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31.
For tensile stresses applied parallel to the elongated grain structure of the aluminum alloy, 8090, the creep and creep fracture
properties are discussed in relation to the changes in precipitate dispersion and transgranular failure mode observed over
stress ranges giving creep lives up to 6000 hours at 373 to 463 K. Specifically, a transition from growth of cracks nucleating
on the short transverse boundaries to neck formation occurs when the deformation resistance is reduced progressively by precipitate
coarsening as the test duration increases at 427 K and above. All features of the recorded behavior patterns are then explained
in terms of the processes governing strain accumulation and damage development by using the ϑ methodology to quantify the systematic variations in creep curve shape with changing stress and temperature. 相似文献
32.
CJ Link RK Burt AE Traynor WR Drobyski T Seregina JP Levy L Gordon ST Rosen WH Burns B Camitta J Casper M Horowitz M Juckett C Lawton D Margolis D Pietryga P Rowlings C Taylor M Furtado J Stefka S Gupta-Burt H Kaiser DH Vesole 《Canadian Metallurgical Quarterly》1998,9(1):115-134
This study will evaluate the safety and efficacy of allogenic donor lymphocyte infusions in patients who have relapsed hematologic malignancies after allogeneic bone marrow transplantation (BMT). Donor lymphocyte transfusions have resulted in the cure of some patients with relapsed leukemia or lymphoproliferative disorder after allogeneic BMT, but has been complicated by the development of graft versus host disease (GvHD). We hypothesize that a retroviral vector containing the Herpes simplex thymidine kinase (HStk) gene will allow for retention of the anti-leukemia response of transfused donor lymphocytes while allowing for the adverse effects of GVHD to be mitigated. Patients with relapsed hematologic malignancies after allogeneic BMT will be infused with ex vivo gene modified donor lymphocytes. The Herpes Simplex thymidine kinase (HStk) gene will be transduced into the cells ex vivo using LTKOSN. 1 vector supernate. Insertion of the HStk gene into lymphocytes confers a sensitivity to the anti-herpes drug ganciclovir (GCV). This selective destruction of donor lymphocytes in situ will be used to abrogate the effect of graft versus host disease, if it develops. 相似文献
33.
34.
Reports an error in "Improved Bonferroni-type multiple testing procedures" by Burt S. Holland and Margaret D. Copenhaver (Psychological Bulletin, 1988[Jul], Vol 104[1], 145-149). An error was made in the author note on page 145. Correspondence should be addressed to Burt S. Holland, Department of Statistics, Temple University, Speakman Hall (006-00), Philadelphia, Pennsylvania 19122. Margaret DiPonzio Copenhaver is now at Merck Sharp & Dohme Research Laboratories, West Point, Pennsylvania. (The following abstract of the original article appeared in record 1988-34705-001.) The Bonferroni multiple comparisons procedure is customarily used when doing several simultaneous tests of significance in relatively nonstandard situations in which other methods do not apply. We review some new and improved competitors to the Bonferroni procedure, that although constraining generalized Type I error probability to be at most α, afford increased power in exchange for increased complexity in implementation. An improvement to the weighted form of the Bonferroni procedure is also presented. Several data sets are reanalyzed with the new methods. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
Anesthesiologists should approach the airway carefully in the patient with a diagnosis of head and neck carcinoma, particularly if the patient has had previous surgery and reconstruction. Patients with head and neck carcinoma may be difficult intubations due to altered anatomy from the tumor or fibrotic changes because of radiation therapy. Our patient had had pharyngectomy and reconstruction with a pectoralis major skin flap. The patient returned to the operating suite for wide-excision pharyngectomy and had acute airway obstruction after induction of general anesthesia. The pectoralis flap had necrosed, pulling away from the pharyngeal wall and obstructing the patient's glottic opening. 相似文献
36.
Tested hypotheses derived from social psychological and feminist theory that acceptance of rape myths can be predicted from attitudes such as sex role stereotyping, adversarial sexual beliefs, sexual conservatism, and acceptance of interpersonal violence. Personality characteristics, background characteristics, and personal exposure to rape, rape victims, and rapists are other factors used in predictions. Results from regression analysis of interview data from 598 randomly selected adults indicate that the higher the sex role stereotyping, adversarial sexual beliefs, and acceptance of interpersonal violence, the greater an S's acceptance of rape myths. In addition, younger and better educated Ss revealed fewer stereotypic, adversarial, and proviolence attitudes and less rape myth acceptance. Implications for understanding and changing this cultural orientation toward sexual assault are discussed. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
J Groden L Gelbert A Thliveris L Nelson M Robertson G Joslyn W Samowitz L Spirio M Carlson R Burt 《Canadian Metallurgical Quarterly》1993,52(2):263-272
Samples of constitutional DNA from 60 unrelated patients with adenomatous polyposis coli (APC) were examined for mutations in the APC gene. Five inactivating mutations were observed among 12 individuals with APC; all were different from the six inactivating mutations previously reported in this panel of patients. The newly discovered mutations included single-nucleotide substitutions leading to stop codons and small deletions leading to frameshifts. Two of the mutations were observed in multiple APC families and in sporadic cases of APC; allele-specific PCR primers were designed for detecting mutations at these common sites. No missense mutations that segregated with the disease were found. 相似文献
38.
Fluctuation analysis allows for the determination of mutation rates in cell cultures in vitro. As originally described by Luria and Delbruck and extended by Lea and Coulson and by Capizzi and Jameson, this analysis has been useful in estimating mutation rates in cultured cells where the frequency of mutational events is low. However. in cultures where high mutation rates and multiple independent mutation events occur, leading to the accumulation of many mutant cells, these standard methods may not apply. Here, we present a new method for the estimation of mutation rates based on the assumption that multiple events may contribute to the accumulation of mutant cells. We compared mutation rates determined by Lea and Coulson's and by Capizzi and Jameson's methods with those determined by our method using experimental and stimulated data from our studies of immunoglobulin gene mutation and isotype switching in B lymphocyte cultures. The three methods resulted in very different calculated rates when many mutants were present in the culture, such as when mutation rates were high, while only small differences in calculated rates were found when mutants were rare. Unlike previous fluctuation analysis calculations, our method is applicable for the estimation of both low and high rates. 相似文献
39.
40.
In an effort to establish a more reliable set of optical cross sections for a variety of chemical and biological aerosol simulants, we have developed a flow-through photoacoustic system that is capable of measuring absolute, mass-normalized extinction and absorption cross sections. By employing a flow-through design we avoid issues associated with closed aerosol photoacoustic systems and improve sensitivity. Although the results shown here were obtained for the tunable CO2 laser waveband region, i.e., 9.20-10.80 microm, application to other wavelengths is easily achievable. The aerosols considered are categorized as biological, chemical, and inorganic in origin, i.e., Bacillus atrophaeus endospores, dimethicone silicone oil (SF-96 grade 50), and kaolin clay powder (alumina and silicate), respectively. Results compare well with spectral extinction measured previously by Fourier-transform infrared spectroscopy. Comparisons with Mie theory calculations based on previously published complex indices of refraction and measured size distributions are also presented. 相似文献