Search

The commercialisation of virtual reality (VR) headsets has made them more affordable and popular in gaming and entertainment. The natural interaction between the VR environment and users can maximise immersion and is crucial to VR gaming. Despite their growing popularity, educational VR games prioritise learning over immersion and require users to learn to interact with and play games using tutorials. Herein, we developed a game named Numverse with an accompanying tutorial. After selecting the tutorial content, we programmed the user interface and proposed a delivery method for the tutorial. We evaluated the user experience based on the effects of the presence or absence of the tutorial and its mode of delivery. The tutorials were of three types: no tutorial, instruction-screen tutorial, and context-sensitive tutorial, with the latter being the most preferred. The evaluation results show that presence, ability to learn controls, intrinsic motivation, and learning effectiveness are higher for the instruction-screen and context-sensitive tutorials than for no tutorial. On average, users experienced more motion sickness in the no-tutorial case, with a significant difference in nausea items. This study asserts the importance of tutorials in VR games, and its findings could improve user experience in future VR games. [ABSTRACT FROM AUTHOR]

This study aims to understand the usability of common button colours and background choices in the existing augmented reality (AR) interface. AR is increasingly used in dynamic situations, such as driving using an AR head-up display. However, studies regarding the usability of AR interfaces, especially about the colours, are scarce. Twenty-four participants performed button selection tasks in an experiment using Microsoft HoloLens. Three measures (task completion time, the number of errors, and button colour visibility were collected for the 12 experimental conditions (3 backgrounds by 4 button colours). Significant differences were found in completion time between backgrounds and blue button visibility. On a moving background, the most effective button colour is orange, and the most minor effective button colour is blue. The results of this study can be used for colour choices in designing AR applications and devices. [ABSTRACT FROM AUTHOR]

As VR technology advances and network speeds rise, social VR platforms are gaining traction. These platforms enable multiple users to socialize and collaborate within a shared virtual environment using avatars. Virtual reality, with its ability to augment visual information, offers distinct advantages for collaboration over traditional methods. Prior research has shown that merely sharing another person's viewpoint can significantly boost collaborative efficiency. This paper presents an innovative non-verbal communication technique designed to enhance the sharing of visual information. By employing virtual cameras, our method captures where participants are focusing and what they are interacting with, then displays these data above their avatars. The direction of the virtual camera is automatically controlled by considering the user's gaze direction, the position of the object the user is interacting with, and the positions of other objects around that object. The automatic adjustment of these virtual cameras and the display of captured images are symmetrically conducted for all participants engaged in the virtual environment. This approach is especially beneficial in collaborative settings, where multiple users work together on a shared structure of multiple objects. We validated the effectiveness of our proposed technique through an experiment with 20 participants tasked with collaboratively building structures using block assembly. [ABSTRACT FROM AUTHOR]

The rapid growth of the mHealth market has led to the development of several tools to evaluate user experience. However, there is a lack of universal tools specifically designed for this emerging technology. This study was conducted with the aim of developing and verifying a user experience evaluation scale for mHealth apps based on factors proposed in previous research. The initial draft of the tool was created following a comprehensive review of existing questionnaires related to mHealth app evaluation. The validity of this scale was then tested through exploratory and confirmatory factor analysis. The results of the factor analysis led to the derivation of 16 items, which were conceptually mapped to five factors: ease of use and satisfaction, information architecture, usefulness, ease of information, and aesthetics. A case study was also conducted to improve mHealth apps concerning personal health records using this scale. In conclusion, the developed user experience evaluation scale for mHealth apps can provide comprehensive user feedback and contribute to the improvement of these apps. [ABSTRACT FROM AUTHOR]

Digital clusters have been adopted as displays in vehicles, and various driving information is presented through the digital clusters with different colors. However, drivers with color vision deficiency (CVD) face difficulties in recognizing the information conveyed through color, which might lead to serious traffic accidents. In this paper, the usability of symbols in automobile digital clusters was evaluated from the perspective of people with CVD, and alternative designs were proposed and validated to improve recognition of the symbols. Twenty-seven participants with CVD and twenty-one participants with normal color vision (NCV) were recruited to investigate the influence of design elements, such as symbol color, stroke width, cluster background color, and adjacent symbol color. The choice reaction time and error rate were measured, and the perceived importance and visibility were collected using a questionnaire. As a result, the following four effects of symbol designs on the usability and recognition were identified: (1) if the existing color profile for symbols is applied, the symbol recognition was improved by modifying symbol design elements (e.g., stroke width); (2) For the symbol stroke width, a stroke width-to-height ratio of 0.12 or more was recommended; (3) Gray color is recommended for the background color, but lighting a red symbol on a gray background should be avoided for the participants with CVD; (4) When presenting a symbol adjacent to another one, presenting in red-red, green-green, orange-red, and orange-green combinations should be avoided. The results of this study can be used as reference materials when developing vehicle display interfaces that are accessible to all users including people with CVD. [ABSTRACT FROM AUTHOR]

The demand for healthcare services using mobile devices has surged owing to the ageing population and increasing interest in personal healthcare. In particular, extensive efforts have been made to utilise mobile personal health records (PHRs) to provide personalised healthcare services to users (patients). Users must understand various types of health information that are included in PHRs to ensure successful and continued use of mobile PHRs. In this study, we developed and evaluated a user-friendly method for delivering health information from a PHR using mobile devices with small screens. We first constructed a patient journey map (PJM) for easy verification of disease treatment data from the perspective of the patient. Subsequently, we developed a mobile prototype that organises and visualises personal health information according to the patient-centred PJM and conducted user evaluations with 20 Korean participants. The results demonstrated that information delivery using the proposed prototype was easy to understand, user-friendly, and efficient. This paper highlights the importance of PJMs for patients in the understanding and use of different medical information. The proposed method is expected to promote the development of patient-centred mobile health applications in the future. [ABSTRACT FROM AUTHOR]

We sought to understand how the perception of personal space is influenced by different levels of social density, spatial density, and type of window-view in South Korean and United Kingdom workplaces. We employed virtual reality to simulate shared and single occupancy offices. We obtained personal space estimations using a virtual disc around the participant which could be extended and retracted, inside the simulation, to indicate perceived amount of personal space, and compared this measure to questionnaire-based estimations. We found that in both cultures participants experienced greater perceived personal space (1) when in a sparse rather than dense office and (2) having a view of the city outside the office. However, British, but not Korean, participants had significantly higher personal space estimations in single occupancy offices than in shared offices. These results suggest subtle cross-cultural differences in workplace experience, that could only be investigated using virtual reality. [ABSTRACT FROM AUTHOR]

Owing to technological advancements, kiosks have become more prevalent in public places. When using such kiosks, elderly persons and people with disabilities face problems related to accessibility and usability, such as difficulties in kiosk operations such as menu selection and in accessing the kiosk space. Previous studies have usually included accessibility as a subset of usability. However, in this study, we aim to redefine the relationship between these two concepts with a focus on newly emerging kiosk devices. First, we performed a literature review to thoroughly analyze these concepts. Then, we conducted a focus group interview (FGI) targeting people with visual, hearing, and physical impairments to learn about the difficulties that these people face when using kiosks. Finally, we analyzed the characteristics of accessibility and usability related to kiosks and designed a diagram that illustrated the relationship between them. While accessibility and usability shared similarities regarding consistency and user control, they differed deeply regarding their subcategory items; many opinions on accessibility were related to essential functions, whereas many on usability were related to psychological factors such as additional functions or personal preferences. These results can be useful when creating laws and guidelines regarding the accessibility and usability of kiosks or when developing kiosk functions. [ABSTRACT FROM AUTHOR]

Augmented reality (AR) technologies are becoming increasingly popular. However, studies regarding the usability of AR interfaces are scarce. This study aims to derive the optimal usability design of the AR interface by analyzing the performance of 12 interface conditions (2 button sizes × 3 distances × 2 interaction types). An experiment was conducted using Microsoft HoloLens, in which participants performed button selection tasks with an array of 3 × 3 virtual buttons. The task completion time and the number of errors were measured along with a subjective satisfaction score. The results showed that a clicker-based interaction was more effective in task completion time, the number of errors and user satisfaction than a hand gesture. Furthermore, large buttons required a significantly shorter task completion time than small buttons. There was no significant difference in the number of errors between the two sizes. A distance of at least 80 cm from the eye to the virtual object is most favorable for a good performance. There was a significant difference in the task completion times between 40 cm and 80 cm and between 40 cm and 120 cm. These results can aid the interface designs for AR applications and devices. [ABSTRACT FROM AUTHOR]

Meal-assistance robots (MARs) help feed meals to users with disabilities or who need help consuming their meals. Although such MARs have been introduced in various fields, guidelines for evaluating MARs are limited. This study aims to develop comprehensive guidelines to assess the user experience (UX) of MAR designs considering its social interaction characteristics between humans and robots. Participants from three groups (patients, doctors, and caregivers) with different perspectives on MARs were recruited and a focus group interview was conducted to collect their UXs with MARs. The three groups showed different UXs with MARs in user interface design, robot arm motion, and safety and mobility. In addition, based on the literature review, eight UX features (usability, emotion, value, naturalness, assistance, acceptance, personality, and culture) are proposed to evaluate MAR interfaces. The proposed comprehensive design guideline will be particularly useful in evaluating and designing the UX of MARs. [ABSTRACT FROM AUTHOR]

This study assessed the intra‐acquirer, intra‐ and inter‐processor reliability, and validity of the in vivo assessment of the medial gastrocnemius (MG), lateral gastrocnemius (LG) and soleus (SOL) muscle volumes using freehand 3D ultrasound (3DUS) in typically developing infants. Reliability assessments of freehand 3DUS were undertaken in infants across three ages groups: three, six and twelve months of age, with validity testing completed against magnetic resonance imaging (MRI) in infants at 3 months of age. Freehand 3DUS scanning was carried out by a single acquirer, with two independent processors manually segmenting images to render volumes. MRI images were segmented independently by a separate processor, with the volumes compared to those obtained via freehand 3DUS. Reliability was assessed using intraclass correlation (ICC), coefficient of variance (CV) and minimal detectable change (MDC) across each assessment time point. Validity was assessed using the limits of agreement. ICCs for intra‐acquirer reliability of the acquisition process for freehand 3DUS ranged from 0.91 to 0.99 across all muscles. ICCs for intra‐processor and inter‐processor reliability for the segmentation process of freehand 3DUS ranged from 0.80 to 0.98 across all muscles. Acceptable levels of agreement between muscle volume obtained by freehand 3DUS and MRI were found for all muscles; however, freehand 3DUS overestimated muscle volume of MG and LG and underestimate the SOL compared with MRI, with average absolute differences of MG = 0.3 ml, LG = 0.3 ml and Sol = 1.2 ml. Freehand 3DUS is a reliable method for measuring in vivo triceps surae muscle volume in typically developing infants. We conclude that freehand 3DUS is a useful tool to assess changes in muscle volume in response to growth and interventions in infants. [ABSTRACT FROM AUTHOR]

Although new virtual reality (VR) devices and their contents are actively being released, there are still not enough studies to prepare its interface/interaction standard. In this study, it was investigated whether specific interaction factors influenced task performance and the degree of virtual reality sickness when performing pointing tasks in immersive virtual reality. A smartphone-based VR device was used, and twenty-five targets were placed in a 5 × 5 layout on the VR experimental area that extended to a range similar to the human viewing angle. Task completion time (TCT) was significantly affected by target selection method (p < 0.001) and target size (p < 0.001), whereas the error rate (ER) significantly differed for the target selection method (p < 0.001) and not for the target size (p = 0.057). Target location was observed to be a factor affecting TCT (p < 0.001), but it did not affect the ER (p = 0.876). VR sickness was more severe when the target size was smaller. Gaze selection was found to be more efficient when accuracy is demanded, and manual selection is more efficient for quick selection. Moreover, applying these experimental data to Fitts' Law showed that the movement time was found to be less affected by the device when using the gaze-selection method. Virtual reality provides a three-dimensional visual environment, but a one-dimensional formula can sufficiently predict the movement time. The result of this study is expected to be a reference for preparing interface/interaction design standards for virtual reality. [ABSTRACT FROM AUTHOR]

Purpose: Diffuse optical tomography breast imaging system (DOTBIS) non-invasively measures tissue concentration of hemoglobin, which is a potential biomarker of short-term response to neoadjuvant chemotherapy. We evaluated whether DOTBIS-derived measurements are modifiable with targeted therapies, including AKT inhibition and endocrine therapy. Methods: We conducted a proof of principle study in seven postmenopausal women with stage I-III breast cancer who were enrolled in pre-surgical studies of the AKT inhibitor MK-2206 (n = 4) or the aromatase inhibitors exemestane (n = 2) and letrozole (n = 1). We performed DOTBIS at baseline (before initiation of therapy) and post-therapy in the affected breast (tumor volume) and contralateral, unaffected breast, and measured tissue concentrations (in μM) of total hemoglobin (ctTHb), oxyhemoglobin (ctO2Hb), and deoxyhemoglobin (ctHHb), as well as water fraction (%). Results: We found consistent decreases in DOTBIS-measured hemoglobin concentrations in tumor volume, with median percent changes for ctTHb, ctHHb, ctO2Hb, and water fraction for the entire cohort of − 27.1% (interquartile range [IQR] 37.5%), − 49.8% (IQR 29.3%), − 33.5% (IQR 47.4%), and − 3.6% (IQR 10.6%), respectively. In the contralateral breast, median percent changes for ctTHb, ctHHb, ctO2Hb, and water fraction were + 1.8% (IQR 26.7%), − 8.6% (IQR 29.3%), + 6.2% (IQR 29.5%), and + 1.9% (IQR 30.7%), respectively. Conclusion: We demonstrated that DOTBIS-derived measurements are modifiable with pre-surgical AKT inhibition and endocrine therapy, supporting further investigation of DOTBIS as a potential imaging assessment of response to neoadjuvant targeted therapies in early stage breast cancer. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study is to evaluate whether the changes in optically derived parameters acquired with a diffuse optical tomography breast imager system (DOTBIS) in the contralateral non-tumor-bearing breast in patients administered neoadjuvant chemotherapy (NAC) for breast cancer are associated with pathologic complete response (pCR).Methods: In this retrospective evaluation of 105 patients with stage II-III breast cancer, oxy-hemoglobin (ctO2Hb) from the contralateral non-tumor-bearing breast was collected and analyzed at different time points during NAC. The earliest monitoring imaging time point was after 2-3 weeks receiving taxane. Longitudinal data were analyzed using linear mixed-effects modeling to evaluate the contralateral breast ctO2Hb changes across chemotherapy when corrected for pCR status, age, and BMI.Results: Patients who achieved pCR to NAC had an overall decrease of 3.88 μM for ctO2Hb (95% CI, 1.39 to 6.37 μM), p = .004, after 2-3 weeks. On the other hand, non-pCR subjects had a non-significant mean reduction of 0.14 μM (95% CI, - 1.30 to 1.58 μM), p > .05. Mixed-effect model results indicated a statistically significant negative relationship of ctO2Hb levels with BMI and age.Conclusions: This study demonstrates that the contralateral normal breast tissue assessed by DOTBIS is modifiable after NAC, with changes associated with pCR after only 2-3 weeks of chemotherapy. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) is becoming increasingly prevalent in all spheres of society. Still, the perception of AI from users and customers remains the main barrier for its widespread adoption. Previous studies showed that the acceptance of new technologies in society depends on perceived characteristics. This study examined users' perception of trust, the difficulty of the task, and application performance when using an AI‐based technology. These factors help us to elucidate the mechanisms for building trust in AI technology from the users' perspective. A total of 18 participants took part in the experiment with the Google AutoDraw software as an AI tool. As a result, the difficulty of the task, perceived performance, and success/failure of the task can be regarded as the influential factors for the perceived trust evaluation. The perceived trust of users in new AI products would be increased by improving product performance and the successful implementation of the tasks. The obtained results and insights can serve AI product developers to increase the level of users' trust and attraction towards their technologies and applications. [ABSTRACT FROM AUTHOR]

In this work, we investigated the change in tumor microenvironment caused by semi-ablative high-dose irradiation and its implication on tumor cell survival, reoxygenation of hypoxic cells and repopulation in FSaII tumors grown subcutaneously in the hind legs of C3H mice. Tumors were exposed to 10–30 Gy of X-ray radiation in a single exposure, and the vascularity and blood perfusion were assessed based on the levels of CD31 expression and Hoechst 33342 perfusion, respectively. The tumor hypoxia was assessed by staining for pimonidazole adduct formation and the expression of hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase 9 (CA9). Tumor cell survival was determined using in vivo-in vitro excision assay method. The proportion of hypoxic cells in the tumor was determined from the surviving cell fraction in tumors exposed to a test dose under aerobic and hypoxic conditions. Radiation expsoure markedly reduced the functional vascularity and blood perfusion, and profoundly increased the expression of HIF-1α and CA9 pointing to an increase in tumor hypoxia. The overall clonogenic cell survival progressively decreased during 2–5 days postirradiation, most likely due to the radiation-induced vascular dysfunction. In turn, the proportion of surviving hypoxic cells decreased over several days postirradiation, presumably due to reoxygenation of hypoxic cells. The oxygen supplied through small fractions of blood vessels that survived the high-dose exposure, together with a reduction of oxygen consumption due to massive cell death, appeared to be the cause of the reoxygenation of hypoxic cells. The surviving tumor cells then subsequently repopulated. The findings from this study using a murine tumor model suggest that the efficacy of stereotactic body radiotherapy (SBRT) and stereotactic radiosurgery (SRS) may be significantly improved by allowing an inter-fraction time for reoxygenation while avoiding repopulation. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) devices have recently become popular; however, research on input methods for VR devices is lacking. The main input methods of current commercial devices can be classified into two categories: manual selection using a controller and gaze selection. This study aims to derive the optimal input method and timing for VR devices by analyzing the performance of these input methods. A study is conducted in which participants wear a VR headset and select an activated input button from a 3 × 3 array on a VR device with two button sizes and two input methods. The manual selection method exhibits a shorter task completion time but a greater error number compared to the gaze selection method. For the gaze selection method, the task completion time and target search time were shortest when the gaze timing was 1 s. Further, the button size was determined to be statistically significant only when the manual selection method was used. The results of this study can be used as a reference in future VR user experience and product design. [ABSTRACT FROM AUTHOR]

Aim: To test a hypothetical path model evaluating the influence of menopause symptoms on sexual function among middle‐aged perimenopausal women, as well as identify the mediating roles of body image, depression and sexual communication in this relationship. Methods: We used a cross‐sectional, correlational design. We included one exogenous variable (menopause symptoms) and four endogenous variables (body image, depression, sexual communication and sexual function) in the proposed model. All data were collected between January 19 and March 11, 2016, and analyzed using spss statistics 25.0 and AMOS 23.0. Results: Eight of the nine hypothesized paths in the model were significant. Specifically, menopause symptoms were significantly associated with sexual function via the effects of body image, depression and sexual communication. Conclusion: This study may provide basic data for counseling and nursing programs to help improve sexual function in middle‐aged perimenopausal women. Particularly, these programs should focus on the indirect paths via body image, depression and sexual communication, such as by improving body image and sexual communication and reducing depression. [ABSTRACT FROM AUTHOR]

Background/Objectives Infantile hemangiomas ( IHs) are vascular tumors with the potential for significant morbidity. There is a lack of validated objective tools to assess IH severity and response to treatment. Diffuse optical spectroscopy ( DOS), a noninvasive, nonionizing imaging modality, can measure total hemoglobin concentration and hemoglobin oxygen saturation in tissue to assess IH vascularity and response to treatment. Our objective was to evaluate the utility of a wireless, handheld DOS system to assess IH characteristics at selected points during their clinical course. Methods Thirteen subjects (initial age 5.8 ± 2.0 mos) with 15 IHs were enrolled. IHs were classified as proliferative, plateau phase, or involuting. Nine patients with 11 IHs were untreated; four patients with 4 IHs were treated with timolol or propranolol. Each IH was evaluated by placing the DOS system directly on the lesion as well a normal contralateral skin site. IH vascularity and oxygenation were scored using a newly defined normalized hypoxia fraction ( NHF) coefficient. Measurements were recorded at various intervals from the initial visit to 1 to 2 years of age. Results For the nine untreated IHs, the NHF was highest at 6 months of age, during proliferation. Differences in NHFs between the proliferation and the plateau (p = 0.02) and involuting (p < 0.001) stages were statistically significant. In treated patients, the NHF normalized to 60% after 2 months. One treated IH came within 5% of the NHF for normal skin after 12 months. Conclusions DOS can be used to assess the vascularity and tissue oxygenation of IHs and monitor their progression and response to treatment. [ABSTRACT FROM AUTHOR]

Many people have significant difficulties while using information technology (IT) devices. This study suggests a new concept of IT interaction disability (ITID) to understand the significant difficulties that users may encounter while using IT devices. The task, interface, and context (TIC) framework for classifying the types of ITID is also developed; this framework includes three components: tasks, user interface elements, and context factors. A case study in which visually impaired people used smartphones was conducted to illustrate the types of ITID and to show the applicability of the TIC framework. The result of this study can provide insights to researchers to improve the understanding of the significant difficulties of using IT devices and to analyse these difficulties systematically. [ABSTRACT FROM PUBLISHER]

While interacting with a product or a service, people have diverse experiences, which constitute user experience (UX). In this study, the hierarchical dimensions of UX were considered, including overall UX, its elements (usability, affect, and user value) and their subelements. To determine how UX changes over time, the temporal changes of the influence of each element and subelement were analyzed. Twenty subjects participated in a longitudinal experiment by using a social network service (SNS). The most important element of UX changed from usability to user value after one week of use. These results suggest that adoption of an SNS occurs in two phases: a phase of affected by usability and a phase affected by user value. Identification of these phases and the systematic approach used in the study are expected to contribute to design and evaluation of new SNSs and other products and services. [ABSTRACT FROM AUTHOR]

User experience has become a major issue lately with user value as one of its key elements. This study proposes a method to evaluate user value using a questionnaire specialized for a mobile device such as smartphones. The questionnaire was developed considering elements of user value, product features, and context of use. Then, a case study with hundreds of participants was conducted via the Internet to verify and screen out questionnaire items in terms of reliability and validity. Finally, a total of 16 questionnaire items were selected for evaluating elements of user value, consisting of self-satisfaction, pleasure, sociability, customer need, and attachment. The results of this study are expected to help understand potential users and select design alternatives. [ABSTRACT FROM AUTHOR]

Diffuse optical tomography (DOT) is a noninvasive, nonionizing imaging modality that uses near-infrared light to visualize optically relevant chromophores. A recently developed dynamic DOT imaging system enables the study of hemodynamic effects in the breast during a breath-hold. Dynamic DOT imaging was performed in a total of 21 subjects (age 54 ± 10 years) including 3 healthy subjects and 18 subjects with benign (n = 8) and malignant (n = 14) masses. Three-dimensional time-series images of the percentage change in oxygenated and deoxygenated hemoglobin concentrations ([HbO2] and [Hb]) from baseline are obtained over the course of a breath-hold. At a time point of 15 s following the end of the breath-hold, [Hb] in healthy breasts has returned to near-baseline values (1.6% ± 0.5%), while tumor-bearing breasts have increased levels of [Hb] (6.8% ± 3.6%, p < 0.01). Further, healthy subjects have a higher correlation between the breasts over the course of the breath-hold as compared with the subjects with breast cancer (healthy: 0.96 ± 0.02; benign: 0.89 ± 0.02; malignant: 0.78 ± 0.23, p < 0.05). Therefore this study shows that dynamic features extracted from DOT measurements can differentiate healthy and diseased breast tissues. These features provide a physiologic method for identifying breast cancer without the need for ionizing radiation. [ABSTRACT FROM AUTHOR]

The term user experience (UX) encompasses the concepts of usability and affective engineering. However, UX has not been defined clearly. In this study, a literature survey, user interview and indirect observation were conducted to develop definitions of UX and its elements. A literature survey investigated 127 articles that were considered to be helpful to define the concept of UX. An in-depth interview targeted 14 hands-on workers in the Korean mobile phone industry. An indirect observation captured daily experiences of eight end-users with mobile phones. This study collected various views on UX from academia, industry, and end-users using these three approaches. As a result, this article proposes definitions of UX and its elements: usability, affect, and user value. These results are expected to help design products or services with greater levels of UX. © 2011 Wiley Periodicals, Inc. This article was published online on 20 October 2011. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 13 June 2013. [ABSTRACT FROM AUTHOR]

The levels of persistent organic pollutants (POPs) were determined in 50 samples of Korean human milk. POPs include organochlorine pesticides (OCPs) [aldrin, chlordanes, dieldrin, dichlorodiphenyltrichloroethanes (DDTs), endrins, heptachlors, hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), mirex, and toxaphenes] and marker PCBs (PCB28, PCB52, PCB101, PCB138, PCB153 and PCB180). In all samples, p,p′-DDE were determined as 75.5–1115.3 ng/g fat. The compounds β-HCH and p,p’-DDT were detected at 72% and 60% of the samples, respectively. Chlordanes (nd–84.9 ng/g fat) heptachlors (nd–40.1 ng/g fat), HCB (nd–42.9 ng/g fat) and PCBs (nd–38.3 ng/g fat) were detected in several samples. The ratio of dichlorodiphenyltrichloroethylene (DDE)/DDT was 6.8, which explained that exposure of volunteers to DDT did not occur recently. Compared with the previous monitoring data, the level of marker PCBs generally decreased in the milk samples. The levels of OCPs are significantly correlated to the residential periods of the mothers but not with their dietary habits. Considering the daily intake of each OCPs, 18% of infants would ingest the amount of heptachlor exceeding the acceptable daily intake (ADI) proposed by World Health Organization (WHO). There was no sample surpassing the WHO ADI for DDTs, HCB and chlordanes. [ABSTRACT FROM PUBLISHER]

Hepatocellular carcinoma (HCC) is one of the most frequent malignant tumors in the world. The only serological marker widely used for the diagnosis of HCC is alpha-fetoprotein (AFP). Despite that AFP is widely used for the diagnosis of HCC, it has a limit as a serological marker due to its low sensitivity and specificity. The human cervical cancer proto-oncogene 1 (HCCR-1) was previously reported as a new biomarker for HCC. To further evaluate the HCCR-1 as a biomarker for HCC, we conducted the prospective cohort study. We evaluated the significance of simultaneous measurement of 2 tumor markers in the diagnosis of HCC in China, Japan and Korea. Two markers for HCC, AFP and HCCR-1, were measured in the sera obtained from 1,338 patients at the time of initial diagnosis of HCC. Of the 1338 HCC patients, 616 (46%) and 686 (51.3%) were sero-positive for AFP and HCCR-1, respectively. The positive rate for HCC was increased up to 74.1% in combined use of AFP and HCCR-1. Many cases (54%) for AFP-negative HCC were positive for HCCR-1 and vice versa. More importantly, the diagnostic rate for small HCC (< 2 cm) was significantly improved in the combined analysis of AFP and HCCR-1 to 56.9% although it was only 40.1% and 23.4% in the single analysis of HCCR-1 and AFP, respectively. Our result suggests that the HCCR-1 could be an useful biomarker for HCC while the diagnostic rate could be significantly improved in the combined use of HCCR-1 and AFP. [ABSTRACT FROM AUTHOR]

Purpose: The presence of two or more epileptogenic pathologies in patients with epilepsy is often observed, and the coexistence of focal cortical dysplasia (FCD) with hippocampal sclerosis (HS) is one of the most frequent clinical presentations. Although surgical resection has been an important treatment for patients with refractory epilepsy associated with FCD, there are few studies on the surgical treatment of FCD accompanied by HS, and treatment by resection of both neocortical dysplastic tissue and hippocampus is still controversial. Methods: We retrospectively recruited epilepsy patients who had undergone surgical treatment for refractory epilepsy with the pathologic diagnosis of FCD and the radiologic evidence of HS. We evaluated the prognostic roles of clinical factors, various diagnostic modalities, surgical procedures, and the severity of pathology. Results: A total of 40 patients were included, and only 35.0% of patients became seizure free. Complete resection of the epileptogenic area (p = 0.02), and the presence of dysmorphic neurons or balloon cells on histopathology (p = 0.01) were associated with favorable surgical outcomes. Patients who underwent hippocampal resection were more likely to have a favorable surgical outcome (p = 0.02). Conclusions: We show that patients with complete resection of epileptogenic area, the presence of dysmorphic neurons or balloon cells on histopathology, or resection of hippocampus have a higher chance of a favorable surgical outcome. We believe that this observation is useful in planning of surgical procedures and predicting the prognoses of individual patients with FCD patients accompanied by HS. [ABSTRACT FROM AUTHOR]

The human arm exhibits outstanding manipulability in executing various tasks by taking advantage of its intrinsic compliance, force sensation, and tactile contact clues. By examining human strategy in controlling arm impedance, we may be able to understand underlying human motor control and develop control methods for dexterous robotic manipulation. This paper presents a novel method for estimating multijoint stiffness by using electromyogram (EMG) and an artificial neural network model. The artificial network model developed in this paper relates EMG data and joint motion data to joint stiffness. With the proposed method, the multijoint stiffness of the arm was estimated without complex calculation or specialized apparatus. The feasibility of the proposed method was confirmed through experimental and simulation results. [ABSTRACT FROM AUTHOR]

Current demonstrations of brain-machine interfaces (BMIs) have shown the potential for controlling neuroprostheses under pure motion control. For interaction with objects, however, pure motion control lacks the information required for versatile manipulation. This paper investigates the idea of applying impedance control in a BMI system. An extraction algorithm incorporating a musculoskeletal arm model was developed for this purpose. The new algorithm, called the muscle activation method (MAM), was tested on cortical recordings from a behaving monkey. The MAM was found to predict motion parameters with as much accuracy as a linear filter. Furthermore, it successfully predicted limb interactions with novel force fields, which is a new and significant capability lacking in other algorithms. [ABSTRACT FROM AUTHOR]

Research on brain-machine interfaces (BMI's) is directed toward enabling paralyzed individuals to manipulate their environment through slave robots. Even for able-bodied individuals, using a robot to reach and grasp objects in unstructured environments can be a difficult telemanipulation task. Controlling the slave directly with neural signals instead of a hand-master adds further challenges, such as uncertainty about the intended trajectory coupled with a low update rate for the command signal. To address these challenges, a continuous shared control (CSC) paradigm is introduced for BMI where robot sensors produce reflex-like reactions to augment brain-controlled trajectories. To test the merits of this approach, CSC was implemented on a 3-degree-of-freedom robot with a gripper bearing three co-located range sensors. The robot was commanded to follow eighty-three reach-and-grasp trajectories estimated previously from the out- puts of a population of neurons recorded from the brain of a monkey. Five different levels of sensor-based reflexes were tested. Weighting brain commands 70% and sensor commands 30% produced the best task performance, better than brain signals alone by more than seven-fold. Such a marked performance improvement in this test case suggests that some level of machine autonomy will be an important component of successful BMI systems in general. [ABSTRACT FROM AUTHOR]

15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) was initially identified as a high affinity natural ligand for the peroxisome proliferator-activated receptor (PPAR)-γ. Recent studies have shown that it has a potent anti-inflammatory effect by attenuating the expression of proinflammatory mediators in activated macrophages, mainly through the inhibition of nuclear factor (NF)-κB-dependent transcription of inflammatory genes. In this study, we investigated the synergistic effect of 15d-PGJ2 on the expression of LPS-induced chemokine KC mRNA in mouse peritoneal macrophages. The time course of KC mRNA expression in cells stimulated with 15d-PGJ2 plus LPS simultaneously (15d-PGJ2/LPS) showed similar patterns to the cells treated with LPS alone, and 15d-PGJ2 had no effect on the stability of LPS-induced KC mRNA expression. Although NF-κB activity in cells treated with LPS was augmented by 15d-PGJ2, pyrrolidone dithiocarbamate (PDTC) did not block the synergistic effect of 15d-PGJ2 on LPS-induced KC mRNA expression. However, the synergistic effect of 15d-PGJ2 was markedly inhibited when the macrophages were treated with a inhibitor of the mitogen-activated protein kinase (MAPK) signalling pathway, 2′-amino-3′-methoxyflavine (PD98059). Therefore, the mechanism of synergistic action of 15d-PGJ2 on the expression of LPS-induced KC mRNA in mouse peritoneal macrophages is possibly related to the MAPK signalling pathway, not to NF-κB activation. These data may contribute to unravelling some of the different mechanisms contrary to the anti-inflammatory effect of 15d-PGJ2. [ABSTRACT FROM AUTHOR]

Although there have been significant advances in the development of virtual-reality-based surgical simulations, there remain fundamental questions concerning the fidelity required for effective surgical training. A dual-station experimental platform was built for the purpose of investigating these fidelity requirements. Analogous laparoscopic surgical tasks were implemented on a virtual station and a real station, with the virtual station modeling the real environment with various degrees of fidelity. After measuring the subjects' initial performance on the real station, different groups of subjects were trained on the virtual station under a variety of conditions and finally tested on the real station. Experiments involved bimanual pushing and cutting tasks on a nonlinear elastic object. The results showed that force feedback results in significantly improved training transfer as compared to training without force feedback. The training effectiveness of a linear approximation model was approximately the same as that of a more accurate nonlinear model. [ABSTRACT FROM AUTHOR]