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The kallikrein-kinin system (KKS) has been previously linked to glucose homeostasis. In isolated muscle or fat cells, acute bradykinin (BK) stimulation was shown to improve insulin action and increase glucose uptake by promoting glucose... more
The kallikrein-kinin system (KKS) has been previously linked to glucose homeostasis. In isolated muscle or fat cells, acute bradykinin (BK) stimulation was shown to improve insulin action and increase glucose uptake by promoting glucose transporter 4 translocation to plasma membrane. However, the role for BK in the pathophysiology of obesity and type 2 diabetes remains largely unknown. To address this, we generated genetically obese mice (ob/ob) lacking the BK B2 receptor (obB2KO). Despite similar body weight or fat accumulation, obB2KO mice showed increased fasting glycemia (162.3 ± 28.2 mg/dl vs 85.3 ± 13.3 mg/dl), hyperinsulinemia (7.71 ± 1.75 ng/ml vs 4.09 ± 0.51 ng/ml) and impaired glucose tolerance when compared with ob/ob control mice (obWT), indicating insulin resistance and impaired glucose homeostasis. This was corroborated by increased glucose production in response to a pyruvate challenge. Increased gluconeogenesis was accompanied by increased hepatic mRNA expression of ...
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In this article, the innovative twostage procedure of Simar and Wilson (2007) is used to estimate the efficiency determinants of Portuguese hotel groups from 1998 to 2005. In the first stage, the hotels’ technical efficiency is estimated... more
In this article, the innovative twostage procedure of Simar and Wilson (2007) is used to estimate the efficiency determinants of Portuguese hotel groups from 1998 to 2005. In the first stage, the hotels’ technical efficiency is estimated with Data Envelopment Analysis (DEA), in order to establish which hotels have the most efficient performance. These could serve as peers to help
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Page 1. Bootstrapped Technical Efficiency of African Seaports Carlos Pestana Barros, Albert Assaf, and Ade Ibiwoye Abstract This paper analyzes the efficiency of a representative sample of African seaports using a bootstrapped DEA Data... more
Page 1. Bootstrapped Technical Efficiency of African Seaports Carlos Pestana Barros, Albert Assaf, and Ade Ibiwoye Abstract This paper analyzes the efficiency of a representative sample of African seaports using a bootstrapped DEA Data Envelopment Analysis approach. ...
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In this paper, we assess and compare the performance of French tourism destinations, using the Data Envelopment Analysis (DEA) two-stage procedure, where in the first stage the efficiency score are calculated, and then followed in the... more
In this paper, we assess and compare the performance of French tourism destinations, using the Data Envelopment Analysis (DEA) two-stage procedure, where in the first stage the efficiency score are calculated, and then followed in the second stage by a bootstrapped truncated regression model. In the context of France such analysis takes an additional importance, especially as the country is
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We compared the prognostic value of liver biopsy (LB) and FIB-4 index in patients with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection. We studied patients from the Grupo de Estudio del SIDA 3603 study cohort, in... more
We compared the prognostic value of liver biopsy (LB) and FIB-4 index in patients with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection. We studied patients from the Grupo de Estudio del SIDA 3603 study cohort, in whom fibrosis was evaluated at baseline using both LB (Metavir score) and FIB-4 index. We assessed overall death (OD) and liver-related events (LREs), defined as decompensation or hepatocellular carcinoma, whichever occurred first. We used receiver operating characteristic (ROC) curves to determine the ability of LB and FIB-4 to predict outcomes. We also assessed the association between advanced fibrosis-LB (F3 or greater) or FIB-4 (≥3.25)-and outcomes using multivariate Cox regression analysis. The study sample comprised 903 patients (328 with sustained virologic response [SVR]). Baseline fibrosis by LB was as follows: F0, n = 71; F1, n = 242; F2, n = 236; F3, n = 236; F4, n = 118. Fibrosis by FIB-4 was as follows: ≤1, n = 148; >1 to <3.25, ...
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This paper compares the efficiency of cooperatives and private enterprises in the Portuguese wine industry, employing data envelopment analysis (DEA). The use of DEA for the analysis of comparative efficiency within a sector is a key tool... more
This paper compares the efficiency of cooperatives and private enterprises in the Portuguese wine industry, employing data envelopment analysis (DEA). The use of DEA for the analysis of comparative efficiency within a sector is a key tool in evaluating organizational competitiveness. Competitiveness should be based on benchmarking the different types of organizations that comprise the viniculture sector. We conclude that Portuguese wine cooperatives, on average, are more efficient than their private counterparts. Economic implications arising from the study are discussed.
This article introduces the Data Envelopment Analysis (DEA) bootstrap procedure to analyze the technical efficiency of Brazilian first league football clubs. For comparison purpose the study also estimates the efficiency scores with the... more
This article introduces the Data Envelopment Analysis (DEA) bootstrap procedure to analyze the technical efficiency of Brazilian first league football clubs. For comparison purpose the study also estimates the efficiency scores with the traditional DEA model. From the results, it is clear that there is a significant difference between the efficiency scores derived from the traditional DEA and the bootstrap
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... sample of Portuguese travel agencies. They adopted which permits an observed DMU to reach the pro-a model that generates efficiency scores econome-duction frontier. ... In more economic terms, this function makes it but with a linear... more
... sample of Portuguese travel agencies. They adopted which permits an observed DMU to reach the pro-a model that generates efficiency scores econome-duction frontier. ... In more economic terms, this function makes it but with a linear homogeneity cost function and a ...
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This paper analyses the cost efficiency of Angola-Luanda hotels using a Bayesian stochastic frontier model. The results confirm that Luanda hotels have increased their cost efficiency over the period of study to reach an overall average... more
This paper analyses the cost efficiency of Angola-Luanda hotels using a Bayesian stochastic frontier model. The results confirm that Luanda hotels have increased their cost efficiency over the period of study to reach an overall average of 67.11%. Results from the returns to scale also indicate that further improvements in efficiency are possible if Luanda hotels would increase the size
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This article employs a mixed logit bounded random parameter model to analyze the returning preferences of tourists visiting the city of Lisbon, Portugal. The results show that accommodation characteristics and destination attributes... more
This article employs a mixed logit bounded random parameter model to analyze the returning preferences of tourists visiting the city of Lisbon, Portugal. The results show that accommodation characteristics and destination attributes (accommodation range, events, food quality, expected weather beach, overall quality, reputation, and safety) have a positive and significant impact on the probability of returning to the city. The model comparison shows that the mixed logit bounded random parameter outperforms the traditional mixed logit model and leads to more accurate conclusions.
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The effects of vertical banded gastroplasty/Roux-en-Y gastric bypass (Capella) on the esophageal mucosa of patients with histological esophagitis are poorly understood. To evaluate long-term effects, we investigated the persistence,... more
The effects of vertical banded gastroplasty/Roux-en-Y gastric bypass (Capella) on the esophageal mucosa of patients with histological esophagitis are poorly understood. To evaluate long-term effects, we investigated the persistence, aggravation or disappearance of histological esophagitis in patients with morbid obesity and reflux esophagitis (diagnosed by endoscopic biopsy) after Roux-en-Y gastric bypass. Twenty-one patients with morbid obesity and esophagitis (histological diagnosis) were submitted to gastric bypass (Fobi-Capella technique) and underwent upper endoscopy and esophageal biopsy during the late postoperative period. The mean age of the patients was 42.57 +/- 7.49 years (30 to 56). Nineteen (90.48%) patients were women, and two (9.52%) were men. Before surgery, the patients presented a mean weight of 124.26 +/- 19.09 kg and a mean body mass index (BMI) of 48.46 +/- 6.37 kg/m(2). Thirteen (61.90%) patients had endoscopic esophagitis before surgery. The mean weight and BMI were 81.65 +/- 13.16 kg and 31.91 +/- 4.99 kg/m(2), respectively, during the late postoperative period (29.80 +/- 8.91 months). The mean percentage of excess weight loss was 68.7 +/- 14.6%. Among the 21 patients with a preoperative histological diagnosis of reflux esophagitis, five (23.18%) had the same diagnosis after surgery, and four (19.04%) continued to present findings of endoscopic esophagitis. Vertical banded gastroplasty/Roux-en-Y gastric bypass (Capella technique) is effective in the treatment of reflux esophagitis. No association was observed between the percentage of excess weight loss and improvement of esophagitis.
Research Interests: Treatment Outcome, Prospective studies, Humans, Weight Loss, Female, and 17 moreMale, Follow-up studies, Body Mass Index, Risk factors, Obesity Surgery, Clinical Sciences, Middle Aged, Body mass index (BMI), Adult, Public health systems and services research, Morbid Obesity, Risk Factors, Gastric Bypass, Long Term Effect, Prospective Study, Postoperative Period, and Surgical Treatment
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This paper analyzes technical efficiency in Angolan banks from 2005 to 2010 with an innovative Data Envelopment Analysis (DEA) model, the B-Convexity model. The intermediate approach is adopted and the results reveal that efficiency... more
This paper analyzes technical efficiency in Angolan banks from 2005 to 2010 with an innovative Data Envelopment Analysis (DEA) model, the B-Convexity model. The intermediate approach is adopted and the results reveal that efficiency varies among the banks analyzed. Policy implications are derived.
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MEL is a key source for peer-reviewed research and policy perspectives of direct relevance to economists, researchers, academics and those in professional practice with an interest in maritime economics, maritime policy, transport... more
MEL is a key source for peer-reviewed research and policy perspectives of direct relevance to economists, researchers, academics and those in professional practice with an interest in maritime economics, maritime policy, transport economics and applied economics.
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Research Interests: Microbiology, Medical Microbiology, Hepatitis C, Lipids, Antiretroviral Therapy, and 16 moreHumans, Female, Male, Hypercholesterolemia, Risk factors, Antimicrobial chemotherapy, Triglycerides, Aged, Middle Aged, Adult, Highly Active Antiretroviral Therapy, Risk Factors, High Density Concrete, Low Risk, Total Cholesterol, and Hypertriglyceridemia
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... The analysis of travel agencies' efficiency is somehow restricted to two papers (Bell and Morey, 1995; Anderson et al., 1999b ... and that public ownership seems to be a sig-nificant disadvantage on grounds of efficiency (Barros,... more
... The analysis of travel agencies' efficiency is somehow restricted to two papers (Bell and Morey, 1995; Anderson et al., 1999b ... and that public ownership seems to be a sig-nificant disadvantage on grounds of efficiency (Barros, 2004 ... Stochastic Cobb–Douglas cost frontier model ...
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Abstract This paper analyzes sports managers' earnings and blends traditional aspects of man-agement derived from human capital theory with new aspects derived from social capital theory. It captures the integrative and relational... more
Abstract This paper analyzes sports managers' earnings and blends traditional aspects of man-agement derived from human capital theory with new aspects derived from social capital theory. It captures the integrative and relational aspects of sports management. In 2000, ...
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Abstract: The enhanced role of occupational and personal pension plans in providing retirement income raises issues concerning efficiency and performance. 1 This paper evaluates the performance of Portuguese pension fund management... more
Abstract: The enhanced role of occupational and personal pension plans in providing retirement income raises issues concerning efficiency and performance. 1 This paper evaluates the performance of Portuguese pension fund management companies from ...
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... The former is captured by entering the relevant variable into the model, while the latter is captured by entering random parameters into the model. ... Fig. 1. Wind farms and capacity (Mw). Source: Portuguese Minister of Economy. View... more
... The former is captured by entering the relevant variable into the model, while the latter is captured by entering random parameters into the model. ... Fig. 1. Wind farms and capacity (Mw). Source: Portuguese Minister of Economy. View Within Article. ...
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This paper analyses the technical efficiency in the hydroelectric generating plants of a main Portuguese electricity enterprise EDP (Electricity of Portugal) between 1994 and 2004, investigating the role played by increase in competition... more
This paper analyses the technical efficiency in the hydroelectric generating plants of a main Portuguese electricity enterprise EDP (Electricity of Portugal) between 1994 and 2004, investigating the role played by increase in competition and regulation. A random cost frontier method is adopted. A translog frontier model is used and the maximum likelihood estimation technique is employed to estimate the empirical
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This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company... more
This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927-2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non-stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long-run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation.