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This study examines the distribution options of 85 large public retirement plans covering general state employees, teachers, and local government employees. The interest rates used to price annuities vary considerably across the plans. As a result, retirees with the same monthly benefit if a single life benefit is chosen will have substantially different monthly benefits if they select a joint and survivor annuity. We examine the impact of variation in the pricing of annuity options using both cross-plan differences in interest rates and the change in the choice of annuity options in one plan after the price of options changes due to new assumed interest rates and mortality rates.
To estimate the prevalence and sociodemographic characteristics of youth and young adults in major Canadian cities with self-reported vegetarian dietary practices and examine efforts to alter their diets.
Data were collected in autumn 2016 via web-based surveys. Respondents reported vegetarian dietary practices (vegan, vegetarian or pescatarian) and efforts in the preceding year to consume more or less of several nutrients, food groups and/or foods with particular attributes. Logistic regression models examined sociodemographic correlates of each vegetarian dietary practice and differences in other eating practices by diet type.
Participants were recruited from five major Canadian cities.
Youth and young adults, aged 16–30 years (n 2566).
Overall, 13·6 % of respondents reported vegetarian dietary practices: 6·6 % vegetarian, 4·5 % pescatarian and 2·5 % vegan. Sex, race/ethnicity, self-reported frequency of using the Nutrition Facts table and health literacy were significantly correlated with self-reported vegetarian dietary practice (P < 0·01 for all). Efforts to consume more fruits and vegetables (66·8 %) and protein (54·8 %), and less sugar (61·3 %) and processed foods (54·7 %), were prevalent overall. Respondents with vegetarian dietary practices were more likely to report efforts to consume fewer carbohydrates and animal products, and more organic, locally produced, ethically sourced/sustainably sourced/fair trade and non-GM foods (P < 0·01 for all), compared with those without these reported dietary practices.
Nearly 14 % of the sampled youth and young adults in major Canadian cities reported vegetarian dietary practices and may be especially likely to value and engage in behaviours related to health-conscious diets and sustainable food production.
This is a copy of the slides presented at the meeting but not formally written up for the volume.
We have studied the effects of epitaxial strains on structural phase transition behavior of fully-commensurate single crystal thin films of SrRuO3 using in situ temperature-dependent reflection high-energy electron diffraction (RHEED) and ex situ temperature-dependent x-ray diffraction (XRD) measurements. From RHEED measurements on compressively-strained (110) SrRuO3 grown on (001) SrTiO3 substrate, it was found that the surface of SrRuO3 showed no orthorhombic distortion even at room temperature (25°C) below the thickness of 10 monolayers (MLs). The orthorhombic transition temperature (TC) was determined to be 90°C at the thickness of 13 ML;s and then systematically increased up to 238°C at 35 ML. More interestingly, however, tensilely-strained SrRuO3 films grown on (110) DyScO3 and (110) GdScO3 substrates have simple cubic perovskite structure at room temperature irrespectively of SrRuO3 thicknesses. The shift of TC is very dramatic, considering that the orthorhombic transition temperature of SrRuO3 is known to be 547°C in bulk form. These unique transition behaviors were also confirmed by temperature-dependent four-circle x-ray diffraction measurements. TC of 35 ML thick SrRuO3 on SrTiO3 were determined to be 250°C and which was consistent with that determined from RHEED measurements.
Choices regarding the disposition of wealth at retirement can have substantial implications for retirement income security. We analyze the factors determining annuity payout option choices within the context of a public sector defined pension plan with no default annuity option. Using combined administrative records and survey data, we explore the role of individual and household characteristics as well as risk preferences, time preferences, and financial literacy. We also document retiree well-being and satisfaction with retirement decision making. The evidence is consistent with predictions over which households might benefit most from each annuity option. Comparing retirees who chose different types of annuities, we find that these groups of retirees report very different levels of well-being in retirement. All retirees report lower levels of retirement income security over time, with strong differences among those who chose different types of annuities.
To examine the potential links between activity spaces, the food retail environment and food shopping behaviours for the population of young, urban adults.
Participants took part in the Canada Food Study, which collected information on demographics, food behaviour, diet and health, as well as an additional smartphone study that included a seven-day period of logging GPS (global positioning system) location and food purchases. Using a time-weighted, continuous representation of participant activity spaces generated from GPS trajectory data, the locations of food purchases and a geocoded food retail data set, negative binomial regression models were used to explore what types of food retailers participants were exposed to and where food purchases were made.
Toronto, Montreal, Vancouver, Edmonton and Halifax, Canada.
Young adults aged 16–30 years (n 496). These participants were a subset of the larger Canada Food Study.
Demographics, household food shopper status and city of residence were significantly associated with different levels of exposure to various types of food retailers. Food shopping behaviours were also statistically significantly associated with demographics, the activity space-based food environment, self-reported health and city of residence.
The study confirms that food behaviours are related to activity space-based food environment measures, which provide a more comprehensive accounting of food retail exposure than home-based measures. In addition, exposure to food retail and food purchasing behaviours of an understudied population are described.
Characterisation of genetic diversity in a large number of European pig populations has been undertaken with EC support. The populations sampled included local (rare) breeds, national varieties of the major international breeds, commercial lines and the Chinese Meishan breed. A second phase of the project will sample a further 50 Chinese breeds. Neutral genetic markers (AFLP and microsatellites), with individual or bulk typing, were used and compared.
DNA from 59 European pig populations was extracted on samples of about 50 individuals per population. Individuals were typed for 50 microsatellites and for 148 AFLP bands. A subset of 25 populations was typed for 20 microsatellites on pools of DNA. Allele frequencies were estimated by direct allele counting for the co-dominant markers. Frequencies of AFLP negative alleles (absent bands) were obtained by taking the square root of absent band frequencies. Within-breed variability was summarised using standard statistics: expected and observed heterozygosity, mean observed and effective numbers of alleles, and F statistics. Between-breed diversity analysis was based on a bootstrapped Neighbor-Joining (NJ) tree derived from Reynolds distances (DR). The standard distance of Nei (DS) was also calculated.
The effects of Reynolds number (
) and Stokes number (
) on particle-pair relative velocity (RV) are investigated systematically using a recently developed planar four-frame particle tracking technique in a novel homogeneous and isotropic turbulence chamber. We compare the measured results with direct numerical simulation (DNS), verifying whether the conclusions of the DNS for simplified conditions and limited
are still valid in reality. Two experiments are performed: varying
between 246 and 357 at six
values, and varying
between 0.02 and 4.63 at five
values. The measured mean inward particle-pair RV
as a function of separation distance
is compared with the DNS under closely matched conditions. At all experimental conditions, an excellent agreement is achieved, except when the particle separation distance
is the Kolmogorov length scale), where the experimental
is consistently higher, possibly due to particle polydispersity and finite laser thickness in the experiments (Dou et al., arXiv:1712.07506, 2017). At any fixed
is essentially independent of
, echoing the DNS finding of Ireland et al. (J. Fluid Mech., vol. 796, 2016, pp. 617–658). At any fixed
, showing dominance of the path-history effect in the dissipation range when
, but decreases with
, indicating dominance of inertial filtering. We further compare the
and RV variance
from experiments with DNS and theoretical predictions by Pan & Padoan (J. Fluid Mech., vol. 661, 2010, pp. 73–107). For
match these values well at
, but they are higher than both DNS and theory at
from all three match well, except for
, for which experimental values are higher, while
from experiment and DNS are much higher than theoretical predictions. We discuss potential causes of these discrepancies. What this study shows is the first experimental validation of
effect on inertial particle-pair
in homogeneous and isotropic turbulence.
For social movements, coverage in the media is a mixed blessing; but like many movements, the Brazilian Landless Farmworkers' Movement (MST) actively seeks it out. Treatment of the MST in the Brazilian media is analyzed here using the concept of frame. That treatment is determined by a complex interaction between media producers and movement activists. The frames adopted by those on each side influence public perception of the movement. This study identifies five such underlying frames (mostly in print media but with attention to a television soap opera based on the MST's activities) and examines the images of the movement that they present. Though the coverage often presents the MST in a favorable light, it does not necessarily encourage the goal of mobilization that the movement seeks to promote.
Adipose tissue becomes more saturated and less unsaturated with age (Kemp et al., 1981). Desaturation of stearic acid to the oleic acid is catalysed by stearoyl-CoA desaturase (SCD) and increasing the degree of desaturation of lamb is likely to be beneficial in terms of human nutrition. By altering the levels of ovine SCD mRNA, the supply of oleic acid to the tissue could be manipulated, resulting in a practical method of changing the fatty acid profile of the animals meat. Previous work in our laboratory has shown variability between adipose tissue depots in their expression of SCD and that this variability is associated with changes in oleic acid content (Daniel et al, 2004). Such differences in SCD expression between depots implies that there may be even larger variation in SCD expression between breeds. A sheep breed with particularly high level of SCD mRNA could then be exploited through breeding programmes to produce animals with increased desaturase activity and therefore increased oleic acid content. Three sheep breeds, Texel, Beulah and Soay, were therefore used to study the influence of breed and age on SCD expression.
To examine exposure to energy drink marketing among youth and young adults, and test perceptions of energy drink advertisements (ads) regarding target audience age and promoting energy drink use during sports.
A between-group experiment randomly assigned respondents to view one of four energy drink ads (sport-themed or control) and assessed perceptions of the ad. Regression models examined marketing exposure and perceptions.
Online survey (2014).
Canadians aged 12–24 years (n 2040) from a commercial panel.
Overall, 83 % reported ever seeing energy drink ads through at least one channel, including on television (60 %), posters/signs in stores (49 %) and online (44 %). Across experimental conditions, most respondents (70·1 %) thought the ad they viewed targeted people their age or younger, including 42·2 % of those aged 12–14 years. Two sport-themed ads were more likely to be perceived as targeting a younger audience (adjusted OR (95 % CI): ‘X Games’ 36·5 %, 4·16 (3·00, 5·77); ‘snowboard’ 19·2 %, 1·50 (1·06, 2·13)) v. control (13·3 %). Participants were more likely to believe an ad promoted energy drink use during sports if they viewed any sport-themed ad (‘X Games’ 69·9 %, 8·29 (6·24, 11·02); ‘snowboard’ 76·7 %, 11·85 (8·82, 15·92); ‘gym’ 66·8 %, 7·29 (5·52, 9·64)) v. control (22·0 %). Greater reported exposure to energy drink marketing was associated with perceiving study ads as promoting energy drink use during sports.
Energy drink marketing has a high reach among young people. Ads for energy drinks were perceived as targeting youth and promoting use during sports. Such ads may be perceived as making physical performance claims, counter to Canadian regulations.
Objectives: The present study constitutes the first randomized controlled trial to investigate the relation of lutein (L) and zeaxanthin (Z) to brain function using functional magnetic resonance imaging (fMRI). It was hypothesized that L and Z supplementation in older adults would enhance neural efficiency (i.e., reduce activation) and cognitive performance on a verbal learning task relative to placebo. Methods: A total of 44 community-dwelling older adults (mean age=72 years) were randomly assigned to receive either placebo or L+Z supplementation (12 mg/daily) for 1 year. Neurocognitive performance was assessed at baseline and post-intervention on an fMRI-adapted task involving learning and recalling word pairs. Imaging contrasts of blood-oxygen-level-dependent (BOLD) signal were created by subtracting active control trials from learning and recall trials. A flexible factorial model was employed to investigate the expected group (placebo vs. supplement) by time (baseline vs. post-intervention) interaction in pre-specified regions-of-interest. Results: L and Z appeared to buffer cognitive decline on the verbal learning task (Cohen’s d=.84). Significant interactions during learning were observed in left dorsolateral prefrontal cortex and anterior cingulate cortex (p < .05, family-wise-error corrected). However, these effects were in the direction of increased rather than decreased BOLD signal. Although the omnibus interaction was not significant during recall, within-group contrasts revealed significant increases in left prefrontal activation in the supplement group only. Conclusions: L and Z supplementation appears to benefit neurocognitive function by enhancing cerebral perfusion, even if consumed for a discrete period of time in late life. (JINS, 2018, 24, 77–90)
We present the first demonstration of a general method for the chemical characterization of small surface features at high magnification via simultaneous collection of mass spectrometry (MS) imaging and tandem MS imaging data. High lateral resolution tandem secondary ion MS imaging is employed to determine the composition of surface features on poly(ethylene terephthalate) (PET) that precipitate during heat treatment. The surface features, probed at a lateral resolving power of<200 nm using a surface-sensitive ion beam, are found to be comprised of ethylene terephthalate trimer at a greater abundance than is observed in the surrounding polymer matrix. This is the first chemical identification of PET surface precipitates made without either an extraction step or the use of a reference material. The new capability employed for this study achieves the highest practical lateral resolution ever reported for tandem MS imaging.
Objectives: It is well known that the carotenoids lutein (L) and zeaxanthin (Z) improve eye health and an accumulating evidence base suggests cognitive benefits as well. The present study investigated underlying neural mechanisms using functional magnetic resonance imaging (fMRI). It was hypothesized that lower L and Z concentrations would be associated with neurobiological inefficiency (i.e., increased activation) during cognitive performance. Methods: Forty-three community-dwelling older adults (mean age=72 years; 58% female; 100% Caucasian) were asked to learn and recall pairs of unrelated words in an fMRI-adapted paradigm. L and Z levels were measured in retina (macular pigment optical density) and serum using validated procedures. Results: Following first-level contrasts of encoding and retrieval trials minus control trials (p<.05, family-wise error corrected, minimum voxel cluster=8), L and Z were found to significantly and negatively relate to blood-oxygen-level-dependent signal in central and parietal operculum cortex, inferior frontal gyrus, supramarginal gyrus, planum polare, frontal and middle temporal gyrus, superior parietal lobule, postcentral gyrus, precentral gyrus, occipital cortex bilaterally, and cerebellar regions. Conclusions: To the authors’ knowledge, the present study represents the first attempt to investigate neural mechanisms underlying the relation of L and Z to cognition using fMRI. The observed results suggest that L and Z promote cognitive functioning in old age by enhancing neural efficiency. (JINS, 2017, 23, 11–22)
In view of the considerable ground covered by the Commission at its Paris meetings and the fairly complete record of the activities of institutes and observatories, etc. published in the Minutes, it has not been deemed profitable by the president to call for further reports in advance of the Stockholm meeting. At the Paris meeting it was agreed that such reports be printed independently before each meeting of the Union and that reprints of or references to the published reports be sent to the president. It is hoped that all such reports if ready will be made available before the Stockholm meeting so that they may be summarized by the representatives in attendance or by the president and recorded in the Minutes. With reference to the pronouncement at the Paris meeting “that it is eminently desirable that more attention be given to the development of accurate general perturbations and mean elements on the basis of accurate osculating elements”, the president has visited the Planeten-Institut at Frankfurt and the Rechen-Institut at Berlin and has been in correspondence with the Leningrad Institute. From these sources particularly valuable material has been received.
Model atmosphere techniques and an experimentally confirmed theory of collision broadening of CaII H and K by helium have been combined to shou that the difference in velocity shifts for the two lines is a sensitive diagnostic for the H/He abundance ratio in cool, metallic line uhite dwarfs.
Sudden release of accreted ice in fuel systems could pose a serious challenge in aircraft operation. The resultant snowshower may reach the filter and fuel-oil heat exchanger, causing a restriction in fuel flow to the engine. It is fundamental to have an appreciation of the character and the interface shear strength of the accreted ice in aircraft fuel systems. This helps to recognise factors for the sudden release of the accreted ice and the intensity of the consequential snowshower. An experimental study was carried out to quantify the character and the interface shear strength of accreted ice on subcooled surfaces submerged in jet fuel. Ice was accreted on naked aluminium, painted aluminium and carbon fibre composite surfaces at various subcooled temperatures. The accreted ice was akin to fresh snow and exhibited soft and fluffy attributes. The character may be expressed quantitatively in terms of the porosity and was found to be c. 0·95. The ice weakly adhered to the substrate surfaces, and the interface shear strength was found to be c. 0·36Pa and c. 2·19Pa at the top surface and at the vertical surface of a specimen block, respectively. It was not possible to detect any variation in the porosity and the interface shear strength for different types of surface finishes and differences in water affnity in fuels due to the crude approach in the estimation of these parameters.
Important contributions to the study of the sarissa and its use in combat have been made recently by Minor M. Markle, III. He has shown clearly that the sarissa proper, a pike varying between fifteen and eighteen feet in the fourth century B.C., was held in action fairly near the butt-end and was wielded with both hands by the infantryman. When the phalanx was in close order, as many as five pike-points might project in front of a front-line man towards the enemy. The front man himself had a reach of some twelve feet with his pike, and he could put his full strength into a two-armed thrust. On the other hand, a Greek spear-man wielded a seven-foot spear with a reach of some four feet (as he held it near the middle) and he thrust only with the strength of one arm (the other arm carrying his large shield, some three feet in diameter). Thus when a pike-phalanx engaged a spear-phalanx, the spear-man was at a great disadvantage; he could not reach his opponent at all until he had himself passed through some three or four pike-points, and even then he could not put as much strength into his thrust as his opponent was able to do.