New environmental and spatial approach to Tiwanaku World Heritage site (Bolivia) using remote sensing (UAV and satellite images)

This paper analyses the research carried out in the Tiwanaku World Heritage site in Bolivia, using Unmanned Aerial Vehicles (UAV) and satellite images. The combined use of images with different scales has made it possible to locate many archaeological structures unknown to date (drainage systems, walls, circular crop marks and a possible dock). The Sentinel-2 images, which were processed using principal components analysis and histogram equalization, show the river beds, flood-prone areas and several buried drainage channels surrounding the most important structures. The archaeological evidence obtained with the DTM and natural colour / multispectral images enables us to contrast a new dimension of land and water uses that goes beyond what was known to date. In the same way, these images enable us to understand in detail the environmental characteristics, land use, building distribution and flood defence structures of the Tiwanaku culture throughout its history, within the context of the environmental conditions of the Bolivian altiplano. This investigation allowed collection of new information and posed questions on the relationship of this site with water, as well as a better understanding of the extent and habitat features of this historical population

Contemporary use of cefazolin for MSSA infective endocarditis: analysis of a national prospective cohort

Objectives: This study aimed to assess the real use of cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infective endocarditis (IE) in the Spanish National Endocarditis Database (GAMES) and to compare it with antistaphylococcal penicillin (ASP). Methods: Prospective cohort study with retrospective analysis of a cohort of MSSA IE treated with cloxacillin and/or cefazolin. Outcomes assessed were relapse; intra-hospital, overall, and endocarditis-related mortality; and adverse events. Risk of renal toxicity with each treatment was evaluated separately. Results: We included 631 IE episodes caused by MSSA treated with cloxacillin and/or cefazolin. Antibiotic treatment was cloxacillin, cefazolin, or both in 537 (85%), 57 (9%), and 37 (6%) episodes, respectively. Patients treated with cefazolin had significantly higher rates of comorbidities (median Charlson Index 7, P <0.01) and previous renal failure (57.9%, P <0.01). Patients treated with cloxacillin presented higher rates of septic shock (25%, P = 0.033) and new-onset or worsening renal failure (47.3%, P = 0.024) with significantly higher rates of in-hospital mortality (38.5%, P = 0.017). One-year IE-related mortality and rate of relapses were similar between treatment groups. None of the treatments were identified as risk or protective factors. Conclusion: Our results suggest that cefazolin is a valuable option for the treatment of MSSA IE, without differences in 1-year mortality or relapses compared with cloxacillin, and might be considered equally effective