pu - is particular due to the potential use for production of nuclear weapon as well as radiological dispersal device (RDD) V known also as a "dirty bomb". This technique relies on activation of 19F nuclei in the scintillator medium by fast neutrons and registration of high-energy β particles and γ-rays from the decay of reaction products. The radiation from SNM is detected after irradiation in order to avoid detector blinding. Despite the low 19F(n,α)16N or 19F(n,p)19O reaction cross-section, the method could be a good solution for detection of shielded nuclear material. Results obtained with the CaF2 detector were compared with the previous study done for BaF2 and 3He detector. These experimental results were obtained using 252Cf source and 9 MeV Varian Linatron M9 linear accelerator (LINAC). Finally, performance of the prompt neutron detection system based on CaF2 will be validated at Rotterdam Seaport during field trails in 2018.

  4. New perspectives for undoped CaF2 scintillator as a threshold activation neutron detector

    Directory of Open Access Journals (Sweden)

    Sibczynski Pawel

    2018-01-01

    Full Text Available In this paper we present the prompt photofission neutron detection performance of undoped CaF2 scintillator using Threshold Activation Detection (TAD. The study is carried out in the frame of C-BORD Horizon 2020 project, during which an efficient toolbox for high volume freight non-intrusive inspection (NII is under development. Technologies for radiation monitoring are the part of the project. Particularly, detection of various radiological threats on country borders plays an important significant role in Homeland Security applications. Detection of illegal transfer of Special Nuclear Material (SNM - 235U, 233U and 239Pu - is particular due to the potential use for production of nuclear weapon as well as radiological dispersal device (RDD V known also as a “dirty bomb”. This technique relies on activation of 19F nuclei in the scintillator medium by fast neutrons and registration of high-energy β particles and γ-rays from the decay of reaction products. The radiation from SNM is detected after irradiation in order to avoid detector blinding. Despite the low 19F(n,α16N or 19F(n,p19O reaction cross-section, the method could be a good solution for detection of shielded nuclear material. Results obtained with the CaF2 detector were compared with the previous study done for BaF2 and 3He detector. These experimental results were obtained using 252Cf source and 9 MeV Varian Linatron M9 linear accelerator (LINAC. Finally, performance of the prompt neutron detection system based on CaF2 will be validated at Rotterdam Seaport during field trails in 2018.

  5. Refractive indices of CaF2 single crystals under elastic shock loading

    Science.gov (United States)

    Li, Y.; Zhou, X. M.; Liu, C. L.; Luo, S. N.

    2017-07-01

    Refractive indices and Hugoniots of CaF2 single crystals are investigated by laser displacement interferometry under shock loading below 5 GPa. Birefringence is observed for the [110] loading. We obtain the Hugoniot equation of states for [100], [110] and [111], and refractive indices for these orientations with consideration of their polarization. The measured refractive indices are in reasonable agreement with predictions based on the piezo-optic theory, and are used to refine the elasto-optic coefficients.

  6. Nucleon scalar matrix elements with N{sub f}=2+1+1 twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Dinter, Simon; Drach, Vincent; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC

    2011-12-15

    We investigate scalar matrix elements of the nucleon using N{sub f}=2+1+1 flavors of maximally twisted mass fermions at a fixed value of the lattice spacing of a{approx}0.078 fm. We compute disconnected contributions to the relevant three-point functions using an efficient noise reduction technique. Using these methods together with an only multiplicative renormalization applicable for twisted mass fermions, allows us to obtain accurate results in the light and strange sector. (orig.)

  7. Frictional Heating of Ions In The F2-region of The Ionosphere

    Science.gov (United States)

    Zhizhko, G. O.; Vlasov, V. G.

    Auroral electron beams unstable on the Cherenkov resonance are stabilized by large- scale inhomogeneity of the plasma density during all their way from the acceleration region to the E-region of the ionosphere. The generation of plasma waves by beam is possible only in the region of small plasma density gradients, that always is the area of the F2-region maximum. Thus, collective dissipation of the electron beam energy occurs in the local region with the length about several tens of kilometers. This leads to the intensive heating of the electrons(up to temperatures about 10000 K) and will give origin to the ion upflows with velocity about 1 km/s and density about 109 cm-2 s-1. These flows can result in the ion frictional heating. At the same time ion temperatures reach the values about 5000 K. A numerical simulation of the ion frictional heating in the presence of collective elec- tron heating in the high-latitude F2-region of the ionosphere was performed. The sim- ulation has shown that the most critical parameter for the occurence of the ion fric- tional heating was the the steepness of the plasma density profile above the F2-region maximum.

  8. Photoionization study of the F2+ ion via the screening constant by unit nuclear charge method

    Science.gov (United States)

    Dieng, M.; Tine, M.; Sow, M.; Diop, B.; Guèye, M.; Faye, M.; Sakho, I.; Biaye, M.; Wagué, A.

    2014-03-01

    In this paper, we have tabulated energy resonances of the 2s22p2 (1D)nd (2L), 2s22p2 (1S)nd (2L) and 2s22p3 (3D)np Rydberg series originating from the 2s22p3(2Po) and from the 2s22p3 (2Do) metastable states of F2+. In addition, energy resonances of the 2s2p3(5So)np (4P) Rydberg series originating from the 2s22p3 (4So) ground-state of F2+are also reported. Calculations are performed using the Screening constant by unit nuclear charge (SCUNC) method. Analysis of the present data is achieved by calculating the quantum defects and the effective nuclear charges for each series. The present results agree very well with the Advanced Light Source experiments on F2+ (Aguilar et al., 2005). Upto n=30, the present quantum defects are almost constant and the effective charge decreases regularly toward the electric charge of the F3+ core ion along each series.

  9. The investigation on electrochemical reaction mechanism of CuF2 thin film with lithium

    International Nuclear Information System (INIS)

    Cui Yanhua; Xue Mingzhe; Zhou Yongning; Peng Shuming; Wang Xiaolin; Fu Zhengwen

    2011-01-01

    Crystalline CuF 2 thin films were prepared by pulsed laser deposition under room temperature. The physical and electrochemical properties of the as-deposited thin films have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic cycling and cyclic voltammetry (CV). Reversible capacity of 544 mAh g -1 was achieved in the potential range of 1.0-4.0 V. A reversible couple of redox peaks at 3.0 V and 3.7 V was firstly observed. By using ex situ XRD and TEM techniques, an insertion process followed by a fully conversion reaction to Cu and LiF was revealed in the lithium electrochemical reaction of CuF 2 thin film electrode. The reversible insertion reaction above 2.8 V could provide a capacity of about 125 mAh g -1 , which makes CuF 2 a potential cathode material for rechargeable lithium batteries.

  10. Inner-shell photoionization and core-hole decay of Xe and XeF2.

    Science.gov (United States)

    Southworth, Stephen H; Wehlitz, Ralf; Picón, Antonio; Lehmann, C Stefan; Cheng, Lan; Stanton, John F

    2015-06-14

    Photoionization cross sections and partial ion yields of Xe and XeF2 from Xe 3d(5/2), Xe 3d(3/2), and F 1s subshells in the 660-740 eV range are compared to explore effects of the F ligands. The Xe 3d-ϵf continuum shape resonances dominate the photoionization cross sections of both the atom and molecule, but prominent resonances appear in the XeF2 cross section due to nominal excitation of Xe 3d and F 1s electrons to the lowest unoccupied molecular orbital (LUMO), a delocalized anti-bonding MO. Comparisons of the ion products from the atom and molecule following Xe 3d photoionization show that the charge-state distribution of Xe ions is shifted to lower charge states in the molecule along with production of energetic F(+) and F(2+) ions. This suggests that, in decay of a Xe 3d core hole, charge is redistributed to the F ligands and the system dissociates due to Coulomb repulsion. The ion products from excitation of the F 1s-LUMO resonance are different and show strong increases in the yields of Xe(+) and F(+) ions. The subshell ionization thresholds, the LUMO resonance energies, and their oscillator strengths are calculated by relativistic coupled-cluster methods and agree well with measurements.

  11. A new ionospheric storm scale based on TEC and foF2 statistics

    Science.gov (United States)

    Nishioka, Michi; Tsugawa, Takuya; Jin, Hidekatsu; Ishii, Mamoru

    2017-01-01

    In this paper, we propose the I-scale, a new ionospheric storm scale for general users in various regions in the world. With the I-scale, ionospheric storms can be classified at any season, local time, and location. Since the ionospheric condition largely depends on many factors such as solar irradiance, energy input from the magnetosphere, and lower atmospheric activity, it had been difficult to scale ionospheric storms, which are mainly caused by solar and geomagnetic activities. In this study, statistical analysis was carried out for total electron content (TEC) and F2 layer critical frequency (foF2) in Japan for 18 years from 1997 to 2014. Seasonal, local time, and latitudinal dependences of TEC and foF2 variabilities are excluded by normalizing each percentage variation using their statistical standard deviations. The I-scale is defined by setting thresholds to the normalized numbers to seven categories: I0, IP1, IP2, IP3, IN1, IN2, and IN3. I0 represents a quiet state, and IP1 (IN1), IP2 (IN2), and IP3 (IN3) represent moderate, strong, and severe positive (negative) storms, respectively. The proposed I-scale can be used for other locations, such as polar and equatorial regions. It is considered that the proposed I-scale can be a standardized scale to help the users to assess the impact of space weather on their systems.

  12. Synthesis and Characterization of Nd(3+)-Doped CaF2 Nanoparticles.

    Science.gov (United States)

    Yuan, Dan; Li, Weiwei; Mei, Bingchu; Song, Jinghong

    2015-12-01

    The Ca(1-x)F(2+x):Nd(x) nanoparticles were synthesized by chemical direct precipitation method. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Image analyzer, absorption spectrum and transmittance were taken to characterization the phases, morphologies, sizes, size distribution and optical properties of the samples. The results indicate that the Ca(1-x)F(2+x):Nd(x) samples can be rationally modified in size and morphology by altering the Nd3+ ions doping concentration. With increasing concentration of Nd3+ ions, the particle size decreased from 24 to 14 nm, the intensity of the diffraction peaks decreased, the Ca(1-x)F(2+x):Nd(x) particles aggregated ion of the formed clusters which should have an effect on both speed and orientation of the particles growth. The transmittance of ceramics with a thickness of 2 mm showed that the transmittance can reach 90% when the doping concentration was 5%, which should be profitable for LD pumping.

  13. Mechanoluminescence by impulsive deformation of γ-irradiated Er-doped CaF2 crystals

    International Nuclear Information System (INIS)

    Brahme, Nameeta; Shukla, Manju; Bisen, D.P.; Kurrey, U.; Choubey, Anil; Kher, R.S.; Singh, Manisha

    2011-01-01

    An impulsive technique has been used for mechanoluminescence (ML) measurements in γ-irradiated Er doped CaF 2 crystals. When the ML is excited impulsively by the impact of moving piston on to γ-irradiated CaF 2 :Er crystals, two peaks are observed in ML intensity with time and it is seen that the peak intensities of first and second peaks (I m1 and I m2 ) increase with increasing impact velocity. However the time corresponding to first and second peaks (t m1 and t m2 ) shifts towards shorter time values with increasing impact velocity. It is also seen that the total ML intensity I Total initially increases with the impact velocity and then it attains a saturation value for higher values of the impact velocity. We have presented a theoretical explanation for the observed results. - Research highlights: → Impulsive technique has been used for mechanoluminescence (ML) studies in γ-irradiated Er doped CaF 2 crystals. → ML intensity exhibited two peaks with time (I m1 and I m2 ), where the intensity of both the peaks increased with increasing impact velocity. → The time of occurrence of the peaks (t m1 and t m2 ) reduced with increasing the impact velocity. → Total ML intensity (I Total ) first increases and then attains a saturation value with an increment in the impact velocity. → A theoretical explanation is presented to the observed results.

  14. The proton and deuteron F2 structure function at low Q2

    International Nuclear Information System (INIS)

    Tvaskis, Vladas; Arrington, John; Asaturyan, Razmik; Baker, Oliver; Blok, Henk; Bosted, Peter; Boswell, Melissa; Bruell, Antje; Christy, Michael; Cochran, Anthony; Ent, Rolf; Filippone, Bradley; Gasparian, Ashot; Keppel, Cynthia; Kinney, Edward; Lapikas, L.; Lorenzon, Wolfgang; Mack, David; Mammei, Juliette; Martin, J.W.; Mkrtchyan, Hamlet; Niculescu, Maria-Ioana; Piercey, Rodney; Potterveld, David; Smith, Gregory; Spurlock, Kurt; Van der Steenhoven, Gerard; Stepanyan, Stepan; Tadevosyan, Vardan; Wood, Stephen

    2010-01-01

    Measurements of the proton and deuteron F2 structure functions are presented. The data, taken at Jefferson Lab Hall C, span the four-momentum transfer range 0:06 < Q2 < 2:8 GeV2, and Bjorken x values from 0.009 to 0.45, thus extending the knowledge of F2 to low values of Q2 at low x. Next-to-next-to-leading order calculations using recent parton distribution functions start to deviate from the data for Q2 < 2 GeV2 at the low and high x-values. Down to the lowest value of Q2, the structure function is in good agreement with a parameterization of F2 based on data that have been taken at much higher values of Q2 or much lower values of x, and which is constrained by data at the photon point. The ratio of the deuteron and proton structure functions at low x remains well described by a logarithmic dependence on Q2 at low Q2.

  15. Pyramidal pits created by single highly charged ions in BaF2 single crystals

    International Nuclear Information System (INIS)

    El-Said, A. S.; Heller, R.; Facsko, S.; Aumayr, F.

    2010-01-01

    In various insulators, the impact of individual slow highly charged ions (eV-keV) creates surface nanostructures, whose size depends on the deposited potential energy. Here we report on the damage created on a cleaved BaF 2 (111) surface by irradiation with 4.5xq keV highly charged xenon ions from a room-temperature electron-beam ion trap. Up to charge states q=36, no surface topographic changes on the BaF 2 surface are observed by scanning force microscopy. The hidden stored damage, however, can be made visible using the technique of selective chemical etching. Each individual ion impact develops into a pyramidal etch pits, as can be concluded from a comparison of the areal density of observed etch pits with the applied ion fluence (typically 10 8 ions/cm 2 ). The dimensional analysis of the measured pits reveals the significance of the deposited potential energy in the creation of lattice distortions/defects in BaF 2 .

  16. A novel decomposition technique of friable asbestos by CHClF2-decomposed acidic gas

    International Nuclear Information System (INIS)

    Yanagisawa, Kazumichi; Kozawa, Takahiro; Onda, Ayumu; Kanazawa, Masazumi; Shinohara, Junichi; Takanami, Tetsuro; Shiraishi, Masatsugu

    2009-01-01

    Asbestos was widely used in numerous materials and building products due to their desirable properties. It is, however, well known that asbestos inhalation causes health damage and its inexpensive decomposition technique is necessary to be developed for pollution prevention. We report here an innovative decomposition technique of friable asbestos by acidic gas (HF and HCl) generated from the decomposition of CHClF 2 by the reaction with superheated steam at 800 deg. C. Chrysotile-asbestos fibers were completely decomposed to sellaite and magnesium silicofluoride hexahydrate by the reaction with CHClF 2 -decomposed acidic gas at 150 deg. C for 30 min. At high temperatures beyond 400 deg. C, sellaite and hematite were detected in the decomposed product. In addition, crocidolite containing wastes and amosite containing wastes were decomposed at 500 deg. C and 600 deg. C for 30 min, respectively, by CHClF 2 -decomposed acidic gas. The observation of the reaction products by phase-contrast microscopy (PCM) and scanning electron microscopy (SEM) confirmed that the resulting products did not contain any asbestos

  17. Ion conductivities of ZrF4-BaF2-CsF glasses

    International Nuclear Information System (INIS)

    Kawamoto, Yoji; Nohara, Ichiro

    1987-01-01

    The glass-forming region in the ZrF 4 -BaF 2 -CsF glass system has been determined and the ac conductivity and the transport number of fluoride ions have been measured. The conductivities of compounds β-Cs 2 ZrF 6 , α-SrZrF 6 , α-BaZrF 6 , β-BaZrF 6 and α-PbZrF 6 have also been measured. These results and a previous study of ZrF 4 -BaF 2 -MF n (M: the groups I-IV metals) glasses revealed the following: (1) the ZrF 4 -BaF 2 -CsF glasses are exclusively fluoride-ion conductors; (2) the ionic conductivities of ZrF 4 -based glasses are predominantly determined by the activation energies for conduction; (3) the activation energy for conduction decreases with an increase in the average polarizability of glass-constituting cations; (4) a decrease in average Zr-F bond length and a lowering of the average F coordination number of Zr are presumed to increase the activation energy for conduction. Principles of developing ZrF 4 -based glasses with higher conductivities have also been proposed. (Auth.)

  18. Scintillation and optical stimulated luminescence of Ce-doped CaF2

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Fujimoto, Yutaka; Watanabe, Kenichi; Fukuda, Kentaro; Kawaguchi, Noriaki; Miyamoto, Yuka; Nanto, Hidehito

    2014-01-01

    Scintillation and optical stimulated luminescence of Ce 0.1–20% doped CaF 2 crystals prepared by Tokuyama Corp. were investigated. In X-ray induced scintillation spectra, luminescence due to Ce 3+ 5d–4f transition appeared around 320 nm with typically 40 ns decay time. By 241 Am 5.5 MeV α-ray irradiation, 0.1% doped one showed the highest scintillation light yield and the light yield monotonically decreased with Ce concentrations. Optically stimulated luminescence after X-ray irradiation was observed around 320 nm under 550 or 830 nm stimulation in all samples. As a result, intensities of optically stimulated luminescence were proportional to Ce concentrations. Consequently, scintillation and optically stimulated luminescence resulted to have a complementary relation in Ce-doped CaF 2 system. - Highlights: • Optical, scintillation, and OSL properties of Ce 0.1–20% doped CaF 2 were studied. • Scintillation light yield exhibited inverse proportionality to Ce concentrations. • OSL intensities showed proportionality to Ce concentrations. • Complementary relation of scintillation and OSL was experimentally confirmed

  19. Oestrous synchronization and fertility in cycling Damascus does using the synthetic prostaglandin F2α, iliren

    International Nuclear Information System (INIS)

    Zarkawi, M.

    2008-01-01

    To assess the effect of synthetic prostaglandin F2α (PGF2α) Iliren, on oestrous synchronisation and other related parameters, 9 intact indigenous Damascus does each were either intramuscularly injected twice with 2 ml of synthetic prostaglandin F2α, Iliren (0.3 mg Tiaprost) at an interval of 12 d (P) or served as control (C) with no treatments. Doses in group P responded to the treatment and exhibited oestrus at an average of 96 h; whereas, does in group C exhibited oestrus at an average of 199 h after bucks introduction. The treatment had no significant effect (P>0.05) on duration of pregnancy, fecundity rate of does, birth or weaning weight of kids at 3 months of age. At the second injection of PGF2α, there were active corpora lutea formed in some ovaries of the does treated with Iliren as indicated by the high concentration of progesterone. It could be concluded that it is possible to use the synthetic prostaglandin F2α, Iliren, at a dose of 2 ml (0.3 mg Tiaprost) given twice at an interval of 12 d for oestrous synchronisation in local Damascus does during the breeding season with no adverse effect on the reproductive or growth parameters. (author)

  20. Influence of SrF_2-doping in AlN ceramics on scintillation and dosimeter properties

    International Nuclear Information System (INIS)

    Kojima, Kaori; Okada, Go; Fukuda, Kentaro; Yanagida, Takayuki

    2016-01-01

    In this study, we synthesized undoped AlN and SrF_2-doped AlN (AlN-SrF_2) ceramics by Spark Plasma Sintering (SPS), and we characterized their optical, scintillation and dosimeter properties. The prepared undoped AlN ceramic had gray color and visually non-transparent whereas, with an addition of SrF_2, the transparency improved and became translucent. The measured in-line transmittance was approximately 0.2% at wavelengths longer than 500 nm. While the addition of SrF_2 decreased the scintillation intensity, the decay time was significantly fastened, which is a great advantage for fast photon counting-based measurements. Both the thermally-stimulated luminescence (TSL) and optically-stimulated luminescence (OSL) showed good linear response from the milli-gray range to over 10 Gy. The sensitivity seems to decrease by an addition of SrF_2 as it suppresses structural defect centers which are responsible for dosimeter properties. However, the main TSL glow peak position shifts to higher temperature with the addition of SrF_2, which indicates that inclusion of SrF_2 improves the TSL signal stability. - Highlights: • We synthesized undoped and SrF_2-doped AlN ceramics by Spark Plasma Sintering. • We evaluated scintillator and dosimeter properties of undoped and SrF_2-doped AlN. • By doping with SrF_2, the decay time is shortened. • By doping with SrF_2, the stability of TSL and OSL is improved.

  1. Upgrading CCIR's fo F 2 maps using available ionosondes and genetic algorithms

    Science.gov (United States)

    Gularte, Erika; Carpintero, Daniel D.; Jaen, Juliana

    2018-04-01

    We have developed a new approach towards a new database of the ionospheric parameter fo F 2 . This parameter, being the frequency of the maximum of the ionospheric electronic density profile and its main modeller, is of great interest not only in atmospheric studies but also in the realm of radio propagation. The current databases, generated by CCIR (Committee Consultative for Ionospheric Radiowave propagation) and URSI (International Union of Radio Science), and used by the IRI (International Reference Ionosphere) model, are based on Fourier expansions and have been built in the 60s from the available ionosondes at that time. The main goal of this work is to upgrade the databases by using new available ionosonde data. To this end we used the IRI diurnal/spherical expansions to represent the fo F 2 variability, and computed its coefficients by means of a genetic algorithm (GA). In order to test the performance of the proposed methodology, we applied it to the South American region with data obtained by RAPEAS (Red Argentina para el Estudio de la Atmósfera Superior, i.e. Argentine Network for the Study of the Upper Atmosphere) during the years 1958-2009. The new GA coefficients provide a global better fit of the IRI model to the observed fo F 2 than the CCIR coefficients. Since the same formulae and the same number of coefficients were used, the overall integrity of IRI's typical ionospheric feature representation was preserved. The best improvements with respect to CCIR are obtained at low solar activities, at large (in absolute value) modip latitudes, and at night-time. The new method is flexible in the sense that can be applied either globally or regionally. It is also very easy to recompute the coefficients when new data is available. The computation of a third set of coefficients corresponding to days of medium solar activity in order to avoid the interpolation between low and high activities is suggested. The same procedure as for fo F 2 can be perfomed to

  2. Some AFLP amplicons are highly conserved DNA sequences mapping to the same linkage groups in two F2 populations of carrot

    Directory of Open Access Journals (Sweden)

    Santos Carlos A.F.

    2002-01-01

    Full Text Available Amplified fragment length polymorphism (AFLP is a fast and reliable tool to generate a large number of DNA markers. In two unrelated F2 populations of carrot (Daucus carota L., Brasilia x HCM and B493 x QAL (wild carrot, it was hypothesized that DNA 1 digested with the same restriction endonuclease enzymes and amplified with the same primer combination and 2 sharing the same position in polyacrylamide gels should be conserved sequences. To test this hypothesis AFLP fragments from polyacrylamide gels were eluted, reamplified, separated in agarose gels, purified, cloned and sequenced. Among thirty-one paired fragments from each F2 population, twenty-six had identity greater than 91% and five presented identity of 24% to 44%. Among the twenty-six conserved AFLPs only one mapped to different linkage groups in the two populations while four of the five less-conserved bands mapped to different linkage groups. Of eight SCAR (sequence characterized amplified regions primers tested, one conserved AFLP resulted in co-dominant markers in both populations. Screening among 14 carrot inbreds or cultivars with three AFLP-SCAR primers revealed clear and polymorphic PCR products, with similar molecular sizes on agarose gels. The development of co-dominant markers based on conserved AFLP fragments will be useful to detect seed mixtures among hybrids, to improve and to merge linkage maps and to study diversity and phylogenetic relationships.

  3. Growth of congruently melting Ca0.59Sr0.41F2 crystals and study of their properties

    Science.gov (United States)

    Karimov, D. N.; Komar'kova, O. N.; Sorokin, N. I.; Bezhanov, V. A.; Chernov, S. P.; Popov, P. A.; Sobolev, B. P.

    2010-05-01

    Homogeneous crystals of Ca0.59Sr0.41F2 alloy (sp. gr., Fm bar 3 m, a = 0.56057 nm), corresponding to the point of minimum in the melting curve in the CaF2-SrF2 phase diagram, have been grown by the vertical Bridgman method. The optical, mechanical, electrical, and thermophysical properties of Ca0.59Sr0.41F2 and MF2 crystals ( M = Ca, Sr) have been studied and comparatively analyzed. Ca0.59Sr0.41F2 crystals are transparent in the range of 0.133-11.5 μm, have refractive index n D = 1.436, microhardness H μ = 2.63 ± 0.10 GPa, ion conductivity σ = 5 × 10-5 S/cm at 825 K, and thermal conductivity k = 4.0 W m-1 K-1 at 300 K. It is shown that the optical properties of Ca0.59Sr0.41F2 crystals are intermediate between those of CaF2 and SrF2, whereas their mechanical and electrical characteristics are better than the latter compounds.

  4. Hexafluoridophosphate partial hydrolysis leading to the one-dimensional coordination polymer [{Cu(xantphos)(µ-PO2F2)}n

    OpenAIRE

    Keller, S.; Brunner, F.; Prescimone, A.; Constable, E. C.; Housecroft, C. E.

    2015-01-01

    The one-dimensional coordination polymer [{Cu(xantphos)(μ-PO2F2)}n] (xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene) is reported, the first extended structure in which copper(I) centres are linked by μ-PO2F2 units.

  5. A Theoretical Framework for Association Studies in F2 Family Pools Using Allele Frequencies from Genotyping-By-Sequencing

    DEFF Research Database (Denmark)

    Janss, Luc L; Ashraf, Bilal H; Greve-Pedersen, Morten

    a sequencing approach to obtain Single Nucleotide Polymorphisms (SNPs) frequencies is considered here. In this work we develop the theoretical framework to perform association studies using allele frequencies from such F2 family pools. We show that expected allele frequencies in the F2 families will have...

  6. 78 FR 69778 - Adjustments to Limitations on Designated School Official Assignment and Study by F-2 and M-2...

    Science.gov (United States)

    2013-11-21

    ... to attract the best and brightest international students to study in our schools. Access of F-2 or M... change existing regulations allowing full-time study by children in elementary or secondary school... best and brightest international students to study in our schools. The ability of F-2 or M-2...

  7. Gas phase UV and IR absorption spectra of CxF2x+1CHO (x=1-4)

    DEFF Research Database (Denmark)

    Hashikawa, Y; Kawasaki, M; Waterland, RL

    2004-01-01

    The UV and IR spectra of CxF2x+1 CHO (x = 1-4) were investigated using computational and experimental techniques. CxF2x+1CHO (x = 1-4) have broad UV absorption features centered at 300-310 nm. The maximum absorption cross-section increases significantly and shifts slightly to the red with increased...

  8. Ionic thermocurrents and ionic conductivity of solid solutions of SrF2 and YbF3

    NARCIS (Netherlands)

    Meuldijk, J.; Hartog, den H.W.

    1983-01-01

    We report dielectric [ionic thermocurrent (!TC)] experiments and ionic conductivity of cubic solid solutions of the type Sr1-xYbxF2+x. These combined experiments provide us with new information concerning the ionic conductivity mechanisms which play an important role in solid solutions Sr1-xRxF2+x

  9. Old Yellow Enzyme from Trypanosoma cruzi Exhibits In Vivo Prostaglandin F2α Synthase Activity and Has a Key Role in Parasite Infection and Drug Susceptibility

    Directory of Open Access Journals (Sweden)

    Florencia Díaz-Viraqué

    2018-03-01

    Full Text Available The discovery that trypanosomatids, unicellular organisms of the order Kinetoplastida, are capable of synthesizing prostaglandins raised questions about the role of these molecules during parasitic infections. Multiple studies indicate that prostaglandins could be related to the infection processes and pathogenesis in trypanosomatids. This work aimed to unveil the role of the prostaglandin F2α synthase TcOYE in the establishment of Trypanosoma cruzi infection, the causative agent of Chagas disease. This chronic disease affects several million people in Latin America causing high morbidity and mortality. Here, we propose a prokaryotic evolutionary origin for TcOYE, and then we used in vitro and in vivo experiments to show that T. cruzi prostaglandin F2α synthase plays an important role in modulating the infection process. TcOYE overexpressing parasites were less able to complete the infective cycle in cell culture infections and increased cardiac tissue parasitic load in infected mice. Additionally, parasites overexpressing the enzyme increased PGF2α synthesis from arachidonic acid. Finally, an increase in benznidazole and nifurtimox susceptibility in TcOYE overexpressing parasites showed its participation in activating the currently anti-chagasic drugs, which added to its observed ability to confer resistance to hydrogen peroxide, highlights the relevance of this enzyme in multiple events including host–parasite interaction.

  10. Advantages of CaF2 over ZnS in an α-particle scintillation detector

    International Nuclear Information System (INIS)

    Sabol, B.; Schery, S.D.

    1981-01-01

    Results are reported for using a europium-activated calcium fluoride (CaF 2 ) scintillation crystal as a α-particle detector in a two-filter monitor of atmospheric radon. CaF 2 detectors are cheaper and can cover a larger surface area than the higher-resolution solid-state detectors. Compared to ZnS scintillators, the energy resolution for CaF 2 is improved from 3.0 MeV to 1.1 MeV for 4.7 MeV α-particles; however the light output from CaF 2 is considerably lower. It is concluded that a thin CaF 2 crystal is a cost-effective method of improving energy and time resolutions for the two-filter monitor. (U.K.)

  11. Inclusive f2(1270) meson production in νp and anti νp charged current interactions

    International Nuclear Information System (INIS)

    Jones, G.T.; Jones, R.W.L.; Kennedy, B.W.; Morrison, D.R.O.; Mobayyen, M.M.; Wainstein, S.; Aderholz, M.; Hantke, D.; Hoffmann, E.; Katz, U.F.; Kern, J.; Schmitz, N.; Wittek, W.; Borner, H.P.; Myatt, G.; Radojicic, D.; Burke, S.

    1991-01-01

    Using data obtained with the bubble chamber BEBC at CERN, the inclusive f 2 (1270) meson production in νp and anti νp charged current reactions is studied. It is found that f 2 production occurs mainly in events with a hadronic invariant mass W> or approx.7 GeV. In these events, the average f 2 multiplicity is about half the average ρ 0 multiplicity, and the x F and p T 2 distributions of the f 2 agree in shape with those of the ρ 0 . The predictions of a semi-empirical model (Wells model) are in accord with the measured multiplicities at W>7 GeV, whereas at lower W the model predicts too large f 2 multiplicities. (orig.)

  12. Interfacial chemical bonding state and band alignment of CaF2/hydrogen-terminated diamond heterojunction

    International Nuclear Information System (INIS)

    Liu, J. W.; Liao, M. Y.; Cheng, S. H.; Imura, M.; Koide, Y.

    2013-01-01

    CaF 2 films are deposited on hydrogen-terminated diamond (H-diamond) by a radio-frequency sputter-deposition technique at room temperature. Interfacial chemical bonding state and band alignment of CaF 2 /H-diamond heterojunction are investigated by X-ray photoelectron spectroscopy. It is confirmed that there are only C-Ca bonds at the CaF 2 /H-diamond heterointerface. Valence and conductance band offsets of the CaF 2 /H-diamond heterojunciton are determined to be 3.7 ± 0.2 and 0.3 ± 0.2 eV, respectively. It shows a type I straddling band configuration. The large valence band offset suggests advantage of the CaF 2 /H-diamond heterojunciton for the development of high power and high frequency field effect transistors.

  13. The Relationship between Ionospheric Slab Thickness and the Peak Density Height, hmF2

    Science.gov (United States)

    Meehan, J.; Sojka, J. J.

    2017-12-01

    The electron density profile is one of the most critical elements in the ionospheric modeling-related applications today. Ionosphere parameters, hmF2, the height of the peak density layer, and slab thickness, the ratio of the total electron content, TEC, to the peak density value, NmF2, are generally obtained from any global sounding observation network and are easily incorporated into models, theoretical or empirical, as numerical representations. Slab thickness is a convenient one-parameter summary of the electron density profile and can relate a variety of elements of interest that effect the overall electron profile shape, such as the neutral and ionospheric temperatures and gradients, the ionospheric composition, and dynamics. Using ISR data from the 2002 Millstone Hill ISR data campaign, we found, for the first time, slab thickness to be correlated to hmF2. For this, we introduce a new ionospheric index, k, which ultimately relates electron density parameters and can be a very useful tool for describing the topside ionosphere shape. Our study is an initial one location, one season, 30-day study, and future work is needed to verify the robustness of our claim. Generally, the ionospheric profile shape, requires knowledge of several ionospheric parameters: electron, ion and neutral temperatures, ion composition, electric fields, and neutral winds, and is dependent upon seasons, local time, location, and the level of solar and geomagnetic activity; however, with this new index, only readily-available, ionospheric density information is needed. Such information, as used in this study, is obtained from a bottomside electron density profile provided by an ionosonde, and TEC data provided by a local, collocated GPS receiver.

  14. Radioresistance of experimentally-produced hybrid of Indian spinach (Beta palonga Basu and Mukherjee)

    International Nuclear Information System (INIS)

    Mukherjee, K.K.; Basu, R.K.

    1975-01-01

    An experimentally-produced hybrid between red and green plants of Beta palonga and the segregating population in F 2 showed more resistance to acute X-irradiation of seed than did their parents, as measured by seed germination, plant height, abnormal plant growth, chromosomal abnormality during meiosis and pollen grain sterility. In every measurement the F 2 plants were more sensitive than the F 1 hybrid. The radiosensitivity could not be interpreted in terms of average interphase chromosome volume. The resistance of the hybrid is suggested to be due to factors associated with heterozygosity and heterosis, although this has not been definately established. (author)

  15. Glass formation in RbF-BeF2-ErF3 system

    International Nuclear Information System (INIS)

    Reshetnikova, L.P.; Topshinoev, A.P.; Zakharova, B.S.; Sipachev, V.A.

    1987-01-01

    IR spectroscopic method (200-2000 cm -1 ) is used to study the glass structure in RbF-BeF 2 -ErF 3 system. It is shown that with increase of erbium fluoride content in fluoroberyllate glasses the absorption bands characteristic of (BeF 3 ) n n- groupings, appear in spectra. DTA and X-ray diffraction analysis of the glass annealing products are used to study the glass crystallization process. It is stated that erbium fluoride introduction into the glass results in increase of crystallization stability. The glass structure model is suggested

  16. Baryon axial charges and momentum fractions with N{sub f}=2+1 dynamical fermions

    Energy Technology Data Exchange (ETDEWEB)

    Goeckeler, M.; Haegler, P. [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Horsley, R. [Edinburgh Univ. (GB). School of Physics and Astronomy] (and others)

    2011-02-15

    We report on recent results of the QCDSF/UKQCD Collaboration on investigations of baryon structure using configurations generated with N{sub f}=2+1 dynamical flavours of O(a) improved Wilson fermions. With the strange quark mass as an additional dynamical degree of freedom in our simulations we avoid the need for a partially quenched approximation when investigating the properties of particles containing a strange quark, e.g. the hyperons. In particular, we focus on the nucleon and hyperon axial coupling constants and quark momentum fractions. (orig.)

  17. Measurement of the photon structure function F2 gamma with the L3 detector at LEP

    CERN Document Server

    Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Jin, B.N.; Jindal, P.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Mermod, P.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

    2005-01-01

    The e+e- -> e+e- hadrons reaction, where one of the two electrons is detected in a low polar-angle calorimeter, is analysed in order to measure the hadronic photon structure function F2gamma . The full high-energy and high-luminosity data set, collected with the L3 detector at centre-of-mass energies 189-209GeV, corresponding to an integrated luminosity of 608/pb is used. The Q^2 range 11-34GeV^2 and the x range 0.006-0.556 are considered. The data are compared with recent parton density functions.

  18. Laser excited fluorescence spectrum of Ho3+:SrF2 single crystal

    International Nuclear Information System (INIS)

    Lal, Bansi; Ramachandra Rao, D.

    1980-01-01

    The fluorescence spectrum of Ho 3+ : SrF 2 single crystal excited by the various lines of an Ar + laser, is reported. The three fluorescence groups recorded in the region 5300-7700 A, correspond to the transitions from ( 5 F 4 , 5 S 2 ) to 5 I 8 , 5 F 5 to 5 I 8 , 5 F 3 to 5 I 7 and ( 5 F 4 , 5 S 2 ) to 5 I 7 . Marked changes in the total integrated intensity of the various fluorescence groups with the change in the exciting wavelength are observed. (author)

  19. Dark matter search experiment with CaF2(Eu) scintillator at Kamioka Observatory

    International Nuclear Information System (INIS)

    Shimizu, Y.; Minowa, M.; Suganuma, W.; Inoue, Y.

    2006-01-01

    We report recent results of a WIMP dark matter search experiment using 310 g of CaF 2 (Eu) scintillator at Kamioka Observatory. We chose a highly radio-pure crystal, PMTs and radiation shields, so that the background rate decreased considerably. We derived limits on the spin dependent WIMP-proton and WIMP-neutron coupling coefficients, a p and a n . The limits excluded a part of the parameter space allowed by the annual modulation observation of the DAMA NaI experiment

  20. Measurement of the Low-x Behaviour of the Photon Structure Function $F2-\\gamma$

    CERN Document Server

    Abbiendi, G.; Ainsley, C.; Akesson, P.F.; Alexander, G.; Allison, John; Anderson, K.J.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Bailey, I.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Biebel, O.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Boeriu, O.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Cammin, J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Cooke, O.C.; Couchman, J.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanti, M.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Glenzinski, D.; Goldberg, J.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Harin-Dirac, M.; Hauke, A.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Hensel, C.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klein, K.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lawson, I.; Layter, J.G.; Leins, A.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; Lillich, J.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Oh, A.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Pooth, O.; Przybycien, M.; Quadt, A.; Rembser, C.; Rick, H.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sarkisyan, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schmitt, S.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Tarem, S.; Taylor, R.J.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trefzger, T.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Vannerem, P.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C.P.; Ward, D.R.; Ward, J.J.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

    2000-01-01

    The photon structure function F2-gamma(x,Q**2) has been measured using data taken by the OPAL detector at centre-of-mass energies of 91Gev, 183Gev and 189Gev, in Q**2 ranges of 1.5 to 30.0 GeV**2 (LEP1), and 7.0 to 30.0 GeV**2 (LEP2), probing lower values of x than ever before. Since previous OPAL analyses, new Monte Carlo models and new methods, such as multi-variable unfolding, have been introduced, reducing significantly the model dependent systematic errors in the measurement.

  1. Discovery of a magnetic field in the δ Scuti F2m star ρ Pup

    Science.gov (United States)

    Neiner, C.; Wade, G. A.; Sikora, J.

    2017-06-01

    ρ Pup is a δ Scuti F2 pulsator, known to host a main radial mode as well as non-radial pulsations, with chemical peculiarities typical of evolved Am stars. We present a high-precision spectropolarimetric observations of this star, obtained with ESPaDOnS at the Canada-France-Hawaii Telescope in the frame of the BRITE spectropolarimetric survey. A magnetic field is clearly detected in ρ Pup, with a longitudinal field strength below 1 G. This makes ρ Pup the second known magnetic δ Scuti discovered, after HD 188774, and a possible cool evolved counterpart of the recently discovered ultraweakly magnetic Am family.

  2. Modeling ionospheric foF2 by using empirical orthogonal function analysis

    Directory of Open Access Journals (Sweden)

    E. A

    2011-08-01

    Full Text Available A similar-parameters interpolation method and an empirical orthogonal function analysis are used to construct empirical models for the ionospheric foF2 by using the observational data from three ground-based ionosonde stations in Japan which are Wakkanai (Geographic 45.4° N, 141.7° E, Kokubunji (Geographic 35.7° N, 140.1° E and Yamagawa (Geographic 31.2° N, 130.6° E during the years of 1971–1987. The impact of different drivers towards ionospheric foF2 can be well indicated by choosing appropriate proxies. It is shown that the missing data of original foF2 can be optimal refilled using similar-parameters method. The characteristics of base functions and associated coefficients of EOF model are analyzed. The diurnal variation of base functions can reflect the essential nature of ionospheric foF2 while the coefficients represent the long-term alteration tendency. The 1st order EOF coefficient A1 can reflect the feature of the components with solar cycle variation. A1 also contains an evident semi-annual variation component as well as a relatively weak annual fluctuation component. Both of which are not so obvious as the solar cycle variation. The 2nd order coefficient A2 contains mainly annual variation components. The 3rd order coefficient A3 and 4th order coefficient A4 contain both annual and semi-annual variation components. The seasonal variation, solar rotation oscillation and the small-scale irregularities are also included in the 4th order coefficient A4. The amplitude range and developing tendency of all these coefficients depend on the level of solar activity and geomagnetic activity. The reliability and validity of EOF model are verified by comparison with observational data and with International Reference Ionosphere (IRI. The agreement between observations and EOF model is quite well, indicating that the EOF model can reflect the major changes and the temporal distribution characteristics of the mid-latitude ionosphere of the

  3. Proactive vs reactive failure recovery assessment in combined fog-to-cloud (F2C) systems

    OpenAIRE

    Souza, Vitor Barbosa Carlos de; Masip Bruin, Xavier; Marín Tordera, Eva; Ramirez Almonte, Wilson; Sánchez López, Sergio

    2017-01-01

    The increasing number of end user devices at the edge of the network, along with their ever increasing computing capacity, as well as the advances in Data Center technologies, paved the way for the generation of Internet of Things (IoT). Several IoT services have been deployed leveraging Cloud Computing and, more recently, Fog Computing. In order to enable efficient control of cloud and fog premises, Fog-to-Cloud (F2C) has been recently proposed as a distributed architecture for coordinated m...

  4. Genetic linkage mapping in an F2 perennial ryegrass population using DArT markers

    DEFF Research Database (Denmark)

    Tomaszewski, Céline; Byrne, Stephen; Foito, Alexandra

    2012-01-01

    Perennial ryegrass is the principal forage grass species used in temperate agriculture. In recent years, significant efforts have been made to develop molecular marker strategies to allow cost-effective characterization of a large number of loci simultaneously. One such strategy involves using DAr......T markers, and a DArT array has recently been developed for the Lolium-Festuca complex. In this study, we report the first use of the DArTFest array to generate a genetic linkage map based on 326 markers in a Lolium perenne F2 population, consisting of 325 genotypes. For proof of concept, the map was used...

  5. Pseudoscalar decay constants from N{sub f}=2+1+1 twisted mass lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Farchioni, Federico [Muenster Univ. (Germany). Inst. fuer Theoretische Physik; Herdoiza, Gregorio; Jansen, Karl; Nube, Andreas [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Petschlies, Marcus [Humboldt-Univ., Berlin (Germany). Inst. fuer Physik; Urbach, Carsten [Bonn Univ. (Germany). Helmholtz-Inst. fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics

    2010-12-15

    We present first results for the pseudoscalar decay constants f{sub K}, f{sub D} and f{sub D{sub S}} from lattice QCD with N{sub f} = 2 + 1 + 1 flavours of dynamical quarks. The lattice simulations have been performed by the European Twisted Mass collaboration (ETMC) using maximally twisted mass quarks. For the pseudoscalar decay constants we follow a mixed action approach by using so called Osterwalder-Seiler fermions in the valence sector for strange and charm quarks. The data for two values of the lattice spacing and several values of the up/down quark mass is analysed using chiral perturbation theory. (orig.)

  6. Monte Carlo simulations of a ferromagnetic-FeF2 system

    International Nuclear Information System (INIS)

    Billoni, Orlando V.; Tamarit, Francisco A.; Cannas, Sergio A.

    2006-01-01

    In this work, we perform Monte Carlo simulations to study the magnetization reversal mechanism in ferromagnetic thin films on FeF 2 . In particular, we emulate a bilayer AFM/FM structure, where the AFM interface corresponds to an uncompensated (100) plane. The magnetic moments are modeled by classical Heisenberg spin variables. Our analysis focus on the role of the exchange interaction J AF between the FM spins and the spins belonging to the AFM interface on the reversal mechanisms of the magnetization. By simulating hysteresis loops we study the effect of temperature on the bias field

  7. Evaluation of thin CaF2 (Eu) scintillator for detecting tritium

    International Nuclear Information System (INIS)

    Chiles, M.M.

    1986-10-01

    The primary objective of this project was to investigate the feasibility of using a CaF 2 (Eu) scintillator for detecting low-energy beta particles from tritium. A proof-of-principle detector was designed for flowing tritium-spiked nitrogen gas across the surface of a thin scintillator, which was optically coupled between two low-noise photomultiplier tubes. Electronics for operating the two photomultiplier tubes in coincidence eliminated most of the tube noise pulses and allowed detection of the small pulses from the low-energy tritium beta particles

  8. The effect of inhibition of prostaglandin F2 alpha synthesis on placental expulsion in the ewe.

    OpenAIRE

    Chassagne, M; Barnouin, J

    1993-01-01

    Five ewes were injected with two doses of a nonsteroidal anti-inflammatory drug (NSAI), lysine acetyl salicylate, at birth of their first lamb and one hour later, and five others were injected once only, at birth of their first lamb. A control group of six animals was constituted. The times needed for fetal expulsion and placental release were recorded. The peripheral plasma PgF2 alpha (as PGFM) levels were measured prepartum during the seven last days of gestation, at parturition, then 1 h, ...

  9. Unresolved issues in the analysis of F2-isoprostanes, F4-neuroprostanes, isofurans, neurofurans, and F2-dihomo-isoprostanes in body fluids and tissue using gas chromatography/negative-ion chemical-ionization mass spectrometry.

    Science.gov (United States)

    Yen, H-C; Wei, H-J; Lin, C-L

    2015-01-01

    F2-isoprostanes (F2-IsoPs) generated from arachidonic acid (AA) have been recognized as the most reliable marker of nonenzymatic lipid peroxidation in vivo. F2-IsoPs are initially produced in esterified form on phospholipids, and then released into body fluids in free form. The same mechanism can lead to generation of F4-neuroprostanes (F4-NPs) and F2-dihomo-IsoPs from docosahexaenoic acid (DHA) and adrenic acid, respectively. In addition, isofurans (IsoFs) and neurofurans (NFs) may be preferentially produced from AA and DHA, respectively, under high oxygen tension. The detection of F2-IsoPs using gas chromatography/negative-ion chemical-ionization mass spectrometry (GC/NICI-MS) has been widely employed, which is important for human body fluids containing low quantity of free-form F2-IsoPs. F4-NPs have also been detected using GC/NICI-MS, but multiple peaks need to be quantified. In this paper, we summarize the basic workflow of the GC/NICI-MS method for analyzing F2-IsoPs and F4-NPs, and various formats of assays conducted by different groups. We then discuss the feasibility of simultaneous analysis of IsoFs, NFs, and F2-dihomo-IsoPs with F2-IsoPs or F4-NPs. Representative GC chromatograms for analyzing these markers in human body fluids and rat brain tissue are demonstrated. Furthermore, we discuss several factors that may affect the performance of the analysis, such as those related to the sample processing steps, interference from specimens, types of GC liners used, and the addition of electron multiplier voltage in the method setting for the MS detector. Finally, we question the appropriateness of measuring total (free plus esterified) levels of these markers in body fluids.

  10. Continuously tunable cw lasing near 2.75 μm in diode-pumped Er3+ : SrF2 and Er3+ : CaF2 crystals

    International Nuclear Information System (INIS)

    Basiev, Tasoltan T; Orlovskii, Yu V; Polyachenkova, M V; Fedorov, Pavel P; Kuznetsov, S V; Konyushkin, V A; Osiko, Vyacheslav V; Alimov, Olimkhon K; Dergachev, Alexey Yu

    2006-01-01

    CW lasing is obtained in Er 3+ (5%) : CaF 2 and Er 3+ (5%) : SrF 2 crystals near 2.75 μm with 0.4 and 2 W of output powers, respectively, upon transverse diode laser pumping into the upper 4 I 11/2 laser level of erbium ions at 980 nm. Continuous tuning of the laser wavelength between 2720 and 2760 nm is realised in the Er 3+ : SrF 2 crystal. (special issue devoted to the 90th anniversary of a.m. prokhorov)

  11. Genetic incompatibility dampens hybrid fertility more than hybrid viability: yeast as a case study.

    Directory of Open Access Journals (Sweden)

    Meibo Xu

    Full Text Available Genetic incompatibility is believed to be the major cause of postzygotic reproductive isolation. Despite huge efforts seeking for speciation-related incompatibilities in the past several decades, a general understanding of how genetic incompatibility evolves in affecting hybrid fitness is not available, primarily due to the fact that the number of known incompatibilities is small. Instead of further mapping specific incompatible genes, in this paper we aimed to know the overall effects of incompatibility on fertility and viability, the two aspects of fitness, by examining 89 gametes produced by yeast S. cerevisiae-S. paradoxus F1 hybrids. Homozygous F2 hybrids formed by autodiploidization of F1 gametes were subject to tests for growth rate and sporulation efficiency. We observed much stronger defects in sporulation than in clonal growth for every single F2 hybrid strain, indicating that genetic incompatibility affects hybrid fertility more than hybrid viability in yeast. We related this finding in part to the fast-evolving nature of meiosis-related genes, and proposed that the generally low expression levels of these genes might be a cause of the observation.

  12. Influenza virus PB1-F2 protein induces cell death through mitochondrial ANT3 and VDAC1.

    Directory of Open Access Journals (Sweden)

    Dmitriy Zamarin

    2005-09-01

    Full Text Available The influenza virus PB1-F2 is an 87-amino acid mitochondrial protein that previously has been shown to induce cell death, although the mechanism of apoptosis induction has remained unclear. In the process of characterizing its mechanism of action we found that the viral PB1-F2 protein sensitizes cells to apoptotic stimuli such as tumor necrosis factor alpha, as demonstrated by increased cleavage of caspase 3 substrates in PB1-F2-expressing cells. Moreover, treatment of purified mouse liver mitochondria with recombinant PB1-F2 protein resulted in cytochrome c release, loss of the mitochondrial membrane potential, and enhancement of tBid-induced mitochondrial permeabilization, suggesting a possible mechanism for the observed cellular sensitization to apoptosis. Using glutathione-S-transferase pulldowns with subsequent mass spectrometric analysis, we identified the mitochondrial interactors of the PB1-F2 protein and showed that the viral protein uniquely interacts with the inner mitochondrial membrane adenine nucleotide translocator 3 and the outer mitochondrial membrane voltage-dependent anion channel 1, both of which are implicated in the mitochondrial permeability transition during apoptosis. Consistent with this interaction, blockers of the permeability transition pore complex (PTPC inhibited PB1-F2-induced mitochondrial permeabilization. Based on our findings, we propose a model whereby the proapoptotic PB1-F2 protein acts through the mitochondrial PTPC and may play a role in the down-regulation of the host immune response to infection.

  13. The fabrication of ordered arrays of exchange biased Ni/FeF2 nanostructures

    International Nuclear Information System (INIS)

    Kovylina, M; Labarta, A; Batlle, X; Erekhinsky, M; Schuller, I K; Morales, R

    2010-01-01

    The fabrication of ordered arrays of exchange biased Ni/FeF 2 nanostructures by focused ion beam lithography is reported. High quality nano-elements, with controlled removal depth and no significant re-deposition, were carved using small ion beam currents (30 pA), moderate dwell times (1 μs) and repeated passages over the same area. Two types of nanostructures were fabricated: square arrays of circular dots with diameters from 125 ± 8 to 500 ± 12 nm and periodicities ranging from 200 ± 8 to 1000 ± 12 nm, and square arrays of square antidots (207 ± 8 nm in edge length) with periodicities ranging from 300 ± 8 to 1200 ± 12 nm. The arrays were characterized using scanning ion and electron microscopy, and atomic force microscopy. The effect of the patterning on the exchange bias field (i.e., the shift in the hysteresis loop of ferromagnetic Ni due to proximity to antiferromagnetic FeF 2 ) was studied using magneto-transport measurements. These high quality nanostructures offer a unique method to address some of the open questions regarding the microscopic origin of exchange bias. This is not only of major relevance in the fabrication and miniaturization of magnetic devices but it is also one of the important proximity phenomena in nanoscience and materials science.

  14. Adsorption effect in non-reaction wetting: In-Ti on CaF2

    International Nuclear Information System (INIS)

    Glickman, E.; Fuks, D.; Frage, N.; Barzilai, S.; Froumin, N.

    2012-01-01

    The experiments show that the alloying liquid In with only (0.1-0.5) at% Ti dramatically reduces the equilibrium contact angle Θ ∞ formed by In on the surface of CaF 2 . The aim of this paper is to clarify whether this practically important and conceptually challenging effect can be explained solely by Ti adsorption at the F-terminated solid-liquid interface without resorting to any other Ti-induced effect. The combination of ab initio calculations and regular solution approximation was proposed for finding the binding energy, ΔE Ti of Ti adatom with the interface ''CaF 2 /liquid solutions In-Ti.'' With thus obtained ΔE Ti =1.16 eV, we calculated from the Shishkovsky isotherm the reduction in the solid-liquid interface energy, Δγ SL induced by Ti adsorption from liquid In with various Ti concentration, C. It was found that Δγ SL (C) dependence demonstrated close inverse correspondence with Θ ∞ (C) and that the theory fitted very well all available experimental data on the concentration and temperature dependence of Δγ SL . It was concluded that the Ti adsorption effect is large enough to account for the observed wetting improvement. The proposed multiscale modeling approach to the role of adsorption in wetting can be applied also to other nonreactive systems ''liquid metal-ceramics'' where the substrate determines the surface density of the adsorption sites for the active element. (orig.)

  15. Influence of substrate temperature on properties of MgF2 coatings

    International Nuclear Information System (INIS)

    Yu Hua; Qi Hongji; Cui Yun; Shen Yanming; Shao Jianda; Fan Zhengxiu

    2007-01-01

    Thermal boat evaporation was employed to prepare MgF 2 single-layer coatings upon both JGS1 and UBK7 substrates at different substrate temperatures. Microstructure, transmittance and residual stress of these coatings were measured by X-ray diffraction, spectrophotometer, and optical interferometer, respectively. Measurement of laser induced damage threshold (LIDT) of the samples was performed at 355 nm, 8 ns pulses. The results showed that high substrate temperature was beneficial to crystallization of the film. Above 244 deg. C, the refractive index increased gradually with the substrate temperature rising. Whereas, it was exceptional at 210 deg. C that the refractive index was higher than those deposited at 244 and 277 deg. C. The tensile residual stresses were exhibited in all MgF 2 films, but not well correlated with the substrate temperature. In addition, the stresses were comparatively smaller upon JGS1 substrates. A tendency could be seen that the LIDTs reached the highest values at about 244 deg. C, and the films upon JGS1 had higher LIDTs than those upon UBK7 substrates at the same temperature. Meanwhile, the damage morphologies showed that the laser damage of the coating resulted from an absorbing center at the film-substrate interface. The features of the damages were displayed by an absorbing center dominated model. Furthermore, the reason of the difference in LIDT values was discussed in detail

  16. F2-isoprostanes and F4-neuroprostanes as markers of intracranial aneurysm development.

    Science.gov (United States)

    Syta-Krzyżanowska, Anna; Jarocka-Karpowicz, Iwona; Kochanowicz, Jan; Turek, Grzegorz; Rutkowski, Robert; Gorbacz, Krzysztof; Mariak, Zenon; Skrzydlewska, Elżbieta

    2018-04-24

    Intracranial aneurysms are common, occurring in about 1-2% of the population. Saccular aneurysm is a pouch-like pathological dilatation of an intracranial artery that develops when the cerebral artery wall becomes too weak to resist hemodynamic pressure and distends. The aim of this study was to determine whether the development of intracranial aneurysms and subarachnoid hemorrhage (SAH) affects neuronal phospholipid metabolism, and what influence different invasive treatments have on brain free radical phospholipid metabolism. The level of polyunsaturated fatty acid (PUFA) cyclization products - F2-isoprostanes and F4-neuroprostanes - was examined using liquid chromatography - mass spectrometry (LC-MS) in the plasma of patients with brain aneurysm and resulting subarachnoid hemorrhage. It was revealed that an aneurysm leads to the enhancement of lipid peroxidation with a significant increase in plasma F2-isoprostanes and F4-neuroprostanes (more than 3-fold and 11-fold, respectively) in comparison to healthy subjects. The rupture of an aneurysm results in hemorrhage and an additional increase in examined prostaglandin derivatives. The embolization and clipping of aneurysms contribute to a gradual restoration of metabolic homeostasis in brain cells, which is visible in the decrease in PUFA cyclization products. The results indicate that aneurysm development is associated with enhanced inflammation and oxidative stress, factors which favor lipid peroxidation, particularly in neurons, whose membranes are rich in docosahexaenoic acid, a precursor of F4-neuroprostanes.

  17. Long-term trends of foF2 independent of geomagnetic activity

    Directory of Open Access Journals (Sweden)

    A. D. Danilov

    Full Text Available A detailed analysis of the foF2 data at a series of ionospheric stations is performed to reveal long-term trends independent of the long-term changes in geomagnetic activity during the recent decades (nongeomagnetic trends. The method developed by the author and published earlier is used. It is found that the results for 21 out of 23 stations considered agree well and give a relative nongeomagnetic trend of -0.0012 per year (or an absolute nongeomagnetic trend of about -0.012 MHz per year for the period between 1958 and the mid-nineties. The trends derived show no dependence on geomagnetic latitude or local time, a fact confirming their independence of geomagnetic activity. The consideration of the earlier period (1948–1985 for a few stations for which the corresponding data are available provides significantly lower foF2 trends, the difference between the later and earlier periods being a factor of 1.6. This is a strong argument in favor of an anthropogenic nature of the trends derived.Key words. Ionosphere (ionosphere-atmosphere interactions; ionospheric disturbances; mid-latitude ionosphere

  18. Size distribution of BaF2 nanocrystallites in transparent glass ceramics

    International Nuclear Information System (INIS)

    Bocker, Christian; Bhattacharyya, Somnath; Hoeche, Thomas; Ruessel, Christian

    2009-01-01

    In glasses with the composition 1.9 Na 2 O-15 K 2 O-7.5 Al 2 O 3 -69.6 SiO 2 -6 BaF 2 (in mol.%), BaF 2 nanocrystalline precipitates are formed upon heat treatment. Using dark-field and bright-field transmission electron micrographs, crystallite size distributions are obtained for samples crystallized at various temperatures. According to the 'tomato-salad problem', the size distributions are corrected and then compared to various theories of grain growth taking into account coarsening of the crystallites during heat treatment. The experimental crystallite size distributions show for smaller mean crystallite sizes a more symmetric shape in comparison to the theories of Lifshitz-Slyozov-Wagner (LSW) or Brailsford and Wynblatt (B and W). With increasing mean crystallite sizes to about 18 nm at higher heat-treatment temperatures, the full width at half maximum of the observed distributions decreases and becomes even narrower than the LSW function. These findings indicate that in the investigated nano glass ceramics no coarsening by Ostwald ripening or coalescence occurs. This is explained by the formation of a diffusion barrier around each nanocrystallite which limits the size of the crystallites and hence results in such a narrow and uniform crystallite size distribution.

  19. Chiral phase transition of QCD with N{sub f}=2+1 flavors from holography

    Energy Technology Data Exchange (ETDEWEB)

    Li, Danning [Department of Physics, Jinan University,Guangzhou 510632 (China); Huang, Mei [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China); University of Chinese Academy of Sciences,Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,Beijing 100049 (China)

    2017-02-08

    Chiral phase transition for three-flavor N{sub f}=2+1 QCD with m{sub u}=m{sub d}≠m{sub s} is investigated in a modified soft-wall holographic QCD model. Solving temperature dependent chiral condensates from equations of motion of the modified soft-wall model, we extract the quark mass dependence of the order of chiral phase transition in the case of N{sub f}=2+1, and the result is in agreement with the “Columbia Plot”, which is summarized from lattice simulations and other non-perturbative methods. First order phase transition is observed around the three flavor chiral limit m{sub u/d}=0,m{sub s}=0, while at sufficient large quark masses it turns to be a crossover phase transition. The first order and crossover regions are separated by a second order phase transition line. The second order line is divided into two parts by the m{sub u/d}=m{sub s} line, and the m{sub s} dependence of the transition temperature in these two parts are totally contrast, which might indicate that the two parts are governed by different universality classes.

  20. A Study on molecular characterization of Razi Bacillus anthracis Sterne 34F2 substrain in Iran

    Directory of Open Access Journals (Sweden)

    Tadayon, K.

    2016-07-01

    Full Text Available Anthrax, a zoonotic disease caused by Bacillus anthracis, has affected humans since ancient times. For genomic characterization of Razi B. anthracis Sterne 34F2 substrain, single nucleotide polymorphism (SNP genotyping method developed by Van Erth, variable-number tandem-repeat (VNTR-8 analysis proposed by Keim, and multiple-locus VNTR analysis (MLVA-3 introduced by Levy were employed. In the SNPs typing system, where the nucleotide content of the genome at 13 evolutionary canonical loci was collectively analyzed, the originally South African 34F2 substrain was categorized in the A.Br.001/002 subgroup. In the VNTR-8 analysis, fragments with lengths of 314, 229, 162, 580, 532, 158, and 137 bp were identified at the following loci: vrrA, vrrB1, vrrB2, vrrC1, vrrC2, CG3, and pxO1, respectively. In addition, application of Levy's MLVA-3 genotyping method revealed that the genome of this strain carried 941, 451, and 864 bp fragments at AA03, AJ03, and AA07 loci, respectively. The present findings are undoubtedly helpful in meeting the requirements set by the World Organization for Animal Health (OIE and World Health Organization (WHO for anthrax vaccine manufacturers including Razi Institute. However, further similar studies are required to promote the current epidemiological knowledge of anthrax in Iran.

  1. Thermal performance study of a box type solar cooker: evaluation of second figure of merit, F2

    International Nuclear Information System (INIS)

    Subudh Kumar

    2006-01-01

    The thermal performance of a box type solar cooker can be evaluated through the determination of two figures of merit-F 1 and F 2 . The F 1 is defined as the ratio of optical efficiency factor (η o ) the overall heat loss coefficient (U L ) and F 2 relates to the effectiveness of heat exchange between cooker interiors and contents of the pots. The values of F 1 and F 2 can be found experimentally from the stagnation (no-load) and load (water) tests respectively. The sensible heating curve (a plot between pot water temperature and time) from the load test is used for determination of F 2 . An accurate determination of F 2 is necessary for making the correct and reliable assessment of solar cooker performance. In the present work, the thermal analysis has been carried out to simulate the sensible heating curves for different loads of water in the commercially available, fibre body double-glazed box type solar cooker (size 0.245 m 2 ) by using the heat balance equation. The comparison between the simulated and experimental sensible heating curves is presented. The close agreement in the results shows that the simulated heating curve can be employed for predicting the thermal performance (or F 2 ) of the solar cooker. The F 2 for different loads of water in the solar cooker have been obtained using the computer simulation, while considering the variable overall heat loss coefficient U L (a function of pot water temperature). The results indicate that F 2 increases linearly up to a load of 1.5 kg. Thereafter, the increase in the value of F 2 decreases gradually with the load

  2. Correlation studies for B-spline modeled F2 Chapman parameters obtained from FORMOSAT-3/COSMIC data

    Directory of Open Access Journals (Sweden)

    M. Limberger

    2014-12-01

    Full Text Available The determination of ionospheric key quantities such as the maximum electron density of the F2 layer NmF2, the corresponding F2 peak height hmF2 and the F2 scale height HF2 are of high relevance in 4-D ionosphere modeling to provide information on the vertical structure of the electron density (Ne. The Ne distribution with respect to height can, for instance, be modeled by the commonly accepted F2 Chapman layer. An adequate and observation driven description of the vertical Ne variation can be obtained from electron density profiles (EDPs derived by ionospheric radio occultation measurements between GPS and low Earth orbiter (LEO satellites. For these purposes, the six FORMOSAT-3/COSMIC (F3/C satellites provide an excellent opportunity to collect EDPs that cover most of the ionospheric region, in particular the F2 layer. For the contents of this paper, F3/C EDPs have been exploited to determine NmF2, hmF2 and HF2 within a regional modeling approach. As mathematical base functions, endpoint-interpolating polynomial B-splines are considered to model the key parameters with respect to longitude, latitude and time. The description of deterministic processes and the verification of this modeling approach have been published previously in Limberger et al. (2013, whereas this paper should be considered as an extension dealing with related correlation studies, a topic to which less attention has been paid in the literature. Relations between the B-spline series coefficients regarding specific key parameters as well as dependencies between the three F2 Chapman key parameters are in the main focus. Dependencies are interpreted from the post-derived correlation matrices as a result of (1 a simulated scenario without data gaps by taking dense, homogenously distributed profiles into account and (2 two real data scenarios on 1 July 2008 and 1 July 2012 including sparsely, inhomogeneously distributed F3/C EDPs. Moderate correlations between hmF2 and HF2 as

  3. Transcriptomic analysis of host immune and cell death responses associated with the influenza A virus PB1-F2 protein.

    Directory of Open Access Journals (Sweden)

    Ronan Le Goffic

    2011-08-01

    Full Text Available Airway inflammation plays a major role in the pathogenesis of influenza viruses and can lead to a fatal outcome. One of the challenging objectives in the field of influenza research is the identification of the molecular bases associated to the immunopathological disorders developed during infection. While its precise function in the virus cycle is still unclear, the viral protein PB1-F2 is proposed to exert a deleterious activity within the infected host. Using an engineered recombinant virus unable to express PB1-F2 and its wild-type homolog, we analyzed and compared the pathogenicity and host response developed by the two viruses in a mouse model. We confirmed that the deletion of PB1-F2 renders the virus less virulent. The global transcriptomic analyses of the infected lungs revealed a potent impact of PB1-F2 on the response developed by the host. Thus, after two days post-infection, PB1-F2 invalidation severely decreased the number of genes activated by the host. PB1-F2 expression induced an increase in the number and level of expression of activated genes linked to cell death, inflammatory response and neutrophil chemotaxis. When generating interactive gene networks specific to PB1-F2, we identified IFN-γ as a central regulator of PB1-F2-regulated genes. The enhanced cell death of airway-recruited leukocytes was evidenced using an apoptosis assay, confirming the pro-apoptotic properties of PB1-F2. Using a NF-kB luciferase adenoviral vector, we were able to quantify in vivo the implication of NF-kB in the inflammation mediated by the influenza virus infection; we found that PB1-F2 expression intensifies the NF-kB activity. Finally, we quantified the neutrophil recruitment within the airways, and showed that this type of leukocyte is more abundant during the infection of the wild-type virus. Collectively, these data demonstrate that PB1-F2 strongly influences the early host response during IAV infection and provides new insights into the

  4. Measurement of the proton structure function F2 at low χand low Q2 at HERA

    International Nuclear Information System (INIS)

    Derrick, M.; Krakauer, D.; Magill, S.

    1995-10-01

    We report on a measurement of the proton structure function F 2 in the range 3.5x10 -5 ≤x≤4x10 -3 and 1.5 GeV 2 ≤Q 2 ≤15 GeV 2 at the ep collider HERA operating at a centre-of-mass energy of √s=300 GeV. The rise of F 2 with decreasing x observed in the previous HERA measurements persists in this lower x and Q 2 range. The Q 2 evolution of F 2 , even at the lowest Q 2 and x measured, is consistent with perturbative QCD. (orig.)

  5. Measurement of F_2^{c\\bar{c}} and F_2^{b\\bar{b}} at Low Q^2 and x using the H1 Vertex Detector at HERA

    CERN Document Server

    Aktas, A.; Anthonis, T.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Bahr, J.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, Ch.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Brown, D.P.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Caron, S.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; de Boer, Y.; Delcourt, B.; De Roeck, A.; Desch, K.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Ellerbrock, M.; Erdmann, W.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Finke, L.; Fleischer, M.; Fleischmann, P.; Fleming, Y.H.; Flucke, G.; Fomenko, A.; Foresti, I.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Goyon, C.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B.R.; Grindhammer, Guenter; Gwilliam, C.; Haidt, D.; Hajduk, L.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Henshaw, O.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Keller, N.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Kuckens, J.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Luke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxeld, S.J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Portheault, B.; Povh, B.; Prideaux, P.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauvan, E.; Schatzel, S.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sedlak, K.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Stella, B.; Stiewe, J.; Strauch, I.; Straumann, U.; Tchoulakov, V.; Thompson, Graham; Thompson, P.D.; Tomasz, F.; Traynor, D.; Truoel, Peter; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, Marcel; Usik, A.; Utkin, D.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vest, A.; Vinokurova, S.; Volchinski, V.; Vujicic, B.; Wacker, K.; Wagner, J.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Werner, N.; Wessels, M.; Wessling, B.; Wigmore, C.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2006-01-01

    Measurements are presented of inclusive charm and beauty cross sections in e^+p collisions at HERA for values of photon virtuality 12 \\le Q^2 \\le 60 GeV^2 and of the Bjorken scaling variable 0.0002 \\le x \\le 0.005. The fractions of events containing charm and beauty quarks are determined using a method based on the impact parameter, in the transverse plane, of tracks to the primary vertex, as measured by the H1 vertex detector. Values for the structure functions F_2^{c\\bar{c}} and F_2^{b\\bar{b}} are obtained. This is the first measurement of F_2^{b\\bar{b}} in this kinematic range. The results are found to be compatible with the predictions of perturbative quantum chromodynamics and withprevious measurements of F_2^{c\\bar{c}}.

  6. Small-x behavior of the structure function F2 and its slope ∂lnF2/∂ln(1/x) for ''frozen'' and analytic strong-coupling constants

    International Nuclear Information System (INIS)

    Cvetic, G.; Kniehl, B.A.; Kotikov, A.V.

    2009-06-01

    Using the leading-twist approximation of the Wilson operator product expansion with ''frozen'' and analytic versions of the strong-coupling constant, we show that the Bessel-inspired behavior of the structure function F 2 and its slope ∂lnF 2 /∂ln(1/x) at small values of x, obtained for a at initial condition in the DGLAP evolution equations, leads to good agreement with experimental data of deep-inelastic scattering at DESY HERA. (orig.)

  7. Hybrid vigour and gene action for two quantitative traits of castor ...

    African Journals Online (AJOL)

    Five homozygous lines of castor plant, namely RS1-Om, RN1-Om, RTl-2m, RSl- Owm, and RNl- Omb, were crossed to raise F1, F2, BC1, and BC2 generations. The hybrids were tested for hybrid vigour for two metric traits, viz; number of pods per plant and seed yield per plant. Highly significant hybrid vigour was detected ...

  8. Hybrid reactors

    International Nuclear Information System (INIS)

    Moir, R.W.

    1980-01-01

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of 233 U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m -2 , and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid

  9. Scintillation response of BaF2 and YAlO3:Ce (YAP:Ce) to energetic ions

    International Nuclear Information System (INIS)

    Slunga, E.; Cederwall, B.; Ideguchi, E.; Kerek, A.; Klamra, W.; Marel, J. van der; Novak, D.; Norlin, L.-O.

    2001-01-01

    The scintillation response of BaF 2 and YAP:Ce to protons, α particles, 16 O and 28 Si ions in the 5-30 MeV range has been investigated. The ratio between the fast and slow parts of the scintillator signal for BaF 2 has been used to separate protons, α particles and heavier ions, and the dependence of this ratio on the particle energy has been studied. The time constants and intensities of the two components of the YAP:Ce signal were measured, as were the time constant and intensity of the weak component of the slow part of the BaF 2 signal. Furthermore, the dependence of the light yield on the particle energy has been investigated for both BaF 2 and YAP:Ce

  10. Simulation and analysis of Au-MgF2 structure in plasmonic sensor in near infrared spectral region

    Science.gov (United States)

    Sharma, Anuj K.

    2018-05-01

    Plasmonic sensor based on metal-dielectric combination of gold and MgF2 layers is studied in near infrared (NIR) spectral region. An emphasis is given on the effect of variable thickness of MgF2 layer in combination with operating wavelength and gold layer thickness on the sensor's performance in NIR. It is established that the variation in MgF2 thickness in connection with plasmon penetration depth leads to significant variation in sensor's performance. The analysis leads to a conclusion that taking smaller values of MgF2 layer thickness and operating at longer NIR wavelength leads to enhanced sensing performance. Also, fluoride glass can provide better sensing performance than chalcogenide glass and silicon substrate.

  11. Coevaporation of Y, BaF2, and Cu utilizing a quadrupole mass spectrometer as a rate measuring probe

    International Nuclear Information System (INIS)

    Hudner, J.; Oestling, M.; Ohlsen, H.; Stolt, L.

    1991-01-01

    An ultrahigh vacuum coevaporator equipped with three sources for preparation of Y--BaF 2 --Cu--O thin films is described. Evaporation rates of Y, BaF 2 , and Cu were controlled using a quadrupole mass spectrometer operating in a multiplexed mode. To evaluate the method depositions have been performed using different source configurations and evaporation rates. Utilizing Rutherford backscattering spectrometry absolute values of the actual evaporation rates were determined. It was observed that the mass-spectrometer sensitivity is highest for Y, followed by BaF 2 (BaF + is the measured ion) and Cu. A partial pressure of oxygen during evaporation of Y, BaF 2 , and Cu affected mainly the rate of Y. It is shown that the mass spectrometer can be utilized to precisely control the film composition

  12. Matrix infrared spectra and electronic structure calculations of the first actinide borylene: FB=ThF(2).

    Science.gov (United States)

    Wang, Xuefeng; Roos, Björn O; Andrews, Lester

    2010-03-14

    Laser-ablated Th atoms react with BF(3) during condensation in excess argon at 6 K to form the first actinide borylene (FB=ThF(2)) and actinide-boron multiple bond. Three new product absorptions in the B-F and Th-F stretching regions of matrix infrared spectra are assigned to FB=ThF(2) from comparison to theoretically predicted vibrational frequencies.

  13. Causes of the mid-latitudinal daytime NmF2 semi-annual anomaly at solar minimum

    Science.gov (United States)

    Pavlov, A. V.

    2018-04-01

    Ionospheric ionosonde and radar observations and theoretical calculations of the F2-layer peak altitude, hmF2, and number density, NmF2, over Millstone Hill during winter, spring, summer, and autumn geomagnetically quiet time periods at low solar activity are used to study the causes of the observed daytime NmF2 semi-annual anomaly. It follows from the model simulations that this anomalous phenomenon arises in the ionosphere mainly as a result of seasonal variations of the following atmospheric parameters: (1) the plasma drift along geomagnetic field lines due to corresponding changes in neutral wind components, (2) temperature and number densities of the neutral atmosphere, and (3) an optical thickness of the atmosphere caused by the dependence of the solar zenith angle on the day of the year for the same solar local time. Seasonal variations of the production rate unexcited O+ ions due to chemical reactions involving electronically excited O+ ions contribute to the formation of the NmF2 semi-annual anomaly during the predominant part of the existence time of this anomalous phenomenon. However, these seasonal variations are not significant, and this mechanism should be considered only as an additional source of the NmF2 semi-annual anomaly during its time of existence. The reactions of unexcited O+ ions with vibrationally excited N2 and O2 cause only weak changes of NmF2 and these changes are close in magnitude at a given solar local time during the winter, spring, summer, and autumn daytime conditions under consideration. Ignoring these reactions cannot produce a significant impact on the formation of the NmF2 semi-annual anomaly.

  14. Development and properties of duplex MgF2/PCL coatings on biodegradable magnesium alloy for biomedical applications.

    Science.gov (United States)

    Makkar, Preeti; Kang, Hoe Jin; Padalhin, Andrew R; Park, Ihho; Moon, Byoung-Gi; Lee, Byong Taek

    2018-01-01

    The present work addresses the performance of polycaprolactone (PCL) coating on fluoride treated (MgF2) biodegradable ZK60 magnesium alloy (Mg) for biomedical application. MgF2 conversion layer was first produced by immersing Mg alloy substrate in hydrofluoric acid solution. The outer PCL coating was then prepared using dip coating technique. Morphology, elements profile, phase structure, roughness, mechanical properties, invitro corrosion, and biocompatibility of duplex MgF2/PCL coating were then characterized and compared to those of fluoride coated and uncoated Mg samples. The invivo degradation behavior and biocompatibility of duplex MgF2/PCL coating with respect to ZK60 Mg alloy were also studied using rabbit model for 2 weeks. SEM and TEM analysis showed that the duplex coating was uniform and comprised of porous PCL film (~3.3 μm) as upper layer with compact MgF2 (~2.2 μm) as inner layer. No significant change in microhardness was found on duplex coating compared with uncoated ZK60 Mg alloy. The duplex coating showed improved invitro corrosion resistance than single layered MgF2 or uncoated alloy samples. The duplex coating also resulted in better cell viability, cell adhesion, and cell proliferation compared to fluoride coated or uncoated alloy. Preliminary invivo studies indicated that duplex MgF2/PCL coating reduced the degradation rate of ZK60 Mg alloy and exhibited good biocompatibility. These results suggested that duplex MgF2/PCL coating on magnesium alloy might have great potential for orthopedic applications.

  15. Study of the fluorescence blinking behavior of single F2 color centers in LiF crystal

    International Nuclear Information System (INIS)

    Boichenko, S V; Koenig, K; Zilov, S A; Dresvianskiy, V P; Rakevich, A L; Kuznetsov, A V; Bartul, A V; Martynovich, E F; Voitovich, A P

    2014-01-01

    Using confocal fluorescence microscopy technique, we observed experimentally the luminescence of single F 2 color centers in LiF crystal. It is disclosed that the fluorescence shows blinking behavior. It is shown that this phenomenon is caused by the F 2 center reorientation occurring during the experiment. The ratio of luminescence intensities of differently oriented centers is assessed theoretically for two different experiment configurations. The calculated ratios are in fine agreement with experimental result

  16. The properties of CaF2:Dy used as a thermoluminescent dosimeter at low doses

    International Nuclear Information System (INIS)

    Budd, T.

    1976-05-01

    Chips of CaF 2 :Dy have been studied to assess their usefulness as a thermoluminescent dosimeter for the measurement of doses of the order of 1 mrad in water. The glow curve structure and the total light output from peaks below about 240 0 C have both been studied. Experiments have been done to study linearity, fading and energy dependence. Fading was found to be 15% in the first day and a further 21% over four weeks. The response of the material per rad in water showed a peak at 30 keV where the sensitivity was 17.5 times the value at 1 MeV. Doses of 0.1 mrad have been assessed with a standard deviation of 25%. (author)

  17. The immune response of adult opossums (Didelphis virginiana) to the bacteriophage f2

    Science.gov (United States)

    Rowlands, D. T.

    1970-01-01

    Humoral immunity to the bacteriophage f2 was studied in adult opossums (Didelphis virginiana) and their responses were compared to those in New Zealand White rabbits. Antibodies were found in the serum of opossums 7 days after the subcutaneous injection of the antigen and peak antibody responses were observed between 10 and 21 days after immunization. A second injection of antigen resulted in increased antibody activity. In either case the level of serum antibody reached in opossums was less than that in rabbits. More striking, however, was the relatively slow conversion from γM to γG antibodies in opossums. The course of the immune response in adult opossums was more nearly like that of cold-blooded vertebrates than that of eutherian mammals. PMID:5416636

  18. Ab initio modeling of Al adsorption on CaF2 surfaces

    International Nuclear Information System (INIS)

    Barzilai, S.; Argaman, N.; Froumin, N.; Fuks, D.; Frage, N.

    2008-01-01

    Ab initio simulations of the adsorption of Al atoms on CaF 2 (0 0 1) and (1 1 1) surfaces have been performed for supercells with 7 different atomic configurations, using density functional theory. For (1 1 1) surfaces, a repulsive interaction was observed for most configurations, while a weak attraction was obtained when the Al atom was placed above F atoms. For the Ca-terminated (0 0 1) surface, the adsorption energy was about 5 times larger, whereas for the F-terminated (0 0 1) surface it was about 20 times greater. The comparative analysis indicates that the (0 0 1) surfaces are reactive and have a strong Al adatom bonding (chemisorption), especially for the F-terminated substrate. On the contrary, the (1 1 1) plane may be considered as non-reactive (physisorption), having a weak bonding of the Al adatom above the F site

  19. Internal background build-up measurements in CaF2:Mn thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Balasybrahmanyam, V.; Measures, M.P.

    1977-01-01

    Some problems associated with the internal background build-up (IBB) of CaF 2 :Mn thermoluminescent dosimeters are reported. As a result of an investigation of batches of the EG and G model 15 dosimeter it is considered that measurements using this type of dosimeter are accurate and reproducible once the IBB has been determined. However, the use of the Manufacturer's claimed average of 0.064 mR/day can lead to erroneous results when determining environmental background dose rates. The authors therefore urge a rigid quality control program by the manufacturer and suggest that purchasers should be supplied with IBB information of each batch of dosimeters. Meanwhile each user should be aware of the IBB problem and be extremely cautious when using these dosimeters for environmental monitoring purposes. (U.K.)

  20. Genomic prediction based on next generation sequencing of 1000 F2-families in Lolium perenne L

    DEFF Research Database (Denmark)

    Fé, Dario; Ashraf, Bilal; Greve-Pedersen, Morten

    2014-01-01

    and abiotic stresses. The study is performed on 995 F2 families originated from the DLF breeding program. All families were genotyped by reduced representation sequencing. A total of 1,020,065 SNPs were detected and used for genomic prediction. First analyses, used for model testing, have been carried out...... on salt stress tolerance. Ryegrass families where sown in rockwool blocks (in four replicates) in greenhouse, and allowed to establish over 60 days using standard fertilization and watering. Three consecutive treatments, with increasing salt (NaCl) concentrations, were applied. Ten days after initiation...... of each treatment, the percentage of green matter was evaluated by visual scoring and by digital imaging. Preliminary analysis using GBLUP have identified a significant amount of genetic variance (individual heritabilities ranging between 0.20 and 0.40 and family heritabilities up to about 0.15). Genomic...

  1. Thermoluminescence dosimetry properties of new Cu doped CaF(2) nanoparticles.

    Science.gov (United States)

    Zahedifar, M; Sadeghi, E

    2013-12-01

    Nanoparticles of Cu-doped calcium fluoride were synthesised by using the hydrothermal method. The structure of the prepared nanomaterial was characterised by the X-ray diffraction (XRD) pattern and energy dispersive spectrometer. The particle size of 36 nm was calculated from the XRD data. Its shape and size were also observed by scanning electron microscope. Thermoluminescence (TL) and photoluminescence of the produced phosphor were also considered. The computerised glow curve deconvolution procedure was used to identify the number of glow peaks included in the TL glow curve of the CaF2:Cu nanoparticles. The TL glow curve contains two overlapping glow peaks at ∼413 and 451 K. The TL response of this phosphor was studied for different Cu concentrations and the maximum sensitivity was found at 1 mol% of Cu impurity. Other dosimetric characteristics of the synthesised nanophosphor are also presented and discussed.

  2. Longitudinal structure function from logarithmic slopes of F2 at low x

    Science.gov (United States)

    Boroun, G. R.

    2018-01-01

    Using Laplace transform techniques, I calculate the longitudinal structure function FL(x ,Q2) from the scaling violations of the proton structure function F2(x ,Q2) and make a critical study of this relationship between the structure functions at leading order (LO) up to next-to-next-to leading order (NNLO) analysis at small x . Furthermore, I consider heavy quark contributions to the relation between the structure functions, which leads to compact formula for Nf=3 +Heavy . The nonlinear corrections to the longitudinal structure function at LO up to NNLO analysis are shown in the Nf=4 (light quark flavor) based on the nonlinear corrections at R =2 and R =4 GeV-1 . The results are compared with experimental data of the longitudinal proton structure function FL in the range of 6.5 ≤Q2≤800 GeV2 .

  3. Alpha/beta(gamma ray) discrimination and spillover quantification with a BaF2 scintillator

    International Nuclear Information System (INIS)

    DeVol, T.A.; Fjeld, R.A.

    1994-01-01

    A simple pulse shape discrimination technique was used to separate alpha and beta(gamma ray) interactions in a BaF 2 scintillator. The separation was not ideal, resulting in a 5.1% spillover of alpha interactions into the beta(gamma ray) channel and 11.9% spillover of beta(gamma ray) interactions into the alpha channel for a set pulse shape discriminator. The misclassification of events was reduced by post-processing the data using either a simple analytical technique or a more complex linear least squares technique. Both techniques typically reduced the difference between the expected and calculated interaction rates to <10% when the ratio of beta(gamma ray) to alpha count rate was less than 100 : 1. ((orig.))

  4. Unbiased determination of the proton structure function F2p with faithful uncertainty estimation

    International Nuclear Information System (INIS)

    Del Debbio, Luigi; Forte, Stefano; Latorre, Jose I.; Rojo, Joan; Piccione, Andrea

    2005-01-01

    We construct a parametrization of the deep-inelastic structure function of the proton F 2 (x,Q 2 ) based on all available experimental information from charged lepton deep-inelastic scattering experiments. The parametrization effectively provides a bias-free determination of the probability measure in the space of structure functions, which retains information on experimental errors and correlations. The result is obtained in the form of a Monte Carlo sample of neural networks trained on an ensemble of replicas of the experimental data. We discuss in detail the techniques required for the construction of bias-free parameterizations of large amounts of structure function data, in view of future applications to the determination of parton distributions based on the same method. (author)

  5. Quantum mechanics of electronic-rotational energy transfer in F(2P) + H2 collisions

    International Nuclear Information System (INIS)

    Wyatt, R.E.; Walker, R.B.

    1977-01-01

    A theoretical study is made of electronic-rotational energy transfer in F( 2 P) + H 2 three-dimensional collisions, with electronic matrix elements from DIM theory. The quantum close-coupled equations are integrated via the R-matrix propagation method. Inelastic quenching probabilities are emphasized, with and without simulated open reaction channels. Interweaving patterns in the transition probability for even and odd nuclear parity vs. J (total angular momentum quantum number) are analyzed in terms of avoided crossing structure in the electrotational energy correlation diagrams. Localized regions where electronic quenching is dominant are identified in the correlation diagrams, and are confirmed in separate calculations which neglect interchannel mixing in local regions of the atom-molecule separation. Open reaction channels are found to have little influence on the quenching probabilities in these low energy calculations

  6. Correlation between TL and OSL properties of CaF2:N

    International Nuclear Information System (INIS)

    Polymeris, George S.; Kitis, George; Tsirliganis, Nestor C.

    2006-01-01

    Natural CaF 2 is very well known thermoluminescent (TL) material, since it has been extensively used as a dosimeter. Its basic advantage is the exhibited high TL sensitivity. In the present work, the optically stimulated luminescence (OSL) sensitivity of this material was studied by exposing it to environmental radiation for time intervals of few hours up to a few days, and was found to be very high. By analyzing the TL glow curves and the OSL decay curves into their individual glow-peaks and components respectively, a relation between specific glow-peaks and OSL components was established. An intense thermal transfer effect occurring during optical stimulation at high temperature was observed and an explanation is offered according to existing models

  7. Measurement of D^(*+-) Meson Production and F_2^c in Deep-Inelastic Scattering at HERA

    CERN Document Server

    Adloff, C.; Andrieu, B.; Anthonis, T.; Arkadov, V.; Astvatsatourov, A.; Babaev, A.; Bahr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bate, P.; Beglarian, A.; Behnke, O.; Beier, C.; Belousov, A.; Benisch, T.; Berger, C.; Berndt, T.; Bizot, J.C.; Boudry, V.; Braunschweig, W.; Brisson, V.; Broker, H.B.; Brown, D.P.; Bruckner, W.; Bruncko, D.; Burger, J.; Busser, F.W.; Bunyatyan, A.; Burrage, A.; Buschhorn, G.; Campbell, A.J.; Cao, Jun; Carli, T.; Caron, S.; Clarke, D.; Clerbaux, B.; Collard, C.; Contreras, J.G.; Coppens, Y.R.; Coughlan, J.A.; Cousinou, M.C.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; Davidsson, M.; Delcourt, B.; Delerue, N.; Demirchyan, R.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dingfelder, J.; Dixon, P.; Dodonov, V.; Dowell, J.D.; Droutskoi, A.; Dubak, A.; Duprel, C.; Eckerlin, Guenter; Eckstein, D.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Ferron, S.; Fleischer, M.; Fleming, Y.H.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Foster, J.M.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Garvey, J.; Gassner, J.; Gayler, Joerg; Gerhards, R.; Gerlich, C.; Ghazaryan, Samvel; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goodwin, C.; Grab, C.; Grassler, H.; Greenshaw, T.; Grindhammer, Guenter; Hadig, T.; Haidt, D.; Hajduk, L.; Haynes, W.J.; Heinemann, B.; Heinzelmann, G.; Henderson, R.C.W.; Hengstmann, S.; Henschel, H.; Heremans, R.; Herrera, G.; Herynek, I.; Hildebrandt, M.; Hilgers, M.; Hiller, K.H.; Hladky, J.; Hoting, P.; Hoffmann, D.; Horisberger, R.; Hurling, S.; Ibbotson, M.; Issever, C .; Jacquet, M.; Jaffre, M.; Janauschek, L.; Jansen, D.M.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jones, M.A.S.; Jung, H.; Kastli, H.K.; Kant, D.; Kapichine, M.; Karlsson, M.; Karschnick, O.; Keil, F.; Keller, N.; Kennedy, J.; Kenyon, I.R.; Kermiche, S.; Kiesling, Christian M.; Kjellberg, P.; Klein, M.; Kleinwort, C.; Kluge, T.; Knies, G.; Koblitz, B.; Kolya, S.D.; Korbel, V.; Kostka, P.; Kotelnikov, S.K.; Koutouev, R.; Koutov, A.; Krehbiel, H.; Kroseberg, J.; Kruger, K.; Kupper, A.; Kuhr, T.; Kurca, T.; Lahmann, R.; Lamb, D.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Laycock, P.; Lebailly, E.; Lebedev, A.; Leissner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindstroem, M.; List, B.; Lobodzinska, E.; Lobodzinski, B.; Loginov, A.; Loktionova, N.; Lubimov, V.; Luders, S.; Luke, D.; Lytkin, L.; Mahlke-Kruger, H.; Malden, N.; Malinovski, E.; Malinovski, I.; Maracek, R.; Marage, P.; Marks, J.; Marshall, R.; Martyn, H.U.; Martyniak, J.; Maxfield, S.J.; Meer, D.; Mehta, A.; Meier, K.; Merkel, P.; Meyer, A.B.; Meyer, H.; Meyer, J.; Meyer, P.O.; Mikocki, S.; Milstead, D.; Mkrtchyan, T.; Mohr, R.; Mohrdieck, S.; Mondragon, M.N.; Moreau, F.; Morozov, A.; Morris, J.V.; Muller, K.; Murin, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, T.; Nellen, G.; Newman, Paul R.; Nicholls, T.C.; Niebergall, F.; Niebuhr, C.; Nix, O.; Nowak, G.; Olsson, J.E.; Ozerov, D.; Panassik, V.; Pascaud, C.; Patel, G.D.; Peez, M.; Perez, E.; Phillips, J.P.; Pitzl, D.; Poschl, R.; Potachnikova, I.; Povh, B.; Rabbertz, K.; Radel, G.; Rauschenberger, J.; Reimer, P.; Reisert, B.; Reyna, D.; Risler, C.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rusakov, S.; Rybicki, K.; Sankey, D.P.C.; Scheins, J.; Schilling, F.P.; Schleper, P.; Schmidt, D.; Schmitt, S.; Schneider, M.; Schoeffel, L.; Schoning, A.; Schorner, T.; Schroder, V.; Schultz-Coulon, H.C.; Schwanenberger, C.; Sedlak, K.; Sefkow, F.; Chekelian, V.; Sheviakov, I.; Shtarkov, L.N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Solochenko, V.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Spitzer, H.; Stamen, R.; Stella, B.; Stiewe, J.; Straumann, U.; Swart, M.; Tasevsky, M.; Tchernyshov, V.; Chetchelnitski, S.; Thompson, Graham; Thompson, P.D.; Tobien, N.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Turney, J.E.; Tzamariudaki, E.; Udluft, S.; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vassiliev, S.; Vazdik, Y.; Vichnevski, A.; Wacker, K.; Wallny, R.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Werner, C.; Werner, M.; Werner, N.; White, G.; Wiesand, S.; Wilksen, T.; Winde, M.; Winter, G.G.; Wissing, C.; Wobisch, M.; Wunsch, E.; Wyatt, A.C.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zomer, F.; Zsembery, J.; zur Nedden, M.

    2002-01-01

    The inclusive production of D^{*+-}(2010) mesons in deep-inelastic scattering is studied with the H1 detector at HERA. In the kinematic region 11.5 GeV and |\\eta_(D^*)|<1.5. Single and double differential inclusive D^(*+-) meson cross sections are compared to perturbative QCD calculations in two different evolution schemes. The charm contribution to the proton structure, F_2^c(x,Q^2), is determined by extrapolating the visible charm cross section to the full phase space. This contribution is found to rise from about 10% at Q^2 = 1.5 GeV^2 to more than 25% at Q^2 = 60 GeV^2 corresponding to x values ranging from 5*10^(-5) to 3*10^(-3)$.

  8. Light hadrons from N{sub f}=2+1+1 dynamical twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Baron, R. [CEA, Centre de Saclay, Gif-sur-Yvette (France). IRFU/Service de Physique Nucleaire; Blossier, B.; Boucaud, P. [Paris 11 Univ., Orsay (FR). Lab. de Physique Theorique] (and others)

    2011-01-15

    We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N{sub f}=2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark masses is performed at three values of the lattice spacing a{approx}0.06 fm, a{approx}0.08 fm and a{approx}0.09 fm with lattice sizes ranging from L{approx}1.9 fm to L{approx}3.9 fm. We perform a preliminary study of SU(2) chiral perturbation theory by combining our lattice data from these three values of the lattice spacing. (orig.)

  9. B{sub K}-parameter from N{sub f}=2 twisted mass lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Constantinou, M. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Dimopoulos, P. [Roma Univ. (Italy). Dipt. di Fisica; Frezzotti, R. [Roma ' ' Tor Vergata' ' Univ. (Italy). Dipt. di Fisica; INFN, Rome (IT). Dipt. di Fisica] (and others)

    2011-01-07

    We present an unquenched N{sub f} = 2 lattice computation of the B{sub K} parameter which controls K{sup 0}- anti K{sup 0} oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B{sub K} parameter which is both multiplicatively renormalizable and O(a) improved. Employing the non-perturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B{sup RGI}{sub K}=0.729{+-}0.030, a number well in line with the existing quenched and unquenched determinations. (orig.)

  10. Radiation-induced defect production in MgF2-Co crystals

    International Nuclear Information System (INIS)

    Nuritdinov, I.; Turdanov, K.; Mirinoyatova, N.M.; Rejterov, V.M.

    1996-01-01

    Impact of Co-admixture on structural radiation defects formation in the MgF 2 crystals is studied. It is found that the Co admixture facilitates the probability of generating the F- and m-type centers of radiation defects as well as creation of the F- and M-centers, perturbed by admixtures. The availability of structural defects leads in its turn to the admixture ions perturbation. It is reflected in the removal of prohibition on spin-prohibited transitions of the Co 2 + ions. It is assumed that creation of the M-centers is the main cause for removal of the prohibition on the spin-prohibited transitions. 8 refs., 4 figs

  11. Birefringence and incipient plastic deformation in elastically overdriven [100] CaF2 under shock compression

    Science.gov (United States)

    Li, Y.; Zhou, X. M.; Cai, Y.; Liu, C. L.; Luo, S. N.

    2018-04-01

    [100] CaF2 single crystals are shock-compressed via symmetric planar impact, and the flyer plate-target interface velocity histories are measured with a laser displacement interferometry. The shock loading is slightly above the Hugoniot elastic limit to investigate incipient plasticity and its kinetics, and its effects on optical properties and deformation inhomogeneity. Fringe patterns demonstrate different features in modulation of fringe amplitude, including birefringence and complicated modulations. The birefringence is attributed to local lattice rotation accompanying incipient plasticity. Spatially resolved measurements show inhomogeneity in deformation, birefringence, and fringe pattern evolutions, most likely caused by the inhomogeneity associated with lattice rotation and dislocation slip. Transiently overdriven elastic states are observed, and the incubation time for incipient plasticity decreases inversely with increasing overdrive by the elastic shock.

  12. Axion phenomenology and θ-dependence from N{sub f}=2+1 lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Bonati, Claudio; D’Elia, Massimo; Mariti, Marco [Dipartimento di Fisica dell’Università di Pisa, Largo Pontecorvo 3, I-56127 Pisa (Italy); INFN sezione di Pisa,Largo Pontecorvo 3, I-56127 Pisa (Italy); Martinelli, Guido [Dipartimento di Fisica dell’Università di Roma “La Sapienza”, Piazzale Aldo Moro 5, I-00185 Roma (Italy); INFN Sezione di Roma La Sapienza,Piazzale Aldo Moro 5, I-00185 Roma (Italy); Mesiti, Michele [Dipartimento di Fisica dell’Università di Pisa, Largo Pontecorvo 3, I-56127 Pisa (Italy); INFN sezione di Pisa,Largo Pontecorvo 3, I-56127 Pisa (Italy); Negro, Francesco [INFN sezione di Pisa,Largo Pontecorvo 3, I-56127 Pisa (Italy); Sanfilippo, Francesco [School of Physics and Astronomy, University of Southampton,SO17 1BJ Southampton (United Kingdom); Villadoro, Giovanni [Abdus Salam International Centre for Theoretical Physics,Strada Costiera 11, 34151, Trieste (Italy)

    2016-03-22

    We investigate the topological properties of N{sub f}=2+1 QCD with physical quark masses, both at zero and finite temperature. We adopt stout improved staggered fermions and explore a range of lattice spacings a∼0.05−0.12 fm. At zero temperature we estimate both finite size and finite cut-off effects, comparing our continuum extrapolated results for the topological susceptibility χ with predictions from chiral perturbation theory. At finite temperature, we explore a region going from T{sub c} up to around 4 T{sub c}, where we provide continuum extrapolated results for the topological susceptibility and for the fourth moment of the topological charge distribution. While the latter converges to the dilute instanton gas prediction the former differs strongly both in the size and in the temperature dependence. This results in a shift of the axion dark matter window of almost one order of magnitude with respect to the instanton computation.

  13. ADS based on NaF-PbF2 molten salt

    International Nuclear Information System (INIS)

    Volk, V.I.; Vakhrushin, A.Yu.; Kwaratzkheli, A.Yu.; Konev, V.N.; Kochurov, B.P.; Shvedov, O.V.

    1999-01-01

    The neutron-physical parameters of an accelerator driven system (ADS) with a proton accelerator feeding a sub-critical molten salt blanket are investigated. The installation is designed for the production of electric power, involving thorium in a fuel cycle, transmutation of fission products and actinides. It is supposed to use fluoride salt composition 66PbF 2 -34NaF with addition of heavy elements (Th, Np, Pu and minor actinides) as the material of fuel, coolant and target. The thermal power of this ADS is 2000 MW. The current of the 1 GeV proton beam is 29 mA. The investigations are carried out for the following fuel cycles: the plutonium one, the burning of Np and minor actinides and the plutonium-thorium cycle. The balances of nuclides systems under supposition of its continuous operation during 20 years are presented [ru

  14. Evaluation of the kinetic parameters of CaF2:Tm (TLD-300) thermoluminescence dosemeters

    International Nuclear Information System (INIS)

    Azorin, Juan; Gutierrez, Alicia; Furetta, Claudio

    1989-01-01

    The kinetic parameters of the first, third and fifth peaks of CaF 2 :Tm (TLD-300) dosemeters were determined experimentally using methods based on initial rise, peak shape, different heating rates, isothermal decay and numerical fitting method and a comparison was made between the results obtained. The average activation energy values determined by the methods used here were 0.72, 1.16 and 1.77 eV, with mean values for the frequency factor of 2.58 x 10 8 , 2.89 x 10 13 and 6.16 x 10 16 s -1 for the first, third and fifth peaks respectively. The values of activation energy obtained for each peak using the different methods covered a spread of about 4%. However, the spread for each of the frequency factors was very high. (author)

  15. Radiation dosimetry by optically stimulated phosphorescence of CaF2:Mn

    International Nuclear Information System (INIS)

    Bernhardt, R.

    1974-01-01

    In addition to the light emission which occurs in TL, trapped electrons in CaF 2 :Mn can also be released by stimulation with visible and UV light. The measurement of stimulated light emission is disturbed by illumination. But there is an optically-stimulated phosphorescence, which permits to separate measurement of stimulated light emission and illumination. A theory is given. During illumination a part of the released electrons are captured by flat traps, which are emptied at room temperature. A dose dependent signal can be measured at a defined time after the stimulating pulse of visible light. Dosimeters (CaF 2 :Mn teflon disks) were illuminated by the light of a tungsten lamp. The dose response curve was found to be linear from 1 to 10 5 rads. The response curve obtained for optical stimulation was similar to the TL-response curve. Fading of the optically-stimulated signal was higher than TL-fading. Repeated readings of a single sample are possible. The number of readings is dependent on illumination conditions. Accuracy of sample to sample was about 3.5% (standard deviation). There are two background signals. (1) Post-irradiation phosphorescence occurs. Flat traps are also filled after 60 Co gamma excitation. The measurement of the signal is possible after decay of post-irradiation phosphorescence. (2) There is an optically-excited phosphorescence, which also occurs if all trapped electrons are released. The lower limit of dose measurements is given by deviations of optically-excited emission and the dark-current of the photomultiplier tube. (author)

  16. Statistical properties of the deviations of f 0 F 2 from monthly medians

    Directory of Open Access Journals (Sweden)

    Y. Tulunay

    2002-06-01

    Full Text Available The deviations of hourly f 0 F 2 from monthly medians for 20 stations in Europe during the period 1958-1998 are studied. Spectral analysis is used to show that, both for original data (for each hour and for the deviations from monthly medians, the deterministic components are the harmonics of 11 years (solar cycle, 1 year and its harmonics, 27 days and 12 h 50.49 m (2nd harmonic of lunar rotation period L 2 periodicities. Using histograms for one year samples, it is shown that the deviations from monthly medians are nearly zero mean (mean < 0.5 and approximately Gaussian (relative difference range between %10 to %20 and their standard deviations are larger for daylight hours (in the range 5-7. It is shown that the amplitude distribution of the positive and negative deviations is nearly symmetrical at night hours, but asymmetrical for day hours. The positive and negative deviations are then studied separately and it is observed that the positive deviations are nearly independent of R12 except for high latitudes, but negative deviations are modulated by R12 . The 90% confidence interval for negative deviations for each station and each hour is computed as a linear model in terms of R12. After correction for local time, it is shown that for all hours the confidence intervals increase with latitude but decrease above 60N. Long-term trend analysis showed that there is an increase in the amplitude of positive deviations from monthly means irrespective of the solar conditions. Using spectral analysis it is also shown that the seasonal dependency of negative deviations is more accentuated than the seasonal dependency of positive deviations especially at low latitudes. In certain stations, it is also observed that the 4th harmonic of 1 year corresponding to a periodicity of 3 months, which is missing in f 0 F 2 data, appears in the spectra of negative variations.

  17. Persistence of the planetary wave type oscillations in foF2 over Europe

    Directory of Open Access Journals (Sweden)

    J. Laštovička

    2003-07-01

    Full Text Available Planetary waves are oscillations of very predominantly tropospheric origin with typical periods of about 2–30 days. Their dominant zonal wave numbers are 1, 2 and 3, i.e. the waves are of large-scale (global character. The planetary wave type oscillations have been observed in the lower and middle atmosphere but also in the ionosphere, including the ionospheric F2-layer. Here, we deal only with the oscillations analyzed for four European stations over a solar cycle with the use of the Meyer and Morlet wavelet transforms. Waves with periods near 5, 10 and 16 days are studied. Only events with a duration of three wave-cycles and more are considered. The 5-day period wave events display a typical duration of 4 cycles, while 10- and 16-day wave events are less persistent, with a typical duration of about 3.5 cycles and 3 cycles, respectively. The persistence pattern in terms of number of cycles and in terms of number of days is different. In terms of number of cycles, the typical persistence of oscillations decreases with increasing period. On the other hand, in terms of number of days the typical persistence evidently increases with increasing period. The spectral distribution of event duration is too broad to allow for a reasonable prediction of event duration. Thus, the predictability of the planetary wave type oscillations in foF2 seems to be very questionable.Key words. Ionosphere (ionosphere-atmosphere interaction, mid-latitude ionosphere, ionospheric disturbances – Meteorology and atmospheric dynamics (waves and tides

  18. Study of the OSL response of the CaF2:Dy (TLD-200) dosimeter

    International Nuclear Information System (INIS)

    Medeiros, Beatriz M.; Alencar, Marcus A.V. de

    2013-01-01

    The OSL dosimetry has become, in recent years, a successful technique in personal and environmental dosimetry due to high luminescence efficiency, excellent reproducibility, fast readout of signal and repeated and successive OSL measurements of the same dosimeter. Another factor that contributes to the increased use of OSL dosimetry is the use of the aluminum oxide doped with carbon (Al 2 O 3 :C) as dosimeter. Developed initially as thermoluminescent dosimeter, the Al 2 O 3 :C has an excellent OSL sensitivity, high efficiency, good linearity, low or no fading and excellent stability with respect to environmental conditions. However, the OSL dose response for aluminum oxide is linear only for low doses. For intermediate doses (doses in radiotherapy), the response is supralinear. For the values of high doses used in the processes of food irradiation and sterilization of surgical materials, the OSL signal of the aluminum oxide already saturated. Furthermore, the degree of supralinearity and the saturation value vary from sample to sample (∼ 30-300 Gy). Therefore, the use of aluminum oxide as OSL dosimeter is inappropriate in radiotherapy and in the irradiation industrial processes. The objective of this work is the study of the OSL properties of other dosimetric materials irradiated with values of intermediate and high dose to verify the applicability of the OSL dosimetry in radiotherapy and in the processes of food irradiation and sterilization of medical materials. The dosimetric material used in this work is the calcium fluoride doped with dysprosium (CaF 2 :Dy) produced by Harshaw and known commercially as TLD-200. The results demonstrate that the CaF 2 :Dy has OSL signal and the OSL dose response is linear in the range of 10 Gy to 300 Gy. Therefore, the dosimetry OSL with this dosimeter can be used in the evaluation of doses of the order of dozens to hundreds of grays. (author)

  19. Distinguishing between MSSM and NMSSM through ΔF=2 processes

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Jacky [Department of High Energy Physics, Tata Institute of Fundamental Research,Ist Homi Bhabha road, 400 005 Mumbai (India); Paraskevas, Michael [Department of Physics, Division of Theoretical Physics, University of Ioannina,GR 45110 Ioannina (Greece)

    2016-10-25

    We study deviations between MSSM and Z{sub 3}-invariant NMSSM, with respect to their predictions in ΔF=2 processes. We find that potentially significant effects arise either from the well known double-penguin diagrams, due to the extra scalar NMSSM states, or from neutralino-gluino box contributions, due to the extended neutralino sector. Both are discussed to be effective in the large tan β regime. Enhanced genuine-NMSSM contributions in double penguins are expected for a light singlet spectrum (CP-even, CP-odd), while the magnitude of box effects is primarily controlled through singlino mixing. The latter is found to be typically subleading (but non-negligible) for λ≲0.5, however it can become dominant for λ∼O(1). We also study the low tan β regime, where a distinction between MSSM and NMSSM can come instead due to experimental constraints, acting differently on the allowed parameter space of each model. To this end, we incorporate the LHC Run-I limits from H→Z Z, A→h Z and H{sup ±}→τ ν non-observation along with Higgs observables and set (different) upper bounds for new physics contributions in ΔF=2 processes. We find that a ∼25% contribution in ΔM{sub s(d)} is still possible for MFV models, however such a large effect is nowadays severely constrained for the case of MSSM, due to stronger bounds on the charged Higgs masses.

  20. The effect of inhibition of prostaglandin F2 alpha synthesis on placental expulsion in the ewe.

    Science.gov (United States)

    Chassagne, M; Barnouin, J

    1993-04-01

    Five ewes were injected with two doses of a nonsteroidal anti-inflammatory drug (NSAI), lysine acetyl salicylate, at birth of their first lamb and one hour later, and five others were injected once only, at birth of their first lamb. A control group of six animals was constituted. The times needed for fetal expulsion and placental release were recorded. The peripheral plasma PgF2 alpha (as PGFM) levels were measured prepartum during the seven last days of gestation, at parturition, then 1 h, 2 h and 12 h after lambing. The results were compared among and within treatment groups. They indicate that the physiological increase in peripheral PGFM levels starts two days before lambing and that the level peaks at lambing. The normal decrease after parturition is emphasized by NSAI injections as detected 1 h and 2 h posttreatment (p NSAI drug is short-acting as revealed by the lower PGFM levels in twice-treated animals 2 h after birth compared to once treated animals and the similar low levels in all three groups 12 h after birth. The fetal membranes were expelled normally in all treated and nontreated animals, but the time needed for placental expulsion in ewes injected with two doses of NSAI was longer than in controls (p < 0.05). A negative correlation (p < 0.05) was found between plasma PGFM levels measured two hours after lambing and the time needed for fetal membrane expulsion. PgF2 alpha appears to have a role in placental release in the ewe.

  1. PB1-F2 Protein Does Not Impact the Virulence of Triple-Reassortant H3N2 Swine Influenza Virus in Pigs but Alters Pathogenicity and Transmission in Turkeys.

    Science.gov (United States)

    Deventhiran, Jagadeeswaran; Kumar, Sandeep R P; Raghunath, Shobana; Leroith, Tanya; Elankumaran, Subbiah

    2016-01-01

    PB1-F2 protein, the 11th influenza A virus (IAV) protein, is considered to play an important role in primary influenza virus infection and postinfluenza secondary bacterial pneumonia in mice. The functional role of PB1-F2 has been reported to be a strain-specific and host-specific phenomenon. Its precise contribution to the pathogenicity and transmission of influenza virus in mammalian host, such as swine, and avian hosts, such as turkeys, remain largely unknown. In this study, we explored the role of PB1-F2 protein of triple-reassortant (TR) H3N2 swine influenza virus (SIV) in pigs and turkeys. Using the eight-plasmid reverse genetics system, we rescued wild-type SIV A/swine/Minnesota/1145/2007 (H3N2) (SIV 1145-WT), a PB1-F2 knockout mutant (SIV 1145-KO), and its N66S variant (SIV 1145-N66S). The ablation of PB1-F2 in SIV 1145 modulated early-stage apoptosis but did not affect the viral replication in swine alveolar macrophage cells. In pigs, PB1-F2 expression did not affect nasal shedding, lung viral load, immunophenotypes, and lung pathology. On the other hand, in turkeys, SIV 1145-KO infected poults, and its in-contacts developed clinical signs earlier than SIV 1145-WT groups and also displayed more extensive histopathological changes in intestine. Further, turkeys infected with SIV 1145-N66S displayed poor infectivity and transmissibility. The more extensive histopathologic changes in intestine and relative transmission advantage observed in turkeys infected with SIV 1145-KO need to be further explored. Taken together, these results emphasize the host-specific roles of PB1-F2 in the pathogenicity and transmission of IAV. Novel triple-reassortant H3N2 swine influenza virus emerged in 1998 and spread rapidly among the North American swine population. Subsequently, it showed an increased propensity to reassort, generating a range of reassortants. Unlike classical swine influenza virus, TR SIV produces a full-length PB1-F2 protein, which is considered an important

  2. Hydrodechlorination of Tetrachloromethane over Palladium Catalysts Supported on Mixed MgF2-MgO Carriers

    Directory of Open Access Journals (Sweden)

    Magdalena Bonarowska

    2016-11-01

    Full Text Available Pd/MgO, Pd/MgF2 and Pd/MgO-MgF2 catalysts were investigated in the reaction of CCl4 hydrodechlorination. All the catalysts deactivated in time on stream, but the degree of deactivation varied from catalyst to catalyst. The MgF2-supported palladium with relatively large metal particles appeared the best catalyst, characterized by good activity and selectivity to C2-C5 hydrocarbons. Investigation of post-reaction catalyst samples allowed to find several details associated with the working state of hydrodechlorination catalysts. The role of support acidity was quite complex. On the one hand, a definite, although not very high Lewis acidity of MgF2 is beneficial for shaping high activity of palladium catalysts. The MgO-MgF2 support characterized by stronger Lewis acidity than MgF2 contributes to very good catalytic activity for a relatively long reaction period (~5 h but subsequent neutralization of stronger acid centers (by coking eliminates them from the catalyst. On the other hand, the role of acidity evolution, which takes place when basic supports (like MgO are chlorided during HdCl reactions, is difficult to assess because different events associated with distribution of chlorided support species, leading to partial or even full blocking of the surface of palladium, which plays the role of active component in HdCl reactions.

  3. Spectroscopic properties of Er3+ and Yb3+ co-doped glass ceramics containing SrF2 nanocrystals

    International Nuclear Information System (INIS)

    Qiao Xvsheng; Fan Xianping; Wang Minquan; Zhang Xianghua

    2009-01-01

    The spectroscopic properties of Er 3+ /Yb 3+ co-doped 50SiO 2 -10Al 2 O 3 -20ZnF 2 -20SrF 2 glass and glass ceramic containing SrF 2 nanocrystals were investigated. The formation of SrF 2 nanocrystals in the glass ceramic was confirmed by XRD. The oscillator strengths for several transitions of the Er 3+ ions in the glass ceramic have been obtained and the Judd-Ofelt parameters were then determined. The XRD result and Judd-Ofelt parameters suggested that Er 3+ and Yb 3+ ions had efficiently enriched in the SrF 2 nanocrystals in the glass ceramic. The lifetime of excited states has been used to reveal the surroundings of luminescent Er 3+ and Yb 3+ and energy transfer (ET) mechanism between Er 3+ and Yb 3+ . Much stronger upconversion luminescence and longer lifetime of the Er 3+ /Yb 3+ co-doped glass ceramic were observed in comparison with the Er 3+ /Yb 3+ co-doped glass, which could be ascribed to more efficient ET from Yb 3+ to Er 3+ due to the enrichment of Yb 3+ and Er 3+ and the shortening of the distance between lanthanide ions in the precipitated SrF 2 nanocrystals.

  4. Exposure to welding fumes is associated with hypomethylation of the F2RL3 gene: a cardiovascular disease marker.

    Science.gov (United States)

    Hossain, Mohammad B; Li, Huiqi; Hedmer, Maria; Tinnerberg, Håkan; Albin, Maria; Broberg, Karin

    2015-12-01

    Welders are at risk for cardiovascular disease. Recent studies linked tobacco smoke exposure to hypomethylation of the F2RL3 (coagulation factor II (thrombin) receptor-like 3) gene, a marker for cardiovascular disease prognosis and mortality. However, whether welding fumes cause hypomethylation of F2RL3 remains unknown. We investigated 101 welders (median span of working as a welder: 7 years) and 127 unexposed controls (non-welders with no obvious exposure to respirable dust at work), age range 23-60 years, all currently non-smoking, in Sweden. The participants were interviewed about their work history, lifestyle factors and diseases. Personal sampling of respirable dust was performed for the welders. DNA methylation of F2RL3 in blood was assessed by pyrosequencing of four CpG sites, CpG_2 (corresponds to cg03636183) to CpG_5, in F2RL3. Multivariable linear regression analysis was used to assess the association between exposure to welding fumes and F2RL3 methylation. Welders had 2.6% lower methylation of CpG_5 than controls (pWelding fumes exposure and previous smoking were associated with F2RL3 hypomethylation. This finding links low-to-moderate exposure to welding fumes to adverse effects on the cardiovascular system, and suggests a potential mechanistic pathway for this link, via epigenetic effects on F2RL3 expression. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. CYP79F1 and CYP79F2 have distinct functions in the biosynthesis of aliphatic glucosinolates in Arabidopsis.

    Science.gov (United States)

    Chen, Sixue; Glawischnig, Erich; Jørgensen, Kirsten; Naur, Peter; Jørgensen, Bodil; Olsen, Carl-Erik; Hansen, Carsten H; Rasmussen, Hasse; Pickett, John A; Halkier, Barbara A

    2003-03-01

    Cytochromes P450 of the CYP79 family catalyze the conversion of amino acids to oximes in the biosynthesis of glucosinolates, a group of natural plant products known to be involved in plant defense and as a source of flavor compounds, cancer-preventing agents and bioherbicides. We report a detailed biochemical analysis of the substrate specificity and kinetics of CYP79F1 and CYP79F2, two cytochromes P450 involved in the biosynthesis of aliphatic glucosinolates in Arabidopsis thaliana. Using recombinant CYP79F1 and CYP79F2 expressed in Escherichia coli and Saccharomyces cerevisiae, respectively, we show that CYP79F1 metabolizes mono- to hexahomomethionine, resulting in both short- and long-chain aliphatic glucosinolates. In contrast, CYP79F2 exclusively metabolizes long-chain elongated penta- and hexahomomethionines. CYP79F1 and CYP79F2 are spatially and developmentally regulated, with different gene expression patterns. CYP79F2 is highly expressed in hypocotyl and roots, whereas CYP79F1 is strongly expressed in cotyledons, rosette leaves, stems, and siliques. A transposon-tagged CYP79F1 knockout mutant completely lacks short-chain aliphatic glucosinolates, but has an increased level of long-chain aliphatic glucosinolates, especially in leaves and seeds. The level of long-chain aliphatic glucosinolates in a transposon-tagged CYP79F2 knockout mutant is substantially reduced, whereas the level of short-chain aliphatic glucosinolates is not affected. Biochemical characterization of CYP79F1 and CYP79F2, and gene expression analysis, combined with glucosinolate profiling of knockout mutants demonstrate the functional role of these enzymes. This provides valuable insights into the metabolic network leading to the biosynthesis of aliphatic glucosinolates, and into metabolic engineering of altered aliphatic glucosinolate profiles to improve nutritional value and pest resistance.

  6. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available mixed short sisal/glass hybrid fibre reinforced low density polyethylene composites was investigated by Kalaprasad et al [25].Chemical surface modifications such as alkali, acetic anhydride, stearic acid, permanganate, maleic anhydride, silane...

  7. Stringent tests of constrained Minimal Flavor Violation through ΔF=2 transitions

    International Nuclear Information System (INIS)

    Buras, Andrzej J.; Girrbach, Jennifer

    2013-01-01

    New Physics contributions to ΔF=2 transitions in the simplest extensions of the Standard Model (SM), the models with constrained Minimal Flavor Violation (CMFV), are parametrized by a single variable S(v), the value of the real box diagram function that in CMFV is bounded from below by its SM value S 0 (x t ). With already very precise experimental values of ε K , ΔM d , ΔM s and precise values of the CP-asymmetry S ψK S and of B K entering the evaluation of ε K , the future of CMFV in the ΔF = 2 sector depends crucially on the values of vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke, γ, F B s √(B B s ) and F B d √(B B d ). The ratio ξ of the latter two non-perturbative parameters, already rather precisely determined from lattice calculations, allows then together with ΔM s / ΔM d and S ψK S to determine the range of the angle γ in the unitarity triangle independently of the value of S(v). Imposing in addition the constraints from vertical stroke ε K vertical stroke and ΔM d allows to determine the favorite CMFV values of vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke, F B s √(B B s ) and F B d √(B B d ) as functions of S(v) and γ. The vertical stroke V cb vertical stroke 4 dependence of ε K allows to determine vertical stroke V cb vertical stroke for a given S(v) and γ with a higher precision than it is presently possible using tree-level decays. The same applies to vertical stroke V ub vertical stroke, vertical stroke V td vertical stroke and vertical stroke V ts vertical stroke that are automatically determined as functions of S(v) and γ. We derive correlations between F B s √(B B s ) and F B d √(B B d ), vertical stroke V cb vertical stroke, vertical stroke V ub vertical stroke and γ that should be tested in the coming years. Typically F B s √(B B s ) and F B d √(B B d ) have to be lower than their present lattice values, while vertical stroke V cb vertical stroke has to

  8. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  9. The Effect of Parasitism and Interpopulation Hybridization on Aedes albopictus (Diptera: Culicidae) Fitness.

    Science.gov (United States)

    Tseng, Michelle

    2017-09-01

    Recent research in mosquito population genetics suggests that interpopulation hybridization has likely contributed to the rapid spread of the container-breeding mosquitoes. Here, I used laboratory experiments to investigate whether interpopulation Aedes (Stegomyia) albopictus (Skuse) F1 and F2 hybrids exhibit higher fitness than parental populations, and whether hybrid mosquito performance is related to infection by the coevolved protozoan parasite Ascogregarina taiwanensis (Lien and Levine). Overall, there were significant differences in development time, wing length, and survival between the two parental mosquito populations, but no difference in per capita growth rate r. Hybrid mosquitoes were generally intermediate in phenotype to the parentals, except that F2 females were significantly larger than the midparent average. In addition, As. taiwanensis parasites produced fewest oocysts when they were reared in hosts of hybrid origin. These data suggest that hybridization between previously isolated mosquito populations can result in slight increases in potential mosquito reproductive success, via increased hybrid body size, and via the temporary escape from coevolved parasites. These findings are significant because studies have shown that even slight hybrid vigor can have positive fitness consequences for population persistence. Although this was a laboratory experiment extending only to the F2 generation, many other invasive insects also carry coevolved parasites, and thus the patterns seen in this mosquito system may be broadly relevant. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Increased F3-Isoprostanes in the Canadian Inuit Population Could Be Cardioprotective by Limiting F2-Isoprostane Production.

    Science.gov (United States)

    Alkazemi, Dalal; Jackson, Robert L; Chan, Hing Man; Kubow, Stan

    2016-09-01

    F3-isoprostanes (F3-IsoPs), derived from peroxidation of eicosapentaenoic acid (C20:5n-3), could be cardioprotective by limiting production of F2-isoprostanes (F2-IsoPs), a cardiovascular disease risk factor. The objective of the study was to determine whether the n-3-polyunsaturated (PUFA)-rich Inuit diet is associated with a lower plasma ratio of F2-IsoPs to F3-IsoPs. This was a cross-sectional observational study. The study was conducted in 36 Canadian Arctic Inuit communities. Participants included a random subset (n = 233) of Inuit adults taken from a population-based survey. Plasma F2-IsoPs and F3-IsoPs, cardiometabolic risk factors (blood lipids, C-reactive protein, blood pressure, fasting glucose) and markers of dietary exposure (erythrocyte n-3 and n-6 PUFA, blood levels of Se, mercury, polychlorinated biphenyls) were measured. Inuit aged 40 years old and older vs younger Inuit showed higher concentrations of plasma F3-IsoPs and erythrocyte n-3 PUFA and lower plasma F2-IsoPs concentrations despite having higher blood lipids, fasting glucose, systolic blood pressure, and percentage body fat. Plasma F3-IsoPs were not associated with any cardiometabolic measures. When subjects were categorized into tertiles according to total n-3 PUFA erythrocyte concentrations, F3-IsoPs increased with increasing tertiles, whereas the F2-IsoP to F3-IsoP ratio was lowest at the highest n-3 tertile. The F2-IsoP to F3-IsoP ratio was significantly predicted by C20:5n-3 (β= -.365, P = .002); C20:4n-6:C20:5n-3 (β = .056, P = .006), blood mercury (β = -.812, P =.015), blood Se (β = -1.95, P = .015), and smoking (β = .745, P = .025). Plasma F3-IsoPs were not associated with cardiometabolic risk factors previously seen with F2-IsoPs. Higher n-3 fatty acid status was associated with lower plasma F2-IsoPs and higher plasma F3-IsoPs, which provides partial explanation to the cardioprotective effects of the n-3 PUFA-rich Inuit diet.

  11. Optical Spectra Properties and Continuous-Wave Laser Performance of Tm,Y:CaF2 Single Crystals

    Directory of Open Access Journals (Sweden)

    Jingxin Ding

    2018-01-01

    Full Text Available 3 at.% Tm, x at.% Y:CaF2 crystals (x=0, 0.5, 1, 2, and 3 were grown by the vertical Bridgman method and investigated. Codoping Y3+ ions can manipulate the local structure of Tm3+ ions in the CaF2 crystal and then improve the spectroscopic properties. Compared with 3 at.% Tm:CaF2, 3 at.% Tm, 3 at.% Y:CaF2 crystal has several advantages. Firstly, the absorption cross section is improved from 0.35 × 10−20 cm−2 to 0.45 × 10−20 cm−2 at 767 nm, and the fluorescence intensity had elevated 3.4 times. Secondly, the linewidth of the fluorescence spectrum and lifetime also increased from 164 nm to 191 nm and from 6.16 ms to 8.15 ms at room temperature, respectively. Furthermore, quantum efficiency improved from 58.2% to 80.3%. The maximum laser output power of 583 mW and slope efficiency of 25.3% were achieved in 3 at.% Tm, 3 at.% Y:CaF2 crystal under 790 nm diode pumping.

  12. Crystallization kinetics and spectroscopic investigations on Tb3+ and Yb3+ codoped glass ceramics containing CaF2 nanocrystals

    International Nuclear Information System (INIS)

    Huang Lihui; Qin Guanshi; Arai, Yusuke; Jose, Rajan; Suzuki, Takenobu; Ohishi, Yasutake; Yamashita, Tatsuya; Akimoto, Yusuke

    2007-01-01

    Transparent Tb 3+ and Yb 3+ codoped oxyfluoride glass ceramics containing CaF 2 nanocrystals were prepared by melt quenching and subsequent heat treatment. Crystallization kinetics of CaF 2 nanocrystals was investigated by differential scanning calorimetric method. The average apparent activation energy E a of the crystallization was ∼498 kJ/mol. Moreover, the value of the Avrami exponent n was 1.01. These results suggest that the crystallization mechanism of CaF 2 is a diffusion controlled growth process of needles and plates of finite long dimensions. X-ray diffraction patterns and transmission electron microscopy image confirmed the CaF 2 nanocrystals in the glass ceramic. Ultraviolet (UV) and visible emission spectra of the as-made glass and the glass ceramic with an excitation of a 974 nm laser diode were recorded at room temperature. An intense UV emission at 381 nm was observed in the glass ceramic. The origin of the enhancement of the emission at 381 nm was investigated using spectroscopic technique and Judd-Ofelt analysis. The enhancement of the emission at 381 nm could be attributed to the change of the ligand field of Tb 3+ ions due to the incorporation of some Tb 3+ and Yb 3+ ions into CaF 2 nanocrystals in the glass ceramic

  13. Amplitude and phase of distortion product otoacoustic emissions in the guinea pig in an (f1,f2) area study

    Science.gov (United States)

    Schneider, Sandra; Prijs, Vera F.; Schoonhoven, Ruurd

    2003-06-01

    Lower sideband distortion product otoacoustic emissions (DPOAEs), measured in the ear canal upon stimulation with two continuous pure tones, are the result of interfering contributions from two different mechanisms, the nonlinear distortion component and the linear reflection component. The two contributors have been shown to have a different amplitude and, in particular, a different phase behavior as a function of the stimulus frequencies. The dominance of either component was investigated in an extensive (f1,f2) area study of DPOAE amplitude and phase in the guinea pig, which allows for both qualitative and quantitative analysis of isophase contours. Making a minimum of additional assumptions, simple relations between the direction of constant phase in the (f1,f2) plane and the group delays in f1-sweep, f2-sweep, and fixed f2/f1 paradigms can be derived, both for distortion (wave-fixed) and reflection (place-fixed) components. The experimental data indicate the presence of both components in the lower sideband DPOAEs, with the reflection component as the dominant contributor for low f2/f1 ratios and the distortion component for intermediate ratios. At high ratios the behavior cannot be explained by dominance of either component.

  14. Anisotropic power spectrum and bispectrum in the f(ϕ)F2 mechanism

    Science.gov (United States)

    Bartolo, Nicola; Matarrese, Sabino; Peloso, Marco; Ricciardone, Angelo

    2013-01-01

    A suitable coupling of the inflaton φ to a vector kinetic term F2 gives frozen and scale invariant vector perturbations. We compute the cosmological perturbations ζ that result from such coupling by taking into account the classical vector field that unavoidably gets generated at large scales during inflation. This generically results in a too-anisotropic power spectrum of ζ. Specifically, the anisotropy exceeds the 1% level (10% level) if inflation lasts ˜5 e-folds (˜50 e-folds) more than the minimal amount required to produce the cosmic microwave background modes. This conclusion applies, among others, to the application of this mechanism for magnetogenesis, for anisotropic inflation, and for the generation of anisotropic perturbations at the end of inflation through a waterfall field coupled to the vector (in this case, the unavoidable contribution that we obtain is effective all throughout inflation, and it is independent of the waterfall field). For a tuned duration of inflation, a 1% (10%) anisotropy in the power spectrum corresponds to an anisotropic bispectrum which is enhanced like the local one in the squeezed limit, and with an effective local fNL˜3(˜30). More in general, a significant anisotropy of the perturbations may be a natural outcome of all models that sustain higher than 0 spin fields during inflation.

  15. Determination of UO2F2, UO2 and UF4 in tetrafluoride of uranium samples

    International Nuclear Information System (INIS)

    Contreras Guzman, Ariel; Arlegui Hormazabal, Oscar

    2003-01-01

    The combustible elements for investigation reactors that at the present are manufacturing by the Chilean Nuclear Energy Commission (CCHEN) they are based on aluminum and silicide uranium powdered which is obtained from metallic uranium. At the present the Conversion Units, is developing the technology of transformation UF 6 in metallic Uranium, reason for which is necessary that the Chemical Analysis Laboratory have a methodology that allows to quantify the presence of UO 2 F 2 , UO 2 and UF 4 in the samples obtained in this transformation process. For this reason we are implements the methodology of sequential analysis that had been developed previously, for the Institute of Energy and Nuclear Investigations, IPEN Brasil, and to adapt it to the present conditions in the Laboratory of Chemical Analysis of the CCHEN. This method is based on the different solubilities that present those sample in front of solvents as ethanol and solutions of ammonium oxalate, what allows the separation of these compounds for a later analysis by means of the method of Davies and Gray. This method is based on the reduction of the uranium (VI) to uranium (IV) with ferrous ion amid phosphoric acid, quantifying the present uranium in the samples by means of titration with potassium dicromate. With the purpose of checking the efficiency of the method, the sum of all values of uranium coming from each compound and compares it with the total uranium of the sample (author)

  16. Classifying oxidative stress by F2-isoprostane levels across human diseases: A meta-analysis.

    Science.gov (United States)

    van 't Erve, Thomas J; Kadiiska, Maria B; London, Stephanie J; Mason, Ronald P

    2017-08-01

    The notion that oxidative stress plays a role in virtually every human disease and environmental exposure has become ingrained in everyday knowledge. However, mounting evidence regarding the lack of specificity of biomarkers traditionally used as indicators of oxidative stress in human disease and exposures now necessitates re-evaluation. To prioritize these re-evaluations, published literature was comprehensively analyzed in a meta-analysis to quantitatively classify the levels of systemic oxidative damage across human disease and in response to environmental exposures. In this meta-analysis, the F 2 -isoprostane, 8-iso-PGF 2α , was specifically chosen as the representative marker of oxidative damage. To combine published values across measurement methods and specimens, the standardized mean differences (Hedges' g) in 8-iso-PGF 2α levels between affected and control populations were calculated. The meta-analysis resulted in a classification of oxidative damage levels as measured by 8-iso-PGF 2α across 50 human health outcomes and exposures from 242 distinct publications. Relatively small increases in 8-iso-PGF 2α levels (ganalysis of published data. This analysis provides knowledge on the true involvement of oxidative damage across human health outcomes as well as utilizes past research to prioritize those conditions requiring further scrutiny on the mechanisms of biomarker generation. Copyright © 2017. Published by Elsevier B.V.

  17. Epistasis between QTLs for bone density variation in Copenhagen × dark agouti F2 rats

    Science.gov (United States)

    Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J.; Foroud, Tatiana; Turner, Charles H.

    2010-01-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted bone density (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine genome-wide significance thresholds for the full model and epistasis (interaction) LOD scores corresponding to an alpha level of 0.01. A novel locus on chromosome 15 and a previously reported chromosome 14 QTL demonstrated a strong epistatic effect on BMD at the femur by DXA (LOD = 5.4). Two novel QTLs on chromosomes 2 and 12 were found to interact to affect total BMD at the femur midshaft by pQCT (LOD = 5.0). These results provide new information regarding the mode of action of previously identified QTL in the rat, as well as identifying novel loci that act in combination with known QTL or with other novel loci to contribute to BMD variation. PMID:19153792

  18. Epistasis between QTLs for bone density variation in Copenhagen x dark agouti F2 rats.

    Science.gov (United States)

    Koller, Daniel L; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J; Foroud, Tatiana; Turner, Charles H

    2009-03-01

    The variation in several of the risk factors for osteoporotic fracture, including bone mineral density (BMD), has been shown to be strongly influenced by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 828 F2 progeny of Copenhagen and dark agouti rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted bone density (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine genome-wide significance thresholds for the full model and epistasis (interaction) LOD scores corresponding to an alpha level of 0.01. A novel locus on chromosome 15 and a previously reported chromosome 14 QTL demonstrated a strong epistatic effect on BMD at the femur by DXA (LOD = 5.4). Two novel QTLs on chromosomes 2 and 12 were found to interact to affect total BMD at the femur midshaft by pQCT (LOD = 5.0). These results provide new information regarding the mode of action of previously identified QTL in the rat, as well as identifying novel loci that act in combination with known QTL or with other novel loci to contribute to BMD variation.

  19. Multi-Phonon Relaxation of H^- Local Modes in CaF_2

    Science.gov (United States)

    Davison, C. P.; Happek, U.; Campbell, J. A.; Engholm, J. R.; Schwettman, H. A.

    1998-03-01

    Local modes play an important role in the relaxation of vibrational modes of small molecules in solids (J.R. Engholm, C.W. Rella, H.A. Schwettman, and U. Happek; Phys. Rev. Lett. 77), 1302 (1996)., but only few attempts have been reported to study the relaxation of these local modes. Here we report on experiments to investigate the non-radiative relaxation of H^- local modes in CaF_2. Using a pump-probe technique, saturation experiments on the H^- local modes, both interstitial and substitutional, were performed at the Stanford Free Electron Laser Center. At low temperature we find a relaxation time T1 of 45 psec for the substitutional H^- local mode, and a more rapid relaxation for the interstitial H^- local modes next to La^3+ and Lu^3+ impurities. Information on the decay channels of the local modes are obtained from the characteristic temperature dependence of the relaxation rates. This work is supported in part by the ONR, Grant No. N00014-94-1024.

  20. Scintillation Response of CaF2 to H and He over a Continuous Energy Range

    International Nuclear Information System (INIS)

    Zhang, Yanwen; Xiang, Xia; Weber, William J.

    2008-01-01

    Recent demands for new radiation detector materials with improved γ-ray detection performance at room temperature have prompted research efforts on both accelerated material discovery and efficient techniques that can be used to identify material properties relevant to detector performance. New material discovery has been limited due to the difficulties of large crystal growth to completely absorb γ-energies; whereas high-quality thin films or small crystals of candidate materials can be readily produced by various modern growth techniques. In this work, an ion-scintillator technique is demonstrated that can be applied to study scintillation properties of thin films and small crystals. The scintillation response of a benchmark scintillator, europium-doped calcium fluoride (CaF2:Eu), to energetic proton and helium ions is studied using the ion-scintillator approach based on a time of flight (TOF) telescope. Excellent energy resolution and fast response of the TOF telescope allow quantitative measurement of light yield, nonlinearity and energy resolution over an energy range from a few tens to a few thousands of keV

  1. Nanocolloidal Ru/MgF2 Catalyst for Hydrogenation of Chloronitrobenzene and Toluene

    Directory of Open Access Journals (Sweden)

    Pietrowski Mariusz

    2014-06-01

    Full Text Available The use of magnesium fluoride support for ruthenium active phase allowed obtaining new catalysts of high activities in the hydrogenation of toluene and ortho-chloronitrobenzene. Ruthenium colloid catalysts (1 wt.% of Ru were prepared by impregnation of the support with the earlier produced polyvinylpyrrolidone (PVP-stabilized ruthenium colloids. The performances of the colloidal catalysts and those obtained by traditional impregnation were tested in the reactions of toluene hydrogenation to methylcyclohexane and selective hydrogenation of ortho-chloronitrobenzene (o-CNB to ortho-chloroaniline (o-CAN. It was shown that the use of chemical reduction method allows obtaining highly monodisperse ruthenium nanoparticles of 1.6–2.6 nm in size. After reduction in hydrogen at 400oC, the colloidal ruthenium nanoparticles were found to strongly interact with MgF2 surface (SMSI, which decreased the catalyst ability to hydrogen chemisorption, but despite this, the colloid catalysts showed higher activity in o-CNB hydrogenation and higher selectivity to o-CAN than the traditional ones. It is supposed that their higher activity can be a result of high dispersion of Ru in colloid catalysts and the higher selectivity can be a consequence of the lower availability of hydrogen on the surface.

  2. Mellin moments of heavy flavor contributions to F2(x,Q2) at NNLO

    International Nuclear Information System (INIS)

    Klein, Sebastian Werner Gerhard

    2009-10-01

    The main parts of this thesis are the extension of the description of the contributions of heavy quark mass-effects to the deep-inelastic Wilson coefficients to NNLO. In course of that, we also obtain a first independent calculation of fixed moments of the fermionic parts of the NNLO anomalous dimensions. The calculation of the 3-loop heavy flavor Wilson coefficients in the whole Q 2 region is currently not within reach. However, a very precise description of the heavy flavor Wilson coefficients contributing to the structure function F 2 (x,Q 2 ) at NLO is obtained for Q 2 >or similar 10 m Q 2 , disregarding the power corrections ∝(m Q 2 /Q 2 ) k , k ≥ 1. If one considers the charm quark, this covers an important region for deep-inelastic physics at HERA. In this limit, the massive Wilson coefficients factorize into universal massive operator matrix elements (OMEs) A ij (x, μ 2 /m Q 2 ) and the light flavor Wilson coefficients C (q,g),(2,L) (x,Q 2 /μ 2 ). The former are process independent quantities and describe all quark mass effects. They are given by matrix elements of the leading twist local composite operators O i between partonic states j (i, j = q, g), including quark masses. The process dependence is described by the massless Wilson coefficients. (orig.)

  3. Crosshole investigations - physical properties of core samples from boreholes F1 and F2

    International Nuclear Information System (INIS)

    Magnusson, K.A.; Carlsten, S.; Olsson, O.

    1987-06-01

    The geology and physical properties have been studied of roughly 100 core samples from the boreholes F1 and F2 drilled at the Crosshole site, located at the 360 m level in the Stripa mine. The granitic rock has been divided into two classes: Fracture zones (also called major units) and a rock mass which is relatively undeformed. Samples from the major units have lower resistivity, higher porosity and dielectric constant than the samples from the less deformed rock mass. The electrical properties of the core samples have been measured over a frequency interval ranging from 1 Hz to 70 MHz. The conductivity of the samples increases with frequency, approximately with the frequency raised to the power 0.38. The dielectric constant decreases with frequency but is essentially constant above 3 MHz. These results show that the Hanai-Bruggeman equation can be used to describe the electrical bulk properties of the Stripa granite. The electrical conductivity of the samples is well correlated to the water content of the samples. The granite has a small contents of electrically conductive minerals which could influence the electrical bulk properties. (orig.)

  4. Absorption Spectra of BaF2 Sm2O3, Sm, Gd, and Ho Plasmas

    Science.gov (United States)

    Martin, Michael; Bastiani-Ceccotti, Serena

    2009-11-01

    Knowledge of the opacities of high Z element plasmas is important in indirect drive ICF and the study of stellar evolution. There are few experimental measurements of this quantity, and its theoretical determination is difficult due to the number of possible bound electron configurations. This study aims to better the theoretical understanding of this parameter by looking at the 3d-4f transitions of BaF2, Sm2O3, Sm, Gd, and Ho plasmas at the LULI2000 facility. The plasmas are produced by radiative heating and are cold, 15 -- 40 eV, and relatively dense, ˜ .01gm/cm^3 A plasma is produced by a .5 ns laser pulse irradiating a gold hohlraum and then probed by an x-ray source created by a gold foil irradiated by a 10 ps laser pulse. The transmission is found with simultaneous source and absorption measurements by an x-ray spectrometer in the 8 - 20 å range We will compare the results with statistical atomic structure codes. From this experiment we will gain further insight into the spectral broadening of neighboring Z elements due to changing plasma temperature and into mixture thermodynamics. This is a first step towards an experimental study of astrophysical domains.

  5. Parameters of heavy quark effective theory from N{sub f}=2 lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Blossier, Benoit [CNRS, Orsay (France). LPT; Paris-11 Univ., 91 - Orsay (France); Della Morte, Michele [Mainz Univ. (Germany). Inst. fuer Kernphysik; Fritzsch, Patrick [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Garron, Nicolas [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Heitger, Jochen [Muenster Univ. (Germany). Inst. fuer Theoretische Physik 1; Simma, Hubert; Sommer, Rainer [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Tantalo, Nazario [Rome-3 Univ. (Italy). Dipt. di Fisica; INFN, Sezione di Roma (Italy)

    2012-07-15

    We report on a non-perturbative determination of the parameters of the lattice Heavy Quark Effective Theory (HQET) Lagrangian and of the time component of the heavy-light axial-vector current with N{sub f} = 2 flavors of massless dynamical quarks. The effective theory is considered at the 1/m{sub h} order, and the heavy mass m{sub h} covers a range from slightly above the charm to beyond the beauty region. These HQET parameters are needed to compute, for example, the b-quark mass, the heavy-light spectrum and decay constants in the static approximation and to order 1/m{sub h} in HQET. The determination of the parameters is done non-perturbatively. The computation reported in this paper uses the plaquette gauge action and two different static actions for the heavy quark described by HQET. For the light-quark action we choose non-perturbatively O(a)-improved Wilson fermions.

  6. Pyometra in Bitches Induces Elevated Plasma Endotoxin and Prostaglandin F2α Metabolite Levels

    Directory of Open Access Journals (Sweden)

    Hagman R

    2006-03-01

    Full Text Available Endotoxemia in bitches with pyometra can cause severe systemic effects directly or via the release of inflammatory mediators. Plasma endotoxin concentrations were measured in ten bitches suffering from pyometra with moderately to severely deteriorated general condition, and in nine bitches admitted to surgery for non-infectious reasons. Endotoxin samples were taken on five occasions before, during and after surgery. In addition, urine and uterine bacteriology was performed and hematological, blood biochemical parameters, prostaglandin F2α metabolite 15-ketodihydro-PGF2α (PG-metabolite, progesterone and oestradiol (E2-17β levels were analysed. The results confirm significantly increased plasma levels of endotoxin in bitches with pyometra and support previous reports of endotoxin involvement in the pathogenesis of the disease. Plasma concentrations of PG-metabolite were elevated in pyometra bitches and provide a good indicator of endotoxin release since the concentrations were significantly correlated to the endotoxin levels and many other hematological and chemistry parameters. The γ-globulin serum protein electrophoresis fraction and analysis of PG-metabolite can be valuable in the diagnosis of endotoxin involvement if a reliable, rapid and cost-effective test for PG-metabolite analysis becomes readily available in the future. Treatment inhibiting prostaglandin biosynthesis and related compounds could be beneficial for bitches suffering from pyometra.

  7. Magnon dispersion relation and exchange interactions in MnF2

    DEFF Research Database (Denmark)

    Nikotin, O.; Lindgård, Per-Anker; Dietrich, O. W.

    1969-01-01

    The magnon dispersion relation for MnF2 at 4·2 °K has been measured by means of the triple-axis neutron scattering technique along the symmetry lines in the (010) plane of the Brillouin zone. Using an exact dipole model, the three nearest-neighbour exchange constants were found to be J1 = 0·028 ± 0......·001 mev, J2 = -0·152 ± 0·001 mev and J3 = -0·004 ± 0·001 mev. The second moment was also calculated with this model. The density of magnon states was evaluated by applying a six-parameter simulation of the dispersion surface. The critical points in the density of states agree well with those obtained...... by optical double-magnon experiments, whereas the detailed shape of the density of states differs significantly, indicating that the effect of magnon-magnon interactions rather than that of distant-neighbour exchange is of primary importance in the optical measurements....

  8. Synthesis and dosimetric characterization of LiF-MgF2, doped with Lu

    International Nuclear Information System (INIS)

    Gonzalez, Pedro R.; Nieto, Ana L.; Cruz-Zaragoza, Epifanio; Furetta, Claudio

    2013-01-01

    The results of the synthesis and characterization of dosimetric thermoluminescent material based on the composition LiF-MgF 2 1:1 (Z eff = 9.7) doped Lu 3+ ions, developed at the National Institute of Nuclear Research, Mexico are presented. The TL material synthesis was carried out using the technique of casting solid substances, preparations were made with dopant concentrations of 0.25, 0.83, 1.00 and 2.00 mol%, the 1 mol% resulted in increased sensitivity to radiation. Its brightness curve has the TL peak intensity at 330 deg C when irradiated to 1000 Gy, whereas when irradiated greater than 2500 Gy, occurs at 230 ° C, also has a peak of smaller maximum intensity at 140 ° C. Microstructural characterization of the obtained material was performed using the techniques of scanning electron microscopy and X-ray diffraction Kinetic parameters of the curves of brightness of the material is performed by the deconvolution method using the sequential quadratic programming algorithm, developed in the same institute. This new TL material complies fully with international standards to be used as dosimetry system in medical physics, research and industry, as its TL response (total integrated under the curve) to 60 Co gamma radiation, presents linearity between 1 and 5000 Gy , while the response of commercial TLD dosimeter-100 used as a reference, is only linear up to 10 Gy

  9. KIMA, PERLUKAH MENUNGGU F2 UNTUK PERDAGANGAN? SUATU KAJIAN BERDASARKAN MARKER GENETIK

    Directory of Open Access Journals (Sweden)

    Estu Nugroho

    2008-12-01

    Full Text Available Kima (Tridagnidae merupakan salah satu komoditas air laut yang prospektif secara ekonomis, tercatat harga di Taiwan adalah $35--$142 per kg. Dalam pengembangan akuabisnis kima masih dijumpai kendala di antaranya adalah adanya aturan bahwa hanya turunan kedua atau F2 yang boleh diperdagangkan karena masuk dalam daftar CITES (Convention on Trade of Endangered Species menurut PP No. 8 tahun 1999 tentang pemanfaatan satwa. Karena pertumbuhannya yang relatif lambat serta adanya negara lain, misalnya Filipina, Fiji, dan Taiwan yang memperdagangkan hasil budidaya pada turunan F1, maka keadaan ini sangat merugikan pihak Indonesia. Kajian tentang permasalahan penurunan variasi genetik merupakan salah satu alternatif untuk mendukung adanya pelonggaran persyaratan perdagangan kima tersebut. Kajian genetika dengan menggunakan marker genetik menunjukkan bahwa tidak terjadi penurunan variasi genetik seperti yang dikuatirkan sebelumnya. Keragaman genetik pada F1 meningkat dibandingkan dengan induknya, yaitu 0,073 dan 0,023. Jarak genetik antar populasi yang diuji adalah sebesar 0,016.

  10. Placental Origin of Prostaglandin F2α in the Domestic Cat

    Directory of Open Access Journals (Sweden)

    Marta J. Siemieniuch

    2014-01-01

    Full Text Available In the present study, the question was addressed whether the feline placenta can synthesize prostaglandin F2α (PGF2α. The PGFS protein was elevated, particularly at 2.5–3 weeks of pregnancy compared to 7-8 (P<0.05 and 8.5–9 weeks (P<0.001. Transcripts for PGFS were significantly upregulated at 2.5–3 weeks of pregnancy and then gradually declined towards the end of gestation (P<0.001. Transcripts for PTGS2 were only upregulated in placentas from queens close to term (P<0.001 compared with earlier phases. Staining of PTGS2 showed distinct positive signals in placentas obtained during the last week before labor, particularly in the strongly invading trophoblast surrounding blood vessels, and also in decidual cells. Shortly after implantation, signals for PGFS were localized in the trophoblast cells. Near term, PGFS staining was seen mainly in decidual cells. Both placental PGF2α and plasma PGFM were elevated towards the end of pregnancy (P<0.001 compared with earlier weeks of pregnancy. The content of PGF2α in extracted placenta mirrored the PGFM level in plasma of pregnant females. During late gestation there is a significant increase in PGFM levels in maternal blood and of PGF2α levels in placental tissue concomitant with an upregulation of placental PTGS2.

  11. Longitudinal conductivity of LaF3/SrF2 multilayer heterostructures.

    Science.gov (United States)

    Vergentev, Tikhon; Banshchikov, Alexander; Filimonov, Alexey; Koroleva, Ekaterina; Sokolov, Nikolay; Wurz, Marc Christopher

    2016-01-01

    LaF 3 /SrF 2 multilayer heterostructures with thicknesses of individual layers in the range 5-100 nm have been grown on MgO(100) substrates using molecular beam epitaxy. The longitudinal conductivity of the films has been measured using impedance spectroscopy in the frequency range 10 -1 -10 6  Hz and a temperature range 300-570 K. The ionic DC conductivities have been determined from Nyquist impedance diagrams and activation energies from the Arrhenius-Frenkel equation. An increase of the DC conductivity has been observed to accompany decreased layer thickness for various thicknesses as small as 25 nm. The greatest conductivity has been shown for a multilayer heterostructure having thicknesses of 25 nm per layer. The structure has a conductivity two orders of magnitude greater than pure LaF 3 bulk material. The increasing conductivity can be understood as a redistribution of charge carriers through the interface due to differing chemical potentials of the materials, by strong lattice-constant mismatch, and/or by formation of a solid La 1-x Sr x F 3-x solution at the interface during the growth process.

  12. Measurement of the Charm structure Function $F_{2}^{\\gamma},c$ of the Photon at LEP

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Amaral, P.; Anagnostou, G.; Anderson, K.J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Barberio, E.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Bloodworth, I.J.; Boeriu, O.; Bock, P.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Busser, K.; Burckhart, H.J.; Cammin, J.; Campana, S.; Carnegie, R.K.; Caron, B.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Cohen, I.; Csilling, A.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; de Roeck, A.; De Wolf, E.A.; Desch, K.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Elfgren, E.; Etzion, E.; Fabbri, F.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Furtjes, A.; Gagnon, P.; Gary, John William; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harder, K.; Harel, A.; Harin-Dirac, M.; Hauschild, M.; Hauschildt, J.; Hawkings, R.; Hemingway, R.J.; Hensel, C.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Homer, R.J.; Horvath, D.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klein, K.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Komamiya, S.; Kormos, Laura L.; Kowalewski, Robert V.; Kramer, T.; Kress, T.; Krieger, P.; Von Krogh, J.; Krop, D.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Layter, J.G.; Leins, A.; Lellouch, D.; Letts, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, J.; Macpherson, A.; Mader, W.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Masetti, G.; Mashimo, T.; Mattig, Peter; McDonald, W.J.; McKenna, J.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Menges, W.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Moed, S.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Rick, H.; Roney, J.M.; Rosati, S.; Rozen, Y.; Runge, K.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sarkisian, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schoerner-Sadenius, Thomas; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Spano, F.; Stahl, A.; Stephens, K.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Taylor, R.J.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trefzger, T.; Tricoli, A.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vachon, B.; Vollmer, C.F.; Vannerem, P.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.; Zivkovic, Lidija

    2002-01-01

    The production of charm quarks is studied in deep-inelastic electron-photon scattering using data recorded by the OPAL detector at LEP at normal e+e- centre-of-mass energies from 183 to 209 GeV. The charm quarks have been identified by full reconstruction of charged D* mesons using their decays into D0pi with the D0 observed in two decay modes with charged particle final states, Kpi and K3pi. The cross-section sigma(D*) for production of charged D* in the reaction e+e- -> e+e-D*X is measured in a restricted kinematical region using two bins in Bjorken x, 0.0014 e+e- ccbar X) and the charm structure function of the photon F 2,c are determined in the region 0.0014 0.1 the perturbative QCD calculation at next-to-leading order agrees perfectly with the measured cross-section. For x < 0.1 the measured cross-section is 43.8 +- 14.3 +- 6.3 +- 2.8 pb with a next-to-leading order prediction of 17.0+2.9-2.3 p.b.

  13. Plasma 8-iso-Prostaglandin F2α, a possible prognostic marker in aneurysmal subarachnoid hemorrhage.

    Science.gov (United States)

    Pan, De-Sheng; Yan, Min; Hassan, Muhammad; Fang, Ze-Bin; Chen, Man-Tao

    2017-06-01

    8-iso-Prostaglandin F2α (8-iso-PGF2α) is a potential biomarker of oxidative stress. This study clarified whether plasma 8-iso-PGF2α concentrations were affected and its underlying relevance to prognosis in aneurysmal subarachnoid hemorrhage (aSAH). In this prospective, observational study, a total of 170 controls and 170 aSAH patients were enrolled. Plasma 8-iso-PGF2α concentrations were detected using an ELISA. Severity was assessed by World Federation of Neurological Surgeons (WFNS) scale and modified Fisher grading scale. Clinical outcomes included 6-month mortality and poor outcome referred to as Glasgow outcome scale score of 1-3. As compared to controls, admission plasma 8-iso-PGF2α concentrations were significantly enhanced. Increased concentrations of plasma 8-iso-PGF2α correlated with WFNS scores and modified Fisher scores. 8-iso-PGF2α in plasma was an independent predictor for clinical outcomes. Under ROC curve, the predictive values of 8-iso-PGF2α concentrations resembled those of WFNS scores and modified Fisher scores for clinical outcomes. An elevation in plasma 8-iso-PGF2α concentrations is associated with the severity and poor outcome after aSAH, substantializing 8-iso-PGF2α as a potential prognostic biomarker of aSAH. Copyright © 2017. Published by Elsevier B.V.

  14. Evolution of the spectrum of the solvated electron in BeF2 aqueous glasses at 76 K

    International Nuclear Information System (INIS)

    Nguyen, T.Q.; Walker, D.C.; Gillis, H.A.

    1978-01-01

    Evidence is presented for a spontaneous shift from infrared-to- red-to-green in the overall spectrum of the electron trapped in an aqueous glass at 76 K following nanosecond pulse radiolysis. As with the alcohols, after the pulse the infrared absorption decays, there is a growth-then-decay of absorbance at intermediate wavelengths and net growth of absorption due to the equilibrated trapped electron state, e - /sub vis/. This progressive transition was not characterised by a single-step process and was discernible in aqueous glasses containing 7.5 or 10.7M BeF 2 in D 2 O. At higher BeF 2 concentrations, or with LiBr as glass-forming electrolyte, no growth of e - /sub vis/ was observed, probably because of concurrent loss of e - /sub vis/ in those glasses, as in LiCl and other glasses. BeF 2 glasses of trapped electrons showed several other features of interest: (i) wavelength- selective bleaching of the e - /sub vis/ band indicates that it is composed of a broad ''green'' band (lambda/sub max/, 530--590 nm) which bleaches homogeneously, and a broad ''red'' region which bleaches inhomogeneously. (ii) lambda/sub max/ for e - /sub vis/ changes with BeF 2 concentration, being blue shifted with increasing concentration , with both green and red underlying structures shifting slightly. (iii) No absorption due to F - 2 was found following pulse radiolysis in these glasses at 76 K. (iv) Several recent findings with LiCl are mimicked by F - 2 glasses. For instance, G (e - /sub vis/) increases and G (e - /sub ir/) decreases as the electrolyte concentration is increased, while the combined yield remains constant at 1.8 +- 0.1

  15. A prediction model of short-term ionospheric foF2 based on AdaBoost

    Science.gov (United States)

    Zhao, Xiukuan; Ning, Baiqi; Liu, Libo; Song, Gangbing

    2014-02-01

    In this paper, the AdaBoost-BP algorithm is used to construct a new model to predict the critical frequency of the ionospheric F2-layer (foF2) one hour ahead. Different indices were used to characterize ionospheric diurnal and seasonal variations and their dependence on solar and geomagnetic activity. These indices, together with the current observed foF2 value, were input into the prediction model and the foF2 value at one hour ahead was output. We analyzed twenty-two years' foF2 data from nine ionosonde stations in the East-Asian sector in this work. The first eleven years' data were used as a training dataset and the second eleven years' data were used as a testing dataset. The results show that the performance of AdaBoost-BP is better than those of BP Neural Network (BPNN), Support Vector Regression (SVR) and the IRI model. For example, the AdaBoost-BP prediction absolute error of foF2 at Irkutsk station (a middle latitude station) is 0.32 MHz, which is better than 0.34 MHz from BPNN, 0.35 MHz from SVR and also significantly outperforms the IRI model whose absolute error is 0.64 MHz. Meanwhile, AdaBoost-BP prediction absolute error at Taipei station from the low latitude is 0.78 MHz, which is better than 0.81 MHz from BPNN, 0.81 MHz from SVR and 1.37 MHz from the IRI model. Finally, the variety characteristics of the AdaBoost-BP prediction error along with seasonal variation, solar activity and latitude variation were also discussed in the paper.

  16. Inner ear dysfunction in caspase-3 deficient mice

    Directory of Open Access Journals (Sweden)

    Woo Minna

    2011-10-01

    Full Text Available Abstract Background Caspase-3 is one of the most downstream enzymes activated in the apoptotic pathway. In caspase-3 deficient mice, loss of cochlear hair cells and spiral ganglion cells coincide closely with hearing loss. In contrast with the auditory system, details of the vestibular phenotype have not been characterized. Here we report the vestibular phenotype and inner ear anatomy in the caspase-3 deficient (Casp3-/- mouse strain. Results Average ABR thresholds of Casp3-/- mice were significantly elevated (P Casp3+/- mice and Casp3+/+ mice at 3 months of age. In DPOAE testing, distortion product 2F1-F2 was significantly decreased (P Casp3-/- mice, whereas Casp3+/- and Casp3+/+ mice showed normal and comparable values to each other. Casp3-/- mice were hyperactive and exhibited circling behavior when excited. In lateral canal VOR testing, Casp3-/- mice had minimal response to any of the stimuli tested, whereas Casp3+/- mice had an intermediate response compared to Casp3+/+ mice. Inner ear anatomical and histological analysis revealed gross hypomorphism of the vestibular organs, in which the main site was the anterior semicircular canal. Hair cell numbers in the anterior- and lateral crista, and utricle were significantly smaller in Casp3-/- mice whereas the Casp3+/- and Casp3+/+ mice had normal hair cell numbers. Conclusions These results indicate that caspase-3 is essential for correct functioning of the cochlea as well as normal development and function of the vestibule.

  17. EVALUASI KERAGAMAN GENETIK INDUK IKAN KERAPU SUNU (Plectropomus leopardus F-1 DAN TURUNANNYA (F-2 DENGAN PENANDA mt-DNA

    Directory of Open Access Journals (Sweden)

    Sari Budi Moria Sembiring

    2012-12-01

    pada turunannya (F-2. Hal ini dimungkinkan bahwa yuwana yang dianalisis tersebut berasal dari populasi 3 komposit haplotip induk F-1. Hasil analisis dengan program Tools for Population Genetic Analysis (TFPGA menunjukkan bahwa nilai keragaman genetik induk F-1 mengalami penurunan sebesar 20,46% terhadap turunannya (F-2, hal ini diduga karena sedikitnya jumlah induk efektif yang memijah. Dengan demikian penambahan induk efektif perlu dilakukan untuk menghindari laju penurunan keragaman genetik.

  18. Gold-coated copper cone detector as a new standard detector for F2 laser radiation at 157 nm

    International Nuclear Information System (INIS)

    Kueck, Stefan; Brandt, Friedhelm; Taddeo, Mario

    2005-01-01

    A new standard detector for high-accuracy measurements of F2 laser radiation at 157 nm is presented. This gold-coated copper cone detector permits the measurement of average powers up to 2 W with an uncertainty of ∼1%. To the best of our knowledge, this is the first highly accurate standard detector for F2 laser radiation for this power level. It is fully characterized according to Guide to the Expression of Uncertainty in Measurement of the International Organization for Standardization and is connected to the calibration chain for laser radiation established by the German National Metrology Institute

  19. Next-to-leading order strong interaction corrections to the ΔF = 2 effective Hamiltonian in the MSSM

    International Nuclear Information System (INIS)

    Ciuchini, Marco; Franco, E.; Guadagnoli, D.; Lubicz, Vittorio; Porretti, V.; Silvestrini, L.

    2006-01-01

    We compute the next-to-leading order strong interaction corrections to gluino-mediated ΔF = 2 box diagrams in the Minimal Supersymmetric Standard Model. These corrections are given by two loop diagrams which we have calculated in three different regularization schemes in the mass insertion approximation. We obtain the next-to-leading order Wilson coefficients of the ΔF = 2 effective Hamiltonian relevant for neutral meson mixings. We find that the matching scale uncertainty is largely reduced at the next-to-leading order, typically from about 10-15% to few percent

  20. Changes in oil composition after chronic irradiation of winter and spring zero-erucic rape hybrids

    International Nuclear Information System (INIS)

    Fabry, A.; Cerny, J.

    1980-01-01

    Hybrid plants of the F1 generation of erucic-free spring Canadian rape and some winter rape cultivars containing erucic acid were irradiated in a gamma field with doses ranging between 5973 and 329 R during vegetation. Chronic irradiation increased significantly the frequency of zero- or low-erucic genotypes in the segregating F2 generation. Chronic irradiation disturbed the correlations between the contents of the studied fatty acids in the hybrid F1, F2 and F3 progenies. Lines of zero- and low-erucic winter rapes with a reduced content of linolenic acid and increased content of linoleic acid were obtained by selection. (author)

  1. New facilities for Al+MgF2 coating for 2-m class mirrors for UV

    Science.gov (United States)

    Zhupanov, Valery; Vlasenko, Oleg; Sachkov, Mikhail; Fedoseev, Viktor

    2014-07-01

    above 120 nm [19] with reflectivity more than 90% at wavelength longer than 200 nm, but the spectral range from 700 to 900 nm, where it's lowest value of reflectivity is 86% at 850 nm. That makes aluminum one of the best coating materials in the creating a mirror for operations in vacuum ultraviolet. However, the aluminum membrane is prone to oxidization, so applying the protecting coating is essential. Magnesium fluoride is one of the few materials transparent in the UV range [20]. In this contribution, capacities of new facilities in LUCH company that are created for World Space Observatory - Ultraviolet (WSO-UV) project are described in Section 2, the process of applying Al + MgF2 coating workout is presented in Section 3, results of applying Al+MgF2 coating for WSO-UV primary mirror are presented in Section 4 and a brief summary are provided in the concluding Section 5.

  2. Craniomandibular form and body size variation of first generation mouse hybrids: A model for hominin hybridization.

    Science.gov (United States)

    Warren, Kerryn A; Ritzman, Terrence B; Humphreys, Robyn A; Percival, Christopher J; Hallgrímsson, Benedikt; Ackermann, Rebecca Rogers

    2018-03-01

    Hybridization occurs in a number of mammalian lineages, including among primate taxa. Analyses of ancient genomes have shown that hybridization between our lineage and other archaic hominins in Eurasia occurred numerous times in the past. However, we still have limited empirical data on what a hybrid skeleton looks like, or how to spot patterns of hybridization among fossils for which there are no genetic data. Here we use experimental mouse models to supplement previous studies of primates. We characterize size and shape variation in the cranium and mandible of three wild-derived inbred mouse strains and their first generation (F 1 ) hybrids. The three parent taxa in our analysis represent lineages that diverged over approximately the same period as the human/Neanderthal/Denisovan lineages and their hybrids are variably successful in the wild. Comparisons of body size, as quantified by long bone measurements, are also presented to determine whether the identified phenotypic effects of hybridization are localized to the cranium or represent overall body size changes. The results indicate that hybrid cranial and mandibular sizes, as well as limb length, exceed that of the parent taxa in all cases. All three F 1 hybrid crosses display similar patterns of size and form variation. These results are generally consistent with earlier studies on primates and other mammals, suggesting that the effects of hybridization may be similar across very different scenarios of hybridization, including different levels of hybrid fitness. This paper serves to supplement previous studies aimed at identifying F 1 hybrids in the fossil record and to introduce further research that will explore hybrid morphologies using mice as a proxy for better understanding hybridization in the hominin fossil record. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Epistatic Effects Contribute to Variation in BMD in Fischer 344 × Lewis F2 Rats

    Science.gov (United States)

    Koller, Daniel L; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J; Foroud, Tatiana; Turner, Charles H

    2008-01-01

    To further delineate the factors underlying the complex genetic architecture of BMD in the rat model, a genome screen for epistatic interactions was conducted. Several significant interactions were identified, involving both previously identified and novel QTLs. Introduction The variation in several of the risk factors for osteoporotic fracture, including BMD, has been shown to be caused largely by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We have previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 595 female F2 progeny of Fischer 344 and Lewis rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Materials and Methods Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted BMD (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine a genome-wide significance threshold for the epistasis or interaction LOD score corresponding to an α level of 0.01. Results and Conclusions Novel loci on chromosomes 12 and 15 showed a strong epistatic effect on total BMD at the femoral midshaft by pQCT (LOD = 5.4). A previously reported QTL on chromosome 7 was found to interact with a novel locus on chromosome 20 to affect whole lumbar BMD by pQCT (LOD = 6.2). These results provide new information regarding the mode of action of previously identified rat QTLs, as well as identifying novel loci that act in combination with known QTLs or with other novel loci to contribute to the risk factors for osteoporotic fracture. PMID:17907919

  4. Epistatic effects contribute to variation in BMD in Fischer 344 x Lewis F2 rats.

    Science.gov (United States)

    Koller, Daniel L; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J; Foroud, Tatiana; Turner, Charles H

    2008-01-01

    To further delineate the factors underlying the complex genetic architecture of BMD in the rat model, a genome screen for epistatic interactions was conducted. Several significant interactions were identified, involving both previously identified and novel QTLs. The variation in several of the risk factors for osteoporotic fracture, including BMD, has been shown to be caused largely by genetic differences. However, the genetic architecture of BMD is complex in both humans and in model organisms. We have previously reported quantitative trait locus (QTL) results for BMD from a genome screen of 595 female F(2) progeny of Fischer 344 and Lewis rats. These progeny also provide an excellent opportunity to search for epistatic effects, or interaction between genetic loci, that contribute to fracture risk. Microsatellite marker data from a 20-cM genome screen was analyzed along with weight-adjusted BMD (DXA and pQCT) phenotypic data using the R/qtl software package. Genotype and phenotype data were permuted to determine a genome-wide significance threshold for the epistasis or interaction LOD score corresponding to an alpha level of 0.01. Novel loci on chromosomes 12 and 15 showed a strong epistatic effect on total BMD at the femoral midshaft by pQCT (LOD = 5.4). A previously reported QTL on chromosome 7 was found to interact with a novel locus on chromosome 20 to affect whole lumbar BMD by pQCT (LOD = 6.2). These results provide new information regarding the mode of action of previously identified rat QTLs, as well as identifying novel loci that act in combination with known QTLs or with other novel loci to contribute to the risk factors for osteoporotic fracture.

  5. Neutron electric dipole moment using N{sub f}=2+1+1 twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrou, C.; Athenodorou, A.; Constantinou, M.; Hadjiyiannakou, K. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; The Cyprus Institute, Nicosia (Cyprus). Computation-based Science and Technology Research Center; Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Koutsou, G. [The Cyprus Institute, Nicosia (Cyprus). Computation-based Science and Technology Research Center; Ottnad, K. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Bonn Univ. (Germany). Helmholtz-Institut fuer Strahlen- und Kernphysik; Bonn Univ. (Germany). Bethe Center for Theoretical Physics; Petschlies, M. [The Cyprus Institute, Nicosia (Cyprus). Computation-based Science and Technology Research Center; Bonn Univ. (Germany). Helmholtz-Institut fuer Strahlen- und Kernphysik; Bonn Univ. (Germany). Bethe Center for Theoretical Physics

    2016-03-15

    We evaluate the neutron electric dipole moment vertical stroke vector d{sub N} vertical stroke using lattice QCD techniques. The gauge configurations analyzed are produced by the European Twisted Mass Collaboration using N{sub f}=2+1+1 twisted mass fermions at one value of the lattice spacing of a ≅0.082 fm and a light quark mass corresponding to m{sub π}≅373 MeV. Our approach to extract the neutron electric dipole moment is based on the calculation of the CP-odd electromagnetic form factor F{sub 3}(Q{sup 2}) for small values of the vacuum angle θ in the limit of zero Euclidean momentum transfer Q{sup 2}. The limit Q{sup 2}→0 is realized either by adopting a parameterization of the momentum dependence of F{sub 3}(Q{sup 2}) and performing a fit, or by employing new position space methods, which involve the elimination of the kinematical momentum factor in front of F{sub 3}(Q{sup 2}). The computation in the presence of a CP-violating term requires the evaluation of the topological charge Q. This is computed by applying the cooling technique and the gradient flow with three different actions, namely the Wilson, the Symanzik tree-level improved and the Iwasaki action. We demonstrate that cooling and gradient flow give equivalent results for the neutron electric dipole moment. Our analysis yields a value of vertical stroke vector d{sub N} vertical stroke =0.045(6)(1) anti θ e.fm for the ensemble with m{sub π}=373 MeV considered.

  6. Stringent tests of constrained Minimal Flavor Violation through {Delta}F=2 transitions

    Energy Technology Data Exchange (ETDEWEB)

    Buras, Andrzej J. [TUM-IAS, Garching (Germany); Girrbach, Jennifer [TUM, Physik Department, Garching (Germany)

    2013-09-15

    New Physics contributions to {Delta}F=2 transitions in the simplest extensions of the Standard Model (SM), the models with constrained Minimal Flavor Violation (CMFV), are parametrized by a single variable S(v), the value of the real box diagram function that in CMFV is bounded from below by its SM value S{sub 0}(x{sub t}). With already very precise experimental values of {epsilon}{sub K}, {Delta}M{sub d}, {Delta}M{sub s} and precise values of the CP-asymmetry S{sub {psi}K{sub S}} and of B{sub K} entering the evaluation of {epsilon}{sub K}, the future of CMFV in the {Delta}F = 2 sector depends crucially on the values of vertical stroke V{sub cb} vertical stroke, vertical stroke V{sub ub} vertical stroke, {gamma}, F{sub B{sub s}} {radical}(B{sub B{sub s}}) and F{sub B{sub d}} {radical}(B{sub B{sub d}}). The ratio {xi} of the latter two non-perturbative parameters, already rather precisely determined from lattice calculations, allows then together with {Delta}M{sub s} / {Delta}M{sub d} and S{sub {psi}K{sub S}} to determine the range of the angle {gamma} in the unitarity triangle independently of the value of S(v). Imposing in addition the constraints from vertical stroke {epsilon}{sub K} vertical stroke and {Delta}M{sub d} allows to determine the favorite CMFV values of vertical stroke V{sub cb} vertical stroke, vertical stroke V{sub ub} vertical stroke, F{sub B{sub s}} {radical}(B{sub B{sub s}}) and F{sub B{sub d}} {radical}(B{sub B{sub d}}) as functions of S(v) and {gamma}. The vertical stroke V{sub cb} vertical stroke {sup 4} dependence of {epsilon}{sub K} allows to determine vertical stroke V{sub cb} vertical stroke for a given S(v) and {gamma} with a higher precision than it is presently possible using tree-level decays. The same applies to vertical stroke V{sub ub} vertical stroke, vertical stroke V{sub td} vertical stroke and vertical stroke V{sub ts} vertical stroke that are automatically determined as functions of S(v) and {gamma}. We derive correlations

  7. Effect of preterm formula with and without long-chain polyunsaturated fatty acids on the urinary excretion of F2-isoprostanes and 8-epi-prostaglandin F2alpha.

    Science.gov (United States)

    Stier, C; Schweer, H; Jelinek, J; Watzer, B; Seyberth, H W; Leonhardt, A

    2001-02-01

    The objective of this study was to evaluate the effect of conventional and long-chain polyunsaturated fatty acids (LCP)-enriched preterm formula on the endogenous formation of F2-isoprostanes and 8-epi-prostaglandin (PG) F2alpha as possible markers of lipid peroxidation in preterm infants during their first weeks of life. In a prospective, randomized, double-blind study, infants received either formula enriched with LCP (n = 8), standard preterm formula (n = 7), or (expressed) breast milk (n = 8). Urine was sampled at study entry and after the study period of 3 weeks. The formation of F2-isoprostanes and 8-epi-PGF2alpha was evaluated by measuring the urinary excretion by gas chromatography-mass spectrometry. No differences in the urinary excretion of F2-isoprostanes and 8-epi-PGF2alpha were observed at the end of the study period. This result suggests that supplementation of a preterm formula with LCP for a period of 3 weeks does not stimulate lipid peroxidation in preterm infants.

  8. THE THERMODYNAMIC PROPERTIES OF MELTS OF DOUBLE SYSTEM MgO – Al2O3, MgO – SiO2, MgO – CaF2, Al2O3 – SiO2, Al2O3 – CaF2, SiO2 – CaF2

    Directory of Open Access Journals (Sweden)

    В. Судавцова

    2012-04-01

    Full Text Available Methodology of prognostication of thermodynamics properties of melts is presented from the coordinatesof liquidus of diagram of the state in area of equilibria a hard component is solution, on which energies ofmixing of Gibbs are expected in the double border systems of MgO – Al2O3, MgO – SiO2, MgO – CaF2,Al2O3 – SiO2, Al2O3 - CaF2, SiO2 - CaF2. For the areas of equilibrium there is quasibinary connection(MgAl2O4, Mg2SiO4, Al6Si2O13 – a grout at calculations was used equalization of Hauffe-Wagner. Theobtained data comport with literary

  9. NMR metabolomics of thrips (Frankliniella occidentalis) resistance in Senecio hybrids.

    Science.gov (United States)

    Leiss, Kirsten A; Choi, Young H; Abdel-Farid, Ibrahim B; Verpoorte, Robert; Klinkhamer, Peter G L

    2009-02-01

    Western flower thrips (Frankliniella occidentalis) has become a key insect pest of agricultural and horticultural crops worldwide. Little is known about host plant resistance to thrips. In this study, we investigated thrips resistance in F (2) hybrids of Senecio jacobaea and Senecio aquaticus. We identified thrips-resistant hybrids applying three different bioassays. Subsequently, we compared the metabolomic profiles of these hybrids applying nuclear magnetic resonance spectroscopy (NMR). The new developments of NMR facilitate a wide range coverage of the metabolome. This makes NMR especially suitable if there is no a priori knowledge of the compounds related to herbivore resistance and allows a holistic approach analyzing different chemical compounds simultaneously. We show that the metabolomes of thrips-resistant and -susceptible hybrids differed considerably. Thrips-resistant hybrids contained higher amounts of the pyrrolizidine alkaloids (PA), jacobine, and jaconine, especially in younger leaves. Also, a flavanoid, kaempferol glucoside, accumulated in the resistant plants. Both PAs and kaempferol are known for their inhibitory effect on herbivores. In resistant and susceptible F (2) hybrids, young leaves showed less thrips damage than old leaves. Consistent with the optimal plant defense theory, young leaves contained increased levels of primary metabolites such as sucrose, raffinose, and stachyose, but also accumulated jacaranone as a secondary plant defense compound. Our results prove NMR as a promising tool to identify different metabolites involved in herbivore resistance. It constitutes a significant advance in the study of plant-insect relationships, providing key information on the implementation of herbivore resistance breeding strategies in plants.

  10. Growth, morphology, and developmental instability of rainbow trout, Yellowstone cutthroat trout, and four hybrid generations

    Science.gov (United States)

    Ostberg, C.O.; Duda, J.J.; Graham, J.H.; Zhang, S.; Haywood, K. P.; Miller, B.; Lerud, T.L.

    2011-01-01

    Hybridization of cutthroat trout Oncorhynchus clarkii with nonindigenous rainbow trout O. mykiss contributes to the decline of cutthroat trout subspecies throughout their native range. Introgression by rainbow trout can swamp the gene pools of cutthroat trout populations, especially if there is little selection against hybrids. We used rainbow trout, Yellowstone cutthroat trout O. clarkii bouvieri, and rainbow trout × Yellowstone cutthroat trout F1 hybrids as parents to construct seven different line crosses: F1 hybrids (both reciprocal crosses), F2 hybrids, first-generation backcrosses (both rainbow trout and Yellowstone cutthroat trout), and both parental taxa. We compared growth, morphology, and developmental instability among these seven crosses reared at two different temperatures. Growth was related to the proportion of rainbow trout genome present within the crosses. Meristic traits were influenced by maternal, additive, dominant, overdominant, and (probably) epistatic genetic effects. Developmental stability, however, was not disturbed in F1 hybrids, F2 hybrids, or backcrosses. Backcrosses were morphologically similar to their recurrent parent. The lack of developmental instability in hybrids suggests that there are few genetic incompatibilities preventing introgression. Our findings suggest that hybrids are not equal: that is, growth, development, character traits, and morphology differ depending on the genomic contribution from each parental species as well as the hybrid generation.

  11. Superionic conductors with the fluorite structure: a) Measurement of the ionic conductivity of SrF2 at high temperatures, b) Study of the thermodynamic properties at CaF2 by numerical simulation

    International Nuclear Information System (INIS)

    Evangelakis, Georges

    1989-01-01

    In this work we present the results of an experimental study concerning the superionic conductivity of SrF 2 and those obtained by an investigation of the thermodynamical properties of CaF 2 using molecular dynamics simulation in the superionic region. The conductivity measurements in SrF 2 have been performed at high temperatures (700-1350 K) and various frequencies (10 Hz-10 MHz). At each temperature a frequency dependence of the conductivity has been detected. The analysis of the results using complex impedance diagrams revealed that this dependence is not an intrinsic property of the material but is related to electrodes effects. The apparent activation energies associated to the different parts of the intrinsic and extrinsic conductivity regions have been determined. Unfortunately no clear conclusion relative to the conduction mechanism can be made there from. Computer simulations by molecular dynamics have been performed in CaF 2 modeled using a rigid ion potential. The diffusion coefficient, the specific heat, structure factors, mean square displacements of both anions and cations, as well as the temperature dependence of these quantities have been calculated. The good agreement found between calculated quantities and experimental results justified us in using the crude approximation of a rigid on potential. A direct computation of the superionic conductivity has been obtained for the first time using non-equilibrium molecular dynamics in the linear response regime. From the independent calculation of the diffusion coefficient and the conductivity, the Havens ratio has been deduced, Hr 0.34, in the superionic region. Its value suggests that the superionic conductivity of CaF 2 is due to a collective and correlated mechanism, a fact which has been confirmed by the MD trajectory analysis. (author) [fr

  12. Prostaglandin F2α–F-Prostanoid Receptor Signalling Promotes Neutrophil Chemotaxis via Chemokine (CXC motif) Ligand-1 in Endometrial Adenocarcinoma

    Science.gov (United States)

    Wallace, Alison E; Sales, Kurt J; Catalano, Roberto D; Anderson, Richard A; Williams, Alistair RW; Wilson, Martin R; Schwarze, Jurgen; Wang, Hongwei; Rossi, Adriano G; Jabbour, Henry N

    2009-01-01

    The prostaglandin F2α (PGF2α) receptor (FP) is elevated in endometrial adenocarcinoma. This study found that PGF2α signalling via FP regulates expression of chemokine (C-X-C motif) ligand 1 (CXCL1) in endometrial adenocarcinoma cells. Expression of CXCL1 and its receptor, CXCR2, are elevated in cancer tissue as compared to normal endometrium and localised to glandular epithelium, endothelium and stroma. Treatment of Ishikawa cells stably transfected with the FP receptor (FPS cells) with 100nM PGF2α increased CXCL1 promoter activity, mRNA and protein expression, and these effects were abolished by co-treatment of cells with FP antagonist or chemical inhibitors of Gq, EGFR and ERK. Similarly, CXCL1 was elevated in response to 100 nM PGF2α in endometrial adenocarcinoma explant tissue. CXCL1 is a potent neutrophil chemoattractant. The expression of CXCR2 colocalised to neutrophils in endometrial adenocarcinoma and increased neutrophils were present in endometrial adenocarcinoma compared with normal endometrium. Conditioned media from PGF2α-treated FPS cells stimulated neutrophil chemotaxis which could be abolished by CXCL1 protein immunoneutralisation of the conditioned media or antagonism of CXCR2. Finally, xenograft tumours in nude mice arising from inoculation with FPS cells showed increased neutrophil infiltration compared to tumours arising from wild-type cells or following treatment of mice bearing FPS tumours with CXCL1-neutralising antibody. In conclusion, our results demonstrate a novel PGF2α-FP pathway that may regulate the inflammatory microenvironment in endometrial adenocarcinoma via neutrophil chemotaxis. PMID:19549892

  13. Production, crystallization and preliminary X-ray diffraction analysis of the allergen Can f 2 from Canis familiaris

    International Nuclear Information System (INIS)

    Madhurantakam, Chaithanya; Nilsson, Ola B.; Jönsson, Klas; Grönlund, Hans; Achour, Adnane

    2009-01-01

    The recombinant form of the allergen Can f 2 from C. familiaris was produced, isolated and crystallized in two different forms. Preliminary X-ray diffraction analyses are reported for the two crystal forms of Can f 2. The allergen Can f 2 from dog (Canis familiaris) present in saliva, dander and fur is an important cause of allergic sensitization worldwide. Here, the production, isolation, crystallization and preliminary X-ray diffraction analysis of two crystal forms of recombinant Can f 2 are reported. The first crystal form belonged to space group C222, with unit-cell parameters a = 68.7, b = 77.3, c = 65.1 Å, and diffracted to 1.55 Å resolution, while the second crystal form belonged to space group C2, with unit-cell parameters a = 75.7, b = 48.3, c = 68.7 Å, β = 126.5°, and diffracted to 2.1 Å resolution. Preliminary data analysis indicated the presence of a single molecule in the asymmetric unit for both crystal forms

  14. Influences of Er3+ content on structure and upconversion emission of oxyfluoride glass ceramics containing CaF2 nanocrystals

    International Nuclear Information System (INIS)

    Chen Daqin; Wang Yuansheng; Yu Yunlong; Ma En; Bao Feng; Hu Zhongjian; Cheng Yao

    2006-01-01

    Transparent 45SiO 2 -25Al 2 O 3 -5CaO-10NaF-15CaF 2 glass ceramics doped with different content of erbium ion (Er 3+ ) were prepared. X-ray diffraction (XRD) and transmission electron microscope (TEM) analyses evidenced the spherical CaF 2 nanocrystals homogeneously embedded among the glassy matrix. With increasing of Er 3+ content, the size of CaF 2 nanocrystals decreased while the number density increased. The crystallization kinetics studies revealed that CaF 2 crystallization was a diffusion-controlled growth process from small dimensions with decreasing nucleation rate. Er 3+ could act as nucleating agent to lower down crystallization temperature, while some of them may stay at the crystal surfaces to retard the growth of crystal. Intense red and weak green upconversion emissions were recorded for glass ceramics and their intensities increased with the increasing of Er 3+ content under 980 nm excitation. However, the concentration quenching effect appeared when Er 3+ doping reached 2 mol%. These results could be attributed to the change of ligand field of Er 3+ ions due to the incorporation of Er 3+ ions into precipitated fluoride nanocrystals

  15. Learners' Perceptions of Blended Learning and the Roles and Interaction of f2f and Online Learning

    Science.gov (United States)

    Huang, Qiang

    2016-01-01

    The present study aims to probe into learners' perceptions of blended learning in relation to the respective roles of face-to-face learning (f2f learning) and online learning as well as their interaction in the blended EFL contexts. Questionnaires were used in the study to examine the attitudes of 296 university students towards a blended English…

  16. Computing K and D meson masses with N-f=2+1+1 twisted mass lattice QCD

    NARCIS (Netherlands)

    Baron, Remi; Boucaud, Philippe; Carbonell, Jaume; Drach, Vincent; Farchioni, Federico; Herdoiza, Gregorio; Jansen, Karl; Michael, Chris; Montvay, Istvan; Pallante, Elisabetta; Pene, Olivier; Reker, Siebren; Urbach, Carsten; Wagner, Marc; Wenger, Urs

    We discuss the computation of the mass of the K and D mesons within the framework of N-f = 2 + 1 + 1 twisted mass lattice QCD from a technical point of view. These quantities are essential, already at the level of generating gauge configurations, being obvious candidates to tune the strange and

  17. Assessment of apically extruded debris produced by the single-file ProTaper F2 technique under reciprocating movement.

    Science.gov (United States)

    De-Deus, Gustavo; Brandão, Maria Claudia; Barino, Bianca; Di Giorgi, Karina; Fidel, Rivail Antonio Sergio; Luna, Aderval Severino

    2010-09-01

    This study was designed to quantitatively evaluate the amount of dentin debris extruded from the apical foramen by comparing the conventional sequence of the ProTaper Universal nickel-titanium (NiTi) files with the single-file ProTaper F2 technique. Thirty mesial roots of lower molars were selected, and the use of different instrumentation techniques resulted in 3 groups (n=10 each). In G1, a crown-down hand-file technique was used, and in G2 conventional ProTaper Universal technique was used. In G3, ProTaper F2 file was used in a reciprocating motion. The apical finish preparation was equivalent to ISO size 25. An apparatus was used to evaluate the apically extruded debris. Statistical analysis was performed using 1-way analysis of variance and Tukey multiple comparisons. No significant difference was found in the amount of the debris extruded between the conventional sequence of the ProTaper Universal NiTi files and the single-file ProTaper F2 technique (P>.05). In contrast, the hand instrumentation group extruded significantly more debris than both NiTi groups (P<.05). The present results yielded favorable input for the F2 single-file technique in terms of apically extruded debris, inasmuch as it is the most simple and cost-effective instrumentation approach. Copyright (c) 2010 Mosby, Inc. All rights reserved.

  18. Increased levels of the oxidative stress biomarker 8-iso-prostaglandin F2α in wastewater associated with tobacco use

    DEFF Research Database (Denmark)

    Ryu, Yeonsuk; Gracia-Lor, Emma; Bade, Richard

    2016-01-01

    oxidative stress at a community level. In this work, 8-iso-prostaglandin F2α (8-iso-PGF2α) was analysed in raw 24 h-composite wastewater samples collected from 4 Norwegian and 7 other European cities in 2014 and 2015. Using the same samples, biomarkers of alcohol (ethyl sulfate) and tobacco (trans-3...

  19. Critical frequency and maximum electron density of F2 region over four stations in the North American sector

    Czech Academy of Sciences Publication Activity Database

    Ezquer, R. G.; Cabrera, M. A.; López, J. L.; Albornoz, M. R.; Mosert, M.; Marcó, P.; Burešová, Dalia

    2011-01-01

    Roč. 73, č. 4 (2011), s. 420-429 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : Ionosphere * F2 region * Critical frequency * Electron density * Model Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.596, year: 2011 http://www.sciencedirect.com/science/article/pii/S1364682610002786

  20. Determination of etching parameters for pulsed XeF2 etching of silicon using chamber pressure data

    Science.gov (United States)

    Sarkar, Dipta; Baboly, M. G.; Elahi, M. M.; Abbas, K.; Butner, J.; Piñon, D.; Ward, T. L.; Hieber, Tyler; Schuberth, Austin; Leseman, Z. C.

    2018-04-01

    A technique is presented for determination of the depletion of the etchant, etched depth, and instantaneous etch rate for Si etching with XeF2 in a pulsed etching system in real time. The only experimental data required is the pressure data collected temporally. Coupling the pressure data with the knowledge of the chemical reactions allows for the determination of the etching parameters of interest. Using this technique, it is revealed that pulsed etching processes are nonlinear, with the initial etch rate being the highest and monotonically decreasing as the etchant is depleted. With the pulsed etching system introduced in this paper, the highest instantaneous etch rate of silicon was recorded to be 19.5 µm min-1 for an initial pressure of 1.2 Torr for XeF2. Additionally, the same data is used to determine the rate constant for the reaction of XeF2 with Si; the reaction is determined to be second order in nature. The effect of varying the exposed surface area of Si as well as the effect that pressure has on the instantaneous etch rate as a function of time is shown applying the same technique. As a proof of concept, an AlN resonator is released using XeF2 pulses to remove a sacrificial poly-Si layer.

  1. Suppression in the electrical hysteresis by using CaF2 dielectric layer for p-GaN MIS capacitors

    Science.gov (United States)

    Sang, Liwen; Ren, Bing; Liao, Meiyong; Koide, Yasuo; Sumiya, Masatomo

    2018-04-01

    The capacitance-voltage (C-V) hysteresis in the bidirectional measurements of the p-GaN metal-insulator-semiconductor (MIS) capacitor is suppressed by using a CaF2 dielectric layer and a post annealing treatment. The density of trapped charge states at the CaF2/p-GaN interface is dramatically reduced from 1.3 × 1013 cm2 to 1.1 × 1011/cm2 compared to that of the Al2O3/p-GaN interface with a large C-V hysteresis. It is observed that the disordered oxidized interfacial layer can be avoided by using the CaF2 dielectric. The downward band bending of p-GaN is decreased from 1.51 to 0.85 eV as a result of the low-density oxides-related trap states. Our work indicates that the CaF2 can be used as a promising dielectric layer for the p-GaN MIS structures.

  2. Dosimetry characterization of the commercial CaF2 for beta radiation of 90Sr + 90Y

    International Nuclear Information System (INIS)

    Oliveira, Mercia L.; Caldas, Linda V.E.

    2003-01-01

    This work studies the dosimetric characteristics of the CaF 2 commercial dosimetry for detection of 90 Sr + 90 Y beta radiation for using in the calibration of flat and concave appliers. Were determined the repetitiousness and linearity of answers of the samples, and their calibration curves

  3. Optical absorption of BaF2 crystals with different prehistory when irradiated by high-energy electrons

    International Nuclear Information System (INIS)

    Chinkov, E P; Stepanov, S A; Shtan'ko, V F; Ivanova, T S

    2016-01-01

    The spectra of stable optical absorption of BaF 2 crystals containing uncontrollable impurities after irradiation with 3 MeV electrons are studied at room temperature. The dependence of the efficiency of stable color accumulation in the region of emerging crossluminescence on the absorption coefficients measured near the fundamental absorption edge in unirradiated crystals of various prehistory is traced. (paper)

  4. An integrated interspecific AFLP map of lettuce (Lactuca) based on two L. Saligna x L. sativa F2-populations

    NARCIS (Netherlands)

    Jeuken, M.; Wijk, van R.; Peleman, J.; Lindhout, P.

    2001-01-01

    AFLP markers were obtained with 12 EcoRI/ MseI primer combinations on two independent F2 populations of Lactuca sativa 2 Lactuca saligna. The polymorphism rates of the AFLP products between the two different L. saligna lines was 39°between the two different L. sativa cultivars 13 nd between the L.

  5. A time-variant analysis of the 1/f^(2) phase noise in CMOS parallel LC-Tank quadrature oscillators

    DEFF Research Database (Denmark)

    Andreani, Pietro

    2006-01-01

    This paper presents a study of 1/f2 phase noise in quadrature oscillators built by connecting two differential LC-tank oscillators in a parallel fashion. The analysis clearly demonstrates the necessity of adopting a time-variant theory of phase noise, where a more simplistic, time...

  6. Bacterial effector HopF2 interacts with AvrPto and suppresses Arabidopsis innate immunity at the plasma membrane

    Science.gov (United States)

    Plant pathogenic bacteria inject a cocktail of effector proteins into host plant cells to modulate the host immune response, thereby promoting pathogenicity. How or whether these effectors work cooperatively is largely unknown. The Pseudomonas syringae DC3000 effector HopF2 suppresses the host plan...

  7. Production of Ginsenoside F2 by Using Lactococcus lactis with Enhanced Expression of β-Glucosidase Gene from Paenibacillus mucilaginosus.

    Science.gov (United States)

    Li, Ling; Shin, So-Yeon; Lee, Soo Jin; Moon, Jin Seok; Im, Wan Taek; Han, Nam Soo

    2016-03-30

    This study aimed to produce a pharmacologically active minor ginsenoside F2 from the major ginsenosides Rb1 and Rd by using a recombinant Lactococcus lactis strain expressing a heterologous β-glucosidase gene. The nucleotide sequence of the gene (BglPm) was derived from Paenibacillus mucilaginosus and synthesized after codon optimization, and the two genes (unoptimized and optimized) were expressed in L. lactis NZ9000. Codon optimization resulted in reduction of unfavorable codons by 50% and a considerable increase in the expression levels (total activities) of β-glucosidases (0.002 unit/mL, unoptimized; 0.022 unit/mL, optimized). The molecular weight of the enzyme was 52 kDa, and the purified forms of the enzymes could successfully convert Rb1 and Rd into F2. The permeabilized L. lactis expressing BglPm resulted in a high conversion yield (74%) of F2 from the ginseng extract. Utilization of this microbial cell to produce F2 may provide an alternative method to increase the health benefits of Panax ginseng.

  8. Heritability and genetic advance studies for biochemical traits in F2-3 introgressed families of Brassica

    International Nuclear Information System (INIS)

    Farhatullah, N.K.; Khalil, I.H.; Nahed, H.

    2015-01-01

    Higher heritability estimates along with high genetic advance values are effective in envisaging gain under selection in developing genotypes. The objective of the present study was to evaluate variability, heritability and genetic advance in 10 interspecific F2-3 families of Brassica species (B. napus * B. juncea, B. napus * B. rapa). These families were studied for heterospecific introgression of biochemical traits. Low to high heritability estimates were recorded for seed quality traits. Considerable variations within F2-3 families were observed for biochemical traits. Most of the F2-3 families for oil content and erucic showed moderate to high heritability indicating the slightest influence of environment thus modification of trait by selection would be more effective. Among F2-3 introgressed families Bn-510 x Bj-109 produced high oil i.e., 49.5% while Bn-532 x Br-118 (24.4%), Bn-533 x Bj-109 (24.1%) and high protein percentage in terms of mean performance. In the present research, individual segregating progenies of interspecific cross populations i.e., which possessed combination of desirable traits, were identified which could be incorporated in the future Breeding programs and it may facilitate varietal development. (author)

  9. Hybrid stars

    Indian Academy of Sciences (India)

    Hybrid stars. AsHOK GOYAL. Department of Physics and Astrophysics, University of Delhi, Delhi 110 007, India. Abstract. Recently there have been important developments in the determination of neutron ... number and the electric charge. ... available to the system to rearrange concentration of charges for a given fraction of.

  10. A prediction model of short-term ionospheric foF2 Based on AdaBoost

    Science.gov (United States)

    Zhao, Xiukuan; Liu, Libo; Ning, Baiqi

    Accurate specifications of spatial and temporal variations of the ionosphere during geomagnetic quiet and disturbed conditions are critical for applications, such as HF communications, satellite positioning and navigation, power grids, pipelines, etc. Therefore, developing empirical models to forecast the ionospheric perturbations is of high priority in real applications. The critical frequency of the F2 layer, foF2, is an important ionospheric parameter, especially for radio wave propagation applications. In this paper, the AdaBoost-BP algorithm is used to construct a new model to predict the critical frequency of the ionospheric F2-layer one hour ahead. Different indices were used to characterize ionospheric diurnal and seasonal variations and their dependence on solar and geomagnetic activity. These indices, together with the current observed foF2 value, were input into the prediction model and the foF2 value at one hour ahead was output. We analyzed twenty-two years’ foF2 data from nine ionosonde stations in the East-Asian sector in this work. The first eleven years’ data were used as a training dataset and the second eleven years’ data were used as a testing dataset. The results show that the performance of AdaBoost-BP is better than those of BP Neural Network (BPNN), Support Vector Regression (SVR) and the IRI model. For example, the AdaBoost-BP prediction absolute error of foF2 at Irkutsk station (a middle latitude station) is 0.32 MHz, which is better than 0.34 MHz from BPNN, 0.35 MHz from SVR and also significantly outperforms the IRI model whose absolute error is 0.64 MHz. Meanwhile, AdaBoost-BP prediction absolute error at Taipei station from the low latitude is 0.78 MHz, which is better than 0.81 MHz from BPNN, 0.81 MHz from SVR and 1.37 MHz from the IRI model. Finally, the variety characteristics of the AdaBoost-BP prediction error along with seasonal variation, solar activity and latitude variation were also discussed in the paper.

  11. Therapy of bovine endometritis with prostaglandin F2α: a meta-analysis.

    Science.gov (United States)

    Haimerl, P; Heuwieser, W; Arlt, S

    2013-05-01

    The objective of the conducted meta-analysis was to assess the efficacy of the treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum uterine infections have a high prevalence and a very negative effect on reproductive performance in dairy cattle. Because of a wide discordance between research results, a meta-analysis of the efficacy of the treatment of bovine endometritis with PGF(2α) was conducted. A comprehensive literature search was performed using online databases to reveal a total of 2,307 references. In addition, 5 articles were retrieved by reviewing citations. After applying specific exclusion criteria and evaluating specific evidence parameters, 5 publications, comprising 6 trials, were eligible for being analyzed by means of meta-analysis. Data for each trial were extracted and analyzed using meta-analysis software Review Manager (version 5.1; The Nordic Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were calculated on calving to first service and calving to conception interval. Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative effect on both reproductive performance parameters. Heterogeneity was substantial for calving to first service and calving to conception interval [I(2) (measure of variation beyond chance)=100 and 87%, respectively]; therefore, random-effects models were used. Sensitivity analysis as well as subgroup analysis showed that the performance of randomization was influential in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a publication bias toward smaller studies that reported a prolonged calving to conception interval after a PGF(2α) treatment. We conclude that the investigation of this subject by means of meta-analysis did not reveal an improvement of reproductive performance of cows with endometritis after treatment with PGF(2α). Furthermore, there is a shortage of comparable high quality studies investigating

  12. BaF2 POST-DEPOSITION REACTION PROCESS FOR THICK YBCO FILMS

    International Nuclear Information System (INIS)

    SUENAGA, M.; SOLOVYOV, V.F.; WU, L.; WIESMANN, H.J.; ZHU, Y.

    2001-01-01

    The basic processes of the so-called BaF 2 process for the formation of YBa 2 Cu 3 O 7 , YBCO, films as well as its advantages over the in situ formation processes are discussed in the previous chapter. The process and the properties of YBCO films by this process were also nicely described in earlier articles by R. Feenstra, (et al.) Here, we will discuss two pertinent subjects related to fabrication of technologically viable YBCO conductors using this process. These are (1) the growth of thick (>> 1 microm) c-axis-oriented YBCO films and (2) their growth rates. Before the detail discussions of these subjects are given, we first briefly discuss what geometrical structure a YBCO-coated conductor should be. Then, we will provide examples of simple arguments for how thick the YBCO films and how fast their growth rates need to be. Then, the discussions in the following two sections are devoted to: (1) the present understanding of the nucleation and the growth process for YBCO, and why it is so difficult to grow thick c-axis-oriented films (> 3 microm), and (2) our present understanding of the YBCO growth-limiting mechanism and methods to increase the growth rates. The values of critical-current densities J c in these films are of primary importance for the applications,. and the above two subjects are intimately related to the control of J c of the films. In general, the lower the temperatures of the YBCO formation are the higher the values of J c of the films. Thus, the present discussion is limited to those films which are reacted at ∼735 C. This is the lowest temperature at which c-axis-oriented YBCO films (1-3 microm thick) are comfortably grown. It is also well known that the non-c-axis oriented YBCO platelets are extremely detrimental to the values of J c such that their effects on J c dwarf essentially all of other microstructural effects which control J c . Hence, the discussion given below is mainly focused on how to avoid the growth of these crystallites

  13. QTL Analysis of Kernel-Related Traits in Maize Using an Immortalized F2 Population

    Science.gov (United States)

    Hu, Yanmin; Li, Weihua; Fu, Zhiyuan; Ding, Dong; Li, Haochuan; Qiao, Mengmeng; Tang, Jihua

    2014-01-01

    Kernel size and weight are important determinants of grain yield in maize. In this study, multivariate conditional and unconditional quantitative trait loci (QTL), and digenic epistatic analyses were utilized in order to elucidate the genetic basis for these kernel-related traits. Five kernel-related traits, including kernel weight (KW), volume (KV), length (KL), thickness (KT), and width (KWI), were collected from an immortalized F2 (IF2) maize population comprising of 243 crosses performed at two separate locations over a span of two years. A total of 54 unconditional main QTL for these five kernel-related traits were identified, many of which were clustered in chromosomal bins 6.04–6.06, 7.02–7.03, and 10.06–10.07. In addition, qKL3, qKWI6, qKV10a, qKV10b, qKW10a, and qKW7a were detected across multiple environments. Sixteen main QTL were identified for KW conditioned on the other four kernel traits (KL, KWI, KT, and KV). Thirteen main QTL were identified for KV conditioned on three kernel-shape traits. Conditional mapping analysis revealed that KWI and KV had the strongest influence on KW at the individual QTL level, followed by KT, and then KL; KV was mostly strongly influenced by KT, followed by KWI, and was least impacted by KL. Digenic epistatic analysis identified 18 digenic interactions involving 34 loci over the entire genome. However, only a small proportion of them were identical to the main QTL we detected. Additionally, conditional digenic epistatic analysis revealed that the digenic epistasis for KW and KV were entirely determined by their constituent traits. The main QTL identified in this study for determining kernel-related traits with high broad-sense heritability may play important roles during kernel development. Furthermore, digenic interactions were shown to exert relatively large effects on KL (the highest AA and DD effects were 4.6% and 6.7%, respectively) and KT (the highest AA effects were 4.3%). PMID:24586932

  14. Prostaglandin E and F2 alpha receptors in human myometrium during the menstrual cycle and in pregnancy and labor

    International Nuclear Information System (INIS)

    Giannopoulos, G.; Jackson, K.; Kredentser, J.; Tulchinsky, D.

    1985-01-01

    The binding of prostaglandins E1 and F2 alpha has been studied in the human myometrium and cervix during the menstrual cycle and in the myometrium of pregnant patients at term before and during labor. Tritium-labeled prostaglandin E1 and F2 alpha binding was saturable and reversible. Scatchard analysis of tritium-labeled prostaglandin E1 binding was linear, which suggests a single class of high-affinity binding sites with an estimated apparent equilibrium dissociation constant of 2.5 to 5.4 nmol/L and inhibitor affinities of 0.9, 273, 273, and 217 nmol/L for prostaglandins E2, A1, B1, and F2 alpha, respectively. Scatchard analysis of tritium-labeled prostaglandin F2 alpha, binding was also linear, but the affinity of these binding sites was much lower, with an average dissociation constant of 50 nmol/L and inhibitor affinities of 1.6, 2.2, and 11.2 nmol/L for prostaglandins E1, E2, and A1, respectively. In nonpregnant patients, the concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were similar in the myometrium during the proliferative and secretory phases of the menstrual cycle, but the concentration of these sites was much lower in the cervix. The concentration of the tritium-labeled prostaglandin E1 binding sites was significantly lower in the myometrium of pregnant patients at term than in the myometrium of nonpregnant patients. The concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were not significantly different in the upper and lower myometrium of pregnant patients at term or in the myometrium of such patients before and during labor. The concentrations of the tritium-labeled prostaglandin F2 alpha binding sites during the menstrual cycle and in pregnancy at term were similar to those of tritium-labeled prostaglandin E1 binding sites

  15. Prostaglandin E and F2 alpha receptors in human myometrium during the menstrual cycle and in pregnancy and labor

    Energy Technology Data Exchange (ETDEWEB)

    Giannopoulos, G.; Jackson, K.; Kredentser, J.; Tulchinsky, D.

    1985-12-15

    The binding of prostaglandins E1 and F2 alpha has been studied in the human myometrium and cervix during the menstrual cycle and in the myometrium of pregnant patients at term before and during labor. Tritium-labeled prostaglandin E1 and F2 alpha binding was saturable and reversible. Scatchard analysis of tritium-labeled prostaglandin E1 binding was linear, which suggests a single class of high-affinity binding sites with an estimated apparent equilibrium dissociation constant of 2.5 to 5.4 nmol/L and inhibitor affinities of 0.9, 273, 273, and 217 nmol/L for prostaglandins E2, A1, B1, and F2 alpha, respectively. Scatchard analysis of tritium-labeled prostaglandin F2 alpha, binding was also linear, but the affinity of these binding sites was much lower, with an average dissociation constant of 50 nmol/L and inhibitor affinities of 1.6, 2.2, and 11.2 nmol/L for prostaglandins E1, E2, and A1, respectively. In nonpregnant patients, the concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were similar in the myometrium during the proliferative and secretory phases of the menstrual cycle, but the concentration of these sites was much lower in the cervix. The concentration of the tritium-labeled prostaglandin E1 binding sites was significantly lower in the myometrium of pregnant patients at term than in the myometrium of nonpregnant patients. The concentrations and affinities of tritium-labeled prostaglandin E1 binding sites were not significantly different in the upper and lower myometrium of pregnant patients at term or in the myometrium of such patients before and during labor. The concentrations of the tritium-labeled prostaglandin F2 alpha binding sites during the menstrual cycle and in pregnancy at term were similar to those of tritium-labeled prostaglandin E1 binding sites.

  16. [Pb2F2](SeO4): a heavier analogue of grandreefite, the first layered fluoride selenate

    Science.gov (United States)

    Charkin, Dmitri O.; Plokhikh, Igor V.; Zadoya, Anastasiya I.; Kazakov, Sergey M.; Zaloga, Alexander N.; Kozin, Michael S.; Depmeier, Wulf; Siidra, Oleg I.

    2018-01-01

    Co-precipitation of PbF2 and PbSeO4 in weakly acidic media results in the formation of [Pb2F2](SeO4), the selenate analogue of the naturally occurring mineral grandreefite, [Pb2F2](SO4). The new compound is monoclinic, C2/ c, a = 14.0784(2) Å, b = 4.6267(1) Å, c = 8.8628(1) Å, β = 108.98(1)°, V = 545.93(1) Å3. Its structure has been refined from powder data to R B = 1.55%. From thermal studies, it is established that the compound is stable in air up to about 300 °C, after which it gradually converts into a single phase with composition [Pb2O](SeO4), space group C2/ m, and lattice parameters a = 14.0332(1) Å, b = 5.7532(1) Å, c = 7.2113(1) Å, β = 115.07(1)°, V = 527.37(1) Å3. It is the selenate analogue of lanarkite, [Pb2O](SO4), and phoenicochroite, [Pb2O](CrO4), and its crystal structure was refined to R B = 1.21%. The formation of a single decomposition product upon heating in air suggests that this happens by a thermal hydrolysis mechanism, i.e., Pb2F2SeO4 + H2O (vapor) → Pb2OSeO4 + 2HF↑. This relatively low-temperature process involves complete rearrangement of the crystal structure—from a 2D architecture featuring slabs [Pb2F2]2+ formed by fluorine-centered tetrahedra into a structure characterized by 1D motifs based on [OPb2]2+ chains of oxocentered tetrahedra. The comparative crystal chemistry of the obtained anion-centered structural architectures is discussed.

  17. Extensive hybridization and introgression between Melastoma candidum and M. sanguineum.

    Directory of Open Access Journals (Sweden)

    Ting Liu

    Full Text Available Natural hybridization can lead to various evolutionary outcomes in plants, including hybrid speciation and interspecific gene transfer. It can also cause taxonomic problems, especially in plant genera containing multiple species. In this study, the hybrid status of Melastoma affine, the most widespread taxon in this genus, and introgression between its putative parental species, M. candidum and M. sanguineum, were assessed on two sites, Hainan and Guangdong, using 13 SSR markers and sequences of a chloroplast intergenic spacer. Bayesian-based STRUCTURE analysis detected two most likely distinct clusters for the three taxa, and 76.0% and 73.9% of the morphologically identified individuals of M. candidum and M. sanguineum were correctly assigned, respectively. 74.5% of the M. affine individuals had a membership coefficient to either parental species between 0.1 and 0.9, suggesting admixture between M. candidum and M. sanguineum. Furthermore, NewHybrids analysis suggested that most individuals of M. affine were F2 hybrids or backcross hybrids to M. candidum, and that there was extensive introgression between M. candidum and M. sanguineum. These SSR data thus provides convincing evidence for hybrid origin of M. affine and extensive introgression between M. candidum and M. sanguineum. Chloroplast DNA results were consistent with this conclusion. Much higher hybrid frequency on the more disturbed Guangdong site suggests that human disturbance might offer suitable habitats for the survival of hybrids, a hypothesis that is in need of further testing.

  18. Systematic selection for increased fruit yield in populations derived from hybridization only, F1 irradiation, and hybridization following parental irradiation in peanuts (Arachis hypogaea L.)

    International Nuclear Information System (INIS)

    Emery, D.A.; Wynne, J.C.

    1976-01-01

    Three hybrid peanut populations involving a single pair of high yielding parents were developed to determine the effects of irradiation prior to and after hybridization on the response to selection for fruit yield. The control-hybrid population was produced by making reciprocal crosses between the two parents. The pre-hybrid-irradiated population was initiated by making reciprocal crosses between the M 1 plants of the two parents irradiated as seeds. The post-hybrid-irradiated population was developed by irradiating the mature F 1 embryos of crosses between the same parents. Each of the three original populations consisted of 55 F 1 plants. Ten F 2 plants were grown from each F 1 and one F 3 plant from each F 2 was used to initiate the yield tests. Selection for increased yield was practiced systematically and uniformly in each population over the F 3 to F 5 generations until the number of lines derived from single F 1 plants was reduced to five and the number of sublines descended from particular F 2 plants to three per line for yield trials in the F 6 generation. The mean yields of the F 1 derived lines of the irradiated populations were considerably below that of the control hybrid population when selection began but they reached 99% of the control mean in the F 6 generation. Selection gains in the irradiated populations appeared to result from the removal of inferior yielding sublines since greatest progress was made by raising the lower extremities of mean F 2 derived subline ranges rather than by extending the upper extremities of the ranges. The three highest yielding lines in the F6 generation occurred in the irradiated populations while the three highest yielding sublines were found in the hybrid-control population. No incidental association between size and yield of fruit was noted and a wide range of fruit sizes was found among the high yielding lines and sublines in all populations. (author)

  19. Ovulatory Follicular Dynamics After Estrus Synchronization using Prostaglandin F2a in Dairy Cows

    Directory of Open Access Journals (Sweden)

    Prabowo Purwono Putro

    2014-11-01

    Full Text Available The study aimed to follow development of ovulatory follicular dynamics as well as plasma progesterone profile after estrus synchronization using PGF2 and GnRH.   A total of 15 non-pregnant dairy cows, 4-5 years of age, healthy and reproductively sound were used in the present study.     Treatment 1, given intramuscular injection of PGF2 25 mg (PGF2, treatment 2 PGF2 25 mg and GnRH 250 g 2 days later (PGF2-GnRH, and treatment 3 with GnRH 250 g (7 days prior to injection of PGF2, PGF2 25 mg and GnRH 250 g (2 days after injection of PGF2  (GnRH-PGF2a-GnRH (the Ovsynch method.   Transrectal ultrasonographic examination using real time, B-mode, with 7.5 MHz tranducer was performed everyday for 12 days to follow ovulatory follicular and luteal dynamics.   Blood plasma was taken every day for progesterone determination using EIA technique.   Data of follicular, luteal development and progesterone levels were tested using analysis of variance and correlation analysis.   The animals showed estrus within 70.70 + 01.90 hours following PGF2 injection.   Prostaglandin F2 induced corpus luteum regression, decreased  in progesterone plasma levels, followed by ovulatory follicular development and eventually underwent ovulation.   Administration of first GnRH increased corpus luteum size, enhanced its regression and decreased plasma progesterone levels, while  the second administration induce  better ovulatory follicular development.   Rate of the corpus luteum regression, progesterone decrease and ovulatory follicular development following PGF2 injection for respective treatments 1, 2 and 3 were 2.53 + 0.24a, 2.73 + 0.36a and 3.53 + 0.28b mm/day; 1.39 + 0.14a,  1.35 + 0.18a dan 1.57 + 0.12b ng/ml/day; and 1.33 + 0.15a,  1.63 + 0.19b and 1.67 + 0.23b mm/day, respectively (P < 0.05.   It can be concluded that PGF2 induced corpus luteum regression, decreased in  progesterone plasma

  20. Solid solubility of MgO in the calcium silicates of portland clinker. The effect of CaF2

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    1992-03-01

    Full Text Available The solid solubility of MgO in the calcium silicates of portland clinker has been determined by XRD and XDS. The influence that the presence of CaF2 has on said solubility has also been verified. The solid solution limit of MgO in C3S at 1275 ºC lies at about 1.0% wt, where the triclinic form II stabilizes. The presence of CaF2 does not alter the maximum value of the MgO solubilized in that silicate, although there does take place the stabilization of the triclinic polymorph II at lower MgO contents (between 0.3 - 0.6% wt. The maximum amount of solubilized MgO in βC2 at 1.050 ºC lies around 0.5% wt. This value does not change by the presence of CaF2.Se ha determinado por DRX y EDX la solubilidad sólida del MgO en los silicatos cálcicos del clínker portland. Se ha comprobado, así mismo la influencia que sobre dicha solubilidad tiene la presencia de CaF2. El límite de disolución sólida del MgO en el C3S a 1.275º C se sitúa alrededor del 1,0% en peso, estabilizándose la forma triclínica II. La presencia de CaF2 no altera el valor máximo de MgO solubilizado en este silicato, aunque si se produce la estabilización del polimorfo triclínico II a contenidos menores de MgO (entre 0,3 – 0,6% en peso. La cantidad máxima de MgO solubilizado en e/ βC2S a 1.050 ºC se sitúa en torno al 0,5% en peso. Este valor no se ve modificado por la presencia de CaF2.

  1. Hybrid Monoterpenoid Indole Alkaloids Obtained as Artifacts from Rauvolfia tetraphylla.

    Science.gov (United States)

    Gao, Yuan; Zhou, Dong-Sheng; Hai, Ping; Li, Yan; Wang, Fei

    2015-10-01

    Five new hybrid monoterpenoid indole alkaloids bearing an unusual 2,2-dimethyl-4-oxopiperidin-6-yl moiety, namely rauvotetraphyllines F-H (1, 3, 4), 17-epi-rauvotetraphylline F (2) and 21-epi-rauvotetraphylline H (5), were isolated from the aerial parts of Rauvolfia tetraphylla. Their structures were established by extensive spectroscopic analysis. The new alkaloids were evaluated for their cytotoxicity in vitro against five human cancer cell lines.

  2. Hybrid Monoterpenoid Indole Alkaloids Obtained as Artifacts from Rauvolfia tetraphylla

    OpenAIRE

    Gao, Yuan; Zhou, Dong-Sheng; Hai, Ping; Li, Yan; Wang, Fei

    2015-01-01

    Abstract Five new hybrid monoterpenoid indole alkaloids bearing an unusual 2,2-dimethyl-4-oxopiperidin-6-yl moiety, namely rauvotetraphyllines F–H (1, 3, 4), 17-epi-rauvotetraphylline F (2) and 21-epi-rauvotetraphylline H (5), were isolated from the aerial parts of Rauvolfia tetraphylla. Their structures were established by extensive spectroscopic analysis. The new alkaloids were evaluated for their cytotoxicity in vitro against five human cancer cell lines. Graphical Abstract Electronic supp...

  3. EFICIÊNCIA AGRONÔMICA DOS RIZÓBIOS SEMIA 6156, F 3 (4, F 2 (1, F2 - 2B, CPAC-B10 EM FEIJÃO DE PORCO

    Directory of Open Access Journals (Sweden)

    Thiago Santos de Paula Silva

    2015-07-01

    Full Text Available O objetivo foi validar e recomendar bactérias fixadoras de nitrogênio usadas em inoculantes comerciais na leguminosa Canavalia ensiformis. O trabalho foi conduzido durante os meses de novembro de 2013 a fevereiro 2014. O delineamento experimental foi o de blocos ao acaso com quatro repetições e com unidade experimental de 24 m2, o plantio realizado no espaçamento de 0,5 m entre sulcos, densidade de 10 sementes por metro linear, As estirpes de rizóbio avaliadas foram: SEMIA 6156, F 3 (4, F 2 (1, F2 - 2B, CPAC-B10. A primeira avaliação foi realizada aos 30 dias após a semeadura (DAS, para número e massa de nódulos frescos e secos, massa seca da parte aérea e raízes. A segunda avaliação foi realizada quando 50% das plantas estavam em florescimento, quantificando-se a massa seca das folhas e caules, massa seca total da parte aérea e análise total de macronutrientes em folhas e caule. A estirpe F 2 (1 pode realizar efetiva simbiose com as plantas de feijão de porco, promovendo ganhos no acúmulo de massa seca de parte aérea das plantas, sendo assim considerada agronomicamente eficiente e recomendada para uso em inoculantes comerciais.

  4. PB1-F2 influenza A virus protein adopts a beta-sheet conformation and forms amyloid fibers in membrane environments.

    Science.gov (United States)

    Chevalier, Christophe; Al Bazzal, Ali; Vidic, Jasmina; Février, Vincent; Bourdieu, Christiane; Bouguyon, Edwige; Le Goffic, Ronan; Vautherot, Jean-François; Bernard, Julie; Moudjou, Mohammed; Noinville, Sylvie; Chich, Jean-François; Da Costa, Bruno; Rezaei, Human; Delmas, Bernard

    2010-04-23

    The influenza A virus PB1-F2 protein, encoded by an alternative reading frame in the PB1 polymerase gene, displays a high sequence polymorphism and is reported to contribute to viral pathogenesis in a sequence-specific manner. To gain insights into the functions of PB1-F2, the molecular structure of several PB1-F2 variants produced in Escherichia coli was investigated in different environments. Circular dichroism spectroscopy shows that all variants have a random coil secondary structure in aqueous solution. When incubated in trifluoroethanol polar solvent, all PB1-F2 variants adopt an alpha-helix-rich structure, whereas incubated in acetonitrile, a solvent of medium polarity mimicking the membrane environment, they display beta-sheet secondary structures. Incubated with asolectin liposomes and SDS micelles, PB1-F2 variants also acquire a beta-sheet structure. Dynamic light scattering revealed that the presence of beta-sheets is correlated with an oligomerization/aggregation of PB1-F2. Electron microscopy showed that PB1-F2 forms amorphous aggregates in acetonitrile. In contrast, at low concentrations of SDS, PB1-F2 variants exhibited various abilities to form fibers that were evidenced as amyloid fibers in a thioflavin T assay. Using a recombinant virus and its PB1-F2 knock-out mutant, we show that PB1-F2 also forms amyloid structures in infected cells. Functional membrane permeabilization assays revealed that the PB1-F2 variants can perforate membranes at nanomolar concentrations but with activities found to be sequence-dependent and not obviously correlated with their differential ability to form amyloid fibers. All of these observations suggest that PB1-F2 could be involved in physiological processes through different pathways, permeabilization of cellular membranes, and amyloid fiber formation.

  5. PB1-F2 Influenza A Virus Protein Adopts a β-Sheet Conformation and Forms Amyloid Fibers in Membrane Environments

    Science.gov (United States)

    Chevalier, Christophe; Al Bazzal, Ali; Vidic, Jasmina; Février, Vincent; Bourdieu, Christiane; Bouguyon, Edwige; Le Goffic, Ronan; Vautherot, Jean-François; Bernard, Julie; Moudjou, Mohammed; Noinville, Sylvie; Chich, Jean-François; Da Costa, Bruno; Rezaei, Human; Delmas, Bernard

    2010-01-01

    The influenza A virus PB1-F2 protein, encoded by an alternative reading frame in the PB1 polymerase gene, displays a high sequence polymorphism and is reported to contribute to viral pathogenesis in a sequence-specific manner. To gain insights into the functions of PB1-F2, the molecular structure of several PB1-F2 variants produced in Escherichia coli was investigated in different environments. Circular dichroism spectroscopy shows that all variants have a random coil secondary structure in aqueous solution. When incubated in trifluoroethanol polar solvent, all PB1-F2 variants adopt an α-helix-rich structure, whereas incubated in acetonitrile, a solvent of medium polarity mimicking the membrane environment, they display β-sheet secondary structures. Incubated with asolectin liposomes and SDS micelles, PB1-F2 variants also acquire a β-sheet structure. Dynamic light scattering revealed that the presence of β-sheets is correlated with an oligomerization/aggregation of PB1-F2. Electron microscopy showed that PB1-F2 forms amorphous aggregates in acetonitrile. In contrast, at low concentrations of SDS, PB1-F2 variants exhibited various abilities to form fibers that were evidenced as amyloid fibers in a thioflavin T assay. Using a recombinant virus and its PB1-F2 knock-out mutant, we show that PB1-F2 also forms amyloid structures in infected cells. Functional membrane permeabilization assays revealed that the PB1-F2 variants can perforate membranes at nanomolar concentrations but with activities found to be sequence-dependent and not obviously correlated with their differential ability to form amyloid fibers. All of these observations suggest that PB1-F2 could be involved in physiological processes through different pathways, permeabilization of cellular membranes, and amyloid fiber formation. PMID:20172856

  6. Difluoro-lambda(5)-phosphinonitrile F(2)P[triple bond]N: matrix isolation and photoisomerization into FP=NF.

    Science.gov (United States)

    Zeng, Xiaoqing; Beckers, Helmut; Willner, Helge

    2009-01-01

    Splendid isolation: Monomeric phosphazene F(2)PN ((1)A(1)) was prepared for the first time through irradiation of F(2)PN(3) in an argon matrix with an ArF excimer laser (lambda=193 nm). Upon subsequent irradiation with a high-pressure mercury arc lamp (lambda=255 nm), F(2)PN undergoes a 1,2-fluorine shift to give iminophosphane cis-FP=NF.

  7. A measurement of the photon structure function F$_{2}^{\\gamma}$ at an average Q$^{2}$ of 12 GeV$^{2}$/c$^{4}$ : results from DELPHI

    CERN Document Server

    Abreu, P; Adye, T; Agasi, E; Ajinenko, I; Aleksan, Roy; Alekseev, G D; Allport, P P; Almehed, S; Alvsvaag, S J; Amaldi, Ugo; Amato, S; Andreazza, A; Andrieux, M L; Antilogus, P; Apel, W D; Arnoud, Y; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barate, R; Bardin, Dimitri Yuri; Barker, G J; Baroncelli, A; Bärring, O; Barrio, J A; Bartl, Walter; Bates, M J; Battaglia, Marco; Batyunya, B; Baubillier, M; Baudot, J; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Belous, K S; Benvenuti, Alberto C; Berggren, M; Bertrand, D; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bloch, D; Blume, M; Blyth, S; Bocci, V; Bolognese, T; Bonesini, M; Bonivento, W; Booth, P S L; Borisov, G; Bosio, C; Bosworth, S; Botner, O; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Bricman, C; Brillault, L; Brown, R C A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Buys, A; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Cankocak, K; Cao, F; Carena, F; Carrilho, P; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Cerrito, L; Chabaud, V; Charpentier, P; Chaussard, L; Chauveau, J; Checchia, P; Chelkov, G A; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Cindro, V; Collins, P; Contreras, J L; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Dahl-Jensen, Erik; Dahm, J; D'Almagne, B; Dam, M; Damgaard, G; Daum, A; Dauncey, P D; Davenport, Martyn; Da Silva, W; Defoix, C; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; De Boeck, H; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; De Saint-Jean, C; Dijkstra, H; Di Ciaccio, Lucia; Djama, F; Dolbeau, J; Dönszelmann, M; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Dufour, Y; Dupont, F; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Elsing, M; Engel, J P; Ershaidat, N; Erzen, B; Espirito-Santo, M C; Falk, E; Fassouliotis, D; Feindt, Michael; Fenyuk, A; Ferrer, A; Filippas-Tassos, A; Firestone, A; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frenkiel, P; Fries, D E C; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fürstenau, H; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gibbs, M; Gillespie, D; Gokieli, R; Golob, B; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Graziani, E; Grosdidier, G; Gunnarsson, P; Günther, M; Guy, J; Haedinger, U; Hahn, F; Hahn, M; Hahn, S; Hajduk, Z; Hallgren, A; Hamacher, K; Hao, W; Harris, F J; Hedberg, V; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Higón, E; Hilke, Hans Jürgen; Hill, T S; Holmgren, S O; Holt, P J; Holthuizen, D J; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Ioannou, P; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, Christian; Juillot, P; Kaiser, M; Kalmus, George Ernest; Kapusta, F; Karlsson, M; Karvelas, E; Katsanevas, S; Katsoufis, E C; Keränen, R; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klein, H; Klovning, A; Kluit, P M; Köhne, J H; Köne, B; Kokkinias, P; Koratzinos, M; Korcyl, K; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Kramer, P H; Krammer, Manfred; Kreuter, C; Królikowski, J; Kronkvist, I J; Krumshtein, Z; Krupinski, W; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Laktineh, I; Lamblot, S; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Lapin, V; Last, I; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leitner, R; Lemoigne, Y; Lemonne, J; Lenzen, G; Lepeltier, V; Lesiak, T; Liko, D; Lindner, R; Lipniacka, A; Lippi, I; Lörstad, B; Lokajícek, M; Loken, J G; López, J M; López-Fernandez, A; López-Aguera, M A; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Maehlum, G; Maio, A; Malychev, V; Mandl, F; Marco, J; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Maron, T; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; Medbo, J; Meroni, C; Meyer, W T; Myagkov, A; Michelotto, M; Migliore, E; Mirabito, L; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Morettini, P; Müller, H; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Negri, P; Némécek, S; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Niss, P; Nomerotski, A; Normand, Ainsley; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Pagès, P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Piana, G; Pierre, F; Pimenta, M; Plaszczynski, S; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Prest, M; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Rames, J; Ratoff, P N; Read, A L; Reale, M; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Renton, P B; Resvanis, L K; Richard, F; Richardson, J; Rídky, J; Rinaudo, G; Ripp, I; Romero, A; Roncagliolo, I; Ronchese, P; Roos, L; Rosenberg, E I; Rosso, E; Roudeau, Patrick; Rovelli, T; Rückstuhl, W; Ruhlmann-Kleider, V; Ruiz, A; Rybicki, K; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sánchez, J; Sannino, M; Schneider, H; Schyns, M A E; Sciolla, G; Scuri, F; Sedykh, Yu; Segar, A M; Seitz, A; Sekulin, R L; Shellard, R C; Siccama, I; Siegrist, P; Simonetti, S; Simonetto, F; Sissakian, A N; Sitár, B; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stanescu, C; Stapnes, Steinar; Stavitski, I; Stepaniak, K; Stichelbaut, F; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tavernet, J P; Chikilev, O G; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Toet, D Z; Tomaradze, A G; Tomé, B; Tortora, L; Tranströmer, G; Treille, D; Trischuk, W; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; Van der Velde, C; van Apeldoorn, G W; van Dam, P; Van Doninck, W K; Van Eldik, J; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Waldner, F; Weierstall, M; Weilhammer, Peter; Wetherell, Alan M; Wicke, D; Wickens, J H; Wielers, M; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Woschnagg, K; Yip, K; Yushchenko, O P; Zach, F; Zacharatou-Jarlskog, C; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zito, M; Zontar, D; Zuberi, R; Zucchelli, G C; Zumerle, G

    1996-01-01

    The hadronic photon structure function F_{2}^{\\gamma} has been measured in the Q^{2} range from 4 to 30~GeV^2/c^{4} and down to x values of order 0.001, using data taken with the DELPHI detector at LEP between 1991 and 1993. A comparison is made with several F_{2}^{\\gamma} parameterizations with special emphasis on their low x behaviour. A result on the Q^{2} evolution of F_{2}^{\\gamma} is presented.

  8. Hybrid incompatibilities in the parasitic wasp genus Nasonia: negative effects of hemizygosity and the identification of transmission ratio distortion loci.

    Science.gov (United States)

    Koevoets, T; Niehuis, O; van de Zande, L; Beukeboom, L W

    2012-03-01

    The occurrence of hybrid incompatibilities forms an important stage during the evolution of reproductive isolation. In early stages of speciation, males and females often respond differently to hybridization. Haldane's rule states that the heterogametic sex suffers more from hybridization than the homogametic sex. Although haplodiploid reproduction (haploid males, diploid females) does not involve sex chromosomes, sex-specific incompatibilities are predicted to be prevalent in haplodiploid species. Here, we evaluate the effect of sex/ploidy level on hybrid incompatibilities and locate genomic regions that cause increased mortality rates in hybrid males of the haplodiploid wasps Nasonia vitripennis and Nasonia longicornis. Our data show that diploid F(1) hybrid females suffer less from hybridization than haploid F(2) hybrid males. The latter not only suffer from an increased mortality rate, but also from behavioural and spermatogenic sterility. Genetic mapping in recombinant F(2) male hybrids revealed that the observed hybrid mortality is most likely due to a disruption of cytonuclear interactions. As these sex-specific hybrid incompatibilities follow predictions based on Haldane's rule, our data accentuate the need to broaden the view of Haldane's rule to include species with haplodiploid sex determination, consistent with Haldane's original definition.

  9. Studies of wolf x coyote hybridization via artificial insemination

    Science.gov (United States)

    Mech, L. David; Asa, Cheryl S.; Callahan, Margaret; Christensen, Bruce W.; Smith, Fran; Young, Julie K.

    2017-01-01

    Following the production of western gray wolf (Canis lupus) x western coyote (Canis latrans) hybrids via artificial insemination (AI), the present article documents that the hybrids survived in captivity for at least 4 years and successfully bred with each other. It further reports that backcrossing one of the hybrids to a male gray wolf by AI also resulted in the birth of live pups that have survived for at least 10 months. All male hybrids (F1 and F2) produced sperm by about 10 months of age, and sperm quality of the F1 males fell within the fertile range for domestic dogs, but sperm motility and morphology, in particular, were low in F2 males at 10 months but improved in samples taken at 22 months of age. These studies are relevant to a long-standing controversy about the identity of the red wolf (Canis rufus), the existence of a proposed new species (Canis lycaon) of gray wolf, and to the role of hybridization in mammalian evolution.

  10. {lambda}{sub MS} from the static potential for QCD with n{sub f}=2 dynamical quark flavors

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Roma Univ. ' ' Tor Vergata' ' (Italy). Dipt. di Fisica; INFN, Roma (Italy); Karbstein, Felix [Helmholtz-Institut Jena (Germany); Jena Univ. (Germany). Theoretisch-Physikalisches Inst.; Nagy, Attila [Humboldt Univ. Berlin (Germany); Wagner, Marc [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik

    2011-12-15

    We determine {lambda}{sub MS} for QCD with n{sub f}=2 dynamical quark flavors by fitting the Q anti Q static potential known analytically in the perturbative regime up to terms of O({alpha}{sub s}{sup 4}) and {proportional_to}{alpha}{sub s}{sup 4} ln{alpha}{sub s} to corresponding results obtained from lattice simulations. This has become possible, due to recent advances in both perturbative calculations, namely the determination and publication of the last missing contribution to the Q anti Q static potential at O({alpha}{sub s}{sup 4}), and lattice simulations with n{sub f}=2 dynamical quark flavors performed at the rather fine lattice spacing of a{approx}0.042 fm. Imposing conservative error estimates we obtain {lambda}{sub MS}=315(30) MeV. (orig.)

  11. Parameters in the estimation of the most suitable F2 population size in conventional maize (Zea mays L. breeding programs

    Directory of Open Access Journals (Sweden)

    Delić Nenad

    2010-01-01

    Full Text Available The objective of the present study was to observe differences among four sizes of the F2 populations (100, 200, 300 and 500 plants on the basis of test-crosses for grain yield according to the average values of the populations, genetic and phenotypic variances, genotypic and phenotypic coefficients of variations and broad-sense heritability. The values of genetic variance did not significantly differ over population sizes according to all possible comparisons, including the comparison of values obtained for the phenotypic variance. Furthermore, the values of broadsense heritability (67.8%-69% did not significantly vary over different F2 population sizes. Genetic variability of the observed progenies, as a principal prerequisite of successful selection, was at the satisfactory level in all population sizes.

  12. The 4s- and 4p- XPS spectra of Xe, XeF2 and XeF4

    International Nuclear Information System (INIS)

    Ohno, Masahide

    2003-01-01

    The 4s- and 4p- XPS spectra of Xe gas, XeF 2 molecule and XeF 4 molecule are calculated by an ab-initio atomic many-body theory. The 4s-peak and the prominent '4p'-peak are predicted well by the present theory. In XeF 2 and XeF 4 the spectral lines observed below the 4d-double ionization threshold are the 4d -2 4f multiplet states strongly perturbed by the interaction with the initial 4p 1/2 -hole state. They are very similar to the spectral lines which emerge with an increase in atomic number (e.g. Ba)

  13. Influencia del CaF2 sobre la capacidad de reacción de crudos de cemento

    OpenAIRE

    Palomo, Ángel; Blanco, M. Teresa

    1982-01-01

    En este trabajo se estudia el efecto de una pequeña cantidad de CaF2 sobre la capacidad de reacción de crudos de cemento, para lo cual se comparan los comportamientos térmicos en función del tiempo de clinkerización de un crudo comercial con y sin adición de CaF2. Se da una estimación de los tiempos necesarios para completar las reacciones a diferentes temperaturas. El efecto mineralizador del espato-fluor pasa por un máximo a temperaturas de clinkerización del orden de 1.200ºC y tiempos d...

  14. Effect of Conway Medium and f/2 Medium on the growth of six genera of South China Sea marine microalgae.

    Science.gov (United States)

    Lananan, Fathurrahman; Jusoh, Ahmad; Ali, Nora'aini; Lam, Su Shiung; Endut, Azizah

    2013-08-01

    A study was performed to determine the effect of Conway and f/2 media on the growth of microalgae genera. Genera of Chlorella sp., Dunaliella sp., Isochrysis sp., Chaetoceros sp., Pavlova sp. and Tetraselmis sp. were isolated from the South China Sea. During the cultivation period, the density of cells were determined using Syringe Liquid Sampler Particle Measuring System (SLS-PMS) that also generated the population distribution curve based on the size of the cells. The population of the microalgae genera is thought to consist of mother and daughter generations since these microalgae genera reproduce by releasing small non-motile reproductive cells (autospores). It was found that the reproduction of Tetraselmis sp., Dunaliella sp. and Pavlova sp. could be sustained longer in f/2 Medium. Higher cell density was achieved by genus Dunaliella, Chlorella and Isochrysis in Conway Medium. Different genera of microalgae had a preference for different types of cultivation media. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. A modeling study of ionospheric F2-region storm effects at low geomagnetic latitudes during 17-22 March 1990

    Directory of Open Access Journals (Sweden)

    A. V. Pavlov

    2006-05-01

    Full Text Available We have presented a comparison between the modeled NmF2 and hmF2, and NmF2 and hmF2, which were observed in the low-latitude ionosphere simultaneously by the Kokubunji, Yamagawa, Okinawa, Manila, Vanimo, and Darwin ionospheric sounders, by the middle and upper atmosphere (MU radar during 17-22 March 1990, and by the Arecibo radar for the time period of 20-22 March 1990. A comparison between the electron and ion temperatures measured by the MU and Arecibo radars and those produced by the model of the ionosphere and plasmasphere is presented. The empirical zonal electric field, the meridional neutral wind taken from the HWM90 wind model, and the NRLMSISE-00 neutral temperature and densities are corrected so that the model results agree reasonably with the ionospheric sounder observations, and the MU and Arecibo radar data. It is proved that the nighttime weakening of the equatorial zonal electric field (in comparison with that produced by the empirical model of Fejer and Scherliess (1997 or Scherliess and Fejer (1999, in combination with the corrected wind-induced plasma drift along magnetic field lines, provides the development of the nighttime enhancements in NmF2 observed over Manila during 17-22 March 1990. As a result, the new physical mechanism of the nighttime NmF2 enhancement formation close to the geomagnetic equator includes the nighttime weakening of the equatorial zonal electric field and equatorward nighttime plasma drift along magnetic field lines caused by neutral wind in the both geomagnetic hemispheres. It is found that the latitudinal positions of the crests depend on the E×B drift velocity and on the neutral wind velocity. The relative role of the main mechanisms of the equatorial anomaly suppression observed during geomagnetic storms is studied for the first time in terms of storm-time variations of the model crest-to-trough ratios of the equatorial anomaly. During most of the studied time period, a total contribution from

  16. Effect of γ-irradiation on F-2 and T-2 toxin production in corn a rice

    International Nuclear Information System (INIS)

    Halasz, A.; Badaway, A.; Sawinsky, J.; Kozma-Kovacs, E.; Beczner, J.

    1989-01-01

    Fusarium graminearum and F. tricinctum were grown on moistened corn and rice. After inoculation the substrates were exposed to γ radiation and the growth rate and mycotoxin production were measured. A delay in mycelium growth and an increase in F-2 and T-2 toxin production occurred after irradiation with 1 and 3 kGy. The maximum F-2 production was 10.7 mg/kg for rice at 3 kGy whereas for T-2 it was 735 μg/kg for rice at 3 kGy. At 9 kGy neither growth nor toxin production could be detected in any inoculated corn and rice substrate. (author). 3 tabs., 12 refs

  17. Inclusive production of $\\rho^{0}(770), f_0(980)$ and $f_2(1270)$ mesons in $\

    CERN Document Server

    Astier, P.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, Barry J.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P.W.; Cavasinni, V.; Cervera-Villanueva, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; Del Prete, T.; De Santo, Antonella; Dignan, T.; Di Lella, L.; do Couto e Silva, E.; Dumarchez, J.; Ellis, Malcolm; Fazio, T.; Feldman, G.J.; Ferrari, R.; Ferrere, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.M.; Gangler, E.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.J.; Gosset, J.; Gossling, C.; Gouanere, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kuznetsov, V.; Lacaprara, S.; Lachaud, C.; Lakic, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.M.; Linssen, L.; Ljubicic, A.; Long, J.; Lupi, A.; Marchionni, A.; Martelli, F.; Mechain, X.; Mendiburu, J.P.; Meyer, J.P.; Mezzetto, M.; Mishra, S.R.; Moorhead, G.F.; Naumov, D.; Nedelec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L.S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Popov, B.; Poulsen, C.; Rathouit, P.; Rico, J.; Roda, C.; Rubbia, A.; Salvatore, F.; Schahmaneche, K.; Schmidt, B.; Sevior, M.; Sillou, D.; Soler, F.J.P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipcevic, M.; Stolarczyk, T.; Tareb-Reyes, M.; Taylor, G.N.; Tereshchenko, V.; Toropin, A.; Touchard, A.M.; Tovey, S.N.; Tran, M.T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K.E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.M.; Vinogradova, T.; Weber, F.V.; Weisse, T.; Wilson, F.F.; Winton, L.J.; Yabsley, Bruce D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2001-01-01

    The inclusive production of the meson resonances $\\rho^{0}(770)$, $f_0(980)$ and $f_2(1270)$ in neutrino-nucleus charged current interactions has been studied with the NOMAD detector exposed to the wide band neutrino beam generated by 450 GeV protons at the CERN SPS. For the first time the $f_{0}(980)$ meson is observed in neutrino interactions. The statistical significance of its observation is 6 standard deviations. The presence of $f_{2}(1270)$ in neutrino interactions is reliably established. The average multiplicity of these three resonances is measured as a function of several kinematic variables. The experimental results are compared to the multiplicities obtained from a simulation based on the Lund model. In addition, the average multiplicity of $\\rho^{0}(770)$ in antineutrino - nucleus interactions is measured.

  18. Thermal evolution of low-temperature manganese centers in X-irradiated CaF2:Mn

    International Nuclear Information System (INIS)

    Jahan, M.S.; Cooke, D.W.

    1984-01-01

    Thermal evolution of the radiation-induced defects in CaF 2 :Mn (0.1% by weight) are investigated by ESR techniques. The Mn + resonance is found to decay at 200 K with an activation energy of 0.44 eV and frequency factor 2.8 x 10 8 s -1 which agree with previous luminescence and optical absorption measurements. This activation energy and decay temperature also agree with that of the previously described H center. It is concluded that the luminescence in CaF 2 :Mn results from thermal release of holes at H centers with ultimate recombination at Mn + ions producing excited state Mn 2+ (*). Relaxation yields the observed 500 nm emission characteristic of Mn 2+ . A second defect which decays at 150 K is observed but not identified. (author)

  19. Development of a BaF2 scintillation spectrometer for evaluation of photon energy spectra in workplaces around nuclear facilities

    International Nuclear Information System (INIS)

    Urabe, Itsumasa; Yoshimoto, Taka-aki; Kobayashi, Katsuhei; Akiyoshi, Tsunekazu; Tsujimoto, Tadashi; Nakashima, Yoshiyuki; Oda, Keiji.

    1997-01-01

    A BaF 2 scintillation spectrometer has been constructed for the determination of photon energy spectra in workplaces around nuclear facilities. Energy absorption spectra by the BaF 2 detector were calculated with the EGS4 Monte Carlo code in the energy region from 0.1 to 100 MeV and a response matrix of the spectrometer was obtained from the energy absorption spectra, of which the energy resolutions were modified to fit to the experimental results. With the irradiation experiments using neutron-capture gamma rays and those from radioactive sources, it became clear that photon energy spectra can be evaluated within an error of about 10% in the energy region 0.1 MeV to a few tens of megaelectronvolts. (author)

  20. Preliminary report on electron energy-loss measurements for CCl3, CCl2F2, CCl3F

    International Nuclear Information System (INIS)

    Bushnell, D.L. Jr.; Huebner, R.H.; Celotta, R.J.; Mielczarek, S.R.

    1975-01-01

    Currently, nation-wide research efforts are devoted to studying the possible ozone (O 3 ) depletion in the stratosphere by the chemical action of chlorine atoms released from CCl 2 F 2 or CCl 3 F upon absorption of ultraviolet radiation. Since electron-impact data taken in the forward scattering direction can be used to derive oscillator strengths and thus to yield apparent photoabsorption cross sections, such an analysis for CCl 2 F 2 , CCLl 3 F, and CClF 3 was carried out. Oscillator-strength distributions were obtained between 5 and 20 eV and are compared to available photoabsorption data. Certain photoabsorption values agree very well with these electron-impact data, but other optical studies deviate in some spectral regions by as much as a factor of 5. Also, the electron energy-loss spectrum reveals electronic transitions previously undetected by photoabsorption

  1. Two-gap superconductivity with line nodes in CsCa2Fe4As4F2

    Science.gov (United States)

    Kirschner, Franziska K. K.; Adroja, Devashibhai T.; Wang, Zhi-Cheng; Lang, Franz; Smidman, Michael; Baker, Peter J.; Cao, Guang-Han; Blundell, Stephen J.

    2018-02-01

    We report the results of a muon-spin rotation (μ SR ) experiment to determine the superconducting ground state of the iron-based superconductor CsCa2Fe4As4F2 with Tc≈28.3 K . This compound is related to the fully gapped superconductor CaCsFe4As4 , but here the Ca-containing spacer layer is replaced with one containing Ca2F2 . The temperature evolution of the penetration depth strongly suggests the presence of line nodes and is best modeled by a system consisting of both an s - and a d -wave gap. We also find a potentially magnetic phase which appears below ≈10 K but does not appear to compete with the superconductivity. This compound contains the largest alkali atom in this family of superconductors, and our results yield a value for the in-plane penetration depth of λa b(T =0 ) =244 (3 ) nm .

  2. Perbedaan Kadar Prostaglandin F2α Cairan Darah Haid (Menstrual Fluid) Pada Dismenore Primer, Sekunder Dan Non Dismenore

    OpenAIRE

    Prahatama, Apriza

    2016-01-01

    Introduction: Prevalence of dysmenorrhea, pain at lower abdomen during menstruation, is increasing in reproductive women. Prostaglandin plays an important role in pain stimuli, but no its level is unknown each classification dysmenorrhea. Objective: To determine differences of prostaglandin F2α levels between primary, secondary and non dysmenorrhea. Methods: This study is a comparative analytical study with cross sectional design conducted in H. Adam Malik Hospital from November 2015 to...

  3. The effects of Eu-concentrations on the luminescent properties of SrF2:Eu nanophosphor

    International Nuclear Information System (INIS)

    Yagoub, M.Y.A.; Swart, H.C.; Noto, L.L.; O’Connel, J.H.; Lee, M.E.; Coetsee, E.

    2014-01-01

    SrF 2 :Eu nanophosphors were successfully synthesized by the hydrothermal method. The structure of the nanophosphors was investigated with x-ray diffraction. The average crystallite size calculated using the Scherrer equation was in the range of 7.0 nm. The photoluminescence of Eu doped as-prepared SrF 2 nanophosphors were studied using different excitation sources. The samples showed emission from both the Eu oxidation states, Eu 2+ and Eu 3+ . At low Eu concentrations the emission from Eu 2+ centered at 416 nm was more dominant. While the narrow band of Eu 3+ emission intensity increased with an increase in the Eu concentration. High resolution x-ray photoelectron spectroscopy results indicated that the Eu was indeed in both Eu 2+ and Eu 3+ valance states. The presence of Eu 2+ and Eu 3+ in the system largely enhanced the response of the Eu 3+ under ultraviolet excitation. The time of flight-secondary ion mass spectrometry results suggested that the energy transfer between two ions was likely to occur. The relative photoluminescence intensity of the Eu 2+ rapidly decreased with an increasing laser beam irradiating time. This result would make the current Eu 2+ doped SrF 2 samples unsuitable candidates for several applications, such as white light-emitting diodes and wavelength conversion films for silicon photovoltaic cells. - Highlights: • SrF 2 : Eu nanophosphors were successfully synthesised (hydrothermal technique). • PL and XPS results showed enhanced absorption response of Eu 3+ UV excitation. • Eu concentrations more than 5 mol% improved fluorescence emission. • TOF-SIMS results suggested that the energy transfer from Eu 2+ to Eu 3+ is dominant

  4. f2f and cyberbullying among children in Northern Ireland: Data from the Kids Life and Times Surveys

    OpenAIRE

    MC GUCKIN, CONOR

    2010-01-01

    PUBLISHED Comparatively little is known about the nature, incidence and correlates of bully/victim problems in the Northern Ireland school system. The present study examined the prevalence of self-reported experiences of bully/ victim problems (f2f and cyber), and the relationship between such experiences and levels of psychological wellbeing among representative samples of primary school pupils who participated in the 2008 and 2009 `Kids Life and Times Survey? (ARK, 2...

  5. Application of alternative models to identify QTL for growth traits in an F2 Duroc x Pietrain pig resource population

    Directory of Open Access Journals (Sweden)

    Rumph Janice M

    2010-11-01

    Full Text Available Abstract Background A variety of analysis approaches have been applied to detect quantitative trait loci (QTL in experimental populations. The initial genome scan of our Duroc x Pietrain F2 resource population included 510 F2 animals genotyped with 124 microsatellite markers and analyzed using a line-cross model. For the second scan, 20 additional markers on 9 chromosomes were genotyped for 954 F2 animals and 20 markers used in the first scan were genotyped for 444 additional F2 animals. Three least-squares Mendelian models for QTL analysis were applied for the second scan: a line-cross model, a half-sib model, and a combined line-cross and half-sib model. Results In total, 26 QTL using the line-cross model, 12 QTL using the half-sib model and 3 additional QTL using the combined line-cross and half-sib model were detected for growth traits with a 5% false discovery rate (FDR significance level. In the line-cross analysis, highly significant QTL for fat deposition at 10-, 13-, 16-, 19-, and 22-wk of age were detected on SSC6. In the half-sib analysis, a QTL for loin muscle area at 19-wk of age was detected on SSC7 and QTL for 10th-rib backfat at 19- and 22-wk of age were detected on SSC15. Conclusions Additional markers and animals contributed to reduce the confidence intervals and increase the test statistics for QTL detection. Different models allowed detection of new QTL which indicated differing frequencies for alternative alleles in parental breeds.

  6. Dynamics of the diluted Ising antiferromagnet Fe0.42Zn0.58F2 at strong fields

    International Nuclear Information System (INIS)

    Rosales-Rivera, A.; Ferreira, J.M.; Montenegro, F.C.

    2001-01-01

    The random-field Ising model (RFIM) system Fe 0.42 Zn 0.58 F 2 is studied by magnetization and AC susceptibility measurements, under finite DC applied fields (H). For weak random fields (corresponding to H c (H) is accompanied by the critical slowing down inherent to the random field problem. For higher H, the PT is destroyed and a glassy dynamics dominates the magnetic behavior

  7. Microtomography-based comparison of reciprocating single-file F2 ProTaper technique versus rotary full sequence

    OpenAIRE

    Paqué, F; Zehnder, Matthias; De-Deus, G

    2011-01-01

    Introduction A preparation technique with only 1 single instrument was proposed on the basis of the reciprocating movement of the F2 ProTaper instrument. The present study was designed to quantitatively assess canal preparation outcomes achieved by this technique. Methods Twenty-five extracted human mandibular first molars with 2 separate mesial root canals were selected. Canals were randomly assigned to 1 of the 2 experimental groups: group 1, rotary conventional preparation by us...

  8. Microtomography-based comparison of reciprocating single-file F2 ProTaper technique versus rotary full sequence.

    Science.gov (United States)

    Paqué, Frank; Zehnder, Matthias; De-Deus, Gustavo

    2011-10-01

    A preparation technique with only 1 single instrument was proposed on the basis of the reciprocating movement of the F2 ProTaper instrument. The present study was designed to quantitatively assess canal preparation outcomes achieved by this technique. Twenty-five extracted human mandibular first molars with 2 separate mesial root canals were selected. Canals were randomly assigned to 1 of the 2 experimental groups: group 1, rotary conventional preparation by using ProTaper, and group 2, reciprocate instrumentation with 1 single ProTaper F2 instrument. Specimens were scanned initially and after root canal preparation with an isotropic resolution of 20 μm by using a micro-computed tomography system. The following parameters were assessed: changes in dentin volume, percent