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bstract
Primordial SU(2) gauge fields with an isotropic background lead to the production of spin-2 particles during inflation. We provide a unified formalism to compute this effect in all of the ...inflation models with isotropic SU(2) gauge fields such as Gauge-flation and Chromo-Natural inflation with and without spectator axion fields or the mass of the gauge field from the Higgs mechanism. First, we calculate the number and energy densities of the spin-2 particles. We then obtain exact analytical formulae for their backreaction on the background equations of motion of SU(2) and axion fields in (quasi) de Sitter expansion, which were calculated only numerically for one particular model in the literature. We show that the backreaction is directly related to the number density of the spin-2 field. Second, we relate the number density of the spin-2 particles to the power spectrum and the energy density of the gravitational waves sourced by them. Finally, we use the size of the backreaction to constrain the parameter space of the models. We find that the tensor-to-scalar ratio of the sourced gravitational waves can at most be on the order of that of the vacuum contribution to avoid a large backreaction on slow-roll dynamics of the gauge ssand axion fields in quasi-de Sitter expansion.
We calculate the one-point probability density distribution functions (PDF) and the power spectra of the thermal and kinetic Sunyaev-Zeldovich (tSZ and kSZ) effects and the mean Compton Y parameter ...using the Magneticum Pathfinder simulations, state-of-the-art cosmological hydrodynamical simulations of a large cosmological volume of (896 Mpc h super( -1)) super( 3). These simulations follow in detail the thermal and chemical evolution of the intracluster medium as well as the evolution of supermassive black holes and their associated feedback processes. We construct full-sky maps of tSZ and kSZ from the light-cones out to z = 0.17, and one realization of 8 ...8 x 8 ...8 deep light-cone out to z = 5.2. The local universe at z < 0.027 is simulated by a constrained realization. The tail of the one-point PDF of tSZ from the deep light-cone follows a power-law shape with an index of -3.2. Once convolved with the effective beam of Planck, it agrees with the PDF measured by Planck. The predicted tSZ power spectrum agrees with that of the Planck data at all multipoles up to l ... 1000, once the calculations are scaled to the Planck 2015 cosmological parameters with ... = 0.308 and ... = 0.8149. Consistent with the results in the literature, however, we continue to find the tSZ power spectrum at l = 3000 that is significantly larger than that estimated from the high-resolution ground-based data. The simulation predicts the mean fluctuating Compton Y value of Y = 1.18 x 10 super( -6) for ... = 0.272 and ... = 0.809. Nearly half (...5 x 10 super( -7)) of the signal comes from haloes below a virial mass of 10 super( 13) M... h super( -1). Scaling this to the Planck 2015 parameters, we find Y = 1.57 x 10 super( -6). (ProQuest: ... denotes formulae/symbols omitted.)
ABSTRACT
The repair of a fractured bone is critical to the well‐being of humans. Failure of the repair process to proceed normally can lead to complicated fractures, exemplified by either a delay in ...union or a complete nonunion. Both of these conditions lead to pain, the possibility of additional surgery, and impairment of life quality. Additionally, work productivity decreases, income is reduced, and treatment costs increase, resulting in financial hardship. Thus, developing effective treatments for these difficult fractures or even accelerating the normal physiological repair process is warranted. Accumulating evidence shows that microRNAs (miRNAs), small noncoding RNAs, can serve as key regulatory molecules of fracture repair. In this review, a brief description of the fracture repair process and miRNA biogenesis is presented, as well as a summary of our current knowledge of the involvement of miRNAs in physiological fracture repair, osteoporotic fractures, and bone defect healing. Further, miRNA polymorphisms associated with fractures, miRNA presence in exosomes, and miRNAs as potential therapeutic orthobiologics are also discussed. This is a timely review as several miRNA‐based therapeutics have recently entered clinical trials for nonskeletal applications and thus it is incumbent upon bone researchers to explore whether miRNAs can become the next class of orthobiologics for the treatment of skeletal fractures.
A
bstract
Non-Abelian gauge fields may exist during inflation. We study the Schwinger effect by an SU(2) gauge field coupled to a charged scalar doublet in a (quasi) de Sitter background and the ...possible backreaction of the generated charged particles on the homogeneous dynamics. Contrary to the Abelian U(1) case, we find that both the Schwinger pair production and the induced current decrease as the interaction strength increases. The reason for this suppression is the isotropic vacuum expectation value of the SU(2) field which generates a (three times) greater effective mass for the scalar field than the U(1). In the weak interaction limit, the above effect is negligible and both the SU(2) and U(1) cases exhibit a linear increase of the current and a constant conductivity with the interaction strength. We conclude that the Schwinger effect does not pose a threat to the dynamics of inflationary models involving an SU(2) gauge field.
Standardized consensus definitions for resistant and refractory cytomegalovirus (CMV) infections and diseases in transplant recipients were developed by the CMV Resistance Working Group of the CMV ...Drug Development Forum and are intended to be used in clinical trials.
Abstract
Despite advances in preventive strategies, cytomegalovirus (CMV) infection remains a major complication in solid organ and hematopoietic cell transplant recipients. CMV infection may fail to respond to commercially available antiviral therapies, with or without demonstrating genotypic mutation(s) known to be associated with resistance to these therapies. This lack of response has been termed “resistant/refractory CMV” and is a key focus of clinical trials of some investigational antiviral agents. To provide consistent criteria for future clinical trials and outcomes research, the CMV Resistance Working Group of the CMV Drug Development Forum (consisting of scientists, clinicians, regulatory officials, and industry representatives from the United States, Canada, and Europe) has undertaken establishing standardized consensus definitions of “resistant” and “refractory” CMV. These definitions have emerged from the Working Group’s review of the available virologic and clinical literature and will be subject to reassessment and modification based on results of future studies.
Context. The precise determination of the present-day expansion rate of the Universe, expressed through the Hubble constant H0, is one of the most pressing challenges in modern cosmology. Assuming ...flat ΛCDM, H0 inference at high redshift using cosmic microwave background data from Planck disagrees at the 4.4σ level with measurements based on the local distance ladder made up of parallaxes, Cepheids, and Type Ia supernovae (SNe Ia), often referred to as Hubble tension. Independent cosmological-model-insensitive ways to infer H0 are of critical importance. Aims. We apply an inverse distance ladder approach, combining strong-lensing time-delay distance measurements with SN Ia data. By themselves, SNe Ia are merely good indicators of relative distance, but by anchoring them to strong gravitational lenses we can obtain an H0 measurement that is relatively insensitive to other cosmological parameters. Methods. A cosmological parameter estimate was performed for different cosmological background models, both for strong-lensing data alone and for the combined lensing + SNe Ia data sets. Results. The cosmological-model dependence of strong-lensing H0 measurements is significantly mitigated through the inverse distance ladder. In combination with SN Ia data, the inferred H0 consistently lies around 73–74 km s−1 Mpc−1, regardless of the assumed cosmological background model. Our results agree closely with those from the local distance ladder, but there is a > 2σ tension with Planck results, and a ∼1.5σ discrepancy with results from an inverse distance ladder including Planck, baryon acoustic oscillations, and SNe Ia. Future strong-lensing distance measurements will reduce the uncertainties in H0 from our inverse distance ladder.
This is a review of models of inflation and of their predictions for the primordial non-Gaussianity in the density perturbations which are thought to be at the origin of structures in the Universe. ...Non-Gaussianity emerges as a key observable to discriminate among competing scenarios for the generation of cosmological perturbations and is one of the primary targets of present and future Cosmic Microwave Background satellite missions. We give a detailed presentation of the state-of-the-art of the subject of non-Gaussianity, both from the theoretical and the observational point of view, and provide all the tools necessary to compute at second order in perturbation theory the level of non-Gaussianity in any model of cosmological perturbations. We discuss the new wave of models of inflation, which are firmly rooted in modern particle physics theory and predict a significant amount of non-Gaussianity. The review is addressed to both astrophysicists and particle physicists and contains useful tables which summarize the theoretical and observational results regarding non-Gaussianity.
We present cosmological parameter constraints based on the final nine-year Wilkinson Microwave Anisotropy Probe (WMAP) data, in conjunction with a number of additional cosmological data sets. The ...WMAP data alone, and in combination, continue to be remarkably well fit by a six-parameter ?CDM model. We compare recent Planck measurements of the Sunyaev-Zel'dovich effect with our seven-year measurements, and show their mutual agreement. Our analysis of the polarization pattern around temperature extrema is updated. This confirms a fundamental prediction of the standard cosmological model and provides a striking illustration of acoustic oscillations and adiabatic initial conditions in the early universe.
We perform forecasts for how baryon acoustic oscillation (BAO) scale and redshift-space distortion (RSD) measurements from future spectroscopic emission line galaxy surveys such as Euclid are ...degraded in the presence of spectral line misidentification. Using analytic calculations verified with mock galaxy catalogs from lognormal simulations, we find that constraints are degraded in two ways, even when the interloper power spectrum is modeled correctly in the likelihood. First, there is a loss of signal-to-noise ratio for the power spectrum of the target galaxies, which propagates to all cosmological constraints and increases with contamination fraction, fc. Second, degeneracies can open up between fc and cosmological parameters. In our calculations, this typically increases BAO scale uncertainties at the 10%-20% level when marginalizing over parameters determining the broadband power spectrum shape. External constraints on fc or parameters determining the shape of the power spectrum, for example, from cosmic microwave background measurements, can remove this effect. There is a near-perfect degeneracy between fc and the power spectrum amplitude for low fc values, where fc is not well determined from the contaminated sample alone. This has the potential to strongly degrade RSD constraints. The degeneracy can be broken with an external constraint on fc, for example, from cross-correlation with a separate galaxy sample containing the misidentified line or deeper subsurveys.
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