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Our previous study showed that oyster hydrolysate (OH) protected against the liver damage caused by a single instance of ethanol (EtOH) binge drinking. Oyster broth concentrate (OBC) was discovered in the process of searching for a different substance derived from oysters (

We developed a low-vibrational-noise cooling configuration using continuous liquefaction of evaporated helium gas from a multi-channel SQUID gradiometer system for whole-head magnetoencephalography (MEG) measurements. The initial reduction of the vibration of the cryocooler was done by rigidly mounting the remote motor and cold head chamber on a concrete wall. This significantly reduces transmission of vibrations to the transfer tube, especially compared with mounting them on vertical aluminum frames. In addition, to reduce vibrations from a mechanical SQUID array insert, we completely eliminated it by mounting each SQUID gradiometer separately on the helmet surface within the vacuum space. Thus, vibrations from the boiling liquid helium and transmission from the transfer tube were both greatly reduced. Magnetic field noise of the 150-channel SQUID gradiometer system showed that the vibration-induced interference peaks are comparable in amplitude to those from a conventional MEG system without helium reliquefaction.

Background Although different body composition including fat adiposity has known to be associated with survival in patients with colorectal cancer (CRC), the clinical significance was inconsistent. We investigated prognostic impact of visceral and subcutaneous fat adiposity in patients with CRC after surgical resection. Material and methods This retrospective single center study included 987 stage I-III CRC patients (583 males, and 404 females) who underwent surgical resection between March 2005 and April 2014. Preoperative diagnostic computed tomography images were used to quantify visceral fat area (VFA) and subcutaneous fat area (SFA). The sex-specific optimal cut-off value for body fat composition was defined using the X-tile program. The Cox proportional hazards model was used to determine the correlation fat composition and disease-free survival (DFS). Harrell's concordance index (C-index) and integrated area under curve (iAUC) were used to evaluate the predictive ability of cut-derived stratification. Results In univariate analysis, high SFA (≥141.73 cm2 in males and ≥168.71 cm2 in females) and high VFA (≥174.38 cm2 in male and ≥83.65 cm2 in female) were identified as significant prognostic factors for better DFS (p = .001 and p = .003 respectively). However, multivariate analysis revealed that high SFA independently predicted longer DFS (HR 0.505; 95% CI 0.266-0.957; p = .036) whereas, high VFA did not (HR 0.656; 95% CI 0.402-1.071; p = .092). Combining stage and SFA-cutoff showed better discriminatory performance than the model using stage solitary with respect to C-index (0.667; 95% CI 0.623-6.711; p = .0098) and iAUC (0.601; 95% CI 0.556-0.620). Conclusion High SFA was correlated with better DFS in patients with CRC. Subcutaneous fat can have additive predictive capability when incorporated into clinical decision-making.

Accumulative alcohol hangovers cause liver damage through oxidative and inflammatory stress. Numerous antioxidant and anti-inflammatory reagents have been developed to reduce alcohol hangovers, but these reagents are still insignificant and have limitations in that they can cause liver toxicity. Oyster hydrolysate (OH), another reagent that has antioxidant and anti-inflammatory activity, is a product extracted through an enzymatic hydrolysis process from oysters (Crassostrea gigas), which can be easily eaten in meals. This study was aimed at determining the effects of OH on alcohol metabolism, using a single high dose of ethanol (EtOH) administered to rodents, by monitoring alcohol metabolic enzymes, oxidative stress signals, and inflammatory mediators. The effect of tyrosine-alanine (YA) peptide, a main component of OH, on EtOH metabolism was also identified. In vitro experiments showed that OH pretreatment inhibited EtOH-induced cell death, oxidative stress, and inflammation in liver cells and macrophages. In vivo experiments showed that OH and YA pre-administration increased alcohol dehydrogenase, aldehyde dehydrogenase, and catalase activity in EtOH binge treatment. In addition, OH pre-administration alleviated CYP2E1 activity, ROS production, apoptotic signals, and inflammatory mediators in liver tissues. These results showed that OH and YA enhanced EtOH metabolism and had a protective effect against acute alcohol liver damage. Our findings offer new insights into a single high dose of EtOH drinking and suggest that OH and YA could be used as potential marine functional foods to prevent acute alcohol-induced liver damage.

In this paper, we present OLED display technologies for large-size and premium TVs. Since high-quality TV needs total accuracy to reproduce input images, OLED panels must achieve stable luminance, uniformity at low luminance, and color uniformity. Using various OLED and TFT compensation technologies, we have successfully developed an OLED display with the “Real Black” image quality and high color uniformity. Additionally we have been developing OLED displays for broadcast monitors, which require much higher image quality than commercial TVs. We are now focusing on cost competitiveness of premium OLED displays.

Kernel rootkit is recognized as one of the most severe and widespread threats to corrupt the integrity of an operating system. Without an external monitor as a root of trust, it is not easy to detect kernel rootkits which can intercept and modify communications at the interfaces between operating system components. To provide such a monitor isolated from an operating system that can be compromised, most existing solutions are based on external hardware. Unlike those solutions, we develop a kernel introspection system based on the ARM TrustZone technology without incurring extra hardware cost, which can provide a secure memory space in isolation from the rest of the system. We particularly use a secure timer to implement an autonomous switch between secure and non-secure modes. To ensure integrity of reference, this system measured reference from vmlinux which is a kernel original image. In addition, the flexibility of monitoring block size can be configured for efficient kernel introspection system. The experimental results show that a secure kernel introspection system is provided without incurring any significant performance penalty (maximum 6% decrease in execution time compared with the normal operating system).

We have developed the world's first 65-inch UHD (also called 4K, 3840×2160) OLED TV with a coplanar-type IGZO(Indium Gallium Zinc Oxide) TFTs. In this paper, we discuss our excellent WRGB panel designs and circuits to achieve the high frame frequency and the product reliability.

The thin and slim design of 65-inch UHD OLED TV is reviewed in this paper. With its outstanding image qualities in UHD resolution is noteworthy the thin and slim curved screen. Reverse bonding technology enables the slim bezel design. A thin and curved back plate holds the module in shape and dissipates heat effectively. The source printed-circuit-boards are fixed directly to the backside of module to realize the ultra-thinedge design of the 65-inch OLED TV.

SUMMARY As sensitive magnetic sensors, magnetometers based on superconducting quantum interference devices can be used for the detection of weak magnetic fields. These signals can be generated by diverse origins, for example, brain electric activity, myocardium electric activity, and nuclear precession of hydrogen protons. In addition, weak current induced in the low-temperature detectors, for example, transition-edge sensors can be detected using SQUIDs. And, change of magnetic flux quantum generated in a superconducting ring can be detected by SQUID, which can be used for realization of mechanical force. Thus, SQUIDs are key elements in precision metrology. In Korea, development of low-temperature SQUIDs based on Nb-Josephson junctions was started in late 1980s, and Nb-based SQUIDs have been used mainly for biomagnetic measurements; magnetocardiography and magnetoencephalography. High-Tc SQUIDs, being developed in mid 1990s, were used for magnetocardiography and nondestructive evaluation. Recently, SQUID-based low-field nuclear magnetic resonance technology is under development. In this paper, we review the past progress and recent activity of SQUID applications in Korea, with focus on biomagnetic measurements.

Background: Accurate identification of patients with acute coronary syndrome (ACS) is often difficult especially when an electrocardiogram (ECG) does not show typical elevation of ST segment. The aim of the present study was therefore to evaluate the efficacy of magnetocardiography (MCG) for diagnosis of ACS in patients with acute chest pain presenting without ST segment elevation. Methods and Results: In the present retrospective study 364 patients with the suspected ACS without ST segment elevation were selected. Significant coronary artery disease (CAD) was defined as a stenosis ≥50% in at least one of 16 segments of the 3 major coronary arteries and their branches. The MCG recordings were obtained at resting state using a 64-channel MCG system in a magnetically shielded room. The patients were classified on the basis of the probability distribution. The presence of significant CAD was identified with a sensitivity of 84.0% and a specificity of 85.0%, compared to 44.7% and 89.8% on ECG. In the subgroup of patients without specific findings on ECG or biomarker test, MCG had a sensitivity of 73.5% and a specificity of 82.3%. Conclusions: MCG was acceptably sensitive and specific in identifying patients with ACS even in the absence of specific findings on ECG and positive biomarker tests. Thus, MCG seems beneficial for the early triage of patients with acute chest pain. (Circ J 2010; 74: 1424 - 1430)

Electrophysiologic information as well as anatomic information to detect coronary artery disease is important for accurate diagnosis. A diagnostic tool that can detect patients with unstable angina pectoris (UAP) or non-ST elevation myocardial infarction (NSTEMI) with severe stenosis would be beneficial for patients and clinicians. Magnetocardiography has been recognized as a noncontact, noninvasive, fast tool to detect ischemic coronary artery disease and provide direct electrophysiologic information from the heart. In this study, 10 magnetocardiographic (MCG) parameters from 4 groups, including 185 young controls, 19 age-matched controls (AMCs), 110 patients with UAP, and 83 patients with NSTEMIs, were analyzed. A 64-channel MCG system in a magnetically shielded room was used. All 10 parameters showed significant differences (p

In this paper, the effects of electromagnetic fields from the frequency band of digital wireless telephones on a superconducting quantum interference device (SQUID) were experimentally investigated. A first-order planar gradiometer based on the double relaxation oscillation SQUID (DROS) was operated without low-frequency magnetic shielding, and was exposed to radiated electromagnetic fields in the frequency range of 300 MHz-2 GHz. The experiments have been performed in a fully anechoic chamber to minimize reflected waves in the chamber. The flux-to-voltage transfer and the field sensitivity of the gradiometer have been observed under the irradiation of fields. Results show that the performance of the gradiometer was significantly affected at a typical power level of the digital wireless telephones for both horizontally and vertically polarized electromagnetic waves. The noise level of the DROS output voltage also increases as the strength of the external fields becomes higher.

Magnetocardiograms (MCG) measured using multichannel SQUID sensors of different pickup coil configuration have different magnetic signal waveforms and field distributions. In order to compare MCG data measured using different multichannel systems and to make standard format of data, we fabricated and characterized three different MCG systems each having different structure of pickup coils. Pickup coils are integrated magnetometer, planar first-order gradiometer with baseline 4 cm, planar second-order gradiometer with baseline 5 cm. The magnetometer system measures normal component of MCG fields with 61 channels, and the two planar gradiometer systems measure tangential components of MCG fields each with 64 channels. The SQUIDs are double relaxation oscillation SQUID type fabricated using Nb/Al-oxide/Nb thin film process on Si wafers. From the measured tangential field maps, normal component waveforms and field maps were reconstructed using minimum norm estimation method. The average correlation values over one cardiac cycle between the measured B z waveforms and reconstructed B z waveforms were higher than 90% both for the first-order and second-order gradiometers, meaning that we can transform reliably the tangential measurement results to the conventional normal measurement scheme.

A double relaxation oscillation SQUID with a reference junction (RJ-DROS) already has a fixed reference current, so that it holds a fixed flux-to-voltage characteristics when fabricated. When an additional current flows through the reference junction but not through the signal junction in the RJ-DROS, we have obtained the variation of its characteristics. The additional reference current has an effect on reducing the fixed reference current, which results in changing averaged relaxation voltage and transfer coefficient. In particular, while the critical current of the signal SQUID exceeds the reference current, the averaged relaxation voltage at the reference junction is enlarged by the added bias current combined with an additional current and an initial bias current. Therefore the additional reference current can provide the RJ-DROS with variable modulation depth and width within the operating range. Although the characteristics of RJ-DROSs are fixed differently each to each when they are fabricated, the additional current can adjust their characteristics to the same one, which is useful for controlling DROSs in a multichannel DROS system. However, an input-bias current in the preamplifier detecting the outputs at the reference junction, acts as an additional current, and then makes the reference current shift from the optimum current or deviate from the operating range, the input-bias current needs to be regulated within the operating range

We developed a magnetocardiogram (MCG) system measuring tangential field components using planar gradiometers. The SQUID insert has 64 planar gradiometers, of which 32 measure the x-component and the other 32 measure the y-component, where the chest surface is in the x and y plane. The SQUID sensor is a double relaxation oscillation SQUID type with high flux-to-voltage transfers. Thus, a room-temperature dc preamplifier with a modest input voltage noise could be used to detect the SQUID output voltage directly. The pickup coils are first-order planar gradiometers with a baseline of 4 cm, and they were connected to the input coils using a superconductive bonding of Nb wires. The sensor coverage area of the 64 channels is 190 mm in diameter, and the average boil-off rate of liquid He is 3.6 L/d in everyday operation of the SQUID system. The SQUID operation of the 64 channels was done by digital controls and the average noise of the MCG system was 4.6 fT Hz−1/2 at 100 Hz, inside a magnetically shielded room.

We propose independent component analysis (ICA) as a pre-process for synthetic aperture magnetometry (SAM) in magnetocardiogram. SAM is a very useful method for source current imaging. However, SAM cannot separate one source from the others when there are time-correlated multi-sources, especially for successively active sources. The proposed method compensates the intrinsic drawback of SAM with ICA, which is feasible for 3-D imaging of the myocardial current distribution of specific temporal features. By using our method, we successfully localized an accessory pathway of a patient suffering from the WPW syndrome.

We present a 62-channel double relaxation oscillation SQUID (DROS) planar gradiometer system to measure magnetocardiogram (MCG) signals tangential to the chest surface. The DROSs were fabricated using Nb/Al-oxide/Nb junctions, and provided flux-to-voltage transfers of larger than 1 mV//spl Phi//sub 0/ typically, which is large enough for direct readout by room-temperature flux-locked loop (FLL) circuits. The analog FLL circuits and digital control circuits are made in a single printed circuit board. The planar gradiometers are integrated, series-connected first-order pickup coils with a baseline of 4 cm. White noise level of the planar gradiometer is about 1.5 (fT/cm)//spl radic/Hz or 6 fT//spl radic/Hz, operated inside a magnetically shielded room. The planar gradiometers were arranged to measure dB/sub x//dz and dB/sub y//dz simultaneously. The covering area of the 62 channel system is 162 mm /spl times/ 162 mm, which is smaller than the sensor coverage area of vertical measurement systems, but large enough to measure the essential MCG field distribution in a single position measurement.

Compact and low-cost SQUID electronics to operate double relaxation oscillation SQUIDs (DROSs) has been constructed for detecting magnetocardiogram (MCG) fields. SQUID electronics consists of low-noise preamplifier with a white noise of 0.6 nV//spl radic/Hz, flux-locked loop (FLL) circuit with auto-reset, and interface circuit to control FLL using 3 digital lines from a computer. The automatic control software adjusts SQUID parameters to the optimum operating condition within 15 seconds for 62 channels. Outputs of FLL circuits are passed through the hardware filter box to the 64-channel data acquisition board. Each SQUID electronics for FLL and digital control is built together on a printed circuit board of 45 mm /spl times/ 95 mm. When SQUID electronics is connected to DROS gradiometer with typical flux-to-voltage transfers of 1 mV//spl Phi//sub o/, the noise contribution of FLL circuit is about 0.6 /spl mu//spl Phi//sub o///spl radic/Hz or 0.6 fT//spl radic/Hz at 100 Hz, low enough to measure MCG fields.

Multichannel superconducting quantum interference device (SQUID) systems based on double relaxation oscillation SQUIDs (DROS) were developed for measuring magnetocardiography (MCG) and magnetoencephalography (MEG) signals. Since DROS provides large flux-to-voltage transfer coefficients, about 10 times larger than the DC SQUIDs, direct readout of the SQUID output was possible using compact roomtemperature electronics. Using DROSs, we fabricated two types of multichannel systems; a 37-channel magnetometer system with circular sensor distribution for measuring radial components of MEG signals, and two planar gradiometer systems of 40-channel and 62-channel measuring tangential components of MCG or MEG signals. The magnetometer system has external feedback to eliminate magnetic coupling with adjacent channels, and reference vector magnetometers were installed to form software gradiometers. The field noise of the magnetometers is around 3 fT/ Hz at 100 Hz inside a magnetically shielded room. The planar gradiometer systems have integrated first-order gradiometer in thin-film form with a baseline of 40 mm. The magnetic field gradient noise of the planar gradiometers is about 1 fT/cm/Hz at 100 Hz. The planar gradiometers were arranged to measure field components tangential to the body surface, providing efficient measurement of especially MCG signals with smaller sensor coverage than the conventional normal component measurements.

We developed multichannel SQUID magnetometer and gradiometer systems based on double relaxation oscillation SQUIDs (DROS) for use in biomagnetic studies, such as magnetoencephalogram (MEG). DROS consists of two SQUIDs (signal SQUID and reference SQUID) in series, and a relaxation circuit of an inductor and a resistor. Specially, we used single reference junction instead of the reference SQUID. Since DROS magnetometer has about 10 times lager flux-to-voltage transfer coefficient than dc SQUID, we can use simple flux-locked loop electronics for SQUID operation. The measured noise at 100 Hz was 3 fT/ √Hz for the magnetometer and 4 fT/ √Hz for the planar gradiometer, which are low enough for neuromagnetic measurements. We also constructed two kinds of multichannel SQUID systems, 40-channel and 37-channel system. Using this system, we measured several MEG signals.

We constructed a multichannel superconducting quantum interference device (SQUID) magnetometer system for magnetoencephalogram measurements. The SQUID is based on the double relaxation oscillation SQUID (DROS), which consists of a hysteretic signal SQUID and a reference junction, and shunted by a relaxation circuit of a resistor and an inductor. With the high flux-to-voltage transfers, usually larger than 1 mV//spl Phi//sub 0/, simple flux-locked loop circuits could be used for SQUID operation. The SQUID system consists of 37 integrated magnetometers, distributed on a hemispherical surface, and external feedback scheme was used to eliminate magnetic coupling with the adjacent channels. In addition to the 37 signal channels, 8 reference channels were installed to pickup background noise and to apply software gradiometer. The average noise level of the magnetometers is about 3 fT//spl radic/Hz at 100 Hz, operated inside a magnetically shielded room. The magnetometer system was applied to measure auditory-evoked fields.

We have fabricated a single-stage superconducting quantum interference device (SQUID) current amplifier for detecting pulse outputs of a superconducting microcalorimeter. The current amplifier is made of a double relaxation oscillation SQUID (DROS) that provides a high flux-to-voltage transfer of about 1mV//spl Phi//sub 0/ and a large modulation depth of 80 /spl mu/V. Due to the high flux-to-voltage transfer, the voltage output of the DROS is measured directly with a room-temperature dc preamplifier. The bandwidth of the current amplifier is measured to be 1.2 MHz. Typical noise of the DROS current amplifier is about 6 pA//spl radic/Hz.

An optical receiver system composing 13 serial data restore/synchronizer modules and a single module combiner converted optical 32-bit serial data into 32-bit synchronous parallel data for a computer to acquire 152-channel magnetoencephalography (MEG) signals. A serial data restore/synchronizer module identified 32-bit channel-voltage bits from 48-bit streaming serial data, and then consecutively reproduced 13 times of 32-bit serial data, acting in a synchronous clock. After selecting a single among 13 reproduced data in each module, a module combiner converted it into 32-bit parallel data, which were carried to 32-port digital input board in a computer. When the receiver system together with optical transmitters were applied to 152-channel superconducting quantum interference device sensors, this MEG system maintained a field noise level of 3 fT/√Hz @ 100 Hz at a sample rate of 1 kSample/s per channel.

Double relaxation oscillation SQUIDs (DROSs) provided high flux-to-voltage transfers of larger than 1 mV Φ0−1 and simple flux-locked loop circuits were used for SQUID operation. We constructed two multichannel systems based on DROSs. The first system is a 40-channel planar gradiometer system consisting of integrated first-order pickup coils. average noise level of the 40 channels is 1 fT cm−1 Hz−1/2 at 100 Hz, corresponding to a field noise of 4 fT Hz−1/2, operating inside a magnetically shielded room. The second one is a 37-channel magnetometer system with 37 integrated magnetometers distributed on a spherical surface and measures field component normal to the head surface. The average noise of the magnetometers is 3 fT Hz−1/2 at 100 Hz. The two systems were applied to measure neuromagnetic fields.

The high-T/sub c/ superconducting quantum interference device (SQUID) gradiometer system was developed for operation in unshielded environment. The system consists of the first-order gradiometer and the flux-locked loop electronics. YBa/sub 2/Cu/sub 3/O/sub 7/ single-layer first-order SQUID gradiometers were fabricated on 15 mm/spl times/7.5 mm SrTiO/sub 3/ bicrystal substrates with a baseline of 7 mm. The gradient sensitivities at 77 K and 100 Hz were 0.1 pT/(cm/spl radic/Hz) in magnetic shielding and 1.4 pT/(cm/spl radic/Hz) when operated unshielded in our laboratory. The high-T/sub c/ SQUID gradiometer system demonstrated successful measurement of small magnetic fields in a laboratory environment without any shields.

We have fabricated a four-channel SQUID gradiometer system based on double relaxation oscillation SQUIDs (DROSs) with a reference junction. For a biomagnetic multichannel system, we simplified the DROS design by using a single reference junction instead of the reference SQUID. The SQUIDs were fabricated from hysteretic Nb/AlOx/Nb junctions using a simple four-level process. The DROSs provided very large flux-to-voltage transfers of typically 3 mV/Φ0, enabling direct readout by a room-temperature dc preamplifier, and consequently simple flux-locked loop electronics were used. To realize a compact and reliable gradiometer, a first-order planar pickup coil was integrated on the same wafer with the SQUID. The flux noise of the gradiometer is about 5 μΦ0/√Hz at 100 Hz, corresponding to a field noise of 8 fT/√Hz, measured inside a magnetically shielded room. A compact four-channel planar gradiometer system was implemented and operated to measure auditory evoked fields.

Magnetocardiography (MCG) has been proposed as a noninvasive diagnostic tool to risk-stratify patients with myocardial infarction (MI) and ischemia. The purpose of this study is to find the MCG parameters that are sensitive enough to detect the non-ST-segment elevation myocardial infarction (NSTEMI) patients.MCG data were recorded and analyzed from 165 young controls (mean age = 27.2 +/- 9.0 years), 57 age-matched controls (mean age = 55.9 +/- 10.5 years) and 83 NSTEMI patients (mean age = 59.7 +/- 11.1 years). The MCG recordings were obtained using a 64-channel MCG system in a magnetically shielded room. Statistical analyses were performed for 24 parameters derived from QRS-, R-, T-wave, and ST-T period. Binary boundaries to detect NSTEMI patients out of control subjects were found using the receiver operating characteristic (ROC) curve for each parameter.Fifteen parameters showed a significant difference (P0.05 and P0.01) between NSTEMI and both of the control groups. For detection of NSTEMI, the angle of the maximum current and the filed map angle on T-wave peak showed the highest diagnostic performance from 75% to 92% including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value (area under ROC curve = 0.87 approximately 0.93).Our study showed that MCG has potential clinical application for detection of NSTEMI and should be further investigated.

Magnetocardiography (MCG) has been introduced as an innovative non-invasive diagnostic tool to identify various heart diseases. However, there have been little data on the reliability of MCG parameters. The purpose of this study is to examine the test-retest reliability of different diagnostic parameters derived from MCG. We investigated short-, intermediate-, and long-term reliability of nine parameters from T (max/3)-T (max) interval, and five parameters from each time point such as QRS-wave, the peak of R-, and T-wave were evaluated. Short-term reliability was tested in the youngest 20 subjects (mean age = 26.3 +/- 4.9 years) in three sessions separated by 5 min. Intermediate-term reliability was tested in the 35 subjects with coronary artery disease (CAD) (65.1 +/- 7.1 years) with two recording sessions each in the morning and afternoon, separated by more than four hours. Long-term reliability was tested in seven subjects (37.1 +/- 8.8 years) using seven daily sessions. Interclass correlation coefficients (ICC) showed that test-retest reliability was good to excellent (0.99 > or = ICC > or = 0.80) for six out of nine parameters within T (max/3)-T (max). In addition, all parameters on the peak of R-wave, T-wave, and QRS-wave integrated were good to excellent (0.99 > or = ICC > or = 0.80) except for one parameter of CAD patients showing lower ICC values under 0.7. In conclusion, our study showed that the test-retest characteristics of the studied MCG parameters are generally stable and reliable over periods of minutes to days in subjects with different age spectrums.

We carried out an magnetoencephalography (MEG) study to record cortical responses elicited in the left hemisphere by ending verb phrases, which had syntactic or semantic anomalies, in Korean sentences of subject-object-verb order. Using the high temporal and spatial resolution of MEG, the study was aimed at identifying neural activities that occur during a latency course associated with the syntactic or semantic process in the spoken sentence. Major responses, distinct from the responses to normal sentences, were observed in two latency periods of about 400 and 600 ms following the onset of the verb phrase. Source localization of the grand average fields indicated separate activities in the inferior frontal region and the vicinity of the auditory cortex for the first 400-ms response to the syntactic anomaly. The region around the auditory cortex was indicated for the response to the semantic anomaly in a similar latency. The second 600-ms response indicated activity around the middle temporal gyrus inferior to the auditory cortex for both syntactic and semantic anomalies. The results are discussed with reference to the ERP components established for Indo-European languages, and the possibility of concurrent processing of syntactic and semantic aspects is suggested.

We developed a cryocooled SQUID system with which human magnetocardiogram (MCG) and possibly magnetoenceparogram (MEG) can be measured. To reduce cyclic magnetic noises originating from the regenerator of the cold heads of the cryocooler, a superconductive shield (99.5% Pb) was used to protect the SQUID sensors, and a ferromagnetic shield (78% Ni alloy) was used to screen the cold head. In addition, the SQUID sensors' chamber was placed at a distance of 1.8 m from the cold head chamber to install the cold-head chamber outside the magnetically shielded room (MSR) for future development. The loss in cooling power due to the increased distance was compensated by increasing the number of thermal rods, and thus the SQUID sensor and superconductive shield could be refrigerated to 4.8 K and 5 K, respectively. The superconductive shield successfully rejected thermal noise emitted from metallic blocks used to improve thermal conduction. The noise of the SQUID system was 3 fT/Hz1/2, and the cyclic magnetic noise could be reduced to 1.7 pT. We could obtain a clear MCG signal while the entire cryogenics was in operation without any special digital processing.

We developed an optical transmission module consisting of 16-channel analog-to-digital converter (ADC), digital-noise filter, and one-line serial transmitter, which transferred Superconducting Quantum Interference Device (SQUID) readout data to a computer by a single optical cable. A 16-channel ADC sent out SQUID readouts data with 32-bit serial data of 8-bit channel and 24-bit voltage data at a sample rate of 1.5 kSample/s. A digital-noise filter suppressed digital noises generated by digital clocks to obtain SQUID modulation as large as possible. One-line serial transmitter reformed 32-bit serial data to the modulated data that contained data and clock, and sent them through a single optical cable. When the optical transmission modules were applied to 152-channel SQUID magnetoencephalography system, this system maintained a field noise level of 3 fT/√Hz @ 100 Hz.

Background Obesity is a complex problem that is now considered a chronic metabolic disease. In Korea, phentermine has been widely used for the treatment of obesity in the primary care setting since 2004. However, there have been very few studies on the safety and efficacy of phentermine. To investigate the safety and efficacy of this drug, a postmarketing surveillance study was performed. Methods A total of 795 patients with obesity (body mass index ≥ 25 kg/m(2)) were enrolled from 30 primary care centers in Korea from September 2006 to November 2007. Patients were examined to ascertain safety and efficacy at 4-, 8-, and 12-week intervals. The criterion for efficacy was defined as a weight loss ≥ 5% of body weight. Results Of the 795 enrolled patients, 735 (92.5%) were evaluated in safety assessments and 711 (89.4%) was included in efficacy assessments. A total of 266 adverse events (AEs) were reported by 218 patients (30.6%), and no serious AEs were reported. Among 711 patients, 324 patients (45.6%) lost ≥ 5% of their body weight. The mean weight loss was 3.8 ± 4.0 kg. Conclusion AEs are commonly associated with phentermine, even though phentermine is effective for weight loss and relatively well-tolerated.

We developed an ultra-low field (ULF)-nuclear magnetic resonance (NMR) measurement system capable of working with a measurement field (Bm) of several micro-tesla and performed basic NMR studies with a double relaxation oscillation superconducting quantum interference device (DROS) instead of conventional dc-SQUIDs. DROS is a SQUID sensor utilizing a relaxation oscillation between a dc-SQUID and a relaxation circuit; the new unit consists of an inductor and a resistor, and is connected in parallel with the SQUID. DROS has a 10 times larger flux-to-voltage transfer coefficient (∼mV/ϕ0) than that of the dc-SQUID, and this large transfer coefficient enables the acquisition of the SQUID signal with a simple flux-locked-loop (FLL) circuit using room temperature pre-amplifiers. The DROS second-order gradiometer showed average field noise of 9.2 μϕ0/√Hz in a magnetically shielded room (MSR). In addition, a current limiter formed of a Josephson junction array was put in a flux-transformer of DROS to prevent excess...

Directly-coupled dc superconducting quantum interference device (SQUID) magnetometers have been fabricated on SrTiO3 bicrystal substrates with 30° misorientation angle. YBa2Cu3O7-δ single layers were deposited by laser ablation and patterned by standard photolithography and Ar ion milling. The magnetometer consists of a 9 mm×9 mm pickup loop coupled to a long slit. The magnetometers have been characterized at 77 K using conventional flux-locked loop electronics with a bias current reversal. The magnetometers exhibited high junction resistance of up to 10 Ω and large voltage modulation depth as high as 65 µV with a flux-to-voltage transfer function of 253 µV/Φo at the working point. A magnetic field noise level of 74f T/√ Hz at 1 kHz and below 100f T/√ Hz down to 4 Hz, including electronics noise, was achieved inside a magnetically shielded room. The performance of the magnetometer was demonstrated by magnetocardiograms with high quality.

We have characterized directly-coupled dc superconducting quantum interference device (SQUID) magnetometers for multichannel applications. YBa2Cu3O7-δ single layers were deposited on 1 cm×1 cm SrTiO3 bicrystal substrates by laser ablation and patterned by Ar ion milling. From the comparison of the experimental data with the theoretical predictions, we have shown that the degradation of the modulation voltage is caused by the thermal noise flux and thermal noise rounding in the I–V curve. In addition, the SQUID noise at low frequencies could be explained well by critical current fluctuations of the Josephson junctions with a value of S I 0 /I 0 2≈(1–4)×10-8/Hz. We have achieved a magnetic field noise of 170 fT/√ Hz at 1 Hz. We demonstrated the use of our magnetometers to obtain realtime traces of a magnetocardiogram inside a magnetically shielded room.