Reconstruction Analysis of Galaxy Redshift Surveys: A Hybrid Reconstruction Method

In reconstruction analysis of galaxy redshift surveys, one works backwards from the observed galaxy distribution to the primordial density field in the same region, then evolves the primordial fluctuations forward in time with an N-body code. This incorporates assumptions about the cosmological parameters, the properties of primordial fluctuations, and the biasing relation between galaxies and mass. These can be tested by comparing the reconstruction to the observed galaxy distribution, and to peculiar velocity data. This paper presents a hybrid reconstruction method that combines the `Gaussianization'' technique of Weinberg(1992) with the dynamical schemes of Nusser & Dekel(1992) and Gramann(1993). We test the method on N-body simulations and on N-body mock catalogs that mimic the depth and geometry of the Point Source Catalog Redshift Survey and the Optical Redshift Survey. This method is more accurate than Gaussianization or dynamical reconstruction alone. Matching the observed morphology of clustering can limit the bias factor b, independent of Omega. Matching the cluster velocity dispersions and z-space distortions of the correlation function xi(s,mu) constrains the parameter beta=Omega^{0.6}/b. Relative to linear or quasi-linear approximations, a fully non-linear reconstruction makes more accurate predictions of xi(s,mu) for a given beta, thus reducing the systematic biases of beta measurements and offering further scope for breaking the degeneracy between Omega and b. It also circumvents the cosmic variance noise that limits conventional analyses of xi(s,mu). It can also improve the determination of Omega and b from joint analyses of redshift & peculiar velocity surveys as it predicts the fully non-linear peculiar velocity distribution at each point in z-space.Comment: 72 pages including 33 figures, submitted to Ap

Uncertainties in long-term twenty-first century process-based coastal sea-level projections

Many processes affect sea level near the coast. In this paper, we discuss the major uncertainties in coastal sea-level projections from a process-based perspective, at different spatial and temporal scales, and provide an outlook on how these uncertainties may be reduced. Uncertainty in centennial global sea-level rise is dominated by the ice sheet contributions. Geographical variations in projected sea-level change arise mainly from dynamical patterns in the ocean response and other geophysical processes. Finally, the uncertainties in the short-duration extreme sea-level events are controlled by near coastal processes, storms and tides

More than sense of place? Exploring the emotional dimension of rural tourism experiences

It is widely suggested that participation in rural tourism is underpinned by a sense of rural place or “rurality”. However, although nature and the countryside have long been recognised as a source of spiritual or emotional fulfilment, few have explored the extent to which tourism, itself often claimed to be a sacred experience, offers an emotional/spiritual dimension in the rural context. This paper addresses that literature gap. Using in-depth interviews with rural tourists in the English Lake District, it explores the extent to which, within respondents’ individual understanding of spirituality, a relationship exists between sense of place and deeper, emotional experiences and, especially, whether participation in rural tourism may induce spiritual or emotional responses. The research revealed that all respondents felt a strong attachment to the Lake District; similarly, and irrespective of their openness to spirituality, engaging in rural tourism activities resulted in highly emotive experiences for all respondents, the description/interpretation of such experiences being determined by individual “beliefs”. However, sense of place was not a prerequisite to emotional or spiritual experiences. Being in and engaging with the landscape � effectively becoming part of it � especially through physical activity is fundamental to emotional responses

Phase coherence phenomena in superconducting films

Superconducting films subject to an in-plane magnetic field exhibit a gapless superconducting phase. We explore the quasi-particle spectral properties of the gapless phase and comment on the transport properties. Of particular interest is the sensitivity of the quantum interference phenomena in this phase to the nature of the impurity scattering. We find that films subject to columnar defects exhibit a `Berry-Robnik' symmetry which changes the fundamental properties of the system. Furthermore, we explore the integrity of the gapped phase. As in the magnetic impurity system, we show that optimal fluctuations of the random impurity potential conspire with the in-plane magnetic field to induce a band of localized sub-gap states. Finally, we investigate the interplay of the proximity effect and gapless superconductivity in thin normal metal-superconductor bi-layers.Comment: 13 pages, 8 figures include

Influence of the confinement geometry on surface superconductivity

The nucleation field for surface superconductivity, $H_{c3}$, depends on the geometrical shape of the mesoscopic superconducting sample and is substantially enhanced with decreasing sample size. As an example we studied circular, square, triangular and wedge shaped disks. For the wedge the nucleation field diverges as $H_{c3}/H_{c2}=\sqrt{3}/\alpha$ with decreasing angle ($\alpha$) of the wedge, where $H_{c2}$ is the bulk upper critical field.Comment: 4 pages, 3 figures. Accepted for publication in Phys. Rev.

Effects of mesenchymal stromal cells versus serum on tendon healing in a controlled experimental trial in an equine model

Abstract Background Mesenchymal stromal cells (MSC) have shown promising results in the treatment of tendinopathy in equine medicine, making this therapeutic approach seem favorable for translation to human medicine. Having demonstrated that MSC engraft within the tendon lesions after local injection in an equine model, we hypothesized that they would improve tendon healing superior to serum injection alone. Methods Quadrilateral tendon lesions were induced in six horses by mechanical tissue disruption combined with collagenase application 3 weeks before treatment. Adipose-derived MSC suspended in serum or serum alone were then injected intralesionally. Clinical examinations, ultrasound and magnetic resonance imaging were performed over 24 weeks. Tendon biopsies for histological assessment were taken from the hindlimbs 3 weeks after treatment. Horses were sacrificed after 24 weeks and forelimb tendons were subjected to macroscopic and histological examination as well as analysis of musculoskeletal marker expression. Results Tendons injected with MSC showed a transient increase in inflammation and lesion size, as indicated by clinical and imaging parameters between week 3 and 6 (p < 0.05). Thereafter, symptoms decreased in both groups and, except that in MSC-treated tendons, mean lesion signal intensity as seen in T2w magnetic resonance imaging and cellularity as seen in the histology (p < 0.05) were lower, no major differences could be found at week 24. Conclusions These data suggest that MSC have influenced the inflammatory reaction in a way not described in tendinopathy studies before. However, at the endpoint of the current study, 24 weeks after treatment, no distinct improvement was observed in MSC-treated tendons compared to the serum-injected controls. Future studies are necessary to elucidate whether and under which conditions MSC are beneficial for tendon healing before translation into human medicine

Tightness of slip-linked polymer chains

We study the interplay between entropy and topological constraints for a polymer chain in which sliding rings (slip-links) enforce pair contacts between monomers. These slip-links divide a closed ring polymer into a number of sub-loops which can exchange length between each other. In the ideal chain limit, we find the joint probability density function for the sizes of segments within such a slip-linked polymer chain (paraknot). A particular segment is tight (small in size) or loose (of the order of the overall size of the paraknot) depending on both the number of slip-links it incorporates and its competition with other segments. When self-avoiding interactions are included, scaling arguments can be used to predict the statistics of segment sizes for certain paraknot configurations.Comment: 10 pages, 6 figures, REVTeX

Formation and structure of halos in a warm dark matter cosmology

(Abridged) Using high-resolution cosmological N-body simulations, we study how the density profiles of dark matter halos are affected by the filtering of the density power spectrum below a given scale length and by the introduction of a thermal velocity dispersion. In the warm dark matter (WDM) scenario, both the free-streaming scale, R_f, and the velocity dispersion, v_w, are determined by the mass m_w of the WDM particle. We find that v_w is too small to affect the density profiles of WDM halos. Down to the resolution attained in our simulations, there is not any significant difference in the density profiles and concentrations of halos obtained in simulations with and without the inclusion of v_w. The density profiles of halos with masses down to ~0.01 the filtering mass M_f can be described by the NFW shape; significant soft cores are not formed. Nevertheless, the concentrations of these halos are lower than those of the CDM counterparts and are approximately independent of mass. The lower concentrations of WDM halos with respect to their CDM counterparts can be accounted for their late formation epoch. Overall, our results point to a series of advantages of a WDM model over the CDM one. In addition to solving the substructure problem, a WDM model with R_f~0.16 Mpc (m_w~0.75 kev; flat cosmology with Omega_L=h=0.7) also predicts concentrations, a Tully-Fisher relation, and formation epochs for small halos which seems to be in better agreement with observations, relative to CDM predictions.Comment: Accepted for publication in ApJ. 34 pages, figs. 1a,1b, and 1c given in separate files (high resolution versions available at ftp://ftp.astroscu.unam.mx/pub/temporal/). Major modifications after referees Report (more simulations and new figures are presented), but main conclusions remain the sam

Topical or oral antibiotics for children with acute otitis media presenting with ear discharge: study protocol of a randomised controlled non-inferiority trial

BACKGROUND: Around 15%-20% of children with acute otitis media present with ear discharge due to a spontaneous tear or perforation of the eardrum (AOMd). Current guidance recommends clinicians to consider oral antibiotics as first-line treatment in this condition. The opening in the eardrum however should allow topical antibiotics to enter the middle ear directly. Local administration of antibiotics does not expose children to systemic side effects and may put less selective resistance pressure on bacteria. Evidence on the effectiveness of this approach in children with AOMd is lacking. METHODS AND ANALYSIS: A primary care-based, open, individually randomised, controlled, non-inferiority trial. The trial aims to recruit 350 children aged 6 months to 12 years with AOMd and ear pain and/or fever. Participants will be randomised to 7 days of hydrocortisone-bacitracin-colistin eardrops five drops three times daily or amoxicillin oral suspension 50 mg/kg body weight per day, divided over three doses. Parents will keep a daily diary of AOM symptoms, adverse events and complications for 2 weeks. In addition, they will record AOM recurrences, healthcare utilisation and societal costs for 3 months. The primary outcome is the proportion of children without ear pain and fever at day 3. Secondary outcomes include ear pain and fever intensity/severity; days with ear discharge; eardrum perforation at 2 weeks; adverse events during first 2 weeks; costs; and cost effectiveness at 2 weeks and 3 months. The primary analyses will be intention-to-treat and per-protocol analyses will be conducted as well. ETHICS AND DISSEMINATION: The medical research ethics committee Utrecht, The Netherlands has given ethical approval (17-400/G-M). Parents/guardians of participants will provide written informed consent. Study results will be submitted for publication in peer-reviewed medical journals and presented at relevant (inter)national scientific meetings. TRIAL REGISTRATION NUMBER: The Netherlands National Trial Register; NTR6723. Date of registration: 27 November 2017

A New Interpretation of Flux Quantization

We study the effect of Aharonov-Bohm flux on the superconducting state in metallic cylinders. Although Byers and Yang attributed flux quantization to the flux-dependent minimum of kinetic energies of the Cooper pairs, it is shown that kinetic energies do not produce any discernible oscillations in the free energy of the superconducting state (relative to that of normal state) as a function of the flux. This result is indeed anticipated by the observation of persistent current in normal metal rings at low temperature. Instead, we have found that pairing interaction depends on the flux, leading to flux quantization. When the flux $(\Phi$) is given by $\Phi=n\times hc/2e$ (with integer n), the pairing interaction and the free energy become unchanged (even n) or almost unchanged (odd n), due to degenerate-state pairing resulting from the energy level crossing. As a result, flux quantization and Little-Parks oscillations follow.Comment: Revtex, 10 pages, 6 figures, For more information, send me an e-mail at [email protected]