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Abstract Dengue is expanding globally, but how dengue emergence is shaped locally by interactions between climatic and socio-environmental factors is not well understood. Here, we investigate the drivers of dengue incidence and emergence in Vietnam, through analysing 23 years of district-level case data spanning a period of significant socioeconomic change (1998-2020). We show that urban infrastructure factors (sanitation, water supply, long-term urban growth) predict local spatial patterns of dengue incidence, while human mobility is a more influential driver in subtropical northern regions than the endemic south. Temperature is the dominant factor shaping dengue’s distribution and dynamics, and using long-term reanalysis temperature data we show that warming since 1950 has expanded transmission risk throughout Vietnam, and most strongly in current dengue emergence hotspots (e.g., southern central regions, Ha Noi). In contrast, effects of hydrometeorology are complex, multi-scalar and dependent on local context: risk increases under either short-term precipitation excess or long-term drought, but improvements in water supply mitigate drought-associated risks except under extreme conditions. Our findings challenge the assumption that dengue is an urban disease, instead suggesting that incidence peaks in transitional landscapes with intermediate infrastructure provision, and provide evidence that interactions between recent climate change and mobility are contributing to dengue’s expansion throughout Vietnam.

Background: The protective or pathogenic role of T lymphocytes during the acute phase of dengue virus (DENV) infection has not been fully understood despite its importance in immunity and vaccine development.Objectives: This study aimed to clarify the kinetics of T lymphocyte subsets during the clinical course of acute dengue patients.Study design: In this hospital-based cohort study, 59 eligible Vietnamese dengue patients were recruited and admitted. They were investigated and monitored for T cell subsets and a panel of clinical and laboratory parameters every day until discharged and at post-discharge from the hospital.Results: We described for the first time the kinetics of T cell response during the clinical course of DENV infection. Severe cases showed significantly lower levels of effector CD8+ T cells compared to mild cases at day −1 (p = 0.017) and day 0 (p = 0.033) of defervescence. After defervescence, these cell counts in severe cases increased rapidly to equalize with the levels of mild cases. Our results also showed a decline in total CD4+ T, Th1, Th1/17 cells during febrile phase of dengue patients compared to normal controls or convalescent phase. On the other hand, Th2 cells increased during DENV infection until convalescent phase. Cytokines such as interferon-γ, IL-12p70, IL-5, IL-23, IL-17A showed tendency to decrease on day 0 and 1 compared with convalescence and only IL-5 showed significance indicating the production during acute phase was not systemic.Conclusion: With a rigorous study design, we uncovered the kinetics of T cells in natural DENV infection. Decreased number of effector CD8+ T cells in the early phase of infection and subsequent increment after defervescence day probably associated with the T cell migration in DENV infection.

In this paper, a time step integration method for resolving the differential equation of motion of discrete structures subjected to dynamic loads is presented. This method is derived based on the approximation of acceleration in two time steps by a combination of both trigonometric cosine and hyperbolic cosine functions with weighted coefficient. The necessary formula of the present method is elaborated for integrating of the governing equation of motion in structural dynamics. The accuracy and stability of the present method are also studied. The numerical results are compared with those obtained using Newmark method, linear acceleration method, showing high effectiveness of the new method.

Mục tiêu của nghiên cứu là phân tích tần số dao động riêng của hệ thanh không gian bằng phương pháp độ cứng động lực. Nghiên cứu trình bày cách xây dựng các ma trận độ cứng động lực của phần tử thanh thẳng chịu lực dọc trục, chịu xoắn và chịu uốn trên cơ sở tìm nghiệm chính xác của phương trình cân bằng động học theo lý thuyết dầm Euler – Bernoulli. Từ đó, các ma trận trên được sử dụng để xây dựng ma trận độ cứng động lực cho phần tử thanh chịu lực tổng quát và ứng dụng nó vào việc phân tích tần số dao động riêng của hệ thanh không gian. So sánh các kết quả tính toán của phương pháp độ cứng động lực với các kết quả của phương pháp phần tử hữu hạn cho thấy độ chính xác của phương pháp độ cứng động lực. Phương pháp độ cứng động lực cho kết quả phân tích chính xác ngay khi xem thanh là một phần tử duy nhất – điều mà phương pháp phần tử hữu hạn không làm được.

An abstract of the paper on the agents of sever acute respiratory infection presented during the Institut Pasteur International Network Annual Scientific Meeting at Hong Kong, China, from November 22-23, 2010 is presented.

An abstract of the paper on the viral agents of acute encephalitis syndrome presented during the Institut Pasteur International Network Annual Scientific Meeting at Hong Kong, China, from November 22-23, 2010 is presented.