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Very high frequency (VHF)-line impedance stabilization network (VHF-LISN), which is defined as the termination device for mains cable of equipment under test to specify the input impedance of each line at the mains power supply outlet, can improve correlation between test sites that perform radiated emission measurement. Balanced and unbalanced types of VHF-LISN are currently under proposal with International Special Committee on Radio Interference (CISPR) as a device for prescribing the terminating condition of the power supply cable. Simulation analysis with common mode (CM)/differential mode (DM) signal sources was performed to investigate the emission characteristics with the two types of termination devices under several measurement arrangements that used two-wire and three-wire mains cables. Furthermore, to confirm the validity of the simulation analysis, measurement of a versatile comb-generator-operated by ac mains was performed under the same test arrangement and two types of termination devices. Quasi CM/DM signal from an ac-operated comb generator was injected back into the mains cable of the same comb generator. This article explains how we ascertained the radiated emission characteristics with each termination device, and provides guidance for their appropriate usage.

A mode division multiplex transmission system that assigns signals to the eigenmodes of a transmission line was proposed for a cable that is uniform in the longitudinal direction. The transmission characteristics when the proposed method is used in a 1m long shielded untwisted 4-wire cable were verified by circuit simulation. It is shown that the proposed method enables four-channel simultaneous transmission. In addition, the proposed method significantly improves the crosstalk compared to the differential and single-ended transmission methods.

Radiated emission from shielded twisted pair (STP) cable was calculated using a chain-parameter-matrix. The series connection of the matrix represented the transmission line inside the shield, and the common-mode (CM) current was obtained by solving the matrix equation. The induction voltage on the outside of the shield was determined from the CM current using the shield’s transfer impedance. The current on the outside of the shield was calculated from this induction voltage. And then, the radiated electric field was calculated from this current. The matrix elements representing the transmission line between conductors and shield were determined from the measurement, and the transfer impedance was also determined from the measurement. The line constants between shield and ground were determined from the theory by assuming the shield as a copper rod. The maximum current on the outside of the shield and the maximum radiated electric field were measured in the frequency range from 30 MHz to 300 MHz, and these were compared to the calculated value. The calculation results of the maximum current intensity were well agreed with the measured value, and the calculation results of the maximum radiated electric-field strength were almost agreed with the measured value.

In this article, we introduce an alternative terminating condition for the AC mains cable of Equipment Under Test (EUT) with appropriate common mode impedance by VHF-LISN in radiated emission measurements at test sites. In Round Robin Testing (RRT) conducted by CISPR SC-A/I joint ad hoc group 6 (JAHG6), inter-laboratory reproducibility was significantly improved by setting terminating conditions for the AC mains cable of EUT, thus, reflecting the same results as those of previous RRT conducted by CISPR/SC-I. However, since only a conventional comb generator was employed, differences in radiated emission of EUT with and without AC mains cable termination by VHF-LISN were not clear. In this RRT, we performed actual product measurement (prepared by ten participating laboratories) and compared the accumulative probability distributions of radiated emissions by using two types of VHF-LISN of different termination impedances and without a termination device (deemed as the actual operating condition). From the investigation results, mains cable termination with VHF-LISN of a specific common mode impedance was deemed to be valid for radiated emission measurement.

Herein, the anesthetization of Bombyx mori silkworms via the water narcosis treatment by soaking in room-temperature water for 1 h was found effective in keeping the tensile strength of its forcibl...

Silk fibroin (SF) from Bombyx mori has superior properties as both a textile and a biomaterial, and has been used to functionalize the surfaces of various medical inorganic materials including titanium (Ti). In this paper, we endowed SF with reversible binding ability to Ti by embedding a titanium binding motif (minTBP-1, RKLPDA). Artificial SF proteins were first created by conjugating gene cassettes for SF motif (AGSGAG) and minTBP-1 motif with different ratios, which have been shown to bind reversibly to Ti surfaces in quartz crystal microbalance analyses. Based on these results, the functionalized SF (TiBP-SF) containing the designed peptide [TS[(AGSGAG)3 AS]2 RKLPDAS]8 was prepared from the cocoon of transgenic B. mori, which accelerates the ossific differentiation of MC3T3-E1 cells when coated on titanium substrates. Thus, TiBP-SF presents an alternative for endowing the surfaces of titanium materials with osseointegration functionality, which would allow the exploration of potential applications in the medical field. This article is protected by copyright. All rights reserved.

Electromagnetic fields unintentionally radiated from power-line communications used in factories interfere with wireless communications. It is important to distinguish the mechanism of this undesired and unintentional radiation from that of wired communication as it affects wireless communications. In particular, unintentional radiated emissions should be reduced in order to construct a stable wired/wireless communication network. This paper focuses on power-line communication as it is used in a factory. The power distribution network in the factory consists of multiple cables bundled together. The effects of cables other than the power cable that applies the communication signal to the radiated electromagnetic field are investigated. Some of the signal power reaching the reciever is converted into common-mode current by an imbalance mismatch. The common-mode current is one of the main causes of unwanted electromagnetic radiation. To predict this conversion, an imbalance difference model is created to account for multi-conductor transmission lines such as those in the power distribution network of the factory. The proposed model can calculate the amount of common-mode excitation associated with changes in the load condition of the power lines. To verify the proposed method, the authors measured the change in common-mode current due to the difference in pairs of power lines to which the signal is applied. The calculation using the proposed model could estimate the amount of reduction in common-mode current to within an error of 1 dB.

The radiated emission of the power line communication (PLC) system should be investigated to maintain electromagnetic compatibility. Recently, the development of applying the PLC system to factories and offices was started. In these environments, many cables are arranged in the cable tray. Therefore, the multi-cable effect should be investigated. In this paper, the multi-cable effect was examined by using the scale model. The 0.5 times scale model was constructed in the semi-anechoic chamber, and the maximum common-mode (CM) current was measured by changing position along with the cable. The measured result was agreed with the result using the full-size original model. The experiment by using five cables suggested that the influence by the conductive loss and the dielectric loss of cable was not large for the maximum CM current, and the CM current was dominated by the cancellation effect of the in-phase currents flowing on the cables. The investigation for dependency of the position of the signal apply was indicated that the effect can be roughly estimated from the current division factor.

Reproducibility of radiated disturbance measurements is influenced by the line impedance of the power source used for EUT. A VHF-LISN was proposed to solve this issue. A VHF-LISN can define line impedance so as to avoid such influences caused by different line impedances for connection points at different test sites. At present, two proposed types of VHF-LISN - balanced termination and unbalanced termination - are being considered for implementation in CISPR 16 basic measurement standards. Round robin testing was conducted to investigate the effectiveness of improving reproducibility of radiated emission measurement with two types of VHF-LISN, using a versatile comb generator having two signal source modes, common mode (CM) and differential mode (DM), and by using both 2-wire and 3-wire AC mains cable respectively. CMAD termination was provided as an option. The testing concluded that reproducibility between test sites was improved by VHF-LISN termination for both CM and DM emission sources with CMAD termination effectiveness proving to be limited in the case of 2-wire mains cable being used in CM signal source measurements.

In this paper, reduction effect of a common-mode filter is discussed. When the performance of a common-mode filter is evaluated, it is necessary to consider not only S CC21 but also S CD21 . Using these two parameters, the common-mode current flowing on the secondary side of the common-mode filter was formulated. Common-mode current is a summation of two causes: common-mode transmission and differential mode conversion from a signal source. The common-mode current depends on not only the phase relationship between S CC21 and S CD21 of the common-mode filter but also the phase relationship between the differential mode and the common mode of the signal source. Even if the same common-mode filter is used on a differential signaling system, the common-mode current increases or decreases depending on the phase of the differential mode voltage and the common-mode voltage at the signal source.

Power line communication (PLC) is the technology that uses a power line as a signal line. Because an imbalance of the power line is generally larger than that of the communication line, we should take care of radiated emission from the PLC cable. A small-scale model can be applied to evaluate easily the radiated emission from PLC cables for large structures. In a scale model, all structures in the PLC system need to be manufactured as 1/n size to satisfy complete equivalence between the reference model and its scale model, though it is difficult to fabricate the fine structure such as conductors in a cable smaller. Therefore we investigated the effect on common-mode current when some parameters of the scale model were not scaled down perfectly. As a result, a reliable scale model was obtained to evaluate peak common-mode currents in resonant frequency even if some parameters of the structure were incompletely scaled. Furthermore, the cable length dependency of common-mode current was evaluated experimentally by using the scale model.

The common-mode filter (CMF) is a key device for suppressing emissions radiated from telecommunication cables. Recent serial interfaces deliver the necessity of considering that common-mode (CM) disturbances are converted from the differential mode (DM) telecommunication signals by a CMF. To examine this phenomenon, this study investigated the $S_{\text{cd}21}$ characteristic, which is one of the mixed-mode S-parameters. Two types of CMFs whose $S_{\text{cd}21}$ were different were examined. A signal was supplied to an unshielded twisted pair (UTP) cable through the CMF. The emission from the cable was measured using a setup complying with CISPR 25. Then, the relationship between the ratio of CM to DM signals and the emission level was investigated. The results showed that the emission level decreased as a result of employing the lower $S_{\text{cd}21}$ CMF and that the emission level was linearly proportional to the ratio of the CM to DM signals. The results indicate that ${S}_{\text{cd}21}$ is an essential parameter with which to evaluate CMFs used in telecommunication ports of serial interfaces.

In this article, we investigated the influence on radiated emission characteristics in the condition that an mains cable of equipment under test (EUT) leaving from test area was terminated by balanced and unbalanced type common mode impedance stabilization devices. To investigate the influence by the same termination condition of mains cable, we performed the simulation analysis on radiated emission characteristics of the product with 3 wires (3W) mains cable which has a protective earth (PE) line and a product with 2 wires (2W) mains cable which has no PE line. With regard to this analysis, we conducted also the actual measurements with two types of mains cable by using a comb generator. From these results, we were able to estimate that the radiated emission from the products having 3W mains cable were became from 3 to 5 dB lower at a VHF band than the product having 2W mains cable. Furthermore, we investigated the influence on radiated emission characteristics by two terminating conditions when EUT setups including cable arrangement were changed. As a result, there was no difference compared with the maximum standard deviation of without device. This means it is insufficient only by establishing the termination condition of mains cable.

Silkworms are economically important insects that have the ability to produce large amounts of silk. They have mass breeding methods and silk glands, which are specialized tissues that secrete silk fibroin and sericin. Thus, the production of recombinant proteins in a transgenic silkworm system is a promising approach. We developed a silkworm, Bombyx mori, as a host expression insect for recombinant proteins and successfully produced different proteins including antibodies, glycoproteins, and membrane receptors. The thyroid hormone receptor (TR) is a regulatory factor for many physiological phenomena. It is a lipophilic protein that has DNA-binding and ligand-binding domains. Based on our previous experiences, it was inferred that the recombinant TR easily formed aggregates and precipitates which is potentially due to an unstructured hinge domain. We applied the silkworm expression system to produce mice TRβ1 that was fused with glutathione S-transferase. Using 160 larvae, the yield of the recombinant GST-TRβ was approximately 4 mg, and the purified GST-TRβ completely retained its physiological activity. Our results indicated that the recombinant TRβ was secreted extracellularly using the silk fibroin signal peptide sequence. Moreover, we found that the expression system of silkworms was applicable to nuclear proteins.

The differential mode impedance (DMZ) and the longitudinal conversion loss (LCL) are important parameters to introduce high-speed power line communication (PLC) systems. Therefore, we should evaluate the DMZ and LCL in a factory environment because the three-phase power distribution system has been employed in factories. The admittance matrix elements at the power distribution board were determined from S-parameter measured with a vector network analyzer. An isolation probe was developed to measure S-parameters under high voltage applying conditions. Measurements were carried out at 60 points in 4 factories. The admittance matrix was represented by the equivalent circuit composed by six impedances, then the DMZ and the LCL were calculated from the mean value of the impedances. The results showed that the absolute value of DMZ was lower than the characteristic impedance of the PLC transmission line, and the LCL value was similar to the LCL in house environment where a two-phase power distribution system was employed.

Bombyx mori silk fibroin (SF) was successfully used for vascular grafts implanted in rats or dogs. Current transgenic technology can be developed to produce SF with improved properties. In this study, the vascular endothelial growth factor (VEGF) or the repeated fibronectin-derived sequence, TGRGDSPAS, and arginylglycylaspartic acid (RGD) were introduced into the SF heavy chain to improve its properties. A blood compatibility assay was performed to study lactose dehydrogenase (LDH) activity for both transgenic and wild type SF. Growth of human umbilical endothelial cells (HUVECs) showed greater enhancement of cellularization behaviour for the transgenic SF samples (VEGF and RGD) than for the wild type (WT) SF. VEGF SF also showed lower platelet adhesion than the RGD SF and WT SF. An in vivo implantation study supported these in vitro results. In particular, early endothelialisation was observed for VEGF transgenic SF, including the occurrence of native tissue organization at three months after implantation in rat abdominal aorta.

Interest in vascular grafts has recently grown because more patients are undergoing procedures that involve these grafts. However, smaller grafts with diameters

To improve the reproducibility of radiated emission measurement, a very high frequency line impedance stabilization network (VHF-LISN) has been proposed and has been under consideration for standardization into basic measurement standards (CISPR 16-2-3 and CISPR 16-1-4). Since a VHF-LISN can be placed on the ground plane (GP), we thought it was necessary to investigate the effects of placing it. Initially, the effects were investigated by normalized site attenuation (NSA) measurements. The influence of a common-mode absorbing device (CMAD) and an artificial mains network (AMN) were also investigated in the same way for comparison. Then, we created simulation models of antennas and these devices. Both actual measurement results and simulation results demonstrated that the influence of VHF-LISN was smaller than the influence of CMAD or AMN. The results suggest that evaluation of the influence on the NSA of a VHF-LISN placed on the GP is not needed if the evaluation is not required for a CMAD or an AMN.

Characteristics of radiated emission from the three-wire power cable where the power line communication signal was transmitting was studied by using circuit theory. The simple model whose length was 14.4m was used for the investigation, and the radiated emission was calculated and measured. The average deviation between the calculated data and the measured data was -3.6dB and the standard deviation was 3.3dB. The calculation results indicated that the maximum magnetic field strength could be estimated from the maximum common-mode current. The analysis also suggested that the maximum common-mode current of a three-wire cable was less than that of a two-wire cable in many cases.

Electromagnetic field radiated from Power Line Communication (PLC) which was applied to three wires system was examined with Method of Moments (MoM). The influence of the wire configuration and the terminating condition of the third wire was also evaluated. Calculated common mode current and electromagnetic field intensity agreed well with measured results. The calculation results showed that electromagnetic field intensity decreased or didn't change from two wires system when the third wire was connected to the ground.

To improve the correlation of radiated emission measurements between test sites, a very high frequency line impedance stabilization network (VHF -LISN), a coupling/decoupling network for emission measurement of mains (CDNE-M), and a common-mode absorbing device (CMAD) were proposed as the devices that improve inter-site correlation. The result of the international round robin testing (RRT) using two pieces of equipment under test (EUT) has verified an inter-site correlation improvement effect of both EUTs in VHF-LISN and CDNE-M, but the effect varies depending on EUTs in CMAD. As an additional verification of the previous international RRT, we investigated why the effect of VHF-LISN and CMAD was different. Initially, we evaluated the relation between the influence on the common-mode current variation and the impedance value inserted into the protective earth (PE) line by using a CMAD and an artificial EUT. The evaluation result demonstrated that, if the PE line current was reduced by inserting the impedance, the influence due to changes in the termination impedance at the outlet decreases. Based on this result, we evaluated the effects of improvement in inter-site correlation of VHF-LISN and CMAD by changing the PE line current for three piece of EUT. The evaluation result demonstrated that an effect of VHF-LISN did not depended on the PE current, but, in the case of CMAD, almost no effect was gained when the sufficient PE current existed. Because a PE line is directly connected to the frame of EUT in many cases, this result indicates that the device that defines termination impedance at the outlet on the turntable, such as VHF -LISN, is required to improve the inter-site correlation.

The international round robin test (RRT) demonstrated that the site correlation improvement effect of a common-mode absorbing device (CMAD) varies depending on the equipment under test (EUT). This paper investigates the cause. The standard deviation of the common-mode current, when the termination condition was changed at the AC mains cable end, was obtained from the calculation by using 6-port network and the measurement by using the artificial EUT. The results indicated that the standard deviation was reduced when a high impedance was inserted between the EUT's frame and the protective earth (PE) wire. The results, based on the EUT used in RRT, indicated that the standard deviation of radiated emission was reduced by decoupling the PE wire from the frame. In conclusion, since the EUT's frame is directly connected to the PE wire in many cases, the effect of CMAD can be discounted.

This paper verifies the degree of influence that the standardization of mains cable termination condition which is currently proposed with CISPR/SC-I gives to the Standards Compliance Uncertainty (SCU). First of all, we presumed the uncertainty value of the mains cable termination in the radiating emission measurement from the results of Round Robin Test which circulated the same EUT, the same cable termination device, and the same mains cable layout. And then, the radiating emission levels which were calculated considering with the tolerance of the termination impedance were used for presuming the measurement uncertainty when the mains cable was terminated by the device. Finally, the expanded Measurement Instrumentation Uncertainty (MIU) including the uncertainty by AC mains cable terminating condition was considered in calculation. From this result we have proposed this condition shall be included to the MIU.

In regard to the influence of AC mains cable termination on radiated emission, we compared and analyzed the simulation results in single-wire and 3-wire line configuration by round-robin testing with a comb generator and tower PC. The analysis result demonstrates that the deviation with 25-ohm and 150-ohm termination and the deviation with a comb generator and a tower PC using a very high frequency line impedance stabilization network (VHF-LISN) and coupling/decoupling network (CDNE) are nearly equal. Thus, single-wire simulation reflects the result using a comb generator in RRT, and 3-wire simulation reflects the result using a tower PC. Based on these findings, we compared deviations of average values of radiated field strength of the comb generator and tower PC by VHF-LISN and CDNE, with based on “without termination device.” We thereby conclude that the terminating each line with 50 Ω by VHF-LISN is the proper way.

In the emission standard CISPR32 for multimedia equipment (MME), the specification provided for cabling on the reference ground plane (RGP) stipulates that the thickness of the insulation shall not be more than 150 mm. However, the emission standard does not specify a minimum insulation thickness. Therefore, it is assumed that measurements will be conducted at various insulation thicknesses across various test sites. Thus, the cable impedance varies with the degree of coupling with the RGP, which may significantly degrade the reproducibility of measurements. This investigation verifies that varying insulation thickness does impact AC cable-radiated emission. A very high frequency Une impedance stabilization network (VHF-LISN) representing the common-mode impedance of an AC outlet supplying power to the equipment under test (EUT) in the actual test site was used. The test results have verified that the radiated emission changes much at an insulation thickness of 2 mm or less and the change gradually decreases as the thickness increases (5 dB or less at a thickness of 12 mm or more and 2 dB or less at a thickness of 30 mm).

GPBA is a G protein–coupled receptor that is activated by bile acids. Because activation of GPBA leads to increased cAMP levels and secretion of incretins and insulin, GPBA has been proposed as a promising drug target for the treatment of metabolic syndrome. Previously, we have developed a ligand-screening system to identify novel agonists of GPBA by means of a fusion protein of GPBA with G protein stimulatory α subunit (Gsα) and by a [35S]GTPγS-binding assay. To express the GPBA–Gsα fusion protein, transgenic silkworms were employed in this study, and cell membrane fractions were prepared from their fat body or pupae. We applied them to the screening of a chemical library that contains 10,625 compounds from the RIKEN Natural Products Depository (NPDepo). Eventually, a unique partial agonist, GUM2, was successfully identified. Our results indicated that the GPCR–Gα fusion proteins were beneficial for ligand identification and that the transgenic silkworms were useful for large-scale production of GPCRs. In HEK293 cells transiently expressing GPBA, GUM2 showed 50% effective concentration (EC50) of 3.5 ± 2.4 μM and induced GPBA internalization as effectively as did an endogenous agonist, TLC. We also confirmed that GUM2 stimulates insulin secretion in MIN6 cells. Moreover, a single 2 mg/kg dose of GUM2 significantly reduced blood glucose levels in mice during an intraperitoneal glucose tolerance test even though GUM2 is only a partial agonist with a low intrinsic activity. We concluded that GUM2 is a good candidate for research on GPBA signaling under physiological conditions and for the development of GPBA-targeting therapeutic compounds.