61 research outputs found

    Functional Renormalization Group flows on Friedman-Lema\^{\i}tre-Robertson-Walker backgrounds

    Get PDF
    We reanalyze the construction of the gravitational functional renormalization group equation tailored to the Arnowitt-Deser-Misner formulation emphasizing its connection to the covariant formulation. The results obtained from projecting the renormalization group flow onto the Einstein-Hilbert action are reviewed in detail and we provide a novel example illustrating how the formalism may be connected to the Causal Dynamical Triangulations approach to quantum gravity.Comment: 14 pages, 2 figure

    INFluENCE OF VESSEl TypE, phySICal STaTE OF MEdIuM aNd TEMpOrary IMMErSION ON ThE MICrOprOpagaTION OF ThrEE Rhodophiala SpECIES

    Get PDF
    aBSTraCT Rhodophiala C. Presl (Amaryllidaceae) is a genus of attractive flowering geophytes native to South America. They have ornamental value, but most species are not well-known and have conservation problems. The objective of this study was to optimize a micropropagation process to support the use and preservation of three Chilean native species, R. montana (Phil.) Traub, R. splendens (Rengifo) Traub., and R. ananuca (Phil.) Traub. The research evaluated the feasibility of implementing liquid medium culture and assessed the influence of different tissue culture systems on the shoot production and biomass increment of small bulbs. Three experiments were carried out. The first one determined the influences of flask size and volume of media; the second compared liquid and solid media, and in the third experiment, a temporary immersion system (TIS), and conventional culture in static liquid, shaken liquid and gelled Murashige and Skoog (MS) media were compared. By using larger (350 mL) flasks with higher (50 mL) media volume, 100% more fresh weight of microbulb was obtained that treatment with smaller flasks (45 mL) and media volume (10 mL). In gelled medium, hyperhydricity affected only 5% of explants, while in liquid medium was 16-40%. Survival to acclimatization reached 87-94% for plants from gelled medium; from liquid medium only 38-69%. TIS yielded higher propagation rate (1.9 shoots in 30 d) compared with shaken liquid medium (1.0) (P < 0.05) in R. ananuca only. Current procedures are appropriate for the support of ex situ conservation and germplasm bank establishment

    Characterization of the acetohydroxyacid synthase multigene family in the tetraploide plant Chenopodium quinoa

    Get PDF
    Background: Currently, the technology called Clearfield\uae is used in the development of crops resistant to herbicides that inhibit the enzyme acetohydroxy acid synthase (AHAS, EC 2.2.1.6). AHAS is the first enzyme of the biosynthetic pathway that produces the branched-chain of the essential amino acids valine, leucine, and isoleucine. Therefore, multiple copies of the AHAS gene might be of interest for breeding programs targeting herbicide resistance. In this work, the characterization of the AHAS gene was accomplished for the Chenopodium quinoa Regalona-Baer cultivar. Cloning, sequencing, and Southern blotting were conducted to determine the number of gene copies. Results: The presence of multiple copies of the AHAS gene as has been shownpreviously in several other species is described. Six copies of the AHAS gene were confirmed with Southern blot analyses. CqHAS1 and CqAHAS2 variants showed the highest homology with AHAS mRNA sequences found in the NR Database. A third copy, CqAHAS3, shared similar fragments with both CqAHAS1 and CqAHAS2, suggesting duplication through homeologous chromosomes pairing. Conclusions: The presence of multiple copies of the gene AHAS shows that gene duplication is a common feature in polyploid species during evolution. In addition, to our knowledge, this is the first report of the interaction of sub-genomes in quinoa

    Relaciones filogenéticas de Rhodolirium montanum Phil. y especies afines, basadas en secuencias nucleotídicas de la región ITS y análisis cariotípico

    Get PDF
    The taxonomy of Chilean Amaryllidaceae is confusing. Taxonomic problems still persist at the level of genera and species. Currently there is controversy about the correct classification of species so far assigned to Rhodophiala C.Presl. Through the study of morphological characters, recently has been suggested the rehabilitation of the genus Rhodolirium Phil., where the species Rhodolirium montanum Phil. is considered as type species. This species was named Rhodophiala rhodolirion (Baker) Traub in traditional classifications. Since morphological data have provided limited and ambiguous information in the classification of Amaryllidaceae in Chile, this paper assesses the relevance of formalize the rehabilitation of genus Rhodolirium and particularly the resurrection of the species R. montanum, through an analysis of chromosomal morphology and nucleotide sequences of the ITS region of six native species of Amaryllidaceae. The molecular data indicate that the species Rhodophiala bagnoldii, R. montana, R. splendens, R. phycelloides and R. ananuca form a monophyletic group more closely related to Hippeastrum than Rhodolirium. This genus is presented as closely related to Phycella in the phylogenetic analysis using ITS sequences. This separation of Rhodolirium with respect Rhodophiala is supported by differences in chromosome number and morphology, presenting the fi rst, chromosome number of 2n = 16 and intrachromosomal asymmetry index (Isc) of 0.46, while the latter has 2n = 18 and Isc of 0.59 to 0.62. Thus, chromosomal and molecular results together differences in exomorphology already mentioned by other authors support the rehabilitation of the genus Rhodolirium Phil. and the resurrection of the species Rhodolirium montanum Phil.La taxonomía de los géneros chilenos de Amaryllidaceae es confusa, persistiendo problemas taxonómicos tanto a nivel de géneros como de especies. Actualmente existe controversia acerca de la correcta clasificación de especies hasta ahora asignadas a Rhodophiala C.Presl. A través del estudio de aspectos morfológicos, recientemente se ha sugerido la rehabilitación del género Rhodolirium Phil., donde Rhodolirium montanum Phil. es considerada como especie tipo. Esta especie ha sido denominada Rhodophiala rhodolirion (Baker) Traub en las clasifi caciones tradicionales. Dado que los datos morfológicos han provisto información limitada y ambigua en la clasificación de las Amarilidáceas chilenas, este trabajo evalúa la pertinencia de formalizar la rehabilitación del género Rhodolirium y en particular de la especie Rhodolirium montanum, a través de un análisis de morfología cromosómica y de secuencias nucleotídicas de la región ITS de seis especies nativas de Amaryllidaceae. Los datos moleculares indican que las especies Rhodophiala bagnoldii, R. montana, R. splendens, R. phycelloides y R. ananuca forman un grupo monofilético más emparentado con Hippeastrum Herb. que con Rhodolirium, género que se presenta como grupo hermano de Phycella en el análisis fi logenético. La separación de Rhodolirium con respecto de Rhodophiala está respaldada por diferencias en número y morfología cromosómica, presentando el primero un número cromosómico de 2n = 16 y un índice de asimetría intracromosómica (Isc) de 0,46; mientras que el segundo posee 2n = 18 e Isc de 0,59-0,62. De esta manera, los resultados de los estudios cromosómicos y moleculares, junto a diferencias en exomorfología, tales como forma del estigma, perigonio y paraperigonio, apoyan la validez del género Rhodolirium Phil. y por ende de la especie Rhodolirium montanum Phil

    TRISSOMIA DE PARTE DO BRAÇO LONGO DO CROMOSSOMO 6 COM INSERÇÃO EM 14Q EM PACIENTE COM RETARDO MENTAL LEVE E DISMORFIAS

    Get PDF
    This article presents the case of a male patient who presented mild mental retardation, clinodactyly, camptodactyly, abnormal pattern of the hand skinfolds and cleft palate. In addition to the clinical examination, conventional cytogenetic techniques with G-bands and fluorescence in situ hybridization (FISH) were used with probes WCP 14, WCP 6, and tel6p. Fif teen metaphases were analyzed through conventional cytogenetics. All cells presented additional material on chromosome 14 [46,XY,add(14)]. The patient’s mother presented karyotype 46,XX,t(6q;14q), and the patient’s father presented normal karyotype. The patient’s material was submitted to FISH technique with probe WCP 6. This procedure showed that the additional portion was originated in chromosome 6 inserted at 14q22. The subtelomeric probes 6p/q determined the four typical breakpoints. The patient’s clinical status is a consequence of a partial trisomy of chromosome 6. This additional material is inserted in chromosome 14 long arm. The chromosome originated from chromosome 14 has maternal origin.Descrevemos o paciente HP, do sexo masculino, o qual apresentava quadro clínico de retardo mental leve, clinodactilia, camptodactilia, padrão alterado das pregas nas mãos e fenda palatina incompleta. Além do exame clínico, foram utilizadas técnicas citogenéticas convencionais com bandas G e hibridização in situ por fluorescência (FISH) com as sondas WCP 14; WCP 6; tel6p; tel6q. Foram analisadas 15 metáfases por citogenética convencional (GTG), onde todas as células apresentaram material adicional no cromossomo 14 [46,XY,add(14)]. A mãe apresentou cariótipo 46,XX,t(6q;14q) e o pai, cariótipo normal. O material do paciente foi submetido à técnica de FISH com sonda WCP 6, evidenciando a porção adicional como sendo material do cromossomo 6 inserido em 14q22. As sondas subteloméricas 6p/q marcaram os quatro pontos normalmente esperados. O paciente apresenta quadro clínico que resultou de uma trissomia parcial do cromossomo 6. Este material adicional está inserido no braço longo do cromossomo 14. O cromossomo derivado de 14 tem origem materna

    Chromosome 6 partial trisomy with insertion in 14q in oatient with mental retardation and dysmorphic features

    Get PDF
    Descrevemos o paciente HP, do sexo masculino, o qual apresentava quadro clínico de retardo mental leve, clinodactilia, camptodactilia, padrão alterado das pregas nas mãos e fenda palatina incompleta. Além do exame clínico, foram utilizadas técnicas citogenéticas convencionais com bandas G e hibridização in situ por fluorescência (FISH) com as sondas WCP 14; WCP 6; tel6p; tel6q. Foram analisadas 15 metáfases por citogenética convencional (GTG), onde todas as células apresentaram material adicional no cromossomo 14 [46,XY,add(14)]. A mãe apresentou cariótipo 46,XX,t(6q;14q) e o pai, cariótipo normal. O material do paciente foi submetido à técnica de FISH com sonda WCP 6, evidenciando a porção adicional como sendo material do cromossomo 6 inserido em 14q22. As sondas subteloméricas 6p/q marcaram os quatro pontos normalmente esperados. O paciente apresenta quadro clínico que resultou de uma trissomia parcial do cromossomo 6. Este material adicional está inserido no braço longo do cromossomo 14. O cromossomo derivado de 14 tem origem materna.This article presents the case of a male patient who presented mild mental retardation, clinodactyly, camptodactyly, abnormal pattern of the hand skinfolds and clef t palate. In addition to the clinical examination, conventional cytogenetic techniques with G-bands and fluorescence in situ hybridization (FISH) were used with probes WCP 14, WCP 6, and tel6p. Fif teen metaphases were analyzed through conventional cytogenetics. All cells presented additional material on chromosome 14 [46,XY,add(14)]. The patient’s mother presented karyotype 46,XX,t(6q;14q), and the patient’s father presented normal karyotype. The patient’s material was submitted to FISH technique with probe WCP 6. This procedure showed that the additional portion was originated in chromosome 6 inserted at 14q22. The subtelomeric probes 6p/q determined the four typical breakpoints. The patient’s clinical status is a consequence of a partial trisomy of chromosome 6. This additional material is inserted in chromosome 14 long arm. The chromosome originated from chromosome 14 has maternal origin

    Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

    Get PDF
    The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

    Get PDF
    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Search for single production of vector-like quarks decaying into Wb in pp collisions at s=8\sqrt{s} = 8 TeV with the ATLAS detector

    Get PDF
    corecore