Yoshifumi Masago

Dr. Yoshifumi Masago

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 2018 in Water Research
Verified
Journal Article
Open access
Eiji HaramotoEiji Haramoto
Eiji Haramoto
Masaaki KitajimaMasaaki Kitajima
Masaaki Kitajima
AHAkihiko Hata
Akihiko Hata
JTJason R. Torrey
Jason R. Torrey
YMYoshifumi Masago
Yoshifumi Masago
KHKatayama Hiroyuki
Katayama Hiroyuki
Waterborne human enteric viruses, such as noroviruses and adenoviruses, are excreted in the feces of infected individuals and transmitted via the fecal-oral route including contaminated food and water. Since viruses are normally present at low concentrations in aquatic environments, they should be concentrated into smaller volumes prior to downstream molecular biological applications, such as quantitative polymerase chain reaction (qPCR). This review describes recent progress made in the development of concentration and detection methods of human enteric viruses in water, and discusses their applications for providing a better understanding of the prevalence of the viruses in various types of water worldwide. Maximum concentrations of human enteric viruses in water that have been reported in previous studies are summarized to assess viral abundances in aquatic environments. Some descriptions are also available on recent applications of sequencing analyses used to determine the genetic diversity of viral genomes in water samples, including those of novel viruses. Furthermore, the importance and significance of utilizing appropriate process controls during viral analyses are discussed, and three types of process controls are considered: whole process controls, molecular process controls, and (reverse transcription (RT)-)qPCR controls. Although no standards have been established for acceptable values of virus recovery and/or extraction-(RT-)qPCR efficiency, use of at least one of these appropriate control types is highly recommended for more accurate interpretation of observed data.

1 July 2010 in Water Research
Verified
Journal Article
Closed access
TTTomoko Takaara
Tomoko Takaara
DSDaisuke Sano
Daisuke Sano
YMYoshifumi Masago
Yoshifumi Masago
TOTatsuo Omura
Tatsuo Omura

1 April 2016 in Water Research
Verified
Journal Article
Closed access
Shinobu KazamaShinobu Kazama
Shinobu Kazama
YMYoshifumi Masago
Yoshifumi Masago
KTKentaro Tohma
Kentaro Tohma
NSNao Souma
Nao Souma
TIToshifumi Imagawa
Toshifumi Imagawa
TOTatsuo Omura
Tatsuo Omura

29 October 2014 in Virus Genes
Verified
Journal Article
Open access
PDF file
RMRungnapa Malasao
Rungnapa Malasao
MSMayuko Saito
Mayuko Saito
ASAkira Suzuki
Akira Suzuki
TIToshifumi Imagawa
Toshifumi Imagawa
NNNao Nukiwa-Soma
Nao Nukiwa-Soma
HOHitoshi Oshitani
Hitoshi Oshitani
Two novel G3P[4] rotavirus strains were detected from children with acute diarrhea in Sendai, Japan, identified as a G3–P[4]–I2–R2–C2–M2–A2–N2–T2–E2–H2 genotype constellation by whole-genome sequence analysis. The VP7 gene of the two strains displayed the highest nucleotide sequence identity (91 %) and showed a close genetic relationship (99 % bootstrap value) to an equine rotavirus reported in India. The other gene segments were related to human group A rotaviruses. This report suggests a possible reassortment event between human and equine rotaviruses.

29 November 2016 in Water
Verified
Journal Article
Open access
PDF file
AEAmmar Rafiei Emam
Ammar Rafiei Emam
BMBinaya Kumar Mishra
Binaya Kumar Mishra
Pankaj KumarPankaj Kumar
Pankaj Kumar
YMYoshifumi Masago
Yoshifumi Masago
KFKensuke Fukushi
Kensuke Fukushi
The hydrological conditions upstream of the Ciliwung watershed are changing due to climate and land-use changes. Any changes in this area may increase the flood frequencies which may have countless consequences downstream of the watershed where the Jakarta city is located. We simulated the effects of land-use and climate changes on flooding (e.g., peak flow and river discharge) in the upper Ciliwung River basin in Greater Jakarta, Indonesia. Hydrologic Modeling System (HEC-HMS), a rainfall-runoff simulation model, was used to simulate peak river discharge values for current and future conditions. The model was calibrated and validated based on the observed river discharge data from February 2007 and January 1996, respectively. The statistical analysis showed that the performance of the model is satisfactory, with Nash–Sutcliffe efficiency 0.64 and 0.58 for calibration and validation, respectively. The coefficients of determination values are 0.86 and 0.82, respectively. The effect of the projected land-use changes alone in 2030 increased the peak flow by approximately 20%. When considering the land-use changes in conjunction with the future climate scenario, the peak flow based on the precipitation corresponding to a 50-year return period in 2030 increased by 130%. Based on the results of this study, it is urgent that a flood management plan be implemented in the target area to reduce flooding in the near future.

Verified
Journal Article
Open access
PDF file
MKMohamed Kefi
Mohamed Kefi
BMBinaya Kumar Mishra
Binaya Kumar Mishra
Pankaj KumarPankaj Kumar
Pankaj Kumar
YMYoshifumi Masago
Yoshifumi Masago
KFKensuke Fukushi
Kensuke Fukushi
Due to climate change, the frequency and intensity of Hydro-Meteorological disasters, such as floods, are increasing. Therefore, the main purpose of this work is to assess tangible future flood damage in the urban watershed of the To Lich River in Hanoi, Vietnam. An approach based on spatial analysis, which requires the integration of several types of data related to flood characteristics that include depth, in particular, land-use classes, property values, and damage rates, is applied for the analysis. To simulate the future scenarios of flooding, the effects of climate change and land-use changes are estimated for 2030. Additionally, two scenarios based on the implementation of flood control measures are analyzed to demonstrate the effect of adaptation strategies. The findings show that climate change combined with the expansion of built-up areas increases the vulnerability of urban areas to flooding and economic damage. The results also reveal that the impacts of climate change will increase the total damage from floods by 26%. However, appropriate flood mitigation will be helpful in reducing the impacts of losses from floods by approximately 8% with the restoration of lakes and by approximately 29% with the implementation of water-sensitive urban design (WSUD). This study will be useful in helping to identify and map flood-prone areas at local and regional scales, which can lead to the detection and prioritization of exposed areas for appropriate countermeasures in a timely manner. In addition, the quantification of flood damage can be an important indicator to enhance the awareness of local decision-makers on improving the efficiency of regional flood risk reduction strategies.