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This study aims to develop a wheel profile optimization procedure to minimize flange wear considering the wear evolution. To this end, the wheel wear simulation capability is integrated into the profile optimization framework such that a total material loss can be minimized under design constraints. This allows for the wear reduction to be maintained over an extended traveling distance, while an optimized profile, minimizing the frictional energy for only the initial profile, would not ensure the optimum performance after the profile wear becomes significant. Furthermore, to enable a balanced mitigation of the profile wear and surface damage, the damage index model is introduced to the weighted objective function, considering profile wear evolution. Using flange wear tests with a scaled roller test rig, wear reduction of the optimized profile is experimentally validated. The wear simulation results agree with the test data. It is demonstrated that the flange wear and tread surface damages are reduced simultaneously over an extended traveling distance using the profile optimization procedure developed in this study.

The plasticity of high Si steels is improved remarkably by adding Cr in high purity steels. The factors which contribute to this phenomenon were investigated. At the normal level of purity, the plasticity of Fe –Si alloys is deteriorated by Cr addition. However, in high purity steels, the plasticity drastically improves when Cr is added. When the influence of microstructure was removed, the improvement of plasticity by adding Cr to high purity Fe –Si alloys was attributed to the suppression of deformation twinning formation. The microstructural improvement was explained by grain refinement and by formation of subgrains during hot rolling. The properties of these steels are expected to be applied to new functional steels.

Wear is a fundamental problem in the railroad vehicle design and performance evaluation. Slight changes in the profile shape result in significant impact on the contact geometry characteristics of wheel and rail, thereby altering the dynamic performance as well as derailment safety of railroad vehicles. In this study, a wear simulation capability integrated with multibody railroad vehicle dynamics simulation algorithms is developed considering multipoint contact exhibited between wheel and rail profiles in the wear evolution and validated against experimentally measured profiles obtained by the two-roller and scaled wheel wear tests. It was shown that worn profile shape as well as the magnitude of the weight loss agreed well between the simulation and test results in the two-roller test. Using wear test of a scaled wheel, it was found that the flange contact falls into severe wear regime, while the tread contact is in mild wear regime in the two-roller wear test data. However, a severe flange contact led to much higher wear rate than that obtained using the two-roller test for the same material and the same wear index, while the wear rate for the tread contact adhered to that of the two-roller test in the mild wear regime. This is attributed to the fact that contact condition of the severe flange contact scenario is greatly different from the two-roller contact condition due to the high contact pressure and slippage occurring in the small thin contact patch, leading to a vastly different wear rate per contact area. It is demonstrated that utilizing the flange wear rate leads to good agreement with the measured profile shape, while the two-roller wear rate leads to a significant underestimate of the flange wear due to significantly lower wear rate in severe wear regime.

Skeletal reconstruction of a child Neandertal unearthed at Dederiyeh Cave, Syria in 1993, is undertaken and the acquired stature discussed. Although the skeletal remains were well preserved, the reconstruction required several assumptions to be made because of the immature status of the specimen. The assumptions were mainly concerned with distances between bones in the inter-vertebral spaces and in the joints of the hip, knee, and ankle. These were estimated from X-ray films of modern children and data from previous studies. Stature was directly measured on the reconstruction, and found to be 79·2cm. After corrections for soft tissue thickness and shrinkage of the casts, the stature became 81·7cm. This estimate is consistent with estimates based on regression equations of long bone lengths, especially from those of the lower extremity. In comparison with longitudinal data for white American boys, the assessment of stature for Dederiyeh varied according to the estimated age. For a younger estimated age, the stature falls in the lower half of the white American range of variation, but with an older estimated age, it falls below the lower limit of the range of variation. Other immature Neandertals including two European specimens, Roc de Marsal and La Ferrassie 6, fall below the lower limit of the 5th to 95th percentile range based on the estimated statures from their long bone lengths. More comprehensive age assessment covering both fossil and modern humans is required before accurate conclusions in relation to Neandertal growth can be drawn.

Growth properties of carrot hairy root cells in various bioreactors were investigated. A turbine-blade reactor and an immobilized rotating drum reactor were found to be advantageous for the hairy root culture because of a high oxygen transfer coefficient (k in L a). After 30 days of culture, 10 g/l of dry hairy root cells were obtained in both bioreactors and maximum growth rates (Vm) were found to be 0.63 and 0.61 g/l per day for the turbine-blade reactor and immobilized rotating drum reactor, respectively. Specific growth rates (µ) at various cultivation times were observed to be linearly proportional to X/kla for both bioreactor configurations where X is the cell concentration. The estimated specific oxygen uptake rate of 0.34 mmol O2/g dry cells per hour compares fairly well with an experimental value of 0.3.

The thermal decomposition of methyl chloride diluted in Ar has been studied behind shock waves over the temperature range between 1680 and 2430 K and the total density range of 2.0×10−6–3.5×10−5mol cm−3. The decomposition rate was monitored by means of the UV absorption of the CH3radical produced. The initiation reaction was found to be the C–Cl bond fission; the process proceeded in the fall-off region under the present experimental conditions. From the fall-off data, low- and high-pressure rate constants (k0/[Ar] and k∞) were obtained by the application of a refined RRKM theory involving a weak collision effect. Thus, the Arrhenius expressions were given as:& k_0/[Ar]=10^15.56 exp(-247 kJ mol^-1/RT) cm^3 mol^-1 s^-1,& k_∞=10^13.86 exp(-383 kJ mol^-1/RT) s^-1.The collision efficiency factor, βc, was obtained as 0.02 at the mean temperature of the experiment by comparing the low-pressure rate constant with the strong collision-rate constant. The high-pressure rate constant was well explained by the maximum free-energy criterion presented by Quack and Troe.

The thermal gas-phase decomposition of vinyl bromide in Ar has been studied behind reflected shock waves over the temperature range between 1300 and 2000 K and the density range of 5.2×10−6–3.8×10−5mol cm−3by monitoring the UV absorption of C2H3Br and the IR emission of HBr. The decomposition proceeds viathe molecular elimination of HBr, and the unimolecular process is in the low-pressure region under the present experimental conditions. The low-pressure-limit rate constant was obtained ask2nd=1013.98±0.21exp{−(41.5±1.6 kcal mol−1)⁄RT} cm3mol−1s−1.The collision efficiency factor, βc, was obtained as about 2×10−4, considerably lower than that of vinyl chloride.

Thermal decomposition of isocyanic acid HNCO diluted to less than 2.0 mol% in argon was studied behind incident shock waves over the temperature range 2100–2500 K. The decomposition course was followed by monitoring the light absorption of HNCO and NH(3Σ−) at 206 and 336 nm, respectively. It is confirmed that the primary step of the decomposition is a bimolecular process HNCO+Ar→NH(3Σ−)+CO+Ar, ΔH°0=337 kJ mol−1, with the low-pressure limit rate constants k=1017.23±0.36exp[−(402±17) kJ mol−1/RT] cm3mol−1s−1. The siglet-to-triplet crossing point is estimated on the basis of the RRKM low-pressure-limit rate constant calculations. The overall decomposition mechanism is suggested and its validity is confirmed by computer simulation of the time–concentration profiles of NH(3Σ−) at varying temperature.

Pathways for the thermal unimolecular reactions of the CH2CH2NH diradicals, both singlet and triplet, have been investigated by ab initio MO calculations using 4-31G basis functions. The minimum-energy paths for possible isomerizations and fragmentations are traced by the SCF gradient procedure, and multireference double-excitation (MRD) CI calculations carried out for all the stationary structures located. The results of calculation show that the energetically most favorable unimolecular reaction possible to the triplet diradical is an α-hydrogen detachment giving rise to CH2=CH–NH (2A″), whereas that to the singlet diradical is a 1,2-hydrogen migration to give CH3CH=NH (1A′). The activation barrier heights calculated for the two processes are 103 and 74 kJ mol−1, respectively. It is concluded that, in the gas phase, CH3CN and HCN should be formed concurrently by the α-bond cleavages of the doublet radical CH3CH=N (2A′), which will arise most readily from the vibrationally hot CH3CH=NH (1A′).

The thermal gas-phase decomposition of methyl iodide diluted in Ar has been studied behind shock waves over the temperature range between 1050 and 1500 K and the total density range of 3.5×10-6–3.9×10-5mol cm-3. The decomposition was monitored by means of the UV absorption of CH3I at 259 or 275 nm. The initiation reaction was found to be the C–I bond fission, and the process proceeded in the low-pressure region under the present experimental conditions. The low-pressure limit rate constant was obtained as:k_2nd=10^15.40±0.26exp{-(42.56±1.50 kcal mol^-1)/RT}cm^3 mol^-1s^-1.Applying the RRKM strong collision theory, the collision efficiency factor was estimated to be 0.018 at 1300 K.

No relevant conflicts of interest to declare.

[Background] We have been performing reduced-intensity stem cell transplantation (RIST) to avoid preconditioning-related complications. However, the effectiveness of RIST in pediatric patients with acute lymphoblastic leukemia (ALL) remains to be clarified.

Previous studies showed an association between iron overload and hematopoietic transplant complications. Serum ferritin is widely used as an indicator for iron stores and an elevated pretransplantation level was strongly associated with inferior outcomes of transplantation in adults, though it has not been clarified well in pediatric patients. We studied prognostic impact of pretransplantation elevated ferritin levels on outcomes of allo-HSCT for pediatric hematological diseases.We studied 93 consecutive pediatric patients (< 18 years old) with hematologic disease who underwent allogeneic HSCT at Osaka Medical Center and Research Institute for Maternal and Child Health between 2003 and 2009 in whom pretransplantation serum ferritin levels were available. The patients were divided into two groups, pretransplantation serum ferritin level = 1000 ng/mL (SF=1000) and ferritin level < 1000 ng/mL (SF<1000). Survival rate was estimated using the Kaplan-Meier method and compared between the two groups using the log-rank test. The association of pretransplantation ferritin and the transplant outcomes was evaluated in multivariate analysis with Cox proportional-hazards regression model.At 5 years after transplant, children in SF=1000 (n=51) had a significantly lower overall survival (OS; 42.1% vs 76.6, p=0.001) and a higher non-relapse mortality (NRM; 41.0% vs 18.6%, p=0.018) than those in SF<1000 (n=42). SF=1000 (n=20) in patients with leukemia in nonCR had lower OS (14.4% vs 75.0%, p=0.051) than SF<1000 (n=5), whereas patients in CR had almost the same OS (65.8% vs 62.2%, p=0.920) between SF=1000 (n=14) and SF<1000 (n=14), although the sample size was too small to detect statistically significant difference. Univariate analyses revealed elevated ferritin level, leukemia, nonCR, GVHD grade 3-4 and haploidentical donor as significant worse prognostic factors for OS and cord blood transplant as a significant better factor. In multivariate analysis, an elevated pretransplantation serum ferritin level was the only significant prognostic factor for worse overall survival [HR(95%CI): 2.35 (1.05-5.27), p=0.038]. There was no significant difference in the incience of acute GVHD, infection and any other complications as causes of nonrelapse death between the two groups, although the total incidence of fatal transplant-related complications was significant higher in SF=1000.Our results indicate that an elevated pretransplant serum ferritin level adversely affects outcomes of allogeneic transplantation in pediatric patients as reported in adults. The adverse impact of elevated ferritin levels on survival resulted from increased NRM. The association between high ferritin levels, which are usually caused by iron overload, and outcomes of transplantation in pediatric patients requires further prospective studies.No relevant conflicts of interest to declare.

Previous studies showed an association between iron overload and hematopoietic transplant complications. Serum ferritin is widely used as an indicator for iron stores and an elevated pretransplantation level was strongly associated with inferior outcomes of transplantation in adults, though it has not been clarified well in pediatric patients. We studied prognostic impact of pretransplantation elevated ferritin levels on outcomes of allo-HSCT for pediatric hematological diseases.

Recently, HSCT has been widely used as a curative therapy for refractory hematological/malignant diseases. However, late complications after HSCT such as endocrine disorders, infertility, short stature and secondary cancers have been recognized as serious problems in children. Late complications are assumed to be much more serious in younger children, especially in infants. Therefore, we retrospectively evaluated late complications among patients who underwent HSCT before one-year-old age in our institute to clarify this big issue.We performed HSCT in 530 children from 1993 to 2009. Among these 530 patients, 33 were infants (younger than 1- year - old) at HSCT. 23 infants with malignant disorders consisted of neuroblastoma 10, hepatoblastoma 2, rhabdomyosarcoma 1, retinoblastoma 1, acute lymphoblastic leukemia 5, myelodysplastic syndrome 2, acute myelogenous leukemia 2, and 10 infants with non-malignant disorders consisted of immunodeficiency 5, familial hemophagocytic lymphohistiocytosis/hemophagocytic syndrome 2, congenital metabolic disorder 1, severe aplastic anemia 1, pure red cell aplasia 1 were included. 9 infants underwent autologous HSCT and 24 underwent allogeneic HSCT. 22 infants received MAC and 11 received reduced-intensity conditioning (RIC). 26 out of 33 patients have been alive (MAC, 18/22 = 81.8 %; RIC, 8/11 = 72.7 %). Body height (BH) of 5 patients in RIC group who have been surviving longer than 5 years after HSCT is equal or taller than -2 standard deviation (SD) of BH. However, BH of 6 out of 13 evaluable patients in MAC group remains shorter than -2 SD (the shortest, -5.3 SD) of BH. All survivors in MAC group are suffering from one or more late complications such as growth hormone secretion insufficiency, premature puberty, hypothyroidism, gonadal failure and secondary cancers, therefore, they needs treatment and support for these late complications.The survival rate is similar (81.8 % versus 72.7 %) between MAC and RIC in infants, however, infants who underwent MAC-HSCT are suffering from late complications much more frequently and need treatment and support. These results suggest that less toxic conditioning should be adopted for infants who undergo HSCT to avoid serious late complications.No relevant conflicts of interest to declare.

RIC has been applied mainly for elderly patients and patients with comorbidity to expand opportunity for such adult patients to undergo HSCT. The burden of late effects after HSCT followed by myeloablative conditioning is not negligible in pediatric patients. RIC should be introduced to avoid not only treatment related morbidity (TRM) but also late effects for children even if they are not ineligible for myeloablative transplantation. However, enhanced graft-versus-leukemia (GVL) effect by choosing an alternative donor in the setting of RIC-HSCT for pediatric ALL hasn't been clarified, so far.We retrospectively analyzed 22 children with ALL who underwent RIC followed by HSCT from an alternative donor between 2001 and 2008 in our institute.The median age of 22 patients at HSCT was 9 years (range one year - 19 years). 8 patients in CR1, two in CR2 and 12 beyond CR2 underwent HSCT from an alternative donor followed by Flu 180mg/m2 and LPAM 140 mg/m2 containing RIC. 8 patients who relapsed after myeloablative HSCT and 5 patients with Ph1-ALL were included. Unrelated bone marrow (BM) in 7 patients and unrelated cord blood in 4 were transplanted. 11 patients were transplanted from a haplo-identical parent (8, BM; 3, selected CD34 positive peripheral blood mononuclear cells). Engraftment was confirmed in 21 transplants out of 22 (95.4%). Death of TRM within 100 days after transplant was observed in 3/22 (13.6%). Acute graft-versus-host disease (GVHD) grade IV wasn't observed. Acute GVHD grade II and III occurred in 8/21 (38.1%) and 6/21 (28.6%), respectively. Chronic GVHD was seen in 8/16 (50%). 14 patients (63.6%) out of 22 are surviving after RIC-HSCT for median 36 months (range, 24 – 100 months). 9 patients (90%) out of 10 in CR1/CR2 and 5 (41.7%) out of 12 beyond CR2 are surviving.These results suggest RIC-HSCT from an alternative donor for pediatric ALL can be performed safely and similar outcome can be expected compared to myeloablative transplantation.No relevant conflicts of interest to declare.

Abstract 4572

Abstract 4501

A new method of fabricating silica glass optical waveguides has been developed. Porous silica glasses made by the sol-gel method were used as substrates, into which a dopant was introduced by utilizing the adsorption equilibrium between porous glass and vapor of the relevant dopant material. Index distributions within the glass were produced by placing the doped glass under reduced pressure to outgas the dopant from the surface of the glass, followed by transforming the dopant into oxide by hydrolysis, and then the porous glass was densified to give nonporous glass. Combining this method with the selective photopolymerization method, where the undesired portion of pores was clogged by polymer, 3D waveguides have been fabricated. The SiO2-GeO2waveguides thus fabricated have index differences of more than 0.02 with the propagation loss of less than 1 dB/cm.