Tourists’ city trip activity program planning:a personalized stated choice experiment

New digital technologies support personalized recommender systems that can assist a tourist who wants to make a city tour. To develop a smart system that can give tourists an optimized complete activity program for their trip, it is not only important to know the preferences and interests of tourists but also whether they like combinations of activities/points of interest (POIs) or not. The aim of this study is to measure and predict tourists’ preferences for combinations of activities in planning a program during a city trip. A personalized stated choice experiment is developed and presented in a survey to a random sample of 238 respondents. Binary mixed logit models are estimated on the choice data collected. An advantage of this approach is that it allows estimation of covariances between city trip activities indicating whether they would act as complements or substitutes for a specific tourist in his/her city trip activity program. The model parameters provide information on combinations of activities and themes that tourists prefer during their city trip and that the recommender system can use to further fine-tune the recommendations of city trip programs and optimize the tourist experience

Antioxidant Sestrin-2 Redistribution to Neuronal Soma in Human Immunodeficiency Virus-Associated Neurocognitive Disorders

Sestrin-2 is involved in p53-dependent antioxidant defenses and in the maintenance of metabolic homeostasis. We hypothesize that sestrin-2 expression is altered in the brains of subjects diagnosed with human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) due to neuronal oxidative stress. We studied sestrin-2 immunoreactivity in 42 isocortex sections from HIV-1-infected subjects compared to 18 age-matched non-HIV controls and 19 advanced Alzheimer's disease (AD) cases. With HIV infection, the sestrin-2 immunoreactivity pattern shifted from neuropil predominance (N) to neuropil and neuronal-soma co-dominance (NS) and neuronalsoma predominance (S; P < 0.0001, Chi-square test for linear trend). Among HIV cases showing the NS or S pattern, HAND cases were preferentially associated with the S pattern (n = 10 of 20) compared to cognitively intact cases (n = 1 of 11; P = 0.047, Fisher's exact test). In AD brains, sestrin-2 immunoreactivity was mostly intense in the neuropil and co-localized with phospho-Tau immunoreactivity in a subset of neurofibrillary lesions. Phospho-Tau-immunoreactive neurofibrillary lesions were rare in HIV cases and their occurrence was not associated with HAND. Levels of isocortical 8-hydroxy-deoxyguanosine (marker of nucleic acid oxidation) immunoreactivity were not significantly altered in HAND cases compared to cognitively intact HIV cases. In conclusion, the sestrin-2 immunoreactivity redistribution to neuronal soma in HAND suggests unique involvement of sestrin-2 in the pathophysiology of HAND, which is different from the role of sestrin-2 in AD pathogenesis. Alternatively, the difference in sestrin-2 immunoreactivity distribution between HAND and AD may be related to different degrees of severity or stages of oxidative stress