49 research outputs found
The fog of change: opacity and asperity in organizations
Initial architectural change in organizations often induces other subsequent changes, generating lengthy cascades of changes in subordinate units. This article extends a formal model of cascading organizational change by examining the implications for organizational change of the limited foresight of those who initiate such change about unit interconnections (structural opacity) and the normative restrictiveness imposed on architectural features by organizational culture (cultural asperity). Opacity leads actors to underestimate the lengths of periods of reorganization and the associated costs of change, thereby prompting them unwittingly to undertake changes with adverse consequences. Increased opacity and asperity lengthen the total time that the organization spends reorganizing and the associated opportunity costs; and the expected effect of an architectural change on mortality hazards increases with the intricacy of the organizational design, structural opacity, and the asperity of organizational culture. We illustrate the theory with an interpretation of the 1995 collapse of Baring Brothers Bank
Bentall procedure: quarter century of clinical experiences of a single surgeon
BACKGROUND: We retrospectively analyzed 25 years of experiences with the button Bentall procedure in patients with aortic root pathologies. Even though this procedure has become widespread, there are only a few very long term follow-ups available in the clinical literature, especially regarding single surgeon results. METHODS: Between 1988 and 2013, a total of 147 patients underwent the Bentall procedure by the same surgeon. Among them there were 62 patients with Marfan syndrome. At the time of the surgery the mean age was 46.5 +/- 17.6 years. The impact of surgical experience on long-term survival was evaluated using a cumulative sum analysis chart. RESULTS: The Kaplan-Meier estimated overall survival rates for the 147 patients were 91.8 +/- 2.3 %, 84.3 +/- 3.1 %, 76.3 +/- 4.9 % and 59.5 +/- 10.7 % at 1,5,10 and 20 years, respectively. Multivariate Cox regression analysis identified EuroSCORE II over 3 % (OR 4.245, 95 % CI, 1.739-10.364, p = 0.002), acute indication (OR 2.942, 95 % CI, 1.158-7.480, p = 0.023), use of deep hypothermic circulatory arrest (OR 3.267, 95 % CI, 1.283-8.323, p = 0.013), chronic kidney disease (OR 6.865, 95 % CI, 1.339-35.189, p = 0.021) and early complication (OR 3.134, 95 % CI, 1.246-7.883, p = 0.015) as significant risk factors for the late overall death. The survival rate for freedom from early complication was 94.3 +/- 2.2 %, 88.0 +/- 3.3 %, 82.9 +/- 4.7 % and 69.2 +/- 8.4 % at 1,5,10 and 20 years. The main pathological findings of the aortic wall were cystic medial degeneration in 75 %, fibrosis in 6 %, atherosclerosis in 13 % and no pathological alteration in 6 % of the samples. The overall survival rate was significantly lower in patients operated in first 15 years compared to patients operated in the last decade (log-rank p = 0.011). CONCLUSION: According to our long-term follow-up the Bentall operation provides an appropriate functional result by resolving the lesions of the ascending aorta. Based on our results, 25-30 operations done is necessary to gain such a level of confidence and experince to aquire better results on long-term survival. In addition, we discussed that there were no co-morbidities affecting on the survival of Marfan patients and prophylactic aortic root replacement ensures a longer survival among patients with Marfan syndrome
Possible extracardiac predictors of aortic dissection in Marfan syndrome
BACKGROUND: According to previous studies, aortic diameter alone seems to be insufficient to predict the event of aortic dissection in Marfan syndrome (MFS). Determining the optimal schedule for preventive aortic root replacement (ARR) aortic growth rate is of importance, as well as family history, however, none of them appear to be decisive. Thus, the aim of this study was to search for potential predictors of aortic dissection in MFS. METHODS: A Marfan Biobank consisting of 79 MFS patients was established. Thirty-nine MFS patients who underwent ARR were assigned into three groups based on the indication for surgery (dissection, annuloaortic ectasia and prophylactic surgery). The prophylactic surgery group was excluded from the study. Transforming growth factor-beta (TGF-beta) serum levels were measured by ELISA, relative expression of c-Fos, matrix metalloproteinase 3 and 9 (MMP-3 and -9) were assessed by RT-PCR. Clinical parameters, including anthropometric variables - based on the original Ghent criteria were also analyzed. RESULTS: Among patients with aortic dissection, TGF-beta serum level was elevated (43.78 +/- 6.51 vs. 31.64 +/- 4.99 ng/l, p < 0.0001), MMP-3 was up-regulated (Ln2alpha = 1.87, p = 0.062) and striae atrophicae were more common (92% vs. 41% p = 0.027) compared to the annuloaortic ectasia group. CONCLUSIONS: We found three easily measurable parameters (striae atrophicae, TGF-beta serum level, MMP-3) that may help to predict the risk of aortic dissection in MFS. Based on these findings a new classification of MFS, that is benign or malignant is also proposed, which could be taken into consideration in determining the timing of prophylactic ARR
The effects of acute and elective cardiac surgery on the anxiety traits of patients with Marfan syndrome
BACKGROUND: Marfan syndrome is a genetic disease, presenting with dysfunction of connective tissues leading to lesions in the cardiovascular and skeletal muscle system. Within these symptoms, the most typical is weakness of the connective tissue in the aorta, manifesting as aortic dilatation (aneurysm). This could, in turn, become annuloaortic ectasia, or life-threatening dissection. As a result, life-saving and preventative cardiac surgical interventions are frequent among Marfan syndrome patients. Aortic aneurysm could turn into annuloaortic ectasia or life-threatening dissection, thus life-saving and preventive cardiac surgical interventions are frequent among patients with Marfan syndrome. We hypothesized that patients with Marfan syndrome have different level of anxiety, depression and satisfaction with life compared to that of the non-clinical patient population. METHODS: Patients diagnosed with Marfan syndrome were divided into 3 groups: those scheduled for prophylactic surgery, those needing acute surgery, and those without need for surgery (n = 9, 19, 17, respectively). To examine the psychological features of the patients, Spielberger's anxiety (STAI) test, Beck's Depression questionnaire (BDI), the Berne Questionnaire of Subjective Well-being, and the Satisfaction with Life scale were applied. RESULTS: A significant difference was found in trait anxiety between healthy individuals and patients with Marfan syndrome after acute life-saving surgery (p 0.1). Finally, a significant, medium size effect was found between patient groups on the Joy in Living scale (F (2.39) = 3.51, p = 0.040, eta2 = 0.15). CONCLUSIONS: Involving psychiatric and mental-health care, in addition to existing surgical treatment interventions, is essential for more successful recovery of patients with Marfan syndrome
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Holier than thou? Identity buffers and adoption of controversial practices in the Islamic banking category
Existing scholarship on categories frequently highlights how some category members may violate codes that others diligently abide by. In this paper, we take into account the differences in identity across category members, and ask how these relative differences determine their response to a code-violating change. Taking a case where category members are clearly identified as ‘insiders’
and ‘outsiders’, we argue that insiders’ reaction to a code violation depends upon the extent to which they believe their identity to be distinct from the code violator’s, who might be an insider or an outsider. Specifically, we suggest that it is the presence or absence of an ‘identity buffer’ – i.e., a relative identity advantage – which determines insiders’ reaction. We hypothesize that when a code violation is introduced by a fellow category insider, the focal insider will be more likely to refrain from the practice. When it is an outsider who introduces the code violation, insiders will be more likely to adopt the code violation as long as they can retain an identity buffer. We further posit that when outsiders adopt code-preserving behavior, thus narrowing the identity buffer between insiders and outsiders, it will mitigate insiders’ likelihood of code violation adoption. We test and find support for our hypotheses using data on Islamic banking industry in 12 countries (2003-2014)