869 resultados para Time-varying bond risk premia
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PURPOSE: Infection is the leading complication of long-term central venous catheters, and its incidence may vary according to catheter type. The objective of this study was to compare the frequency and probability of infection between two types of long-term intravenous devices. METHODS: Retrospective study in 96 onco-hematology patients with partially implanted catheters (n = 55) or completely implanted ones (n = 42). Demographic data and catheter care were similar in both groups. Infection incidence and infection-free survival were used for the comparison of the two devices. RESULTS: In a median follow-up time of 210 days, the catheter-related infection incidence was 0.2102/100 catheter-days for the partially implanted devices and 0.0045/100 catheter-days for the completely implanted devices; the infection incidence rate was 46.7 (CI 95% = 6.2 to 348.8). The 1-year first infection-free survival ratio was 45% versus 97%, and the 1-year removal due to infection-free survival ratio was 42% versus 97% for partially and totally implanted catheters, respectively (P <.001 for both comparisons). CONCLUSION: In the present study, the infection risk was lower in completely implanted devices than in partially implanted ones.
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The present Work Project (WP) is the result of Sonae’s concern with fraud risk, seeking to implement a method that formally describes and evaluates it in its various forms. In a context of limited human, capital, time and tools’ resources, the Internal Audit (IA) department of the company developed a framework to raise the awareness of top management and identify which processes of its value chain present a higher level of exposure to fraud, with the purpose of redirecting attention to those and prioritizing the creation of new mechanisms to monitor its KPIs’ dynamics.
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This paper analyses the Portuguese stock market since it reopened in 1977, with a special focus on the evolution of the statistic and stochastic characteristics of the market return throughout this 36 year period. The market return for the period of time between 1977 and 2012 (September 28th) is estimated and then compared with the return that would have been achieved with Government bonds and treasury bills, which allows us to confirm that the hierarchy of return / risk across the different financial instruments is verified. The market risk premium for this 36 year period is also estimated and a comparison with other markets is performed, suggesting that the Portuguese market’s risk has not been compensated by an adequate return. The study also examines the evolution of the Portuguese market’s volatility in the 1977-2012 period and compares it with other markets, showing the existence of extremely high peaks during the first 11 years, but indicating a downwards trend throughout the whole period under analysis. Finally, the correlation between market returns for Portugal and for other countries and the degree of integration are estimated and their evolution throughout time is assessed, leading to the conclusion that the performance of the Portuguese stock market has become increasingly correlated with major European markets – correlation with some markets close to 0.70 from 2000 onwards-, but that country-specific risk factors are still relevant.
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Externally bonded strengthening of masonry structures using Fiber Reinforced Polymers (FRPs) has been accepted as a promising technique. Although the effectiveness of FRPs in improving the performance of masonry components has been extensively investigated, their long-term performance and durability remain poorly addressed. This paper, tackling one of the aspects related to durability of these systems, presents an experimental investigation on the effect of long-term (one year) water immersion on the performance of GFRP-strengthened bricks. The tests include materials' mechanical tests, as well as pull-off and single-lap shear bond tests, to investigate the changes in material properties and bond behavior with immersion time, respectively. The effect of mechanical surface treatment on the durability of the strengthened system as well as the reversibility of the degradation upon partial drying are also investigated. The experimental results are presented and critically discussed.
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The use of Near Surface Mounted (NSM) Fiber Reinforced Polymers (FRPs) for strengthening masonry structures can be a suitable substitute for Externally Bonded Reinforcement (EBR) technique. NSM technique has many advantages such as larger bonded area, better anchorage capacity, higher resistance, higher percentage exploitation of the FRP and reduced installation time. However, information regarding the effectiveness of this strengthening technique for masonry structures is scarce and characterization of the critical mechanisms such as bond behavior is necessary. This paper presents experimental investigation of the bond performance in NSM-strengthened brick specimens. CFRP laminates are used for NSM strengthening of masonry bricks with different bonded lengths. The bond between FRP and masonry substrate is investigated by performing conventional pull-out tests and the experimental results are presented and discussed.
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Security risk management is by definition, a subjective and complex exercise and it takes time to perform properly. Human resources are fundamental assets for any organization, and as any other asset, they have inherent vulnerabilities that need to be handled, i.e. managed and assessed. However, the nature that characterize the human behavior and the organizational environment where they develop their work turn these task extremely difficult, hard to accomplish and prone to errors. Assuming security as a cost, organizations are usually focused on the efficiency of the security mechanisms implemented that enable them to protect against external attacks, disregarding the insider risks, which are much more difficult to assess. All these demands an interdisciplinary approach in order to combine technical solutions with psychology approaches in order to understand the organizational staff and detect any changes in their behaviors and characteristics. This paper intends to discuss some methodological challenges to evaluate the insider threats and its impacts, and integrate them in a security risk framework, that was defined according to the security standard ISO/IEC_JTC1, to support the security risk management process.
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Although most of the accidents occurred in Olive Oil Mill (OOM) resulted from “basic” risks, there is a need to apply adequate tools to support risk decisions that can meet the specificities of this sector. This study aims to analyse the views of Occupational, Safety & Health (OSH) practitioners about the risk assessment process in OOM, identifying the key difficulties inherent to the risk assessment process in these sector, as well as identifying some improvements to the current practice. This analysis was based on a questionnaire that was developed and applied to 13 OSH practitioners working at OOM. The results showed that the time available to perform the risk assessment is the more frequent limitation. They believe that the methodologies available are not an important limitation to this process. However, a specific risk assessment methodology, that includes acceptance criteria adjusted to the OOM reality, using risk metrics supported on the frequency of accidents and workdays lost, were indicated as being also an important contributions improve the process. A semi-quantitative approach, complemented with the use of the sector accident statistics, can be a good solution for this sector. However, further strategies should also be adopted, mainly those that can lead to an easy application of the risk assessment process.
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Buruli Ulcer (BU) is a neglected infectious disease caused by Mycobacterium ulcerans that is responsible for severe necrotizing cutaneous lesions that may be associated with bone involvement. Clinical presentations of BU lesions are classically classified as papules, nodules, plaques and edematous infiltration, ulcer or osteomyelitis. Within these different clinical forms, lesions can be further classified as severe forms based on focality (multiple lesions), lesions' size (>15 cm diameter) or WHO Category (WHO Category 3 lesions). There are studies reporting an association between delay in seeking medical care and the development of ulcerative forms of BU or osteomyelitis, but the effect of time-delay on the emergence of lesions classified as severe has not been addressed. To address both issues, and in a cohort of laboratory-confirmed BU cases, 476 patients from a medical center in Allada, Benin, were studied. In this laboratory-confirmed cohort, we validated previous observations, demonstrating that time-delay is statistically related to the clinical form of BU. Indeed, for non-ulcerated forms (nodule, edema, and plaque) the median time-delay was 32.5 days (IQR 30.0-67.5), while for ulcerated forms it was 60 days (IQR 20.0-120.0) (p = 0.009), and for bone lesions, 365 days (IQR 228.0-548.0). On the other hand, we show here that time-delay is not associated with the more severe phenotypes of BU, such as multi-focal lesions (median 90 days; IQR 56-217.5; p = 0.09), larger lesions (diameter >15 cm) (median 60 days; IQR 30-120; p = 0.92) or category 3 WHO classification (median 60 days; IQR 30-150; p = 0.20), when compared with unifocal (median 60 days; IQR 30-90), small lesions (diameter =15 cm) (median 60 days; IQR 30-90), or WHO category 1+2 lesions (median 60 days; IQR 30-90), respectively. Our results demonstrate that after an initial period of progression towards ulceration or bone involvement, BU lesions become stable regarding size and focal/multi-focal progression. Therefore, in future studies on BU epidemiology, severe clinical forms should be systematically considered as distinct phenotypes of the same disease and thus subjected to specific risk factor investigation.
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Compelling biological and epidemiological evidences point to a key role of genetic variants of the TERT and TERC genes in cancer development. We analyzed the genetic variability of these two gene regions using samples of 2,267 multiple myeloma (MM) cases and 2,796 healthy controls. We found that a TERT variant, rs2242652, is associated with reduced MM susceptibility (OR?=?0.81; 95% CI: 0.72-0.92; p?=?0.001). In addition we measured the leukocyte telomere length (LTL) in a subgroup of 140 cases who were chemotherapy-free at the time of blood donation and 468 controls, and found that MM patients had longer telomeres compared to controls (OR?=?1.19; 95% CI: 0.63-2.24; ptrend ?=?0.01 comparing the quartile with the longest LTL versus the shortest LTL). Our data suggest the hypothesis of decreased disease risk by genetic variants that reduce the efficiency of the telomerase complex. This reduced efficiency leads to shorter telomere ends, which in turn may also be a marker of decreased MM risk.
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OBJECTIVE: To determine the risk factors for mortality related to myocardial revascularization when performed in association with coronary endarterectomy. METHODS: We assessed retrospectively 353 patients who underwent 373 coronary endarterectomies between January '89 and November '98, representing 3.73% of the myocardial revascularizations in this period of time. The arteries involved were as follows: right coronary artery in 218 patients (58.45%); left anterior descending in 102 patients (27.35%); circumflex artery in 39 patients (10.46%); and diagonal artery in 14 patients (3.74%). We used 320 (85.79%) venous grafts and 53 (14.21%) arterial grafts. RESULTS: In-hospital mortality among our patients was 9.3% as compared with 5.7% in patients with myocardial revascularizations without endarterectomy (p=0.003). Cause of death was related to acute myocardial infarction in 18 (54.55%) patients. The most significant risk factors for mortality identified were as follows: diabetes mellitus (p=0.001; odds ratio =7.168), left main disease (<0.001; 9.283), female sex (0.01; 3.111), acute myocardial infarction (0.02; 3.546), ejection fraction <35% (<0.001; 5.89), and previous myocardial revascularization (<0.001; 4.295). CONCLUSION: Coronary endarterectomy is related to higher mortality, and the risk factors involved are important elements of a poor outcome.
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OBJECTIVE - To analyze the trends in risk of death due to cardiovascular diseases in the northern, northeastern, southern, southeastern, and central western Brazilian geographic regions from 1979 to 1996. METHODS - Data on mortality due to cardiovascular, cardiac ischemic, and cerebrovascular diseases in 5 Brazilian geographic regions were obtained from the Ministry of Health. Population estimates for the time period from 1978 to 1996 in the 5 Brazilian geographic regions were calculated by interpolation with the Lagrange method, based on the census data from 1970, 1980, 1991, and the population count of 1996, for each age bracket and sex. Trends were analyzed with the multiple linear regression model. RESULTS - Cardiovascular diseases showed a declining trend in the southern, southeastern, and northern Brazilian geographic regions in all age brackets and for both sexes. In the northeastern and central western regions, an increasing trend in the risk of death due to cardiovascular diseases occurred, except for the age bracket from 30 to 39 years, which showed a slight reduction. This resulted from the trends of cardiac ischemic and cerebrovascular diseases. The analysis of the trend in the northeastern and northern regions was impaired by the great proportion of poorly defined causes of death. CONCLUSION - The risk of death due to cardiovascular, cerebrovascular, and cardiac ischemic diseases decreased in the southern and southeastern regions, which are the most developed regions in the country, and increased in the least developed regions, mainly in the central western region.
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OBJECTIVE: To identify risk factors for acute myocardial infarction during the postoperative period after myocardial revascularization. METHODS: This was a case-control study paired for sex, age, number, type of graft used, coronary endarterectomy, type of myocardial protection, and use of extracorporeal circulation. We assessed 178 patients (89 patients in each group) undergoing myocardial revascularization, and the following variables were considered: dyslipidemia, systemic hypertension, smoking, diabetes mellitus, previous myocardial revascularization surgery, previous coronary angioplasty, and acute myocardial infarction. RESULTS: Baseline clinical characteristics did not differ in the groups, except for previous myocardial revascularization surgery, prevalent in the case group (34 patients vs. 12 patients; p = 0.0002). This was the only independent predictor of risk for acute myocardial infarction in the postoperative period, based on a multivariate logistic regression analysis (p=0.0001). Mortality and the time of hospital stay of the case group were significantly higher (19.1% vs. 1.1%; p<0.001 and 15.7 days vs. 10.6 days; p<0.05 respectively) than those of the control. CONCLUSION: Only previous myocardial revascularization was an independent predictor of acute myocardial infarction in the postoperative period, based on multivariate logistic regression analysis.
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Background:Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Knowledge about cardiovascular risk factors (CVRFs) in young adults and their modification over time are measures that change the risks and prevent CVDs.Objectives:To determine the presence of CVRFs and their changes in different health care professionals over a period of 20 years.Methods:All students of medicine, nursing, nutrition, odontology, and pharmacy departments of Federal University of Goiás who agreed to participate in this study were evaluated when they started their degree courses and 20 years afterward. Questionnaires on CVRFs [systemic arterial hypertension (SAH), diabetes mellitus, dyslipidemia, and family history of early CVD, smoking, alcohol consumption, and sedentarism] were administered. Cholesterol levels, blood sugar levels, blood pressure, weight, height, and body mass index were determined. The Kolmogorov-Smirnov test was used to evaluate distribution, the chi-square test was used to compare different courses and sexes, and the McNemar test was used for comparing CVRFs. The significance level was set at a p value of < 0.05.Results:The first stage of the study included 281 individuals (91% of all the students), of which 62.9% were women; the mean age was 19.7 years. In the second stage, 215 subjects were reassessed (76% of the initial sample), of which 59.07% were women; the mean age was 39.8 years. The sample mostly consisted of medical students (with a predominance of men), followed by nursing, nutrition, and pharmacy students, with a predominance of women (p < 0.05). Excessive weight gain, SAH, and dyslipidemia were observed among physicians and dentists (p < 0.05). Excessive weight gain and SAH and a reduction in sedentarism (p < 0.05) were observed among pharmacists. Among nurses there was an increase in excessive weight and alcohol consumption (p < 0.05). Finally, nutritionists showed an increase in dyslipidemia (p < 0.05).Conclusion:In general, there was an unfavorable progression of CVRFs in the population under study, despite it having adequate specialized knowledge about these risk factors.
When is the Best Time for the Second Antiplatelet Agent in Non-St Elevation Acute Coronary Syndrome?
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Abstract Dual antiplatelet therapy is a well-established treatment in patients with non-ST elevation acute coronary syndrome (NSTE-ACS), with class I of recommendation (level of evidence A) in current national and international guidelines. Nonetheless, these guidelines are not precise or consensual regarding the best time to start the second antiplatelet agent. The evidences are conflicting, and after more than a decade using clopidogrel in this scenario, benefits from the routine pretreatment, i.e. without knowing the coronary anatomy, with dual antiplatelet therapy remain uncertain. The recommendation for the upfront treatment with clopidogrel in NSTE-ACS is based on the reduction of non-fatal events in studies that used the conservative strategy with eventual invasive stratification, after many days of the acute event. This approach is different from the current management of these patients, considering the established benefits from the early invasive strategy, especially in moderate to high-risk patients. The only randomized study to date that specifically tested the pretreatment in NSTE-ACS in the context of early invasive strategy, used prasugrel, and it did not show any benefit in reducing ischemic events with pretreatment. On the contrary, its administration increased the risk of bleeding events. This study has brought the pretreatment again into discussion, and led to changes in recent guidelines of the American and European cardiology societies. In this paper, the authors review the main evidence of the pretreatment with dual antiplatelet therapy in NSTE-ACS.
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Abstract Background: Heart disease in pregnancy is the leading cause of non- obstetric maternal death. Few Brazilian studies have assessed the impact of heart disease during pregnancy. Objective: To determine the risk factors associated with cardiovascular and neonatal complications. Methods: We evaluated 132 pregnant women with heart disease at a High-Risk Pregnancy outpatient clinic, from January 2005 to July 2010. Variables that could influence the maternal-fetal outcome were selected: age, parity, smoking, etiology and severity of the disease, previous cardiac complications, cyanosis, New York Heart Association (NYHA) functional class > II, left ventricular dysfunction/obstruction, arrhythmia, drug treatment change, time of prenatal care beginning and number of prenatal visits. The maternal-fetal risk index, Cardiac Disease in Pregnancy (CARPREG), was retrospectively calculated at the beginning of prenatal care, and patients were stratified in its three risk categories. Results: Rheumatic heart disease was the most prevalent (62.12%). The most frequent complications were heart failure (11.36%) and arrhythmias (6.82%). Factors associated with cardiovascular complications on multivariate analysis were: drug treatment change (p = 0.009), previous cardiac complications (p = 0.013) and NYHA class III on the first prenatal visit (p = 0.041). The cardiovascular complication rates were 15.22% in CARPREG 0, 16.42% in CARPREG 1, and 42.11% in CARPREG > 1, differing from those estimated by the original index: 5%, 27% and 75%, respectively. This sample had 26.36% of prematurity. Conclusion: The cardiovascular complication risk factors in this population were drug treatment change, previous cardiac complications and NYHA class III at the beginning of prenatal care. The CARPREG index used in this sample composed mainly of patients with rheumatic heart disease overestimated the number of events in pregnant women classified as CARPREG 1 and > 1, and underestimated it in low-risk patients (CARPREG 0).