An accurate mathematical model predicting number of dengue cases in tropics

Dengue fever is a systemic viral infection of epidemic proportions in tropical countries. The incidence of dengue fever is ever increasing and has doubled over the last few decades. Estimated 50million new cases are detected each year and close to 10000 deaths occur each year. Epidemics are unpredictable and unprecedented. When epidemics occur, health services are over whelmed leading to overcrowding of hospitals. At present there is no evidence that dengue epidemics can be predicted. Since the breeding of the dengue mosquito is directly influenced by environmental factors, it is plausible that epidemics could be predicted using weather data. We hypothesized that there is a mathematical relationship between incidence of dengue fever and environmental factors and if such relationship exists, new cases of dengue fever in the succeeding months can be predicted using weather data of the current month. We developed a mathematical model using machine learning technique. We used Island wide dengue epidemiology data, weather data and population density in developing the model. We used incidence of dengue fever, average rain fall, humidity, wind speed, temperature and population density of each district in the model. We found that the model is able to predict the incidence of dengue fever of a given month in a given district with precision (RMSE between 18- 35.3). Further, using weather data of a given month, the number of cases of dengue in succeeding months too can be predicted with precision (RMSE 10.4—30). Health authorities can use existing weather data in predicting epidemics in the immediate future and therefore measures to prevent new cases can be taken and more importantly the authorities can prepare local authorities for outbreaks.

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Modelling the impact of delaying vaccination against SARS-CoV-2 assuming unlimited vaccine supply

Theoretical Biology and Medical Modelling ◽

10.1186/s12976-021-00143-0 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Marcos Amaku ◽

Dimas Tadeu Covas ◽

Francisco Antonio Bezerra Coutinho ◽

Raymundo Soares Azevedo ◽

Eduardo Massad

Keyword(s):

Mathematical Model ◽

Vaccination Campaign ◽

Vaccination Rate ◽

Sao Paulo ◽

The State ◽

São Paulo ◽

Health Authorities ◽

The World ◽

The Moment ◽

The Impact

Abstract Background At the moment we have more than 177 million cases and 3.8 million deaths (as of June 2021) around the world and vaccination represents the only hope to control the pandemic. Imperfections in planning vaccine acquisition and difficulties in implementing distribution among the population, however, have hampered the control of the virus so far. Methods We propose a new mathematical model to estimate the impact of vaccination delay against the 2019 coronavirus disease (COVID-19) on the number of cases and deaths due to the disease in Brazil. We apply the model to Brazil as a whole and to the State of Sao Paulo, the most affected by COVID-19 in Brazil. We simulated the model for the populations of the State of Sao Paulo and Brazil as a whole, varying the scenarios related to vaccine efficacy and compliance from the populations. Results The model projects that, in the absence of vaccination, almost 170 thousand deaths and more than 350 thousand deaths will occur by the end of 2021 for Sao Paulo and Brazil, respectively. If in contrast, Sao Paulo and Brazil had enough vaccine supply and so started a vaccination campaign in January with the maximum vaccination rate, compliance and efficacy, they could have averted more than 112 thousand deaths and 127 thousand deaths, respectively. In addition, for each month of delay the number of deaths increases monotonically in a logarithmic fashion, for both the State of Sao Paulo and Brazil as a whole. Conclusions Our model shows that the current delay in the vaccination schedules that is observed in many countries has serious consequences in terms of mortality by the disease and should serve as an alert to health authorities to speed the process up such that the highest number of people to be immunized is reached in the shortest period of time.

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Thermal Analysis of Expressway Considering Wind Effect

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.419.895 ◽

2013 ◽

Vol 419 ◽

pp. 895-904

Author(s):

X. Cao ◽

H. Miyashita ◽

T. Kako ◽

Z. Zhang ◽

B. Song

Keyword(s):

Mathematical Model ◽

Thermal Analysis ◽

Thermal Conduction ◽

Computer Calculation ◽

Basic Mechanism ◽

Weather Data ◽

Wind Effect ◽

Fortran Language ◽

Explicit Finite Difference ◽

Explicit Finite Difference Method

This paper reports a method of thermal analysis of expressway and the results of analysis of four expressways currently used in Japan. The authors built a mathematical model based on the principle of thermal conduction. For the boundary conditions in this mathematical model the influence of solar radiation, wind and air temperature etc. are taken into consideration. Explicit finite difference method is used in the analysis. The authors made an analysis program in Fortran language. Four main expressways distributing from the northern to the southern in Japan are chosen as the objects of this study. The observed weather data of the hottest days experienced by these expressways during the past 30 years is input into the computer calculation. The basic mechanism of expressway temperature change and effect factors are illuminated. The results are reported and discussed.

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Pengaruh Curah Hujan dan Debit Air Terhadap Produktivitas Energi Listrik yang Dihasilkan Pada Pembangkit Listrik Tenaga Air (Studi Kasus: Sub Unit PLTA Kracak, Kabupaten Bogor Jawa Barat)

Journal of Electrical Vocational Education and Technology ◽

10.21009/jevet.0051.09 ◽

2020 ◽

Vol 5 (1) ◽

pp. 56-60

Author(s):

Wildan Gunawan ◽

Suyitno Muslim ◽

Imam Arif Rahardjo

Keyword(s):

River Discharge ◽

Research Method ◽

Rainfall Intensity ◽

Discharge Rate ◽

Electrical Power ◽

Electric Energy ◽

Energy Productivity ◽

Rain Fall ◽

Average Rain

This research is aimed to understand the effects of rain fall and discharge rate towards hydro electric power plant productivity (case study at Kracak Sub Unit HPP, Bogor Regency Jawa Barat). Multiple regression tecnique analysis is used as research method with quantitative approach for describing the effects of rain fall and discharge rate towards hydro electric energy productivity. Based on Sub Unit PLTA Kracak during a highest down pour in June 2018 has gained electrical power about 173,583 kWh for 15,84 mm rain fall and the lowest rain fall in July 2018 is 0,86 mm only obtain 49,772 kWh electrical power with the average rain fall record in three stations is 8,9592 mm. Mean while, for the highest river discharge rate happened in February is 10,08 m3/detik which produce 198,296 kWh electrical power and the lowest in June that only gained 3,53 m3/detik which produce 49,772 kWh electrical power with the average of river discharge rate in 2018 is only 7,9858 m3/detik. The average of electrical power it self is only 156,0105 kWh for 8,9592 mm of rainfall and 7,9858 m3/detik river discharge rate record in 2018. The conclusion oh this research is the discharge rate in headwaters area is affected by rainfall intensity, but not necessarily affected to hydro electric energy productivity. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh curah hujan dan debit air terhadap produktivitas energi listrik yang dihasilkan pada pembangkit listrik tenaga air (Studi Kasus: Sub Unit PLTA Kracak, Kabupaten Bogor Jawa Barat). Metode yang digunakan dalam penelitian ini adalah metode deskriptif dengan pendekatan kuantitatif teknik analisis data regresi berganda untuk mendiskripsikan data penelitian curah hujan dan debit air terhadap produktivitas energi listrik yang dihasilkan. Berdasarkan data hasil penelitian yang diperoleh di Sub Unit PLTA Kracak data curah hujan tertinggi pada tahun 2018 di Bulan Juni sebesar 15,84 mm dapat menghasilkan energi listrik sebesar 173,593 kWh dan terendah di Bulan Juli sebesar 0,86 mm dapat menghasilkan energi listrik sebesar 49,772 kWh dengan rata-rata pertahun 2018 yaitu sebesar 8,9592 mm di tiga stasiun. Sedangkan data debit air pada tahun 2018 tertinggi di Bulan Februari sebesar 10,08 m3/detik dapat menghasilkan energi listrik sebesar 198,296 kWh dan terendah di Bulan Juli sebesar 3,53 m3/detik dapat menghasilkan energi listrik sebesar 49,772 dengan rata-rata pertahun 2018 debit air sebesar 7,9858 m3/detik. Dengan rata-rata curah hujan 8,9592 mm dan debit air 7,9858 m3/detik dapat menghasilkan energi listrik rata-rata pertahun 2018 sebesar 156,0105 kWh selama tahun 2018. Dapat disimpulkan curah hujan tidak berpengaruh langsung terhadap produktivitas energi listrik yang dihasilkan sedangkan debit air berpengaruh terhadap produktivitas energi listrik.

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Temperature and population density: interactional effects of environmental factors on phenotypic plasticity, immune defenses, and disease resistance in an insect pest

Ecology and Evolution ◽

10.1002/ece3.2158 ◽

2016 ◽

Vol 6 (11) ◽

pp. 3672-3683 ◽

Cited By ~ 7

Author(s):

Farley W. S. Silva ◽

Simon L. Elliot

Keyword(s):

Disease Resistance ◽

Phenotypic Plasticity ◽

Environmental Factors ◽

Population Density ◽

Insect Pest ◽

Immune Defenses

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Study on the Relationship between Population Density of Noctiluca scintillans and Environmental Factors in the Coastal Waters of Qinhuangdao

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1010-1012.635 ◽

2014 ◽

Vol 1010-1012 ◽

pp. 635-638

Author(s):

Yan Juan Xi ◽

Zhen Liang Zhao ◽

Chun Long Zhao ◽

Yan Qin Xi ◽

Li Yan ◽

...

Keyword(s):

Environmental Factors ◽

Population Density ◽

Correlation Analysis ◽

Dissolved Oxygen ◽

Linear Correlation ◽

Coastal Waters ◽

Ammonia Nitrogen ◽

Noctiluca Scintillans ◽

Nitrite Nitrate ◽

The Relationship

Based on the environmental survey data in off-shore of Qin Huangdao from May to June 2011,correlation analysis was made between population density of Noctiluca scintillans and environmental factors. The results indicates that population density of Noctiluca scintillans does not exist linear correlation with nitrite, nitrate, ammonia, nitrogen, phosphate,dissolved oxygen and PH ,it is positive correlation with temperature and silicate noctiluca and negatively correlation with transparency and salinity.

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Effects of environmental factors on Tigriopus fulvus, Fischer 1860, a Mediterranean harpacticoid copepod

Journal of Biological Research - Bollettino della Società Italiana di Biologia Sperimentale ◽

10.4081/jbr.2018.7113 ◽

2018 ◽

Vol 91 (1) ◽

Author(s):

Guido Bonello ◽

Cristiano Angelini ◽

Luigi Pane

Keyword(s):

Climate Change ◽

Life Cycle ◽

Environmental Factors ◽

Population Density ◽

Harpacticoid Copepod ◽

Environmental Parameters ◽

Chemical Parameters ◽

Climate Change Effects ◽

Physical Chemical ◽

Extinction Event

Tigriopus fulvus (Fischer, 1860) is a benthic harpacticoid copepod of the Mediterranean supralittoral zone. The transitional characteristics of this environment forced this species to develop high resistance to changes of environmental parameters. Nevertheless, Tigriopus fulvus life-cycle is influenced from the splashpools physical-chemical parameters. In this paper, we present the results of a supralittoral monitoring performed in 2014, confirming the influence of some of these environmental parameters on population buildups. Because of recent worldwide climate change effects, a threat might have been posed on this particularly exposed organism, whose population density decreased of a sixfold value in the last 30 years. During the three pools (A, B, C) monitoring, the maximum copepod density recorded was 1456 Ind/l (September 2014, Pool C), alongside first records of extinction event for Tigriopus fulvus.

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