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171.
V. N. Ponomareva T. M. Kuzina A. M. Levin V. S. Yakovleva I. S. Lavrov 《Refractories and Industrial Ceramics》1985,26(5-6):309-311
Conclusions The coagulating action of aluminum sulfate and of the combination of it with polyacrylamide on a suspension of chamotte and clay, leading to a significant increase in particle size of the dispersed phase, was investigated.The presence of a threshold value of the addition of coagulant as an important production parameter determining the unstable suspension type sedimentation of particles was shown.To disturb the stability of the systems and to accelerate the clarification process of waste waters contaminated with chamotte and clay the necessary additions of reagents are 25–50 mg/liter of aluminum sulfate and 5 mg/liter of polyacrylamide.Translated from Ogneupory, No. 6, pp. 42–44, June, 1985. 相似文献
172.
Breast conservation and prolonged chemotherapy for locally advanced breast cancer: the University of Michigan experience 总被引:1,自引:0,他引:1
SD Merajver BL Weber R Cody D Zhang M Strawderman KA Calzone V LeClaire A Levin J Irani M Halvie D August M Wicha A Lichter LJ Pierce 《Canadian Metallurgical Quarterly》1997,15(8):2873-2881
PURPOSE: To determine whether breast conservation and prolonged neoadjuvant chemotherapy have efficacy in locally advanced breast cancer (LABC), as measured by survival and rate of breast conservation. MATERIALS AND METHODS: Eighty-nine patients with stage III disease were enrolled at the University of Michigan (UM) onto a prospective nonrandomized trial. Patients received nine 21-day cycles of neoadjuvant chemohormonal therapy that consisted of doxorubicin 30 mg/m2 and cyclophosphamide 750 mg/m2 intravenously on day 1, conjugated estrogens 0.625 mg orally twice daily on days 6 to 8, methotrexate 40 mg/m2 and fluorouracil 500 mg/m2 intravenously on day 8, and tamoxifen 10 mg orally twice daily on days 9 to 14. Patients with a negative biopsy received radiation only, while those with residual disease underwent mastectomy and postoperative radiotherapy. Eight more cycles of chemohormonal therapy were administered after local-regional therapy. RESULTS: The clinical response rate to neoadjuvant therapy was 97%, 28% of patients had a complete pathologic response evaluated at biopsy. Five-year overall and disease-free survival probabilities were 54% and 44%, respectively. The median disease-free survival time was 2.4 years. The 5-year actuarial rates of local-regional control with local failure as only first failure were 82% and 78% following radiotherapy, and mastectomy and radiotherapy, respectively (P = .99). CONCLUSION: Prolonged neoadjuvant chemohormonal therapy and biopsy-driven local therapy have efficacy in LABC, with 28% of patients being candidates for breast conservation and a 5-year overall survival rate of 54%. 相似文献
173.
A. A. Levin D. C. Meyer A. Gorbunov A. Mensch W. Pompe P. Paufler 《Journal of Alloys and Compounds》2003,360(1-2):107-117
Metastable Fe–Cr alloy films of various composition prepared by cross-beam pulsed laser deposition using two different procedures are investigated by wide-angle X-ray scattering. Depending on the Fe–Cr composition of the samples in an extended range, a body-centered cubic (bcc) phase or metastable phases with body-centered tetragonal (bct), face-centered orthorhombic (fco) or primitive orthorhombic (po) and primitive cubic (pc) lattices are formed in the films prepared by simultaneous co-deposition of Fe and Cr. In the films produced by layer-by-layer deposition of thin separate Fe and Cr layers (thickness of about 1 nm), only bcc and bct Fe–Cr phases were observed. A long-time annealing (50 h) at a temperature of 425 °C near the low-temperature existence limit of the σ-phase under equilibrium conditions followed by slow cooling (rate 0.5 °C/min) has been performed and various phase transformations were observed. In addition to known equilibrium and metastable Fe–Cr crystalline phases (mainly bcc and bct phases in the films prepared by layer-by-layer technique and bcc, bct and σ-FeCr phases in co-deposited films), a new metastable Fe–Cr superstructure characterised by a primitive tetragonal lattice with parameters a and c of about 0.57 and 0.63 nm, respectively, has been identified. It is shown that the formation of ″-crystallites with preferred orientation in the metastable Fe–Cr alloy films during dedicated long-time annealing gives rise to a spatially periodic modulation of chemical composition resulting in the formation of multilayers with periods of one or a few atomic monolayers of individual Fe and Cr components. 相似文献
174.
A new tachometric chamber flowmeter of the roller-vane type has been developed. The flowmeter has a working volume of 500 cm3/rev. Results of tests of the instrument are reported.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 30–34, August, 1995. 相似文献
175.
Evaluated the relation between self-reported frequency of nightmares, a number of saliency measures of the nightmare experience, and a self-report measure of annihilation anxiety (appended) for 1,357 undergraduates from 2 independent populations. A significant positive relation was found between nightmare frequency and salience and annihilation anxiety. Findings were cross-validated across both samples. Results are discussed within the context of object relations and ego psychology theory utilizing an ego boundary model and are consistent with previous research (e.g., E. Hartmann, 1991) demonstrating boundary impairment in Ss with self-reported frequent nightmares. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
176.
Salvage of lower-extremity Gustilo type IIIC fractures is difficult, time-consuming for the patients and physicians, and not universally successful because of poor functional outcomes. Even if successful with limb salvage, the functional result may be unsatisfactory because of mutilating injuries to muscle and nerve, bone loss, and the presence of chronic infection. From July 1991 until July 1994, revascularizations of open IIIC fractures were attempted for wounds with Mangled Extremity Severity Score (MESS) < or = 10. The functional results were evaluated at 2 years after injury. Thirty-six lower-extremity revascularizations were performed on 34 patients, including 1 patient with bilateral distal tibial IIIC fractures and a child with IIIC femoral fracture accompanied by ipsilateral distal tibial amputation. Excluded were patients with below-ankle IIIC fractures as well as patients who underwent immediate amputation at admission. After the revascularization, seven patients with IIIC fractures (7 of 36, 19.4%) underwent secondary amputation within 1 week. At the 2-year follow-up, the overall secondary amputation rate was 25% (9 of 36) and the salvage rate was 75% (27 of 36). Those were no deaths. Of the 29 salvaged limbs among these 27 patients, 23 limbs (23 of 29, 79.3%) required secondary coverage procedures that included 12 free flap transfers (12 of 29, 41.4%). Every patient needed subsequent reconstructive surgery to achieve an acceptable functional result. In this series, MESS was able to predict the secondary amputation rate and the functional result. Sixteen of the 17 limb-salvaged patients with MESS < or = 7 were able to achieve minimal functional requirements, whereas 3 of the 10 patients with MESS = 8 to 10 failed to achieve minimal functional requirements at the 2-year follow-up. Using statistical analysis, we found that the salvaged limbs with MESS < or = 9 exhibited a significant difference in achieving adequate function compared with limbs with MESS > 9. Using our protocol for treatment for IIIC fractures, the threshold for immediate amputation can be raised from MESS = 7 to MESS = 9. Our conclusions are (1) more severely injured limbs have poor functional results, (2) every patient needs subsequent reconstructive surgery, and (3) the MESS may be helpful in decision-making. 相似文献
177.
Perceptual priming of proper names in young and older normal adults and a patient with prosopanomia.
The purpose of this study was to determine if normal participants and a patient with prosopanomia can be perceptually primed for proper names. To this end, 2 experiments were conducted. In Experiment 1, normative data were collected on 4 proper-name priming tasks. The variables of levels of processing at encoding and age were manipulated. Robust priming results were obtained that were not influenced by either of these variables. The results of Experiment 2 indicated that prosopanomic patient, N.G., demonstrated normal repetition priming, despite her marked impairment in deliberate retrieval of person and city names. These results are interpreted in terms of a dissociation between explicit and implicit memory for proper names and suggest that the deficit in prosopanomia only involves deliberate access to the name; access to presemantic representations of the visual word form remains intact. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
178.
179.
Iris Levin 《住房,理论和社会》2014,31(1):54-75
The meaning of migrant housing materiality has not been adequately researched, especially when compared to the meaning of the home for immigrants, a matter of extensive discussion in the past two decades. This paper focuses on the meaning of housing materiality for 12 immigrants who migrated from Morocco to Israel some 60?years ago. Drawing on qualitative data gathered in 2007 and 2008, the paper develops a theoretical framework considering “house as community” and “house materiality” as two interrelating explanations for the migrant housing materiality. Through this framework, and with the concepts of performance and performativity, the paper first explores former houses of participants in Morocco and then presents current houses in Tel Aviv, Israel, to establish links between the two housing forms and reveal the meanings of objects in the homes. It is argued that as a reaction to the dominant Israeli society, housing materiality enables participants to educate successive generations and Israeli society at large about the rich cultural life of Moroccan-Jews that existed before their migration to Israel. 相似文献
180.
We present a comprehensive robot development process and its evaluation. We designed this process in the context of a robotics course in high schools. The motivation for designing this new process was improving the robustness and reliability of robots developed by students and preparing students for becoming better designers. The newly designed process proved to be highly successful in designing top quality robots. In the process design, we explored and adapted existing design tools and methods to the specific designers, the nature of the product, the environment, the product needs, and the design context goals. At the end of this thorough design, we selected a synergetic integration of six tools and methods to compose the new comprehensive development process for this product context: conceptual design, fault-tolerant design, atomic requirements, fuzzy logic for control, creative thinking, and microprogramming-based design. The design skills of the students that learned the design process and the performance of robots they designed and participated in an international robotics contest were examined. The high school teams that studied the proposed process won the first places in an international contest. The robots developed by the students had better performance than robots built by engineers and faculty teams. Professional experts rated the robots’ designs as excellent. The students that studied the process demonstrated high level of diverse design skills including creativity and design management capabilities. Additionally, they improved their science subject grades and their attitude toward engineering. Both the results obtained by the study and the authors’ experience in teaching robotics demonstrate that the proposed robot development process could be taught successfully in high school and that it leads to superior robotic products. Our experience also indicates that this process could serve industry design by improving the robustness of robots operating in uncertain environments and supporting fast change management practices. 相似文献