Measuring the Depth Perception Invoked by a Simple, Sustained, Polarity-Reversed Stereogram

The same-sign hypothesis suggests that only those edges in the two retinal images whose luminance gradients have the same sign can be stereoscopically fused to generate a perception of depth. If true, one would expect that the magnitude of the depth induced by a polarity-reversed stereogram (i.e. one where the corresponding figures in the two stereo half images have opposite luminance polarity) should be determined by the disparity of the samesign edges. Here we present a simple, sustained, polarity-reversed stereogram which we believe to be the first example of a polarity-reversed stereogram where this prediction is shown to be true. We conclude by discussing possible reasons why this prediction fails for other polarity-reversed stereograms.Defense Research Projects Agency and the Office of Naval Research (N00014-95-1-0409); Office of Naval Research (N00014-95-1-0657); National Science Foundation (SBR-9905194)

Greater Disruption Due to Failure of Inhibitory Control on an Ambiguous Distractor

Considerable evidence indicates that a stimulus that is subthreshold, and thus consciously invisible, influences brain activity and behavioral performance. However, it is not clear how subthreshold stimuli are processed in the brain. We found that a task-irrelevant subthreshold coherent motion led to a stronger disturbance in task performance than did suprathreshold motion. With the subthreshold motion, activity in the visual cortex measured by functional magnetic resonance imaging was higher, but activity in the lateral prefrontal cortex was lower, than with suprathreshold motion. These results suggest that subthreshold irrelevant signals are not subject to effective inhibitory control

Structural diversity and evolution of the N-terminal isoform-specific region of ecdysone receptor-A and -B1 isoforms in insects

<p>Abstract</p> <p>Background</p> <p>The ecdysone receptor (EcR) regulates various cellular responses to ecdysteroids during insect development. Insects have multiple EcR isoforms with different N-terminal A/B domains that contain the isoform-specific activation function (AF)-1 region. Although distinct physiologic functions of the EcR isoforms have been characterized in higher holometabolous insects, they remain unclear in basal direct-developing insects, in which only A isoform has been identified. To examine the structural basis of the EcR isoform-specific AF-1 regions, we performed a comprehensive structural comparison of the isoform-specific region of the EcR-A and -B1 isoforms in insects.</p> <p>Results</p> <p>The EcR isoforms were newly identified in 51 species of insects and non-insect arthropods, including direct-developing ametabolous and hemimetabolous insects. The comprehensive structural comparison revealed that the isoform-specific region of each EcR isoform contained evolutionally conserved microdomain structures and insect subgroup-specific structural modifications. The A isoform-specific region generally contained four conserved microdomains, including the SUMOylation motif and the nuclear localization signal, whereas the B1 isoform-specific region contained three conserved microdomains, including an acidic activator domain-like motif. In addition, the EcR-B1 isoform of holometabolous insects had a novel microdomain at the N-terminal end.</p> <p>Conclusions</p> <p>Given that the nuclear receptor AF-1 is involved in cofactor recruitment and transcriptional regulation, the microdomain structures identified in the isoform-specific A/B domains might function as signature motifs and/or as targets for cofactor proteins that play essential roles in the EcR isoform-specific AF-1 regions. Moreover, the novel microdomain in the isoform-specific region of the holometabolous insect EcR-B1 isoform suggests that the holometabolous insect EcR-B1 acquired additional transcriptional regulation mechanisms.</p

Relevance, Reflexibility and Context of the Cost Accounting System : A Viewpoint of Cost Accounting Change

We have argued that cost accounting system should be modified in accordance with the purpose for using them and the context. Because no cost accounting system that is relevant in every business or environment exists. Relevant cost accounting system is determined in a particular environment and context. This mode of thought relates directly to proposition which develops to explain the theory of 'cost accounting change'. This paper examines the relationships among the purpose, reflexibility and contexts of cost accounting system. The analysis based on reflexibility theory and some previous studies for activity-based costing and contingency theory indicated that: 1) Actual reflexibility about existing cost accounting was associated with two contextual variables: product diversity and process complexity. 2) A reflexibility required mainly through the purpose for using cost accounting was associated with two contextual variables: competitive strategy and perceived environment uncertainty. Finally, we concluded that the relevance of cost accounting was lost and 'cost accounting change' became necessary when the level of actual reflexibility didn't fit that of required reflexibility

Interference and feature specificity in visual perceptual learning

AbstractPerceptual learning (PL) often shows specificity to a trained feature. We investigated whether feature specificity is related to disruption in PL using the texture discrimination task (TDT), which shows learning specificity to background element but not to target element. Learning was disrupted when orientations of background elements were changed in two successive training sessions (interference) but not in a random order from trial to trial (roving). The presentation of target elements seemed to have reversed effect; learning occurred in two-parts training but not with roving. These results suggest that interference in TDT is feature specific while disruption by roving is not

<臨床>胃切除術後の単位体積当たりの骨密度の変化 : Dual energy X-ray absorptiometry (DXA) 法による検討

We used dual energy X-ray absorptiometry (DXA) to study changes in estimated volumetric bone mineral density (EstVBMD) of the lumbar spine after gastrectomy. The study group comprised 41 men and 32 women. When EstVBMD was compared according to sex among patients younger than 60 years of age, patients 60 to 69 years of age, and patients these three groups in men (0.185 g/cm_3, 0.187 g/cm_3, 0.187 g/cm_3, respectively). In contrast , EstVBMD was significantly lower in women 60 to 69 years of age (0.157 g/cm_3) and those 70 years of age or older (0.159 g/cm_3) than in women younger than 60 years (0.200 g/cm_3) (P<0.01). When the relation between EstVBMD and the number of months after gastrectomy was studied according to sex in patients younger than 70 years, EstVBMD negatively correlated with the interval after operation in men (r= -0.365, P<0.05), whereas ther e was no correlation between these variables in women. These results suggest that after gastrectomy bone mineral density decreases gradually in men younger than 70 years, but not in women. The lack of a consistent change in bone mineral density after gastrectomy in women is apparently caused by the marked effect on bone metabolism of decreased female hormone levels after menopause.胃切除後の腰椎の骨密度の変化を dual energy X-ray absorptiornetory （DXA） 法で測定し, 単位体積当たりの計測値（Estimated volumetric bone mineral density: EstVBMD）を求めることにより検討した. 男女別に60歳未満, 60歳代, 70歳以上の群で比較すると, 男性では 0.185 g/cm_3, 0.187 g/cm_3, 0.187 g/cm_3と大差がなかった. 一方, 女性では 0.200 g/cm_3, 0.157 g/cm_3, 0.159 g/cm_3 と60歳未満の症例と比較し60歳代, 70歳以上の症例では減少し有意差を認めた. 70歳未満の症例で男女別に術後月数と骨密度との関係をみると, 男性では経過期間とともに骨密度は減少し, 負の相関関係 （r= -0.365, P<0.05）が認められたが, 女性では両者は独立した関係であった. 70歳未満の男性では胃切術後に徐々に骨塩量が低下するが, 女性では閉経後の女性ホルモン減少が強く骨代謝に現れるため胃切術後の影響が個々で異なることが示唆された

Location-Specific Cortical Activation Changes during Sleep after Training for Perceptual Learning

Visual perceptual learning is defined as performance enhancement on a sensory task and is distinguished from other types of learning and memory in that it is highly specific for location of the trained stimulus. The location specificity has been shown to be paralleled by enhancement in functional magnetic resonance imaging (fMRI) signal in the trained region of V1 after visual training. Although recently the role of sleep in strengthening visual perceptual learning has attracted much attention, its underlying neural mechanism has yet to be clarified. Here, for the first time, fMRI measurement of human V1 activation was conducted concurrently with a polysomnogram during sleep with and without preceding training for visual perceptual learning. As a result of predetermined region-of-interest analysis of V1, activation enhancement during non-rapid-eye-movement sleep after training was observed specifically in the trained region of V1. Furthermore, improvement of task performance measured subsequently to the post-training sleep session was significantly correlated with the amount of the trained-region-specific fMRI activation in V1 during sleep. These results suggest that as far as V1 is concerned, only the trained region is involved in improving task performance after sleep