Accounting and Economic Rates of Return: a Dynamic Econometric Investigation

Many studies have questioned empirical utilization of accounting data as internal rates of return would be more consistent with the relevant economic concept. The paper investigates the dynamic relationships between different measures of accounting rates of return (ARRs) and different approximations for the internal rates of returns (IRRs). In contrast with the prevailing case-study investigations, one considers a panel for quoted Brazilian firms in the manufacturing industry along the 1988-3/2003-2 period. Granger causality tests are considered and even though the results are not completely clear cut, some discernible uni-directional patterns emerge. In particular, there seems to be informational content between economic and accounting rates of return, between ROA (Net Profits/Total Assets) and PM (Gross Profits/ Operational Income), and internal rates of return. This seems to indicate that there is some validity in using accounting rates of return in certain economic studies.

Tacit Collusion under Imperfect Monitoring in the Canadian Manufacturing Industry: An Empirical Study

The paper undertakes a cross-sectoral analysis of a salient empirical implication of the model of tacit collusion advanced by Abreu et al (1986). Specifically, the prevalence of a first order Markovian process for alternating between price wars and collusive periods is assessed by means of non-parametric tests. The analysis focuses on 30 different industries in Canada. The evidence provides weak support for optimal collusion in one industry, which is consistent with the idea that such collusive arrangements are unusual.tacit collusion, game theory, Canada, price war

Measuring Market Conduct in the Brazilian Cement Industry: a Dynamic Econometric Investigation

Indirect assessments of market conduct have become widespread in the New Empirical Industrial Organization-NEIO literature. Recently, Steen and Salvanes (1999) provided a flexible dynamic econometric formulation of the approach advanced by Bresnahan (1982) and Lau (1982). The present paper considers a similar approach as applied to regional cement markets in Brazil under more favorable data availability and it also attempts to address part of the critiques that usually emerge with respect to the NEIO literature. In particular, issues pertaining to structural stability and yet the control for the number of competing firms are addressed. The evidence clearly indicates non-negligible and distinct market power in the different regions and yet distinct conduct patterns in the short and long-run.

Cavitation effects on the pressure distribution of a squeeze film damper bearing

High speed motion pictures have revealed several operating regimes in a squeeze film damper. Pressure measurements corresponding to these distinct regimes were made to examine their effect on the performance of such dampers. Visual observation also revealed the means by which the pressure in the feed groove showed higher amplitudes than the theory predicts. Comparison between vapor and gaseous cavitation are made based on their characteristic pressure wave, and the effect this has on the total force and its phase

Tacit collusion under imperfect monitoring in the Canadian manufacturing industry: An empirical study

The paper undertakes a cross-sectoral analysis of a salient empirical implication of the model of tacit collusion advanced by Abreu et al (1986). Specifically, the prevalence of a first order Markovian process for alternating between price wars and collusive periods is assessed by means of non-parametric tests. The analysis focuses on 30 different industries in Canada. The evidence provides weak support for optimal collusion in one industry, which is consistent with the idea that such collusive arrangements are unusual

Lionel Robbins: a methodological reappraisal

Lionel Robbins contributions are often discussed in terms of two main aspects. First, the delineation of the scope of economics in terms of decision making conditional on scarcity. Second, a more methodological concern with respect to scientific neutrality and the possibility of meaningful separation between positive and normative statements in economics. The related demarcation issue is subject to intense debate and Robbins is often associated with a strong neutrality view [see e.g. Davis (2005), Mongin (2006)]. This paper attempts to situate Robbins aprioristic point of view in terms of posterior methodological developments. In particular, the methodology of scientific research programmes (MSRP) advanced by Lakatos (1968, 1970) has been subject to adaptations in the context of economics by Latsis (1976) in an attempt to accommodate different degrees of apriorism, falsificationism and conventionalism as scientific criteria in economics. The historical path towards Robbins's (1932, 1935) essay appears to be well documented [see e.g. Howson (2004)]. The paper aims at clarifying the role of Robbins's essay in shaping the dominant research programme in Economics, and contends that the author's definition of economics is central to the main elements of the hard core of contemporary research programmes in line with the neoclassical research programme

How I Manage Transplant Ineligible Patients with Myelodysplastic Neoplasms

Myelodysplastic neoplasms, formerly known as myelodysplastic syndromes (MDS), represent a group of clonal disorders characterized by a high degree of clinical and molecular heterogeneity, and an invariable tendency to progress to acute myeloid leukemia. MDS typically present in the elderly with cytopenias of different degrees and bone marrow dysplasia, the hallmarks of the disease. Allogeneic hematopoietic stem cell transplant is the sole curative approach to date. Nonetheless, given the disease's demographics, only a minority of patients can benefit from this procedure. Currently used prognostic schemes such as the Revised International Prognostic Scoring System (R-IPSS), and most recently the molecular IPSS (IPSS-M), guide clinical management by dividing MDS into two big categories: lower- and higher-risk cases, based on a cut-off score of 3.5. The main clinical problem of the lower-risk group is represented by the management of cytopenias, whereas the prevention of secondary leukemia progression is the goal for the latter. Herein, we discuss the non-transplant treatment of MDS, focusing on current practice and available therapeutic options, while also presenting new investigational agents potentially entering the MDS therapeutic arsenal in the near future

Dynamic Entry and Exit Linkages in the Brazilian Manufacturing Industry: An Econometric Investigation

The paper investigates dynamic linkages between entry and exit rates in Brazilian manufacturing in the context of 231 (4-digits) industries during the 1996-2005 period. The empirical analysis focuses on the estimation of a dynamic panel data for entry and exit rates and controls for the business cycle. The empirical evidence is consistent with a multiplier effect where synergetic factors prevail either by entry inducing entry or by exit inducing exit. Evidence partially supports a competition effect that could be related to a selection process favouring efficiency, as exit induces entry. The business cycle control variable appears to play no role. The results are similar, though not identical to previous evidence for developed countries

Purification and characterization of phosphofructokinase from rhodotorula glutinis

Phosphofructokinase has been identified and purified from extracts of Rhodotorula glutinius. Kinetic studies of the enzyme indicated high cooperativity with respect to fructose 6-phosphate. The kinetics for ATP shows no cooperativity as indicated by the hyperbolic behavior of the enzyme. The enzyme is inhibited by ADP. Citrate and phosphate have no effect on the enzyme activity. The role of ATB, fructose 6-phosphate, and ADP is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24371/1/0000640.pd

The Role of Protein Tyrosine Phosphatase (PTP)-1B in Cardiovascular Disease and Its Interplay with Insulin Resistance.

Endothelial dysfunction is a key feature of cardiovascular disorders associated with obesity and diabetes. Several studies identified protein tyrosine phosphatase (PTP)-1B, a member of the PTP superfamily, as a major negative regulator for insulin receptor signaling and a novel molecular player in endothelial dysfunction and cardiovascular disease. Unlike other anti-diabetic approaches, genetic deletion or pharmacological inhibition of PTP1B was found to improve glucose homeostasis and insulin signaling without causing lipid buildup in the liver, which represents an advantage over existing therapies. Furthermore, PTP1B was reported to contribute to cardiovascular disturbances, at various molecular levels, which places this enzyme as a unique single therapeutic target for both diabetes and cardiovascular disorders. Synthesizing selective small molecule inhibitors for PTP1B is faced with multiple challenges linked to its similarity of sequence with other PTPs; however, overcoming these challenges would pave the way for novel approaches to treat diabetes and its concurrent cardiovascular complications. In this review article, we summarized the major roles of PTP1B in cardiovascular disease with special emphasis on endothelial dysfunction and its interplay with insulin resistance. Furthermore, we discussed some of the major challenges hindering the synthesis of selective inhibitors for PTP1B