LAboratory of Mathematical Parallel Systems

Lamps 2016 Symposium

    Speaker(s): 
    Modeling and dynamics of climate change and impact on vector-borne diseases
    York University
    Date: 
    Thursday, August 25, 2016 - 8:30am to 6:00pm
    Location: 
    280N York Lanes, York University
    Abstract: 

     

    Lamps Symposium

    Modeling and dynamics of climate change and impact on vector-borne diseases

    August 25, 2016

    280N York Lanes

     climate ontarioOntario

    The whole climate of the world has been changing regularly because of the increasing global warming by the natural means and human activities. By the research from Lamps climate modeling team, the annual mean temperature of Ontario has increased more than 1°C since 1900, and the decadal averages of both summer mean and maximum temperatures have been rising in general at Toronto too. All these changes have an enormous impact on the people’s lives and our ecosystems. Current evidence suggests that inter-annual and inter-decadal climate variability have a direct influence on the epidemiology of vector-borne diseases.  Vector-borne diseases are infections transmitted by the bite of infected arthropod species, such as mosquitoes and ticks. West Nile virus arrived in 2000 in Canada; the reported number of Lyme disease cases keeps increasing since 2009; Chikungunya and Zika virus may emerge to constitute a risk to Canadians. Vector-borne diseases are widespread in Canada.

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    Multiple factors impact the transmission of vector-borne diseases, including weather, habitat destruction, land use, pesticide application, and host density. Among them, weather factors influence survival and reproduction rates of vectors, in turn influencing habitat suitability, distribution and abundance; intensity and temporal-spatial pattern of vector activity (particularly biting rates) throughout the season; and rates of development, survival and reproduction of pathogens within vectors.

    Supported by Ontario Ministry of the Environment and Climate Change (MOECC), Lamps team has been working on climate change modeling studies for Ontario since 2009, a data portal was developed which serves as a platform for climate change impact and adaptation studies in Ontario. Supported by multiple resources including Canadian Institutes of Health Research (CIHR), Public Health Agency of Canada (PHAC), Environment Canada (EC) and NSERC, Lamps mosquito group and its network researchers have been working closely with Public Health administration and Health Units to study vector-borne diseases using surveillance data and modeling tools. Current research focuses on the distribution and density of vectors, transmission mechanisms and dynamics, developing forecasting tools to predict the vectors, virus risk and cases of human infection, assessing intervention programs.

     

    Organizers

                  Yiyuan Wang, Longbin Chen, Haitao Song and Huaiping Zhu

    Supported by

    cihrphac

    cfiontarionsercyorklamps

     

     

    The Schedule of the symposium

     

    Time                 

    Speaker

    Presentation

    08:30-08:40

    Opening remarks

    08:40-09:10

    Dr. John Liu

    Modelling the Dynamics of Regional Climate Change and Associated Impacts in Ontario

    09:10-9:40

    Peter Taylor

    Upper-level winds over southern Ontario: O-Q Net and NARR comparisons plus NARR analyses

    9:40-10:10

    Xin Qiu

    High Resolution Regional Climate Projections over Ontario

    10:10-10:30

    Ziwang Deng

    Ontario Climate Change Projection Web Data Portal

    10:30-10:50

    Health Break

    10:50-11:20

    Zhigui Lin

    The impact of climate warming and spatial heterogeneity on the spreading of the West Nile virus

    11:20-11:40

    Longbin Chen

    Dynamical modeling of West Nile virus transmission considering weather conditions

    11:40-12:00

    Don Yu

    Temperature-driven population abundance model for Culex pipiens and Culex restuans (Diptera: Culicidae)

    12:00-13:00

    Lunch

    13:00-13:20

    Wenzhe Li

    Temporal and Spatial Predictive Modeling of Mosquito Abundance and risk of human infection of West Nile virus in Greater Toronto Area

    13:20-13:40

    Yiyuan Wang

    The impact of weather and Stormwater Management Ponds on the transmission of West Nile virus

    13:40-14:10

    Sanyi Tang

    Dengue control: statistical and modeling analyses

    14:10-14:30

    Haitao Song   

    Is there a risk of Chikungunya transmission in Canada?

    14:30-14:50

    Yuehua Liu

    Projecting the Occurrence Probability of Zika Vector Ae. Albopictus Mosquito under the Changing Climate in Ontario, Canada

    14:50-15:10

    Xianghong Zhang

    Whether Wolbachia mosquito releasing can help to control dengue fever?

    15:10-15:30

    Health Break

    15:30-16:00

    Shibing You

    Standard-Unit-Epidemic-Disease (SUED) Evaluation Method for Empirical Research on Economic Losses

    16:00-16:20

     Philo, Juan Zhang

    Economic Assessment on Animal Epidemics Immunization Decisions- A Case Study of Asian Type I Foot and Mouth Disease

    16:20-16:50

    Yanni Xiao

    Modelling hospital infections in an intensive care unit

    16:50-17:20

    Zengji Du

    Solitary waves solutions of singularly perturbed higher-order KdV equation via geometric singular perturbation method

    17:20-17:40

    Ming Chen

    Effect of seasonal changing temperature on the growth of phytoplankton

    17:40-18:00

    Haixia Lu

    A Simplied Differential Equation Model for Hyphantria Cunea

    18:00-18:20

    Bo Yu

    Study on the Influencing Factors of the Quality of Internal Control Information Disclosure from Pharmaceutical Manufacturing Industry in China2013-2015

    18:20-18:40

    Xiaojie Lin

     Periodic solution to a multispecies predator-prey dynamic system with Beddington-DeAngelis functional response  

     

     

    Titles and abstracts

    Title: Modelling the Dynamics of Regional Climate Change and Associated Impacts in Ontario

    Speaker: Dr. John Liu

                    Ministry of the Environment and Climate Change, Ontario

    Abstract: Due to their coarse resolution, global climate models (GCMs) are unable to resolve local geophysical features at regional/local scales, such as the Great Lakes and the Niagara Escarpment which have significant impacts on Ontario’s local climate. On the other hand, most adaptation planning is at local/community scales and need climate information at higher resolution. To address this climate information gap, Ontario Government has invested in the past decade to refine the climate information from the global scale (i.e. 100’s kilometers) down to local scales (i.e. 10’s kilometers) using state-of-the-science downscaling techniques. These downscaled climate data were made publicly available for free to practitioners. To support the implementation of the Ontario Climate Change Strategy and Action Plan, the Government has also funded projects on climate change impact assessments This talk will provide a n up-to-date overview on Ontario-specific high resolution regional climate modelling and impact assessments in support of adaptation/mitigation.

    Title: Upper-level winds over southern Ontario: O-Q Net and NARR comparisons plus NARR analyses

    Speaker: Peter Taylor

                    Department of Earth and Space, Science and Engineering, York University

    Abstract: The IPCC (2013) report discusses upper level winds and states, "In contrast to surface winds, winds above the planetary boundary layer have received little attention in AR4 (IPCC, 2007)." It goes on to state, "In the past few years, interest in an accurate depiction of upper air winds has grown, as they are essential for estimating the state and changes of the general atmospheric circulation and for explaining changes in the surface winds."

    Upper-level winds are primarily measured by tracking the position of radiosonde balloons as they rise through the atmosphere. Radiosondes are released from a global network at nominal times of 0000 UTC and 1200 UTC each day and data are quickly available to the world's weather services, and to the public. The network is relatively coarse, spatially, and soundings are normally only two per day.  In an endeavour to provide better spatial and temporal upper-level regional wind measurements a network of VHF wind profilers, the O-Q Net, has been installed and operated by York, Western and McGill Universities and with support from Mardoc Inc and Environment Canada.

    We have made comparisons between winds measured by the O-Q Net profilers and the winds reported by NARR (NCEP North American Regional Reanalysis) analyses. There is good agreement which provides support for the use of NARR data to investigate longer term variations in upper level winds associated with climate change for this region (southern Ontario).

    Analyses of upper air winds from NARR data for southern Ontario for the past 35 years are presented. Annual averages show a slight weakening of 500 hPa zonal wind and a slight increase in the mean of the absolute value of the Meridional Circulation Index (|MCI|). These trends are expected as a result of Arctic Amplification of tropospheric temperature increases but are weak in comparison to inter-annual variability. There are seasonal variations in monthly averaged wind speed and April and October maxima in monthly averaged |MCI|.

    Links between upper level zonal winds and |MCI| and surface temperatures and precipitation are complicated by seasonal variations. Annual averaged values are virtually uncorrelated. Monthly perturbations show stronger correlation on average but annual averages of monthly perturbation correlations have large variability. The NARR, and other reanalysis data sets are a valuable resource for studies of climate change on time scales of several decades. More research on the relationships between upper level winds and surface climate (winds, temperature and precipitation) may lead to useful indications of potential future changes of concern for agriculture and forestry.

    Title: High Resolution Regional Climate Projections over Ontario

    Speaker: Xin Qiu

                    Novus Environmental Inc. and York University

    Abstract: High Resolution Regional Climate Projections over Ontario Using State-of-Science Combined Downscaling with a Large Ensemble of Global and Regional Climate Model Results. The method combines the Ensemble Optimal Interpolation (ENOI) and the Local Intensity Scaling (LOCI) techniques. The third generation high resolution (~0.312 degree) reanalysis product NCEP CFSR (Climate Forecast System Reanalysis) was used to construct the spatially and temporally varying background error matrix of the ENOI and rescaling factors of LOCI. Station observation, CRU (Climate Research Unit) and ECWMF (European Center for Medium Range Weather Forecasts) reanalysis products were used to validate the downscaling model. Results demonstrated that the downscaling products simulated mean climate condition very well. More importantly, the downscaling products can also well replicate many widely used climate extreme indices. The downscaling products have been hosted at the Ontario Climate Change Portal at (http://occp.lamps.yorku.ca) to provide easy and free access to various users.

    Title: Ontario Climate Change Projection Web Data Portal

    Speaker: Ziwang Deng

                    LAMPS, Department of Mathematics and Statistics, York University

    Abstract: Decisions related to climate change are complex, costly and have long-term implications. It is therefore vital that such decisions are based on the best available climate dataset. For governments, enterprises and common public need high resolution climate data (historical and projection) when they make policy and decisions for climate mitigation and adaptation. To meet the requirements of stakeholders on climate change in Ontario, we developed a web data portal (yorku.ca/occp) using advanced web application development techniques. The portal provides high resolution climate data, figures, maps, videos, factsheets and special analysis results for public to download. Our datasets and results have been used by Ontario government departments and other various user. This web data portal include six components, the interactive mapping, data downloading, climate change videos, pictures, analysis results for special topics and climate change indicator calculation tools. This web data portal development is an on-going project; it will be continually improved as more data available.   

     

    Title: The impact of climate warming and spatial heterogeneity on the spreading of the West Nile virus

    Speaker: Zhigui Lin

                    Yangzhou University

    Abstract: This talk deals with mathematical models describing the dynamic of West Nile virus in North America. For the spatially-independent WNv model, the usual basic reproduction number $R_0$ is given and for the diffusive WNv model in a bounded domain, the basic reproduction numbers $R_0^N, R_0^D$ are defined. To model and explore the expanding front of the infective region, a reaction-diffusion problem with free boundaries is proposed. The spatial-temporal risk index $R_0^F(t)$, which involves regional characteristic and time, is defined. Sufficient conditions for the virus to vanish or spread are given. Our results suggest that the spreading or vanishing of the virus depends on the initial number of infected individuals, the area of the infected region, the diffusion rate, and other factors. Some remarks on the basic reproduction numbers and the spreading speeds are presented and compared. Moreover, we establish a new WNv model to describe the impart of climate warming and spatial heterogeneity. This is a joint work with Huaiping Zhu.

    Title: Dynamical modeling of West Nile virus transmission considering weather conditions

    Speaker: Longbin Chen

                    LAMPS, Department of Mathematics and Statistics, York University

    Abstract: Weather conditions (temperature and precipitation) can affect the abundance and the behavior of vector mosquitoes for West Nile virus. In this study, we incorporate both temperature and precipitation in a compartmental model for West Nile virus transmission between birds, mosquitoes, and humans. We numerically simulate and explore how weather conditions affect the virus transmission by using a statistical model with temperature and precipitation as explanatory variables for the total number of mosquitoes based on surveillance and weather data from Peel Region, Ontario. We present simulation results under different weather patterns to understand the complex dynamics of West Nile virus transmission and test the proposed model.  The dynamical models can be used towards the real-time forecasting of the risk of West Nile virus. This is a work supervised by Professor Huaiping Zhu and Professor Steven Wang.

    Title: Temperature-driven population abundance model for Culex pipiens and Culex restuans (Diptera: Culicidae)

    Speaker: Don Yu

                      LAMPS, Department of Mathematics and Statistics, York University

    Abstract: Vector-borne diseases account for more than 17% of all infectious diseases worldwide and cause more than 1 million deaths annually. Understanding the relationship between environmental factors and their influence on vector biology is imperative in the fight against vector-borne diseases such as dengue, malaria, zika, and West Nile virus. We develop a temperature-driven abundance model for West Nile vector species Culex pipiens and Culex restuans. Temperature dependent response functions for mosquito development, mortality, and diapause were formulated based on results from published field and laboratory studies. Results of model simulations compared to observed mosquito traps counts from 2004-2015 demonstrate the capacity of our model to predict the observed trend of the mosquito population in the Peel Region of southern Ontario over a single season. The proposed model has potential to be used as a real-time mosquito abundance forecasting tool and would have direct application in mosquito control programs.  This is work is supported by CIHR, PHAC, and NSERC, under the supervision of Professors Neal Madras and Huaiping Zhu.

    Title: Temporal and Spatial Predictive Modeling of Mosquito Abundance and risk of human infection of West Nile virus in Greater Toronto Area

    Speaker: Wenzhe Li

                    LAMPS, Department of Mathematics and Statistics, York University

    Abstract: Emerging and re-emerging vector-borne infectious diseases have drawn greater attentions in recent years worldwide, e.g. West Nile virus (WNv),  dengue fever and Zika virus. Abundance of culex mosquitoes, the vector of WNv, is sensitive to both weather conditions and landscape. In this study, we establish predictive models for mosquito abundance and risk of WNv with all of these factors. Using the surveillance data from regions of Greater Toronto Area (GTA), we first define local modeling regions with the census tracts as units for each region, then the predictive models are built on these modeling units for the forecasting of culex mosquito abundance and risk of human infection of WNv in GTA.  This is a work under the supervision of Dr. Beate Sander and Dr. Huaiping Zhu.

    Title: The impact of weather and Stormwater Management Ponds on the transmission of West Nile virus

    Speaker: Yiyuan Wang

                    LAMPS, Department of Mathematics and Statistics, York University

    Abstract: By investigating the data from larvae surveillance program launched by Toronto and Region Conservation Authority (TRCA), we establish a dynamical model to study the impact of weather and Stormwater Management Ponds (SWMP) on the mosquito abundance and the transmission of West Nile virus (WNv). The results show that moderate temperature, rainfall and the weaker aquatic intraspecific competition in the SWMP will increase the basic reproduction number, consequently the higher risk of WNv. This is a joint work with Wendy Pons, Jessica Feng and Huaiping Zhu.

    Title: Dengue control: statistical and modeling analyses

    Speaker: Sanyi Tang

                    School of Mathematics and Information Sciences, Shaanxi Normal University

    Abstract: In this talk, our recently works concerning the dengue disease control will be introduced and discussed. In particular, what we have done on this topic and what we aim to go further will be introduced in more detail. Moreover, we would also like to introduce the data sets, main methods and results obtained in those works.

    Title:  Is there a risk of Chikungunya transmission in Canada?

    Speaker: Haitao Song

                    LAMPS, York University and CSRC, Shanxi University

    Abstract: Chikungunya is a mosquito-borne disease which is transmitted by Aedes mosquitoes. Mosquitoes play an important role in the Chikungunya transmission. To investigate the risk of Chikungunya in Canada, we formulated a delay differential equation model with maturation delay, extrinsic incubation delay and intrinsic incubation delay. Dynamical analysis shows that maturation delay may destabilize the infected steady state by leading to Hopf bifurcation and stable periodic oscillations. From theory analysis and numerical simulations, we can know that extrinsic incubation delay and intrinsic incubation delay do not affect the stability of the infected steady state. Maturation period, intrinsic incubation period and extrinsic incubation period are used to estimate the risk of Chikungunya transmission in Canada. This is a joint work with Min Weng, Nick Ogden and Haiping Zhu.

    Title: Projecting the Occurrence Probability of Zika Vector Ae. Albopictus Mosquito under the Changing Climate in Ontario, Canada

    Speaker: Yuehua Liu, 

                    University of Toronto

    Abstract: This study was motivated by the recent outbreaks of Zika virus in its source regions and it appears spreading into other regions. The observed cases in the United States have increased since 2015, with the most recent outbreaks in the Miami areas. It is well-known that weather/climate variations affect mosquito populations, including the Zika vector Ae. Albopictus (AA). Considering the changing climate, it is very natural to ask when this Zika carrying species will arrive to us. However, in addition to weather/climate, other factors like human being travelling pattern can also contribute to the answer to this question. In fact, human being traveling is the current major factor for the reported infection cases in Canada. While globalization promotes the travelling frequency among countries, accurate projections of travelling pattern and frequency are very challenging at this moment. The primary objective of this pioneering study is to explore how future changing climate could impact the AA occurrence probability in Ontario, Canada. A new ensemble of models for AA occurrence probability was developed with the Boosted Regression Trees (BRT) package in R, historical climate, vegetation indices and AA occurrence data. Then the ensemble model was used to project the AA occurrence probability for two future time periods, 2050s (2041–2060) and 2070s (2061–2080). Results from this study demonstrate potential northward spatial expansion of AA occurrence across Ontario as a result of climate change, especially under those warm scenarios. This implies potentially increased risks of Zika virus and more intensive mosquito monitoring and controlling measures would be needed in Ontario considering future climate change. This is a work under the supervision of Dr. Jing Chen and Huaiping Zhu.

    Title: Whether Wolbachia mosquito releasing can help to control dengue fever?

    Speaker: Xianghong Zhang 

                    Lamps and Shaanxi Normal University

    Abstract: With more than one-third of the world’s population living in areas at risk for infection, dengue virus is a leading cause of illness and death in the tropics and subtropics.  According to USA CDC, as many as 400 million people are infected yearly. Dengue is transmitted to humans by mosquitoes. To control the spread of dengue, some countries, such as Australia, Brazil, Vietnam etc. are releasing Wolbachiamosquitoes in hope to control the mosquito density to reduce the risk of human infection. In 2015, China started the experiment to release the Wolbachiamosquitoes in selected isolated area in Guangzhou, the city experienced the largest outbreak of dengue in 2014.  But the question remains: Wether Wolbachiamosquito releasing help to control the transmission of dengue fever?  In this talk, I will introduce our primary modeling studies of mosquito augmentation, incorporating the effects of cytoplasmic incompatibility, mosquito releases with sex to investigate whether the strategies of population suppression and replacement can be realized for dengue control.

    Title: Standard-Unit-Epidemic-Disease (SUED) Evaluation Method for Empirical Research on Economic Losses

    Speaker: Shibing You

                    Economics and Management School, Wuhan University

    Abstract: Animal epidemics threaten economic development, the balance of ecological environments and public health. We proposes an innovative loss evaluation method called Standard-Unit-Epidemic-Disease (SUED), it can rapidly assess the probable losses arising from an animal epidemic in a region even if the related data are incomplete, and provide a basis for decision makers to propose appropriate actions. We establishes a methodology for a loss evaluation system for an area on an economic, social and environmental basis, which defines the standard evaluation index system of the area. Subsequently, the entropy method is introduced to study the epidemic effects on the area to be evaluated and “disease degree coefficient” (DDC) is introduced to adjust the evaluation of the loss. A case study is presented with data from Shandong Province (standard area) and Chifeng City (the area to be evaluated). This method offers a rigorous methodology and useful reference for evaluating the losses cialisfrance24.com resulting from animal epidemics and other disasters.

    Title: Economic Assessment on Animal Epidemics Immunization Decisions- A Case Study of Asian Type I Foot and Mouth Disease

    Speaker: Philo Juan Zhang

                    Shanxi University

    Abstract: The economic benefits of Government intervention in economic animal disease control has been widely affirmed. There are different measures in animal disease prevention and control. In various stages, selection of control measures will be very different in different countries. Economic assessment on animal epidemics immunization decisions is a theory which is taken from the angle of economics to analysis the decision of keeping or quiting compulsory immunization against animal epidemics. The animal disease economic loss evaluation theory and the dynamic model is applied on Chinese type I foot and mouth disease immune decision-making empirical research, and the costs of keeping compulsory immunization and exsiting immunization are both measured based on the correlations between the loss value and foci, and the prediction of outbreak number during 2017-2020. At last, the smaller total economic cost control strategy could be determined under the two different risk costs, then the recommendable policy suggestion of keeping compulsory immunization or exiting immunization was proposed. It provides a research paradigm for the risk decision-making of government.

    Title: Modelling hospital infections in an intensive care unit

    Speaker: Yanni Xiao

                    Department of Applied Mathematics, Xi’an Jiaotong University

    Abstract: Major challenges remain when attempting to quantify and evaluate the impacts of contaminated environments and heterogeneity in the cohorting of health care workers (HCWs) on hospital infections. Data on the detection rate of multidrug-resistant Acinetobacter baumannii (MRAB) and Methicillin-resistant Staphylococcus aureus (MRSA) in a Chinese intensive care unit (ICU) were obtained to accurately evaluate the level of environmental contamination and also to simplify existing models. In this talk, a data-driven mathematical models, including mean-field and pair approximation models (deterministic and stochastic), were proposed to examine the comprehensive effect of integrated measures including cohorting, increasing nurse-patient ratios and improvement of environmental sanitation on MRAB/MRSA infection. Our results indicate that for clean environments and with strict cohorting, increasing the nurse-patient ratio results in an initial increase and then a decline in MRAB/ MRSA colonization. In contrast, in contaminated environments, increasing the nurse-patient ratio may lead to either a consistent increase or an initial increase followed by a decline of MRAB colonization, depending on the level of environmental contamination and the cohorting rate. In order to develop more effective control strategies, the findings suggest that increasing the cohorting rate and nurse-patient ratio are effective interventions for relatively clean environments, while cleaning the environment more frequently and increasing hand washing rate are suitable measures in contaminated environments.

    Joint work with X.Wang, J.Wang, X. Lu, Yong Chen and Li Han.

    Title: Solitary waves solutions of singularly perturbed higher-order KdV equation via geometric singular perturbation method

    Speaker: Zengji Du

                    School of Mathematics and Statistics, Jiangsu Normal University

    Abstract: In this paper, we are concerned with a multispecies competitive predator-prey dynamic system with Beddington-DeAngelis functional response. Some sufficient conditions which guarantee the existence of positive periodic solution for the model are obtained by applying the Mawhin coincidence theory. The global asymptotic stability of periodic solutions for this system is also obtained. 

    Title: Effect of seasonal changing temperature on the growth of phytoplankton

    Speaker: Ming Chen

                    LAMPS and Northeast Normal University

    Abstract: In this talk, I will present an non-autonomous nutrient-phytoplankton interacting model to study the effect of daily changing temperature. The impacts of temperature on metabolism of phytoplankton such as nutrient uptake, death rate, and nutrient releasing from particulate nutrient are investigated. The ecological reproductive index is formulated to present a threshold criteria and to characterize the dynamics of phytoplankton. The existence and stability of boundary and positive periodic solution are established by the coincidence degree theory and Lyapunov direct method. The effect of seasonal temperature and daily temperature on phytoplankton biomass are simulated numerically. Numerical simulation shows that the phytoplankton biomass is very robust to the variation of water temperature. The performance and the adaptability of the model is well assessed by carrying out an application scenario to our field study in Lake Tai in China. The dynamics of the model and model predictions agree well with the experimental data. Our model provides a reasonable explanation of triggering mechanism of phytoplankton bloom. This is a joint work with Meng Fan and Huaiping Zhu.

    Title: A Simplied Differential Equation Model for Hyphantria Cunea

    Speaker: Haixia Lu

                    LAMPS and Suqian College, China

    Abstract:  Hyphantria cunea (Drury) commonly called fall webworm, is a kind of defoliator native to North America. This species has become an invasive pest throughout Europe and Asia, it has been rapidly spreading and caused great economic losses. It is listed as one of the worldwide quarantine pests. H.cunea has a bivoltine or trivoltine life cycle. The complete metamorphosis of the H.cunea goes through four distinct stages of development, namely egg, larva, pupa and adult H.cunea stage, some stages depend on weather conditions of the year.  Understanding the population dynamics of H.cunea and the relationship between H.cunea and the environment, is fundamental to device effective and realistic methods to control H.cunea population. In this talk, I will present a simple dynamical model to study the impact of weather conditions on the reproduction and development of H. cunea.  This is a joint work with Amy Wu and Huaiping Zhu.

    Title: Study on the Influencing Factors of the Quality of Internal Control Information Disclosure from Pharmaceutical Manufacturing Industry in China2013-2015

    Speaker: Bo Yu

                    School of Economics and Management,

                    Nanjing University of Information Science and Technology

    Abstract:  The quality of information disclosure of the internal control becomes the focus by social people from all walks of life for the domestic and foreign financial frauds emerge in endlessly. The company's internal control information disclosure is an important form of non-financial information disclosure, which can promote the internal construction of companies, protect the interests of investors, improve the transparency of capitalist market, and make the resource allocation efficiency. Related with human life and health, pharmaceutical manufacturing industry is focused by the market, especially internal control information disclosure. The recent poison vaccine event gives us an alarm bell. However, which factors influence the quality of internal control information disclosure? This paper selects internal control information disclosure of listed companies in pharmaceutical manufacturing from 2013 to 2015 as sample, analyzes their disclosure situation and influencing factors, and puts forward some improved suggestion. This work is under the supervision of Professor Huaiping Zhu.

    Title: Periodic solution to a multispecies predator-prey dynamic system with Beddington-DeAngelis functional response  

    Speaker: Xiaojie Lin

                   School of Mathematics and Statistics, Jiangsu Normal University

    Abstract:  In this talk, we are concerned with a multispecies competitive predator-prey dynamic system with Beddington-DeAngelis functional response. Some sufficient conditions which guarantee the existence of positive periodic solution for the model are obtained by applying the Mawhin coincidence theory. The global asymptotic stability of periodic solutions for this system is also obtained.

    Speakers:

     

    Dr. John Liu, Ministry of the Environment and Climate Change (MOECC)

    Peter Taylor, Peter Taylor, Lassonde School of Engineering, York University

    Qiu Xin, Novus Environmental Inc. and Lamps York University

    Ziwang Deng, Lamps, York University

    Zhigui Lin, Yangzhou University, China

    Longbin Chen, Lamps, York University

    Don Yu, Lamps, York University

    Wenzhe Li, Lamps, York University

    Yiyuan Wang, Lamps, York University

    Sanyi Tang, Shaanxi Normal University, China

    Haitao Song, LAMPS, York University and CSRC, Shanxi University, China

    Yuehua Liu, University of Toronto

    Xianghong Zhang, Lamps and Shaanxi Normal University, China

    Shibing You, Wuhan University, China

    Philo, Juan Zhang, Shanxi University

    Yanni Xiao, Xi’an Jiaotong University, China

    Zengji Du, Jiangsu Normal University, China

    Ming Chen, LAMPS and Northeast Normal University, China

    Haixia Lu, LAMPS and Suqian College, China

    Bo Yu, Nanjing University of Information Science and Technology, China

    Xiaojie Lin,  Jiangsu Normal University, China

    Huaiping Zhu, Lamps, York University