158 research outputs found
Revealed Relatedness: Mapping Industry Space
In this paper we measure technological relatedness between industries using a dataset on product portfolios of plants. For this purpose we first develop a general methodology to extract data on co-occurrences of classes (e.g. industries) in a single entity (e.g. a plant) to construct estimates of the relatedness between the classes. The core assumption, in line with the concept of economies of scope, is that if two products are produced in the same plant, this is an indication of relatedness between the industries the two products are a part of. Unlike earlier methods, we arrive at a Revealed Relatedness (RR) index that can be interpreted on a ratio scale, allows for the use of indirect (i.e. not directly observed) information on industry relatedness, and conceptualizes relatedness as being asymmetric or directed. Direction of relatedness provides information on, for example, the most likely direction of spillovers between two classes. We also graph the RR matrices using methods borrowed from social network analysis. The result is a visualization of the âindustry spaceâ and how that changes over time with structural transformation of the economy. In order to test the validity of the framework, the industry space is used to plot structural transformation paths of regions. It is shown that the RR matrix indeed has significant explanatory power for the composition and change of a regions portfolio of manufacturing industries, in spite of the fact that regional information played no role in its derivation. This confirms the quality of our RR estimates.technological relatedness, industry relations, industry space, revealed relatedness
Surviving in agglomerations: Plant evolution and the changing benefits of the local environment
Cities vary with regard to the characteristics of their economic life. A formal model by Duranton and Puga (2001) suggests a division of labour between diversified and specialized cities. Diversified cities (the ânursery citiesâ) provide a fertile environment for search and innovation. Specialized cities, by contrast, are better equipped to facilitate mass-production. In essence, this spurs firms to re-locate as they mature from the exploratory set-up stage to mass-production. In this article, we empirically test the assumptions behind this model by means of survival analysis using Swedish plant level data of over 11 000 plants. More specifically, we investigate the effects of local specialization and local diversity on plant survival at different ages of a plant and for different size categories of plants. Not all types of local diversity will be of value to a plant. Rather, we expect plants to benefit especially from local diversity in related industries. In a similar vein, cities with a large concentration of a broad range of activities in related trades may confer larger benefits than cities with a narrow specialization in the plantâs own industry. To quantify the degree of relatedness between industries, we use a new measure, Revealed Relatedness. This serves to identify technological relatedness by measuring economies of scope as implied by the structure of production portfolios of plants. The findings suggest that regional characteristics strongly influence the chances of a plant to survive. In general, the hypothesized specialization effects are only found when we look at related specialization. Large plants at high stages of maturity form the only exception to this. However, diversity effects are only visible when we take all local diversity into account, not just diversity in related industries. Moreover, it is only young firms that benefit from regional diversity. This indicates that the ânursery cityâ metaphor holds as much for small, prototype plants as for large mass-production plants.agglomeration economies, revealed relatedness, industry relations, Sweden
Revealed Relatedness: Mapping Industry Space
In this paper we measure technological relatedness between industries using a dataset on product portfolios of plants. For this purpose we first develop a general methodology to extract data on co-occurrences of classes (e.g. industries) in a single entity (e.g. a plant) to construct estimates of the relatedness between the classes. The core assumption, in line with the concept of economies of scope, is that if two products are produced in the same plant, this is an indication of relatedness between the industries the two products are a part of. Unlike earlier methods, we arrive at a Revealed Relatedness (RR) index that can be interpreted on a ratio scale, allows for the use of indirect (i.e. not directly observed) information on industry relatedness, and conceptualizes relatedness as being asymmetric or directed. Direction of relatedness provides information on, for example, the most likely direction of spillovers between two classes. We also graph the RR matrices using methods borrowed from social network analysis. The result is a visualization of the âindustry spaceâ and how that changes over time with structural transformation of the economy. In order to test the validity of the framework, the industry space is used to plot structural transformation paths of regions. It is shown that the RR matrix indeed has significant explanatory power for the composition and change of a regions portfolio of manufacturing industries, in spite of the fact that regional information played no role in its derivation. This confirms the quality of our RR estimates.
Paint it Black â To Protect the Qubits
This thesis deals with reducing quasiparticle generation in superconducting circuits caused by stray photons by utilizing electromagnetic absorbers. This thesis deals with reducing quasiparticle generation in superconducting circuits caused by stray photons by utilizing electromagnetic absorbers. Quasiparticle generation is a known problem in several superconducting circuit applications such as quantum computing research. In order to quantify successful radiation reduction, a superconducting resonator was used as a sensor and a cylindrical shield was designed for testing the absorbers. Four different absorbers were tested, three of them are commercially available microwave absorbers and one was designed by our group. Internal differences were observed between the absorbers, however, compared to reference measurements, no improvements were observed. The results also indicates that the resonators properties changed in-between measurements and more tests should be performed in order to draw final conclusions
Who Needs Agglomeration? Varying Agglomeration Externalities and the Industry Life Cycle
In this paper, the changing roles of agglomeration externalities during different stages of the industry life cycle are investigated. A central argument is that agglomeration externalities vary with mode of competition, innovation intensity, and characteristics of learning opportunities in industries. Following the Industry Life Cycle perspective, we distinguish between young and mature industries, and investigate how these benefit from MAR, Jacobsâ and Urbanization externalities. The empirical analysis builds on a Swedish plant level dataset that covers the period of 1974-2004.The outcomes of panel data regression models show that the benefits industries derive from their local environment are strongly associated with their stage in the industry life cycle. Whereas MAR externalities increase with the maturity of industries, Jacobsâ externalities decline when industries are more mature. This is in line with the hypothesis that young industries operate in an environment dominated by rapid product innovation and low levels of standardization. Hence, it pays off when knowledge can be sourced locally from many different sources, but there is still little scope for specialization benefits. Mature industries, in contrast, are associated with lower innovation intensities and a focus on cost saving process innovations. Therefore, there are major benefits to be derived from specialization, whereas knowledge spillovers from different industries are less relevant. The distinction between the product competition in young industries and price competition in mature industries is reflected in our finding that high regional factor costs are detrimental to mature industries, but not to young industries. This can also be related to the finding that high quality living environments, attractive for highly paid employees, are important to young industries. Overall, the outcomes stress that industrial life cycles have to be taken into account in the analysis of agglomeration externalities.agglomeration externalities, industry life cycle, urbanization, Sweden
2009,06: Skill-relatedness and firm diversification
The concept of "relatedness" between industries plays an increasingly central role in economics and strategic management. However, relatedness has remained rather elusive in empirical terms. In this article, we investigate relatedness between industries in terms of the extent to which the same human capital can be employed in different industries. In particular, we investigate the skill-relatedness among different industries by investigating labor flows between industries. The data used are Swedish employer linked data on individuals. Our statistical framework assesses the degree to which labor flows between pairs of industries are in excess of expected levels and use this as a quantification of Revealed Skill Relatedness. A network picture of 435 4-digit industries and the relatedness linkages between them shows that the relations among industries are far more complex than the industrial classification system suggests. Moreover, when investigating corporate diversification, we find that firms are far more likely to diversify into industries that are strongly skill-related to their core activities industries than into unrelated industries
The Dynamics of Agglomeration Externalities along the Life Cycle of Industries
This paper investigates the changing roles of agglomeration externalities along the industry life cycle. We argue that industries have different agglomeration needs in different stages of their life cycles because their mode of competition, innovation intensity, and characteristics of learning opportunities change over time. For 12 Swedish manufacturing industries, we determined for each year between 1974 and 2004 whether the industry was in a young, intermediate, or mature stage. Whereas MAR externalities steadily increased with the maturity of industries, the effect of local diversity (Jacobsâ externalities) was positive for young industries but declined and even became negative for more mature industries
The validity of plagioclase-melt geothermometry for degassing-driven magma crystallization
Any quantitative interpretation of the formation conditions of igneous rocks requires methods for determining crystallization temperature. Accurate application of such thermobarometers relies on the attainment of equilibrium in the system to be studied. This may be particularly difficult in silicic magmas, where diffusivities are low and crystallization kinetics sluggish. Moreover, progressive degassing of volatile-rich magmas during ascent can result in continuous changes in effective undercooling, causing particular problems in achieving equilibrium between melt and crystals that grow in response to decompression. We consider these problems in the context of plagioclase-melt equilibria for magmas undergoing decompression and degassing-driven crystallization, using two published thermometers. The two thermometers show similar trends with key parameters but absolute temperatures can vary significantly. Analysis of decompression experiments conducted at constant temperature shows systematic variations in calculated temperature and equilibrium constant with varying decompression rate and quench pressure. This indicates that an unrecognized lack of equilibration could result in significant temperature overestimates and potentially spurious results. This highlights the need to assess for equilibrium, and we discuss problems associated with some commonly used indicators of equilibration. Finally, retrospective analysis of published plagioclase-hosted melt inclusion suites from five subduction zone volcanoes shows systematic increases in calculated temperature and decreases in equilibrium constant with decreasing H2O concentration. While this could represent the signature of latent heat of crystallization, we suggest that such patterns should be treated with caution unless there is clear evidence of sustained equilibrium between plagioclase and melt during decompression.M.C.S.H. acknowledges support from a Royal Society University Research Fellowship.This is the author accepted manuscript. The final version is available from the Mineralogical Society of America via http://dx.doi.org/10.2138/am-2016-531
The SNARE Protein SNAP23 and the SNARE-Interacting Protein Munc18c in Human Skeletal Muscle Are Implicated in Insulin Resistance/Type 2 Diabetes
OBJECTIVE-Our previous studies suggest that the SNARE protein synaptosomal-associated protein of 23 kDa (SNAP23) is involved in the link between increased lipid levels and insulin resistance in cardiomyocytes. The objective was to determine whether SNAP23 may also be involved in the known association between lipid accumulation in skeletal muscle and insulin resistance/type 2 diabetes in humans, as well as to identify a potential regulator of SNAP23. RESEARCH DESIGN AND METHODS-We analyzed skeletal muscle biopsies from patients with type 2 diabetes and healthy, insulin-sensitive control subjects for expression (mRNA and protein) and intracellular localization (subcellular fractionation and immunohistochemistry) of SNAP23, and for expression of proteins known to interact with SNARE proteins. Insulin resistance was determined by a euglycemic hyperinsulinemic clamp Potential mechanisms for regulation of SNAP23 were also investigated in the skeletal muscle cell line L6. RESULTS-We showed increased SNAP23 levels in skeletal muscle from patients with type 2 diabetes compared with that from lean control subjects Moreover, SNAP23 was redistributed from the plasma membrane to the microsomal/cytosolic compartment in the patients with the type 2 diabetes Expression of the SNARE-interacting protein Munc18c was higher in skeletal muscle from patients with type 2 diabetes Studies in L6 cells showed that Munc18c promoted the expression of SNAP23. CONCLUSIONS-We have translated our previous in vitro results into humans by showing that there is a change in the distribution of SNAP23 to the interior of the cell in skeletal muscle from patients with type 2 diabetes. We also showed that Munc18c is a potential regulator of SNAP23. Diabetes 59: 1870-1878, 201
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