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Microstructure dependence on mechanical properties were investigated for Ti-17 forged at temperatures between 700 and 850 ˚C with deformation ratio from 33 to 80 %, and solutiontreated at 800˚C for 4 hours and aged at 620 ˚C for 8 hours. The microstructure was observed after solution and aging treatments. The volume fraction and the size of the primary alpha phase was controlled by solution treatment temperature, not forging temperature and deformation ratio. Forging temperature affected the morphology of grain boundary (GB) alpha phase. Deformation ratio affected the grain size and the aspect ratio of the horizontal and vertical grain size of the prior beta phase. The tensile strength was investigated at room temperature, 450, and 600 ˚C. Forging temperature and deformation ratio did not affect the tensile strength because there is no large difference of the volume fraction of the alphaphase. On the other hand, the elongation and the reduction of area increased with increase of the aspect ratio of the prior beta grains; that means, increase of the deformation ratio. Raising of forging temperature also increased elongation and reduction of area due to the film-like GB alphaphase.

The microstructures, tensile properties, and fatigue lives of the forged Ti-17 using a 1500-ton forging simulator subjected to different solution treatments and a common aging treatment under both load- and strain-controlled conditions to evaluate high cycle fatigue and low cycle fatigue lives, respectively were examined. Then, the tensile properties, microstructures, and relationships between fatigue lives and the microstructural factors were discussed. The fatigue limit under load-controlled conditions increases with increasing solution treatment temperature up to 1143 K, which is in the (α + β) region. However, it decreases with further increase in the solution treatment temperature to 1203 K in the b region. The fatigue ratio at fatigue limit is increasing with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase, and it relates well qualitatively with the volume fraction of the primary α phase when the solution treatment temperature is less than the b transus temperature. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life increases with decreasing solution treatment temperature, namely increasing the volume fraction of the primary α phase. The fatigue life under strain-controlled conditions to evaluate the low cycle fatigue life relates well quantitatively with the tensile true strain at breaking of the specimen and the volume fraction of the primary α phase for each total strain range.

Jinichi Hirano,1,2 Koichiro Watanabe,3 Takefumi Suzuki,1,4 Hiroyuki Uchida,1 Ryosuke Den,5 Taishiro Kishimoto,1 Takashi Nagasawa,5 Yusuke Tomita,4 Koichiro Hara,6 Hiromi Ochi,7 Yoshimi Kobayashi,1 Mutsuko Ishii,1 Akane Fujita,1 Yoshihiko Kanai,1 Megumi Goto,1 Hiromi Hayashi,1 Kanako Inamura,1 Fumiko Ooshima,1 Mariko Sumida,1 Tomoko Ozawa,1 Kayoko Sekigawa,1 Maki Nagaoka,1 Kae Yoshimura,1 Mika Konishi,1 Ataru Inagaki,1 Takuya Saito,8 Nobutaka Motohashi,9 Masaru Mimura,1 Yoshiro Okubo,8 Motoichiro Kato,11Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan; 2Ohizumi Hospital, Tokyo, Japan; 3Department of Psychiatry School of Medicine, Kyorin University, Tokyo, Japan; 4Inokashira Hospital, Tokyo, Japan; 5Komagino Hospital, Tokyo, Japan; 6Asai Hospital, Chiba, Japan; 7Kurumegaoka Hospital, Tokyo, Japan; 8Department of Psychiatry School of Medicine, Nippon Medical School, Tokyo, Japan; 9Department of Psychiatry, School of Medicine, University of Yamanashi, Yamanashi, JapanObjective: The use of an algorithm may facilitate measurement-based treatment and result in more rational therapy. We conducted a 1-year, open-label study to compare various outcomes of algorithm-based treatment (ALGO) for schizophrenia versus treatment-as-usual (TAU), for which evidence has been very scarce.Methods: In ALGO, patients with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) were treated with an algorithm consisting of a series of antipsychotic monotherapies that was guided by the total scores in the positive and negative syndrome scale (PANSS). When posttreatment PANSS total scores were above 70% of those at baseline in the first and second stages, or above 80% in the 3rd stage, patients proceeded to the next treatment stage with different antipsychotics. In contrast, TAU represented the best clinical judgment by treating psychiatrists.Results: Forty-two patients (21 females, 39.0 ± 10.9 years-old) participated in this study. The baseline PANSS total score indicated the presence of severe psychopathology and was significantly higher in the ALGO group (n = 25; 106.9 ± 20.0) than in the TAU group (n = 17; 92.2 ± 18.3) (P = 0.021). As a result of treatment, there were no significant differences in the PANSS reduction rates, premature attrition rates, as well as in a variety of other clinical measures between the groups. Despite an effort to make each group unique in pharmacologic treatment, it was found that pharmacotherapy in the TAU group eventually became similar in quality to that of the ALGO group.Conclusion: While the results need to be carefully interpreted in light of a hard-to-distinguish treatment manner between the two groups and more studies are necessary, algorithm-based antipsychotic treatments for schizophrenia compared well to treatment-as-usual in this study.Keywords: algorithm, open-label clinical trial, measurement-based treatment, schizophrenia, treatment-as-usual