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961.
Lior Miller Amir Avishai Wayne D. Kaplan 《Journal of the American Ceramic Society》2006,89(1):350-353
The solubility of Mg in alumina was measured using wavelength-dispersive spectroscopy mounted on a scanning electron microscope. Careful calibration of the microscope's working conditions was performed in order to optimize the detection limit and accuracy. Measurements were conducted on water-quenched and furnace-cooled samples, without any thermal or chemical etching to avoid alteration of the bulk concentration. The results indicate the solubility limit of Mg in alumina to be 132±11 ppm at 1600°C. 相似文献
962.
Robert D. Miller 《Advanced materials (Deerfield Beach, Fla.)》1989,1(12):433-440
In spite of the fact that the first polysilane derivatives were probably prepared in the mid 1920's, there was little scientific interest until recently. The synthesis of the first soluble homo and copolymers about 10 years ago has stimulated an explosive development of this class of materials. This brief review traces the historical development of the polysilanes and focuses on recent studies of polymer structure, electronic properties, photochemical reactions and mechanisms and finally on new applications. 相似文献
963.
Bushman Brad J.; Bonacci Angelica M.; Pedersen William C.; Vasquez Eduardo A.; Miller Norman 《Canadian Metallurgical Quarterly》2005,88(6):969
Ruminating about a provocation increases the likelihood of displaced aggression following a minor annoyance (trigger). In Study 1, provoked participants who ruminated for 25 min were more aggressive toward a fumbling confederate than were distracted participants. Provocation-induced negative affect was positively related to aggression but only among those who ruminated. Study 2 conceptually replicated Study 1 and also found that the more negatively people reacted to the trigger, the more likely the trigger was to increase displaced aggression. Study 3 replicated the findings of Studies 1 and 2 by using an 8-hr rumination period. All 3 studies suggest that ruminating about a provocation increases the likelihood that a minor triggering annoyance will increase displaced aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
964.
965.
LJ van Rijn MP ten Tusscher I de Jong F Hendrikse 《Canadian Metallurgical Quarterly》1998,38(19):2973-2978
We measured the symmetry of phoria angles in six normal subjects. Subjects were selected on the basis of good visual acuity and stereopsis, normal binocular eye alignment and, apart from mild refraction errors, absence of ocular abnormalities. They were instructed to look at a word on a reading chart at 2 m distance. Each measurement consisted of five subsequent intervals of 5 s duration. During these five intervals viewing was binocular, with the right eye only, binocular, with the left eye only, and binocular, respectively. Each experiment consisted of twelve measurements. Eye movements were measured with scleral coils suited for measuring in horizontal, vertical and torsional directions. Five out of six subjects displayed an asymmetrical vertical phoria; one subject showed an alternating hyperphoria; four displayed a left over right vertical phoria that was largest for left eye occlusion. Only one subject showed a symmetrical vertical phoria. Both the size of the vertical phorias and the size of the asymmetries in these vertical phorias were very small: on average 0.16 +/- 0.01 and 0.17 +/- 0.01 degree, respectively. The direction of the vertical phoria asymmetries (the largest left over right was found with left eye occlusion) and the fact that asymmetries were found more often in vertical than horizontal and torsional phorias suggest that these asymmetries are related to dissociated vertical deviation. These results suggest that dissociated vertical deviation, often observed in subjects with a disruption of binocular vision early in life, reflects the enhancement of a phenomenon that is present in normal subjects as well. 相似文献
966.
SH Miller 《Canadian Metallurgical Quarterly》1998,101(5):1389-1399
Economic constraints developing as a result of rising health care costs in the United States pose significant challenges for and threats to the survival of academic plastic surgery. Declining clinical revenues, competition for patients and resources from other health care providers, and reductions in support of its education and research efforts necessitate a paradigm shift if it is to survive. Questionnaires were used to collect data from 92 of the 100 postgraduate training program directors of plastic surgery in the United States. The most common source of clinical income on a national basis was indemnity insurance. Sources of clinical income varied by region. The majority of programs, 80 percent, report that at least 75 percent of the income support for faculty came from practice income. Financial support for ancillary and research personnel, in large part, came from this same source. Resident salaries and benefits came largely from other resources. Generally as population density within the metropolitan area in which a program was located increased, so too did the number of competing plastic surgeons, including graduates of the program and nonacademic cosmetic and hand surgeons. However, levels of competition for cosmetic surgery in smaller metropolitan areas of some regions seem to be similar to those reported by programs in larger communities. Plastic surgery programs in very competitive communities received significantly greater amounts of their income from indemnity insurance and self-paying patients than did programs in less competitive metropolitan areas. Internal competition from other surgical and nonsurgical specialists within the same institution is likewise keen. Virtually all respondents, 93 percent, report that their institutions provided patient care in a least one designated center of excellence in the following disciplines: hand, microsurgery, craniofacial, cleft lip and palate, burn, and cosmetic surgery. This study suggests that centers of excellence are more likely to be present in metropolitan areas with fewer competing surgeons than in areas with large numbers of competing surgeons. The data did not demonstrate that the presence of a center of excellence substantially affected the sources or levels of clinical income. To survive as an academic entity, program directors must correctly perceive and fulfill the needs and wants of its stakeholders, particularly with regard to quality of life issues. 相似文献
967.
TH Chao LM Tsai JK Teng YH Li WC Tsai LJ Lin JH Chen 《Canadian Metallurgical Quarterly》1998,97(9):638-641
Pica is the persistent, culturally and developmentally inappropriate ingestion of non-nutritive substances (DSM-IV). AB is a 75-year-old lady with a 40-year history of schizophrenia and a 20-year history of pica who, at emergency laparotomy, had 175.32 Pounds of loose change in her stomach. Although pica has been reported to coexist with schizophrenia, she had had no positive symptoms of schizophrenia for at least 20 years. She has CT evidence of fronto-tempotal atrophy most marked on the left in the temporal lobe and on the right in the frontal lobe. Pica has been found to be related to cognitive deficits and hyperoral behaviour to temporal lesions. Neuropsychological testing reveals deficits closely related to these changes. 相似文献
968.
PURPOSE: To corroborate the findings of finger-like membrane projections in monkey and baboon lenses, in human lens fiber cells. METHODS: Normal human lenses, two months to 76 years old, as well as age-related nuclear cataracts, were immersion fixed in 2% paraformaldehyde-0.2% glutaraldehyde in 0.1 M sodium cacodylate buffer pH 7.2 for 24 h at room temperature, cut into 200-500 microm thick sections along the equatorial axis, fixed for an additional 12-18 h at room temperature, dehydrated in an ascending ethanol series and embedded in Lowicryl K4M. Semi-thick sections (0.25-1.0 microm) were cut, absorbed onto 75 or 100 nickel slotted grids, labeled with anti-MIP 26 or phalloidin, stained with 2% uranyl acetate and viewed by transmission electron microscopy at 100 kV. RESULTS: Transmission electron microscopy micrographs demonstrated the presence of finger-like plasma membrane projections measuring 0.16-0.25 microm in diameter and 1.0-6.5 microm in length with bulbous terminal tips in the most senescent fiber cells in two-month and older normal lenses, as well as, in nuclear cataracts. These projections appeared to overlie furrowed membrane domains in the extracellular space, as well as project into the cytosol along the cytosolic leaflet of plasma membrane. CONCLUSIONS: The results extend the findings in monkey and baboon lenses, to the human lens, and demonstrate that these projections, which sparsely label with antiserum against MIP 26, but not filamentous actin, not only extend into the extracellular space, but also project inward into the cytosol. 相似文献
969.
Several species of the genus Haemophilus are well known etiological agents of pneumonia, meningitis, conjunctivitis, epiglottitis and chancroid. However, identification and speciation of Haemophilus is both time consuming and labor intensive. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF-MS) has been used by several investigators to profile proteins from intact and disrupted bacteria; consequently, MALDI/TOF-MS has emerged as a powerful tool in diagnostic bacteriology. This paper reports the use of MALDI/TOF-MS as a technique for the rapid identification and speciation of Haemophilus. This technique was used to not only identify the pathogen, H. ducreyi, but also to determine strain differences from different isolates. Mass spectral 'fingerprints' were obtained which permitted the rapid speciation of not only pathogenic forms of Haemophilus, but also those bacteria which are normally regarded as non-pathogenic and members of the normal flora. MALDI/TOF mass spectra can be acquired in 10 min, allowing the identification of Haemophilus spp. within 24 h rather than the 48 h or more needed for traditional bacteriological methods. In addition, these are the first mass spectral fingerprints available in the literature for many of these organisms. 相似文献
970.