Neutron depolarization studies of Pd-Ni-Fe-P alloy

Bulk metallic glasses based on the quaternary alloy Pd-Ni-Fe-P exhibit interesting phase behavior depending on temperature and applied magnetic field. Previous work has suggested that a range of magnetic phases including paramagnetic, superparamagnetic, ferromagnetic and spin glass can be observed in this system. We have applied one dimensional neutron depolarization to explore the correlation of magnetic moments in Pd40Ni22.5Fe17.5P20 alloy as a function of temperature and applied magnetic field. The results provided evidence for correlation lengths of ~ 200 Å. The nature of the correlations and the formation mechanism of the induced ferromagnetic phase are discusse

The Primordial Inflation Explorer (PIXIE): A Nulling Polarimeter for Cosmic Microwave Background Observations

The Primordial Inflation Explorer (PIXIE) is an Explorer-class mission to measure the gravity-wave signature of primordial inflation through its distinctive imprint on the linear polarization of the cosmic microwave background. The instrument consists of a polarizing Michelson interferometer configured as a nulling polarimeter to measure the difference spectrum between orthogonal linear polarizations from two co-aligned beams. Either input can view the sky or a temperature-controlled absolute reference blackbody calibrator. PIXIE will map the absolute intensity and linear polarization (Stokes I, Q, and U parameters) over the full sky in 400 spectral channels spanning 2.5 decades in frequency from 30 GHz to 6 THz (1 cm to 50 um wavelength). Multi-moded optics provide background-limited sensitivity using only 4 detectors, while the highly symmetric design and multiple signal modulations provide robust rejection of potential systematic errors. The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r < 10^{-3} at 5 standard deviations. The rich PIXIE data set will also constrain physical processes ranging from Big Bang cosmology to the nature of the first stars to physical conditions within the interstellar medium of the Galaxy.Comment: 37 pages including 17 figures. Submitted to the Journal of Cosmology and Astroparticle Physic

Behaviour and Climate Change: Consumer Perceptions of Responsibility

This paper explores the under-researched notion of consumer responsibility, a potentially significant influence on consumer behaviour that marketers and policymakers may be able to harness as they attempt to respond to environmental challenges such as climate change. The paper uses data derived from a commercially motivated survey (n = 1513) to explore domestic consumption behaviours most closely associated with the issue of disruptive climate change. A measure of 'General Environmental Responsiveness' (GER) is used to test: (1) the effects of consumers both taking responsibility for their actions and placing responsibility on others for the consequences of their consumption behaviour; and (2) whether sociodemographic variables can aid the targeting of consumers by the level and type of responsibility and pro-environmental behavioural intentions expressed. The study's findings demonstrate clear, if not strong, relationships between consumer conceptions of responsibilities for causing and tackling climate change and environment-related consumer behaviour. The study's implications both challenge accepted wisdom about environment-related consumer behaviour and suggest avenues for future research

Possible origins of macroscopic left-right asymmetry in organisms

I consider the microscopic mechanisms by which a particular left-right (L/R) asymmetry is generated at the organism level from the microscopic handedness of cytoskeletal molecules. In light of a fundamental symmetry principle, the typical pattern-formation mechanisms of diffusion plus regulation cannot implement the "right-hand rule"; at the microscopic level, the cell's cytoskeleton of chiral filaments seems always to be involved, usually in collective states driven by polymerization forces or molecular motors. It seems particularly easy for handedness to emerge in a shear or rotation in the background of an effectively two-dimensional system, such as the cell membrane or a layer of cells, as this requires no pre-existing axis apart from the layer normal. I detail a scenario involving actin/myosin layers in snails and in C. elegans, and also one about the microtubule layer in plant cells. I also survey the other examples that I am aware of, such as the emergence of handedness such as the emergence of handedness in neurons, in eukaryote cell motility, and in non-flagellated bacteria.Comment: 42 pages, 6 figures, resubmitted to J. Stat. Phys. special issue. Major rewrite, rearranged sections/subsections, new Fig 3 + 6, new physics in Sec 2.4 and 3.4.1, added Sec 5 and subsections of Sec

Labor neuraxial analgesia and breastfeeding: An updated systematic review

Introduction: There have been numerous reports studying the effect of neuraxial analgesia on breastfeeding success, but the results are inconsistent. Methods: We performed a literature search in various databases for studies comparing neuraxial analgesia to non-neuraxial or no analgesia. Outcomes were the percentage of women breastfeeding fully or mixed with formula. Where possible, nulliparous parturients were analyzed separately. We conducted an analysis excluding studies of serious and critical risk of bias. Odds ratios and 95% confidence intervals were calculated. Results: We included 15 studies (13 observational studies, 1 secondary analysis of a randomized controlled trial, 1 case-control study) with 16,112 participants. Overall, there were 6 studies that found no difference between groups, 6 studies that showed a significantly lower incidence of breastfeeding in the neuraxial group and 3 studies finding mixed results (at some time-points statistically significant and at some time-point statistically non-significant results). In nulliparous only studies, 2 found no difference between study groups, 1 found a lower breastfeeding rate in the neuraxial group and 3 studies showed mixed results. Excluding studies with a serious and critical risk of bias, 1 study found no difference between study groups, 3 studies found a decrease of breastfeeding rates in the neuraxial group, and 1 study showed mixed results. Discussion: In our review we found a high disparity in results. One reason is probably the high potential of confounding (immediate skin to skin placement, maternity leave etc.). Education programs and breastfeeding support are likely more important in determining long term breastfeeding success

On the induction of different kinds of first-order fuzzy rules

International audienceThe paper describes a method for inducing first-order rules with fuzzy predicates from a database. First, the paper makes a distinction between fuzzy rules allowing for some tolerance with respect to the interpretative scope of the predicates, and fuzzy rules airning at expressing a set of ordinary rules in a global way. Moreover the paper only considers the induction of Horn-like implicative-based fuzzy rules. Specific confidence degrees are associated with each kind of fuzzy rules in the inductive process. This technique is illustrated on an experimental application. The interest of learning varioiis types of fuzzy first-order logic expressions is emphasized