Labour force participation in Canada: Trends and shifts

A key determinant of the potential growth of an economy is the rate at which the labour force increases, which depends both on population growth and on changes in the participation rate. Cyclical factors related to the economic environment can play a significant role in affecting the participation rate, as can structural factors and demographic trends. From the mid-1970s to the end of the 1980s, the participation rate rose almost without interruption to a record high of 67.5 per cent. In contrast, between 1990 and 1995, it declined sharply and has been relatively steady at around 65 per cent since 1995. In this article, the author analyzes the participation rate of age and gender groupings in order to better understand the factors leading to these developments and their implications for future movements in the aggregate rate. While cyclical factors contributed to the decline in the participation rate in the 1990s, structural factors (such as an increase in school attendance rates and the increasing use of computer technology) and demographic trends (the aging of the population) have had a substantial impact. The conclusion reached is that, while some recovery is to be expected, the aggregate participation rate is unlikely to return to its 1989 peak over the next decade or so.

Structural Influences on Participation Rates: A Canada-U.S. Comparison

In contrast to the decline in labour force participation in Canada in the 1990s, the aggregate participation rate in the United States actually rose slightly (up 0.5 percentage points between 1989 and 1997). This US experience provides a useful benchmark for the analysis of the Canadian developments. In the second article of the symposium, Irene Ip, Sheryl King and Geneviève Verdier, while recognizing that cyclical influences have contributed significantly to the decline in labour force participation in the 1990s in Canada relative to the United States, focus on supply-side factors at play in the behviour of the participation rate in the two countries. A key structural variable influencing youth labour force participation is enrolment rates. As the participation rate of students is below that of non-students, increased enrolment tends to reduce aggregate participation. Enrolment rates for teenagers increased 7 percentage points in Canada between 1989 and 1997, and 5 points in the United States; rates for youth adults increased 11 points in Canada and 7 points in the United States. As the U.S. economy enjoyed low unemployment in both 1989 and 1997, the rise in enrolment rates was related to structural factors, such as the growing recognition of the importance of education for success on the job market. Structural factors were undoubtedly at play in Canada . However, the authors suggest that the increase in enrolment rates beyond that experienced in the United States (29 per cent of the increase in enrolment rates for teens and 36 per cent for young adults) may be interpreted as a cyclical response to weak employment opportunities in Canada. The authors find composition changes in the age structure of the population account for about one percentage point of the decline in the aggregate participation rate in Canada between 1989 and 1997, as the relative importance of low-participation rate groups has increased. Based on an analysis of the factors affecting labour force participation of the major age-sex groups, the authors forecast a rise in the aggregate participation rate in Canada from 65.1 per cent in 1998 to 66.6 per cent in 2006. For the United States, the Bureau of Labor Statistics is forecasting a smaller increase, but from a higher level, to 67.6 per cent in 2006 from 67.1 per cent in 1998. The authors expect increases in labour force participation for all age-sex groups in Canada. Between 1998 and 2006, the participation rate is forecast to rise 4.6 percentage points for older men (55 and over), 3.8 points for older women, 3.7 points for prime age women, 8.9 points for teenagers, 3.5 points for young adults, and even 1.0 points for prime-aged men. The 1.5 point increase in the aggregate participation rate is much smaller than almost all the increases in the age-sex group specific rates because of the changing age structure, in particular the increasing proportion of the population in older age groups.Canada, United States, Labour Force Participation, Labor Force Participation, Participation Rate, Labour Force Participation Rate, Labor Force Participation Rate, Age Structure, Age, Sex, Gender, Aging, Ageing

Neuroinflammation by cytotoxic T-lymphocytes impairs retrograde axonal transport in an oligodendrocyte mutant mouse

Mice overexpressing proteolipid protein (PLP) develop a leukodystrophy-like disease involving cytotoxic, CD8+ T-lymphocytes. Here we show that these cytotoxic T-lymphocytes perturb retrograde axonal transport. Using fluorogold stereotactically injected into the colliculus superior, we found that PLP overexpression in oligodendrocytes led to significantly reduced retrograde axonal transport in retina ganglion cell axons. We also observed an accumulation of mitochondria in the juxtaparanodal axonal swellings, indicative for a disturbed axonal transport. PLP overexpression in the absence of T-lymphocytes rescued retrograde axonal transport defects and abolished axonal swellings. Bone marrow transfer from wildtype mice, but not from perforin- or granzyme B-deficient mutants, into lymphocyte-deficient PLP mutant mice led again to impaired axonal transport and the formation of axonal swellings, which are predominantly located at the juxtaparanodal region. This demonstrates that the adaptive immune system, including cytotoxic T-lymphocytes which release perforin and granzyme B, are necessary to perturb axonal integrity in the PLP-transgenic disease model. Based on our observations, so far not attended molecular and cellular players belonging to the immune system should be considered to understand pathogenesis in inherited myelin disorders with progressive axonal damage

Chronic neuropathic pain components in whiplash-associated disorders correlate with metabolite concentrations in the anterior cingulate and dorsolateral prefrontal cortex: a consensus-driven MRS re-examination

IntroductionWhiplash injury (WHI) is characterised by a forced neck flexion/extension, which frequently occurs after motor vehicle collisions. Previous studies characterising differences in brain metabolite concentrations and correlations with neuropathic pain (NP) components with chronic whiplash-associated disorders (WAD) have been demonstrated in affective pain-processing areas such as the anterior cingulate cortex (ACC). However, the detection of a difference in metabolite concentrations within these cortical areas with chronic WAD pain has been elusive. In this study, single-voxel magnetic resonance spectroscopy (MRS), following the latest MRSinMRS consensus group guidelines, was performed in the anterior cingulate cortex (ACC), left dorsolateral prefrontal cortex (DLPFC), and occipital cortex (OCC) to quantify differences in metabolite concentrations in individuals with chronic WAD with or without neuropathic pain (NP) components.Materials and methodsHealthy individuals (n = 29) and participants with chronic WAD (n = 29) were screened with the Douleur Neuropathique 4 Questionnaire (DN4) and divided into groups without (WAD-noNP, n = 15) or with NP components (WAD-NP, n = 14). Metabolites were quantified with LCModel following a single session in a 3 T MRI scanner within the ACC, DLPFC, and OCC.ResultsParticipants with WAD-NP presented moderate pain intensity and interference compared with the WAD-noNP group. Single-voxel MRS analysis demonstrated a higher glutamate concentration in the ACC and lower total choline (tCho) in the DLPFC in the WAD-NP versus WAD-noNP group, with no intergroup metabolite difference detected in the OCC. Best fit and stepwise multiple regression revealed that the normalised ACC glutamate/total creatine (tCr) (p = 0.01), DLPFC n-acetyl-aspartate (NAA)/tCr (p = 0.001), and DLPFC tCho/tCr levels (p = 0.02) predicted NP components in the WAD-NP group (ACC r2 = 0.26, α = 0.81; DLPFC r2 = 0.62, α = 0.98). The normalised Glu/tCr concentration was higher in the healthy than the WAD-noNP group within the ACC (p < 0.05), but not in the DLPFC or OCC. Neither sex nor age affected key normalised metabolite concentrations related to WAD-NP components when compared to the WAD-noNP group.DiscussionThis study demonstrates that elevated glutamate concentrations within the ACC are related to chronic WAD-NP components, while higher NAA and lower tCho metabolite levels suggest a role for increased neuronal–glial signalling and cell membrane dysfunction in individuals with chronic WAD-NP components

Virological and serological surveillance for type A influenza in the black-legged kittiwake (Rissa tridactyla)

<p>Abstract</p> <p>Background</p> <p>The epidemiology of avian influenza viruses (AIVs) in gulls is only partially known. The role of the world's most numerous gull species, the black-legged kittiwake (<it>Rissa tridactyla</it>), as a potential AIV reservoir species has been unclear. The prevalence of AIV and humoral response against AIV were therefore studied in a colony of apparently healthy black-legged kittiwakes breeding in a nesting cliff in the South West Barents Region of Norway (70°22' N, 31°10' E), in 2008 and 2009.</p> <p>Results</p> <p>AIVs were detected from the oropharynx and cloaca in low amounts, with prevalences of 15% and 5%, in 2008 and 2009, respectively. Direct, partial sequencing of the hemagglutinin (HA) gene revealed that the H4 subtype was present. In 2009, antibodies to influenza A virus were detected in sera from 57 of 80 adult birds. In contrast, none of the three-week-old chicks (n = 18) tested seropositive. Hemagglutination inhibition (HI) assays demonstrated that the adult kittiwakes primarily had antibodies specific to the gull-associated H13 and H16 subtypes, with antibodies to H16 being most common.</p> <p>Conclusions</p> <p>These results support that the highly pelagic black-legged kittiwake is a reservoir of AIV. The serological findings suggest that H16 might be the main AIV subtype in the black-legged kittiwake. Further studies are needed to understand the ecology of AIV in the black-legged kittiwake and in gulls in general.</p

Molecular analysis of the APC and MUTYH genes in Galician and Catalonian FAP families: a different spectrum of mutations?

<p>Abstract</p> <p>Background</p> <p>Familial adenomatous polyposis (FAP) is an autosomal dominant-inherited colorectal cancer syndrome, caused by germline mutations in the <it>APC </it>gene. Recently, biallelic mutations in <it>MUTYH </it>have also been identified in patients with multiple colorectal adenomas and in <it>APC</it>-negative patients with FAP. The aim of this work is therefore to determine the frequency of <it>APC </it>and <it>MUTYH </it>mutations among FAP families from two Spanish populations.</p> <p>Methods</p> <p>Eighty-two unrelated patients with classical or attenuated FAP were screened for <it>APC </it>germline mutations. <it>MUTYH </it>analysis was then conducted in those <it>APC</it>-negative families and in 9 additional patients from a previous study. Direct sequencing, SSCP analysis and TaqMan genotyping were used to identify point and frameshift mutations, meanwhile large rearrangements in the <it>APC </it>gene were screened by multiplex ligation-dependent probe amplification (MLPA).</p> <p>Results</p> <p><it>APC </it>germline mutations were found in 39% of the patients and, despite the great number of genetic variants described so far in this gene, seven new mutations were identified. The two hotspots at codons 1061 and 1309 of the <it>APC </it>gene accounted for 9,4% of the <it>APC</it>-positive families, although they were underrepresented in Galician samples. The deletion at codon 1061 was not found in 19 <it>APC</it>-positive Galician patients but represented 23% of the Catalonian positive families (p = 0,058). The same trend was observed at codon 1309, even though statistical analysis showed no significance between populations. Twenty-four percent of the <it>APC</it>-negative patients carried biallelic <it>MUTYH </it>germline mutations, and showed an attenuated polyposis phenotype generally without extracolonic manifestations. New genetic variants were found, as well as the two hotspots already reported (p.Tyr165Cys and p.Gly382Asp).</p> <p>Conclusion</p> <p>The results we present indicate that in Galician patients the frequency of the hotspot at codon 1061 in <it>APC </it>differs significantly from the Catalonian and also other Caucasian populations. Similar results had already been obtained in a previous study and could be due to the genetic isolation of the Galician population. <it>MUTYH </it>analysis is also recommended for all <it>APC</it>-negative families, even if a recessive inheritance is not confirmed.</p