Job (In)Security and Workers’ Training Decisions: A Framing Approach

Context: In this study, we attempt to contribute to the scarce evidence about the relationship between perceived labour market insecurity and worker training investments. Drawing on existing research into framing in decision-making, we investigate whether framing the labour market as insecure increases the willingness of workers to invest in training. We also investigate whether this effect is larger when training contract terms are favourable, such as when training is done mostly in an employer’s time, or when no payback clause is included.Approach: Data are gathered through a vignette-study under a sample of senior Dutch students, with experimental manipulation of frames. Respondents are given a questionnaire in which they are asked to imagine themselves working for a fictitious firm (but presented to them as real). The security/insecurity frames are elicited by randomly stressing either the positive or negative side of a series of events related to the labour market position of people working in this firm. Respondents are then asked to respond to five vignettes, each of these a randomly generated combination of training contract terms. For each vignette, respondents are asked to state whether or not they would be willing to go along with the specified training program under the conditions outlined in that vignette. Data are analysed with multilevel logistic regression. Findings: The willingness to train is not invariably greater under an insecurity frame. Instead, we find a crucial interaction: the willingness to train is greater under an insecurity frame when training-contract terms are favourable (e.g when no payback clause is included), but smaller when training-contract terms are unfavourable. Since the positive and negative effects are approximately equal in size, in a balanced design such as ours they cancel each other out, resulting in a close to zero overall effect for the frame variable.Conclusion: Our results suggest that, when workers are aware of the insecurity in their situation, this only makes them more willing to follow training when the risk of losing their investment is low.

Extended HI spiral structure and the figure rotation of triaxial dark halos

The HI disk of the blue compact dwarf (BCD) galaxy NGC 2915 extends to 22 optical scalelengths and shows spiral arms reaching far beyond the optical component. None of the previous theories for spiral structure provide likely explanations for these very extended spiral arms. Our numerical simulations first demonstrate that such large spiral arms can form in an extended gas disk embedded in a massive triaxial dark matter halo with slow figure rotation, through the strong gravitational torque of the rotating halo. We then show that the detailed morphological properties of the developed spirals and rings depend strongly on the pattern speed of the figure rotation, the shape of the triaxial halo, and the inclination of the disk with respect to the plane including the triaxial halo's long and middle axes. These results strongly suggest that the dark matter halo of NGC 2915 is triaxial and has figure rotation. Based on these results, we also suggest that dynamical effects of triaxial halos with figure rotation are important in various aspect of galaxy formation and evolution, such as formation of polar ring galaxies, excitation of non-axisymmetric structures in low surface-brightness galaxies, and gas fueling to the central starburst regions of BCDs.Comment: 13 pages 2 figures (fig.2 = jpg format), accepted by ApJ

A Test of the Standard Hypothesis for the Origin of the HI Holes in Holmberg II

The nearby irregular galaxy Holmberg II has been extensively mapped in HI using the Very Large Array (VLA), revealing intricate structure in its interstellar gas component (Puche et al. 1992). An analysis of these structures shows the neutral gas to contain a number of expanding HI holes. The formation of the HI holes has been attributed to multiple supernova events occurring within wind-blown shells around young, massive star clusters, with as many as 10-200 supernovae required to produce many of the holes. From the sizes and expansion velocities of the holes, Puche et al. assigned ages of ~10^7 to 10^8 years. If the supernova scenario for the formation of the HI holes is correct, it implies the existence of star clusters with a substantial population of late-B, A and F main sequence stars at the centers of the holes. Many of these clusters should be detectable in deep ground-based CCD images of the galaxy. In order to test the supernova hypothesis for the formation of the HI holes, we have obtained and analyzed deep broad-band BVR and narrow-band H-alpha images of Ho II. We compare the optical and HI data and search for evidence of the expected star clusters in and around the HI holes. We also use the HI data to constrain models of the expected remnant stellar population. We show that in several of the holes the observed upper limits for the remnant cluster brightness are strongly inconsistent with the SNe hypothesis described in Puche et al. Moreover, many of the HI holes are located in regions of very low optical surface brightness which show no indication of recent star formation. Here we present our findings and explore possible alternative explanations for the existence of the HI holes in Ho II, including the suggestion that some of the holes were produced by Gamma-ray burst events.Comment: 30 pages, including 6 tables and 3 images. To appear in Astron. Journal (June 1999

A flexible data architecture to automate collection of (near) real-time methane sensor data at commercial dairy farms

To reduce methane emissions from the animal production domain, a large intensive research programme has been started in 2018 by the Dutch Ministry of Agriculture, Nature and Food. Part of this programme involves continuous monitoring of methane, by means of sensor measurements, both at the barn and ..

3D MHD Modeling of the Gaseous Structure of the Galaxy: Setup and Initial Results

We show the initial results of our 3D MHD simulations of the flow of the Galactic atmosphere as it responds to a spiral perturbation in the potential. In our standard case, as the gas approaches the arm, there is a downward converging flow that terminates in a complex of shocks just ahead of the midplane density peak. The density maximum slants forward at high z, preceeded by a similarly leaning shock. The latter diverts the flow upward and over the arm, as in a hydraulic jump. Behind the gaseous arm, the flow falls again, generating further secondary shocks as it approaches the lower z material. Structures similar to the high z part of the gaseous arms are found in the interarm region of our two-armed case, while broken arms and low column density bridges are present in the four-armed case. We present three examples of what can be learned from these models.Comment: 33 pages, 17 figures. Accepted for publication in Apj. Better quality images in http://www.journals.uchicago.edu/ApJ/journal/preprints/ApJ55782.preprint.pd

Using Data Lake Stack in Animal Sciences

Big Data is a theme that receives a lot of attention, and is often characterised as managing and analysing large datasets to reveal new valuable patterns. In the livestock domain, big data is also becoming more common and is being anchored into the mind-set of researchers, due to, for example, sensors generating ..