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Contribution of the paragenetic sequence of clay minerals to re-examination of the alteration zoning in the krafla geothermal system

This paper revisits the clay mineralogy of the “smectite” alteration zone in the Krafla geothermal field via the study of an exploratory well in which temperatures range from 40 °C to 215 °C. The clay alteration consists of several mineral assemblages superimposed in time and space, resulting from different stages of water-rock interaction. Trioctahedral clay minerals (chlorite, cor-rensite and sm

Automatic processing of time domain induced polarization data using supervised artificial neural networks

Processing of geophysical data is a time consuming task involving many different steps. One approach for accelerating and automating processing of geophysical data is to look towards machine learning (ML). ML encompasses a wide range of tools, which can be used to automate complicated and/or tedious tasks. We present strategies for automating the processing of time-domain induced polarization (IP)

Influence of hydrothermal alteration on the elastic behaviour and failure of heat-treated andesite from Guadeloupe

Studies on the mechanical behaviour of rocks, including volcanic rocks, usually seek for unaltered and simple material: rocks without macroscopic defects. However, volcanic rocks are often naturally altered due to the circulation of hydrothermal fluids. This alteration may influence mechanical and physical properties. Here, we study the effect of hydrothermal alteration on the elasticity and failu

Smectite quantification in hydrothermally altered volcanic rocks

In volcanic environments, the presence of smectite may indicate recent hydrothermal circulations. Smectite is also responsible for enhanced rock electrical conductivity, as well as mechanical weakening. Therefore, quantifying smectite is important in geothermal exploration. Smectite identification requires X-ray diffraction (XRD) but quantification based on XRD is time-consuming and not always acc

‘Everyone’s Annoyed’ : Leveraging Uncertainty in the Smell of Others

A growing literature illuminates the limits of claims made on the basis of sensory perception in scientized, rationalized, and bureaucratic contexts. How to understand exceptions to the rule – cases where claims based on sensory experience are taken at face value, even without corroborating evidence? Here, I focus on one such exception, in which citizen complaints about the smell of a small shanty

Molecular diagnostics of salmonella and campylobacter in human/animal fecal samples remain feasible after long-term sample storage without specific requirements

Rapid advances in the development of sequencing technologies, numbers of commercial providers and diminishing costs have made DNA-based identification and diagnostics increasingly accessible to doctors and laboratories, eliminating the need for local investments in expensive technology and training or hiring of skilled technicians. However, reliable and comparable molecular analyses of bacteria in

Advanced dental cleaning is associated with reduced risk of copd exacerbations – a randomized controlled trial

Purpose: Infections from the oral microbiome may lead to exacerbations of chronic obstructive pulmonary disease (COPD). We investigated whether advanced dental cleaning could reduce exacerbation frequency. Secondary outcomes were disease-specific health status, lung function, and whether the bacterial load and composition of plaque microbiome at baseline were associated with a difference in outcom

Influence of smectite and salinity on the imaginary and surface conductivity of volcanic rocks

We investigate the complex conductivity behaviour of natural volcanic rocks containing variable amounts of smectite in multi-salinity experiments. We compare the results with relationships established for sandstones. Considering only samples with little volume of metallic particles, we observe similar and small phase-angles at low frequency for all samples at all salinities (less than 25 mrad at 1

Electrical resistivity tomography and time-domain induced polarization field investigations of geothermal areas at Krafla, Iceland : Comparison to borehole and laboratory frequency-domain electrical observations

Interaction of H2S and basaltic rocks in volcanic geothermal areas can originate from natural up-flow of magmatic fluids or H2S artificial re-injection in relation to geothermal exploitation, both causing pyrite mineralization. We study the possibility to track these processes with electrical impedance field measurements. Electrical Resistivity Tomography (ERT) and Time- Domain Induced Polarizatio

Tracking Magmatic Hydrogen Sulfur Circulations Using Electrical Impedance : Complex Electrical Properties of Core Samples at the Krafla Volcano, Iceland

Interaction of H2S escaping from magma and basaltic rocks leads to pyrite mineralization, witnessing active hydrothermal circulation. We study the possibility to track this process using geoelectrical methods. Complex conductivity spectra of 30 core samples from the Krafla volcano, Iceland, measured in the laboratory, indicate that pyrite can be discriminated from other minerals present in volcani

The role of smectites in the electrical conductivity of active hydrothermal systems : Electrical properties of core samples from Krafla volcano, Iceland

The underground circulation of hot water, of interest for geothermal energy production, is often indirectly inferred from the presence of minerals formed by hydrothermal alteration at different temperatures. Clay minerals, such as smectite and chlorite, can be mapped from the surface using electrical soundings and give information about the structure of the geothermal system. Here, we investigate

Characterization of pre-analytical sample handling effects on a panel of Alzheimer's disease–related blood-based biomarkers : Results from the Standardization of Alzheimer's Blood Biomarkers (SABB) working group

Introduction: Pre-analytical sample handling might affect the results of Alzheimer's disease blood-based biomarkers. We empirically tested variations of common blood collection and handling procedures. Methods: We created sample sets that address the effect of blood collection tube type, and of ethylene diamine tetraacetic acid plasma delayed centrifugation, centrifugation temperature, aliquot vol

Bio-based nonionic antimicrobial polymers with isatin or indole functionality

Infections by pathogenic microorganisms remain one of the most serious concerns in several areas, particularly in hygienic applications. Antimicrobials have been used to combat these infections. Using small molecular antimicrobials as additives or coatings is an industrially adopted strategy. However, small antimicrobial agents always suffer from many drawbacks, such as leaching potential, toxicit

From Djerba to Glasgow : have declarations on tourism and climate change brought us any closer to meaningful climate action?

The United Nations has declared climate change a code-red for humanity and the 2020s the decisive decade to avoid dangerous climate disruption. The 26th Conference of the Parties in Glasgow, Scotland represents a milestone event and potentially the last chance to keep the Paris Climate Agreement 1.5 °C policy goal within reach. The tourism sector has responded to this critical moment by releasing

The long-term consequences of parental death in childhood on mortality and the role of socioeconomic status : evidence from Sweden at the turn of the 20th century

The death of a parent during childhood is a major traumatic event. While there is a good understanding of the early-life effects of parental loss, the evidence regarding its impact on adult mortality is still scarce. Accordingly, the aim of this article is to study the long-term consequences of parental loss on mortality with a particular focus on differences by socioeconomic status (SES) of the f

Network Modeling and Performance Evaluation for G.fast

G.fast is a gap-bridging broadband technology on the way to a fully optical access network. G.fast is deployed in hybrid fiber-copper access networks and aiming to offer ubiquitous low-cost and high-speed broadband. For network operators, it is crucial to determine the location from where to deploy G.fast, the expected network coverage, and the expected bit rates. In this paper, we perform network

Amyloid-β precursor protein processing and oxidative stress are altered in human iPSC-derived neuron and astrocyte co-cultures carrying presenillin-1 gene mutations following spontaneous differentiation

INTRODUCTION: Presenilin-1 (PSEN1) gene mutations are the most common cause of familial Alzheimer's disease (fAD) and are known to interfere with activity of the membrane imbedded γ-secretase complex. PSEN1 mutations have been shown to shift Amyloid-β precursor protein (AβPP) processing toward amyloid-β (Aβ) 1-42 production. However, less is known about whether PSEN1 mutations may alter the activi

Application of Airy beam light sheet microscopy to examine early neurodevelopmental structures in 3D hiPSC-derived human cortical spheroids

BACKGROUND: The inability to observe relevant biological processes in vivo significantly restricts human neurodevelopmental research. Advances in appropriate in vitro model systems, including patient-specific human brain organoids and human cortical spheroids (hCSs), offer a pragmatic solution to this issue. In particular, hCSs are an accessible method for generating homogenous organoids of dorsal