578 research outputs found
Corporate Social Responsibility and Corporate Financial Performance: Evidence from Korea
This paper studies the empirical relation between corporate social responsibility (CSR) and corporate financial performance in Korea using a sample of 1122 firm-years during 2002-2008. We measure corporate social responsibility by both an equal-weighted CSR index and a stakeholder-weighted CSR index suggested by Akpinar et al. (2008). Corporate financial performance is measured by ROE, ROA and Tobin’s Q. We find a positive and significant relation between corporate financial performance and the stakeholder-weighted CSR index, but not the equal-weighted CSR index. This finding is robust to alternative model specifications and several additional tests, providing evidence in support of instrumental stakeholder theory.corporate social responsibility; corporate financial performance; KEJI index; instrumental stakeholder theory
The uncalibrated pulse contour cardiac output during off-pump coronary bypass surgery: performance in patients with a low cardiac output status and a reduced left ventricular function
BACKGROUND: We compared the continuous cardiac index measured by the FloTrac/Vigileo™ system (FCI) to that measured by a pulmonary artery catheter (CCI) with emphasis on the accuracy of the FCI in patients with a decreased left ventricular ejection fraction (LVEF) and a low cardiac output status during off-pump coronary bypass surgery (OPCAB). We also assessed the influence of several factors affecting the pulse contour, such as the mean arterial pressure (MAP), the systemic vascular resistance index (SVRI) and the use of norepinephrine.
METHODS: Fifty patients who were undergoing OPCAB (30 patients with a LVEF ≥ 40%, 20 patients with a LVEF < 40%) were enrolled. The FCI and CCI were measured and we performed a Bland-Altman analysis. Subgroup analyses were done according to the LVEF (< 40%), the CCI (≤ 2.4 L/min/m), the MAP (60-80 mmHg), the SVRI (1,600-2,600 dyne/s/cm(5)/m(2)) and the use of norepinephrine.
RESULTS: The FCI was reliable at all the time points of measurement with an overall bias and limit of agreement of -0.07 and 0.67 L/min/m(2), respectively, resulting in a percentage error of 26.9%. The percentage errors in the patients with a decreased LVEF and in a low cardiac output status were 28.2% and 22.3%, respectively. However, the percentage error in the 91 data pairs outside the normal range of the SVRI was 40.2%.
CONCLUSIONS: The cardiac output measured by the FloTrac/Vigileo™ system was reliable even in patients with a decreased LVEF and in a low cardiac output status during OPCAB. Acceptable agreement was also noted during the period of heart displacement and grafting of the obtuse marginalis branch.ope
Interrupted aortic arch diagnosed with loss of femoral pulse in a patient undergoing patent ductus arteriosus ligation -A case report-
A 12-year-old boy with ventricular septal defect and patent ductus arteriosus was presented to the operating room. Upon clamping the patent ductus arteriosus, the femoral arterial pressure curve was lost; however, it returned upon unclamping. Upon further dissection, an interrupted aortic arch was found between the left subclavian artery and patent ductus arteriosus. The surgery was discontinued for further evaluation
Effect of preoperative statin therapy on myocardial protection and morbidity endpoints following off-pump coronary bypass surgery in patients with elevated C-reactive protein level
BACKGROUND: The aim of this study was to investigate the effects of preoperative statin therapy on myocardial protection and morbidity endpoints following off-pump coronary bypass graft surgery (OPCAB) in patients with elevated serum high-sensitivity C-reactive protein (hs-CRP) levels.
METHODS: Of the 492 patients who underwent multivessel OPCAB from March 2007 to February 2009, the records of 144 patients whose baseline hs-CRP level > 2 mg/L were reviewed. According to the history of preoperative statin therapy for at least one week, patients were classified as either statin group or control group (72 subjects each). Preoperative and operative characteristics and postoperative data including troponin (Tn)-T level and major morbidity endpoints were obtained and compared. Major morbidity endpoints were defined as permanent stroke, renal dysfunction, hemostatic re-exploration, deep sternal wound infection, and the number of patients requiring prolonged ventilation.
RESULTS: Preoperative and operative characteristics were similar between the two groups. There were no significant differences in the incidence of morbidity endpoints between the two groups, except for the number of patients requiring dialysis, which was significantly lower in the statin group (8 vs. 1, P = 0.033). Tn-T level at 24 h after surgery was also significantly lower in the statin group.
CONCLUSIONS: In this study, we observed beneficial effects of preoperative statin therapy for at least one week in terms of less myocardial enzyme release and fewer patients requiring dialysis following OPCAB in patients whose preoperative hs-CRP was elevatedope
Earnings management surrounding CEO turnover: evidence from Korea
This article examines the empirical relation between CEO turnover and earnings management in Korea using a sample of 317 CEO turnovers and 634 non-turnover control firms during the period of 2001-2008. We classify CEO turnovers into four types depending on whether the departure of outgoing CEO is peaceful or forced and the incoming CEO is promoted from within or recruited from outside the firm. We measure earnings management by both discretionary accruals and real activities management. We also control for the potential endogeneity of CEO turnover using Heckman’s two-stage approach. After controlling for corporate financial performance and governance structure, we find upward earnings management by the departing CEO only when the departure is forced and the new CEO is an insider. In this case, the new CEO also engages in downward earnings management using both discretionary accruals and real activities management. We also find some evidence that the new CEO recruited from outside the firm manages discretionary accruals upward following the peaceful departure of predecessor. In all other types of CEO turnover, we do not find evidence of significant earnings management by either CEO
Earnings management surrounding CEO turnover: evidence from Korea
This article examines the empirical relation between CEO turnover and earnings management in Korea using a sample of 317 CEO turnovers and 634 non-turnover control firms during the period of 2001-2008. We classify CEO turnovers into four types depending on whether the departure of outgoing CEO is peaceful or forced and the incoming CEO is promoted from within or recruited from outside the firm. We measure earnings management by both discretionary accruals and real activities management. We also control for the potential endogeneity of CEO turnover using Heckman’s two-stage approach. After controlling for corporate financial performance and governance structure, we find upward earnings management by the departing CEO only when the departure is forced and the new CEO is an insider. In this case, the new CEO also engages in downward earnings management using both discretionary accruals and real activities management. We also find some evidence that the new CEO recruited from outside the firm manages discretionary accruals upward following the peaceful departure of predecessor. In all other types of CEO turnover, we do not find evidence of significant earnings management by either CEO
Boosting Learning for LDPC Codes to Improve the Error-Floor Performance
Low-density parity-check (LDPC) codes have been successfully commercialized
in communication systems due to their strong error correction capabilities and
simple decoding process. However, the error-floor phenomenon of LDPC codes, in
which the error rate stops decreasing rapidly at a certain level, presents
challenges for achieving extremely low error rates and deploying LDPC codes in
scenarios demanding ultra-high reliability. In this work, we propose training
methods for neural min-sum (NMS) decoders to eliminate the error-floor effect.
First, by leveraging the boosting learning technique of ensemble networks, we
divide the decoding network into two neural decoders and train the post decoder
to be specialized for uncorrected words that the first decoder fails to
correct. Secondly, to address the vanishing gradient issue in training, we
introduce a block-wise training schedule that locally trains a block of weights
while retraining the preceding block. Lastly, we show that assigning different
weights to unsatisfied check nodes effectively lowers the error-floor with a
minimal number of weights. By applying these training methods to standard LDPC
codes, we achieve the best error-floor performance compared to other decoding
methods. The proposed NMS decoder, optimized solely through novel training
methods without additional modules, can be integrated into existing LDPC
decoders without incurring extra hardware costs. The source code is available
at https://github.com/ghy1228/LDPC_Error_Floor .Comment: 17 pages, 10 figure
Association Between MicroRNA196a2 rs11614913 Genotypes and the Risk of Non-Small Cell Lung Cancer in Korean Population
The Effect of Milrinone on the Right Ventriclular Function in Patients with Reduced Right Ventricular Function Undergoing Off-pump Coronary Artery Bypass Graft Surgery
This investigation evaluated the effect of continuous milrinone infusion on right ventriclular (RV) function during off-pump coronary artery bypass graft (OPCAB) surgery in patients with reduced RV function. Fifty patients scheduled for OPCAB, with thermodilution RV ejection fraction (RVEF) <35% after anesthesia induction, were randomly allocated to either milrinone (0.5 µg/kg/min) or control (saline) group. Hemodynamic variables and RV volumetric data measured by thermodilution method were collected as follows: after anesthesia induction (T1); 10 min after heart displacement for obtuse marginal artery anastomosis (T2); after pericardial closure (T3). Cardiac index and heart rate increased and systemic vascular resistance significantly decreased in milrinone group at T2. Initially lower RVEF of milrinone group was eventually comparable to control group after milrinone infusion. RVEF did not significantly change at T2 and T3 in both groups. RV end-diastolic volume in milrinone group consistently decreased from the baseline at T2 and T3. Continuous infusion of milrinone without a bolus demonstrated potentially beneficial effect on cardiac output and RV afterload in patients with reduced RV function during OPCAB. However, aggressive augmentation of intravascular volume seems to be necessary to maximize the effect of the milrinone in these patients
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