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Soft wearable robotic gloves based on tendon-sheath mechanism are widely developed for assisting people with a loss of hand mobility. For these robots, knowing the fingertip forces applied to deformable objects is crucial in successfully grasping them without causing excessive deformations. Existing studies presented methods to predict fingertip force applied to rigid objects only using information from the actuation system. However, forces applied to deformable objects are subject to non-linearity and hysteresis in relation to the objects’ stiffness, which further complicates the problem. Therefore, this letter proposes a deep-learning model that can accurately estimate the fingertip forces applied to deformable objects using motor encoder values, motor current, and wire tension. Our model is based on an integrated system of Long Short-Term Memory models that 1) estimates stiffness of the grasped objects and 2) incorporates the estimated stiffness for predicting the fingertip forces. When evaluated using a TSM-based soft wearable robot, the proposed model recorded fingertip force estimation of 0.702 N RMSE, achieving 45% increase in accuracy compared to LSTM that does not consider the objects’ stiffness. The applicability of our method was evaluated by estimating the fingertip forces applied to common daily items and performing real-time force control.

BACKGROUND IgG4-related sclerosing cholangitis (IgG4-RSC) is an uncommon benign disease, and its rarer, isolated and mass-forming subtype poses a significant challenge to differential diagnosis from cholangiocarcinoma of the extrahepatic bile duct. We herein report a case of isolated IgG4-RSC with an obstructing bile duct mass, for which extrahepatic bile duct resection was performed under the impression of proximal common bile duct (CBD) cancer. CASE SUMMARY A 79-year-old male was admitted for jaundice that had developed 1 mo prior. There was no family history for autoimmune diseases or biliary cancer. Computed tomography (CT) and magnetic resonance cholangiopancreaticography revealed a short segmental concentric wall thickening of the proximal CBD with diffuse dilatation of the bile duct to the periphery. The endoscopic biopsy specimen showed no malignant cells. Positron emission tomography-CT showed a focal hypermetabolic lesion (SUVmax 4.2) in and around the proximal CBD area. With the impression of proximal CBD cancer, we performed segmental resection of the extrahepatic bile duct. Histopathology demonstrated marked sclerosis with diffuse lymphoplasmacytic infiltration and some eosinophils. Immunohistochemical staining for IgG4 showed increased positivity in some areas (up to 30/high-power field) and IgG4+/IgG+ cell ratio as 30%-50%. Pathologists’ impression was IgG4-related sclerosing disease. Follow-up serum IgG4 levels were continuously elevated; however, no evidence of relapse or other organ involvement related to IgG4-RSC presented. CONCLUSION Isolated and mass-forming IgG4-RSC displays striking similarity with cholangiocarcinoma. To avoid unnecessary major surgery, high index of suspicion is needed.

The practical operation of wearable robots requires intuitive, compact, yet reliable control interfaces. However, current myoelectric interfaces based on surface electromyography (EMG) often fail to achieve these requirements by demanding multiple sensors and exhibiting unreliable performance under limb posture changes. In this study, we show that a myoelectric interface on the musculotendinous junctions (MTJs) of the flexor digitorum superficialis (FDS) enables reliable control of a robotic glove with a single EMG sensor by identifying power grasp intentions. We found that the myoelectric signals from the MTJs of the FDS show significantly increased amplitudes exclusively when a power grasp is performed, regardless of the arm posture. We systematically verified that, in identifying power grasp intentions, the proposed single-sensor myoelectric interface even outperforms a five-sensor myoelectric interface around the proximal forearm. By exploiting the unique biological feature of the MTJs, we devised two myoelectric control methods for a robotic glove—Dual-threshold control and Morse-code control—and further showed their performances in practical operations. Dual-threshold control enables direct co-operation between the user and the robotic glove, and Morse-code control provides various command options for the user.

Background IPNB is very rare disease and most previous studies on IPNB were case series with a small number due to low incidence. The aim of this study is to validate previously known clinicopathologic features of intraductal papillary neoplasm of bile duct (IPNB) based on the first largest multicenter cohort. Methods Among 587 patients previously diagnosed with IPNB and similar diseases from each center in Korea, 387 were included in this study after central pathologic review. We also reviewed all preoperative image data. Results Of 387 patients, 176 (45.5%) had invasive carcinoma and 21 (6.0%) lymph node metastasis. The 5-year overall survival was 80.9% for all patients, 88.8% for IPNB with mucosal dysplasia, and 70.5% for IPNB with invasive carcinoma. According to the “Jang & Kim's modified anatomical classification,” 265 (68.5%) were intrahepatic, 103 (26.6%) extrahepatic, and 16 (4.1%) diffuse type. Multivariate analysis revealed that tumor invasiveness was a unique predictor for survival analysis. (p = 0.047 [hazard ratio = 2.116, 95% confidence interval 1.010–4.433]). Conclusions This is the first Korean multicenter study on IPNB through central pathologic and radiologic review process. Although IPNB showed good long-term prognosis, relatively aggressive features were also found in invasive carcinoma and extrahepatic/diffuse type.

BACKGROUND Panniculitis, polyarthritis, and pancreatitis (PPP) syndrome is a triad comprising an extremely rare extra-pancreatic complication of pancreatic disease. Herein, we describe a patient with PPP syndrome caused by fistula formation between the inferior vena cava (IVC) and pancreatic pseudocyst. CASE SUMMARY A 64-year-old man visited the hospital with bilateral leg pain that began one week prior. He had no specific diseases, except hypertension. His vital signs were normal. Blood test revealed the following findings: White blood cell count, 28690/µL; amylase level, 9055 U/L; lipase level, 2089 U/L; and C-reactive protein level, 12.94 mg/dL. Computed tomography of the pancreas revealed recent acute pancreatitis. Nonsteroidal anti-inflammatory drugs were administered with no improvement. After steroid administration, pain slightly improved. Skin lesions were diagnosed as panniculitis. Bone scan and knee magnetic resonance imaging revealed osteoarthritis and bone marrow infarctions. Surgical treatment was considered; total pancreatectomy with splenectomy was performed. A pseudocyst was present posterior to the head of the pancreas, forming a fistula with the suprarenal IVC. After surgery, amylase and lipase levels decreased. However, the patient died of an uncontrolled infection on the 13th postoperative day. CONCLUSION PPP syndrome should be suspected when accompanied by skin and joint lesions. Delays in diagnosis could have catastrophic consequences.

Aims and objectives To identify Zika virus-related knowledge, attitudes to Zika virus and health motivations of pregnant women, women preparing for pregnancy and their partners, and to identify factors that influence preventive health behaviours for Zika virus infection. Background Prevention of Zika virus infection is becoming a major worldwide public health effort. The high-risk group for Zika virus infection comprises women who are pregnant or preparing for pregnancy. Few studies have addressed preventive health behaviours for Zika virus infection by gender. Design This study was a descriptive cross-sectional survey. Methods Participants (112 males and 147 females) were selected by convenience sampling from three obstetric clinics located in South Korea. Women and their partners who visited obstetric clinics during pregnancy or preparing for pregnancy were included as subjects. Results Factors associated with preventive health behaviours for Zika virus were checking infection status of Zika virus on destinations when planning a trip and attitudes to Zika virus in males and age, educational level, intention to travel to Zika virus endemic countries, attitudes to Zika virus and health motivation in females. Conclusions Factors that influence preventive health behaviours for Zika virus were different by gender. However, attitudes to Zika virus were influential to both genders. Gender differences should be considered in development of health policies to improve preventive health behaviours for Zika virus. Younger and less educated women are to be targeted, and health management programmes should be developed to promote health motivation. Relevance to clinical practice Pregnant women, women preparing for pregnancy and their partners need education and public health promotion to improve self-management during travel to places where Zika virus is endemic. Health policies and health management programmes considering age and educational background should be developed to promote health motivation in women of childbearing age.

Objective. This study investigates the efficacy of electroencephalography (EEG) centered around the user’s ears (ear-EEG) for a speech-imagery-based brain–computer interface (BCI) system. Approach. A wearable ear-EEG acquisition tool was developed and its performance was directly compared to that of a conventional 32-channel scalp-EEG setup in a multi-class speech imagery classification task. Riemannian tangent space projections of EEG covariance matrices were used as input features to a multi-layer extreme learning machine classifier. Ten subjects participated in an experiment consisting of six sessions spanning three days. The experiment involves imagining four speech commands (‘Left,’ ‘Right,’ ‘Forward,’ and ‘Go back’) and staying in a rest condition. Main results. The classification accuracy of our system is significantly above the chance level (20%). The classification result averaged across all ten subjects is 38.2% and 43.1% with a maximum (max) of 43.8% and 55.0% for ear-EEG and scalp-EEG, respectively. According to an analysis of variance, seven out of ten subjects show no significant difference between the performance of ear-EEG and scalp-EEG. Significance. To our knowledge, this is the first study that investigates the performance of ear-EEG in a speech-imagery-based BCI. The results indicate that ear-EEG has great potential as an alternative to the scalp-EEG acquisition method for speech-imagery monitoring. We believe that the merits and feasibility of both speech imagery and ear-EEG acquisition in the proposed system will accelerate the development of the BCI system for daily-life use.

Transcranial direct current stimulation (tDCS) is a neuromodulation technique that applies a small electrical current to a user's scalp to stimulate the brain. This preliminary study is conducted to examine the effect of tDCS to the performance of a speech-imagery-based brain-computer interface (SI-based BCI) system. SI-based BCI experiments were conducted on six participants where three participants receive tDCS and the other three receive sham-stimulation. The comparison between the accuracy of pre-stimulation and post-stimulation sessions of tDCS and sham-stimulation group suggests that a tDCS can slightly boosts the performance of a SI-based BCI system. However, the experiment is needed to be repeated on a greater number of participants to confirm the theory.

Brain-computer interfaces allow direct control over devices without any physical action by the user. Motor imagery-based brain-computer interfaces analyze spatial patterns from brain signals elicited when the user imagines execution of a specific behavior. One of the ways to obtain such brain signals is with electroencephalography, which measures signals over the scalp. In this paper, we analyzed the brain patterns from when the users performed different motor imagery tasks and applied them to navigate a simulated drone. The drone was controlled asynchronously, with the user's intentions continuously analyzed throughout the entire drone control period. By navigating the drone in two different scenarios using either 4 or 6 control commands and by comparing control performance when controlling the drone with either a BCI or a keyboard, we have shown the feasibility of motor imagery for asynchronous control of drones for both two- and three-dimensional device control.

Backgrounds/Aims The purpose of this retrospective study was to determine the association between prognostic nutritional index (PNI) and recurrence of hepatocellular carcinoma after a curative resection. Methods Between 2007 to 2019, 130 patients who underwent curative hepatectomy for hepatocellular carcinoma were enrolled. PNI was calculated. Its cutoff value was identified through receiver operating characteristic curve analysis. According to PNI, patients were divided into two groups. Univariate and multivariate analyses were performed to identify independent risk factors for recurrence. Results The cutoff value of PNI was 52. In univariate analysis, alcoholic liver cirrhosis (p = 0.041), protein induced by vitamin K antagonist- II ≥ 200 (p = 0.012), indocyanine green retention test (ICG R15) >10% (p = 0.001), estimated blood loss ≥ 800 mL (p = 0.037), tumor size (p = 0.001), microvascular invasion (p = 0.023), T-stage (p = 0.001), and PNI < 52 (p = 0.001) were significant factors affecting the recurrence. In multivariate analysis, alcoholic liver cirrhosis (p = 0.046), ICG R15 >10% (p = 0.025), T-stage (p = 0.003), and PNI < 52 (p = 0.046) were independent prognostic factors for disease-free survival. Conclusions PNI, a nutritional and immunologic factor, is an independent prognostic factor that can predict the recurrence of hepatocellular carcinoma in patients undergoing a curative resection.

Soft robots have been extensively researched due to their flexible, deformable, and adaptive characteristics. However, compared to rigid robots, soft robots have issues in modeling, calibration, and control in that the innate characteristics of the soft materials can cause complex behaviors due to non-linearity and hysteresis. To overcome these limitations, recent studies have applied various approaches based on machine learning. This paper presents existing machine learning techniques in the soft robotic fields and categorizes the implementation of machine learning approaches in different soft robotic applications, which include soft sensors, soft actuators, and applications such as soft wearable robots. An analysis of the trends of different machine learning approaches with respect to different types of soft robot applications is presented; in addition to the current limitations in the research field, followed by a summary of the existing machine learning methods for soft robots.

This paper presents a computational framework for providing affective labels to real-life situations, called A-Situ. We first define an affective situation, as a specific arrangement of affective entities relevant to emotion elicitation in a situation. Then, the affective situation is represented as a set of labels in the valence-arousal emotion space. Based on psychological behaviors in response to a situation, the proposed framework quantifies the expected emotion evoked by the interaction with a stimulus event. The accumulated result in a spatiotemporal situation is represented as a polynomial curve called the affective curve, which bridges the semantic gap between cognitive and affective perception in real-world situations. We show the efficacy of the curve for reliable emotion labeling in real-world experiments, respectively concerning (1) a comparison between the results from our system and existing explicit assessments for measuring emotion, (2) physiological distinctiveness in emotional states, and (3) physiological characteristics correlated to continuous labels. The efficiency of affective curves to discriminate emotional states is evaluated through subject-dependent classification performance using bicoherence features to represent discrete affective states in the valence-arousal space. Furthermore, electroencephalography-based statistical analysis revealed the physiological correlates of the affective curves.

Ear-EEG is an alternative EEG acquisition method to the scalp-EEG conventionally used in Brain-Computer Interface (BCI). It is a more comfortable, discreet, and fashionable method comparing to the scalp-EEG. This work proposes an Ear-EEG-based BCI system that detects and utilizes the concentration level as the BCI signal. The experiments conducted in this study shows that the concentration level can be detected from the Ear-EEG acquiring around the user's ears. In the online experiment, our BCI system achieve the average true positive rate of 83% with the performance time of 3.98 seconds and false discovery rate of 16%. This study serves as another proof that Ear-EEG is a reliable EEG acquisition method especially for the BCI system that aims for the daily-life applications for normal healthy users.

The purpose of this study was to examine the relationship of subepidermal moisture and early stage pressure injury by visual skin assessment in elderly Korean.Twenty-nine elderly participated at a particular nursing home. Data were collected for 12 weeks by one wound care nurse. Visual skin assessment and subepidermal moisture value were measured at both buttocks, both ischia, both trochanters, sacrum, and coccyx of each subject once a week.Subepidermal moisture value of stage 1 pressure injury was significantly higher than that of no injury and blanching erythema. After adjustment with covariates, odds ratios of blanching erythema to normal skin and stage 1 pressure injury to blanching erythema/normal skin were statistically significant (p 0.05). Odds ratio of blanching erythema to normal skin was 1.003 (p = .047) by 1-week prior subepidermal moisture value, and that of concurrent subepidermal moisture value was 1.004 (p = .011). Odds ratio of stage 1 pressure injury to normal skin/blanching erythema was 1.003 (p = .005) by 1-week prior subepidermal moisture value, and that for concurrent subepidermal moisture value was 1.007 (p = .030). Subepidermal moisture was associated with concurrent and future (1 week later) skin damage at both trochanters.Subepidermal moisture would be used to predict early skin damage in clinical nursing field for the effective pressure injury prevention.

Key Clinical Message Aberrant subvesical bile ducts are rare anatomical structures. Damage to these ducts leads to bile leakage and can result in life‐threatening complications. Surgeons should be cautious that such a structure may be present, and surgery should be performed with the correct surgical field to prevent damage to these structures.

Depression diagnosis is one of the most important issues in psychiatry. Depression is a complicated mental illness that varies in symptoms and requires patient cooperation. In the present study, we demonstrated a novel data-driven attempt to diagnose depressive disorder based on clinical questionnaires. It includes deep learning, multi-modal representation, and interpretability to overcome the limitations of the data-driven approach in clinical application. We implemented a shared representation model between three different questionnaire forms to represent questionnaire responses in the same latent space. Based on this, we proposed two data-driven diagnostic methods; unsupervised and semi-supervised. We compared them with a cut-off screening method, which is a traditional diagnostic method for depression. The unsupervised method considered more items, relative to the screening method, but showed lower performance because it maximized the difference between groups. In contrast, the semi-supervised method adjusted for bias using information from the screening method and showed higher performance. In addition, we provided the interpretation of diagnosis and statistical analysis of information using local interpretable model-agnostic explanations and ordinal logistic regression. The proposed data-driven framework demonstrated the feasibility of analyzing depressed patients with items directly or indirectly related to depression.

Introduction The purpose of this retrospective study was to determine the association between the prognostic nutritional index (PNI) and recurrence of hepatocellular carcinoma after curative resection. Methods Between 2007 to 2019, 130 patients who underwent curative hepatectomy for hepatocellular carcinoma were enrolled. The PNI was calculated, and the cutoff value was identified through receiver operating characteristic curve analysis. According to the PNI, patients were divided into two groups. Univariate and multivariate analyses were performed to identify independent risk factors for recurrence. Results The cutoff value of the PNI was 52. In the univariate analysis, alcoholic liver cirrhosis (p = 0.041), protein induced by vitamin K antagonist-II ≥ 200 (p = 0.012), indocyanine green retention test (ICG R15) > 10% (p = 0.001), estimated blood loss ≥ 800 mL (p = 0.037), tumor size (p = 0.001), microvascular invasion (p = 0.023), T-stage (p = 0.001), and PNI 10% (p = 0.025), T-stage (p = 0.003), and PNI < 52 (p = 0.046) were independent prognostic factors for disease-free survival. Conclusions The PNI, a nutritional and immunologic factor, is an independent prognostic factor that can predict the recurrence of hepatocellular carcinoma in patients undergoing curative resection.

Introduction It is known that gallbladder cancer (GBC) in the neck or cystic duct (NC-GBC) has a better prognosis than GBC in the fundus or body (FB-GBC), but systematic studies on this are insufficient. We performed this study to investigate the impact of longitudinal tumor location on postoperative outcomes in patients undergoing resection for GBC. Methods A retrospective study was conducted for patients who underwent a radical resection for GBC from February 2008 to November 2017 at the Dankook University Hospital. A total of 98 patients underwent surgery for GBC, of which 77 patients who underwent curative intent surgery were included in the study. They were classified into FB-GBC and NC-GBC groups according to longitudinal tumor location, and the postoperative outcomes were compared and analyzed. Results There were no significant differences in the clinicopathological characteristics, TNM stage, postoperative complications, and in-hospital mortality between two groups. However, NC-GBC significantly showed more sclerotic gross type, poorer differentiation, and more lymphatic and perineural microinvasion. The radical resection rate was statistically higher in FB-GBC group (93.1% vs. 73.7%; p = 0.036) and adjuvant 5-FU based CCRT was more carried out in NC-GBC group (19.0% vs. 57.9%; p < 0.001). The recurrence rates after surgery was statistically higher in NC-GBC group (25.9% vs. 52.6%, p = 0.047), but there were no differences in disease-free survival (DFS) and overall survival (OS). Conclusions Although NC-GBC showed more aggressive microscopic pathological findings and higher recurrence rate than FB-GBC, there were no differences in DFS and OS according to longitudinal tumor location of GBC.

Previous pattern recognition algorithms using surface electromyography (sEMG) have been developed for subsets of predefined hand movements without considering muscle structure. In order to decode hand movements, it is important to know which movements are appropriate for PR due to the different independence of movements between individuals and the high correlated characteristics of sEMG patterns between movements. This paper proposes a method to personally rank the order of hand movements from subsets (31 finger flexion, 31 finger extension, and 4 wrist movements in this paper). The movements were sorted into a ranked order with respect to the locations of the electrodes on the proximal forearm and the distal forearm. We evaluated the classification error as the number of desired movements (N m) changed. The maximum N m with an error lower than 10% was 20 for the proximal forearm and 10 for the distal forearm from ranked movements of individuals. Our method could help to identify the optimized order of hand movements considering the personal characteristics of each individual.

In this paper we present a hybrid brain-computer interface (BCI) system that manipulates simultaneous localization and mapping (SLAM) for convenient control of a robot. Due to the low accuracy of classifying multi-class neural signals, using brain signals alone has been considered inadequate for precise control of a robotic systems. To overcome the negative aspects of BCI systems, we introduce a hybrid system where the BCI control of a robot is aided by SLAM. Subjects used electroencephalography (EEG) and electrooculography (EOG) to remotely control a turtle robot that is running SLAM in a maze environment. With the supplementary information on the surroundings provided by SLAM, the robot could calculate potential paths and rotate at precise angles while subjects give only high-level commands. Subjects could successfully navigate the robot to the destination showing the potential of utilizing SLAM along with BCIs.

Most user interfaces require motion; the motor-impaired therefore do not have many options to choose from. Electroencephalography (EEG) and the analysis of eye movement are two of the commonly proposed methods for enhancing the user experiences of the motor-impaired. In this paper, we propose an electrooculography (EOG)/EEG-based hybrid BCI that combines the strengths of EOG and EEG by using them simultaneously. We have shown the effectiveness of EOG/EEG-based hybrid BCIs by implementing the proposed interface and applying it to a chess game. Through this paper, we hope to provide improved interface systems for patients who have physical disabilities.

Objective Brain-computer interfaces (BCIs) based on motor imagery (MI) are commonly used for control applications. However, these applications require strong and discriminant neural patterns for which extensive experience in MI may be necessary. Inspired by the field of rehabilitation where embodiment is a key element for improving cortical activity, our study proposes a novel control scheme in which virtually embodiable feedback is provided during control to enhance performance. Methods Subjects underwent two immersive virtual reality control scenarios in which they controlled the two-dimensional movement of a device using electroencephalography (EEG). The two scenarios only differ on whether embodiable feedback, which mirrors the movement of the classified intention, is provided. After undergoing each scenario, subjects also answered a questionnaire in which they rated how immersive the scenario and embodiable the feedback were. Results Subjects exhibited higher control performance, greater discriminability in brain activity patterns, and enhanced cortical activation when using our control scheme compared to the standard control scheme in which embodiable feedback is absent. Moreover, the self-rated embodiment and presence scores showed significantly positive linear relationships with performance. Significance The findings in our study provide evidence that providing embodiable feedback as guidance on how intention is classified may be effective for control applications by inducing enhanced neural activity and patterns with greater discriminability. By applying embodiable feedback to immersive virtual reality, our study also serves as another instance in which virtual reality is shown to be a promising tool for improving MI.

Ear-EEG is an EEG acquisition method that record EEG signal from inside the user's ear. This study fabricated an ear-EEG device and tested its ability to detect alpha activity when the subject is in a wakeful relaxation state and its performance in binary auditory P300 BCI system. The ear-EEG fabricated in this study were able to detect the alpha activity from the subjects. In auditory P300 experiment, the highest accuracy and ITR was 95.61% and 2.9685 bits/min, respectively. The surveys given to the participants point out that the ear-EEG devices in this work were easily wearable and very comfortably. These results suggest that ear-EEG is a promising alternative EEG-acquisition method that is more user-friendly and suitable for BCI system that aims for daily-life usage comparing to the conventional scalp-EEG method.

In this study, we propose an effective training method for 2-class motor imagery tasks on brain computer interface (BCI) systems viable even for distracting environments. For non-invasive BCIs, it is difficult to capture event-related desynchronization (ERD) and event-related synchronization (ERS) signals through electroencephalogram (EEG) in places where it is difficult for subjects to concentrate. To improve concentration under a distracting environment, our proposed training method implemented a graphical interface as a source of visual feedback. The performance of the implemented training method is evaluated by comparing its results with those of a training method that does not support visual feedback. The experiments are held while a variety of noises are produced to simulate a distracting environment. The results of the experiment demonstrate the effectiveness of the proposed training method in distracting environments for 2-class motor imagery tasks.

HG1 is a Leu-rich antimicrobial peptide (AMP). Previously, the peptide was shown to lose its activity in human serum although it possessed potent and broad spectrum antimicrobial activity against a wide range of pathogenic microbes. In an attempt to design an HG1 isomer that can overcome the problem of HG1, a structure–activity relationship study was conducted by substitution of each of five Leu residues with a Gln residue. Each substitute was tested for its antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) or Candida strains. In addition, the antimicrobial activity of HG1 isomers was examined in the presence of glycosaminoglycans or lipid components occurring in the extracellular matrix, human serum and wound fluid. As a result, it was determined that the third residue (Leu) in the sequence of HG1 was mainly responsible for abrogation of its antimicrobial activity in human serum or wound fluid. An HG1 isomer (L3Q) with a Gln-3 substitution exhibited a potent antibacterial activity in 50% human serum. While the anti-MRSA activity of L3Q was equivalent to that of HG1, its anti-Candida activity was found to be substantially reduced. In order to improve anti-Candida activity of L3Q, its cationicity was enhanced by replacement of the C-terminal Ala-19 with a Lys residue. Overall, an HG1 isomer with two substitutions of Gln-3 and Lys-19, named haloganan, was verified to have an advantage over HG1 in that it exerted its potent antimicrobial activity under conditions containing human serum and/or wound fluid.

Brain-computer interfaces (BCIs) that utilize auditory stimuli have been designed to support users or patients with visual impairment that are incapable of using the conventional visual-based BCI. As an alternative to auditory P300-based BCI, researchers have reported the possibility of using the auditory steady state response (ASSR) in the binary-class BCI system. In the present work, we investigated the effect of selective attention on the amplitude of ASSRs when three ASSR stimuli are simultaneously given. The result shows that the amplitude of ASSR is significantly increased by approximately 20% when the subject selectively attend to the target stimulus. There is also no difference in the effect of selective attention between when two stimuli and three stimuli are given. This current work suggests the possibility of incooperating ASSR into the auditory BCI system that deal with multiple-class problem.

The aim of this study was to investigate the clinical features and clinical outcomes of T1 gallbladder (GB) cancer and to determine an appropriate surgical strategy for T1 GB cancer. A nationwide multicenter study, in which 16 University Hospitals in Korea participated, was performed from 1995 to 2004. A total of 258 patients, 117 patients with T1a and 141 patients with T1b disease were enrolled. Clinicopathologic findings and long-term follow-up results were analyzed after a consensus meeting of the Korean Pancreas Surgery Club was held. Simple cholecystectomy was performed in 95 patients (81.2 %) with T1a tumor and in 89 patients (63.1 %) with T1b tumor (p

Malignant tumors that metastasize to the pancreas are rare. Among them, renal cell carcinoma is the most common. Surgical resection is more effective in treatment for patients with pancreatic metastasis from renal cell carcinoma, although targeted therapy is applied, to advanced renal cell carcinoma. It is essential to know exact medical history of the patient, because metastasis can occur late after nephrectomy. Surgical procedure may vary, depending on location and number of tumors. We report a case of resection of a pancreatic head tumor, 20 years after nephrectomy due to renal cell carcinoma.

Purpose The aim of this study was to assess the awareness and practice of wound disinfection among Korean wound care nurses. Subjects and setting The target sample comprised 100 members of the Korea Wound Ostomy Continence Nurse Association. Seventy-eight wound care nurses responded to the questionnaire, yielding a response rate of 78%. Methods Potential respondents were contacted via e-mail and asked to complete a questionnaire designed for this study. Results Pressure ulcers were the most common wound type managed by WOC nurses, followed by surgical wounds. The mean score of items measuring awareness of wound disinfection practice and reported wound disinfection practice were 3.38 on a scale of 0 to 4 scale, and 3.14 on a scale of 0 to 4, respectively. Scores among items that queried awareness and practice in various methods for disinfecting a chronic wound disinfection were highest (3.74 and 3.67 out of 4, respectively) and scores of items querying disinfection with sodium hypochlorite were lowest (2.80 and 2.05 out of 4, respectively). There were significant differences between all items of awareness and reported practice except for disinfection with alcohol. Awareness of wound disinfection significantly correlated with reported practice. Conclusions Developing an effective educational program to enhance awareness is necessary to improve practice of wound disinfection.

In traditional brain-computer interface (BCI) studies, binary communication systems have generally been implemented using two mental tasks arbitrarily assigned to “yes” or “no” intentions (e.g., mental arithmetic calculation for “yes”). A recent pilot study performed with one paralyzed patient showed the possibility of a more intuitive paradigm for binary BCI communications, in which the patient’s internal yes/no intentions were directly decoded from functional near-infrared spectroscopy (fNIRS). We investigated whether such an “fNIRS-based direct intention decoding” paradigm can be reliably used for practical BCI communications. Eight healthy subjects participated in this study, and each participant was administered 70 disjunctive questions. Brain hemodynamic responses were recorded using a multichannel fNIRS device, while the participants were internally expressing “yes” or “no” intentions to each question. Different feature types, feature numbers, and time window sizes were tested to investigate optimal conditions for classifying the internal binary intentions. About 75% of the answers were correctly classified when the individual best feature set was employed (75.89% ± 1.39 and 74.08% ± 2.87 for oxygenated and deoxygenated hemoglobin responses, respectively), which was significantly higher than a random chance level (68.57% for p < 0.001). The kurtosis feature showed the highest mean classification accuracy among all feature types. The grand-averaged hemodynamic responses showed that wide brain regions are associated with the processing of binary implicit intentions. Our experimental results demonstrated that direct decoding of internal binary intention has the potential to be used for implementing more intuitive and user-friendly communication systems for patients with motor disabilities.

Virtual Reality (VR) is becoming popular and has been used in many kind of different purposes including entertainment, daily life activities and medical field. However, with the current VR technology, people are still be able to discriminate the VR from the real world very easily. Perhaps, the better way to develop the VR technology is not by considering how much VR looks like the real world but how much similar humans perceive from VR comparing to the real world. With this aspect, we perform experiments to show that the similarity in brain signal activity can be used as the measurement of the VR quality. We record EEG signals in occipital area of the brain and calculate the similarity between two signals obtained while the subject is observing VR objects and real world object. The results show that the similarity of EEG signal increases as the VR object becomes more similar to the real world object. This result suggests that the similarity of brain signal can be used as the measurement for VR quality.

Cationic antimicrobial peptides (AMPs) have attracted a great deal of interest as a promising candidate for a novel class of antibiotics that might effectively treat recalcitrant infections caused by a variety of microbes that are resistant to currently available drugs. However, the AMPs are inherently limited in that they are inevitably susceptible to attacks by proteases generated by human and pathogenic microbes; this vulnerability severely hinders their pharmaceutical use in human therapeutic protocols. In this study, we report that a halocidin-derived AMP, designated HG1, was found to be resistant to proteolytic degradation. As a result of its unique structural features, HG1 proved capable of preserving its antimicrobial activity after incubation with trypsin, chymotrypsin, and human matrix metalloprotease 7 (MMP-7). Additionally, HG1 was observed to exhibit profound antimicrobial activity in the presence of fluid from human skin wounds or proteins extracted from the culture supernatants of Staphylococcus aureus and Pseudomonas aeruginosa . Greater understanding of the structural motifs of HG1 required for its protease resistance might provide feasible ways to solve the problems intrinsic to the development of an AMP-based antibiotic.

Purpose We sought to determine the type and incidence of ostomy-related complications and identify associated factors in Korean ostomy patients. Methods A retrospective analysis of medical records of 1,170 patients who underwent end colostomy in Samsung Medical Center between October 1994 and February 2005 was completed. Complications were classified as stomal or peristomal. Stomal complications included bleeding, necrosis, mucocutaneous separation, prolapsed stoma, retracted stoma, and stenosis. Peristomal complications included varices, hernia, irritant contact dermatitis, allergic contact dermatitis, maceration, folliculitis, hyperplastic granulation, bacterial infection, candidal infection, malignancy in the peristomal area, mechanical damage, and pyoderma gangrenosum. A flat (flush) stoma was the most common stomal complication, occurring in 8.5% of subjects. Irritant contact dermatitis, occurring in 15.5%, was the most common peristomal complication. Gender and body mass index were associated with irritant contact dermatitis, hyperplasia, peristomal hernias, flat stomas, and retracted stomas. Conclusions Education for preventing irritant contact dermatitis, such as proper pouching and peristomal skin protection, and for weight control, should be emphasized in a self-care program for persons living with an ostomy. Preoperative marking by a WOC nurse is needed to reduce the prevalence of flat (flush) stomas.

There are scant studies that have analyzed the prognostic factors for malignant nonfunctioning endocrine tumors of the pancreas. We identified the predictive factors associated with long-term survival after surgical resection for malignant nonfunctioning endocrine tumors. Among the 25 patients seen at our hospital with a diagnosis of malignant nonfunctioning endocrine tumor, a review was performed on 22 of these patients who were surgically treated at our institution over the last 10 years. The following factors were evaluated for disease-specific mortality: age, gender, tumor location, tumor size, histological differentiation, status of the resection margin, and status of lymph node involvement. Tumor recurrence was noted in 9 cases (40.9%) among the 22 operated patients. Of the 9 recurrent cases, 7 patients (77.8%) had liver metastases. The median follow-up period was 24.8 (range: 3.7–121.4) months. The overall actuarial 1-, 2- and 5-year survival rates were 84.1%, 72.5%, and 52.8%, respectively. The factor shown to have a favorable independent prognostic significance was a negative resection margin (odds ratio = 19.44, 95% confidence interval = 1.22–310.54, P = 0.036). Definitive surgical resection of the primary tumor was a predictor of long-term survival after surgical resection for malignant nonfunctioning endocrine tumor.

EEG signals are vulnerable to several noise and artifacts occurred by muscle activities and body movements. Reducing these artifacts has been a challenge issue to design and develop a reliable mobile EEG system for various real-life applications including home entertainment as well as clinical monitoring, assessment and rehabilitation. In this paper, we describe a method for removing motion artifacts occurred by body movement using inertial sensors. The key contribution of this work is the automatic identification of independent components representing motion artifacts from EEG signals, incurring minimal computation in real-time. The experimental results from the application of the method show that it is able to remove, in real-time, the motion noise of body movement in an real-world environment with improving the quality of EEG signals up to 82% compared with recorded in seated condition.

Although pattern recognition studies have classified for upper limb movements, there is remaining issues for multi-finger movements. Depending on the user’s characteristic, usable movements for pattern recognition might be different. In addition, different finger movements might show similar surface electromyography (sEMG) from forearm and wrist. Therefore, we present a personalized protocol to select usable movements for each subject. Firstly, all movements were sorted into k classes using a k-means clustering method. Secondly, the movement, which showed different sEMG features for trials, was removed. 20 healthy subjects performed the 64 finger movements and 4 wrist movements. We found that the maximum number of classes (>95%) is different depending on the individual and location of electrodes; 18.5±3.0 on forearm and wrist, 11.7±1.9 on forearm, and 8.9±1.7 on wrist. The large standard deviation supports the personalized protocol for each subject in both locations.

Although human cognition often occurs while moving, most studies of the dynamics of the human brain examine subjects while static and seated in a highly controlled laboratory. EEG signals have been considered to be too noisy to record brain dynamics during human locomotion. Here, we present a real-time ambulatory brain computer interface which allows us to detect gait phases and remove motion-related artifacts from EEG signals during walking in real-world environments. We first construct stride-based artifact templates employing a gyroscope to measure the angular velocity of the human body. Then, we apply an adaptive Kalman filter to estimate the mapping between the stride-based artifact template and EEG space, subtracting the motion-related noise from the raw EEG signal. This study demonstrates the robustness of our system to remove gait-related movement artifacts during human locomotion. Experiments in real-world environments show the potential practicality of reallife applications of low-cost wearable and wireless BCI systems for users actively working in and interacting with their environments.

A computationally developed model of human upright balance control (Jo and Massaquoi on Biol cybern 91:188–202, 2004) has been enhanced to describe biped walking in the sagittal plane. The model incorporates (a) non-linear muscle mechanics having activation level -dependent impedance, (b) scheduled cerebrocerebellar interaction for control of center of mass position and trunk pitch angle, (c) rectangular pulse-like feedforward commands from a brainstem/ spinal pattern generator, and (d) segmental reflex modulation of muscular synergies to refine inter-joint coordination. The model can stand when muscles around the ankle are coactivated. When trigger signals activate, the model transitions from standing still to walking at 1.5 m/s. Simulated natural walking displays none of seven pathological gait features. The model can simulate different walking speeds by tuning the amplitude and frequency in spinal pattern generator. The walking is stable against forward and backward pushes of up to 70 and 75 N, respectively, and with sudden changes in trunk mass of up to 18%. The sensitivity of the model to changes in neural parameters and the predicted behavioral results of simulated neural system lesions are examined. The deficit gait simulations may be useful to support the functional and anatomical correspondences of the model. The model demonstrates that basic human-like walking can be achieved by a hierarchical structure of stabilized-long loop feedback and synergy-mediated feedforward controls. In particular, internal models of body dynamics are not required.

A recurrent integrator proportional integral derivative (PID) model that has been used to account for cerebrocerebellar stabilization and scaling of transcortical proprioceptive feedback in the control of horizontal planar arm movements has been augmented with long-loop force~feedback and gainscheduling to describe the control of human upright balance. The cerebellar component of the controller is represented by two sets of gains that each provide linear scaling of same-joint and interjoint long-loop stretch responses between ankle, knee, and hip. The cerebral component of the model includes a single set of same-joint linear force feedback gains. Responses to platform translations of a three-segment body model operating under this hybrid proprioception and force-based long-loop control were simulated. With low-velocity platform disturbances, ‘‘ankle-strategy’’-type postural recovery kinematics and electromyogram (EMG) patterns were generated using the first set of cerebeller control gains. With faster disturbances, balance was maintained by including the second set of gains cerebellar control gains that yielded ‘‘mixed ankle-hip strategy’’-type kinematics and EMG patterns. The addition of small amounts of simulated muscular coactivation improved the fit to certain human datasets. It is proposed that the cerebellum switches control gainsets as a function of sensed body kinematic state. Reduction of cerebellar gains with a compensatory increase in muscular stiffness yielded posture recovery with abnormal motions consistent with those found in cerebellar disease. The model demonstrates that stabilized hybrid long-loop feedback with scheduling of linear gains may afford realistic balance control in the absence of explicit internal dynamics models and suggests that the cerebellum and cerebral cortex may contribute to balance control by such a mechanism.

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (OGCs) is very rare, less than 1% of all pancreatic malignancies, and shows worse prognosis than that of invasive ductal adenocarcinoma of the pancreas. We present a case of en bloc resection for a huge undifferentiated carcinoma with OGCs that invaded the stomach and transverse mesocolon. A 67-year female was admitted for left upper quadrant pain and computed tomography demonstrated a mass occupying the lesser sac and abutting the stomach and pancreas. There were no distant metastases and the patient underwent subtotal pancreatectomy with splenectomy, total gastrectomy, and segmental resection of the transverse colon. Histopathological examination confirmed an 11 cm-sized undifferentiated carcinoma of the pancreas with OGCs. Immunohistochemical staining revealed reactivity with pan-cytokeratin in adenocarcinoma component, with vimentin in neoplastic multi-nucleated cells, with CD45/CD68 in OGCs, and with p53 in tumor cells, respectively. The patient had suffered from multiple bone metastases and survived 9 mo after surgery. This case supports the ductal epithelial origin of undifferentiated carcinoma with OGCs and early diagnosis could result in favorable surgical outcomes. Investigations on the surgical role and prognostic factors need to be warranted in this tumor.

This work addresses the development of a low-cost hybrid interface with eye tracking and brain signals. Eye movement detection is used for search task and EEG-based brain computer interface (BCI) for selection task. Multi-directional target selection experiments with the hybrid interface device were conducted with five subjects to evaluate the proposed hybrid interface scheme. The task asked each user to move a cursor onto a circular target among twelve possible positions and select it. Using the Fitts' law, the interface performance was compared with the computer mouse. With two BCI selection confirmation schemes, the hybrid interface attained 2-2.7 bit/s overall. Based on the results, the potential of the proposed hybrid interface was discussed.

This paper proposes the feasibility of a stiffness measurement for muscle contraction force estimation under muscle fatigue conditions. Bioelectric signals have been widely studied for the estimation of the contraction force for physical human-robot interactions, but the correlation between the biosignal and actual motion is decreased under fatigue conditions. Muscle stiffness could be a useful contraction force estimator under fatigue conditions because it measures the same physical quantity as the muscle contraction that generates the force. Electromyography (EMG), mechanomyography (MMG), and a piezoelectric resonance-based active muscle stiffness sensor were used to analyze the biceps brachii under isometric muscle fatigue conditions with reference force sensors at the end of the joint. Compared to EMG and MMG, the change in the stiffness signal was smaller (p < 0.05) in the invariable contraction force generation test until failure. In addition, in the various contraction level force generation tests, the stiffness signal under the fatigue condition changed

This paper describes a hybrid brain-computer interface (BCI) technique that combines the P300 potential, the steady state visually evoked potential (SSVEP), and event related de-synchronization (ERD) to solve a complicated multi-task problem consisting of humanoid robot navigation and control along with object recognition using a low-cost BCI system. Our approach enables subjects to control the navigation and exploration of a humanoid robot and recognize a desired object among candidates. This study aims to demonstrate the possibility of a hybrid BCI based on a low-cost system for a realistic and complex task. It also shows that the use of a simple image processing technique, combined with BCI, can further aid in making these complex tasks simpler. An experimental scenario is proposed in which a subject remotely controls a humanoid robot in a properly sized maze. The subject sees what the surrogate robot sees through visual feedback and can navigate the surrogate robot. While navigating, the robot encounters objects located in the maze. It then recognizes if the encountered object is of interest to the subject. The subject communicates with the robot through SSVEP and ERD-based BCIs to navigate and explore with the robot, and P300-based BCI to allow the surrogate robot recognize their favorites. Using several evaluation metrics, the performances of five subjects navigating the robot were quite comparable to manual keyboard control. During object recognition mode, favorite objects were successfully selected from two to four choices. Subjects conducted humanoid navigation and recognition tasks as if they embodied the robot. Analysis of the data supports the potential usefulness of the proposed hybrid BCI system for extended applications. This work presents an important implication for the future work that a hybridization of simple BCI protocols provide extended controllability to carry out complicated tasks even with a low-cost system.

Purpose: In spite of the recent improved results of hepatectomy for huge hepatocellular carcinomas (HCC), the prognosis of patients with huge HCCs is still poor compared to that of patients with small HCCs. This study was performed to compare the results of hepatectomy between patients with huge HCCs and those with small HCCs, to identify the prognostic factors in patients with huge HCCs, and to determine the preoperative selection criteria. Methods: We retrospectively analyzed 51 patients who underwent hepatectomy, between July 1994 and February 2009 at Dankook University Hospital. Patients with HCC≥10 cm were classified in large (L) group and others were classified in small (S) group. The clinicopathological features, operative procedures, and postoperative outcome were compared between both groups and various prognostic factors were investigated in group L. Results: Eleven patients were classified in group L. Tumor size, vascular invasion, and tumor stage were higher in group L. Postoperative morbidity was higher in group L, but mortality was not different between the groups. Disease-free survivals were significantly lower in group L than in group S (36.4%, and 24.2% vs. 72.0%, and 44.0% for 1- and 3-year), but overall survival rates were similar in both groups (45.5%, and 15.2% in group L vs. 60.3%, and 41.3% in group S for 3- and 5-year). Presence of satellite nodules was the only prognostic factor in multivariate analysis after surgery for huge HCC. Conclusion: Regardless of tumor size, huge HCCs deserve consideration for surgery in patients with preserved liver function. Furthermore, the effect of surgery could be maximized with appropriate selection criteria, such as huge HCC without satellite nodules.

This work presents that, only using non-invasively captured brain signals, a person can navigate an electric wheelchair with no serious training for a long term. Only two electrodes are set on the scalp non-invasively to detect a P300 EEG signal and a reference signal. A simple signal processing interprets the measured signals to decide a movement direction of the wheelchair. The whole devices are loaded on the wheelchair. No external system is required. The experimental results demonstrate the feasibility of the simple BCI processing to achieve reasonable performance.

Background Because intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is believed to show a better clinical course than non-papillary biliary neoplasms, it is important to make a precise diagnosis and to perform complete surgical resection. Case presentation We herein report a case of malignant IPMN-B treated by right trisectionectomy with caudate lobectomy and extrahepatic bile duct resection. Radiologic images showed marked dilatation of the left medial sectional bile duct (B4) resulting in a bulky cystic mass with multiple internal papillary projections. Duodenal endoscopic examination demonstrated very patulous ampullary orifice with mucin expulsion and endoscopic retrograde cholangiogram confirmed marked cystic dilatation of B4 with luminal filling defects. These findings suggested IPMN-B with malignancy potential. The functional volume of the left lateral section was estimated to be 45%. A planned extensive surgery was successfully performed. The remnant bile ducts were also dilated but had no macroscopic intraluminal tumorous lesion. The histopathological examination yielded the diagnosis of mucin-producing oncocytic intraductal papillary carcinoma of the bile duct with poorly differentiated carcinomas showing neuroendocrine differentiation. The tumor was 14.0 × 13.0 cm-sized and revealed no stromal invasiveness. Resection margins of the proximal bile duct and hepatic parenchyma were free of tumor cell. The patient showed no postoperative complication and was discharged on 10th postoperative date. He has been regularly followed at outpatient department with no evidence of recurrence. Conclusion Considering a favorable prognosis of IPMN-B compared to non-papillary biliary neoplasms, this tumor can be a good indication for aggressive surgical resection regardless of its tumor size.

Human gaits in a sagittal plane are simulated throughout a musculoskeletal model with a simple feedback postural controller. Hill-type muscletendon models generate joint motions over each leg. Typical human gait data about joint torques and angles is used to estimate muscular activation signal profiles by a simple optimization technique. A simple feedback controller updates the activation profiles to achieve stable dynamical walking simulation through optimization with a genetic algorithm. Simulation study demonstrates the proposed approach achieves realistic human walking behavior with neurophysiologically plausible muscular activations.