Permafrost dynamics and the risk of anthrax transmission: a modelling study

A recent outbreak of anthrax disease, severely affecting reindeer herds in Siberia, has been reportedly associated to the presence of infected carcasses or spores released from the active layer over permafrost, which is thawing and thickening at increasing rates, thus underlying the re-emerging nature of this pathogen in the Arctic region because of warming temperatures. Anthrax is a global zoonotic and epizootic disease, with a high case-fatality ratio in infected animals. Its transmission is mediated by environmental contamination through highly resistant spores which can persist in the soil for several decades. Here we develop and analyze a new epidemiological model for anthrax transmission that is specifically tailored to the Arctic environmental conditions. The model describes transmission dynamics including also herding practices (e.g. seasonal grazing) and the role of the active layer over permafrost acting as a long-term storage of spores that could be viable for disease transmission during thawing periods. Model dynamics are investigated through linear stability analysis, Floquet theory for periodically forced systems, and a series of simulations with realistic forcings. Results show how the temporal variability of grazing and active layer thawing may influence the dynamics of anthrax disease and, specifically, favor sustained pathogen transmission. Particularly warm years, favoring deep active layers, are shown to be associated with an increase risk of anthrax outbreaks, and may also foster infections in the following years. Our results enable preliminary insights into measures (e.g. changes in herding practice) that may be adopted to decrease the risk of infection and lay the basis to possibly establish optimal procedures for preventing transmission; furthermore, they elicit the need of further investigations and observation campaigns focused on anthrax dynamics in the Arctic environment

Development of Detailed Chemistry Models for Boundary Layer Catalytic Recombination

During the (re-)entry phase of a space vehicle, the gas flow in the shock layer can be in a state of strong thermal non-equilibrium. Under these circumstances, the population of the internal energy levels of the atoms and molecules of the gas deviates from the Boltzmann distribution. A substantial increase of the heat flux transferred from the gas to the vehicle is possible, as the thermal protection system of the vehicle acts as a catalyzer. The objective of the paper is to show how thermal non-equilibrium and catalysis can jointly influence wall heat flux predictions. In order to study thermal non-equilibrium effects a coarse-grained State-to-State model for nitrogen is used coupled with a phenomenological model for catalysis. From the numerical simulations performed, an important effect on the heat flux has been observed due to the interaction of catalysis and thermal non-equilibrium at the wall

A year-round measurement of water-soluble trace and rare earth elements in arctic aerosol: Possible inorganic tracers of specific events

This study presents the year-round variability of the water-soluble fraction of trace elements (wsTE) and rare earth elements (wsREE) among size segregated airborne particulate matter samples collected at Ny-Å lesund in the Svalbard Archipelago from 26 February 2018 to 26 February 2019. Six different aerosol dimensional fractions were collected using a multi-stage Andersen impactor to better understand local and global circulation with the aim of disentangling the source of inorganic tracers from specific natural or anthropogenic sources. The wsTE and wsREE content, especially in the finest fractions in remote areas, is primarily related to long-range transport and it gives valuable information on (1) the global circulation, (2) the natural sources and (3) the contribution of human activities to aerosol composition. A Factor Analysis was applied to the dataset, including levoglucosan and methanesulfonic acid (MSA), to assess the possibility of using certain inorganic tracers as indicators of specific transport events or circulation regimes. We also investigate back-trajectories to determine potential source areas

Occurrence and phase distribution of benzothiazoles in untreated highway stormwater runoff and road dust

The study about how tyre-derived particles can potentially worsen the water quality and how traffic pollution markers can affect the environment is crucial for environmental management. Road emissions are known to contribute to pollution in various environments, and benzothiazoles and their derivates can be used to trace pollutant inputs related to surface runoff in the aquatic system. A total of eight benzothiazoles were determined in highway stormwater runoff and road dust collected from February to August 2022 near Venice (Casale sul Sile, Veneto Region, Italy). A new analytical method was validated, by using an UHPLC system coupled to a mass spectrometer (triple quadrupole). The target compounds were determined in both dissolved phase and suspended particulate matter of runoff, and the road dust samples were divided into seven fractions depending on particle diameters to understand the fraction partitioning. The results indicate that 2-SO3H-BTH was the most concentrated benzothiazole in all the analysed substrates, suggesting tyre debris as the main source because it is usually used in the vulcanization process. 2-SO3H-BTH reached a mean concentration of 115 +/- 59 mu g L-1, 4 +/- 3 mu g L-1, and 411 +/- 441 mu g Kg(-1) for dissolved phase, suspended particulate matter, and road dust, respectively, while 2-OH-BTH and BTH showed values about an order of magnitude lower. The size distribution of most BTHs suggests that they are distributed in the finest fraction of road dust. An exception was given by 2-SCNMeS-BTH being present only in particles with a diameter > 1 mm

Second-generation Thienopyridine use is not Associated with Better Early Perioperative Outcome During Carotid Stenting

AbstractObjectiveManagement of anti-platelet therapy during carotid artery stenting (CAS) is mainly based on indirect evidence from coronary stenting experience. There is common agreement on the use of thienopyridine (mainly second-generation) during CAS, but some patients are unsuitable for clopidogrel treatment and data on the benefit of its use in large CAS populations are lacking. The aim of this study was to investigate whether clopidogrel was associated with reduced perioperative morbidity in patients undergoing CAS.MethodsConsecutive patients undergoing CAS for primary carotid stenosis from 2004 to 2009 were reviewed. The independent association of clopidogrel and perioperative morbidity was assessed using multivariable analysis.ResultsA total of 1083 patients were treated (29% females, mean age 71.6 years); 825 (76%) patients were given clopidogrel starting before treatment. Clopidogrel use was associated with a non-significant reduction of perioperative stroke/death (4.3% vs. 2.4%; p = 0.13) and disabling stroke (1.2% vs. 1.0%; p = 1) rates. The non-significant stroke/death difference was similar in symptomatic (5.8% vs. 4.0%, p = 0.37) and asymptomatic (3.7% vs. 1.9%; p = 0.17) patients. After adjusting for demographics, co-morbidities and other therapies with multivariable analysis, clopidogrel use failed to show any significant independent association in decreasing operative risks. The only independent protective factor was use of statins (p = 0.010). The additional use of dual anti-platelet therapy did not add any advantage to the use of clopidogrel alone.ConclusionsThe suggested benefit of clopidogrel in decreasing the incidence of complications in patients undergoing CAS may be overestimated due to the overlapping effect of other more relevant factors (e.g., pleiotropy and plaque stabilisation from statins). More data and level I evidence are needed to understand which is the best medical management of CAS that will help improve outcomes of the procedure

High-altitude glacier archives lost due to climate change-related melting.

Global warming has caused widespread surface lowering of mountain glaciers. By comparing two firn cores collected in 2018 and 2020 from Corbassière glacier in Switzerland, we demonstrate how vulnerable these precious archives of past environmental conditions have become. Within two years, the soluble impurity records were destroyed by melting. The glacier is now irrevocably lost as an archive for reconstructing major atmospheric aerosol components

The disinfection by-products are in the air: Aerosol measurements in the urban area of Venice

Haloacetic acids (HAAs) are usually taken to be man-made, regularly determined in drinking water as disinfection by-products; yet they have been demonstrated as a probable photooxidation products from atmospheric halogenated hydrocarbons. Here we determined a total of fourteen HAAs, including for the first time iodinatedHAAs, in aerosol samples collected from April to June 2023 at Parco Bissuola (urbanized area of Venice) and Rio Novo (Venice island). The study provides a first insight and source identification about the anthropogenic or natural origin of HAAs. To fulfil this aim, we improved existing methods with a highly sensitive technique by using high pressure anion exchange chromatography coupled to a triple quadrupole mass spectrometer. Five HAAs have been found to be above the detection limits at both sites, and the major source should be attributed to a mixed contribution from atmospheric oxidation of both organic precursor, sea spray and a minor contribution of an external swimming pool located near the Parco Bissuola site. Considering the presence of iodinated HAAs and their cytotoxicity, the present study also provides a basis for the assessment of risks for humans

The Occurrence of Glyphosate and its Degradation Products in the Urban Stormwater: A Short Review

Due to urbanization and industrialization, water pollution is now one of the major environmental challenges of the twenty-first century. Considering the increasing of agricultural and non-agricultural settings in the last decades, the investigation of the relationship between such pesticides and urban stormwater is critical to understand how urban, residential, and industrialized areas can affect environmental safety. Recently, scientific interest has grown in stormwater chemical characterization with the aim to define its impacts in the environment and possibly to make it potable water. In this context, glyphosate, glufosinate, and their degradation products have been identified as the key knowledge gap for the chemical characterization of stormwater. Research investments are needed for a better understanding of the highly polar pesticides to estimate their load, source, and dispersion of urban runoff due to residential use of herbicides. Furthermore, a more comprehensive study of wet and dry deposition and spray drift should be considered for a correct evaluation of source apportionment

Focal Cerebral Infarction in Newborn: Description of Three Cases:

We observed 3 full-term newborns with focal ischemic injury of the middle cerebral artery (MCA), in which diagnosis of MCA stroke was suspected by US and confirmed by CT scan and MRI. A four-year follow-up was carried out to study the effect of neonatal stroke on neurodevelopmental outcome. All children had a history of pre-perinatal risk factors: neonatal cerebral infarction in term infants, in fact, has many possible causes, including bacterial meningitis, inherited or acquired coagulopathies, trauma and hypoxia-ischemia. The prognosis of neonatal MCA infarction depends on early diagnosis, on the CNS plasticity mechanism and, finally, on medical therapy and neuropsychological rehabilitation

Late Holocene records of fire and human presence in New Zealand

New Zealand, and the South Island in particular, can be considered an excellent test site for the study of the\ud early impact of humans on the environment for two main reasons: the Polynesian settlement occurred only\ud about 700-800 y BP and resulted in abrupt and huge landscape modifications. Burning forest for land clearance\ud impacted dramatically on an ecosystem that was not adapted to fire, changing the composition of the vegetation\ud as documented by sedimentary charcoal and pollen records. Although charcoal data give incontrovertible\ud evidence of some unprecedented fire events right after the arrival of the Maori, its significance as a tracer for local\ud and anthropogenic fire events has been questioned, stressing the need for new markers to confirm and complete the information about human presence and its effective impact.\ud In the present work, faecal sterols and polycyclic aromatic hydrocarbons (PAHs) were individuated as suitable\ud molecular markers and analyzed by GC-MS in a sediment core from Lake Kirkpatrick, located in the Lake\ud Wakatipu catchment at 570 m a.s.l. in the South Island of New Zealand. Coprostanol accounts for about 60%\ud of total sterol content in human faeces, being much less relevant in animal dejections. Together with its\ud degradation product epi-coprostanol, it is well conserved in sedimentary archives and can be highly useful in\ud paleoenvironmental reconstructions of human settlements. PAHs are produced in relevant amounts by combustion in conditions of oxygen depletion, and diagnostic ratios (DR) between specific molecules can be used for inferring fuel and sources.\ud The charcoal record for Lake Kirkpatrick shows major fire episodes around AD 1350, confirmed by corresponding high levels of PAHs ascribable to biomass burning (as further evidenced by DR) at c. AD 1350. Moreover, the same trend is observed also in the fluxes of coprostanol and epi-coprostanol, whose sum results in two peaks at c. AD 1346 and 1351. This finding confirms not only the massive presence of humans in the area and the large use of fire at the time, but also complements and refines the reconstructions enabled by charcoal analysis