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This article reports on the reaction of bone to a new family of nanocrystalline hydroxyapatite biomaterials with crystal sizes similar to those of human bone. Pure nanoapatite cylinders and organoapatite cylinders containing a synthetic nanopeptide were analyzed 28 days after implantation into the spongy bone of Chinchilla rabbits. The experimental techniques used for analysis were light microscopy, scanning electron microscopy, and transmission electron microscopy. Both implant types were well incorporated, and interface events were found to be similar to those observed on human bone surfaces with regard to resorption by osteoclast-like cells and bone formation by osteoblasts. Different types of giant cells were observed resorbing the outermost surfaces of implants. There seemed to be both dissolution of the implant and particulate biodegradation leading to less dense implant regions near the interface, whereas the bulk of the implants remained denser. Transmission electron micrographs revealed that bone bonding occurred with and without an afibrillar intervening layer. Given the biologic reaction observed, these implant materials should be suitable for bone replacement and the organoapatite form could be useful for additional functions such as the release of drugs and optimized release of antibiotics, growth factors, or other substances. The organic component can also be used to control physical properties in a bony implantation bed.

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This article describes a nonlinear frequency domain method for the simulation of unsteady blade row interaction problems across several blade rows in turbomachinery. The capability to efficiently simulate such interactions is crucial for the improvement of the prediction of blade vibrations, tonal noise, and the impact of unsteadiness on aerodynamic performance. The simulation technique presented here is based on the harmonic balance approach and has been integrated into an existing flow solver. A nontrivial issue in the application of harmonic balance methods to turbomachinery flows is the fact that various fundamental frequencies may occur simultaneously in one relative system, each one being due to the interaction of two blade rows. It is shown that, considering the disturbances corresponding to different fundamental frequencies as mutually uncoupled, one can develop an unsteady simulation method which from a practial view point turns out to be highly attractive. On the one hand, it is possible to take into account arbitrarily many nonlinear interaction terms. On the other, the computational efficiency can be increased considerably once it is known that the nonlinear coupling between certain subsets of the harmonics plays only a minor role. To validate the method and demonstrate its accuracy and efficiency a multistage compressor configuration is simulated using both the method described in this article and a conventional time-domain solver.

Carbohydrate-deficient transferrin (CDT) is reported to have a higher specificity in alcoholism than conventional markers. As the morbidity and mortality rates amongst chronic alcoholics are raised following trauma, the objective was to investigate if CDT could be used to predict prolonged intensive care unit (ICU) stay and an increased morbidity in patients with multiple injuries admitted to the ICU. In this prospective double-blind study, 66 traumatized male patients were transferred to the ICU following admission via the emergency room and operative management. Blood samples for CDT determination were taken upon admission to the emergency room, the ICU and on days 2 and 4 following admission. The patients were allocated a priori to two groups: high CDT group (CDT >20 U/l on admission to the emergency room) and low CDT group (CDT < or = 20 U/l). CDT values were determined by microanion-exchange chromatography and radioimmunoassay. Thirty-six patients had an elevated CDT value on admission to the emergency room. The high CDT group had a significantly prolonged ICU stay (median high CDT group: 13 davs; median low CDT group: 5 days). Major intercurrent complications, such as alcohol-withdrawal syndrome, tracheobronchitis, pneumonia, pancreatitis, sepsis, and congestive heart failure, were significantly increased in the high CDT group. The increased risk of pneumonia in the high CDT group may be related to the significantly increased period of mechanical ventilation. As high CDT values were associated with an increased risk of intercurrent complications and a prolonged ICU stay, it seems reasonable to use CDT as a marker in intensifying research work into preventing alcoholism-associated complications.

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QoL in patients with LAHNC receiving IMRT takes approximately 1 year to return to baseline; some domains remain compromised after 1 year. Although IMRT aims to maintain function and QoL, patients experience long-term dry mouth and sticky saliva, particularly following definitive IMRT. Patients should be counseled at the start of therapy to reduce disappointment with the pace of recovery.

The surface structure, in particular the surface roughness, and the surface chemistry of titanium implants influence their anchoring in bone. The aim of this study was to analyse metal-bone contact (MBC) after modification of the implant surface, using different materials for blasting. The surface modification of titanium was produced by blasting it with particles made of Al2O3 or bioceramics. The biological effects were then investigated experimentally using 27 rabbits, analysed after 7, 28 and 84 days after the implantation of titanium cylinders treated accordingly. The MBC showed a tendency for more bone after bioceramics were used as a blasting material, compared to Al2O3.