3,697,310 research outputs found
Running the running
We use the recent observations of Cosmic Microwave Background temperature and
polarization anisotropies provided by the Planck satellite experiment to place
constraints on the running and the running of the running of the spectral index
of primordial scalar fluctuations. We find
and at
, suggesting the presence of a running of the running at the
level of two standard deviations. We find no significant correlation between
and foregrounds parameters, with the exception of the
point sources amplitude at , , which shifts by
half sigma when the running of the running is considered. We further study the
cosmological implications of such preference for
by including in the analysis the
lensing amplitude , the curvature parameter , and the sum of
neutrino masses . We find that when the running of the running is
considered, Planck data are more compatible with the standard expectations of
and but still hint at possible deviations. The
indication for survives at two standard deviations when
external datasets such as BAO and CFHTLenS are included in the analysis, and
persists at standard deviations when CMB lensing is considered. We
discuss the possibility of constraining with current and
future measurements of CMB spectral distortions, showing that an experiment
like PIXIE could provide strong constraints on and
.Comment: 10+1 pages, 9 figures, 10 tables. Matches published versio
Mutations in the PERIANTHIA gene of Arabidopsis specifically alter floral organ number and initiation pattern
An open question in developmental biology is how groups of dividing cells can generate specific numbers of segments or organs. We describe the phenotypic effects of mutations in PERIANTHIA, a gene specifically required for floral organ patterning in Arabidopsis thaliana. Most wild-type Arabidopsis flowers have 4 sepals, 4 petals, 6 stamens, and 2 carpels. Flowers of perianthia mutant plants most commonly show a pentamerous pattern of 5 sepals, 5 petals 5 stamens, and 2 carpels. This pattern is characteristic of flowers in a number of plant families, but not in the family Brassicaceae, which includes Arabidopsis. Unlike previously described mutations affecting floral organ number, perianthia does not appear to affect apical or floral meristem sizes, nor is any other aspect of vegetative or floral development severely affected. Floral organs in perianthia arise in a regular, stereotypical pattern similar to that in distantly related species with pentamerous flowers. Genetic analysis shows that PERIANTHIA acts downstream of the floral meristem identity genes and independently of the floral meristem size and floral organ identity genes in establishing floral organ initiation patterns. Thus PERIANTHIA acts in a previously unidentified process required for organ patterning in Arabidopsis flowers
TSO1 functions in cell division during Arabidopsis flower development
We describe an Arabidopsis mutant, tso1, which develops callus-like tissues in place of floral organs. The tso1 floral meristem lacks properly organized three cell layers, and the nuclei of these cells are irregular in size and shape. Further analyses reveal partially formed cell walls and increased DNA ploidy in tso1 floral meristem cells, indicating defects in mitosis and cytokinesis. Our finding that TSO1 is required for organ formation in floral tissues but not in other tissues indicates that TSO1 may encode a floral-specific cell division component, or that TSO1 function is redundant in nonfloral tissues
CLAVATA3 is a specific regulator of shoot and floral meristem development affecting the same processes as CLAVATA1
We have previously described the phenotype of Arabidopsis thaliana plants with mutations at the CLAVATA1 (CLV1) locus (Clark, S. E., Running, M. P. and Meyerowitz, E. M. (1993) Development 119, 397-418). Our investigations demonstrated that clv1 plants develop enlarged vegetative and inflorescence apical meristems, and enlarged and indeterminate floral meristems. Here, we present an analysis of mutations at a separate locus, CLAVATA3(CLV3), that disrupt meristem development in a manner similar to clv1mutations. clv3 plants develop enlarged apical meristems as early as the mature embryo stage. clv3 floral meristems are also enlarged compared with wild type, and maintain a proliferating meristem throughout flower development. clv3 root meristems are unaffected, indicating that CLV3 is a specific regulator of shoot and floral meristem development. We demonstrate that the strong clv3-2 mutant is largely epistatic to clv1 mutants, and that the semi-dominance of clv1 alleles is enhanced by double heterozygosity with clv3 alleles, suggesting that these genes work in the same pathway to control meristem development. We propose that CLV1 and CLV3 are required to promote the differentiation of cells at the shoot and floral meristem
Interval Running Exercise Reduces Running TIME of 800 Meters Dash Without Causing Increased Level of Sgot – Sgpt in Male Students of the Faculty of Sports Sciences, Manado State University
The effort to gain best achievement in sports by means of exercise has twodilemmatic sides, both for the coaches and sport promoters. On one side, exercise shouldbe done intensely and maximally, but on the other side, it is a known fact that excessiveand maximal exercises can damage the body organs. The purposes of this study were toobserve the side effects of interval running exercise of 800 meters, to find out level offatigue by examining lactate acid produced by each model, and to assess the negativeeffects on organs as indicated by the level of SGOT-SGPT. The exercise model appliedin the study comprised interval running of 2 x 800 meters, 4 x 400 meters, 8 x 200meters, 16 x 100 meters and one standard of comparison exercise, which was runningexercise of 2 x 800 meters with passive rest. This study was true experimental usingrandomized pre-test-post-test control group design. Samples of this study were 27 malestudents of the Faculty of Sports Sciences, Manado State University, who were dividedinto five groups. Group 1 was with interval running exercise of 2 x 800 meters. Group 2was assigned to interval running exercise of 4 x 400 meters. Group 3 was with intervalrunning exercise of 8 x 200 meters. Group 4 was with interval running exercise of 16 x100 meters. Group 5 as comparison standard was with running exercise of 2 x 800 meterspassive rest. All the exercise models were carried out for six weeks, each with afrequency of three times a week. Results of the study showed that the five groupsdemonstrated reduction of running time of 800 meters dash (p<0.05), lactate acidproduction differed in some of the groups (p>0.05), levels of SGOT and SGPT of allgroups did not show significant increase (p>0.05). From the above findings, it can beconcluded that all exercise models of interval running 2 x 800 meters, 4 x 400 meters, 8 x200 meters, 16 x 100 meters and 2 x 800 meters with passive rest lowered the runningtime of 800 meters dash and did not increase level of SGOT-SGPT
Running Boundary Condition
In this paper we argue that boundary condition may run with energy scale. As
an illustrative example, we consider one-dimensional quantum mechanics for a
spinless particle that freely propagates in the bulk yet interacts only at the
origin. In this setting we find the renormalization group flow of U(2) family
of boundary conditions exactly. We show that the well-known scale-independent
subfamily of boundary conditions are realized as fixed points. We also discuss
the duality between two distinct boundary conditions from the renormalization
group point of view. Generalizations to conformal mechanics and quantum graph
are also discussed.Comment: PTPTeX, 21 pages, 8 eps figures; typos corrected, references and an
appendix adde
Running after Diphoton
A very plausible explanation for the recently observed diphoton excess at the
13 TeV LHC is a (pseudo)scalar with mass around 750 GeV, which couples to a
gluon pair and to a photon pair through loops involving vector-like quarks
(VLQs). To accommodate the observed rate, the required Yukawa couplings tend to
be large. A large Yukawa coupling would rapidly run up with the scale and
quickly reach the perturbativity bound, indicating that new physics, possibly
with a strong dynamics origin, is near by. The case becomes stronger especially
if the ATLAS observation of a large width persists. In this paper we study the
implication on the scale of new physics from the 750 GeV diphoton excess using
the method of renormalization group running with careful treatment of different
contributions and perturbativity criterion. Our results suggest that the scale
of new physics is generically not much larger than the TeV scale, in particular
if the width of the hinted (pseudo)scalar is large. Introducing multiple copies
of VLQs, lowing the VLQ masses and enlarging VLQ electric charges help reduce
the required Yukawa couplings and can push the cutoff scale to higher values.
Nevertheless, if the width of the 750 GeV resonance turns out to be larger than
about 1 GeV, it is very hard to increase the cutoff scale beyond a few TeVs.
This is a strong hint that new particles in addition to the 750 GeV resonance
and the vector-like quarks should be around the TeV scale.Comment: 19 pages, 6 figures; v3: corrected Eq.(2.6) and (3.1), updated
reference
Backward running or absence of running from Creutz ratios
We extract the running coupling based on Creutz ratios in SU(2) lattice gauge
theory with two Dirac fermions in the adjoint representation. Depending on how
the extrapolation to zero fermion mass is performed, either backward running or
an absence of running is observed at strong bare coupling. This behavior is
consistent with other findings which indicate that this theory has an infrared
fixed point.Comment: 12 pages, 3 figures; v2 fifth mass point added, three extrapolations
now performed, conclusions softene
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