The Effects of Different Deployment Strategies of Artemisinin Combination Therapies on Slowing Down the Spread of Antimalarial Drug Resistence: Investigation With Individual-Based Simulations

Despite the success of recent global malaria control efforts, which have halved global malaria mortality since 2000, malaria is still one of the world’s most deadly diseases causing an estimated half a million deaths, mostly among African children, and around a quarter of billion clinical episodes every year as reported in 2014. Drug resistance is one of the most important challenges to malaria elimination. To contain drug resistance, many efforts have been put forth including improvement of surveillance systems and mass treatment in order to stop or slow down the transmission of the resistant strain. To find out whether a population-level treatment strategy can have any benefit in containing drug resistance, mathematical models are an appropriate approach to this problem and individual-based models allow us to have a better understanding of the effect of individual heterogeneities on the outcome. The first part of the thesis is about building and validating an individual based microsimulation. The model is implemented as an individual-based discrete-time event simulation model in C++. The behaviors and the state changes of human individuals are determined by relevant events and mathematical formulas. This integrated model combines components that reproduce the most important features of malaria transmission and epidemiology: the infectiousness of human populations; clinical model of acute illness; heterogeneities in individuals’ age, biting-rate level, drug absorption, drug action, multiple parasite populations, and human immunity. To validate this individual-based model, two types of validation have been done. The model’s parameters were obtained from field or clinical data were used directly in the model. For those parameters that cannot be obtained directly from literature review, sensitivity analysis has been done to find how variation in parameter values affects certain key features of malaria epidemiology. The second part of the thesis focused on the comparison between population-scaled treatment strategies. The results showed that using multiple first-line therapies (MFT) results in a lower number of treatment failures compared to other strategies where a single first-line ACT is recommended. This result is robust to various epidemiological, pharmacological, and evolutionary features of malaria transmission. In addition, including non-ACT therapy in an MFT strategy seems to have a significant benefit in reducing the pressure on artemisinin-resistance evolution, delaying its emergence and slowing its spread. The third part of the thesis focused on individual-level treatment strategies to combat artemisinin resistance. The results showed that lengthening an ACT course or using multiple courses of ACT can reduce the long-term number of treatment failures significantly. The work reported here introduces a novel individual-based simulation that includes drug resistance evolution and the ability to be scaled up to millions number of individuals. The challenge that remains is to evaluate the feasibility of these novel treatment strategies given that they will need to be implemented in the real world of malaria control programs, their operations, human behavior, and economic realities

Effects of Fertilizers on Biomass, Sugar Content and Ethanol Production of Sweet Sorghum

Sweet sorghum (Sorghum bicolor) is a promising alternative crop for bioethanol production in developing countries. However, to extend the cultivative area of this crop, it needs to develop an appropriate growing protocol for farmers. This chapter describes the examination of different doses of fertilizers combined with manure and micronutrients, in various applied times, on biomass, sugar content and ethanol production of sweet sorghum. It was observed that the application of 90 N + 90 P2O5 + 60 K2O provided maximum stem yield and optimum contents of sugar and ethanol yield, however nontreatment of any among P, P2O5 and K2O caused significant reduction of biomass and ethanol production. Higher fertilization >90 N may provide greater productivity of this crop but it may cause lodging and economic deficit for farmers in developing countries. It was also found that the applied times of fertilization should be at 3–4 to 7–8 leaf stage. In contrast, when the fertilization was as close to the flowering stage caused remarkable reduction of stem yield and ethanol production. The supplementation of (NH4)2MO7O2.4H2O at 5 kg/ha provided an increase of 10–12 tons/ha of stem yield and a remarkable enrichment of ethanol production. Findings of this study are useful for farmers and agricultural extensionists to promote biomass and ethanol productivity of this crop for bioethanol production. This research also highlights a greater possibility of exploiting sweet sorghum cultivation in infertile and hilly, abandoned areas for ethanol production

Methanol extract from Vietnamese Caesalpinia sappan induces apoptosis in HeLa cells

BACKGROUND: This study evaluated the cytotoxic activity of extracts from Caesalpinia sappan heartwood against multiple cancer cell lines using an MTT cell viability assay. The cell death though induction of apoptosis was as indicated by DNA fragmentation and caspase-3 enzyme activation. RESULTS: A methanol extract from C. sappan (MECS) showed cytotoxic activity against several of the cancer cell lines. The most potent activity exhibited by the MECS was against HeLa cells with an IC50value of 26.5 ± 3.2 µg/mL. Treatment of HeLa cells with various MECS concentrations resulted in growth inhibition and induction of apoptosis, as indicated by DNA fragmentation and caspase-3 enzyme activation. CONCLUSION: This study is the first report of the anticancer properties of the heartwood of C. sappan native to Vietnam. Our findings demonstrate that C. sappan heartwood may have beneficial applications in the field of anticancer drug discovery

Cooperative Group In Current Vietnamese Commercial Environment

Purpose: The article researches the compatibility between the cooperative group and the current commercial environment in Vietnam to propose for improvement to the laws and for promotion of development of the cooperative group.   Theoretical framework: Recent literature points out that the cooperative group model is quite suitable for the production and business psychology of citizens in Vietnam. In the current stage of development, however, from the influence and impact of international integration and the increasingly fierce competitive pressure of various types of enterprises, the cooperative group have encountered many difficulties to survive. On the other hand, in the context of judicial reform in Vietnam, the issue of complete law system and expanding the freedom to business has always been paid special attention by the Party and Vietnam State.   Design/methodology/approach: The authors have combined traditional research methods of legal science such as legal analysis method, legal efficiency assessment method and legal comparison method.   Findings: According to research, the cooperative group is well adapted to Vietnam's commercial environment because it is compatible with investor psychology and meets the conditions and circumstances of nature, economy and society. However, since Vietnam's deep integration with the rest of the world, the cooperative group model has faced numerous difficulties and challenges, and if suitable solutions are not found, it is very likely that this collective economy will become increasingly difficult. As a result, the article suggests some important solutions, such as offering cooperative group legal status and requiring more preferential lending policies with long loan terms, simple and quick loan procedures, and easy team cooperation.   Research, Practical & Social implications: This research may support many develop future research in Vietnam.   Originality/value: The study of the freedom to business become more and more urgent and very important in Vietnam

CHARACTERISTICS OF QUATERNARY SEDIMENTARY FACIES IN RELATION TO WATER BEARING CAPACITY OF AQUIFERS AND AQUICLUDES IN RED RIVER DELTA, VIETNAM

Joint Research on Environmental Science and Technology for the Eart