998 resultados para scope effect
Resumo:
Landscape is an example of a non-market good where no metrics exist to measure its quality. The paper proposes an original methodology to nevertheless estimate scope variables in those circumstances, allowing then to better test if people's willingnesstopay for such good is sensitive to the scope. The methodology is based on techniques developed in the context of multicriteria decision analysis. It is applied to assess the quality of the landscape of several Swiss alpine resorts. This assessment is then used as an explanatory variable in a hedonic price function to explain the rent of apartments and to derive an implicit price of the landscape quality.
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This article analyses how agglomeration economies shaped the location decisions of new manufacturing start-ups in Catalan municipalities in 2001-2005. We estimate whether the locations of new firms are spatially autocorrelated and whether this phenomenon is industry-specific. Our aim is to estimate the geographical scope of agglomeration economies on firm entries. The data set comes from a compulsory register of manufacturing establishments (REIC: Catalan Manufacturing Establishments Register). JEL classification: R1, R3 Keywords: firm location; spatial autocorrelation
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Ground delay programs typically involve the delaying of aircraft that are departing from origin airports within some set distance of a capacity constrained destination airport. Long haul flights are not delayed in this way. A trade-off exists when fixing the distance parameter: increasing the ‘scope’ distributes delay among more aircraft and may reduce airborne holding delay but could also result in unnecessary delay in the (frequently observed) case of early program cancellation. In order to overcome part of this drawback, a fuel based cruise speed reduction strategy aimed at realizing airborne delay, was suggested by the authors in previous publications. By flying slower, at a specific speed, aircraft that are airborne can recover part of their initially assigned delay without incurring extra fuel consumption if the ground delay program is canceled before planned. In this paper, the effect of the scope of the program is assessed when applying this strategy. A case study is presented by analyzing all the ground delay programs that took place at San Francisco, Newark Liberty and Chicago O’Hare International airports during one year. Results show that by the introduction of this technique it is possible to define larger scopes, partially reducing the amount of unrecovered delay.
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Flow pumps are important tools in several engineering areas, such as in the fields of bioengineering and thermal management solutions for electronic devices. Nowadays, many of the new flow pump principles are based on the use of piezoelectric actuators, which present some advantages such as miniaturization potential and lower noise generation. In previous work, authors presented a study of a novel pump configuration based on placing an oscillating bimorph piezoelectric actuator in water to generate flow. It was concluded that this oscillatory behavior (such as fish swimming) yields vortex interaction, generating flow rate due to the action and reaction principle. Thus, following this idea the objective of this work is to explore this oscillatory principle by studying the interaction among generated vortex from two bimorph piezoelectric actuators oscillating inside the same pump channel, which is similar to the interaction of vortex generated by frontal fish and posterior ones when they swim together in a group formation. It is shown that parallel-series configurations of bimorph piezoelectric actuators inside the same pump channel provide higher flow rates and pressure for liquid pumping than simple parallel-series arrangements of corresponding single piezoelectric pumps, respectively. The scope of this work includes structural simulations of bimorph piezoelectric actuators, fluid flow simulations, and prototype construction for result validation.
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21th Annual Conference of the International Group for Lean Construction (IGLC 21), July 2013, Fortaleza, Brazil
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The EM3E Master is an Education Programme supported by the European Commission, the European Membrane Society (EMS), the European Membrane House (EMH), and a large international network of industrial companies, research centers and universities
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The increasing environmental concern about waste materials and the necessity of improving the performance of asphalt mixtures prompted the study of incorporating different waste materials in conventional bitumen. The reuse of waste materials can present benefits at an environmental and economic level, and some wastes can be used to improve the pavement performance. Thus, the purpose of this study is to evaluate the incorporation of different waste materials in bitumen, namely waste motor oil and different polymers. In order to accomplish this goal, 10% of waste motor oil and 5% of polymers (high density polyethylene, crumb rubber and styrene-butadiene-styrene) were added to a conventional bitumen and the resulting modified bitumens were characterized through basic and rheological tests. From this work, it can be concluded that the incorporation of different waste materials improve some important properties of the conventional bitumen. Such improvements might indicate a good behaviour at medium/high temperatures and an increase of fatigue and rutting resistance. Therefore, these modified bitumens with waste materials can contribute to a sustainable development of road paving industry due to their performance and environmental advantages.
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The last decade has witnessed an increased research effort on multi-phase magnetoelectric (ME) composites. In this scope, this paper presents the application of novel materials for the development of anisotropic magnetoelectric (ME) sensors based on δ-FeO(OH)/P(VDF-TrFE) composites. The composite is able to precisely determine the amplitude and direction of the magnetic field. A new ME effect is reported in this study, as it emerges from the magnetic rotation of the δ-FeO(OH) nanosheets inside the piezoelectric P(VDF-TrFE) polymer matrix. δ-FeO(OH)/P(VDF-TrFE) composites with 1, 5, 10 and 20 δ-FeO(OH) filler weigh percentage in three δ-FeO(OH) alignment states (random, transversal and longitudinal) have been developed. Results shown that the modulus of the piezoelectric response (10-24 pC.N-1) is stable at least up to three months, the shape and magnetization maximum value (3 emu.g-1) is dependent on δ-FeO(OH) content and the obtained ME voltage coefficient, with a maximum of ≈0.4 mV.cm-1.Oe-1, is dependent on the incident magnetic field direction and intensity. In this way, the produced materials are suitable for innovative anisotropic sensor and actuator applications.
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Cancer cells rely mostly on glycolysis to meet their energetic demands, producing large amounts of lactate that are extruded to the tumour microenvironment by monocarboxylate transporters (MCTs). The role of MCTs in the survival of colorectal cancer (CRC) cells is scarce and poorly understood. In this study, we aimed to better understand this issue and exploit these transporters as novel therapeutic targets alone or in combination with the CRC classical chemotherapeutic drug 5-Fluorouracil. For that purpose, we characterized the effects of MCT activity inhibition in normal and CRC derived cell lines and assessed the effect of MCT inhibition in combination with 5-FU. Here, we demonstrated that MCT inhibition using CHC (a-cyano-4-hydroxycinnamic acid), DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid) and quercetin decreased cell viability, disrupted the glycolytic phenotype, inhibited proliferation and enhanced cell death in CRC cells. These results were confirmed by specific inhibition of MCT1/4 by RNA interference. Notably, we showed that 5-FU cytotoxicity was potentiated by lactate transport inhibition in CRC cells, either by activity inhibition or expression silencing. These findings provide novel evidence for the pivotal role of MCTs in CRC maintenance and survival, as well as for the use of these transporters as potential new therapeutic targets in combination with CRC conventional therapy.
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Fluorescence in situ hybridization (FISH) is a molecular technique widely used for the detection and characterization of microbial populations. FISH is affected by a wide variety of abiotic and biotic variables and the way they interact with each other. This is translated into a wide variability of FISH procedures found in the literature. The aim of this work is to systematically study the effects of pH, dextran sulfate and probe concentration in the FISH protocol, using a general peptide nucleic acid (PNA) probe for the Eubacteria domain. For this, response surface methodology was used to optimize these 3 PNA-FISH parameters for Gram-negative (Escherichia coli and Pseudomonas fluorescens) and Gram-positive species (Listeria innocua, Staphylococcus epidermidis and Bacillus cereus). The obtained results show that a probe concentration higher than 300 nM is favorable for both groups. Interestingly, a clear distinction between the two groups regarding the optimal pH and dextran sulfate concentration was found: a high pH (approx. 10), combined with lower dextran sulfate concentration (approx. 2% [w/v]) for Gram-negative species and near-neutral pH (approx. 8), together with higher dextran sulfate concentrations (approx. 10% [w/v]) for Gram-positive species. This behavior seems to result from an interplay between pH and dextran sulfate and their ability to influence probe concentration and diffusion towards the rRNA target. This study shows that, for an optimum hybridization protocol, dextran sulfate and pH should be adjusted according to the target bacteria.
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Rationale: Aging adults represent the fastest growing population segment in many countries. Physiological and metabolic changes in the aging process may alter how aging adults respond to exposures compared to younger workers. Current preventive workplace exposure measures may therefore not be sufficiently protective for the aging workforce. In a controlled human toxicokinetic study (exposure chamber; 12m3), the volunteers (n=11) were men and women over the age of 58 years and exposed to a commonly used, low neurotoxic glycol ether; PGME (CAS no. 107-98- 2) (50 ppm, 6 hours). Oxidative metabolism (Michaelis-Menten) is the major pathway and conjugation the minor in humans. Metabolites, conjugated and free PGME are eliminated through the kidneys, and the elimination kinetics is dose-dependent (0 order). Scope: (1) compare the toxicokinetic profile of PGME obtained in the aging volunteers (58- 62 years) to young volunteers (20-25 years) from a previous study; (2) Test the predictive power of an existing PGME toxicokinetic compartment model for aging persons against urinary PGME concentrations found in volunteers from our experimental study. Experimental procedure: Urine samples were collected before, every 2-hour during exposures for six hours, and ad-lib for additional 20 hours. Urinary analysis of free and total PGME was performed using capillary GC/FID. The toxicokinetic model (Berkley Madonna software) was ageadjusted. Results. Urinary free and total PGME concentration rose rapidly, and did not reach an apparent plateau level during exposure. Less conjugation was observed in the older group. The predictive model developed for the young group predicted well total PGME in the aging group but not free PGME. The age adjusted toxicokinetic model's Vmax1 had to be changed for the aging group, implying slower enzymatic pathway. Conclusion: The toxicokinetic model did not predict well if only the physiological parameters were adjusted for aging adults (existing model); a substance specific metabolic rate parameter was also needed.
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The objective of this paper is to explore the relative importance of each of Marshall's agglomeration mechanisms by examining the location of new manufacturing firms in Spain. In particular, we estimate the count of new firms by industry and location as a function of (pre-determined) local employment levels in industries that: 1) use similar workers (labor market pooling); 2) have a customer- supplier relationship (input sharing); and 3) use similar technologies (knowledge spillovers). We examine the variation in the creation of new firms across cities and across municipalities within large cities to shed light on the geographical scope of each of the three agglomeration mechanisms. We find evidence of all three agglomeration mechanisms, although their incidence differs depending on the geographical scale of the analysis.
Resumo:
The objective of this paper is to explore the relative importance of each of Marshall's agglomeration mechanisms by examining the location of new manufacturing firms in Spain. In particular, we estimate the count of new firms by industry and location as a function of (pre-determined) local employment levels in industries that: 1) use similar workers (labor market pooling); 2) have a customer- supplier relationship (input sharing); and 3) use similar technologies (knowledge spillovers). We examine the variation in the creation of new firms across cities and across municipalities within large cities to shed light on the geographical scope of each of the three agglomeration mechanisms. We find evidence of all three agglomeration mechanisms, although their incidence differs depending on the geographical scale of the analysis.
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The thesis interprets the caveat of Article 194(2) TFEU in order to assess the use of the Article as a legal basis for energy provisions provided by the European Union. The research subject is the Energy Title in the Treaty of the Functioning of the European Union and the possibilities of the application of the legal basis provided therein. The purpose is analysis of the possibilities for providing of provisions within the scope of the caveat found in Article 194(2) TFEU with special regard to the possibilities of providing renewable energy legislation. The purpose of the thesis is on one hand to provide an overview of the premises for providing of energy provisions in the EU, and on the other hand to analyse the Treaty text in order to determine the legal basis for energy provisions. The ultimate objective is to determine the correct legal basis for renewable energy provisions, aimed at the mitigation of climate change. According to Article 194(2) TFEU, the practice of the shared legislative powers in the field of energy are restricted by the retention of certain energy matters within the power of the Member States. The wording of the caveat containing the restrictions is open to interpretation and has been a subject of extensive discussion. Many scholars have argued that the caveat in Article 194(2) TFEU might obstruct decision-making in energy matters. This argument is contested, and the factual impact of the codification of the energy competences is analysed. The correct legal basis for energy provisions depends on the final interpretation of the text of the caveat and the level of significance of the effect of the measure. The use of Article 194(2) TFEU as a legal basis might not be the only option. There is a possibility that the legal bases within the Environmental Title might be used as legal bases for energy provisions in addition to Article 194(2) TFEU.
Resumo:
The thesis interprets the caveat of Article 194(2) TFEU in order to assess the use of the Article as a legal basis for energy provisions provided by the European Union. The research subject is the Energy Title in the Treaty of the Functioning of the European Union and the possibilities of the application of the legal basis provided therein. The purpose is analysis of the possibilities for providing of provisions within the scope of the caveat found in Article 194(2) TFEU with special regard to the possibilities of providing renewable energy legislation. The purpose of the thesis is on one hand to provide an overview of the premises for providing of energy provisions in the EU, and on the other hand to analyse the Treaty text in order to determine the legal basis for energy provisions. The ultimate objective is to determine the correct legal basis for renewable energy provisions, aimed at the mitigation of climate change. According to Article 194(2) TFEU, the practice of the shared legislative powers in the field of energy are restricted by the retention of certain energy matters within the power of the Member States. The wording of the caveat containing the restrictions is open to interpretation and has been a subject of extensive discussion. Many scholars have argued that the caveat in Article 194(2) TFEU might obstruct decision-making in energy matters. This argument is contested, and the factual impact of the codification of the energy competences is analysed. The correct legal basis for energy provisions depends on the final interpretation of the text of the caveat and the level of significance of the effect of the measure. The use of Article 194(2) TFEU as a legal basis might not be the only option. There is a possibility that the legal bases within the Environmental Title might be used as legal bases for energy provisions in addition to Article 194(2) TFEU.