Season In Japan Research Articles

Application of principle component Analysis in differentiating the three types of Amaranthus based on their photoperiodic flowering response

Response of flowering has become an attracting field for plant breeders and is pre-requisite in plant introduction process from different ecogeographical origins. Time of flowering is mostly induced by the day-length or photoperiod and temperature. Amaranth (Amaranthus sp.) is known as multipurpose plants and utilized as grains or as vegetables. Under tropical environment, likewise in Indonesia, the requirement of day-length to induce flowering in amaranths is unrevealed as the day-length remains always constant with approximately 12 hours per day. During the introduction of amaranth to Japan, we would like to confirm the type of amaranth, which in general has been theoretically classified as short day plants. Under the variation of day-length ranging from 9 up to 15 hours during the four seasons in Japan, thus, we confirmed that amaranth as short day plants. Although, the vegetable ones required day-length up to 12 hours. Such conclusion was obtained from the flowering response of 69 accessions representing amaranth’s eco-geographical variations within two consecutive years. Seeds were sown in two replicates. Plant nursery was conducted on the Norin-Ijutsu Centre belongs to the University of Tsukuba. Mean values from two replicates were obtained and the average was then further subjected to Principle Component Analysis (PCA) [JMP ver. 7.0 (SAS Institute, USA)]. Thus, PCA was able to differentiate the flowering tendency within the three types of amaranths in the form of three ellipsoids. A post-publication change was made to this article on 11 Mar 2020 to correct the conference title in the PDF header.

Distribution of 58 Semi-Volatile Organic Chemicals in the Gas Phase and Three Particle Sizes in Indoor Air and House Dust in Residential Buildings During the Hot Season in Japan

Distribution of 58 Semi-Volatile Organic Chemicals in the Gas Phase and Three Particle Sizes in Indoor Air and House Dust in Residential Buildings During the Hot Season in Japan

Modelling the optimal target age group for seasonal influenza vaccination in Japan

BackgroundIn Japan, the current influenza vaccination programme is targeting older individuals. On the other hand, epidemics of influenza are likely to be mainly driven by children. In this study, we consider the most cost-effective target age group for a seasonal influenza vaccination programme in Japan. MethodsWe constructed a deterministic compartmental Susceptible-Exposed-Infectious-Recovered (SEIR) model with data from the 2012/13 to 2014/15 influenza seasons in Japan. Bayesian inference with Markov Chain Monte Carlo method was used for parameter estimation. Cost-effectiveness analyses were conducted from public health care payer’s perspective. ResultsA scenario targeting children under 15 was expected to reduce the number of cases 6,382,345 compared to the current strategy. A scenario targeting elderly population (age over 49 years) was expected to reduce the number of cases 693,206. The children targeted scenario demonstrated negative ICER (incremental cost-effectiveness ratio) value. On the other hand, elderly targeted scenario demonstrated higher ICER value than the willingness to pay (50,000 USD/QALY). ConclusionsA vaccination programme which targets children under 15 is predicted to have much larger epidemiological impact than those targeting elderly.

Seasonality of newly notified pulmonary tuberculosis in Japan, 2007\u20132015

BackgroundThe seasonality of pulmonary tuberculosis (TB) incidence may indicate season-specific risk factors that could be controlled if they were better understood. The aims of this study were to elucidate how the incidence of TB changes seasonally and to determine the factors influencing TB incidence, to reduce the TB burden in Japan.MethodsWe assessed the seasonality of newly notified TB cases in Japan using national surveillance data collected between 2007 and 2015. To investigate age and sex differences, seasonal variation was analyzed according to sex for all cases and then by stratified age groups (0–4, 5–14, 15–24, 25–44, 45–64, 65–74, and ≥ 75 years). We used Roger’s test to analyze the cyclic monthly trends in seasonal variation of TB incidence.ResultsA total of 199,856 newly notified TB cases (male, 62.2%) were reported over the past 9-year period. Among them, 60.6% involved patients aged ≥65 years. Overall, the peak months of TB incidence occurred from April to October, excluding September. In the analysis stratified by age group, a significant seasonal variation in TB cases was observed for age groups ≥15 years, whereas no seasonal variation was observed for age groups ≤14 years. For female patients aged ≥25 years, the peak TB epidemic period was seen from June to December, excluding November. Male patients in the same age groups exhibited declining TB incidence from September to March.ConclusionsTB incidence exhibits seasonality in Japan for people aged > 15 years and peaks in summer to fall. Monthly trends differ according to age and sex. For age groups ≥25 years, cases in women showed longer peaks from June to December whereas cases in men declined from September to December. These results suggest that the seasonality of TB incidence in Japan might be influenced by health checkups in young adults, reactivation of latent TB infection with aging, and lifestyle habits in older adults. These findings can contribute to establishing the potential determinants of TB seasonality in Japan.

Predicting Directions of Changes in Genotype Proportions Between Norovirus Seasons in Japan.

The norovirus forecasting system (NOROCAST) has been developed for predicting directions of changes in genotype proportions between human norovirus (HuNoV) seasons in Japan through modeling herd immunity to structural protein 1 (VP1). Here 404 nearly complete genomic sequences of HuNoV were analyzed to examine whether the performance of NOROCAST could be improved by modeling herd immunity to VP2 and non-structural proteins (NS) in addition to VP1. It was found that the applicability of NOROCAST may be extended by compensating for unavailable sequence data and observed genotype proportions of 0 in each season. Incorporation of herd immunity to VP2 and NS did not appear to improve the performance of NOROCAST, suggesting that VP1 may be a suitable target of vaccines.

Effectiveness of Power Point Media in 4 Seasons as the Sakura Culture Festival

Culture festival of the cherry country or what is called the “Matsuri” has many and varied, that is why in every place in Japan has its own cultural festival. The Japanese cultural festival has high values for its visitors or we can conclude that the Japanese cultural festival is an activity of exchange of values to uphold the customs of their existence. Japanese cultural festivals follow the 4 seasons in Japan, namely spring (haru), summer (natsu), autumn (aki) and winter (fuyu). These 4 seasons are a technology for Japanese people and are very influential in their cultural festivals. Many festivals occur and follow the 4 seasons in Japan, and the most interesting, with the emergence of the most popular festivals, and only occur every season, namely the spring festival hanami (haru), the summer festival tanabata (natsu), momiji festival in the autumn (aki) and Sapporo festival in winter (fuyu). In this research, researchers will discuss Japanese culture festivals that affect 4 seasons in Japan. Where the researchers will introduce it through existing power point slide media. In this research, the effectiveness of power point slide media in 4 seasons as Sakura’s cultural festival, will use qualitative research methods, namely a contextual study that makes humans as instruments, and adapted to a reasonable situation in relation to data collection which is generally qualitative. This research took place at the Manado State Polytechnic Department of Business Administration. Sources of data are primary, namely data taken directly at the student. While secondary data is a literature study and Japanese language curriculum. Data collection techniques are observation and research questionnaire. The data analysis technique is an effort to systematically search and organize the results of observations and dissemination of questionnaires to improve researchers’ understanding of the findings based on the problems studied. The results of this study are research instruments in the form of questionnaires with 9 questions, 3 options given 1 - 3 and number of respondents 143 people. Each item gets the highest score, and the result = 3 × 9 × 143 = 3861. For the highest score that is = 3, with the number of items = 9 and the number of respondents = 143. The total score of the answers from 143 respondents is = 3264. Thus it can be seen the percentage value according to the perception of 143 respondents is = 3264: 3861 × 100 = 84.5%. From the results of data processing with each question, with the number of respondents 143, declared valid. This research aims to enable students to recognize Japanese characters, students can get to know Japanese customs; students can get to know Japanese culture and what Japan is like. Students can get to know the cultural festival at 4 seasons in Japan through an existing learning media, namely power point media. The students are not only taught Japanese language education, but get an introduction to Japanese culture.

An Investigation of the Behavioral Characteristics of Higher- and Lower-Temperature Group Families in a Condominium Equipped with a HEMS System

A home energy management system (HEMS) shows the energy used indoors so that the energy waste can be easily identified and reduced. Thermal comfort is related to the trend of energy use in buildings. We conducted a survey in a condominium equipped with a HEMS to determine the indoor thermal environment and various behaviors of the occupants taken for thermal comfort adjustment. The results showed that there is a large variation of indoor air temperatures according to season, floor and flat. We categorized families into two groups, one with higher and the other with lower average indoor temperatures. The indoor air temperature of the higher temperature group in summer was found to be higher than the recommended indoor temperature during the summer season in Japan. The higher temperature group tended to adopt behaviors, such as window opening and using a fan more often, than the lower temperature group. Due to the moderately high insulating levels in the building surveyed, the indoor air temperature of both groups was not low in winter. Heating was used less and irregular. The overall results indicate that the groups of families behaved differently to adjust the indoor thermal environment even though they were equipped with the same HEMS system.

Susceptibility of Influenza Viruses to the Novel Cap-Dependent Endonuclease Inhibitor Baloxavir Marboxil.

The novel cap-dependent endonuclease inhibitor baloxavir marboxil was approved for the treatment of influenza A and B virus infections in February 2018 in Japan. Because of the need to monitor influenza viruses for reduced susceptibility to this drug, we used two cell-based screening systems – a conventional plaque reduction assay and a focus reduction assay – to evaluate the susceptibility of influenza viruses to baloxavir. First, we generated a reference virus possessing an I38T substitution in the polymerase acidic subunit (PA), which is known to be associated with reduced susceptibility to baloxavir, and demonstrated the validity of our systems using this reference virus. We then determined the susceptibility of a panel of neuraminidase (NA) inhibitor-resistant viruses and their sensitive counterparts to baloxavir. No significant differences in baloxavir susceptibilities were found between the NA inhibitor-resistant and -sensitive viruses. We also examined seasonal influenza viruses isolated during the 2017–2018 influenza season in Japan and found that no currently circulating A(H1N1)pdm09, A(H3N2), or B viruses had significantly reduced susceptibility to baloxavir and none of the viruses possessed an amino acid substitution at PA residue 38. Use of a combination of methods to analyze antiviral susceptibility and detect amino acid substitutions is valuable for monitoring the emergence of baloxavir-resistant viruses.

Influenza vaccine showed a good preventive effect against influenza-associated hospitalization among elderly patients, during the 2016/17 season in Japan.

The 2016/17 influenza season in Japan was characterized by a predominance of influenza A (H3N2) activity; with H3N2 accounting for 85% of all detected influenza virus infections. We assessed the vaccine effectiveness (VE) of an inactivated quadrivalent influenza vaccine (IIV4) in adult patients, using a test-negative case-control design study based on the results of a rapid influenza diagnostic test (RIDT). Between November 2016 and March 2017, a total of 1048 adult patients were enrolled: including 363 RIDT positive for influenza A, 9 RIDT-positive for influenza B, and 676 RIDT-negative. During the 2016/17 season, the overall adjusted VE was 28.8% (95% confidence interval [CI]: 6.3-46%). The adjusted VE against influenza A was 27.4% (95%CI: 4.4-45%). The VE against influenza B could not be estimated because of the very low number of influenza B patients. Twenty-nine patients were hospitalized due to influenza-associated illness-during the present study, all of whom were infected with influenza A virus. The adjusted VE, determined using a case-control study, for preventing hospitalization for influenza A infection was 72.6% (95%CI: 30.7-89.1%). In addition, the VE for preventing hospitalization of influenza patients with comorbidities was 78.2% (95%CI: 41.1-92%). Our study showed that, during the 2016/17season, IIV4 was effective for preventing both the onset of influenza and influenza-associated hospitalization.

Household transmission of acute gastroenteritis during the winter season in Japan

ObjectivesAcute gastroenteritis, including illness caused by norovirus, is sometimes transmissible among susceptible persons who experience close contact, including those within a household, and it disturbs social activities of patients and their family. However, epidemiological assessment of the transmissibility and its heterogeneity has not been conducted. The present study aimed to quantify the frequency of household transmission that was likely caused by norovirus, and characterize its determinants.MethodsA household survey was conducted, analyzing the history of suspected norovirus infection from January to March, 2017. Noro-like illness was clinically defined as a patient with either: (i) diarrhea or vomiting multiple times a day; or (ii) diarrhea or vomiting persisting for 2 or more days.ResultsAmong 380 households, 132 households (34.7%) were eligible for epidemiological analysis, with an estimated secondary attack risk of 13.8% (38/276). Age-specific secondary attack risk was highest among index case patients aged 0 to 14 years (25.8%). The prevalence of vomiting in this age group was higher than in other age groups, with an odds ratio of household transmission estimated at 4.3.ConclusionsAge-dependent heterogeneity was successfully identified, offering critical insights into future considerations for norovirus control at various social settings.

The Effects of Low Air Temperatures on Thermoregulation and Sleep of Young Men While Sleeping Using Bedding

Most people do not use heating systems during nocturnal sleep in their bedrooms during the cold season in Japan; instead, they like to use extra blankets and quilts for sleeping. To investigate the effect of low air temperature (Ta) on sleep and thermoregulation when sleeping with bedding, 12 healthy young men participated in sleep experiments over three non-consecutive nights. The experimental conditions were at a Ta of 3 °C, 10 °C and 17 °C, with a relative humidity (Rh) of 50% and an air velocity of <0.2 m/s in the climatic chambers. The 4.3-clo bedding consisted of cotton sheets, an acrylic blanket, a down-filled quilt and a futon mattress. The average sleep efficiency index (SEI) remained >94% for each of the three Tas, and no disturbances were found by Ta in the sleep parameters, although the duration of rapid eye movement (REM) sleep showed variations at 3 °C. The skin temperature (Ts) of the forehead decreased in proportion to Ta and remained stable. The decreasing rate in rectal temperature (Tre), Ts of forehead and thigh during sleep were significantly greater at 3 °C than at 10 °C and 17 °C. The innermost microclimate temperature (Tmicro) made by the bedding did not correlate with the Tre. The young men were significantly more dissatisfied with 3 °C in the sleep quality evaluation.

Clinical effectiveness of four neuraminidase inhibitors (oseltamivir, zanamivir, laninamivir, and peramivir) for children with influenza A and B in the 2014-2015 to 2016-2017 influenza seasons in Japan.

The clinical effectiveness of four neuraminidase inhibitors (NAIs) (oseltamivir, zanamivir, laninamivir, and peramivir) for children aged 0 months to 18 years with influenza A and B were investigated in the 2014-2015 to 2016-2017 influenza seasons in Japan. A total of 1207 patients (747 with influenza A and 460 with influenza B) were enrolled. The Cox proportional-hazards model using all of the patients showed that the duration of fever after administration of the first dose of the NAI was shorter in older patients (hazard ratio=1.06 per 1 year of age, p<0.001) and that the duration of fever after administration of the first dose of the NAI was shorter in patients with influenza A infection than in patients with influenza B infection (hazard ratio=2.21, p<0.001). A logistic regression model showed that the number of biphasic fever episodes was 2.99-times greater for influenza B-infected patients than for influenza A-infected patients (p<0.001). The number of biphasic fever episodes in influenza A- or B-infected patients aged 0-4 years was 2.89-times greater than that in patients aged 10-18 years (p=0.010), and the number of episodes in influenza A- or B-infected patients aged 5-9 years was 2.13-times greater than that in patients aged 10-18 years (p=0.012).

Health risks and precautions for visitors to the Tokyo 2020 Olympic and Paralympic Games.

In 2020, Japan will host the Tokyo Olympic and Paralympic Games in 2020 (Tokyo 2020) which will involve a large population influx from various countries to Tokyo, the most populated city in Japan. We summarize the potential health risks for visitors to Tokyo 2020, related to communicable disease risks and other health threats, based on recent national and local surveillance reports. We reviewed up-to-date surveillance reports published by the National Institute of Infectious Diseases and Tokyo Metropolitan Infectious Disease Surveillance Center. Communicable disease risks for vaccine-preventable illnesses such as measles and rubella, as well as food and waterborne diseases represent the most likely risks. The risk of acquiring vector-borne diseases is considered low in Japan. On the other hand, however, heat-related illness represents a potential risk, as Tokyo 2020 is scheduled during the hottest season in Japan, with temperatures generally expected to exceed 30 °C. Maintaining an up-to-date routine vaccination schedule is highly recommended for visitors attending the Tokyo 2020 and appropriate hygiene measures for food and waterborne diseases as well as health promotion for heat-related illness. It may also be useful to increase the number of multilingual triage clinicians whom can be placed within emergency departments during the Tokyo 2020 to provide first contact services and coordination of emergency care among non-Japanese speaking visitors to Tokyo.

Genetic Analysis of Human Norovirus Strains in Japan in 2016-2017.

In the 2016/2017 winter season in Japan, HuNoV GII.P16-GII.2 strains (2016 strains) emerged and caused large outbreaks of acute gastroenteritis. To better understand the outbreaks, we examined the molecular evolution of the VP1 gene and RdRp region in 2016 strains from patients by studying their time-scale evolutionary phylogeny, positive/negative selection, conformational epitopes, and phylodynamics. The time-scale phylogeny suggested that the common ancestors of the 2016 strains VP1 gene and RdRp region diverged in 2006 and 1999, respectively, and that the 2016 strain was the progeny of a pre-2016 GII.2. The evolutionary rates of the VP1 gene and RdRp region were around 10-3 substitutions/site/year. Amino acid substitutions (position 341) in an epitope in the P2 domain of 2016 strains were not found in pre-2016 GII.2 strains. Bayesian skyline plot analyses showed that the effective population size of the VP1 gene in GII.2 strains was almost constant for those 50 years, although the number of patients with NoV GII.2 increased in 2016. The 2016 strain may be involved in future outbreaks in Japan and elsewhere.

Phylogeny and Immunoreactivity of Norovirus GII.P16-GII.2, Japan, Winter 2016-17.

During the 2016–17 winter season in Japan, human norovirus GII.P16-GII.2 strains (2016 strains) caused large outbreaks of acute gastroenteritis. Phylogenetic analyses suggested that the 2016 strains derived from the GII.2 strains detected during 2010–12. Immunochromatography between 2016 strains and the pre-2016 GII.2 strains showed similar reactivity.

Clinical Differences in Hospitalized Adult Influenza Patients between the A (H1N1) pdm09 and the A (H3N2) Seasons in Japan

To determine the differences in the clinical features of hospitalized elderly patients with influenza between the A (H1N1) pdm09 and the A (H3N2)-dominant seasons, 12 adult patients (mean age, 76.5 years) with influenza who were hospitalized during the 2015-2016 A (H1N1) pdm09-dominant season were compared with 26 adult patients (mean age, 82.5 years) with influenza who were hospitalized during the 2016-2017 A (H3N2)-dominant season. Compared with the A (H3N2)-dominant 2016-2017 season, the A (H1N1) pdm09-dominant 2015-2016 season had fewer non-survivors, but had significantly fewer patients who required oxygenation/respirator support and intravenous anti-influenza agents, such as peramivir. Among the severe patients who received oxygenation/respirator support, the outcomes were better in the A (H3N2)-dominant 2016-2017 season than in the A (H1N1) pdm09-dominant 2015-2016 season. The pneumonia types and detected bacteria did not differ between the two seasons, but the use of sulbactam/ampicillin was more frequent in the A (H1N1) pdm09-dominant 2015-2016 season than in the A (H3N2)-dominant 2016-2017 season. These data suggest that peramivir treatment and oxygenation/respirator support, but not sulbactam/ampicillin administration, may improve the outcome of severe elderly patients hospitalized for influenza, especially the A (H3N2) type.

Detection of Saffold viruses from children with acute respiratory infections in Yamagata, Japan, between 2008 and 2015.

Although Saffold virus (SAFV) was reported as a novel human cardiovirus in 2007, no causative association between SAFV and clinical disease has been proven and the longitudinal epidemiology of SAFVs is not available. To establish the relationship between SAFVs and acute respiratory infections (ARIs) and to clarify the longitudinal epidemiology of SAFVs, 7258 nasopharyngeal specimens were collected from children with ARIs in Yamagata, Japan between 2008 and 2015. The specimens were inoculated on a microplate including six cell lines as part of routine surveillance, and molecular screening was performed for SAFVs using a reverse transcription (RT)-PCR method. Throughout the study period, 95 (1.3%) SAFV genotype 2 (SAFV2), and 28 (0.4%) SAFV3 were detected, mainly between September and November. There were two outbreaks of SAFV2 in 2009 and 2013, and one outbreak of SAFV3 in 2012 and the positive rates during these outbreaks were 12.1% (53/439), 11% (35/319), and 4.4% (20/453), respectively. Sixty-three SAFV2 and 28 SAFV3 strains were detected as a single virus from children with ARIs such as pharyngitis, herpangina, and tonsillitis. These results suggested that SAFV2 and SAFV3 are possible causative agents of ARIs among children and their infections occur mainly in the autumn season in Japan.

Influenza vaccine effectiveness in adults based on the rapid influenza diagnostic test results, during the 2015/16 season.

We assessed the influenza vaccine effectiveness (VE) of an inactivated quadrivalent influenza vaccine in adult patients, in our test-negative case-control design study based on the results of a rapid influenza diagnostic test. During the 2015/16 season in Japan, influenza A(H1N1)pdm09 virus and influenza B virus were epidemic. The overall adjusted VE was 44% (95% confidence interval [CI]: 13.6%-63.7%). The adjusted VE was 52.9% (95%CI: 20%-72.3%) against any influenza virus among those<65 years of age and -5% (95%CI: 136%-53.5%) among the elderly ≧ 65 years of age. The adjusted VE against influenza A was 49.1% (95%CI: 13.9%-69.9%). Although the VE was 55.5% (95%CI: 14.8%-76.8%) among those <65 years of age, it was only 15.3% (95%CI: 120%-67.4%) among the elderly ≧ 65 years of age. The adjusted VE against influenza B was 33.8% (95%CI: 25%-64.8%) among adult patients (≧16 years of age) and 46.8% (95%CI: 13%-75%) among those<65 years of age, the VE against influenza B could not be estimated in those ≧65 years of age because of the low number of elderly patients with that virus.

2017 Global Conference on Polymer and Composite Materials (PCM 2017)

PCM2017 PrefaceThe 2017 Global Conference on Polymer and Composite Materials (PCM 2017), sponsored by Wuhan Advanced Materials Society, was held from May 23 – 25, 2017 in Guangzhou, China. The technical program consisted of 4 international keynote speakers, 62 invited speakers, 40 oral presentations, and a poster session with 42 works. The conference had parallel sessions with dedicated selected subjects related to Polymers and Composite Materials.The present issue of IOP Conference Series: Materials Science and Engineering (MSE) records the proceedings of PCM 2017 and contains 50 specially selected manuscripts submitted to the PCM2017 conference. The electronic submission and handling of manuscripts via the conference website, including the selection of reviewers and evaluation of manuscripts, were identical to the procedures applied to manuscripts submitted as regular contributions for international per-reviewed publications.The organization of this conference and the preparation of proceedings volume would have been impossible without the tremendous efforts and dedication of many individuals, especially from Ms. Yajun Ye, who oversaw the organization of the conference and the program, and a large team of reviewers with their timely submission of quality reports. We express our sincere thanks to all authors and presenters for their contributions. We also thank very much our sponsors for their generous support.The 2018 Global Conference on Polymer and Composite Materials (PCM2018) will be held during April 10-13, 2018, in Kitakyushu City, Japan. This is the best period to catch the Sakura Season in Japan. Located in the west of Japan, the city is situated conveniently close to many rapidly developing East Asian countries. With views over the Sea of Japan and the Seto Inland Sea, and with forty percent of the city's area comprised of rich forest, it is a city blessed with an abundance of nature. Being one of the four main industrial areas of Japan, Kitakyushu City has made great contributions towards the modernization of Japanese industry. Kitakyushu City's many notable attractions include Kokura Castle, the port town of Mojiko Retro, the Hiraodai Limestone Plateau (one of the three major karst plateaus of Japan), and many leisure facilities. Kitakyushu City also has a vast menu of appetizing dishes, such as Kokura beef, and Yaki-udon, as well as many other delicacies harvested from the mountains and sea.All participants are welcome to the renewed and vibrant PCM2018! More information will be available at the conference website: www.cpcmconf.org.Prof. Dr. Esteban BroitmanGeneral Chairman PCM2017Linköping, Sweden, June 2017

Predictability of meso‐γ‐scale, localized, extreme heavy rainfall during the warm season in Japan using high‐resolution precipitation nowcasts

The development and verification of a forecast method for localized, meso‐γ‐scale (2–20 km), extreme heavy rainfall (MγExHR) is important, because it can cause urban flash flooding and inundation with accompanying damage and potential loss of life. Although previous studies have examined the predictability of precipitation at a very short range (≤1 h) using extrapolation‐based nowcasts, they did not specifically focus on MγExHR. In this study, we examine the predictability of 23 selected events of MγExHR (1 h rainfall accumulation ≥50 mm) that occurred during the warm season of 2014 in Japan using High‐Resolution Precipitation Nowcasts (HRPNs) provided by the Japan Meteorological Agency, which are extrapolation‐based nowcasts. Traditional grid‐scale verification using the equitable threat score shows that the HRPNs usefully predict the heavy rainfall areas of ≥20 mm h−1 for at least 12 min at the grid scale of 1 km. Neighbourhood verification using fractions skill scores shows that HRPNs usefully predict the areas of ≥20 mm h−1 up to 29 min by tolerating 11 km displacement errors. After 30 min, a useful forecast cannot be obtained, even if the 11 km displacement errors are tolerated for the ≥20 mm h−1 areas. This result suggests that a numerical weather prediction (NWP) model, whose accuracy is useful after ∼30 min, is necessary to seamlessly provide useful forecasts for heavy rainfall areas of ≥20 mm h−1 for MγExHR with ∼10 km displacement errors, by blending the extrapolation‐based nowcast with NWP.