490 resultados para ASYMMETRIES
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A tanulmányban a szerzők arra a kérdésre keresik a választ, hogy az aszimmetrikus információk hatására a vállalkozók és a befektetők között kialakuló megbízó-ügynök viszonynak melyek a speciális vetületei a kockázatitőke-finanszírozás vonatkozásában. A szerzők arra a következtetésre jutottak, hogy a hiányos információk, a megbízó-ügynök viszony, illetve az ügyletek speciális jellege miatt fokozottan jelentkező ügynökprobléma kezelésére a kockázatitőke-finanszírozás szereplői speciális kockázatkezelési technikákat alkalmaznak. Ilyenek a magas elvárt hozamok, a szigorú kiválasztási kritériumok, a speciális befektetési vagy szindikátusi szerződések, a befektetést követő monitoring tevékenység, a több lépcsőben történő finanszírozás és a portfólióvállalatok hálózatba szervezése. A speciális kockázati megközelítés következtében a befektetéseket opciós szemlélet is áthatja. _____ This paper focuses on the special aspects of imperfect information in case of venture capital financing including principal-agent relationship between entrepreneurs and investors as well as adverse selection that evolves as a result of information asymmetries. The authors’ finding is that venture capital is able to manage the problems caused by imperfect information via applying divers risk management techniques such as high profit expectations, scrutiny of portfolio-companies, the use of special contracting stipulations and syndicate agreements, the monitoring of investments, multi-staged financing of companies and the integration of portfolio-companies into networks. In addition to the risk management techniques the authors also give the interpretation of the unique attitude of venture capital toward uncertainty and its special real option-like risk valuation approach that makes venture capitalists capable of handling high uncertainty under imperfect information.
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This dissertation examines one category of international capital flows, private portfolio investments (private refers to the source of capital). There is an overall lack of a coherent and consistent definition of foreign portfolio investment. We clarify these definitional issues.^ Two main questions that pertain to private foreign portfolio investments (FPI) are explored. The first problem is the phenomenon of home preference, often referred to as home bias. Related to this are the observed cross-investment flows between countries that seem to contradict the textbook rendition of private FPI. A description of the theories purporting to resolve the home preference puzzle (and the cross-investment one) are summarized and evaluated. Most of this literature considers investors from major developed countries. I consider--as well--whether investors in less developed countries have home preference.^ The dissertation shows that home preference is indeed pervasive and profound across countries, in both developed and emerging markets. For the U.S., I examine home bias in both equity and bond holdings as well. I find that home bias is greater when we look at equity and bond holdings than equity holdings solely.^ In this dissertation a model is developed to explain home bias. This model is original and fills a gap in the literature as there have been no satisfactory models that handle at the same time both home preference and cross-border holdings in the context of information asymmetries. This model reflects what we see in the data and permits us to reach certain results by the use of comparative statics methods. The model suggests, counter-intuitively, that as the rate of return in a country relative to the world rate of return increases, home preference decreases. In the context of our relatively simple model we ascribe this result to the higher variance of the now higher return for home assets. We also find, this time as intended, that as risk aversion increases, investors diversify further so that home preference decreases.^ The second question that the dissertation deals with is the volatility of private foreign portfolio investment. Countries that are recipients of these flows have been wary of such flows because of their perceived volatility. Often the contrast is made with the perceived absence of volatility in foreign direct investment flows. I analyze the validity of these concerns using first net flow data and then gross flow data. The results show that FPI is not, in relative terms, more volatile than other flows in our sample of eight countries (half were developed countries and the rest were emerging markets).^ The implication therefore is that restricting FPI flows may be harmful in the sense that private capital may not be allocated efficiently worldwide to the detriment of capital poor economies. More to the point, any such restrictions would in fact be misguided. ^
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The investigation analyze s the role of the municipalities in the ongoing development of literacy teachers, having as a field of study the municipalities of Jaguaruana and Palhano, both in the State of Ceará. The political - educational space adopted as a sample of the study is the p eriod between the years 2003 and 2006, when the emphasis on cooperative action among the federated entities is observed in the Government’s guidelines and Brazilian educational policies, showing the municipal presence in the implementation and execution of these policies. T he historical - dialectical materialistic perspective, understood as an analysis of the social reality as historical elaboration and product of the human praxis, is expressed as the required theoretical - methodological path. The investigatio n is operationalized through interconnected stages: one that involves bibliographical and documental analysis, in which the theoretical input of the research is added, as well as the Federal, State and M unicipal documents accessed ; and another, regarding t he field work, studying the specific character of the object and its mutual rela tionships in the municipalities . The research brings the notion of intergovernmental relationships and cooperative mechanisms as central theoretical tools and, dialoguing with them, ideas such as decentralization, municipalization and municipal autonomy are inserted into a theoretical/practical body, through which the historical and logical aspects of the object are detailed. The study describes and interprets the policies of on going development of literacy teachers with focus on the national guidelines formulated since the 1990’s and on the govern mental incorporation in the national and subnational spaces. In this sense, the analysis is based on the comprehension of the interrel ationship between the municipal policies and the p olicies created by the S tate or Federal G overnments in order to offer ongoing development of literacy teachers. Considering the investigated sample, it shows how the municipal role and the relationships bet ween the State and municipalities of Ceará have emerged, as well as their characteristics regarding the education management policies, taking into account the practices of municipalization and cooperation between the State and municipalities in their histo rical composition. It shows the practices which aim at the ongoing development of literacy teachers observed in the researched municipalities, pointing out the realities and specific marks left by municipal presence in the area, demonstrating the assigned role and the role played. Based on the points of view of the managers interviewed in the municipalities of Jaguaruana e Palhano, it is possible to note the meaning and effectiveness of the policies carried out. With such elements, it discusses the municipa l asymmetries in their homogeneities and heterogeneities rega rding the execution of their federative role. The analysis shows that th e role of the municipalities vary according to the historical, political and social interventions in each municipality. In the fields of formulation and execution of educational policies, the actions of the municipal governments, situated and with expressive interferences, reveal asymmetries in the sense that some municipalities have bigger autonomy and participate more effect ively in the production and distribution of policies than others. In terms of the researched realities, the study shows that taking care of the policies of ongoing development of literacy teachers is not a task that should be assigned exclusively to the mu nicipalities, nonetheless it is a role that they play with varying degrees of success. This role is in fact a joint competence of the federated entities, in the scope the Brazilian cooperative federalism.
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In the Brazilian network of psychosocial care, health professionals are important actors in the process of transformation of mental health public policies among various services. In the reality of psychiatric hospitals, one should understand the need to expand the debate about the current context of practices developed. This study aimed at analyzing the process of psychiatric reform and the mental health policy in the State of Rio Grande do Norte (RN) from the profiles and practices of higher-level professionals in two psychiatric hospitals. This is a cross-sectional and descriptive research, with quantitative and qualitative data, conducted in two psychiatric hospitals of RN. The universe of the target population was 95 professionals, taking into account the margin of error of 8%, non-response rate and the inclusion criteria: holding effective link with the institution by means of approval in public examination for, at least, six months, being state or municipal servant; having a minimum weekly workload of 20 hours in service; participating in care and/or activities with patients and families in a direct way. The final sample consisted of 60 professionals. The tool for data collection was a questionnaire with closed and semi-open questions about socioeconomic profile, and mental health policies, practices and training. Quantitative data were tabulated in the statistical software SPSS, and simple and bivariate statistics, chi-square type, was used for analysis by adopting the significance level with the value p<0,05. In order to analyze data, the content analysis of Bardin was used. The qualitative findings obtained with the semi-open questions in Analyse Lexicale par Context d'un Ensemble de Segments de Texte (ALCESTE) were grouped into four thematic axes: Professional action in mental health; Mental health training; Scenarios of psychiatric reform and psychiatric hospitals; Mental health policies and practices: challenges for professionals in hospitals. The profile of professionals has revealed the majority of women (89,7%), nurses (36,7%), aged 50-59 years (42,9%), weekly workload of 40 hours (52,4% ), time of completion of graduation from six to 15 years (57%), and 21,4% reported to have specialization in mental health. Regarding the practices developed in individual care, it was found an association between those who do not build or partially conducts the therapeutic project and those who conduct care related to observation and annotation. In family care, it was obtained care consultation during crisis; and, in group care, recreational activities. In the analysis of thematic axes, it was noted that, despite changes identified in the profiles and practices of higher-level professionals in care services for mental health, with the implementation of new public policies for this field, the findings indicate the confluence of asymmetries and divergences in the actions of the teams in psychiatric hospitals, difficulties in managing services, frequent readmissions, reduced quantitative of available services and equipment, high demand of users, disarticulation of the network of psychosocial care, and the very shortage of skilled human resources to compose these services. Accordingly, the evidenced scenarios partially outline the current political and ideological mismatch of the national process of psychiatric reform that denies the role of care actions conducted within hospitals, although it has not gone far enough with the creation of new services that justify the total extinction of this institution
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This paper examines the formal features, the political rationale, distinctiveness, potential, and difficulties of post-liberal regionalism, with a particular focus on the case of UNASUR. Through this organization, traditional unionism and aspirations of Latin American regional integration are redefined in a South American geographic and ideational framework. Through this strategy South America became a political and economic construct in order to respond to globalization challenges and to achieve its members’ goals in development, regional autonomy (particularly in regards to the US), international influence and at the same time domestic governance of the involved countries. Nevertheless, the limits of this project’s future are being defined by nationalism, traditional visions of sovereignty and by a regional construction that involve significant institutional limitations, which are product of its intergovernmental logic, internal asymmetries and ambivalent Brazilian leadership
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The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30-80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy-corrected for geometrical effects-is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.
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Background: There is growing evidence that individual EEG differences may aid in classifying patients with major depressive disorder (MDD) and also help predict clinical response to antidepressant treatment. This study aims to compare the effectiveness of EEG frequency band power, alpha asymmetry and prefrontal theta cordance towards escitalopram response prediction and MDD diagnosis, in a multi-site initiative. Methods: Resting EEG (eyes open and closed) was recorded from 64 electrodes in 44 depressed patients and 20 healthy controls at baseline, 2 weeks post-treatment and 8 weeks post-treatment. Clinical response was measured as change from baseline MADRS of 50% or more. EEG measures were analyzed (1) at baseline (2) at 2 weeks post-treatment and (3) as an ‘‘early change” variable defined as change in EEG from baseline to 2 weeks post-treatment. Results: At baseline, responders exhibited greater absolute alpha power in the left hemisphere versus the right while non-responders showed the opposite. Responders further exhibited a cortical asymmetry of greater right relative to left activity in parietal areas. Groups also differed in baseline relative delta power with responders showing greater power in the right hemisphere versus the left while non-responders showed the opposite. At 2 weeks post-treatment, responders exhibited greater absolute beta power in the left hemisphere relative to right and the opposite was noted for non-responders. The opposite pattern was noted for absolute and relative delta power at 2 weeks post-treatment. Responders exhibited early reduction in relative alpha power and early increments in relative theta power. Non-responders showed a significant early increase in prefrontal theta cordance. Absolute delta power helped distinguish MDD patients from healthy controls. Conclusions: Hemispheric asymmetries in the alpha and delta bands at pre-treatment baseline and at 2 weeks post-treatment have moderate to moderately strong predictive utility towards antidepressant treatment response. These findings have significant potential for improving clinical practice in psychiatry by eventually guiding clinical choice of treatments. This would greatly benefit patients awaiting relief from depressive symptoms as treatment optimization would help overcome problems associated with delayed recovery. Our results also indicate that resting EEG activity may have clinical utility in predicting MDD diagnosis.
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Poverty (low income) dynamics are explored using tax filer data covering the period 1992 to 1996. The distributions of short-and long-term episodes are identified, and reveal substantial differences by sex and family type. Entry and exit models explore the relationships between poverty transitions and sex, family status and other personal and situational attributes. Duration effects on exiting and re-entering poverty are found to be important, and models including past poverty experiences point to strong "occurrence dependence" for poverty entry and incidence. Fixed-effect panel data models confirm the above, and reveal asymmetries in the impacts of household transitions on poverty.
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This article considers the opportunities of civilians to peacefully resist violent conflicts or civil wars. The argument developed here is based on a field-based research on the peace community San José de Apartadó in Colombia. The analytical and theoretical framework, which delimits the use of the term ‘resistance’ in this article, builds on the conceptual considerations of Hollander and Einwohner (2004) and on the theoretical concept of ‘rightful resistance’ developed by O’Brien (1996). Beginning with a conflict-analytical classification of the case study, we will describe the long-term socio-historical processes and the organizational experiences of the civilian population, which favoured the emergence of this resistance initiative. The analytical approach to the dimensions and aims of the resistance of this peace community leads to the differentiation of O`Brian’s concept of ‘rightful resistance’.
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Este editorial establece las coordenadas de contenido del presente monográfico donde se sugieren dos rutas de lectura y formas posibles de desplazamiento. Una de éstas rutas muestra las asimetrías, las formas de exclusión y al mismo tiempo las formas de apropiación de las tecnologías desde América Latina y España. La segunda opta por trabajos provocadores que sugieren nuevas metáforas y aproximaciones conceptuales para repensar la contemporaneidad.
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The violent merger of two carbon-oxygen white dwarfs has been proposed as a viable progenitor for some Type Ia supernovae. However, it has been argued that the strong ejecta asymmetries produced by this model might be inconsistent with the low degree of polarization typically observed in Type Ia supernova explosions. Here, we test this claim by carrying out a spectropolarimetric analysis for the model proposed by Pakmor et al. for an explosion triggered during the merger of a 1.1 and 0.9 M⊙ carbon-oxygen white dwarf binary system. Owing to the asymmetries of the ejecta, the polarization signal varies significantly with viewing angle. We find that polarization levels for observers in the equatorial plane are modest (≲1 per cent) and show clear evidence for a dominant axis, as a consequence of the ejecta symmetry about the orbital plane. In contrast, orientations out of the plane are associated with higher degrees of polarization and departures from a dominant axis. While the particular model studied here gives a good match to highly polarized events such as SN 2004dt, it has difficulties in reproducing the low polarization levels commonly observed in normal Type Ia supernovae. Specifically, we find that significant asymmetries in the element distribution result in a wealth of strong polarization features that are not observed in the majority of currently available spectropolarimetric data of Type Ia supernovae. Future studies will map out the parameter space of the merger scenario to investigate if alternative models can provide better agreement with observations.
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Extremely broad emission wings at Hβ and Hα have been found in VLT-FLAMES Tarantula Survey data for five very luminous BA supergiants in or near 30 Doradus in the Large Magellanic Cloud. The profiles of both lines are extremely asymmetrical, which we have found to be caused by very broad diffuse interstellar bands (DIBs) in the longward wing of Hβ and the shortward wing of Hα. These DIBs are well known to interstellar but not to many stellar specialists, so that the asymmetries may be mistaken for intrinsic features. The broad emission wings are generally ascribed to electron scattering, although we note difficulties for that interpretation in some objects. Such profiles are known in some Galactic hyper/supergiants and are also seen in both active and quiescent Luminous Blue Variables (LBVs). No prior or current LBV activity is known in these 30 Dor stars, although a generic relationship to LBVs is not excluded; subject to further observational and theoretical investigation, it is possible that these very luminous supergiants are approaching the LBV stage for the first time. Their locations in the HRD and presumed evolutionary tracks are consistent with that possibility. The available evidence for spectroscopic variations of these objects is reviewed, while recent photometric monitoring does not reveal variability. A search for circumstellar nebulae has been conducted, with an indeterminate result for one of them.
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Understanding the population structure and patterns of gene flow within species is of fundamental importance to the study of evolution. In the fields of population and evolutionary genetics, measures of genetic differentiation are commonly used to gather this information. One potential caveat is that these measures assume gene flow to be symmetric. However, asymmetric gene flow is common in nature, especially in systems driven by physical processes such as wind or water currents. As information about levels of asymmetric gene flow among populations is essential for the correct interpretation of the distribution of contemporary genetic diversity within species, this should not be overlooked. To obtain information on asymmetric migration patterns from genetic data, complex models based on maximum-likelihood or Bayesian approaches generally need to be employed, often at great computational cost. Here, a new simpler and more efficient approach for understanding gene flow patterns is presented. This approach allows the estimation of directional components of genetic divergence between pairs of populations at low computational effort, using any of the classical or modern measures of genetic differentiation. These directional measures of genetic differentiation can further be used to calculate directional relative migration and to detect asymmetries in gene flow patterns. This can be done in a user-friendly web application called divMigrate-online introduced in this study. Using simulated data sets with known gene flow regimes, we demonstrate that the method is capable of resolving complex migration patterns under a range of study designs.
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Introdução: A lateralidade é a diferença na capacidade de controlo entre os dois lados do corpo. Os métodos utilizados para avaliar a lateralidade manual incluem a observação efetiva do uso do membro dominante ou a aplicação de inventários respondidos pelo próprio indivíduo avaliado. O Inventário de Lateralidade de Edinburgh (EHI) é o instrumento mais utilizado para avaliar a lateralidade manual. Apesar do seu uso amplo, em Portugal não existem estudos que avaliem a sua validade e fidedignidade. Objetivos: Estudar as propriedades psicométricas do Inventário de Lateralidade de Edinburgh numa amostra da população portuguesa. Métodos: A amostra é constituída por 290 pessoas (135 homens e 155 mulheres), com idades compreendidas entre os 18 e os 65 anos. Todos os participantes preencheram uma declaração de consentimento informado e uma bateria de testes neuropsicológicos Resultados: A média no EHI foi de 62,36 (DP = 38,00). Os resultados demonstraram que das seis variáveis sociodemográficas (idade, sexo, escolaridade, zona de residência, regiões e profissão) três apresentaram ter influência significativa nas pontuações do EHI: idade, zona de residência e regiões. A confiabilidade e a estabilidade temporal do EHI apresentaram resultados adequados. A análise fatorial confirmatória mostrou que o modelo não é melhor explicado por um fator. Para dois fatores o modelo continua a não ser adequado. Conclusão: Apesar de termos obtido uma boa consistência interna não nos é possível considerar este teste como o mais adequado para medir o constructo da lateralidade. / Introduction: The handedness is the difference in the control capacity between the two sides of the body. The methods used to evaluate the manual handedness include the effective observation of the use of dominant member or application of inventories answered by the person assessed. The Edinburgh Handedness Inventory (EHI) is the most used to evaluate manual handedness. Even though being widely used, in Portugal there are no studies that measure its validity and reliability. Objective: To study the psychometric properties of Edinburgh Handedness Inventory in a Portuguese sample. Methods: The sample consists of 290 people (135 men and 155 women), aged between 18 and 65 years. All participants filled an informed consent form and a battery of neuropsychological tests. Results: The average in EHI was 62.36 (SD = 38.00). The results showed that 3 of 6 sociodemographic variables showed significant influence in EHI scores. The reliability and temporal stability of EHI were adequate. Confirmatory factor analysis showed that the model is not better explained by one factor. A two-factor model was not also suitable. Conclusion: Even though we got a good internal consistency we cannot consider this test as the most appropriate for measuring the handedness construct.
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Thesis (Ph.D.)--University of Washington, 2016-08