Limits on the parameters of the equation of state for interacting dark energy

Under the assumption that cold dark matter and dark energy interact with each other through a small coupling term, $Q$, we constrain the parameter space of the equation of state $w$ of those dark energy fields whose variation of the field since last scattering do not exceed Planck's mass. We use three parameterizations of $w$ and two different expressions for $Q$. Our work extends previous ones.Comment: 18 pages, 11 figures, accepted for publication on Physics Letters

Modulating attentional load affects numerosity estimation: evidence against a pre-attentive subitizing mechanism

Traditionally, the visual enumeration of a small number of items (1 to about 4), referred to as subitizing, has been thought of as a parallel and pre-attentive process and functionally different from the serial attentive enumeration of larger numerosities. We tested this hypothesis by employing a dual task paradigm that systematically manipulated the attentional resources available to an enumeration task. Enumeration accuracy for small numerosities was severely decreased as more attentional resources were taken away from the numerical task, challenging the traditionally held notion of subitizing as a pre-attentive, capacity-independent process. Judgement of larger numerosities was also affected by dual task conditions and attentional load. These results challenge the proposal that small numerosities are enumerated by a mechanism separate from large numerosities and support the idea of a single, attention-demanding enumeration mechanism

Kinetic k-essence ghost dark energy model

A ghost dark energy model has been recently put forward to explain the current accelerated expansion of the Universe. In this model, the energy density of ghost dark energy, which comes from the Veneziano ghost of QCD, is proportional to the Hubble parameter, $\rho_D=\alpha H$. Here $\alpha$ is a constant of order $\Lambda^3_{QCD}$ where $\Lambda_{QCD}\sim 100 MeV$ is the QCD mass scale. We consider a connection between ghost dark energy with/without interaction between the components of the dark sector and the kinetic k-essence field. It is shown that the cosmological evolution of the ghost dark energy dominated Universe can be completely described a kinetic k-essence scalar field. We reconstruct the kinetic k-essence function $F(X)$ in a flat Friedmann-Robertson-Walker Universe according to the evolution of ghost dark energy density.Comment: 11 pages, 15 figures, some clarifications added in the introduction, added references. Accepted for publication in Phys. Lett.

Cosmic age problem revisited in the holographic dark energy model

Because of an old quasar APM 08279+5255 at $z=3.91$, some dark energy models face the challenge of the cosmic age problem. It has been shown by Wei and Zhang [Phys. Rev. D {\bf 76}, 063003 (2007)] that the holographic dark energy model is also troubled with such a cosmic age problem. In order to accommodate this old quasar and solve the age problem, we propose in this Letter to consider the interacting holographic dark energy in a non-flat universe. We show that the cosmic age problem can be eliminated when the interaction and spatial curvature are both involved in the holographic dark energy model.Comment: 7 pages, 3 figures; v2: typos corrected, version for publication in Phys.Lett.B; v3: typos in eqs (17,18) correcte

Temporal Brain Dynamics of Multiple Object Processing: The Flexibility of Individuation

The ability to process concurrently multiple visual objects is fundamental for a coherent perception of the world. A core component of this ability is the simultaneous individuation of multiple objects. Many studies have addressed the mechanism of object individuation but it remains unknown whether the visual system mandatorily individuates all relevant elements in the visual field, or whether object indexing depends on task demands. We used a neural measure of visual selection, the N2pc component, to evaluate the flexibility of multiple object individuation. In three ERP experiments, participants saw a variable number of target elements among homogenous distracters and performed either an enumeration task (Experiment 1) or a detection task, reporting whether at least one (Experiment 2) or a specified number of target elements (Experiment 3) was present. While in the enumeration task the N2pc response increased as a function of the number of targets, no such modulation was found in Experiment 2, indicating that individuation of multiple targets is not mandatory. However, a modulation of the N2pc similar to the enumeration task was visible in Experiment 3, further highlighting that object individuation is a flexible mechanism that binds indexes to object properties and locations as needed for further object processing

Nanosecond motions in proteins impose bounds on the timescale distributions of local dynamics

We elucidate the physics of the dynamical transition via 10-100ns molecular dynamics simulations at temperatures spanning 160-300K. By tracking the energy fluctuations, we show that the protein dynamical transition is marked by a cross-over from piecewise stationary to stationary processes that underlie the dynamics of protein motions. A two-time-scale function captures the non-exponential character of backbone structural relaxations. One is attributed to the collective segmental motions and the other to local relaxations. The former is well-defined by a single-exponential, nanosecond decay, operative at all temperatures. The latter is described by a set of processes that display a distribution of time-scales. Though their average remains on the picosecond time-scale, the distribution is markedly contracted at the onset of the transition. The collective motions are shown to impose bounds on time-scales spanned by local dynamical processes. The piecewise stationary character below the transition implicates the presence of a collection of sub-states whose interactions are restricted. At these temperatures, a wide distribution of local motion time-scales, extending beyond that of nanoseconds is observed. At physiological temperatures, local motions are confined to time-scales faster than nanoseconds. This relatively narrow window makes possible the appearance of multiple channels for the backbone dynamics to operate.Comment: 26 pages, 9 figures; suplementary materials adde

The association of RANTES polymorphism with severe acute respiratory syndrome in Hong Kong and Beijing Chinese

<p>Abstract</p> <p>Background</p> <p>Chemokines play important roles in inflammation and antiviral action. We examined whether polymorphisms of <it>RANTES, IP-10 </it>and <it>Mig </it>affect the susceptibility to and outcome of severe acute respiratory syndrome (SARS).</p> <p>Methods</p> <p>We tested the polymorphisms of <it>RANTES, IP-10 </it>and <it>Mig </it>for their associations with SARS in 495 Hong Kong Chinese SARS patients and 578 controls. Then we tried to confirm the results in 356 Beijing Chinese SARS patients and 367 controls.</p> <p>Results</p> <p><it>RANTES </it>-28 G allele was associated with SARS susceptibility in Hong Kong Chinese (<it>P </it>< 0.0001, OR = 2.80, 95%CI:2.11–3.71). Individuals with <it>RANTES </it>-28 CG and GG genotypes had a 3.28-fold (95%CI:2.32–4.64) and 3.06-fold (95%CI:1.47–6.39) increased risk of developing SARS respectively (<it>P </it>< 0.0001). This -28 G allele conferred risk of death in a gene-dosage dependent manner (<it>P </it>= 0.014) with CG and GG individuals having a 2.12-fold (95% CI: 1.11–4.06) and 4.01-fold (95% CI: 1.30–12.4) increased risk. For the replication of <it>RANTES </it>data in Beijing Chinese, the -28 G allele was not associated with susceptibility to SARS. However, -28 CG (OR = 4.27, 95%CI:1.64–11.1) and GG (OR = 3.34, 95%CI:0.37–30.7) were associated with admission to intensive care units or death due to SARS (<it>P </it>= 0.011).</p> <p>Conclusion</p> <p><it>RANTES </it>-28 G allele plays a role in the pathogenesis of SARS.</p

Comorbidity of Common Mental Disorders with Cancer and Their Treatment Gap: Findings from the World Mental Health Surveys

Objective This study aimed to study the comorbidity of common mental disorders (CMDs) and cancer, and the mental health treatment gap among community residents with active cancer, cancer survivors and cancer-free respondents in 13 high-income and 11 low-middle-income countries. Methods Data were derived from the World Mental Health Surveys (N = 66,387; n = 357 active cancer, n = 1373 cancer survivors, n = 64,657 cancer-free respondents). The World Health Organization/Composite International Diagnostic Interview was used in all surveys to estimate CMDs prevalence rates. Respondents were also asked about mental health service utilization in the preceding 12 months. Cancer status was ascertained by self-report of physician\u27s diagnosis. Results Twelve-month prevalence rates of CMDs were higher among active cancer (18.4%, SE = 2.1) than cancer-free respondents (13.3%, SE = 0.2) adjusted for sociodemographic confounders and other lifetime chronic conditions (adjusted odds ratio (AOR) = 1.44, 95% CI 1.05-1.97). CMD rates among cancer survivors (14.6%, SE = 0.9) compared with cancer-free respondents did not differ significantly (AOR = 0.95, 95% CI 0.82-1.11). Similar patterns characterized high-income and low-middle-income countries. Of respondents with active cancer who had CMD in the preceding 12 months, 59% sought services for mental health problems (SE = 5.3). The pattern of service utilization among people with CMDs by cancer status (highest among persons with active cancer, lower among survivors and lowest among cancer-free respondents) was similar in high-income (64.0%, SE = 6.0; 41.2%, SE = 3.0; 35.6%, SE = 0.6) and low-middle-income countries (46.4%, SE = 11.0; 22.5%, SE = 9.1; 17.4%, SE = 0.7). Conclusions Community respondents with active cancer have higher CMD rates and high treatment gap. Comprehensive cancer care should consider both factors

Reconstructing the interaction between the dark matter and holographic dark energy

We reconstruct the interaction rate between the dark matter and the holographic dark energy with the parameterized equation of states and the future event horizon as the infrared cut-off length. It is shown that the observational constraints from the 192 SNIa and BAO measurement permit the negative interaction in the wide region. Moreover, the usual phenomenological descriptions can not describe the reconstructed interaction well for many cases. The other possible interaction is also discussed.Comment: 9 pages, 2 table, 5 figures, revised version accepted for publication in Class. Quantum. Gra

Role of TGF-β1 haplotypes in the occurrence of myocardial infarction in young Italian patients

<p>Abstract</p> <p>Background</p> <p>Transforming growth factor beta 1 (TGF-β1) gene play an important role in the acute myocardial infarction (AMI), however no investigation has been conducted so far in young AMI patients.</p> <p>In this study, we evaluated the influence of TGF-β1 polymorphisms/haplotypes on the onset and progression of AMI in young Italian population.</p> <p>Methods</p> <p>201 cases and 201 controls were genotyped for three TGF-β1 polymorphisms (G-800A, C-509T and Leu10Pro). The main follow-up end-points (mean follow-up, 107 ± 49 months) were death, myocardial infarction or revascularization procedures.</p> <p>Results</p> <p>Significant risk factors were smoking (p < 10^-4), family history for coronary artery disease (p < 10^-4), hypercholesterolemia (p = 0.001) and hypertension (p = 0.002). The C-509T and Leu10Pro polymorphisms showed significant differences (p = 0.026 and p = 0.004) between cases and controls.</p> <p>The most common haplotypes revealed a possible protective effect (GCT, OR 0.75, 95% CI 0.57–0.99, p = 0.042) and an increased risk of AMI (GTC, OR 1.51, 95% CI 1.13–2.02, p = 0.005), respectively.</p> <p>No statistical differences were observed in genotype distribution in the follow-up study between the two groups: 61 patients with subsequent events (13 deaths) and 108 without events.</p> <p>Conclusion</p> <p>Even though our results need to be further confirmed in larger studies, this is the first study reporting on a possible role of TGFβ1 common haplotypes in the onset of AMI in young patients.</p