Industrial Location and Space: New Insights

This paper tries to resolve some of the main shortcomings in the empirical literature of location decisions for new plants, i.e. spatial effects and overdispersion. Spatial effects are omnipresent, being a source of overdispersion in the data as well as a factor shaping the functional relationship between the variables that explain a firm’s location decisions. Using Count Data models, empirical researchers have dealt with overdispersion and excess zeros by developments of the Poisson regression model. This study aims to take this a step further, by adopting Bayesian methods and models in order to tackle the excess of zeros, spatial and non-spatial overdispersion and spatial dependence simultaneously. Data for Catalonia is used and location determinants are analysed to that end. The results show that spatial effects are determinant. Additionally, overdispersion is descomposed into an unstructured iid effect and a spatially structured effect. Keywords: Bayesian Analysis, Spatial Models, Firm Location. JEL Classification: C11, C21, R30.

Electrode location and clinical outcome in hippocampal electrical stimulation for mesial temporal lobe epilepsy.

PURPOSE: To study the clinical outcome in hippocampal deep brain stimulation (DBS) for the treatment of patients with refractory mesial temporal lobe epilepsy (MTLE) according to the electrode location. METHODS: Eight MTLE patients implanted in the hippocampus and stimulated with high-frequency DBS were included in this study. Five underwent invasive recordings with depth electrodes to localize ictal onset zone prior to chronic DBS. Position of the active contacts of the electrode was calculated on postoperative imaging. The distances to the ictal onset zone were measured as well as atlas-based hippocampus structures impacted by stimulation were identified. Both were correlated with seizure frequency reduction. RESULTS: The distances between active electrode location and estimated ictal onset zone were 11±4.3 or 9.1±2.3mm for patients with a >50% or <50% reduction in seizure frequency. In patients (N=6) showing a >50% seizure frequency reduction, 100% had the active contacts located <3mm from the subiculum (p<0.05). The 2 non-responders patients were stimulated on contacts located >3mm to the subiculum. CONCLUSION: Decrease of epileptogenic activity induced by hippocampal DBS in refractory MTLE: (1) seems not directly associated with the vicinity of active electrode to the ictal focus determined by invasive recordings; (2) might be obtained through the neuromodulation of the subiculum.

The problem of the competitiveness of nuclear energy: a biophysical explanation

In this study I try to explain the systemic problem of the low economic competitiveness of nuclear energy for the production of electricity by carrying out a biophysical analysis of its production process. Given the fact that neither econometric approaches nor onedimensional methods of energy analyses are effective, I introduce the concept of biophysical explanation as a quantitative analysis capable of handling the inherent ambiguity associated with the concept of energy. In particular, the quantities of energy, considered as relevant for the assessment, can only be measured and aggregated after having agreed on a pre-analytical definition of a grammar characterizing a given set of finite transformations. Using this grammar it becomes possible to provide a biophysical explanation for the low economic competitiveness of nuclear energy in the production of electricity. When comparing the various unit operations of the process of production of electricity with nuclear energy to the analogous unit operations of the process of production of fossil energy, we see that the various phases of the process are the same. The only difference is related to characteristics of the process associated with the generation of heat which are completely different in the two systems. Since the cost of production of fossil energy provides the base line of economic competitiveness of electricity, the (lack of) economic competitiveness of the production of electricity from nuclear energy can be studied, by comparing the biophysical costs associated with the different unit operations taking place in nuclear and fossil power plants when generating process heat or net electricity. In particular, the analysis focuses on fossil-fuel requirements and labor requirements for those phases that both nuclear plants and fossil energy plants have in common: (i) mining; (ii) refining/enriching; (iii) generating heat/electricity; (iv) handling the pollution/radioactive wastes. By adopting this approach, it becomes possible to explain the systemic low economic competitiveness of nuclear energy in the production of electricity, because of: (i) its dependence on oil, limiting its possible role as a carbon-free alternative; (ii) the choices made in relation to its fuel cycle, especially whether it includes reprocessing operations or not; (iii) the unavoidable uncertainty in the definition of the characteristics of its process; (iv) its large inertia (lack of flexibility) due to issues of time scale; and (v) its low power level.

Growth in a Cross-Section of Cities: Location, Increasing Returns or Random Growth?

This article analyzes empirically the main existing theories on income and population city growth: increasing returns to scale, locational fundamentals and random growth. To do this we implement a threshold nonlinearity test that extends standard linear growth regression models to a dataset on urban, climatological and macroeconomic variables on 1,175 U.S. cities. Our analysis reveals the existence of increasing returns when per-capita income levels are beyond $19; 264. Despite this, income growth is mostly explained by social and locational fundamentals. Population growth also exhibits two distinct equilibria determined by a threshold value of 116,300 inhabitants beyond which city population grows at a higher rate. Income and population growth do not go hand in hand, implying an optimal level of population beyond which income growth stagnates or deteriorates

Multisensory mechanisms in temporo-parietal cortex support self-location and first-person perspective.

Self-consciousness has mostly been approached by philosophical enquiry and not by empirical neuroscientific study, leading to an overabundance of diverging theories and an absence of data-driven theories. Using robotic technology, we achieved specific bodily conflicts and induced predictable changes in a fundamental aspect of self-consciousness by altering where healthy subjects experienced themselves to be (self-location). Functional magnetic resonance imaging revealed that temporo-parietal junction (TPJ) activity reflected experimental changes in self-location that also depended on the first-person perspective due to visuo-tactile and visuo-vestibular conflicts. Moreover, in a large lesion analysis study of neurological patients with a well-defined state of abnormal self-location, brain damage was also localized at TPJ, providing causal evidence that TPJ encodes self-location. Our findings reveal that multisensory integration at the TPJ reflects one of the most fundamental subjective feelings of humans: the feeling of being an entity localized at a position in space and perceiving the world from this position and perspective.

Detecció i localització d'impactes a estructures aeroespacials

Projecte de recerca elaborat a partir d’una estada a la Universidad Politécnica de Madrid, Espanya, entre setembre i o desembre del 2007. Actualment la indústria aeroespacial i aeronàutica té com prioritat millorar la fiabilitat de las seves estructures a través del desenvolupament de nous sistemes per a la monitorització i detecció d’impactes. Hi ha diverses tècniques potencialment útils, i la seva aplicabilitat en una situació particular depèn críticament de la mida del defecte que permet l’estructura. Qualsevol defecte canviarà la resposta vibratòria de l’element estructural, així com el transitori de l’ona que es propaga per l’estructura elàstica. Correlacionar aquests canvis, que poden ser detectats experimentalment amb l’ocurrència del defecte, la seva localització i quantificació, és un problema molt complex. Aquest treball explora l’ús de l'Anàlisis de Components Principals (Principal Component Analysis - PCA-) basat en la formulació dels estadístics T2 i Q per tal de detectar i distingir els defectes a l'estructura, tot correlacionant els seus canvis a la resposta vibratòria. L’estructura utilitzada per l’estudi és l’ala d’una turbina d’un avió comercial. Aquesta ala s’excita en un extrem utilitzant un vibrador, i a la qual s'han adherit set sensors PZT a la superfície. S'aplica un senyal conegut i s'analitzen les respostes. Es construeix un model PCA utilitzant dades de l’estructura sense defecte. Per tal de provar el model, s'adhereix un tros d’alumini en quatre posicions diferents. Les dades dels assajos de l'estructura amb defecte es projecten sobre el model. Les components principals i les distàncies de Q-residual i T2-Hotelling s'utilitzaran per a l'anàlisi de les incidències. Q-residual indica com de bé s'adiu cadascuna de les mostres al model PCA, ja que és una mesura de la diferència, o residu, entre la mostra i la seva projecció sobre les components principals retingudes en el model. La distància T2-Hotelling és una mesura de la variació de cada mostra dins del model PCA, o el que vindria a ser el mateix, la distància al centre del model PCA.

Estimating the Prevalence of Problem Opiate and Problem Cocaine Use in Northern Ireland (PDF 213 KB)

Apr-06

GLUT4, AMP kinase, but not the insulin receptor, are required for hepatoportal glucose sensor-stimulated muscle glucose utilization.

Recent evidence suggests the existence of a hepatoportal vein glucose sensor, whose activation leads to enhanced glucose use in skeletal muscle, heart, and brown adipose tissue. The mechanism leading to this increase in whole body glucose clearance is not known, but previous data suggest that it is insulin independent. Here, we sought to further determine the portal sensor signaling pathway by selectively evaluating its dependence on muscle GLUT4, insulin receptor, and the evolutionarily conserved sensor of metabolic stress, AMP-activated protein kinase (AMPK). We demonstrate that the increase in muscle glucose use was suppressed in mice lacking the expression of GLUT4 in the organ muscle. In contrast, glucose use was stimulated normally in mice with muscle-specific inactivation of the insulin receptor gene, confirming independence from insulin-signaling pathways. Most importantly, the muscle glucose use in response to activation of the hepatoportal vein glucose sensor was completely dependent on the activity of AMPK, because enhanced hexose disposal was prevented by expression of a dominant negative AMPK in muscle. These data demonstrate that the portal sensor induces glucose use and development of hypoglycemia independently of insulin action, but by a mechanism that requires activation of the AMPK and the presence of GLUT4.

Prevalence of Problem Heroin Use in NI (PDF 227 KB)

Mar-02

What underlies localization and urbanization economies? Evidence from the location of new firms

The objective of this paper is to analyze why firms in some industries locate in specialized economic environments (localization economies) while those in other industries prefer large city locations (urbanization economies). To this end, we examine the location decisions of new manufacturing firms in Spain at the city level and for narrowly defined industries (three-digit level). First, we estimate firm location models to obtain estimates that reflect the importance of localization and urbanization economies in each industry. In a second step, we regress these estimates on industry characteristics that are related to the potential importance of three agglomeration theories, namely, labor market pooling, input sharing and knowledge spillovers. Localization effects are low and urbanization effects are high in knowledge-intensive industries, suggesting that firms (partly) locate in large cities to reap the benefits of inter-industry knowledge spillovers. We also find that localization effects are high in industries that employ workers whose skills are more industry-specific, suggesting that industries (partly) locate in specialized economic environments to share a common pool of specialized workers.

Report of the National Taskforce on Obesity: Obesity - the policy challenges: Executive Summary

The prevalence of overweight and obesity has increased with alarming speed over the past twenty years. It has recently been described by the World Health Organisation as a ‘global epidemic’. In the year 2000 more than 300 million people worldwide were obese and it is now projected that by 2025 up to half the population of the United States will be obese if current trends are maintained. The disease is now a major public health problem throughout Europe. In Ireland at the present time 39% of adults are overweight and 18% are obese. Of these, slightly more men than women are obese and there is a higher incidence of the disease in lower socio-economic groups. Most worrying of all is the fact that childhood obesity has reached epidemic proportions in Europe, with body weight now the most prevalent childhood disease. While currently there are no agreed criteria or standards for assessing Irish children for obesity some studies are indicating that the numbers of children who are significantly overweight have trebled over the past decade. Extrapolation from authoritative UK data suggests that these numbers could now amount to more than 300,000 overweight and obese children on the island of Ireland and they are probably rising at a rate of over 10,000 per year. A balance of food intake and physical activity is necessary for a healthy weight. The foods we individually consume and our participation in physical activity are the result of a complex supply and production system. The growing research evidence that energy dense foods promote obesity is impressive and convincing. These are the foods that are high in fat, sugar and starch. Of these potentially the most significant promoter of weight gain is fat and foods from the top shelf of the food pyramid including spreads (butter and margarine), cakes and biscuits, and confectionery, when combined are the greatest contributors to fat intake in the Irish diet. In company with their adult counterparts Irish children are also consuming large amounts of energy dense foods outside the home. A recent survey revealed that slightly over half of these children ate sweets at least once a day and roughly a third of them had fizzy drinks and crisps with the same regularity. Sugar sweetened carbonated drinks are thought to contribute to obesity and for this reason the World Health Organisation has expressed serious concerns at the high and increasing consumption of these drinks by children. Physical activity is an important determinant of body weight. Over recent decades there has been a marked decline in demanding physical work and this has been accompanied by more sedentary lifestyles generally and reduced leisure-time activity. These observable changes, which are supported by data from most European countries and the United States, suggest that physical inactivity has made a significant impact on the increase in overweight and obesity being seen today. It is now widely accepted that adults shoud be involved in 45-60 minutes, and children should be involved in at least 60 minutes per day of moderate physical activity in order to prevent excess weight gain. Being overweight today not only signals increased risk of medical problems but also exposes people to serious psychosocial problems due mainly to widespread prejudice against fat people. Prejudice against obese people seems to border on the socially acceptable in Ireland. It crops up consistently in surveys covering groups such as employers, teachers, medical and healthcare personnel, and the media. It occurs among adolescents and children, even very young children. Because obesity is associated with premature death, excessive morbidity and serious psychosocial problems the damage it causes to the welfare of citizens is extremely serious and for this reason government intervention is necessary and warranted. In economic terms, a figure of approximately â,¬30million has been estimated for in-patient costs alone in 2003 for a number of Irish hospitals. This year about 2,000 premature deaths in Ireland will be attributed to obesity and the numbers are growing relentlessly. Diseases which proportionally more obese people suffer from than the general population include hypertension, type 2 diabetes, angina, heart attack and osteoarthritis. There are indirect costs also such as days lost to the workplace due to illness arising from obesity and output foregone as a result of premature death. Using the accepted EU environmental cost benefit method, these deaths alone may be costing the state as much as â,¬4bn per year. The social determinants of physical activity include factors such as socio-economic status, education level, gender, family and peer group influences as well as individual perceptions of the benefits of physical activity. The environmental determinants include geographic location, time of year, and proximity of facilities such as open spaces, parks and safe recreational areas generally. The environmental factors have not yet been as well studied as the social ones and this research gap needs to be addressed. Clearly there is a public health imperative to ensure that relevant environmental policies maximise opportunities for active transport, recreational physical activity and total physical activity. It is clear that concerted policy initiatives must be put in place if the predominantly negative findings of research regarding the determinants of food consumption and physical activity are to be accepted, and they must surely be accepted by government if the rapid increase in the incidence of obesity with all its negative consequences for citizens is to be reversed. So far actions surrounding nutrition policies have concentrated mostly on actions that are within the remit of the Department of Health and Children such as implementing the dietary guidelines. These are important but government must now look at the totality of policies that influence the type and supply of food that its citizens eat and the range and quality of opportunities that are available to citizens to engage in physical activity. This implies a fundamental examination of existing agricultural, industrial, economic and other policies and a determination to change them if they do not enable people to eat healthily and partake in physical activity. The current crisis in obesity prevalence requires a population health approach for adults and children in addition to effective weight-reduction management for individuals who are severely overweight. This entails addressing the obesogenic environment where people live, creating conditions over time which lead to healthier eating and more active living, and protecting people from the widespread availability of unhealthy food and beverage options in addition to sedentary activities that take up all of their leisure time. People of course have a fundamental right to choose to eat what they want and to be as active as they wish. That is not the issue. What the National Taskforce on Obesity has had to take account of is that many forces are actively impeding change for those well aware of the potential health and well-being consequences to themselves of overweight and obesity. The Taskforce’s social change strategy is to give people meaningful choice. Choice, or the capacity to change (because the strategy is all about change), is facilitated through the development of personal skills and preferences, through supportive and participative environments at work, at school and in the local community, and through a dedicated and clearly communicated public health strategy. High-level cabinet support will be necessary to implement the Taskforce’s recommendations. The approach to implementation must be characterised by joined-up thinking, real practical engagement by the public and private sectors, the avoidance of duplication of effort or crosspurpose approaches, and the harnessing of existing strategies and agencies. The range of government departments with roles to play is considerable. The Taskforce outlines the different contributions that each relevant department can make in driving its strategy forward. It also emphasises its requirement that all phases of the national strategy for healthy eating and physical activity are closely monitored, analysed and evaluated. The vision of the Taskforce is expressed as: An Irish society that enables people through health promotion, prevention and care to achieve and maintain healthy eating and active living throughout their lifespan. Its high-level goals are expressed as follows: Its recommendations, over eighty in all, relate to actions across six broad sectors: high-level government; education; social and community; health; food, commodities, production and supply; and the physical environment. In developing its recommendations the Taskforce has taken account of the complex, multisectoral and multi-faceted determinants of diet and physical activity. This strategy poses challenges for government, within individual departments, inter-departmentally and in developing partnerships with the commercial sector. Equally it challenges the commercial sector to work in partnership with government. The framework required for such initiative has at its core the rights and benefits of the individual. Health promotion is fundamentally about empowerment, whether at the individual, the community or the policy level.