Does Trauma Impair Self-Control? Differences in Delaying Gratification Between Former Indentured Child Laborers and Nontraumatized Controls.

Traumatic experiences may affect an individual's ability to exercise self-control, which is an essential characteristic for successfully managing life. As a measure of self-control, we used the delay discounting paradigm, that is, the extent to which a person devalues delayed gratification. The aim of this study was to investigate the relationship between childhood trauma and delay discounting using a control group design with elderly participants with a mean age of 76.2 years. Swiss former indentured child laborers (n=103) who had been exposed to trauma during their childhood were compared with nontraumatized controls (n=50). The trauma exposure group showed a considerably higher preference for immediate smaller rewards than the controls, indicating their lower self-control. A hierarchical regression analysis revealed that a history of abuse, current self-efficacy, and education were significantly associated with delay discounting. Implications for future research are discussed.

Zirconia-Based Screw-Retained Prostheses Supported by Implants: A Retrospective Study on Technical Complications and Failures

BACKGROUND Little information is yet available on zirconia-based prostheses supported by implants. PURPOSE To evaluate technical problems and failures of implant-supported zirconia-based prostheses with exclusive screw-retention. MATERIAL AND METHODS Consecutive patients received screw-retained zirconia-based prostheses supported by implants and were followed over a time period of 5 years. The implant placement and prosthetic rehabilitation were performed in one clinical setting, and all patients participated in the maintenance program. The treatment comprised single crowns (SCs) and fixed dental prostheses (FDPs) of three to 12 units. Screw-retention of the CAD/CAM-fabricated SCs and FDPs was performed with direct connection at the implant level. The primary outcome was the complete failure of zirconia-based prostheses; outcome measures were fracture of the framework or extensive chipping resulting in the need for refabrication. A life table analysis was performed, the cumulative survival rate (CSR) calculated, and a Kaplan-Meier curve drawn. RESULTS Two hundred and ninety-four implants supported 156 zirconia-based prostheses in 95 patients (52 men, 43 women, average age 59.1 ± 11.7 years). Sixty-five SCs and 91 FDPs were identified, comprising a total of 441 units. Fractures of the zirconia framework and extensive chipping resulted in refabrication of nine prostheses. Nearly all the prostheses (94.2%) remained in situ during the observation period. The 5-year CSR was 90.5%, and 41 prostheses (14 SCs, 27 FDPs) comprising 113 units survived for an observation time of more than 5 years. Six SCs exhibited screw loosening, and polishing of minor chipping was required for five prostheses. CONCLUSIONS This study shows that zirconia-based implant-supported fixed prostheses exhibit satisfactory treatment outcomes and that screw-retention directly at the implant level is feasible.

Observations of the Sensitivity of Beam Attenuation to Particle Size in a Coastal Bottom Boundary Layer

The goal of this study was to test the hypothesis that the aggregated state of natural marine particles constrains the sensitivity of optical beam attenuation to particle size. An instrumented bottom tripod was deployed at the 12-m node of the Martha's Vineyard Coastal Observatory to monitor particle size distributions, particle size-versus-settling-velocity relationships, and the beam attenuation coefficient (c(p)) in the bottom boundary layer in September 2007. An automated in situ filtration system on the tripod collected 24 direct estimates of suspended particulate mass (SPM) during each of five deployments. On a sampling interval of 5 min, data from a Sequoia Scientific LISST 100x Type B were merged with data from a digital floc camera to generate suspended particle volume size distributions spanning diameters from approximately 2 mu m to 4 cm. Diameter-dependent densities were calculated from size-versus-settling-velocity data, allowing conversion of the volume size distributions to mass distributions, which were used to estimate SPM every 5 min. Estimated SPM and measured c(p) from the LISST 100x were linearly correlated throughout the experiment, despite wide variations in particle size. The slope of the line, which is the ratio of c(p) to SPM, was 0.22 g m(-2). Individual estimates of c(p):SPM were between 0.2 and 0.4 g m(-2) for volumetric median particle diameters ranging from 10 to 150 mu m. The wide range of values in c(p):SPM in the literature likely results from three factors capable of producing factor-of-two variability in the ratio: particle size, particle composition, and the finite acceptance angle of commercial beam-transmissometers.

Technical Efficiency and Stock Market Reaction to Horizontal Mergers

This study examines the relationship between stock market reaction to horizontal merger announcements and technical efficiency levels of the participating firms. The analysis is based on data pertaining to eighty mergers between firms in the U.S. manufacturing industry during the 1990s. We employ Data Envelopment Analysis (DEA) to measure technical efficiency, which capture the firms. competence to produce the maximum output given certain productive resources. Abnormal returns related to the merger announcements provide the investor.s re-evaluation on the future performance of the participating firms. In order to avoid the problem of nonnormality, heteroskedasticity in the regression analysis, bootstrap method is employed for estimations and inferences. We found that there is a significant relationship between technical efficiency and market response. The market apparently welcomes the merger as an arrangement to improve resource utilizations.

A Review of Helium Hamiltonians

Helium Hamiltonian transformations are discussed in extreme detail.

Women in Eighteenth Century London: Female Coming of Age in Frances Burney’s Evelina, Cecilia, and The Witlings

The late eighteenth-century author Frances Burney is best known for popularizing the “comedy of manners,” a literary style later adopted by Jane Austen. Burney’s novels, journals, and plays offer an intriguing commentary on contemporary social customs and etiquette. In particular, she voices the concerns and desires of women, leading scholars to focus on the feminist overtones of her writing. Although she carefully examined female roles in the household and family structure, Burney also provided an insider’s perspective into London high life. As an acclaimed author and member of the royal court, Burney offers a rare insight into the lives of the urban elite. For these reasons, I have chosen to examine three of her works within the context of their London setting. In Evelina, Cecilia, and The Witlings, Burney examines women’s struggle for independence against the backdrop of the city. These works offer a new interpretation of the female Bildungsroman, or coming of age story. Burney shows how London life influences her heroines’ expectations, ambitions and desires. Evelina’s coming of age centers around the quest for family and social acceptance, while the two Cecilias of Cecilia and The Witlings confront the financial pressures that accompany their inheritance. Ultimately, the three protagonists learn important lessons that are specific to city life. Although Burney concludes each story with the heroine’s marriage, her focus is not on romance, as has been suggested, but on the cultural landscape of the city. Coming of age in her stories is inextricably connected to the diverse challenges and opportunities presented to urban women.

Fertilizer and Swine Manure Management Systems Impacts on Phosphorus in Soil and Subsurface Tile Drainage

Swine manure and fertilizer can be used to supply the nitrogen (N) and phosphorus (P) needs of crops. Excess P application sometimes applied with N-based manure for corn increases the risk of P loss and water quality impairment. Poor water quality in Iowa streams and lakes due to excess P has prompted questions about the impact of cropping and nutrient management systems on P loss from fields.