In this paper, the elevated temperature buckling performance and design of cold-formed square, rectangular and circular hollow section columns made of stainless steel is studied through a numerical modelling investigation. The finite element analysis software Abaqus was employed to perform the simulations, where the validity of the models was established by replicating the results of flexural buckling tests at both elevated and room temperatures from literature test programmes. In total, twelve square (SHS) and rectangular (RHS) hollow section columns tested at elevated temperature and eleven circular (CHS) hollow section columns tested at room temperature were simulated. Following this, a comprehensive numerical parametric investigation was performed to systematically assess the effect of variation of the governing parameters including the grade of stainless steel (austenitic, duplex and ferritic) and the elevated temperature member slenderness (λ ̅ θ = 0.1-2.0) for all considered cross-section shapes with the addition of the aspect ratio of the cross-section (h/b = 1.0 and 1.5) and the column axis of buckling (major and minor) for the SHS and RHS. The applicability and accuracy of the design methods recommended in EN 1993-1-2 and the Design Manual for Stainless Steel Structures were carefully assessed on the basis of the numerical flexural buckling performance results. New buckling formulations for the fire design of cold-formed stainless steel SHS/RHS and CHS columns were proposed, and their suitability was confirmed by means of reliability analysis.

Stainless steel hollow sections have been used in building constructions for a number of years due to their durability and superior mechanical properties. However, they are less favourable than the carbon steel counterpart owing to their relatively high cost. A new, low nickel content stainless steel (EN 1.4162) or commonly referred as 'lean duplex' has been developed; which has over two times the strength of the more familiar austenitic stainless steel but at approximately half the cost. This more economical alternative would definitely be an attractive option to the construction industry. This paper presents the behaviour of axially loaded concrete filled composite stub columns with lean duplex stainless square hollow sections. A series of tests was performed to consider the behaviour of short composite stainless steel columns under axial compressive loading, covering lean duplex stainless steel square hollow sections filled with normal to high strength concrete. Based on the experimental studies, a modified equation based on the current Eurocode 4 on steel concrete composite structures is proposed.

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Despite substantial progress in recent years to improve the design guidance for high strength steel (HSS) structural elements, this has mainly been for ambient conditions with their fire response still in need of further research. Accordingly, this paper reports on an investigation into the structural performance of unprotected HSS hollow section columns in fire. Finite element models of columns made from square, circular and rectangular hollow sections are developed and are validated against test data at ambient and elevated temperature. The validated models are employed to perform parametric studies to assess the influence of a range of variables such as the grades of HSS, levels of temperature exposure and cross-sectional geometry. The structural fire design resistance method for a column given in the Eurocode is assessed based on the FE results. Consequently, new buckling curves are proposed, which provide a more accurate prediction of the real capacity and reliability analysis is also performed on the new proposed design formulations.

Phylum apicomplexan consists of parasites like Plasmodium and Toxoplasma. These obligate intracellular parasites enter host cells via an energy-dependent process using a specialized machinery called glideosome. In the present study, we used Plasmodium falciparum GAP 50, a glideosome-associated protein as a target to screen 951 different compounds from diverse chemical libraries. Using different screening methods, eight compounds, Hayatinine, Curine, MMV689758 (Bedaquiline), MMV1634402 (Brilacidin), and MMV688271, MMV782353, MMV642550, and USINB4-124-8 were identified which showed promising binding affinity (KD < 75 µM) along with sub-micromolar range anti-parasitic efficacy and selectivity index for malaria parasite > 100 fold. These eight compounds were effective against the chloroquine-resistant PfINDO and artemisinin-resistant, PfCam 3.1R359T strain. Studies on the effect of these compounds at asexual blood stages showed that these eight compounds act differently at different developmental stages, indicating the binding of these compounds to other Plasmodium proteins besides binding to PfGAP50. We further studied the effect of compounds in vivo P. berghei mouse model of malaria. Importantly, orally delivered Bedaquiline (50 mg/Kg b. wt.) showed substantial suppression of parasitemia, and three out of seven mice were cured of the infection. Thus, our study provides new scaffolds for the development of antimalarials that may act at multiple Plasmodium life cycle stages.