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By July 14, 2021, 81·3 % of adults (aged ≥18 years) in Chile had received a first SARS-CoV-2 vaccine and 72·3% had received a second SARS-CoV-2 vaccine, with the majority of people given Sinovac's inactivated CoronaVac vaccine (75·3% of vaccines dispensed) or Pfizer–BioNTech's mRNA BNT162b2 vaccine (20·9% of vaccines dispensed). Due to the absence of simultaneous real-world data for these vaccines, we aimed to compare SARS-CoV-2 IgG positivity between vaccines using a dynamic national monitoring strategy. From March 12, 2021, 28 testing stations for SARS-CoV-2 IgG detection were installed in hotspots based on cellular-phone mobility tracking within the most populated cities in Chile. Individuals voluntarily approaching the testing stations were invited to do a lateral flow test by finger prick and respond to a questionnaire on sociodemographic characteristics, vaccination status (including type of vaccine if one was received), variables associated with SARS-CoV-2 exposure, and comorbidities. We compared the proportion of individuals testing positive for anti-SARS-CoV-2 IgG across sites by week since vaccination between recipients of CoronaVac and BNT162b2. Unvaccinated participants served as a control population and were matched to vaccinated individuals on the basis of date of presentation to the testing station, gender, and age group. Individuals were excluded from the analysis if they were younger than 18 years, had no declared gender, had an invalid IgG test result, had previously tested positive for SARS-CoV-2 infection on PCR, could not recall their vaccination status, or had been immunised against COVID-19 with vaccines other than CoronaVac or BNT162b2. Here, we report data collected up to July 2, 2021. Of 64 813 individuals enrolled, 56 261 were included in the final analysis, of whom 33 533 (59·6%) had received at least one dose of the CoronaVac vaccine, 8947 (15·9%) had received at least one dose of the BNT162b2 vaccine, and 13 781 (24·5%) had not received a vaccine. SARS-CoV-2 IgG positivity during week 4 after the first dose of CoronaVac was 28·1% (95% CI 25·0–31·2; 220 of 783 individuals), reaching a peak of 77·4% (75·5–79·3; 1473 of 1902 individuals) during week 3 after the second dose. SARS-CoV-2 IgG positivity during week 4 after the first dose of the BNT162b2 vaccine was 79·4% (75·7–83·1; 367 of 462 individuals), increasing to 96·5% (94·9–98·1; 497 of 515 individuals) during week 3 after the second dose and remaining above 92% until the end of the study. For unvaccinated individuals, IgG seropositivity ranged from 6·0% (4·4–7·6; 49 of 810 individuals) to 18·7% (12·5–24·9; 28 of 150 individuals) during the 5 month period. Regression analyses showed that IgG seropositivity was significantly lower in men than women and in people with diabetes or chronic diseases for CoronaVac vaccine recipients (p<0·0001), and for individuals aged 60 years and older compared with people aged 18–39 years for both vaccines (p<0·0001), 3–16 weeks after the second dose. IgG seropositivity was lower after CoronaVac than after BNT162b2 and declined over time since vaccination for CoronaVac recipients but not BNT162b2 recipients. Prolonged IgG monitoring will allow further evaluation of seropositivity overtime, providing data, in conjunction with effectiveness studies, for possible future re-assessment of vaccination strategies. Instituto Sistemas Complejos de Ingeniería and Ministerio de Salud Chile. For the Spanish translation of the abstract see Supplementary Materials section.

By early May 2020, the number of new COVID-19 infections started to increase rapidly in Chile, threatening the ability of health services to accommodate all incoming cases. Suddenly, ICU capacity planning became a first-order concern, and the health authorities were in urgent need of tools to estimate the demand for urgent care associated with the pandemic. In this article, we describe the approach we followed to provide such demand forecasts, and we show how the use of analytics can provide relevant support for decision making, even with incomplete data and without enough time to fully explore the numerical properties of all available forecasting methods. The solution combines autoregressive, machine learning and epidemiological models to provide a short-term forecast of ICU utilization at the regional level. These forecasts were made publicly available and were actively used to support capacity planning. Our predictions achieved average forecasting errors of 4% and 9% for one- and two-week horizons, respectively, outperforming several other competing forecasting models.

Nirsevimab for the prevention of respiratory syncytial virus (RSV) was introduced in some countries in the northern hemisphere in 2023. Chile was the first to implement a universal strategy in the southern hemisphere. We aimed to evaluate the effectiveness and impact of nirsevimab during the 2024 RSV season in Chile. Roll-out of the strategy began on April 1, 2024, and ended on Sept 30, 2024, targeting infants born between April 1, 2024, and Sept 30, 2024 (seasonal newborn cohort), and infants born between Oct 1, 2023, and March 31, 2024 (catch-up cohort). Using historical surveillance and hospital discharge data from ten hospitals that perform universal RSV testing for all patients admitted due to lower respiratory tract infection (LRTI), we identified a set of ICD-10 codes most closely related to RSV admissions during the 2019, 2022, and 2023 RSV seasons. These codes were applied to a national database of three consolidated nationwide government registries to identify RSV-related LRTI hospitalisations (primary endpoint) among infants who received or did not receive nirsevimab. Secondary endpoints were RSV-related intensive care unit (ICU) admission, all-cause LRTI hospitalisation, and all-cause hospitalisation occurring at least 7 days after birth. Nirsevimab effectiveness was estimated using a stratified Cox proportional hazards model, calculated as (1 – hazard ratio) multiplied by 100, with 95% CIs. We also assessed the impact of nirsevimab by estimating, compared with a counterfactual scenario in which nirsevimab was never introduced, the averted number and relative reduction of cases, and the number needed to immunise to avoid one case. This study was registered with ClinicalTrials.gov, NCT06511687 (completed). Data for 157 709 infants with complete records were extracted from the consolidated database. After excluding 1247 infants with missing or corrupt data and 2289 infants whose immunisation status could not be determined, 154 173 infants were included in the primary analysis. The median age of infants was 6·27 months (IQR 3·20–9·17). 76 045 (49·32%) infants were female and 78 128 (50·68%) were male. 145 087 infants were immunised by the end of the strategy roll-out, with 72 246 (49·79%) in the catch-up cohort and 72 841 (50·21%) in the seasonal cohort. After controlling for age, sex, geographical area, and weeks of gestational age, combined effectiveness of nirsevimab (for catch-up and seasonal cohorts) against RSV-related LRTI hospitalisations was 76·41% (95% CI 72·57–79·72), against RSV-related ICU admissions was 84·94% (79·47–88·95), against all-cause LRTI hospitalisations was 66·50% (61·97–70·50), and against all-cause hospitalisations was 47·90% (44·35–51·21). We estimated a relative reduction of 77·46% in RSV-related LRTI hospitalisations, 30·05 averted cases per 1000 infants, and a number needed to immunise to prevent one RSV-related LRTI hospitalisation of 35. Chile's nirsevimab immunisation strategy significantly reduced RSV-related LRTI hospitalisations and more severe cases requiring intensive care. Our findings indicate a broader public health impact, with reductions also observed in all-cause LRTI hospitalisations. These results might encourage other countries to advance RSV prevention efforts. Instituto Sistemas Complejos de Ingeniería and the Ministry of Health of Chile. For the Spanish translation of the abstract see Supplementary Materials section.

This paper analyzes the efficiency of and the substitutability between three urban congestion management policies: transit subsidization, car congestion pricing, and dedicated bus lanes. The model features user heterogeneity, cross-congestion effects between cars and transit, intertemporal and total transport demand elasticities, and is simulated using data for London, UK and Santiago, Chile. We find that the substitutability between policies is large and, in particular, the marginal contribution of increased transit subsidies, as other policies are implemented first, diminishes rapidly. Bus lanes are an attractive way to increase frequencies and decrease fares without injecting public funds.

Despite the growing literature on loyalty program (LP) research, many questions remain underexplored. Driven by advancements in information technology, marketing analytics, and consumer interface platforms (e.g., mobile devices), there have been many recent developments in LP practices around the world. They impose new challenges and create exciting opportunities for future LP research. The main objective of this paper is to identify missing links in the literature and to craft a future research agenda to advance LP research and practice. Our discussion focuses on three key areas: (1) LP designs, (2) Assessment of LP performance, and (3) Emerging trends and the impact of new technologies. We highlight several gaps in the literature and outline research opportunities in each area.

The 2021 wave of SARS-CoV-2 infection in Chile was characterized by an explosive increase in ICU admissions, which disproportionately affected individuals younger than 60 years. This second wave was also accompanied by an explosive increase in Gamma (P.1) variant detections and the massive vaccine rollout. We unveil the role the Gamma variant played in stressing the use of critical care, by developing and calibrating a queueing model that uses data on new onset cases and actual ICU occupancy, symptom’s onset to ICU admission interval, ICU length-of-stay, genomic surveillance, and vaccine effectiveness. Our model shows that infection with the Gamma (P.1) variant led to a 3.5–4.7-fold increase in ICU admission for people younger than 60 years. This situation occurred on top of the already reported higher infection rate of the Gamma variant. Importantly, our results also strongly suggest that the vaccines used in Chile (inactivated mostly, but also an mRNA), were able to curb Gamma variant ICU admission over infections.

The tumor microenvironment (TME) of glioblastoma (GB) is characterized by an increased infiltration of immunosuppressive cells that attenuate the antitumor immune response. The participation of neutrophils in tumor progression is still controversial and a dual role in the TME has been proposed. In this study, we show that neutrophils are reprogrammed by the tumor to ultimately promote GB progression. Using and assays, we demonstrate the existence of bidirectional GB and neutrophil communication, directly promoting an immunosuppressive TME. Neutrophils have shown to play an important role in tumor malignancy especially in advanced 3D tumor model and Balb/c nude mice experiments, implying a time- and neutrophil concentration-dependent modulation. Studying the tumor energetic metabolism indicated a mitochondria mismatch shaping the TME secretome. The given data suggests a cytokine milieu in patients with GB that favors the recruitment of neutrophils, sustaining an anti-inflammatory profile which is associated with poor prognosis. Besides, glioma-neutrophil crosstalk has sustained a tumor prolonged activation via NETs formation, indicating the role of NFκB signaling in tumor progression. Moreover, clinical samples have indicated that neutrophil-lymphocyte ratio (NLR), IL-1β, and IL-10 are associated with poor outcomes in patients with GB. These results are relevant for understanding how tumor progression occurs and how immune cells can help in this process.

Abstract The concentration of copper in the soil increased with the intensification of agricultural activities, mainly in grape production areas and orchards as a result of the application of pesticides. Arbuscular mycorrhizal fungi make up the microbial biomass of the soil and appear as an alternative to be researched for the development of plants in an environment contaminated with copper. The purpose of this pot study was to analyze the influence of arbuscular mycorrhizal fungi on the development and content of copper in corn and sorghum plants. Soil treatments were: without inoculum (control) and two arbuscular mycorrhizal (Acaulospora scrobiculata and Rhizoglomus clarum) and five doses of copper (0, 100, 200, 300, and 400 mg Cu kg-1 soil); with seven repetitions. Plant height, stem diameter, number of tillers, root volume, shoot and root dry weight yields, shoot, root and grain Cu concentrations, pseudo-total soil Cu, percentage of mycorrhizal colonization and relative mycorrhizal efficiency index in reducing Cu concentration in root and shoot of corn and sorgum were evaluated. Morphological parameters of sorghum and corn were reduced with at high Cu doses in the soil, and the inoculation with Acaulospora scrobiculata and Rhizoglomus clarum resulted in greater development and lower Cu concentration in the dry mass of the shoot and root parts sorghum and corn plants. Resumo A concentração de cobre no solo aumentou com a intensificação das atividades agrícolas, principalmente em áreas de produção de uva e pomares, como resultado da aplicação de pesticidas. Fungos micorrízicos arbusculares compõem a biomassa microbiana do solo e aparecem como uma alternativa a ser pesquisada para o desenvolvimento de plantas em ambiente contaminado com cobre. O objetivo deste estudo em vasos foi analisar a influência dos fungos micorrízicos arbusculares no desenvolvimento e conteúdo de cobre em plantas de milho e sorgo. Os tratamentos do solo foram: sem inóculo (controle) e dois micorrízicos arbusculares (Acaulospora scrobiculata e Rhizoglomus clarum) e cinco doses de cobre (0, 100, 200, 300 e 400 mg Cu kg-1 solo); com sete repetições. Foram avaliados altura de planta, diâmetro do caule, número de perfilhos, volume de raiz, produtividade de matéria seca de parte aérea e raiz, concentrações de Cu em parte aérea, raiz e grão, Cu pseudo-total do solo, porcentagem de colonização micorrízica e índice de eficiência micorrízica relativa na redução da concentração de Cu em raiz e parte aérea de milho e sorgo. Os parâmetros morfológicos de sorgo e milho foram reduzidos com altas doses de Cu no solo, e a inoculação com Acaulospora scrobiculata e Rhizoglomus clarum resultou em maior desenvolvimento e menor concentração de Cu na massa seca das partes aérea e radicular de plantas de sorgo e milho.

We investigate airport peak-load pricing using a vertical structure of airport and airlines. We find that a profit-maximizing airport would charge higher peak and off-peak runway prices and a higher peak/off-peak price differential than a public airport. Consequently, airport privatization would lead to both fewer total passengers and fewer passengers in the peak period. Although peak-travelling passengers benefit from fewer delays, this low level of peak congestion is not efficient, suggesting that airport privatization cannot be judged based on its effect on congestion alone. We also examine pricing behaviour of a public airport constrained to charge a time independent price. /// On étudie la tarification de pointe dans une structure verticale d'aéroports et de compagnies d'aviation. On découvre qu'un aéroport qui maximise ses profits chargerait des prix plus élevés pour l'usage des pistes (tant aux heures de pointe qu'en autre temps) qu'un aéroport public, ainsi qu'un différentiel plus grand entre ces différents moments. En conséquence, la privatisation des aéroports va entraîner à la fois moins de passagers et moins de passagers aux heures de pointe. Même si ceux qui voyagent aux heures de pointe vont devoir subir moins de délais, cette moindre congestion n'est pas efficace. Voilà qui suggère qu'on ne doit pas évaluer la privatisation des aéroports seulement à l'aune de l'impact sur la congestion. Les auteurs examinent aussi les stratégies de tarification d'un aéroport public contraint à imposer une tarification qui ne peut varier selon le moment d'usage dans le temps.