1,290 research outputs found
Turning up the lights - fabrication of brighter SERRS nanotags
Brighter SERRS nanotags ideal for improved SERRS imaging were prepared by the controlled addition of electrolyte producing a dimer enriched solution, which was incubated with a Raman reporter before being stabilised by a polyethylene glycol (PEG) shell
The Elliptical Galaxy formerly known as the Local Group: Merging the Globular Cluster Systems
Prompted by a new catalogue of M31 globular clusters, we have collected
together individual metallicity values for globular clusters in the Local
Group. Although we briefly describe the globular cluster systems of the
individual Local Group galaxies, the main thrust of our paper is to examine the
collective properties. In this way we are simulating the dissipationless merger
of the Local Group, into presumably an elliptical galaxy. Such a merger is
dominated by the Milky Way and M31, which appear to be fairly typical examples
of globular cluster systems of spiral galaxies.
The Local Group `Elliptical' has about 700 +/- 125 globular clusters, with a
luminosity function resembling the `universal' one. The metallicity
distribution has peaks at [Fe/H] ~ -1.55 and -0.64 with a metal-poor to
metal-rich ratio of 2.5:1. The specific frequency of the Local Group Elliptical
is initially about 1 but rises to about 3, when the young stellar populations
fade and the galaxy resembles an old elliptical. The metallicity distribution
and stellar population corrected specific frequency are similar to that of some
known early type galaxies. Based on our results, we briefly speculate on the
origin of globular cluster systems in galaxies.Comment: 22 pages, Latex, 4 figures, 5 tables, submitted to A &
Research Brief No. 12 - The effect of work arrangements on perceived work-family balance
The combined demands of the modern work world and raising a healthy family have many Canadian struggling to find enough time. Canadians are working more and more hours while wages largely remain stagnant. In order to address this growing concern, alternate work arrangements have been increasingly used to help employees strike some degree of work-family balance and decrease related issues of absenteeism and turnover in the workplace. This research explores the effect of three unique work strategies — flexible schedules, shift work and self-employment — on men and women in dual-earner families. It examines each arrangement’s impact on reported satisfaction with balance between family and work lives. Results indicate that using flexible schedules and increasing employees’ enjoyment of their work can help promote work-family balance
Multiple peripheral pneumococcal mycotic aneurysms without aortic involvement: A unique case confirmed with the novel use of a molecular diagnostic technique
Mycotic aneurysms confer a high morbidity and mortality. Streptococcus pneumoniae aneurysms usually affect the aorta and are rare, although bacterial cultures from aneurysm tissue may be difficult following prior antimicrobial therapy. We report a unique case of mycotic femoral and popliteal artery aneurysms following pneumococcal pneumonia and meningitis, which were managed by resection, revascularization with autologous vein, and intravenous benzylpenicillin. Although blood and aneurysm sac cultures were negative, arterial wall S pneumoniae DNA was detected by polymerase chain reaction (PCR). Appropriate molecular diagnostic techniques can facilitate diagnosis and direct antimicrobial therapy; an important consideration with increasing antimicrobial resistance
Mixed-conducting oxygen permeable ceramic membranes for the carbon dioxide reforming of methane
This is the published version. Copyright 2007 Royal Society of ChemistryDue to the high economic, environmental, and safety costs associated with pure oxygen, mixed-conducting oxygen-permeable ceramic membranes are being explored as an alternative oxygen source for hydrocarbon conversion reactors. This work reports a dramatic improvement in catalyst performance when an oxygen-permeable SrFeCo0.5Ox ceramic membrane is used in conjunction with a conventional powder Pt/ZrO2 catalyst for the CO2 reforming of CH4. Experiments comparing catalyst performance with up to 2% co-fed oxygen to catalyst performance with oxygen from the ceramic membrane demonstrated a conversion three times higher with the membrane than with any amount of co-fed oxygen. The results suggest that membrane oxygen is more beneficial for catalyst activity and stability than molecular gas-phase oxygen
The impact of COVID-19 on access to canine integrative medical care in Michigan, USA, and Ontario and British Columbia, Canada,:Canine integrative medical care and COVID-19
Visual search for featural singletons: No top-down modulation, only bottom-up priming.
The present study investigated the effect of top-down knowledge on search for a feature singleton (a "pop-out target"). In a singleton detection task, advance cueing of the dimension of upcoming singleton resulted in cueing costs and benefits (Experiment 1). When the search for the singleton stayed the same but only the response requirements were changed, advance cueing failed to have an effect (Experiments 2 and 3). In singleton search only bottom-up priming plays a role (Experiments 4 and 5). We conclude that expectancy-based, top-down knowledge cannot guide the search for a featural singleton. Bottom-up priming that does facilitate search for a featural singleton cannot be influenced by top-down control. The study demonstrates that effects often attributed to early top-down guidance may represent effects that occur later in processing or represent bottom-up priming effects. © 2006 Psychology Press Ltd
Investigation of the middle corona with SWAP and a data-driven non-potential coronal magnetic field model
The large field-of-view of the Sun Watcher using Active Pixel System detector and Image Processing (SWAP) instrument onboard the PRoject for Onboard Autonomy 2 (PROBA2) spacecraft provides a unique opportunity to study extended coronal structures observed in the EUV in conjunction with global coronal magnetic field simulations. A global non-potential magnetic field model is used to simulate the evolution of the global corona from 1 September 2014 to 31 March 2015, driven by newly emerging bipolar active regions determined from Helioseismic and Magnetic Imager (HMI) magnetograms. We compare the large-scale structure of the simulated magnetic field with structures seen off-limb in SWAP EUV observations. In particular, we investigate how successful the model is in reproducing regions of closed and open structures, the scale of structures, and compare the evolution of a coronal fan observed over several rotations. The model is found to accurately reproduce observed large-scale, off-limb structures. When discrepancies do arise they mainly occur off the east solar limb due to active regions emerging on the far side of the Sun, which cannot be incorporated into the model until they are observed on the Earth-facing side. When such “late” active region emergences are incorporated into the model, we find that the simulated corona self-corrects within a few days, so that simulated structures off the west limb more closely match what is observed. Where the model is less successful, we consider how this may be addressed, through model developments or additional observational products
Nutritional status, growth and disease management in children with single and dual diagnosis of type 1 diabetes mellitus and coeliac disease
Background:
The consequences of subclinical coeliac disease (CD) in Type 1 diabetes mellitus (T1DM) remain unclear. We looked at growth, anthropometry and disease management in children with dual diagnosis (T1DM + CD) before and after CD diagnosis.<p></p>
Methods:
Anthropometry, glycated haemoglobin (HbA1c) and IgA tissue transglutaminase (tTg) were collected prior to, and following CD diagnosis in 23 children with T1DM + CD. This group was matched for demographics, T1DM duration, age at CD diagnosis and at T1DM onset with 23 CD and 44 T1DM controls.<p></p>
Results:
No differences in growth or anthropometry were found between children with T1DM + CD and controls at any time point. Children with T1DM + CD, had higher BMI z-score two years prior to, than at CD diagnosis (p <0.001). BMI z-score change one year prior to CD diagnosis was lower in the T1DM + CD than the T1DM group (p = 0.009). At two years, height velocity and change in BMI z-scores were similar in all groups. No differences were observed in HbA1c between the T1DM + CD and T1DM groups before or after CD diagnosis. More children with T1DM + CD had raised tTg levels one year after CD diagnosis than CD controls (CDx to CDx + 1 yr; T1DM + CD: 100% to 71%, p = 0.180 and CD: 100% to 45%, p < 0.001); by two years there was no difference.<p></p>
Conclusions:
No major nutrition or growth deficits were observed in children with T1DM + CD. CD diagnosis does not impact on T1DM glycaemic control. CD specific serology was comparable to children with single CD, but those with dual diagnosis may need more time to adjust to gluten free diet
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