Página 19 dos resultados de 2111 itens digitais encontrados em 0.022 segundos

## Interação entre política fiscal e monetária, independência do Banco Central e competição eleitoral : uma abordagem de Teoria dos Jogos

Umeno, Luis Gustavo
Tipo: Tese
POR
Relevância na Pesquisa
26.02%

## Origin of Asymmetric Charge Partitioning in the Dissociation of Gas-Phase Protein Homodimers

Jurchen, John C.; Williams, Evan R.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.09%
The origin of asymmetric charge and mass partitioning observed for gas-phase dissociation of multiply charged macromolecular complexes has been hotly debated. These experiments hold the potential to provide detailed information about the interactions between the macromolecules within the complex. Here, this unusual phenomenon of asymmetric charge partitioning is investigated for several protein homodimers. Asymmetric charge partitioning in these ions depends on a number of factors, including the internal energy, charge state, and gas-phase conformation of the complex, as well as the conformational flexibility of the protein monomer in the complex. High charge states of both cytochrome c and disulfide-reduced α-lactalbumin homodimers dissociate by a symmetrical charge partitioning process in which both fragment monomers carry away roughly an equal number of charges. In contrast, highly asymmetric charge partitioning dominates for the lower charge states. Cytochrome c dimer ions with eleven charges formed by electrospray ionization from two solutions in which the solution-phase conformation differs dissociate with dramatically different charge partitioning. These results demonstrate that these gas-phase complexes retain a clear “memory” of the solution from which they are formed...

## Direct and indirect roles for Nodal signaling in two axis conversions during asymmetric morphogenesis of the zebrafish heart

Baker, Kari; Holtzman, Nathalia G.; Burdine, Rebecca D.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
25.99%
The Nodal signaling pathway plays a conserved role in determining left-sided identity in vertebrates with this early left-right (L/R) patterning influencing the asymmetric development and placement of visceral organs. We have studied the role of Nodal signaling in asymmetric cardiac morphogenesis in zebrafish and describe two distinct rotations occurring within the heart. The first is driven by an asymmetric migration of myocardial cells during cardiac jogging, resulting in the conversion of the L/R axis to the dorsal-ventral (D/V) axis of the linear heart. This first rotation is directly influenced by the laterality of asymmetric gene expression. The second rotation occurs before cardiac looping and positions the original left cells exposed to Nodal signaling back to the left of the wild-type (WT) heart by 48 hours postfertilization (hpf). The direction of this second rotation is determined by the laterality of cardiac jogging and is not directly influenced by asymmetric gene expression. Finally, we have identified a role for Nodal signaling in biasing the location of the inner ventricular and outer atrial curvature formations. These results suggest that Nodal signaling directs asymmetric cardiac morphogenesis through establishing and subsequently reinforcing laterality information over the course of cardiac development.

## Comparative Transcriptional Analysis Reveals Differential Gene Expression between Asymmetric and Symmetric Zygotic Divisions in Tobacco

Hu, Tian-Xiang; Yu, Miao; Zhao, Jie
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26%
Asymmetric cell divisions occur widely during many developmental processes in plants. In most angiosperms, the first zygotic cell division is asymmetric resulting in two daughter cells of unequal size and with distinct fates. However, the critical molecular mechanisms regulating this division remain unknown. Previously we showed that treatment of tobacco zygotes with beta-glucosyl Yariv (βGlcY) could dramatically alter the first zygotic asymmetric division to produce symmetric two-celled proembryos. In the present study, we isolated zygotes and two-celled asymmetric proembryos in vivo by micromanipulation, and obtained symmetric, two-celled proembryos by in vitro cell cultures. Using suppression-subtractive hybridization (SSH) and macroarray analysis differential gene expression between the zygote and the asymmetric and symmetric two-celled proembryos was investigated. After sequencing of the differentially expressed clones, a total of 1610 EST clones representing 685 non-redundant transcripts were obtained. Gene ontology (GO) term analysis revealed that these transcripts include those involved in physiological processes such as response to stimulus, regulation of gene expression, and localization and formation of anatomical structures. A homology search against known genes from Arabidopsis indicated that some of the above transcripts are involved in asymmetric cell division and embryogenesis. Quantitative real-time PCR confirmed the up- or down-regulation of the selected candidate transcripts during zygotic division. A few of these transcripts were expressed exclusively in the zygote...

## Essays in Financial Economics

Kruger, Samuel Arthur
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
Relevância na Pesquisa
26.02%
This dissertation consists of three independent essays. Chapter 1, "The Effect of Mortgage Securitization on Foreclosure and Modification," assesses the impact of mortgage securitization on foreclosure and modification. My primary innovation is using the freeze of private mortgage securitization in the third quarter of 2007 to instrument for the probability that a loan is securitized. I find that privately securitized mortgages are substantially more likely to be foreclosed and less likely to be modified. Chapter 2, "Disagreement and Liquidity," analyzes how disagreement between investors affects the relationship between trading, liquidity, and asymmetric information. Traditional models predict that asymmetric information should destroy trade and liquidity. In contrast, I document empirical evidence that asymmetric information increases trading volumes in stock, corporate bond, and option markets. To resolve this puzzle, I propose a model of overconfident disagreement trading in which private information enhances trading and liquidity. Chapter 3, "Is Real Interest Rate Risk Priced? Theory and Empirical Evidence," asks whether investors demand compensation for holding assets whose returns covary with real interest rate shocks. Empirically...

## Three essays on consumer search behavior in experimental market environments.

Ke, Changxia
Relevância na Pesquisa
26.05%
This thesis investigates consumer search behavior in different contexts and its implications on certain market outcomes. It consists of three self-contained essays. Part one investigates if people search optimally and how price promotions (such as the provision of price discounts) influence search intensity and risk-taking behavior. We start with a typical sequential search task in a finite time horizon (with exogenously determined price dispersion) as the baseline treatment. In the two experimental treatments, exogenous discounts are introduced to the search process. The treatments differ in the amount of information on the discounts revealed to the subjects. Subjects’ search behavior is roughly consistent with optimality for a risk-neutral agent, but significantly influenced by the introduction of discount vouchers. We find that subjects’ search intensity is significantly reduced if they are in a shop that offers discounts, even when the monetary benefit induced by the discount has been taken into account. This suggests that people seem to gain extra non-monetary utility from buying a discounted product. Alternatively, subjects might overestimate the value of a discount. Following the findings in part one, we focus on price-framing effects of discounts on consumer search behavior in part two. In order to isolate the price-framing effect from all other possible influences...

## Cryptology Management in a Quantum Computing Era

Rosenberg, Nathanial Owen
Relevância na Pesquisa
26%
Todays most efficient and widely used cryptographic standards such as RSA rely on the difficulty of factoring large numbers to resist cryptanalysis. Asymmetric cryptography is used in a plethora of sensitive operations from online bank transactions to international e-commerce, and the Department of Defense also uses asymmetric cryptography to transmit sensitive data. Quantum computers have the potential to render obsolete widely deployed asymmetric ciphers essential to the secure transfer of information. Despite this, alternatives are not in place. The goal of this study is to understand the alternatives to classical asymmetric cryptography that can be used as substitutes should quantum computers be realized. This study explores quantum-resistant alternatives to traditional ciphers and involves experimenting with available implementations of ciphers described the post-quantum literature as well as developing our own implementations based on descriptions of algorithms in the literature. This study provides an original implementation of hash-based digital signature and detailed instructions on its use as well as customization of the NTRU lattice-based cryptography suite, including the use of NTRU and AES together in a hybrid cryptographic protocol. This thesis will make recommendations on future work necessary to prepare for the emergence of large-scale...

## Rapid Evolutionary Acquisition - an in-Progress Review of an Exemplar Pilot Initiative

Gunderson, Christopher R.; Minton, David H.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.04%
Chris Gunderson is a Research Associate at the Naval Postgraduate School. He is the principal investigator of the Open Enterprise Information System (OEIS) research initiative. This project sponsored by the Undersecretary of Defense for Intelligence and executed in the Northern Virginia. The project objective is to help the government improve its flawed information technology acquisition process through four key activities: Establish a collaborative network of government, industry, and academic experts who have succeeded at some aspect of OEIS; Study Internet successful stories and distill the lessons learned; Embed lessons learned into familiar government acquisition artifacts; Work with early adopting pilot projects to verify, validate, refine, and document best practices; Traditionally, the US military has sought and achieved asymmetric military advantage, i.e. delivered tactical blows, quickly, in the right places. However, lately, non-state terrorists have seized the asymmetric advantage. They use cutting edge Commercial-Off-the-Shelf Information Technology (COTS IT) for agile Command, Control, Communications, Computer and Intelligence (C4I). US Military, by contrast, is hamstrung by brittle, archaic MILSPEC C3I kit, and by a crushing bureaucracy that resists refreshing the technology at anything approaching Internet speeds. Members of the US Naval Intelligence have voluntarily reached across stovepipes to re-establish tactical asymmetric advantage...

## Essays on contests and conflicts

Yildizparlak, Anil
ENG
Relevância na Pesquisa
26.11%
My dissertation consists of three chapter that analyze of the behavior of decision makers and their interactions in situations where agents engage in costly effort investment in order to earn a prize such as property rights, natural resources, market shares, etc. This analysis allows competition between economic agents when the property rights are not clearly defined, imperfectly enforced, or absent completely by design or naturally. As property rights are absent in various economic environments, my dissertation allows applications of political economy, litigation, sports, etc. First chapter is a joint work with my supervisor Luis C. Corchón and it is a published work in Journal of Economic Behavior and Organization. Our paper concentrates on the Political Economy implications of contests and analyzes a conflict over a resource between two contestants that differ in effectiveness of employing their investments on forces. We consider, for the cases of complete and asymmetric information, a pre-existent resource distribution and we analyze the effects of that distribution on sustaining peace. We find that under complete information there is always some distribution that achieves peace. If the contestants are similar, the set of such distributions are larger. Thus...

## Essays on Decision Making with Information and Action Externalities

WANG, TAO
Fonte: Quens University Publicador: Quens University
EN; EN
Relevância na Pesquisa
26.06%
In this thesis, I investigate the behavior of rational individuals making decisions involving externalities and explain why seemingly irrational behavior can be the result of the decisions of rational individuals. In particular, I consider two kinds of externalities: an information externality and an action externality. In Chapter two, I characterize the equilibria of a dynamic game with an information externality and an action externality where players with private information make decisions in a sequential but exogenous order. I investigate the effects of different job evaluation criteria on the players' behavior in a two-stage model. I find that if the evaluation is based on a relative measure instead of an absolute measure, herding may occur much earlier, resulting in less efficient information aggregation and heavier loss in social welfare. In Chapter three, I characterize the asymmetric pure strategy equilibria of a dynamic game with a pure information externality where players choose whether to invest as well as when to invest. I find that any asymmetric pure strategy equilibrium is more efficient than the symmetric mixed strategy equilibrium which is the focus of the existing literature. I also find that when players become very patient...

## Essais sur la gestion des ressources forestières

Tatoutchoup, Francis Didier
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
Relevância na Pesquisa
26.1%
Cette thèse est composée de trois essais en économie forestière. Les deux premiers s'intéressent à la fixation de la redevance optimale à laquelle fait face le propriétaire d'une ressource forestière dans un contexte d'information asymétrique. Le troisième analyse l'impact à long terme du recyclage sur la surface de terre affectée à la forêt. La gestion des ressources forestières implique souvent la délégation des droits de coupe par le propriétaire forestier à une entreprise exploitante. Cette délégation prend la forme d'un contrat de concession par lequel le propriétaire forestier octroie les droits d'exploitation aux compagnies forestières, en contrepartie d'une redevance (transfert monétaire). L'octroie des droits d'exploitation s'effectue généralement sous plusieurs modes, dont les plus répandus sont les appels d'offres publics et les contrats de gré à gré, où le propriétaire forestier et la firme exploitante spécifient entre autres la redevance dans les clauses d'exploitation de la forêt. Pour déterminer le mécanisme optimal (choix de la firme, âge de coupe et redevance), le propriétaire forestier a idéalement besoin de connaître les coûts de coupe et de reboisement. Or en réalité...

## Informação assimétrica no mercado de seguros de saúde em Portugal

Bago d'Uva, Teresa Maria Marreiros
Fonte: Instituto Superior de Economia e Gestão Publicador: Instituto Superior de Economia e Gestão
Relevância na Pesquisa
26.07%

## Secure Degrees of Freedom of MIMO X-Channels with Output Feedback and Delayed CSIT

Zaidi, Abdellatif; Awan, Zohaib Hassan; Shamai, Shlomo; Vandendorpe, Luc
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.08%
We investigate the problem of secure transmission over a two-user multi-input multi-output (MIMO) X-channel in which channel state information is provided with one-unit delay to both transmitters (CSIT), and each receiver feeds back its channel output to a different transmitter. We refer to this model as MIMO X-channel with asymmetric output feedback and delayed CSIT. The transmitters are equipped with M-antennas each, and the receivers are equipped with N-antennas each. For this model, accounting for both messages at each receiver, we characterize the optimal sum secure degrees of freedom (SDoF) region. We show that, in presence of asymmetric output feedback and delayed CSIT, the sum SDoF region of the MIMO X-channel is same as the SDoF region of a two-user MIMO BC with 2M-antennas at the transmitter, N-antennas at each receiver and delayed CSIT. This result shows that, upon availability of asymmetric output feedback and delayed CSIT, there is no performance loss in terms of sum SDoF due to the distributed nature of the transmitters. Next, we show that this result also holds if only output feedback is conveyed to the transmitters, but in a symmetric manner, i.e., each receiver feeds back its output to both transmitters and no CSIT. We also study the case in which only asymmetric output feedback is provided to the transmitters...

## Experimental Realization of $1 \to 2$ Asymmetric Phase-Covariant Quantum Cloning

Chen, Hongwei; Zhou, Xianyi; Suter, Dieter; Du, Jiangfeng
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26%
While exact cloning of an unknown quantum state is prohibited by the linearity of quantum mechanics, approximate cloning is possible and has been used, e.g., to derive limits on the security of quantum communication protocols. In the case of asymmetric cloning, the information from the input state is distributed asymmetrically between the different output states. Here, we consider asymmetric phase-covariant cloning, where the goal is to optimally transfer the phase information from a single input qubit to different output qubits. We construct an optimal quantum cloning machine for two qubits that does not require ancilla qubits and implement it on an NMR quantum information processor.; Comment: 6 pages, 5 figures

## Simulation of continuous variable quantum games without entanglement

Li, Shang-Bin
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.03%
A simulation scheme of quantum version of Cournot's Duopoly is proposed, in which there is a new Nash equilibrium that may be also Pareto optimal without any entanglement involved. The unique property of this simulation scheme is decoherence-free against the symmetric photon loss. Furthermore, we analyze the effects of the asymmetric information on this simulation scheme and investigate the case of asymmetric game caused by asymmetric photon loss. A second-order phase transition-like behavior of the average profits of the firm 1 and firm 2 in Nash equilibrium can be observed with the change of the degree of asymmetry of the information or the degree of "virtual cooperation". It is also found that asymmetric photon loss in this simulation scheme plays a similar role with the asymmetric entangled states in the quantum game. PACS numbers: 02.50.Le, 03.67.-a; Comment: 7 pages, 4 figures, RevTex, some contents have been revised

## Directional genetic differentiation and asymmetric migration

Sundqvist, Lisa; Zackrisson, Martin; Kleinhans, David
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.05%
In the field of population genetics measures of genetic differentiation are widely used to gather information on the structure and gene flow between populations. These measures are based on a number of simplifying assumptions, for instance equal population size and symmetric migration. However, asymmetric migration frequently occurs in nature and information about directional gene flow would here be of great interest. Nevertheless current measures of genetic differentiation cannot be used in such systems without violating their assumptions. To get information on asymmetric migration patterns from genetic data rather complex models using maximum likelihood or Bayesian approaches generally need to be applied. We here introduce a new approach that intends to fill the gap between the complex approaches and the symmetric measures of genetic differentiation. Our approach makes it possible to calculate a directional component of genetic differentiation at low computational effort using any of the classical measures of genetic differentiation. The directional measures of genetic differentiation can further be used to calculate asymmetric migration. Using a simulated dataset with known migration, directional differentiation and migration are estimated to show that our method captures relevant properties of migration patterns even at low migration frequencies and with few marker loci.; Comment: 14 pages...

## Nonbinary Quantum Cyclic and Subsystem Codes Over Asymmetrically-decohered Quantum Channels

Aly, Salah A.; Ashikhmin, Alexei
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.03%
Quantum computers theoretically are able to solve certain problems more quickly than any deterministic or probabilistic computers. A quantum computer exploits the rules of quantum mechanics to speed up computations. However, one has to mitigate the resulting noise and decoherence effects to avoid computational errors in order to successfully build quantum computers. In this paper, we construct asymmetric quantum codes to protect quantum information over asymmetric quantum channels, $\Pr Z \geq \Pr X$. Two generic methods are presented to derive asymmetric quantum cyclic codes using the generator polynomials and defining sets of classical cyclic codes. Consequently, the methods allow us to construct several families of quantum BCH, RS, and RM codes over asymmetric quantum channels. Finally, the methods are used to construct families of asymmetric subsystem codes.

## Cognitive Wyner Networks with Clustered Decoding

Lapidoth, Amos; Levy, Nathan; Shamai, Shlomo; Wigger, Michele
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
26.06%
We study an interference network where equally-numbered transmitters and receivers lie on two parallel lines, each transmitter opposite its intended receiver. We consider two short-range interference models: the "asymmetric network," where the signal sent by each transmitter is interfered only by the signal sent by its left neighbor (if present), and a "symmetric network," where it is interfered by both its left and its right neighbors. Each transmitter is cognizant of its own message, the messages of the $t_\ell$ transmitters to its left, and the messages of the $t_r$ transmitters to its right. Each receiver decodes its message based on the signals received at its own antenna, at the $r_\ell$ receive antennas to its left, and the $r_r$ receive antennas to its right. For such networks we provide upper and lower bounds on the multiplexing gain, i.e., on the high-SNR asymptotic logarithmic growth of the sum-rate capacity. In some cases our bounds meet, e.g., for the asymmetric network. Our results exhibit an equivalence between the transmitter side-information parameters $t_\ell, t_r$ and the receiver side-information parameters $r_\ell, r_r$ in the sense that increasing/decreasing $t_\ell$ or $t_r$ by a positive integer $\delta$ has the same effect on the multiplexing gain as increasing/decreasing $r_\ell$ or $r_r$ by $\delta$. Moreover---even in asymmetric networks---there is an equivalence between the left side-information parameters \$t_\ell...

## REVISIÓN DE LA LITERATURA SOBRE EL PRESUPUESTO EN CINCO PERIÓDICOS INTERNACIONALES DESDE EL AÑO 2000 HASTA EL 2009; LITERATURE REVIEW ON BUDGET IN FIVE YEARS IN INTERNATIONAL JOURNALS FROM 2000 TO 2009; REVISÃO DA LITERATURA SOBRE ORÇAMENTO EM CINCO PERIÓDICOS INTERNACIONAIS NOS ANOS DE 2000 ATÉ 2009

Gomes, Giancarlo; Lavarda, Carlos Eduardo Facin; Torrens, Edson Wilson
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf