Safety, feasibility, and long-term results of percutaneous closure of atrial septal defects using the Amplatzer septal occluder without periprocedural echocardiography.

OBJECTIVES We sought to assess the safety and efficacy of percutaneous closure of atrial septal defects (ASDs) under fluoroscopic guidance only, without periprocedural echocardiographic guidance. BACKGROUND Percutaneous closure of ASDs is usually performed using simultaneous fluoroscopic and transthoracic, transesophageal (TEE), or intracardiac echocardiographic (ICE) guidance. However, TEE requires deep sedation or general anesthesia, which considerably lengthens the procedure. TEE and ICE increase costs. METHODS Between 1997 and 2008, a total of 217 consecutive patients (age, 38 ± 22 years; 155 females and 62 males), of whom 44 were children ≤16 years, underwent percutaneous ASD closure with an Amplatzer ASD occluder (AASDO). TEE guidance and general anesthesia were restricted to the children, while devices were implanted under fluoroscopic guidance only in the adults. For comparison of technical safety and feasibility of the procedure without echocardiographic guidance, the children served as a control group. RESULTS The implantation procedure was successful in all but 3 patients (1 child and 2 adults; 1.4%). Mean device size was 23 ± 8 mm (range, 4-40 mm). There was 1 postprocedural complication (0.5%; transient perimyocarditis in an adult patient). At last echocardiographic follow-up, 13 ± 23 months after the procedure, 90% of patients had no residual shunt, whereas a minimal, moderate, or large shunt persisted in 7%, 1%, and 2%, respectively. Four adult patients (2%) underwent implantation of a second device for a residual shunt. During a mean follow-up period of 3 ± 2 years, 2 deaths and 1 ischemic stroke occurred. CONCLUSION According to these results, percutaneous ASD closure using the AASDO without periprocedural echocardiographic guidance seems safe and feasible.

Long-term Responses of Mountain Ecosystems to Environmental Changes: Resilience, Adjustment, and Vulnerability

The steep environmental gradients of mountain ecosystems over short distances reflect large gradients of several climatic parameters and hence provide excellent possibilities for ecological research on the effects of environmental change. To gain a better understanding of the dynamics of abiotic and biotic parameters of mountain ecosystems, long-term records are required since permanent plots in mountain regions cover in the best case about 50 - 70 years. In order to extend investigations of ecological dynamics beyond these temporal limitations of permanent plots, paleoecological approaches can be used if the sampling resolution can be adapted to ecological research questions, e.g. a sample every 10 years. Paleoecological studies in mountain ecosystems can provide new ecological insights through the combination of different spatial and temporal scales. [f we thus improve our understanding of processes across both steep environmental gradients and different time scales, we may be able to better estimate ecosystem responses to current and future environmental change (Ammann et al. 1993; Lotter et al. 1997). The complexity of ecological interactions in mountain regions forces us to concentrate on a number of sub-systems - without losing sight of the wider context. Here, we summarize a few case studies on the effects of Holocene climate change and disturbance on the vegetation of the Western Alps. To categorize the main response modes of vegetation to climatic change and disturbance in the Alps we use three classes of ecological behaviour: "resilience", "adjustment", and "vulnerability", We assume a resilient (or elastic) behaviour if vegetation is able to recover to its former state, regaining important ecosystem characteristics, such as floristic composition, biodiversity, species abundances, and biomass (e.g. Küttel 1990; Aber and Melillo 199 1). Conversely, vegetation displacements may occur in response to climatic change and/or disturbance. In some cases, this may culminate in irreversible large-scale processes such as species and/or community extinctions. Such drastic developments indicate high ecosystem vulnerability (or inelasticity or instability, for detailed definitions see Küttel 1990; Aber and Melillo 199 1) to climatic change and/or disturbance. In this sense, the "vulnerability" (or instability) of an ecosystem is expressed by the degree of failure to recover to the original state before disturbance and/or climatic change. Between these two extremes (resilience vs. vulnerability), ecosystem adjustments to climatic change and/or disturbance may occur, including the appearance of new and/or the disappearance of old species. The term "adjustment" is hence used to indicate the response of vegetational communities, which adapted to new environmental conditions without losing their main character. For forest ecosystems, we assume vegetational adjustments (rather than vulnerability) if the dominant (or co-dominant) tree species are not outnumbered or replaced by formerly unimportant plant species or new invaders. Adaptation as a genetic process is not discussed here and will require additional pbylogeographical studies (that incorporate the analysis of ancient DNA) in order to fully understand the distributions of ecotypes.

Long-term Success of Family Firms: Investigating Specific Aspects of Firm-level Entrepreneurship and Individual-level Antecedents

Long-term success of family firms is of utmost social and economic importance. Three of its determinants are in the center of this Dissertation: firmlevel entrepreneurial orientation (EO), managers' entrepreneurial behavior, and value-creating attitudes of non-family employees. Each determinant and respective research gaps are addressed by one paper of this cumulative dissertation. Referring to firm-level EO, scholars claim that EO is a main antecedent to firms' both short- and long-term success. However, family firms seem to be successful across generations despite rather low levels of EO. The first paper addresses this paradox by investigating EO patterns of long-lived family firms in three Swiss case studies. The main finding is that the key to success is not to be as entrepreneurially as possible all the time, but to continuously adapt the EO profile depending on internal and external factors. Moreover, the paper suggest new subcategories to different EO dimensions. With regard to entrepreneurial behavior of managers, there is a lack of knowledge how individual-level and organizational level factors affect its evolvement. The second paper addresses this gap by investigating a sample of 403 middle-level managers from both family and non-family firms. It introduces psychological ownership of managers as individual-level antecedent and investigates the interaction with organizational factors. As a central insight, management support is found to strengthen the psychological ownership-entrepreneurial behavior relationship. The third paper is based on the fact that employees' justice perceptions are established antecedents of value-creating employee attitudes such as affective commitment and job satisfaction. Even though family firms are susceptible to nonfamily employees´ perceptions of injustice, corresponding research is scarce. Moreover, the mechanism connecting justice perceptions and positive outcomes is still unclear. Addressing these gaps, the analysis of a sample of 310 non-family employees reveals that psychological ownership is a mediator in the relationships between distributive justice perceptions and both affective commitment and job satisfaction. Altogether, the three papers offer valuable contributions to family business literature with respect to EO, entrepreneurial behavior, and value-creating employee attitudes. Thus, they increase current understanding about important determinants of family firms' long-term success, while opening up numerous ways of future research.

Daily monetary impulses and security prices

This paper uses Swiss data to study the real long-run effects of monetary policy. Daily unexpected changes in the monetary base are found to be negatively correlated with security price changes. This result is unaffected when, implicitly following Geske and Roll (1983), we try to measure the autonomous component of monetary policy by taking into account a reaction function of monetary policy to changes in real variables.