125 research outputs found
BODY TEMPERATURE OF CAPTIVE MOOSE INFESTED WITH WINTER TICKS
Eighteen captive moose calves (Alces alces) were divided into 3 groups that represented 3 levels of winter tick (Dermacentor albipictus) infestation (0, 21,000, and 42,000 ticks). A total of 321 body temperatures (Tb) were taken on 19 occasions between late November and mid-April. The mean Tb of individuals was 38.2 ± 0.4 °C, ranging from 38.0–38.3 °C, and was not different among the control and infested groups (P = 0.816), but varied temporally (P < 0.001) with a significant interaction effect between treatment and time (P = 0.041); these temporal differences are unexplained. The Tbs measured in this study are some of the lowest reported for moose and presumably represent the resting Tb of free-ranging moose, more so than those measured after pursuit, restraint, and/or immobilization during capture. This was not a definitive test of the effects of tick infestation on wild moose because the captive moose consumed a high quality diet throughout winter and surprisingly low numbers of ticks remained on the animals in mid-April
SHIVERING BY CAPTIVE MOOSE INFESTED WITH WINTER TICKS
Occurence and rate of shivering were measured to assess thermoregulatory responses of captive moose (Alces alces) infested with winter ticks (Dermacentor albipictus). Shivering was observed on 47 occasions in 5 of 8 infested moose calves from October to April; in contrast, 4 moose calves not infested with winter ticks did not shiver under identical weather conditions. Only 5 shivering bouts occurred from October to March, all on a single day. The other 42 shivering bouts occurred in April with bouts lasting 1–103 min. During the April bouts, ambient temperature was 1– 4 °C (42 of 42), maximum wind speed was ≤12 km/h (38 of 42), and it was raining (30 of 42). Shivering was associated with 23–44% hair loss in April, but not during cold weather in mid-winter despite 5–10% hair loss in March. Maintaining stable core body temperature during late winter-early spring could compromise the energetic balance of wild free-ranging moose with extensive hair loss and abundant ticks, in conditions equivalent to or worse than measured in this study
(2-Carbamoylethyl-κ2 C 1,O)triiodidotin(IV)
Two independent but virtually identical molecules comprise the asymmetric unit of the title compound, [Sn(C3H6NO)I3]. The CI3O coordination geometry around the SnIV atom is defined by a chelating carbamoylethyl ligand (C
1,O-bidentate) and three I atoms, and is based on a distorted trigonal bipyramid with the carbonyl O atom occupying a position trans to one of the I atoms which forms the longer of the Sn—I bonds. The independent molecules are linked via N—H⋯O hydrogen bonds, which leads to the formation on an eight-membered amide {⋯HNCO}2 synthon. N—H⋯I hydrogen-bonding interactions are also present between neighbouring molecules
(2,2′-Bipyridine-κ2 N,N′)chlorido(2-hydroxy-2,2-diphenylacetato-κ2 O 1,O 1′)copper(II)
The Cu(II) atom in the title complex, [Cu(C14H11O3)Cl(C10H8N2)], exists within a ClN2O2 donor set defined by a chloride ion, an asymmetrically chelating carboxylate ligand, and a symmetrically chelating 2,2′-bipyridine molecule. The coordination geometry is square pyramidal with the axial site occupied by the O atom forming the weaker Cu—O interaction. The hydroxy group forms an intramolecular hydrogen bond with the axial O atom, as well as an intermolecular O—H⋯Cl hydrogen bond. The latter leads to the formation of [100] supramolecular chains in the crystal, with the Cu(II) atoms lying in a line
Improving our understanding of metal implant failures: Multiscale chemical imaging of exogenous metals in ex-vivo biological tissues
Biological exposures to micro- and nano-scale exogenous metal particles generated as a consequence of in-service degradation of orthopaedic prosthetics can result in severe adverse tissues reactions. However, individual reactions are highly variable and are not easily predicted, due to in part a lack of understanding of the speciation of the metal-stimuli which dictates cellular interactions and toxicity. Investigating the chemistry of implant derived metallic particles in biological tissue samples is complicated by small feature sizes, low concentrations and often a heterogeneous speciation and distribution. These challenges were addressed by developing a multi-scale two-dimensional X-ray absorption spectroscopic (XAS) mapping approach to discriminate sub-micron changes in particulate chemistry within ex-vivo tissues associated with failed CoCrMo total hip replacements (THRs). As a result, in the context of THRs, we demonstrate much greater variation in Cr chemistry within tissues compared with previous reports. Cr compounds including phosphate, hydroxide, oxide, metal and organic complexes were observed and correlated with Co and Mo distributions. This variability may help explain the lack of agreement between biological responses observed in experimental exposure models and clinical outcomes. The multi-scale 2D XAS mapping approach presents an essential tool in discriminating the chemistry in dilute biological systems where speciation heterogeneity is expected. Significance: Metal implants are routinely used in healthcare but may fail following degradation in the body. Although specific implants can be identified as ‘high-risk’, our analysis of failures is limited by a lack of understanding of the chemistry of implant metals within the peri-prosthetic milieu. A new approach to identify the speciation and variability in speciation at sub-micron resolution, of dilute exogenous metals within biological tissues is reported; applied to understanding the failure of metallic (CoCrMo) total-hip-replacements widely used in orthopedic surgery. Much greater variation in Cr chemistry was observed compared with previous reports and included phosphate, hydroxide, oxide, metal and organic complexes. This variability may explain lack of agreement between biological responses observed in experimental exposure models and clinical outcomes
The Atacama Cosmology Telescope: Two-Season ACTPol Lensing Power Spectrum
We report a measurement of the power spectrum of cosmic microwave background
(CMB) lensing from two seasons of Atacama Cosmology Telescope Polarimeter
(ACTPol) CMB data. The CMB lensing power spectrum is extracted from both
temperature and polarization data using quadratic estimators. We obtain results
that are consistent with the expectation from the best-fit Planck LCDM model
over a range of multipoles L=80-2100, with an amplitude of lensing A_lens =
1.06 +/- 0.15 (stat.) +/- 0.06 (sys.) relative to Planck. Our measurement of
the CMB lensing power spectrum gives sigma_8 Omega_m^0.25 = 0.643 +/- 0.054;
including baryon acoustic oscillation scale data, we constrain the amplitude of
density fluctuations to be sigma_8 = 0.831 +/- 0.053. We also update
constraints on the neutrino mass sum. We verify our lensing measurement with a
number of null tests and systematic checks, finding no evidence of significant
systematic errors. This measurement relies on a small fraction of the ACTPol
data already taken; more precise lensing results can therefore be expected from
the full ACTPol dataset.Comment: 17 pages, 11 figures, to be submitted to Physical Review
A measurement of the millimetre emission and the Sunyaev-Zel'dovich effect associated with low-frequency radio sources
We present a statistical analysis of the millimetre-wavelength properties of 1.4GHz-selected sources and a detection of the Sunyaev–Zel’dovich (SZ) effect associated with the haloes that host them. We stack data at 148, 218 and 277GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4GHz. The thermal SZ effect associated with the haloes that host the AGN is detected at the 5σ level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass haloes (average M 200 ≈ 10 13 M. h −1 70 ) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous haloes. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyse the contribution of radio sources to the angular power spectrum of the cosmic microwave background
"I really should've gone to the doctor": older adults and family caregivers describe their experiences with community-acquired pneumonia
BACKGROUND: Responding to acute illness symptoms can often be challenging for older adults. The primary objective of this study was to describe how community-dwelling older adults and their family members responded to symptoms of community-acquired pneumonia (CAP). METHODS: A qualitative study that used face-to-face semi-structured interviews to collect data from a purposeful sample of seniors aged 60+ and their family members living in a mid-sized Canadian city. Data analysis began with descriptive and interpretive coding, then advanced as the research team repeatedly compared emerging thematic categories to the raw data. Searches for disconfirming evidence and member checking through focus groups provided additional data and helped ensure rigour. RESULTS: Community-acquired pneumonia symptoms varied greatly among older adults, making decisions to seek care difficult for them and their family members. Both groups took varying amounts of time as they attempted to sort out what was wrong and then determine how best to respond. Even after they concluded something was wrong, older adults with confirmed pneumonia continued to wait for days, to over a week, before seeking medical care. Participants provided diverse reasons for this delay, including fear, social obligations (work, family, leisure), and accessibility barriers (time, place, systemic). Several older adults and family members regretted their delays in seeking help. CONCLUSION: Treatment-seeking delay is a variable, multi-phased decision-making process that incorporates symptom assessment plus psychosocial and situational factors. Public health and health care professionals need to educate older adults about the potential causes and consequences of unnecessary waits. Such efforts may reduce the severity of community-acquired pneumonia upon presentation at clinics and hospitals, and that, in turn, could potentially improve health outcomes
The Atacama Cosmology Telescope: Two-Season ACTPol Spectra and Parameters
We present the temperature and polarization angular power spectra measured by
the Atacama Cosmology Telescope Polarimeter (ACTPol). We analyze night-time
data collected during 2013-14 using two detector arrays at 149 GHz, from 548
deg of sky on the celestial equator. We use these spectra, and the spectra
measured with the MBAC camera on ACT from 2008-10, in combination with Planck
and WMAP data to estimate cosmological parameters from the temperature,
polarization, and temperature-polarization cross-correlations. We find the new
ACTPol data to be consistent with the LCDM model. The ACTPol
temperature-polarization cross-spectrum now provides stronger constraints on
multiple parameters than the ACTPol temperature spectrum, including the baryon
density, the acoustic peak angular scale, and the derived Hubble constant.
Adding the new data to planck temperature data tightens the limits on damping
tail parameters, for example reducing the joint uncertainty on the number of
neutrino species and the primordial helium fraction by 20%.Comment: 23 pages, 25 figure
A Measurement of the Millimeter Emission and the Sunyaev-Zel'dovich Effect Associated with Low-Frequency Radio Sources
We present a statistical analysis of the millimeter-wavelength properties of 1.4 GHz-selected sources and a detection of the Sunyaev-Zel'dovich effect associated with the halos that host them. We stack data at 148, 218 and 277 GHz from the Atacama Cosmology Telescope at the positions of a large sample of radio AGN selected at 1.4 GHz. The thermal Sunyaev-Zel'dovich (SZ) effect associated with the halos that host the AGN is detected at the 5 sigma level through its spectral signature, representing a statistical detection of the SZ effect in some of the lowest mass halos (average M(sub 200) approximately equals 10(sup 13) solar mass h(sub 70)(exp 1) ) studied to date. The relation between the SZ effect and mass (based on weak lensing measurements of radio galaxies) is consistent with that measured by Planck for local bright galaxies. In the context of galaxy evolution models, this study confirms that galaxies with radio AGN also typically support hot gaseous halos. Adding Herschel observations allows us to show that the SZ signal is not significantly contaminated by dust emission. Finally, we analyze the contribution of radio sources to the angular power spectrum of the cosmic microwave background
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