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31.
32.
Salthouse Timothy A.; Toth Jeffrey; Daniels Karen; Parks Colleen; Pak Richard; Wolbrette Michelle; Hocking Kellie J. 《Canadian Metallurgical Quarterly》2000,14(1):102
The Trail Making Test [TMT, R. M. Reitan, (see record 1960-00397-001), 1992] is extensively used in research in neuropsychology and in aging, in part because it has been postulated to reflect executive processes, such as planning and switching. However, neurocognitive and individual-difference based analyses of this test are complicated because of different spatial arrangements of targets, the use of letters only in Version B, and potential order effects when Version A is administered prior to Version B. The present article examines a variant of a TMT (called the Connections Test) that attempts to remedy these deficiencies. A structural equation model suggested that there were no direct effects of age on either the nonalternating or alternating versions of the Connections Test (analogous to TMT Versions A and B, respectively); rather, all age-related effects were mediated through effects on perceptual speed. Moreover, although the nonalternating and alternating versions were strongly related to one another, only the latter had significant independent relations with measures of higher order cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Study on the soldering in partial melting state (1) analysis of surface tension and wettability 总被引:2,自引:0,他引:2
Jae Yong Park Jun Seok Ha Choon Sik Kang Kyu Sik Shin Moon Il Kim Jae Pil Jung 《Journal of Electronic Materials》2000,29(10):1145-1152
This paper introduces the partial melting process for solder application and characterization of its feasibility using Pb-Sn,
Ag-Sn, Sn-Cu, Sn-In and Sn-Bi alloys. In order to show that the liquid phase in the semi-liquid state maintains the similar
wettability as the single-phase liquid, the wetting balance tests are conducted with varying temperatures and compositions.
The results are then compared with the surface tension of liquid, both measured and calculated, to examine the correlation.
The results from this investigation indicate that the partial melting can yield satisfactory solder joints as long as the
liquid phase acquires sufficient chemical activity. At a condition where the partial melting is effective, a direct correlation
between the wettability and the surface tension is found to exist. All alloys except two, Sn-Bi and Sn-In, are found to show
a reasonable wettability in semi-liquid state. 相似文献
34.
Retinol binding protein 4 (RBP4) is a useful biomarker in the diagnosis of type 2 diabetes since its level in the serum is higher in insulin-resistant states. Accurate measurement of the serum RBP4 levels is hampered by conventional immunologic methods, such as enzyme-linked immunosorbent assay (ELISA). In this study, therefore, we have developed an aptamer-based surface plasmon resonance (SPR) biosensor that can be used to sense for RBP4 in serum samples. A single-stranded DNA (ssDNA) aptamer that showed high affinity (Kd = 0.2 +/- 0.03 microM) and specificity to RBP4 was selected. This RBP4-specific aptamer was immobilized on a gold chip and used in a label-free RBP4 detection using SPR. Analysis of RBP4 in artificial serum using SPR was compared with ELISA and Western blot analysis. Our results indicated that the RBP4-specific aptamer-based SPR biosensor gave better dose-dependent responses and was more sensitive than ELISA assays. As such, this RBP4 aptamer-based SPR biosensor can be potentially used to monitor the RBP4 levels within the serum as an indicator of type 2 diabetes. 相似文献
35.
Elizabeth?A?Magee Laurie?M?EdmondEmail author Shiona?M?Tasker San?Choon?Kong Richard?Curno John?H?Cummings 《Nutrition journal》2005,4(1):7
Background
The relapsing nature and varying geographical prevalence of ulcerative colitis (UC) implicates environmental factors such as diet in its aetiology. 相似文献36.
37.
Microsystem Technologies - Offline iterative control technique in a hydraulic testing sector is primarily used to improve the tracking control performance despite nonlinearity caused by a testing... 相似文献
38.
Each piece of equipment in an electrical system is a potential source of transient voltages. At the same time, it also has some degree of susceptibility to transient voltages. This paper discusses the allowable limits of transient voltages generated by each piece of equipment and the total system, and the susceptibility of each piece of equipment and the system. For satisfactory operation of a system, the allowable limits of the generated transient voltages should be coordinated with the specified susceptibility of each piece of equipment as well as the system. The coordinated protection of an electrical system is the joint responsibility of the equipment designer and the systems engineer. Techniques to measure susceptibility are also described. 相似文献
39.
40.
Byung-Yeon Choi Yusin Pak Ki Seok Kim Kwang-Ho Lee Gun-Young Jung 《Nanoscale research letters》2011,6(1):449
We have demonstrated simultaneous fabrication of designed defects within a periodic structure. For rapid fabrication of periodic structures incorporating nanoscale line-defects at large area, topographically assisted holographic lithography (TAHL) technique, combining the strength of hologram lithography and phase-shift interference, was proposed. Hot-embossing method generated the photoresist patterns with vertical side walls which enabled phase-shift mask effect at the edge of patterns. Embossing temperature and relief height were crucial parameters for the successful TAHL process. Periodic holes with a diameter of 600 nm at a 1 μm-pitch incorporating 250 nm wide line-defects were obtained simultaneously. 相似文献