Red cell manufacturing using parallel stirred-tank bioreactors at the final stages of differentiation enhances reticulocyte maturation.

The aim of this study was to develop a robust, quality controlled, and reproducible erythroid culture system to obtain high numbers of mature erythroblasts and red blood cells (RBCs). This was achieved using a fully controlled stirred-tank bioreactor by the design of experiments (DOE) methods in the serum-free medium by defining the appropriate culture parameters. Human cord blood CD34+ cells were first cultured in static flasks and then inoculated to stirred-tank bioreactors. Cell diameter was gradually decreased and final RBC yields were significantly higher when cells were inoculated at sizes smaller than 12 µm. The larger immature cells in the basophilic stage did not survive, while smaller mature erythroid cells were successfully expanded at high agitation speeds, demonstrating that appropriate seeding timing is critical. A high inoculation cell density of 5 × 106 cells/ml was achieved reaching 1.5 × 107 cells/ml. By using DOE analysis fitted to precise stages of erythropoiesis, we were able to acquire the optimal culture parameters for pH (7.5), temperature (37°C), dissolved oxygen, agitation speed (500 rpm), inoculation timing (cell diameter 12-13 µm), media feeding regimen, and cell seeding density (5 × 106 cells/ml). The final pure RBCs showed appropriate functions compared with fresh donor RBCs, confirming that manufacturing mature RBCs with reproducibility is possible.

The Effects of Long-Term Ketamine Treatment on Cognitive Function in Complex Regional Pain Syndrome: A Preliminary Study.

OBJECTIVE: This preliminary study aimed to investigate the effects of long-term frequent ketamine treatment on cognitive function in [AQ-A] CRPS patients. DESIGN: A total of 30 CRPS patients were divided into two groups based on both the duration and frequency of ketamine treatment; the long-term frequent ketamine treatment (LF) group (N = 14) and the Non-LF group (N = 16). Participants were asked to complete a questionnaire packet including demographic and clinical characteristics and potential variables affecting cognitive function. Then, they performed the neuropsychological test. RESULTS: Results indicated that the LF group performed significantly poorer than the Non-LF group on the digit span, digit symbol, Controlled Oral Word Association Test, and Trail Making Test, but not the Stroop task. CONCLUSIONS: Patients with CRPS receiving long-term frequent ketamine treatment showed impairment in cognitive function (specifically executive function) compared with those who do not. These findings may have implications for clinical assessment and rehabilitation of cognitive function in CRPS patients.

The influence of attention toward facial expressions on size perception.

According to the New Look theory, size perception is affected by emotional factors. Although previous studies have attempted to explain the effects of both emotion and motivation on size perception, they have failed to identify the underlying mechanisms. This study aimed to investigate the underlying mechanisms of size perception by applying attention toward facial expressions using the Ebbinghaus illusion as a measurement tool. The participants, female university students, were asked to judge the size of a target stimulus relative to the size of facial expressions (i.e., happy, angry, and neutral) surrounding the target. The results revealed that the participants perceived angry and neutral faces to be larger than happy faces. This finding indicates that individuals pay closer attention to neutral and angry faces than happy ones. These results suggest that the mechanisms underlying size perception involve cognitive processes that focus attention toward relevant stimuli and block out irrelevant stimuli.

Confirmatory factor analysis of the Korean version of the short-form McGill pain questionnaire with chronic pain patients: a comparison of alternative models.

BACKGROUND: The Short Form of the McGill Pain Questionnaire (SF-MPQ) is the most widely used assessment of the quality and intensity of pain. In previous validation studies, the factor structure of the SF-MPQ varied widely from various two-factor structures to a five-factor structure, although research on the SF-MPQ quite consistently supports its two-factor structure (i.e., sensory and affective) across different countries and languages. In Korea, the results of exploratory factor analysis of a Korea version of SF-MPQ (KSF-MPQ) showed 2-factor structure consisting of 'sensory' and 'affective' excluding two items such as splitting and heavy. As an attempt to further validate the KSF-MPQ, the purpose of this study was to confirm whether the KSF-MPQ model is an appropriate model for chronic pain patients in Korea by comparing several alternative models of the SF-MPQ. FINDINGS: A total of 150 chronic pain patients seeking treatment in Seoul, Korea, participated and completed the KSF-MPQ. Confirmatory factor analysis was conducted to evaluate the adequacy of the KSF-MPQ model and several alternative models. The results indicated that the adjusted KSF-MPQ model showed the best fit to the data among the models in chronic pain patients in Korea. CONCLUSIONS: The results showed the KSF-MPQ is cross-culturally equivalent to the original questionnaire. Thus, the KSF-MPQ is valid measurement for assessing the quality and intensity of pain to chronic pain patients and may be helpful in clinical and research settings in Korea.

Attentional bias towards emotional facial expressions in survivors of dating violence.

This study identified components of attentional bias (e.g. attentional vigilance, attentional avoidance and difficulty with disengagement) that are critical characteristics of survivors of dating violence (DV). Eye movements were recorded to obtain accurate and continuous information regarding attention. DV survivors with high post-traumatic stress symptoms (DV-High PTSS group; n = 20) and low post-traumatic stress symptoms (DV-Low PTSS group; n = 22) and participants who had never experienced DV (NDV group; n = 21) were shown screens displaying emotional (angry, fearful and happy) faces paired with neutral faces and negative (angry and fearful) faces paired with happy faces for 10 s. The results indicate that the DV-High PTSS group spent longer dwelling on angry faces over time compared with the DV-Low PTSS and NDV groups. This result implies that the DV-High PTSS group focused on specific trauma-related stimuli but does not provide evidence of an attentional bias towards threatening stimuli in general.

Psychometric evaluation of the sleep hygiene index: a sample of patients with chronic pain.

BACKGROUND: Sleep Hygiene Index (SHI) was designed to assess sleep hygiene. Although the SHI has shown adequate psychometric properties in a nonclinical sample, it has not been validated in a sample with chronic pain. Also, its factor structure, measurement error, and incremental validity over and above other factors affecting sleep quality have not been investigated in a nonclinical sample. Thus, this present study aimed to extend prior psychometric investigation of the SHI. Specifically, we evaluated the factor structure, measurement error, and incremental validity as well as the reliabilities and concurrent validity of the SHI in a sample with chronic pain. METHODS: A total of 161 patients seeking treatment in a tertiary pain center located in Seoul, Korea participated. To explore the factor structure of the SHI, we performed an exploratory factor analysis using principal component with varimax. Cronbach's alphas and intraclass correlation coefficients were computed to investigate internal consistency and 2-week test-retest stability of the SHI, respectively. Measurement error was estimated using standard error of measurement and minimum detectable change (MDC) of the SHI. For concurrent validity, Pearson correlations were calculated to examine the relations between the SHI and outcome measures including background variables. Also for incremental validity, a hierarchical multiple regression was performed in relation to sleep quality. RESULTS: Results indicated that two-factor solution is most appropriate; sleep disturbing behavior and environment (B/E) and irregular sleep-wake schedule. Results also showed that the internal consistencies and test-retest stability estimates of the SHI were deemed acceptable. At the 95% confidence level, the MDCs were 5.75 for 'sleep disturbing B/E,' 3.65 for 'irregular sleep-wake schedule,' and 7.49 points for total. The SHI was significantly correlated with age, depression, pain-related anxiety, and sleep quality. Also, sleep quality was significantly predicted by the irregular sleep-wake schedule subscale of the SHI, over and above background variables, pain intensity, depression, pain-related anxiety. CONCLUSIONS: The SHI has the reliability, measurement error, and concurrent and incremental validity support for assessing sleep hygiene in a sample with chronic pain.

Validation of the Korean version of the Pain Catastrophizing Scale in patients with chronic non-cancer pain.

PURPOSE: Pain catastrophizing often has been measured using the Pain Catastrophizing Scale (PCS). Studies of the PCS nearly consistently support its three-factor structure (i.e., helplessness, magnification, and rumination) and satisfactory psychometric properties across different countries and languages. This study aimed to assess the generalizability of the three-factor structure of the PCS to Korean patients with chronic non-cancer pain and to investigate reliability, measurement error, and construct validity of a Korean version of the PCS (K-PCS). METHODS: A total of 182 patients with chronic pain seeking treatment in a tertiary pain center located in Seoul, Korea, participated. RESULTS: Confirmatory factor analysis demonstrated the adequacy of the three-factor structure of the K-PCS; 'helplessness,' 'magnification,' and 'rumination.' The internal consistency for 'helplessness,' 'magnification,' 'rumination,' and total scale of the K-PCS were Cronbach's α = .90, .71, .86, and .93, respectively; test-retest stability, ICC = .77, .73, .65, and .79, respectively; the standard estimation of measurement, 1.93, 1.34, 2.13, and 3.72, respectively; the minimum detectable change, 5.33, 3.70, 5.89, and 10.28, respectively; and the limits of agreement, -7.66 to 9.20, -5.07 to 5.01, -7.30 to 6.86, and -15.26 to 16.46, respectively. At least moderate positive correlations were observed between the K-PCS and pain intensity, depression, and pain-related anxiety, and moderate negative correlations between the K-PCS and physical and psychological functioning. CONCLUSION: The K-PCS has the reliability, measurement error, and construct validity support for assessing pain catastrophizing in a Korean patient sample with chronic non-cancer pain.

Pain acceptance-based coping in complex regional pain syndrome Type I: daily relations with pain intensity, activity, and mood.

This study aimed to examine the temporal patterning of pain acceptance-based coping, activity, and mood in patients with complex regional pain syndrome Type I (CRPS-I), by using a daily diary method. A total of 30 patients with CRPS-I seeking treatment in a tertiary pain management center located in Seoul, Korea participated in the study. Multilevel random effects analyses indicated that (a) engagement in pain acceptance-based coping was significantly associated with lower same-day pain and negative mood and greater same-day activity and positive mood; (b) pain acceptance-based coping predicted increases in activity on the following day; (c) greater pain intensity was significantly associated with lower same-day pain acceptance-based coping and activity and greater same-day negative mood; and (d) pain intensity did not predict pain acceptance-based coping, activity, or mood on the following day. These findings suggest that patients with CRPS-I may benefit from responding to pain with acceptance. Further study and eventual application of this process in CRPS-I may improve upon the success of current approaches to this problem.

Application of attentional bias modification to reduce attentional bias and emotional reactivity to stress in mildly depressed individuals.

This study aims to verify the effectiveness of attentional bias modification (ABM) in reducing attentional bias related to depression, particularly in the later stages of attention as a pattern of difficulty in disengagement from depression-relevant stimuli, and to assess its effects on emotional reactivity to stress. A total of 78 participants were separated into four groups based on their levels of depression (minimal and mild) and the types of ABM. The positive ABM (pABM) trained participants to disengage their attention from depression-relevant stimuli and directed their attention toward more positive stimuli, whereas the neutral ABM (nABM) was designed to have no effect. The participants underwent a free-viewing task by eye tracker both before and after ABM to observe changes in attentional bias. Subsequently, they reported their emotional response after a stress-inducing task. The group of mildly depressed participants receiving pABM showed significantly less attention to depression-relevant negative affective stimuli and reported significantly decreased negative emotional reactivity to stress compared to the other groups. pABM had an effect on decreasing difficulty in disengaging from depression-relevant negative affective words (DW). However, it did not increase the dwell time on positive affective words (PW) in the current study. This might be due to the short duration of the application of ABM. The current study conducted ABM twice in 1 day, and this might not be enough to increase the dwell time on PA. This study verified that the ABM effectively decreased the attentional bias of depression and its relevant symptom, emotional reactivity to stress.

Attentional bias for high-calorie food cues by the level of hunger and satiety in individuals with binge eating behaviors.

Introduction: The abnormal hyperreactivity to food cues in individuals with binge eating behaviors could be regulated by hedonic or reward-based system, overriding the homeostatic system. The aim of the present study was to investigate whether attentional bias for food cues is affected by the level of hunger, maintaining the normal homeostatic system in individuals with binge eating behaviors. Methods: A total of 116 female participants were recruited and divided into four groups: hungry-binge eating group (BE) (n = 29), satiated BE (n = 29), hungry-control (n = 29), satiated control (n = 29). While participants completed a free-viewing task on high or low-calorie food cues, visual attentional processes were recorded using an eye tracker. Results: The results revealed that BE group showed longer initial fixation duration toward high-calorie food cues in both hunger and satiety condition in the early stage, whereas the control group showed longer initial fixation duration toward high-calorie food cues only in hunger conditions. Moreover, in the late stage, the BE group stared more at the high-calorie food cue, compared to control group regardless of hunger and satiety. Discussion: The findings suggest that automatic attentional bias for food cues in individuals with binge eating behaviors occurred without purpose or awareness is not affected by the homeostatic system, while strategic attention is focused on high-calorie food. Therefore, the attentional processing of food cues in binge eating group is regulated by hedonic system rather than homeostatic system, leading to vulnerability to binge eating.

Differences in arousal and valence on the Korean phoneme of artificial voice between Korean and Chinese women.

BACKGROUND: Although active research is in progress in the fields of psychology and linguistics on the emotional characteristics of the symbol and meaning of sound itself, since the systematic emotional model is not applied, each researcher uses a subjective concept and acts as an obstacle to the expansion of research. There is a limitation in that it cannot be confirmed whether the sound symbol has universality regardless of cultural differences between different languages. METHODS: In this study, the difference between the arousal and valence of emotions felt toward Hangul phonemes was explored according to consonant and vowel through comparison between Korean and Chinese women. 38 Korean women and 32 Chinese women were recruited, and an online experiment was conducted in which arousal and valence were reported for 42 Hangeul phoneme sound stimuli. RESULTS: As a result of comparing the arousal and valence of each group, Koreans showed significantly higher arousal scores than Chinese, and these results showed different differences according to consonant and vowel. In valence, there was a difference between nationalities only according to consonant indicating that Koreans showed lower positivity toward aspirated sounds than Chinese. Through these results, it was confirmed that the emotional meaning of the sound symbol between different languages is different, which can be affected by consonant and vowels. CONCLUSION: This study identified differences in emotional perception between cultures by using two dimensions of emotions, arousal, and valence, which are systematized for sound symbols, and suggests implications for the relationship between sound symbol and emotions and cultural differences in the future.

The role of direct contact in forming peace-oriented international relations of a divided country: Focusing on the division of the Korean Peninsula.

BACKGROUND: The division of the Korean peninsula involved many neighbouring countries in the Korean War. The relations with those countries have since been reorganised due to active exchange. This study examined how the quantity and quality of contact with traditional alliance (US and Japan) and strategic partner (China and Russia) countries affected their national images. METHODS: To this end, this study analyzed the relation with the national image by measuring the quantity and quality of contact of an individual with each country. The quantity of contact included an evaluation of the individual's subjective amount of contact, contact path, and contact status, and the quality of contact was measured as an evaluation for the pleasure, competitiveness, intimacy, spontaneity, and necessity when contacting each country's culture. A total of 387 participants were divided into two groups based on the presence of direct contact and the quantity and quality of their contact and national images were examined. The participants were followed by a completion of the self-questionnaires including the Culture Experience Questionnaire, National Image Questionnaire, and demographic information questionnaire. RESULTS: The results of this study are as follow: first, regardless of the type of country, the national image was highly correlated with the degree of subjective contact evaluated by individuals, but there was a weak tendency with contact quality. Second, there was no significant interaction between the country type and contact status for national image, however, different national images for each country were detected. In other word, for contact quantity, contact groups showed more positive national images compared to non-contact groups in Russia, but not Japan, China, and the US. For contact quality, the positive contact experience group showed more positive national images compared to the negative contact experience group, but only in traditional alliance countries. CONCLUSION: This study highlights the importance of implementing different strategies for countries to maintain peaceful international relations.

Primary Production in the Kara, Laptev, and East Siberian Seas.

Understanding of the primary production of phytoplankton in the Kara Sea (KS), the Laptev Sea (LS), and the East Siberian Sea (ESS) remains limited, despite the recognized importance of phytoplankton in the Arctic Ocean. To address this knowledge gap, we conducted three NABOS (Nansen and Amundsen Basins Observational System) expeditions in 2013, 2015, and 2018 to measure in situ primary production rates using a 13C-15N dual-tracer method and examine their major controlling factors. The main goals in this study were to investigate regional heterogeneity in primary production and derive its contemporary ranges in the KS, LS, and ESS. The daily primary production rates in this study (99 ± 62, 100 ± 77, and 56 ± 35 mg C m-2 d-1 in the KS, LS, and ESS, respectively) are rather different from the values previously reported in each sea mainly because of spatial and regional differences. Among the three seas, a significantly lower primary production rate was observed in the ESS in comparison to those in the KS and LS. This is likely mainly because of regional differences in freshwater content based on the noticeable relationship (Spearman, rs = -0.714, p < 0.05) between the freshwater content and the primary production rates observed in this study. The contemporary ranges of the annual primary production based on this and previous studies are 0.96-2.64, 0.72-50.52, and 1.68-16.68 g C m-2 in the KS, LS, and ESS, respectively. Further intensive field measurements are warranted to enhance our understanding of marine microorganisms and their community-level responses to the currently changing environmental conditions in these poorly studied regions of the Arctic Ocean.

Psychometric properties of a Korean version of the Chronic Pain Acceptance Questionnaire in chronic pain patients.

PURPOSE: Accepting pain rather than trying to control it has been the focus of recent pain management research. Pain acceptance often has been assessed using the chronic pain acceptance questionnaire (CPAQ). This study aimed to evaluate the factor structure and other psychometric properties of a Korean language version of the CPAQ (KCPAQ). METHODS: This study used two archival data sets collected over two different time periods at the same site in Korea, generating two samples (Total N = 361). RESULTS: Exploratory factor analysis using sample 1 (N = 182) provided support for the same two-factor structure as the original English CPAQ. Confirmatory factor analysis using sample 2 (N = 179) demonstrated the adequacy of the two-factor model obtained from sample 1. Samples 1 and 2 were combined for the reliability and validity analyses. The results indicated that the KCPAQ has good internal consistency and test-retest stability. The KCPAQ was significantly correlated with pain intensity, pain-related anxiety, depressive symptoms, physical adjustment, and psychosocial adjustment. CONCLUSION: The KCPAQ has reliability and construct validity support for the measurement of pain acceptance in a Korean patient sample with chronic pain.

Attentional bias to violent images in survivors of dating violence.

This study investigated the time-course characteristics of attentional bias, such as vigilance and maintenance, towards violent stimuli in dating violence (DV) survivors. DV survivors with PTSD symptoms (DV-PTSD group; n=14), DV survivors without PTSD symptoms (Trauma Control group; n=14), and individuals who were never exposed to dating violence (NDV group; n=15) viewed slides that presented four categories of images (violent, dysphoric, positive, and neutral) per slide, for ten seconds. Our results revealed that the DV-PTSD group spent more time on violent stimuli than did the Trauma Control or NDV groups. The DV survivors, both with and without PTSD symptoms, spent more time on dysphoric stimuli and less time on happy stimuli than did the NDV group. In addition to the effects of PTSD, researchers should also be considering the effects of simple traumatic exposure.

Functional Extended Redundancy Analysis.

We propose a functional version of extended redundancy analysis that examines directional relationships among several sets of multivariate variables. As in extended redundancy analysis, the proposed method posits that a weighed composite of each set of exogenous variables influences a set of endogenous variables. It further considers endogenous and/or exogenous variables functional, varying over time, space, or other continua. Computationally, the method reduces to minimizing a penalized least-squares criterion through the adoption of a basis function expansion approach to approximating functions. We develop an alternating regularized least-squares algorithm to minimize this criterion. We apply the proposed method to real datasets to illustrate the empirical feasibility of the proposed method.

The effect of feedback in virtual attention training on orienting attention in individuals with sluggish cognitive tempo.

OBJECTIVE: This study was conducted to assess the effectiveness of feedback in a virtual attention training program to improve the attentional characteristics of sluggish cognitive tempo (SCT). METHOD: The SCT group (N = 60) and control group (N = 30) were identified, and the attention network test-revised (ANT-R) was performed to measure attention characteristics. Based on this result, a virtual reality (VR) feedback attention training program was developed to improve the efficiency of engagement and disengagement of attention in SCT. Sixty participants with SCT were recruited and grouped into two conditions: VR feedback (n = 30) and no-feedback (n = 30) conditions. RESULTS: The results show that the VR attention training program with feedback significantly improves the attention-orienting network. CONCLUSION: This suggests that it is necessary to provide immediate feedback for effective attention training for SCT and continuous intervention may be possible when feedback is provided together.

Diminished ability to integrate target stimuli with context during emotional recognition in individuals with broad autism phenotype.

Individuals with broad autism phenotype (BAP) have a tendency not to integrate emotional stimuli with the surrounding context. They have also shown different patterns and abilities in processing positive and negative emotions. This study aimed to examine whether the effect of context on target stimuli could vary depending on the type of target emotion in individuals with BAP. Based on the Broad Autism Phenotype Questionnaire (BAPQ) and Autism-Spectrum Quotient (AQ), 36 individuals with BAP and 33 healthy controls were selected. All the participants performed an overlap-emotional task consisting of six conditions: 2 (congruence: congruent and incongruent) × 3 (emotion: fearful, sad, and happy). Reaction time and accuracy were measured as dependent variables. The results revealed that the individuals with BAP showed no difference in reaction time between the condition of congruence and incongruence, but that the control group was faster to categorize facial expression on the condition of congruence than that of incongruence regardless of the type of target emotion. There were no differences between the two groups in any of the conditions with regard to accuracy. These findings indicate that individuals with BAP tend not to integrate target emotions with contextual information, a feature that could worsen the speed of emotional recognition in individuals with BAP. This study confirmed that the individuals with BAP have different cognition patterns in emotional recognition than the control group.

Self-referential processing in individuals with nonsuicidal self-injury: An fMRI study.

Nonsuicidal self-injury (NSSI) is associated with considerable deficits in managing negative self-directed internal experiences. The present study explores the neurophysiological correlates of self-referential processing in individuals with NSSI. A total of 26 individuals with NSSI (≥5 episodes of NSSI behavior in the past year, without suicide attempts) and 35 age-, sex-, education-, and intelligence quotient (IQ)-matched controls participated in this study. Participants underwent fMRI scanning as they performed a personal relevance rating task, which required them to evaluate the personal relevance of emotional words. As predicted, we found that individuals engaging in NSSI tended to rate negative adjectives as more relevant and positive adjectives as less relevant. An analysis of functional neuroimaging data showed that the NSSI group had increased activity relative to the control group in the inferior parietal lobe, inferior temporal gyrus, calcarine, insula, and thalamus in response to positive adjectives. The NSSI group also demonstrated greater activation in the calcarine and reduced activation in the inferior frontal gyrus in response to negative self-referential stimuli compared with the control group. In addition, increased right inferior parietal lobe activity during positive self-referential processing was correlated with reduced suicidal ideation in the NSSI group. Our study provides neural evidence for self-referential processing bias in individuals with NSSI and highlights the need for further research to clarify the pathophysiological features that are specific to NSSI.

Properties of Central and Peripheral Concepts of Emotion in Japanese and Korean: An Examination Using a Multi-Dimensional Model.

The concept of emotion can be organized within a hypothetical space comprising a limited number of dimensions representing essential properties of emotion. The present study examined cultural influences on such conceptual structure by comparing the performance of emotion word classification between Japanese and Korean individuals. Two types of emotional words were used; central concepts, highly typical examples of emotion, and less typical peripheral concepts. Participants classified 30 words into groups based on conceptual similarity. MDS analyses revealed a three-dimensional structure with valence, social engagement, and arousal dimensions for both cultures, with the valence dimension being the most salient one. The Japanese prioritized the social engagement over the arousal while the Koreans showed sensitivities to the arousal dimension. Although the conceptual structure was similar for the two countries, the weight of importance among the three dimensions seems to be different, reflecting each culture's values and communication styles.