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Hydraulic fracturing (HF) operations are widely associated with induced seismicity in the Western Canadian Sedimentary Basin. This study correlates injection parameters of 12,903 HF stages in the Kiskatinaw area in northeast British Columbia with an enhanced catalog containing 40,046 earthquakes using a supervised machine learning approach. It identifies relevant combinations of geological and operational parameters related to individual HF stages in efforts to decipher fault activation mechanisms. Our results suggest that stages targeting specific geological units (here, the Lower Montney formation) are more likely to induce an earthquake. Additional parameters positively correlated with earthquake likelihood include target formation thickness, injection volume, and completion date. Furthermore, the COVID‐19 lockdown may have reduced the potential cumulative effect of HF operations. Our results demonstrate the value of machine learning approaches for implementation as guidance tools that help facilitate safe development of unconventional energy technologies. Plain Language Summary: Hydraulic fracturing (HF), a technique used in unconventional energy production, increases rock permeability to enhance fluid movement. Its use has led to an unprecedented increase of associated earthquakes in the Western Canadian Sedimentary Basin in the last decade, among other regions. Numerous studies have investigated the relationship between induced earthquakes and HF operations, but the connection between specific geological and operational parameters and earthquake occurrence is only partly understood. Here, we use a supervised machine learning approach with publicly available injection data from the British Columbia Oil and Gas Commission to identify influential HF parameters for increasing the likelihood of a specific operation inducing an earthquake. We find that geological parameters, such as the target formation and its thickness, are most influential. A small number of operational parameters are also important, such as the injected fluid volume and the operation date. Our findings demonstrate an approach with the potential to develop tools to help enable the continued development of alternative energy technology. They also emphasize the need for public access to operational data to estimate and reduce the hazard and associated risk of induced seismicity. Key Points: We use supervised machine learning to investigate the relationship between hydraulic fracturing operation parameters and induced seismicityGeological properties and a limited number of operational parameters predominantly influence the probability of an induced earthquakeThe approach has the potential to guide detailed investigations of injection parameters critical for inducing earthquakes [ABSTRACT FROM AUTHOR]

The static stress drop of an earthquake is an indicator of the stress state of a specific fault before rupture initiation. The stress state is primarily controlled by the ambient stress field, fault strength, fault complexity, and the presence of fluids. This study aims to investigate the spatio‐temporal distribution of static stress drop values of the 2016–2017 multi‐fault rupture seismic sequence in central Italy, which includes three earthquakes with Mw ≥ 5.9 (Amatrice, Visso, and Norcia earthquakes), and over 95,000 aftershocks (M 0.5–6.5). We estimate stress drop values using a circular crack model with corner frequency and seismic moment estimates from single‐spectra fitting, a cluster‐event method, and spectral‐ratio fitting. The temporal distribution of stress drop values shows an apparent increase of stress drop following a large earthquake (Mw ≥ 5.9). The spatial distribution shows comparably high stress drop values for early aftershocks surrounding the mainshock rupture area. High stress drop events correlate with fault complexity, such as fault intersections at depth and reactivated thrust fronts. We observe a constant stress drop for Mw ≥ ∼3, in contrast to previous studies. Instrument response and signal‐to‐noise bandwidth limitations likely govern the observed decrease in stress drop with decreasing magnitude for events with Mw ≤ 3. The spatio‐temporal distribution of stress drop values in a complex seismic sequence could support a more complete understanding of the earthquake rupture process and the evolution of seismic sequences. It could also highlight areas where stress loading is focused, which would have implications for short and intermediate term seismic hazard estimates. Plain Language Summary: The ongoing earthquake sequence that began in 2016 in central Italy has produced a significant physical imprint on the earth's surface from the rupture of the three largest events, and has changed the state of stress within the crust. The earthquakes release stored stress in some regions, which can be measured indirectly by the waveforms recorded on seismometers (seismograms), and increase stress in others. Here we analyze seismograms, including those of numerous small earthquakes, to estimate source properties such as the physical size of the rupture surface and the corresponding fault slip. Source properties relate to the amount of stress released by an earthquake and are relevant to learning about the fault rupture process and the redistribution of stress during the evolution of a seismic sequence. We use a combination of approaches to find that the occurrence of large earthquakes leads to a temporal increase of stress in the vicinity of the ruptured fault, and that high stress release correlates with places where faults intersect in the subsurface. Our findings provide a more comprehensive picture of the complex seismic sequence and highlight areas that could influence short and intermediate term seismic hazard estimates. Key Points: The AVN seismic sequence shows significant spatio‐temporal variations in stress drop valuesHigher stress drop values correlate with increasing fault complexity and stress field heterogeneityInstrument response and signal‐to‐noise limitations likely govern stress drop scaling for events with for M < ∼3 [ABSTRACT FROM AUTHOR]

Abstract: The hypoxia‐inducible factor (HIF) co‐ordinates the adaptive transcriptional response to hypoxia in metazoan cells. The hypoxic sensitivity of HIF is conferred by a family of oxygen‐sensing enzymes termed HIF hydroxylases. This family consists of three prolyl hydroxylases (PHD1–3) and a single asparagine hydroxylase termed factor inhibiting HIF (FIH). It has recently become clear that HIF hydroxylases are functionally non‐redundant and have discrete but overlapping physiological roles. Furthermore, altered abundance or activity of these enzymes is associated with a number of pathologies. Pharmacological HIF‐hydroxylase inhibitors have recently proven to be both tolerated and therapeutically effective in patients. In this review, we focus on the physiology, pathophysiology and therapeutic potential of the PHD1 isoform, which has recently been implicated in diseases including inflammatory bowel disease, ischaemia and cancer. [ABSTRACT FROM AUTHOR]

Vast germplasm collections are accessible but their use for crop improvement is limited—efficiently accessing genetic diversity is still a challenge. Molecular markers have clarified the structure of genetic diversity in a broad range of crops. Recent developments have made whole-genome surveys and gene-targeted surveys possible, shedding light on population dynamics and on the impact of selection during domestication. Thanks to this new precision, germplasm description has gained analytical power for resolving the genetic basis of trait variation and adaptation in crops such as major cereals, chickpea, grapevine, cacao, or banana. The challenge now is to finely characterize all the facets of plant behavior in carefully chosen materials. We suggest broadening the use of ‘core reference sets’ so as to facilitate material sharing within the scientific community. [Copyright &y& Elsevier]

Abstract: A liquid chromatography–tandem mass spectrometric (LC–MS–MS) method was developed for the determination of the neurotropic–musculotropic spasmolytic agent denaverine and five of its metabolites in urine. In a first step β-glucuronidase was used to cleave glucuronides in the human urine. After that samples containing denaverine and its phase I metabolites were extracted and cleaned up using an automated solid phase extraction method. An external calibration was used. The analytes were measured employing the multiple reaction-monitoring mode (MRM). The linear dynamic range for denaverine and its five metabolites determination was demonstrated from lower limit of quantification (8.0ng/ml) to at least 500ng/ml. The presented method is suitable for pharmacokinetic or toxicokinetic studies. With the help of reference substances some additional potential metabolites could be excluded in the urine samples. To look for additional unknown metabolites the LC–MS–MS system operated on one hand in the precursor ion mode using typical product ions of denaverine and of its metabolites and on the other hand in the product ion mode using postulated protonated molecules [M +H]+. With the help of the chromatographic behaviour and typical fragment ions of the unknown metabolites it was possible to elucidate their structures. Nine until now unknown metabolites were found in the urine samples. However, without reference substances a quantification of these analytes was not possible. [Copyright &y& Elsevier]

Abstract: A liquid chromatography–tandem mass spectrometric (LC–MS–MS) method was developed and validated for the determination of the anticholinergic and antimuscarinc drug propiverine and eight of its metabolites in serum, urine, faeces and different tissue samples of rats. Samples containing propiverine and its metabolites in serum and urine and in the supernatants of faeces and tissue homogenates were extracted and cleaned up using an automated solid phase extraction (SPE) method. An external calibration was used. The analytes were measured employing the multiple reaction monitoring mode (MRM). A sufficient response over the range of 10–1000ng/ml was demonstrated. The lower limit of quantification of the nine substances was 10ng/ml. The presented method is suitable for pharmacokinetic or toxicokinetic studies. To look for additional unknown metabolites, the LC–MS–MS system operated in the precursor ion mode using typical product ions of propiverine and of its metabolites. With the help of the chromatographic behaviour and typical fragment ions of the unknown metabolites, it was possible to elucidate their structure. Five until now unknown metabolites were found in the urine and faeces samples. However, without reference substances, a quantification of these analytes was not possible. [Copyright &y& Elsevier]

The production of highly efficient single‐ and multijunction metal halide perovskite (MHP) solar cells requires careful optimization of the optical and electrical properties of these devices. Here, precise control of CH3NH3PbI3 perovskite layers is demonstrated in solar cell devices through the use of dual source coevaporation. Light absorption and device performance are tracked for incorporated MHP films ranging from ≈67 nm to ≈1.4 µm thickness and transfer‐matrix optical modeling is utilized to quantify optical losses that arise from interference effects. Based on these results, a device with 19.2% steady‐state power conversion efficiency is achieved through incorporation of a perovskite film with near‐optimum predicted thickness (≈709 nm). Significantly, a clear signature of photon reabsorption is observed in perovskite films that have the same thickness (≈709 nm) as in the optimized device. Despite the positive effect of photon recycling associated with photon reabsorption, devices with thicker (>750 nm) MHP layers exhibit poor performance owing to competing nonradiative charge recombination in a "dead‐volume" of MHP. Overall, these findings demonstrate the need for fine control over MHP thickness to achieve the highest efficiency cells, and accurate consideration of photon reabsorption, optical interference, and charge transport properties. [ABSTRACT FROM AUTHOR]

We investigate the effects of site response on source parameter estimates using earthquakes recorded by the LArge‐n Seismic Survey in Oklahoma (LASSO). While it is well known that near‐surface unconsolidated sediments can cause an apparent breakdown of earthquake self‐similarity, the influence of laterally varying site conditions remains unclear. We analyze site conditions across the 1825‐station array on a river plain within an area of 40 km by 23 km using vertical ground motions from 14 regional earthquakes. While the source radiation pattern controls P‐wave ground motions below 8 Hz, the surface geology correlates with P‐wave ground motions above 8 Hz and S‐wave ground motions at 2–21 Hz. Stations installed in alluvial sediments have vertical ground motions that can exceed three times the array median. We use the variation of ground motion of regional earthquakes across the array as a proxy for site effects. The corner frequencies and stress drops of local earthquakes (ML = 0.01–3) estimated using a standard single‐spectra approach show negative correlations with the site‐effect proxy, while the seismic moments show positive correlations. In contrast, the spectral‐ratio approach effectively shows no correlation. The overall bias is small as expected for this relatively homogeneous structure; accurate estimation of site‐related biases requires at least 30 stations. Correcting for site‐related biases reduces the standard deviations of the source parameters by less than 13% of the total variations. Remaining variations are partially associated with source directivity and model misfits— as small earthquakes can have complex ruptures. Plain Language Summary: An observed earthquake record is affected by the earthquake source, the wave path, and local site conditions, such as geology and soil properties. We need to separate these terms to accurately characterize the earthquake source. However, how local site conditions, called site effects, affect our ability to estimate accurate source parameters is not well‐understood. We use a dense array in Oklahoma on a flat river plain to quantify the influence of site effects on previously estimated source parameters, including corner frequency, seismic moment, and stress drop. The ground motions from regional earthquakes can be three times larger in certain frequency bands and time windows with spatial patterns that are related to the geology. We use the ground motions as a proxy for relative site effects. Despite the small structural changes, site effects systematically influence source parameters estimated using a standard approach of fitting individual spectra. In comparison, the spectral‐ratio approach that uses co‐located event pairs effectively removes site effects. We recommend a minimum of 30 stations to capture the site effects. In addition to the systematic site‐effect related bias, observations made by single stations are subject to large uncertainty associated with source directivity and complex rupture, even for small earthquakes. Key Points: Alluvial sediments increase vertical ground motions by up to a factor of 3.5 in the 40 km by 23 km study regionLocal site conditions in a low‐relief river plain have a systematic influence on source parameters characterized by individual spectraEven for small earthquakes, complex sources can cause large variability in source parameters [ABSTRACT FROM AUTHOR]

Analysis of Earth system dynamics in the Anthropocene requires explicitly taking into account the increasing magnitude of processes operating in human societies, their cultures, economies and technosphere and their growing feedback entanglement with those in the physical, chemical and biological systems of the planet. However, current state-of-the-art Earth system models do not represent dynamic human societies and their feedback interactions with the biogeophysical Earth system and macroeconomic integrated assessment models typically do so only with limited scope. This paper (i) proposes design principles for constructing world–Earth models (WEMs) for Earth system analysis of the Anthropocene, i.e., models of social (world)–ecological (Earth) coevolution on up to planetary scales, and (ii) presents the copan:CORE open simulation modeling framework for developing, composing and analyzing such WEMs based on the proposed principles. The framework provides a modular structure to flexibly construct and study WEMs. These can contain biophysical (e.g., carbon cycle dynamics), socio-metabolic or economic (e.g., economic growth or energy system changes), and sociocultural processes (e.g., voting on climate policies or changing social norms) and their feedback interactions, and they are based on elementary entity types, e.g., grid cells and social systems. Thereby, copan:CORE enables the epistemic flexibility needed for contributions towards Earth system analysis of the Anthropocene given the large diversity of competing theories and methodologies used for describing socio-metabolic or economic and sociocultural processes in the Earth system by various fields and schools of thought. To illustrate the capabilities of the framework, we present an exemplary and highly stylized WEM implemented in copan:CORE that illustrates how endogenizing sociocultural processes and feedbacks such as voting on climate policies based on socially learned environmental awareness could fundamentally change macroscopic model outcomes. [ABSTRACT FROM AUTHOR]

Possible future trajectories of the Earth system in the Anthropocene are determined by the increasing entanglement of processes operating in the physical, chemical and biological systems of the planet, as well as in human societies, their cultures and economies. Here, we introduce the copan:CORE open source software library that provides a framework for developing, composing and running World-Earth models, i.e., models of social-ecological co-evolution up to planetary scales. It is an object-oriented software package written in Python designed for different user roles. It allows model end users to run parallel simulations with already available and tested models. Furthermore, model composers are enabled to easily implement new models by plugging together a broad range of model components, such as opinion formation on social networks, generic carbon cycle dynamics, or simple vegetation growth. For the sake of a modular structure, each provided component specifies a meaningful yet minimal collection of closely related processes. These processes can be formulated in terms of various process types, such as ordinary differential equations, explicit or implicit functions, as well as steps or events of deterministic or stochastic fashion. In addition to the already included variety of different components in copan:CORE, model developers can extend the framework with additional components that are based on elementary entity types, i.e., grid cells, individuals and social systems, or the fundamental process taxa environment, social metabolism, and culture. To showcase possible usage we present an exemplary World-Earth model that combines a variety of model components and interactions thereof. As the framework allows a simple activation and deactivation of certain components and related processes, users can test for their specific effects on modeling results and evaluate model robustness in a controlled way. Hence, copan:CORE allows developing process-based models of global change and sustainable development in planetary social-ecological systems and thus fosters a better understanding of crucial mechanisms governing the co-evolutionary dynamics between societies and the natural environment. Due to its modular structure, the framework enhances the development and application of stylized models in Earth system science but also climatology, economics, ecology, or sociology, and allows combining them for interdisciplinary studies at the interface between different areas of expertise. [ABSTRACT FROM AUTHOR]

Dwarfing genes play an important role in improving yield and adaptability of wheat cultivars in most production environments. Understanding the allelic distribution at dwarfing loci is very important for any wheat-breeding programmes. In this study, we reported the allelic constitution at microsatellite locus Xgwm261 and the two major height-reducing genes Rht-B1 and Rht-D1 among a set of 56 bread wheat cultivars and nine landraces, based on diagnostic polymerase chain reaction assays. With respect to Rht-B1, 37% of the accessions carried the dwarfing allele Rht-B1b, while at Rht-D1, only one accession carried the dwarfing allele Rht-D1b. The allelic state at Rht8 was assayed indirectly by genotyping for the linked microsatellite locus Xgwm261. About 26% of the accessions carried the 192 bp allele (linked with Rht8 gene in some cases), whereas 35 and 12% genotypes carried 165 and 174 bp allele at the microsatellite locus Xgwm261. Cultivars released from 1980 onwards increasingly carried either Rht-B1b or Rht8. This information should allow for a more rational use of this collection for the purpose of wheat improvement in Turkey. [ABSTRACT FROM AUTHOR]

The molecular characterization of cultivated plant genepools is of foremost importance for germplasm utilization in plant breeding. However, no comprehensive genetic fingerprinting of Turkish lentil landraces existed so far. To overcome this gap, 38 lentil landraces from southeast Turkey, together with six commercial varieties, were molecularly characterized using inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) molecular markers. The ISSR analysis, performed with 14 primers, yielded 105 polymorphic bands and the AFLP analysis, carried out with six primer combinations, amplified 119 polymorphic fragments. Even though the AFLP produced more bands per primer combinations, the ISSR detected more polymorphisms. Unweighted pair-group method with arithmetic means dendrograms based on Jaccard similarities obtained from three data sets: (i) ISSR, (ii) AFLP and (iii) combined ISSR and AFLP data, were similar and separated the landraces into two main groups. Turkish lentil landraces exhibited considerable genetic diversity. One landrace from Karacadag/Diyarbakir region was significantly different from the rest of the germplasm analysed. Jaccard distances highlighted sharp differences among landraces over short geographic distances. The knowledge of regional differentiation has practical utility in the management of germplasm and in breeding programmes. [ABSTRACT FROM AUTHOR]

Since 1925, more than 100 wheat varieties were developed and released in Turkey, and many more were introduced from abroad, but no systematic analysis of their genetic diversity has been performed yet. In this research, a total of 34 domestic and foreign cultivars (12 durum and 22 bread wheats), released in Turkey between 1936 and 2000, were fingerprinted by means of five amplified fragment length polymorphism and three selective amplification of microsatellite polymorphic loci (SAMPL) primer combinations, to evaluate their genetic variation and to determine the existence of cultivar-specific bands. Among the 344 amplicons scored, 214 were polymorphic. The primer combination EACG/MAGG yielded the highest number and the primer combination SAMPL–6/M AGA produced the lowest number of polymorphic bands. Most cultivars were molecularly very similar, although a few distinct ones (the durum wheat ‘Kunduru–1149’ and the bread wheat ‘İkizce–96’) were also identified. Seven cultivar-specific markers for different bread wheat cultivars (‘Golia’, ‘Seri–82’, ‘Adana–99’, ‘Pandas’ and ‘Sertak–52’) and six cultivar-specific markers for durum wheat cv ‘Kunduru’ were observed. Our results show that genetic diversity among old and present–day wheat cultivar commonly grown in Turkey is limited. [ABSTRACT FROM AUTHOR]

The genetic relationships of A genomes of Triticum urartu (Au) and Triticum monococcum (Am) in polyploid wheats are explored and quantified by AFLP fingerprinting. Forty-one accessions of A-genome diploid wheats, 3 of AG-genome wheats, 19 of AB-genome wheats, 15 of ABD-genome wheats, and 1 of the D-genome donor Ae. tauschii have been analysed. Based on 7 AFLP primer combinations, 423 bands were identified as potentially A genome specific. The bands were reduced to 239 by eliminating those present in autoradiograms of Ae. tauschii, bands interpreted as common to all wheat genomes. Neighbour-joining analysis separates T. urartu from T. monococcum. Triticum urartu has the closest relationship to polyploid wheats. Triticum turgidum subsp. dicoccum and T. turgidum subsp. durum lines are included in tightly linked clusters. The hexaploid spelts occupy positions in the phylogenetic tree intermediate between bread wheats and T. turgidum. The AG-genome accessions cluster in a position quite distant from both diploid and other polyploid wheats. The estimates of similarity between A genomes of diploid and polyploid wheats indicate that, compared with Am, Au has around 20% higher similarity to the genomes of polyploid wheats. Triticum timo pheevii AG genome is molecularly equidistant from those of Au and Am wheats. [ABSTRACT FROM AUTHOR]

Standard cancer therapy targets tumor cells without considering possible damage on the tumor microenvironment that could impair therapy response. In rectal cancer patients we find that inflammatory cancer-associated fibroblasts (iCAFs) are associated with poor chemoradiotherapy response. Employing a murine rectal cancer model or patient-derived tumor organoids and primary stroma cells, we show that, upon irradiation, interleukin-1α (IL-1α) not only polarizes cancer-associated fibroblasts toward the inflammatory phenotype but also triggers oxidative DNA damage, thereby predisposing iCAFs to p53-mediated therapy-induced senescence, which in turn results in chemoradiotherapy resistance and disease progression. Consistently, IL-1 inhibition, prevention of iCAFs senescence, or senolytic therapy sensitizes mice to irradiation, while lower IL-1 receptor antagonist serum levels in rectal patients correlate with poor prognosis. Collectively, we unravel a critical role for iCAFs in rectal cancer therapy resistance and identify IL-1 signaling as an attractive target for stroma-repolarization and prevention of cancer-associated fibroblasts senescence. [Display omitted] • Inflammatory CAFs are associated with poor prognosis in rectal cancer • Oxidative DNA damage in iCAFs is a pre-requisite for irradiation-induced senescence • IL-1 inhibition prevents iCAF senescence upon irradiation, improving therapy response • IL-1 signaling is enhanced by low serum IL-1RA in patients with poor prognosis Nicolas et al. highlight the important role of inflammatory cancer-associated fibroblasts (iCAFs) for therapy response of rectal cancer patients. They demonstrate that IL-1-dependent signaling elevates oxidative DNA damage in iCAFs, which upon irradiation undergo senescence. This causes tissue remodeling and therapy resistance that can be overcome by inhibiting IL-1. [ABSTRACT FROM AUTHOR]

The article discusses Atomic-scale microstructure of metal halide perovskite. Topics include hybrid metal halide perovskites are highly favorable materials for efficient photovoltaic and optoelectronic applications; Atomic-resolution transmission electron microscopy is well suited to provide new insights but is challenging because of the highly beam-sensitive nature of hybrid perovskites.

Analysis of Earth system dynamics in the Anthropocene requires to explicitly take into account the increasing magnitude of processes operating in human societies, their cultures, economies and technosphere and their growing entanglement with those in the physical, chemical and biological systems of the planet. This work (i) introduces design principles for constructing World-Earth models (WEM), i.e., models of social-ecological co-evolution on up to planetary scales, and (ii) presents the copan:CORE open source software library that provides a simulation modeling framework for developing, composing and running such WEMs based on the proposed principles. copan:CORE is an object-oriented software package currently implemented in Python. It provides components of meaningful yet minimal collections of closely related processes in the Earth System that can be plugged together in order to compose and run WEMs. Developers can supplement the already existing model components with additional components that are based on elementary entity types, e.g., grid cells, or fundamental process taxa, e.g., environment or culture. To illustrate the capabilities of the framework, this paper presents a WEM example implemented in copan:CORE that combines a variety of model components and interactions thereof. Due to its modular structure, the simulation modeling framework enhances the development and application of integrated models in Earth system science but also climatology, economics, ecology, or sociology, and allows combining them for interdisciplinary studies such as risk assessment including explicitly the dynamics of human behavior and decision making. [ABSTRACT FROM AUTHOR]