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Closing in on Omega(M): The amplitude of mass fluctuations from galaxy clusters and the Ly alpha forest
We estimate the present-day value of the matter density parameter ΩM by combining constraints from the galaxy cluster mass function with Croft et al.\u27s recent measurement of the mass power spectrum, P(k), from Lyα forest data. The key assumption of the method is that cosmic structure formed by gravitational instability from Gaussian primordial fluctuations. For a specified value of ΩM, matching the observed cluster mass function then fixes the value of σ8, the rms amplitude of mass fluctuations in 8 h-1 Mpc spheres, and it thus determines the normalization of P(k) at z = 0. The value of ΩM also determines the ratio of P(k) at z = 0 to P(k) at z = 2.5, the central redshift of the Lyα forest data; the ratio is different for an open universe (Λ = 0) or a flat universe. Because the Lyα forest measurement only reaches comoving scales 2π/k ~ 15-20 h-1 Mpc, the derived value of ΩM depends on the value of the power spectrum shape parameter Γ, which determines the relative contribution of larger scale modes to σ8. Adopting Γ = 0.2, a value favored by galaxy clustering data, we find ΩM = 0.46+0.12-0.10 for an open universe and ΩM = 0.34+0.13-0.09 for a flat universe (1 σ errors, not including the uncertainty in cluster normalization). Cluster-normalized models with ΩM = 1 predict too low an amplitude for P(k) at z = 2.5, while models with ΩM = 0.1 predict too high an amplitude. The more general best-fit parameter combination is ΩM + 0.2ΩΛ 0.46 + 1.3(Γ - 0.2), where ΩΛ ≡ Λ/3H20. Analysis of larger, existing samples of QSO spectra could greatly improve the measurement of P(k) from the Lyα forest, allowing a determination of ΩM by this method with a precision of ~15%, limited mainly by uncertainty in the cluster mass function
Constraints on cosmological parameters from the Ly alpha forest power spectrum and COBE DMR
We combine COBE DMR measurements of cosmic microwave background (CMB) anisotropy with a recent measurement of the mass power spectrum at redshift z = 2.5 from Lyα forest data to derive constraints on cosmological parameters and test the inflationary cold dark matter (CDM) scenario of structure formation. By treating the inflationary spectral index n as a free parameter, we are able to find successful fits to the COBE and Lyα forest constraints in Ωm = 1 models with and without massive neutrinos and in low-Ωm models with and without a cosmological constant. Within each class of model, the combination of COBE and the Lyα forest P(k) constrains a parameter combination of the form ΩmhαnβΩ, with different indices for each case. This new constraint breaks some of the degeneracies in cosmological parameter determinations from other measurements of large-scale structure and CMB anisotropy. The Lyα forest P(k) provides the first measurement of the slope of the linear mass power spectrum on ~Mpc scales, ν = -2.25 ± 0.18, and it confirms a basic prediction of the inflationary CDM scenario: an approximately scale invariant spectrum of primeval fluctuations (n 1) modulated by a transfer function that bends P(k) toward kn-4 on small scales. Considering additional observational data, we find that COBE-normalized, Ωm = 1 models that match the Lyα forest P(k) do not match the observed masses of rich galaxy clusters, and that low-Ωm models with a cosmological constant provide the best overall fit to the available data, even without the direct evidence for cosmic acceleration from Type Ia supernovae. With our fiducial parameter choices, the flat, low-Ωm models that match COBE and the Lyα forest P(k) also match recent measurements of small-scale CMB anisotropy. Modest improvements in the Lyα forest P(k) measurement could greatly restrict the allowable region of parameter space for CDM models, constrain the contribution of tensor fluctuations to CMB anisotropy, and achieve a more stringent test of the current consensus model of structure formation
Raznolikost starohrvatskog nazivlja za alge i za pomorsku prirodu na jadranskim otocima
By a consistent registering of vernacular names for algae, we have documented 156 marine phytonyms along eastern Adriatic for macroalgae and Zosteraceae, including a half of local synonyms between different islands and mainland areas, and 82 names for different marine taxa. Therefore Croatian vernacular names of marine algae are the most numerous within Europe, their richness being subequal to the maximal one for Japanese algae. A minor amount of these marine phytonyms are Romanic loans (1/5 to 1/3), half of them are of Slavonic origin, and the rest are pre-Romance-non-Slavic archaisms of early Liburnian and Proto-Indo-European origin. The poorest stock of algal names occurs in the Dalmatian mainland with 9 Shtokavian phytonyms, and the more abundant Chakavian ones we have registered in the islands: the richest ones in southeastern Krk with 79 marine phytonyms, 25 in Rab, 19 in Dugi Otok, 15 in Vis, 12 in @irje island, and the poorest are Mljet and Lastovo islands and the Velebit coast with 3–5 marine phytonyms.Sustavnim popisom je kod nas na istočnom Jadranu nadjeno 156 morskih fitonima za makroalge i Zosteraceae, od čega su polovica sinonimi između raznih otoka i kopna, a ostalih 82 fitonima se odnose na posebne morske svojte. Zato su kod nas imena morskih alga bogatija negoli igdje u Europi i podjednako brojna kao u najbogatijem svjetskom nazivlju za alge u Japanu. Tek manji dio toga hrvatskog nazivlja za alge su posudjeni romanizmi (1/5–1/3), polovica su čakavski nazivi, a ostalo predromansko-neslavenski arhaizmi liburno-ilirskoga i praindoeuropskog podrijetla. Kod nas je najsiromašnije štokavsko nazivlje alga na kopnenim obalama, najviše do 9 fitonima. Bogatije je čakavsko nazivlje alga na otocima: najviše je 79 morskih fitonima na jugoistočnom Krku, pa 25 na Rabu, 19 na Dugom otoku, 15 na Visu, 12 na Žirju, a najmanje (3–5) velebitska obala, Mljet i Lastovo
The extraction of antioxidative compounds from rusks enriched with millet flour (Panicum miliaceum L.)
Two different ways of extracting antioxidative compounds (including soluble polyphenols) from rusks made from wheat flour with added millet (Panicum miliaceum L.) were compared, i.e., solvent extraction and in vitro digestion. Wheat flour was replaced by millet flour in amounts of 10, 20 or 30 wt. % (per dry mass). Solvent extraction was realized using a mixture of ethanol and water in different percentages, with or without the addition of formic acid. The total content of phenolic compounds (TPC) was determined using Folin-Ciocalteu reagent, while the antioxidative capacity was measured by the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The efficiency of solvent extraction was enhanced by the addition of formic acid. The addition of millet flour in amounts up to 20 % enhanced the antioxidative properties. It was shown that in vitro digestion was more efficient in the extraction of antioxidative compounds, in comparison with solvent extraction
LASER in periodontal treatment: is it an effective treatment or science fiction?
There are several studies that evaluate the use of lasers in periodontal treatment in non-surgical or surgical therapy. However, while several studies showed clinically beneficial effects of some lasers in periodontal treatment, there are few clinical reports of additional advantages of lasers as adjunctive treatments in periodontology. The aim of this paper is to demonstrate and critically analyze the level of scientific evidence of effects of low-level lasers and high-power lasers in periodontology. A narrative review of the studies was carried out in each topic and type of laser or periodontal treatment. In nonsurgical periodontal therapy the results showed that there is an additional clinical benefit when using a diode laser (DL) associated with scaling and root planing (SRP) in patients with moderate to severe periodontitis. The Er:YAG laser seems to be the most suitable for nonsurgical periodontal therapy and promotes the same clinical effects as conventional therapy. In periodontal surgery vaporization of the gingival or mucosal tissue can be carried out with DL, CO2, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers. Photobiomodulation (PBM), mediated by low-level lasers associated with non-surgical periodontal therapy, promotes additional benefits in the short term and accelerates the bone and gingival tissue repair process and also reduces postoperative symptoms of periodontal surgery. The effect of antimicrobial Photodynamic Therapy is relevant in the initial reevaluation periods. Studies have shown controversial results of the use of lasers in periodontics, and this fact may be due to the lack of standard parameters of irradiation in each clinical application
Universality in Systems with Power-Law Memory and Fractional Dynamics
There are a few different ways to extend regular nonlinear dynamical systems
by introducing power-law memory or considering fractional
differential/difference equations instead of integer ones. This extension
allows the introduction of families of nonlinear dynamical systems converging
to regular systems in the case of an integer power-law memory or an integer
order of derivatives/differences. The examples considered in this review
include the logistic family of maps (converging in the case of the first order
difference to the regular logistic map), the universal family of maps, and the
standard family of maps (the latter two converging, in the case of the second
difference, to the regular universal and standard maps). Correspondingly, the
phenomenon of transition to chaos through a period doubling cascade of
bifurcations in regular nonlinear systems, known as "universality", can be
extended to fractional maps, which are maps with power-/asymptotically
power-law memory. The new features of universality, including cascades of
bifurcations on single trajectories, which appear in fractional (with memory)
nonlinear dynamical systems are the main subject of this review.Comment: 23 pages 7 Figures, to appear Oct 28 201
Multimodal characterization of the visual network in Huntington's disease gene carriers
Objective
A sensorimotor network structural phenotype predicted motor task performance in a previous study in Huntington’s disease (HD) gene carriers. We investigated in the visual network whether structure – function – behaviour relationship patterns, and the effects of the HD mutation, extended beyond the sensorimotor network.
Methods
We used multimodal visual network MRI structural measures (cortical thickness and white matter connectivity), plus visual evoked potentials and task performance (Map Search; Symbol Digit Modalities Test) in healthy controls and HD gene carriers.
Results
Using principal component (PC) analysis, we identified a structure – function relationship common to both groups. PC scores differed between groups indicating white matter disorganization (higher RD, lower FA) and slower, and more disperse, VEP signal transmission (higher VEP P100 latency and lower VEP P100 amplitude) in HD than controls while task performance was similar.
Conclusions
HD may be associated with reduced white matter organization and efficient visual network function but normal task performance.
Significance
These findings indicate that structure – function relationships in the visual network, and the effects of the HD mutation, share some commonalities with those in the sensorimotor network. However, implications for task performance differ between the two networks suggesting the influence of network specific factors
Direct and Inverse Variational Problems on Time Scales: A Survey
We deal with direct and inverse problems of the calculus of variations on
arbitrary time scales. Firstly, using the Euler-Lagrange equation and the
strengthened Legendre condition, we give a general form for a variational
functional to attain a local minimum at a given point of the vector space.
Furthermore, we provide a necessary condition for a dynamic
integro-differential equation to be an Euler-Lagrange equation (Helmholtz's
problem of the calculus of variations on time scales). New and interesting
results for the discrete and quantum settings are obtained as particular cases.
Finally, we consider very general problems of the calculus of variations given
by the composition of a certain scalar function with delta and nabla integrals
of a vector valued field.Comment: This is a preprint of a paper whose final and definite form will be
published in the Springer Volume 'Modeling, Dynamics, Optimization and
Bioeconomics II', Edited by A. A. Pinto and D. Zilberman (Eds.), Springer
Proceedings in Mathematics & Statistics. Submitted 03/Sept/2014; Accepted,
after a revision, 19/Jan/201
Inter-individual relationships within a Canadian SPOR research network: a social network study
Efforts have been made by health research granting agencies to bring research closer to patients’ concerns. In Canada, such efforts were formalized in 2011 with the funding of the Strategy for Patient-Oriented Research (SPOR)’s research networks to address research priorities identified by patients and accelerate the translation of research findings into patient care and health care policy. Among these networks, SPOR Diabetes Action Canada (DAC) has created patient-partner circles to facilitate their integration within the network. The nature of the relationships within this atypical patient-oriented research network is systematically explored in this paper
Trends in Students Media Usage
Trends in media usage by students can affect the way they learn. Students demand the use of technology, thus institutions and instructors should meet students’ requests. This paper describes the results of a survey where drivers in the use of media show continuously increasing or decreasing values from the first to the fourth year of study experience at the Western University, Canada, highlighting trends in the usage of new and traditional media in higher education by students. The survey was used to gather data on students’ media usage habits and user satisfaction from first to fourth year of study and found that media usage increases over the years from first to fourth. The presentation of data using bar charts reveals a slight increase over the years in students owning notebooks or laptops off-campus and a significant increase from first to fourth year of students accessing online academic periodicals and journals. Another noteworthy finding relates to fourth year students being more conscious of the quality of information that they read on the Internet in comparison to students in first year, even though this is a slight year on year increase
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