Thin‐film transistor mobility limits considerations

The mobility limiting scattering mechanisms for amorphous semiconductors and polar polycrystalline semiconductors are studied in the context of developing new high‐performance thin‐film transistor (TFT) channel layer materials for large‐area electronics. A physics‐based model for carrier transport in an amorphous semiconductor is developed to estimate the mobility limits of amorphous semiconductor TFTs. The model involves band tail state trapping of a diffusive mobility. Simulation reveals a strong dependence on the band tail density of states. This consideration makes it difficult to realize a high‐performance p‐type oxide TFT. A polar crystalline semiconductor may offer a higher mobility but is fundamentally limited by polar optical phonon scattering. Any crystalline TFT channel layer for practical large‐area applications will not be a single crystal but polycrystalline, and therefore, grain size and grain boundary‐dependent scattering will further degrade the transport properties.     

From research to practice: the effects of the jointly sponsored dissemination of an arthritis self-care nursing intervention

Various educational programs have been developed and found to be effective in the self-management of arthritis. This study reexamined the effectiveness of one such program, "Bone Up On Arthritis" (BUOA), when the program was delivered by a community-based service organization to a sample of persons (N = 154) who differed widely in disease type and demographic characteristics. Arthritis Foundation staff implemented BUOA at four national sites; data were collected and analyzed by University of Michigan nurse researchers. Investigators found improved scores on all outcome measures (self-care behavior, helplessness, pain, dysfunction, and depression). These findings suggest that "Bone Up" is an effective nursing intervention in multiple organizational and community environments and for diverse patient populations.     

On the simulation,economic analysis,and life cycle assessment of batch-mode organic solvent recovery alternatives for the pharmaceutical industry

This study explores design alternatives for the purification and possible reuse of low-volume organic solvents waste streams in pharmaceutical manufacturing. Solvent use has a large impact on the life cycle of pharmaceutical processes, as typically 80–90% of the total mass used in the production of an active pharmaceutical ingredient is attributed to solvent use. Solvents are not consumed in pharmaceutical processes so they exit the process as waste. These waste streams are usually disposed of using incineration; therefore, generating significant life cycle emissions from disposal and replacement of virgin solvent. Solvent recovery efforts are generally limited to large-volume waste streams. However, results show that solvents in low-volume streams can also be economically recovered using a versatile multi-campaign solvent recovery skid. Three different solvent waste streams were evaluated, and 85.3% reduction in total emissions and 86.3% reduction in operating costs were achieved. Investment in the solvent recovery system was determined to have a payback period of 4.5 years and a 28% IRR over 10 years. A life cycle impact assessment shows impacts on the human health, ecosystems, and resources categories have been reduced by 82.4, 85.1, and 87.1%, respectively.     

Genomewide search for dehydrated hereditary stomatocytosis (hereditary xerocytosis): mapping of locus to chromosome 16 (16q23-qter)

Dehydrated hereditary stomatocytosis, also known as "hereditary xerocytosis," is caused by a red blood cell-membrane defect characterized by stomatocytic morphology, increased mean corpuscular hemoglobin concentration, decreased osmotic fragility, increased permeability to the univalent cations Na+ and K+, and an increased proportion of phosphatidylcholine in the membrane. The clinical presentation is heterogeneous, ranging from mild to moderate hemolytic anemia associated with scleral icterus, splenomegaly, and choletithiasis. Iron overload may develop later in life. The disease is transmitted as an autosomal dominant trait. We recruited a large three-generation Irish family affected with DHS and comprising 23 members, of whom 14 were affected and 9 were healthy. Two additional, small families also were included in the study. The DNA samples from the family members were used in a genomewide search to identify, by linkage analysis, the DHS locus. After the exclusion of a portion of the human genome, we obtained conclusive evidence for linkage of DHS to microsatellite markers on the long arm of chromosome 16 (16q23-q24). A maximum two-point LOD score of 6.62 at recombination fraction .00 was obtained with marker D16S520. There are no recombination events defining the telomeric limit of the region, which therefore is quite large. No candidate genes map to this area.     

Comparison of two novel MRAS based strategies for identifying parameters in permanent magnet synchronous motors

Two model reference adaptive system (MRAS) estimators are developed for identifying the parameters of permanent magnet synchronous motors (PMSM) based on the Lyapunov stability theorem and the Popov stability criterion, respectively. The proposed estimators only need online measurement of currents, voltages, and rotor speed to effectively estimate stator resistance, inductance, and rotor flux-linkage simultaneously. The performance of the estimators is compared and verified through simulations and experiments, which show that the two estimators are simple, have good robustness against parameter variation, and are accurate in parameter tracking. However, the estimator based on the Popov stability criterion, which can overcome parameter variation in a practical system, is superior in terms of response speed and convergence speed since there are both proportional and integral units in the estimator, in contrast to only one integral unit in the estimator based on the Lyapunov stability theorem. In addition, the estimator based on the Popov stability criterion does not need the expertise that is required in designing a Lyapunov function.