Heinz Zimmermann

An Integrated Framework of Corporate Governance and Firm Valuation

Recent empirical research shows evidence of a positive relationship between the quality of firm-specific corporate governance and firm valuation. Instead of looking at one single corporate governance mechanism in isolation, we construct a broad corporate governance index and apply five additional variables related to ownership structure, board characteristics, and leverage to provide a comprehensive description of firm-level corporate governance for a representative sample of Swiss firms. To control for potential endogeneity of these six governance mechanisms, we develop a system of simultaneous equations and apply three-stage least squares (3SLS). Our results support the widespread hypothesis of a positive relationship between corporate governance and firm valuation.

Do we really need routine computed tomographic scanning in the primary evaluation of blunt chest trauma in patients with "normal" chest radiograph?

BACKGROUND A major cause of morbidity and mortality after blunt chest trauma remains undetected injuries. This study evaluates the role of routine computed tomographic (CT) scan. METHODS We studied 93 consecutive patients from January 1999 to July 2000: 73 (76.3%) after motor vehicle crash with crash speed > 10 mph, and 22 (23.7%) after fall from height > 5 ft. Simultaneous with initial clinical evaluation, anteroposterior chest radiograph and helical chest CT scan were obtained for all patients. RESULTS Sixty-eight patients (73.1%) showed at least one pathologic sign on chest radiograph, and 25 patients (26.9%) had normal chest radiograph. In 13 (52.0%) of these 25 patients, the CT scan showed multiple injuries; among these were two aortic lacerations, three pleural effusions, and one pericardial effusion. CONCLUSION Over 50% of patients with normal initial chest radiograph showed multiple injuries on the CT scan, among which were also two (8%) potentially fatal aortic lesions. We therefore recommend primary routine chest CT scan in all patients with major chest trauma.

A linear model for tracking error minimization

Abstract This article investigates four models for minimizing the tracking error between the returns of a portfolio and a benchmark. Due to linear performance fees of fund managers, we can argue that linear deviations give a more accurate description of the investors’ risk attitude than squared deviations. All models have in common that absolute deviations are minimized instead of squared deviations as is the case for traditional optimization models. Linear programs are formulated to derive explicit solutions. The models are applied to a portfolio containing six national stock market indexes (USA, Japan, UK, Germany, France, Switzerland) and the tracking error with respect to the MSCI (Morgan Stanley Capital International Index) world stock market index is minimized. The results are compared to those of a quadratic tracking error optimization technique. The portfolio weights of the optimized portfolio and its risk/return properties are different across the models which implies that optimization models should be targeted to the specific investment objective. Finally, it is shown that linear tracking error optimization is equivalent to expected utility maximization and lower partial moment minimization.

Reversibility of secondary biliary fibrosis by biliodigestive anastomosis in the rat

Biliary cirrhosis with portal hypertension and hepatocellular failure is a well-known complication of extrahepatic obstruction. It is unclear to what extent these changes are reversible by biliodigestive anastomosis. Therefore a rat model of relief of biliary obstruction was developed by performing Roux-en-Y choledochojejunostomy in rats after bile duct obstruction. Patency of the biliodigestive anastomosis was documented by biliary scintigraphy. Microsomal function was assessed in vivo by the aminopyrine breath test and portal hypertension by spleen pulp pressure. Microsomal function was markedly impaired in obstructed animals but recovered after biliodigestive anastomosis. Microsomal cytochrome P450 content paralleled these changes. Similarly, portal hypertension was reversed after successful relief of obstruction. Stereologic analysis showed that biliodigestive anastomosis partially reversed bile ductular proliferation and fibrosis. Studying the time course of recovery showed that restoration of microsomal function was achieved after 2 weeks whereas recovery from portal hypertension required 4 weeks of biliary drainage. Recovery of microsomal function was paralleled by normalization of microsomal lipid composition while resolution of portal hypertension occurred parallel to resolution of the histologic abnormalities.

Can RapidTEG accelerate the search for coagulopathies in the patient with multiple injuries

HYPOTHESIS Early recognition of coagulopathy may improve the care of patients with multiple injuries. Rapid thrombelastography (RapidTEG) is a new variant of thrombelastography (TEG), in which coagulation is initiated by the addition of protein tissue factor. The kinetics of coagulation and the times of measurement were compared for two variants of TEG--RapidTEG and conventional TEG, in which coagulation was initiated with kaolin. The measurements were performed on blood samples from 20 patients with multiple injuries. The RapidTEG results were also compared with conventional measurements of blood coagulation. The mean time for the RapidTEG test was 19.2 +/- 3.1 minutes (mean +/- SD), in comparison with 29.9 +/- 4.3 minutes for kaolin TEG and 34.1 +/- 14.5 minutes for conventional coagulation tests. The mean time for the RapidTEG test was 30.8 +/- 5.72 minutes, in comparison with 41.5 +/- 5.66 minutes for kaolin TEG and 64.9 +/- 18.8 for conventional coagulation tests---measured from admission of the patients to the resuscitation bay until the results were available. There were significant correlations between the RapidTEG results and those from kaolin TEG and conventional coagulation tests. RapidTEG is the most rapid available test for providing reliable information on coagulopathy in patients with multiple injuries. This has implications for improving patient care.

False positive staining in the TUNEL assay to detect apoptosis in liver and intestine is caused by endogenous nucleases and inhibited by diethyl pyrocarbonate.

BACKGROUND: The terminal transferase uridyl nick end labelling (TUNEL) assay allows the easy demonstration of cell death as a result of apoptosis. However, when this assay is applied to liver tissue, the number of TUNEL positive cells is dependent on the time of incubation with proteinase K. AIM: To test whether false positive results are the result of the release of endogenous endonucleases by proteinase K and can be abolished by pretreatment with diethyl pyrocarbonate (DEPC). METHODS: Involution of hyperplastic ductules in bile duct ligated rats after biliary decompression by Roux-en-Y anastomosis and acute CCl4 intoxication were studied as models of apoptosis and necrosis, respectively. A standard TUNEL assay was applied to formalin fixed tissue sections mounted with cement. To inhibit putative endogenous endonucleases, tissue slides were pre-incubated with DEPC. RESULTS: In the standard TUNEL assay, the number of positive nuclei was highly dependent upon the length of time that sections were incubated with proteinase K. After pretreatment with DEPC, only cells that also exhibited morphological features of apoptosis stained positive. DEPC pretreatment abolished false positive staining in CCl4 induced hepatocyte necrosis and blocked interference by endogenous alkaline phosphatase in intestine. The method of gluing the tissue section to the glass slide was found to be of utmost importance because the effect of DEPC was abolished on silanised slides. CONCLUSIONS: False positive staining in the TUNEL assay in the liver is caused by the release of endogenous endonucleases as a result of proteinase treatment. This can be abolished by pretreatment of tissue slides with DEPC.

Stock offerings in a different institutional setting: the Swiss case, 1973-1983

This paper analyzes the stock price effect of equity issues in Switzerland. There, insiders are not legally prevented from using their information for personal trades, and security offerings are with almost no exception rights issues. Unlike what we find for a comprehensive sample of U.S. rights issues and a sample of U.S. general cash offerings, a significant majority of firms experiences a positive monthly announcement effect. The average abnormal return itself, however, is not significant. Also, we find evidence inconsistent with infinitely price-elastic demand functions for common stock, as well as some evidence that offer prices convey new information.

The behavior of intra-daily exchange rates

Abstract The behavior of exchange rates is examined as they evolve continuously over time. The data consist of Swiss franc/U.S. dollar rates for nine days during the years 1978–1980 as quoted by a major Swiss dealer operating on the interbank market. Since this market is highly organized, the observations are market prices at the same time. The distributions of relative changes in exchange rates measured over one minute are highly leptokurtic. The normal distribution is rather rapidly approached when the measurement interval is lengthened from one up to ten minutes. Time series analysis reveals that the natural logarithms of exchange rates are adequately described by a random walk, the same stochastic process as has been found for daily, weekly, monthly and quarterly observations. For short time intervals, significant autocorrelations sometimes occur at the first few lags, which are, however, not stable enough over time to form a basis for reliable forecasts.

Characteristics, Symptoms, and Outcome of Severe Dysnatremias Present on Hospital Admission

OBJECTIVE Dysnatremias are common in critically ill patients and associated with adverse outcomes, but their incidence, nature, and treatment rarely have been studied systematically in the population presenting to the emergency department. We conducted a study in patients presenting to the emergency department of the University of Bern. METHODS In this retrospective case series at a university hospital in Switzerland, 77,847 patients admitted to the emergency department between April 1, 2008, and March 31, 2011, were included. Serum sodium was measured in 43,911 of these patients. Severe hyponatremia was defined as less than 121 mmol/L, and severe hypernatremia was defined as less than 149 mmol/L. RESULTS Hypernatremia (sodium>145 mmol/L) was present in 2% of patients, and hyponatremia (sodium<135 mmol/L) was present in 10% of patients. A total of 74 patients had severe hypernatremia, and 168 patients had severe hyponatremia. Some 38% of patients with severe hypernatremia and 64% of patients with hyponatremia had neurologic symptoms. The occurrence of symptoms was related to the absolute elevation of serum sodium. Somnolence and disorientation were the leading symptoms in hypernatremic patients, and nausea, falls, and weakness were the leading symptoms in hyponatremic patients. The rate of correction did not differ between symptomatic and asymptomatic patients. Patients with symptomatic hypernatremia showed a further increase in serum sodium concentration during the first 24 hours after admission. Corrective measures were not taken in 18% of hypernatremic patients and 4% of hyponatremic patients. CONCLUSIONS Dysnatremias are common in the emergency department. Hyponatremia and hypernatremia have different symptoms. Contrary to recommendations, serum sodium is not corrected more rapidly in symptomatic patients.

Long-term outcome in patients with mild traumatic brain injury: a prospective observational study.

BACKGROUND Mild traumatic brain injury (MTBI) is common; up to 37% of adult men have a history of MTBI. Complaints after MTBI are persistent headaches, memory impairment, depressive mood disorders, and disability. The reported short- and long-term outcomes of patients with MTBI have been inconsistent. We have now investigated long-term clinical and neurocognitive outcomes in patients with MTBI (at admission, and after 1 and 10 years). METHODS Patients of a previous study investigating MTBI short-term outcome were prospectively reassessed after ±10 year using the same standardized data entry form and validated questionnaire (Beltztest with Beltz Score [BeSc]) for evaluation of Quality of life (QoL) and neurocognitive outcome (higher scores indicate lower QoL). RESULTS Eighty-six of 176 patients (49%) could be reassessed (n = 75 lost to follow-up; n = 8 second brain trauma; n = 7 death), 10.4 ± 2 years after initial evaluation. Over time, overall BeSc was significantly increased (5.92 ± 10.3 [admission] vs. 10.7 ± 12.8 [1 year] vs. 20.86 ± 17.1 [10 year]; p < 0.0001); only 54 of 86 patients (62.8%) presented with a normal BeSc. Long-term complaints were fatigue, insomnia, and exhaustion. Ten of eighty-six patients (11.6%) had intracranial injury (ICI) and initial BeSc was almost twofold higher in patients with ICI than in patients without ICI (10.0 ± 8.4 vs. 5.3 ± 9.6; p = 0.007). This difference was not seen after 1 year or after 10 years (10.3 ± 11.6 vs. 10.3 ± 10.1 and 21.4 ± 17.3 vs. 16.1 ± 16.4, respectively). Eight of eighty-six patients (9.3%) lost their jobs because of persistent complaints after MTBI. CONCLUSION BeSc deteriorates over time; our data suggest a decline in general health and QoL in a substantial proportion of patients (37.2%) 10 years after MTBI. Patients without ICI appear to have a better long-term outcome with regard to subjective complaints and QoL.