125 research outputs found

    Comportamento Individual: alternativas ao homem econômico

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    Quais são os pressupostos comportamentais da moderna teoria econômica? O objetivo do artigo é tragar a evolução e analisar o conceito de 'homem econômico' utilizado na teoria econômica, assim como apresentar as principais alternativas teóricas para a explicação do comportamento individual: 'homem ético', 'homem contratual' e 'homem sub-racional'. What are the behavioural foundations of modem economic theory? This paper is an attempt to trace out and analyse the evolution of the 'economic man' construct in modem economics, and to review the main alternative explanatory hypotheses that have been framed to account for the behaviour of the individual economic agent: 'ethical man'; 'contractual man' and sub-rational man'

    Resenha Bibliográfica

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    GALBRAITH, John K. O Pensamento Econômico em Perspectiva: Uma HistóriaCrítica. Tradução de Carlos A. Malferrari. Sao Paulo, Editora Pioneira/EDUSP, 1989,189 p

    Energia e a economia brasileira

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    Um levantamento, ainda que sumário, dos temas que têm sido objeto de estudo sistemático por parte de economistas e cientistas sociais nos últimos anos, seguramente apontaria a questão energética como a que maior espaço vem conquistando no universo das preocupações norteadoras do pensamento econômico e social contemporâneo

    Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton–proton collisions at the LHC

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    This paper presents the method and performance of primary vertex reconstruction in proton–proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of √s=8 TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about 30μm is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than 20μm and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing

    Soluble Alpha Klotho in Acromegaly: comparison with traditional markers of disease activity

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    Abstract Context: Soluble alpha klotho (sαKL) has been linked to growth hormone (GH) action, but systematic evaluation and comparisons with traditional biomarkers in acromegaly are lacking.Objective: To evaluate the potential of sαKL to aid classification of disease activity. Methods: This retrospective study at 2 academic centers included acromegaly patients before surgery (A, n = 29); after surgery (controlled, discordant, or uncontrolled) without most discordant patients. A cutoff of 1548 pg/mL for sαKL discriminated controlled (B1, C1) and uncontrolled (B3, C3) patients with 97.8% (88.4%-99.9%) sensitivity and 100% (77.1%-100%) specificity. sαKL was below the cutoff in 84% of the discordant subjects. In the remaining 16%, elevated sαKL and IGF-I persisted, despite normal random GH. Sex, age, body mass index, and markers of bone and calcium metabolism did not significantly affect sαKL concentrations. Conclusion: Our data support sαKL as a biomarker to assess disease activity in acromegaly. sαKL exhibits close association with GH secretory status, large dynamic range, and robustness toward biological confounders. Its measurement could be helpful particularly when GH and IGF-I provide discrepant information (B1, B2, B3, n = 28, 11, 8); or with somatostatin analogue treatment (C1, C2, C3, n = 17, 11, 5); nonfunctioning pituitary adenomas (n = 20); and healthy controls (n = 31). sαKL was measured by immunoassay and compared with traditional biomarkers (random and nadir GH, insulin-like growth factor I [IGF-I], IGF binding protein 3). Associations with disease activity were assessed.Results: sαKL was correlated to traditional biomarkers, particularly IGF-I (rs =0.80, P <0.0001). High concentrations before treatment (A, median, interquartile range: 4.04 × upper limit of normal [2.26-8.08]) dropped to normal after treatment in controlled and in most discordant patients. A cutoff of 1548 pg/mL for sαKL discriminated controlled (B1, C1) and uncontrolled (B3, C3) patients with 97.8% (88.4%-99.9%) sensitivity and 100% (77.1%-100%) specificity. sαKL was below the cutoff in 84% of the discordant subjects. In the remaining 16%, elevated sαKL and IGF-I persisted, despite normal random GH. Sex, age, body mass index, and markers of bone and calcium metabolism did not significantly affect sαKL concentrations.Conclusion: Our data support sαKL as a biomarker to assess disease activity in acromegaly. sαKL exhibits close association with GH secretory status, large dynamic range, and robustness toward biological confounders. Its measurement could be helpful particularly when GH and IGF-I provide discrepant information

    Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial

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    Aims The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM). Methods and results ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction). Conclusion This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without D

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Evaluation of the effects of sodium–glucose co‐transporter 2 inhibition with empagliflozin on morbidity and mortality in patients with chronic heart failure and a preserved ejection fraction: rationale for and design of the EMPEROR‐Preserved Trial

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    Background: The principal biological processes that characterize heart failure with a preserved ejection fraction (HFpEF) are systemic inflammation, epicardial adipose tissue accumulation, coronary microcirculatory rarefaction, myocardial fibrosis and vascular stiffness; the resulting impairment of left ventricular and aortic distensibility (especially when accompanied by impaired glomerular function and sodium retention) causes increases in cardiac filling pressures and exertional dyspnoea despite the relative preservation of left ventricular ejection fraction. Independently of their actions on blood glucose, sodium–glucose co‐transporter 2 (SGLT2) inhibitors exert a broad range of biological effects (including actions to inhibit cardiac inflammation and fibrosis, antagonize sodium retention and improve glomerular function) that can ameliorate the pathophysiological derangements in HFpEF. Such SGLT2 inhibitors exert favourable effects in experimental models of HFpEF and have been found in large‐scale trials to reduce the risk for serious heart failure events in patients with type 2 diabetes, many of whom were retrospectively identified as having HFpEF. Study design: The EMPEROR‐Preserved Trial is enrolling ≈5750 patients with HFpEF (ejection fraction &gt;40%), with and without type 2 diabetes, who are randomized to receive placebo or empagliflozin 10 mg/day, which is added to all appropriate treatments for HFpEF and co‐morbidities. Study aims: The primary endpoint is the time‐to‐first‐event analysis of the combined risk for cardiovascular death or hospitalization for heart failure. The trial will also evaluate the effects of empagliflozin on renal function, cardiovascular death, all‐cause mortality and recurrent hospitalization events, and will assess a wide range of biomarkers that reflect important pathophysiological mechanisms that may drive the evolution of HFpEF. The EMPEROR‐Preserved Trial is well positioned to determine if empagliflozin can have a meaningful impact on the course of HFpEF, a disorder for which there are currently few therapeutic options

    Evaluation of the effect of sodium–glucose co‐transporter 2 inhibition with empagliflozin on morbidity and mortality of patients with chronic heart failure and a reduced ejection fraction: rationale for and design of the EMPEROR‐Reduced trial

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    Drugs that inhibit the sodium–glucose co‐transporter 2 (SGLT2) have been shown to reduce the risk of hospitalizations for heart failure in patients with type 2 diabetes. In populations that largely did not have heart failure at the time of enrolment, empagliflozin, canagliflozin and dapagliflozin decreased the risk of serious new‐onset heart failure events by ≈30%. In addition, in the EMPA‐REG OUTCOME trial, empagliflozin reduced the risk of both pump failure and sudden deaths, the two most common modes of death among patients with heart failure. In none of the three trials could the benefits of SGLT2 inhibitors on heart failure be explained by the actions of these drugs as diuretics or anti‐hyperglycaemic agents. These observations raise the possibility that SGLT2 inhibitors could reduce morbidity and mortality in patients with established heart failure, including those without diabetes. The EMPEROR‐Reduced trial is enrolling ≈3600 patients with heart failure and a reduced left ventricular ejection fraction (≤ 40%), half of whom are expected not to have diabetes. Patients are being randomized to placebo or empagliflozin 10 mg daily, which is added to all appropriate treatment with inhibitors of the renin–angiotensin system and neprilysin, beta‐blockers and mineralocorticoid receptor antagonists. The primary endpoint is the time‐to‐first event analysis of the combined risk of cardiovascular death and hospitalization for heart failure, but the trial will also evaluate the effects of empagliflozin on renal function, cardiovascular death, all‐cause mortality, and recurrent hospitalization events. By adjusting eligibility based on natriuretic peptide levels to the baseline ejection fraction, the trial will preferentially enrol high‐risk patients. A large proportion of the participants is expected to have an ejection fraction &lt; 30%, and the estimated annual event rate is expected to be at least 15%. The EMPEROR‐Reduced trial is well‐positioned to determine if the addition of empagliflozin can add meaningfully to current approaches that have established benefits in the treatment of chronic heart failure with left ventricular systolic dysfunction

    Baseline characteristics of patients with heart failure with preserved ejection fraction in the EMPEROR-Preserved trial.

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    AIMS: EMPEROR-Preserved is an ongoing trial evaluating the effect of empagliflozin in patients with heart failure with preserved ejection fraction (HFpEF). This report describes the baseline characteristics of the EMPEROR-Preserved cohort and compares them with patients enrolled in prior HFpEF trials. METHODS AND RESULTS: EMPEROR-Preserved is a phase III randomized, international, double-blind, parallel-group, placebo-controlled trial in which 5988 symptomatic HFpEF patients [left ventricular ejection fraction (LVEF) >40%] with and without type 2 diabetes mellitus (T2DM) have been enrolled. Patients were required to have elevated N-terminal pro B-type natriuretic peptide (NT-proBNP) concentrations (i.e. >300?pg/mL in patients without and >900?pg/mL in patients with atrial fibrillation) along with evidence of structural changes in the heart or documented history of heart failure hospitalization. Among patients enrolled from various regions (45% Europe, 11% Asia, 25% Latin America, 12% North America), the mean age was 72?±?9?years, 45% were women. Almost all patients had New York Heart Association class II or III symptoms (99.6%), and 23% had prior heart failure hospitalization within 12?months. Thirty-three percent of the patients had baseline LVEF of 41-50%. The mean LVEF (54?±?9%) was slightly lower while the median NT-proBNP [974 (499-1731) pg/mL] was higher compared with previous HFpEF trials. Presence of comorbidities such as diabetes (49%) and chronic kidney disease (50%) were common. The majority of the patients were on angiotensin-converting enzyme inhibitors/angiotensin receptor blockers/angiotensin receptor-neprilysin inhibitors (80%) and beta-blockers (86%), and 37% of patients were on mineralocorticoid receptor antagonists. CONCLUSION: When compared with prior trials in HFpEF, the EMPEROR-Preserved cohort has a somewhat higher burden of comorbidities, lower LVEF, higher median NT-proBNP and greater use of mineralocorticoid receptor antagonists at baseline. Results of the EMPEROR-Preserved trial will be available in 2021
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