201 research outputs found
Cytosolic redox components regulate protein homeostasis via additional localisation in the mitochondrial intermembrane space
Oxidative protein folding is confined to the bacterial periplasm, endoplasmic reticulum and the mitochondrial intermembrane space. Maintaining a redox balance requires the presence of reductive pathways. The major thiol-reducing pathways engage the thioredoxin and the glutaredoxin systems which are involved in removal of oxidants, protein proofreading and folding. Alterations in redox balance likely affect the flux of these redox pathways and are related to ageing and diseases such as neurodegenerative disorders and cancer. Here, we first review the well-studied oxidative and reductive processes in the bacterial periplasm and the endoplasmic reticulum, and then discuss the less understood process in the mitochondrial intermembrane space, highlighting its importance for the proper function of the cell
Does Independence Matter? Case Studies from Colombia
This study consists of two parts: I. ) Does Independence Matter? The Case of the Colombian Central Bank, andII. ) Does Independence Improve Performance? The Colombian Superintendency of Banks. Why has Colombia been a case of low output variability and moderate-to-high inflation? This paper argues that regardless of the institutional arrangement, monetary authorities have stabilized the business cycle, and inflation control has not been the only objective of monetary policy. The government-controlled Junta Monetaria (1963-1991) often ignored the advice of the Asesores, an anti-inflation group of technocrats who had no voting powers. Since 1991 the independent and powerful members of Junta Directiva have been engaged in inflation targeting but continue to place weight on output and employment stabilization in their objective function. Institutional reform has implied a slow reduction in inflation. For a faster decline, the current system requires either greater accountability (for not meeting the inflation targets) or less weight on output stabilization.
Determinants of Labor Demand in Colombia: 1976-1996
Colombia's unemployment rate rose to 20% during the late 1990s from less than 8% in 1994. This paper argues that this has been the result of high non-wage labor costs embodied in the legislation. The estimated own-wage labor demand elasticity is around 0.5, which implies that a reduction in those costs, while politically costly, can have a significant payoff in terms of equity and efficiency. We also find that adjustment costs of changing employment as well as wage elasticities were not affected by changes in the regulations regarding severance payments and dismissal costs. In this sense, structural reforms did have an impact on labor demand through its effect on relative prices alone. Finally, we conclude that the wage elasticity of labor demand increases (in absolute terms) during contractions. Hence, the increase in prices and the beginning of a recession had a significant effect on employment.
Oil, Coffee and the Dynamic Commons Problems in Colombia
The dynamic commons problem arises when different groups in society engage in intense redistributive activity as a result of an export boom. This paper analyzes the role that institutions play in ameliorating that problem in the case of coffee and oil in Colombia. The paper presents a model that rationalizes the existence of a federation of coffee producers that effectively reduces inefficient redistribution to other sectors of society. According to the empirical evidence we find that domestic coffee prices have been unaffected by political factors, so that in practice appropriation of coffee rents does not depend on electoral and partisan cycles. The case of oil is substantially different. Here, rents are claimed by a large number of divided agents. According to the model, one feasible solution to the dynamic commons problem when the fiscal structure is not unitary is to impose a set of rules that restrict appropriations by different groups during windfalls. The major cost of this solution, embodied in the Oil Stabilization Fund, is the total loss of flexibility.
Iron–sulfur clusters: from metals through mitochondria biogenesis to disease
Iron–sulfur clusters are ubiquitous inorganic co-factors that contribute to a wide range of cell pathways including the maintenance of DNA integrity, regulation of gene expression and protein translation, energy production, and antiviral response. Specifically, the iron–sulfur cluster biogenesis pathways include several proteins dedicated to the maturation of apoproteins in different cell compartments. Given the complexity of the biogenesis process itself, the iron–sulfur research area constitutes a very challenging and interesting field with still many unaddressed questions. Mutations or malfunctions affecting the iron–sulfur biogenesis machinery have been linked with an increasing amount of disorders such as Friedreich’s ataxia and various cardiomyopathies. This review aims to recap the recent discoveries both in the yeast and human iron–sulfur cluster arena, covering recent discoveries from chemistry to disease
Political Institutions and Policy Outcomes in Colombia: The Effects of the 1991 Constitution
The 1991 Colombian Constitution strengthened the checks and balances of the political system by enhancing the role of Congress and the Constitutional Court, while somewhat limiting the powers of the President (who nonetheless remains extremely powerful even by Latin American standards). As a consequence of the larger number of relevant players, and the removal of barriers that restricted political participation, the political system has gained in terms of representation. However, political transaction costs have increased, making cooperation harder to achieve. We show that this has been typically the case in fiscal policy, where the use of rigid rules, the constitutionalization of some policies, and a reduction in legislative success rates-due to the presence of a more divided and fragmented Congress-have limited the adaptability and flexibility of policies. In contrast, in other areas of policy that were formally delegated to the technocracy, such as monetary policy and regulation of public utilities, policies have been more adaptable to economic shocks, delivering better outcomes.
An investigation on thermal performance characteristics of hollow-core vacuum insulated panels
As concerns over climate change stimulate legislation for performance improvement
in the building industry, in an effort to mitigate embodied and operational
carbon footprint, high performance insulating solutions are gaining attention and
invite further research in this area. Hollow-core VIPs are an alternative vacuum insulating
technology that can provide thin insulating cladding solutions while avoiding
some vulnerabilities of high performance insulating materials such as fumed silica
VIPs.This thesis aims to develop and evaluate the performance of a conceptual prototype
of hollow-core VIPs. Initial simulations of a simplied model were used to
evaluate desirable values for main parameters such as emissivity and panel thickness.
Desirable panel thickness lies between 20 and 50mm to eliminate convection at a
pressure of 0.01 Pa and emissivity lower than 0.1 is necessary to stifle radiation.
A more detailed model representing a node within a full size VIP was developed
and tested in a vacuum chamber and compared to transient simulations to study
its thermal performance. Nodes with three structural array congurations were
manufactured from stainless steel, PTFE and epoxy resin to analyse performance
in different panel thicknesses (25 and 50mm) and with different internal surface
emissivity
English Language Learning through Physical and Social Environment Interaction at Adolfo Kolping School
A través de una serie de clases piloto, este proyecto de investigación tuvo como objetivo introducir la enseñanza didáctica del idioma inglés en estudiantes de primaria a través del compromiso con el entorno físico y social proporcionado por la escuela. Tuvo como fin examinar hábitos, actitudes, experiencias y eventos, el enfoque de investigación se construyó mediante la aplicación de encuestas, cuestionarios, conocimientos y observaciones del proceso de enseñanza. Se recopiló alguna información. Se desarrollaron clases piloto con 22 alumnos de quinto grado de la Escuela Técnica Adolfo Kolping, con el objetivo de poner en práctica métodos de enseñanza que desarrollarán determinadas habilidades en los alumnos y promoverán la interacción con el entorno escolar a través de la experimentación con el mundo real, en el que para la realización del estudio se han utilizado todo tipo de elementos de la escuela.Through a series of pilot classes, this research project aimed to introduce didactic teaching of the English language in elementary school students through engagement with the physical and social environment provided by the school. In order to examine habits, attitudes, experiences and events, the research approach was built through the application of surveys, questionnaires, knowledge and observations of the teaching process. Some information was collected. Pilot classes were developed with 22 students from the fifth grade of Adolfo Kolping Technical School, with the aim of putting into practice teaching methods that will develop certain skills in students and promote interaction with the school environment through experimentation with the real world, in which all kinds of elements of the school have been used to carry out the study
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