85 research outputs found
A transitional analysis of the welfare cost of inflation
This paper applies new computational methods for studying nonstationary dynamics to reevaluate the welfare cost of inflation. A dynamic stochastic general equilibrium model with heterogeneous agents is studied. Incomplete markets induce agents to hold a fiat currency as insurance against idiosyncratic income fluctuations. Rather than comparing steady state equilibria, I measure the welfare cost of inflation by explicitly modeling the transitional dynamics that arise following a change in monetary policy. Transitional dynamics are shown to increase the welfare cost of inflation substantially. Also, contrary to conventional wisdom, transitional dynamic effects are shown to increase the benefits of reducing the inflation rate.Econometric models ; Inflation (Finance) ; Monetary policy ; Money ; Welfare
A transitional analysis of the welfare cost of inflation
This paper applies new computational methods for studying nonstationary dynamics to reevaluate the welfare cost of inflation. A dynamic stochastic general equilibrium model with heterogeneous agents is studied. Incomplete markets induce agents to hold a fiat currency as insurance against idiosyncratic income fluctuations. Rather than comparing steady state equilibria, I measure the welfare cost of inflation by explicitly modeling the transitional dynamics that arise following a change in monetary policy. Transitional dynamics are shown to increase the welfare cost of inflation substantially. Also, contrary to conventional wisdom, transitional dynamic effects are shown to increase the benefits of reducing the inflation rate
Ernst Freund as Precursor of the Rational Study of Corporate Law
Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe
Interaction between COMT rs5993883 and second generation antipsychotics is linked to decreases in verbal cognition and cognitive control in bipolar disorder
Abstract
Background
Second generation antipsychotics (SGAs) are increasingly utilized in Bipolar Disorder (BD) but are potentially associated with cognitive side effects. Also linked to cognitive deficits associated with SGA-treatment are catechol-O-methyltransferase (COMT) gene variants. In this study, we examine the relationship between cognition in SGA use and COMT rs5993883 in cohort sample of subjects with BD.
Methods
Interactions between SGA-treatment and COMT rs5993883 genotype on cognition was tested using a battery of neuropsychological tests performed in cross-sectional study of 246 bipolar subjects.
Results
The mean age of our sample was 40.15 years and was comprised of 70 % female subjects. Significant demographic differences included gender, hospitalizations, benzodiazepine/antidepressant use and BD-type diagnosis. Linear regressions showed that the COMT rs5993883 GG genotype predicted lower verbal learning (p = 0.0006) and memory (p = 0.0026) scores, and lower scores on a cognitive control task (p = 0.004) in SGA-treated subjects. Interestingly, COMT GT- or TT-variants showed no intergroup cognitive differences. Further analysis revealed an interaction between SGA-COMT GG-genotype for verbal learning (p = 0.028), verbal memory (p = 0.026) and cognitive control (p = 0.0005).
Conclusions
This investigation contributes to previous work demonstrating links between cognition, SGA-treatment and COMT rs5993883 in BD subjects. Our analysis shows significant associations between cognitive domains such as verbal-cognition and cognitive control in SGA-treated subjects carrying the COMT rs5993883 GG-genotype. Prospective studies are needed to evaluate the clinical significance of these findings.http://deepblue.lib.umich.edu/bitstream/2027.42/134550/1/40359_2016_Article_118.pd
Cognitive impairment in patients with a schizoaffective disorder: a comparison with bipolar patients in euthymia
OBJECTIVES: Several studies have shown persistent neurocognitive impairment in patients with a bipolar affective disorder (BD) even in euthymia as well as in patients with a schizoaffective disorder (SAD). The aim of our study was to compare the neuropsychological performance between these two groups. Confounding variables were controlled to enhance our understanding of cognitive dysfunction in both BD and SAD. METHODS: Several domains of neurocognitive function, executive function, memory, attention, concentration and perceptuomotor function were examined in 28 euthymic SAD patients and 32 BD patients by using a neuropsychological test battery. The Hamilton Depression Rating Scale (HAMD), Montgomery-Asberg Depression Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) were used to evaluate the patients' clinical status. Data analysis was performed by using a multivariate analysis of covariance (ANCOVA/MANCOVA). RESULTS: Euthymic SAD patients showed greater cognitive impairment than euthymic BD patients in the tested domains including declarative memory and attention. Putative significant group differences concerning cognitive flexibility vanished when controlled for demographic and clinical variables. Age and medication were robust predictors to cognitive performance of both SAD and BD patients. CONCLUSIONS: Our results point out the worse cognitive outcome of SAD compared to BD patients in remission. Remarkably, the variance is higher for some of the test results between the groups than within each group, this being discussed in light of the contradictive concept of SAD
Space Science Opportunities Augmented by Exploration Telepresence
Since the end of the Apollo missions to the lunar surface in December 1972, humanity has exclusively conducted scientific studies on distant planetary surfaces using teleprogrammed robots. Operations and science return for all of these missions are constrained by two issues related to the great distances between terrestrial scientists and their exploration targets: high communication latencies and limited data bandwidth.
Despite the proven successes of in-situ science being conducted using teleprogrammed robotic assets such as Spirit, Opportunity, and Curiosity rovers on the surface of Mars, future planetary field research may substantially overcome latency and bandwidth constraints by employing a variety of alternative strategies that could involve: 1) placing scientists/astronauts directly on planetary surfaces, as was done in the Apollo era; 2) developing fully autonomous robotic systems capable of conducting in-situ field science research; or 3) teleoperation of robotic assets by humans sufficiently proximal to the exploration targets to drastically reduce latencies and significantly increase bandwidth, thereby achieving effective human telepresence.
This third strategy has been the focus of experts in telerobotics, telepresence, planetary science, and human spaceflight during two workshops held from October 3–7, 2016, and July 7–13, 2017, at the Keck Institute for Space Studies (KISS). Based on findings from these workshops, this document describes the conceptual and practical foundations of low-latency telepresence (LLT), opportunities for using derivative approaches for scientific exploration of planetary surfaces, and circumstances under which employing telepresence would be especially productive for planetary science. An important finding of these workshops is the conclusion that there has been limited study of the advantages of planetary science via LLT. A major recommendation from these workshops is that space agencies such as NASA should substantially increase science return with greater investments in this promising strategy for human conduct at distant exploration sites
Space Science Opportunities Augmented by Exploration Telepresence
Since the end of the Apollo missions to the lunar surface in December 1972, humanity has exclusively conducted scientific studies on distant planetary surfaces using teleprogrammed robots. Operations and science return for all of these missions are constrained by two issues related to the great distances between terrestrial scientists and their exploration targets: high communication latencies and limited data bandwidth.
Despite the proven successes of in-situ science being conducted using teleprogrammed robotic assets such as Spirit, Opportunity, and Curiosity rovers on the surface of Mars, future planetary field research may substantially overcome latency and bandwidth constraints by employing a variety of alternative strategies that could involve: 1) placing scientists/astronauts directly on planetary surfaces, as was done in the Apollo era; 2) developing fully autonomous robotic systems capable of conducting in-situ field science research; or 3) teleoperation of robotic assets by humans sufficiently proximal to the exploration targets to drastically reduce latencies and significantly increase bandwidth, thereby achieving effective human telepresence.
This third strategy has been the focus of experts in telerobotics, telepresence, planetary science, and human spaceflight during two workshops held from October 3–7, 2016, and July 7–13, 2017, at the Keck Institute for Space Studies (KISS). Based on findings from these workshops, this document describes the conceptual and practical foundations of low-latency telepresence (LLT), opportunities for using derivative approaches for scientific exploration of planetary surfaces, and circumstances under which employing telepresence would be especially productive for planetary science. An important finding of these workshops is the conclusion that there has been limited study of the advantages of planetary science via LLT. A major recommendation from these workshops is that space agencies such as NASA should substantially increase science return with greater investments in this promising strategy for human conduct at distant exploration sites
Aqueous hydroxylation mediated synthesis of crystalline calcium uranate particles
Metal uranates(VI) are solubility limiting U(VI) phases under high pH conditions and may act as suitable long-term wasteforms. The precipitation and thermal phase development mechanisms of calcium uranate particles formed via aqueous hydroxylation reactions are studied in order to address the lack of aqueous synthesis methods currently available. Hydrous Ca-deficient uranate particles formed from aqueous solutions saturated in U(VI) oligomers were found to thermally decompose via several weight-loss steps between 100 and 800 °C. Crystalline calcium uranate (Ca2U3O11) is initially formed at 700 °C via dehydration and dehydroxylation-olation reactions under redox-neutral conditions. This initial phase decomposes to biphasic CaUO4-UO2 particles at 800 °C via a reductive pathway
Towards a self-deploying and gliding robot
Strategies for hybrid locomotion such as jumping and gliding are used in nature by many different animals for traveling over rough terrain. This combination of locomotion modes also allows small robots to overcome relatively large obstacles at a minimal energetic cost compared to wheeled or flying robots. In this chapter we describe the development of a novel palm sized robot of 10\,g that is able to autonomously deploy itself from ground or walls, open its wings, recover in midair and subsequently perform goal- directed gliding. In particular, we focus on the subsystems that will in the future be integrated such as a 1.5\,g microglider that can perform phototaxis; a 4.5\,g, bat-inspired, wing folding mechanism that can unfold in only 50\,ms; and a locust-inspired, 7\,g robot that can jump more than 27 times its own height. We also review the relevance of jumping and gliding for living and robotic systems and we highlight future directions for the realization of a fully integrated robot
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