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This article reports the quantitative effect on carbon nanotubes (CNTs), which are exposed to low‐temperature plasma, for the purpose of a filler application of polyurethane (PU) composite. The plasma exposure provides an opportunity for the surface modification of the CNTs, so the exposure possibly enhances the interfacial interaction in PU composite. In this article, we carried out a wear‐resistant examination to investigate the mechanical property of the PU composite with plasma‐treated CNTs with a variation of the CNT concentration in the PU composite. Our results showed that plasma treatment assisted the resistance of the PU composite. Furthermore, our observation showed that plasma treatment gives a good dispersion in the composite and possibly enhances interfacial interaction due to surface modification. [ABSTRACT FROM AUTHOR]

Many Rickettsia species of the spotted fever group (SFG) cause tick‐borne diseases known as "spotted fever." One of the candidate SFG Rickettsia species is "Candidatus Rickettsia kotlanii," which was first detected in Haemaphysalis concinna in Hungary in 2006. However, its precise phylogenetic position in the SFG is not clear because only single‐gene sequence–based phylogenetic analyses were performed using very limited genes. Here, we present the complete genome sequences of two Japanese "Ca. R. kotlanii" isolates, which differed only by a 135 bp insertion/deletion (InDel). Using these genomes and publicly available whole genome sequences of other Rickettsia species, the precise phylogenetic position of "Ca. R. kotlanii" in Rickettsia was determined to be in a clade of the SFG. The phylogenetic relationships and average nucleotide identity of "Ca. R. kotlanii" relative to the other species indicated that "Ca. R. kotlanii" is an independent taxon in the SFG. Notably, although the genomes of the two isolates were almost identical, the isolates were obtained from different tick species in different regions and years, suggesting extremely low genomic diversity in "Ca. R. kotlanii." While the genome of "Ca. R. kotlanii" is the smallest in the transitional group and SFG Rickettsia sequenced to date, we identified genes uniquely present or absent in "Ca. R. kotlanii," but most were apparently degraded. Therefore, analyses of differences at the sequence (single nucleotide polymorphisms and small InDels) or gene expression level will be required to understand the functional or physiological features unique to "Ca. R. kotlanii." [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and safety of direct hemoperfusion using a polymyxin B‐immobilized polystyrene column (PMX‐DHP) in severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)‐positive pneumonia patients. Methods: This study was a case series conducted at a designated infectious diseases hospital. Twelve SARS‐CoV‐2‐positive patients with partial pressure of arterial oxygen/percentage of inspired oxygen (P/F) ratio < 300 were treated with PMX‐DHP on two consecutive days each during hospitalization. We defined day 1 as the first day when PMX‐DHP was performed. PMX‐DHP efficacy was assessed on days 7 and 14 after the first treatment based on eight categories. Subsequently, improvement in P/F ratio and urinary biomarkers on days 4 and 8, malfunctions, and ventilator and extracorporeal membrane oxygenation avoidance rates were also evaluated. Results: On day 14 after the first treatment, disease severity decreased in 58.3% of the patients. P/F ratio increased while urine β2‐microglobulin decreased on days 4 and 8. Cytokine measurement pre‐ and post‐PMX‐DHP revealed decreased levels of interleukin‐6 and the factors involved in vascular endothelial injury, including vascular endothelial growth factor. Twenty‐two PMX‐DHPs were performed, of which seven and five PMX‐DHPs led to increased inlet pressure and membrane coagulation, respectively. When the membranes coagulated, the circuitry needed to be reconfigured. Circuit problems were usually observed when D‐dimer and fibrin degradation product levels were high before PMX‐DHP. Conclusions: Future studies are expected to determine the therapeutic effect of PMX‐DHP on COVID‐19. Because of the relatively high risk of circuit coagulation, coagulation capacity should be assessed beforehand. [ABSTRACT FROM AUTHOR]

We report a case of a 64‐year‐old woman with a past medical history (PMH) of prosthetic valve replacement 7 months prior to admission, who presented with only right back pain. Physical examination revealed one conjunctival spot hemorrhage and a mild systolic murmur. Blood cultures were positive for methicillin‐resistant Staphylococcus epidermidis. Trans‐esophageal echocardiography revealed aortic valve vegetations; hence, a diagnosis of prosthetic valve endocarditis (PVE) was made. Clinical presentation of infective endocarditis varies and sometimes mimics that of polymyalgia rheumatica. The patient was diagnosed as PVE considering the whole clinical picture including the patient's PMH, physical examination, and blood cultures. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) is ongoing and spreading worldwide after cases of COVID-19 were reported in Wuhan, China in December 2019.1 Older age, diabetes, hypertension, and smoking have been reported as aggravating factors,2 and human immunodeficiency virus (HIV) infection is considered to be a potentially aggravating factor. There are very few reports of COVID-19 in untreated HIV patients3-5 HIV patients are known to be susceptible to respiratory viruses and to have more severe symptoms, but the clinical course and prognosis of COVID-19 in HIV patients are not known yet. COVID-19 pneumonia in untreated HIV patients requires careful follow-up for IRIS with ART. [Extracted from the article]

ABSTRACT Clostridium botulinum produces the highly potent neurotoxin, botulinum neurotoxin (BoNT), which is classified into seven serotypes (A-G); the subtype classification is confirmed by the diversity of amino acid sequences among the serotypes. BoNT from the Osaka05 strain is associated with type B infant botulism and has been classified as BoNT/B subtype B6 (BoNT/B6) by phylogenetic analysis and the antigenicity of its C-terminal heavy chain (HC) domain. However, the molecular bases for its properties, including its potency, are poorly understood. In this study, BoNT/B6 holotoxin was purified and the biological activity and receptor binding activity of BoNT/B6 compared with those of the previously-characterized BoNT/B1 and BoNT/B2 subtypes. The derivative BoNT/B6 was found to be already nicked and in an activated form, indicating that endogenous protease production may be higher in this strain than in the other two strains. BoNT/B1 exhibited the greatest lethal activity in mice, followed by BoNT/B6, which is consistent with the sensitivity of PC12 cells. No significant differences were seen in the enzymatic activities of the BoNT/Bs against their substrate. HC/B1 and HC/B6 exhibited similar binding affinities to synaptotagmin II (SytII), which is a specific protein receptor for BoNT/B. Binding to the SytII/ganglioside complex is functionally related to the toxic action; however, the receptor recognition sites are conserved. These results suggest that the distinct characteristics and differences in biological sensitivity of BoNT/B6 may be attributable to the function of its Hc.domain. [ABSTRACT FROM AUTHOR]

ABSTRACT Bordetella pertussis causes whooping cough, a severe and prolonged respiratory disease that results inhas high morbidity and mortality rates, particularly in developing countries. The number incidence of whooping cough cases is increasing in many countries despite high vaccine coverage. Causes for the re-emergence of the disease include the limited duration of protection conferred by the acellular pertussis vaccines (aP)s and pathogenic adaptations that involve antigenic divergence from vaccine strains. Therefore, current vaccines therefore need to be improved. In the present study, we focused on five autotransporters: namely SphB1, BatB, SphB2, Phg, and Vag8, which were previously found to be expressed by B. bronchiseptica during the course of infection in rats and examined their protective efficiencies as vaccine antigens. The passenger domains of these proteins were produced in recombinant forms and used as antigens. An intranasal murine challenge assay showed that immunization with a mixture of SphB1 and Vag8 (SV) significantly reduced bacterial load in the lower respiratory tract and a combination of aP and SV acts synergistically in effects of conferring protection against B. pertussis infection, implying that these antigens have potential as components to for improvinge th the currently available acellular pertussis vaccine. [ABSTRACT FROM AUTHOR]

ABSTRACT Bordetella species display phase modulation between Bvg+ and Bvg− phases. Because expression of known virulence factors is up-regulated in the Bvg+ phase, bacteria in this phase are considered competent for infection. However, the Bvg− phase is of negligible importance for infection. No studies have shown that bacterial factors specific to the Bvg− phase ( bvg-repressed factors) are expressed in the course of Bordetella infection. In the present study, the gene brtA ( Bordetella RTX-family Adhesin), which is a typical bvg-repressed gene but is expressed in B. bronchiseptica infecting hosts, was characterized. BrtA is composed of repeated pairs of the VCBS unit and dystroglycan-type cadherin-like unit, the von Willebrand Factor A domain, RTX motif and type I secretion target signal. It is herein demonstrated that BrtA is secreted by the type I secretion system and is essential for Ca2+-dependent bacteria-to-substrate adherence, followed by biofilm formation. Although the contribution of BrtA to bacterial colonization of the rat trachea currently remains unclear, this is the first study to present concrete evidence for the expression of a bvg-repressed gene during infection, which may provide a novel aspect for analyses of Bordetella pathogenesis. [ABSTRACT FROM AUTHOR]

ABSTRACT Analyses of bacterial genes expressed in response to the host environment provide clues to understanding the host-pathogen interactions that lead to the establishment of infection. In this study, a novel method named In Vivo Expressed-Tag ImmunoPrecipitation (IVET-PI) was developed for detecting genes expressed in bacteria that are recovered in a small numbers from host tissues. IVET-IP was designed to overcome some drawbacks of previous similar methods. We applied IVET-IP to Bordetella bronchiseptica colonizing rat trachea and identified 173 genes that were expressed in the bacteria over the entire course of an infection. These gene products included two transcriptional factors that are involved in the expression of filamentous hemagglutinin, adenylate cyclase toxin, and major virulence factors for the bordetellae. We consider that this method might provide novel insight into the course of Bordetella infection. [ABSTRACT FROM AUTHOR]

ABSTRACT Botulinum neurotoxins (BoNTs) inhibit neurotransmitter release at peripheral nerve terminals. They are serologically classified from A to G, C/D and D/C mosaic neurotoxins forming further subtypes of serotypes C and D. Cultured primary neurons, as well as neuronal cell lines such as PC12 and Neuro-2a, are often utilized in cell-based experiments on the toxic action of botulinum toxins. However, there are very few reports of the use of neural cell lines for studying BoNTs/C and D. In addition, the differentiated P19 neuronal cell line, which possesses cholinergic properties, has yet to be tested for its susceptibility to BoNTs. Here, the responsiveness of differentiated P19 cells to BoNT/C and BoNT/DC is reported. Both BoNT/C and BoNT/DC were shown to effectively bind to, and be internalized by, neurons derived from P19 cells. Subsequently, the intracellular substrates for BoNT/C and BoNT/DC were cleaved by treatment of the cells with the toxins in a ganglioside-dependent manner. Moreover, P19 neurons exhibited high sensitivity to BoNT/C and BoNT/DC, to the same extent as cultured primary neurons. These findings suggest that differentiated P19 cells possess full sensitivity to BoNT/C and BoNT/DC, thus making them a novel susceptible cell line for research into BoNTs. [ABSTRACT FROM AUTHOR]

This paper describes in-process measurements of secondary electron emission coefficient (SEEC) during plasma immersion ion implantation for a plane target. In the plane target, trajectories of secondary electrons (SEs) emitted from the target strongly depend on the plasma conditions as well as the amplitude of pulse voltages applied to the target because of variation of the curvature radius of the sheath formed around the target. Therefore, absolute measurements of the SE current as well as of the SEEC were difficult to perform. However, calibration of an SE detector using a plane target with very high SEEC enabled the SEEC measurements. The measurements of the SE current revealed that the sheath curvature was affected by the plasma condition and the target shape. This calibration will be useful for SEEC measurements of arbitrary-shaped target. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(3): 1–7, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20096 [ABSTRACT FROM AUTHOR]

Abstract The effect of photoperiod on nymphal development, growth and adult size was examined in a pentatomid bug, Dolycoris baccarum , collected in Osaka (a warm temperate region) and Hokkaido (a subfrigid region), Japan. When insects were reared from eggs at 25°C, the developmental period was long and adult size was large under photoperiods close to the critical photoperiod for the induction of adult diapause. Adults of the Hokkaido population were larger than those of the Osaka population. There was no significant correlation between developmental period and adult size. Insects also showed variation in their growth rate: growth rate was low under photoperiods a little longer than the critical photoperiod for the induction of diapause. The ecological significance of variation in development and growth is discussed. [ABSTRACT FROM AUTHOR]

Abstract. Effects of temperature and photoperiod on the induction and re-induction of adult diapause were examined in Dybowskyia reticulata (Dallas) (Heteroptera: Pentatomidae). Adults collected from the field after overwintering in early summer continued oviposition under long-day conditions of LD 16:8 h at 20 or 25°C, while they re-entered diapause under short-day conditions of LD 12:12 h at 25, 27.5 or 30°C. By contrast, adults reared in the laboratory from eggs at 20 or 25°C entered diapause under both long-day and short-day conditions, whereas those reared at 27.5 and 30°C entered diapause only under short-day conditions. Under quasi-natural conditions in 1993, when summer temperature was low, most adults of the first generation entered diapause in late July. However, in the warmer summer of 1996, oviposition was recorded in many females that ecdysed into adults from July to early August. Even though the seeds of the host plants occur in a restricted period from early summer to early autumn, in warmer years D. reticulata may produce a second generation. The response to temperature with a threshold between 25 and 27.5°C in D. reticulata brings about a switch between the univoltine and bivoltine life cycles. [ABSTRACT FROM AUTHOR]

This study is carried out to examine the possibility of lightning control using a photoionized plasma produced by a UV laser without an optical air breakdown. As the fundamental experiment, the characteristics of a laser-triggered spark gap (LTSG) are examined, where a laser beam is not irradiated on the surface of the electrodes. In this experiment, the KrF excimer laser is very effective in increasing the plasma density ne and the reduction ratiop of 50 percent breakdown voltage against the self-breakdown voltage. The relation between ne and p is increased by generating a long and high-density plasma parallel to the discharge axis. On the other hand, the abnormal discharge process in triggered lightning using a rocket is examined, and it is indicated that the most important condition to trigger a lightning discharge is the production of a plasma channel of length 200 m and density about 1019 m-3. It is suggested that such a plasma channel could be produced by a KrF excimer laser with an energy of only about 3.67 J. [ABSTRACT FROM AUTHOR]

Focuses on remote inspection of cracked electric insulator. Nondestructive inspection of material; Laser beam in inspections.

The operation of many thin-film ETDL's covering a wide wavelength range from near UV to near infrared has been reported. However, the spectral narrowing and tuning of these solid dye lasers are required inevitably for several applications. Therefore, to obtain this operation, the oscillator with a dynamic distributed feedback (DFB) and the optical amplifier were constructed simply on the thin-film ETDL waveguide. As a result, the tunable laser emission with narrow spectrum and its amplification were obtained easily over both gain bands of donor and acceptor dye. Thus, this system is available as a compact solid dye laser with wide tuning range. [ABSTRACT FROM AUTHOR]

Botulinum toxin (BoNT) from Clostridium botulinum OFD05, isolated from bovine botulism, is a D/C mosaic-type BoNT. BoNTs possess binding, translocation and catalytic domains. The BoNT/OFD05 binding domain exhibits significant sequence identity to BoNT/C, which requires a single ganglioside as a binding receptor on neuronal cells, while BoNT/A and BoNT/B require two receptors for specific binding. To determine the binding mechanism of BoNT/OFD05 and its ganglioside receptors on neuronal cells, recombinant BoNT/OFD05 receptor-binding domain has been expressed, purified and crystallized. Native and SeMet-derivative crystals showed X-ray diffraction to 2.8 and 3.1 Å resolution, respectively. The crystals belonged to space group P212121. [ABSTRACT FROM AUTHOR]