Probing the magnetic ground state of the molecular Dysprosium triangle

We present zero field muon spin lattice relaxation measurements of a Dysprosium triangle molecular magnet. The local magnetic fields sensed by the implanted muons indicate the coexistence of static and dynamic internal magnetic fields below $T^* ~35$ K. Bulk magnetization and heat capacity measurements show no indication of magnetic ordering below this temperature. We attribute the static fields to the slow relaxation of the magnetization in the ground state of Dy3. The fluctuation time of the dynamic part of the field is estimated to be ~0.55 $\mu$s at low temperaturesComment: 5 pages, 5 figures, accepted for publication in Phys. Rev.

The Nonlinear Cosmological Matter Power Spectrum with Massive Neutrinos I: The Halo Model

Measurements of the linear power spectrum of galaxies have placed tight constraints on neutrino masses. We extend the framework of the halo model of cosmological nonlinear matter clustering to include the effect of massive neutrino infall into cold dark matter (CDM) halos. The magnitude of the effect of neutrino clustering for three degenerate mass neutrinos with m_nu=0.9 eV is of order ~1%, within the potential sensitivity of upcoming weak lensing surveys. In order to use these measurements to further constrain--or eventually detect--neutrino masses, accurate theoretical predictions of the nonlinear power spectrum in the presence of massive neutrinos will be needed, likely only possible through high-resolution multiple particle (neutrino, CDM and baryon) simulations.Comment: v2: matches PRD versio

Distibusi Bivalvia (Moluska) Di Danau Sipogas Kabupaten Rokan Hulu Provinsi Riau

The aims of this study was to determine distribution of Bivalvia (Mollusca) in Sipogas Lake Rokan Hulu Regency, Riau Province. The study was conducted in November to December 2014 with survey method. Sample collected by using eckman dredge with purposive random sampling, with four stations. Results showed, 1 species was found, it was Corbicula javanica with a total number of 77 individuals. The density was ranged from 17.78 to 64 individuals/m2, with distribution patterns on pattern of grouped distribution

Precise Particle Tracking Against a Complicated Background: Polynomial Fitting with Gaussian Weight

We present a new particle tracking software algorithm designed to accurately track the motion of low-contrast particles against a background with large variations in light levels. The method is based on a polynomial fit of the intensity around each feature point, weighted by a Gaussian function of the distance from the centre, and is especially suitable for tracking endogeneous particles in the cell, imaged with bright field, phase contrast or fluorescence optical microscopy. Furthermore, the method can simultaneously track particles of all different sizes, and allows significant freedom in their shape. The algorithm is evaluated using the quantitative measures of accuracy and precision of previous authors, using simulated images at variable signal-to-noise ratios. To these we add a new test of the error due to a non-uniform background. Finally the tracking of particles in real cell images is demonstrated. The method is made freely available for non-commencial use as a software package with a graphical user-inferface, which can be run within the Matlab programming environment

The Inflationary Perturbation Spectrum

Motivated by the prospect of testing inflation from precision cosmic microwave background observations, we present analytic results for scalar and tensor perturbations in single-field inflation models based on the application of uniform approximations. This technique is systematically improvable, possesses controlled error bounds, and does not rely on assuming the slow-roll parameters to be constant. We provide closed-form expressions for the power spectra and the corresponding scalar and tensor spectral indices.Comment: 4 pages, 1 figur

Robustness of Cosmological Simulations I: Large Scale Structure

The gravitationally-driven evolution of cold dark matter dominates the formation of structure in the Universe over a wide range of length scales. While the longest scales can be treated by perturbation theory, a fully quantitative understanding of nonlinear effects requires the application of large-scale particle simulation methods. Additionally, precision predictions for next-generation observations, such as weak gravitational lensing, can only be obtained from numerical simulations. In this paper, we compare results from several N-body codes using test problems and a diverse set of diagnostics, focusing on a medium resolution regime appropriate for studying many observationally relevant aspects of structure formation. Our conclusions are that -- despite the use of different algorithms and error-control methodologies -- overall, the codes yield consistent results. The agreement over a wide range of scales for the cosmological tests is test-dependent. In the best cases, it is at the 5% level or better, however, for other cases it can be significantly larger than 10%. These include the halo mass function at low masses and the mass power spectrum at small scales. While there exist explanations for most of the discrepancies, our results point to the need for significant improvement in N-body errors and their understanding to match the precision of near-future observations. The simulation results, including halo catalogs, and initial conditions used, are publicly available.Comment: 32 pages, 53 figures, data from the simulations is available at http://t8web.lanl.gov/people/heitmann/arxiv, accepted for publication in ApJS, several minor revisions, reference added, main conclusions unchange

Integration of sexual and reproductive health services in the provision of primary health care in the Arab States: status and a way forward.

Different approaches are used for integration of sexual and reproductive health (SRH) services at the primary health care (PHC) level, aiming at providing comprehensive services leaving no one behind. This paper aims to assess gaps in the delivery of SRH in PHC services, identifying challenges and proposing action towards universal health coverage in Arab countries. The United Nations Population Fund - Arab States Regional Office (UNFPA/ASRO), in partnership with Middle East and North Africa Health Policy Forum (HPF), launched an assessment of integration of SRH into PHC in 11 Arab countries in 2017-2018. Desk reviews were conducted, using published programme reports and national statistics. Data from country reports were compiled to present a regional assessment, challenges and recommendations. SRH services are partially integrated in PHC. Family planning is part of PHC in all countries except Libya, where only counselling is provided. Only Morocco, Tunisia and Oman provide comprehensive HIV services at PHC level. Jordan, Libya and Saudi Arabia rely mainly on referral to other facilities, while most of the integrated family planning or HIV services in Sudan, Morocco and Oman are provided within the same facilities. Action is required at the policy, organisational and operational levels. Prioritisation of services can guide the development of essential packages of SRH care. Developing the skills of the PHC workforce in SRH services and the adoption of the family medicine/general practice model can ensure proper allocation of resources. A presented regional integration framework needs further efforts for addressing the actions entailed

Hyperfine Fields in an Ag/Fe Multilayer Film Investigated with 8Li beta-Detected Nuclear Magnetic Resonance

Low energy $\beta$-detected nuclear magnetic resonance ($\beta$-NMR) was used to investigate the spatial dependence of the hyperfine magnetic fields induced by Fe in the nonmagnetic Ag of an Au(40 \AA)/Ag(200 \AA)/Fe(140 \AA) (001) magnetic multilayer (MML) grown on GaAs. The resonance lineshape in the Ag layer shows dramatic broadening compared to intrinsic Ag. This broadening is attributed to large induced magnetic fields in this layer by the magnetic Fe layer. We find that the induced hyperfine field in the Ag follows a power law decay away from the Ag/Fe interface with power $-1.93(8)$, and a field extrapolated to $0.23(5)$ T at the interface.Comment: 5 pages, 4 figure. To be published in Phys. Rev.

A Faraday Rotation Search for Magnetic Fields in Large Scale Structure

Faraday rotation of radio source polarization provides a measure of the integrated magnetic field along the observational lines of sight. We compare a new, large sample of Faraday rotation measures (RMs) of polarized extragalactic sources with galaxy counts in Hercules and Perseus-Pisces, two nearby superclusters. We find that the average of RMs in these two supercluster areas are larger than in control areas in the same galactic latitude range. This is the first RM detection of magnetic fields that pervade a supercluster volume, in which case the fields are at least partially coherent over several megaparsecs. Even the most conservative interpretation of our observations, according to which Milky Way RM variations mimic the background supercluster galaxy overdensities, puts constraints on the IGM magneto-ionic ``strength'' in these two superclusters. We obtain an approximate typical upper limit on the field strength of about 0.3 microGauss l/(500 kpc), when we combine our RM data with fiducial estimates of electron density from the environments of giant radio galaxies, and of the warm-hot intergalactic medium (WHIM).Comment: 8 pages, 3 figures, 1 table, to appear in the Astrophysical Journa