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Facility location, supply inventory and distribution, and evacuation planning are key operational functions in a humanitarian relief network, it is critical to integrate these three functions and schedule their activities jointly in a coordinated manner. Considering uncertain demands and evacuation rates of injured people, we develop a distributionally robust model for the multi-period humanitarian relief network design with multiple types of relief supplies. To solve the problem, we reformulate the proposed model into a mixed integer linear programme, and develop an enhanced branch-and-Benders-cut algorithm that incorporates some algorithm enhancements to solve the resulting model. Extensive numerical experiments show that: (i) the distributionally robust model provides more reliable and flexible solutions that perform the best when faced uncertainty over the deterministic and stochastic models; (ii) the algorithm enhancements are very effective to enhance the performance of the proposed algorithm, which can reduce the CPU time by up to 9.75%∼41.64% on average; (iii) the integrated solution approach is more beneficial to solve the problem when comparing with a sequential solution approach; and (iv) some model parameters have significant impact on the solution structure, which can help decision maker set proper parameters to achieve the desired trade-off among the considered metrics. [ABSTRACT FROM AUTHOR]

Hookworms are one of the most prevalent and important parasites, infecting ~500 million people worldwide. Hookworm disease is among the leading causes of iron-deficiency anemia in the developing world and is associated with significant growth stunting and malnutrition. In humans, hookworms appear to impair memory and other forms of cognition, although definitive data are hard to come by. Here we study the impact of a human hookworm parasite, Ancylostoma ceylanicum, on cognition in hamsters in a controlled laboratory setting. We developed tests that measure long-term memory in hamsters. We find that hookworm-infected hamsters were fully capable of detecting a novel object. However, hookworm-infected hamsters were impaired in detecting a displaced object. Defects could be discerned at even at low levels of infection, whereas at higher levels of infection, hamsters were statistically unable to distinguish between displaced and non-displaced objects. These spatial memory deficiencies could not be attributed to defects in infected hamster mobility or to lack of interest. We also found that hookworm infection resulted in reproducible reductions in diversity and changes in specific taxanomic groups in the hamster gut microbiome. These data demonstrate that human hookworm infection in a laboratory mammal results in a specific, rapid, acute, and measurable deficit in spatial memory, and we speculate that gut alterations could play some role in these cognitive deficits. Our findings highlight the importance of hookworm elimination and suggest that finer tuned spatial memory studies be carried out in humans.