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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]

This article reports a possible functionalization mechanism of isocyanate (NCO) groups on multiwalled carbon nanotubes (CNTs) with low-temperature plasma. The mechanism was clarified according to the analysis with two plasmas generated with the gas mixture of (1) nitrogen and carbon dioxide and (2) nitrogen and oxygen. We analyzed the mechanism through optical emission spectroscopy from these plasmas and the NCO functionalization ratio measured with the fluorescent method after plasma exposure over CNTs. The optical emission gave us information on the quantitative analysis of the gas species of atomic nitrogen (N), atomic oxygen (O), and carbon monoxide (CO) and the qualitative analysis of carbon nitride (CN) species in the plasma. Compared with our results from the gas species in the plasma and the NCO functionalization ratio on CNTs, CO and CN species in the gas phase in plasma are less likely to contribute to forming NCO groups on CNTs. Rather, the equal densities of atomic nitrogen and oxygen species in the plasma could be effective in forming NCO groups on the CNT surface: the NCO groups should form by N, O, and carbon (C) species on the CNT surface. The groups likely build up gradually by N, O, and C individually reaching a CNT surface, or the NCO radicals form in the gas phase and then attach to the CNT surface. [ABSTRACT FROM AUTHOR]

Shiga toxin (Stx)-producing Escherichia coli (STEC) with the serotype O157:H7 is characterized by the possession of stx gene(s), the locus of enterocyte effacement (LEE)--encoded type 3 secretion system (T3SS), and [...]

Simple Summary: Following the "Replacement/Reduction/Refinement" policy, insects are proposed to replace mammals and birds as experimental models to study the virulence of bacterial pathogens and to identify their virulence properties. The aim of this study was to assess in larvae of the Galleria mellonella moth the virulence of the Shigatoxigenic and enteropathogenic Escherichia coli O80:H2 and the respective roles of two virulence properties: the pS88 plasmid-encoded invasiveness properties and the phage-encoded Shiga toxin 2d. The objectives were to compare: (i) the virulence of bovine Shigatoxigenic and enteropathogenic E. coli O80:H2; (ii) the roles of the pS88 plasmid and Shiga toxin 2d-encoding phage; (iii) the virulence of E. coli O80:H2 and O80:non-H2. The results and the conclusions are: (i) E. coli O80:H2 and O80:non-H2 are lethal at log5 and log6 concentrations; (ii) the pS88 plasmids are partially responsible for the virulence of E. coli O80:H2; (iii) the phage-encoded Stx2d toxin is entirely responsible for the virulence of the Shigatoxigenic Escherichia coli O80:H2; (iv) the virulence properties of E. coli O80:non-H2 could not be identified. As a general conclusion, G. mellonella larvae represent a useful model to study the virulence of bacterial pathogens but are limited in identifying their virulence properties. The invasiveness properties of Shigatoxigenic and enteropathogenic Escherichia coli (STEC and EPEC) O80:H2 in humans and calves are encoded by genes located on a pS88-like ColV conjugative plasmid. The main objectives of this study in larvae of the Galleria mellonella moth were therefore to compare the virulence of eight bovine STEC and EPEC O80:H2, of two E. coli pS88 plasmid transconjugant and STX2d phage transductant K12 DH10B, of four E. coli O80:non-H2, and of the laboratory E. coli K12 DH10B strains. Thirty larvae per strain were inoculated in the last proleg with 10 μL of tenfold dilutions of each bacterial culture corresponding to 10 to 106 colony-forming units (CFUs). The larvae were kept at 37 °C and their mortality rate was followed daily for four days. The main results were that: (i) not only the STEC and EPEC O80:H2, but also different E. coli O80:non-H2 were lethal for the larvae at high concentrations (from 104 to 106 CFU) with some variation according to the strain; (ii) the Stx2d toxin and partially the pS88 plasmid were responsible for the lethality caused by the E. coli O80:H2; (iii) the virulence factors of E. coli O80:non-H2 were not identified. The general conclusions are that, although the Galleria mellonella larvae represent a useful first-line model to study the virulence of bacterial pathogens, they are more limited in identifying their actual virulence properties. [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]

The origin of human and calf infections by Shigatoxigenic (STEC) and enteropathogenic (EPEC) Escherichia coli O80:H2 is still unknown. The aim of this study was to identify E. coli O80 in healthy cattle with an emphasis on melibiose non-fermenting E. coli O80:H2. Faecal materials collected from 149 bulls at 1 slaughterhouse and 194 cows on 9 farms were tested with O80 antigen-encoding gene PCR after overnight growth in enrichment broths. The 53 O80 PCR-positive broths were streaked on different (semi-)selective agar plates. Five E. coli colonies from 3 bulls and 11 from 2 cows tested positive with the O80 PCR, but no melibiose non-fermenting E. coli was isolated. However, these 16 E. coli O80 were negative with PCR targeting the fliCH2, eae, stx1, stx2 and hlyF genes and were identified by WGS to serotypes and sequence types O80:H6/ST8619 and O80:H45/ST4175. They were phylogenetically related to E. coli O80:H6 and O80:H45 isolated from different animal species in different countries, respectively, but neither to STEC and EPEC O80:H2/ST301, nor to other serotypes of the clonal complex 165. As a conclusion, healthy adult cattle were not identified as a source of contamination of humans and calves by STEC or EPEC O80:H2. [ABSTRACT FROM AUTHOR]

We recently reported how effective and important carbon nanotubes with isocyanate groups after plasma treatment are to polyimide composite. This article is the following report showing the monitoring method for the isocyanate functionalization by plasma treatment on carbon nanotubes using optical emissions from nitrogen and oxygen atoms. We measured the functionalization ratio on the nanotubes with the fluorescent measurement and measured the number density in the gas phase with plasma actinometry. The number of the functionalized nanotubes became maximized when the plasma contained almost the same number density of nitrogen atoms as the number density of oxygen atoms in the gas phase. Our plasma utilized in this article reached this condition when the gas mixture of nitrogen and carbon dioxide had 90% of nitrogen content. These overall results indicated that the functionalization during plasma processing can be evaluated with the optical emission from the plasma. [ABSTRACT FROM AUTHOR]

Introduction: Old age is an independent risk factor (RF) for severe COVID-19; evidence for clinico-epidemiological characteristics among elderly COVID-19 patients is scarce. We aimed to analyze clinical and epidemiological characteristics and comorbidities associated with COVID-19 inpatients in age-stratified populations of an elderly COVID-19 cohort. Methods: We conducted a retrospective cohort study, using nationwide registry data of COVID-19 patients hospitalized before October 31, 2020 (major information entered in the registry as of December 28, 2020). Participants were divided by age according to the Japan Geriatrics Society and the Japan Gerontological Society: pre-old (65–74 years), old (75–89 years), and super-old (≥90 years). Multivariable logistic regression (MLR) analyses were conducted to identify stratified risk and relationships with comorbidities associated with worse outcomes in different age-groups of elderly patients. Demographics and supportive care were evaluated by category. Results: Data of 4,701 patients from 444 hospitals were included. Most patients (79.3%) had at least one comorbidity; the proportion of patients with hypertension was high in all categories. The proportion of patients with dementia, cardiovascular disease, and cerebrovascular disease increased with age. The percentage of patients who underwent invasive mechanical ventilation/extracorporeal membrane oxygenation was lower in the super-old group. In total, 11.5% of patients died (5.3%, pre-old; 15.2%, old; and 22.4%, super-old). MLR showed that the risk of critical illness differed among age-groups. Male sex was a significant RF in all ages. Collagen disease, moderate to severe renal disorder, and dialysis were significant RFs in older patients, while hematological malignancies and metastatic tumors were more important RFs for severe disease in relatively younger patients. Most of the RFs for critical illnesses were associated with death. Conclusion: Differences in the epidemiological and clinical characteristics among the different age-groups were found. [ABSTRACT FROM AUTHOR]

To achieve sustainable development goals, meals should promote environmental protection and good health. The excessive salt intake of the Japanese people is one cause of lifestyle diseases. This study evaluated the impact of reducing salt intake on the environment and human health. Over one week, this study compared the lifecycle of a model meal based on a Japanese person's average food intake with a reduced-salt meal, by replacing seasoning/salt with low-salt substitutes. We conducted an inventory assessment of the carbon and water consumption footprints based on the items used in the ingredient and cooking stages. The impact on climate and water consumption was determined using the results of the inventory assessment of the damage factors. We took the global burden of disease result as the health impact of salt intake. The decreased health impact of reduced salt was based on the results of a previous study. The health impact of the ingredient stage of both meals was almost the same. Regarding the assessment of the health impact, the value of the reduced-salt meal was 30% lower than that of the model meal because the salt intake was reduced by 2.8 g per day. We found that the reduced-salt meal could decrease the overall human health impact by 20% because of the reduced incidence of salt-intake-related diseases, despite a small increase in the health impact of reduced-salt seasonings. [ABSTRACT FROM AUTHOR]

In this study, we examined a technique for maximizing the wear resistance of a polyurethane film composited with plasma-treated carbon nanotubes (CNTs). In our previous work, we showed that adding plasma-treated CNTs enhanced the wear resistance of off-the-shelf polyurethane. Here, we also investigated the chemical reactions between polyurethane and plasma-treated CNTs. The result showed that plasma-treatment modified isocyanate groups on CNTs possibly react with polyols to form urethane. However, the off-the-shelf polyurethane was supposed to have limited polyols because urethane reactions were mostly finished. In the present study, we synthesized polyurethane ourselves in order to compare how the timing of synthesis of plasma-treated CNTs into polyurethane (either before or after urethane reactions occur) impacts resulting films. Five polyurethane films were prepared, including a film composited with plasma-treated CNTs synthesized before urethane reactions (in situ polymerized CNT-composite polyurethane film). A wear-resistance test was then conducted to evaluate the mechanical properties of the composite films. The results showed that the plasma-treated CNTs enhanced wear resistance by a factor of two. Next, we conducted a tensile test to examine how the wear resistance was enhanced in polyurethane films composited with plasma-treated CNTs. The tensile test showed that in situ polymerized plasma-treated CNTs significantly improved Young's modulus of CNT-composite polyurethane. These combined results suggested that plasma-treated CNTs should be composited into polyurethane before urethane reactions occur to maximize the wear resistance of composite polyurethane. [ABSTRACT FROM AUTHOR]

The Peltier Current Lead with switching facilities is developed to polarity-reversible superconducting magnet. The results show that the heat leakage could be reduced compared to the conventional current lead when the module is installed with Peltier Current Lead.