Do Transaction Costs and Risk Preferences Influence Marketing Arrangements in the Illinois Hog Industry?

Risk reduction and transaction costs are often used to explain contracting in the U.S. hog industry with little empirical support. Using a unified conceptual framework that draws from risk behavior and transaction cost theories, in combination with unique survey and accounting data, we demonstrate that risk preferences and asset specificity impact Illinois producers’ use of contracts and spot markets. In particular, producers’ investments in specific hog genetics and human capital are related to selection of long-term marketing contracts over spot markets. Producers who perceive greater levels of price risk and/or are more averse are more (less) likely to use contracts (spot markets). Key words: asset specificity, contracts, hogs, risk attitude, risk behavior, risk perception, transaction costs economic

Propagation of sound from aircraft ground operations

Atmospheric absorption effects on sound propagation losses during aircraft ground operation

The propagation of sound from airport ground operations

Noise measurements of sound propagation related to jet aircraft takeoff

HARMONIC GENERATION *

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72100/1/j.1749-6632.1965.tb20242.x.pd

Improved supplier selection and cost management for globalized automotive production

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Global Operations Program at MIT, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 74-75).For many manufacturing and automotive companies, traditional sourcing decisions rely on total landed cost models to determine the cheapest supplier. Total landed cost models calculate the cost to purchase a part plus all logistics costs to transport the part from the supplier to the plant. Although these models can provide a base comparison for suppliers, they do not contain the complete information necessary to make a supplier decision. There are several other factors that must be considered in the sourcing decision process to make a proper decision that considers the risks associated with supplier selection. The primary focus of the thesis is to improve the sourcing decision methodology for choosing between suppliers by identifying and developing models for the key elements in the decision process. A secondary focus of the project is to identify an inventory policy that reduces the supply chain cost of foreign suppliers. Four different aspects of the sourcing decisions process are discussed. The first section is the risk of air freight. Air freight risk is important in the context of the global versus local supplier discussion because it creates a major discrepancy when comparing the potential cost of each supplier. The thesis develops a model that provides an expected cost of air freight to measure air freight risk through the use of historical data. The second aspect discussed is the development of a more comprehensive cash flow model to determine the NPV of cash flows of each supplier that includes the impact of inventory policy and payment terms on net working capital. A more comprehensive model provides the true cash cost, not the accounting cost, of a supplier decision. The model is primarily used to compare local and foreign suppliers. The third part discussed is the impact of foreign exchange rates on the supplier decision and how certain assumptions can impact or alter the supplier decision. A means of testing how the supplier decision is impacted by foreign exchange assumptions and volatility is discussed. Finally, a dual mode sourcing model that ships parts by both air and ocean freight is developed to reduce overall logistics costs for parts procured from foreign suppliers.by Joseph P. Franken, II.S.M.M.B.A

Multiband Flanger

Architecture & Allied Art

The treatment of soft-tissue defects of the lower leg after a traumatic open tibial fracture

The treatment of large soft-tissue defects of the lower leg remains a challenge. The timing of the operation, the most suitable type of tissue, and the decision between local or free flap coverage still remains under discussion. Fifty-two patients were treated with local or free flap coverage after a traumatic soft-tissue defect of the lower leg. We compared the results after treatment with local versus free flaps and fasciocutaneous flaps versus musculocutaneous flaps. In the case of primary reconstruction, we also compared the results regarding the timing of the operation: patients treated within 72 h after the trauma versus patients treated after 72 h. Thirty-five patients (67%) have been treated because of posttraumatic soft-tissue defects and, therefore, insufficient fracture coverage. Seventeen patients (33%) were treated because of a chronic osteomyelitis that arose after the trauma. In our study, we did not find a statistically significant difference between the postoperative complications of local and free flaps. A significant increase could be demonstrated in the number of revisions after treatment with a free flap. Treatment with a fasciocutaneous flap in the entire study group was associated with significantly more postoperative complications than treatment with a musculocutaneous flap. There was no significant difference in results after early or late flap coverage. Patients treated with local or free flaps achieved equal outcomes, except for the number of postoperative revisions in which local flaps required lesser revisions. Treatment with a musculocutaneous flap is preferable to treatment with a fasciocutaneous flap regarding postoperative complications. The timing of operation proved not to be a discriminating factor

Twist1 Is a TNF-Inducible Inhibitor of Clock Mediated Activation of Period Genes.

BACKGROUND: Activation of the immune system affects the circadian clock. Tumor necrosis factor (TNF) and Interleukin (IL)-1β inhibit the expression of clock genes including Period (Per) genes and the PAR-bZip clock-controlled gene D-site albumin promoter-binding protein (Dbp). These effects are due to cytokine-induced interference of E-box mediated transcription of clock genes. In the present study we have assessed the two E-box binding transcriptional regulators Twist1 and Twist2 for their role in cytokine induced inhibition of clock genes. METHODS: The expression of the clock genes Per1, Per2, Per3 and of Dbp was assessed in NIH-3T3 mouse fibroblasts and the mouse hippocampal neuronal cell line HT22. Cells were treated for 4h with TNF and IL-1β. The functional role of Twist1 and Twist2 was assessed by siRNAs against the Twist genes and by overexpression of TWIST proteins. In luciferase (luc) assays NIH-3T3 cells were transfected with reporter gene constructs, which contain a 3xPer1 E-box or a Dbp E-box. Quantitative chromatin immunoprecipitation (ChIP) was performed using antibodies to TWIST1 and CLOCK, and the E-box consensus sequences of Dbp (CATGTG) and Per1 E-box (CACGTG). RESULTS: We report here that siRNA against Twist1 protects NIH-3T3 cells and HT22 cells from down-regulation of Period and Dbp by TNF and IL-1β. Overexpression of Twist1, but not of Twist2, mimics the effect of the cytokines. TNF down-regulates the activation of Per1-3xE-box-luc, the effect being prevented by siRNA against Twist1. Overexpression of Twist1, but not of Twist2, inhibits Per1-3xE-box-luc or Dbp-E-Box-luc activity. ChIP experiments show TWIST1 induction by TNF to compete with CLOCK binding to the E-box of Period genes and Dbp. CONCLUSION: Twist1 plays a pivotal role in the TNF mediated suppression of E-box dependent transactivation of Period genes and Dbp. Thereby Twist1 may provide a link between the immune system and the circadian timing system

In vivo imaging of the central and peripheral effects of sleep deprivation and suprachiasmatic nuclei lesion on PERIOD-2 protein in mice.

STUDY OBJECTIVES: That sleep deprivation increases the brain expression of various clock genes has been well documented. Based on these and other findings we hypothesized that clock genes not only underlie circadian rhythm generation but are also implicated in sleep homeostasis. However, long time lags have been reported between the changes in the clock gene messenger RNA levels and their encoded proteins. It is therefore crucial to establish whether also protein levels increase within the time frame known to activate a homeostatic sleep response. We report on the central and peripheral effects of sleep deprivation on PERIOD-2 (PER2) protein both in intact and suprachiasmatic nuclei-lesioned mice. DESIGN: In vivo and in situ PER2 imaging during baseline, sleep deprivation, and recovery. SETTINGS: Mouse sleep-recording facility. PARTICIPANTS: Per2::Luciferase knock-in mice. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Six-hour sleep deprivation increased PER2 not only in the brain but also in liver and kidney. Remarkably, the effects in the liver outlasted those observed in the brain. Within the brain the increase in PER2 concerned the cerebral cortex mainly, while leaving suprachiasmatic nuclei (SCN) levels unaffected. Against expectation, sleep deprivation did not increase PER2 in the brain of arrhythmic SCN-lesioned mice because of higher PER2 levels in baseline. In contrast, liver PER2 levels did increase in these mice similar to the sham and partially lesioned controls. CONCLUSIONS: Our results stress the importance of considering both sleep-wake dependent and circadian processes when quantifying clock-gene levels. Because sleep deprivation alters PERIOD-2 in the brain as well as in the periphery, it is tempting to speculate that clock genes constitute a common pathway mediating the shared and well-known adverse effects of both chronic sleep loss and disrupted circadian rhythmicity on metabolic health