890 resultados para Consistent transaction layer
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Mercados são instituições criadas para facilitar uma atividade de comercialização. Isto é possível porque um mercado é constituído por instituições que foram desenhadas para reduzir os custos de transação associados a este processo de troca. A partir dessas duas ideias, esta tese possui três objetivos principais. (i) Analisar por que a literatura de análise de cointegração tem mensurado estes custos de forma imprecisa. A principal razão é certa confusão entre os conceitos de custos de transação, de transporte e de comercialização. (ii) Propor um procedimento para mensurar indiretamente os custos de transação de mercado variáveis combinando os modelos de cointegração com mudança de regime e a estrutura teórica oferecidas pela Nova Economia Institucional. Este procedimento é aplicado para quantificar quanto custa comercializar etanol no mercado internacional usando suas atuais instituições. (iii) Por fim, usando os mesmos modelos e a mesma estrutura teórica, esta dissertação contesta a hipótese de que já existe um mercado internacional de etanol bem desenvolvido, tal qual a literatura tem assumido. De forma semelhante, também é avaliada a hipótese de que a remoção das barreiras comerciais norte-americanas para o etanol brasileiro seria uma condição suficiente para o desenvolvimento deste mercado internacional. Os testes aplicados rejeitam ambas as hipóteses.
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Transaction costs have a random component in the bid-ask spread. Facing a high bid-ask spread, the consumer has the option to wait for better terms oI' trade, but only by carrying an undesirable portfolio balance. We present the best policy in this case. We pose the control problem and show that the value function is the uni que viscosity solution of the relevant variational inequality. Next, a numerical procedure for the problem is presented.
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The heteroskedasticity-consistent covariance matrix estimator proposed by White (1980), also known as HC0, is commonly used in practical applications and is implemented into a number of statistical software. Cribari–Neto, Ferrari & Cordeiro (2000) have developed a bias-adjustment scheme that delivers bias-corrected White estimators. There are several variants of the original White estimator that also commonly used by practitioners. These include the HC1, HC2 and HC3 estimators, which have proven to have superior small-sample behavior relative to White’s estimator. This paper defines a general bias-correction mechamism that can be applied not only to White’s estimator, but to variants of this estimator as well, such as HC1, HC2 and HC3. Numerical evidence on the usefulness of the proposed corrections is also presented. Overall, the results favor the sequence of improved HC2 estimators.
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Lucas (2000) estimates that the US welfare costs of inflation are around 1% of GDP. This measurement is consistent with a speci…c distorting channel in terms of the Bailey triangle under the demand for monetary base schedule (outside money): the displacement of resources from the production of consumption goods to the household transaction time à la Baumol. Here, we consider also several new types of distortions in the manufacturing and banking industries. Our new evidences show that both banks and firms demand special occupational employments to avoid the inflation tax. We de…ne the concept of ”the foat labor”: The occupational employments that are aflected by the in‡ation rates. More administrative workers are hired relatively to the bluecollar workers for producing consumption goods. This new phenomenon makes the manufacturing industry more roundabout. To take into account this new stylized fact and others, we redo at same time both ”The model 5: A Banking Sector -2” formulated by Lucas (1993) and ”The Competitive Banking System” proposed by Yoshino (1993). This modelling allows us to characterize better the new types of misallocations. We …nd that the maximum value of the resources wasted by the US economy happened in the years 1980-81, after the 2nd oil shock. In these years, we estimate the excess resources that are allocated for every speci…c distorting channel: i) The US commercial banks spent additional resources of around 2% of GDP; ii) For the purpose of the firm foating time were used between 2.4% and 4.1% of GDP); and iii) For the household transaction time were allocated between 3.1% and 4.5 % of GDP. The Bailey triangle under the demand for the monetary base schedule represented around 1% of GDP, which is consistent with Lucas (2000). We estimate that the US total welfare costs of in‡ation were around 10% of GDP in terms of the consumption goods foregone. The big di¤erence between our results and Lucas (2000) are mainly due to the Harberger triangle in the market for loans (inside money) which makes part of the household transaction time, of the …rm ‡oat labor and of the distortion in the banking industry. This triangle arises due to the widening interest rates spread in the presence of a distorting inflation tax and under a fractionally reserve system. The Harberger triangle can represent 80% of the total welfare costs of inflation while the remaining percentage is split almost equally between the Bailey triangle and the resources used for the bank services. Finally, we formulate several theorems in terms of the optimal nonneutral monetary policy so as to compare with the classical monetary theory.
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The intent of this paper is to provide a practitioners insight into the present and foreseeable future of problem of transaction cost economics related to culture and business etiquette that may increase the of complexity of business communication. We will also explore whether it impacts participant's mindsets regarding opportunistic or passive aggressive behavior. We will study the role of culture, ethics, information asymmetry, and legal systems regarding their importance towards the business contracts and lack of knowledge in local environments. We will make connections to contract theory strategies and objectives and recommend business practices. Furthermore, economic theory explores the role of the impossibility of the perfect contract. Historical and present day operational factors are examined for the determination of forward-looking contract law indications worldwide. This paper is intended provide a practitioners view with a global perspective of a multinational, mid-sized and small corporations giving consideration in a non-partisan and non-nationalistic view, yet examines the individual characteristics of the operational necessities and obligations of any corporation. The study will be general, yet cite specific articles to each argument and give adequate consideration to the intricacies of the global asymmetry of information. This paper defends that corporations of any kind and size should be aware of the risk of international business etiquette and cultural barriers that might jeopardize the savings you could obtain from engaging international suppliers.
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As organizações são alvos constantes de mudanças impostas por fatores que exigem rápidas e consistentes decisões para se manterem competitivas. A estratégia que melhor explora os recursos e as competências como forma de obtenção de vantagens competitivas sustentáveis pode estar dentro ou fora das fronteiras organizacionais. Este trabalho tem como objetivo identificar e avaliar as razões que levaram uma indústria de bebidas à migração de um modelo de distribuição terceirizado para um verticalmente integrado. Para tal, foi realizado um estudo de caso que permitiu avaliar o comportamento dos transportadores na ótica do contratante, e o processo de análise e implementação desse projeto de verticalização. Com os resultados obtidos foi possível avaliar as vantagens e riscos desse novo modelo, explorando o cruzamento entre as contribuições teóricas e empíricas. Portanto, ampliamos a visão da academia e dos executivos sobre a decisão de sourcing, e exploramos os aspectos estratégicos desse complexo e importante processo decisório.
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This present study analyses the Regulation on Chemicals of the European Union – so called REACH, and some of its main features. Technical barriers to trade have become the new instrument of distorting international trade benefits and creating protection for domestic industry, on the basis of protection of human health and the environment. It aims at identifying REACH’s most primary and controversial element and its consistency under the World Trade Organization System, in context of the Agreement on Technical Barriers to Trade
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Tissue engineering is an important branch of regenerative medicine that uses cells, materials (scaffolds), and suitable biochemical and physicochemical factors to improve or replace specific biological functions. In particular, the control of cell behavior (namely, of cell adhesion, proliferation and differentiation) is a key aspect for the design of successful therapeutical approaches. In this study, poly(lactic-co-glycolic acid) (PLGA) fiber mats were prepared using the electrospinning technology (the fiber diameters were in the micrometer range). Furthermore, the electrospun fiber mats thus formed were functionalized using the layer-by- layer (LbL) technique with chitosan and alginate (natural and biodegradable polyelectrolytes having opposite charges) as a mean for the immobilization of pDNA/dendrimer complexes. The polyelectrolyte multilayer deposition was confirmed by fluorescence spectroscopy using fluorescent-labeled polyelectrolytes. The electrospun fiber mats coated with chitosan and alginate were successfully loaded with complexes of pDNA and poly(amidoamine) (PAMAM) dendrimers (generation 5) and were able of releasing them in a controlled manner along time. In addition, these mats supported the adhesion and proliferation of NIH 3T3 cells and of human mesenchymal stem cells (hMSCs) in their surface. Transfection experiments using a pDNA encoding for luciferase showed the ability of the electrospun fiber mats to efficiently serve as gene delivery systems. When a pDNA encoding for bone morphogenetic protein-2 (BMP-2) was used, the osteoblastic differentiation of hMSCs cultured on the surface of the mats was promoted. Taken together, the results revealed that merging the electrospinning technique with the LbL technique, can be a suitable methodology for the creation of biological active matrices for bone tissue engineering.
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To describe retinal nerve fiber layer changes in late-stage diffuse unilateral subacute neuroretinitis eyes and compare these results with healthy eyes observed through nerve fiber analyzer (GDx®). Methods: This is a retrospective case-control study in which 49 eyes in late-stage diffuse unilateral subacute neuroretinitis were examined from May/97 to December/ 01. First, eyes with diffuse unilateral subacute neuroretinitis and healthy contralateral eyes (Control Group I) were statistically matched. Subsequently, eyes with diffuse unilateral subacute neuroretinitis were compared with eyes of healthy patients (Control Group II). Results: Eyes from Control Groups I and II had higher relative frequency of “within normal limits” status. Eyes from the diffuse unilateral subacute neuroretinitis (DUSN) Group had higher frequency of “outside normal limits” and “borderline” status. Control Groups I and II had absolute values different from the DUSN Group regarding all parameters (p<0.05), except for Symmetry in Control Groups I and II, Average thickness and Superior Integral in control group II. Conclusion: Patients with late-stage diffuse unilateral subacute neuroretinitis presented presumed decrease in nerve fiber layer thickness shown by GDx®. Retinal zones with larger vascular support and larger amount of nerve fibers presented higher decrease in the delay of the reflected light measured by the nerve fiber analyzer
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The definition of the boundaries of the firms is subject that has occupied the organizational theorists long ago, being the seminal work of Coase (1937) indicated as the trigger for one theoretical evolution, with emphasis on governance structures, which led to a modern theory of incomplete contracts. The Transaction Cost Economics (TCE) and Agency Theory arise within this evolution, being widely used in studies related to the theme. Empirically, data envelopment analysis (DEA) has established itself as a suitable tool for analysis of efficiency. Although TCE argues that specific assets must be internalized, recent studies outside the mainstream of theory show that, often, firms may decide, for various reasons, hire them on the market. Researches on transaction costs face with the unavailability of information and methodological difficulties in measuring their critical variables. There`s still the need for further methodological deepening. The theoretical framework includes classic works of TCE and Agency Theory, but also more recent works, outside the mainstream of TCE, which warn about the existence of strategies in use of specific assets that aren`t necessarily aligned with the classical ideas of TCE. The Brazilian oil industry is the focus of this thesis, that aimed to evaluate the efficiency of contracts involving high specificity service outsourced by Petrobras. In order to this, we made the categorization of outsourced services in terms of specificity, as well the description of services with higher specificity. Then, we verified the existence of relationship between the specificity of services and a number of variables, being found divergent results than those that are preached by the mainstream of TCE. Then, we designed a DEA model to analyze the efficiency in the use of onshore drilling rigs, identified among the services of highest specificity. The next step was the application of the model to evaluate the performance of drilling rigs contracts. Finally, we verified the existence of relationship between the efficiency of contracts and a number of variables, being found, again, results not consistent with the theory mainstream. Regarding to analyze of efficiency of drilling rigs contracts, the model developed is compatible with what is found in academic productions in efficiency of drilling rigs. The results on efficiency show a wide range of scores, with efficiencies ranging from 31.79% to 100%, being low the sample efficiency average. There is consonance between the model results and the practices adopted by Petrobras. The results strengthen the DEA as an important tool in studies of efficiency with possibility to use for analysis other types of contracts. In terms of theoretical findings, the results reinforce the arguments that there are situations in which the strategies of the organizations, in terms of use of assets and services of high specificity, do not necessarily follow what is recommended by the mainstream of TCE
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In this paper artificial neural network (ANN) based on supervised and unsupervised algorithms were investigated for use in the study of rheological parameters of solid pharmaceutical excipients, in order to develop computational tools for manufacturing solid dosage forms. Among four supervised neural networks investigated, the best learning performance was achieved by a feedfoward multilayer perceptron whose architectures was composed by eight neurons in the input layer, sixteen neurons in the hidden layer and one neuron in the output layer. Learning and predictive performance relative to repose angle was poor while to Carr index and Hausner ratio (CI and HR, respectively) showed very good fitting capacity and learning, therefore HR and CI were considered suitable descriptors for the next stage of development of supervised ANNs. Clustering capacity was evaluated for five unsupervised strategies. Network based on purely unsupervised competitive strategies, classic "Winner-Take-All", "Frequency-Sensitive Competitive Learning" and "Rival-Penalize Competitive Learning" (WTA, FSCL and RPCL, respectively) were able to perform clustering from database, however this classification was very poor, showing severe classification errors by grouping data with conflicting properties into the same cluster or even the same neuron. On the other hand it could not be established what was the criteria adopted by the neural network for those clustering. Self-Organizing Maps (SOM) and Neural Gas (NG) networks showed better clustering capacity. Both have recognized the two major groupings of data corresponding to lactose (LAC) and cellulose (CEL). However, SOM showed some errors in classify data from minority excipients, magnesium stearate (EMG) , talc (TLC) and attapulgite (ATP). NG network in turn performed a very consistent classification of data and solve the misclassification of SOM, being the most appropriate network for classifying data of the study. The use of NG network in pharmaceutical technology was still unpublished. NG therefore has great potential for use in the development of software for use in automated classification systems of pharmaceutical powders and as a new tool for mining and clustering data in drug development
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The protective effect of various Salmonella vaccines regimens against an experimental Salmonella Gallinarum challenge (SGNalr strain at 12 wk of age) was evaluated in two experiments. In Experiment 1 commercial brown layers were vaccinated according to one of the following programs: (i) two doses of a SE bacterin (Layermune SE; group 1); (ii) a first dose of a live SG9R vaccine (Cevac SG9R) followed by a SE bacterin (Layermune SE; group 2); (iii) one dose of each of two different multivalent inactivated vaccines containing SE cells (Corymune 4 & Corymune 7; group 3) or (iv) not vaccinated (group 4). In Experiment 2, broiler breeders were given the same vaccination treatments except for the group vaccinated with the multivalent vaccines. Overall, in both experiments, all vaccination schemes were effective in reducing mortality after challenge with a SG field strain. Primary vaccination with an initial dose of a live SG9R vaccine followed some weeks later by a dose of an inactivated SE bacterin was the most effective (p<0.05) vaccination program against mortality induced by field SG experimental challenge in both experiments. In conclusion, Salmonella vaccination programs containing SE bacterins alone or in combination with a live SG9R vaccine are effective in preventing mortality induced by infection of field SG. Nevertheless, it is important to emphasize that any vaccination program against any Salmonella serotype will only be effective if it is part of a sound and comprehensive biosecurity program designed for Salmonella control in poultry farms.
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Two experiments were performed to evaluate the protective effect of various vaccination combinations given at 5 and 9 weeks of age against experimental challenge with Salmonella enterica serovar Enteritidis ( SE) phage type 4 at 12 weeks of age. In Experiment 1, groups of commercial layers were vaccinated by one of the following programmes: Group 1, two doses of a SE bacterin (Layermune SE); Group 2, one dose of a live Salmonella enterica serovar Gallinarum vaccine (Cevac SG9R) followed by one dose of the SE bacterin; Group 3, one dose of each of two different multivalent inactivated vaccines containing SE cells (Corymune 4K and Corymune 7K; and Group 4, unvaccinated, challenged controls. In Experiment 2, groups of broiler breeders were vaccinated by the same programmes as Groups 1 and 2 above while Group 3 was an unvaccinated, challenged control group. All vaccination programmes and the challenge induced significant (P<0.05) seroconversion as measured by enzyme-linked immunosorbent assay. Overall, in both experiments, all vaccination schemes were significantly effective in reducing organ (spleen, liver and caeca) colonization by the challenge strain as well as reducing faecal excretion for at least 3 weeks. Vaccinated layers in Groups 1 and 2 and broiler breeders in Group 2 showed the greatest reduction in organ colonization and the least faecal excretion. In Experiment 1, layers vaccinated with multivalent inactivated vaccines containing a SE component (Group 3) were only moderately protected, indicating that such a vaccination programme may be useful in farms with good husbandry and housing conditions and low environmental infectious pressure by Salmonella.