2,285 research outputs found
Note on Anomalous Higgs-Boson Couplings in Effective Field Theory
We propose a parametrization of anomalous Higgs-boson couplings that is both
systematic and practical. It is based on the electroweak chiral Lagrangian,
including a light Higgs boson, as the effective field theory (EFT) at the
electroweak scale . This is the appropriate framework for the case of
sizeable deviations in the Higgs couplings of order from the Standard
Model, considered to be parametrically larger than new-physics effects in the
sector of electroweak gauge interactions. The role of power counting in
identifying the relevant parameters is emphasized. The three relevant scales,
, the scale of new Higgs dynamics , and the cut-off ,
admit expansions in and . The former corresponds
to an organization of operators by their canonical dimension, the latter by
their loop order or chiral dimension. In full generality the EFT is thus
organized as a double expansion. However, as long as the EFT
systematics is closer to the chiral counting. The leading effects in the
consistent approximation provided by the EFT, relevant for the presently most
important processes of Higgs production and decay, are given by a few
(typically six) couplings. These parameters allow us to describe the properties
of the Higgs boson in a general and systematic way, and with a precision
adequate for the measurements to be performed at the LHC. The framework can be
systematically extended to include loop corrections and higher-order terms in
the EFT.Comment: 7 pages, no figures; typos corrected; references adde
Probing global aspects of a geometry by the self-force on a charge: Spherical thin-shell wormholes
The self-interaction for a static point charge in the space-time of a
thin-shell wormhole constructed connecting two identical Schwarzschild
geometries is calculated in a series expansion. The electrostatic self-force is
evaluated numerically. It is found to be attractive towards the throat except
for some values of the throat radius proximate to the value of the
Schwarzschild horizon for which the force is repulsive or attractive depending
on the position of the charge. The result differs from the self-force in the
space-time of the Schwarzschild black hole, where it is always repulsive from
the center. Although these wormhole and black hole geometries are locally
indistinguishable, the different topologies of both backgrounds are manifested
in the electrostatic field of a point charge.Comment: 17 pages, 4 figue
Viability of Pineapple Leaves as an Alternative Natural Fiber Geotextile
The study focuses on the utilization of pineapple leaves fiber as a raw material for the production of geotextiles. The fiber yarns were weaved based on required size of sample issued by the Philippines Textile Research Institute (PTRI) of the Department of Science and Technology (DOST). The Zwick/Roell Tensile Strength Tester Z050 (CRE) with 50 KN full scale load was used with the Wide-Width Strip Method in order to get the average tensile strength of the specimens each for both pineapple and abaca geotextile samples. The resulting average tensile strength and average nominal thickness for pineapple leaves geo-textile, when compared to abaca geo-textile has higher tensile force for a thinner sample of pineapple leaf geo-textile
Complete One-Loop Renormalization of the Higgs-Electroweak Chiral Lagrangian
Employing background-field method and super-heat-kernel expansion, we compute
the complete one-loop renormalization of the electroweak chiral Lagrangian with
a light Higgs boson. Earlier results from purely scalar fluctuations are
confirmed as a special case. We also recover the one-loop renormalization of
the conventional Standard Model in the appropriate limit.Comment: 15 pages, no figures; v2: reference and comments added, typos fixed,
matches published versio
Combining causal model and focus group discussions experiences learned from a socio-anthropological research on the differing perceptions of caretakers and health professionals on children's health (Bolivia/Peru)
The paper discusses the utility of constructing causal models in focus groups. This was experienced as a complement to an in-depth ethnographic research on the differing perceptions of caretakers and health professionals on child's growth and development in Peru and Bolivia. The rational, advantages, difficulties and necessary adaptations of combining the two techniques are discussed on the basis of concrete examples. Authors conclude that the building of a causal model in a focus group session can be useful in comparing lay etiologies of diseases as perceived by different categories of caretakers and health professionals and in identifying specific health risks faced by children. Causal model building in a focus group can help renew discussions and participants'interest but its use is only justified when the study concerns the perception of the causality of a given phenomenon
12CO and 13CO J=3-2 observations toward N11 in the Large Magellanic Cloud
After 30 Doradus, N11 is the second largest and brightest nebula in the LMC.
This large nebula has several OB associations with bright nebulae at its
surroundings. N11 was previously mapped at the lowest rotational transitions of
CO (J=1--0 and 2--1), and in some particular regions pointings of the
CO J=1--0 and 2--1 lines were also performed. Using ASTE we mapped the
whole extension of the N11 nebula in the CO J=3--2 line, and three
sub-regions in the CO J=3--2 line. The regions mapped in the CO
J=3--2 were selected based on that they may be exposed to the radiation at
different ways: a region lying over the nebula related to the OB association
LH10 (N11B), another one that it is associated with the southern part of the
nebula related to the OB association LH13 (N11D), and finally a farther area at
the southwest without any embedded OB association (N11I). We found that the
morphology of the molecular clouds lying in each region shows some signatures
that could be explained by the expansion of the nebulae and the action of the
radiation. Fragmentation generated in a molecular shell due to the expansion of
the N11 nebula is suggested. The integrated line ratios CO/CO
show evidences of selective photodissociation of the CO, and probably
other mechanisms such as chemical fractionation. The CO contribution to the
continuum at 870 m was directly derived. The distribution of the
integrated line ratios CO J=3--2/2--1 show hints of stellar feedback in
N11B and N11D. The ratio between the virial and LTE mass (M/M) is higher than unity in all analyzed molecular clumps, which suggests
that the clumps are not gravitationally bounded and may be supported by
external pressure. A non-LTE analysis suggests that we are mapping gas with
densities about a few 10 cm.Comment: Accepted to be published in A&A. Figures were degrade
Effects of exercise modalities on arterial stiffness and wave reflection: a systematic review and meta-analysis of randomized controlled trials
Background and Objectives:
Physical activity is associated with lower cardiovascular and all-cause mortality. However, the effects of different exercise modalities on arterial stiffness are currently unclear. Our objectives were to investigate the effects of exercise modalities (aerobic, resistance or combined) on pulse wave velocity (PWV) and augmentation index (AIx), and to determine whether the effects on these indices differed according to the participants' or exercise characteristics.
Methods:
We searched the Medline, Embase and Cochrane Library databases from inception until April 2014 for randomized controlled trials lasting ≥4 weeks investigating the effects of exercise modalities on PWV and AIx in adults aged ≥18 years.
Results:
Forty-two studies (1627 participants) were included in this analysis. Aerobic exercise improved both PWV (WMD: −0.63 m/s, 95% CI: −0.90, −0.35) and AIx (WMD:−2.63%, 95% CI: −5.25 to −0.02) significantly. Aerobic exercise training showed significantly greater reduction in brachial-ankle (WMD: −1.01 m/s, 95% CI: −1.57, −0.44) than in carotid-femoral (WMD: -0.39 m/s, 95% CI: −0.52, −0.27) PWV. Higher aerobic exercise intensity was associated with larger reductions in AIx (β: −1.55%, CI −3.09, 0.0001). In addition, aerobic exercise had a significantly larger effect in reducing PWV (WMD:−1.0 m/s, 95% CI: −1.43, −0.57) in participants with stiffer arteries (PWV ≥8 m/s). Resistance exercise had no effect on PWV and AIx. There was no significant effect of combined exercise on PWV and AIx.
Conclusions:
We conclude that aerobic exercise improved arterial stiffness significantly and that the effect was enhanced with higher aerobic exercise intensity and in participants with greater arterial stiffness at baseline.
Trial Registration PROSPERO:
Database registration: CRD42014009744,
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