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Topological photonics mimicking topological insulators has recently attracted considerable attention. The Su–Schrieffer–Heeger (SSH) model, which is a fundamental topological system, has been experimentally demonstrated in many photonic systems owing to its simplicity. In particular, a zigzag chain, which is described by the SSH model, shows intriguing functionality such as polarization-dependent switching of topological edge states. To date, the far-field imaging of topological edge states in plasmonic chains has not been reported because of the constraint imposed by the diffraction limit. In this study, we experimentally observed the photonic topological edge states of zigzag plasmonic chains composed of metal nanodiscs in the optical region through far-field imaging. Using a chain longer than the diffraction limit, light scattering from the two edges of the zigzag chains was resolved. In the case of such a long chain, it was revealed that tiny gaps of several nanometers between the discs, which are difficult to fabricate, are necessary. Therefore, we propose connected chains and investigate the effect of the shape of the connected part, which reveals that similar topological edge states can be obtained even in the connected chains. The polarization dependence of edge-state imaging showed switching of the systems in trivial and topological phases in the same zigzag chain. Far-field observations serve as an easy and effective tool for the investigation and application of photonic topological edge states.

The antigenic variant QX-like infectious bronchitis virus (IBV) is endemic in several countries. In Japan, the QX-like genotype is classified as the JP-III genotype based on the partial S1 gene and as the GI-19 genotype based on the complete S1 gene. This study showed that QX-like IBVs and JP-III IBVs can be identified based on the amino acid polymorphism of the S1 glycoprotein. Furthermore, genetic analysis of several IBV field strains detected in commercial broiler farms across the Kyushu area in 2020 revealed Japanese QX-like IBVs, which are highly homologous to the QX-like IBVs recently detected in China and South Korea. Herein, QX-like IBV field strains were isolated for evaluating commercial vaccine efficacy in our future studies.

A focused ion beam (FIB) can precisely mill samples and freely form any nanostructure even on surfaces with curvature, like a nanowire surface, which are difficult to implement by using conventional fabrication techniques, e.g. electron beam lithography. Thus, this tool is promising for nanofabrication; however, fabrication damage and contamination are critical issues, which deteriorate optical properties. In this work, we investigated the protective performance of Al2O3 against the FIB process (especially by a gallium ion). Nanowires were coated with Al2O3 as a hard mask to protect them from damage during FIB nanofabrication. To estimate the protective performance, their emission properties by photoluminescence measurement and time-resolved spectroscopy were compared with and without Al2O3 coating conditions. From the results, we confirmed that the Al2O3 coating protects the nanowires. In addition, the nanowires also showed lasing behavior even after FIB processing had been carried out to implement nanostructures. This indicates that their optical properties are well maintained. Thus, our study proves the usefulness of FIBs for future nanofabrication.

Various reports demonstrated that valley photonic-crystal waveguides without inversion symmetry support high transmission in 120-degree sharp bends, whose origin, however, has not been clarified yet. Here, we find that the type of waveguide interfaces dominates this phenomenon instead of the existence of the broken inversion symmetry.

All-optical switches have attracted attention because they can potentially overcome the speed limitation of electric switches. However, ultrafast, energy-efficient all-optical switches have been challenging to realize due to the intrinsically small optical nonlinearity in existing materials. As a solution, we propose graphene-loaded deep-subwavelength plasmonic waveguides (30 nm x 20 nm). Thanks to extreme light confinement, we have significantly enhanced optical nonlinear absorption in graphene, and achieved ultrafast all-optical switching with a switching energy of 35 fJ and a switching time of 260 fs. The switching energy is four orders of magnitudes smaller than that in previous graphene-based devices and is the smallest value ever reported for any all-optical switch operating at a few picoseconds or less. This device can be efficiently connected to conventional Si waveguides and employed in Si photonic integrated circuits. We believe that this graphene-based device will pave the way towards on-chip ultrafast and energy-efficient photonic processing., 28 pages, 5 figures

We have experimentally demonstrated a new formation mechanism of off-Γ bound states in the continuum (BICs), which are generated by a simple symmetry breaking of trivial at-Γ BICs in photonic crystals.

Graphene’s ultrafast carrier response enables ultrafast device operation, but its thinness makes graphene devices large and energy consuming. Introducing plasmonic nanostructures overcomes this problem and makes it possible to develop ultrafast, energy-efficient all- optical switches.

Plants are often exposed not only to short-term (S-) heat stress but also to diurnal long-term (L-) heat stress over several consecutive days; nevertheless, most previous studies of heat tolerance have used S-heat stress, such as 42 °C for 30–60 min, for evaluation. Yet the mechanisms underlying L-heat tolerance remain poorly understood. Here we found that hydrogen peroxide (H2O2) in Arabidopsis thaliana plants increased time-dependently under L-heat stress (37 °C, 5 days) but not under S-heat stress (42 °C, 40 min). To reveal the contribution of reactive oxygen species (ROS) scavenging to heat tolerance, we evaluated the heat tolerance of ROS mutants. Only cat2 mutants, in which catalase (CAT) activity is defective, were hypersensitive to L-heat stress, but they were S-heat tolerant. We further revealed that (1) CAT2 was induced by L-heat stress but not by S-heat stress; (2) H2O2 accumulated highly in cat2 under L-heat stress, but not in cat1, cat3, or wild type; and (3) CAT activity was significantly reduced in cat2 under both normal and L-heat conditions. These results suggest that ROS scavenging is responsible for L-heat tolerance, and CAT2 plays a crucial role. On the other hand, since overexpression of CAT2 in wild-type plants did not enhance L-heat tolerance, CAT2 activity is necessary but insufficient for increasing L-heat tolerance.

Purpose During the implantation period, the uterus goes through many complex, orchestrated changes, including alterations of the glycocalyx that are due to sialylation, sulfation, and fucosylation. A previous mouse study showed that the in vivo intrauterine oxidation‐reduction potential (ORP) aided in determining the alterations in the uterine endometrium that are suitable for implantation and for evaluating prospective uterine receptivity, while the in vivo intrauterine pH did not. It was assessed if the in vivo intrauterine ORP could be a useful parameter to predict pregnancy in women. Methods A prospective cohort study was conducted for patients who had received a frozen‐thawed single embryo transfer in a programmed, hormonally controlled cycle. The in vivo intrauterine ORP was measured 3 times during the treatment cycle, at cycle days 9‐10, 1 day before progesterone administration and immediately before the embryo transfer. Results The amount of in vivo intrauterine ORP at 9‐10 days after the start of menstrual bleeding was significantly lower in the pregnant group than in the non‐pregnant group. A receiver‐operator characteristic curve analysis of the intrauterine ORP as a predictor of non‐conception showed an area under the curve of 0.80. Conclusion The in vivo intrauterine ORP could be a useful parameter to predict pregnancy for the frozen‐thawed embryo transfer treatment cycle.

A Si-Al plasmonic waveguide enables detection of 1550-nm light by internal photoemission and two-photon absorption. We achieve a differential responsivity of 25 mA/W including 6-dB photonic-plasmonic coupling loss and eye openings with over 40-Gbit/s signals.

We have demonstrated ultracompact all-optical modulators by deep-subwavelength graphene-loaded plasmonic waveguides (60 × 40 nm2), and achieved an ultrafast response time (2.2 ps) with a substantially small consumption energy (155 fJ) for the first time.

Here we demonstrate the combination of a semiconductor nanowire and a plasmonic bowtie nanoantenna. A subwavelength InP nanowire was placed precisely in the middle of the nanogap of a gold bowtie nanoantenna with a nanomanipulator installed in a focused ion beam system. We observed a significantly large enhancement (by a factor of 110) of the photoluminescence intensity from this coupled system when the excitation wavelength was at the plasmonic resonance with its polarization parallel to the nanoantenna. Moreover, simulation results revealed that this large enhancement was caused by an interesting interplay between the plasmonic resonance of the nanoantenna and the breakdown of the field suppression effect in the subwavelength nanowire. Our results show that the combination of a nanowire and a nanoantenna gives us a new degree of freedom to design light-matter interactions on a nanoscale.

A plasmonic waveguide with a deep-subwavelength Si core is integrated with a Si photonic waveguide. By utilizing horizontal Al-Si-Al structure, we obtained a 4-dB/μm propagation loss with a 60 × 60 nm2 surface-oxidized Si core.

Isolated sphenoid sinusitis is rare and difficult to diagnose. The difficulty arises because it is located in the deepest part of the nasal sinuses and the associated inflammation does not lead to typical symptoms of sinusitis. There are many important structures in the vicinity of the sphenoid sinus: the internal carotid artery, cavernous sinus and cranial nerves. Therefore, sphenoid sinusitis causes severe complications. From January 2003 to December 2007, we encountered 15 patients with isolated sphenoid sinusitis. Its incidence in all sinus diseases is 2.2%. Many patients complain of headaches, and they often visit neurologists or neurosurgeons. The pathological spectrum included 10 cases of bacterial sinusitis (5 acute sinusitis, 3 chronic sinusitis and 2 asymptomatic sinusitis), 3 fungal sinusitis, 1 mucocele and 1 retention cyst. When we diagnose isolated sphenoid sinusitis, CT and endoscopy are essential. CT becomes a more useful tool for performing a differential diagnosis when we independently change the window height and width. The endoscopic findings regarding draining from the sphenoethmoidal recess may indicate the severity of inflammation. A detailed observation with CT and endoscopy is the most important to accurately diagnose the pathology of isolated sphenoid sinusitis.

Cluster computers applying personal computers (PC) to their processing nodes have been widely used as parallel computational platforms due to the improvements of cost/performance ratio. In order to achieve higher performance of a cluster computer, it is important to be considered not only an approach to improve the network performance but also the one to overlap computation with communication. To confirm the validity of the latter approach, we are developing the Maestro2 cluster network which is composed of general-purpose processors and dedicated communication hardware tightly coupled with those processors. This paper describes a design and implementation of a communication library of a message passing system, called MMP, over the Maestro2 cluster network. On MMP, the processor on the Maestro cluster network controls the hardware and processes almost all communication steps such as for sending/receiving messages and a synchronization among processing units. According to an experimental evaluation, this paper shows that MMP achieves higher throughput than the conventional communication method that is processed by a host processor. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 109–121, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20411

We report a rare case of first and second branchial arch syndrome with fistula originated from the first pharyngeal pouch. A 10-day-old female was referred to our clinic with a complaint of left microtia with fistula at the mandibular angle. On preoperative examinations, X-ray with angiography flexible wire inserted into the fistula and computed tomography with contrast enhancement of the fistula revealed that the fistula was connected to the middle ear cavity. Fistulectomy was performed at the age of 7. Pathological examinations demonstrated that the fistula consisted of a single layer of cylindrical epithelium, suggesting that it originated from the endoderm. Based on surgical, imaging, and pathological findings, the fistula originated from first pharyngeal pouch. Preoperative X-ray with angiography flexible wire inserted into the fistula and the computed tomography with contrast enhancement of the fistula were useful for planning operation.

The horizontal transmission ability of fowl adenovirus (FAV) serotype 1 99ZH strain, isolated from chickens exhibiting gizzard erosion, was investigated. Twelve 13-day-old specific pathogen-free chickens were inoculated orally with 10(6) TCID(50)/0.05 ml of the strain. An in-pen contact group (chickens in the same pen with inoculated chickens), hedge contact group (chickens in a pen connected with pens housing inoculated chickens), non-contact group (chickens in a separate pen placed at a distance of 70 cm from the connected pens), human exposure group (chickens in the next room and attended last every day) and negative control group were examined. Each group consisted of 11 or 12 uninoculated chickens. Gizzard lesions were grossly or histologically observed from 10 days after exposure (DAE) in the in-pen contact group, and from 15 DAE in the hedge contact and non-contact groups. The FAV gene was detected by polymerase chain reaction performed on cloacal swabs taken on 5 and 13 DAE from chickens in both contact groups, and on 20 and 26 DAE from those in the non-contact group. Serum neutralizing antibodies against FAV serotype 1 were detected in chickens from 13 and 26 DAE in both contact groups and in the non-contact group, respectively. In the human exposure and negative control groups, no infection was observed. We conclude that FAV-99ZH strain spreads rapidly through direct contact with inoculated chickens, and slowly through non-contact transmission, and that adenoviral gizzard erosion is reproduced by this horizontal transmission.

We achieved three-dimensional mode conversion between a Si-wire waveguide and a deep sub-λ plasmonic slot waveguide (60 χ 50 nm2) for the first time. The coupling loss was only about 2 dB.

Cluster computers became the vehicle of choice to build high performance computing environments. To fully exploit the computing power of these environments, technologies for high performance networks and protocols have to be applied, since the communication patterns of parallel applications running on clusters demand low latency and high throughput. Our previous work identifies the main drawbacks of conventional network technologies, and proposed some techniques to solve them within a new network solution called Maestro. This paper describes not only the architecture and the evaluation platform of the Maestro2, but also the technologies introduced for enhancing the performance of the original Maestro framework. Novel techniques are proposed at the link layer and at the switching level, and its design and implementation in the Maestro2 is discussed: continuous network burst and out-of-order switching. Moreover, a specialized communication library has been developed to take full advantage of these new techniques for implementing high speed cluster networks based on the Maestro2 environment. Experimental results clearly show that the new proposed techniques provide significant improvements, both in terms of latency and throughput, which are essential to efficient cluster computing.

The fiber gene sequence and pathogenicity of the serotype-1 fowl adenovirus (FAdV-1) isolated from gizzard erosions and from clinically normal chickens were compared among isolates. The FAdV-99ZH strain, which induced gizzard erosions, had a nucleotide sequence of the long fiber gene that was different from that of the Ote strain, which did not induce gizzard erosions. The differences could be distinguished by use of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The long fiber gene of 16 FAdV-1 isolates from gizzard erosions and 10 FAdV-1 isolates from the feces of clinically normal chickens was examined by use of PCR-RFLP analysis. All 16 FAdV-1 isolates from gizzard erosions had the same restriction patterns as those of strain 99ZH; however, 10 FAdV-1 isolates from normal chickens were classified into 3 groups. Specific-pathogen-free (SPF) chickens were inoculated orally with 2 FAdV-1 isolates from gizzard erosions or 3 FAdV-1 isolates from clinically normal chickens to determine the pathogenicity of each strain. Two of 2 FAdV-1 isolates from gizzard erosions induced gizzard erosions. Two of 3 FAdV-1 isolates from normal chickens had the same PCR-RFLP patterns as those of the Ote strain, but did not induce any gizzard erosions. However, 1 FAdV-1 isolate from clinically normal chickens had the same PCR-RFLP pattern as that of strain 99ZH and induced gizzard erosions. These results indicate that there are FAdV-1 strains that have different pathogenicity; one strain induces gizzard erosions, and the other does not. Use of PCR-RFLP analysis of long fiber genes may be able to distinguish between these two strains.

An outbreak of subcutaneous tumors in young layer chickens in a flock in Japan was investigated. Tumors appeared as extensive swelling or bulbous protrusions of the integument and were observed in the head or wing of chickens approximately 9 wk old, with a prevalence of 0.4% (157 of 42,000) in the affected flock. Histologically, two types of tumor were observed: myxoma containing abundant hyaluronic acid and neurofibroma with hyperplasia of the Herbst corpuscles. Ultrastructurally, type C retroviruses, such as viral particles, were found in the tumors. The tumors were specifically stained by immunohistochemistry using monoclonal antibodies against the subgroup A avian leukosis/sarcoma virus (ALSV) and yielded a positive reaction to primers specific for subgroup A ALSV by reverse transcriptase-polymerase chain reaction assay. The virus was isolated from the tumors. Seventeen of 20 clinically normal chickens in the affected flock showed antibodies against ALSV. These results suggest that subcutaneous tumors are associated with subgroup A ALSV infection.

Dual infection of pigs with swine influenza virus (SIV) and Mycoplasma hyopneumoniae was carried out to compare the clinical and pathological effects of dual infection in caesarian derived and colostrums deprived (CDCD) pigs, with that of a single infection with M. hyopneumoniae. In Experiment 1, 40-day-old CDCD pigs were inoculated only with SIV (A/Sw/Hok/2/81, H1N1). The virus was isolated from nasal swabs for 5-6 days. None of these pigs showed clinical signs of infection throughout the experimental period. These results suggested that this strain can infect pigs but is only slightly pathogenic when it is inoculated singly to a CDCD pig. In Experiment 2, 60-day-old CDCD pigs were inoculated with M. hyopneumoniae and then were inoculated with SIV (A/Sw/Hok/2/81) at 1 week (MHYO-7d-SIV-7d group) or 3 weeks (MHYO-21d-SIV-7d group) after M. hyopneumoniae inoculation. Macroscopically, dark red-to-purple lung lesions were observed in all of pigs at 14 or 28 days post-inoculation. Percentages of dark red-to-purple lung lesions in dual infection groups (MHYO-7d-SIV-7d group: 18.7 +/- 4.2%, MHYO-21d-SIV-7d group: 23.0 +/- 8.0%) were significantly (P < 0.05) increased compared to those of each control group in which pigs were inoculated only with M. hyopneumoniae (MHYO-14d group: 4.7 +/- 2.9%, MHYO-28 group: 3.3 +/- 2.4%). Microscopically, bronchial epithelial lesions (epithelial disruption, degeneration, hyperplasia and formation of microabscess) were frequently observed in dark red-to-purple lung lesions of only the dual infection groups. These results demonstrate that the lung lesion of pigs inoculated with M. hyopneumoniae and SIV is more severe than that of pigs inoculated only with M. hyopneumoniae.

The pathogenicity of serotype 8 fowl adenovirus (FAV), isolated from gizzard erosions of slaughtered broiler chickens, was investigated. In experiment 1, 29 5-day-old specific-pathogen-free (SPF) chickens were inoculated with the isolates of serotype 8 FAV, M013 (group 1) or G0054 (group 2) strain, via an oral route. There were no clinical signs in any of chickens after inoculation, and mild gizzard erosions were observed macroscopically and microscopically in three inoculated chickens of group 2. FAV was recovered from gizzards and rectums but was not recovered from pancreas and livers from chickens in both inoculated groups. In experiment 2, 27 1-day-old SPF chickens were inoculated with the G0054 strain by intramuscular route. Five, 6, and 3 inoculated chickens died on days 3, 4, and 5 postinoculation (PI), respectively. Four, 3, 1, and 1 inoculated chickens became moribund with severe clinical signs such as ruffled feathers, severe depression and closed eyes from days 3 to 6 PI, respectively. Macroscopically, the common characteristic of the gross lesions of dead chickens and euthanized moribund chickens was discoloration of liver. FAV was recovered from the gizzard, liver, pancreas and rectum. Virus titers in the liver and pancreas were high until day 6 PI. Histologically, necrotizing hepatitis and pancreatitis with intranuclear inclusion bodies were observed in the inoculated chickens. These results indicate that some strains of serotype 8 FAV are able to reproduce not only gizzard erosion by oral inoculation but inclusion body hepatitis (IBH) by intramuscular inoculation.

This paper describes the design features and operational status of the RF systems for the KEK B-Factory (KEKB). Two types of new RF cavities have been developed to store very high-intensity beams with many short bunches. The design and performance of the cavities and other critical components, such as the input couplers and HOM dampers, are reported. The configuration of the RF systems is given and descriptions of various control loops are made, including a direct RF feedback loop and a 0-mode damping loop. The effects of transient beam loading due to a bunch gap on bunch phase modulations were simulated and measured. The development of a superconducting crab cavity, which is a component of luminosity upgrade strategy, is also presented.

Twenty 6-week-old specific pathogen-free pigs were divided into four groups. On day 0 of the experiment, PRRSV-PRV (n = 6) and PRRSV (n = 4) groups were intranasally inoculated with porcine reproductive and respiratory syndrome virus (PRRSV) (10(5.6) TCID50). On day 7, the PRRSV-PRV and PRV (n = 6) groups were intranasally inoculated with pseudorabies virus (PRV) (10(3.6) TCID50). Control pigs (n = 4) were kept as uninoculated negative controls. Half of the pigs in each group were euthanized and necropsied on day 14 or 21. Clinical signs such as depression and anorexia were observed in the PRRSV-PRV and PRV groups after inoculation with PRV. Although febrile response was observed after virus inoculations, the duration of that response was prolonged in the PRRSV-PRV group compared with the other groups. The lungs in the PRRSV-PRV group failed to collapse and were mottled or diffusely tan and red, whereas the lungs of the pigs in the other groups were grossly normal. Histopathologically, interstitial pneumonia was present in all PRRSV-inoculated pigs, but the pneumonic lesions were more severe in the PRRSV-PRV group. Mean PRRSV titres of tonsil and lung in the PRRSV-PRV group were significantly (P < 0.05) higher than that in the PRRSV group on day 21. These results indicate that dual infection with PRRSV and PRV increased clinical signs and pneumonic lesions in pigs infected with both viruses, as compared to pigs infected with PRRSV or PRV only, at least in the present experimental conditions.

Recently, coherent control of absorption in metallic metasurfaces has been demonstrated, and this phenomenon was applied to intriguing light-by-light switching operation. Here we experimentally demonstrate coherent control of beam deflection by high-efficiency metasurfaces for the first time. Although the beam deflection efficiency by a metasurface is generally small, high-efficiency metasurfaces, which consist of a single layer metasurface with a back reflector, are known to exhibit significantly high deflection efficiency. A key point of our study is to replace the back reflector with a partial reflector instead, which enables light-by-light control of a high-efficiency metasurface with a pair of counter-propagating coherent beam inputs. By adjusting the partial reflector thickness appropriately, the proposed device outperforms ones without a reflector, especially for the deflection efficiency. We finally experimentally demonstrate the expected operation of the fabricated device at a visible wavelength, which reveals that the deflection efficiency of 45% (49% in theory). This result demonstrates highly efficient light-by-light control of the beam deflection by a metasurface, which opens up possible applications to ultrathin photonic devices for linear all-optical switching and logic functions.

Background Salmonella enterica serovar Enteritidis is a zoonotic pathogen. Human infections are associated with contaminated eggs and egg products. In Japan, since 1989, the incidence of food-borne disease caused by S. Enteritidis has increased and a pandemic has occurred; however, little is known about changes that occurred before and after this pandemic event in the dominant lineage of isolates from food-producing animals. This study aimed to determine the S. Enteritidis lineages in Japan over the last few decades by using multilocus variable-number tandem repeat analysis (MLVA). Findings MLVA was used to analyse 79 S. Enteritidis isolates collected from chickens (n = 63), cattle (n = 12), pigs (n = 2), and goats (n = 2) during 1975–2009. The S. Enteritidis isolates showed 14 different MLVA allele combinations, which were classified into two major clusters (A and C) and a minor cluster (B). All the 62 isolates in cluster A were isolated after 1988, whereas 13 of the 17 isolates belonging to cluster B and C were isolated before 1989. Conclusions The MLVA results showed that cluster C was predominant before 1989, and isolates in cluster A disseminated since 1989 and replaced the previous dominant clone, suggesting that isolates of cluster A originated from imported S. Enteritidis infection.

We have compared the cytology of bronchoalveolar lavage fluid (BALF) and the pathology of lung lesions in pigs immunized with/without Mycoplasma hyopneumoniae inactivated vaccine prepared from broth culture supernate on experimental infection. Numbers of total cells, macrophages, neutrophils and lymphocytes have decreased in BALF of vaccinated pigs following infection. The mean percentage of lung lesions, inflammatory cell infiltration into the airways and T cells accumulation around the bronchi were reduced in vaccinated pigs. The levels of tumor necrosis factor (TNF)-alpha also decreased in vaccinated pigs. These results suggest that the vaccination may contribute to decrease TNF-alpha production, and therefore, inflammatory cell responses in the lung due to M. hyopneumoniae infection were suppressed, resulting in fewer lung lesions.

This paper describes the isolation of porcine epidemic diarrhea (PED) virus in Vero and porcine cell cultures, and the influence of age on disease in experimental infection. PED virus was isolated from the small intestine of piglets inoculated with PED samples and cultured in Vero, porcine bladder and kidney cells propagated in collagen-coated tissue culture plates in maintenance medium (MM) containing trypsin. In porcine bladder and kidney cell cultures inoculated with isolated PED virus, cytopathic effects (CPE) including cell fusion were detected. Specific brilliant fluorescence was observed in the cytoplasm of these cells. Two- and 7-day old, and 2-, 4-, 8- and 12-week old specific pathogen-free (SPF) pigs were orally inoculated with PED virus isolated from an outbreak. All 2- and 7-day old pigs inoculated developed severe watery diarrhea from post-inoculation day (PID) 1 and died between PID 3 and 4. Although three of five 2-week old pigs developed diarrhea on PID 1–4, they eventually recovered. In the 4-week old group, three of five pigs had mild diarrhea for 1–2 days. None of the 8- and 12-week old pigs showed any clinical signs. Antibodies against PED virus were detected in all surviving pigs by virus neutralization (VN) test and immunofluorescence assay (IFA). Therefore, there is an age-dependent resistance to pathogenic PED virus infection in pigs.

The energy trapping characteristic of the thickness longitudinal mode propagating in a 36° rotation Y-cut LiNbO3 single crystal is theoretically analyzed. It is found that the fundamental wave has a high-frequency cutoff characteristic and the third overtone has a low-frequency cutoff characteristic. It is shown that a third-order overtone resonator with a small resonant level of the fundamental wave can be obtained. Further, a simulation analysis of the vibration displacement distribution is performed by the finite element method. The device dimensions for further improvement of the degree of suppression of the fundamental wave are experimentally derived. Based on these investigation results, a 34-MHz resonator was fabricated and a third-overtone resonator with a small fundamental response level with a resonance sharpness of 15,000, a capacitance ratio of 97, and a temperature characteristic of approximately –70 ppm/°C was obtained. The resonator is being mass produced as a clock resonator for a microprocessor operating between 25 and 100 MHz. © 1999 Scripta Technica, Electron Comm Jpn Pt 2, 82(7): 50–58, 1999

For the future large scale application of superconducting (SC) RF cavities like TESLA, one has to fabricate the cavities cheaply to achieve high gradients and high Q values (E/sub acc/>25 MV/m, Q>1/spl times/10/sup 10/). The amount of niobium material has to be decreased and the complex welding structure should be eliminated to reduce the fabrication cost. Here, the authors propose to fabricate seamless clad cavities of niobium and copper material and report the results of a feasibility study.