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Substantial enhancement of terahertz magnetic near field achieved by the combination of a tapered metallic waveguide and a micro-split-ring resonator is demonstrated. The magnetic near field is probed directly via the magneto-optic sampling with a Tb 3 Ga 5 O 12 crystal. The incident terahertz wave with a half-cycle waveform is generated by using the pulse-front tilting method. The magnetic near field at the resonant frequency is enhanced by more than 30 times through the combination of the waveguide and the resonator. The peak amplitude of the magnetic field with a damped oscillation waveform in the time domain is up to 0.4 T. The resonant frequency can be tuned by adopting different resonator designs. The mechanism of the enhancement is analyzed by performing calculations based on the finite element method. The strong terahertz magnetic near field enables the excitation of large-amplitude spin dynamics and can be utilized for an ultrafast spin control.

With rapid advances occurring in terahertz (THz) radiation generation techniques, the interaction between matter and intense THz fields has become an important research topic. Among different types of THz radiation sources, the free electron laser (FEL) is a promising experimental tool that is expected to pave the way for new forms of material processing, control of phase transitions, and serve as a test bench for extreme operating conditions in high-speed small-size electrical and magnetic devices through the exploitation of strong THz electrical and magnetic fields without the presence of interband electronic excitation. In the current work, we irradiated Ge 2 Sb 2 Te 5 phase change memory material with intense THz pulse trains from an FEL and observed THz-induced surface changes due to damage as a precursor to ablation and the formation of fine surface undulations whose spatial period is comparable to or slightly smaller than the wavelength of the excitation THz pulses in the material. The formation of undulations as well as the fact that no significant thermal effect was observed below the volume expansion threshold suggests that THz-induced effects mainly contributed to the observed changes. To the best of our knowledge, this is the first experimental observation of THz-induced undulations (so-called "LIPSS"), which are of potential importance for laser material processing.

Reduced specificity of autobiographical memories is a hallmark of depressive cognition. Autobiographical memory (AM) specificity is typically measured by the Autobiographical Memory Test (AMT), in which respondents are asked to describe personal memories in response to emotional cue words. Due to this free descriptive responding format, the AMT relies on experts' hand scoring for subsequent statistical analyses. This manual coding potentially impedes research activities in big data analytics such as large epidemiological studies. Here, we propose computerized algorithms to automatically score AM specificity for the Dutch (adult participants) and English (youth participants) versions of the AMT by using natural language processing and machine learning techniques. The algorithms showed reliable performances in discriminating specific and nonspecific (e.g., overgeneralized) autobiographical memories in independent testing data sets (area under the receiver operating characteristic curve > .90). Furthermore, outcome values of the algorithms (i.e., decision values of support vector machines) showed a gradient across similar (e.g., specific and extended memories) and different (e.g., specific memory and semantic associates) categories of AMT responses, suggesting that, for both adults and youth, the algorithms well capture the extent to which a memory has features of specific memories. (PsycINFO Database Record, ((c) 2018 APA, all rights reserved).)

Biased information processing has been highlighted as a possible vulnerability factor for sleep problems. A theory states that perceived sleeplessness triggers a strong approach motivation (or craving) for sleep, and then activates persistent preoccupation with sleep. However, there is no clear evidence that perceived sleeplessness is associated with such a motivation toward sleep-related information. Thus, we examined the untested idea that people with subjective sleep disturbances would prefer sleep-related topics, using a modified version of the pay-per-view task. In this task, 58 participants were offered two question-type options: the "sleep" option, where participants were asked to answer a question about their sleep, and the "eat" option, where participants needed to answer a question about their eating habits and beliefs. Each option is associated with a variable amount of economic reward and therefore participants sometimes face a conflict between the economic reward and their intrinsic preference for a specific question type. Results showed that people with higher levels of subjective sleep disturbances forgo greater amounts of reward to have an opportunity to answer sleep-related (as opposed to than eating-related) questions. These findings suggest that people who perceive themselves as lacking sleep are highly motivated to engage in sleep-related information processing., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Learning theories of depression have proposed that depressive cognitions, such as negative thoughts with reference to oneself, can develop through a reinforcement learning mechanism. This negative self-reference is considered to be positively reinforced by rewarding experiences such as genuine support from others after negative self-disclosure, and negatively reinforced by avoidance of potential aversive situations. The learning account additionally predicts that negative self-reference would be maintained by an inability to adjust one's behavior when negative self-reference no longer leads to such reward. To test this prediction, we designed an adapted version of the reversal-learning task. In this task, participants were reinforced to choose and engage in either negative or positive self-reference by probabilistic economic reward and punishment. Although participants were initially trained to choose negative self-reference, the stimulus-reward contingencies were reversed to prompt a shift toward positive self-reference (Study 1) and a further shift toward negative self-reference (Study 2). Model-based computational analyses showed that depressive symptoms were associated with a low learning rate of negative self-reference, indicating a high level of reward expectancy for negative self-reference even after the contingency reversal. Furthermore, the difficulty in updating outcome predictions of negative self-reference was significantly associated with the extent to which one possesses negative self-images. These results suggest that difficulty in adjusting action-outcome estimates for negative self-reference increases the chance to be faced with negative aspects of self, which may result in depressive symptoms.

Studies on autobiographical memory retrieval highlight the prominence of rapid and direct access to a specific event memory. Because it has been believed that autobiographical memory retrieval mostly relies on an effortful generative process, there is little empirical evidence on the early stage of information processing that contributes to autobiographical memory specificity (AMS). Therefore, we investigated the associations between AMS and automatic activation of information stimulated by rapid presentation of emotional words. Study 1 involved a visual search task to assess activation of various distractors in working memory. Participants with reduced AMS showed a tendency to activate distractors that were not semantically associated with preceding cues. In Study 2, we manipulated the levels of AMS by using a computerized version of Memory Specificity Training (c-MeST) to observe the changes in the activation of distractors. Results showed that increases in AMS were associated with decreases in activation of cue-unassociated distractors. These findings suggest that reduced AMS can be characterized by dispersed activation spreading over semantically unassociated distractors in automatic information selection of working memory. Because we also found an association between depressive symptoms and AMS, the role of automatic information processing in the relation between reduced AMS and depression is discussed., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In the present study, we explored the linguistic nature of specific memories generated with the Autobiographical Memory Test (AMT) by developing a computerized classifier that distinguishes between specific and nonspecific memories. The AMT is regarded as one of the most important assessment tools to study memory dysfunctions (e.g., difficulty recalling the specific details of memories) in psychopathology. In Study 1, we utilized the Japanese corpus data of 12,400 cue-recalled memories tagged with observer-rated specificity. We extracted linguistic features of particular relevance to memory specificity, such as past tense, negation, and adverbial words and phrases pertaining to time and location. On the basis of these features, a support vector machine (SVM) was trained to classify the memories into specific and nonspecific categories, which achieved an area under the curve (AUC) of .92 in a performance test. In Study 2, the trained SVM was tested in terms of its robustness in classifying novel memories (n = 8,478) that were retrieved in response to cue words that were different from those used in Study 1. The SVM showed an AUC of .89 in classifying the new memories. In Study 3, we extended the binary SVM to a five-class classification of the AMT, which achieved 64%-65% classification accuracy, against the chance level (20%) in the performance tests. Our data suggest that memory specificity can be identified with a relatively small number of words, capturing the universal linguistic features of memory specificity across memories in diverse contents.

Purpose: Adolescent and young adult cancer (AYAC) survivors show an elevated risk of distress. Targeted psychosocial interventions for this distinct population are needed. This study examined the potential efficacy of a mindfulness-based intervention (MBI) to alleviate emotional distress and improve quality of life (QoL) in AYAC survivors., Methods: Participants were 16 AYAC survivors, aged 14-24, who had completed acute medical treatment. A two-baseline (8 and 1 week before the intervention), post- (1 week after the intervention) and 3 months follow-up within-subjects design was used. Each participant completed two baseline assessments, followed by an 8-week MBI. The primary outcome variables were emotional distress and QoL. Secondary outcomes were cognitive vulnerability factors and mindfulness skills., Results: Multilevel modeling showed (1) a significant reduction in emotional distress and improvement in QoL at 3 months of follow-up, (2) a significant reduction in negative attitudes toward self (i.e., a cognitive vulnerability factor), and (3) a significant improvement in mindfulness skills., Conclusion: MBI is a promising approach that is used to treat emotional distress and to improve QoL in AYAC survivors. Further research using randomized controlled trials is needed to generalize these findings. Trial registration information: www.trialregister.nl ; NTR4358.

Maladaptive forms of self-focus, such as rumination, are considered transdiagnostic factors that contribute to depressive and anxiety symptoms. However, no or few studies have explored the possibility that adaptive forms of self-focus can also be a common factor that is negatively associated with depressive and anxiety symptoms. To test this possibility, we first examined the psychometric properties of a scale measuring adaptive forms of self-focus (the Self-Reflection and Insight Scale) on Japanese undergraduates (n=117). We replicated the two-factor structure of the scale: (a) self-reflection, which is a tendency to focus purposefully on self for self-regulation, and (b) insight, which is a sense of clear self-understanding. Second, we tested our specific hypothesis that these two factors negatively predict a common factor of depressive and anxiety symptoms. The results of structural equation modeling showed that insight (but not self-reflection) has a significant negative association with a latent variable that explains both depressive and anxiety symptoms. Furthermore, this common-factor model explained the data better than a control model in which insight predicts depressive and anxiety symptoms individually. These results suggest that (lack of) insight plays an important role in psychological (mal)adjustment as a shared process in depressive and anxiety symptoms., (Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.)

The autobiographical memory test (AMT) is a widely used measure to assess the specificity of autobiographical memories. Reduced Autobiographical Memory Specificity (AMS) or increased overgeneralization of memories is considered as a cognitive hallmark of depression. Therefore, reduced AMS is the subject of much psychopathological research, and is a promising target for psychological interventions. Although considerable evidence has been gathered on the clinical relevance of reduced AMS over the past decades, studies on AMS have been mainly conducted in Western populations, and few have been conducted in Asian populations. This could be because of the unknown psychometric properties of the AMT given cultural and language differences. Therefore, the present study examined the psychometric properties of the AMT in a Japanese community sample (N=1240). Our data replicated that (a) the AMT has a uni-factorial structure; (b) AMS has a small but statistically significant negative correlation with depressive symptoms; (c) AMS shows a significant declining trend as a function of age, which influences the magnitude of the association between AMS and depressive symptoms in older adults. These findings suggest that the AMT has robust psychometric properties across different languages and cultural backgrounds., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

The self-positivity bias, which is inherent to healthy people, is known to be blunted in depression. The lack of positive or excessive negative self-reference is considered to be a potential mechanism underlying depressive rumination. However, the motivational factors that drive people to approach and avoid emotional self-related materials are still unclear. Therefore, we measured intrinsic motivation that is associated with emotional self-references by using a reward-based decision-making task (pay-per-view paradigm). Forty-nine undergraduates completed two tasks in which they were asked to choose between negative vs. positive references (Task 1) and self vs. other references (Task 2) for variable monetary rewards. Participants with lower levels of depressive symptoms showed a self-positivity bias, sacrificing rewards for the opportunity to engage in positive self-reference, whereas those with higher levels of depressive symptoms had no specific preference for either negative or positive self-reference (Task 1). However, all participants sacrificed monetary rewards for the opportunity for self-reference versus other reference, regardless of the symptom level or the primed valence (Task 2). Together, these findings suggest that depressive cognition could be characterised by the lack of intrinsic motivation for positive self-reference, which is attributable to the biased valence selection, but not to self-other preferences.

We proposed and demonstrated terahertz (THz) pulse detection by means of multilayered GeTe/Sb 2 Te 3 phase-change memory materials that are also known as a multilayer topological insulator-normal insulator (MTN) system. THz time-domain spectroscopy measurement was performed for MTN films with different multilayer repetitions as well as a conventional as-grown Ge-Te-Sb (GST) alloy film. It was found that MTNs absorb THz waves and that the absorption coefficient depends on the number of layers, while the as-grown GST alloy film was almost transparent for THz waves. Simple MTN-based THz detection devices were fabricated, and the THz-induced change in the current signal was measured when a DC bias voltage was applied between the electrodes. We confirmed that irradiation of THz pulse causes a decrease in the resistance of the MTNs. This result indicates that our devices are capable of THz detection.

Background and Objectives: Misperception of sleep (e.g., underestimation of sleep time relative to objective measures) is a common feature of insomnia and other psychopathologies. To elucidate the mechanisms underlying this tendency, we examined the role of pre-sleep cognitive arousal and overgeneralization., Methods: We monitored the sleep of 54 community dwellers (the majority being university students), using actigraphy and a sleep diary for 7 days. Immediately after this period, the participants provided an additional global evaluation of their sleep for the past week. In this global evaluation, participants were asked to estimate their average number of hours of sleep and the duration of time taken to fall asleep (sleep onset latency) across the past seven nights., Results: Single-night misperceptions (difference between actigraphy and sleep diary estimations) of sleep time and sleep onset latency were significantly associated with pre-sleep cognitive arousal, but not with overgeneralization. In contrast, global misperception of sleep (difference between sleep diary and global estimations) were associated with overgeneralization, but not with cognitive arousal., Limitations: Our sample mainly consisted of female university students, which limits the generalizability of the results., Conclusions: Misperception of sleep occurs in two cases: (1) in the case of a single night due to excessive arousal, and (2) in the case of multiple nights due to overgeneralization., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The purpose of this study was to examine how university social capital and subjective social capital could predict undergraduate students’ subjective well-being including depression, school satisfaction, and life satisfaction. In this cross-sectional study, we conducted multilevel structural equation modeling on the data of 2,021 students at 38 universities in Japan. At the university level, we found the associations between social capital (fellows) and depression, social capital (classmates) and life satisfaction, and social capital (faculty) and school satisfaction. At the student level, all subjective social capital (fellows, classmates, and faculty) were associated with all the factors of subjective well-being. These results suggest the influence of university social capital and that of subjective social capital are associated with students’ subjective well-being.

Previous studies have shown a negative correlation between effortful control (EC) and depressive symptoms. EC is defined as the efficiency of executive attention, which may be reduced by the attentional impairment associated with depression. However, the mechanism underlying this correlation is still unclear. We investigated the relationship between EC and depressive symptoms with the hypothesis that cognitive motivation, or need for cognition (NfC), is a possible mediator of this relationship. Participants were 178 Japanese university students. Each completed the Zung Self-Rating Depression Scale, Effortful Control Scale, and Need for Cognition Scale at baseline and follow-up assessments. Supporting our hypothesis, mediation analyses revealed a significant indirect effect of depressive symptoms on EC that was mediated by NfC. In addition, our data demonstrated a direct effect of depressive symptoms on EC. Longitudinal analysis indicated that an increase in depression and a decrease in NfC occurred synchronously, while NfC predicted an increase in EC over time. Depressive symptoms may decrease executive functioning and effortful control both directly and indirectly, the latter effect being mediated by motivation. These findings imply that a motivational deficit may partially explain the decreased EC found in people suffering from depression., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

We demonstrate terahertz pulse generation from silver nanoparticle ink, originally developed for printed electronics, under irradiation by femtosecond laser pulses. Using metal nanoparticle ink, metallic nanostructures can be easily made in a large area without lithographic techniques. Terahertz pulses were emitted from the baked ink, having spontaneously formed nanostructures of ∼100  nm. From the results of the baking temperature dependence and the polarization measurement, the terahertz generation is attributed to the nonlinear polarization induced by the enhanced local fields around these nanostructures. This study paves the way for the future development of terahertz emitters which have resonances in both the near-infrared light and the terahertz wave, by combining micrometer-scale structures drawn by an inkjet printer and nanometer-scale structures formed during the baking process.

Previous studies have shown that attentional bias modification (ABM) is effective in reducing negative attentional biases. However, the mechanisms underlying how ABM effectively reduces negative attentional biases are still unclear. In the present study, we conducted an ABM procedure that included a 3-day training session with a sample of nonclinical participants (N = 40) to investigate the effect of ABM on emotional and nonemotional attentional biases. Participants completed a modified dot-probe task with 2 different instructions (explicit or standard) during the training; their attentional biases were tested before and after the training. Only participants trained with explicit instructions showed a reduction in negative attentional biases in dot-probe task and an improvement in attentional disengagement from negative stimuli in gap-overlap task. On the other hand, attention toward nonemotional stimuli was only marginally improved by training with both explicit and standard instructions. These results indicate that explicit instructions may promote ABM training., ((c) 2015 APA, all rights reserved).)

We demonstrate a sensor card with cholesteric liquid crystals (CLCs) for terahertz (THz) waves generated from a nonlinear crystal pumped by a table-top laser. A beam profile of the THz waves is successfully visualized as color change by the sensor card without additional electronic devices, power supplies, and connecting cables. Above the power density of 4.3  mW/cm2, the approximate beam diameter of the THz waves is measured using the hue image that is digitalized from the picture of the sensor card. The sensor card is low in cost, portable, and suitable for various situations such as THz imaging and alignment of THz systems.

We tested the usefulness of name-letter preference scores as indirect indicators of self-esteem by exploring whether multiple unsupervised self-administrations of letter rating tasks within a short period of time yield useful data. We also examined whether preferences for initials and noninitial name-letters tap different aspects of self-esteem. Participants from a community sample (N = 164; 58 men and 106 women, 17-67 years, Mage = 34.57, SD = 13.28) completed daily letter rating tasks and state self-esteem questionnaires for 7 consecutive days. They also completed a trait self-esteem questionnaire on the first measurement day as well as 6 months later. Preference scores for first-name initials were stronger but more unstable than preference scores for other name-letters. Preferences for first-name initials were primarily associated with directly measured state self-esteem whereas preferences for noninitials were primarily associated with directly measured trait self-esteem even if the latter was measured 6 months later. Thus, we showed that preferences for initials and noninitials are not simply interchangeable. Previous letter rating studies, which almost exclusively used initial preferences, should be interpreted in terms of state rather than trait self-esteem. In future studies, researchers should focus on the name-letter preference that reflects the aspect of self-esteem they wish to address., ((c) 2015 APA, all rights reserved.)

Quasi-monodisperse dielectric particles organized in a periodic hexagonal network on an aluminum surface are exploited numerically and experimentally as a single-layered near-perfect absorber in the terahertz regime. Of particular interest are titanium dioxide (TiO(2)) microspheres because of their large dielectric permittivity and isotropic shape leading to Mie resonances with insensitive polarization. Absorption higher than 80% at normal incidence covering two distinct ranges of frequencies is demonstrated experimentally. Furthermore, the performance of the metamaterial absorber is kept over a wide range of incident angles.

Background and Objectives: Females are more likely to engage in the preoccupation of past negative experiences than males, which might contribute to their greater tendency toward depression. However, there is limited understanding regarding the cognitive basis for the negative autobiographical information processing of females. In the present study, we assessed the cognitive resources required for negative thinking, by using a novel dual-task paradigm that combined think-aloud and time-estimation tasks., Methods: Fifty-three Japanese undergraduate students were asked to think aloud about personal past or future emotional episodes for a particular duration. In addition, they were asked to estimate the duration of their speech. Their estimates were compared to the actual time taken, and the errors were used as indices of cognitive burden during the speech task., Results: As compared to males, females exhibited greater judgment errors, particularly when thinking about their past negative experiences. This suggests that females allocate more attentional resources toward thinking about the past., Limitations: Participants could rehearse the task during the time reproduction phase, and the quality of the rehearsal and their memory capacity might have influenced the accuracy of their duration judgment., Conclusions: Females tend to allocate more attentional resources than males to thinking about past negative episodes, which in turn might be associated with reduced availability of resources for central cognitive control processes such as inhibition of and switching away from processing of negative autobiographical information., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Transmission spectra of near-self-complementary metallic checkerboard patterns (MCPs) exhibit a drastic change when the metal squares are brought into contact with each other from a noncontact state. Transmission spectra of near-self-complementary samples, which are fabricated by printing technology, show rather gradual systematic change with changing the nominal metal square size while keeping the period because of randomness naturally introduced by the limited accuracy of the printer. The spectra have transmission-invariant frequencies, which means that the spectra are a superposition of two types of spectra, the ratio of which depends on the nominal square size. The correlation seen in the real and imaginary parts of the complex amplitude spectra can be interpreted based on the Kramers-Kronig relation. As an application of the sensitiveness of the transmission spectrum of the MCPs to connectivity of the metal squares, the revealing of an optically hidden pattern by a terahertz beam is demonstrated.

Microstructures in nature are ultrafine and ordered in biological roles, which have attracted material scientists. Spirulina forms three-dimensional helical microstructure, one of remarkable features in nature beyond our current processing technology such as lithography in terms of mass-productivity and structural multiplicity. Spirulina varies its diameter, helical pitch, and/or length against growing environment. This unique helix is suggestive of a tiny electromagnetic coil, if composed of electro-conductive metal, which brought us main concept of this work. Here, we describe the biotemplating process onto Spirulina surface to fabricate metal microcoils. Structural parameters of the microcoil can be controlled by the cultivation conditions of Spirulina template and also purely one-handed microcoil can be fabricated. A microcoil dispersion sheet exhibited optically active response attributed to structural resonance in terahertz-wave region.

Excessive focus on the internal self has maladaptive consequences for mental and physical health. Although the emotional functions of self-focus have been well established, no study has examined physiological arousal during the daily experience of self-focused thinking. The present study investigates the association between self-focus and autonomic activity using the experience sampling method with ambulatory monitoring of heart rate variability (HRV). Forty-five students reported the content of their thoughts during their daily activities while their heart rate (HR) was being recorded. Multilevel modeling analyses showed that HRV was lower (and HR was higher) over the sampling day if participants engaged in more self-focus, while HRV increased (and HR decreased) from midday to nighttime if participants did not engage in self-focused thinking. These results suggest that self-focus at night is associated with increased physiological arousal, and leads to inhibition of de-arousal associated with normal sleep processes. Implications for insomnia are discussed., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Although previous research has suggested that presleep negative cognitive activities are associated with poor sleep quality, there is little evidence regarding the association between negative thoughts and sleep in real-life settings. The present study used experience sampling and long-term sleep monitoring with actigraphy to investigate the relationships among negative repetitive thought, mood, and sleep problems. During a 1-week sampling period, 43 undergraduate students recorded their thought content and mood eight times a day at semirandom intervals. In addition to these subjective reports, participants wore actigraphs on their wrists in order to measure sleep parameters. Analyses using multilevel modeling showed that repetitive thought in the evening was significantly associated with longer sleep-onset latency, decreased sleep efficiency, and reduced total sleep time. Furthermore, impaired sleep quality was significantly associated with reduced positive affect the next morning, and decreased positive affect was indirectly associated with increased repetitive thought in the evening. These findings suggest the existence of a self-reinforcing cycle involving repetitive thought, mood, and impaired sleep quality, highlighting the importance of cognitive and emotional factors in enhancement and maintenance of good-quality sleep., (© 2013.)

Terahertz (THz) transmission modulation through copper phthalocyanine (CuPc)-coated Si under various laser light irradiation conditions was investigated using THz time-domain spectroscopy. The charge carrier transfer from Si to CuPc is crucial for photo-induced metallization, and the thickness of the CuPc layer is a critical parameter for achieving high charge carrier density for metallization. Transmission through a split-ring resonator array metamaterial, fabricated on CuPc-coated Si, can be efficiently modulated by laser light irradiation. Our findings may open the way for various types of metamaterials using organic conjugated materials that are suitable for easy device fabrication using printing technologies.

The present study examined the situations and conditions in which ruminative self-focus is less likely to occur in daily life. Previous researchers have described a mood-brightening effect of depression, where depressed individuals exhibit greater positive emotional reactivity to positive daily events than do nondepressed individuals. To better understand this paradoxical effect, we investigated the moderating role of depression in the relationship between daily activities and ruminative thinking. Forty-one Japanese undergraduates (9 women and 32 men) recorded their thought contents and the type and subjective appraisals of activities that they engaged in 8 times a day for a week at semirandom intervals. Multilevel modeling analyses indicated that subjectively pleasant activities were associated with improved mood states and reduced ruminative thinking. However, some of these associations were moderated by depressive symptoms, suggesting that individuals with higher levels of depression showed a greater reduction of ruminative thinking during pleasant activities. These results imply that daily activities are important for reducing rumination, particularly for individuals with higher levels of depression, and that the brightening effect of depression is evident for cognitive as well as emotional activities. The cognitive basis of this paradoxical effect is discussed., (PsycINFO Database Record (c) 2013 APA, all rights reserved.)

Repetitive thought has been focused upon as a transdiagnostic risk factor for depression, anxiety, and poor physical health. Among the forms of repetitive thought, rumination and worry are considered to play important roles in the onset and maintenance of insomnia. However, there have been few attempts to clarify the similarities, differences, and interaction between the functions of rumination and worry in sleep problems. Furthermore, no study has investigated the prospective relationships between these two forms of repetitive thought and sleep disturbance. In the present study, we examined the prospective associations between repetitive thought and subjective sleep quality, measured by a self-report questionnaire. A total of 208 undergraduates participated in a 2-wave longitudinal survey with an interval of 3weeks between assessments. Hierarchical multiple regression analyses showed that baseline rumination predicted reduction in the follow-up assessment of subjective sleep quality, controlling for levels of depressive and anxious symptoms. This main effect of rumination was qualified by the levels of worry; for individuals with higher levels of worry, rumination was associated with greater reduction in subjective sleep quality. These results suggest that both rumination and worry have unique associations with sleep and that their interaction is especially important in sleep problems., (Copyright © 2012. Published by Elsevier Ltd.)

The present study investigated the daily fluctuation of ruminative thinking and its individual differences by using the experience sampling method. Participants recorded their thought contents and negative affect eight times a day for a week at semirandom intervals. High-trait ruminators showed high levels of self-focus, unpleasantness, and uncontrollability in their thoughts over the sampling course. These variables were interacted to predict the levels of concurrent negative affect: Self-focus was strongly associated with increased levels of negative affect when the thought was highly unpleasant and uncontrollable. A composite measure of rumination, including self-focus, unpleasantness, and uncontrollability, exhibited diurnal variation, which was assimilated by a quadratic function of time of day. However, there were differences in the estimated parameters of diurnal trajectories between high and low levels of depression, which indicated that individuals with higher levels of depression are more likely to engage in rumination in the evening, not in the morning, than those with lower levels of depression. These findings suggest that rumination in the evening would play an important role in the exacerbation and maintenance of depression.

Wire-grid polarizer sheets in the terahertz region have been fabricated on flexible substrates by nanoimprint technology. They show an ideal polarization property in the terahertz frequency region, whereas the cost is very low. Since the wire pitch is far smaller than the wavelength, the effective medium theory agrees well with experimental results. The effective medium theory shows the possibility of further improvement of polarization properties by selecting appropriate materials for wire grids., (© 2011 Optical Society of America)

We theoretically predicted the existence of an anomalous optical transmittance dip, which must be observed for a metamaterial structure with two metallic slabs with cut-through slit arrays of a constant period d under a normal incident condition. By changing the relative lateral displacement l between the two slabs, the dip frequency varies across that of a so-called Rayleigh-Wood's (RW) anomaly frequency. The mechanism of this anomaly is quite different from that of the RW anomaly and interpreted in terms of the interference between the propagating and evanescent waves. For the present double-layered system, furthermore, it is suggested that the RW anomaly vanishes for l = 0 and d/2. In experiments in the terahertz region, we observe that the fundamental features agree with these theoretical predictions.

We investigate characteristics and generation process of surface waves excited on a structured perfect conductor surface in order to clarify the mechanism of resonant transmission in metal hole arrays made of the perfect conductor. By using a metal hole array of kagome lattice, we can separate two modes excited on the perfect conductor surface; a surface wave and an edge mode. Our calculation based on finite-difference time-domain method provides a generation process of the edge mode and the surface wave that is responsible for the resonant transmission in metal hole arrays.

The present study used the experience sampling method to detect fluctuations in thinking, such as self-focus or concreteness in daily life, and to examine their relationship with depressive symptoms and concurrent negative affect. Thirty-one undergraduates recorded their negative affect, ruminative self-focus, and concreteness of thinking eight times a day for 1 week. Multilevel modeling showed that individuals with increasing levels of depression showed lower levels of concreteness in their daily thinking. Further analysis revealed a significant positive association between momentary ruminative self-focus and concurrent negative affect only with low concreteness of thinking. These results suggested that individuals with increasing levels of depression chronically process self-related information on an abstract level, which reflects a malfunction of their self-regulatory cycle and might serve to maintain or even exacerbate dysphoric moods.

A "sense of agency" involves a contemporaneous experience that the "self" causes the actions performed by the "self" (i.e., "I am the one who causes my actions"). This may comprise the main component of self-consciousness. The present research focuses on the development of a questionnaire to investigate the subjective aspects of a sense of agency. We selected items from the extant relevant measures and from previous empirical studies, and conducted four longitudinal surveys with additional scales. Statistical computations confirmed the validity and reliability of the Sense of Agency Scale (SOAS), consisting of seventeen items involving three factors. Furthermore, the results indicated that these three factors might be organized hierarchically, with each factor showing a unique relationship with emotional or social traits. This novel finding, emerging from the Sense of Agency Scale, would have been difficult to obtain via traditional empirical studies.

The absorption spectra of ceftazidime and its generic versions (Modacin, Mosyl, and Mobenzocin) have been measured by terahertz time domain spectroscopy (THz-TDS). Differences in the THz absorption were observed between the original and generic versions. The results show small, but significant differences in the states of ceftazidime hydrate between the original and generic versions. THz-TDS can be used to evaluate the stability of medicines as well as to control their quality.

Self-focused attention has adaptive and maladaptive aspects: self-reflection and self-rumination [Trapnell, P. D., & Campbell, J. D. (1999). Private self-consciousness and the Five-Factor Model of personality: distinguishing rumination from reflection. Journal of Personality and Social Psychology, 76, 284-304]. Although reflection is thought to be associated with problem solving and the promotion of mental health, previous researches have shown that reflection does not always have an adaptive effect on depression. Authors have examined the causes behind this inconsistency by modeling the relationships among self-reflection, self-rumination, and depression. One hundred and eleven undergraduates (91 men and 20 women) participated in a two-time point assessment with a 3-week interval. Statistical analysis with structural equation modeling showed that self-reflection significantly predicted self-rumination, whereas self-rumination did not predict self-reflection. With regard to depression, self-reflection was associated with a lower level of depression; self-rumination, with a higher level of depression. The total effect of self-reflection on depression was almost zero. This result indicates that self-reflection per se has an adaptive effect, which is canceled out by the maladaptive effect of self-rumination, because reflectors are likely to ruminate and reflect simultaneously.

We fabricated a terahertz wire-grid polarizer consisting of a micrometer-pitch Al grating on a Si substrate by photolithography and wet etching. The ratio of TM and TE transmittances (extinction ratio) was over 35 dB at 0.5 THz. At the Brewster angle of the Si substrate, the polarization transmittance of a TM wave through the fabricated polarizer exceeded 95% and the extinction ratio was over 45 dB at approximately 1 THz. The fabricated polarizer has a higher extinction ratio than conventional free-standing terahertz wire-grid polarizers.

Absorption spectra of polycrystalline L-, D-, and DL-tartaric acid have been measured by terahertz time domain spectroscopy (THz-TDS). Different absorption bands are observed for DL-tartaric acid and its enantiomers (L- and D-tartaric acid). This result shows that the THz-TDS can be used for distinguishing between DL-tartaric acid and enantiomers (L- and D-tartaric acid). Moreover, partial least square (PLS) can be found to improve the quantitation of L-tartaric acid in L- and DL-tartaric acid mixture by THz-TDS.