Gender-Related Clinical Differences in Obsessive-Compulsive Disorder

Objective：Some reports have shown the gender-related clinical differences in Obsessive-compulsive disorder (OCD), but no study has yet been done in Korea. The purpose of this study was to investigate the gender-related differences of clinical features in the obsessive-compulsive patients in Korea. Methods：Two hundred forty nine patients with OCD were included in this study；180 subjects were male and 69 subjects were female. The two groups were analyzed in terms of demographic data including clinical variable, Y-BOCS (Yale-Brown Obsessive Compulsive Scale) scores, clinical course and treatment response. Results：We found the earlier age at onset of OC symptoms in males and the more frequent washing and somatization type in female. There were no gender difference in comorbidity, clinical course and the treatment response. Conclusion：We could observe some of the gender-related clinical differences in Korean OCD patients. The further studies would be required to evaluate the gender difference in the long-term clinical course and therapeutic response of Korean OCD patients.ope

정신분열병환자에서 mismatch negativity와 얼굴정서인식의 관계

Dept. of Medicine/박사Background: Mismatch negativity (MMN) is an event-related potential that is closely related with the psychopathology of schizophrenia. Recently, MMN has been reported to be associated with social perception, a domain of social cognition. Social cognition is crucial for predicting social functioning in patients with schizophrenia. Facial emotion recognition is an important domain of social cognition. In the present study, facial emotion recognition and MMN were examined, and the relationship between them was explored in patients with schizophrenia vs. control subjects. Methods: Twenty patients with schizophrenia and 19 control subjects participated. The facial emotion recognition test consisted of a baseline condition, happy background condition, and fear background condition. In the background conditions, target facial stimuli were presented on happy or fear background faces. In the baseline condition, target faces were presented on a blank screen. Including both background and baseline conditions can provide information about the interaction between emotions. Sensitivity (d-prime) was calculated, and reaction time was measured. To make attention allocated to auditory stimuli different, the following 3 MMN conditions were employed: video condition, continuous performance test condition, and auditory target detection condition. Amplitude and latency were measured. The correlations between MMN and facial emotion recognition were analyzed.Results: Facial emotion recognition was more influenced by background emotion in patients with schizophrenia. Interactions between emotions were found and were different between groups. A subtle influence of attention on MMN was found in both groups. Different MMN waveforms were obtained, depending on deviant type and attention. Unlike control subjects, patients with schizophrenia showed significant correlations between MMN to duration deviant in the video condition and d-prime for fear target in the fear background condition, between MMN to duration deviant in the CPT condition and d-primes for neutral and fear targets in the fear background condition, and between MMN to white noise deviant in the CPT condition and d-prime for happy target in the happy background condition. Conclusion: This study addressed the relationship between MMN and facial emotion recognition. The association between MMN and social perception, a domain of social cognition, was previously reported. The present study extended those findings to the relationship with facial emotion recognition, another domain of social cognition. These findings suggest that deficits in early perceptual processing may have downstream consequences on higher-order social cognition.prohibitio

EFFECT OF LOADING DIRECTION ON THE LOW CYCLE FATIGUE BEHAVIOR OF ROLLED AZ31 MG ALLOY

Maste

학급자치법정에서 학급집단응집성이 또래압력에 미치는 영향

OAIID:oai:osos.snu.ac.kr:snu2015-01/102/0000025847/1ADJUST_YN:NEMP_ID:A075597DEPT_CD:711CITE_RATE:0DEPT_NM:사회교육과EMAIL:[email protected]_YN:NCONFIRM:

(The) effects of emotion on sustained attention in patients with schizophrenia

의학과/석사[한글] 정신분열병의 핵심 인지기능인 지속적 주의력에 정서가 영향을 미치는지에 대해 알아보고자 하였다. 21명의 정상대조군과 19명의 정신분열병 환자를 대상으로 정서사진을 배경으로 한 AX형 연속수행검사(Continuous performance test; CPT)를 수행하도록 하였다. 배경 정서 사진은 표준 표정정서사진에서 기쁨, 중립, 슬픔을 표현한 동일 모델의 사진을 사용하여, 기쁨, 중립, 및 슬픔 정서블록을 구성하였다. 시간 경과에 따른 지속적 주의력 저하 및 정신분열병 환자에서의 지속적 주의력 저하는 유의한 반면, 정서범주에 따른 지속적 주의력의 저하는 유의하지 않았다. 시간경과에 따른 지속적 주의력의 저하는 기쁨, 중립, 슬픔의 순으로 정서범주에 따라 서로 다른 경향을 보였다. 정상대조군에 비해 정신분열병 환자에서 시간이 경과함에 따라 지속적 주의력의 수행 정도가 현저하게 감소하였다. 정신분열병 환자에서 시간 경과에 따른 지속적 주의력의 저하는 정서범주별로 정상대조군과 서로 다른 양상이 관찰되지는 않았다. 이 소견들은 우선, 정신분열병 환자에서 지속적 주의력이 저하되었음을 재검하며, 둘째, 시간 경과에 따른 지속적 주의력 저하가 정서 범주에 따라 서로 다른 영향을 받을 가능성을 시사한다. 마지막으로 정서가 시간경과에 따른 지속적 주의력에 미치는 영향이 정신분열병에서 더 현저한 소견이 관찰되지 않은 것에 대해 토론하였다. [영문]The study was designed to find out the effects of emotion on sustained attention, which is crucial to schizophrenia. Continuous performance test with facial affect pictures as its background was applied to 21 controls and 19 schizophrenic patients. Happy, neutral and sad facial affect pictures of the same models were chosen among standard facial affect pictures, and happy, neutral and sad blocks were constructed. While sustained attention decrement by time and sustained attention decrement in schizophrenic patients were significant, sustained attention decrement according to emotional categories was not significant. The time-dependent decrement of sustained attention was observed in order of sad, neutral and happy emotional categories, with happy emotional category showing the largest decrement. The decrement by time was larger in schizophrenic group than control. The patient group did not show significant difference from control group in decrement patterns by time and by emotional categories. These findings confirmed the sustained attention deficit in schizophrenic group, and showed the possibilities of different effects on sustained attention decrement by time according to emotional categories. Finally this study showed that the sustained attention decrement pattern by time according to emotional categories did not show significant differences between control and patient group.restrictio

Deformation and low-cycle fatigue behaviors of rolled AZ31 Mg alloy: Influence of {10-12} twinning characteristics

DoctorMagnesium (Mg) alloys have recently attracted a great deal of research interest because of their potential applications for lightweight structural components. However, their applications are restricted because they exhibit a high directional anisotropy and are hard to deform at room temperature due to their limited number of deformation modes. In this regard, deformation twinning plays an important role in the deformation of Mg alloys by helping to satisfy the von Mises criterion, which requires five independent deformation systems for homogeneous deformation. Although several types of deformation twins have been reported for Mg alloys, the {10-12} twin is recognized to occur most easily and frequently. The {10-12} twinning can be active under two loading conditions (i.e., two activation modes)compression perpendicular to the c-axis of the hexagonal close-packed (HCP) lattice or tension parallel to the c-axis. The role of {10-12} twinning in the deformation can be understood by considering following three factors: (1) accommodation of plastic deformation, causing a low flow stress and strain hardening rate(2) Hall-Petch hardening by twinning-induced grain size change(3) twin texture induced change in activities of slips. Furthermore, such effects of {10-12} twinning on the deformation behavior would influence the fatigue properties of the material, which are considered a key factor for securing the reliability of products. In this study, the differences in {10-12} twinning characteristics between two activation modes (compression perpendicular to the c-axis and tension parallel to the c-axis) and their effects on the deformation characteristics (flow stress and strain hardening) were investigated using a rolled AZ31 Mg alloy. Moreover, the effects of material variables, such as stress/strain ratio, loading direction, and initial {10-12} twin, on the low-cycle fatigue behavior were also investigated.The results revealed that the active twin variants during {10-12} twinning are dependent on the activation mode and their section mechanism is governed by the Schmid lawalthough the nucleation of {10-12} twins was governed by the Schmid law, their growth characteristics during further deformation were significantly dependent on the activation mode, causing a totally different twinning contribution to the deformation. The intersection between different twin variant pairs was found to retard the twin growth and promote the nucleation of new twins.The activation of specific twin variants depending on the activation mode induced a significant difference in twinning characteristics, such as twin morphology, volume fraction of twins with strain, and twin texture, and consequently gave rise to a totally different effect on the deformation. The differences in the deformation characteristics (flow stress and strain hardening) between both activation modes were successfully explained in relation with activation stresses for twinning and slips, activities of twinning and slips in the deformation, Hall-Petch effect by twinning-induced grain size change, and twinning-induced change in activities of slips.Fatigue characteristics were investigated by performing the low-cycle fatigue (LCF) tests under various stress/strain conditions along the rolling direction (RD). The alloy was found to have a strong basal texture so that the fatigue deformation was dominated by the alternation of {10-12} twinning and detwinning during each cycle, and this made the cyclic stress response unstable and introduced a mean stress and/or strain depending on the loading condition. The effect of loading direction on the fatigue resistance was also examined by conducting the LCF tests along the normal direction (ND) to the rolling plane and comparing the results with those of the RD. Because of the intense basal texture, which facilitates the generation of {10-12} twinning under two loading conditions mentioned above, the material yielded easily in compression along the RD, while it was easy to yield in tension along the ND. Such a plastic anisotropy caused a superior fatigue resistance along the ND by introducing a beneficial compressive mean stress. In addition, the improvement of the fatigue resistance was achieved by reducing the tensile mean stress developed during fatigue deformation, which was available by tailoring the {10-12} twinning-detwinning characteristics of the material through the pre-compression process. The modification of the {10-12} twinning-detwinning characteristics made it possible to control the plastic deformation mechanisms activated during fatigue deformation so that the imposed tensile strain could be fully accommodated by the detwinning alone and this led to a significant reduction of tensile flow stress, finally resulting in the reduction of mean stress