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91.
Bartlett James C.; Shastri Kalyan K.; Abdi Hervé; Neville-Smith Marsha 《Canadian Metallurgical Quarterly》2009,35(5):1207
Principal-component analyses of 4 face-recognition studies uncovered 2 independent components. The first component was strongly related to false-alarm errors with new faces as well as to facial “conjunctions” that recombine features of previously studied faces. The second component was strongly related to hits as well as to the conjunction/new difference in false-alarm errors. The pattern of loadings on both components was impressively invariant across the experiments, which differed in age range of participants, stimulus set, list length, facial orientation, and the presence versus absence of familiarized lures along with conjunction and entirely new lures in the recognition test. Taken together, the findings show that neither component was exclusively related to discrimination, criterion, configural processing, featural processing, context recollection, or familiarity. Rather, the data are consistent with a neuropsychological model that distinguishes frontal and occipitotemporal contributions to face recognition memory. Within the framework of the model, findings showed that frontal and occipitotemporal contributions are discernible from the pattern of individual differences in behavioral performance among healthy young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
We report the formation of hybrid metallopolymer microspheres, deposited from an acetonitrile solution containing a known iron(3+) spin crossover complex bearing a thienyl substituent. We characterize the metallopolymer using SEM, FT-IR, elemental analysis (including C, H, N, S, Fe analyses), small-angle X-ray scattering (SAXS) techniques, and PXRD. Of greatest significance, the polymeric microspheres also exhibit spin crossover, conferring on metallopolymer 2 the first spin crossover nanoscale material of its kind. 相似文献
93.
Nanoscale precipitation and mechanical properties of Al-0.06 at.% Sc alloys microalloyed with Yb or Gd 总被引:2,自引:0,他引:2
Marsha E. van Dalen David C. Dunand David N. Seidman 《Journal of Materials Science》2006,41(23):7814-7823
Dilute Al-0.06 at.% Sc alloys with microalloying additions of 50 at. ppm of ytterbium (Yb) or gadolinium (Gd) are studied with 3D local-electrode atom-probe (LEAP) tomography for different aging times at 300 °C. Peak-aged alloys exhibit Al3(Sc1−x
Yb
x
) or Al3(Sc1−x
Gd
x
) precipitates (L12 structure) with a higher number density (and therefore higher peak hardness) than a binary Al-0.06 at.% Sc alloy. The Al–Sc–Gd alloy exhibits a higher number density of precipitates with a smaller average radius than the Al–Sc–Yb alloy, leading to a higher hardness. In the Al–Sc–Gd alloy, only a small amount of the Sc is replaced by Gd in the Al3(Sc1−x
Gd
x
) precipitates, where x = 0.08. By contrast, the hardness incubation time is significantly shorter in the Al–Sc–Yb alloy, due to the formation of Yb-rich Al3(Yb1−x
Sc
x
) precipitates to which Sc subsequently diffuses, eventually forming Sc-rich Al3(Sc1−x
Yb
x
) precipitates. For both alloys, the precipitate radii are found to be almost constant to an aging time of 24 h, although the concentration and distribution of the RE elements in the precipitates continues to evolve temporally. Similar to microhardness at ambient temperature, the creep resistance at 300 °C is significantly improved by RE microalloying of the binary Al-0.06 at.% Sc alloy. 相似文献
94.
MacDonald-Wilson Kim L.; Rogers E. Sally; Ellison Marsha Langer; Lyass Asya 《Canadian Metallurgical Quarterly》2003,48(4):301
Objective: To study use and awareness of the Social Security Work Incentives (SSWIs) and to obtain empirical data on barriers to returning to work. Study Design: Using parallel surveys and multiple sampling and recruitment strategies, the authors administered a brief survey about the SSWIs. Participants: Persons with a psychiatric disability (n=539), service providers (n=120), and family members (n=174). Results: All groups registered the greatest concern about the loss of health insurance; this and other concerns were perceived as serious barriers to returning to work. There were differences in the perceptions of the 3 groups about the importance of disincentives to work and differences among consumers by demographic characteristics. Conclusions: Consumers, family members, and providers of services need more information about the work incentives, particularly if the goals of the new Ticket to Work legislation are to be realized. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Opportunistic pathogens in potable water systems are an emerging health concern; however, the factors influencing their proliferation are poorly understood. Here we investigated the effects of prior granular activated carbon (GAC) biofiltration [GAC-filtered water, unfiltered water, and a blend (30% GAC filtered and 70% unfiltered water)] and disinfectant type (chlorine, chloramine) on opportunistic pathogen occurrence using five annular reactors (ARs) to simulate water distribution systems, particularly premise plumbing. GAC pre-treatment effectively reduced total organic carbon (TOC), resulting in three levels of influent TOC investigated. Quantitative polymerase chain reaction (q-PCR) provided molecular evidence of natural colonization of Legionella spp., Mycobacterium spp., Acanthamoeba spp., Hartmannella vermiformis and Mycobacterium avium on AR coupons. Cultivable mycobacteria and amoeba, including pathogenic species, were also found in bulk water and biofilm samples. While q-PCR tends to overestimate live cells, it provided a quantitative comparison of target organisms colonizing the AR biofilms in terms of gene copy numbers. In most cases, total bacteria and opportunistic pathogens were higher in the three undisinfected ARs, but the levels were not proportional to the level of GAC pre-treatment/TOC. Chlorine was more effective for controlling mycobacteria and Acanthamoeba, whereas chloramine was more effective for controlling Legionella. Both chlorine and chloramine effectively inhibited M. avium and H. vermiformis colonization. Pyrosequencing of 16S rRNA genes in coupon biofilms revealed a significant effect of GAC pre-treatment and disinfectant type on the microbial community structure. Overall, this study provides insights into the potential of different disinfectants and GAC biofilters at the treatment plant and in buildings to control downstream opportunistic pathogens and broader drinking water microbial communities. 相似文献
96.
A new gelcasting system based on aqueous alumina (Al2 O3 )–poly(vinyl alcohol) (PVA) suspensions cross-linked via titanium ion complexation has been developed as a feedstock for bulk casting and solid freeform fabrication (SFF) routes. Its chemorheological properties, as measured by stress viscometry and oscillatory techniques, exhibited a strong dependence upon polymer hydrolysis and molecular weight. The gelation time of systems of constant PVA volume fraction (φPVA soln ) and cross-linker concentration decreased with increasing degree of hydrolysis and molecular weight, whereas their steady-state elastic modulus ( G' ) exhibited the opposite dependence. Stress evolution during drying of gelcast layers was measured in situ using a controlled-environment, cantilever deflection apparatus. Both the maximum and residual drying stresses increased with increasing degree of hydrolysis, with only a modest molecular weight effect observed. 相似文献
97.
Interactions between the glass and crystalline phases of ceramic waste forms were investigated via powder X-ray diffraction, scanning electron microscopy, and 29 Si, 27 Al, 23 Na, 7 Li, and 35 Cl magic angle spinning nuclear magnetic resonance spectroscopy. LiCl, NaCl, or KCl waste form samples were made with or without glass. The waste forms containing glass consist of sodalite and glass phases with minor amounts of nepheline. Samples without glass form varying amounts of sodalite and nepheline. The glass frit, intended to bind the zeolite particles together, changes in composition, showing marked increases in aluminum and alkali content. 相似文献
98.
Bates Marsha E.; Pawlak Anthony P.; Tonigan J. Scott; Buckman Jennifer F. 《Canadian Metallurgical Quarterly》2006,20(3):241
Serious neuropsychological impairments are seen in a minority of addiction treatment clients, and, theoretically, these impairments should undermine behavioral changes targeted by treatment; however, little evidence supports a direct influence of impairment on treatment response. To address this paradox, the authors used structural equation modeling and Project MATCH data (N=1,726) to examine direct, mediated, and moderated paths between cognitive impairment, therapeutic processes, and treatment outcome. Mediated relations were found, wherein impairment led to less treatment compliance, lower self-efficacy, and greater Alcoholics Anonymous Involvement, which, in turn, more proximally predicted drinking. Impairment further moderated the effect of self-efficacy, making it a poor predictor of drinking outcomes in impaired clients, thereby suggesting that impaired and unimpaired clients traverse different pathways to addiction recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Marsha Siefert 《The Journal of communication》2003,53(2):365-373
100.
Marsha Ritzdorf 《Journal of Urban Affairs》1987,9(1):79-89
ABSTRACT: Current federal policies have favored the resource needs of the elderly over the needs of child rearing families and children. Yet, federal policies are only part of the story. Can healthy intergenerational communities become a reality ? Is it possible for municipalities to help restore some balance in meeting the resource needs of the young and the old? The purpose of this article is to evaluate municipal land use, planning and zoning policies and the roles they play in meeting the needs of children and the elderly in contemporary American communities. Data collected in a nationwide zoning survey will be used to support the argument that communities are doing little to respond to the changing needs of child rearing and elderly families. The article concludes with a discussion of change strategies that could help make healthy intergenerational communities a reality. 相似文献