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81.
Delphine Antoni Jean-Baptiste Clavier Marius Pop Catherine Schumacher Fran?ois Lefebvre Georges No?l 《International journal of molecular sciences》2014,15(5):7554-7562
Purpose
to evaluate the role of whole brain radiotherapy (WBRT) and radiation boost (RB) for 208 patients recursive partitioning analysis (RPA) II with 1 or 2 brain metastases (BM) at a single institution.Methods and Materials
the dose of WBRT was 30 Gy (10 fractions of 3 Gy). One hundred thirty-two patients (63.5%) benefited from RB of 9 Gy in 3 fractions of 3 Gy at the metastatic site. Patients had 1 or 2 BM in 122 (58.7%) and 86 cases (41.3%), respectively.Results
patients with one or two metastases had similar survival (4.6 and 5.1 months, respectively) (p = 0.4). Median overall survival (OS) for patients treated with WBRT and RB, and with WBRT alone was 5.9 and 3.7 months, respectively (p = 0.03). The 6-, 12- and 24-month OS rates after WBRT and RB were 48.5%, 25% and 10.6%, respectively, while WBRT alone resulted in OS rates of 34%, 22.4% and 3.2%, respectively (p = 0.03). After WBRT and RB, the 6-, 12- and 24-month local control rates were 92%, 82% and 67%, respectively, while they were 81.2%, 75% and 37.5%, respectively, after WBRT alone (p = 0.03). The 6-, 12- and 24-month brain control rates after WBRT and RB were 88.7%, 75.8% and 62%, respectively, and after WBRT alone they were 78.5%, 59% and 37.7%, respectively (p = 0.03).Conclusion
additional boost delivered with 3D conformal radiotherapy improves local and brain control rates significantly as well as overall survival for RPA II patients with 1 or 2 unresectable BM. 相似文献82.
Impact of Blend Morphology on Interface State Recombination in Bulk Heterojunction Organic Solar Cells
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Benjamin Bouthinon Raphaël Clerc Jérôme Vaillant Jean‐Marie Verilhac Jérôme Faure‐Vincent David Djurado Irina Ionica Gabriel Man Antoine Gras Georges Pananakakis Romain Gwoziecki Antoine Kahn 《Advanced functional materials》2015,25(7):1090-1101
This work is a reinvestigation of the impact of blend morphology and thermal annealing on the electrical performance of regioregular‐P3HT:PC60BM bulk heterojunction organic solar cells. The morphological, structural, and electrical properties of the blend are experimentally investigated with atomic force microscopy, X‐ray diffraction, and time‐of‐flight measurements. Current–voltage characteristics of photodiode devices are measured in the dark and under illumination. Finally, the existence of exponential electronic band tails due to gap states is experimentally confirmed by measuring the device spectral response in the subband gap regime. This method reveals the existence of a large density of gap states, which is partially and systematically reduced by thermal annealing. When the band tails are properly accounted for in the drift and diffusion simulations, experimentally measured charge transport characteristics, under both dark and illuminated conditions and as a function of annealing time, can be satisfactorily reproduced. This work further confirms the critical impact of tails states on the performance of solar cells. 相似文献
83.
The stability of hydrogen in ZnO is studied using hydrogenated nanowires by plasma treatment. Enhanced near band edge UV emission and reduced defect level green emission is observed after hydrogen plasma treatment. Through thermal stability tests, this effect is found to be stable at room temperature and nearly stable up to ~500 K, but begins to deteriorate at higher temperature. The study of the irradiation stability of the hydrogen in ZnO nanowires shows that the hydrogen is stable under an electron beam with an accelerating voltage lower than 5 kV, but is not stable under 10 kV or under an intensive laser beam. The results could benefit the further understanding of the role of hydrogen in ZnO and light-emitting devices based on hydrogenated ZnO. 相似文献
84.
Bogdan C. Gagea Andrei N. Pârvulescu Georges Poncelet Vasile I. Pârvulescu 《Catalysis Letters》2005,102(3-4):219-222
Friedel-Crafts alkylations of α-methylnaphthalene with various alkylating agents were first carried out in the presence of methanesulfonic acid (MeSA). The Brønsted acid catalyst MeSA exhibited outstanding catalytic performance, and was found to be excellent catalyst and solvent for alkylation reaction of aromatic hydrocarbon. It’s found that alkenes can be used as excellent alkylating agent for alkylation of α-methylnaphthalene. The effects of various reaction parameters like type of alkylating agent, dosages of catalysts, reaction temperature and reaction time were investigated in detail. Moreover, the performance of reuse for catalysts was also studied. It’s found that, under the optimal reaction conditions, more than 90% of conversion for olefins and 100% of selectivity for the desired products were obtained. Compared with traditional catalysis technology, the reaction, catalyzed by MeSA catalyst, no volatile solvents needed, good selectivity for desired products could be obtained. The catalyst can be isolated easily from the reaction mixtures by decantation, and was successfully reused. The methanesulfonic acid could be considered as environmentally friendly novel catalyst and solvent for long-chain alkylation of α-methylnaphthalene with alkenes. The catalytic reaction mechanism for alkylation in the presence of MeSA was proposed as well. 相似文献
85.
M Vaillant P Millet A Luty P Tshopamba F Lekoulou J Mayombo AJ Georges P Deloron 《Canadian Metallurgical Quarterly》1997,2(9):917-919
The efficacy of a 3-day clindamycin-quinine regimen to treat clinical malaria attacks was investigated in 256 children from western Gabon. Treatment was well tolerated by all of the children and its efficacy was higher than 97% by day 20. Thus this 3-day clindamycin-quinine regimen might constitute a potential alternative to chloroquine for treating clinical malarial attacks in children from Gabon. 相似文献
86.
87.
Issues related to the automated identification and elimination of the adverse influence of small geometric model features on the quality of automatically generated meshes, using local mesh modification operators, are addressed. The definition of mesh validity with respect to the geometric model is extended to include multiple mesh entity classifications. Checks based on mesh topology are used to ensure no dimensional reductions in the locally modified mesh. Example geometric models of varied complexity containing small geometric features are used to demonstrate the ability of presented procedures to improve mesh quality in terms of aspect ratio and small angle metrics. 相似文献
88.
Thomas Antretter Franz Dieter Fischer Kikuaki Tanaka Georges Cailletaud 《国际钢铁研究》2002,73(6-7):225-235
This paper presents an overview of the co‐operative efforts aiming at the correct characterisation of the thermo‐mechanical behaviour of materials during the process of a phase change. In the first section the physical conditions for the onset of transformation processes, either diffusive or massive or displacive, expressed in terms of the chemical driving forces in a multi‐component system are derived on a very general basis. Introducing appropriate expressions for the chemical as well as the mechanical dissipation based on jump conditions of quantities such as the deformation rate and the diffusive fluxes at the moving interface allows to formulate proper transformation criteria. No fluxes will occur in the case of displacive, i.e. martensitic transformation which is responsible for the TRIP phenomenon. The mechanism governing the selection of a particular martensitic variant of the product phase out of a discrete number of possible variants is described in the paper. The underlying ideas and tools supplied by continuum mechanics eventually leading to a transformation condition for martensitic transformation are summarised in the appendix. The second section of the paper shows some aspects of a comprehensive experimental program investigating the thermo‐mechanical behaviour of a maraging steel with very advantageous properties in the transformation regime. It allows to filter out the TRIP strain evolution during transformation from the total strain measured by means of a multiaxial tension torsion dilatometer equipment. The focus is put on finding a material law that is valid also for non‐proportional loading paths. Unlike the predictions of traditional constitutive relationships the TRIP strain rate exhibits a significant drop if the external load is removed during the progress of transformation suggesting the existence of a transformation related backstress. Finally a method is demonstrated how to validate the experimental findings by means of a numerical algorithm. Based on the physical principles explained in the first part of the paper a subroutine can be devised and implemented into a commercial finite element code that allows to simulate the behaviour of the material represented by a unit cell. The simulations yield realistic results for the transformation kinetics, the load‐displacement curves as well as the material response for non‐proportional loading paths. 相似文献
89.
LeGuen D. Favre F. Boittin R. Debeau J. Devaux F. Henry M. Thebault C. Georges T. 《Electronics letters》1995,31(4):301-302
Soliton transmission of a 20 Gbit/s time/polarisation multiplexed signal over 14 Mm path in a recirculating loop with 46.3 km amplification span has been demonstrated using the sliding-filter soliton control technique. Demultiplexing was achieved by using a polarisation-insensitive electroabsorption modulator 相似文献
90.
The aim of the multicenter, randomized, double-blind, double-dummy, parallel-group clinical trial with a 2-week treatment period was to compare the efficacy and safety of salmeterol (50 micrograms twice daily) with slow-release (SR) terbutaline (5 mg orally, twice daily) in nocturnal asthma. A total of 159 asthmatic adults (FEV, 50-90% of predicted value; sex ratio: 0.87) with at least two nocturnal awakenings during a 7-d run-in period was included in the study. Patients were centrally randomized with a national computer network (Minitel). The main variable (number of awakening-free nights during the last week of treatment) was analyzed according to a sequential method with the one-sided triangular test. The number of awakening-free nights (+/- SD) was significantly higher in the salmeterol group: 5.3 +/- 2.4 vs 4.6 +/- 2.3 (P = 0.006). Salmeterol was significantly more effective than SR-terbutaline in the following factors: number of patients without any awakening during the last week of treatment (50% vs 27%, P = 0.003), mean morning PEF (351 +/- 109 l/min-1 vs 332 +/- 105 l/min-1, P = 0.04), PEF diurnal variation 6 +/- 10% vs 11 +/- 12%, P = 0.01), overall assessment of efficacy by the patient and the investigator (P = 0.001 and 0.005, respectively), and daily rescue salbutamol intakes (P = 0.004). In the salmeterol group, significantly fewer patients reported adverse events (16% vs 29%, P = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献