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In June 2021, the Ministry of Health, Labor and Welfare approved Delytact Injection as a regenerative medical product for oncolytic virus therapy. The active substance of Delytact Injection is teserpaturev, a genetically engineered herpes simplex virus type 1 (strain F) in which the α47 gene and both copies of the γ34.5 gene have been deleted and the infected cell protein 6 (ICP6) gene has been inactivated by the insertion of the lacZ gene from Escherichia coli. Delytact Injection, when intratumorally administered to patients with malignant glioma, is expected to exert the following effects: (1) the mutant virus selectively replicates in tumor cells and destroys the infected cells through the replication process, exerting a cytocidal effect, and (2) the administration leads to induction of tumor-responsive T cells, which activates antitumor immunity and thus prolongs the survival of patients with malignant glioma. A Japanese phase II study (Study GD01) was conducted in patients with glioblastoma who had residual or recurrent tumors after radiotherapy with concomitant temozolomide. In Study GD01, however, stable disease continued for an extended period in some patients with glioblastoma. Hence, Delytact Injection is expected to be effective to a certain level. In line with this, Delytact Injection has been approved as an option for the treatment of malignant glioma, with one of the 3 approval conditions including conducting a use-results comparison survey and resubmission of the marketing authorization application within the granted time period of 7 years, under the conditional and time-limited approval scheme described in Article 23–26 of Act on Securing Quality, Efficacy and Safety of Products Including Pharmaceuticals and Medical Devices.

Total simulation from vibration of elevator motor to noise at sitting room with anti-vibration measures is confirmed in design stage. This procedure also presents decrease of acoustic noise in sitting room. In this simulation, FEM calculates wave motion, such as wave phase, interference, diffraction and natural frequency mode of sitting room wall. These procedures yield the ration between vibration of elevator motor and acoustic noise in sitting-room.

In July 2017, Japan's Ministry of Health, Labor and Welfare issued a marketing authorization valid throughout Japan for N-(2,6-dimethylphenyl)-N-(2-{[4-(1,2,4-oxadiazol-3-yl)phenyl]amino}-2-oxoethyl)-1,1-dioxothiane-4-carboxamide (amenamevir) for the first time worldwide. The decision was based on the favorable opinion of the Pharmaceuticals and Medical Device Agency (PMDA) recommending a marketing authorization of amenamevir for treatment of herpes zoster (HZ). Amenamevir has a different action mechanism from previously approved synthetic nucleoside compounds for the treatment of HZ including acyclovir, valacyclovir and famciclovir. The usual adult dose is 400 mg amenamevir p.o. once daily for 7 days. The benefit is its ability to cure HZ as well as preventing postherpetic neuralgia. The most common side-effects are increase of urine N-acetyl-β-D-glucosaminidase and α1-microglobulin levels. However, based on the detailed evaluation of the submitted clinical studies, there seems to be no serious safety concerns about amenamevir regarding the kidney of both renally normal and impaired patients. The objective of this article is to summarize the scientific review of the application. The detailed scientific assessment report and product information, including the summary of product characteristics, are available on the PMDA website (www.pmda.go.jp/PmdaSearch/iyakuSearch/).

Tick-borne viruses have emerged recently in many parts of the world, and the discoveries of novel tick-borne viruses have been accelerated by the development of high-throughput sequencing technology. In this study, a cost-efficient small benchtop next-generation sequencer, the Illumina MiniSeq, was used for the RNA virome analysis of questing ticks collected from Hokuriku District, Japan, and assessed for their potential utility in a tick-borne virus surveillance system. We detected two phleboviruses [Kabuto Mountain virus (KAMV) and Okutama tick virus (OKTV)], a coltivirus [Tarumizu tick virus (TarTV)], and a novel iflavirus [Hamaphysalis flava iflavirus (HfIFV)] from tick homogenates and/or cell culture supernatants after virus isolation processes. The number of sequence reads from KAMV and TarTV markedly increased when cell culture supernatants were used, indicating a successful isolation of these viruses. In contrast, OKTV and HfIFV were detected only in tick homogenates but not from cell culture supernatants, suggesting a failure to isolate these viruses. Furthermore, we performed genomic and phylogenetic analyzes of these detected viruses. OKTV and some phleboviruses discovered recently by NGS-based methods were probably deficient in the M genome segment, which are herein proposed as M segment-deficient phlebovirus (MdPV). A phylogenetic analysis of phleboviruses, including MdPV, suggested that Uukuniemi and Kaisodi group viruses and kabutoviruses evolved from an ancestral MdPV, which provides insights into the evolutionary dynamics of phleboviruses as emerging pathogens.

It is well known that the mite Leptotrombidium scutellare carries the pathogen of scrub typhus, Orientia tsutsugamushi. However, our understanding of other bacterial endosymbionts of mites is limited. This study investigated the diversity of the obligate intracellular bacteria carried by L. scutellare using 16S rRNA gene amplicon analysis with next-generation sequencing. The results showed that the detected bacteria were classified into the genera Rickettsia, Wolbachia, and Rickettsiella and an unknown genus of the order Rickettsiales. For further classification of the detected bacteria, a representative read that was most closely related to the assigned taxonomic classification was subjected to homology search and phylogenic analysis. The results showed that some bacteria of the genus Rickettsia were identical or very close to the human pathogens Rickettsia akari, Rickettsia aeschlimannii, Rickettsia felis, and Rickettsia australis. The genetic distance between the genus Wolbachia bacteria in the present study and in previous reports is highly indicative that the bacteria in the present study can be classified as a new taxon of Wolbachia. This study detected obligate intracellular bacteria from unfed mites; thus, the mites did not acquire bacteria from infected animals or any other infectious sources. Finally, the present study demonstrated that various and novel bacterial endosymbionts of mites, in addition to O. tsutsugamushi, might uniquely evolve with the host mites throughout overlapping generations of the mite life cycle. The roles of the bacteria in mites and their pathogenicity should be further examined in studies based on bacterial isolation.

Surface-textured morphology of transparent conductive oxide (TCO) substrates enhances light absorption in Si thin films by scattering and trapping light, which results in an increase in the current density of Si thin film solar cells. However, the highly textured morphology often induces the formation of structural defects within the Si layer, which decreases the photovoltaic performance parameters of solar cells such as the open-circuit voltage (VOC) and fill factor (FF). To overcome this trade-off, we propose a flattened light-scattering TCO substrate based on a strongly light-scattering metal-oxide nanoparticle (NP) layer in conjunction with a surface TCO layer of low surface roughness. Individual layers of ZnO, TiO2, and stacked TiO2/ZnO metal-oxide nanoparticles (NP-TiO2/NP-ZnO), which functioned as a light-scattering layer, were formed between a glass substrate and a low-resistivity Al-doped zinc oxide (AZO) layer to serve as substrates for Si thin film solar cells. After deposition of the AZO film, the nanoparticle AZO substrate demonstrated good flatness and high haze values, which were nearly equivalent to the haze values of the nanoparticle layers before coating by AZO. For thin film hydrogenated amorphous Si (a-Si:H) solar cells fabricated on the stacked AZO/NP-TiO2/NP-ZnO substrate, the short-circuit current increased with no corresponding decrease in the VOC or FF. We attribute this result to an improved spectral response in a wavelength range λ > 500 nm and a decrease in the structural defects within the Si layers.

Fluorescent ubiquitination-based cell cycle indicator (Fucci) technology utilizing the cell cycle-dependent proteolysis of ubiquitin oscillators enables visualization of cell cycle progression in living cells. The Fucci probe consists of two chimeric fluorescent proteins, FucciS/G2/M and FucciG1, which label the nuclei of cells in S/G2/M phase green and those in G1 phase red, respectively. In this study, we generated Fucci transgenic mice and analyzed transgene expression in hematopoietic cells using flow cytometry. The FucciS/G2/M-#474 and FucciG1-#639 mouse lines exhibited high-level transgene expression in most hematopoietic cell populations. The FucciG1-#610 line expressed the transgene at high levels predominantly in the hematopoietic stem cell (HSC) population. Analysis of the HSC (CD34(-)KSL: CD34(-/low)c-Kit(+)Sca-1(+)lineage marker(-)) population in the transgenic mice expressing both FucciS/G2/M and FucciG1 (#474/#610) confirmed that more than 95% of the cells were in G0/G1 phase, although the FucciG1(red) intensity was heterogeneous. An in vivo competitive repopulation assay revealed that repopulating activity resided largely in the FucciG1(red)(high) fraction of CD34(-)KSL cells. Thus, the CD34(-)KSL HSC population can be further purified on the basis of the Fucci intensity.

During the course of tick-borne virus surveillance in Japan, three independent isolates of probably the same virus were obtained from three geographically distant populations of the hard tick Haemaphysalis flava. Genome analyses of the three isolates demonstrated that they were closely related but distinct strains of a novel virus, designated Tarumizu tick virus (TarTV), which has a genome of 12 double-stranded RNA segments. The development of the virus-induced cytopathic effects on BHK cells significantly varied according to virus strains. Ten out of 12 segments of TarTV appeared to encode putative orthologs or functional equivalents of viral proteins of Colorado tick fever virus (CTFV) and Eyach virus, suggesting that TarTV is the third member of the genus Coltivirus in the family Reoviridae. This was supported by the facts that the 5'- and 3'-terminal consensus sequences of coltivirus genomes were found also in TarTV genome, and segment 9 of TarTV had sequence and structural features that may mediate a stop codon read-through as observed in that of CTFV. However, segment 7 and 10 of TarTV had no significant sequence similarities to any other proteins of known coltiviruses. Electron microscopic analysis demonstrated that TarTV particle had a non-enveloped bilayer icosahedral structure, and viral inclusion bodies were formed in infected cells. TarTV could infect and replicate in several mammalian cell lines tested, but show no clinical symptoms in intracerebrally inoculated mice. Taken together, our findings provide new insights into genetic diversity and evolution of the genus Coltivirus.

To improve the light-scattering capacity of transparent conductive oxide (TCO) films without increasing in surface roughness, we formed a stacked nanoparticle layers of ZnO (NP-ZnO) and TiO2 (NP-TiO2), which serve as light-scattering and surface-modifying layers, respectively, between the glass substrate and low-resistive TCO layers. The stacked TCO/NP/glass (NP-TCO) substrate indicated strong light-scattering capacity, with a relatively low surface root mean roughness of approximately 10nm. In addition, the haze value of NP-TCO substrates increased with an increase in the component particle diameter of the underlying NP-ZnO layers from about 20% (33nm) to 40% (96nm) at a wavelength of 550nm. [doi:10.2320/matertrans.M2014208]

Thin film Si solar cells based on hydrogenated amorphous Si and hydrogenated microcrystalline Si have been considered to have a reduced manufacturing cost compared with crystal type Si solar cells due to their reduced use of Si materials. However, the conversion efficiency of thin film Si solar cells is much lower than that of crystal Si solar cells owing to their lower photo absorption in the near infrared region which can be attributed to their indirect-transition type absorption and thin Si layer thickness. In order to increase in the conversion efficiency of thin film Si solar cells, improvement in the optical path length in the near infrared region is necessary. In order to confine the light and thereby increase the optical path length within the solar cells, a textured morphology has been formed on a transparent

The intake of dust and dirt contained outside the air into the motor while driving causes the maintenance of dismantling and clean-up operation once every three years. Moreover, excessive acoustic noise during high-speed operation is produced by the cooling fan on the rotor. Totally enclosed airtight motor was developed not only to deal with the dust-intake problem but also to reduce acoustic noise. This motor eliminates the requirement of periodical dismantling and clean-up operation. Excessive noise of internal cooling fan was decreased by newly developed uneven pitch blade fan. Further, traction motor without external fan was developed by thermofluid simulation. Acoustic noise and temperature rise of these motor were measured and compared.

Mitochondrial energy production is involved in various cellular processes. Here we show that ATP content is significantly increased in lineage-restricted progenitor cells compared with hematopoietic stem and progenitor cells (HSPCs) or more differentiated cells. Transplantation analysis using a mouse model of mitochondrial disease revealed that mitochondrial respiration defects resulted in a significant decrease in the total number and repopulating activity of bone marrow cells, although the number of HSPCs increased. The proliferative activity of HSPCs and lineage-restricted progenitor cells was not impaired by reduction of ATP content and there seems to be no associated increase in reactive oxygen species levels and apoptosis. Our findings indicate that mitochondrial respiration defects modulate HSPC commitment/differentiation into lineage-restricted progenitor cells.

Contamination of hands by soil-transmitted helminth eggs was investigated in a small village located in the suburbs of Hanoi, Vietnam. Thirty-three households, consisting of one to eight members, were selected in the village. In addition, 130 school children, including 80 pupils from primary school grade 1 and 50 students from secondary school grade 8, were selected for the survey. A total of 285 villagers were subjected to the collection of hand-wash samples either once or twice during the study. Parasite eggs were found in 37 (13.0%) samples from 21 males and 16 females aged between 2 and 72 years old. One person was positive in both the rainy and dry season. Eggs of seven parasite species were detected; Enterovius. vermicularis (8.4%), Ascaris sp. (2.1%), Trichuris sp. (1.1%), Ascaridia galli (0.7%), Taenia sp. (0.7%), Capillaria sp. (0.4%) and Toxocara sp. (0.4%). A total of 249 villagers were subjected to collection of nail samples either once or twice during the study. Parasite eggs were found in 10 (4.0%) samples from 5 males and 5 females aged between 6 and 46 years old. Six people were also positive on examination of hand-wash samples. Eggs of four parasite species were detected; E.vermicularis (2.0%), Ascaris sp. (0.8%), Trichuris sp.(0.8%) and Toxocara sp. (0.4%). The present study indicates that the infection route by hands plays an important role in the transmission of the soil-transmitted helminth., Tropical Medicine and Health, 38(2), pp.75-79; 2010

Most electromagnetic acoustic noise of induction motors is generated when the mechanical natural frequencies of the stator coincide with or are close to the frequencies of magnetomotive forces. In order to avoid this, it is necessary to determine the motor's mechanical natural frequencies by calculation or simulation. Variation of natural frequency from yoke steel ring to motor has been studied experimentally, analytically and by structural finite-element method analysis. It thus became clear that mechanical natural frequencies increased in number and natural frequencies gradually decreased from simple yoke steel ring to motor.

症例は70歳，男性．腹痛と発熱を主訴に受診し，腹部CTで左側腹腔内に多房性の腫瘤を認めた．腹腔内膿瘍の診断で抗生剤を投与し，膿瘍の縮小と症状の改善を認めたため，退院した．しかし，2カ月後に腹痛と発熱が再燃し，膿瘍が増大したため，手術を施行した．手術所見では壁側・臓側腹膜に多数の白色結節ならびに高度な癒着を認め，大網および腸間膜組織内の肉芽腫性病変を切除した．術後の病理診断でウエステルマン肺吸虫が原因であると判明し，問診にてイノシシの生肉の摂取歴が確認された．術後はプラジカンテルの内服加療を行った．腹腔内膿瘍の原因として，憩室穿孔，魚骨による穿孔など様々であるが，寄生虫疾患も念頭に置き，鑑別診断を行う必要がある．

Recently, there has been increasing demand for quiet motors, and the same trend has been observed in the case of induction motors. In induction motors, electromagnetic noise is sometimes the predominant acoustic noise. In small motors, the major cause of vibration and noise is electromagnetic forces resulting from the combination of harmonic fluxes in the air gap. In this study, the spatial distribution of fundamental and harmonic time electromagnetic forces was studied by using search coils, by performing FEM analysis, and by using conventional equations. In a four-pole 2.2kW motor, harmonic electromagnetic forces were measured using 36 search coils on the inner surface of the stator teeth, and the spatial distribution of electromagnetic forces was obtained at each time harmonic frequency. Spatial distribution was also analyzed by FEM, and the results were analytically validated by using conventional equations. On the basis of these analyses, the spatial distribution of electromagnetic forces for various time harmonics was confirmed. These results can be used in the design and development of quiet motors.

Closed rotor slots are widely employed in low-power squirrel-cage induction motors with die-cast aluminum cage rotors. Die-cast aluminum cages with closed rotor slots can be manufactured commercially. They help reduce flux pulsation in air gaps, attenuate acoustic noises, and achieve high efficiency. However, it is difficult to calculate bridge inductance of a closed rotor slot accurately because the main flux passes through the bridge and iron saturation can be achieved depending upon the bar current.In this study, bridge inductance was investigated by using a search coil and by FEM analysis and conventional equations. The bridge flux density and the bridge linkage flux were measured by using 4P-0.75kW motor with closed rotor slots, and the bridge inductance was calculated as a function of rotor bar current. The bridge inductance was also analyzed by FEM, and the results were analytically checked by using the calculated conventional equations. From these analyses, it is seen that the measured values of the bridge inductance are in good agreement with the values calculated by FEM and conventional methods. It is verified that the bridge inductance shows a trend similar to that of the μ-H curve of the rotor steel sheet.

Contamination of water and air by soil-transmitted helminth eggs was investigated in a small village located in the suburbs of Hanoi, Vietnam. Water samples were collected from 29 households, two schools, two kindergartens, one restaurant, three ponds and 23 ditch sites during the rainy season. Water samples were also collected at the same places, except for one household and one restaurant, during the dry season. The water samples collected from households, schools, kindergartens and restaurant were comprised of well-water and rain-water. These samples included both water filtrated with sand and gravel and non-filtrated water. Two-liter water samples were examined for helminth eggs by either a centrifugation or flotation method. The contamination of air by helminth eggs was assessed by the method of Kroeger et al. (1992). Eggs in air were trapped on adhesive tapes hanging in rooms and in the area around 29 houses, two schools, two kindergartens, one restaurant and 18 utility poles. Out of 63 water samples collected from households in the rainy season, helminth eggs were found in four water samples; one from non-filtrated well-water and three from filtrated well-water samples. The one non-filtrated water sample contained six eggs of Toxocara sp., while the three filtrated water samples contained one egg each of Trichuris sp., Trichiuris sp. and Taenia sp. No eggs were found in the water samples collected from schools, kindergartens or the restaurant in the rainy season. All water samples collected from ponds and ditches in the rainy season contained many helminth eggs. The eggs found were Ascaris sp., Trichuris sp., Toxocara sp., Ascaridia galli, hookworm, Taenia sp. and Fasciola sp. Examination of the adhesive tapes hanging in the air showed that four sites were contaminated by helminth eggs, i. e. one site near the house, two sites near the school and one site at a utility pole. The species of eggs found were Trichuris sp., Ascaridia galli and Taenia sp. The number of eggs found on tapes was only one or two. In the dry season, a few samples of well-water and rain-water collected from the residential area were contaminated with helminth eggs, and all samples collected from ponds and ditches contained many eggs of various species similar to those collected in the rainy season. The present study clearly indicates that, in our study area, the villagers were subject to infection from soil-transmitted helminthes directly and indirectly through water., Tropical Medicine and Health, vol.37(2), pp.55-61; 2009

Unsteady control effect of non-thermal plasma on leading edge separation flow was investigated experimentally. Wind tunnel experiment was done using a NACA0015 airfoil of 9 cm chord length of c under Reynolds number condition of Re=U∞c/ν=1.2×105, where U∞ : flow velocity, ν : kinematic viscosity. A pulse modulated mode with a fundamental frequency of 5 kHz was adapted to apply voltage to dielectric-barrier discharge electrodes which were mounted on the leading edge of the airfoil. First, effect of pulse modulation frequency on separation control was investigated. Second, effect of duty cycle was studied. Finally, FFT characteristic of wake flow under the separation control flow was discussed. An optimum frequency of f corresponds to fc/U∞=0.47 and 10% duty (discharge power of 0.18 W) was found to exist for unsteady excitation of the leading edge separation. FFT analysis result indicates that this optimum unsteady control of the dielectric-barrier discharge has a role to organize coherent structure of the separation flow.

A better understanding of the biology of cultured hematopoietic stem cells (HSCs) is required to achieve ex vivo expansion of HSCs. In this study, clonal analysis of the surface phenotype and repopulating activity of ex vivo-expanded murine HSCs was performed. After 7 days of culture with stem cell factor, thrombopoietin, fibroblast growth factor-1, and insulin-like growth factor-2, single CD34−/lowc-Kit+Sca-1+lineage marker− (CD34−KSL) cells gave rise to various numbers of cells. The proportion of KSL cells decreased with increasing number of expanded cells. Transplantation studies revealed that the progeny containing a higher percentage of KSL cells tended to have enhanced repopulating potential. We also found that CD48 was heterogeneously expressed in the KSL cell population after culture. Repopulating activity resided only in the CD48−KSL cell population, which had a relatively long intermitotic interval. Microarray analysis showed surprisingly few differences in gene expression between cultured CD48−KSL cells (cycling HSCs) and CD48+KSL cells (cycling non-HSCs) compared with freshly isolated CD34−KSL cells (quiescent HSCs), suggesting that the maintenance of stem cell activity is controlled by a relatively small number of genes. These findings should lead to a better understanding of ex vivo-expanded HSCs. Disclosure of potential conflicts of interest is found at the end of this article.

Although cloning animals by somatic cell nuclear transfer is generally inefficient, the use of certain nuclear donor cell types may significantly improve or deteriorate outcomes. We evaluated whether two multipotent stem cell lines produced in vitro—neural stem cells (NSCs) and mesenchymal stem cells (MSCs)—could serve as nuclear donors for nuclear transfer cloning. Most (76%) NSC-derived embryos survived the two-cell–to–four-cell transition, the stage when the major zygotic gene activation occurs. Consistent with this observation, the expression patterns of zygotically active genes were better in NSC-derived embryos than in fibroblast clone embryos, which arrested at the two-cell stage more frequently. Embryo transfer experiments demonstrated that at least some of these NSC embryos had the ability to develop to term fetuses (1.6%, 3/189). In contrast, embryos reconstructed using MSCs showed a low rate of in vitro development and never underwent implantation in vivo. Chromosomal analysis of the donor MSCs revealed very frequent aneuploidy, which probably impaired the potential for development of their derived clones. This is the first demonstration that tissue-specific multipotent stem cells produced in vitro can serve as donors of nuclei for cloning mice; however, these cells may be prone to chromosomal aberrations, leading to high embryonic death rates. We found previously that hematopoietic stem cells (HSCs) are very inefficient donor cells because of their failure to activate the genes essential for embryonic development. Taken together, our data led us to conclude that tissue-specific stem cells in mice, namely NSCs, MSCs, and HSCs, exhibited marked variations in the ability to produce cloned offspring and that this ability varies according to both the epigenetic and genetic status of the original genomes. Disclosure of potential conflicts of interest is found at the end of this article.

Environmental concerns have increased demand for induction motors with low noise characteristics. Electromagnetic noise has been a particularly concern. Relation of electromagnetic noise and natural frequencies has been studied for more than twenty years. However, a new phenomenon has arisen, in which motor noise changes with increase in motor temperature. In this study, the relation-ship between electromagnetic noise and temperature was analyzed quantitatively. It was found the relation of electromagnetic noise and temperature as follows. In temperature 20-70°C, noise level does not varies, but in temperature 70-140°C noise level decreases drastically by 6 dB (A) at first and then increases by 3 dB (A). Natural frequencies of 273 Hz and 350 Hz appear at 20°C, and two natural frequencies unite at 70-140°C in the experiments. A two-degrees of freedom system with core and coil end considering temperature effects was used for calculation of the natural frequency. These calculated values agreed with experimental results. The relation between variation of the natural frequency and temperature in electromagnetic noise was analyzed and the cause of noise variation with temperature was clarified.

In general, cloning undifferentiated preimplantation embryos (blastomeres) or embryonic stem cells is more efficient than cloning differentiated somatic cells. Therefore, there has been an assumption that tissue-specific stem cells might serve as efficient donors for nuclear transfer because of the undifferentiated state of their genome. Here, we show that this is not the case with adult hematopoietic stem cells (HSCs). Although we have demonstrated for the first time that mouse HSCs can be cloned to generate offspring, the birth rates (0-0.7%) were lowest among the clones tested (cumulus, immature Sertoli and fibroblast cells). Only 6% of reconstructed embryos reached the morula or blastocyst stage in vitro (versus 46% for cumulus clones; P

患者は70歳代の男性.腹痛を主訴にS状結腸癌の診断で腹腔鏡補助下大腸切除術の目的で入院.術前の血液検査に異常はなかった.腹腔鏡観察で,下腹部を中心に壁側・臓側腹膜に多数の白色結節ならびに高度な腹腔内癒着を認めたが,鏡視下に根治手術を施行した.術後の病理診断で腹腔内の結節は肺吸虫卵によるものであることが判明し,その後の問診でイノシシの生肉の摂取歴も確認でき,腹腔内肺吸虫症と診断された.腹部外科領域では,寄生虫疾患に遭遇することが少ないが,稀ではあるものの寄生虫疾患も念頭において日常診療にあたる必要があると思われた.

A quiet induction motor is strongly demanded today. Electromagnetic factors are a main cause of vibration and acoustic noise in a small induction motor. Electromagnetic forces and magnetostrictive forces are considered as the origin of electromagnetic vibration and noise. In this paper, magnetostrictive vibration of a ring of electrical steel sheets was simulated by the mechanical finite element method. Magnetostriction was assumed as external forces and they were added at each node of the meshed ring. Resonant frequency and the mode of the ring were calculated. In the steel sheet ring excited by a PWM voltage source inverter, the frequency spectrum of vibration of ring was measured and compared with the calculated results. It was confirmed that these procedures simulated magnetostriction behavior of electrical steel sheets. Furthermore, the electromagnetic forces of a small induction motor were calculated and compared with the magnetostriction data. It became clear that electromagnetic vibration was affected by the magnetostriction of steel. These results will be useful in the reduction of acoustic noise and the development of quiet motors. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(2): 8–13, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10338

Cercariometry provided information on diurnal fluctuation, seasonal and spatial distribution of cercariae in the suitable natural water bodies. There was an apparent mismatch between the results of cercariometry and snail sampling. Water, which cercariometry showed to contain cercariae was potentially infective, although the resultant worm load of sentinel rodents may not bear a linear relationship with cercarial density. Cercariometry has some weakness in practices and analysis of data, however, it provides the valuable information on the active transmission sites of schistosomiasis.

There has been an increasing demand for a quiet induction motor. Electromagnetic noise is jarring to the ear. Most offensive electromagnetic noise is generated when the natural frequencies of the stator coincide with or are close to the frequencies of the magnetomotive forces. In this paper, electromagnetic noise is calculated by boundary element method (BEM) program using the electromagnetic forces of Maxwell stress. The natural frequency and behavior of the stator are calculated by mechanical finite element method (FEM), considering the contact between stator core and frame. Spring elements are introduced between the stator frame and the stacked core. Vibration is calculated by mechanical FEM. Calculated and experimental noise level were within 3 dB(A) at 1200 and 4080 Hz.