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Objective@#To investigate the influence of unitization encoding strategy and the moderating effect of unitization level on directed forgetting effect of associative recognition.@*Methods@#Association recognition paradigm combined with directed forgetting paradigm were employed in this study.The 39 participants acquired by simple random sampling were asked to remember or forget compound words or unrelated word pairs which were randomly presented according to cues.In the retrieval stage, they needed to distinguish " old" or " rearranged" word pairs regardless of the cues.@*Results@#(1) The reversed unitization effect reached significance. The discrimination of compound words (0.43±0.03) was lower than that of unrelated words (0.55±0.03) (F=27.27, P<0.001, ηp2=0.42). For the word pairs (to be remembered, TBR), the discrimination of compound words (0.43±0.03) was lower than that of unrelated words (0.59±0.03) (t=-6.05, P<0.001); for the word pairs (to be forgotten, TBF), the discrimination of compound words (0.43±0.03) was still lower than that of unrelated words (0.50±0.04) (t=-2.30, P=0.025). (2) The directed forgetting effect of associative recognition was significant.However, TBR (0.51±0.03) was more discriminative than TBF (0.46±0.03) (F=4.30, P=0.045, ηp2=0.10). But the difference was mainly reflected in the recognition of unrelated words.TBR (0.59±0.03) was more discriminative than TBF (0.50±0.04) (t=3.19, P=0.003). However, there was no significant difference between TBR (0.43±0.03) and TBF (0.43±0.03) in recognition of compound words.@*Conclusion@#The unitization encoding stratege can simultaneously promote hit rate and false alarm rate.The directed forgetting effect can be eliminated when unitization level is high enough.
ABSTRACT
BACKGROUND:For reducing the stress shielding, a lot of the schemes have adopted, and there is no great improvement although via the trial and the application for several ten years. It comes from a root which is the combination by thigh bone (abbreviation of the bone) and metal ic handle (abbreviation of the handle) which causes the serious problems of absorption of bone quality, and this kind of stress shielding effect is produced by abnormal stress and abnormal strain, and affected by various factors, so there is no effective and applicable method to solve this problem. OBJECTIVE:To select the primary porous layer scheme as the subject of the study and entirely change the appearance and inherent quality as the metal ic handle that cannot transmit the stress is the key to eliminate the stress shielding;making the senior porous layer with the effective measure is the basis to eliminate stress shedding and can solve the disaster and partial inferior position aroused by the primary porous layer. METHODS:The cobalt-chromium-molybdenum al oy smal metal ic spherules with equal diameter were used to manufacture the senior porous layer structure. The structural member employed in the thigh bone could separate the handle from the bone. This structural member welded on the plane of bone neck could fix the handle with calcar osteotomy surface. And these structural members had an ability to eliminate al the stress shieldings on the artificial hip joint surface. RESULTS AND CONCLUSION:The senior porous layer was made with cobalt-chromium-molybdenum al oy smal metal ic spherules with the same diameter (1.00-1.29 mm), and the surface of the porous layer was plated with high property of medium layer al oy and arranged orderly and inseparable, and then connected with active diffusion welding technology. The diameter of al the holes was 155-200μm and distributed evenly which was benefit for the bone unit to grew. The al oying of metal materials, ceramic of al oy surface and control ing of size and number of wear particles can solve the bone dissolution of the surrounding porous layer of bone, metal dissolution as wel as its pure cobalt and chromium particle toxicity, cancerization and leukemia. A stipulation of theoretical basis was to eliminate the handle rigidity firstly that could made the separation of handle from the bone became the premise for eliminating the stress shielding. The calcar osteotomy surface grew into the pores of the structural member welded on plane of bone neck could fix the handle, and that was the basis for eliminating the stress shielding. The common roles can eliminate the stress shielding in thigh bone, and the stress shielding on acetabulum is easily to eliminate.
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OBJECTIVE: Sintering of porous coated anatomic porous layer bonding technology remains controversial because of poor understanding to its essence.ESSENCE: Sintering is a technology that the bonding temperature exceeds 5 ℃ or higher than the base-alloy solids temperature of 1 230 ℃, resulting in base-alloy produce a series of serious problems, such as grain boundary racks, handle broken and so on.HAZARDS: In sintering temperature, the low melting point eutectlc phase and the brittle metal compounds flow out of the grain boundary to bond the small metal balls and the handle, which greatly reduces the fatigue strength. The grain boundary cracks formed and expanded ultimately leading to handle broken.DISCUSSION: The cause of a handle broken is neither notch nor metallurgical defects but sintering process, because high sintering temperature results in grain-boundary lacunas.CONCLUSION: Sintering is not suitable for connecting the force components. High sintering temperature produces grain-boundary lacunas which can expand into cracks and ultimately result in handle broken under some condition.
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INTRODUCTION: General joining techniques are at low level, which produces some potential problems in porous layer of porous coated anatomic (PCA).LIMITATIONS: The problems in general joining techniques are caused by limitations of each technique, which could not be solved using advanced measures.APPLICATION: The activated diffusion brazing technology is an effective way. Its many advanced processes can solve those potential problems.CONCLUSION: The stress-shielding problem caused by PCA porous layer can be solved by using small metal balls in the same diameter in combination with the advanced activated diffusion brazing technology. Moreover, the high performance brazing metals by activated diffusion brazing technology is harmless for humans.
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A broken metal handle accompanied by femoral trunk fracture, which would shorten service life of handles. Therefore, it is necessary to judge whether the notch is the main reason for handle broken. Some literatures thought that the pores of sintered porous coated anatomic (PCA) porous layer produce the notch on the handle surface and the notches lead to the handle broken being incorrect. The Apex of the pore is taken for the bottom of the notch, expanding into a crack, and it should also not grow to the base-alloy, accordingly, the above conclusion is wrong. Some reports pointed out the notch, apex of the pore, will expand into the crack, but it is not associated with the broken handle. Under the sintering temperature, the grain boundary apertures be generated on the base metal surface, the aperture is expanded into the crack, which leads to handle broken in the forced area. However, neither theoretical basis, nor a case of corroboration, can prove exist of notch. Actually, the broken handle is caused by the sintering technology. The high temperature of sintering joining results in grain boundary aperture, when encounter the largest forced area and expand into crack, it will break the handle.