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• Integration of ASET-RSET concept and FED concept into a risk index. • Map-based fire scenario design and fire risk evaluation design. • Incorporation of evacuation performance into fire risk evaluation. • Occupant weighted method for overall fire risk calculation. Fire is a critical threat to large buildings. With the fire smoke diffusion, the risk of injury and death exists over a wide area. To investigate the fire risk level of large buildings, a Risk Index is defined as the fractional effective dose at the moment of required safe egress time to model the maximum potential fire risk of an area. Then, the map-based method is adopted to acquire a Risk Index map for each fire scenario and a Risk Index scenario map for the whole building. Finally, the overall fire risk of a fire scenario and a building could be acquired by integrating the Risk Index in each area and the Risk Index scenario in each fire scenario. The platform of a subway station is taken as a case study to validate the applicability of the proposed method. The results indicate that the method provides a more detailed and accurate evaluation of fire risk distribution of each fire scenario and the whole platform. Besides, the proposed method can provide more flexible and adaptive evacuation strategy recommendations. The results could be used for future fire risk evaluation, worst fire scenario identification and evacuation strategy design in different buildings. [ABSTRACT FROM AUTHOR]

[Display omitted] • An improved Accimap framework is proposed for subway accident investigation. • A sub-system concept is introduced to model the multi-stage characteristics. • The internal logic of the Zhengzhou subway Line 5 waterlogging accident is analyzed. • The countermeasures taken by governments after the accident is summarized. The cause of major accidents provides valuable lessons for hazard prevention and management improvement. However, the investigation of major accidents in a social-technical system could be a challenge that requires inter-disciplinary approaches. Accimap, a system-oriented method in accident investigation, has been widely used around multiple industries. However, as a typical social-technical system with various internal and external interactions, system-oriented analysis has rarely been applied in subway systems. Therefore, the objective of this work is to enhance the Accimap framework to conduct a hierarchical investigation into the contributions of multiple factors to the Zhengzhou waterlogging accident and analyze the interconnections between factors during the accident's progression. To capture the multiple-stage characteristic of subway accidents, a sub-system concept is introduced. By studying the accident evolution in depot/construction subsystem, station/dispatch subsystem and tunnel/rescue subsystem, this work provides a detailed case study that reveals the underlying deficiencies in the emergency management of Chinese subway system. Besides, this work also reviewed the most important countermeasures and policies implemented by different levels of governments following the accident. By demonstrating the lessons learned from and improvements made after the major accident, the findings can support the accident prevention and policy making within the subway industry in the future. [ABSTRACT FROM AUTHOR]

For over 30 years, HIV/AIDS has wreaked havoc in the world. In the absence of an effective vaccine for HIV, development of new anti-HIV agents is urgently needed. We previously identified the antiviral activities of the scorpion-venom-peptidederived mucroporin-M1 for three RNA viruses (measles viruses, SARS-CoV, and H5N1). In this investigation, a panel of scorpion venom peptides and their derivatives were designed and chosen for assessment of their anti-HIV activities. A new scorpion venom peptide derivative Kn2-7 was identified as the most potent anti-HIV-1 peptide by screening assays with an EC50 value of 2.76αg/ml (1.65 αM) and showed low cytotoxicity to host cells with a selective index (SI) of 13.93. Kn2-7 could inhibit all members of a standard reference panel of HIV-1 subtype B pseudotyped virus (PV) with CCR5-tropic and CXCR4- tropic NL4-3 PV strain. Furthermore, it also inhibited a CXCR4-tropic replication-competent strain of HIV-1 subtype B virus. Binding assay of Kn2-7 to HIV-1 PV by Octet Red system suggested the anti-HIV-1 activity was correlated with a direct interaction between Kn2-7 and HIV-1 envelope. These results demonstrated that peptide Kn2-7 could inhibit HIV-1 by direct interaction with viral particle and may become a promising candidate compound for further development of microbicide against HIV-1. [ABSTRACT FROM AUTHOR]

Spill fires usually occur with liquid fuel storage and transportation, which may pose a threat to process safety and environmental protection. Analysis on the liquid layer spread and burning behavior is vital for preventing and mitigating spill fire accidents. In the study, a number of heptane continuous spill fire experiments on a fireproof glass sheet were conducted to better understand the spreading and burning of continuous spill fires. In the experiments, the liquid surface area, burning rate and heat transfer between liquid layer and the glass sheet were analyzed. The results showed that the heptane burning rate of spill fires was lower than that for pool fires of the same burning size. The experimental data showed that the radiative penetration through the liquid layer was mainly responsible for the lower burning rate at the quasi-steady burning phase. Based on the heat transfer process, a modified burning rate model of spill fires by considering the heat loss of liquid layer was developed and validated by the experimental data. [ABSTRACT FROM AUTHOR]

The induction of a strong mucosal immune response is essential to building successful HIV vaccines. Highly attenuated recombinant HIV vaccinia virus can be administered mucosally, but even high doses of immunization have been found unable to induce strong mucosal antibody responses. In order to solve this problem, we studied the interactions of recombinant HIV vaccinia virus Tiantan strain (rVTT-gagpol) in mucosal epithelial cells (specifically Caco-2 cell layers) and in BALB/c mice. We evaluated the impact of this virus on HIV antigen delivery and specific immune responses. The results demonstrated that rVTT-gagpol was able to infect Caco-2 cell layers and both the nasal and lung epithelia in BALB/c mice. The progeny viruses and expressed p24 were released mainly from apical surfaces. In BALB/c mice, the infection was limited to the respiratory system and was not observed in the blood. This showed that polarized distribution limited antigen delivery into the whole body and thus limited immune response. To see if this could be improved upon, we stimulated unpolarized budding of the virus and HIV antigens by treating both Caco-2 cells and BALB/c mice with colchicine. We found that, in BALB/c mice, the degree of infection and antigen expression in the epithelia went up. As a result, specific immune responses increased correspondingly. Together, these data suggest that polarized budding limits antigen delivery and immune responses, but unpolarized distribution can increase antigen expression and delivery and thus enhance specific immune responses. This conclusion can be used to optimize mucosal HIV vaccine strategies. [ABSTRACT FROM AUTHOR]