1,133 research outputs found
Interstellar HOCN in the Galactic center region
Aims. Our aim is to confirm the interstellar detection of cyanic acid, HOCN,
in the Galactic center clouds. It has previously been tentatively detected only
in Sgr B2(OH).
Methods. We used a complete line survey of the hot cores Sgr B2(N) and (M) in
the 3 mm range, complemented by additional observations carried out with the
IRAM 30 m telescope at selected frequencies in the 2 mm band and towards four
additional positions in the Sgr B2 cloud complex in the 2 and 3 mm bands. The
spectral survey was analysed in the local thermodynamical equilibrium
approximation (LTE) by modeling the emission of all identified molecules
simultaneously. This allowed us to distinguish weak features of HOCN from the
rich line spectrum observed in Sgr B2(N) and (M). Lines of the more stable (by
1.1 eV) isomer isocyanic acid, HNCO, in these sources, as well as those of HOCN
and HNCO towards the other positions, were analysed in the LTE approximation as
well.
Results. Four transitions of HOCN were detected in a quiescent molecular
cloud in the Galactic center at a position offset in (R.A., decl.) by
(20'',100'') from the hot core source Sgr B2(M), confirming its previous
tentative interstellar detection. Up to four transitions were detected toward
five other positions in the Sgr B2 complex, including the hot cores Sgr B2(M),
(S), and (N). A fairly constant abundance ratio of ~ 0.3 - 0.8 % for HOCN
relative to HNCO was derived for the extended gas components, suggesting a
common formation process of these isomers
Factors associated with rehoming and time until rehoming for horses listed with an equine charity
The number of unwanted horses in the UK has increased in recent years. It is therefore important to identify factors that indicate whether a horse can be rehomed and how long it takes to be rehomed. Data from 1 January 2013 until 30 March 2014 were extracted from an equine rehoming charity’s database. Exposure variables were examined using multivariable logistic and Cox regression. In total, 791 horses were included in the study and 410 (51.8%) were rehomed during the study period. Median time until rehomed was 39 days (IQR 24–75). Horses whose owner was prepared to transfer ownership were nearly three times more likely to be rehomed than those available for loan. Horses deemed suitable for beginner riders had higher odds of finding a new home, compared with those needing an advanced rider. Horses that were only suitable as unridden companions took longer to find a new home than rideable horses. A restricted rehoming radius (<50 miles) also resulted in longer time to rehoming. Findings from this study can be used to inform rehoming strategies but also to identify horses less likely to be rehomed, and thus where alternative options should be considered
Inferring choice criteria with mixture IRT models: A demonstration using ad hoc and goal-derived categories
Whether it pertains to the foods to buy when one is on a diet, the items to take along to the beach on one’s day off or
(perish the thought) the belongings to save from one’s burning house, choice is ubiquitous. We aim to determine from
choices the criteria individuals use when they select objects from among a set of candidates. In order to do so we employ
a mixture IRT (item-response theory) model that capitalizes on the insights that objects are chosen more often the better
they meet the choice criteria and that the use of different criteria is reflected in inter-individual selection differences. The
model is found to account for the inter-individual selection differences for 10 ad hoc and goal-derived categories. Its
parameters can be related to selection criteria that are frequently thought of in the context of these categories. These
results suggest that mixture IRT models allow one to infer from mere choice behavior the criteria individuals used to
select/discard objects. Potential applications of mixture IRT models in other judgment and decision making contexts are
discussed
Demonstration of silicon-on-insulator mid-infrared spectrometers operating at 3.8µm
The design and characterization of silicon-on-insulator mid- infrared spectrometers operating at 3.8µm is reported. The devices are fabricated on 200mm SOI wafers in a CMOS pilot line. Both arrayed waveguide grating structures and planar concave grating structures were designed and tested. Low insertion loss (1.5-2.5dB) and good crosstalk characteristics (15-20dB) are demonstrated, together with waveguide propagation losses in the range of 3 to 6dB/cm
Epidemiology of diabetes mellitus among 193,435 cats attending primary-care veterinary practices in England
BACKGROUND: Diabetes mellitus (DM) is a common endocrine disease of cats. The prevalence of DM in cats in England is not well‐defined. HYPOTHESIS/OBJECTIVES: To estimate the prevalence and identify risk factors for DM in a large population of cats attending primary‐care practices. ANIMALS: A cohort of 193,563 cats in the VetCompass Programme attending 118 primary‐care practices in England. METHODS: Cross‐sectional analysis of cohort clinical data. Data were extracted covering September 1st 2009 and August 31st 2014. Period prevalence of DM was calculated. Associations between risk factors and DM were assessed using logistic regression modelling. RESULTS: Of 1,128 DM cases were identified among 194,563 cats (period prevalence 0.58%; 95% confidence interval [CI] 0.54–0.61). Multivariable modelling indicated that Tonkinese (OR 4.1; 95% CI 1.8–9.6; P = .001), Norwegian Forest (odds ratio [OR] 3.5; 95% CI 1.3–9.6; P = .001) and Burmese (OR 3.0; 95% CI 2.0–4.4; P < .001) cats had increased odds of DM compared with crossbred cats. DM odds increased as bodyweight categories increased above 4 kg (P < .001), as cats aged beyond 6 years old (P < .001) and in insured cats (OR 2.0; 95% CI 1.6–2.4; P < .001) but sex was not significantly associated with DM. CONCLUSIONS AND CLINICAL IMPORTANCE: Diabetes mellitus is an important component of the primary‐care practice caseload with 1‐in‐200 cats affected. An increased risk of DM in certain cat breeds supports a genetic predisposition. These results can guide future research and preventative healthcare
50GHz Ge waveguide electro-absorption modulator integrated in a 220nm SOI photonics platform
We report waveguide-integrated Ge electro-absorption modulators operating at 1615nm wavelength with 3dB bandwidth beyond 50GHz and a capacitance of 10fF, A 2V voltage swing enables 4.6dB DC extinction ratio for 4.1dB insertion loss
Revealing criterial vagueness in inconsistencies
Sixty undergraduate students made category membership decisions for each of 132
candidate exemplar-category name pairs (e.g., chess – Sports) in each of two separate
sessions. They were frequently inconsistent from one session to the next, both for nominal
categories such as Sports and Fish, and ad hoc categories such as Things You Rescue from
a Burning House. A mixture model analysis revealed that several of these inconsistencies
could be attributed to criterial vagueness: participants adopting different criteria for
membership in the two sessions. This finding indicates that categorization is a probabilistic
process, whereby the conditions for applying a category label are not invariant. Individuals
have various functional meanings of nominal categories at their disposal and entertain
competing goals for ad hoc categories
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