Fe-Mn-Si alloys are shape memory alloys which makeuse of the Y -E Stress-induced martensitic transformation.In this study, we report the effects of alloying additions on the shape memory effect (SME)of these alloys. It was found that the Mstemperature, the N6el temperature (TN) and the volume of stress-induced martensite govern the SME. Through the optimization of these factors we found that new alloy systems such as Fe-28Mn-6Si-5Cr. Fe-20Mn-5Si-8Cr-5Niand Fe-1 6Mn-5Si-12C~5Nialloys could exhibit good SME along with goodcorrosion resistance And it was also found that the thermomechanical treatment which improved the SME in Fe-Mn-Si base system was also effective to improve the SME of these new systems.KEYWORDS: Fe-Mn-Si alloy; shape memory ferrous alloy; shape memory effect: stress-induced Y -E martensitic transformation; Mstemperature: N6el temperature (TN): the amount of i• phase; training effect 1.

BackgroundThe Japanese Orthopaedic Association Hip Score is widely used in Japan, but this tool is designed to reflect the viewpoint of health-care providers rather than that of patients. In gauging the effect of medical therapies in addition to clinical results, it is necessary to assess quality of life (QOL) from the viewpoint of patients. However, there is no tool evaluating QOL for Japanese patients with hip-joint disease.MethodsWith the aim of more accurately classifying QOL for Japanese patients with hip-joint disease, we prepared a questionnaire with 58 items for the survey derived from 464 opinions obtained from approximately 100 Japanese patients with hip-joint disease and previously devised evaluation criteria. In the survey, we collected information on 501 cases, and 402 were subjected to factor analysis. From this, we formulated three categories—movement, mental, and pain—each comprising 7 items, for a total of 21 items to be used as evaluation criteria for hip-joint function.ResultsThe Cronbach’s α coefficients for the three categories were 0.93, 0.93, and 0.95, respectively, indicating the high reliability of the evaluation criteria. The 21 items included some related to the Asian lifestyle, such as use of a Japanese-style toilet and rising from the floor, which are not included in other evaluation tools.ConclusionsThis self-administered questionnaire may become a useful tool in the evaluation of not only Japanese patients, but also of members of other ethnic groups who engage in deep flexion of the hip joint during daily activities.

FeMnSi-based alloys exhibit a shape-memory effect associated with deformation-induced £ ¼ ¾ martensitic transformation and its reversion. The £ ¼ ¾ martensitic transformation also enhances mechanical properties, such as strength, hardness, wear-resistance and low-cycle fatigue lives of the alloys. In this article, we review fundamental researches on transformation behavior, microstructural and crystallographic characteristics, and functional and mechanical properties of the FeMnSi-based alloys, and introduce various examples of their practical applications. A special emphasis is placed on their new application as architectural seismic dampers, which were developed based on a new finding of the passive two-way martensitic transformations under cyclic tensile-compressive loading.

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BackgroundShelf acetabuloplasty has been applied to secondary osteoarthritis of the hip due to congenital dislocation or acetabular dysplasia; however, there are few reports on the long-term outcomes of this operation. Here, we aimed to investigate the long-term effects of our shelf acetabuloplasty for developmental dysplasia of the hip in adults.MethodsOutcomes for 28 hips (7 with pre-arthrosis, 21 with initial stage of arthrosis) were retrospectively reviewed clinically and radiologically at a minimum of 20 years after operation. Mean age of the patients at operation was 34 years (range 17–54 years), and the mean follow-up period was 25 years (range 20–32 years).ResultsMean Japanese Orthopaedic Association hip score improved from 76 points preoperatively to 82 points, and mean pain score improved from 24 points preoperatively to 33 points at 20 years. Mean Sharp angle improved from 51° preoperatively to 37° immediately after the operation. Similarly, the mean center-edge angle improved from −4° to 38°, and the mean acetabulum head index improved from 52 to 99%. More than 50% of the hips showed no change in joint space width at 20 years. Survival rates were 100% at 10 years, 93% at 20 years and 71% at 32 years, with conversion to total hip replacement as the endpoint.ConclusionLong-term outcomes of our shelf acetabuloplasty were comparable to other reports, and the clinical outcomes and survivorship revealed positive long-term effects of our procedure over approximately 20 years.

We investigate the ground-state phase diagram of the one-dimensional half-filled Hubbard model with an alternating potential-a model for the charge-transfer organic materials and the ferroelectric perovskites. We numerically determine the global phase diagram of this model using the level-crossing and the phenomenological renormalization-group methods based on the exact diagonalization calculations. Our results support the mechanism of the double phase transitions between Mott and a band insulators pointed out by Fabrizio, Gogolin, and Nersesyan [Phys. Rev. Lett. 83, 2014(1999]: We confirm the existence of the spontaneously dimerized phase as an intermediate state. Further we provide numerical evidences to check the criticalities on the phase boundaries. Especially, we perform the finite-size-scaling analysis of the excitation gap to show the two-dimensional Ising transition in the charge part. On the other hand, we confirm that the dimerized phase survives in the strong-coupling limit, which is one of the resultants of competition between the ionicity and correlation effects.

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