Baby-boom, baby-bust and the Great Depression

The baby-boom and subsequent baby-bust have shaped much of the history of the second half of the 20th century; yet it is still largely unclear what caused them. This paper presents a new unified explanation of the fertility Boom-Bust that links the latter to the Great Depression and the subsequent economic recovery. We show that the 1929 Crash attracted young married women 20 to 34 years old in 1930 (whom we name D-cohort) in the labor market possibly via an added worker effect. Using several years of Census micro data, we further document that the same cohort kept entering into the market in the 1940s and 1950s as economic conditions improved, decreasing wages and reducing work incentives for younger women. Its retirement in the late 1950s and in the 1960s instead freed positions and created employment opportunities. Finally, we show that the entry of the D-cohort is associated with increased births in the 1950s, while its retirement turned the fertility Boom into a Bust in the 1960s. The work behavior of this cohort explains a large share of the changes in both yearly births and completed fertility of all cohorts involved.

Understanding Recent Developments in the Turkish Labor Market: Empirical Essays with a Gender Focus

This dissertation comprises three essays on the Turkish labor market. The first essay characterizes the distinctive characteristics of the Turkish labor market with the aim of understanding the factors lying behind its long-standing poor performance relative to its European counterparts. The analysis is based on a cross-country comparison among selected European Union countries. Among all the indicators of labor market flexibility, non-wage cost rigidities are regarded as one of the most important factors in slowing down employment creation in Turkey. The second essay focuses on an employment subsidy policy which introduces a reduction in non-wage costs through social security premium incentives granted to women and young men. Exploiting a difference-in-difference-in differences strategy, I evaluate the effectiveness of this policy in creating employment for the target group. The results, net of the recent crisis effect, suggest that the policy accounts for a 1.4% to 1.6% increase in the probability of being hired for women aged 30 to 34 above men of the same age group in the periods shortly after the announcement of the policy. In the third essay of the dissertation, I analyze the labor supply response of married women to their husbands' job losses (AWE). I empirically test the hypothesis of added worker effect for the global economic crisis of 2008 by relying on the Turkey context. Identification is achieved by exploiting the exogenous variation in the output of male-dominated sectors hard-hit by the crisis and the gender-segmentation that characterizes the Turkish labor market. Findings based on the instrumental variable approach suggest that the added worker effect explains up to 64% of the observed increase in female labor force participation in Turkey. The size of the effect depends on how long it takes for wives to adjust their labor supply to their husbands' job losses.

Female employment from the household. Towards a comprehensive analysis of work-life articulation

Research on women’s employment has proliferated over recent decades, often under a perspective that conceptualizes female labour market activity as independent of male presences and absences in the productive and reproductive spheres. In the face of these approaches, the article argues the need to focus on the couple as the unit of analysis of work-life articulation. After referring to the main theoretical arguments that, from a gender perspective within labour studies, have pointed out the relevance of placing the household as the central space for the analysis of the sexual division of labour, the article reviews different empirical contributions that have incorporated such perspective in the international literature. Next, the state of the art in the Spanish literature is presented, before arguing the desirability of applying such framework of analysis to the study of employment and care work in Spanish households, which are at present undergoing major transformations.

Saúde e capacidade para o trabalho de eletricitários do Estado de São Paulo

Apesar dos elevados riscos à saúde e capacidade para o trabalho dos eletricitários, há carência de estudos sobre o tema no Brasil. O objetivo desse estudo é identificar o perfil de saúde e capacidade para o trabalho de eletricitários de São Paulo. Foi feito um estudo transversal junto a 475 trabalhadores de uma empresa do setor eletricitário. A coleta de dados foi por meio de questionários sobre capacidade para o trabalho, estado de saúde, estresse no trabalho, atividade física, dependência ao tabaco e ao álcool. A consistência interna das escalas foi avaliada usando o coeficiente alfa de Cronbach. Foi feita análise descritiva por meio das médias, desvios-padrão, valores mínimos e máximos dos escores e proporções para as variáveis qualitativas. O estado de saúde dos trabalhadores apresentou pontuação elevada nas dimensões analisadas, com médias entre 72,8 a 91,2 (escore de 0,0 a 100,0 pontos). A capacidade para o trabalho teve pontuação elevada, com média de 41,8 (escore de 7,0 a 49,0 pontos). Concluiu-se que os trabalhadores da população de estudo apresentaram elevados padrões do estado de saúde e da capacidade para o trabalho. Sugere-se o desenvolvimento de estudos longitudinais para avaliar relações causais e a existência de efeito do trabalhador sadio.

Compatible Ternary Blends of Chitosan/poly(vinyl alcohol)/poly(lactic acid) Produced by Oil-in-Water Emulsion Processing

Ternary compatible blends of chitosan, poly(vinyl alcohol), and poly(lactic acid) were prepared by an oil-in-water (O/W) emulsion process. Solutions of chitosan in aqueous acetic acid, poly(vinyl alcohol) (PVA) in water, and poly(lactic acid) (PLA) in chloroform were blended with a high shear mixer. PVA was used as an emulsifier to stabilize the emulsion and to reduce the interfacial tension between the solid polymers in the blends-produced. It proved to work very well because the emulsions were stable for periods of days or weeks and compatible blends were obtained When PVA was added. This effect was attributed to a synergistic effect of PVA and chitosan because the binary blends PVA/PLA and chitosan/PLA were completely incompatible; The blends were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal mechanical analysis (TMA), stress strain tests, and Fourier transform infrared spectroscopy (FTIR). The results indicated that despite the fact that the system contained distinct phases some degree of molecular miscibility occurred when the three components were present in the blend.

Razões de mortalidade frente ao efeito desigualdade em estudos de mortalidade associada a categorias ocupacionais e níveis sociais

As razões de mortalidade: "Standardized Risk Ratio" (SRR), "Standardized Mortality Ratio" (SMR) e "Standardized Proportional Mortality Ratio" (SPMR) são apresentadas visando divulgar uma metodologia para o estudo da mortalidade associada a categorias ocupacionais e níveis sociais. Discute-se a influência do "Healthy Worker Effect" e do Efeito Desigualdade na escolha da população de referência e apresenta-se uma forma operacional de testar a significância estatística dessas razões.

Symptoms of chronic stress at work in NGO workers

Working in a NGO often involves providing life saving resources (food, medicine, equipment, water, etc) to needy populations around the globe. Such duty requires highly dedicated employees and humanitarian workers are said to face a hign degree of pressure in their daily work. Despite the evidence of taxing work demands, and a high potential for stress related problems, very few studies on occupational chronic stress have specifically looked at NGO workers. Assuming that "field stress" can relay to workers at headquarters, we carried out an exploratory study about occupational health among employees of a NGO's headquarters. We sent a questionnaire to all employees (N=130) of a NGO headquarters located in Switzerland. We used the TST questionnaire (French version of the Langner's questionnaire on psychiatric symptoms) to identify cases with potential mental health problems. We also included in the questionnaire some items about motivation, acknowledgment, work-life balance, job demand, and autonomy. A total of 75 employees answered our questionnaire (57% response rate). 44% of our sample were men (n=33) and 56% were women (n=42). The mean age was of 40 years (SD=7.6). 56% were working at the headquarters of the NGO in questions as of 2 years or less. Not surprisingly, a majority of respondents reported to be highly motivated (74%) and the meaning of work was important for 80% of them. However, 35% indicated having problems in conciliating their private and professional life. Most frequent reported symptoms included feeling "weak all over" (81%), having "trouble getting asleep often" (35%), "clogging in nose" (35%), feeling "nervous often" (33%), and "memory not all right" (33%). The score for psychiatric symptoms was high in 8 (11%) employees whose health might therefore be at risk. In comparison, other sudies showed that this proportion was 9% for French teachers and 16% for sales personnel1. Results show that symptoms of mental health problems do occur among NGO workers. Some of these symptoms are known to be linked to occupational stress. Chronic stress manifests itself first in non-specific symptoms (e.g. fatigue) and later in specific pathologies. This could explain the relatively low proportion of cases with a high score in Langner's scale than was expected. Therefore, we hypothesize a healthy worker effect. The fact that our sample is 40 years old in average, and that the turnover is quite high can also support this hypothesis. Further research is needed in order to better understand occupational stress in this specific population. An upcoming study will investigate the role of organizational factors associated with health complaints. Therefore, a longitudinal survey including quantitative and qualitative methods is appropriate.

What does the National High School Exam (enem) tell Brazilian society?

This article assesses the limitations and potentials of the National High School Exam (ENEM) as an indicator of school effectiveness in Brazil, and considers the effects of introducing contextual variables. A multilevel regression analysis was performed on three levels (individual, school and state) using microdata on 17,359 schools from 2009 and 2010. Contextual factors made it possible to explain 79% of the difference between schools. The raw average and value-added (random effect at the school level) produced contrasting evaluations in 34% of cases; and the average was more stable (r = 0.8) than value-added (r = 0.5) in both years. Various shortcomings in the ENEM as an indicator of school effectiveness were identified. The results show that this league table reveals more about socioeconomic conditions than the schools' own merit, in other words the value-added they are supposedly providing to the students.

A multiplicative model for standardizing vital rates without using external standards

Standardization is a common method for adjusting confounding factors when comparing two or more exposure category to assess excess risk. Arbitrary choice of standard population in standardization introduces selection bias due to healthy worker effect. Small sample in specific groups also poses problems in estimating relative risk and the statistical significance is problematic. As an alternative, statistical models were proposed to overcome such limitations and find adjusted rates. In this dissertation, a multiplicative model is considered to address the issues related to standardized index namely: Standardized Mortality Ratio (SMR) and Comparative Mortality Factor (CMF). The model provides an alternative to conventional standardized technique. Maximum likelihood estimates of parameters of the model are used to construct an index similar to the SMR for estimating relative risk of exposure groups under comparison. Parametric Bootstrap resampling method is used to evaluate the goodness of fit of the model, behavior of estimated parameters and variability in relative risk on generated sample. The model provides an alternative to both direct and indirect standardization method. ^

Nuclear magnetic resonance studies of molecular interactions and structures

This thesis is concerned with the investigation, by nuclear magnetic resonance spectroscopy, of the molecular interactions occurring in mixtures of benzene and cyclohexane to which either chloroform or deutero-chloroform has been added. The effect of the added polar molecule on the liquid structure has been studied using spin-lattice relaxation time, 1H chemical shift, and nuclear Overhauser effect measurements. The main purpose of the work has been to validate a model for molecular interaction involving local ordering of benzene around chloroform. A chemical method for removing dissolved oxygen from samples has been developed to encompass a number of types of sample, including quantitative mixtures, and its supremacy over conventional deoxygenation technique is shown. A set of spectrometer conditions, the use of which produces the minimal variation in peak height in the steady state, is presented. To separate the general diluting effects of deutero-chloroform from its effects due to the production of local order a series of mixtures involving carbon tetrachloride, instead of deutero-chloroform, have been used as non-interacting references. The effect of molecular interaction is shown to be explainable using a solvation model, whilst an approach involving 1:1 complex formation is shown not to account for the observations. It is calculated that each solvation shell, based on deutero-chloroform, contains about twelve molecules of benzene or cyclohexane. The equations produced to account for the T1 variations have been adapted to account for the 1H chemical shift variations in the same system. The shift measurements are shown to substantiate the solvent cage model with a cage capacity of twelve molecules around each chloroform molecule. Nuclear Overhauser effect data have been analysed quantitatively in a manner consistent with the solvation model. The results show that discrete shells only exist when the mole fraction of deutero-chloroform is below about 0.08.

Penetration of hydrolysed soy protein-added brine and its effect on yield and pH of beef steaks from the biceps femoris muscle

This study was aimed to evaluate the penetration behaviour of different brines with tumbled beef steaks from the biceps femoris muscle, specifically their interactions with pH and effects on yield. Six muscles from different animals, divided into origin (OP) and insertion (IP) portions, were cut into 60 steaks of 2.5 cm thickness and tumbled for 30 or 60 min. The steaks were tumbled with two brines, with (WTB/HSP) or without (WTB) hydrolysed soy protein (HSP), and steaks that were not tumbled with brine or water were used as controls. Brine penetration was verified by measuring the amount of dye-containing brine (absorbance at 627 nm) recovered from homogenates of four thin (2 mm) slices from the surface of the beef steaks after tumbling. The WTB/HSP steaks exhibited greater (P < 0.05) brine penetration when tumbled for 60 min than for 30 min. The OP steaks showed greater yield and lower pH (P < 0.05) than IP steaks. HSP-added brine increased the water absorption and retention in the first slices of the steaks, and its efficiency was increased with a longer tumbling time. The portion of the biceps femoris muscle used influenced brine absorption and retention, impacting meat yield. (C) 2010 Elsevier Ltd. All rights reserved.

Effect of added dead space on sleep disordered breathing at high altitude.

OBJECTIVE: Sleep disordered breathing with central apnea or hypopnea frequently occurs at high altitude and is thought to be caused by a decrease in blood CO(2) level. The aim of this study was to assess the effects of added respiratory dead space on sleep disordered breathing.¦METHODS: Full polysomnographies were performed on 12 unacclimatized swiss mountaineers (11 males, 1 female, mean age 39±12 y.o.) in Leh, Ladakh (3500m). In random order, half of the night was spent with a 500ml increase in dead space through a custom designed full face mask and the other half without it.¦RESULTS: Baseline data revealed two clearly distinct groups: one with severe sleep disordered breathing (n=5, AHI>30) and the other with moderate to no disordered breathing (n=7, AHI<30). DS markedly improved breathing in the first group (baseline vs DS): apnea hypopnea index (AHI) 70.3±25.8 vs 29.4±6.9 (p=0.013), oxygen desaturation index (ODI): 72.9±24.1/h vs 42.5±14.4 (p=0.031), whereas it had no significant effect in the second group or in the total population. Respiratory events were almost exclusively central apnea or hypopnea. Microarousal index, sleep efficiency, and sleep architecture remained unchanged with DS. A minor increase in mean PtcCO(2) (n=3) was observed with DS.¦CONCLUSION: A 500ml increase in dead space through a fitted mask may improve nocturnal breathing in mountaineers with severe altitude-induced sleep disordered breathing.

Thermogenesis in obese women: effect of fructose vs. glucose added to a meal.

To assess the effect of a fructose meal on resting energy expenditure (EE), indirect calorimetry was used in 23 women (10 lean and 13 obese) for 30 min before and 6 h after the ingestion of a mixed meal containing 20% protein, 33% fat, and either 75 g glucose or 75 g fructose as carbohydrate source (47%). Expressed as a percentage of the energy content of the meal, the thermogenic response to the fructose meal was significantly greater (10.2 +/- 0.5%) than that of the glucose meal (8.4 +/- 0.4%, P less than 0.01). This difference was still apparent when the lean and obese women were considered separately. The mean respiratory quotient during the 6-h postprandial period was significantly greater (P less than 0.01) for the fructose (0.85 +/- 0.01) than for the glucose meal (0.83 +/- 0.01) in the combined subjects. In addition, cumulative carbohydrate oxidation was significantly greater after the fructose than after the glucose meal (51.1 +/- 2.3 vs. 40.9 +/- 2.0 g/6 h, respectively, P less than 0.01). Only small changes were observed in postprandial plasma levels of glucose and insulin after the fructose meal, but the plasma levels of lactate increased more with fructose than with the glucose meal. These results suggest that there might be some advantages (higher thermogenesis and carbohydrate oxidations) in using fructose as part of the carbohydrate source in diet of people with obesity and/or insulin resistance.

Morphological alterations induced by boric acid and fipronil in the midgut of worker honeybee (Apis mellifera L.) larvae

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of topical application of juvenile hormone (JH) in honeybee worker larvae on the development of the Dufour's and Koschewnikow's glands

In order to investigate the action of the juvenile hormone (JH) on honeybee caste differentiation two exocrine glands, Koschewnikow and Dufour glands, were chosen for study. Two combs (I & II) were taken from a single posture of a queen to use for this research. In comb I the larvae were treated with a topical application of JH in Acetone, and those from the comb II (control group) received only Acetone. Immediately after the emergence of the workers, their glands were dissected and prepared for microscopic measurements. The results showed cell area reduction in the Koschewnikow gland induced by the JH application. The results for the Dufour gland displayed taller epithelial cells with the JH application. The difference in glandular responses to the JH relates to gland function, hormone targets, and individual homeostasis.