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We describe 14 yr of public data from the Parkes Pulsar Timing Array (PPTA), an ongoing project that is producing precise measurements of pulse times of arrival from 26 millisecond pulsars using the 64-m Parkes radio telescope with a cadence of approximately 3 weeks in three observing bands. A comprehensive description of the pulsar observing systems employed at the telescope since 2004 is provided, including the calibration methodology and an analysis of the stability of system components. We attempt to provide full accounting of the reduction from the raw measured Stokes parameters to pulse times of arrival to aid third parties in reproducing our results. This conversion is encapsulated in a processing pipeline designed to track provenance. Our data products include pulse times of arrival for each of the pulsars along with an initial set of pulsar parameters and noise models. The calibrated pulse profiles and timing template profiles are also available. These data represent almost 21 000 h of recorded data spanning over 14 yr. After accounting for processes that induce time-correlated noise, 22 of the pulsars have weighted root-mean-square timing residuals of
in at least one radio band. The data should allow end users to quickly undertake their own gravitational wave analyses, for example, without having to understand the intricacies of pulsar polarisation calibration or attain a mastery of radio frequency interference mitigation as is required when analysing raw data files.
Even gods are not always above bureaucracy. Societies very different from each other have entertained the idea that the heavens might be arranged much like an earthly bureaucracy, or that mythological beings might exercise their power in a way that makes them resembles bureaucrats. The best-known case is the Chinese “celestial bureaucracy,” but the idea is also found in (to take nearly random examples) Ancient Near Eastern cosmology, the Hebrew Bible, Late Antiquity, and modern popular culture. The primary sources discussed in this essay pertain to an area of history where bureaucracy was historically underdeveloped, namely medieval Scandinavia. Beginning with the Glavendrup runestone from the 900s, I examine a way of thinking about divine power that seems blissfully bureaucracy-free. Moving forwards in time to Adam of Bremen’s description of the temple at Uppsala (1040s–1070s), I find traces of a tentative, half-formed bureaucracy in the fading embers of Scandinavian paganism. In the 1220s, well into the Christian era, I find Snorri Sturluson concocting a version of Old Norse myth which proposes a novel resolution between the non-bureaucratic origins of his mythological corpus and the burgeoning bureacratization of High Medieval Norway. Although my focus is on medieval Scandinavia, transhistorical comparisons are frequently drawn with mythological bureaucrats from other times and places. In closing, I synthesise this comparative material with historical and anthropological theories of the relationship between bureaucracy and the divine.
Timing of weed emergence and seed persistence in the soil influence the ability to implement timely and effective control practices. Emergence patterns and seed persistence of kochia populations were monitored in 2010 and 2011 at sites in Kansas, Colorado, Wyoming, Nebraska, and South Dakota. Weekly observations of emergence were initiated in March and continued until no new emergence occurred. Seed was harvested from each site, placed into 100-seed mesh packets, and buried at depths of 0, 2.5, and 10 cm in fall of 2010 and 2011. Packets were exhumed at 6-mo intervals over 2 yr. Viability of exhumed seeds was evaluated. Nonlinear mixed-effects Weibull models were fit to cumulative emergence (%) across growing degree days (GDD) and to viable seed (%) across burial time to describe their fixed and random effects across site-years. Final emergence densities varied among site-years and ranged from as few as 4 to almost 380,000 seedlings m−2. Across 11 site-years in Kansas, cumulative GDD needed for 10% emergence were 168, while across 6 site-years in Wyoming and Nebraska, only 90 GDD were needed; on the calendar, this date shifted from early to late March. The majority (>95%) of kochia seed did not persist for more than 2 yr. Remaining seed viability was generally >80% when seeds were exhumed within 6 mo after burial in March, and declined to <5% by October of the first year after burial. Burial did not appear to increase or decrease seed viability over time but placed seed in a position from which seedling emergence would not be possible. High seedling emergence that occurs very early in the spring emphasizes the need for fall or early spring PRE weed control such as tillage, herbicides, and cover crops, while continued emergence into midsummer emphasizes the need for extended periods of kochia management.
We studied neuroinflammation in individuals with late-life, depression, as a
risk factor for dementia, using [11C]PK11195 positron emission
tomography (PET). Five older participants with major depression and 13
controls underwent PET and multimodal 3T magnetic resonance imaging (MRI),
with blood taken to measure C-reactive protein (CRP). We found significantly
higher CRP levels in those with late-life depression and raised
[11C]PK11195 binding compared with controls in brain regions
associated with depression, including subgenual anterior cingulate cortex,
and significant hippocampal subfield atrophy in cornu ammonis 1 and
subiculum. Our findings suggest neuroinflammation requires further
investigation in late-life depression, both as a possible aetiological
factor and a potential therapeutic target.
Retrograde transport is a process in which proteins are trafficked from the plasma membrane and endosomes to biosynthetic and secretory organelles, namely the Golgi apparatus and endoplasmic reticulum (ER). A number of plant and bacterial toxins, including cholera toxin and ricin toxin, exploit retrograde transport to gain entry into host cells, although the specifics of this process have remained difficult to probe by laser scanning confocal microscopy (LSCM). Here we demonstrate the use of super-resolution and live-cell imaging [stimulated emission depletion (STED)] to visualize exogenously applied ricin toxin within the ER. The improved resolution obtained by STED, as compared with LSCM (0.09 versus 0.19 μm), provides a more accurate determination of the amount of ricin that had trafficked to the ER.
This work provides new insights into human responses to and perceptions of sea-level rise at a time when the landscapes of north-west Europe were radically changing. These issues are investigated through a case study focused on the Channel Islands. We report on the excavation of two sites, Canal du Squez in Jersey and Lihou (GU582) in Guernsey, and the study of museum collections across the Channel Islands. We argue that people were drawn to this area as a result of the dynamic environmental processes occurring and the opportunities these created. The evidence suggests that the area was a particular focus during the Middle Mesolithic, when Guernsey and Alderney were already islands and while Jersey was a peninsula of northern France. Insularisation does not appear to have created a barrier to occupation during either the Middle or Final Mesolithic, indicating the appearance of lifeways increasingly focused on maritime voyaging and marine resources from the second half of the 9th millennium BC onwards.
Research was conducted from 2011 to 2014 to determine weed population
dynamics and frequency of glyphosate-resistant (GR) Palmer amaranth with
herbicide programs consisting of glyphosate, dicamba, and residual
herbicides in dicamba-tolerant cotton. Five treatments were maintained in
the same plots over the duration of the experiment: three sequential POST
applications of glyphosate with or without pendimethalin plus diuron PRE;
three sequential POST applications of glyphosate plus dicamba with and
without the PRE herbicides; and a POST application of glyphosate plus
dicamba plus acetochlor followed by one or two POST applications of
glyphosate plus dicamba without PRE herbicides. Additional treatments
included alternating years with three sequential POST applications of
glyphosate only and glyphosate plus dicamba POST with and without PRE
herbicides. The greatest population of Palmer amaranth was observed when
glyphosate was the only POST herbicide throughout the experiment. Although
diuron plus pendimethalin PRE in a program with only glyphosate POST
improved control during the first 2 yr, these herbicides were ineffective by
the final 2 yr on the basis of weed counts from soil cores. The lowest
population of Palmer amaranth was observed when glyphosate plus dicamba were
applied regardless of PRE herbicides or inclusion of acetochlor POST.
Frequency of GR Palmer amaranth was 8% or less when the experiment was
initiated. Frequency of GR Palmer amaranth varied by herbicide program
during 2012 but was similar among all herbicide programs in 2013 and 2014.
Similar frequency of GR Palmer amaranth across all treatments at the end of
the experiment most likely resulted from pollen movement from Palmer
amaranth treated with glyphosate only to any surviving female plants
regardless of PRE or POST treatment. These data suggest that GR Palmer
amaranth can be controlled by dicamba and that dicamba is an effective
alternative mode of action to glyphosate in fields where GR Palmer amaranth
It is widely accepted that between the beginning of the Early Neolithic period and the end of the Early Bronze Age different regions of Britain were connected to one another by sea, but little is known about the nature of maritime contacts before plank-built boats developed during the 2nd millennium bc. This paper considers a series of coastal sites, some of which were first settled from Mesolithic times. From the early 4th millennium they were also associated with artefact production and the use of imported objects and raw materials. Their distribution focuses on the region of isostatic uplift in northern Britain where the ancient shoreline still survives. It is considered in relation to a new model of coastal change which suggests that these locations were characterised by natural havens sheltered behind islands or bars. The sites can be compared with the ‘landing places’ and ‘beach markets’ discussed by historical archaeologists in recent years.
Where better to begin a consideration of fear and the modern politics of representation than with the self-identified ‘shock’ Charles Baudelaire experienced sometime between ‘1846 and ‘47’ when he first discovered ‘a few fragments by Edgar Poe’? (1986: 148). To underscore the importance of his discovery, Baudelaire's letter divides his reaction to Poe's work into two categories. On an aesthetic level, the jarring power of Poe's fragmentary narrative exposition enabled a new mode of representation to reveal shocking moments of emotional uncertainty. The ‘poems and short stories’ Baudelaire happened upon in Paris were organised ‘in a vague, confused, disorderly way’, enacting a metaphorics of correspondences ‘that Poe had been able to bring together to perfection’ to expose a defensive struggle for self-expression and emotional coherence in the face of a fleeting and contingent view of everyday modern life (ibid.). But there is a second and unapologetically political response worthy of discussion here. It was Poe's dark vision of a democratic and progressive history that galvanised Baudelaire's commitments to develop one of the most unsettling features in his poetry. A mob fear haunts Les Fleurs du mal. And although my critical examination will resist the reductive assertion that Baudelaire's complicated politics were categorically anti-democratic, his fear of the court of public opinion as the immanent ordering force in modern life does offer a remarkably lucid, at times shockingly contentious, point of re-entry into his work. The issue can be rephrased thus: it was precisely in Poe's terrifying portrayals of the escalating conflict between the will of the supposedly free individual and the mass public that resonated with Baudelaire's concerns about the widening gap between individual liberty and democratic rule. A fear of the unchecked power of the multitude was therefore difficult for Baudelaire to endure but more intolerable to surrender.
Baudelaire recognised non-rational impulses were guiding the political motivations of an emerging mass public.
Objectives: The headroom approach to medical device development relies on the estimation of a value-based price ceiling at different stages of the development cycle. Such price-ceilings delineate the commercial opportunities for new products in many healthcare systems. We apply a simple model to obtain critical business information as the product proceeds along a development pathway, and indicate some future directions for the development of the approach.
Methods: Health economic modelling in the supply-side development cycle for new products.
Results: The headroom can be used: initially as a ‘reality check’ on the viability of the device in the healthcare market; to support product development decisions using a real options approach; and to contribute to a pricing policy which respects uncertainties in the reimbursement outlook.
Conclusions: The headroom provides a unifying thread for business decisions along the development cycle for a new product. Over the course of the cycle attitudes to uncertainty will evolve, based on the timing and manner in which new information accrues. Within this framework the developmental value of new information can justify the costs of clinical trials and other evidence-gathering activities. Headroom can function as a simple shared tool to parties in commercial negotiations around individual products or groups of products. The development of similar approaches in other contexts holds promise for more rational planning of service provision.
Federalism is a core principle of American government; yet, how much attention is given to federalism beyond introductory courses? A 1969 study described American federalism as the “dark continent” of political science teaching. Based on surveys of chairs of US departments of political science and members of the APSA’s section on federalism and intergovernmental relations in 2013, the authors found that these course offerings have increased markedly since 1969, that the courses cover a range of topics, and that many department chairs are interested in offering these courses in the future. However, the teaching of comparative federalism lags far behind American federalism. Thus, comparative federalism remains a “dark continent” of federalism teaching.
We use a WISE-2MASS-Pan-STARRS1 galaxy catalog to search for a supervoid in the direction of the Cosmic Microwave Background Cold Spot. We obtain photometric redshifts using our multicolor data set to create a tomographic map of the galaxy distribution. The radial density profile centred on the Cold Spot shows a large low density region, extending over 10's of degrees. Motivated by previous Cosmic Microwave Background results, we test for underdensities within two angular radii, 5°, and 15°. Our data, combined with an earlier measurement by Granett et al. 2010, are consistent with a large Rvoid=(192 ± 15)h−1 Mpc (2σ) supervoid with δ ≃ −0.13 ± 0.03 centered at z=0.22 ± 0.01. Such a supervoid, constituting a ∼3.5 σ fluctuation in the ΛCDM model, is a plausible cause for the Cold Spot.
The WAIS (West Antarctic Ice Sheet) Divide deep ice core was recently completed to a total depth of 3405 m, ending 50 m above the bed. Investigation of the visual stratigraphy and grain characteristics indicates that the ice column at the drilling location is undisturbed by any large-scale overturning or discontinuity. The climate record developed from this core is therefore likely to be continuous and robust. Measured grain-growth rates, recrystallization characteristics, and grain-size response at climate transitions fit within current understanding. Significant impurity control on grain size is indicated from correlation analysis between impurity loading and grain size. Bubble-number densities and bubble sizes and shapes are presented through the full extent of the bubbly ice. Where bubble elongation is observed, the direction of elongation is preferentially parallel to the trace of the basal (0001) plane. Preferred crystallographic orientation of grains is present in the shallowest samples measured, and increases with depth, progressing to a vertical-girdle pattern that tightens to a vertical single-maximum fabric. This single-maximum fabric switches into multiple maxima as the grain size increases rapidly in the deepest, warmest ice. A strong dependence of the fabric on the impurity-mediated grain size is apparent in the deepest samples.
Peyer's patches, macroscopic aggregates of lymphoid follicles present throughout the small intestines of humans and other mammals, are considered the gateway through which luminal dietary antigens and microbes are sampled by the mucosal immune system. The cellular make-up of Peyer's patch lymphoid follicles is not only complex, but highly dynamic, as there are at least four major cell types that are known to migrate in response to antigenic stimulation. In an effort to capture the complexity and dynamic nature of this specialized tissue, here we report the three-dimensional (3D) reconstruction of immunofluorescent-labeled mouse Peyer's patch cryosections. The technology that enabled the stacking and linear blending of serial cryosections was a novel macro for Fiji, the open source image-processing package based on ImageJ. By simultaneously labeling cryosections for surface markers CD45R, CD3, and CD11c, we provide a 3D image as well as quantitative measures of B-cell, T-cell, and dendritic cell populations at steady state and following exposure to the mucosal adjuvant cholera toxin.
As part of an ongoing effort to increase image reproducibility and fidelity in addition to improving cross-instrument consistency, we have proposed using four separate instrument quality tests to augment the ones we have previously reported. These four tests assessed the following areas: (1) objective lens quality, (2) resolution, (3) accuracy of the wavelength information from spectral detectors, and (4) the accuracy and quality of spectral separation algorithms. Data were received from 55 laboratories located in 18 countries. The largest source of errors across all tests was user error which could be subdivided between failure to follow provided protocols and improper use of the microscope. This truly emphasizes the importance of proper rigorous training and diligence in performing confocal microscopy experiments and equipment evaluations. It should be noted that there was no discernible difference in quality between confocal microscope manufactures. These tests, as well as others previously reported, will help assess the quality of confocal microscopy equipment and will provide a means to track equipment performance over time. From 62 to 97% of the data sets sent in passed the various tests demonstrating the usefulness and appropriateness of these tests as part of a larger performance testing regiment.
An Ensemble Pulsar Time Scale (EPT) is derived based on the Pulsar Timing Array. It is interesting to compare the EPT with the TT terrestrial time scale, and get many new realization on the pulsar time scale and the algorithm. Some future interesting applications of the EPT are described and discussed.
Background: Delirium among long-term care (LTC) residents is frequent and is associated with increased morbidity and mortality. Identification of clinical changes during the prodromal phase of delirium could lead to prevention of a full-blown episode and perhaps limit the deleterious consequences of this syndrome. The aim of the present study was to identify clinical changes observable in the 2-week period prior to the onset of full-blown delirium.
Methods: Long-term care (LTC) residents aged 65 years and over, with or without dementia were eligible for this nested case-control study. Delirium was assessed weekly over a 6-month period using the Confusion Assessment Method. Cases with incident delirium were matched by time since enrolment to one or more controls without delirium.
Results: When compared to the controls, LTC residents who developed delirium (cases = 85) were more likely to have new-onset perceptual disturbances (OR = 4.75; 95% CI 1.65–13.66) and disorganized thinking (OR = 3.09; 95% CI 1.33–7.19) and a worsening of the Mini-Mental State Examination (MMSE) item measuring registration (OR = 2.59; 95% CI 1.24–5.41) during the preceding 2 weeks. However, the frequency of these changes was low. Residents with at least 3 clinical changes were more likely to develop delirium than those without any clinical change (OR = 2.52; 95% CI 1.08–5.87).
Conclusions: This study provides evidence of clinical changes during the prodromal phase of delirium among LTC residents. More studies are needed to further explore the role and relevance of these clinical changes as warning signs of imminent delirium.
The days of being able to ascertain instrument performance by simply peering through the eye pieces at a specimen are gone. However, users and granting agencies need to be confident that data collected on these instruments is uniform and quantifiable both over time and between instruments. Ideally, a LASER should not fluctuate, illumination should be completely uniform, and colors should be perfectly aligned. To check the current performance of imaging equipment, we conducted a worldwide research study utilizing three image-based tests: long-/short-term illumination stability, co-registration of signals across various wavelengths, and field illumination uniformity. To differentiate between “acceptable” and “unacceptable” performance, the deviation in illumination power could not exceed 10% (long term) or 3% (short term), the difference in the center-of-mass of imaged multicolored beads could not exceed >1 pixel between different wavelengths, and field illumination values could not exceed 10% (horizontal) or 20% (diagonal) deviation. This study established the current state of microscope performance through simple, efficient, and robust tests, while defining relative standards to assist cores in maintaining their instruments in optimal operating conditions. We developed cross-platform performance standards that will improve the validity of quantitative measurements made using various light microscopes.