Drifting sub-pulses in two newly discovered pulsars

We have detected the rare phenomenon of stable, drifting sub-pulse behaviour in two pulsars discovered in the recent Swinburne intermediate latitude pulsar survey. The pulsars; PSR J1231-47 and PSR J1919+0134, have approximate periods (P) of 1.873 and 1.6039 seconds respectively. Both pulsars have multi-component profiles, and distinct drifting is observed across them. We have identified a single drift mode in both pulsars: the drift rate for PSR J1231-47 being 5.4(1) ms P^{-1} and 5.8(2) ms P^{-1} for PSR 1919+0134. The drifting is linear across the profile with no departure from linearity at the edges within the sensitivity of our observations.Comment: 4 pages, 2 figures. Accepted by Monthly Notices of the Royal Astronomical Societ

Radiologists' Attitudes and Use of Mammography Audit Reports

The U.S. Mammography Quality Standards Act (MQSA) mandates medical audits to track breast cancer outcomes data associated with interpretive performance. The objectives of our study were to assess the content and style of audits and examine use of, attitudes toward, and perceptions of the value that radiologists' have regarding mandated medical audits

Growth Based Morphogenesis of Vertebrate Limb Bud

Many genes and their regulatory relationships are involved in developmental phenomena. However, by chemical information alone, we cannot fully understand changing organ morphologies through tissue growth because deformation and growth of the organ are essentially mechanical processes. Here, we develop a mathematical model to describe the change of organ morphologies through cell proliferation. Our basic idea is that the proper specification of localized volume source (e.g., cell proliferation) is able to guide organ morphogenesis, and that the specification is given by chemical gradients. We call this idea “growth-based morphogenesis.” We find that this morphogenetic mechanism works if the tissue is elastic for small deformation and plastic for large deformation. To illustrate our concept, we study the development of vertebrate limb buds, in which a limb bud protrudes from a flat lateral plate and extends distally in a self-organized manner. We show how the proportion of limb bud shape depends on different parameters and also show the conditions needed for normal morphogenesis, which can explain abnormal morphology of some mutants. We believe that the ideas shown in the present paper are useful for the morphogenesis of other organs

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Kurzer, gestörter und unregelmäßiger Schlaf: Die schädlichen Auswirkungen auf den menschlichen Stoffwechsel.

In unserer modernen 24-Stunden-Gesellschaft zeigt sich ein zunehmender Trend zu verkürztem und unregelmäßigem Schlaf. Parallel hierzu nimmt die Prävalenz des metabolischen Syndroms mit seinen Kernkomponenten Adipositas und Typ-2-Diabetes mellitus stetig zu, wie eine Vielzahl epidemiologischer Arbeiten belegen. Experimentelle kurzzeitige Interventionsstudien weisen auf einen kausalen Zusammenhang zwischen Schlafdauer und -qualität und Energiemetabolismus hin und haben zugrundeliegende Mechanismen identifiziert. Insbesondere Veränderungen in der neuroendokrinen Regulation des Glukosestoffwechsels, der zirkadianen Rhythmik sowie von Appetit und Essverhalten scheinen die negativen Auswirkungen von unzureichendem Schlaf auf den Energiehaushalt zu vermitteln. Auch wenn langfristige Interventionsstudien bislang fehlen, kann davon ausgegangen werden, dass eine Verbesserung der Schlafhygiene einen attraktiven Ansatz in der Prävention und Therapie metabolischer Erkrankungen darstellt

Assessment and field-scale mapping of soil quality properties of a saline-sodic soil

Salt-affected soils could produce useful forages when irrigated with saline drainage water. To assess the productive potential and sustainability of using drainage water for forage production, a saline-sodic site (32.4 ha) in California's San Joaquin Valley was characterized for soil quality. The objectives were (1) to spatially characterize initial soil physicochemical properties relevant to maintaining soil quality on an arid zone soil and (2) to characterize soil quality relationships and spatial variability.An initial mobile electromagnetic (EM) induction survey was conducted in 1999, with bulk soil electrical conductivity (ECa) readings taken at 384 geo-referenced locations, followed by an intensive mobile fixed-array survey with a total of 7288 geo-referenced ECa readings. Using the EM data and a spatial statistics program (ESAP v2.0), 40 sites were selected that reflected the spatial heterogeneity of the ECa measurements for the study area. At these sites, soil-core samples were taken at 0.3-m intervals to a depth of 1.2 m. Duplicate samples were taken at eight sites to study the local-scale variability of soil properties. Soil-core samples were analyzed for a variety of physical and chemical properties related to the soil quality of arid zone soils.Soils were found to be highly spatially heterogeneous. For composite soil-core samples taken to a depth of 1.2 m, ECe (electrical conductivity of the saturation extract) varied from 12.8 to 36.6 dS m-1, SAR from 28.8 to 88.8, and clay content from 2.5% to 48.3%. B and Mo concentrations varied from 11.5 to 32.2 mg l-1 and 476.8 to 1959.6 g l-1, respectively. CaCO3, NO3- in the saturation extract, exchangeable Ca2 , Se, and As consistently had the highest coefficients of variation (CV) while pHe, b, and Ca2 in the saturation extract consistently had the lowest CVs at all depths. A one-way analysis of variance (ANOVA) was used to spatially partition the local- and global-scale variability. Local-scale variability was greatest for pHe. Laboratory measurements of saturated hydraulic conductivity (Ks) were very low (0.0000846-0.0456 cm h-1), whereas field measurements were considerably higher (0.49-1.79 cm h-1). Based on the Cl- data, the leaching fraction (LF) for the entire study area was estimated to be 17%.Soil quality was reflected in yield and chemical analysis of forage. Forage Mo contents determined from newly established Bermuda grass varied from 1 to 5 mg kg-1 on a dry matter basis, and Cu/Mo ratios averaged 3.3, while forage yield in the establishment year declined with ECe, and failed to grow above ECe levels of approximately 22 dS m-1. The initial soil quality assessment of the research site indicated that the sustainability of drainage water reuse at this location would depend upon maintaining a sufficient LF with careful consideration and management of salinity, boron, molybdenum, and sodium levels

Assessment and field-scale mapping of soil quality properties of a saline-sodic soil

Salt-affected soils could produce useful forages when irrigated with saline drainage water. To assess the productive potential and sustainability of using drainage water for forage production, a saline-sodic site (32.4 ha) in California's San Joaquin Valley was characterized for soil quality. The objectives were (1) to spatially characterize initial soil physicochemical properties relevant to maintaining soil quality on an arid zone soil and (2) to characterize soil quality relationships and spatial variability.An initial mobile electromagnetic (EM) induction survey was conducted in 1999, with bulk soil electrical conductivity (ECa) readings taken at 384 geo-referenced locations, followed by an intensive mobile fixed-array survey with a total of 7288 geo-referenced ECa readings. Using the EM data and a spatial statistics program (ESAP v2.0), 40 sites were selected that reflected the spatial heterogeneity of the ECa measurements for the study area. At these sites, soil-core samples were taken at 0.3-m intervals to a depth of 1.2 m. Duplicate samples were taken at eight sites to study the local-scale variability of soil properties. Soil-core samples were analyzed for a variety of physical and chemical properties related to the soil quality of arid zone soils.Soils were found to be highly spatially heterogeneous. For composite soil-core samples taken to a depth of 1.2 m, ECe (electrical conductivity of the saturation extract) varied from 12.8 to 36.6 dS m-1, SAR from 28.8 to 88.8, and clay content from 2.5% to 48.3%. B and Mo concentrations varied from 11.5 to 32.2 mg l-1 and 476.8 to 1959.6 g l-1, respectively. CaCO3, NO3- in the saturation extract, exchangeable Ca2 , Se, and As consistently had the highest coefficients of variation (CV) while pHe, b, and Ca2 in the saturation extract consistently had the lowest CVs at all depths. A one-way analysis of variance (ANOVA) was used to spatially partition the local- and global-scale variability. Local-scale variability was greatest for pHe. Laboratory measurements of saturated hydraulic conductivity (Ks) were very low (0.0000846-0.0456 cm h-1), whereas field measurements were considerably higher (0.49-1.79 cm h-1). Based on the Cl- data, the leaching fraction (LF) for the entire study area was estimated to be 17%.Soil quality was reflected in yield and chemical analysis of forage. Forage Mo contents determined from newly established Bermuda grass varied from 1 to 5 mg kg-1 on a dry matter basis, and Cu/Mo ratios averaged 3.3, while forage yield in the establishment year declined with ECe, and failed to grow above ECe levels of approximately 22 dS m-1. The initial soil quality assessment of the research site indicated that the sustainability of drainage water reuse at this location would depend upon maintaining a sufficient LF with careful consideration and management of salinity, boron, molybdenum, and sodium levels

Will You Still Need Me: When I’m 64?

age, productivity, matched worker-firm data, J14, J24, J31,