The Returns to Flexible Postsecondary Education: The Effect of Delaying School

We investigate the returns to postsecondary education relaxing the standard assumption that it proceeds in a continuous manner. Using a unique survey that collects information on a representative cohort of graduates, we are able to estimate the effects of delaying school among successful graduates abstracting from specific macroeconomic conditions at the time of graduation. Our results show that graduates that delayed their education receive a premium relative to graduates that did not, even after considering other factors such as experience or labour market connections. These estimates are robust to the possibility of selection in the decision to return to school.Human Capital, Postsecondary Education, Flexible School Choice, School Delay

Unemployment insurance savings accounts in Latin America : overview and assessment

The unemployment protection systems that exist in most Latin American economies are generally considered inadequate in terms of providing insurance to workers and are prone to generate stratified labor markets. Recently, research effort and policy interest has turned to Unemployment Insurance Savings Accounts (UISAs) as an alternative to traditional systems of unemployment insurance. UISAs are schemes of individual mandatory savings that smooth income over an individual's life cycle time rather than pooling unemployment risk over the total working population at a point in time. Although this form of unemployment insurance diminishes the moral hazard problems associated with traditional insurance methods, it presents problems of its own. First, it is questionable that these systems provide adequate protectionagainst unemployment risk. Additionally, their effects on the promotion of informal labor markets and their administrative costs are yet to be determined. Finally, the effectiveness as a form of unemployment insurance depends critically upon the performance and credibility of the financial institutions managing the funds. This paper examines the experience of Latin American countries that use UISAs, with the hope of highlighting the problems of the system and identifying areas for future theoretical and empirical work. In conclusion, the overall effect of UISAs depends on a vast array of specific country characteristics and program parameters. The way the system is implemented, existing labor regulation, the extent of the informal economy and the scope for collusive behavior greatly influence the success of these programs. This calls for a more extensive research effort in the area.Labor Markets,,Labor Policies,Access to Finance,Banks&Banking Reform

The fertility of recent immigrants to Canada

In this paper we examine the fertility experience of immigrants during their first years in Canada. Fertility decisions at the time of arrival may be crucial in determining immigrants' economic assimilation into the new country, as households with infants usually face large expenses and are constrained in the amount of time they can supply to the labour market. Using the confidential files of the Canadian Census of Population for the years 1991 through 2006 we look at native born-immigrant differentials in new births up to five years after migration. We find evidence of a relatively rapid growth in births during this initial period compared to both similar natives and migrants themselves during the two years before the move. To what extent the presence of infants in immigrant households converges to the levels of the native-born during the early migration years differs greatly by broad area of origin

Educational Attainment and Labor Market Performance: An Analysis of Immigrants in France

Using a recent survey of immigrants to France, we provide a detailed analysis of the educational attainment and labor market performance of various sub-population groups in France. Our results indicate that immigrants to France are less educated than the native born and that these differences can be tracked down to differences in socioeconomic background for most groups of immigrants. Similarly, there is a significant wage gap between immigrant and native-born workers, but this is reduced and sometimes disappears after correcting for selection into employment. In most cases the remaining differences in education and labor market outcomes seem related to the area of origin of the immigrant as well as where the education of the immigrant is obtained

Evidence from Canada contradicts the common notion that migrant women are secondary workers

It is a common assumption that most migrant women only enter the workforce as so-called ‘secondary workers’, supplementing the income of their husbands for a relatively short amount of time. Using data from more than 800,000 women in Canada from 1991 to 2006, Alícia Adserà and Ana Ferrer find that in their workforce participation, married women immigrants tend to fit the profile of married native women and that they experience rising wages and an increase in the amount of analytical skills needed for their work over time. They write while immigrant women experience barriers to entry into skilled occupations, these too ease over time, though not to full wage parity with native women

Research Brief No. 16 - The Effects of Age and Background on the Fertility Patterns of Child Migrants

This paper challenges the common notion that immigrants have more children than the native-born population. More specifically, immigrants who arrived in Canada, England or France at an early age have about the same number of children as the native-born. By examining child immigrants, the paper is able to attribute this finding to the hypothesis that, with time, immigrants adopt the destination country’s norms. The results also show that the relationship between age at migration and number of children differs for immigrants from certain countries. Likewise, the fertility patterns of child migrants also depend on their destination country

Peptide-Phospholipid Cross-Linking Reactions: Identification of Leucine Enkephalin-Alka(e)nal-Glycerophosphatidylcholine Adducts by Tandem Mass Spectrometry

The covalent interactions between peptides and lipid oxidation products, with formation of Schiff and Michael adducts, are known to occur during free radical oxidative damage. In this study, leucine-enkephalin-glycerophosphatidylcholine alka(e)nal adducts were analyzed by electrospray tandem mass spectrometry (MS/MS). Upon collision-induced dissociation of the Leucine enkephalin-2-(9-oxo-nonanoyl)-1-palmitoyl-3-glycerophosphatidylcholine, an alkanal Schiff adduct observed at m/z 1187.7, the main product ions were attributed to the phosphocholine polar head and loss of the peptide. Also, product ions resulting from characteristic losses of phosphatidylcholines and cleavages of the peptide chain (mainly b-type) were observed. Additional product ions formed by combined peptide and phosphatidylcholine fragmentations were identified. The fragmentation pattern of the leucine enkephalin-alkanal Schiff adduct and the leucine enkephalin-alkenal phosphatidylcholine Schiff and Michael adducts were similar, although the loss of the peptide for the Michael adduct should occur through a distinct mechanism. These fragmentation pathways differ greatly from those described for peptide-lipid Schiff and Michael adducts, in which only peptide chain cleavages are reported, probably due to charge retention in the glycerophosphatidylcholine polar head in peptide-glycerophosphatidylcholine adducts

Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles with potential application in dental tissue engineering

"This is an Accepted Manuscript of an article published by Taylor & Francis inInternational Journal of Polymeric Materials and Polymeric Biomaterials on AUG 08 2020, available online: https://www.tandfonline.com/doi/full/10.1080/00914037.2019.1616197"[EN] Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles were synthesized to explore their potential use in the biomedical field. The nanoparticles were two distinct polyhedral oligomeric silsesquioxanes (POSS), both used at 5% wt/wt concentration, specifically methacrylisobutyl POSS and methacryl POSS. These materials were investigated for their possible application as coatings as well as with regenerative purposes in dental engineering, and their viability for this application was assessed. Thus, pure PGS and nanohybrids thereof were obtained as scaffolds (that is, porous structures, designed with regenerative purposes) and as films (intended for coatings and to be used as controls).The authors acknowledge Dr. Kirsten Techmer from Geoscience Center of the Georg-August-University Gottingen for performing the EDX-SEM analysis, the assistance and advice of the Julich Center for Neutron Science (JCNS) and Institute for Complex Systems (ICS), Forschungszentrum Julich GmbH (Germany), and the Electron Microscopy Service of the Universitat Politecnica de Valencia (Spain). This work was partially funded by the Spanish Ministerio de Economía y Competitividad through DPI2015-65401-C3-2-R project and by the German Research Foundation [DFG/MWK INST 1525/39-1 FUGG]. A.V.-Ll. acknowledges the support of the Generalitat Valenciana, Conselleria de Educación, Investigación, Cultura y Deporte through project AEST/2018/014.Tallá Ferrer, C.; Vilariño, G.; Rizk, M.; Sydow, H.; Vallés Lluch, A. (2020). Nanocomposites based on poly(glycerol sebacate) with silica nanoparticles with potential application in dental tissue engineering. International Journal of Polymeric Materials. 69(12):761-772. https://doi.org/10.1080/00914037.2019.1616197S7617726912Wang, Y., Ameer, G. A., Sheppard, B. J., & Langer, R. (2002). A tough biodegradable elastomer. Nature Biotechnology, 20(6), 602-606. doi:10.1038/nbt0602-602Loh, X. J., Abdul Karim, A., & Owh, C. (2015). Poly(glycerol sebacate) biomaterial: synthesis and biomedical applications. Journal of Materials Chemistry B, 3(39), 7641-7652. doi:10.1039/c5tb01048aRai, R., Tallawi, M., Grigore, A., & Boccaccini, A. R. (2012). Synthesis, properties and biomedical applications of poly(glycerol sebacate) (PGS): A review. 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A relaxation technique enhances psychological well-being and immune parameters in elderly people from a nursing home: A randomized controlled study

Background: The aging process involves a decline in immune functioning that renders elderly people more vulnerable to disease. In residential programs for the aged, it is vital to diminish their risk of disease, promote their independence, and augment their psychological well-being and quality of life. Methods: We performed a randomized controlled study, evaluating the ability of a relaxation technique based on Benson’s relaxation response to enhance psychological well-being and modulate the immune parameters of elderly people living in a geriatric residence when compared to a waitlist control group. The study included a 2-week intervention period and a 3-month follow-up period. The main outcome variables were psychological well-being and quality of life, biomedical variables, immune changes from the pre-treatment to post-treatment and follow-up periods. Results: Our findings reveal significant differences between the experimental and control groups in CD19, CD71, CD97, CD134, and CD137 lymphocyte subpopulations at the end of treatment. Furthermore, there was a decrease in negative affect, psychological discomfort, and symptom perception in the treatment group, which increased participants’ quality of life scores at the three-month follow-up. Conclusions: This study represents a first approach to the application of a passive relaxation technique in residential programs for the elderly. The method appears to be effective in enhancing psychological well-being and modulating immune activity in a group of elderly people. This relaxation technique could be considered an option for achieving health benefits with a low cost for residential programs, but further studies using this technique in larger samples of older people are needed to confirm the trends observed in the present study. Trial registration: International Standard Randomised Controlled Trial Number Register ISRCTN85410212

Eficiência energética na fabricação de placas cerãmicas mediante a utilização de óleo térmico

O processo de fabricação de placas cerâmicas consome uma grande quantidade de energia, maioritariamente energia térmica, que se obtém da combustão de gás natural. O aumento do custo deste combustível, assim como a situação económica do presente, faz com que este custo seja crítico para as empresas e pode minar a sua competitividade. O processo de cozedura das placas cerâmicas em fornos de rolos não se destaca precisamente pelo aproveitamento da energia utilizada, visto que aproximadamente 50% perdese através das chaminés de fumos e de arrefecimento do forno. Com o propósito de melhorar o aproveitamento da energia consumida durante a operação de cozedura instalaramse, nas chaminés de um forno, dois permutadores de calor, nos quais os gases provenientes do forno cedem o seu calor sensível a um óleo térmico, que posteriormente o transfere, através de outros dois permutadores, aos gases de secagem nas condutas de recirculação de um secador vertical. Neste trabalho apresenta-se uma instalação industrial experimental, na qual os resultados obtidos de economia energética se situam num valor médio de 650 kW, dependendo das condições de funcionamento e dos materiais processados