Hypersomnia associated with bilateral posterior hypothalamic lesion - A polysomnographic case study

We examined an obese 58-year-old patient with a bilateral posterior hypothalamic lesion of unknown etiology. A 24-hour polysomnography revealed a markedly increased total sleep time (17.6 h). During daytime, only 3 continuous wake phases occurred. REM periods occurred only between 5 p.m. and 6 a.m. We conclude from our results that, similar to the results from animal experiments, the posterior hypothalamus in humans plays a critical role in the maintenance of wakefulness. Copyright (C) 2003 S. Karger AG, Basel

On the Formation of Eutectics in Variations of the Al10Co25Cr8Fe15Ni36Ti6 Compositionally Complex Alloy

Superalloy inspired Al10Co25Cr8Fe15Ni36Ti6 compositionally complex alloy is known for its c c microstructure and the third Heusler phase. Variations of this alloy, gained by replacing 0.5 or 1 at. pct Al by the equivalent amount of Mo, W, Zr, Hf or B, can show more phases in addition to this three phase morphology. When the homogenization temperature is chosen too high, a eutectic phase formation can take place at the grain boundaries, depending on the trace elements Mo and W do not form eutectics while Hf, Zr and B do. In order to avoid the eutectic formation and the potential implied grain boundary weakening, the homogenization temperature must be chosen carefully by differential scanning calorimetry measurements. A too low homogenization temperature, however, could impede the misorientation alignment of the dendrites in the grain. The influence of grain boundary phases and incomplete dendrite re orientation are compared and discusse

Consumer Shopping Costs as a Cause of Slotting Fees: A Rent-Shifting Mechanism

Analyzing a sequential bargaining framework with one retailer and two suppliers of substitutable goods, we show that slotting fees may emerge as a result of a rent-shifting mechanism when consumer shopping costs are taken into account. If consumers economize on their shopping costs by bundling their purchases, their buying decision depends rather on the price for the whole shopping basket than on individual product prices. This induces complementarities between the goods offered at a retail outlet. If the complementarity effect resulting from shopping costs dominates the original substitution effect, the wholesale price negotiated with the first supplier is upward distorted in order to shift rent from the second supplier. As long as the first supplier has only little bargaining power, she compensates the retailer for the upward distorted wholesale price by paying a slotting fee. We also show that banning slotting fees causes per- unit price to fall and welfare to increase

Collusive Effects of a Monopolist's Use of an Intermediary to Deliver to Retailers

A manufacturer contracting secretly with several downstream competitors faces an opportunism problem, preventing it from exerting its market power. In an infinitely repeated game, the opportunism problem can be relaxed. We show that the upstream firm's market power can be restored even further if the upstream firm chooses a mixed distribution system in which it makes use of an intermediary to distribute the good to a subset of the retailers and delivers directly only to the remaining downstream firms

Reestablishing Stability and Avoiding a Credit Crunch: Comparing Different Bad Bank Schemes

This paper develops a model to analyze two different bad bank schemes, an outright sale of toxic assets to a state-owned bad bank and a repurchase agreement between the bad bank and the initial bank. For both schemes, we derive a critical transfer payment that induces a bank manager to participate. Participation improves the bank's solvency and enables the bank to grant new loans. Therefore, both schemes can reestablish stability and avoid a credit crunch. However, an outright sale will be less costly to taxpayers than a repurchase agreement only if the transfer payment is sufficiently low

Cardiac Inflammation Contributes to Changes in the Extracellular Matrix in Patients With Heart Failure and Normal Ejection Fraction

Background-The pathophysiology of heart failure with normal ejection fraction (HFNEF) is still under discussion. Here we report the influence of cardiac inflammation on extracellular matrix (ECM) remodeling in patients with HFNEF. Methods and Results-We investigated left ventricular systolic and diastolic function in 20 patients with HFNEF and 8 control patients by conductance catheter methods and echocardiography. Endomyocardial biopsy samples were also obtained, and ECM proteins as well as cardiac inflammatory cells were investigated. Primary human cardiac fibroblasts were outgrown from the endomyocardial biopsy samples to investigate the gene expression of ECM proteins after stimulation with transforming growth factor-beta. Diastolic dysfunction was present in the HFNEF patients compared with the control patients. In endomyocardial biopsy samples from HFNEF patients, we found an accumulation of cardiac collagen, which was accompanied by a decrease in the major collagenase system (matrix metalloproteinase-1) in the heart. Moreover, a subset of inflammatory cells, which expressed the profibrotic growth factor transforming growth factor-beta, could be documented in the HFNEF patients. Stimulation of primary human cardiac fibroblasts from HFNEF patients with transforming growth factor-beta resulted in transdifferentiation of fibroblasts to myofibroblasts, which produced more collagen and decreased the amount of matrix metalloproteinase-1, the major collagenase in the human heart. A positive correlation between cardiac collagen, as well as the amount of inflammatory cells, and diastolic dysfunction was evident and suggests a direct influence of inflammation on fibrosis triggering diastolic dysfunction. Conclusions-Cardiac inflammation contributes to diastolic dysfunction in HFNEF by triggering the accumulation of ECM. (Circ Heart Fail. 2011;4:44-52.)Cardiac Dysfunction and Arrhythmia