Land use effects on soil carbon fractions in the southeastern United States. I. Management-intensive versus extensive grazing

Changes in grassland management intended to increase productivity can lead to sequestration of substantial amounts of atmospheric C in soils. Management-intensive grazing (MiG) can increase forage production in mesic pastures, but potential impacts on soil C have not been evaluated. We sampled four pastures (to 50 cm depth) in Virginia, USA, under MiG and neighboring pastures that were extensively grazed or bayed to evaluate impacts of grazing management on total soil organic C and N pools, and soil C fractions. Total organic soil C averaged 8.4 Mg C ha(-1) (22%) greater under MiG; differences were significant at three of the four sites examined while total soil N was greater for two sites. Surface (0-10 cm) particulate organic matter (POM) C increased at two sites; POM C for the entire depth increment (0-50 cm) did not differ significantly between grazing treatments at any of the sites. Mineral-associated C was related to silt plus clay content and tended to be greater under MiG. Neither soil C:N ratios, POM C, or POM C:total C ratios were accurate indicators of differences in total soil C between grazing treatments, though differences in total soil C between treatments attributable to changes in POM C (43%) were larger than expected based on POM C as a percentage of total C (24.5%). Soil C sequestration rates, estimated by calculating total organic soil C differences between treatments (assuming they arose from changing grazing management and can be achieved elsewhere) and dividing by duration of treatment, averaged 0.41 Mg C ha(-1) year(-1) across the four sites.

Factors that influence Information Systems decisions and outcomes: A summary of key themes from four case studies" (2006). ACIS 2006 Proceedings. Paper 43.

This paper reports a summary of key findings from an examination of Information Systems decision making in four organisations. The study focused on what factors influenced decision makers during the critical preimplementation phase of Information Systems projects when systems were evaluated, selected and acquired. Using data gathered from interviews and organisational documentation, a critical hermeneutic analysis was performed in order to build an understanding of how informational and contextual influences acted on decision makers. Eight broad themes of factors were identified as having influence on decision makers and outcomes.

Clergy Sexual Abuse Litigation: Survivors Seeking Justice By Jennifer M. Balboni (Boulder: First Forum Press, 2011, 180pp. £43.77)

Balboni identifies her interest as being the processes of official disclosure and the path taken to civil litigation by survivors of child sexual abuse by Roman Catholic Clergy. The empirical data, on which this work is based, come in the form of in-depth face-to-face interviews with 22 survivors of clergy sexual abuse who have pursued litigation and 13 of their advocates. Balboni provides a space for survivors’ accounts of the ‘why’ behind their decision making and the impact of civil litigation on their lives to be heard, discussed and contextualized with both clarity and sensitivity. She acknowledges the breadth and depth of survivor responses, and the perspectives of their legal advocates, employing defiance theory, symbolic interaction and other points of analysis, to capture the journey of survivors towards litigation and beyond. Balboni’s work is deeply poignant in its recognition of survivors’ voices, the complex transformative capacity of litigation, the effects of community forming amongst survivors and the complex nature of ‘empowerment’ obtained by survivors through civil litigation. Acknowledging that, for many survivors, litigation becomes a means of identity change and truth telling, Balboni admits that ‘these survivors helped me understand that litigation is more about voice than monetary settlement’ (p. 149). This work is not deeply analytical or theoretically rich but privileges the voices of survivors and their advocates with sufficient frameworks to contextualize and explain participants’ perspectives and experiences.

The antigen 43 structure reveals a molecular velcro-like mechanism of autotransporter-mediated bacterial clumping

Aggregation and biofilm formation are critical mechanisms for bacterial resistance to host immune factors and antibiotics. Autotransporter (AT) proteins, which represent the largest group of outer-membrane and secreted proteins in Gram-negative bacteria, contribute significantly to these phenotypes. Despite their abundance and role in bacterial pathogenesis, most AT proteins have not been structurally characterized, and there is a paucity of detailed information with regard to their mode of action. Here we report the structure–function relationships of Antigen 43 (Ag43a), a prototypic self-associating AT protein from uropathogenic Escherichia coli. The functional domain of Ag43a displays a twisted L-shaped β-helical structure firmly stabilized by a 3D hydrogen-bonded scaffold. Notably, the distinctive Ag43a L shape facilitates self-association and cell aggregation. Combining all our data, we define a molecular “Velcro-like” mechanism of AT-mediated bacterial clumping, which can be tailored to fit different bacterial lifestyles such as the formation of biofilms.

Focus on opportunities as a mediator of the relationships between age, job complexity, and work performance

Focus on opportunities is a cognitive-motivational facet of occupational future time perspective that describes how many new goals, options, and possibilities individuals expect to have in their personal work-related futures. This study examined focus on opportunities as a mediator of the relationships between age and work performance and between job complexity and work performance. In addition, it was expected that job complexity buffers the negative relationship between age and focus on opportunities and weakens the negative indirect effect of age on work performance. Results of mediation, moderation, and moderated mediation analyses with data collected from 168 employees in 41 organizations (mean age = 40.22 years, SD = 10.43, range = 19-64 years) as well as 168 peers providing work performance ratings supported the assumptions. The findings suggest that future studies on the role of age for work design and performance should take employees' focus on opportunities into account.