40 research outputs found
Labour market effects of unemployment accounts: insights from behavioural economics
This paper reconsiders the behavioural effects of replacing the existing unemployment insurance system with unemployment accounts (UAs). Under this alternative system, workers are required to save a fraction of their wage in special accounts whereas the unemployed are allowed to withdraw savings from these accounts. Previous studies argued that such a reform will improve employment incentives considerably and thereby lead to a dramatic decrease in unemployment levels and durations. We show that this expected impact hinges critically on the assumptions on intertemporal choice. Using recent insights from behavioural economics, we demonstrate that the theoretical impact of UAs on unemployment is limited. This study points out that the overall effect of introducing an UA system on labour market behaviour is ambiguous rather than substantially positive.unemployment insurance; unemployment accounts; time preferences; behavioural economics
Risk aversion and job mobility
Job mobility is inherently risky as workers have limited ex ante information about the quality of outside jobs. Using a large longitudinal Dutch dataset, which includes data on risk preferences elicited through an (incentivized) lottery-choice experiment, we examine the relation between risk aversion and job mobility. The evidence shows that risk averse workers are less likely to move to other jobs. The results are stronger for male workers and for workers who hold a permanent contract. Our empirical findings indicate that the negative relation between risk aversion and job mobility is driven by the job acceptance rather than the search effort decision
Teacher bias or measurement error?
In many countries, teachers' track recommendations are used to allocate
students to secondary school tracks. Previous studies have shown that students
from families with low socioeconomic status (SES) receive lower track
recommendations than their peers from high SES families, conditional on
standardized test scores. It is often argued that this indicates teacher bias.
However, this claim is invalid in the presence of measurement error in test
scores. We discuss how measurement error in test scores generates a biased
coefficient of the conditional SES gap, and consider three empirical strategies
to address this bias. Using administrative data from the Netherlands, we find
that measurement error explains 35 to 43% of the conditional SES gap in track
recommendations
Is Social Inequality in School-Age Achievement Generated before or during Schooling? A European Perspective
Social gaps in children’s educational achievement emerge early in life and remain stable over schooling. Does social origin constantly shape achievement or is social inequality in school just an echo of inequality settled before schooling? We extend the previous research by studying the origins of social gaps in language achievement among primary-school students in Germany, the Netherlands, and the United Kingdom. Based on dynamic accounts of skill development, we expected social origin to shape school-age achievement not only directly but also indirectly via before-school achievement. Using longitudinal data (Cohort Study on Educational Careers, Millennium Cohort Study, and National Educational Panel Study) and applying an instrumental variable approach, we estimated the extent to which achievement gaps by parental education in school were generated before and during schooling. About 50–80 per cent of language gaps observed at end of primary school were explained by gaps settled before formal schooling in all three countries. Conversely, at most 20–50 per cent of school-age gaps were generated during schooling. These findings suggest that the roots of social inequality in school-age achievement must be sought primarily in processes transpiring before school life starts
Do more hours in center-based care cause more externalizing problems? A cross-national replication study
Whether high quantities of center-based care cause behavior problems is a controversial question. Studies using covariate adjustment for selection factors have detected relations between center care and behavior problems, but studies with stronger internal validity less often find such evidence. We examined whether within-child changes in hours in center-based care predicted changes in externalizing problems in toddlers and preschoolers (N = 10,105; 49% female; data collection 1993–2012) in seven studies, including from Germany, Netherlands, Norway, two from Canada and two from the U.S. Race/ethnicity data were only collected in the United States (57% and 80% White; 42% and 13% African-American; 1.2% and 5% Latinx). Meta-analyses showed no association (r = .00, p = .88) between hours in center-based care and externalizing problems
Dried blood spot UHPLC-MS/MS analysis of oseltamivir and oseltamivircarboxylate—a validated assay for the clinic
The neuraminidase inhibitor oseltamivir (Tamiflu®) is currently the first-line therapy for patients with influenza virus infection. Common analysis of the prodrug and its active metabolite oseltamivircarboxylate is determined via extraction from plasma. Compared with these assays, dried blood spot (DBS) analysis provides several advantages, including a minimum sample volume required for the measurement of drugs in whole blood. Samples can easily be obtained via a simple, non-invasive finger or heel prick. Mainly, these characteristics make DBS an ideal tool for pediatrics and to measure multiple time points such as those needed in therapeutic drug monitoring or pharmacokinetic studies. Additionally, DBS sample preparation, stability, and storage are usually most convenient. In the present work, we developed and fully validated a DBS assay for the simultaneous determination of oseltamivir and oseltamivircarboxylate concentrations in human whole blood. We demonstrate the simplicity of DBS sample preparation, and a fast, accurate and reproducible analysis using ultra high-performance liquid chromatography coupled to a triple quadrupole mass spectrometer. A thorough validation on the basis of the most recent FDA guidelines for bioanalytical method validation showed that the method is selective, precise, and accurate (≤15% RSD), and sensitive over the relevant clinical range of 5–1,500 ng/mL for oseltamivir and 20–1,500 ng/mL for the oseltamivircarboxylate metabolite. As a proof of concept, oseltamivir and oseltamivircarboxylate levels were determined in DBS obtained from healthy volunteers who received a single oral dose of Tamiflu®
Expression of gibberellin 20-oxidase1 (AtGA20ox1) in Arabidopsis seedlings with altered auxin status is regulated at multiple levels
Bioactive gibberellins (GAs) affect many biological processes including germination, stem growth, transition to flowering, and fruit development. The location, timing, and level of bioactive GA are finely tuned to ensure that optimal growth and development occur. The balance between GA biosynthesis and deactivation is controlled by external factors such as light and by internal factors that include auxin. The role of auxin transport inhibitors (ATIs) and auxins on GA homeostasis in intact light-grown Arabidopsis thaliana (L.) Heynh. seedlings was investigated. Two ATIs, 1-N-naphthylthalamic acid (NPA) and 1-naphthoxyacetic acid (NOA) caused elevated expression of the GA biosynthetic enzyme AtGA20-oxidase1 (AtGA20ox1) in shoot but not in root tissues, and only at certain developmental stages. It was investigated whether enhanced AtGA20ox1 gene expression was a consequence of altered flow through the GA biosynthetic pathway, or was due to impaired GA signalling that can lead to enhanced AtGA20ox1 expression and accumulation of a DELLA protein, Repressor of ga1-3 (RGA). Both ATIs promoted accumulation of GFP-fused RGA in shoots and roots, and this increase was counteracted by the application of GA4. These results suggest that in ATI-treated seedlings the impediment to DELLA protein degradation may be a deficiency of bioactive GA at sites of GA response. It is proposed that the four different levels of AtGA20ox1 regulation observed here are imposed in a strict hierarchy: spatial (organ-, tissue-, cell-specific) > developmental > metabolic > auxin regulation. Thus results show that, in intact auxin- and auxin transport inhibitor-treated light-grown Arabidopsis seedlings, three other levels of regulation supersede the effects of auxin on AtGA20ox1
Stamen-derived bioactive gibberellin is essential for male flower development of Cucurbita maxima L.
Gibberellin (GA) signalling during pumpkin male flower development is highly regulated, including biosynthetic, perception, and transduction pathways. GA 20-oxidases, 3-oxidases, and 2-oxidases catalyse the final part of GA synthesis. Additionally, 7-oxidase initiates this part of the pathway in some cucurbits including Cucurbita maxima L. (pumpkin). Expression patterns for these GA-oxidase-encoding genes were examined by competitive reverse transcription-PCR (RT-PCR) and endogenous GA levels were determined during pumpkin male flower development. In young flowers, GA20ox3 transcript levels are high in stamens, followed by high levels of the GA precursor GA9. Later, just before flower opening, transcript levels for GA3ox3 and GA3ox4 increase in the hypanthium and stamens, respectively. In the stamen, following GA3ox4 expression, bioactive GA4 levels rise dramatically. Accordingly, catabolic GA2ox2 and GA2ox3 transcript levels are low in developing flowers, and increase in mature flowers. Putative GA receptor GID1b and DELLA repressor GAIPb transcript levels do not change in developing flowers, but increase sharply in mature flowers. Emasculation arrests floral development completely and leads to abscission of premature flowers. Application of GA4 (but not of its precursors GA12-aldehyde or GA9) restores normal growth of emasculated flowers. These results indicate that de novo GA4 synthesis in the stamen is under control of GA20ox3 and GA3ox4 genes just before the rapid flower growth phase. Stamen-derived bioactive GA is essential and sufficient for male flower development, including the petal and the pedicel growth
Adaptation to ER Stress Is Mediated by Differential Stabilities of Pro-Survival and Pro-Apoptotic mRNAs and Proteins
The accumulation of unfolded proteins in the endoplasmic reticulum (ER) activates a signaling cascade known as the unfolded protein response (UPR). Although activation of the UPR is well described, there is little sense of how the response, which initiates both apoptotic and adaptive pathways, can selectively allow for adaptation. Here we describe the reconstitution of an adaptive ER stress response in a cell culture system. Monitoring the activation and maintenance of representative UPR gene expression pathways that facilitate either adaptation or apoptosis, we demonstrate that mild ER stress activates all UPR sensors. However, survival is favored during mild stress as a consequence of the intrinsic instabilities of mRNAs and proteins that promote apoptosis compared to those that facilitate protein folding and adaptation. As a consequence, the expression of apoptotic proteins is short-lived as cells adapt to stress. We provide evidence that the selective persistence of ER chaperone expression is also applicable to at least one instance of genetic ER stress. This work provides new insight into how a stress response pathway can be structured to allow cells to avert death as they adapt. It underscores the contribution of posttranscriptional and posttranslational mechanisms in influencing this outcome