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In this study, we describe the genetic characteristics of influenza A(H1N1)pdm09 strains detected in Myanmar from 2015 to 2019. Whole genomes from 60 A(H1N1)pdm09 virus isolates were amplified using real-time polymerase chain reaction and successfully sequenced using the Illumina iSeq100 platforms. Eight individual phylogenetic trees were retrieved for each segment along with those of the World Health Organization (WHO)-recommended Southern Hemisphere vaccine strains for the respective years. A(H1N1)pdm09 viruses from 2015 were found to belong to clade 6B, those from 2016 to 6B.1, 2017 to 6B.1A, and 2019 to 6B.1A.5a, and were genetically distinct from the Southern Hemisphere vaccine strains for the respective seasons, A/California/7/2009 and A/Michigan/45/2015. We observed one virus with intra-subtype reassortment, collected in the 2015 season. Importantly, three viruses possessed the H275Y substitution in the neuraminidase protein, appearing to be community-acquired without the prior administration of neuraminidase inhibitors. These viruses exhibited highly reduced susceptibility to oseltamivir and peramivir. This study demonstrates the importance of monitoring genetic variations in influenza viruses that will contribute to the selection of global influenza vaccines. [ABSTRACT FROM AUTHOR]

Ixodid ticks, such as Ixodes ovatus and Haemaphysalis flava, are important vectors of tick-borne diseases in Japan, such as Japanese spotted fever caused by Rickettsia japonica. This study describes the Rickettsia infection rates influenced by the population genetic structure of I.ovatus and H. flava along an altitudinal gradient. A total of 346 adult I. ovatus and 243 H. flava were analyzed for the presence of Rickettsia by nested PCR targeting the 17kDA, gltA, rOmpA, and rOmpB genes. The population genetic structure was analyzed utilizing the mitochondrial cytochrome oxidase 1 (cox1) marker. The Rickettsia infection rates were 13.26% in I. ovatus and 6.17% in H. flava. For I. ovatus, the global FST value revealed significant genetic differentiation among the different populations, whereas H. flava showed non-significant genetic differentiation. The cox1 I. ovatus cluster dendrogram showed two cluster groups, while the haplotype network and phylogenetic tree showed three genetic groups. A significant difference was observed in Rickettsia infection rates and mean altitude per group between the two cluster groups and the three genetic groups identified within I. ovatus. No significant differences were found in the mean altitude or Rickettsia infection rates of H. flava. Our results suggest a potential correlation between the low gene flow in I. ovatus populations and the spatially heterogeneous Rickettsia infection rates observed along the altitudinal gradient. This information can be used in understanding the relationship between the tick vector, its pathogen, and environmental factors, such as altitude, and for the control of tick-borne diseases in Japan. [ABSTRACT FROM AUTHOR]

Data are limited on the incidence of coronavirus disease 2019 (COVID-19) reinfection in children. This population-based cohort study in Niigata, Japan from January to November 2022 demonstrated the incidence of reinfection was 1337/48 099 (2.8%), and the hazard ratio for reinfection in vaccinated children was 0.29 (95% confidence interval, 0.20–0.40). [ABSTRACT FROM AUTHOR]

Ethanolamine plasmalogens (EPls) are the only known ligands of a novel receptor, G protein‐coupled receptor 61, and bovine brain EPls stimulate follicle‐stimulating hormone (FSH) but not luteinizing hormone (LH), secreted by bovine gonadotrophs. We hypothesized that the brain EPls of whales (Balaenoptera edeni), another Cetartiodactyla with at least twice the lifespan of bovines, could stimulate FSH secretion by gonadotrophs. To test this hypothesis, bovine gonadotrophs (from approximately 2‐year‐old Japanese Black heifers) were cultured for 3.5 days and treated with increasing concentrations of brain EP1s from whales (approximately 22 years old). FSH and LH secretion was stimulated by all tested concentrations of whale EPls (p < 0.05). To clarify the important differences between bovine and whale EPls, we utilized two‐dimensional liquid chromatography–mass spectrometry, which revealed 35 peaks. Among them, we observed significant differences between 12 EPl molecular species. Additionally, we identified differentially expressed genes for enzymes involved in EPl synthesis or degradation in the hypothalamus of young heifers and old cows (approximately 10 years old) as compared to whales (approximately 28 years old) via deep sequencing of the transcriptome. We conclude that whale brains contain unique EPls that stimulate both FSH and LH secretion by bovine gonadotrophs. [ABSTRACT FROM AUTHOR]

The sandeel species (Ammodytes spp.) occupy a critical ecological position in connecting lower trophic levels to higher ones. However, they are strongly affected by the marine environment and their catch rates are trending downward. In this study, the target strength (TS) of sandeel species was measured in free-swimming specimens using a split-beam quantitative echo sounder with 38 and 120 kHz frequencies in a physically controlled environment. Parameters a and b used in the estimated TSmean–fork length (FL: 13.5–21.5 cm) equation were 53.7 and −124.3 dB at 38 kHz, and 71.3 and −153.2 dB at 120 kHz, respectively. The TS of the sandeel species were not proportional to the square of the FL but increased relatively rapidly with increasing body size. In addition, the mean and standard deviation of the swimming angle for the sandeel species from the acoustic data at 120 kHz were −2.2° and 7.7°, respectively, and most were in the −30° to 30°, range. Furthermore, TS was stronger at 38 kHz than at 120 kHz for all FL classes. The use of such frequency characteristics could facilitate the discrimination of fish species in the field and the sustainable assessment of sandeel species stocks. [ABSTRACT FROM AUTHOR]

Objective: This study examined the knowledge, attitudes, and practices (KAP) of an at-risk population living in Niigata prefecture regarding tick-borne diseases (TBDs) and preventive strategies. Methods: A cross-sectional questionnaire-based study was conducted to assess the KAP of the community. Results: In total, 186 responses were received. Among the respondents, 130 (69·9%) were men, and the mean age was 51.1 (14·3). Nine (4·8%) respondents reported having experienced tick bites. Of the respondents, 44 (23.7%) knew about both scrub typhus and severe fever with thrombocytopenia syndrome, while 156 (83·9%) and 71 (38·2%) recognized limiting skin exposure and use of insect repellents as preventive measures, respectively. The attitudes towards TBDs: being worried about tick bites (p = 0·018) and interested in preventing TBDs (p = 0·001), were significantly higher among women than men. About 75% of the respondents reported taking preventive measures against tick bites, and limiting skin exposure was the most frequently applied method (69·9%). Insect repellents were used by 58 (31·2%) respondents. Age (p = 0·049), being worried about tick bites (p = 0·046), and knowledge of ticks score (p = 0·024) were the significant independent predictors of practicing countermeasures. Conclusion: We identified gaps in knowledge and practices regarding TBDs. Public health interventions should be implemented to improve public awareness of TBDs. [ABSTRACT FROM AUTHOR]

The taxonomy of the genus Pennella Oken, 1815 , a large parasitic copepod, is in a deplorable state. We performed morphological and genetic analyses on 52 Pennella individuals collected from 12 species of definitive hosts. Based on the morphological characteristics and their hosts, 29 individuals were determined or suggested to be large-size species (P. balaenoptera , P. filosa , P. instructa , and P. benz i), whereas 20 were considered intermediate- or small-size species. The remaining three small individuals, presumed to be newly attached, exhibited insufficient morphological characteristics for species identification or grouping. Mitochondrial DNA cytochrome c oxidase subunit 1 (COI) sequence analysis detected 154 haplotypes from 52 individuals classified into Groups I–IV. Sequences of Group IV were determined to be pseudogenes. Levels of divergence between all groups were significant (F ST = 0.488–0.830, P < 0.001). All haplotypes of Group I were detected in intermediate- and small-size groups possessing large and well-branched antennary processes on the cephalothorax. Although Groups I and II exhibited the smallest difference in nucleotide sequence divergence (F ST = 0.488 and K2P = 1.485 ± 0.355%), the morphological characteristics of Group I appeared to be distinct from those of the other groups. The substantial sequence divergence (F ST = 0.830 and K2P = 4.123 ± 0.719%) between Groups II and III also supported their species status, but no characteristic morphological difference was observed between individuals in these groups. Results suggest that Pennella may contain only two or three species. and that some morphological characteristics and definitive host species previously used for species identification are not valid. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID-19) has caused a serious disease burden and poses a tremendous public health challenge worldwide. Here, we report a comprehensive epidemiological and genomic analysis of SARS-CoV-2 from 63 patients in Niigata City, a medium-sized Japanese city, during the early phase of the pandemic, between February and May 2020. Among the 63 patients, 32 (51%) were female, with a mean (±standard deviation) age of 47.9 ± 22.3 years. Fever (65%, 41/63), malaise (51%, 32/63), and cough (35%, 22/63) were the most common clinical symptoms. The median C t value after the onset of symptoms lowered within 9 days at 20.9 cycles (interquartile range, 17–26 cycles), but after 10 days, the median C t value exceeded 30 cycles (p < 0.001). Of the 63 cases, 27 were distributed in the first epidemic wave and 33 in the second, and between the two waves, three cases from abroad were identified. The first wave was epidemiologically characterized by a single cluster related to indoor sports activity spread in closed settings, which included mixing indoors with families, relatives, and colleagues. The second wave showed more epidemiologically diversified events, with most index cases not related to each other. Almost all secondary cases were infected by droplets or aerosols from closed indoor settings, but at least two cases in the first wave were suspected to be contact infections. Results of the genomic analysis identified two possible clusters in Niigata City, the first of which was attributed to clade S (19B by Nexstrain clade) with a monophyletic group derived from the Wuhan prototype strain but that of the second wave was polyphyletic suggesting multiple introductions, and the clade was changed to GR (20B), which mainly spread in Europe in early 2020. These findings depict characteristics of SARS-CoV-2 transmission in the early stages in local community settings during February to May 2020 in Japan, and this integrated approach of epidemiological and genomic analysis may provide valuable information for public health policy decision-making for successful containment of chains of infection. [ABSTRACT FROM AUTHOR]

A community outbreak of human influenza A(H1N1)pdm09 virus strains was observed in Myanmar in 2017. We investigated the circulation patterns, antigenicity, and drug resistance of 2017 influenza A(H1N1)pdm09 viruses from Myanmar and characterized the full genome of influenza virus strains in Myanmar from in-patients and out-patients to assess the pathogenicity of the viruses. Nasopharyngeal swabs were collected from out-patients and in-patients with acute respiratory tract infections in Yangon and Pyinmana City in Myanmar during January-December 2017. A total of 215 out-patients and 18 in-patients infected with A(H1N1)pdm09 were detected by virus isolation and real-time RT-PCR. Among the positive patients, 90.6% were less than 14 years old. Hemagglutination inhibition (HI) antibody titers against A(H1N1)pdm09 viruses in Myanmar were similar to the recommended Japanese influenza vaccine strain for 2017–2018 seasons (A/Singapore/GP1908/2015) and WHO recommended 2017 southern hemisphere vaccine component (A/Michigan/45/2015). Phylogenetic analysis of the hemagglutinin sequence showed that the Myanmar strains belonged to the genetic subclade 6B.1, possessing mutations of S162N and S164T at potential antigenic sites. However, the amino acid mutation at position 222, which may enhance the severity of disease and mortality, was not found. One case with no prior history of oseltamivir treatment possessed H275Y mutated virus in neuraminidase (NA), which confers resistance to oseltamivir and peramivir with elevated IC50 values. The full genome sequence of Myanmar strains showed no difference between samples from in-patients and out-patients, suggesting no additional viral mutations associated with patient severity. Several amino acid changes were observed in PB2, PB1, and M2 of Myanmar strains when compared to the vaccine strain and other Asian strains. However, no mutations associated with pathogenicity were found in the Myanmar strains, suggesting that viral factors cannot explain the underlying reasons of the massive outbreak in Myanmar. This study reported the first detection of an oseltamivir-resistant influenza virus in Myanmar, highlighting the importance of continuous antiviral monitoring and genetic characterization of the influenza virus in Myanmar. [ABSTRACT FROM AUTHOR]

We investigated the circulation patterns of human influenza A and B viruses in Myanmar between 2010 and 2015 by analyzing full HA genes. Upper respiratory tract specimens were collected from patients with symptoms of influenza-like illness. A total of 2,860 respiratory samples were screened by influenza rapid diagnostic test, of which 1,577 (55.1%) and 810 (28.3%) were positive for influenza A and B, respectively. Of the 1,010 specimens that were positive for virus isolation, 370 (36.6%) were A(H1N1)pdm09, 327 (32.4%) were A(H3N2), 130 (12.9%) B(Victoria), and 183 (18.1%) were B(Yamagata) viruses. Our data showed that influenza epidemics mainly occurred during the rainy season in Myanmar. Our three study sites, Yangon, Pyinmana, and Pyin Oo Lwin had similar seasonality and circulating type and subtype of influenza in a given year. Moreover, viruses circulating in Myanmar during the study period were closely related genetically to those detected in Thailand, India, and China. Phylogeographic analysis showed that A(H1N1)pdm09 viruses in Myanmar originated from Europe and migrated to other countries via Japan. Similarly, A(H3N2) viruses in Myanmar originated from Europe, and disseminated to the various countries via Australia. In addition, Myanmar plays a key role in reseeding of influenza B viruses to Southeast Asia and East Asia as well as Europe and Africa. Thus, we concluded that influenza virus in Myanmar has a strong link to neighboring Asian countries, Europe and Oceania. [ABSTRACT FROM AUTHOR]

The effects of friction are critical to the dynamics of electric power steering (EPS). On the one hand, friction contributes to the stability of the system and filters some of the disturbances (road vibration, etc.). On the other hand, it negatively affects the driving feel and refrains from accurate positioning of the steering wheel. In addition, for steering manufacturers, friction hinders the development and tuning of the assistance strategy. Therefore, controlling or eventually suppressing friction in EPS is a real challenge. In this paper, a control strategy for the active compensation of friction in a column-assist-type EPS is presented. The assist motor and the electronic control unit are used to cancel the friction effect in order to imitate the behavior of an ideal frictionless system. The feasibility of this strategy is demonstrated on the power column (the upper part of the steering system) using the same information (signals) as that available in an actual product. The proposed control is based on a model of the power column including slip-and load-dependent friction forces. For this purpose, a detailed simulation model, developed and validated in a previous work, is reduced to a lower order model to enable real-time computation. The LuGre model is used to compute both the static and dynamic friction forces with continuous formulation. The control architecture is composed of two cascaded feedback loops. The internal loop estimates the internal friction of the system and compensates for it through the motor input. The external loop contains a frictionless reference model used as a trajectory planner and a linear controller, which attempts to minimize the error between the plant and the reference responses. The stability and the robustness of the control strategy are formally analyzed. Specifically, it is shown that the limit error between the plant and the reference responses can be made arbitrarily small with appropriate values of the gains. Experimental results demonstrate that the control strategy is successful in tracking the frictionless reference trajectory, and confirm the robustness against inaccurate friction parameters. [ABSTRACT FROM PUBLISHER]

The majority of human group A rotaviruses possess the P[8] VP4 genotype. Recently, a genetically distinct subtype of the P[8] genotype, also known as OP354-like P[8] or lineage P[8]-4, emerged in several countries. However, it is unclear for how long the OP354-like P[8] gene has been circulating in humans and how it has spread. In a global collaborative effort 98 (near-)complete OP354-like P[8] VP4 sequences were obtained and used for phylogeographic analysis to determine the viral migration patterns. During the sampling period, 1988–2012, we found that South and East Asia acted as a source from which strains with the OP354-like P[8] gene were seeded to Africa, Europe, and North America. The time to the most recent common ancestor (TMRCA) of all OP354-like P[8] genes was estimated at 1987. However, most OP354-like P[8] strains were found in threemain clusters with TMRCAs estimated between 1996 and 2001. The VP7 gene segment of OP354-like P[8] strains showed evidence of frequent reassortment, even in localized epidemics, suggesting that OP354-like P[8] genes behave in a similar manner on the evolutionary level as other P[8] subtypes. The results of this study suggest that OP354-like P[8] strains have been able to disperse globally in a relatively short time period. This, in combination with a relatively large genetic distance to other P[8] subtypes, might result in a lower vaccine effectiveness, underscoring the need for a continued surveillance of OP354-like P[8] strains, especially in countries where rotavirus vaccination programs are in place. [ABSTRACT FROM AUTHOR]

Gathering information on the diet composition of baleen whales at different temporal scales is useful for investigating their feeding habits. Bryde's whales (Balaenoptera edeni) and sei whales (B. borealis) are known to feed on crustaceans and pelagic fish in their western North Pacific feeding grounds; however, their feeding habits before arriving in the feeding area are not known. This study clarified the feeding habits of these two whale species by simultaneously analyzing nitrogen and carbon stable isotope ratios and stomach contents of individuals captured in the western North Pacific in 2015 and 2016. A stable isotope Bayesian mixed-model was used to estimate prey composition. The results showed clear temporal differences in the feeding habits of both whales. Specifically, Bryde's whales fed primarily on krill and pelagic and mesopelagic fishes as they migrated northwards, and then fed exclusively on krill during the summer. Sei whales fed on copepods when they arrived in the subarctic region before shifting to pelagic fish species in the summer. The differences in the feeding habits of these two whale species are attributed to their latitudinal segregation and the availability of prey species, especially in sei whales, which migrate to the subarctic region where copepods are abundant. • Feedings of North Pacific Bryde's and sei whales. • Different time scales of feeding habits from stomach contents and stable isotope. • δ13C and δ15N were used in the stable isotope analysis. • Feeding habits differed depending on the analytical methods. • Whales change their feeding habits within a season. [ABSTRACT FROM AUTHOR]

The article presents the Report of the Sub-Committee on the Revised Management Procedure (RMP) of the International Whaling Commission (IWC) about its agendas and other issues discussed at the IWC Scientific Committee Annual Meeting in Agadir, Morocco from May 30 to June 11, 2010. An update on the Third Intersessional Workshop on the Review of Maximum Sustainable Yield Rate (MSYR) for Baleen Whales in Seattle, Washington in April 2010 is provided. The sub-committee decided that the range for MSYR values in the RMP should be finalised first before completing discussions on amendments to the Catch Limit Algorithm (CLA). Other topics include the sub-committee's work plan for the 2011 Annual Meeting and its recommended changes to abundance estimates for Central North Atlantic minke whales.

A study of common minke and Bryde's whales was conducted in the western North Pacific in the 2000 and 2001 summer seasons to estimate prey selection of cetaceans as this is an important parameter in ecosystem models. Whale sighting and sampling surveys and prey surveys using quantitative echosounder and mid-water trawl were carried out concurrently in the study. Biomasses of Japanese anchovy, walleye pollock and krill, which were major prey species of common minke and Bryde's whales, were estimated using an echosounder. The results suggested that common minke whale showed prey selection for Japanese anchovy while they seemed to avoid krill in both the offshore and coastal regions and walleye pollock in the continental shelf region. Selection for shoaling pelagic fish was similar to that in the eastern North Atlantic. Bryde's whale showed selection for Japanese anchovy in August 2000 and July 2001, while it showed prey selection for krill in May and June in 2001. [ABSTRACT FROM AUTHOR]

The forestomach contents of 498 minke whales Balaenoptera acutorostrata sampled in the Northwestern Pacific from May to September through the 1994–1999 JARPN surveys, were analysed. Sixteen prey species consisting of 1 copepod, 4 euphausiids, 1 squid, and 10 fishes were identified. The minke whale in the Northwestern Pacific is a swallowing, feeding-type species. It feeds on swarming zooplankton and schooling fishes, suggesting that minke whales pursue single prey-species aggregations. The results showed geographical and seasonal changes of prey species. On the Pacific side of Japan, Japanese anchovy was the most important prey species in May and June, while Pacific saury was most important in July and August. Walleye pollock was also an important prey species during June and September in coastal waters, over the continental shelf. In the southern Okhotsk Sea krill was the most important prey species in July and August. These changes probably reflect changes in the availability of the prey species in these areas. It would seem that there might be direct competition between minke whales and the fishery for Pacific saury. Copyright 2002 International Council for the Exploration of the Sea. Published by Elsevier Science Ltd. All rights reserved. [Copyright &y& Elsevier]

The case of a symptomatic fifty-four-year-old woman with a huge, solitary aneurysm of the right coronary artery is presented. A coronary angiogram did not visualize the aneurysm because of tightly packed thrombi in it, but it was definitely diagnosed intraoperatively after the mass was opened. Excision of the aneusymal wall, removal of thrombi, closure of coronary ostium, and plication of the aneurysmal wall were performed without revascularization. Histologic ex aminations demonstrated cystic medial necrosis with deposition of acid- mucopolysaccharides, suggesting that pathogenesis might be a dissecting aneurysm. [ABSTRACT FROM PUBLISHER]

The authors describe a case with an internal mammary artery (IMA) graft that demonstrated prolonged, but reversible, luminal narrowing persisting > twenty-four hours following percutaneous transluminal angioplasty. Luminal narrowing disappeared spontaneously, however, at the time of follow-up angiography one week after the angioplasty. Since haziness at the dilation site had been shown on preprocedural angiogram, suggestive of intraluminal thrombus, this phenomenon may be attributed to either prolonged vasospasm or distal embolization of the IMA graft. [ABSTRACT FROM AUTHOR]