5,535 research outputs found

    Migration, Social Security, and Economic Growth

    Get PDF
    This paper studies the effect of population aging on economic performance in an overlapping-generations model with international migration. Fertility is endogenized so that immigrants and natives can have different fertility rates. Fertility is an important determinant to the tax burden of social security since it affects the quantity and quality of future tax payers. We find that introducing immigrants into the economy can reduce the tax burden of social security. If life expectancy (or the replacement ratio) is high enough, the growth rate of GDP per worker for an economy with international migration will be higher than for a closed economy. Regarding migration policies, our numerical results indicate that economic growth rate of GDP per worker will first decrease then increase as the flow of immigrants increases. Increasing the quality of immigrants will enhance economic growth.Economic growth; Fertility; Migration; Social security.

    Distribution specificities of long-period comets' perihelia. Hypothesis of the large planetary body on the periphery of the Solar System

    Full text link
    The present paper reviews selected aspects of the Guliyev's hypothesis about the massive celestial body at a distance of 250-400 AU from the Sun as well as the factor of comets transfer. It is shown, that the conjecture of the point around which cometary perihelia might be concentrated, is not consistent. On the issue of perihelia distribution, priority should be given to the assumption that there is a plane or planes around which the concentration takes place. A total of 24 comet groups were investigated. In almost all cases there are detected two types of planes or zones: the first one is very close to the ecliptic, another one is about perpendicular to it and has the parameters: ip = 86{\deg}, {\Omega}p = 271.7{\deg}. The existence of the first area appears to be related to the influence of giant planets. The Guliyev's hypothesis says that there is a massive perturber in the second zone, at a distance of 250-400 AU. It shows that number of aphelia and distant nodes of cometary orbits in this interval significantly exceeds the expected background. Analysis of the angular parameters of the comets, calculated relative to the second plane (reference point is the ascending node of a large circle) displays clear patterns: shortage of comets near i' = 180{\deg}, excess of them near B'= 0{\deg} (ecliptic latitude of perihelion) and shortage near B'=-90{\deg}. The analysis also shows irregularity of distant nodes, overpopulation of perihelion longitudes in the range 350{\deg}-20{\deg}. Plotted distributions of aphelia N(Q) and distant cometary nodes clearly indicate a perturbation of the natural course near 300 AU. On the basis of collected cometary data, we have estimated orbital elements of the hypothetical planetary body: a = 337 AU; e = 0.14; {\omega} = 57{\deg}; {\Omega} = 272.7{\deg}; i = 86{\deg}

    Migration, Social Security, and Economic Growth

    Get PDF
    This paper studies the effect of population aging on economic performance in an overlapping-generations model with international migration. Fertility is endogenized so that immigrants and natives can have different fertility rates. Fertility is an important determinant to the tax burden of social security since it affects the quantity and quality of future tax payers. We find that introducing immigrants into the economy can reduce the tax burden of social security. If life expectancy (or the replacement ratio) is high enough, the growth rate of GDP per worker for an economy with international migration will be higher than for a closed economy. Regarding migration policies, our numerical results indicate that economic growth rate of GDP per worker will first decrease then increase as the flow of immigrants increases. Increasing the quality of immigrants will enhance economic growth

    Comparative study of an externship program versus a corporate-academic cooperation program for enhancing nursing competence of graduating students

    Get PDF
    BACKGROUND: New graduates report intense stress during the transition from school to their first work settings. Managing this transition is important to reduce turnover rates. This study compared the effects of an externship program and a corporate-academic cooperation program on enhancing junior college students’ nursing competence and retention rates in the first 3 months and 1 year of initial employment. METHODS: This two-phase study adopted a pretest and posttest quasi-experimental design. All participants were graduating students drawn from a 5-year junior nursing college in Taiwan. There were 19 and 24 students who participated in the phase I externship program and phase II corporate-academic cooperation program, respectively. The nursing competence of the students had to be evaluated by mentors within 48 hours of practicum training and after practicum training. The retention rate was also surveyed at 3 months and 1 year after beginning employment. RESULTS: Students who participated in the corporate-academic cooperation program achieved a statistically significant improvement in nursing competence and retention rates relative to those who participated in the externship program (p < 0.01 and p < 0.05, respectively). CONCLUSIONS: The corporate-academic cooperation program facilitates the transition of junior college nursing students into independent staff nurses, enhances their nursing competence, and boosts retention rates

    Association of erythrocyte n-3 polyunsaturated fatty acids with incident type 2 diabetes in a Chinese population

    Get PDF
    Summary Background & aims The association between circulating n-3 polyunsaturated fatty acid (PUFA) biomarkers and incident type 2 diabetes in Asian populations remains unclear. We aimed to examine the association of erythrocyte n-3 PUFA with incident type 2 diabetes in a Chinese population. Methods A total of 2671 participants, aged 40–75 y, free of type 2 diabetes at baseline, were included in the present analysis. Incident type 2 diabetes cases (n = 213) were ascertained during median follow-up of 5.6 years. Baseline erythrocyte fatty acids were measured by gas chromatography. We used multivariable Cox regression models to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) of type 2 diabetes across quartiles of erythrocyte n-3 PUFA. Results After adjustment for potential confounders, HRs (95% CIs) of type 2 diabetes were 0.68 (0.47, 1.00), 0.77 (0.52, 1.15), and 0.63 (0.41, 0.95) in quartiles 2–4 of docosapentaenoic acid (C22:5n-3) (P-trend = 0.07), compared with quartile 1; and 1.08 (0.74, 1.60), 1.03 (0.70, 1.51), and 0.57 (0.38, 0.86) for eicosapentaenoic acid (C20:5n-3) (P-trend = 0.007). No association was found for docosahexaenoic acid (C22:6n-3) or alpha-linolenic acid (C18:3n-3). Conclusions Erythrocyte n-3 PUFA from marine sources (C22:5n-3 and C20:5n-3), as biomarkers of dietary marine n-3 PUFA, were inversely associated with incident type 2 diabetes in this Chinese population. Future prospective investigations in other Asian populations are necessary to confirm our findings
    • …
    corecore