ECG measurement on a chair without conductive contact

For the purpose of long-term, everyday electrocardiogram (ECG) monitoring, we present a convenient method of ECG measurement without direct conductive contact with the skin while subjects sat on a chair wearing normal clothes. Measurements were made using electrodes attached to the back of a chair, high-input-impedance amplifiers mounted on the electrodes, and a large ground-plane placed on the chair seat. ECGs were obtained by the presented method for several types of clothing and compared to ECGs obtained from conventional measurement using Ag-AgCl electrodes. Motion artifacts caused by usual desk works were investigated. This study shows the feasibility of the method for long-term, convenient, everyday use

Biogenic CaCO3 and Opal Depositions and Their Latitudinal Comparison During the Past 600 ka in the Central Equatorial Pacific

The orbital-scale variations in biogenic CaCO3 and opal abundance in two piston cores collected in the central equatorial Pacific (core PC5101 from a southern site at _ and core PC5103 from a northern site at _ were compared to assess latitudinal differences. The correlation between the oxygen isotope stratigraphy of planktonic foraminifera (Globigerinoides sacculifer) of PC5103 with the LR04 stacks provides the age of PC5103 to be approximately 950 ka. The age of PC5103 was further refined by correlating the CaCO3 content with the well-dated core RC11-210. The age of PC5101 was also constrained by the same CaCO3 chronostratigraphic correlation with RC11-210, resulting in an age of approximately 650 ka. Distinct orbital-scale series of CaCO3 and opal variations appear to be parallel between the two cores during the past 600 ka, which are controlled mainly by eccentricity with an approximate periodicity of 100 ka. It is worth noting that the biogenic CaCO3 and opal deposition patterns in the two cores differ between interglacial and glacial periods. During interglacial periods the biogenic opal content is higher in the southern core than in the northern core, which corresponds with the present-day condition. In contrast the CaCO3 content is higher in the northern core, which is contradictory to the present-day northward decreasing CaCO3 deposition pattern from the Equator. The collection site of PC5101 is approximately 350 m deeper than that of PC5103, which significantly promotes CaCO3 dissolution and causes unexpectedly high CaCO3 content at the northern site in contrast to the biogenic opal content

Vagus Nerve Stimulation in Intractable Childhood Epilepsy: a Korean Multicenter Experience

We evaluated the long-term outcome of vagus nerve stimulation (VNS) in 28 children with refractory epilepsy. Of these 28 children, 15 (53.6%) showed a >50% reduction in seizure frequency and 9 (32.1%) had a >75% reduction. When we compared seizure reduction rates according to seizure types (generalized vs. partial) and etiologies (symptomatic vs. cryptogenic), we found no significant differences. In addition, there was no correlation between the length of the stimulation period and treatment effect. The seizure reduction rate, however, tended to be inversely related to the seizure duration before VNS implantation and age at the time of VNS therapy. VNS also improved quality of life in this group of patients, including improved memory in 9 (32.1%), improved mood in 12 (42.9%), improved behavior in 11 (39.3%), improved altertness in 12 (42.9%), improved achievement in 6 (21.4%), and improved verbal skills in 8 (28.6%). Adverse events included hoarseness in 7 patients, dyspnea at sleep in 2 patients, and wound infection in 1 patient, but all were transient and successfully managed by careful follow-up and adjustment of parameters. These results indicate that VNS is a safe and effective alternative therapy for pediatric refractory epilepsy, without significant adverse events

Photoplethysmogram measurement without direct skin-to-sensor contact using an adaptive light source intensity control

We developed a chair-attached, nonintrusive photoplethysmogram (PPG)measuring system for everyday life, unconstrained monitoring using nonskin-contacting sensor-amplifier circuits capable of emitting suitable light intensity adaptable to clothing characteristics. Comparison between proposed and conventional systems showed reasonable correlation and root-mean-squared error levels, indicating its feasibility for unconstrained PPG monitoring.This work was supported by a grant from the Advanced Biometric Research Center of the Korea Science and Engineering Foundation and the Strategic Technology Development Program funded by the Ministry of Knowledge Economy, Korea

The Safety and Efficiency of the Ultrasound-guided Large Needle Core Biopsy of Axilla Lymph Nodes

PURPOSE: To evaluate the safety and efficiency of the Ultrasound (US)-guided large needle core biopsy of axilla lymph nodes. MATERIALS AND METHODS: From March 2004 to September 2005, 31 patients underwent the US-guided core biopsy for axilla lymph nodes. Twenty five lesions out of 31 were detected during breast US, and 6 of 31 cases were palpable. Lymph nodes were classified based on their shape and cortical morphology. The core biopsy of axilla lymph nodes was performed on suspicious lymph nodes found during breast ultrasonography to find out whether the patients had a history of breast cancer or not. Among the 31 patients, 16 patients were associated with breast cancer. The lesion sizes varied from 0.6 cm to 3.3 cm (mean=1.59+/-0.76 cm). US-guided core biopsies were performed with 14 G needles with an automated biopsy gun. Total 3 or 5 specimens were obtained. RESULTS: Among the 31 cases of axilla lymph nodes core biopsies, 11 cases showed malignant pathology. Seven out of 11 cases were metastatic lymph nodes from breast cancer; 2 cases were from primary unknown and 2 cases from lymphomas. On the other hand, 20 histopathologic results of axilla lesions were benign: subacute necrotizing lymphadenitis (n=2), dermatopathic lymphadenitis (n=1), reactive hyperplasia (n=10) and free of carcinoma (n=7). CONCLUSION: The US-guided large needle core biopsy of axilla lesions is safe and effective for the pathological evaluation. The core biopsy is believed to be easy to perform if suspicious lymph nodes or mass lesions are found in the axillaope

The efficacy of memory load on speech-based detection of Alzheimer’s disease

IntroductionThe study aims to test whether an increase in memory load could improve the efficacy in detection of Alzheimer’s disease and prediction of the Mini-Mental State Examination (MMSE) score.MethodsSpeech from 45 mild-to-moderate Alzheimer’s disease patients and 44 healthy older adults were collected using three speech tasks with varying memory loads. We investigated and compared speech characteristics of Alzheimer’s disease across speech tasks to examine the effect of memory load on speech characteristics. Finally, we built Alzheimer’s disease classification models and MMSE prediction models to assess the diagnostic value of speech tasks.ResultsThe speech characteristics of Alzheimer’s disease in pitch, loudness, and speech rate were observed and the high-memory-load task intensified such characteristics. The high-memory-load task outperformed in AD classification with an accuracy of 81.4% and MMSE prediction with a mean absolute error of 4.62.DiscussionThe high-memory-load recall task is an effective method for speech-based Alzheimer’s disease detection

Comparisons of obesity assessments in over-weight elementary students using anthropometry, BIA, CT and DEXA

Obesity was characterized in Korean elementary students using different obesity assessment tests on 103 overweight elementary students from three schools of Jeonbuk Province. The body mass index (BMI) and obesity index (OI) were compared, and the data using DEXA and CT were compared with the data using BIA and a tape measure. The results of this study are as follows: first, 27 students who were classified as obese by OI were classified as overweight by BMI, and 3 students who were classified as standard weight by BMI were classified as overweight by OI. Secondly, by DEXA and BIA measurements, there was 1.51% difference in body fat percentage (boys 1.66%, girls 1.17%) and the difference in body fat mass between boys and girls was 0.77 kg (boys 0.85 kg, girls 0.59 kg), but those differences in body fat percentage and mass were not statistically significant. Thirdly, the average total abdominal fat (TAF) measured by CT scans of obese children was more significantly related with subcutaneous fat (r = 0.983, P < 0.01) than visceral fat (r = 0.640, P < 0.01). Also, TAF were highest significant with waist circumference by a tape measure (r = 0.744, P < 0.01). In summary, as there are some differences of assessment results between two obesity test methods (BMI, OI), we need more definite standards to determine the degree of obesity. The BIA seems to be the most simple and effective way to measure body fat mass, whereas waist/hip ratio (WHR) using a tape measurer is considered to be the most effective method for assessing abdominal fat in elementary students