Estimating the generation interval from the incidence rate, the optimal quarantine duration and the efficiency of fast switching periodic protocols for COVID‑19

The transmissibility of an infectious disease is usually quantified in terms of the reproduction number Rt representing, at a given time, the average number of secondary cases caused by an infected individual. Recent studies have enlightened the central role played by w(z), the distribution of generation times z, namely the time between successive infections in a transmission chain. In standard approaches this quantity is usually substituted by the distribution of serial intervals, which is obtained by contact tracing after measuring the time between onset of symptoms in successive cases. Unfortunately, this substitution can cause important biases in the estimate of Rt . Here we present a novel method which allows us to simultaneously obtain the optimal functional form of w(z) together with the daily evolution of Rt , over the course of an epidemic. The method uses, as unique information, the daily series of incidence rate and thus overcomes biases present in standard approaches. We apply our method to one year of data from COVID-19 officially reported cases in the 21 Italian regions, since the first confirmed case on February 2020. We find that w(z) has mean value z ≃ 6 days with a standard deviation a ≃ 1 day, for all Italian regions, and these values are stable even if one considers only the first 10 days of data recording. This indicates that an estimate of the most relevant transmission parameters can be already available in the early stage of a pandemic. We use this information to obtain the optimal quarantine duration and to demonstrate that, in the case of COVID-19, post-lockdown mitigation policies, such as fast periodic switching and/or alternating quarantine, can be very efficient

International corporations trading Brazilian soy are keystone actors for water stewardship

Transnational corporations play a major, but poorly constrained, role in reallocating global water resources. Here, we couple high-resolution, company-specific trade data with hydrological and crop models to estimate the virtual water trade of the top 9 transnational corporations that trade Brazilian soy. We identify 4429 virtual water flows connecting 1620 Brazilian municipalities with the top-10 soy importing countries and find that the total virtual water flow increased from 43 billion m3 to 100 billion m3 between 2004 and 2018. We find that the largest soy traders displace on average twice as much virtual water as top-importing countries, excluding China. For example, in 2018 one transnational corporation exported 15 Gm3, almost tripling the Netherlands’s virtual water import (the second largest importer at about 5 Gm3). Our findings highlight the importance of transnational corporations for achieving water stewardship and sustainable supply chains to support water resource security at municipal and international scales

Dirac Equation Studies in the Tunnelling Energy Zone

We investigate the tunnelling zone V0 < E < V0+m for a one-dimensional potential within the Dirac equation. We find the appearance of superluminal transit times akin to the Hartman effect.Comment: 12 pages, 4 figure

Adjuvant Treatment in Pancreatic Cancer: Shaping the Future of the Curative Setting

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease even in the early stages, despite progresses in surgical and pharmacological treatment in recent years. High potential for metastases is the main cause of therapeutic failure in localized disease, highlighting the current limited knowledge of underlying pathological processes. However, nowadays research is focusing on the search for personalized approaches also in the adjuvant setting for PDAC, by implementing the use of biomarkers and investigating new therapeutic targets. In this context, the aim of this narrative review is to summarize the current treatment scenario and new potential therapeutic approaches in early stage PDAC, from both a preclinical and clinical point of view. Additionally, the review examines the role of target therapies in localized PDAC and the influence of neoadjuvant treatments on survival outcomes

Nonhuman gamblers: lessons from rodents, primates, and robots

The search for neuronal and psychological underpinnings of pathological gambling in humans would benefit from investigating related phenomena also outside of our species. In this paper, we present a survey of studies in three widely different populations of agents, namely rodents, non-human primates, and robots. Each of these populations offers valuable and complementary insights on the topic, as the literature demonstrates. In addition, we highlight the deep and complex connections between relevant results across these different areas of research (i.e., cognitive and computational neuroscience, neuroethology, cognitive primatology, neuropsychiatry, evolutionary robotics), to make the case for a greater degree of methodological integration in future studies on pathological gambling

Clues on the origin of post-2000 earthquakes at Campi Flegrei caldera (Italy)

Acknowledgements We thank the INGV-OV staff involved in the management and maintenance of the seismic and GPS networks and Francesca Di Luccio for the data of the best located earthquakes. We acknowledge Valerio Acocella and an anonymous reviewer for the helpful comments that improved the clarity of the manuscript.This study has benefited from funding provided by INGV (project COHESO) by the Italian Presidenza del Consiglio dei Ministri Dipartimento della Protezione Civile (DPC), INGV-DPC Research Agreement 2012–2014, Progetto V2 “Precursori di eruzioni”. This paper does not necessarily represent DPC official opinion and policies. EdP has been partly supported by Spanish Project Ephestos, CGL2011-29499-C02-01 and KNOWAVES, TEC2015-68752. We wish to acknowledge the former contribution of Lorenzo Casertano, Oliveri del Castillo and Maria Teresa Quagliariello, who, in an early paper published on Nature in 1976, first discussed the importance of fluids in the dynamics of Campi Flegrei Caldera.Peer reviewedPublisher PD

Endothelial heme dynamics drive cancer cell metabolism by shaping the tumor microenvironment

The crosstalk among cancer cells (CCs) and stromal cells within the tumor microenvironment (TME) has a prominent role in cancer progression. The significance of endothelial cells (ECs) in this scenario relies on multiple vascular functions. By forming new blood vessels, ECs support tumor growth. In addition to their angiogenic properties, tumor-associated ECs (TECs) establish a unique vascular niche that actively modulates cancer development by shuttling a selected pattern of factors and metabolites to the CC. The profile of secreted metabolites is strictly dependent on the metabolic status of the cell, which is markedly perturbed in TECs. Recent evidence highlights the involvement of heme metabolism in the regulation of energy metabolism in TECs. The present study shows that interfering with endothelial heme metabolism by targeting the cell membrane heme exporter Feline Leukemia Virus subgroup C Receptor 1a (FLVCR1a) in TECs, resulted in enhanced fatty acid oxidation (FAO). Moreover, FAO-derived acetyl-CoA was partly consumed through ketogenesis, resulting in ketone bodies (KBs) accumulation in FLVCR1a-deficient TECs. Finally, the results from this study also demonstrate that TECs-derived KBs can be secreted in the extracellular environment, inducing a metabolic rewiring in the CC. Taken together, these data may contribute to finding new metabolic vulnerabilities for cancer therapy