The Optimal Rate of Decline of an Inefficient Industry

This paper considers the problem of the optimal time path of contraction of an industry which has been hit by foreign competition, and shows that in general, along the optimal path, a production subsidy is warranted. The optimal subsidy trades off the benefit of unemployment in speeding up the approach to the new long-run equilibrium against the cost of lost output in the ‘inefficient’ industry. The dynamic shadow price of labour in this industry is also derived and shown to be always positive, though below the industry wage rat

Alignment of the Angular Momentum Vectors of Planetary Nebulae in the Galactic Bulge

We use high-resolution H {\alpha} images of 130 planetary nebulae (PNe) to investigate whether there is a preferred orientation for PNe within the Galactic Bulge. The orientations of the full sample have an uniform distribution. However, at a significance level of 0.01, there is evidence for a non-uniform distribution for those planetary nebulae with evident bipolar morphology. If we assume that the bipolar PNe have an unimodal distribution of the polar axis in Galactic coordinates, the mean Galactic position angle is consistent with 90{\deg}, i.e. along the Galactic plane, and the significance level is better than 0.001 (the equivalent of a 3.7{\sigma} significance level for a Gaussian distribution). The shapes of PNe are related to angular momentum of the original star or stellar system, where the long axis of the nebula measures the angular momentum vector. In old, low-mass stars, the angular momentum is largely in binary orbital motion. Consequently, the alignment of bipolar nebulae that we have found indicates that the orbital planes of the binary systems are oriented perpendicular to the Galactic plane. We propose that strong magnetic fields aligned along the Galactic plane acted during the original star formation process to slow the contraction of the star forming cloud in the direction perpendicular to the plane. This would have produced a propensity for wider binaries with higher angular momentum with orbital axes parallel to the Galactic plane. Our findings provide the first indication of a strong, organized magnetic field along the Galactic plane that impacted on the angular momentum vectors of the resulting stellar population.Comment: There are two effective parts. The main paper consists of the first 17 pages and includes 8 figures and 7 tables. The remaining 10 pages will be published as an online supplement that is made up of 4 multi-part figures. Accepted for publication in MNRAS Main Journa

How many metals does it take to fix N2? A mechanistic overview of biological nitrogen fixation

During the process of biological nitrogen fixation, the enzyme nitrogenase catalyzes the ATP-dependent reduction of dinitrogen to ammonia. Nitrogenase consists of two component metalloproteins, the iron (Fe) protein and the molybdenum-iron (MoFe) protein; the Fe protein mediates the coupling of ATP hydrolysis to interprotein electron transfer, whereas the active site of the MoFe protein contains the polynuclear FeMo cofactor, a species composed of seven iron atoms, one molybdenum atom, nine sulfur atoms, an interstitial light atom, and one homocitrate molecule. This Perspective provides an overview of biological nitrogen fixation and introduces three contributions to this special feature that address central aspects of the mechanism and assembly of nitrogenase

Nitrogenase: A nucleotide-dependent molecular switch

In the simplest terms, the biological nitrogen cycle is the reduction of atmospheric dinitrogen (N2) to ammonia with the subsequent reoxidation ammonia to dinitrogen (1). At the reduction level of ammonia, nitrogen incorporated into precursors for biological macromolecules such as proteins and nucleic acids. Reoxidation of ammonia to dinitrogen ("denitrification") by a variety of microbes (by way of nitrite and other oxidation levels of nitrogen) leads to the depletion of the "fixed," biologically usable, nitrogen pool. Besides the relatively small contribution from commercial ammonical fertilizer production, replenishing of the nitrogen pool falls mainly to a limited number of physiologically diverse microbes (e.g. eubacteria and archaebacteria; free-living and symbiotic; aerobic and anaerobic) that contain the nitrogenase enzyme system

Time Delay Compensation and Stability Analysis of Networked Predictive Control Systems Based on Hammerstein Model

A novel approach is proposed for a networked control system with random delays containing a nonlinear process based on a Hammerstein model. The method uses a time delay two step generalized predictive control (TDTSGPC), which consists of two parts, one is to deal with the input nonlinearity of the Hammerstein model and the other is to compensate the network induced delays in the networked control system. Theoretical results using the Popov theorem are presented for the closed-loop stability of the system in the case of a constant delay. Simulation examples illustrating the validity of the approach are presented

The Optimal Rate of Decline of an Inefficient Industry

This paper considers the problem of the optimal time path of contraction of an industry which has been hit by foreign competition, and shows that in general, along the optimal path, a production subsidy is warranted. The optimal subsidy trades off the benefit of unemployment in speeding up the approach to the new long-run equilibrium against the cost of lost output in the ‘inefficient’ industry. The dynamic shadow price of labour in this industry is also derived and shown to be always positive, though below the industry wage rate

Internal Migration and Regional Population Dynamics in Europe: France Case Study

The paper examines the patterns of internal migration and population change in France over the recent decades at departément and commune scales. Regional population change is controlled by both natural increase and internal migration. There are two differing patterns of natural increase: north and east France has higher natural increase and south and east has lower. The geographic pattern of internal migration has changed substantially over the last 50 years, most dramatically in the Île-de-France, which showed the highest gains between 1954 and 1962 but the highest losses between 1975 and 1982. Urban growth, which was strong in the 1950s and 1960s, reversed in the 1970s favouring small towns but recovered slightly in the last 20 years. Migration gains and losses show a quite complicated pattern of depopulation of city centres combined with slow suburbanisation and advanced periurbanisation. Periurbanisation is evident in Paris region and in nearly all large urban agglomerations. Most other cities show suburbanisation or periurbanisation at various stages of development. Out-migration shows a clear division of the country into a northern part with higher rates, and a central and southern part of the country with lower out-migration. This simple pattern is modified by higher out-migration from some cities such as Lyon or Clermont-Ferrand and from isolated rural communes scattered all over the country. Out-migration also has a regional dimension: there are shifts towards more attractive areas, in particular Alpine region and Mediterranean and Atlantic coasts. Analysis of migration between size bands of rural and urban units shows a significant deconcentration process, and a similar pattern characterises migration between population density bands. The general movement is down the urban/density band hierarchy, from higher to lower urban/density bands. Deep rural areas are not attractive and excluded from the process of counterurbanisation. In addition, unemployment was found to have a strong and very efficient impact on migration behaviour. Analysis for 1990-1999 leads to slight modification of this picture: a slow recovery of central parts of the largest urban agglomerations and less differentiated patterns than in the 1980s. Deconcentration of the French population continues but is less powerful

Encoding of temporal probabilities in the human brain

Anticipating the timing of future events is a necessary precursor to preparing actions and allocating resources to sensory processing. This requires elapsed time to be represented in the brain and used to predict the temporal probability of upcoming events. While neuropsychological, imaging, magnetic stimulation studies, and single-unit recordings implicate the role of higher parietal and motor-related areas in temporal estimation, the role of earlier, purely sensory structures remains more controversial. Here we demonstrate that the temporal probability of expected visual events is encoded not by a single area but by a wide network that importantly includes neuronal populations at the very earliest cortical stages of visual processing. Moreover, we show that activity in those areas changes dynamically in a manner that closely accords with temporal expectations

Family Effects in Youth Employment

The authors begin with the hypothesis that parental contacts play a major role in finding jobs for youth. This hypothesis is tested with a model of youth employment that includes characteristics of other family members in addition to a large set of control variables. Particular attention is paid to parental characteristics that might indicate a parent's ability to assist the youth in finding a job, including occupation, industry and education. The effects of such variables are generally not significant and do not support the initial hypothesis. However, the employment probability of a youth is significantly affected by the presence of employed siblings, indicating the presence of some intrafamily effects.

Developing Competent Managers: The Shadow of Hungarian History

Hungary is deemed to be one of the economies that has successfully undergone the changes needed to enter the European Union. Despite this, it has been pointed out that Hungarian managers are still lacking in education and training, that there is a lack of innovation, and that there is still a certain resistance to change manifest in the continuance of the ‘black market’ economy. However, it is optimistically expected that the influx of Western managerial practices will soon put this to rights (Agenda 2000). In this paper, we question these assumptions. Firstly, we argue that change is a more complex sociological and historical phenomenon than most organisational writers would have us believe. To illustrate this point, we draw on the work of the social historian Elias, who shows us that macro-societal developments and changes at the micro-level are interrelated. Following Elias, we then examine the nature of change at an institutional level in Hungary, set against the wider historical background that has shaped these changes. Then, drawing on literature and social research into values, we examine the nature of the Hungarian character, showing its development alongside and in tandem with the historical and institutional changes. What we find does not reflect the upbeat representation of the current Hungarian situation. Rather, using the language of Jung, we show that the particular historical changes that have taken place seem to have taken place at two levels, leading to a ‘split’ in Hungarian institutions (of which we consider the economy an example) and which is equally reflected by an ‘alienation’ in the Hungarian character. We question the notion that the practices recently being imported from the West will provide the solutions that the Hungarian economy is looking for. Indeed, there is a possibility that the wholesale importation of such practices may add to the ‘alienated’ nature of Hungarian organisations, and increase the split between the rulers and the ruled, whether we conceive of this at an institutional level, or at the level of the individual psyche. We suggest that, without understanding these deeper issues, the simple importation of Western ideas is unlikely to address the need to implement lasting changes in organisations and to develop competent and creative managers