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A non-gravid female Onchocercawas found in histopathological sections of a biopsy specimen taken from a painful nodule in the wrist of a 57-year-old woman in Oita, in southern Japan. Six species of Onchocercahave been found in animals in Japan: two in wild bovids, one in equids, and three in domestic bovids of which one, Onchocercasp., is only known by the microfilaria and infective stage. Distinctive morphological features of the worm, including a three-layered thick cuticle with prominent annular ridges at wide intervals, high somatic muscles and narrow lateral chords, resembled those of O. gutturosa, one of the three bovine Onchocercaspecies transmitted in the Oita region. However Onchocercasp., which is also transmitted in this region, cannot be excluded.

Wild female black flies attracted to a man or an idling automobile were collected at Oita, Japan where five cases of zoonotic onchocerciasis had occurred. Among the five Simuliumspecies captured, 2% of Simulium bidentatum, the predominant species, were infected with filarial larvae. There were at least two types of infective larvae, types A and B, based on morphometric observation. Moreover, molecular analysis of the mitochondrial cytochrome coxidase subunit 1 (CO1) gene revealed that types A and B were represented by a single unknown species of Onchocercaand two species, i.e., Onchocerca dewittei japonicafrom wild boar, the causative agent of zoonotic onchocerciasis in Japan, and an undescribed Onchocercasp. from wild boar, respectively. Phylogenetic analysis based on the sequences of the mitochondrial 12S ribosomal RNA (12S rRNA) gene also showed that type A is likely to be an unknown species of Onchocerca. Natural infection of black flies with infective larvae of O. dewittei japonicaand O.sp. was demonstrated for the first time. The present study strongly suggests that S. bidentatumplays a role as a vector in the transmission of zoonotic onchocerciasis due to O. dewittei japonicain Japan.

In order to clarify the genetic differences between Onchocerca dewittei japonica, the causative agent of zoonotic onchocerciasis in Japan and a related undescribed Onchocercasp., both parasitizing wild boar (Sus scrofa) of which the infective larval stages are indistinguishable from each other, we compared the sequences of the mitochondrial cytochrome coxidase subunit 1 (CO1) gene region from four infective larvae (recovered from experimentally infected black flies), one microfilaria, and one adult of O. dewittei japonica, and from one infective larva (recovered from an experimentally infected black fly), one microfilaria, and a pool of several microfilariae of O. sp. The length of the CO1 gene region was 649 bp for all samples but there was a difference of 8.8 to 9.4% in the sequences between the two species although there were intraspecific variations of 0 to 0.5%. The CO1 sequences of O. sp. did not correspond to any of those deposited in the databases. Our study provides evidence that O. dewittei japonicaand O. sp. are genetically different from each other.

Microfilariae of five Onchocercaspecies, O. dewittei japonica(the causative agent of zoonotic onchocerciasis in Oita, Kyushu, Japan) from wild boar (Sus scrofa), O. skrjabiniand O. eberhardifrom sika deer (Cervus nippon), O. lienalisfrom cattle, and an as yet unnamed Onchocercasp. from wild boar, were injected intrathoracically into newly-emerged black flies of several species from Oita to search the potential vector(s) of these parasites and identify their infective larvae. Development of O. dewittei japonicamicrofilariae to the infective larvae occurred in Simulium aokii, S. arakawae, S. bidentatum, S. japonicum, S. quinquestriatum, and S. rufibasiswhile development of infective larvae of O. skrjabini, O. eberhardi, and the unnamed Onchocercasp. was observed in S. aokii, S. arakawae, and S. bidentatum. Development of O. lienalismicrofilaria to infective larvae occurred in S. arakawae. Based on the morphology of infective larvae obtained, we proposed a key of identification of Onchocercainfective larvae found in Oita. We also reconsider the identification of three types of infective larvae previously recovered from Simuliumspecies captured at cattle sheds: the large type I larvae that may be an undescribed species; the small type III identified as O. lienalismay include O. skrjabinitoo; the intermediary type II that may be O. gutturosa, or O. dewittei japonica, or the unnamed Onchocercasp. of wild boar.

Seasonal and daily biting activity patterns, and natural filarial infections of adult black flies attracted to human bait were investigated at Ban Pang Faen, a rural area in Chiang Mai Province in northern Thailand. Collections were carried out twice a month from 06-00 to 18-00 hours from January 2005 to February 2006. Among ten Simuliumspecies collected, S. nodosumand S. asakoaewere predominant occupying 57.3% and 37.2% of the total 16, 553 females, respectively. These two predominant species showed different patterns in seasonal abundance: majority of S. nodosum(86.7%) were collected in hot season (from mid February to mid May), while most of S. asakoae(74.5%) were collected in rainy season (from mid May to mid October). For the daily biting activity, S. nodosumhad two patterns: the main one was unimodal with a peak from 17-00 to 18-00, and the other was bimodal and had the major peak from 16-00 to 18-00 and the minor one from 07-00 to 09-00. The pattern of S. asakoaewas mostly unimodal with a peak from 06-00 to 10-00. The filarial larvae found in S. nodosumand S. asakoaewere morphologically different from each other. The short and thick infective larvae found in S. asakoaediffered from all known filarial larvae; it is suggested that they might be a bird parasite, Splendidofilariinae or Lemdaninae. The infection of the mammophilic S. nodosumwith large Onchocercatype infective larvae was confirmed in this area. Natural filarial infections were found in each month (except December) in either S. nodosumor S. asakoaeor in both. Monthly infection rates with all stages of larvae were 0.6-5.0% for S. nodosum,and 1.0-4.0% for S. asakoae.It is suggested that people in this village are exposed to the risk of infection with zoonotic filariae throughout the year.

The initial value problems for the Korteweg-de Vries (KdV) and modified KdV (mKdV) equations under periodic and decaying boundary conditions are considered. These initial value problems are shown to be globally well-posed in all $L^2$-based Sobolev spaces $H^s$ where local well-posedness is presently known, apart from the $H^{\frac{1}{4}} (R )$ endpoint for mKdV and the $H^{-\frac{3}{4}}$ endpoint for KdV. The result for KdV relies on a new method for constructing almost conserved quantities using multilinear harmonic analysis and the available local-in-time theory. Miura's transformation is used to show that global well-posedness of modified KdV is implied by global well-posedness of the standard KdV equation.

Chlamydiae proliferate only within the infected host cells and are thought to be "energy parasites," because they take up ATP from the host cell as an energy source. In the present study, we isolated from Chlamydia pneumoniae the gene encoding adenylate kinase (AK). Using the enzyme produced in Escherichia coli, its properties were characterized. K(m) values for AMP and for ADP of the purified C. pneumoniae AK (AKcpn) were each 330 microm, which is significantly higher than the reported values of other AKs, whereas K(m) for ATP was 24 microm, which was rather lower than others. AKcpn contains 1 g atom of zinc/mol of 24,000-dalton protein. Mass spectrometric analysis of AKcpn and analysis of properties of mutated AKcpn strongly suggested that zinc is associated with four cysteine residues in the LID domain of the enzyme. The apo-AKcpn that lost zinc retained AK activity, although K(m) for AMP of apo-AKcpn increased about 2-fold and V(max) decreased about one-half from that of holo-AKcpn. The apo-AKcpn was more thermolabile and sensitive to trypsin digestion than the holo-AKcpn. Moreover, the recovery in vitro of the AK activity during the renaturation process of the denatured apo-AKcpn was dependent on zinc. A mutated protein in which cysteine residues in the LID domain were substituted by other amino acids lost both zinc and enzyme activity. The mutated protein was more sensitive to protease than the apo-AKcpn. These results indicate that zinc in AKcpn, although not essential for the catalysis, stabilizes the enzyme and probably plays a crucial role in proper folding of the protein. Furthermore, the catalytic properties of AKcpn suggest a distinctive regulatory mechanism in the metabolism compared with AKs in other organisms.

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Recently, many people have realized that digital training simulators are very useful and economical for power plant operation training. They have been rapidly improved with the progress of computer technology, since the first digital simulator was installed more than ten years ago.

Although conventional inotropic agents such as catecholamines increase myocardial oxygen consumption, a newly developed inotropic agent, a Ca ^2^+ sensitizer, may be able to increase cardiac output with less myocardial oxygen consumption. By using right-side heart catheterization, we assessed the ratio of the increase in myocardial oxygen consumption per unit increase in cardiac output during @b-adrenergic receptor stimulation (dobutamine, n = 15), phosphodiesterase inhibition (E-1020, n = 10), and Ca ^2^+ sensitization (MCI-154, n = 17) in patients with coronary artery disease. Dobutamine increased cardiac output and myocardial oxygen consumption. E-1020 increased cardiac output but did not change myocardial oxygen consumption. MCI-154 increased cardiac output and decreased myocardial oxygen consumption. The oxygen cost of increasing cardiac output with dobutamine and with E-1020 was different from that with dextran infusion ( n = 18); in contrast, the oxygen cost with MCI-154 was significantly smaller. Thus a newly developed Ca ^2^+ sensitizer, MCI-154, may be beneficial for the treatment of heart failure. (Am Heart J 1997;133:283-9.)

Based on the recent trends of the international energy policy, the most significant purpose of newly built power generating plants is to reduce the fuel cost as much as possible. Gas/steam combined cycle power generation has been adopted in order to realize this important purpose. The major design philosophy of this control is to harmonize the central control room equipment for one-man operation and the control equipment for each component.

One simple form of combined cycle system consists of a gas turbine, a heat recovery steam generator, a steam turbine and a generator. One set ot these combined cycle cumpuneiits may be called a “stage”. By combining several Stages, a large capacity power plant can be realized with the following features; (1) high efficiency (2) high efficiency at partial load and (3) rapid start-up and shut-down.

In practical applications to large-scale power plant control systems, more and more digital controllers, computers and communication links are being used in recent years. A control system of a gas/steam combined cycle power plant is described as a typical example of such control systems and it is discussed how they are used and how hard–wired control systems are still used as current practice.