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High‐relief glacial valleys shape the modern topography of the Southern Patagonian Andes, but their formation remains poorly understood. Two Miocene plutonic complexes in the Andean retroarc, the Fitz Roy (49°S) and Torres del Paine (51°S) massifs, were emplaced between 16.9–16.4 Ma and 12.6–12.4 Ma, respectively. Subduction of oceanic ridge segments initiated ca. 16 Ma at 54°S, leading to northward opening of a slab window with associated mantle upwelling. The onset of major glaciations caused drastic topographic changes since ca. 7 Ma. To constrain the respective contributions of tectonic‐mantle dynamics and fluvio‐glacial erosion to rock exhumation and landscape evolution, we perform inverse thermal modeling of a new data set of zircon and apatite (U‐Th)/He from the two massifs, complemented by apatite 4He/3He data for Torres del Paine. Our results show rapid rock exhumation recorded only in the Fitz Roy massif between 10 and 8 Ma, which we ascribe to local mantle upwelling forcing surface uplift and intensified erosion around 49°S. Both massifs record a pulse of rock exhumation between 7 and 4 Ma, which we interpret as enhanced erosion during the beginning of Patagonian glaciations. After a period of erosional and tectonic quiescence in the Pliocene, increased rock exhumation since 3–2 Ma is interpreted as the result of alpine glacial valley carving promoted by reinforced glacial‐interglacial cycles. This study highlights that glacial erosion was the main driver to rock exhumation in the Patagonian retroarc since 7 Ma, but that mantle upwelling might be a driving force to rock exhumation as well. Plain Language Summary: The isotopic system (U‐Th)/He in apatite and zircon record the ages in which a rock experiences relatively low temperatures (200–60°C) at shallow crustal depths (6–1 km). We present a new data set of low‐temperature thermochronometers for rocks of the Fitz Roy and Torres del Paine mountains in the Southern Patagonian Andes. Fast rock cooling can be forced by intensified surface erosion, and/or tectonic and mantle activity. An episode of fast cooling between 10 and 8 Ma was identified in the Fitz Roy mountains, and mantle upwelling forcing surface uplift, combined with high fluvial erosion may have caused fast rock exhumation. A regional episode of fast rock cooling between 7 and 4 Ma causing 1–3 km of exhumation in the Fitz Roy and Torres del Paine is coincident with the onset of Patagonian glaciations, which would have enhanced erosion and, thus, rock exhumation. An episode of fast rock cooling in the Quaternary is recorded in Torres del Paine rocks, interpreted as enhanced fluvio‐glacial erosion during the Plio‐Pleistocene climate transition toward faster glacial/interglacial cycles. Therefore, we were able to quantify separately the effects of tectonics and climate changes on rock exhumation, what is usually difficult due to simultaneously occurring processes. Key Points: Mantle upwelling in Southern Patagonia is the most likely mechanism forcing rock exhumation between 10 and 8 Ma in the Fitz Roy massifApatite (U‐Th)/He data reveal glacial erosion as the main driver to the exhumation of the Fitz Roy and Torres del Paine between 7 and 4 MaApatite 4He/3He data reveal intensified fluvio‐glacial erosion in Torres del Paine as a result of the Plio‐Pleistocene climate transition [ABSTRACT FROM AUTHOR]

Introduction: Left atrial (LA) low voltage areas (LVA) are a controversial target in atrial fibrillation ablation procedures. However, LVA and LA volume are good predictors of arrhythmia recurrence in ablation‐naïve patients. Their predictive value in progressively diseased pre‐ablated atria is uncertain. Methods: Consecutive patients with recurrent atrial fibrillation (AF) or atrial tachycardia (AT), who were scheduled for repeat LA ablation, were enrolled in the prospective Bernau ablation registry between 2016 and 2020. All patients received a complete LA ultrahigh‐density map before ablation. Maps were analyzed for LA size, LVA percentage and distribution. The predictive value of demographic, anatomic, and mapping variables on AF recurrence was analyzed. Results: 160 patients (50.6% male, 1.3 pre‐ablations, 60% persistent AF) with complete LA voltage maps were included. Mean follow‐up time was 16 ± 11 months. Mean recorded electrograms (EGMs) per map were 9754 ± 5808, mean LA volume was 176.1 ± 35.9 ml and mean rate of LVAs <0.5 mV was 30.6% ± 23.1%. During follow‐up recurrence rate of AF or AT >30 s was 55.6%. Patients with recurrence had a significant higher percentage of LVAs (40.0% vs. 18.8%, p <.001) but no relevant difference in LA volume (172 vs. 178 mL, p =.299). ROC curves revealed LVA as a good predictor for recurrence (AUC = 0.79, p <.001) and a cut‐off of 22% LVAs with highest sensitivity (73.0%) and specificity (71.8%). Based on this cut off, event free survival was significantly higher in the Low LVA group (p <.01). Conclusion: Total LVA percentage has a good predictive power on arrhythmia recurrence in a cohort of advanced scarred left atria in repeat procedures independent of the applied ablation strategy. Left atrial volume seems to have minor impact on the rhythm outcome in our study cohort. [ABSTRACT FROM AUTHOR]

The Anthropocene has been framed around humanity's impact on atmospheric, biologic, and near‐surface processes, such as land use and vegetation change, greenhouse gas emissions, and the above‐ground hydrologic cycle. Groundwater extraction has lowered water tables in many key aquifers but comparatively little attention has been given to the impacts in the deeper subsurface. Here, we show that fluid fluxes from the extraction and injection of fluids associated with oil and gas production and inflow of water into mines likely exceed background flow rates in deep (>500 m) groundwater systems at a global scale. Projected carbon capture and sequestration (CCS), geothermal energy production, and lithium extraction to facilitate the energy transition will require fluid production rates exceeding current oil and co‐produced water extraction. Natural analogs and geochemical modeling indicate that subsurface fluid manipulation in the Anthropocene will likely appear in the rock record. The magnitude and importance of these changes are unclear, due to a lack of understanding of how deep subsurface hydrologic and geochemical cycles and associated microbial life interact with the rest of the Earth system. Plain Language Summary: The Anthropocene is often framed in terms of changes in climate, ecosystems and land use. These have been accompanied by changes in the Earth's water cycle, including depleted groundwater storage due to pumping in many regions. The scale of anthropogenic change in the subsurface at depths beyond typical water wells has received less attention. Fluid flow rates associated with oil and gas production likely exceed natural groundwater flow rates at depths greater than 500 m. Anthropogenic impacts to this deeper zone of the Earth's subsurface are expected to increase dramatically as we look to store carbon, mine lithium from deep brines and produce geothermal energy as part of the ongoing energy transition. Key Points: Current anthropogenic fluid fluxes in the deep subsurface likely exceed background fluxesAnthropogenic fluid fluxes in the deep subsurface are expected to accelerate with the energy transitionInjection and production of fluids from the deep subsurface is expected to leave a mark on the geologic record [ABSTRACT FROM AUTHOR]

The Influence of the Physical and Chemical Properties of Hardened Cement Paste on the Fire‐induced Spalling of Concrete A number of major fire incidents in recent decades, particularly in tunnels and indoor car parks, have increased the awareness among construction designers towards the potential susceptibility of concrete to fire‐induced explosive spalling. In some fields of application, this violent breaking‐off of concrete layers may reduce the fire resistance time of fire‐exposed construction elements. The mechanisms causing explosive spalling are not yet fully understood and discussed controversially among scientists.Fire tests of concrete specimens have shown that the type of cement may have a marked influence on the susceptibility of concrete to explosive spalling. Three common characteristics of those concretes that were found to have an increasedsusceptibility of spalling were identified. For each of the three common characteristics, acorresponding hypothesis describing its possible contribution to the fire‐induced concretespalling was proposed. This second part of the article describes the experiments to verify the hypotheses using a dedicated test programme. The evaluation of the tests identified the main mechanisms by which spalling is caused. [ABSTRACT FROM AUTHOR]

The Influence of the Physical and Chemical Properties of Hardened Cement Paste on the Fire‐Induced Spalling of Concrete A number of major fire incidents in recent decades, particularly in tunnels and indoor car parks, have increased the awareness among construction designers towards the potential susceptibility of concrete to fire‐induced explosive spalling. In some fields of application, this violent breaking‐off of concrete layers may reduce the fire resistance time of fire‐exposed construction elements. The mechanisms causing explosive spalling are not yet fully understood and discussed controversially among scientists. Fire tests of concrete specimens have shown that the type of cement may have a marked influence on the susceptibility of concrete to explosive spalling. The main objectives of the experimental programme described in this article were therefore to – determine the way in which the physical and chemical properties of the hardened cement paste influence the spalling propensity of heated concrete; and in this manner – contribute to a better understanding of the mechanisms causing explosive spalling. Three common characteristics of those concretes that were found to have an increased susceptibility of spalling were identified. For each of the three common characteristics, a corresponding hypothesis describing its possible contribution to the fire‐induced concrete spalling was proposed. The first part of this article describes the tests in which the influence of the type of cement on the susceptibility of concrete to explosive spalling was investigated, as well as thethree hypotheses. Each of the three hypotheses in turn was verified through a dedicated experimental programme. The experiments to verify the hypotheses are described in the second part of this article. The evaluation of the experiments identified the main mechanisms by which spalling is caused. [ABSTRACT FROM AUTHOR]

Guanylate‐binding proteins (GBPs) are essential interferon‐γ‐activated large GTPases that play a crucial role in host defense against intracellular bacteria and parasites. While their protective functions rely on protein polymerization, our understanding of the structural intricacies of these multimerized states remains limited. To bridge this knowledge gap, we present dimer models for human GBP1 (hGBP1) and murine GBP2 and 7 (mGBP2 and mGBP7) using an integrative approach, incorporating the crystal structure of hGBP1's GTPase domain dimer, crosslinking mass spectrometry, small‐angle X‐ray scattering, protein–protein docking, and molecular dynamics simulations. Our investigation begins by comparing the protein dynamics of hGBP1, mGBP2, and mGBP7. We observe that the M/E domain in all three proteins exhibits significant mobility and hinge motion, with mGBP7 displaying a slightly less pronounced motion but greater flexibility in its GTPase domain. These dynamic distinctions can be attributed to variations in the sequences of mGBP7 and hGBP1/mGBP2, resulting in different dimerization modes. Unlike hGBP1 and its close ortholog mGBP2, which exclusively dimerize through their GTPase domains, we find that mGBP7 exhibits three equally probable alternative dimer structures. The GTPase domain of mGBP7 is only partially involved in its dimerization, primarily due to an accumulation of negative charge, allowing mGBP7 to dimerize independently of GTP. Instead, mGBP7 exhibits a strong tendency to dimerize in an antiparallel arrangement across its stalks. The results of this work go beyond the sequence–structure–function relationship, as the sequence differences in mGBP7 and mGBP2/hGBP1 do not lead to different structures, but to different protein dynamics and dimerization. The distinct GBP dimer structures are expected to encode specific functions crucial for disrupting pathogen membranes. [ABSTRACT FROM AUTHOR]

Psychological stress and traumatic brain injury (TBI) result in long‐lasting emotional and behavioral impairments in patients. So far, the interaction of psychological stress with TBI not only in the brain but also in peripheral organs is poorly understood. Herein, the impact of acute stress (AS) occurring immediately before TBI is investigated. For this, a mouse model of restraint stress and TBI was employed, and their influence on behavior and gene expression in brain regions, the hypothalamic–pituitary–adrenal (HPA) axis, and peripheral organs was analyzed. Results demonstrate that, compared to single AS or TBI exposure, mice treated with AS prior to TBI showed sex‐specific alterations in body weight, memory function, and locomotion. The induction of immediate early genes (IEGs, e.g., c‐Fos) by TBI was modulated by previous AS in several brain regions. Furthermore, IEG upregulation along the HPA axis (e.g., pituitary, adrenal glands) and other peripheral organs (e.g., heart) was modulated by AS–TBI interaction. Proteomics of plasma samples revealed proteins potentially mediating this interaction. Finally, the deletion of Atf3 diminished the TBI‐induced induction of IEGs in peripheral organs but left them largely unaltered in the brain. In summary, AS immediately before brain injury affects the brain and, to a strong degree, also responses in peripheral organs. [ABSTRACT FROM AUTHOR]

Chemistry teachers are often the only professionally trained role models for students when it comes to the safe handling of hazardous materials, equipment and chemical substances and thus have an impact beyond the classroom. In this respect, practical laboratory training of student teachers plays a key role in safe experimentation as a whole. To find out what exactly chemistry teacher students are able or should be able to do, safety‐related experimental competencies were modelled and assessed by videotaped, hands‐on performance. The results of the qualitative evaluation suggest that safety in the context of the experimental process is only possible through an interplay of several factors: Beyond the safe handling of substances and materials, safety knowledge, skills and information literacy to select and understand information in a correct way are necessary. However, fundamental to safe experimentation in the laboratory and thus later in school is an awareness of the importance of safety in the experimental process in general. [ABSTRACT FROM AUTHOR]

How subsurface microbial life changed at the bottom of the kilometers‐deep (hypo) Critical Zone in response to evolving surface conditions over geologic time is an open question. This study investigates the burial and exhumation, biodegradation, and fluid circulation history of hydrocarbon reservoirs across the Colorado Plateau as a window into the hypo‐Critical Zone. Hydrocarbon reservoirs, in the Paradox and Uinta basins, were deeply buried starting ca. 100 to 60 Ma, reaching temperatures >80–140°C, likely sterilizing microbial communities present since the deposition of sediments. High salinities associated with evaporites may have further limited microbial activity. Upward migration of hydrocarbons from shale source rocks into shallower reservoirs during maximum burial set the stage for microbial re‐introduction by creating organic‐rich "hot spots." Denudation related to the incision of the Colorado River over the past few million years brought reservoirs closer to the surface under cooler temperatures, enhanced deep meteoric water circulation and flushing of saline fluids, and likely re‐inoculated more permeable sediments up to several km depth. Modern‐ to paleo‐hydrocarbon reservoirs show molecular and isotopic evidence of anaerobic oxidation of hydrocarbons coupled to bacterial sulfate reduction in areas with relatively high SO4‐fluxes. Anaerobic oil biodegradation rates are high enough to explain the removal of at least some portion of postulated "supergiant oil fields" across the Colorado Plateau by microbial activity over the past several million years. Results from this study help constrain the lower limits of the hypo‐Critical Zone and how it evolved over geologic time, in response to changing geologic, hydrologic, and biologic forcings. Plain Language Summary: This study investigates the dynamic geologic, hydrologic, and biological history of hydrocarbon reservoirs across the Colorado Plateau to gain insights into how the lower boundaries for microbial life evolved in response to changes in earth surface conditions. Microbial communities at depth were likely sterilized in the geologic past when sediments were deeply buried, reaching temperatures beyond the limits for microbial life. Generation and upward migration of oil and gas, during this time, set the stage for later re‐introduction of microbial communities that degrade hydrocarbons. Recent down‐cutting of the Colorado River and erosion of the Colorado Plateau, over the past few million years, brought hydrocarbon reservoirs closer to the surface, at lower temperatures and in contact with circulating groundwater. Associated transport of microbial communities and solutes drove the biodegradation of oil in more permeable reservoirs. This type of biological activity could have been responsible for the removal of ancient oil fields across the Colorado Plateau. The integrated approach used in this study could be applied to other crustal environments to unravel the co‐evolution of microbe‐rock‐fluid systems at the bottom of the deep biosphere. Key Points: Sediments at depth across the Colorado Plateau were likely sterilized during maximum burial and hydrocarbon generationHydrocarbon‐containing sediments were re‐inoculated during recent denudation, meteoric water circulation, and flushing of saline fluidsSome portion of hydrocarbons were removed via anaerobic oxidation coupled to bacterial sulfate reduction in areas of sulfate influx [ABSTRACT FROM AUTHOR]

The 2018 European Union (EU) approved weekly and monthly subcutaneous buprenorphine depot injection (BUP‐XR), for opioid substitution medication proved to offer some specific treatment benefits. The present study examines the process of switching from buprenorphine sublingual tablets (BUP‐SL) to BUP‐XR from a patient's point of view. In total, nine patients were surveyed by means of an open‐answer questionnaire regarding course and side effects of the medication switch. Six of these patients were surveyed in more detail under BUP‐SL, as well as 4 and 16 weeks after the switch to BUP‐XR by means of a test battery of questions on socio‐demography, withdrawal symptoms, craving, physical well‐being, treatment satisfaction and concomitant use of illegal substances. Patients reported significant worse physical well‐being and lower treatment satisfaction in 4 weeks compared with 16 weeks after the medication switch to the BUP‐XR. Furthermore, they reported significant more frequent co‐use of illicit drugs, worse physical well‐being, lower treatment satisfaction and more craving experience 4 weeks after the switch compared with the treatment under BUP‐SL. Patients 16 weeks under BUP‐XR reported significant more illicit co‐use and lower treatment satisfaction compared with patients under BUP‐SL. Connections between therapy dissatisfaction, physical discomfort, experienced craving and drug co‐consumption were discovered. In the first weeks after the medication switch, patients experience potentially distressing symptoms, which, however, seem to diminish over time. Close supervision and comprehensive patient education on possible burdens of the medication switch to the BUP‐XR might prevent unfavourable treatment courses and premature therapy dropouts. [ABSTRACT FROM AUTHOR]

Detection of tumor progression in patients with glioblastoma remains a major challenge. Extracellular vesicles (EVs) are potential biomarkers and can be detected in the blood of patients with glioblastoma. In our study, we evaluated the potential of serum‐derived EVs from glioblastoma patients to serve as biomarker for tumor progression. EVs from serum of glioblastoma patients and healthy volunteers were separated by size exclusion chromatography and ultracentrifugation. EV markers were defined by using a proximity‐extension assay and bead‐based flow cytometry. Tumor progression was defined according to modified RANO criteria. EVs from the serum of glioblastoma patients (n = 67) showed an upregulation of CD29, CD44, CD81, CD146, C1QA and histone H3 as compared to serum EVs from healthy volunteers (P value range: <.0001 to.08). For two independent cohorts of glioblastoma patients, we noted upregulation of C1QA, CD44 and histone H3 upon tumor progression, but not in patients with stable disease. In a multivariable logistic regression analysis, a combination of CD29, CD44, CD81, C1QA and histone H3 correlated with RANO‐defined tumor progression with an AUC of 0.76. Measurement of CD29, CD44, CD81, C1QA and histone H3 in serum‐derived EVs of glioblastoma patients, along with standard MRI assessment, has the potential to improve detection of true tumor progression and thus could be a useful biomarker for clinical decision making. [ABSTRACT FROM AUTHOR]

The subduction of bathymetric highs, such as aseismic ridges, leads to far‐reaching changes in the dynamics of subduction zones with increased plate coupling and deformation in the upper plate. Subduction of the submarine Carnegie Ridge on the Nazca Plate has fundamentally impacted late Cenozoic magmatism and tectonic activity in the northern Andes. However, the timing of onset of Carnegie Ridge subduction has been a matter of debate. Time‐temperature inverse modeling of new thermochronological data from the Western Cordillera of Ecuador reveals two phases of cooling separated by isothermal conditions. The first cooling phase postdates early and middle Miocene magmatism in the Western Cordillera and is attributed to post‐magmatic thermal relaxation. The second cooling phase started after 6 Ma. Inferred to record the onset of tectonically controlled rock uplift and exhumation in the Western Cordillera, this phase is coeval with the last cooling phase recorded in the Eastern Cordillera. Based on these findings, we suggest that the onset of subduction of the Carnegie Ridge at ∼6–5 Ma increased plate coupling at the subduction interface, promoting shortening, regional rock uplift, and exhumation in the northern Andes. Overall, our results highlight the essential role of bathymetric highs in driving regional upper‐plate deformation at non‐collisional convergent plate margins. Plain Language Summary: Topographic growth and morphology of the Andes have been influenced by subduction processes, tectonic inheritance, and climate. Here, we investigate the role of subduction of high topography on the ocean floor in driving deformation in the upper plate at the Nazca‐South America ocean‐continent plate margin. The subduction of the Carnegie Ridge, a linear, topographically high sector on the Nazca Plate, has impacted magmatism and deformation processes in the Ecuadorian Andes. However, the timing of onset of ridge subduction is debated. We employed radioisotopic dating techniques to evaluate the uplift of the Andes. These techniques record the cooling of rocks as mountain ranges are uplifted and eroded. The thermal histories of rocks from the Western Cordillera in Ecuador reveal two distinct cooling phases. The first cooling phase occurred shortly after Miocene magmatic bodies were emplaced in the Western Cordillera. The second cooling phase began at ∼6–5 Ma, coeval with the last cooling phase in the Eastern Cordillera. We attribute this cooling phase to the onset of uplift and erosion in the Western Cordillera. Based on these findings, we suggest that the onset of subduction of the Carnegie Ridge increased plate coupling and promoted shortening and rock uplift in the northern Andes. Key Points: Thermochronological data reveal two cooling phases in the Western Cordillera of Ecuador, during the Miocene and after 6 MaThe onset of cooling at 6 Ma was associated with shortening, rock uplift, and exhumation in the Western CordilleraMio‐Pliocene exhumation was related to stronger coupling of the subduction interface due to the initial subduction of the Carnegie Ridge [ABSTRACT FROM AUTHOR]

Extensive regions of yellow and white ("bleached") sandstones within the terrestrial Jurassic red bed deposits of the Colorado Plateau reflect widespread interaction with subsurface reduced fluids which resulted in the dissolution of iron‐oxide grain coatings. Reduced fluids such as hydrocarbons, CO2, and organic acids have been proposed as bleaching agents. In this study, we characterize an altered section of the Slick Rock member of the Jurassic Entrada Sandstone that exposes bleached sandstone with bitumen‐saturated pore spaces. We observe differences in texture, porosity, mineralogy, and geochemistry between red, pink, yellow, and gray facies. In the bleached yellow facies we observe quartz overgrowths, partially dissolved K‐feldspar, calcite cement, fine‐grained illite, TiO2‐minerals, and pyrite concretions. Clay mineral content is highest at the margins of the bleached section. Fe2O3 concentrations are reduced up to 3× from the red to gray facies but enriched up to 50× in iron‐oxide concretions. Metals such as Zn, Pb, and rare‐earth elements are significantly enriched in the concretions. Supported by a batch geochemical model, we conclude the interaction of red sandstones with reduced hydrocarbon‐bearing fluids caused iron‐oxide and K‐feldspar dissolution, and precipitation of quartz, calcite, clay, and pyrite. Localized redistribution of iron into concretions can account for most of the iron removed during bleaching. Pyrite and carbonate stable isotopic data suggest the hydrocarbons were sourced from the Pennsylvanian Paradox Formation. Bitumen in pore spaces and pyrite precipitation formed a reductant trap required to produce Cu, U, and V enrichment in all altered facies by younger, oxidized saline brines. Plain Language Summary: Thin coatings of iron‐oxide on grains give sandstones deposited during the Jurassic Period on the Colorado Plateau a characteristic red pigment. Vast areas of yellow and white ("bleached") colored sandstones within these red bed deposits represent widespread interaction with fluids such as hydrocarbons, carbon dioxide, and organic acids, which dissolved the iron‐oxide grain coatings. These altered sandstones can provide useful information on hydrocarbons or carbon dioxide plume migration pathways, relevant to long‐term geological storage of carbon dioxide. In this study, we characterize a section of the Jurassic Entrada Sandstone that exposes a bleached sandstone with hydrocarbon‐saturated pore spaces. By comparing the unaltered red sandstones to the bleached sandstones at the study site, we find that hydrocarbon‐bearing fluids dissolved minerals like iron‐oxide and K‐feldspar, and precipitated minerals such as quartz, calcite, clay, and pyrite. The iron that was dissolved has been locally redistributed into small, dense spherical accumulations (concretions) of pyrite and iron‐oxide. These accumulations also contain significant enrichment of other metals such as lead, zinc, and rare‐earth elements compared to the sandstones. The presence of pyrite and hydrocarbons caused enrichment of copper, uranium, and vanadium in all altered sandstone and concretions compared to the unaltered red sandstone by the later flow of oxidized saline brines. Key Points: The studied bleached section of Jurassic sandstones in the Paradox Basin reflects interaction with migrating hydrocarbonsAbundant bitumen supports reduction by hydrocarbons that redistributed iron and high‐field strength elements into localized concretionsCompositional and mineralogic gradients across the bleached sandstone compare well with a batch geochemical model of hydrocarbon migration [ABSTRACT FROM AUTHOR]

A central implication of scientific literacy is the ability of students to participate in discourses and decision‐making processes concerning societal challenges, such as climate change, on the basis of their acquired scientific knowledge. In order to provide them with corresponding competences it is necessary that teachers themselves are enabled to participate in matters of social importance and this implies acquiring corresponding subject‐matter knowledge as well as the ability to evaluate various sources of data and information. In addition, chemistry teachers must be able to transform the societal challenges and problems into teaching practice. To this end, a course for preservice chemistry teachers was designed, that focused on discourses of emissions of carbon and nitrogen oxides. In a qualitative setting, the developments of preservice chemistry teachers were explored during the course. [ABSTRACT FROM AUTHOR]

Krypton‐81 dating provides new insights into the timing, mechanisms, and extent of meteoric flushing versus retention of saline fluids in the subsurface in response to changes in geologic and/or climatic forcings over 50 ka to 1.2 Ma year timescales. Remnant Paleozoic seawater‐derived brines associated with evaporites in the Paradox Basin, Colorado Plateau, are beyond the 81Kr dating range (>1.2 Ma) and have likely been preserved due to negative fluid buoyancy and low permeability. 81Kr dating of formation waters above the evaporites indicates topographically‐driven meteoric recharge and salt dissolution since the Late Pleistocene (0.03–0.8 Ma). Formation waters below the evaporites (up to 3 km depth), in basal aquifers, contain relatively young meteoric water components (0.4–1.1 Ma based on 81Kr) that partially flushed remnant brines and dissolved evaporites. We demonstrate that recent, rapid denudation of the Colorado Plateau (<4–10 Ma) activated deep, basinal‐scale flow systems as recorded in 81Kr groundwater age distributions. Plain Language Summary: Landscape changes over geological time alter hydraulic gradients and the presence or absence of near‐surface confining units, which drive the evolution of subsurface flow systems. However, our understanding of the time required for groundwater flow systems to respond to geological processes, such as shifts in topography, stratigraphy, and permeability structures, is still limited. This study uses krypton‐81 dating to constrain the age of meteoric waters in the Paradox Basin in the Colorado Plateau and constrain the timing of groundwater recharge into basinal aquifers. We discovered that rapid, widespread erosion and incision in the Colorado Plateau in the last 10 Ma activated deep meteoric circulation, partially flushing residual ancient seawater‐derived brines from aquifers above and below thick, evaporite confining units and dissolving salt. Krypton‐81 dating may provide insights into timescales and drivers of subsurface fluid flow and connectivity with the near‐surface in other environments. Key Points: Meteoric waters up to 3 km in basinal aquifers are <1.1 MaRecent, rapid denudation of the Colorado Plateau enabled deep circulation of meteoric water and flushing of connate brinesKrypton‐81 dating can illuminate the timescales and extent of meteoric circulation in response to geologic and/or climatic forcings [ABSTRACT FROM AUTHOR]

An almost forgotten acid−base theory is the definition by Soviet chemist Mikhail Usanovich, which was developed in the late 1930s, at about the same time as Lewis′s much betterknown definition. His very broad conception demonstrated parallels between proton and electron transfers in a variety of chemical reactions, long before "the principle of donors and acceptors" gained a prominent role in German chemistry education. This article portrays not only the Usanovich definition itself, but also demonstrates its value as a historical context for teaching nature of science (NOS). Furthermore, the corresponding results of a study involving teacher‐students are presented. [ABSTRACT FROM AUTHOR]

Like many carnivore species, European wildcats (Felis silvestris) have suffered severe anthropogenic population declines in the past, resulting in a strong population bottleneck at the beginning of the 20th century. In Germany, the species has managed to survive its near extinction in small isolated areas and is currently recolonizing former habitats owing to legal protection and concerted conservation efforts. Here, we SNP‐genotyped and mtDNA‐sequenced 56 historical and 650 contemporary samples to assess the impact of massive persecution on genetic diversity, population structure, and hybridization dynamics of wildcats. Spatiotemporal analyses suggest that the presumed postglacial differentiation between two genetically distinct metapopulations in Germany is in fact the result of the anthropogenic bottleneck followed by re‐expansion from few secluded refugia. We found that, despite the bottleneck, populations experienced no severe genetic erosion, nor suffered from elevated inbreeding or showed signs of increased hybridization with domestic cats. Our findings have significant implications for current wildcat conservation strategies, as the data analyses show that the two presently recognized wildcat population clusters should be treated as a single conservation unit. Although current populations appear under no imminent threat from genetic factors, fostering connectivity through the implementation of forest corridors will facilitate the preservation of genetic diversity and promote long‐term viability. The present study documents how museum collections can be used as essential resource for assessing long‐term anthropogenic effects on natural populations, for example, regarding population structure and the delineation of appropriate conservation units, potentially informing todays' species conservation. [ABSTRACT FROM AUTHOR]

According to the concept of Scientific Literacy, students should be empowered to recognise scientific issues in order to make critical decisions by using scientific knowledge. However, students rarely use scientific decision‐making criteria in everyday life. Therefore, they need to be supported in order to be able to link those situations to appropriate content in chemistry classes. For this purpose, the "decision diary" tool was developed. It aims at making them aware of their everyday decision situations with scientific issues as well as enable them to identify decision situations in which they are willing to adopt new evidence‐based decision strategies. Thus, the objective of the study concerns the question to what extent the decision diary is an adequate instrument to identify decision situations in everyday life. [ABSTRACT FROM AUTHOR]

Fe‐ and Mn‐oxides are common secondary minerals in faults, fractures, and veins and potentially record information about the timing of fluid movement through their host rocks. These phases are difficult to date by most radioisotopic techniques, but relatively high concentrations of U and Th make the (U‐Th)/He system a promising approach. We present new petrographic, geochronologic and thermochronologic analyses of secondary oxides and associated minerals from fault zones and fractures in southeastern Arizona. We use these phases in attempt to constrain the timing of fluid flow and their relationship to magmatic, tectonic, or other regional processes. In the shallowly exhumed Galiuro Mountains, Fe‐oxide (U‐Th)/He dates correspond to host‐rock crystallization and magmatic intrusions from ca. 1.6 to 1.1 Ga. Step‐heating 4He/3He experiments and polydomain diffusion modeling of 3He release spectra on these samples are consistent with a crystallite size control on He diffusivity, and little fractional loss of radiogenic He since formation in coarse‐grained hematite, but large losses from fine‐grained Mn‐oxide. In contrast to Proterozoic dates, Fe‐ and Mn‐oxides from the Catalina‐Rincon and Pinaleño metamorphic core complexes are exclusively Cenozoic, with dates clustering at ca. 24, 15, and 9 Ma, which represent distinct cooling or fluid‐flow episodes during punctuated periods of normal faulting. Finally, a subset of Fe‐oxides yield dates of ca. 5 Ma to 6 ka and display either pseudomorphic cubic forms consistent with oxidative retrogression of original pyrite or magnetite, or fine‐grained botryoidal morphologies that we interpret to represent approximate ages of recrystallization or pseudomorphic replacement at shallow depths. Plain Language Summary: (U‐Th)/He dating is increasingly applied to secondary Fe‐ and Mn‐oxide minerals in an attempt to understand the timing of fluid‐rock reactions associated with magmatic intrusions, fault activity, or other forcings. However, accurate interpretations of secondary oxide thermochronology data requires consideration of potential complications that can lead to multiple interpretations. Here we present (U‐Th)/He and 4He/3He thermochronologic analyses along with chemical and textural observations and provide a geologic context for secondary Fe‐ and Mn‐oxides from southeastern Arizona, in an attempt to better understand how the data relate to geologic processes. Many of these minerals formed and/or cooled in fault zones and fractures at times associated with magmatic or tectonic activity, but some were also recrystallized or pseudomorphically replaced by later fluid‐rock reactions. We also provide evidence that He diffusivity is governed by crystal sizes, and that crystal shape and chemical composition should be considered when interpreting (U‐Th)/He data of Fe‐ and Mn‐oxides. Key Points: Step heating experiments and He diffusion modeling of Fe‐ and Mn‐oxides are consistent with a grain size control on He diffusivityFe‐ and Mn‐oxide (U‐Th)/He dates from southeastern Arizona are consistent with Proterozoic‐Cenozoic magmatic and tectonic eventsPetrographic and spectroscopic characterizations of Fe‐ and Mn‐oxides help provide context for (U‐Th)/He data interpretation [ABSTRACT FROM AUTHOR]

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From an epistemological point of view, tentativeness is an important feature of scientific knowledge. With regard to current debates on "fake science", it becomes also significant within science education. The article provides a proposal for clarifying the term. In addition, results of two qualitative studies are presented. They reveal that most preservice chemistry teachers held inconsistent views on tentativeness, which are furthermore resistant to change. In order to promote a more adequate understanding, it is necessary to deal intensively with the tentative nature of science as well as to address the durability and reliability of well‐supported scientific knowledge. Further approaches to promote an adequate and functional understanding are presented and discussed. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Strained ring systems have gained considerable importance over the last few years for their implication in natural product syntheses or in drug discovery programs. We present herein a recollection of our work on the construction and functionalization of unsaturated four‐membered carbo‐ and heterocycles in the context of the literature, as well as their applications in further reactions. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims/Introduction: Despite its major clinical impact, distal symmetric polyneuropathy remains frequently undiagnosed and undertreated in clinical practice. We previously reported in the PROTECT Study that 70% of type 2 diabetes patients with distal symmetric polyneuropathy were unaware of having the latter condition. Materials and Methods: In the present follow up after 2.5 ± 0.7 years, 122 and 85 participants with and without type 2 diabetes, respectively, completed questionnaires to obtain information about the further course of disease and its management. Results: At follow up, 49 and 48% of the respondents with type 2 diabetes and without diabetes, respectively, reported that the intensity of paresthesia or numbness in the feet increased, whereas for burning and pain in the feet the corresponding percentages were 56 and 61%. However, 33 and 40% of the respondents with type 2 diabetes and without diabetes, respectively, reporting neuropathic symptoms at follow up did not receive any pharmacotherapy. Pharmacotherapy of neuropathic symptoms at follow up among participants with type 2 diabetes and without diabetes included mainly World Health Organization Step 1 analgesics (17% each; excluding acetylsalicylic acid), pregabalin/gabapentin (20 and 12%), vitamin B complex (13 and 22%), benfotiamine (13 and 2%), opioids (7 and 12%), antidepressants (4 and 5%) and α‐lipoic acid (4 and 2%). Conclusions: These findings point to insufficient care, inadequate treatment adherence or limited efficacy of treatments in patients with polyneuropathy, suggesting that effective measures should be implemented to correct these healthcare deficits. [ABSTRACT FROM AUTHOR]

Thiete dioxide units have been employed as a template for further functionalization through C−H activation strategies. Using simple thiete dioxide building blocks, a new library of axially chiral molecules has been synthesized that owe their stability to electrostatic interactions in the solid state. Similar starting materials were further engaged in the formation of cyclic trimeric structures, opening the pathway to unprecedented macrocyclic ring systems. [ABSTRACT FROM AUTHOR]

The genomic era has led to an unprecedented increase in the availability of genome‐wide data for a broad range of taxa. Wildlife management strives to make use of these vast resources to enable refined genetic assessments that enhance biodiversity conservation. However, as new genomic platforms emerge, problems remain in adapting the usually complex approaches for genotyping of noninvasively collected wildlife samples. Here, we provide practical guidelines for the standardized development of reduced single nucleotide polymorphism (SNP) panels applicable for microfluidic genotyping of degraded DNA samples, such as faeces or hairs. We demonstrate how microfluidic SNP panels can be optimized to efficiently monitor European wildcat (Felis silvestris S.) populations. We show how panels can be set up in a modular fashion to accommodate informative markers for relevant population genetics questions, such as individual identification, hybridization assessment and the detection of population structure. We discuss various aspects regarding the implementation of reduced SNP panels and provide a framework that will allow both molecular ecologists and practitioners to help bridge the gap between genomics and applied wildlife conservation. [ABSTRACT FROM AUTHOR]

The expanding field of extracellular vesicle (EV) research needs reproducible and accurate methods to characterize single EVs. Nanoparticle Tracking Analysis (NTA) is commonly used to determine EV concentration and diameter. As the EV field is lacking methods to easily confirm and validate NTA data, questioning the reliability of measurements remains highly important. In this regard, a comparison addressing measurement quality between different NTA devices such as Malvern's NanoSight NS300 or Particle Metrix' ZetaView has not yet been conducted. To evaluate the accuracy and repeatability of size and concentration determinations of both devices, we employed comparative methods including transmission electron microscopy (TEM) and single particle interferometric reflectance imaging sensing (SP-IRIS) by ExoView. Multiple test measurements with nanospheres, liposomes and ultracentrifuged EVs from human serum and cell culture supernatant were performed. Additionally, serial dilutions and freeze-thaw cycle-dependent EV decrease were measured to determine the robustness of each system. Strikingly, NanoSight NS300 exhibited a 2.0–2.1-fold overestimation of polystyrene and silica nanosphere concentration. By measuring serial dilutions of EV samples, we demonstrated higher accuracy in concentration determination by ZetaView (% BIAS range: 2.7–8.5) in comparison with NanoSight NS300 (% BIAS range: 32.9–36.8). The concentration measurements by ZetaView were also more precise (% CV range: 0.0–4.7) than measurements by NanoSight NS300 (% CV range: 5.4–10.7). On the contrary, quantitative TEM imaging indicated more accurate EV sizing by NanoSight NS300 (% DTEM range: 79.5–134.3) compared to ZetaView (% DTEM range: 111.8–205.7), while being equally repeatable (NanoSight NS300% CV range: 0.8–6.7; ZetaView: 1.4–7.8). However, both devices failed to report a peak EV diameter below 60 nm compared to TEM and SP-IRIS. Taken together, NTA devices differ strongly in their hardware and software affecting measuring results. ZetaView provided a more accurate and repeatable depiction of EV concentration, whereas NanoSight NS300 supplied size measurements of higher resolution. [ABSTRACT FROM AUTHOR]

Background and Purpose: Aerobic glycolysis is a unique feature of tumour cells that entails several advantages for cancer progression such as resistance to apoptosis. The low MW compound, dichloroacetate, is a pyruvate dehydrogenase kinase inhibitor, which restores oxidative phosphorylation and induces apoptosis in a variety of cancer entities. However, its therapeutic effectiveness is limited by resistance mechanisms. This study aimed to examine the role of the anti-apoptotic hyaluronan (HA) matrix in this context and to identify a potential add-on treatment option to overcome this limitation.Experimental Approach: The metabolic connection between dichloroacetate treatment and HA matrix augmentation was analysed in vitro by quantitative PCR and affinity cytochemistry. Metabolic pathways were analysed using Seahorse, HPLC, fluorophore-assisted carbohydrate electrophoresis, colourimetry, immunoblots, and immunochemistry. The effects of combining dichloroacetate with the HA synthesis inhibitor 4-methylumbelliferone was evaluated in 2D and 3D cell cultures and in a nude mouse tumour xenograft regression model by immunoblot, immunochemistry, and FACS analysis.Key Results: Mitochondrial reactivation induced by dichloroacetate metabolically activated HA synthesis by augmenting precursors as well as O-GlcNAcylation. This process was blocked by 4-methylumbelliferone, resulting in enhanced anti-tumour efficacy in 2D and 3D cell culture and in a nude mouse tumour xenograft regression model.Conclusions and Implications: The HA rich tumour micro-environment represents a metabolic factor contributing to chemotherapy resistance. HA synthesis inhibition exhibited pronounced synergistic actions with dichloroacetate treatment on oesophageal tumour cell proliferation and survival in vitro and in vivo suggesting the combination of these two strategies is an effective anticancer therapy. [ABSTRACT FROM AUTHOR]

Copyright of Chemkon - Chemie Konkret is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

On the occasion of the Ecological Society of America's centennial, we sought to learn which ecological concepts members value in terms of their utility. This required defining 'concept,' and selecting concepts from current ecology textbooks that might arguably belong to a normative set. All ESA members were invited to participate in an online survey in October 2014 in which they rated 70, randomly selected concepts (out of a total set of 131) in terms of utility. Alternative to rating, respondents could mark the concept as unfamiliar. Respondents were also able list concepts that were important to them that were not encountered in the survey. Fifteen percent (1324) of the ESA membership participated in the survey. Of these, 89% were addressed in North America, 62% were male, 77% held Ph.D. degrees, 67% were involved in academia through employment or as students, and about one-half of the total were divided between community and ecosystem ecology domains of interest. The 10 highest ranked concepts (in descending order) for utility were scales (small, local, regional, global, etc.), ecosystem, habitat, species, disturbance/perturbation, organism, population, community, competition, and species life history. The 10 lowest ranked concepts (in descending order) for utility were Lotka-Volterra predator-prey/competition models, Allee effect, nutrient spiraling, character displacement, doubling time, climax, Hardy-Weinberg equation, red queen hypothesis, chemoautotroph/chemoautotrophy, and mimicry. Respondents entered 2800 terms not encountered in the survey. After parsing for concepts missed due to the survey's random presentation process, for semantic redundancy and for terms deemed non-concepts, 119 candidate concepts emerged. Many of these deserve consideration for inclusion in a normative set and introduction in textbooks. This research provides a well-considered definition of 'concept,' a basis for defining a normative set of concepts expected to be known to all ecologists, and a measure of familiarity but, more importantly, a measure of usage by contemporary ecologists who were members of ESA. These results help us to understand ourselves and our science, to better teach ecology, to guide the initiatives of the collective ecological community, and to further explore the extent and intellectual structure of the principal concepts by which ecologists pursue their work. [ABSTRACT FROM AUTHOR]

Summary: Background: After partial resection of the thyroid gland, a second operation referred to as "completion thyroidectomy" may be required if histopathological analysis indicates the presence of differentiated thyroid cancer (DTC). Although there is little evidence, it is assumed that the time point of completion thyroidectomy is not critical for oncological prognosis of patients with DTC. We assessed whether patients with total thyroidectomy (TTx) in a two‐step procedure have an equal long‐term prognosis with regard to disease‐specific survival (DSS) compared to patients immediately undergoing total thyroidectomy in a one‐step procedure. Methods: A database study using the Würzburg thyroid cancer database with 2258 patients with pT1a‐pT4b tumours DTC who were operated between 1980 and 2016 was carried out. Results: A total of 277 patients with papillary microcarcinoma pT1aN0M0 were treated by hemithyroidectomy. TTx as one‐step procedure was performed in 1114 patients compared to 867 with TTx as a two‐step procedure. Patients with papillary thyroid cancer more frequently had a TTx as one‐step procedure than follicular thyroid cancer patients (59.4% vs 47%; P < 0.001). Compared to a one‐step thyroidectomy, overall complication rate was not different compared to patients undergoing a single operation. Multivariate analysis showed that the presence of distant metastases, T‐stage and age at diagnosis were the only independent determinants for DTC‐specific survival, regardless of a one‐ or two‐time thyroidectomy. Conclusion: The present study on the largest of such patient collectives provides evidence that a delayed completion operation does not affect DSS in DTC, nor does it lead to a significant increase in complication rates. [ABSTRACT FROM AUTHOR]

Scientific literacy implies an adequate understanding of central notions which characterize scientific reasoning. Nature of Science studies have lead to a general consensus of what experiments, models, theories and laws imply at school. They do not take into account how these terms are handled in recent domain‐specific theory and research. In order to come to a closer understanding we analyzed domain‐specific literature and conducted a survey into the notions of these terms by interviewing experts of the science subjects and mathematics. The results of literature analysis reveal differences in the meaning of the terms between subjects. Moreover, experts show serious inconsistencies in using the terms. The results will be presented in this paper and can be used as a starting point to draw conclusions for science teacher education. [ABSTRACT FROM AUTHOR]

Here, we document a detailed characterisation of two zircon gemstones, GZ7 and GZ8. Both stones had the same mass at 19.2 carats (3.84 g) each; both came from placer deposits in the Ratnapura district, Sri Lanka. The U‐Pb data are in both cases concordant within the uncertainties of decay constants and yield weighted mean 206Pb/238U ages (95% confidence uncertainty) of 530.26 Ma ± 0.05 Ma (GZ7) and 543.92 Ma ± 0.06 Ma (GZ8). Neither GZ7 nor GZ8 have been subjected to any gem enhancement by heating. Structure‐related parameters correspond well with the calculated alpha doses of 1.48 × 1018 g−1 (GZ7) and 2.53 × 1018 g−1 (GZ8), respectively, and the (U‐Th)/He ages of 438 Ma ± 3 Ma (2s) for GZ7 and 426 Ma ± 9 Ma (2s) for GZ8 are typical of unheated zircon from Sri Lanka. The mean U mass fractions are 680 μg g−1 (GZ7) and 1305 μg g−1 (GZ8). The two zircon samples are proposed as reference materials for SIMS (secondary ion mass spectrometry) U‐Pb geochronology. In addition, GZ7 (Ti mass fractions 25.08 μg g−1 ± 0.18 μg g−1; 95% confidence uncertainty) may prove useful as reference material for Ti‐in‐zircon temperature estimates. Key Points: We document a detailed characterisation of the Sri Lankan zircon gemstones GZ7 and GZ8 and propose them as SIMS U‐Pb reference materials. Both specimens have high mean U mass fractions and concordant Cambrian (GZ7) and Ediacaran (GZ8) U‐Pb ages. In addition, GZ7 is proposed as a reference material for Ti‐in‐zircon temperature estimates. [ABSTRACT FROM AUTHOR]

In Nevada and Utah, the Cordilleran orogen underwent a protracted Cenozoic transition to an extensional setting. However, the geodynamic processes that controlled this transition are poorly understood, in part because the space‐time patterns of extension are not known in many areas. Localities of pre‐Neogene extension have the potential to elucidate the dynamics of the Cordilleran crust during the final stages of subduction. Here we present data that constrain the timing of extension in the Grant Range in eastern Nevada, which was deformed by a low‐angle normal fault system. We present temperature‐time histories of eight granite samples exhumed by this fault system, constrained by muscovite 40Ar/39Ar multi‐diffusion domain modeling and fission track and (U‐Th)/He ages from zircon and apatite. These data demonstrate rapid cooling (20–35 °C/Myr) from 350–425 to 25–50 °C between 28–31 and 15–19 Ma. The fault system accommodated ~24 km of extension (~115%), and exhumed the granite samples from 7–9 km depths to the near‐surface. Rapid Oligocene‐early Miocene cooling is interpreted to date the duration of motion on the fault system, and defines an extension rate of 1.5–2.6 km/Myr. This was one of the most significant fault systems active during an episode of spatially distributed late Eocene‐Oligocene extension, which overlaps temporally with volcanism generated by slab rollback. Reduced interplate coupling that accompanied slab rollback is interpreted as the primary driver of extension of the Cordilleran plateau during the final stages of subduction. This supports a scenario of orogenic collapse that proceeded in distinct episodes that were initiated by external geodynamic events. Key Points: The Grant Range detachment system accommodated 24 km of extension (115%) between 31 and 15 Ma and was a significant syn‐rollback fault systemDecreased interplate coupling during slab rollback likely drove the earliest episode of distributed extension in the Cordilleran plateauMuscovite 40Ar/39Ar multi‐diffusion domain modeling is effective for constraining the cooling histories of rocks between ~425 and 250 °C [ABSTRACT FROM AUTHOR]

Many regions central to our understanding of tectonics and landscape evolution are active or ancient magmatic terranes, and robust interpretation of low‐temperature thermochronologic ages in these settings requires careful attention to the drivers of rock heating and cooling, including magmatism. However, we currently lack a quantitative framework for evaluating the potential role of magmatic cooling—that is, post‐magmatic thermal relaxation—in shaping cooling age patterns in regions with a history of intrusive magmatism. Here we use analytical approximations and numerical models to characterize how low‐temperature thermochronometers document cooling inside and around plutons in steadily exhuming environments. Our models predict that the thermal field a pluton intrudes into, specifically the ambient temperatures relative to the closure temperature of a given thermochronometer, is as important as the pluton size and temperature in controlling the pattern and extent of thermochronometer resetting in the country rocks around a pluton. We identify one advective and several conductive timescales that govern the relationship between the crystallization and cooling ages inside a pluton. In synthetic vertical age‐elevation relationships (AERs), resetting next to plutons results in changes in AER slope that could be misinterpreted as past changes in exhumation rate if the history of magmatism is not accounted for. Finally, we find that large midcrustal plutons, such as those emplaced at ~10–15‐km depth, can reset the low‐temperature thermochronometers far above them in the upper crust—a result with considerable consequences for thermochronology in arcs and regions with a history of magmatic activity that may not have a surface expression. Key Points: Intrusive magmatism may produce important first‐order effects on patterns of low‐temperature thermochronometer coolingAnalytical approximations and numerical models predict cooling ages in and around crustal plutons in steadily exhuming environmentsLarge plutons emplaced in the middle crust at 10–15‐km depth can reset low‐temperature thermochronometers in the upper crust [ABSTRACT FROM AUTHOR]

Step heating is an important tool in the derivation of thermochronologic models based on diffusive noble‐gas loss from minerals. This technique investigates noble‐gas diffusion in minerals at length scales of natural crystals. Like any scientific measurement, step heating requires realistic assessment of assumptions and uncertainties; however, uncertainties are often not presented or roughly approximated. Here we propagate errors associated with temperature, step duration, evolved gas quantity, and diffusion domain size. Other potential error sources (e.g., nonideal shapes, fractures, and zonation of aliquots) are not discussed. We provide error propagation formulas for the derivation of diffusivities and diffusion parameters for infinite plane sheet, spherical, and infinite cylinder geometry. We show that a variance in uncertainty (heteroscedasticity) in diffusivity and temperature may lead to erroneous estimates of activation energy (Ea) and frequency factor (D0) and an underestimation of their uncertainties during unweighted regression. The effect becomes significant if the variance in uncertainty exceeds a factor of two to five. The effect of the difference in D0 values is demagnified in the calculation of closure temperature (which calls on lnD0 rather than D0) and its uncertainty. To make this a practical resource, we provide spreadsheets with a step heating data set, diffusivity calculations with associated analytical error propagation formulas, and unweighted and weighted regression models to derive Ea and D0 for all three geometries. We also provide spreadsheets with Monte Carlo and numerical error propagation for plane sheet geometry. Key Points: As a practical resource we provide spreadsheets with a sample step heating data set, coded error propagation formulas, and regression modelsRegression of Arrhenius trends without error propagation may lead to erroneous estimates of diffusion parameters and their uncertainties [ABSTRACT FROM AUTHOR]

Information about the "External Influences on Ecological Theory: Report on Organized Oral Session 80" during the 100th Anniversary Meeting of the Ecological Society of America is presented. Topics discussed during the session include the Lotka and Volterra's models of predation and competition based on logistic growth equation, genetics and ecology. The session featured speakers including Aaron Ellison, Matthew Lau and Xichen Jiang.

Abstract: In the deep biosphere, microbial sulfate reduction (MSR) is exploited for energy. Here, we show that, in fractured continental crystalline bedrock in three areas in Sweden, this process produced sulfide that reacted with iron to form pyrite extremely enriched in 34S relative to 32S. As documented by secondary ion mass spectrometry (SIMS) microanalyses, the δ34Spyrite values are up to +132‰V‐CDT and with a total range of 186‰. The lightest δ34Spyrite values (−54‰) suggest very large fractionation during MSR from an initial sulfate with δ34S values (δ34Ssulfate,0) of +14 to +28‰. Fractionation of this magnitude requires a slow MSR rate, a feature we attribute to nutrient and electron donor shortage as well as initial sulfate abundance. The superheavy δ34Spyrite values were produced by Rayleigh fractionation effects in a diminishing sulfate pool. Large volumes of pyrite with superheavy values (+120 ± 15‰) within single fracture intercepts in the boreholes, associated heavy average values up to +75‰ and heavy minimum δ34Spyrite values, suggest isolation of significant amounts of isotopically light sulfide in other parts of the fracture system. Large fracture‐specific δ34Spyrite variability and overall average δ34Spyrite values (+11 to +16‰) lower than the anticipated δ34Ssulfate,0 support this hypothesis. The superheavy pyrite found locally in the borehole intercepts thus represents a late stage in a much larger fracture system undergoing Rayleigh fractionation. Microscale Rb–Sr dating and U/Th–He dating of cogenetic minerals reveal that most pyrite formed in the early Paleozoic era, but crystal overgrowths may be significantly younger. The δ13C values in cogenetic calcite suggest that the superheavy δ34Spyrite values are related to organotrophic MSR, in contrast to findings from marine sediments where superheavy pyrite has been proposed to be linked to anaerobic oxidation of methane. The findings provide new insights into MSR‐related S‐isotope systematics, particularly regarding formation of large fractions of 34S‐rich pyrite. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the cement paste compositon on the spalling of concrete in fire According to Eurocode 2, part 1‐2, explosive spalling of concrete in fire is unlikely to occur when the moisture content of the concrete is less than k % by weight. Above k % a more accurate assessment of moisture content, type of aggregate, permeability of concrete and heating rate should be considered. In a research project carried out at the VDZ, it was investigated which moisture contents and distributions are typically present in concretes of different compositions under normal environmental conditions in order to allow to assess in which cases explosive concrete spalling is unlikely according to Eurocode 2, part 1‐2. At the same time, own experimental investigations were carried out on the influence of the concrete composition and the moisture content on the occurrence of spalling when concrete is heated. For this purpose, a test set‐up (“PTM test”), described for the first time by Kalifa, was modified by applying a lateral compressive stress. In the PTM test, the change in pore pressure, temperature and mass in a concrete specimen is measured while heating the surface with electric radiant heaters. The VDZ tests showed that the compressive stresses that were applied were decisive for the occurrence of explosive spalling. Furthermore, the experimental results show that high pore pressures are not the main cause of the occurrence of spalling. [ABSTRACT FROM AUTHOR]

Summary: Objective: To assess the changes resulting from the changes from UICC/AJCC TNM version 7 to version 8 and to subsequently determine whether TNM version 8 is an improvement compared to previous iterations of the TNM system and other staging systems for differentiated thyroid cancer (DTC) with regard to prognostic power. Design: Database study of DTC patients treated in our centre between 1978 up to and including 1 July 2014. Results were compared to our previous comparison of prognostic systems using the same data set. Patients: 2257 DTC patients. Measurements: Staging in accordance with TNM 7 and TNM 8. Thyroid cancer‐specific mortality; comparison was based on p‐values of univariate Cox regression analyses as well as analysis of the proportion of variance explained (PVE). Results: There is a redistribution from stage 3 to lower stages affecting 206 (9.1%) patients. DTC‐related mortality according to Kaplan‐Meier for younger and older patients in TNM 7 had a slightly lower prognostic power than that in accordance with TNM 8 (P = 8.0 10−16 and P = 1.5 10−21, respectively). Overall staging is lower in 627/2257 (27.8%) patients. PVE (TNM 7: 0.29; TNM 8: 0.28) and the P‐value of Cox regressions (TNM 7: P = 7.1*10−52; TNM 8: P = 3.9*10−49) for TNM version 8 are marginally lower than that for TNM version 7, but still better than for any other DTC staging system. Conclusion: TNM 8 results in a marked downstaging of patients compared to TNM 7. Although some changes, like the change in age boundary, appear to be associated with an improvement in prognostic power, the overall effect of the changes does not improve the predictive power compared to TNM 7. [ABSTRACT FROM AUTHOR]

Summary: Background: The use of pulse oximetry in horses is limited due to inadequate readings with conventional transmission sensor probes. Objectives: The objectives of this study were to 1) develop an improved sensor design for horses to be used at an appropriate anatomical site, and 2) evaluate this design in an experimental study. Study design: In vivo experiment. Methods: A new sensor design for reflectance pulse oximetry at the buccal mucosa was developed. A conventional Nonin 2000SL sensor for transmission pulse oximetry was included into this design. Three different prototypes (N1, N2a, N2b) were constructed and used with the Nonin 2500A Vet pulse oximetry monitor. Thirteen anaesthetised warmblood horses were included into a desaturation protocol (100–70% SaO2). SpO2 and pulse frequency values were recorded, using SaO2 calculated from blood gas analysis and invasive pulse frequency measurements as reference methods. Bias and precision were evaluated by calculations of the root mean square deviation (Arms). The agreement of the methods was tested with Bland‐Altman analysis. Results: The quality of the pulse frequency readings determined the quality of the SpO2‐readings. Good pulse signal strength resulted in a SpO2‐accuracy comparable to that of the original sensor (Nonin 2000SL: Arms = 3%; N1: Arms = 3.60%; N2b: Arms = 3.46%). Especially at heart rates ≤30 bpm, pulse rate readings that were about twice as high as the reference value occurred. Their exclusion from the dataset resulted in a pulse rate accuracy similar to that of the original sensor. Bland‐Altman plots showed limits of agreement typical of pulse oximeters. Main limitations: The pulse frequency accuracy requires further improvement. The usability in clinical cases needs to be tested. Conclusions: The new sensor design has been shown to be suitable for buccal pulse oximetry in horses. [ABSTRACT FROM AUTHOR]

We previously reported that a low level of lysosomal photodamage potentiated the phototoxic effect of subsequent mitochondrial photodamage mediated by the benzoporphyrin derivative (BPD) in murine hepatoma 1c1c7 cells. This was attributed to release of Ca2+ from damaged lysosomes and a calpain-mediated conversion of the autophagy-related protein ATG5 to a pro-apoptotic fragment. We now report a comparison of these results with those obtained with the human non-small-cell lung cancer A549 cell line. A549 cells contained lower levels of ATG5 and were less responsive than 1c1c7 cultures to the PDT combination. A rapid appearance of caspase 3/7 activation together with formation of condensed chromatin indicated initiation of apoptosis in both cell lines, but to a lesser extent in A549 cultures. Both cell lines became highly vacuolated within 16 h of combination PDT or an equivalent phototoxic dose from BPD alone. The vacuole periphery was labeled with a fluorescent probe for the endoplasmic reticulum (ER), and vacuole formation was prevented by presence of the protein synthesis inhibitor cycloheximide. These effects are characteristics of a caspase-independent death mode termed paraptosis previously associated with ER stress. These studies suggest that paraptosis may be a more frequent outcome of PDT than has hitherto been realized. [ABSTRACT FROM AUTHOR]

Creativity describes the potential of any human being to make something new and relevant for the environment, by means of metacognitive strategies which are particularly based on breaking out of familiar structures and recombining existing knowledge. In chemistry research, creativity most notably is needed in five moments: generating research questions, planning experimental investigations, formulating hypotheses, generating theories and models and presenting research results. Jacobus Henricus van 't Hoff, who reflected on the role of imagination in science as early as the 19th century, and Stefan Hell, who even in the face of adversity overthrew a scientific postulate, that seems to be irrevocable for more than 100 years, are two examples, which are suitable to illustrate the role of creativity in chemistry. [ABSTRACT FROM AUTHOR]

Paranodal demyelination has been discussed as a potential mechanism of nerve fiber damage in diabetic neuropathy ( DNP). Studies on human tissue are limited, as nerve biopsies are invasive and only rarely performed in patients with confirmed DNP. Skin biopsy has recently been suggested as a tool to analyze paranodal and nodal changes of myelinated fibers. We analyzed the myelinated fibers of skin biopsies of 35 patients with DNP, 17 patients with diabetes mellitus ( DM) without neuropathy, and 30 normal controls. Immunofluorescence of skin sections with antibodies against Caspr, neurofascin, sodium channels, and myelin basic protein was performed to assess paranodal/nodal architecture, segmental demyelination, and myelinated nerve fibers. Staining with antibodies against protein gene product 9.5 was used to quantify unmyelinated nerve fibers. There was an increase of elongated Ranvier nodes and a dispersion of neurofascin at the distal leg in patients with DM with and without neuropathy and at the finger in patients with DNP. An increased dispersion of Caspr was only found in biopsies of the finger in patients with DNP. Skin biopsy may be an appropriate tool to analyze nodes of Ranvier in patients with DM. Structural nodal changes are detectable in DNP and even in diabetic patients without neuropathy. [ABSTRACT FROM AUTHOR]

Craton cores far from plate boundaries have traditionally been viewed as stable features that experience minimal vertical motion over 100-1000 Ma time scales. Here we show that the Fennoscandian Shield in southeastern Sweden experienced several episodes of burial and exhumation from ~1800 Ma to the present. Apatite, titanite, and zircon (U-Th)/He ages from surface samples and drill cores constrain the long-term, low-temperature history of the Laxemar region. Single grain titanite and zircon (U-Th)/He ages are negatively correlated (104-838 Ma for zircon and 160-945 Ma for titanite) with effective uranium (eU = U + 0.235 × Th), a measurement proportional to radiation damage. Apatite ages are 102-258 Ma and are positively correlated with eU. These correlations are interpreted with damage-diffusivity models, and the modeled zircon He age-eU correlations constrain multiple episodes of heating and cooling from 1800 Ma to the present, which we interpret in the context of foreland basin systems related to the Neoproterozoic Sveconorwegian and Paleozoic Caledonian orogens. Inverse time-temperature models constrain an average burial temperature of ~217°C during the Sveconorwegian, achieved between 944 Ma and 851 Ma, and ~154°C during the Caledonian, achieved between 366 Ma and 224 Ma. Subsequent cooling to near-surface temperatures in both cases could be related to long-term exhumation caused by either postorogenic collapse or mantle dynamics related to the final assembly of Rodinia and Pangaea. Our titanite He age-eU correlations cannot currently be interpreted in the same fashion; however, this study represents one of the first examples of a damage-diffusivity relationship in this system, which deserves further research attention. [ABSTRACT FROM AUTHOR]