Environmental geotechnics: Challenges and opportunities in the post-Covid-19 world

The outbreak of the coronavirus disease 2019 (Covid-19) pandemic not only has created a health crisis across the world but is also expected to impact negatively the global economy and societies at a scale that is maybe larger than that of the 2008 financial crisis. Simultaneously, it has inevitably exerted many negative consequences on the geoenvironment on which human beings depend. The current paper articulates the role of environmental geotechnics in elucidating and mitigating the effects of the current pandemic. It is the belief of all authors that the Covid-19 pandemic presents not only significant challenges but also opportunities for the development of the environmental geotechnics field. This discipline should make full use of geoenvironmental researchers' and engineers' professional skills and expertise to look for development opportunities from this crisis, to highlight the irreplaceable position of the discipline in the global fight against pandemics and to contribute to the health and prosperity of communities, to serve humankind better. In order to reach this goal while taking into account the specificity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the uncertainty of its environmental effects, it is believed that more emphasis should be placed on the following research directions: pathogen-soil interactions; isolation and remediation technologies for pathogen-contaminated sites; new materials for pathogen-contaminated soil; recycling and safe disposal of medical wastes; quantification of uncertainty in geoenvironmental and epidemiological problems; emerging technologies and adaptation strategies in civil, geotechnical and geoenvironmental infrastructures; pandemic-induced environmental risk management; and modelling of pathogen transport and fate in geoenvironment, among others. Moreover, Covid-19 has made it clear to the environmental geotechnics community the importance of urgent international co-operation and of multidisciplinary research actions that must extend to a broad range of scientific fields, including medical and public health disciplines, in order to meet the complexities posed by the Covid-19 pandemic

A Global Fireball Observatory

The world's meteorite collections contain a very rich picture of what the early Solar System would have been made of, however the lack of spatial context with respect to their parent population for these samples is an issue. The asteroid population is equally as rich in surface mineralogies, and mapping these two populations (meteorites and asteroids) together is a major challenge for planetary science. Directly probing asteroids achieves this at a high cost. Observing meteorite falls and calculating their pre-atmospheric orbit on the other hand, is a cheaper way to approach the problem. The Global Fireball Observatory (GFO) collaboration was established in 2017 and brings together multiple institutions (from Australia, USA, Canada, Morocco, Saudi Arabia, the UK, and Argentina) to maximise the area for fireball observation time and therefore meteorite recoveries. The members have a choice to operate independently, but they can also choose to work in a fully collaborative manner with other GFO partners. This efficient approach leverages the experience gained from the Desert Fireball Network (DFN) pathfinder project in Australia. The state-of-the art technology (DFN camera systems and data reduction) and experience of the support teams is shared between all partners, freeing up time for science investigations and meteorite searching. With all networks combined together, the GFO collaboration already covers 0.6% of the Earth's surface for meteorite recovery as of mid-2019, and aims to reach 2% in the early 2020s. We estimate that after 5 years of operation, the GFO will have observed a fireball from virtually every meteorite type. This combined effort will bring new, fresh, extra-terrestrial material to the labs, yielding new insights about the formation of the Solar System.Comment: Accepted in PSS. 19 pages, 9 figure

Current Wildland Fire Patterns and Challenges in Europe: A Synthesis of National Perspectives

Changes in climate, land use, and land management impact the occurrence and severity of wildland fires in many parts of the world. This is particularly evident in Europe, where ongoing changes in land use have strongly modified fire patterns over the last decades. Although satellite data by the European Forest Fire Information System provide large-scale wildland fire statistics across European countries, there is still a crucial need to collect and summarize in-depth local analysis and understanding of the wildland fire condition and associated challenges across Europe. This article aims to provide a general overview of the current wildland fire patterns and challenges as perceived by national representatives, supplemented by national fire statistics (2009–2018) across Europe. For each of the 31 countries included, we present a perspective authored by scientists or practitioners from each respective country, representing a wide range of disciplines and cultural backgrounds. The authors were selected from members of the COST Action “Fire and the Earth System: Science & Society” funded by the European Commission with the aim to share knowledge and improve communication about wildland fire. Where relevant, a brief overview of key studies, particular wildland fire challenges a country is facing, and an overview of notable recent fire events are also presented. Key perceived challenges included (1) the lack of consistent and detailed records for wildland fire events, within and across countries, (2) an increase in wildland fires that pose a risk to properties and human life due to high population densities and sprawl into forested regions, and (3) the view that, irrespective of changes in management, climate change is likely to increase the frequency and impact of wildland fires in the coming decades. Addressing challenge (1) will not only be valuable in advancing national and pan-European wildland fire management strategies, but also in evaluating perceptions (2) and (3) against more robust quantitative evidence

Immunohistochemical detection of Lawsonia intracellularis in tissue section from pigs

The aim of the present study was to develop an immunohistochemical method (IHC) for detection of Lawsonia intracellularis (L. intracellularis) in formalin-fixed, paraffin embedded sections of intestines from pigs and to implement this method in differential diagnosis of swine diseases with diarrhea in postweaning pigs. The study was conducted on 165 sections of intestines (ileum, caecum and colon) collected from 76 pigs, representing 42 Polish pig farms. The animals included in the analysis suffered from diarrhea, with bloody or grey to brown feces, and were suspected of porcine proliferative enteropathy (PPE). Sections of intestines were analyzed for the presence of L. intracellularis by polymerase chain reaction (PCR) and IHC. Among 165 intestinal samples from pigs with diarrhea, L. intracellularis DNA was detected by PCR in 33 (20.0%) samples. In this group, 30 samples (18.2% of all the samples tested) were also found positive in IHC, while only 3 (1.8%) were IHC-negative. One hundred thirty-two (80.0%) samples were negative in both tests. The PCR- and IHC-positive samples originated from 11 pigs, 4- to 20-week old, from 8 farms. L. intracellularis antigen was visualized by IHC mostly in intestinal crypts and/or in mononuclear cells of the lamina propria). The positive signal in epithelial cells was observed close to the luminal borders, creating typical specifically stained rims around the crypt lumina.ą The results of the present study further confirm the usefulness of IHC in the detection of L. intracellularis antigen in the intestinal tissues