Author Fukuhara, Kazuma| Phompida, Samlane| Insisiengmay, Sithat| Kirinoki, Masashi| Chigusa, Yuichi| Nakamura, Satoshi| Matsuda, Hajime| Ishikawa, Hirofumi|
Published Date 2011-12
Publication Title Parasitology International
Volume volume60
Issue issue4
Content Type Journal Article
Author Fukutome, Ayako| Watashi, Koichi| Kawakami, Norito| Ishikawa, Hirofumi|
Published Date 2007
Publication Title Microbiology and Immunology
Volume volume51
Issue issue9
Content Type Journal Article
Author Ishikawa, Hirofumi| Ohmae, Hiroshi| Pangilinan, Rogelio| Redulla, Apolinario| Matsuda, Hajime|
Published Date 2008-03-14
Publication Title PARASITOLOGY INTERNATIONAL
Volume volume55
Issue issue1
Content Type Journal Article
Author Hisakane, Naoto| Kirinoki, Masashi| Chigusa, Yuichi| Sinuon, Muth| Socheat, Duong| Matsuda, Hajime| Ishikawa, Hirofumi|
Published Date 2008-09-03
Publication Title PARASITOLOGY INTERNATIONAL
Volume volume57
Issue issue3
Content Type Journal Article
Author Ishikawa, Hirofumi| Ohga, Yukio| Doi, Rikuo|
Published Date 2003-07-29
Publication Title Parasitology Research
Volume volume91
Issue issue6
Content Type Journal Article
Author Ishikawa, Hirofumi|
Published Date 2008-03-25
Publication Title PARASITOLOGY INTERNATIONAL
Volume volume55
Content Type Journal Article
Author Nishina, Tomohiko| Ishikawa, Hirofumi|
Published Date 2008-02-01
Publication Title Parasitology Research
Volume volume102
Issue issue3
Content Type Journal Article
JaLCDOI 10.18926/AMO/32275
FullText URL fulltext.pdf
Author Harada, Masakazu| Ishikawa, Hirofumi| Matsuoka, Hiroyuki| Ishii, Akira| Suguri, Setsuo|
Abstract <p>We developed a sensitive polymerase chain reaction (PCR) method for the detection of Plasmodium falciparum DNA from mosquitoes collected in the field. Plasmodium falciparum was detected from 15.2% of 1-parous mosquitoes, Anopheles farauti, in the Solomon Islands through use of the PCR method. A novel mathematical model was developed to estimate the sporozoite rate based on the malaria-positive rate of 1-parous mosquitoes. Using this model, the sporozoite rate of Anopheles farauti in the Solomon Islands was calculated to be 0.09%. This method enables estimation of the sporozoite rate based on a relatively small number (100-200) of mosquitoes compared with the number needed for the ELISA method.</p>
Keywords sporozoite rate polymerase chain reaction (PCR) mathematical model Anopheles Plasmodium
Amo Type Article
Published Date 2000-08
Publication Title Acta Medica Okayama
Volume volume54
Issue issue4
Publisher Okayama University Medical School
Start Page 165
End Page 171
ISSN 0386-300X
NCID AA00508441
Content Type Journal Article
language 英語
File Version publisher
Refereed True
PubMed ID 10985176
Web of Science KeyUT 000089132800004
JaLCDOI 10.18926/fest/15042
FullText URL 014_001_012.pdf
Author Morimoto, Tomoko| Zenihana, Tomohiro| Maitani, Yusuke| Ishikawa, Hirofumi|
Abstract The spread of the highly pathogenic avian influenza (H5N1) among domestic poultry and wild birds has caused global concern over the outbreak of an influenza pandemic of H5N1. The "Pandemic Influenza Preparedness Action Plan" determines the strategy against an influenza pandemic in Japan. Simulations were carried out using an individual based model (IBM). The IBM targeted a virtual area with a population of 100,000 using the demographic data of Sapporo-city, Hokkaido. The effectiveness of targeted antiviral prophylaxis (TAP), geographical targeted antiviral prophylaxis (GTAP), school closure, and pre-pandemic vaccination were explored. Moreover, this study focused on infections among children, who have a high attack rate, and analyzed the effectiveness of interventions for school-age targeted antiviral prophylaxis (STAP). Consequently, TAP, which is recommended by the "Pandemic Influenza Preparedness Action Plan", was found to have high effectiveness in the suppression of the outbreak. Moreover, this study showed the importance of intervention among children, such as STAP and school closure, to prevent the spread of H5N1 influenza.
Keywords Influenza Pandemic H5N1 Individual Based Model (IBM) Sapporo
Publication Title 岡山大学環境理工学部研究報告
Published Date 2009-03-16
Volume volume14
Issue issue1
Start Page 1
End Page 11
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002307373
JaLCDOI 10.18926/fest/12819
FullText URL 13_023_033.pdf
Author Zenihana, Tomohiro| Hisakane, Naoto| Morimoto, Tomoko| Ishikawa, Hirofumi|
Abstract We carried out simulations of various scenarios for bioterrorist attacks using smallpox occurring in a virtual area set up on the basis of the census of Okayama-city, Japan, which predict the effect of control strategies against bioterrorism and the loss scale. On simulating a smallpox epidemic, we followed the method of the Individual Based Model stochastically, which can treat the population in the virtual area as individuals. Individuals have personal information, behavior patterns, and interactions among social groups. We took into consideration the influence of residual immunity due to past vaccination. We considered Traced Vaccination (TV) and Mass Vaccination (MV) strategies against bioterrorism. We investigated the effect of TV and MV strategies on the suppression of smallpox epidemics. Consequently, the TV strategy was found to have higher effectiveness than the MV strategy.
Keywords smallpox bioterrorism Individual Based Model Traced Vaccination Mass Vaccination
Publication Title 岡山大学環境理工学部研究報告
Published Date 2008-03
Volume volume13
Issue issue1
Start Page 23
End Page 33
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002304844
JaLCDOI 10.18926/fest/12816
Title Alternative Statistical modeling for analysis of malaria epidemic behavior at Ishigaki Island
FullText URL 13_007_015.pdf
Author Ueki, Masao| Nakagawa, Yuuki| Fueda, Kaoru| Ishikawa, Hirofumi|
Abstract It is necessary to consider a stochastic variability in modeling malaria epidemic behavior since the malaria infection cycle essentially depends on stochastic elements. For this requirement, we need to construct an appropriate statistical model from available data in advance. In this report, we provide some statistical models for the analysis of malaria epidemic behavior at Ishigaki Island. These models can be used for recurrence of past malaria epidemic and prediction of future malaria epidemic at Ishigaki Island.
Keywords Anopheles minimus, generalized liner model Ishigaki Island malaria epidemic behavior prediction stochastic model
Publication Title 岡山大学環境理工学部研究報告
Published Date 2008-03
Volume volume13
Issue issue1
Start Page 7
End Page 15
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002304876
JaLCDOI 10.18926/fest/11610
FullText URL 001_047_053.pdf
Author Sasaki, Toru| Ishikawa, Hirofumi| Kajiwara, Tsuyoshi| Watanabe, Masaji|
Abstract We treat the problem of water pollution by the method of a mathematical model. We illustrate the method of analysis with Kojima Lake. We analyze in-flow and out-flow of the lake, compute numerical solutions of the governing equations of the water flow and the pollutant. The simulation leads to the conclusion concerning the figure of Kojima Lake.
Keywords Kojima lake Water analysis Finite element method
Publication Title 岡山大学環境理工学部研究報告
Published Date 1996-03
Volume volume1
Issue issue1
Start Page 47
End Page 53
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313787
JaLCDOI 10.18926/fest/11606
FullText URL 001_027_041.pdf
Author Ishikawa, Hirofumi|
Abstract The author has proved the dimension formula of the space of the Hilbert modular type cusp forms of weight two. We present further refinements of the dimension formula for a real quadratic number field Q(√D), and calculate it effectively. We tabulate the dimensions for square-free natural numbers D below 104 with the computer assistance. We also determine all the spaces of their dimension below 10.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1996-03
Volume volume1
Issue issue1
Start Page 27
End Page 41
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313526
JaLCDOI 10.18926/fest/11595
FullText URL 002_009_017.pdf
Author Ishikawa, Hirofumi|
Abstract In this paper, we have calculated the elliptic singularities of the symmetric Hilbert modular group defined over a real quadratic number field. Applying those to the dimension formula, we tabulate the dimensions of the space of symmetric Hilbert modular forms of weight two satisfying certain cusp condition.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1997-01-10
Volume volume2
Issue issue1
Start Page 9
End Page 17
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313960
JaLCDOI 10.18926/fest/11560
FullText URL 003_031_036.pdf
Author Sasaki, Toru| Kajiwara, Tsuyoshi| Ishikawa, Hirofumi|
Abstract We have computed the phase of spreading contaminations in Kojima Lake by using the upwind-type finite element method. We have treated the two cases: the pollutant flows from the Sasagase river and from the Kurashiki River. We see that the upwind-type finite element method is effective in both cases, when the diffusion constant is quite small.
Keywords Upwind-type Finite element method Kojima Lake
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 31
End Page 36
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313715
JaLCDOI 10.18926/fest/11554
FullText URL 003_005_009.pdf
Author Ishikawa, Hirofumi|
Abstract We investigate the Maass wave form for Γ(0)(2) whose eigenvalue of Laplacian Δ is 1/4-π(2)/log(2)(√2-1). In this note, we study the methods of calculation of its Fourier coefficients and carry out the numerical calculations.
Publication Title 岡山大学環境理工学部研究報告
Published Date 1998-01-14
Volume volume3
Issue issue1
Start Page 5
End Page 9
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313535
JaLCDOI 10.18926/fest/11548
FullText URL 005_001_006.pdf
Author Ishikawa, Hirofumi| Ishii, Akira| Kaneko, Akira|
Abstract We have estimated the degree of transmission of Plasmodium vivax malaria in Vanuatu Islands, eastern Melanesia with the aid of the computer simulations, which has been carried out on the platform of a mathematical transmission model. The malaria caused by Plasmodium vivax has a relapse character, which arises from hypnozoites in the liver. This phenomen makes a malaria control strategy difficult. When the mass drug administration is executed, the prevalence of Plasmodium vivax decreases moderately as compared with that of Plasmodium falciparum, and it recovers before long being affected by the relapses. The simulations suggest that one cannot attain the eradication of Plasmodium vivax malaria without the concentrated execution of the mass drug administration and the vector control that fairly reduces the vactorial capacity.
Keywords Plasmodium vivax computer simulation hypnozoite mass drug administration relapse
Publication Title 岡山大学環境理工学部研究報告
Published Date 2000-02-29
Volume volume5
Issue issue1
Start Page 1
End Page 6
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313438
JaLCDOI 10.18926/fest/11512
FullText URL 007_007_016.pdf
Author Ishii, Hiroyuki| Ishikawa, Hirofumi| Ohga, Yukio|
Abstract We have constructed a stochastic transmission model for lymphatic filariasis caused by Wuchereria bancrofti, and have analyzed its prevalence using computer simulations. In Pondicherry, India, where Wuchereria bancrofti has been spreading, the Vector Control Research Centre has carried out an integrated vector control strategy against malaria and filariasis for five years (1981~1985) with good results reported. Our study was aimed at evaluating the effect of vector control in the context of Pondicherry, and in particular the continuous effect for the post-control period. In this paper, we have used the LYMFASIM model proposed by Plaisier et al., the carrying capacity model by Rochet and the population dynamics model by us. In the LYMFASIM model and the carrying capacity model, we have modified the quantities of parameters in order to fit the models to the parasitological, entomological and epidemiological data in Pondicherry. We have combined the improved LYMFASIM model with the other models. Through simulations of our combinated model, we have compared the prevalence rate in the human population as well as the mean number of L3-larvae in the mosquito population, with and without vector control. As a result, the simulations show that the prevalence rate would be restrained for a long time even if only a small continuous effect of the vector control remains in the post-control period. However, the mean number of L3-larvae would recovered within a short time comparatively. This is because of the differences in life spans between human and mosquito as well as the incubation periods between the adult worm in the human host and L3-larvae in the mosquito vector.
Keywords Lymphatic filariasis mathematical model Pondicherry vector control Wuchereria bancrofti
Publication Title 岡山大学環境理工学部研究報告
Published Date 2002-03-22
Volume volume7
Issue issue1
Start Page 7
End Page 16
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313471
JaLCDOI 10.18926/fest/11510
FullText URL 007_001_005.pdf
Author Ohga, Yukio| Ishikawa, Hirofumi| Doi, Rikuo| Ishii, Hiroyuki|
Abstract In our study, we have investigated the influence of the intermediate host population density on the prevalence of Echinococcus multilocularis in the definitive host using a mathematical model of transmission. For the vole population (intermediate host) in Hokkaido, a model of population dynamics has been constructed in this paper which follows the seasonal and annual fluctuations. In the northeastern area, the vole density appears to fluctuate periodically with a 4 year cycle. The prevalence of Echinococcus multilocularis in the fox population (definitive host) can be affected by the density of vole through the fox ingesting infectious voles. Therefore we have prepared a food habit function of foxes and the logistic distribution has been proposed. The simulations which have been carried out using the mathematical model for transmission of Echinococcus multilocularis together with the vole dynamics have indicated that the prevalence in foxes is correlated and synchronized with the population dynamics of vole. In addition they have also made us recognize that it is necessary to introduce a suitable food habit function into the transmission model.
Keywords Echinococcus multilocularis food habit of foxes Hokkaido population dynamics vole
Publication Title 岡山大学環境理工学部研究報告
Published Date 2002-03-22
Volume volume7
Issue issue1
Start Page 1
End Page 5
ISSN 1341-9099
language 英語
File Version publisher
JaLCDOI 10.18926/fest/11487
FullText URL 008_001_007.pdf
Author Tsunekuni Yasuhiro| Ohga Yukio| Ishikawa, Hirofumi|
Abstract In 1990s, there were rapid increases in the number of HIV epidemics and AIDS cases in Thailand, Southeast Asia. In particular the risk of HIV infection was very high among female prostitutes who played a large part in the transmission of HIV infection. We formulated a mathematical model for the transmission of HIV in prostitutes. We carried out the model simulations to analyze the incipient spread of HIV infection and the effect of AIDS prevention methods in prostitutes. The simulation of our model indicates that even if the effect of AIDS prevention methods such as the recommendation of condom use for commercial sex workers would block the transmission at rate by 70%, the elimination of the HIV epidemic is still beyond attainment.
Keywords AIDS HIV prostitution Thailand transmission model
Publication Title 岡山大学環境理工学部研究報告
Published Date 2003-03
Volume volume8
Issue issue1
Start Page 1
End Page 7
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002314019