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An Fe–1 at.% Cu model alloy was examined by atom probe (3DAP) and small-angle neutron scattering (SANS) to verify the accordance of the gained results. The Fe-Cu alloy was heat-treated for various times at 500°C, forming Cu-rich precipitates within the Fe matrix. The chemical compositions of the precipitates and matrix found by 3DAP were used to calculate the magnetic scattering contrast. Additionally, a magnetic moment of the precipitates that contain a significant amount of Fe was taken into account for the calculation of magnetic scattering contrast. This in turn is used for the evaluation of the magnetic scattering curves gained by SANS. Both the 3DAP data as well as the scattering curves were analyzed with regard to radius, number density, and volume fraction of the precipitates as a function of aging time. The results yielded by both techniques are in good agreement and correspond to the development of the hardness of the alloy. Minor differences can be related to the cluster search algorithm used for the analysis of the 3DAP data as well as Fe overestimation based on different field phases. [ABSTRACT FROM AUTHOR]

The article presents a study on the Corrax maraging steel's microstructures and mechanical properties. It also discusses the process of precipitation hardening, along with ageing in metals. It states that the amount of reverted austenite found in the maraging steel is about 1-2 vol.%, and the delay of reverted austenite formation during ageing is caused by the absence of titanium (Ti) in the steel.

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Abstract: The microstructural evolution of an experimental Fe-1.4C-2.6Cr-1.4Mo-6.0Ni-5.0Al (composition in at.%) secondary hardening steel has been studied during isothermal aging at 610°C. Atom probe field ion microscopy and transmission electron microscopy have been used to characterise precipitate types and precipitation sequences as well as to examine changes in the solute distribution. The strengthening effects were identified as multiphase precipitation processes of secondary hardening carbides and an intermetallic β-NiAl phase, starting at aging times of less than 1min. The results are discussed regarding the evolution of phase composition and precipitate morphology. Special emphasis is placed on the comparison of the NiAl precipitation behaviour in the investigated experimental steel and in C-free PH13-8 maraging steel. [Copyright &y& Elsevier]

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Small-angle neutron scattering (SANS) and energy-filtered transmission electron microscopy (EFTEM) were employed to characterise the precipitation behaviour in the high-speed steel HS6-5-2 during tempering. With SANS the evolution of the size distribution of precipitates during isothermal tempering at 590°C was investigated. The SANS results are discussed assuming that three populations of precipitates can be distinguished during tempering at 590°C. The smallest population with sizes around 1nm is supposed to be carbon-rich clusters. Intermediate-sized particles between approximately 1 and 10nm might be either MC and/or M2C carbides, which cannot be distinguished by SANS. In addition, the ratio A of magnetic and nuclear scattering intensity was used to gain information on the composition of the precipitates. The A-ratio is discussed assuming a substitution of iron in the precipitates by carbide forming elements with increasing tempering time. Finally, the correlation of the results obtained by SANS with those achieved by EFTEM is presented. [Copyright &y& Elsevier]

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BHM Berg- und Hüttenmännische Monatshefte is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Complex structure examinations were performed on high-speed steels of different grades obtained using conventional metallurgy and produced by application of powder metallurgy. Hot hardness measurements were focused on the secondary carbide precipitation. Transmission electron microscopy and X-ray diffraction studies established the type of primary carbides and the amount of retained austenite. Scanning electron microscopy examinations were used to calculate the volume fraction of primary carbides. The contribution of the applied heat treatment and laser modification by diode laser remelting to the residual stress state was studied. Energy filtering was used to study the secondary carbides of nanometer size. [Copyright &y& Elsevier]

A network discourse has emerged during the last two decades, representing networks as self–organizing, collaborative, nonhierarchical, flexible, and topological. Progressive scholars initially embraced networks as an alternative to markets and hierarchies; neoliberal thinkers and policymakers have reinterpreted them in order to serve a neoliberal agenda of enhanced economic competitiveness, a leaner and more efficient state, and a more flexible governance. The European Commission and the German state have initiated and financially supported interurban network programs, broadly framed within this neoliberal network discourse, despite their long traditions of regulated capitalism. Really existing interurban networks depart, however, from these discourses. Embedded within pre–existing processes of uneven development and hierarchical state structures, and exhibiting internal power hierarchies, really existing networks are created, regulated, and evaluated by state institutions, and often exclude institutions and members of civil society, making them effective channels for disseminating a neoliberal agenda. At the same time, they create new political spaces for cities to challenge existing state structures and relations and are of unequal potential benefit to participating cities, both of which may catalyze resistance to neoliberalization. [ABSTRACT FROM AUTHOR]

In order to determine whether principles of environmental justice have been violated, a large number of empirical studies have been carried out to ascertain whether minority and low-income populations are disproportionately exposed to industrial pollution. This study provides a comparative evaluation of two commonly employed proximity measures in GIS-based environmental equity assessment, examining their influence on the results of the analysis, and proposes a methodology for evaluating the significance of these results. 1990 census data on population characteristics and data from the 1995 EPA's toxic release inventory (TRI) for the City of Minneapolis, MN are used. These results also allow a preliminary assessment of environmental equity/inequity in potential exposure to airborne toxic chemicals for racial minorities, poor people and children in Minneapolis. In the third part of the paper we develop and employ a geographic randomization methodology for assessing the significance of these results. [ABSTRACT FROM AUTHOR]

Argues that more attention should be paid to the role of supply side factors in accounting for the spatiotemporal evolution of urban office building cycles, particularly during the 1980s boom. Comparative analysis of cycles between 1963 to 1986 in the United States; Convergence in timing; Analysis of interurban differences.

Between October 1989 and Junuary 1991 five children with brain stem tumors were treated with sequential chemo- and radiotherapy. The polychemotherapy consisted of procarbazine, ifosfamide, etoposide, methotrexate, cisplatin and cytosine arabinoside. Locally, hyperfractionated radiotherapy was delivered at a total dose of 63.8 Gy (1.1 Gy twice daily, 10 fractions per week). After a median observation time of 11.8 (range 4-23) months from diagnosis three children are alive and without evidence of tumor progression. Two patients died from tumor progression 11 and 16 months respectively after initiation of therapy. [ABSTRACT FROM AUTHOR]

Because cancer of the male breast is rare knowledge about its biology and behavior is essentially due to a compilation of pooled experiences. Hence, a continued report of cases appears to be important. Therefore a retrospective review of patients suffering from male breast cancer was carried out. Twenty-four evaluable cases were analyzed. Eight patients (1 patient with bilateral Stage I carcinoma was included) were in Stage I, 7 in Stage II, 2 in Stage IIIa, 4 in Stage IIIb, and 3 in Stage IV. Of 23 patients who were treated with mastectomy, 22 had modified radical mastectomy and postoperative irradiation to the chest wall as well as to the peripheral lymphatic areas in most cases. One patient underwent radical mastectomy. Another patient had an excision biopsy only, followed by irradiation. One of 24 patients received tamoxifen; another received cyclophosphamide, methotrexate, 5-fluorouracil, predisone (CMF) regimen in an adjuvant setting. Local recurrence developed in one of 23 (4%) patients treated with mastectomy and radiation therapy to the chest wall and peripheral lymphatics. Four (17%) patients developed distant metastases. The 5-year overall survival (Kaplan-Maier) was 90% for the entire group, 100% for patients in Stage I-III disease, and 60% in Stage IV disease ( P = <0.005). As observed in former reports the stage of disease at initial presentation seems to be a parameter that significantly contributes to survival in male breast cancer patients. To what extent improved local control by adequate local therapy, such as surgery and postoperative radiotherapy, may improve overall survival remains to be discussed. [ABSTRACT FROM AUTHOR]

The kinetic characteristics of galactose-1-phosphate uridyltransferase and galactokinase in cultivated fibroblasts and amniotic fluid cells were investigated. The K values of galactokinase for galactose at 2.0 m M ATP are 0.34 m M in amniotic fluid cells and 0.48 m M in fibroblasts. The K values for ATP at 0.5 m M galactose are 1.25 m M and 2.10 m M. Transferase and galactokinase activities and protein content increase logarithmically during the growth of cultivated cells. The specific activity of both enzymes also increases and reaches a maximum level 10-15 days after subculture. The specific activity of transferase increases faster than that of galactokinase in the case of amniotic fluid cells. In the case of fibroblasts the specific activity of galactokinase increases faster than that of transferase. [ABSTRACT FROM AUTHOR]

The function of Con A stimulation was investigated in patients with ALL in remission and in patients with ALL in the acute phase of the disease as compared to healthy controls. Suppression of the Con A response brought about by autologous Con A-activated cells was significantly lower in ALL patients in remission (mean value 29.33%) and in the acute phase (mean value 10%) than in the controls (mean value 64.86%). Suppression of the Con A stimulation of control lymphocytes by Con A-activated homologous cells of ALL patients had a mean value of 51.65%. This was significantly higher than the suppression obtained by the same ALL cells in the autologous system and of the same order of magnitude as the suppression obtained by control ConA-activated cells on control Con A stimulation (57.67%). Suppression of the Con A response of ALL lymphocytes produced by control Con A-activated cells was 23.17% and comparable to healthy controls. These results demonstrate that the function of Con A-induced suppression is significantly lower in ALL patients. The further indicate that at least two cell types are involved in this kind of suppression in humans. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Neurology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)