2,449 research outputs found

    Living Alone and Living with Children: The Living Arrangements of Canadian and Chinese-Canadian Seniors

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    Living arrangements have the potential to tell us far more than simply who lives with whom. Whether a senior lives alone, with a spouse, or with children will provide potentially distinct social support possibilities. From a policy perspective, the particular mix of these living arrangements also provides clues to the need for formal services. While work has been done on how income, gender and age shape the living arrangements of Canadian seniors, relatively little research has explored how ethnicity, language skill and immigration status further mediate living arrangements. Given the future combination of population aging and continued shifts in the source and type of immigration to Canada, additional research on how ethnicity and factors associated with immigration affect living arrangements is also warranted. In this paper I explore the relationship between characteristics of Canadian seniors and their living arrangements. Ethnicity and immigration are further explored by focussing on the living arrangements of Chinese-Canadian seniors. Data for Canadians aged 55 and older from the 1996 individual census Public Use Microdata File (PUMF) (n=159,361), General Social Survey Cycle 11 (GSS11) (n=12,756) and National Population Health Survey (NPHS) (n=13,363) were used in this analysis. Logistic regressions using the PUMF and GSS11 data suggest that while personal income and characteristics of immigrants play important roles in encouraging living alone among older Canadians, their effects do not nullify the role of culture among Chinese- Canadian seniors. Importantly, these effects vary substantially by gender and age. These findings underscore the heterogeneity of Canadian seniors, which is often overlooked in the design and delivery of services to this segment of the population.seniors; living arrangements; PUMF; GSS; NPHS

    Geographic Dimensions of Aging in Canada 1991-2001

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    Although population aging at the national level has received much attention, its geographical dimensions have not. Here we explore the demographic processes which underlie population aging at the provincial and metropolitan scale for the periods 1991-1996 and 1996-2001. A demographic accounting framework is proposed which differentiates between the effects of aging-in-place and net migration on population aging. We also examine the relationships between the various measures of aging and social and economic characteristics of metropolitan areas over the two periods. We demonstrate that the path of population aging is susceptible to social and economic context; in particular, the struggles of the British Columbian economy in the second half of the decade and the deteriorating economies of older resources based communities are associated with increases in population aging over and above the general aging taking place in Canadian society.population aging; geographic differences

    Changing Income Inequality and Immigration in Canada 1980-1995

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    While there is a general consensus that income inequality has increased in most developed countries over the last two decades, the analytical focus has been at the national scale. However, these increases in inequality have not been uniform across different segments of society, either in terms of social group or geographic region. In particular, the high levels of immigration to metropolitan Canada have contributed to growing inequality. Using micro-level data on household income from the 1981,1986,1991 and 1996 censuses, this paper identifies the role of immigration and its differential impact on metropolitan and non-metropolitan areas. The impacts accelerated during the first half of the 1990s when immigration remained high yet the economy slowed. The evidence suggests that the overall impact of immigration is a relatively short-run phenomenon as recent immigrants take time to adjust to the labour market. If recent immigrants are excluded, inequality is still increasing, but at a slower rate, especially in the largest metropolitan areas.income inequality; immigration

    Implications of sperm banking for health-related quality of life up to 1 year after cancer diagnosis.

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    Sperm banking is recommended for all men diagnosed with cancer where treatment is associated with risk of long-term gonadatoxicity, to offer the opportunity of fatherhood and improved quality of life. However, uptake of sperm banking is lower than expected and little is known about why men refuse. Our aims were to determine: (i) demographic and medical variables associated with decisions about banking and (ii) differences in quality of life between bankers and non-bankers at diagnosis (Time 1 (T1)) and 1 year later (Time 2 (T2))

    Studying the nuts and bolts of spermatozoa

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    Hydrodynamic propulsion of human sperm

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    The detailed fluid mechanics of sperm propulsion are fundamental to our understanding of reproduction. In this paper, we aim to model a human sperm swimming in a microscope slide chamber. We model the sperm itself by a distribution of regularized stokeslets over an ellipsoidal sperm head and along an infinitesimally thin flagellum. The slide chamber walls are modelled as parallel plates, also discretized by a distribution of regularized stokeslets. The sperm flagellar motion, used in our model, is obtained by digital microscopy of human sperm swimming in slide chambers. We compare the results of our simulation with previous numerical studies of flagellar propulsion, and compare our computations of sperm kinematics with those of the actual sperm measured by digital microscopy. We find that there is an excellent quantitative match of transverse and angular velocities between our simulations and experimental measurements of sperm. We also find a good qualitative match of longitudinal velocities and computed tracks with those measured in our experiment. Our computations of average sperm power consumption fall within the range obtained by other authors. We use the hydrodynamic model, and a prototype flagellar motion derived from experiment, as a predictive tool, and investigate how sperm kinematics are affected by changes to head morphology, as human sperm have large variability in head size and shape. Results are shown which indicate the increase in predicted straight-line velocity of the sperm as the head width is reduced and the increase in lateral movement as the head length is reduced. Predicted power consumption, however, shows a minimum close to the normal head aspect ratio

    Changing Income Inequality and the Elderly in Canada 1991-1996: Provincial Metropolitan and Local Dimensions

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    Recently, much attention has been given to income inequality in industrialized societies, in part because of the empirical evidence linking high levels of income inequality with high mortality, morbidity and other social ills (Wilkinson, 1996). Analyses of these relations originally focused on national figures, but more recent work has explored these linkages at subnational scales -- for state, provincial and metropolitan entities. At the same time, other studies have documented the recent increases in income inequality during the 1990s in Canada, which raises further questions about the dynamics of the relation between income inequality and its social consequences. In this paper we explore additional dimensions of the structure and change of income inequality in Canada between 1991 and 1996. We examine changing income inequality for the population over 65 as well as for the population as a whole, demonstrating that increases in income inequality are concentrated among those in the labour force years and that there has been little change (even some decline) in income inequality among the elderly. From a geographical perspective, increasing income inequality is significantly a large metropolitan issue and, as such, has a lesser impact on seniors as seniors are relatively more concentrated in smaller urban and rural areas. The fact that income inequality can change quite rapidly at the small area level raises some questions about the links to population health. Population health tends to be cumulative and reflects longer term rather than short-term circumstances. The empirical linkages need significantly more exploration to assess the mechanisms which underlie the observed relationships.income inequality; elderly

    Evidence for Rapid Oxidative Phosphorylation and Lactate Fermentation in Motile Human Sperm by Hyperpolarized 13C Magnetic Resonance Spectroscopy

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    Poor sperm motility is a common cause of male infertility for which there are no empirical therapies. Sperm motility is powered by adenosine triphosphate but the relative importance of lactate fermentation and Oxidative Phosphorylation (OxPhos) is debated. To study the relationship between energy metabolism and sperm motility we used dissolution Dynamic Nuclear Polarization (dDNP) for the first time to show the rapid conversion of 13C1-pyruvate to lactate and bicarbonate, indicating active glycolytic and OxPhos metabolism in sperm. The magnitude of both lactate and bicarbonate signals were positively correlated with the concentration of progressively motile sperm. After controlling for sperm concentration, increased progressive sperm motility generated more pyruvate conversion to lactate and bicarbonate. The technique of dDNP allows ‘snapshots’ of sperm metabolism to be tracked over the different stages of their life. This may provide help to uncover the causes of poor sperm motility and suggest new approaches for novel treatments or therapies

    Chlorite and epidote mineral chemistry in porphyry ore systems: a case study of the Northparkes district, NSW, Australia

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    Propylitic alteration, characterized by the occurrence of chlorite and epidote, is typically the most extensive and peripheral alteration facies developed around porphyry ore deposits. However, exploration within this alteration domain is particularly challenging, commonly owing to weak or nonexistent whole-rock geochemical gradients and the fact that similar assemblages can be developed in other geologic settings, particularly during low-grade metamorphism. We document and interpret systematic spatial trends in the chemistry of chlorite and epidote from propylitic alteration around the E48 and E26 porphyry Cu-Au deposits of the Northparkes district, New South Wales, Australia. These trends vary as a function of both distance from hydrothermal centers and alteration paragenesis. The spatial trends identified in porphyry-related chlorite and epidote at Northparkes include (1) a deposit-proximal increase in Ti, As, Sb, and V in epidote and Ti in chlorite, (2) a deposit-distal increase in Co and Li in chlorite and Ba in epidote, and (3) a pronounced halo around deposits in which Mn and Zn in chlorite, as well as Mn, Zn, Pb, and Mg in epidote, are elevated. Chlorite Al/Si ratios and epidote Al/Fe ratios may show behavior similar to that of Mn-Zn or may simply decrease outward, and V and Ni concentrations in chlorite are lowest in the peak Mn-Zn zone. In comparison to porphyry-related samples, chlorite from the regional metamorphic assemblage in the district contains far higher concentrations of Li, Ca, Ba, Pb, and Cu but much less Ti. Similarly, metamorphic epidote contains higher concentrations of Sr, Pb, As, and Sb but less Bi and Ti. These chlorite and epidote compositional trends are the net result of fluid-mineral partitioning under variable physicochemical conditions within a porphyry magmatic-hydrothermal system. They are most easily explained by the contribution of spent magmatic-derived ore fluid(s) into the propylitic domain. It is envisaged that such fluids experience progressive cooling and reduction in fs2 during outward infiltration into surrounding country rocks, with their pH controlled by the extent of rock-buffering experienced along the fluid pathway

    Effects of virtual reality erotica on ejaculate quality of sperm donors: a balanced and randomized controlled cross-over within-subjects trial

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    Background Previous research has shown that the type and duration of erotic material that men have access to during masturbation can influence semen parameters. To our knowledge, the use of virtual reality (VR) headsets to present erotica has not previously been studied. We reasoned that, because VR can provide a more immersive experience to the user, semen parameters of masturbatory ejaculates may be altered. Methods This study had a balanced and randomized controlled cross-over within-subjects design. 504 ejaculates were collected from 63 sperm donors at 4 locations in Denmark. During masturbation each donor was instructed to observe erotic material either on a touch screen monitor or using a VR headset. The order of each pair of within-subject treatments was randomized by the throw of a dice. Anonymized data were analysed with linear mixed and piecewise structural equation models. Results Both abstinence period and VR-use influenced the total number of motile spermatozoa ejaculated. For short abstinence periods, VR-use increased the number of motile sperm in the ejaculate. However, the difference between VR and non-VR ejaculates decreased as abstinence period increased such that there was no difference at the mean abstinence period of 58 h. For longer abstinence periods, total motile sperm counts were lower, on average, when men used VR compared to those that did not. Conclusion The use of VR headsets to view erotica had a strong positive effect on the number of motile sperm in an ejaculate when the donor’s abstinence time was short (< 24 h). VR-use could improve the ejaculate quality of men who are asked to provide samples after a short period of abstinence, such as men in infertile partnerships producing samples for ART or cancer patients depositing sperm before treatment
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