ABSTRACT The Atacama Cosmology Telescope (ACT) makes high angular resolution measurements of anisotropies in the Cosmic Microwave Background (CMB) at millimeter wavelengths. We describe ACTPol, an ...upgraded receiver for ACT, which uses feedhorn-coupled, polarization-sensitive detector arrays, a 3° field of view, 100 mK cryogenics with continuous cooling, and meta material antireflection coatings. ACTPol comprises three arrays with separate cryogenic optics: two arrays at a central frequency of 148 GHz and one array operating simultaneously at both 97 GHz and 148 GHz. The combined instrument sensitivity, angular resolution, and sky coverage are optimized for measuring angular power spectra, clusters via the thermal Sunyaev-Zel'dovich (SZ) and kinetic SZ signals, and CMB lensing due to large-scale structure. The receiver was commissioned with its first 148 GHz array in 2013, observed with both 148 GHz arrays in 2014, and has recently completed its first full season of operations with the full suite of three arrays. This paper provides an overview of the design and initial performance of the receiver and related systems.
To construct a catalogue of oxygen-rich (M) asymptotic giant branch (AGB) stars in the halo, complementing the catalogues of carbon-rich (C) stars, previous lists of Miras and SRa semi-regulars ...located in the northern hemisphere are merged and cleaned of various defects. After putting aside known C stars, characteristics such as colours and periods indicate that most of the remaining objects are M stars. Distances are obtained through the period-luminosity relation. By considering their position in the sky, stars lying at |Z| > 5 kpc are confirmed to be in majority in the Sgr tidal arms. The M stars are more numerous than C ones. Our distance scale is supported by two cool variables located in the Pal 4 globular cluster. Along the Sgr arms, there is reasonable agreement on distances of our objects with recent RR Lyrae distances. A few stars may be as distant as 150 kpc, with possibly four at the trailing arm apocentre, and two in the A16 sub-structure, angularly close to two C stars. Ninety radial velocities are collected from Gaia and other sources. A catalogue with 417 M pulsating AGB stars is provided. This catalogue contains ∼260 stars in the halo with |Z| > 5 kpc. Their Ks magnitudes range from 8 up to 13. For comparison, the catalogue also provides ∼150 stars in the disc having 5 < Ks < 8.
Pennantia
, which comprises four species distributed in Australasia, was the subject of a monographic taxonomic treatment based on morphological characters in 2002. When this genus has been included ...in molecular phylogenies, it has usually been represented by a single species,
P. corymbosa
J.R.Forst. & G.Forst., or occasionally also by
P. cunninghamii
Miers. This study presents the first dated phylogenetic analysis encompassing all species of the genus
Pennantia
and using chloroplast DNA. The nuclear ribosomal 18S–26S repeat region is also investigated, using a chimeric reference sequence against which reads not mapping to the chloroplast genome were aligned. This mapping of off-target reads proved valuable in exploiting otherwise discarded data, but with rather variable success. The trees based on chloroplast DNA and the nuclear markers are congruent but the relationships among the members of the latter are less strongly supported overall, certainly due to the presence of ambiguous characters in the alignment resulting from low coverage. The dated chloroplast DNA phylogeny suggests that
Pennantia
has diversified within the last 20 My, with the lineages represented by
P. baylisiana
(W.R.B.Oliv.) G.T.S.Baylis,
P. endlicheri
Reissek and
P. corymbosa
diversifying within the last 9 My. The analyses presented here also confirm previous molecular work based on the nuclear internal transcribed spacer region showing that
P. baylisiana
and
P. endlicheri
, which were sometimes considered synonyms, are not sister taxa and therefore support their recognition as distinct species.
Fire is an important ecological disturbance in vegetated ecosystems across the globe, and also has considerable impacts on human infrastructure. Vegetation flammability is a key bottom-up control on ...fire regimes and on the nature of individual fires. Although New Zealand (NZ) historically had low fire frequencies, anthropogenic fires have considerably impacted indigenous vegetation as humans used fire extensively to clear forests. Few studies of vegetation flammability have been undertaken in NZ and only one has compared the flammability of indigenous plants; this was a qualitative assessment derived from expert opinion. We addressed this knowledge gap by measuring the flammability of terminal shoots from a range of trees and shrubs found in NZ. We quantified shoot flammability of 60 indigenous and exotic species, and compared our experimentally derived ranking with expert opinion. The most flammable species was the invasive exotic shrub Gorse (Ulex europaeus), followed by Manna Gum (Eucalyptus viminalis), Kūmarahou (Pomaderris kumeraho), Rimu (Dacrydium cupressinum) and Silver Beech (Lophozonia menziesii). Our experimentally derived ranking was strongly correlated with expert opinion, lending support to both methods. Our results are useful to ecologists seeking to understand how fires have and will influence NZ’s ecosystems, and for fire managers identifying high-risk landscapes, and low flammability species for ‘green firebreaks’.
Terrestrial plants and fire have interacted for at least 420 million years
. Whether recurrent fire drives plants to evolve higher flammability and what the evolutionary pattern of plant flammability ...is remain unclear
. Here, we show that phylogeny, the susceptibility of a habitat to have recurrent fires (that is, fire-proneness) and growth form are important predictors of the shoot flammability of 194 indigenous and introduced vascular plant species (Tracheophyta) from New Zealand. The phylogenetic signal of the flammability components and the variation in flammability among phylogenetic groups (families and higher taxonomic level clades) demonstrate that shoot flammability is phylogenetically conserved. Some closely related species, such as in Dracophyllum (Ericaceae), vary in flammability, indicating that flammability exhibits evolutionary flexibility. Species in fire-prone ecosystems tend to be more flammable than species from non-fire-prone ecosystems, suggesting that fire may have an important role in the evolution of plant flammability. Growth form also influenced flammability-forbs were less flammable than grasses, trees and shrubs; by contrast, grasses had higher biomass consumption by fire than other groups. The results show that shoot flammability of plants is largely correlated with phylogenetic relatedness, and high flammability may result in parallel evolution driven by environmental factors, such as fire regime.
Summary
Some plant traits may be legacies of coevolution with extinct megafauna. One example is the convergent evolution of ‘divaricate’ cage architectures in many New Zealand lineages, interpreted ...as a response to recently extinct flightless avian browsers whose ancestors arrived during the Paleogene period. Although experiments have confirmed that divaricate habit deters extant browsers, its abundance on frosty, droughty sites appears consistent with an earlier interpretation as a response to cold, dry Plio‐Pleistocene climates.
We used 45 protein‐coding sequences from plastid genomes to reconstruct the evolutionary history of the divaricate habit in extant New Zealand lineages. Our dated phylogeny of 215 species included 91% of New Zealand eudicot divaricate species.
We show that 86% of extant divaricate plants diverged from non‐divaricate sisters within the last 5 Ma, implicating Plio‐Pleistocene climates in the proliferation of cage architectures in New Zealand.
Our results, combined with other recent findings, are consistent with the synthetic hypothesis that the browser‐deterrent effect of cage architectures was strongly selected only when Plio‐Pleistocene climatic constraints prevented woody plants from growing quickly out of reach of browsers. This is consistent with the abundance of cage architectures in other regions where plant growth is restricted by aridity or short frost‐free periods.
We compare the absolute gain photometric calibration of the Planck/HFI and Herschel/SPIRE instruments on diffuse emission. The absolute calibration of HFI and SPIRE each relies on planet flux ...measurements and comparison with theoretical far-infrared emission models of planetary atmospheres. We measure the photometric cross calibration between the instruments at two overlapping bands, 545GHz/500 mu m and 857GHz/350 mu m. The HFI maps are bandpass-corrected to match the emission observed by the SPIRE bandpasses. The SPIRE maps are convolved to match the HFI beam and put on a common pixel grid. We measure the cross-calibration relative gain between the instruments using two methods in each field, pixel-to-pixel correlation and angular power spectrum measurements. Of the 5.5% uncertainty for SPIRE, 4% arises from the uncertainty of the effective beam solid angle, which impacts the adopted SPIRE point source to extended source unit conversion factor, highlighting that as a focus for refinement.
Nous parlerons dans cet article de l’expérience « pilote » sur notre intersecteur d’une unité de dépistage précoce de l’autisme et des troubles envahissants du développement (TED), destinée à ...dépister et évaluer des enfants âgés de moins de trois ans, afin de leur proposer le plus rapidement possible des soins adaptés. Dans un premier temps, nous exposerons les différents aspects du travail au sein de cette unité en abordant tout d’abord le travail de réseau, avec en amont, le partenariat avec les différentes structures dont les centres de PMI, et en aval, le partenariat avec les structures de soins qui prendront le relais de la prise en charge de ces enfants. Le travail d’évaluation proprement dit sera ensuite abordé et notre protocole détaillé. Dans un second temps, nous ferons part de réflexions cliniques issues de notre expérience et aborderons la question de l’annonce du diagnostic, de l’alliance et du processus thérapeutique. Ces réflexions seront suivies de vignettes cliniques qui permettront d’illustrer la dimension thérapeutique qui nous semble déjà à l’œuvre lors de cette phase d’évaluation.
In this article we will present our early detection local program of autism and invasive developmental disorders. It is to detect and evaluate children under the age of three, in order to propose proper treatment as quickly as possible. First of all we will present the different aspects of the program working within a network. On one side the collaboration with different structures such as the maternal and infant protection (PMI) and on the other the collaboration with institutions that will specifically take care of these children. The proper evaluation will be then explained and our methods will be further detailed. Secondly, we will share our clinical studies stemmed from our experience and will then consider diagnosis announcement, alliance and therapeutic process. This will then be followed by case studies that will highlight the therapeutic dimension, which already seems to exist in this evaluation phase.
The DIstributed Sensing for COrium Monitoring and Safety (DISCOMS) project considers the use of optical fiber sensing cables embedded into the concrete floor under the reactor vessel for remote ...monitoring of a severe nuclear accident. This article focuses on the selection and testing of single-mode optical fibers with limited radiation-induced attenuation (RIA). To simulate the normal operation period of the reactor, followed by a severe accident, several gamma and mixed (neutron-gamma) irradiations were performed, thanks to the Atomic Energy Commission (CEA) Saclay facilities, POSÉÏDON irradiator and ISIS reactor, up to a gamma cumulative dose of about 2 MGy and fast neutrons fluence (<inline-formula> <tex-math notation="LaTeX">{E} \,\, >1 </tex-math></inline-formula> MeV) of <inline-formula> <tex-math notation="LaTeX">6\times 10^{15} </tex-math></inline-formula> n/cm 2 . In comparison with the first gamma test on standalone fibers, a significant increase of the RIA at 1550 nm appeared during the second test on fibers encapsulated in sensing cables. Molecular hydrogen generated by the cable compound radiolysis induced an increase of the hydroxyl (OH) attenuation broad spectral peak centered at 1380 nm. The radiation-induced OH growth mechanism is confirmed by the comparison of the extended absorption spectral responses of the standalone and encapsulated fibers. A third gamma irradiation run permitted to measure the radiolytic hydrogen production yield of some compounds of a dedicated temperature cable sample. The efficiency of a carbon-coating layer over the silica cladding, acting as a barrier against hydrogen diffusion into the optical fiber core, was successfully tested under gamma irradiation as well as in a final test under neutron irradiation.
As part of our ongoing study of the evolved giants in the galactic halo, we consider the sample of 1286 long-period variables (LPVs) in the southern hemisphere provided by the Catalina Sky Survey ...experiment. These LPVs have periods P > 80 days and amplitudes >0.2 mag. First, by using the Hamburg/ESO spectral survey, we aim to determine the spectral type as either M-type or C-type for objects located in the imprint of this survey, |b| > 30°. Of 135 LPVs obeying this selection, we classified 93, and found only two new carbon stars. Secondly, we consider faint LPVs. We discovered that many lie at ~1 arcmin from a bright Mira catalogued in the General Catalog of Variable Stars (GCVS) with identical period. We study these suspicious cases in detail, and conclude that for as many as 56 faint Catalina LPVs, their variability is due to contamination by light from the bright, neighboring GCVS Mira: an instrumental artefact. We conclude that when dealing with distant, faint Miras in the Catalina catalog, researchers should pay attention to the polluting effects of neighbouring bright and variable objects.
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