Managerial work roles of health care executives in the changing environment of academic medical centers

The current U.S. health care system faces numerous environmental challenges. To compete and survive, health care organizations are developing strategies to lower costs and increase efficiency and quality. All of these strategies require rapid and precise decision making by top level managers. The purpose of this study is to determine the relationship between the environment, made up of unfavorable market conditions and limited resources, and the work roles of top level managers, specifically in the settings of academic medical centers. Managerial work roles are based on the ten work roles developed by Henry Mintzberg, in his book, The Nature of Managerial Work (1973). ^ This research utilized an integrated conceptual framework made up of systems theory in conjunction with role, attribution and contingency theories to illustrate that four most frequently performed Mintzberg's work roles are affected by the two environment dimensions. The study sample consisted of 108 chief executive officers in academic medical centers throughout the United States. The methods included qualitative methods in the form of key informants and case studies and quantitative in the form of a survey questionnaire. Research analysis involved descriptive statistics, reliability tests, correlation, principal component and multivariate analyses. ^ Results indicated that under the market condition of increased revenue based on capitation, the work roles increased. In addition, under the environment dimension of limited resources, the work roles increased when uncompensated care increased while Medicare and non-government funding decreased. ^ Based on these results, a typology of health care managers in academic medical centers was created. Managers could be typed as a strategy-formulator, relationship-builder or task delegator. Therefore, managers who ascertained their types would be able to use this knowledge to build their strengths and develop their weaknesses. Furthermore, organizations could use the typology to identify appropriate roles and responsibilities of managers for their specific needs. Consequently, this research is a valuable tool for understanding health care managerial behaviors that lead to improved decision making. At the same time, this could enhance satisfaction and performance and enable organizations to gain the competitive edge . ^

Social network structure as a critical success condition for open source software project communities

In recent years, a surprising new phenomenon has emerged in which globally-distributed online communities collaborate to create useful and sophisticated computer software. These open source software groups are comprised of generally unaffiliated individuals and organizations who work in a seemingly chaotic fashion and who participate on a voluntary basis without direct financial incentive. ^ The purpose of this research is to investigate the relationship between the social network structure of these intriguing groups and their level of output and activity, where social network structure is defined as (1) closure or connectedness within the group, (2) bridging ties which extend outside of the group, and (3) leader centrality within the group. Based on well-tested theories of social capital and centrality in teams, propositions were formulated which suggest that social network structures associated with successful open source software project communities will exhibit high levels of bridging and moderate levels of closure and leader centrality. ^ The research setting was the SourceForge hosting organization and a study population of 143 project communities was identified. Independent variables included measures of closure and leader centrality defined over conversational ties, along with measures of bridging defined over membership ties. Dependent variables included source code commits and software releases for community output, and software downloads and project site page views for community activity. A cross-sectional study design was used and archival data were extracted and aggregated for the two-year period following the first release of project software. The resulting compiled variables were analyzed using multiple linear and quadratic regressions, controlling for group size and conversational volume. ^ Contrary to theory-based expectations, the surprising results showed that successful project groups exhibited low levels of closure and that the levels of bridging and leader centrality were not important factors of success. These findings suggest that the creation and use of open source software may represent a fundamentally new socio-technical development process which disrupts the team paradigm and which triggers the need for building new theories of collaborative development. These new theories could point towards the broader application of open source methods for the creation of knowledge-based products other than software. ^

Carbon isotopic composition of cypress trees from South Florida and changing hydrologic condition

δ13C values were determined from cypresstree rings from two different study areas in SouthFlorida. One site is located in the Southeastern Everglades Marsh, where pond cypress (Taxodium ascendens) was sampled from tree islands (annual tree rings from 1970 to 2000). Bald cypress (Taxodium distichum) trees were sampled at the other site, located along the Loxahatchee River in a coastal wetland (decadal tree rings from 1830 to 1990). The isotopic time series from both sites display different, location-specific information. The pond cypressisotopic time series has a positive correlation with the total amount of annual precipitation, while the bald cypress data from the Loxahatchee River study area had two different records dependent on the level of saltwater stress. In general, for terrestrial trees growing in a temperate environment, water stress causes an increase in water-use efficiency (WUE) resulting in a relative 13C enrichment. Yet, trees growing in wetland settings in some cases do not respond in the same manner. We propose a conceptual model based on changes in carbon assimilation and isotopic fractionation as controlled by differences in stomatal resistance (water stress) and mesophyll resistance (biochemical and nutrient related) to explain the isotopic records from both sites. With further work and a longer time series, our approach may be tested, and used to reconstruct change in hydroperiods further back in time, and potentially provide a baseline for wetland restoration.

Social Network Structure as a Critical Success Condition for Open Source Software Project Communities

In recent years, a surprising new phenomenon has emerged in which globally-distributed online communities collaborate to create useful and sophisticated computer software. These open source software groups are comprised of generally unaffiliated individuals and organizations who work in a seemingly chaotic fashion and who participate on a voluntary basis without direct financial incentive. The purpose of this research is to investigate the relationship between the social network structure of these intriguing groups and their level of output and activity, where social network structure is defined as 1) closure or connectedness within the group, 2) bridging ties which extend outside of the group, and 3) leader centrality within the group. Based on well-tested theories of social capital and centrality in teams, propositions were formulated which suggest that social network structures associated with successful open source software project communities will exhibit high levels of bridging and moderate levels of closure and leader centrality. The research setting was the SourceForge hosting organization and a study population of 143 project communities was identified. Independent variables included measures of closure and leader centrality defined over conversational ties, along with measures of bridging defined over membership ties. Dependent variables included source code commits and software releases for community output, and software downloads and project site page views for community activity. A cross-sectional study design was used and archival data were extracted and aggregated for the two-year period following the first release of project software. The resulting compiled variables were analyzed using multiple linear and quadratic regressions, controlling for group size and conversational volume. Contrary to theory-based expectations, the surprising results showed that successful project groups exhibited low levels of closure and that the levels of bridging and leader centrality were not important factors of success. These findings suggest that the creation and use of open source software may represent a fundamentally new socio-technical development process which disrupts the team paradigm and which triggers the need for building new theories of collaborative development. These new theories could point towards the broader application of open source methods for the creation of knowledge-based products other than software.